DEPARTMENT OF THE INTERIOR 

FRANKLIN K. LANE, Secretary 

UNITED STATES GEOLOGICAL SURVEY 

GEORGE OTIS SMITH, Director 

Professional· Paper 89 

THE FAUNA OF THE CHAPMAN SANDSTONE 

OF ~IAINE 

INCLUDING DESCRIPTIONS OF SOME RELATED SPECIES 

FROM THE MOOSE RIVER SANDS'rONE 

BY 

HENRY SHALER WILLIAMS 

ASSlSTED BY 

CARPEL LEVENTHAL BREGER 

'V ASI-IINGTON 

·GOVERNMENT PRIN1'1NG OFFICE 

1916 

CONTENTS. 

Page. 

Preface................................................................................................. 5 

Chn.pn1an sandstone .............................................................. : . . . . . . . . . . . . . . . . . . . . . . 7 

Species from Moose River sandstone:.................................................... . . . . . . . . . . . . . . . . . 12 

Other fossils described in this report .................................................................... ;... 13 

Species of the Chapman fauna and a few related forms from other formations ........................... :. . . . 14 

Crolenterata ................... :. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14 

Vermes............................................................................................... 15 

l\folluscoiclea ............................................................................... :. . . . . . . . . 19 

Bryozoa. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19 

Brachiopoda .. ·_..................... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20 

Lingulidre ........................... ·. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20 

Discinidre ........................................ , ................................. : . . . . . . . . 21 

Craniidre.................................................................................... 24 

Strophomenidre...... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25 

Productidre ................................... ·............................................... 44 

Orthiclre. . . . .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ... . 57 

Rhynchonellidre .............. ·. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 63 

Terebratuliclre. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 76 

Spirifericlre ..................................................... ~............................ 76 

Athyriclre.................................... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 118 

Mollusca.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 126 

Pelecypocla ................................................... : . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 126 

Solenopsidre ................................................................... ·. . . . . . . . . . . . . . 126 

Grammysiitlre .......... ~.................................................................... 127 

Cyrtoclontidre ...................................................... ·......................... 147 

Nuculacea................................................................................... 156 

Ctenodontidre, Nuculidre, and Lecliclre ................ .' ............. ~...................... 156 

N.uculidre............................................................................... 172 

Pteriacea ........ ~.......................................................................... 177 

Pterineidre ............................ : . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 177 

Conocardiidre ......................... ·................................................... 201 

· Pteriiclre ................... .' ...... · ......... ·.............................................. 202 

l\fyaliniclre. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 212 

l\fodiolopsidre .................................... ·. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 216 

N aiadacea. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 236 

Cardiniidre. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 236 

Trigoniacea ................................................... .'. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 238 

1'rigoniidre ............ . t. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 238 

Astartacea ........................ :......................................................... 239 

Astarticlre................................................................................ 239 

Solenacea. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 249 

Solenidre .......................................................................... : . . . . 249 

Lucinacea ................................. : ................ ·.·............................... 257 

Luciniclre............................................................................... 257 

. Gastropoda...................................................................................... 259 

Capulidre .................................................................................... · 259 

Bellerophontidre ......................................................................... -.. . 263 

Pleurotomaridre........ . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 273 

Trochidre.......... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 276 

Pseudomelaniidre ................................................................. ·........... 279 

Cephalopoda. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 282 

Orthoceratidre ................ ·. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 282 

Pteropoda. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 283 

Tentaculitidre ................................................ : . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 283 

3 
4 CONTENTS. 

Species of the Chapman fauna and a few related forms from other formations-Continued. Page 

A.rthropoda.......................................................................................... 285 

Crustacea ....... ~ .. · . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 285 

Trilobita ............................. : . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 285 

Ostracoda....................................................................................... 289 

Beyrichiidre ............. :.................. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 289 

Vertebrata ..................................... : ........................... ~ .. ~..................... 293 

Plantre ...................................................................................... ·........ 293 

Appendix.... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 295 

Age and correlation of the Chapman sandstone ............................... ·........................... 295 

Fauna of the Moo5le River sandstone ...................................... · ...................... _...... 299 

Sou.rce of the species of the Chapman fauna ........................................................ ,... 299 

Index .... ·................................................................................................ 337 

ILLUSTRATIONS. 

Page. 

PLATES I-XXVII. Fauna of the Chapman sandstone ............................ ~ ................... · .... 301-S35 

FIGURE 1. Map of volcanic area in Aroostook County, Maine................................................ 8 

2. Surface ornamentation of Spirifer arenosus var. sirnplex.......................................... 87 , 
PREFACE. 

·By HENRY SHALER wILLIAMS. 

In the year 1897 I began all: investigation of the Paleozoic rocks and fossils of Maine, in the 

hope of gaining through their study a better understanding than was then to be had from 

published literature of the relation between the well-known upper Paleozoic of Europe and that 

of the interior of ·the North American continent. 

A preliminary report, based mi the evidence already possessed and the new facts obtained 

by field work in Aroostook County, was published in 1900.1 In that report I gathered lists 

of fossil faunas of Maine at that time published and discussed their bearing on the problems 

of classification and correlation of the formations concerned. I also there referred to the special 

itn):>ortance of the fossils of the Chapman sandstone as the expression of an intermediate fauna 

linking together the faunas of New York and those of the Tilestone, or terminal Silurian, of 

Great Britain. As the Tilestone marked the uppermost boundary of the Silurian for the British 

section, a full exposition of the facts for correlation of the European and American geologic 

sections was in1portant. As this boundary in Great Britain represented also the passage for a 

considerable area from the marine Silurian up into the estuarine conditions of t~e Old Red 

sandstone, it was believed that a careful study of the relations of the successive faunas and the 

changes· in sedimentation associated with the several faunules would prove of value in establishing at least one stratigraphic boundary by which the sections of the two continents might 

be precisely compared. 

The fauna of the Cl~apman sandstone was therefore selected for special study and description. Further collections were made from the typical localities in Aroostook County by Olaf 0. 

Nylander for the United States Geological Survey, and additions were also made to the 

fauna of the Moose River sandstone, a related but later fauna, by a set of fossils collected by 

I-Im·old ';V. Prince at Detroit, Somerset County, :Maine. I was enabled to examine the Gaspe 

and Arisaig faunas tlu•ough the com·tesy of the officers of the Canadian Survey. 

In order that the British related sections might be n1ore accurately defined, the committee 

·of the International Congress of Geology on stratigraphic classification was urged at the Berlin 

congress in 1.898 to designate geologists of each country to establish with greater precision the 

systen1 boundnry lines, the typical definition of which was based on the sections of their l~espective countries. Although the chairman of the committee, Dr. Renevier, reported unfavorably 

upon this proposition, the English n1ember of the committee, Prof. T. M. Hughes, of Caulbridge, established the standard upper boundary of the Silurian at Dudley, thus furnishing 

an accurate definition of the "passage beds" in which the exact section is given and the exact 

faunal contents of each zone defined. 2 

During the preparation of the present work the English col,ections most closely associated 

with the Chapman fauna were also studied, but it was discovered that hardly any of the species 

are strictly identical, although n1any affinities are close. The pelecypods particularly in the 

British collections were found to show such variation in specific characters that redefinition 

and refiguring of n1miy of the specimens would be necessary before it would be possible to 

make COJ?lparisons with precision. 

t Willimns, H. S., and Gregory, H. E., Contributions to tho geology of 'Maine: U.S. GeoL Survey Bull. 165, 1900. 

2 Ellos, G. L., and Slater, I. L., Tho highest Silurian rocks of the Ludlow district: Geol. Soc. London Quart. Jour., vol. 42, pp. 195-222, PI. 

XXII, map, 1906. . 

5 
6 FAUNA OF THE CHAPMAN SANDSTONE OF MAINE. 

In this country, while the investigations here recorded were in progress, Charles Schuchert, 

J. M. Clarke, C. E. Beecher, and others have contributed much additional information concerning the faunas of the Helderberg and Oriskany, so that greater precision of correlation with 

the sections in New York and the interior is now possible than when this work was begun. 

After the descriptions of n1ost of the species had been written out and the figures prepared, 

some readjustment of nomenclature was necessitated by the publication by the State geologist 

of New York of descriptions of species of the same faunas of Maine from ·specimens furnished 

to him by Mr. Nylander. . 

As the work proceeded it became important to have lists of all the closely related species 

mentioned in American and European formations. In the preparation of these lists and the 

associated bibliography I had the valuable assistance of Mr. Carpel Leventhal Breger, who 

has also done an imn1ense amount of enthusiastic work in recording-the minute· details 9f structure of the species under investigation. 

In the preparation of the present paper !t was originally intended to confine the study to 

an elaboration of the Chapman sandstone faunas alone, but comparison of species has led to 

the introduction of several species from closely related faunas, particularly those of the Moose 

River sandstone, of somewhat later age, exposed in Somerset County in central and northern 

Maine. Descriptions of a few of these species not previously named and described are included, 

but no attempt has been made to give an exhaustive account of the Moose River fauna. 

Several other Paleozoic faunas of Maine await elaboration and will furnish material for 

interesting monographs. 

Although it has been possible as a result of this work to throw some light upon the problen1 

of correlation of formations on the two sides of the Atlantio, I fully appreciate that only a small 

beginning has been made. The present paper will, however, I think, serve to stimulate future 

paleontologists to continue this work and attain the rich results which this line of investigation 

promises to yield. 

NoTE.-The omission of reference to much interesting literature bearing upon the correlation of the Chapman 

fauna now (1915) in the hands of geologists may be explained by the following statements: The manuscript of tills professional paper was mainly complete in the year 1906. Delay in publication led to the elimination of several chapters in 

1910, when it was entirely revised and prepared for publication. It has been in the custody of the Geological Survey 

· since 1910, and it would require so much additional matter to properly discuss the questions which have arisen since 

the text was written that it has seemed best to print the paleontologic matter as it is and reserve for future discussion 

the correlation problems, which are still unsettled and upon which the fossils will throw new light. 

HENRY S. WILLIAMS. 

WASHINGTON, March 5, 1915. 
THE FAUNA OF THE CHAPMAN SANDSTONE OF MAINE, INCLUDING 

DESCRIPTIONS OF SOME RELATED SPECIES FROM THE MOOSE 

RIVER SANDSTONE. 

By I-IENRY SHALER WILLIAMS, assisted by CARPEL LEVENTHAL BREGER. 

CHAPMAN SANDSTONE. 

The Chapman sandstone is exposed over a small area in Chapman Town.ship 1 (T. 11, R. 3), 

Aroostook County, :Maine, a few miles west of Presque Isle ap.d south of Aroostook River. This 

exposure is shmvn on the ncc01npanying geologic map (fig. 1) by the southern half of the sandstone area west of Presque Isle, in the township marked "11-3." The north.ern part of the 

sandstone outcrop in -:Mapleton Township (T. 12, R. 3), marked "12-3," is the Mapleton sandstone. The two sandstone n1asses are separated by large knobs of andesite, marked "3, 3, 3" 

on the 1nap, two of which are kno·wn locally as Edmunds Hill and IIobart Hill. 

No contact of either of these sandstone masses with underlying sedimentary rocks has 

been seen, but structurally they appear to have been deposited unconformably upon the Silurian 

liJnestone or shale beds of the region. The general dip of both sandstones. is northwesterly, and, 

as I stated in a preYious reportzThe Mapleton sandstones are believed to be of more recent age than the Chapman rocks but were probably continuous with them, and the two may represent the base and succeeding strata of the Gaspe sandstone of Gaspe Peninsula. 

The Chapn1an sandstone includes at least 500 feet of medium fine grained brown to gray 

sandstone, in no place conglomeratic, much of it thick bedded, with some fine-grained shaly 

layers separating the beds. In these shaly sandstones occur most of the fossils, which are 

1narine. I-Iere and there fragments of plants (Psilophyton, etc.) appear in the sandstone. In 

the supposedly overlying ~1apleton sandstone only plant fossils haYe been discoYerecl. 

The typical exposure of the Chapn1an sandstone is along the east (right) bank of the south 

branch of Presque· Isle Stream, about a n1ile from the south line of Chapman Township and 

about a :mile west of Tweedys, on the road running southwestward from Presque Isle. The 

specimens fr01n this locality are labeled 1099 A .. The specimens labeled 1099 L came from a 

single sandy stratun1 150 feet fron1 the top of the exposure at which collection 1099 A was 

obtained. Collection.1099 J came fron1 an outcrop about 2 miles west of the locality of collection 1099 A, and collection 1099 K from a point 2:} 1niles west of the south branch of Presque 

Isle Strean1. 

The fossils labeled 1099 Care from the Chapman sandstone at the foot of Edmunds Hill, 

underlying the andesite which forms the n1ass of that knob. 'Specimens from the talus heap on 

the west side of Edmunds flill are labeled 1099 M. 

The following list shows the species and varieties belonging to the Chapman fauna, the 

localities fron1 which they came being indicated in the columns on the right by letters which 

correspond to the letters distinguishing the collections mentioned above: 

1 Chapman 'l'ownship was called Chapman Plantation on tho map of Walling & Chaco, published in 1862, which accounts for tho uso of tho 

term Ch!~pman Ph1ntation in some of tho literature of later date. 'l'he areas appear to bo the same. -

~Contributions to tho geology of Maine: U. S. Geol. Survey Bull. 165, p. 88, 1900. 

7 
8 FA UN A OF THE CHAPMAN SANDSTONE OF MAINE. 

~Aroostook limestone· 

~Arenaceous limestone 

~Fossiliferous limestone 

(.:-::::.:;·::::1 SandstOne 

-~Slates and schists 

~Granite ~ 

~~~~:.n~&m Rhyolite 

-~ ~Ad nes1 "te 

~Tr ~ ach yte 

· ~~~t:S;~·~ 

~ 

Quartz trachyte (bostonite, rhyolite) 

.. ~Teschemte 

.~D1aase ~-b • 

fa'ijt§,z:~~ Volcanic tuff 

. -~Manganiferous iron ore 

(g~i;-~ :Mars Hi!! c~nglomerate 

0 5 10 20Miles ~~~~~~~3CE~c=========~• 

FIGURE 1.-Map of Aroostook County volcanic area, Maine. Reprinted from U. S. Geol. Survey Bull. 165, Pl. IV. 
CHAPMAN SANDSTONE. 9 

Fauna of the Chapman sandstone. 

Localities. 

l. Pleurodictyum cf. P. problematicum Goldfuss.................. . . . . . . . . . . . . A ....................... . 2. Favosites sp. indet. _... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . M · ............................. . 3. Comulites serpularius Schlotheim ......................... :. . . . C ................................... . 4. 'l'rachyderma (?Gyrichnites) speciosa sp. nov. . . . . . . . . . . . . . . . . . C ................................... . 5. Polypora cf. P. lilrea Hall.................................... . . . . . . . . . . . . . . . . . . . . . . . . J ........... . 6. Polypora cf. P. psyche Billings............................... C ................................... . 7. Lingula minuscula sp. nov..................................... . . . . . . . . . . . . . . . . . . . . . . . . J ........... . 8. 01·bi~u~oid~a(H.oemerella) discus Hall ...................... ;.. C . . . . . . . . . . . . L J ........... . 9. Cranta sp. 1ndet............................... . . . . . . . . . . . . . . . . . . . . . . l\f ............................. . 10. Leptostrophia perplana (Conrad)............................... . . . . . . M ............................. . p .. Le~trena rhomboidali~ Wilckens... . . . . . . . . . . . . . . . . . . . . . . . . . . . . C M: ......••...................... 12. Sc lUChcrtella defornus Hall.................................. C M: ............................•. 13. Hipparionyx unguiformis Conrad ....... :....................... C M ............................. . 14. Chonetes striatissimus sp. nov.................................. C . . . . . . . . . . . . . . . . . . J K 

15. Chonetes novascoticus Hall.................................... . . . . . . M: ............................. . Hi. Dalmanella planoconvexaHall .................. ·.............. . . . . . . M: ............................•. 17. Dalmanella cf. D. circularis Sower by.......................... . . . . . . M ............................. . 18. Dalmanella (Mystrophora) elevata sp. nov...................... C ................................... . 19. StenoscismaformosaHall ............................................ l\£ ................•............• 20. Stenoscisma formosa, Hall (young)............................. C ................................... . 2l. Rhynchonella cf. mainensis Billings. . . . . . . . . . . . . . . . . . . . . . . . . . C ................................... . 22. Eatonia s.ingular.is Vanuxem.................................. M: .............................• 23. Beachia chapmani sp. nov . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . C ................................... . 24. Megahnteris sp.? .......... , ............................ ~ . . . . C . . ...................... . 25. Rensselaeria mainensis Williams. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . C · · M ·· · · ~~ · · L K B' 

26. Eunellaellsi(Clarke) ............ · ............................... · .... M: ................•....•......•• 27. Cyrtina heteroclita a var. nov ........... , ..... ·-.......... . . . . . . . . . . . M ............................. . 28. Cyrtina rostrata Hall ................ · ........ :................ ?C M ............................. . 29. SpiriferconcinnusHall ....................... : ................................. L ............ B•-a 

30. Spirifer cyclopterus Hall. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . C M: . . . . . • • . . . . • . . . . . . . B 2 

31. Sf.irifer slxtrsus Cl~·ke......................................... C ...... ~ ~ ~ ~ ~. L J ........... . 32. Nucleosl)tra ventncosa Hall.................................... C . . . . . . . . . . . . . . . . . . . . . . . . K 

33. Meristelad.M.bellaHall ........................................... M .............................. . 

~~: ~~t1~~a~~!~~a~£;~~{~p-. -~~~, ~ ~::::::::::::::::::::::::::::::: .. ~ __ :::::: : ::::: :::::: -· ·j ·- :::: :·: :::::: 

36. Grammysia acaclica Billings, var ........................... ·_.. C ................................... . 37. Grammysia elymelloicles sp. nov ......................................... : A ........................ . 38. Grammysia modiomorphre (Clarke)................ . . . . . . . . . . . . C ................................... . 39. Physetomya sp._ inclet........................................ . . . . . . M: .............................• 4.0. Elymella harns1 sp. nov. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . C · ................................... . 41. Glossites amnigenoicles sp. nov .................... ,............. C ......................... l ......... . 

42. Gloss.ites barranclii sp. nov..................................... . . . . . . M ............................. . 43. Gloss.itescf. G. clepressusReed (not.Hall) ... , ......................... M ............................. . 4<J. Cle~dophorus curt us sp. nov •............. ; .................... - C ................................... . 45. Cle1clophorus perovahs sp. nov........ . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . :M ............................. . 46. Myoplusia chapmani sp. nov.................................. . . . . . . . . . . . . A ....................... . 47. Telliniteschapmani sp. nov.......................................................... J ........... . 48. Tellinites curta sp. nov. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . M ............................. . 49. Tellinites (Koenenia) gibbosa Goldfuss var. kayseri Beushausen. . . . . . . . . . . . . A J ........... . 50. Tellinites.gibbosa var. crassa Beushausen...................... . . . . . . . . . . . . . . . . . . . . . . . . J ........... . 51. Paleoneilo (Ditichia) mainensis Clarke .............. ·........... C ................................... . 52. Paleoneilo (Ditichia) mainensis umbonata var. nov.............. . . . . . . ?M: A . . . . . . J ........... . 53. Leda harrisi sp. nov........................................... . . . . . . . . . . . . . . . . . . . . . . . . J ........... . 54. Lecla min uta sp. nov.......................................... . . . . . . . . . . . . 1\. ....................... . 

55. Nuculoiclea cf. N. aquisgranensis.Beushausen.................. . . . . . . l\f ............................. . 56. Nuculoiclea bellatula sp. nov................................... . . . . . . M ............................. . 57. Nuculoidea cordata sp. nov................................... C. . .................................. . 58. Nuculoiclea trigonale sp. nov................................... . . . . . . M ............................. . 59. Actinopterella aroostooki (Clarke)........ . . . . . . . . . . . . . . . . . . . . . . . . . . . . M: ....... _ ..................... . 60. Actinopterella aroostooki erecta var. nov........................ . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . B 4 

61. Actinopterella aroostoold planicosta var. nov.. . . . . . . . . . . . . . . . . C ................................... . 62. Actinopterella concentl'ica sp. nov. . . . . . . . . . . . . . . . . . . . . . . . . . . . C M ............................. . 63. Actinopterella radialis (Clarke) ................ ·................. . . . . . . . . . . . .. . . . . . . L ................. . 

!i: 1~~~gi~;~\\HH: ::::::::::::::::::::::::::::::::::::::::: :::::: :::::: .. ~ :::::: :::::: ::i~:::::::: 67. Pteromtella quadrata sp. nov .................................. ; . . . . . . . . . . . . . . . . L ................. . 68. I..imoptera pauciracliata chapmani vru·. nov. . . . . . . . . . . . . . . . . . . . C ..................... : . ............ . 69. Preavicula breva sp. nov. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . J ........... . 19. Pr~avict~Ia·<;>bl_onga (Hall) gen. nov............................. C . . . . . . . . . . . . . . . . . . J K 

71. JJ~10}?ter1a r1es1a_na sp. nov......... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . I-' ................. . 72. Myu ma maurenana sp. nov. . . . • . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A L ................. . 73. ~yalina maureriana lata vru·. nov........ . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . L ............ I ..... ~ 
10 FAUNA OF THE CHAPMAN SANDSTONE OF MAINE. 

Fauna of the Chapman sandstone-Continued. 

Localities. 

74. Myalina m·aureriana pterinreoides (Clarke)...................... . . . . . . . . . . . . . . . . . . L ................. . 75. Conocardium? dubia sp. nov ................ ; . . . . . . . . . . . . . . . . . . . . . . . . . . . . A ....................... . 76. Modiomorpha aroostook sp. nov •.............. · ........................... _ . . . . . . L ................. . 77. Modiomorpha cf. M. protea Clarke.............................. C ................................... . 78. Modiomorpha sp. indet ................ , .......................................................... B z 

79. Modiomorpha (cf. Endodesma) chapmani sp. nov................ C M ............................. . 

~~: &~:~~k~~: ~a:;~~o~r ~~: ·_ ._._._ .. ·:::::::::::::::::::::: : : : : : : : : : : : : :: .. ~ .. : : : : : : : : : : : : · · i · · : : : : : : : : : : : : 

82. Sphenotomorpha rigidula gen. et sp. nov......................... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . K 

83. C1mitaria chapmani sp. nov •............................ _ . . . . . . . . . . . . .. . . . . . A ....................... . 84. Anodontopsis maccoymna sp. nov.............................. . . . . . . . . . . . . . . . . . . L J ........... . 

~~: ~~~~~~~:~ r;~r:~t~~~ -~~~::: ~ -.-.-.-_·:::: : : : : : : : : : : : : : : : : : : : : : : : g : : : : : : ::: : : : : : : : : : : : : : : : : : : : : : : : : : : : 

87. Cypricardella bellatula sp. nov •.......... _ .... _ . . . . . . . . . . . . . . . . . . . . . . . . . . . . A ................... _ ... . 88. Cypricardella cf. C. bicostula Krantz........................... . . . . . . M. . ............................ . 89. Cypricardella rotundata sp. nov................................ . . . . . . M ............................. . 90. Cypricardella transversa sp. nov •.. :........................... C ................................... . 91. Paracyclas bulloides sp. nov........ . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . J ........... . 92. Palreosolen chapmani sp. nov................................. . . . . . . . . . . . . A ....................... . 93. ·Platyceras (Orthonychia) aroostooki sp. nov..................... C ................................... . 94. Platyceras (Orthonychia) compressa sp. nov ... :................ . . . . . . M ............................. . 95. Platyceras chapmani sp. nov................................... C M ............................. . 96. Platyceras edmundi sp. nov. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . C ................................... . 97. Platyceras (Orthonychia) hebes Clarke........................ . . . . . . M .............................. . 98. Platyceras (Orthonychia) hebes var. a ................. ............ ·... M ............................. . 99. Platyceras (Orthonychia) hebes var . .B-........................ . . . . . . M ............................. . 100. Strophostylus sp. cf. S. globosus Hall.......................... C ................................... . 101. Bellerophon (Plectonotus) trilobatus Sower by.......... . . . . . . . . . C . . . . . . . . . . . . . . . . . . J K 

102. Tropidodiscus obex Clarke.................................... C M . . . . . . . . . . . . . . . . . . K B 

103. Tropidodiscus minimus americanus var. nov................... . . . . . . . . . . . . . . . . . . . . . . . . J ........... . 104. Mesoccelia tenuella sp. nov ........... .' ........... : ............. ·.·... . . . . . . . . . . . . L ................. . 105. Mesoccelia? sp. (near M. compacta Hall) ........................... _-.. . . . . . . A ....................... . 106. Ccel~dium cf. C. planogyratum HalL.... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . L ................. . 107. Gomostropha chapmam sp. nov........ . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . J ........... . 108. Pseudotectus hitchcocki Clarke.................................... . . . . . . . . . . . . A ....................... . 109. Pseudotectus? decidu us sp. nov ............................................... ~.. . . . . . . J ........... . 110. Pseudotectus(?) sp. indet .............................. _....... C ................................... . 111. Holopea (Aunptygma) heushauseni Clarke..................... ?C ?M , A L J ?K ..... . 112. Tentaculites schlotheimi Koken............. . . . . . . . . . . . . . . . . . . . C M . . . . . . . . . . . . . . . . . . K 

113. Orthoceras sp. (? 0. norumbegre Clarke)....................... C ¥ ............................. . 114. Homalonotus laticaudatus sp. nov............................ C M . . . . . . . . . . . . . . . . . . K 

115. Homalonotus vai:mxemi HalL ............................ _.... . . . . . . . . . . . . . . . . . . . . . . . . J ........... . 116. Phacopidella chapmani sp. nov............................... . . . . . . M ............................. . 117. Dalmanite~ (? Synphoria) asp. nov........................... C .................................... . 118. Dalmanites (? Synphoria) .B sp. nov ....... ~................... . . . . . . M ............................. . 119. Zygobeyrichia extrema Ulrich................................ C A J ........... . 120. Zygobeyrichia apicalis Ulrich....... . . . . . . . . . . . . . . . . . . . . . . . . . . C A J ........... . 121. Zygobeyrichia devonica Jones and Woodward .. -:............... C A J ........... . 122. Ctneobolbina (?) corn uta Ulrich............................... C A J ........... . 123. Asterolepis clarkei Eastman ....................... ,........... . . . . . . . . . . . . . . . . . . . . . . . . J ........... . . 124. Psilophyton princeps? Dawson (not with marine fossils)......... . . . . . . . . . . . . A ....................... ·. 125. Indetermined wood stems (not with marine fossils)............. . . . . . . . . . . . . A ....................... . 

During the preparation of this report the State geologist of New York, J. M. Clarke, 

described a number of the species belonging to the Chapman fauna,t giving them specificnames. Some of these species are identical with those for which my descriptions had already 

b.een written; for them Clarke's names have been substituted. Others imperfectly diagnosed 

by Clarke have been described in the present text. In the following list all these species are 

cited with references to the pages in Clarke's report where they are discussed. The names 

indented in the list are those assigned by Clarke to species herein described under different. 

names, which are also given. This list and the one preceding comprise all the species known 

to belong to the Chap;man fauna at the date of- completion of this report. 

· 1 Clarke, J. M., Some new Devonic fossils: New York State Mus. Bull. 107, pp. 153-291, May, 1907. 
CHAPMAN SANDSTONE. 11 

Spe~sjrom-Chapman Township described by J. M. Clarke, 1907. 

EdmundsHW. 

Page in 

Clarke's 

report. 

1. Phacops (Phacopidella) nylanderi Clarke ...................................... _ . _ ..... . 166 

2. Tentaculites scaln.ris Schlotheim (see T. schlotheimi Koken of present report, p. 283). 174 

3. Orthoceras norumbegre Clarke ............... -......................................... . 177 

4. Platyceras hebes Clarke (seeP. (Orthonychia) hebes of present report, p. 260) ........ · 185 

5. Platyceras kahlebergensis (Beushausen) (see P. chapmani sp. nov. of present report, 

p. 259)-------- ... - -.. - - --- ... - - - -...... - . - --- .. - - - -.... - -.. -.. - . - - --- - . - . - --- -- 185 

6. Loxonema cf. funatum (A. Roemer) (possibly L. jerseyense Weller) .................... . 186 

7. Holopea beushauseni Clarke (see H. (Auriptygma) beushauseni of presei1t report, 

p. 281).--------------.-- ... -.. -.... -- ............ ---------.---.-------.- .. -- .. . 188 

8. Tropidocliscus obex Clarke (see present report, p. 270) .............................. . 193 

9. Pterinopecten aroostooki Clarke (see Actinopterella aroostooki of presentreport, p. 187). 199 

10. Pterinea chapmani Clarke (apparently a species of Actinopterella) ..................... . 203 

11. Pterinea edmuncli Clarke (see Actinopterella aroostooki of present report, p. 189) .... . 203 

· 12. Pterinea edmundi var. subrecta Clarke (see Actinopterella aroostooki var. erecta of 

present repor"t, p. 189) .......................................... _ .............. . 204 

13. Pterinea brisa Clarke (apparently a species of Limoptera). ~: ...... ~ .................... . 208 

14. Modiomorpha vulcanalis Clarke (apparently a member of the CYl-todonta group, also in 

part the Mocliomorpha aroostooki of present report) ............................. . 219 

15. Modiomorpha protea Clarke (see present report, p. 219) ............................. . 220 

16. Grammysia mocliomorphre Clarke (see present report, p. 138) ........................ . 221 

17. Spirifer aroostookensis Clarke ......................................................... . 258 

18. Spirifer macropleuroides Clarke ...................................................... . 259 

19. Chonetes aroostookensis Clarke (see C. novascoticus Hall of present report, p. 45) .... . 264 

20. Chonetes paucistria Clarke ............................................................ . 266 

21. Leptostrophia magnifica Hall, protype parva Clarke (see L. perplana (Conrad) of 

present report, p. 27) .......................................................... . 274 

22. Hipparionyx minor Clarke (see H. unguiformis (Conrad) of present report, p. 41) ... . 278 

23. .Dalmanella drevermanni Clarke (see D. planoconvexa Hall of present report, p. 57) .. . 286 

Presque Isle Stream. 

Holopea beushauseni Clarke (see No. 7 above)...... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 188 

24. Cooliclium tenue Clarke (see Mesocoolia tenuella of present report, p. 273) ......... _·_.. 190 

25. Eotomaria hitchcocki Clarke (see Pseudotectus hitchcocki of present report, p. 278).. 190 

26. Pterinea cf. fasciculata Goldfuss (see Ac~nopterella concentrica sp. nov. of present 

report, p. 190).. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 204 

27. Pterinea. radialis Clarke (see Actinopterella radialis (Clarke) of present re.port, p. 184). 207 

28. Pteronitella peninsulre Clarke (see Actinopterella radialis (Clarke) of present report, 

p. 184).------------.---.------.-- .... ---- .. -----.------------- ... -- ...... -.... - 212 

29. Myalina pterinreoides Clarke (see M. maureriana sp. nov. var. pterin::eoicles of present 

report, p. 215). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 213 

Modiomorpha protea Clarke (see No. 15 above)...................................... 220 

30. Leptodomus communis Clarke. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 224 

31. Leptodomus corrugatus Clarke......................................................... 224 

32. Paleonello malnensis Clarke (see P. (Ditichia) mainensis of present report, p. 168).... 230 

33. Palreoneilo circulus Clarke (see Tellinites gibbosa var. kayseri BeushauAen of present . 

report, p. 165).................................. ... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 231 

34. Nucula cf. N. krachtre A. Roenier (possibly Myoplusia chapmani sp. nov. of present 

report, p. 162) .......... _...................................................... 232 

35. Paleosolen simplex Maurer (Chapman specimens are the young of P. chapman.i, p. 251). 235 

36. Rensselaeria atlantica Clarke (seeR. mainensis of present report, p. 72).............. 243 

37. Spirifer subcuspidatus var. late.incisus Scupin (seeS. concinnus Hall of present report, 

p. 80):-.---.-----.-------- .... --- ... ----- ... --- .... ----.--- ............... --.--- 254 

38. Spirifer cyminclis Clarke (see S. cyclopterus Hall of present report, p. 88)............ 255 

39. Spirifer cymindis var. sparsa Clarke (see S. sparsus of present report, p. 105).......... 257 

Examination of the lists of species shows that two somewhat distinct faunules are· recognizable in the general Chapman sandstone· collections. One of these faunules comprises the 

faunal aggregates from Edmunds I-Iill (localities 1099 C and 1099 M) and the other the collections from Presque Isle Stream and the region to the west (localities 1099 A, 1099 ~' 1099 J, 
12 FAUNA OF THE CHAPMAN SANDSTONE OF MAINE. 

and 1099 K). As the general inclination of the beds over Chapma:t:t Township is northerly, it 

is probable that the Edmunds Hill faunule is from a zone stratigraphically higher than the beds . 

on Presque Isle Strean1, although it is, possible that faulting may disturb the succession. Of the 

127 species and varieties described in the present report 66 are peculiar to the Edmunds Hill 

faunule, 48 are peculiar to the beds along Presque Isle Stream, and 13 are species common to 

both. Thirty-five Chapn1an species have been recognized elsewhere. 

S.PECIES FROM :M;OOSE RIVER SANDSTONE. 

In preparing descriptions of the Chapman sandstone fauna, specimens of allied faunas 

were brought in for comparison. Some of these it was found desirable to describe and illustrate in order to make clear the relation of the normal species of the Chapman fauna to the 

allied species of the same genetic series .. Some. of these extraneous fossils are well-known 

landmarks in the stratigraphic column and serve to indicate the relation of the fauna in which 

they occur to. that of the Chapn1an sandstone. Most of these closely allied forms con1e from the 

formation known as the Moose River sandstone, which outcrops west ·of the_ region of the Chapman sandstone in Somerset County. · 

Study of this Moose River fauna leads to the opinion that it is of later a.ge than the Chapman sandstone fauna. The Moose River sandstone contains several species common to the fauna 

of the Oriskany sandstone of New York State and the Appalachian region. It also contains 

Spirijer gaspensis Billings and some lamellibranchs which suggest that it has affinity with 

the fauna of the "Unter-Coblenzian" of the Rhenish Lower Devonian. 

The principal fossil localities of the Moose River sandstone are given in the following ~ist. 

Most of these collections were made by Gilbert Van Ingen in 1889 for the United States Geological Survey and were roughly identified in preliminary lists made by me and published in 

1909.1 

1059 C. Parlin Pond. A section beginning on Parlin Stream at the middle dam, where the stream runs more than 

· a mile over the sandstones and shales of the Moose River formation. 

1059 D. Jackman farm. A section on Canada Road, in the town of Jackman, 10 miles south of Moose River settlement and 5 miles north of Parlin Pond. 

1059 D 1. A section on the east side of Canada road, at Bean Brook, 3 miles north of Parlin Pond Hotel. 

1060 A. Ledges at the northwest end of Long Pond, forming islands in the lake. 

1060 B 4. A ledge on the south shore of Long Pond, 5~ miles west of the outlet. 

1061 A. A section on the south shore of Little Brassua Lake, along the Canadian Pacific Railway, beginning at 

milepost 237 and extending southward. 1 

1061 B 1. A hard, tough sandstone, with shaly partings, on Stony Brook. 

1062. Exposures on shores and islands of Big Brassua Lake. 

1062 B. Brassua Stream, extending upstream from a point 2 miles above the lake. 

· 1062 A 1, B 2, B 6, B 7, C 3. Outcrops along Brassua 'Stream. 

1100 A. Detroit. 

All the foregoing fossil localities of the Moose River sandstone are in Somerset County, 

Maine. The collectio~1s fron1 Detroit, Maine, were furnished to the Geological Survey by Mr. 

Harold Prince, a resident of that village. According to Mr. Prince, "some were found in the 

ledge on Parlin Stream, I! or 2 miles below Parlin Pond, Somerset County, l\1aine; the others 

were found in drift rock at various points 1n an almost direct line fron1 Parlin Pond to Detroit, 

in the southeast corner of the county. The larger brachiopods (Chonetes and Leptostrophia) 

were found in drift at the Forks Plantation." 

In the present paper reference is made to the following species from the Moose River 

sandstone of Somerset County: 

Locality 1062. Brassua Stream: 

Schuchertella woolworthana (Hall); p. 34, Pl. III, fig. 10. 

Spirifer duodenarius Hall; p. 104, Pl. IV, figs. 3, 4. 

Locality 1061. Little Brassua Lake: 

Spiriier gaspensis Billings; p. 107, Pl. IV, fig. 7. 

1 Williams, H. S., and Gregory, H. E., Contributions to the geology of Maine: U.S. Geol. Survey Bull. 165, pp. 88 et seq., 1900. 
SPECIES FROM MOOSE RIVER SANDSTONE. 

Locality 1100 A. Parlin Pond, or in drift between pond and Detroit: 

Leptostrophia perplan~ (Conrad); p. 27, Pl. VIII, figs, 1, 2, 4, 5, 16; Pl. XI, fig. 17. 

Chbuetes novascoticus var. canadensis Billings; p. 45, Pl. XI, fig. 16; Pl. X, figs. 30, 31; Pl. IX, figs. 20, 21. 

Chonostrophia complanata (Hall); p. 55, Pl. X, fig.·4. 

Spiri.fer arenosus Conrad; p. 84, Pl. II, figs. 15, 16, 19, 21; Pl. V, fig. 18. 

Spirifer murchisoni Castelnau; p. 95, Pl. I, figs. 3, 10, 23, 25, 26; Pl. II, fig. 9. 

Antispirifer hanolcli gen. et sp. nov..; p. 116, Pl. V, figs. 1-13. 

Leptocrelia flabellites (Conraq); p. 120, Pl. V, figs. 19-30. 

Grammysia. (Grammysioidea) princiana sp. nov.; p. 136, Pl. XX, fig. 8. 

Cypricardites detroitense sp. nov.; p. 155, Pl. XXIII, figs. 14, 15. 

Follma.unella ma.inensis (Clarke); p. 179, Pl. XVI, figs. 1-6; Pl. XVII, figs. 1-11. 

Actinopterella tenuiradiata sp. nov.; p. 191, Pl. XVII, fig. 18. 

Megambonin. cardiiformis Ha.ll; p. 199, Pl. XXIV, fig. 4. 

Megambonia cardiiformis var. parviusctlla var. nov.; p. 201, Pi. XIX, fig. 23. 

Platyostoma ventricosmn; p. 262, Pl. XIII, figs. 15, 18. 

Pa.tellostium revolvens sp. nov.; p. 265, Pl. XIV, figs. 14, ~5, 20, 27. 

Plectonotus trilobatus (Sowerby); p. 266, Pl. XIV, fig. 19. 

Tropiclocliscus somerseti sp. nov.; p. 271, Pl. XIV, fig. 22. 

Loxonema \'velleriana sp. nov.; p. 279, Pl. XIII, figs. 2, 3, 5. 

Loxonema jerseyense Weller; p. 280, Pl. XIII, figs. 1, 4. 

'l'entaculites schlotheimi Koken; p. 283, Pl. XIV, figs. 23, 24; Pl. V, fig. 30. 

'l'enta.culites cf. elongatus Hall; p. 284, Pl. XIV, fig. 26. 

OTHER FOSSILS DESCRIBED IN THIS REPORT. 

13 

In addition to the material from l\1oose River sandstone referred to above, specin1ens 

fr01n other localities and forn1ations are figured and discussed in the text, as follows: 

Dennys River, Eastport quadrangle, Washington County, Maine, from the Pembroke formation: " 

Chonetes hastini Willia.ms, p. 48; Pl. VIII, fig. 25. 

St. Helens Isla.ncl, near Montreal, Canada, from a limestone breccia, some of the limestone fragments of which contain 

Helderberg, others Oriska.ny, and still others later fossils: 

Spirifer concinnus Hall; p. 80, Pl. II, fig. 4. 

Spirifer montrealensis sp. nov.; p. 113, Pl. I, fig. 2; Pl. II, figs. 2, 18. 

Kayser, Mineral County, W. Va. (Oriskany): 

Spirifer arenosus Conrad; p. 84, Pl. III, fig. l. 

Spirifer arenosus var. simplex var. nov.; p. 86, Pl. III, figs. 2-4, 7, 12. 

Covington, W. Va. (Oriskany): 

Sp:irifer concinnus Hall; p. 80, Pl. III, fig. 5. 
SPECIES OF THE CHAPMAN FAUNA AND A FEW RELATED FORMS · 

FROM OTHER FORMATIONS. 

C<ELENTERATA. 

The Chapman fauna is evidently of marine habitat, but it is remarkably lacking in definite 

traces of Crelenterata. The only forms that can be referred to that subkingdom are a few traces 

of the peculiar fossils which have for a long time been widely known under the name Pleurodictyum problematicum Goldfuss and a sandstone mold which is referred with doubt to Favosites; 

they are described beyond. Both of these genera are consistent with the other genera of the 

fauna in locating it stratigraphically in early Devonian time. The Pleurodictyum is significant of 

Lower Devonian (Gedennian, Taunusian, and Coblentzian) affinities in Europe, though its range. 

in North America has been supposed t9 be scarcely lower than the Onondaga ("Corniferous") 

limestone. The small size of the Chapman for1:p. may signify either new and unfavorable, 

environment or simply an early stage of evolution of the type. Whichever interpretation is 

given, the evidence points toward affinities with the Eo-Devonian faunas of Europe rather than 

with the Meso-Devonian faunas of the interior of North America or with the Silurian. · 

Subbranch CNIDARIA. 

Class ANTHOZOA. 

· Subclass HEXACORALLA Haeckel. 

Family FAVOSITID.tE Milne-Edwards and Haime. 

Genus PLEURODICTYUM Goldfuss 1820. 

PLEURODICTYmi cf.. P. PROBLEMATICmi Goldfuss. 

Plate XXIV, :figure 2. 

A single small specimen, internal mold (magnified 2 diameters in fig. 2 of Pl. XXIV),. 

shows the typical characters of Pleurodictyum. It has a small corallum; greatest diameter 

14 n1illimeters. Corallites numerous (more than 70 can be counted on the specimen) and 

irregularly prismatic in forn1, with tubular pores connecting the neighboring corallites. The 

small-sized corallum and larger number of corallites distinguish it from the ordinary forms, as 

described, of P. problematicu.m, owing to the imperfect knowledge of Goldfuss's types and the, 

loose usage of the specific name. We propose for our material the name Pleurodictyun1 cf. 

P. problematicum Goldfuss. · · 

Locality: Chf!.pman sandstone, Presque Isle Stream, Chapman Township, Aroostook 

County, Maine. 

U. S. National Museun1, catalogue No. 5~681. 

Genus FA VOSITE S Lamarck. 

FA VOSITES ( ~) sp. indet. 

Plate XXII, :figure 16. 

The ~pecimen figured appears to be a sandstone mold of the exterior surface of a hemispherical coral, the only structure evident being the subconical rounded fillings of what are. 

14 
VERMES. 15 

interpreted to have been the open ends of the cells of some such coral as Favosites helderbergire 

}!all. In the original the axis of the cells opened obliquely to the surface. As well as· can be 

estimated from the molds the cells were not more than 2 millimeters in diameter, but the coralla 

evidently attained a large size. 

Locality: Chapman sandstone, west side of Edmunds Hill, Chapman Township, Aroostook County, Maine. 

U. S. National l\1useum, catalogue No. 59682. 

VERMES. 

Suborder TUBICOLA (SEDENTARIA). 

Genus CORNULITE S Schlotheim. 

CoRNULITES SERPULARrus Schlothei1n cf. var. MAJOR Barrande. 

Plate XIV, figure 25,-

cf. 1867 .. Cornulites major. Barrande, Systeme silurien du centre de la Boheme, vol. 3, p. 174, pl. 16, fig. 13. 

Calcairo moyen, etage F: Konieprus and Mnienian, Bohemia. 

Baudo inferior £1 : Lochkov, Bohemia. 

Bande superieure e 2 : Lodenitz and Listice, Bohemia. 

cf. 1888. Cornulites major. Hall, Paleontology of New York, vol. 5, pt. 2, supplement, pl. 116 (A), fig. 14. 

A con1plete synonymy of the various fossils called Oornulites serpulanus by authors has 

not been attempted, but the following list includes most of the n1ore important references: 

1820. Cormdites serpularius. Schlotheim, Petrefaktenkunde, p. 378, pl. 29, fig. 7. 

''Transition limestone'': Gotland, Baltic Sweden. 

]834. Cornulites serpularitts. Kloeden, Versteinerungen d. Mark. Brandenburg, p. 227, pl. 3; fig. 13. 

·Glacial-drift bowlders: Mark. Brandenburg, Germany. 

1839. Cornul,ites serpulari'us. Sowerby, in Murchison, 'l'he Silurian system, p. 627, pl. 26, fig. 5. 

Wenlock shale: Western slopes of the Mal vern· Hills, Dudley, England. 

1845. Cornutites serpttlaritts. Murchison, De Verneuil, and Keyserling, Russia and the Urals, vol. 2, p. 27, pl. 27, fig.10. 

1851. Cornulites serpularitts. McCoy, in Sedgwick and McCoy, British Paleozoic rocks and fossils, p. 63. 

Upper Ludlow quartzite: Benson Knot and Brigsteer, Kendal, 'Vestmoreland, England. 

Wenlock limestone: Dudley, England. 

1854. Cornul'ites serpularius. Keyserling, Soc. geol. France Bull., 2d ser., vol. 11, p. 152. 

Neo-Silurian: Esthonia, Baltic Russia. 

1859. Cornulites serpularius. Salter, in Murchison, Siluria, 2d eel., p. 221. 

1865. Cornulites serpularius. Kjerulf, Veiviser ved geologiske Excursioner i Christiania, pp. 17, 23, 27. 

Malmo limestone etage 8(3 [Aymestry]: Malmo, Norway. 

Lower l\blmo group etages 6 ~ncl 7 [Eo-Silurian]: Christiania region, Norway. 

Oscarshalllimy sandstone etage 5a [basal Silurian or Neo-Ordovician]: Husberg~en, Norway. 

1872. Cormdites serpularius. Nicholson, Am. Jour. Sci., 3d ser., vol. 3, p. 202, figs. la, lb. 

Wenlock limestone: Dudley, England. 

1876. Cormtl-ites proprius. Hall, New York State Mus. Nat. Hist. Twenty-eighth Ann. Rept., adV?nce eel., pl. 31, 

fjgs. 1-13; public ed., 1879, p. 182, pl. 31, figs. 1-13. 

Waldron beds: Waldron, Incl. 

1881. Cornulites proprius. Hall, Indiana State Geologist Eleventh Ann. }\ept., p. 327, pl. 32, figs. 1-13. 

Waldron beds: Waldron, Ind. 

1888. Cornulites proprius and serpularius. Hall, Paleontology of New York, vol. 5, pt. 2, supplement, pp. 8, 21; pls. 

11.5, 116, 116 (A). 

Wenlock limestone. See Sowerby's localities, 1839. 

Waldron beds: Waldron, Ind. 

1905. Cornulitos cf. serJJUlaritts . . Williams, U.S. Geol. Survey Prof. Paper 35, p. 22. 

Upper Silurian: \Vhitings Bay, Maine. 

Some. poorly preserved fragments which are apparently too large and somewhat too 

irregular in growth to belong to Tentaculites are referred to Schlotheim's species. 

Tube a very gently tapering one, very nearly or quite straight; an.nulated;· free (except 

perhaps in infancy); cross section elliptical. The sides of the cone converge very slightly; 

in a length of 6 millimeters the larger diameter has been observed to expand from 3.85 to 4.65 
16 FAUNA OF THE. CHAPMAN SANDSTONE OF MAINE. 

millimeters. In this length ten annulations occur. In a second specimen from the same layer 

of rock the larger diameter of the elliptical cone expands 3.9 to 4.8 millimeters in a distance 

of 5.8 millimeters; six annulations were counted. In the latter specimen, the internal mold 

figured, the annulatimis when examined closely are seen to bear a resemblance to the truncated broad ends of overlapping cones which have the apices directed toward. the distal or 

broader end of the shell. The annulations are slanting or twisting, less frequently transverse; 

they are subequidistant. Finer surfac«;l markings not preserved. 

The Chapman Cornulites differ from the . ordinary Helderberg and Oriskany Cornulites 

in their larger size and in being free. The Cornulites hitherto known in North America from 

these formations cm:;nprise the following: 

1860. Cornulites flexuosus var. gracilis. Hall and Dawson, Canadian Naturalist, vol. 5, no. 2, pp. 140, 155. 

Oriskany iron-ore beds: Nictau, Nova Scotia. 

Arisaig and Stonehouse [Upper Ludlow] formations: Arisaig, Nova Scotia. 

1888. ·Cornulites chrysalis. Hall, Paleontology of New York, vol. 5, pt. 2, supplement, p. 20, pl. 116, figs. 26-28. 

Helderberg [New Scotland] shaly Umestone: Near Chtrkesville, Albany County, N. Y~ 

1888. Cornulites cingulatus. Hall, idem, p." 20, pl. 116. 

Helderberg: New York State ("locality doubtful"). 

Oriskany, Becraft Mountain, Columbia County, N. Y. 

The Chapman specimens resemble very closely Barrande's Oornulites major, which differs 

from the normal Oornulites serpularius chiefly in its size, straighter form, and more regular 

and closely set annulations. In the Pembroke fauna of the Eastport quadrangle, ~1aine, the 

genus Cornulites attains a profuse and varied development, representing several large species, 

one of which resembles the Chapman sandstone form. 

There is also a similarity between the Chapman Cornulites and certain free forms classed 

as Tentaculites, particularly the Oriskanian Tentaculites elongatus flail. This Tentaculites is 

very commonly somewhat flexuous/ especially in the juvenile portion and in many specimens 

the annulations are not strictly transverse. 

Locality: Chapman sandstone, Edmunds Hill (locality 1099 C), Chapman Township, Aroostook County, Maine. · 

U. S. National Museum, catalogue No. 59683. 

Genus ORTONIA Nicholson. 

The genus Ortonia was founded in 1872 by Nicholson 2 to include fLxed, adheren~, conical 

calcareous tubes which are attache,d along the whole of one side to some foreign body, typically 

a brachiopod or mollusk. The tubes are generally loosely gregarious, several occurring together 

on a foreign surface, but they are not in· contact with one another except by accident. Hall 

in 1888 3 showed that this is one of the growth· stages assumed by Cornulites. To represent 

this mode of growth in Cornulites the term Ortonia may be retained, but it is not strictly 

of generic value. 

CoRNULITES (0RTONIA) MAINENsrs s'p. nov. 

Plate XIV, figure 29. 

Tubes conical, slightly flexuous, annulated exteriorly, interior smooth or with only obscure, 

transverse, distant strire, elevated on the ,internal mold. Annulatio~s on the exterior somewhat oblique.· Surface covered with very fine longitudinal lines. The specimen shows eight 

tubes radiating from an approximately con1mon center. All are attached throughout their 

length to a large Leptostrophia. The tubes are about 7.5 n1illimeters long; the· width at the 

aperture is 2 n1illimeters. The surface annulations are fine, even, and closely set; they are 

distinct and· even in: the earlier portion of the tubes, but near the aperture become more uneven, 

more distant, and unequally so and somewhat more oblique. The annulations are in the form 

1 Consult ·weller, Stuart, Paleontology of New Jersey, vol. 3, Paleozoic faunas, pl. 50, figs. 4, 5, 1903. See also Clarke, J. M., New York State 

Mus. Mem., vol. 3, No. 3, pl. 3, figs. 8, 9, 1900. 

2 Gecl. Mag., vol. 9, 1872; vol. 10, 1873. 

a Hall, James, Paleontology of New York, vol5, pt. 2, supplement, p. 20, 1888. 
VERMES .. 17 

of the exposed ends of overlapping cones, but these cones are directed with their apices toward 

the apex of the tube, the reverse of their direction in Oornulites serpularius. The radiate or 

longitudinal strire are rather obscure but are evidently present. 

Locality: l\1oose River sandstone, Detroit, Somerset County, :Maine. 

U. S. National Museun1, catalogue No. 59684. 

Oomparisons.__:_A solitary Oornulites cingulatus found incrusting an Orthothetes in the 

Oriskany of Becraft Mountnin, N. Y.,t bears close rese1nblance to this species. Oornulites 

cingulatus I-Iall, in its stnall size, incrusting habit, and constant irregularity in the distal annulations, strongly resembles Ortonia mainensis, hut Hall's species is a solitary form and typically 

incrusts a bryozoan, whereas the Maine specimens are loosely gregarious upon brachiopod 

shells. A still more in1portnnt distinction is that the Ortonia described above is nearly sn1ooth 

on the interior, whereas Oornulites cingulatus is annulated on the interior. 

'fhere is a close resemblance between our speci1nen and the Ortonia described and figured as 

Oornulites jlexuosus Hall. 2 This form, which occurs in the Ordovician, has the conic annulations 

on the exterior surface reversed in direction as in the Maine Ortonia. Both incrust strophoInenoid brachiopods, and .apparently the only observable distinctions between these two species, 

so greatly removed stratigraphically ar·e of minor importance. The Maine species has the distal 

annulations 1nore distant when compnred with the youthful stage· of the shell, indicating irregularity of growth at maturity or senility. This character is seemingly not so well developed in 

the Trenton Oornulites (Ortonia) fiexuosa, which is also not quite so smooth on the interior as 

Ortonia mainensis. 

The only Devonian Ortonia hitherto known, 0. intermedia Nicholson,S is more regularly 

annulate and has a thicker shell. 

Genus TRACHYDERMA Phillips. 

Genus GYRICHNITES Whiteaves. 

The genus Trachydenna was founded by Phillips 4 in 1848 to include annelidan remains 

differing from the common Serpulidre ·in having a large, long, flexible, free tube or epidermis 

which is corinceous, not calcareous. The tubes, which occur parallel to the bedding, are in 

described forn1s of Trachydeflna from 5 to 25 millin1eters thick, cylindrical through by far the 

greater part of their length, bluntly tapering at the extrmnities, and covered with raised 

transverse 1narkings. 

In the type species, Trachyderma coriacea Phillips, these transverse annulations are 

sharply devated nnd bifurcate, with branches which reunite along certain longitudinal bands; 

but such highly developed bands are absent in mnny of the other species referred by authors 

to Trachydern1a. In the latter, also, the transverse markings are less regular ::lfUd n1uch less 

highly developed. In Trachyderma coriacea, furthermore, the:J;"e is 'Yhat appears to be a small 

but sharply differentiated head. The presence of this head and the peculiar characters of the 

raised annulations, which resmnble the vascular system of the lower worms, show that the 

type species, Trachyderma coriacea, not only in size but in preserved characters differs widely 

from T. squamosa. The second species described, T'/'achyderma squamosa, represents a much 

1nore common form, which wits first figured and described by Sowerby. It is conceivable that 

the typical Trachyderma of Phillips is a young c01nplete form, of which the species T. squamosa is an adult skin lacking head and tail; but as fossils these two species are quite distinct, 

and the Chapman forn1s belong to the squamosa group, as represented by the following species: 

'1839. Serpulites longissirn~ts. Sowerby, in Murchison, The Silurian system, pt. 2, p. 608, pl. 5, fig .. 1. "Locality, 

Ludlow, very abundant, Kingston, Herefordshire, and very generally throughout the upper Ludlow Rock of 

Salop, Hereford, Radnor," etc. 

1 Clarko, J. ~r., Now York Stato Mus. ~fom., vol. 3, No.3, pl. 2, fig. 35, 1900. 

1 Hall, Jarnos, Paloontology of New York, vol. 5, pt. ·2, supplement, pl. P5, figs. 41-42, 1888,= Tentaculites(?) jlexuosa Hall, idem, vol. 1, p. 92, 

pl. 29, fig. 6; p. 284, pl. iS, fig. 2. 

s Nicholson, H. A., Puloontology of Ontario, 1874, p. 122. The species is from Arkona, Canada West, in beds containing a Hamilton fauna. 

4 Phillips, John, Tho Malvern Hills compared with the Paleozoic districts of Abberley, etc., with paleontological appendbc: Mem. Geol. Survey 

Groat Britain and Mus. Praet. Geology in London, vol. 2, pt. 1, pp. 230, 331, pl. 4, 1848. 

50245°-NO. 89-16--2 
18· FAUNA OF THE CHAPMAN SANDSTONE OF MAINE. 

1848. 'Trachyderma squamosa. Phillips, op. cit., p. 332, pl. 4, figs. 3, 4. 

1858. Trachyderma (?) depressa. Giebel, Silur. Fauna d. Unter-llarz, p. 15, pl. 6, fig. 10; as Serpulites depressus. See 

also Kayser, Emanuel, Die Fauna der altesten Devon-Ablagerungen de~ Harzes, p. 48, pl. 34, fig. 13, 1878. 

· 1864. Trachyderma serrata. Salter, Geol. Soc. Londo-n Quart. Jour., vol. 20, p. 290, pl. 15, fig. 9. 

1900. Trachyderma (?) clarkii. Prosser, New York State Geologist Seventeenth Ann. Rept.., pp. 149-150, pl. 6; as 

Planolites clarkii. 

This group, in which the species from Maine is included, is characterized by the absence ( n 

of a distinctly demarcated head, no traces of whose possible presence h~ve yet been observed. 

Longitudinal bands are also absent. The tube was coriaceous, large, long, free, flexuous, 

cylindrical; apparently not penetrating or crossing the bedding planes; more or less distinctly 

marked on the surface by transverse raised wrinkles or annulations .. 

That this group represents some annelidan tube and is not a "trail" is shown by the 

completely cylindrical outline; and that it is not a burrow is proved by its nearly constant 

occurrence parallel to the bedding planes of the rock. All the described species of Trachyderma fron1 the Silurian and Devonian are recorded as being parallel 'to the bedding planes; 

but Salter 1 mentions a chitinous tube which he saw in Ordovician rocks erect and perpendicular to the bedding planes. 

Some large trails, suppos.edly annelidan, from the lower part of the Gaspe sandstone, 

Gaspe, Quebec, were described by W. E. Logan in 1863. At a height of 1;100 feet above 

the Gaspe limestone several successive surfaces in. slabs of sandstone "are marked by serpentine impressions, about an inch wide, deeply grooved into the stone, marked by small parallel 

transverse furrows which are about a quarter of an inch apart. These' are perhaps worm 

track~, and are associated with a few bivalve shells of the genus Rensselaeria, probably R. 

ovoides." 2 These supposed tracks were subsequently figured and described as Gyrichnites 

gaspensis gen. et sp. nov.3 According to Whiteaves's photographs of slabs of these remains 

the trails are only 12 to 15 millimeters in diameter, rather than an inch, as estimated by 

Logan. The annulations are strongly elevated, rounded, transverse, or more often somewhat 

oblique, about a third as wide as the interspaces, and from 10 to 14 have been counted in a 

length of 60 millimeters. · 

Whether Gyrichnites gaspensis represents "trails" or actual cylindrical tubes of Annelida 

could be definitely ascertained by examining. both sides of split slabs bearing these fossils and 

noting whether the cross section is circular and closed or sen1icircular or crescentic and open 

above. Thrs has apparently not yet been done. If it could be thus definitely shown that these 

fossils are really annelidan tubes (which appears very probable, judging from the depth of the 

impressions) and not trails, the. group of species described above as Trachyderma of authors 

would find a place 1nore easily under Gyrichnites. 

The finding of this form, whether it be regarded as specifically or only generically related 

to the species described by Sowerby and Phillips, is interesting as showing affinity between 

the faunas of Arisaig, the Upper Ludlow of England, and the Chapman of Maine. 

In the upper beds of the series along the north shore of Nova Scotia at Arisaig I have seen 

several specimens closely allied to Serpulites longissimus Sowerby. Fragments of them were 

obtained, but the better specin1ens could not be removed with the tools at harid. The black, 

shining appearance of the specimens indicated original leathery or chitinous skin, which ·was 

buried and cruahed in the process. 

In the Jermyn Street Museum, London, are several specimens, no two exactly alike. The 

larger forms are from one-third to one-half inch wide, with wrinkles crossing the center as if 

they had shrunk in drying and a stiffening of the edges indicating a sheath of smne thickness. 

All these· characters indicate close affinity, and the specimen from the Chapman sandstone 

closely resembles them. In the Jermyn S~reet Museun1 the specimen marked If 18 is labeled 

Serpulites longissimus~· other specimens, marked I~ 21 and I~ 22, both fron1 the Lower Ludlow, 

J Geol. Soc. London Quart. Jour., vol. 20, p. 290, 1864. 

2 Geology of Canada, 1863, p. 399. 

a Whiteaves, J. F., Roy. Soc. Canada Trans., 1882, p. 109, pls. 11, 12. 
' MOLLUSCOIDEA. 19 

arc labeled SerJJUlites longissim'l.ls~· and specinlcn I: 24 is called Tr·achyderma squamosa, but all 

f l al.l T: 7 l d b . l f IX ·our are muc 1 1 <c. rac,~yc erma conacea 1s represente y specm1ens 48 anc 49 o 5 . 

As defined by Phillips it shows appearance of a head part, differing in this respect and in size 

fi'Oin the larger fonn Trachyderma squamosa, specimens of which are n1arked 52, 53, and 54. 

In the latter set the cross wrinkles vary .greatly in width, showing probably that the width 

and frequency of t~1e wrinldes, though in a general wny signifying the state of flexibility of the 

skin, were variable. 

In the South I{ensington Museun1 are severn1 specimens of Trachydermct squamosa from 

tho Wenlock and Aymestry and of T. coriacea from the Upper Ludlow. 

Both of these species are in collections of the Upper Ludlow in the Sedgwick Museun1 of 

Cambridge, where the larger specin1ens are labeled Serpulites longissimus and the snutller form 

Trachydermct coriacea. In the Can1bridge Museum, also, is a slttb with 01·thoceras tenuicinctum 

frmn the Upper Ludlow, Woolhope, on which is a fragment 1nuch like Trachyderma squnmosa. 

The Chapn1an specin1en crm be distinguished from any of the individual specin1ens from 

the Ludlow beds of Great Britain, but the discovery of the species in A1nerica only in the .far 

eastern outcrops of Arisaig and Maine points to common origin for the North American and 

Europm"Ln forms of this peculiar fossil. 

TRACHYDERMA ( ~ GYRICHNITES) SPECIOSA. sp. nov. 

Plate XXII, figure 20. 

Annelidan tube large, cyHndrical, not calcareous, free, prostrate, not penetrating across 

the bedding planes, so far as is apparent. Tube curved, 9t to 9I 1nillimeters wide, marked on 

the surface by transverse, parallel, low, rounded, raised annulations from two-fifths to threefifths as wide tl.S the intervening grooves; nine such grooves have been counted in ~length of 

45 n1illin1eters. The single specimen, for1ning a central fragment in external1nolds, is 85 millinleters long. The specimen resembles a deeply grooved trail, but one end was originally 

cylindrical, so that it could not possibly have been a surface trail. The 1nold is parallel 

to the horizontal bedding planes in the beautifully laminated sandstone iii which the specimen 

occurs. The transverse itnnulntions on the surface, though rather low, are much more 

distinct on the specimen than on the photographed illustration. The tube is filled with sand 

n.t one point. 

Locnlity: Chapman sandstone, Edn1unds Hill, Chapn1an Township, Aroostook County, 

:M1tino: 

U. S. N 11.tional Museum, catalogue No. 59685. 

Oompa,risons.-The nearest analogous fonn is Gyrichnites gasperisis Whiteaves, from which 

the present specimen differs chiefly in its snutller width and its somewhat less pronounced 

a.nnulations. · 

No r01nains of the chitinous or coriaceous test have been observed. Incidentally it may 

be stated that indications of the test are also lacking in specin1ens of T.? clctrkii Prosser and 

Gy·richnites gasJJensis Whiteaves, both of which are preserved in arenaceous beds. · The test 

in T. deJJressa Giebel, which is preserved in calcareous rock, is stated by Kayser to be calcareous, 

not chitinous. 'rhe chitinous test positively exists in T. squamosa Phillips and similar species 

from Arisaig, Nova Scotia, and fron1 the Eastport quadrangle, Maine. 

MOLLUSCOIDEA. 

Class BRYOZOA Ehrenberg. 

A few fragments in an i1nperfect state of preservation represent the Bryozoa. Although 

none of them furnish very satisfactory evidence of their specific characters, a few of the better 

specimens have been selected for illustration. They represent the fenestelloid form, distinguished from Fenestella under the nan1e Polypora McCoy, by having J?-O median ridge on the 
20 FAUNA OF THE CHAPMAN SANDSTONE OF MAINE. 

celliferous side of the rays. As our specimens are· only fragmentary molds of the fronds, 

instead of giving them distinct .names I refer them provisionally to their nearest described 

analogues P. lilcea Hall and P. psyche Billings. Future search of the rocks may reveal better 

preserved specimens, from which closer identification may be possible. 

PoLYPORA cf. P. LILlEA Hall. 

Plate XXII, figures 2, 4, 7, 9. 

1874. Polypora lilia. Hall, New York State Mus. Nat. Hist. Twenty-s.ixth Ann. Rept., p. 96. 

1879. Fenestella (Polypora) lilrea. Hall, idem, Th.irty-second Ann. Rept., p. 165. · 

1880. Fenestella (Polypora) lilrea. Hall, .idem, Thirty-second Ann. Rept., 2d ed., p. 27. 

1883. Fenestella (Polypora) lilrea. Hall, New York State Geologist Ann. Rept. for 1882, pl. 18, figs. 19, 20. 

1883. Retepora sp. nov. Hall, idem, figs. 21-22. 

1887. Fenestella (Polypora) lilma. Hall and Simpson, Paleontology of New York, vol. 6, p. 62, pl. 18, figs. 19-22. 

1900. Polypora lilrea. Nickles and Bassler, U. S. Geol. Survey Bull. 173, p. 365. 

All the above are recorded as from the "Lower Helderberg limestone" [Helderberg group], at Schoharie and 

near Clarksville, N .. Y. 

The specimens are flat, undulating, perforated fronds. The fenestrules are oblong in shape, 

eight to ten being present in each half centimeter of length, and are arranged in-closely crowded 

divm:ging rows, which increase by implantation. In genera~ size and proportions they very 

closely resen1hle Hall's species Polypora lilcea, to which they are referred. 

Locality: Chapman sandstone, 2! miles west of Presque Isle Strean1 and Edmunds Hill, 

Chapn1an Township, Aroostook County, Ma~ne. 

U. S. National Museum, catalogue No. 59686. 

PoLYPORA cf. P. PSYCHE Billings. 

Plate XXII, figure 6. 

1874. Polypora psyche. Billings, Canada Geol. Survey, Paleozoic fossils, vol. 2, p. 11, figs. 1, 2. 

Gaspe limestone No.8 [Grand Greve]: Indian Cove, Gaspe Bay, Quebec. 

1900. Polypora (?)psyche. Nickles and Bassler, U.S. Geol. Survey Bull. 173, p. 367 . 

. Oriskany [Gaspe limestone]. 

The fronds of this species have larger fenestrules than those of Polypora cf. P. lilcea, 

but in other respects resemble that species. In the specimens studied there are five or six 

fenestrules in the length of half a centimeter; in the corresponding length in Billings's figures 

there are four to five but not quite six fenestrules. Although the specific characters preserved 

are incomplete, they give some degree of definition to the specimens, which exhibit little else 

for determination. Specimens with large fenestrules referred to this species are less common 

than the finer forms, which have been provisionally identified with P. lilcea. 

Locality: Chapman sandstone, Edmunds Hill, Chapman Township, Aroostook County, 

Maine. 

U.S. National Museum, catalogue No. 59687. 

Class BRACHIOPODA Cuvier. 

Order ATREMATA Beecher. 

Superfamily LINGULACEA Waagen. 

Family LINGULID.£ Gray. 

Genus LINGULA Bruguiere, -1789. 

LINGULA MINUSCULA sp. nov. 

Pia te VI, figure 27. 

Shell small; height 6.2 millimeters, maximum width 3.2 millimeters, two-fifths the length 

of the shell from t~e beak; sides nearly parallel.; very gently rounded anterior and posterior 

r 
MOLL USCOIDEA. 21 

extrmnities n.rcuate, subequal, the anterior very slightly narrower; cardinal angle about 90°, 

possibly n1ore. Greatest convexity 1.3 millimeters just posterior to the middle. A rather 

flat, narrow ridge occurs here and extends as fnr as the point of maximum width of the shell. 

Posteriorly, this flattened ridge slopes down m1el narrows t.o the beak; anteriorly, it gradually 

1nerges into the convexity of the shell, which is a little n1ore depressed toward the front than 

nearer the beak On this ridge, the strire 1 of growth are horizontal or even occasionally slightly 

insinuated. On the internal1nold there are obscure indications of two subparallel, very faint 

lines 1 extending from the beak forward. 

The surface ornamentation consists of fine, l.mequal, elevated, imbricose concentric strire 

of growth. Under the lens s01ne extremely fine radial or fibrous markings are observed, but 

these are probnbly nssociated with the fabrication of the shell and are not really "surface 

niarkings." 

Locality: Chapman sn.ndstone, a single specimen, 2 miles west of Presque Isle Stream, 

Chapman 'fownship, Aroostook County, :Maine. 

U. S. National :Museum, catalogue No. 59688. 

Oompwrisons.-Con1parison of fossil Lingulidre, except in extraordinary forms, is of little 

value in determining specific and stratigraphic relations. :Many points of distinction in Lingula 

fossils can hardly be expressed intelligibly in words or even shown in figures, so that si1nilar 

forn1s, which have been described under separate names but are nearly or quite identicnJ, so 

fn.r as their published figures and descriptions would indicate, 1nay range from the Cambrian 

to the Recent. The Lingula here described can be compared with small Lingula ligea Hall, 

f1·on1 the Upper Devonian of New York, and with Lingula longissima Pander,Z from. the Upper 

Ordovician, and no doubt a consCientious search ~ould show. that the species is very similar 

in visible chttracters to some Can1brian form or perhaps to some Cretaceous or Tertiary species. 

An1ong Silurian and Lower Devonian species this Lingula may be very closely compared 

with narrow fonns of the Downtonian-Passage beds, f.;ingula cornea, 3 L. minimn,.t and the 

llcrcyninn Ling'llla ilsce Roen1er. 5 Fro1n all these it differs in being slightly narrower anteriorly 

and in having tho greatest width posterior to the middle; the beaks are much more obtuae than 

in Lingula, minima/ the shell is smaller than L. ilsce and not near~y so broad as typical L. cornea 

Sowerby, though it strongly resembles the narrower forn1S referred to this species by Davidson. 

Lingula artemis Billings, 6 fron1 the G~:tspe li1nestone No. 5, is also very similar but has the ratio 

of length to width 3: 2, whereas in the present form this ratio is about 2:1. 

Order NEOTREMATA Beecher. 

Superfamily DISCINACEA Waagen. 

Family DISCINIDJE. 

Genus ORBICULOIDEA D'Orbigny, 1849. 

Subgenus R<EMERELLA Hall and Clarke, 1892. 

0RBICU:LOIDEA (RCEMERELLA) DISCUS (Hall). 

Plate VI, figures 28-33. 

1859. Discina discus. Hall, Paleontology of New York, vol. 3, p. 159, pl. 9, :figs. 13-15. 

Lower Helderberg shaly [New Scotland] limestone: Becraft Mountain, near Hudson, N.Y. 

187G. Discina discus. 'Barrett, Lyceum Nat. Hist. New York Annals, vol. 11, p. 296. 

Trilobite beds [uppermost Helderberg]: Bennett's quarry, Port Jervis, N.Y. 

L877. Discina discus. Barrett, Am. Jour. Sci., 3d ser., vol. 13, p. 387. 

Trilobite beds (uppe1·most Helderberg]: Bennett's quarry, Port Jervis, N.Y. 

\ 

1 'I' he terms "lines" and •' strire" are here used in the technical sense according to which strire are impressed and lines elevated. 

2 Davidson, Thomas, British fossil Brachiopoda, vol. 3 (Silurian), p. 51, pl. 3, figs. 28, 29, 1886. 

s Idem, pl. 2, fig. 34. 

• Idem, pl. 3, figs. 36, 37. 

~ Kayser, Emanuel, Die Fauna der ii.ltesten Devon-Ablagerungen des Harzes, pl. 30, figs. 22, 23, 1878 .. 

o Prueozoic fossils [of Canada], .vol. 2, pt. 1, p. 14, fig. 4, 1874. 
22 FAUNA OF THE CHAPMAN SANDSTONE OF MAINE. 

?1892. Schizocrania (?) discus. Hall and Clarke, Paleontology of New York, vol. 8, pt. 1, p. 132. 

Lower Helderberg group: New York. 

1892. Orbiculoidea discus. Hall and Clarke, idem, pl. 4E, fig. 13. 

Lower Helde1·berg group: Near Clarksville, Albany County, N. Y. 1 

1897. Orbiculoidea discus. Schuchert, U. S. Geol. Survey Bull. 87, p. 278. 

Lower Helderberg: Near Hudson and in Albany County, N.Y. 

1899. Orbiculoidea discus (?). Prosser, New York State Geologist Seventeenth Ann. Rept. (for 1897), p. 351. 

New Scotland shaly limestone: Oniskethau Creek, Albany County, N.Y. 

1901. Orbiculoidea discus. Schuchert, Geol. Soc. America Bull., vol. 11, p. 282. 

New Scotland and Becraft limestones: New York. 

1903. Orbiculoidea cf. 0. discus. Hartnagel, New York State Mus. Bull. 69, p. 1164. 

New Scotland gray limestone: Hill east of Manlius Village, Onondaga County, N. Y. 

1905. Orbiculoidea disctts (?). Shimer, New York State Mus. Bull. 80, pp. 223-265. 

Doubtfully identified from the lower and upper New Scotland, Trilobite Mountain, N. Y. 

The description of the Maine material of this species. is as follows: Shell large, free, circular, 

or nearly circular, with the length a trifle greater than the width. The upper (brachial) valve 

is larger than the lower (p'edicle) valv~; beak situated at distance of one-third to two-fifths the 

width of the she:p. from the margin, rarely central. Apex bluntly rounded, directed posteriorly. 

Posterior slope in profile straight or slightly sigmoid, anterior slope gently convex. Height of 

the valve between one-fourth and one-third the width. The lower (pedicle) valve, when 

uncrushed, has a depressed mammillate, subcentral beak. Posterior slope convex or sigmoidal; 

anterior slope or profile concave. The pedicle opening is elliptical to pear-shaped, continued 

posteriorly in a slit which nearly reaches the margin. Height of the· valve between one-si,xth 

and one-seventh the length. Shell substance chitinous, laminate; outer thin layer nacreous, 

with pearly luster preserved in one of the specimens. 

Surface ornamentation, strongly elevated, concentric imbricose strim, with intermediate 

finer concentric strim in the well-preserved parts. Radial markings vary from sharp strim 

visible to the naked eye to very fine, indistinct strim. These radial strim are feebly if at all 

preserved where the concentric lamellm occur, but on partly exfoliated shells are evident and 

seemingly quite regular. 

The specimens may be described as follows: 

1. Plate VI, figure 32, from Presque Isle Stream. A large circular brachial valve in external · 

mold; length 28 millimeters, width 28 millimeters, height 8 n1illin1eters. Apex rounded, about 

12 millimeters from the posterior margin; posterior profile concave. Concentric lamellose 

markings strongly developed, the raised. edges equal to one-half or one-third the width of the 

intervening spaces; on t~e ·apical portion these concentric !fiarkings are close together and 

regular. Radial markings faint or absent. 

2. Plate VI, figure 33, also from Presque Isle Stream. Another brachial valve in external 

mold; length 28.5 millimeters, width 27.3 millimeters, height 8.5 millimeters. Apex rounded, 

· distant 10 millimeters from the posterior margin. Concentric markings close-set and regular 

in apical portion; more uneven and unequal in marginal areas. Radial strire obscure but 

present. A piece of the pearly outer layer of the shell is preserved. 

3. Plate VI, figure 31, also from Presque Isle Stream. A somewhat crushed pedicle valve, 

in part (anteriorly) in external mold and in part (posteriorly) in external cast. Length 30 

millimeters, width 28 millimeters, depth 4 millimeters; widest in front. Anterior portion of 

valve deeply concave; includes the maximum depth. The depth is as great as or greater than 

in typical Rmmerella grandis (V anuxem), specimens of which from the Hamilton of Cazenovia, 

N.Y., are at hand for comparison. Under the pedicle posterior passage, just· back of the pedicle 

opening, the shell is convex; in the present large specimen it becomes again concave near the 

posterior margin. Distal end of pedicle opening 17 millimeters from the posterior margin. 

Fine, regular, close-set, radial striations are preserved on parts of exterior which show lan1ellose 

markings. 

1 Also identified by Dr. C. E. Smith in an unpublished section of the New Scotland, Countryman Hill, Helderberg Mountains, Albany 

County, N.Y. 

I 
MOLLUSCOIDEA. 23 

4. Plate VI, figure 29, a brachial valve from Presque Isle Stream, incomplete, but originally 

about 26 Inilli1ueters long, 24! millimeters wide, 7! millimeters high; apex 10 millimeters from 

1nargin; shows concave posterior profile. Shell exfoliated, exposing uneven, fine, concentric 

lines of growth; very f-ine, unequal, radial striations are also well developed. 

The four specimens described above could be regarded as typical Rremerellas, the shells 

being like Orbiculoidea but large and with deeply concave pedicle valves. This pedicle valve 

1nust have fitted up into the dmuelike cavity of the brachial valve, and every part of the large 

pedicle valve was included within this cavity-that is, the valve as a whole was distinctly 

concave. This concavity of the pedicle valve is the distinguishing feature of the genus 

Rre:merella :Hall and Clark. 

5. Plate VI, figure 30, a large, exfoliated specimen from Edmunds Hill which must have 

been about 28 n1illiJneters long, 25 n1illimeters wide, and apparently 4 millimeters high; possibly 

a pedicle valve; but if considered very broken, it n1ight equally well be interpreted as the 

higher or brachial valve. Fine prominent radial strire are preserved with concentric uneven 

lines of growth on the exfoliated parts. This shell shows pearly luster on one of the lamellre. 

The surface 111arkings are almost exactly the same as on No. 4, from locality 1099 J, and both 

specin1ens represent the san1e species. 

6. Plate VI, figure 28, a sn1all but important specimen from Edmunds llill, is an exfoliated 

convex or flat pedicle valve, representing by its convexity the normal Orbiculoidea type. 

Length of specin1en 16.5 n1illi1neters, width 13 millin1eters, height 2. 75 millimeters; like No. 3, 

this specin1en is widest in front. The valve as a whole is tather convex, thus differing fron1 the 

Rren1erella type and agreeing with Orbiculoidea. The anterior slope or profile is concave, as 

in both Rren1erella and most species of Orbiculoidea. This anterior concavity is produced by 

the upturning of the anterior margin; near the apical part the shell is convex throughout the 

circumference" and the convexity is retained posteriorly. The profile is the san1e as that 

figured for 0. discus by Hall/ except that in the present specimen the apex is central. The 

pedicle passage is fairly large; the distal end is in the middle of the shell, and posteriorly the 

passage is prolonged as a narrow groove or slit which nearly if not quite reaches the margin. 

'"rho radial n1arkings are fine linear wrinkles; in the exfoliated shell concentric strire are feebly 

developed. This specimen has the same outline as No. 3, with the same anterior concavity in 

the pedicle valve, and is almost exactly the counterpart of the younger portion of that specimen. 

Locality: Chapman sandstone, Presque Isle Stream (common); 2 miles west of Presque 

Isle Stream (rare); Edmunds Hill (occasional). All in Aroostook County, Maine. 

U. S. National :Museum, catalogue Nos. 59689, 59690, 59691. . 

Relcttion of Rmmerella to Orbiculoidea.-The facts already stated indicate that the young 

or 1niddle-aged specin1ens present a strong Orbiculoidea aspect, with the pedicle valve convex 

or depressed-convex with reference to the brachial valve; at middle age the convexity of the 

pedicle valve begins to reverse, as is common in mature forms of n1ost Orbiculoideas; and at 

1naturity or senility the pedicle valve is strongly concave, fitting up into the domelike cavity 

of the brachial valve as in the genus Rremerella. That Rremerella is ordinarily not n1erely 

a n1ature stage of Orbiculoidea is proved by the fact that the great n1ajority of Orbiculoideas 

at maturity have the pedicle valve convex as a whole, and that when most depressed the valve 

is only flat, not deeply concave and fitting into the brachial valve cavity. Furthermore, in the 

typical Rren1erella (R. grandi~) the pedicle valve assumes its concave aspect early in the developnlent of the individual and is the nonnal character at maturity, when the pedicle valve beco1nes 

concave as a whole. This would suggest that Rremerella is a valid genus derived from Orbiculoidea by acceleration of the stage of recurvature in the pedicle valve. This accelerating 

recurvature may be traced frmn the present species, in which the pedicle valve retains its 

convex, Orbiculoidea character al1uost to n1aturity, through the :Middle Devonian Rmmerella 

grandis (Vanuxem), in which the orbiculoidean convexity is apparent only in very young stages 

of growth and is the.n not well developed, and finally to the Upper Devonian Rmmerella 

1 Paleontology of New York, vol. 3, 1859, pl. 9, fig. 16a. 
24 FA UN A OF THJ!l CHAPMAN SANDSTONE OF MAINE. 

alleghania (Hall) 1 and an undescribed middle N eo-Devonian species from the vicinity of Van 

Etten, N. Y., in which the convexity of the pedicle valve, in the embryonic form, is barely 

discE<rnible. It is quite possible that the concavity of the pedicle valve characteristic of the 

genus Rremerella may be the effect of crushing upon an elastic shell. 

Specijic relations._:_The Orbiculoidea discus of Hall was originally compared with the 

Discina (Orbicula) forbesii of Davidson.2 This last-named species, from the Wenlock shales 

and limestones and the Woolhope beds, has, however, a very gibbous pedicle valve and belongs 

.to the genus Schizotreta. A much closer relationship exists between 0. discus I-Iall and a.· 

bainii Sharpe, as is sho'Yll by the following references: 

1846. Orbicula sp. Morris and Sharpe, Geol. Soc. L<?ndon Quart. Jour., vol. 2, p. 277, pl. 10,. fig. 5. 

Devonian (?): Falkland Islands. 

1856. Orbicula bainii. Sharpe, Geol. Soc. London Trans., 2d ser., vol. 7, p. 210, pl. 26, figs. 20-23. 

Black schist: Gydow Pass (with Littori.na). 

Soft, light-colored argillaceous rock: Hottentots Kloof (with Strophomena bainii). 

Dark-colored nodules: Cedarberg (with Chonetes). 

. All in South Africa; occurs also in Falkland Islands.' 

1893. Di8cina bainii. Von Ammon, Gesell. Erdkunde Berlin Zeitschr., vol. 28, p. 359, fig. 4. 

Devonian: Taquarassu, Matto Grosso, Brazil. . 

1897. Orbiculoidea bainii. Schuchert, U. S. Geol. Survey Bull. 87, p. 277. 

"'!\fiddle" Devonian: Falkland Islands; Taquarassu, Matto Gros.so, Brazil; South Africa. 

1905. Orb?:culoidea bainii. Reed, South African Mus. Annals, vol. 4, pt. 3, Iio. 7, p. 168, pl. 20, fig~. 4, 5. 

Bokkeveld beds (Devonian): North of Whipperthal and at Gartila Poort, South Africa. 

It is in fact by no means certain that 0. discus and 0. bainii are distinct. Both species · 

are large and subcircular in outline or a trifle longer than wide; both have the same convex 

brachial valve with excentric beak, concave posterior slope, and height equal to one-third ·the 

width; in both the pedicle val_ve is slightly concave, with an excentric, large, oval, depre~sed 

pedicle opening connected by a narrow slit with· the posterior margin;, finally, the peculiar 

surface and interior markings of the shells are the same in both. If these two species are 

identical, the specific name bainii (1856) has priority over discus (1859) and will have to' be 

adopted. Apparently the only distinction between the two forms is that the beaks are a trifle 

more excentric in 0. bainii than in 0. discus. In the South African species the apex of the 

valves is situated at a distance of one-third to one-fourth the .diameter from the margin, whereas 

in the North American species the beaks are generally subcentral or at most one-third the 

length from the margin. Specimens thus havirig the beak at one-third the diameter from the 

margin 3 may as well be placed under Orbiculoidea discus Hall as under Orbiculoidea bainii 

Sharpe. . . . 

Orbiculoidea montis Clarke, from Grande Grave and Perce Rock, Province of Quebec, is 

similar to the large Chapman fossils, and more abundant material may show that the suspicion· 

of their identity is well founded, but in the fossils from Quebec as figured the brachial valve is 

much higher and conical, the outline is more narrowly elliptical, and, finally, the shells are 

much larger than the Chapman sandstone fo.ssils, the latter being only half the size of Clark's 

speCies. Superfamily CRANIACEA Waagen. 

Family CRANIID.tE King. 

Genus CRANIA Retzius. 

CRANIA sp. indet. 

Plate VI, figure 13. 

A single free brachial valve in internal mold has the following characters: Shell strongly 

convex throughout, spatuloid in outline, widest behind (~);length 12.5 millimeters, maxin1um 

1 This is a Roomerella, not an Orbiculoidea. A specimen in the Cornell University Museum from the Chemung of Pennsylvania distinctly 

shows the concavity of the pedicle valve. · 

2 Soc. geol. France Bull., 2d ser., vol. 5, p. 334, pl. 3, fig. 45, May, 1848. Geol. Survey Great Britain Mem., vol. 2, pt. 1, p. 371, pl. 26, i848. 

British fossil Brachiopoda, vol. 3 (Silurian), p. 73, pl. 7, figs. 14-18. 

a Paleontology of New York, vol. 3, pl. 9, figs. 15, 16a (!'few York); the Maine specimens Nos. 782 and 783; the South African specimens figured 

by Sharpe, op. cit., Pl. XXVI, figs. 21a, 21b, 22, 23, and by Reed, op. cit., pl. 20, fig. 4. 
MOLL USCOIDEA. 25 

width 12 millin1eters, at about two-fifths or one-third the length of the shell from the end, 

height 3 millin1eters. Apex one-third the length from the margin; posterior slope (under part 

of the shell) n1ore convex than the anterior. A scar, which may represent the musculature 

or may be merely a fracture, is quadrangular quadripartite,. extending from the apex half the 

distance to the anterior ( ~) n1argin. Ornamentation indistinct; obscure ipdications of coarse 

radial lines ( ~) or fine plications are visible. 

Locality: Chapn1an sandstone, west side of Edmunds Hill, Chapman Plantation, Aroostook 

County, Maine. 

U. S. National :Museun1, catalogue No. 59692. 

OomJ)(trisons.-This shell has the outline of Schizocrania 0) helderbergice I-Iall and Clarke/ 

but the position of the beaks and greatest convexity are opposite in the two fonns; both are at 

the narrow end in the New York forn1 and at the broad end in the present specimen. 

Orania bellct occurs at Cape Bon Ami, Gaspe, in the Gaspe lin1estone No. 5. The flat pedicle 

valve of this fossil has the apex lllargin:al, which would serve to include the shell in the same 

generic group with Schizocrania ( ?) helilerbergice. It is described by Billings 2 as having the apex 

central and with a concave profile down one side, characters neither of which is observable in 

the Chap1nan specin1en. The New York Oriskany fossil identified with Billings's species and 

figured by Clarke has the beak also central and is much too high in comparison with the Maine 

specimen. Orania bella has no radial sculpture. If the obscure markings of the Maine specimen 

are indications of radial sculptttre the .species may be closely compared with Crania pulchella 

Flail and Clarke. The latter species was originally described from the Lower I-Ielderberg group 

nen.r Clarksville, N. Y., 3 but occurs also in the Oriskanyof Becraft Mountain, Columbia County, 

N. Y. 4 

Order PROTREMATA Beecher. 

Superfamily STROPHOMENACEA Schuchert. · 

Family STROPHOMENIDJE King. 

Genus LEPTOSTROPIDA Hall and Clarke, 1892. 

The genus Leptostrophia was founded by Hall and Clarke for perplane Stropheodontas 

which have the pedicle valve depressed convex, nearly flat; the brachial valve flat or slightly 

concave; and the large musculature in the pedicle valve flabellate, expanding fron1 the beak, 

indistinctly fading in front. The denticulations on the hinge line extend the width of the 

shell. The genotype is Stropheodonta magnifica Hall. 

In this strongly n1arked stropheodontoid genus; which may be easily recognized by the 

flat shell and the large flabellate musculature of the pedicle valve, n1ore than 20 forms regarded 

by their authors as distinct species have been described from the North American Silurian nnd 

Devonian. A list of these species, 5 with their occurrences, follows: 

Clinton-Anticosti: L. prisca Hall, L. julia Billings. 

Cobleskill limestone: L. bipartita Hall, L. nearpassi Barrett, L. textilis Hall (1852, not 1857). 

Acadian nco-Silurian: L. gilpeni Dawson, L. ornatella Salter, L. filosa Sowerby. 

Helderbergian: L. JJlanulata Hall, L. becki Hall. . 

Oriskanian: L. blainvillei Billings, L. irene Billings L. lincklreni Hall, L. magnifica Hall, L. magniventer Hall, L. oriska.nia Clarke, L. t'ltllia Billings. 

Schoharie and '' Corniferous": L. perplana Conrad, L. crenistria Hall. 

Hamilton: L. fragilis, Hall; L. junia Hall, L. pleuristriata Conrad. 

Tully limestone: L. tulliensis Williams. 

Portage and Chemm1g: L. interstrialis Vanuxem. 

Chemung: L. delthyris Conrad (L. nervosa Hall and authors). 

'Paleontology of Now York, vol. 8, pt. 1, p. 179, pl.•4 G, fig. 35, 1892; from tho Lower Helderberg group, near Clark-·ville, N. Y. 

2 Paleozoic fossils: Geol. Survey Canada, vol. 2, pt. 1, p. 15, fig. 5, 1874. 

a Paleontology of Now York, vol. 8, pt. 1, p. 180, pl. 4, fig. 3, 1892. 

• Clarke, J. 1\L, Now York State 1\lus. 1\lem., vol. 3, p. 58, pl. 8, figs. 16, 18, 1900. 

° For bibliogrnpllic references to such of these names as are not given in the sueee'eding pages, see Stropheodonta and Strophomena in Schuchert, 

Charles, A synopsis of American fossil Bracl1iopoda: U.S. Geol. Survey Bull. 87, 1897. 
26 FAUNA OF THE CHAPMAN SANDSTONE OF MAINE. 

Not all the above names are worthy of specific rank, owing to the high degree of variability· 

attained in some .of the forms. This variability becomes most pro.nounced in the Acadian, late 

Silurian, and in the Helderberg and Oriskany ''species." A close study of the Leptostrophias 

from these formations indicates that the plastievariability developed here prohibits very close 

specific demarcation, and suggests that the Cobleskill L. nearpassi and L. textilis, which are now 

considered synonyms of L. bipartita, should be included together with .L. tullia, L. blainvillei, 

L. orislcania, L. planulata, L. pleuristriata, and L. perplana as a single species, or perhaps as 

varieties of a single species, to which the name L. perplana Conrad is applicable. 

The proposal to unite into a single species these forms, which range from the Cobleskill 

limestone (late Silurian) to the Ithaca shale member of the Portage formation (middle NeoDevonian), requires some explanation. This explanation is found in the fact that specimens 

occurring together at a single locality and there representing apparently a single though plastic 

specific type show the supposedly typical characters of several or all of the "species" listed 

above, from Leptostrophia bipartita to L. perz)lana. Thus there are in the 1\ioose River sandstone 

at Little Brassua Lake, Somerset County, Maine, rather small to medium-sized Leptostrophias 

of the L. orislcania type which have 1,00 or more striations per 25 n1illimeters and the acuteangled musculature (60°) of L. tullia and L. bipartita, but which are without any undulations 

on the surface. Other specimens show the musculature with the angle gradually increasing to 

an obtuse-angled musculature with short curving margins (Leptostrophia cf. L. orislcania); the 

strengthening of the striations in some of the specimens links them with L. blainvillei, L. planulata,· L. ]Jleuristriata, and L. perplana. · · 

The Leptostrophias froin the Moose River sandstone at Little Brassua Lake constitute only 

a small part of the evidence available from Maine and elsewhere to show that Leptostrophia perplana and the synonyms listed above represent .only a single variable species having unfixed 

combinations of characters which, were they sufficiently fixed, might rank as of separate specific 

value. These characters include angle of musc;ulature, whether acute, right, or obtuse; muscuh1ture, short or half the length of the shell; marginal septa, shqrt or half the length; strire, 70 

to 80, or 95 to 100, or more, per 25 millimeters; umbones smooth or striate; shell small, medium, 

or large sized; concentric undulations obscure or absent; shell flat or appreciably convex. 

A study of the characters themselves shows that they intermingle and interlink in nearly 

every combination; and study of the stratigraphic range of these combinations supports the 

contention that Leptostrophia bipartita, L. perzJlana, and the rest represent only a single species. 

Characteristic specimens of L. bipartita, a Cobleskill "species," occur in the Moose Ri'ver fauna, 

at Little Brassua Lake, Somerset County, Maine; and a hardly distinguishable type is represented in the Cornell University collections from the Onondaga ("Corniferous") lin1estone 

near Buffalo, N. Y. The type described as L. pleuristriata Conrad fron1 the upper Ilamilton at 

Delphi, N. Y., is specifically indistinguishable fron1 broad musculatured forms of L. planulata 

from the Coeymans (''Lower Pentan1erus ") limestone of the Helderberg group. 

The name Leptostrophia perzJlana (Conrad) not only has priority over aU the others, but 

the type for which it was originally used by Conrad himself best interprets or represents the 

more frequent expression of the "species" of this group .. The name Leptostrophia perplana 

(Conrad) will therefore include the following: Leptostrophia textilis Hall, L. nearpassi Barrett, 

L. bipartita Hall,. L. tullia Billings, L. orislcania Clarke, L. perplana Conrad (and in part of 

authors), and L. pleuristriata Conrad. The species will, however, not include such forms as 

Leptostrophia interstrialis var. delthyris Conrad (the Leptostrophia perplana var. nervosa of 

authors); L. crenistria Hall, and L. fragilis Hall, which have hitherto been identified with 

Conrad's L. perplana. 

This group of species of Leptostrop4ia is a good illustration of the phenomenon to which 

Vaughan 1 recently called attention in proposing the term "gens" or species group for "the 

aggregate of all the species which possess in c01;nmon a large number of essential properties 

and ~re continuously related either in space or time." The important part of the phenomenon, 

which modifies the current conception of the law of the transmission of characters in heredity, 

1 Vaughan, Arthur, On the paleontological sequence in the Bristol area: Geol. Soc. London Quart. Jour., vol. 61, p. 183, May, 190.'>. 
0 

MOLL USCOIDEA. 27 

is tho fn.ct thn.t the characters which serve the systen1atjst in .his discrimination of species 

fluctuate in the same n1anner as those used for discriminating vn.rieties and, secondly, they 

contjnue to fluctuate in successive generations of reproduction. 

LEPTOSTROPHIA PERPLANA (0onrad). 1 

Plate VIII, figures 1-7, 13-16; Plate XI, figure 17. 

1837. "Proclucti." Jackson, J7irst report on the geology of Maine, p. 128, pl. 1, fig. 7. 

"Graywack" [probably :Moose JUver sandstone: Somerset County]: Maine. 

1842. St·ro]Jhomena ]Jerplana. Conrad, Acad. Nat. Sci. Philadelphia Jour., vol. 8, p. 257, pl. 14, fig. 11.. 

Corniferous limestone: Schoharie, N.Y. 

1842. Strophomena ple'Uristriata. Conrad, idem, p. 259. 

"Silurian" [Hamilton formation, or perhaps Ithaca shale member of the Portage formation]: Near Smyrna, 

Chenango County, N.Y. , 

?18,16. Ortkis concinna. :Morris and Sharpe, Geol. Soc. London Quart. Jour., vol. 2, p. 275, pl. 10, fig. 2. 

Lower Devonian: Falkland Islands, South America. 

1852. Leptmna sp. Hall, Paleontology of New York, vol. 2, p. 326, pl. 74, figs. 3a, 3b. 

Le]Jltena bi]M·tita. Hall, idem, p. 326, pl. 74, figs. 4a, 4b, 5a. 

Stro]Jhodontatextilis. Hall, idem, p. 327, pl. 74, figs. 6a-6d. 

All from the Coralline [Cobleskill] limestone: Schoharie, N. Y. 

1859. St1'0]Jhodonta plan-nlata. Hall, Paleontology of New York, vol. 3, p. 184, pl. 16, figs. 9-12. 

Pentamerus [Coeymans] limestone [of Helderberg group]: Schoharie, Dry Hill, and Litchfield, N.Y. 

1859. St·rozJhomena ~ipartita. Hall, New York State Cab. Nat. IIist. Twelfth Ann. Rept., p. 82. 

Coralline [Cobleskill] limestone: Schoharie, N. Y. 

18G3. StrO]Jhomena ]Jer]Jlana. Billings, Portland [Maine] Soc. Nat. Hist. Proc., vol. 1, pt. 2, p. 109. 

Lower Helderberg: Square Lake, Aroostook County, Maine. 

18G3. StrozJhomena JJerzJlana. Billings and Logan, Geology of Canada; pp. 393, 410, 439. 

Gaspe (Oriskany) limestones: Whitehead, Perce Rock, and Cape Barry, Gaspe, Quebec. 

Gaspe sandstone (Oriskany): Douglastown River, Gaspe, Quebec. 

1863. StrO]Jhomena blainvillei. Billings, idem, p. 398. 

Gaspe sandstone: North side of inner basin, Gaspe, Quebec. 

1867. St·ro]Jhodonta ]Jerplana (pars). Hall, Paleontology of New York, vol. 4, pp. 92-98, pl. 11., fig. 22 (not pis. 12, 

17, nor(?) 19). 

Schoharie grit: Clarksville and Knox, Albany County and Schoharie, N.Y. 

Corniferous limestone: Helderberg :Mountains; Schoharie; and at Williamsville, Clarence Hollow, and Cherry 

Valley, in Erie County, N. Y.; Louisville, Ky.; Columbus, Ohio; falls of Ohio River, in Indiana. 

Hamilton group: Eastern New York. Not('?) Cayuga and Seneca lakes, :Moscow, York, Pavilion, Darien, and 

Eighteenmile Creek, N. Y.; Rock Island, Ill.; nor New Buffalo, Iowa [ L. crenistria Hall and L. ]ragilis Hall]; 

not Chemung group at Chemung Narrows, N.Y.', nor along the line of the Blossburg [Erie] Railroad, etc. 

[L. interstrialis var. delthyris Conrad]. 

1868. Stt·ophomena (Stropheodonta) sp. Meek and Worthen, Illinois Geol. Survey, vol. 3, p. 412, pl. 9, fig. 6. 

Yellow sa.nclstone (age of Schoharie grit): Four miles· west of Jonesboro, Union County, Ill. 

?1874. StrO]Jhomena perplana. Nicholson, Paleontology of the Province of Ontario, p. 64, fig. 20. 

Corniferous limestone: Port Colborne and vVainfleet, Ontario. 

1874. St1·ozJhomena blainvillei. Billings, Paleozoic fossils, vol. 2, pl. 3, fig. 1. 

Lower part of Gaspe sandstone: Gaspe, Quebec. 

1874. Strophomena tullia. Billings, idem, pt. 1, p. 29, pl. 2, figs. 6, 6a. 

Lower Devonian: Mount .Toli and Perce Rock, Gaspe, Quebec. 

1877. StrO]Jhodonta ]Jla.niulata .. Barrett, Am. Jour. Sci., 3d ser., vol. 13, p. 386. 

Lower Helderberg trilobite beds [uppermost Helderberg]: Bennett's quarry, near Port Jervis, N.Y. 

1878. StrozJhodonta nearpassi. Barrett, idem, vol. 15, p. 372. 

Coralline limestone [Cobleskill]: Nearpass Bluff, Montague, N.J. 

• l f, as seems possi!)lc, some of the European Leptostrophias, partic~Jlarly Lept:l'na (Leptostrophia) explanata Sowerby and authors, are to ho 

united with I.C])to~trophia per7)lana (Gonrad), it is l~elieved that Conrad's sperific name ought to be retained. Conrad's name was proposed in his 

nrtlelo road before tho Philndolphia Academy of Natural Sciences January 18, 1842, and tho article was published certainly in JR42. Sowcrhy's 

spocios was described in an appendix to the long article of JJ'Archiac and De Verneuil on the Rhenish Lower Devonian deposits, read before the 

1.-ondon Geological Society Docomher 15, 1841; hut whether Sowerby's appendix "'as incorpomted with the original paper of D' Archiac and De 

Vernouil, or whether it was added subsequently, is unknown, though several indications point to the latter supposition. At any rate tho article 

wns not published before 1842, and possibly not before 184fi, as the latter date is printed on the published whole volume of tho "'l'ransactions" in 

which Soworhy's descriptions appeared. Most authors, however, gh·e the date 1842 forD' Archiac and Do Vorneuil's paper. In view of tho longostabllshod reputation of the Philadelphia academy for tho prompt publication of its papers, and th9 fact that·Conrad's article is known to have 

boon published early in 1842, it would appear equitable that Conrad's name l.Je preferred over Sowerby's. 
28 FAUNA OF THE CHAPMAN SANDSTONE OF MAINE. 

1879. Strophodonta perplana. Rathbun,! Boston Soc. Nat. Hist. Proc. vol. 20, p. 25. 

Lower Devonian: Rio Maecuru and Rio Curua, Para, Brazil. 

1883. Strophodonta perplana (pars). Hall, New York State Geologist Second Ann. Rept., pl. 46, figs. 2, 3, 10?, 11 ?, 

12? (not 4-9, 13). 

Corniferous limestone and (?)Hamilton group: Western New York. 

1883. Strophomena perplana. Ells, Canada Geol. Survey Rept. Progress for 1880-1882, ·p. 7 DD. 

Lower Gaspe limestones (Helderberg): Upper part of Griffin Cove River near forks of Ruisseau de la Grande 

· Carriere, Gaspe,· Quebec. 

1883. Strophomena blainvillei. Ells, idem, pp. 8 DD, 14 DD. 

Upper Gaspe limestone: Perce Rock. 

Lower Gaspe sandstones: York and Dartmouth rivers and near Gaspe village, Gaspe, Quebec. 

1885. Stroplwrnena blainvillei. Ells, idem, for 1882-1884, pp. 24 E, 30 E. 

Lower Gaspe limestone (Lower Helderberg): Ruisseau de la Grande Carriere near Griffins Cqve. 

Gaspe Oriskany [whether sandstone or limestone is not stated]: Hills in the rear of Gaspe village, 'Quebec. 

1886. Strophodonta plamtlata. S. G. Williams, Am. Jour. Sci., 3d ser., vol. 31, p. 1~2. 

Lower Helderberg [Coeymans limestone]: Oriskany Falls, N. Y. 

1889. Strophodonta perplana. Nettelroth, Kentucky fossil shells, p. 147, pl. 18, fig. 17. 

Upper strata of the Devonian limestone: Falls of the Ohio in Kentucky and Indiana. 

1889. Stropheodonta perplana. Schuchert, New York State Geologist Eighth Ann. Rept., p. 52. 

Oriskany: Cayuga, Ontario. · 

1890. Stropheodonta perplana. Clarke, Mus. nac. Rio de Janeiro Arch., vol. 10, p. 153. 

Devonian sandstones: Rio Maecuru and Rio Curua, Para, Brazil. 

1890. Strophodonta perplana. Lesley, Pennsylvania Second Geol. Survey Rept. P4, p. 1116, figs.: 

Corniferous ~nd Marcellus limestones: Centre Mills and Pine Grove, Perry County, Pa. 

Hamilton shale: Bells Mills, Blair County, Pa. 

Hamilton upper shales: Perry, Blair, and Huntingdon counties, Pa. 

Cardiola shale: Newport Narrows, Perry County, Pa. 

Chemung: Middle Ridge, Perry County, Pa. 

Stony Brook beds? ("Upper Chemung"): Bloomsburg, Columbia County, Pa. 

1890. Strophodonta perplana (?). Derby, Mus. nac. Rio de Janeiro Arch., vol. 9, p. 75. 

(Middle?) Devonian sandstone: Chapada, 30 miles northeast of Cuyaba, Matto Grosso, Brazil. 

?1891. Strophodonta perplana. Beecher, Am. Jour. Sci., 3d. ser., vol. 41, p. 357, pl. 17, fig. 17. 

Hamilton: Falls of Ohio River. 

not 1891. Strophodonta perplana. Whiteaves, Contributions to Canadian paleontology, vol. 1, p. 220 [probably L. 

junia]. Devonian (upper Hamilton?): Vermilion Falls, Peace River, Canada. 

1892. Strophomena sp. Ulrich. Neues Jahrb. Beilage Band, vol. 8, p. 70. 

Fine-grained light-gray graywacke: Between Pulquina and Agua Blanca, Bolivia. 

Yellow sandstone: Between Totora and Chalhuani, Bolivia. 

Both localities in the lela shale, containing Leptocreliajlabellites. 

1892. Stropheodonta (Leptdstrophia) perplana. Hall and Clarke, Paleontology of New York, vol. 8, pt. 1, p. 288, pl. 15, 

figs. 2, 3, ?10-12 (not figs. 4-9, 13). 

Corniferous limestone, and ?Hamilton group: western New York. 

1892. Strophodonta (Leptostrophia) textilis. Hall and Clarke, idem, p. 288. 

Coralline [Cobleskill] limestone: New York. 

1892. Stropheodonta (Leptostrophia) blainvillei. Hall and Clarke, idem, p. 288. 

Gaspe sandstone: Gaspe, Quebec. 

1892. Stropheodonta (Leptostrophia) tullia. Hall and Clarke, idem, p. 288. 

Lower Devonian: Gaspe, Quebec. 

1892 {Leptostrophia cf. becki. Clarke, Am. Jour. Sci., 3d ser., vol. 44, p. 413. 

· Leptostrophia cf. perplana. Clarke, idem. · 

Oriskany siliceous limestone: Becraft Mountain, Columbia County, N. Y. 

1897. Stropheodonta, (Leptostrophia) blainvillei. .Schuchert, U. S. Geol. Survey Bull. 87, p. 420. 

Lower Devonian: Gaspe, Quebec. 

1897. Strophodonta nearpassi. Schuchert, idem, p. 425. 

Coralline limestone: Near Port Jervis, N. Y.; in New Jersey. . 

1897. Stropheodonta planulata. Scpuchert, idem, p. 426. 

Lower Helderberg: Schoharie, Dry Hill, and Litchfield, N.Y. 

1897. Stropheodonta (Leptostrophia) tullia. Schuchert, idem, pp. 243, 427. 

"Upper Helderberg" (Devonian): Mount Joli and Split Rock, Perce, Gaspe, Quebec. 

1897. Strophornena (?) bipa_rtita. Schuchert, idem, p. 429. 

Coralline limestone: Schoharie, N. Y. 

1 Both Rathbun (1879) and Clarke (1890) note the very large size and variability of these Brazilian Leptostrophias. These features in the United 

Stat(IS and Canada are confined chiefly to the Helderberg and Oriskany(?) forms. 
.. 

MOLL USCOIDEA. 

1897. Stroplteodonta (LeptostrOJJhia) textilis. Schuchert, idem, pp. 243, 427. 

Coralline limestone: Schoharie, N. Y. 

1897. Strophodonta JJerplana. \Veller, Jour. Geology, vol. 5, No. 6, pp. 628, 629. 

Corniferous limestone: Devils Bake Oven, near Grand Tower, Jackson County, Ill. (zones 11, 13). 

1898. Stropheodonta perplana Conrad, Bownocker, Denison Un.iv. Sci. Lab. Bull., vol. 11, pl. 7. 

Corniferous limestone: Ho.rrisburg, Columbus, Marble Cliff, Marion, Kellys Island, and Radnor, Ohio. 

1899. StrOJJheodonta perJJlana. Prosser, New York State Geologist Seve:p.teenth Ann. Rept., for 1897, p. 352. 

Schoharie grit: Near Clarksville, Albany County, N.Y. 

1899. Stropheodonta (Leptostrophia) perplana. Schuchert, Am. Jour.·Sd., 4th ser., vol. 7, p. 432. 

Oriskany chert: Camden, Benton County, Tenn. 

1900. Stropheodonta perplana. Schuchert, Geol. Soc. America BuU., vol. 11, p. 282. 

Becraft limestone: New York. 

?Lower Helderberg: Tennessee, Maine, and New Brunswick. 

Trilobite beds (lower Oriskany): Port Jervis, N.Y. (p. 306). 

Lower Oriskany: Becraft Mountain, N.Y. (p. 307), and Camden, Benton County, Tenn. (p. 322). 

Upper Oriskany: New York; Oneida and North Cayuga townships, Ontario. 

1900. StrOJJheodonta planulata. Schuchert, idem, p. 283. 

Coeymans limestone: New York. 

T...ower Helderberg: Tennessee. . 

1000. Leptostrophia oriskania. Clarke, New York State Mus. Mem., vol. 3, No.3, p. 53, pl. 7, figs. 29-35. 

29 

Oriskany siliceous limestone: Becraft Mountain, Columbia County, N.Y.; along \Vest Shqre Railroad, one-half 

mile southeast of Rondout Creek (p. 74); and at Glenerie, 7 miles north of Kingston, N. Y. (p. 74). 

1903. Stropheodonta biJJartita. Weller, Paleontology of New Jersey, vol. 3, pp. 63-72, 226, pl. 20, figs. 1-5. 

Decker Ferry limestone: William Nearpass quarry (pp. 63-66), and adjoining farm south of Tri-States, 11 miles 

northeast of Hainesville (p. 69); lf miles below Peters Valley (p. 70) Flatbrookville (p. 71); Upper Longwood 

(p. 72); all in New Jersey. 

1903. Stropheodonta JJlanulata. Weller, idem, p. 276, pl. 27, figs. 1, 2. 

· Coeymans limestone (Helderbergian): Nearpass Quarry Bluff, 2 miles northeast of Flatbrookville (p. 84), and 

in E. Harris's pasture below Flatbrookville, N.J. 

1903. StroJJheodonta perplana. Weller, idem, pp. 103, 366; pl. 51, figs. 12, 13. 

Onondaga limestone: Delaware River, 2~ miles below Tri-States; also 1~ miles southwest of Peters Valley, N.J. 

1903. Stropheodonta bipartita and S. textilis. Hartnagel, New York $tate Mus. Bull. 69. 

Cobleskill limestone: Steven's farm, 3 miles east of Schoharie (p. 1117); extreme north end of West Mountain. 

Schoharie (p. 1124); and half a mile northwest of Carlisle (p. 1126); Schoharie County. Heard gypsum quarry 

1 mile south of Lyndon; Onondaga County (p. 1161). Frontenac Island, Cayuga Lake (p. 1133). Also in 

western New York (p. 1128). 

Wilbur limestone: Old cement mines, Rondout, N.Y. 

1903. Leptostrophia cf. L. planulata. Van Ingen and Clark, idem, pp. 1188, 1206. 

Coeymans liniestone: Near Rondout, N.Y. 

1903. Leptostrophia oriskania. Van Ingen and Clark, idem, pp. 1203, 1206. 

Oriskany: Glenerie and Rondout,_ N.Y . 

1903. Leptostrophia perplana. Van Ingen and Clark, idem, p. 1205. 

Corniferous limestone: About Kingston, N.Y. 

?1903. Stropheodonta cf. concina. Reed, South African Mus. Annals, vol. 4, p. 169, pl. 20, fig. 6. 

Lower Devonian: Warm Bokkeveld, South Africa. 

1905. Leptostrophia t7.tllia. Clarke, New York State Mus. Bull. 80, pp. 143, 145. 

Perce limestone: Perce Rock, Gaspe, Quebec. 

1905. Leptostrophia blainvillii. Clarke, idem, p. 145. 

Gaspe sandstone: Gaspe, Quebec. 

1905. Leptostrophia or·iskania. Clarke, idem, pp. 145, 152. 

Grand Greve limestone: North shore of Gaspe Bay, Quebec. 

1905. Leptostrophia oriskania. Shimer, idem, pp. 185, 227, 240, 264. 

Dalmanites dentatus zone, or trilobite beds (lower Oriskany): Trilobite Mountain, N. Y. 

1905. Stropheodonta bipartita. Hartnagel, idem, pp. 351, 352, 354. 

Decker Ferry limestone, lower part: Fiddlers Elbow on Delaware & Hudson Canal, Orange County, N.Y. 

Decker Ferry limestone, upper part: Along New York, Ontario & Western Railway (Kingston branch), one-half 

mile southwest of Accord, and on the Cuddeback farm, Cuddebackville, Orange County, N.Y. 

Cobleskill limestone: Old quarry, 1 mile southeast of Cuddebackville, Orange County, N.Y. 

1905. Stropheodonta cf. S. planulata. · Williams and Kindle, U.S. Geol. Survey Bull. 244, pp. 28, 47. 

Top of Hancock limestone (Lower Helderberg fossils): East fork of Powell River, just above flouring mill, Bigstone Gap, Wise County, Va. 

1907. Leptostrophia tardifi. Clarke, New York State Mus. Bull. 107, p. 273, figs. 

Lower Devonic: Perce Rock, Quebec. 

1907. Leptastrophia magnifica parva. Clarke, idem, p. 274, figs. 

Lower Devonic: Edmunds Hill, Chapman, Aroostook County, Maine. 
30 FAUNA OF THE CHAPMAN SANDSTONE OF MAINE. 

Shell wider than long; length varying from three-fourths the width to nearly equal to the 

width; front of the shell arcuate, curving into the sides, which are·slightly rounded, subparallel, 

and frequently slightly converging toward the hinge line. Hinge extremities auriculate or 

angular; rarely mucronate, and then only slightly so. Hinge straight; cardinal line in the pedicle 

valve slightly reclining from the beaks. Greatest width of shell along hinge line; in forms where 

the sides converge toward the hinge the greatest width is about midway the length of the shell. 

Pedicle valve depressed convex, brachial valve flat· or concave. Greatest elevation of the 

shell is in the pedicle valve over the nniscular area, a varying distance posterior to the middle. 

This maximum elevation is from one-eighth to one-fourteenth the width of the shell. Musculature of pedicle valve fan shaped, spreading from the beaks, rarely extending forward beyond 

the mid-length of the shell; not discernably cordate or insinuate in front. On each side of 

the muscular scar are defining ridges, which are generally pustulose; they extend from the beaks 

varying distances forward but not more than midway to the front, becoming gradually obsolescent forward. The angle formed by the defining ridges or outer edges of the musculature 

varies from acute (55°) to obtuse (125°). A thin, blunt median septum or ridge extends the 

length of the musculature, becoming thick and broad for about 2 millimeters under the beak: 

No scar of the diductor muscles is discernible in the pedicle valve. Between the hinge line 

and the sides of the musculature the inner surface of the pedicle valve is strongly pitted, the 

pitting becoming less conspicuous on approaching the hinge line. 

The interior of the brachial valve shows the cardinal process strongly bilobed from its 

origin" outward; internal· casts of the brachial valve show it as two deep holes in front of the 

hinge line. These holes are somewhat elongate, reniform in outline, and nearly parallel. On 

the forward side of the base of the cardinal process, two diverging elevated ridges proceed.outward, gradually flattening down to the level of the interior of the shell. Between these ridges, 

in a central position, a blunt septum extends forward a short distance. 

The cardinal area of the pedicle valve is narrow, though quite apparent. The cardinal area 

of the brachial valve is linear or absent. 

The surface is marked by fine, distinct, radiating, raised lines which are nearly uniform 

in size and strength over the whole surface; they are rounded or subangular, and straight or 

slightly flexuous on the body of the shell, but slightly curving near the hinge· extremities. The 

lines increase freely, mainly by implantation, and at a distance of 20 millimeters from the beak 

number in the typical forms about 70 per 25 millimeters, though they vary fron1 60 to 100 or 

more in this distance in the varietal modifications. Obscure concentric undulations are often 

developed on the surface; but these are generally very obscure, and in exfoliated shells are 

seldom if ever discernible. More commonly, however, traces of them as oblique wrinkles may 

be observed near the hinge line. 

The diagnostic characters by which this very variable species may be recognized are (1) the 

fine, slightly uneven, flexuous surface lineations, finer than. in L. beckei, and not granulose nor 

so flexuous or distant as in L. crenistria, the lines subequal and not less than 60 per 25 millimeters; (2) 'the small musculature extending less than two-thirds the length of the shell and 

generally less than half; (3) the absence of any cordate insinuation in front of the musculature; 

(4) a strongly bilobed cardinal process, leaving two de.ep reniform holes in the· internal mold of 

the brachial valve; the holes being only very slightly divergent and nearly parallel. 

Remarks on the Maine specimens from the Moose River sandstone are given in the followi:pg paragraphs. 

Figure 1 of Plate VIII shows an internal mold of a large pedicle valve, preserving also a 

fragment of shell, length 34 millimeters; the greatest width, 45 millimeters, is. two-fifths the 

length from the hinge. Sides rounded, converging toward the hinge; depth of valve, 3.4 millimeters; musculature obtuse, 115°; radiating lines flexuous, increasing by implantation, ·but 

largely also by bifurcation; at 25 millimeters from the beak there are near the middle about 

13 lines per 5 millimeters, and the furrows between the lines are deeply pitted. No undulations. This is a typical large specimen of L. blainvillei (Billings). 

.. 

.. 
.... 

\ 

J 

• 

MOLL USCOIDEA. 31 

FiguTe 17 of Plate XI resembles the form just described, but has obscure undulations on 

the internal1nold. At a distance of 20 to 25 n1illimeters fron1 the beak 12 rn,diating lines were 

counted in 5 millin1eters at the front, and 18 lines in the same space on the side of the shell; 

furrows between the lines are pitted .. This specimen combines characters of L. blainvillei and 

L. o1'islcania and of a Leptostrophia fron1 the Onondaga limestone at Buffalo, N.Y. 

Another un:figured brachial valve is in length 18 millin1eters; nearly flat. A low median 

ridge or narrO\v platfonn extends half the length of the shell; two sin1ilar, shorter ridges or plat-

. for1ns diverge from the beak, one on each side of the n1edian line. The radial lines increase 

by bifurcation; 15 may be counted in a width of 5 millimeters at a distance of 15 millimeters 

fro1n the beak. There are no concentric undulations. 

A large typical specimen of LeptostroJJhia magnijica I-Iall from the collections of Mr. Harold 

Prince exhibits an elongated outline; length, 36 millimeters; width the same. · The musculature 

boundaries diYerge at an angle of 85° to 90°; the scars extend tillee-fifths the length of the shell· 

and are diYisible into four conspicuous strap-shaped portions, or "lingules." The surface lines 

are sharply elevated, and closely set in. internal molds, but as preserYed on the exterior they 

are low and rounded; 19 lihes may be counted in a space of 5 millimeters at a distance of 30 

n1illin1eters fro1n the beak; they increase by bifurcation and implantation. Occasionally a 

finer line alternates with the coarser normal lines over small portions of the surface, "si1nulating 

the ornmnentation of the Silurian Leptostrophia filosa (Sowerby). A couple of very obscure 

concentric undulations are discernible near the front of the musculature . 

. This large, elongate, finely lineate Leptostrophia, with the acute and very long musculature, is identifiable with Hall's Leptostrophia magnijica, a characteristic Oriskany type. (Compare the specin1en described with L. magnijica from the Oriskany of New Jersey. 1) The chartteteristically Oriskany type of Leptostrophia magnijica as it occurs in the Moose River sandstone ftuina (which contains Spirifm· arenosus, Spirijer murchisoni, Leptocmlia .fiabellites, and 

other characteristic Oriskany horizon markers) does not appear to be connected by any transitional gradations with the accompanying Leptostrophia blainvillei Billings and L. perplana 

Conrad. This has been the chief reason for considering L. magnijica as a distinct species. 

Apart fron1 the large size of the shell, the large musculature is of itself by no means a characteristic deYelopn1ent of Oriskany time, for there occurs in the Manlius limestone or in the lower . 

part of the oYerlying I-Ielderberg at Litchfield, N. Y., a large n1usculatured Leptostrophia not 

011sily distinguishable from L. magnijica. 

Specin1ens from the Chapman sandstone at Edmunds Hill are described below. 

Figure 3, Plate VIII, represents a large pedicle valve in internal mold; length 35 milliIneters, width 40 millimeters, boundaries of musculature form obtuse angle (125°) and extend 

slightly beyond half the length of the shell, having 7 or 8 "lingules" each side of the middle; 

surface radial lines 14 to 15 pm• 5 millin1eters at a distance of 30 millimeters from the beak; 

the furrows between the lines seen1 to be pitted in the better-preserved spots of the shell. No 

undulations. This specimen is a large L. blainvillei in forn1 but is also similar, except for the 

obtuae 1nusculature, to some specin1ens of L. planulata found at Jerusalem Hill, Litchfield, 

N. Y., in the Coeymans ("Pentamerus") limestone of the I-Ielderberg group. 

Figure 7, Plate VIII, shows ·a smaller specimen· with similar ornamentation. It is 25 

millimeters wide and h~s an acute musculature (80°-85°). Type of L. planulata and JJleuristria. 

Figure 13, Plate VIII, represents an external mold of a pedicle valve; length 25 millimeters, 

width 27 1nillimeters; extreme width along hinge 30 millimeters; sides of shell curved, converging toward hinge; hinge extremities sharply auriculate. Boundaries of musculature 

apparently acute (85°). Radial lines increase by implantation, 22 in a space of 10 millimeters 

at a distance of 25 millimeters from beak. One or two very obscure wrinkles near middle of 

shell; stronger, more numerous short ohijque wrinkles along the hinge line. No traces of pits 

between the elevated lines. This shell combines characters of L. ~ullia and L. planulata and in 

the coarse radial lines approaches L. becki. It fairly. represents a typical specimen of L. 

planula,ta, I-Iall. 

1 Welier, Stuart, Paleontology of New Jersey, Paleozoic fauna:.,, p. 345, pl. 45, figs. 10, 11, 1903. 
32 FAUNA OF THE CHAPMAN SANDSTONE OF MAINE. 

Figure 15, Plate VIII, is similar to the last specimen, but is larger, being 30 millin1eters 

· long. 

Figure 6, Plate VIII, represents a small pedicle valve in internal mold, n1usculature acute 

(55°), extending less than half the length of the shell; radial lines 25 in 8 millimeters at a distance of 15 milli1neters fron1 the beak, furrows between the lines pitted. Width of specin1en 

about 30 milli1neters. The acute angle of the musculature boundaries is sin1ilar to that of 

L. tullia and L. bipartita,. and the nun1ber of radial lines is n1idway between the two. 

Figure 14, Plate VIII, is a· large pedicle valve in external mold; length 35 millin1eters, · 

width 38 millimeters.: sides rounded and converging toward the hinge line. Boundaries of 

musculature n1ake acute angles, apparently about 60°. Surfac·e radial lines ~crease by 

implantation; 12 in the space of 5 millimeters at 15 millimeters f1on1 the beak. Furrows 

between the elevated lines apparently pitted. Over several parts of the surface the radial 

lines seem to alternate, a finer one being implanted between each pair of norn1al lines (cf. 

L. filosa Sower by). More than half a dozen obscure uneven undulations are barely visible. 

This shell is very close to L. tullia Billings and L. planulata Hall. 

Locality: Chapman sandstone, west side of Edmunds Hill (common), Edmunds Hill (occasional), Presque Isle Stream (occasional), Aroostook County, Maine. Moose River sandstone, 

Parlin Pond (rare), Little Brassua Lake (abundant), Somerset County, Maine. 

U.S. National Museun1, catalogue Nos. 59693, 59694, 59695, 59696, 59697. 

Genus LEPTlENA Dalman, 1828. 

LEPT..<EN A RHOMBOIDALIS (Wilckens). 

Plate VIII, figures 8-12. 

1769. Conchita rhomboidalis. Wilckens, Nachricht von selten Versteinerungen, p.77, pl. 8, figs. 43, 44. 

1841. Strophomena undulosa. Conrad, New York Geol. Survey Fifth Ann. Rept., p. 54. 

1842. Strophomena depressa. Vanuxem, Geology of New York, Rept. Third Dist., p. 79, fig. 5, 

1842. Strophomena 'l.tndulatus. Vanuxem, idem, p. 139, fig. 3. 

1843. Strophomena depressa. Hall, idem, Rept. Fourth Dist., p. 77, fig. 5; p. 104, fig. 2. 

1843. Strophomena undulata. Hall, idem, p. 175, fig. 3. 

1843. Productus? sulcatus. Castelnau, Essai sur le systeme Silurien d'Amerique septentrionale, p. 39, pl. 13, fig. 7. 

1843. Productus silcifer. De Verneuil, idem, p. 39. 

1847. Strophomena undulata. Yandell and Shumard, Contributions to the geology of Kentucky, p. 11. 

1847. Leptmna tenuistriata. Hall, Paleontology of New York, vol. 1, p. 108, pl. 31A, fig. 4. 

1852. Leptrena depressa. Hall, idem, vol. 2, p. 62, pl. 21, fig. 8; p. 257, pl. 53, fig. 6. 

1856. Strophomena depressa. Billings, Canadian Nat. Geol., vol. 1, p. 59, pl. 1, fig. 5 .. 

1858. Leptmna depressa. Rogers, Geology of Pennsylvania, vol. 2, pt. 2, p. 823~ fig. 630. 

1859. Strophomena rugosa. Hall, Paleontology of New York, vol. 3, p. 195, pl. 19, fig. 1. 

1860. Strophomena depressa. Roemer, Silurian fauna of western Tennessee, p. 65, pl. 5, fig. 2. 

1861. Strophomena rhomboidalis. Billings, Canadian Jour.,_ vol. 6, p. 336, figs. 111, 112. 

1863. St1·ophomena rhomboidalis. Billings, Geology of Canada, p. 311, fig. 314; p. 367, fig. 373. 

1863. Strophomena rhomboidalis. Billings; Portland Soc. Nat. Hist. Proc., p. 107, pl. 3, fig. 1. 

1863. Strophomena analoga. Davidson, Geol. Soc. London Quart. Jour., vol. 19, p. 173, pl. 99, fig. 18. 

1865. Leptmna quadrilatera. Shaler, Mus. Comp. Zool. Bull. 4, p. 65. 

1867. Strophomena rhomboidalis. Hall, Paleontology of New York, vol. 4, p. 76, pl.12, figs. 16-18; p. 414, pl. 15, figs. 

15, 16. 

1868. Strophomena rhomboidalis. Meek a.nd Worthen, Illinois Geol. Survey, vol. 3, p. 426, pl. 10, fig. 7 

1873. Strophomena rhomboidalis. Meek, Paleontology of Ohio, vol. 1, p. 75, pl. 5, fig. 6. 

187 4. Strc phomena rhomboidalis. Billings, Paleozoic fossils, vol. 2, p. 27. 

1874. Strophomena gibbosa. James, Cincinnati Quart. Jour. Sci., vol. 1, p. 333. 

1875. Strophomena 'rhomboidal,is .. White, U. S. Geog. Surveys W. 100th Mer., vol. 4, p. 85, pl. 5, fig. 5. 

1875. Strophomena tenuistriata. Miller, Cincinnati Quart. Jour. Sci., vol. 2, p. 55. 

1877 . .Strophomena rhomboidalis. Hall and Whitfield, U. S. Geol. Expl. 40th Par., vol. 4, p. 253, pl. 4, fig. 4. 

1878. Strophornena analoga. Dawson, Acadian geology, 3d ed., p. 295, fig. 95. 

1879. Strophomena rhomboidi:tlis. Hall, New York State Mus. Nat. Hist. Twenty-eighth Rept., p. 151. pl. 22, figs. 4-10.· 

1881. Strophomena rhomb01:dalis. Miller, Cincinnati Soc. Nat. Hist. Jour., vol. 4, p. 1. 

1882. Strophomena rhomboidalis. Hall, Indiana State Geologist Eleventh Rept., p. 288, pl. 22, figs. 4-10. 

.... 
MOLL USCOIDEA. 

Hall, New York State Geologist Second Ann. Rept., pl. 3&, figs. 17--31. 

Hall, idem, pl. 38, figs. 12-16. 

33 

1883. StrOJ)hom,ena rhontboidalis. 

1883. StrOJ)homena temtistriata. 

1884. Strop/wmena rhomboidal·is. 

1889. StrOJ)homena rhomboidalis. 

1889. StrOJ)homena rhomboidalis. 

Walcott, U. S. Geol. Survey Mon. 8, p. 118. 

Beecher and Cl;trke, New York State Mus. Mem., vol. 1, p. 18, figs. 1-13. 

Nettelroth, Kentucky fossil shells: Kentucky Geol. Survey Mem., p. 150, pl. 18, 

figs. 1-3. 

1890. St?'OJ>hom,ena rhomboidal·is. Foerste, Boston Soc. Nat. Hist. Proc., v'ol. 24, p. 298. 

1891. Strophomena rlwmboidalis. Beecher, Am. Jour. Sci., 3d ser., vol. 41, p. 357, pl. 17, figs. 18-21. 

1892. LeJ>lmna tenuistriata. Hall and Clarke, Pitleontology of New York, vol. 8, pt. 1, pl. 8, figs. 12-16. 

1892. LeJ)lmna rhomboidal·is. Hall and Clarke, idem, vol. 8, pt. 1, p. 279, pl. 8, figs. 17-31; pl. 15A, .figs. 40-42; 

pls. 21-24. 

1892. Leptmna (StrOJ>homena) rlwmboidal7:s. Beecher, Am. Jour. Sci., 3d ser., vol. 44, p. 150, pl. 1, figs. 7-9 .. 

1895. StrOJ>homena rhomboidalis. Herrick, Geology of Ohio, vol. 7, pl. 20, fig. 6. 

1895. Le])trena rhomboidalis. Foerste, idem, vol. 7; p. 566. 

1895. Plectambonites rhomboidalis. Keyes, Missouri Geol. Survey, vol. 5, p. 70, fig. 6. 

The description· of the Maine material representing this species is as follows: 

Shell coi1vex-concave, quadrately semicircular; length varying from three-fourths width to 

equal width. Greatest width along the hinge line. Shell fiat in younger portion, abruptly 

geniculate in ,front. The geniculate portion is short, two-fifths to one-fourth as long as the 

flat portion and bent at about a right angle to it. The fiat portion is covered with strong 

undulations, as Inany as 10 or 11 in about 15 millimeters. These undulations cease where the 

shell becomes bent and are absent on the geniculated portion. Musculature of pedicle valve 

ovnl, about as 'vide as long and extending nearly half the length; deeply sunken into the shell 

and surrounded by_ a raised ridge, formed by the dental lamellre, which curve around the 

musculature, converge, and nearly unite in front. The surface ornamentation consists of 

·radiating flexuous elevated lines, interrupted and variable in strength; on passing over the 

wrinkled portion of the shell the lines may be well developed on the. crest of the wrinkles and 

become obsolescent in the grooves; or, vice versa, the lines may be well developed in the grooves 

and obsolescent on the crests." The geniculate portion of the shell.is 'marked .by radiate lines. 

The lines are about equal to the ip.terspaces. At a distance of 12. millimeters from the beak 

11 have been counted in the space of 3 millimeters. Pmi.ctre or minute canals extend forward 

and outward through the shell substance and are arranged in rows opening exteriorly on the 

elevated radiate lines. 1 

The Chapman specimens are all small, having the following dimensions: 

Dimensions of specimens of Leptmna rhomboidalis. 

Length (millimeters). Breadth (millimeters). 

Height of geniculation (millimeters). Shape of umbonal 

portion. . 

9 13 5 Concave. 

18 19 7! Convex. 

·············· 22 ..................... Convex. 

19 23 4! Flat. 

The geniculation is very abrupt in all the specimens upon which it is visible, so that these 

shells can not possibly be considered to belong to the variety ventricosa Hall. · 

Locality": Chapman sandstone; three pedicle valves found at Edmunds Hill and another 

at west side of Edmunds flill, Chapman Township, Aroostook County, Maine. 

U. S. National Museum, catalogue Nos. 59698, 59699. 

1 Paleontology of New York, vol. 3, pl. 10, fig. 1 L+, 1878. 

50245°--~0.89--16----3 
·. 

34 FAUNA OF THE CHAPMAN SANDSTONE OF MAINE. 

Genus SCHUCHERTELLA Girty, 1906. 

SCHUCHERTELLA · WOOLWORTHANA (Hall). 

Plate III, figure 10. 

1842. Orthis umbraculum [not Schlotheim]. D'Archiac and De Verneuil, Geol. Soc. London Trans., 2d ser., vol. 6, 

p. 396. 

Devonian: Kentucky [not Plymouth, England, nor the Eifel, Germany, nor Ferques, France=O. u?nbraculum 

Schlotheim s. str.]. 

1843. Orthis umbracul·um [not Schlotheim]. F. A. Roemer, Die Versteinerungen des Harzgebirges, p. u; pl. 4, fig. 4. 

(Spiriferen) sandstone: On the Kahleberge and the Schalke, Harz Mountains, Germany [not Gerolstein in the 

Eifel=O. umbraculum Schlotheim s. str.]. _ 

??1843. Orthis vetusta. F. A. Roemer, idem, p. 11. 

Dark limestone [Hercynian]: Hilkenschwende in the Harz, Germany. 

1845. Orthis crenistria [not Phillips]. De Verneuil, Soc. geol. France Bull., 2d ser., vol. 2, p. 458. 

[Upper Eo-Devonian]: Province of Asturias, Spain. 

1846. Orthis sulivani. Morris and Sharpe, Geol. Soc. London Quart. Jour., vol. 2, p. 275, pl. 10, fig. l. 

Lower Devonian: Falkland Islands. 

1850. Orthis devonica [not Keyserling]. De Verneuil, Soc. geol. France ;Bull., 2d ser., vol. 7, p. 161. 

[Upper Eo-Devonian]: Veneros· and Sabero (Leon), Ferrones and Arnao (Asturias), Spain [not Ferques,·France; 

Russia; nor Persia]. · · 

1850. Lept:ena umbraculum [not Schlotheim]. F. A. Roemer, 1 Beitrage zur geologischen Kenntniss des nordwestlichen 

Harzgebirges, p. 105. 

"Upper Silurian"(?) [Hercynian]: Harz Mountains, Germany. 

1850. Orthis umbraculum [not Schlotheim]. Zeiler, Naturh. Ver. preuss. RheinHinde Verh., vol. 7, p. 143. 

Coblentzian graywacke: Coblentz and vicinity, Germany. 

1850. Orthis devonica [not Keyserling]. De Verneuil, Soc. geol. France Bull., 2d ser., vol. 7,·p. 781. 

Devonian [higher Eo-Devonian]: St. Jean-sur-Mayenne, France, and Asturias, Spain (not Ize, Ferques, Vire, · 

Les Courtoisieres, France; Russia; nor Persia). 

1852. Lept:ena vetusta. F. A. Roemer, Beitrage zur geologischen Kenntniss des nordwestlichen Harzgebirges, p. 98, 

pl. 15, fig. l. 

Silurian [Hercynian] limestone: Hilkenschwende, in the Harz Mountains, Germany. 

1853. Orthis hipparionyx [not Vanuxem]. Schnur, Palaeontographica, vol. 3, p. 217, pl. 40, figs. 1a, b, c. 

[Eo-Devonian] lowest limestone beds and graywacke not far below: Priim, iri. the Eifel, Germany. 

1854. Orthis hipponyx. Wirtgen and Zeiller, Naturh. Ver. preuss. Rheinlande Verb., vol. ll, p. 478. 

Rhein graywacke: Lahneck, Niederlahnstein, Rhense, Laubach, Giels, Winningen, Hatzenport, Brodenbach, 

Burgen, Asterstein, and Unkel, Rhenish Germany. · 

1854. Orthis umbraculum [not Schloth3im]. Tschihatscheff, Soc. geol. France Bull., 2d ser., vol. 11, p. 413. 

Rhenan: "Guenkson" Valley, between Alemdagh and Boulgourludagh, Asiatic side of the Bosphorus, Asia 

Minor. 

1856 {Orthis hipparionyx. De Verneuil and Barrande, idem, vol. 12, p. 1016. 

· Orthis devonica. De Verneuil and Barrande, idem. 

Lower Devonian: Puerto del Ciervo, Spain; France; and the Rhine. 

1856. Strophomena sulivani. Sharpe, Geol. Soc. London Trans., 2d ser, vol. 1, p. 209, pl. 26, figs. 18-19. 

Dark-colored schist and reddish argillac:eous rock [Eo-Devonian]: Warm Bokkeveld, South Africa. 

1856. Strophomena bainii Sharpe, idem, p. 208, pl. 26, figs. 13, 17. 

Lower Devonian: Warm Bokkeveld, South Africa. 

1857. Strophomena woolworthana. Hall, New York State Cab. Nat. Hist. Tenth Ann. Rept., p. 48, figs. 

Lower Helderberg [New Scotland] shaly limestone: Albany and Schoharie counties, N. Y. 

1857. Strophomena obovata. Zeiler, Naturh. Ver. preuss. Rheinlande Verh., vol. 14, p. 51, pl. 4, figs. 19-20: 

Sandy graywacke (Lower Devonian): Burgen-an-der-Mosel, Germany. 

Not 1857. Orthis hipparionyx. Krantz, idem, p. 153 [S. umbraculum s. str.]. 

Lower· Devonian: Menzenberg (near Unkel), Germany. 

1858. Leptreiw vetusta. Giebel, Die silurische Fauna des Unterharzes, p. 50, pl. 4, fig. 2. 

"Silurian" [Hercynian] limestone: Magdespn.p1,g an<f Rilkenschwende, in the Harz Mountains, Germany. 

1859. Strophomena woolworthana. Hall, Paleontology. of New York, vol. 3, p. 192, pl. 17, figs. 1, 2. 

Shaly limestone [New Scotland] of the .. Lower Helderberg: Helderberg Mountains, Schoharie, Carlisle, and 

Hudson, N.Y. · 

1860. Streptorhynchus pandora. Billings, Canadian Jour., vol. 5, p. 226, figs. 12, 13. 

Corniferous limestone: Cayuga, Ontario. 

1 This was believed to be identical with Vanuxem's Hipparionyx proximus, but is now regarded as a member of the group of Schurhertella 

sulivanti. It is of enormous size, with rounded shoulders, giving the shell a circular outline. 

-~ 
~-

MOLL USCOIDEA. 

1863. Streptorhynclms pandora. Billings, Geology of Canada, p. 369, fig. 384. 

Corniferous limestone: West of Grand River in Haldemand and Norfolk counties, Canada West. 

1863. Streptorhynchus 'WOOl'Worthana. Billings, idem, p. 957, :fig. 449. 

Lower Helderberg: New York. 

1864. Orthis um.braculum. De Verneuil, Soc. geol. France Bull., 2d ser., vol. 21, p. 151. 

Lower Devonian: Gueuk-sou Valley between Alemclagh and Boulgourladagh, Asiatic Asia Minor. 

1864. Orthis kippario'nyx (?). Davidson, British fossil Brachiopoda, Devonian, p. 90, pl. 17, figs. 8-11. 

:Lower Devonian: :Looe, Cornwa.ll, England. 

. . I 

186(). Orthisina ~t?r1,brac1tlum. F. A. Roemer, Die Versteinerungen des Harzgebirges nach den Formationen geordnet, 

p. 20. 

Spil"iferen sandstone: Kahleberg, Harz Mountains, Germany. 

1866. Ortlt1:s de·vonica.. De Verneuil, in Tschihatscheff, Asie Mineure, Paleontologic (Geologie, pt. 4), p. 34, and 

Appendix, 1869, p. 486. 

Lower Devonian: Near Kartal, Asia Minor. 

1870. Orthis cf. 0. urnbraculurn. Quenstedt, Petrefactenkunde Deutschlands, pl. 56, fig. 35. 

lthenish Lower Devonian: No locality given. 

1870. Ortlt·is strigosa. Quenstedt, idem, pl. 56, :figs. 55, 56. 

Ithenish :Lower Devonian: Lauback Valley, near Coblentz, Germany. 

1871. StreJ)lorhynchus ~trnbraculurn and var. gigas. Kayser, Deutsche geol. Gesell. Zeitschr., vol. 21, pp. 316, 319, 328, 

366, 371. 

Lowest Coblenzian: Between Oberstadtfelcl and Niederstadtfelcl, near baun. 

Aluien-Coblenzian transition graywacke: Waxweiler and Daleiden. 

Coblenzian calcareous lenses: Priim, Hersdorf, and Schonecken. 

Cultrijugatus zone: Elwerath, near Pri.im. 

All localities in the Eifel, Germany. 

?1874. Streptm·hynclms agassizi. Hartt, 1• Buffalo Soc. Nat. Sci. Bull., vol. 1, p. 248, pl. 9, figs. 3, 4, 10, 16, 17, 23, 25, 

26, 28-30. 

:rvt:iddle Devonian sandstone: Erere, Brazil. 

1874. StreJ>lorhynckus pandora. Nicholson, Paleontology of Ontario, p. 70. 

Corniferous limestone: Port Colborne and Hagersville, Ontario. 

1877. 1Iemip1·onites chem.~mgensis var. arctostriata. Meek, 2 . U. S. Geol. Expl. 40th Par., vol. 4, p. 35, pl. 3, fig. 2. 

Devonian dark limestone: The Gate, northwest of Eureka, Nev. 

1877. Stre]>torhynclms rn:rtas [not McCoy].· Oehlert, Soc. geol. France Bull., 3d ser., vo1. 5, p. 598. 

I. .. ower Devonian: La Baconniere, Mayemi.e, France. 

1877. St1·eptorhynckus de'Vonicus. Oehlert, idem, p. 598. 

Lower Devonian: La Baconniere, St. Jean and St. Germain, Mayenne; in the Sarthe; and generally throughout western France. 

1877. Stre1)torhynchus ~trnbracul~trn [not Schlotheim]. Oehlert, idem, p. 599. 

Lower Devonian: :Mayenne, France. 

1878. Stre7Jlorhynch~ts ~trnbracul~t?n [not Schlotheim]. Kayser, Geol. Specia:Ikarte Preuss. Abh., vol. 2, pt. 4, p. 197, 

pl. 29, .figs. 1, 2. 

Hercynian limestone and accompanying sandy shales: ],{losterhalz, in the Harz Mountains, Germany. 

1878. St7·eptorhynclms ayassizi. Rathbun [not Hartt?], Boston Soc. Nat. Hist. Proc., vol. 20, p. 24. 

Devoniitn [:Eo-Devonia.n] sa.ndstone: Rio Maecuru 3 and ?Rio Curua, Brazil. 

(??l\feso-Devonian]: Erere, Brazil. 

1.882. Stre]Jlorhynchus mnbra~tlurn [not Schlotheim] .. Barrois, Soc. geol. Nord Mem., vol. 2, P·. 239 (pars) (not pl. 9, 

fig. 2). 

A.rnao (Cultrijugatus] limestone: San Roman, Asturias, Spain. 

Ferrofies limestone: Moniello and Itaneces, Asturias, Spain. 

Nieva [Sp·irijer hystericus] limestone: St. Jean de Nieva and Areas, Asturias, Spain. 

1882. Stre]Jlotltynch~tS nmbraculum.. Follmann, Naturh. Ver. preuss. RheinHinde Verh., vol. 39; pp. 147, 148, 178. 

Gntywacke (with Chondrites, Spirijer cultrijugatus, Chonetes plebeia, and C. dilatata): North of Bausendorf on the 

road to Hontheim; mountain Hide between the Schaufelsbach and Elterbach, right side of the Alf Valley 

(p. l.48), and in the overlying shales in the Alf Valley (p. 154); all in the Eifel, Germany. 

Upper graywacke and Chondrites layers: Olkenbach, Germany. 

Lower (bmch.iopod) shales: Olkenbach and nea.r Coblenz, Germany. 

I Hartt states (p. 249): "Cardinal process small, thin, bifid above, with the two small processes on each side projecting backward. A small 

projection In tho center below extends a little forward and toward the ventral valve." This "small projection" may represent the median stump 

of tho cardinal process noted by Hall and by Davidson in the Middle Devonian types, or Hartt may refer merely to the median septum, which 

Is weakly developed. An examination or Hartt's material has been made in the Cornell University Museum collections, but in the short time 

which could bo do voted to tho matter, no specimens could bo found sufficiently well preserved to note tho requisite details of the cardinal process. 

According to Hartt, tho delthyrium has tho width equal to or slightly greater than the height. In tho Lower Devonian type the delthyrium 

fs commonly wider. but thoro is very little difference in regard to this point. · 

2 Meek's spechnens arc regarded by Walcott (1884) as being more conformable with 0. pandora than 0. arctostriata. 

a M'aecuru forms have brachial valve more convex, pedicle umbo more elevated; dental plates reach forward farther, and cardinal process is 

broader thon In Erero forms. Abundant ot Rio Maecuru, rare on Rio Curua. 
36 FAUNA OF THE CHAPMAN SANDSTONE OF MAINE. 

1882. Strophodonta woolworthana. ·Stevenson, Pennsylvania Second Geol. Survey Rept. T2, p. 134. 

Lower Helderberg chert beds just below the Oriskany; Long Ridge, near Beaver Dam Run, King Township, 

Bedford County, Pa. 

1883. Streptorhynchus woolworthana. Hall, New York State Geologist Second Ann. Rept., pl. 39, figs. 25-31. 

Lower Helderberg group: ~ear Ciarksville, N.Y. 

?1884. Streptorhynchus chemungensis· (pars). Walcott, U. S. Geol. Survey Mon. 8, pl. 13, fig. 7 [not fig. 16]. 

Devonian limestone: Eureka district, Nev.; Lone Mountain, 18 miles northwest of Eureka; also on north end of 

Pinon Range, Nev. 

1885. Streptorhynchus umbraculum [not Schlotheim]. Gosselet, Soc. geol. Nord Annales, vol. 13, p. 358. 

Upper Taunusian: In vicinity of Jusseret, Luxembourg. 

1886. Streptorhynchus woolworthanus. Darton, Ani. Jour. Sci., 3d ser., vol. 31, pp. 212-214. 

Lower Helderberg: Cornwall station, Orange County; N.Y. 

1887. Streptorhynchus umbraculum [not Schlotheim]. Schulz, Naturh. Ver. preuss. RheinHinde Verh., vol. 44, pp. 

143, 144; 145. 

Uppermost Coblenzian shales [underlying the Meso-Devonian Orthoceras shales]: Near Olpe, Meggen, Altenkunden, Langenei, Saalhausen, and Wingeshausen, Germany. 

1888. Streptorhynchus umbraculum [not Schlotheim]. Stuart-Menteath, Soc. geol. France Bull., 3d ser., vol. 16, p. 411. 

[Upper Eo-Devonian limestone]: South of Sumbilla and at Eyharce, in the western Pyrenees. · 

1889. Streptorhynchus pandora. Miller, North American geology and paleontology, p. 379. 

Schoharie grit and Corniferous limestone. 

1889. Streptorhynchus woolworthanum. 1\filler, idem, p. 379. 

Lower Helderberg group. 

1889. Streptorhynch1.ts umbraculum [not Schlotheim]. Kayser, K. k. preuss. geol.· Landesanstalt Abh., Neu~ Folge; 

Heft 1, p. 100 (?pl. 12, fig. 4), pl. 18, figs. 1-5. 

Upper Coblenzian (most abundant): Coblenz quartzite; Lower Coblenzian; Taunus quartzite (doubtful); Rhine. 

Valley. 1 

Lower Devonian quartzite sandstone: Kahleberg, in the Upper Harz Mountains, Germany. 

1889. Strophomena woolworthana (identified by James Hall): Pennsylvania Second Geol. SurveyRept. 03; pp. 207, 212. 

Lower Helderberg·Iimestone [New Scotland]: North slope of the Hogback below the mouth of Big Bushkill 

Creek, Pike County, Pa: (p. 207). 

Hamilton.strata: Marshalls Creek, Monroe 'county, Pa. (p. 212). 

1889. Streptorhynchus pQ,ndora. Schuchert, New York State Geologist Eighth Ann. Rept. (for 1888), p. 52. 

Oriskany: North Cayuga, Canada West. 

1891. Streptorhynchus umbraculum [not Schlotheim]. Follmann, Naturh. Ver. preuss. RheinHinde Verh., vol. 45. 

1\fiddle Coblenzian (Coblenz quartzite): Ehrenbreitenstein (p. 131), Oberlahnstein (p. 149). 

Upper Coblenzian (lower part or Chondrites beds): Oberlahnstein (p. 150). 

Upper Coblenzian (upper beds. with S. cultrijugatus): Many localities about the Coblenz district (pp. 134, 135, 

136, 145, 147, 152, 153) and in the Eifel (p. 158). 

1892. Orthothetes woolworthana. Hall and Clarke, Paleontology of New York, vol. 8, pt. 1, p. 255, pl. 9, figs. 25-31. 

Lower Heider berg group: Near Clat:ksville, N. Y. 

1892. Orthothetes sp. a. Ulrich, Neues Jahrb., Beilage Band 8, p. 76, pl. 4, fig. 30. 

Huamampampa sandstone (lower beds): Heights between Huamampampa and Ida, Bolivia. 

1892. Orthothetes sp. {3. ·Ulrich, idem, p. 76. 

Huamampampa sandstone (lower beds): Between Tortora and Chalhuani, Bolivia. 

1895. Streptorhynchus umbraculum [not Schlotheim]. Kayser, Soc. geol. Belgique Mem., vol. 22, p. 209, pl. 4, fig. 13. 

Upper Rhenan: Pepinster, Belgium. 

1896. Orthothe_tes hipponyx. Oehlert, Soc. geol. France Bull., 3d ser., vol. 24, p. 856, pl. 27, :figs. 12-16 (not 9-11). 

Lower Devonian: Santa Lucia, Spain. 

1897. Orthis (?) sulivanti. Schuchert, U. S. Geol. Survey Bull. 87, p. 293. 

Lower Devonian: Faikland Islands. 

1897. Orthothetes chemungensis var. pandora. Weller, Jour. Geology, vol. 5, No.6, p. 629. 

Corniferous limestone: Devil's Bake Oven, near Grand Tower, Jackson County, Ill. (zones 11, 13). 

1898. Streptorhynchus umbraculum. Poussin, Soc. geol. Belgique Mem., vol. 25, p. 32. 

Uppermost Eo-Devonian: Eseneux, Belgium. 

1898. Orthothetes chemungensis [not Conrad]. Bownocker, Denison Univ. Sci. Lab. Bull., vol. 11, pl. 7. 

Coririferous limestones: Harrisburg, Columbus, Marble Cliff, Marion, Kelleys Island,·and Radnor, Ohio. 

1898. Orthothetes umbraculum [not Schlotheim]. Kayser, PaHiont. Inst. Univ. Wien 1\fitt., Bd. 12, Heft 1, p. 38. 

Lower Devonian calcareous beds: Between Pendik and Kartal, north shore of Marmora Sea, Asia Minor. 

Lower Devonian (upper beds): Rhine district, Germany. 

1 The figured specimens shown in pl. 18 are from the Upper Coblenzian (Bausendorf near Wittlich, figs. 1, 4; Miellen below Ems, fig. 2) and 

from the Lower Coblenzian (Stadtfeld, fig. 3; Zenschied, in the Eifel, fig. 5). 

116' 

< 

/' 
,. 

MOLL USCOIDEA • 37 

.l8fJ9. Orthothetos cf. 0. woolworthana. Prosser, New York State Geologist Seventeenth Ann. Rept; (for 1897), pp. 

341, 351. 

New Scotland sha.ly llmestone: Oniskothau Creek (p. 351). 

BecrnJt limestone: Countryman Hill (p. 341) and Oniskethau Creek, Albany County, N. Y. 1 

1899. Orthotlietes pandora. . Prosser, idem, p. 352. 

Scholmrie grit: On.iskethau Creek, Albany County, N.Y. 

189H. Orthotlwtes 'l.vool'worthanus. Schuchert, Am. Jour. Sci., 4th ser., vol. 7, p. 432. 

Ot·.iskn.ny chert: Camden, Benton County, Tenn. 

1900. Orthothetes clwntungensis arctistriatus [not Hall]. Kindle, Indiana Dept. Geology u.nd Nat. Res., Twenty-fifth 

Ann. Hept., p. 593, pl. 6, fig. 3 . 

. Jeffersonville limestone: l!'a.lls of the Ohio, Lancaster, Scipio, Kent, and Ne~vbern, Ind. 

1900. Orthotlwtes woolworthanus. Schuchert, Geol. Soc. America Bull., vol. 11, pp. 283, 293, 307, 322. 

J.Jower Helderbet·g (New Scotland): New York and Tennessee. 

Oriskany·: Becraft Mountain, N. Y., and Camden, Benton County, Tenn. 

1900. Orllwthetes pandora. Schuchert, idem, pp. 293, 325. · 

Upper Oriskn.ny: Oneida and North Cayuga. townships, Ontario. 

1901. Ortlwtlwtes woolworthanus. Prosser, New York State Geologist Eighteenth Ann. Rept. (for 1898), pp. 55, 58 .. 

New Scotln.nd sha.ly limestone: Indian Ladder section, Countryman Hill (p. 55), and High Point, Altamont 

(p. 58); Albany County, N.Y. · 

1903. Orthotlwtes agassizi. Katzer, Geologie des unteren Amazonasgebietes, pl. 11, fig. 6. 

Lower Devonia.n: Hio Curua. a.nd Hio Maecuru, Para., Brazil. 

Middle (?) Devonian: Erere, Parn., B~azil. 

1903. Orthothetes wool'l.vortltanus. Weller, P~1.leontology of New Jersey, vol. 3. 

Coeymans limestone: Just below l!'latbrookville (pp. 85, 278, pl. 27, fig. 5). 

New Scotland cherty limestone: One-half mile below Hainesville (pp. 88, 303, pl. 34, figs. 4. 5). 

1903. Orthothetes pandora. Weller, idem. 

Onondaga limestone: 4 miles, and 2 miles northeast of Flatbrookv.i.lle (pp. 104, 367): 

Newfoundland grit: West of Greenwood Lake (pp. 105, 373, pl. 52, fig. 8). (Not p. 380, pl. 53, fig. 6, which is 

probably 0. arctostriatm.) 

1903. Orthotlwtes woolworthanm. Grabau, New York State Mus. Bull. 69, p. 1059. 

Now Seothmd shales: Becraft Mountain, Columbia, County, N.Y. 

1908. Orthothetes woolworthanus. Van Ingen and Clark, idem, pp. i188, 1190, 1191, 1197, 1203, 1206. 

Basal Coeymans lower, middle, and upper New Scotland, and lowermost Port Ewen: About Rondout, N.Y. 

Oriskany: Glenerie, N.Y. 

1903. Orthothetes sulivani (Morris and Sharpe). Reed, South African Mus. Annals, vol. 4, pt. 3, p. 170, pl. 20, fig. 8. 

Bokkeveld sandstone: Nitkonst and Gydo Pass, Ceres; and Wolvaart's farm, near Ceres Village; Cape Colony. 

1905. Ortho.thetes 1voolworthanu,s mut. gaspensis. Clarke, New York State Mus. Bull. 80, pt. 145. 

Grand Grove limestones: North Shore of Gaspe Bay, Quebec. 

1905. Orthothetes woolworthanus. Shimer, idem, p. 242, 265. 

Upper New Scotland (pp. 195, 200, 208, 220); Becraft (p. 233); Port Ewen (p. 197); Lower Oriskany or 

Dalmanites dentatus ~one (p. 185); Upper Oriskany or Spirijer murchisoni zone (p. 189): Tribolite 

Motmtain, N. Y. · 

1905. Orthothetes 1voolwort'hanus, Williams and Kindle, U. S. Geol. Survey Bull. 244, pp. 28, 40, 47. 

"Oriskany" [Lower Helderberg] coarse sandstone: East Fork of Powell River, Wise County, Va. 

"Oriskany" [Lower Helderberg] sandy and cherty beds: Southern Railway northeast of Big Stone Gap, 'Vise 

County, Va.. 

J.,owistown limestone [upper Lmver Helderberg]: Half a mile north of Covington, Alleghany County, Va. 

1907. Orthothetes (Schuchertella) wool'l.vorlhanus gaspensis. Clarke, New York State Mus: Bull. 1b7, p. 279, figs. 

Lower Devonic:. Grand Greve and Shiphead, Quebec. 

A typical brachial valve of this species was fo~nd at Big Brassua Lake, Somerset County, 

Maine, in the Moose River sandstone. The specimen has the following. characters: 

Shell regular, not distorted; length 32 millimeters, width 38 millimeters; greatest width 

just in front of ~he hinge line; sides of shell nearly straight; front semicircular; greatest convexity of the brachial valve in front, depressed convex toward the umbone; mesial sinus very 

obscure or absent. On the interior of the brachial valve the vascular markings are represented 

by radiating undulose wrinkles. The'musculature is :flabellate, extending about one-third the 

length or a trifle more. It is a little wider than long and is marke~ by a low round median 

septmn or ridge. Posteriorly the n1usculature is bounded by a vertical partition composed 

of the crural bases bearing the lobed cardinal process at the apex. The radial ornan1entation 

1 M:r. Breger has collo:::ted this species in Prosser's Countryman Hill section in the New Scotland limestone. 
38 FAUNA OF THE CHAPMAN SANDSTONE OP MAINE. 

is preserved on the internal mold in the typical Schuchertella fashion, forming a fringe or 

border of close-set regular lines around the margin of the shell from one cardinal angle to the 

other. These lines on the internal mold are rounded, strongly elevated, wider than the interspaces, and as numerous on the sides of the shell just in front of the hinge as they are on. the 

front of the shell. When the specimen was entire there must have been from 155. to 160 lines 

on the margin, or 22 in 10 millimete~s. The lines are equal except for an occasional newly 

. implanted line which, though finer at first, quickly grows to the strength of the others. The 

·lines increase by implantation. · 

.U. S. National Museum, catalogue No. 59700. 

Remarks on Schuchertella woolworthana.-This species was described from the New Scotland 

("Delthyris shaly") limestone of the I-Ielderberg Mountains and Schoharie, Carlisle, Hudson, 

and Catskill, N. Y., and is comnwnly presumed to be a New Scotland species. It occurs 

alao in corresponding bed_s in Tennessee. As is indicated in the synonymy, this species is how 

seen to have the following range: 

Coeymans limestone: Becraft Mountain and Litchfield, N. Y., and northern New Jersey. 

New Scotland limestone: New York, New Jersey, and Pennsylvania, and in supposedly corresponding beds in Tennessee. 

Becraft limestone: Trilobite Mountain, near Port Jervis, N. Y. 

Port Ewen limestone: Becraft Mountain, New York; and in supposedly corresponding horizons in Virginia and at 

Gaspe Bay, Quebec. 

Oriskany sandstone: Glenerie, N.Y.; and in beds containing Oriskany fossils at Camden, Tenn. 

Hamilton formation (Meso-Devonian): Pennsylvania (identified by James Hall). 

Specific relations.-Schuchertella 1.voolworthana belongs to the group of Schuchertella with 

medium to large sized shells, not deformed, marked by a large number of closely set, equal 

or subequal, generally noncrenulated radiating lines. The occurrence of fine lines alternating 

with coarse ones occurs only in exceptional specimens, and the lines are in nearly all specimens' 

close together, not distant or "pectinate." The delthyrium is wider than high. This group 

includes S. sub planus Conrad, S. pandora Billings, S. agassizi Rathbun, S. sulivani Morris 

and Sharpe, and S. umbraculum von Schlotheim (pars). 

InS. subpla,nus the valves are subequal and slightly convex, the cardinal area of the pedicle 

valve is slightly larger than that of the brachial valve, and the radial lines increase by bifurcation and number scarcely 100 on the margin of the shell. In S. woolworthana the valves are 

unequal; the pedicle valve commonly becon1es concave in front; the cardinal area in the 

pedicle valve is much higher than that of the dorsal valve; the radial lines increase rapidly 

by implantation, and commonly number as many as 150 on the margin, though speciruens 

with only 100 lines have been observed. The number of lines is son1ewhat less in S. agassizi 

Rathbun, fron1 Erere, Brazil. Schuchertella woolworthana, from the Helderberg and Oriskany 

of northeast America; S. pandora, of the Schoharie grit and the Hamilton formation; S. S'l.tlivani, 

from the Lower Devonian of the Falkland Islands and South Africa; and S. u~braculum 

Sehlotheim and authors (pars), are four "species" which it is difficult to separate. No distinction can be pointed out between S. woolworthana and S. pandora Billings as regards outline, 

curvature, surface markings, internal musculature markings, delthyrium, and c~rdinal process. 

Schuchertella bainii and S. sulivani, from the Lower Devonian of South Africa and the 

Falkland Islands, agree very well 'with S. pandora and S. woolworthana in visible described 

characters. The South African species have only 110 to 130 radial surface lines on the n1argin,t 

but in the original description of the. species from the Falkland Islands, Morris and Sharpe 

note as many as 150 lines, whieh corresponds with the number observed in some of the North 

American forms of S. woolworthana. It must not be understood that 150 lines on the margin 

is a persistent feature inS. woolworthana. Specimens with this large number are very common, 

as are also individuals with 100 or less; the commonest number is perhaps about 130. In 

S. bainii the lines increase by intercalation and also by bifureation; inS. sulivani, as identified 

in South An1erica, apparently only by bifurcation. 

1 Reed, F. R. C., South African Mus. Annals, vol. 4, pt. 3, p. 170, 1904. 

...: 

'·( 
MOLL USCOIDEA. 39 

Schuchertella woolworthana is more nearly related to many of the shells called by European 

authors S. umbraculum than is any other Alnerican species, not excepting S. chemungensis 

Conrad, which typically has a narrow delthyrium. 1 Indeed, some specimens of S. woolworthana 

fr01n the Coeymans limestone, Litchfield, N. Y., are almost indistinguishable superficially 

fr01n specin1ens of S. umbraculum fr01n the Eifel. Were the labels lost, it would be difficult 

to distinguish the specin1ens. 

One of the most in1portant and constant features in the Middle Devonian Schuchertella 

umbraculum Schlothein1 is the presence, in nearly all fairly well preserved specin1ens from the 

type locality, Gerolstein, and elsewhere in the Eifel, of granulations on the tops of the radiate 

lines. These granulations are conspicuous, according to many authors, particularly Schnur/ 

who described the surface as ''rough, like a file." 

In the Lower Devonian, Schuchertellaa with granulose radial sculpture are unknown. 

European authors have c01umonly c01nbined these Lower Devonian Schuchertellas with S. 

umbraculum, but Oehlert has proposed (1897) to confine Schlotheim's name to the species 

fro1n the Middle Devonian and to separate the Lower Devonian type under the name S. hipZJOnyx Schnur~ Practically the only distinction between the Lower Devonian S. hipponyx and 

the Middle Devonian S. umbraculum, apart from the cardinal process ~tructure to be noted 

below, is the absence of the granulose character of the surface lines in the former and, commonly, their prominence in the latter, though occasionally .Middle Devonian specimens of S. 

umbraculum fail to show any granulations. The Lower Devonian Orthothetes pandora Billings, 

as it occurs in the ''Corniferous" of Canada, has no granulations, but ~all, perhaps erroneously, 

identified with it some granulate New York specimens. 

If this distinction as t.o granulatio11: of surface lines is to be accepted as of specific value, 

S. woolworthana, S. pandora Billings, S. agassizi Rathbun, and S. bainii and S, sulivani Morris 

and Sharpe will be included with the S. hipponyx Schnur as constituting a single specific group, 

to which the name Schuchertella sulivani Morris and Sharpe may be given. In ·America this 

Lower Devonian type, as represented by S. pandora, S. woolworthana, and S. agassizi, appears 

to run up into the Middle Devonian. The S. umbraculum type in America is represented · 

apparently only by the specimens (erroneously~) recorded by Hall 3 as S. pandora Billings. 

IIall's specin1ens conforn1 with Schlotheim's S. umbraculum not only in showing granulated 

surface lines but also in having a small stump between the two branches of the cardinal process. 

'rhis stump appears in S. umbraculum, as it occurs in England and as it has been figured by 

Davidson. In the Canadian specin1ens of S. pandora not only are the surface lines persistently 

not crenuhttecl, as both Billings and Nicholson observed, but Billings has called attention to 

the fact that the two divisions of the cardinal process do not haye any median stump or proc.ess 

between then1. It has been shown by Hall 3 and by flail and Clarke 4 that S. woolworthana 

agrees with S. zmndora Billings (not S. zJandora Hall) in lacking the tnedian stump between the 

two divisions of the cardinal process. Thus in the granular-lined S. umbraculum there appears 

to be a median process between the two processes of the cardinal apophysis, but this median 

stump is absent in the smoothly lined S. pandora Billings and S. woolworthana Hall. These 

two distinctions taken together may prove of some importance in disentangling the synonymy 

of S. hiz)JJonyx Schnur (=8. sulivani Morris and· Sharpe), and S. umbraculum Schlotheim s. str. 

• In tho specimens of S. chcmungensis with fine radial surface lines and in Upper Devonian and Carboniferous forms in general which might 

otherwise be regarded as similar to S. woolworthana the delthyrium is much narrower than in the latter species. (Cf. Paleontology of New York. 

vol. 4, pl. 10, figs. 11, 12,,14, 16, and 23, 1867.) In tho Lower and M'iddlo Devonian species S. woolworthana, S. pandora Billings, S. agassizi Rathbun, S. suli11ani and bctinii M:orris and Sharpe, S. hipponyx Schnur, and S. umbraculum Schlotheim, the delthyrium is wide, twice as broad as 

high, whereas in the Upper Devonian typical S. chemungcnsis Conrad as well as in tho MississippianS. desiderata Hall and Clarke the delthyrium 

Is much narrower. In tho typical Carboniferous forms of Schuchcrtella crenistria Phillips tho delthyrium is also narrow, as has been emphasized 

by Do Vornoull (Soc. g6ol. Fmnco Bull., 2d sor., vol. 7, p. 161, footnote). 

2 Pnlaeontogmphiea, vol. 3~ p. 216, 1853. 

s :J~aloontology of Now York, vol. 4, p. GO, 1867. 

c :Paleontology of Now York, vol. 8, pt. 1, 1892. 
40 FAUNA OF THE CHAPMAN SANDSTONE OF MAINE. 

ScnucHERTELLA DEFORMIS I-Iall. 

Plate VII, figmes 6a and 6b. 

1857. Orthis dejormis. Hall, New York State Cab. Nat. Hist. Tenth Ann. Rept., p. 44. 

Helderberg Mountains, New York [no more precise locality or formation mentioned]. 

1859. Orthis dejormis. Hall, Paleontology of New York, vol. 3, p. 174, pl. lOA, fig. 13, pl. 15, fig. 3. 

Lower Helderberg shaly limestone [Naw Scotland]: Helderberg Mountains, N.Y. 

1883. Streptorhynchus deformis. Hall, New York State Geologist Seconc\ Ann. Rept., pl. 39, fig. 32. 

Lower Helderberg group: Borst's mill, Schoharie County, N.Y. . 

1892. Orthothetes dejormis. Hall and Clarke, Paleontology of New York, vol. 8, pt. 1, p. 255, pl. 9, fig. 32. ' 

!,ower Helderberg group: Borst's mill, Schoharie County, N.Y. 

1897. Orthothetes deformis. Schuchert, U.S. Geol. Survey Bull. 87, p. 296. 

Lower Helderberg: Albany County, N.Y.; Cumberland, Md. 

1900. Orthothetes deformis. Schuchert, Geol. Soc. America Bull., vol. 11, pp. 264, 283. 

Lower Helderberg (New Scotland): New York and Maryland-Virginia area. 

1903. Orthothetes deformis. Schuchert, U. S. Nat. Mus. Proc., vol. 26, p. 418. 

Manlius limestone: Devils Backbone, near Cumberland. Mel. 

This characteristic form is represented by a pedicle and a brachial valve. The pedicle 

valve has a length of 15 millimeters; the hinge line is straight, about 17 ·millimeters long; 

cardinal extremities pointed, not extended; sides slightly cmiverging toward hinge; maximum 

width in middle, 19.75 millimeters; front of shell broadly elliptical. Pedicle valve convex 

throughout; umbonal portion ventricose, swollen, somewhat distorted; shell becoming depressed. 

in front by an indefinable undulation; maximum depth one-fourth the length. Cardinal area 

rather high (3.5 millimeters), perpendicular to the swollen umbonal portion of the shell; area 

finely striate vertically; delthyriu1n acute-angled (nearly 60°). R·adial surface lines rounded, 

numerous, increasmg by intercalation very freely in front; interspa~es slightly wider than the 

lines in some parts, whereas in other parts the lines are narrower than the intervening furrows. 

About 75lines have been counted on the margin of this small specimen, or 10 to 12 in the space 

of 5 millimeters. 

The brachial valve is somewhat distorted, ventricose, subcircular in outline; length, 23.5 

millimeters; greawst width, 27.5 millimeters in the middle; cardinal extremities broadly rounded; 

hinge short; umbonal portion strongly convex; maximum depth, 9.75 millimeters at about the 

middle of shell; median septum low, rounded, less than half the· length of the shell. Radial 

surface lines rounded, closely set, equal, increasing by implantation, curving hardly perceptibly· 

on the sides.1 The specimen when complete must have had about 110 surface lines on the margin. In a very well preserved part of the shell the surface of each radial s;urface line is covered 

with two to four extremely fine, threadlike strire.2 No concentric growth lines are present. 

This species can be readily recognized, for it is twisted or deformed and has a much swollen 

umbone in the pedicle valve. In front of this swollen umbone the pedicle valve is depressedconvex, flat, or concave, and is wrinkled concentrically. The cardinal area of the pedicle valve 

is high, delthyrium acute, less than 60°; cardinal area in the brachial valve linear or absent. 

The brachial valve is ventricose behind and very strongly convex throughout, much more so 

than the pedicle valve. The cardinal extremities are rounded. Radial surface lines are fine, 

close set, and equal in si~e, increasing by intercalation. 

The Maine material corresponds very, closely with the New York specimens. The specimens described are presumably young. The depression' in front by an indefinable undulation is 

evidently the beginning of the depression which in older shells characterizes the greater part of 

the surface in the anterior portion. 

Locality: Chapman sandstone, west side of Edmunds Hill, Chapman Township, Aroostook 

County, Maine. 

U.S. National Museum, catalogue No. 59701. 

1 This character is one of the principal criteria to distinguish this specimen from superficially similar, small, circular valves of Hipparionyx 

occurring in the same locality. 'In Ripparionyx the surface lines curve very strongly on the sides, and near the hinge are directed upward. 

II This character also appears in well-preserved parts of the shell in typical specimens ofS. dF/ormis from the lower part of the Helderberg group 

(Coeymans limestonll), of Litchfield, N.Y. · 

I~ 
MOLL USCOIDEA. 41. 

00'InJXt1'isons.-In spite of its deformation, S. dejo1''1nis presents some. characters which are 

pretty constant in appearance and which will serve to distinguish it easily from the other 

A1nerican fonns. S. deform is is the first deformed Schuchertella recorded in North Amedcan 

faunas, with the probable exception of a very similar and yet peculiar Schuchertella 0) 'from 

the Decker limestone in New Jersey. This form, called by Weller 1 S. deckerensis, resembles 

S. deformis in convexity and ornamentation, but whereas in S. deformis the umbo is the most 

cmnrex or gibbous portion of the pediCle valve, inS. deckerensi.s Weller this part of the shell is 

deeply concave and is n1erely a large cicatrix .of attachment. In Europe similar deformed 

Schuchertellas, widely distributed in the Lower Devonian and occurring also in the Middle and 

Upper Devonian, are grouped under the nameS. devonicus, but this name, as indicated by the 

following synonymy, evidently covers several species. · 

1849. Orthiscrenistriavar. devon1:ca. Keyserling, Geogn. Beobachtungei1, p. 221, pl. 7, fig. 7. 

1849. Leptmna devonica. D'Orbigny, Prodrome, vol. 1, p. 90. 

1850, 1855. Orth?:s devonica. Soc. geol. France Bull., new ser., vol. 7, p. 161; vol. 12, p. 1016. 

1865. Streptorhynch'l.tS devonicus. Davidson, British fossil Brachiopoda (Devonjan), p. 80 .. 

1869. Orthis devonica. De Verneuil, in Tschihatscheff, Asie Mineure, Paleontologie, p. 34. 

:t87fL StrejJtorhynchus devonicus. Kayser, Die fauna der altesten Devon-Ablagerungen des Harzes, p. 199, pl. 29, 

figs. 3-4, 1878. 

A deformed Schuchertella from the Konieprussan beds (etage F) of Konieprus, Bohen1ia, 

was described in 1847 as Orthis distorta Barrande. 2 These beds are now regarded as of the age 

of the Alnerican }Ielderberg to Onond.aga (" Corniferous "). 3 The species occurs also in the 

Thuringian Tentaculite beds:' This species is regarded by Kayser 5 as identical with S. deformis 

IIall, and the strong similarity between the two is also noted by Schuchert 6 and may be atfirmed 

here. In the American species, however, the brachial valve is much more gibbous than the 

pedicle valve, which is son~etimes flat or even concave. In the Bohemian species the two valves 

are subequally and gently convex/ and the brachial valve is apparently never gibbous as in S. 

diformis I-Iall. 

Genus mPPARIONYX (Vanuxem, 1842) Hall and Clarke, 1892. 

HrPPARIONYX UNGUIFORMIS Conrad. 

Plate VII, figures 1-5, 7, 8. 

1838. Leptmna unguijormis. Conrad, New York Geol. Survey Second Ann. Rept., p. 112 (name only). 

"Second group": New York. 

1840. Strophomena unguijormis. Conrad, New York Geol. Survey Fourth Ann. Rept., p. 203 (name only). 

Oriskany sandstone: Schoharie, N.Y. 

1841. Atrypa unguijormis. Conrad, New York Geol. Survey Fifth Ann. Rept., p. 36 (name only). 

Middle series, .including the Oriskany: New York. 

1842. Hip]>arionyx proximus. Vanuxem, Geology of New York, Rept. Third Dist., p. 124, fig. 29, No. 4. 

Oriskany sandstone: [Third geological district, central New York.] 

1843. Atrypa unguijormis. Conrad (Hipparionyx .Proximus Vanuxem), Hall, Geology of New York, Rept. Fourth 

Dist., p . .149, fig. 4. 

Oriskany sandstone: New York. 

1843. Orthis conradi. 8 Castelnau, Essai sur le systeme silurien de 1' AmeriquB septentrionale, p. 37, pl. 15, fig. 4. 

Schoharie. N. Y. 

1843. Orthis t1..nguijo~is. Castelnau, idem, p. 37, pl. 15, fig. 3. 

Schoharie, N.Y. 

cf. 1853. Orthis hipparionyx. Schnur, Palaeontographica, vol. 3, p. 217, pl. 40, fig. 1. 

Gray:wacke beds: Priim, in the Eifel, Germany. 

• Paloontology.of New Jersey, Paleozoic faunas, p. 229, pl. 20, figs. 6 and 7. 

1 Barrrutdo, Joachim, in Hl\ldlnger, Wilhelm, Naturwissenschaftlicbe Abbandlungon, vol. 2, p. 20.'i, pl. 19, fig. 2, 1847-48. 

a Schuchart, Charles, Geol. Soc. America Bull., vol. 11, p. 264, 1900. 

• 1Uchter, Deutsch. geol. Gesell. Zoitschr., vol. 18, p. 416, pl. 6, fi,:s. 8-10. 

~ Kl\yser, Emanuel, Die :Fauna der illtcsten Devon-Ablagerungen des Harzes, p. 199, 1878. 

o Op. cit., p. 26•1. 

T Barmnde, Jol\chim, Syst~mo silurimt du centre de Ia Boh~me, vol. .'i, pl. 58, figs. 4-5; pl. fiO, fig. 4, 1852. 

s 'l'his species is described on p. R7 before 0. 1£nguiformi...~, but from the description it is evident that the latter was a well-known fossil. 

Cnstolnau sl\ys of 0. conradi: ''Cettc espece l\ assez Ia forme de l'unguiformis; comme elle, elle est orbiculaire," etc. 
.42 FA UN A OF THE CHAPMAN SANDSTONF: OF MAINE. 

1858. Atrypa unguiform~s. Rogers, Geology of Pennsylvania, vol. 2, pt. 2, p. 826, fig. 631. 

Meridian formation: Pennsylvania. 

· 1859. Orthis hipparionyx. Hall, Paleontology of New York, vol. 3, p. 407, pl. 89, figs. 1-4; pl. 90, figs. 1-7; pl. 91, 

· figs. 4, 5; pl. 94, fig. 4. 

Oriskany sandstone: Albany, Schoharie, Herkimer, Oneida, and Onondaga counties, N.Y. 

1859. Strophodonta intermedia. Hall, idem, p. 482, pl. 95 (A), figs. 13-14. 

Oriskany sandstone: Cumberland, Md. 

1860. Atrypa unguiformis. Dawson, Canadi.an Naturalist, vol. 5, p. 140. 

Oriskany iron ore beds: Nictaux, Nova Scotia. 

1860. Orthis unguiformis. · Emmons, Manual of geology, p. 129, fig. 115, Nos. 4, 5 (also in 2d ed., 1863). 

Oriskany: No locality indicated. 

cf. 1865. Orthis hipparionyx? Davidson, 1 British fossil Brachiopoda (Devonian), vol. 3, p. 90, pl. 17, figs. 8-11. 

Devonian sandstone, Looe, Cornwall. 

1878. Orthis hipparionyx. Ashburner, Pennsylvania Second Geol. Survey Rept. F, p. 239. 

Oriskany (Meridian) ferruginous sandstone: Railway cut at Three Springs and at the ends of Royer and Sandy 

ridges, Huntingdon County, Pa. · 

1881. Orthis hipparionyx (?). Davidson, 2 vol. 4, pt. 4, p. 347, pl. 39, fig. 1. 

Budleigh-Salterton pebble bed. · 

1882. Orthis hipparionyx. I. C. White, Pennsylvania Second Geol. Survey Rept. G6, p. 124. 

Oriskany s"andstone: Brodhead Creek, Monroe County, Pa. 

1883. Streptorhynchus hipparionyx. Hall, New York State Geologist Second Ann. Rept., pl. 39, figs. 33-36: 

Oriskany: New York; Cumberland, Md. 

1887. Orthis hipparionyx. Ami, Canada Geol. Survey Ann. Rept., new ser., vol. 2, p. 9N. 

Oriskany slates and sandstones: Campbell River, at mouth of Don River, New Brunswick. 

1889. Orthis hipparionyx. Claypole, Pennsylvania Second Geol. Survey Rept. 03, p. 130. 

Oriskany sandstone: Various outcrops in Perry County, Pa. 

1889. Orthis hipparionyx. Simpson, idem, p. 209. 

Oriskany sandstone: Royers Ridge, north of road crossing at Orbisonia, Huntingdon County, Pa. 

1889. Strophodonta intermedia. Schuchert, New York State Geologist Eighth Ann. Rept. (for 1888), p. 52. 

Oriskany: Cumberland, Md. 

1889. Orthis hipparionyx. Lesley, Pennsylvania Second Geol. Survey Rept. P4, p. 517, figs. 

Oriskany sandstone: Huntingdon, Perry, and Monroe counties, Pa. (For localities see 1878, Ashburner; 1882, 

I. C. White; 1889, Simpson; 1889, Claypole.) 

1891. Atrypa unguiformis. Dawson, Acadian geology, 4th ed., p. 499. 

Nictaux iron ore and accompanying slates: Nictaux River, Nova Scotia. 

1892·. Hipparionyx proximus. Hall and Clarke, Paleontology of New York, vol. 8, pt. 1, p. 257, pl. 9, figs. 33-36; 

pl. 15A, figs. 9-11. 

Oriskany sandstone: New York; Cumberland, Md.; Cayuga, Ontario. 

1892. Hipparionyx proximus. Clarke, Am. Jour. Sci., 3d ser., vol. 44, p. 413. 

Oriskany: Becraft Mountai.n, N, Y. 

1899. Hipparionyx proximus?. Prosser and Rowe, New York State Geologist Seventeenth Ann. Rept. (for 1897), 

p. 342. 

Oriskany dark quartzitic sandstone: Countryman Hill section, Helderberg Mountains, N. Y.3 

1899. Hipparionyx proximus?. Schuchert, Am. Jour. Sci., 4th ser., vol. 7, p. 431. 

damden chert: Camden, Benton County, Tenn. 

19.00. Hipparionyx proximus. Schuchert, Geol. Soc. America Bull., vol. 9, pp. 314, 315, 321, 325. 

Camden chert: Camden, Benton County, Tenn. (p. 321). 

"Monterey" formation: Cumberland, Md. 

Oriskany: Branch of Potomac River, Pendleton County, W.Va. (p. 315); Oneida and North Cayuga townships, 

Ontario (p. 325): 

1900. Hipparionyx proximus. Clarke, New York State Mus. Mem., vol. 3, No~ 3, pp. 52, 74. 

Oriskany: Becraft Mountain, N.Y. (p. 52); Glenerie, N.Y. (p. 74). 

1901. Hipparionyx proximus. Prosser, New York State Geologist Eighteenth Ann. Rept., p. 59. 

Oriskany dark calcareous sandstone: Altamont section, Helderberg Mountains, N. Y. 

1 The form from Looe, Cornwall, is the species subseqil.ently figured by Davidson under the same name from the Triassic pebble beds of Budleigh Salterton, near Exmouth, Devonshire. The form occurring in these two places is not Hipparionyx unguiformis, the muscular scars in the 

British shells being very much smalle;. 

t The configuration of this shell is unlike Hipparionyx unguiformis and the muscular markings are smaller. It appears quite certain that this 

particular specimen is not Hipparionyx unquiformis, as was pointed out by Hall and Clarke (Paleontology of New York, vol. 8, p. 25i). 

a Mr. Breger has collected material from this outcrop in the roadbed above Mr. Parrish's house, where the Hipparionyx is very rare and, as 

Is noted by Prosser, small. There is not, as he remembers the material, sufficient cause to doubt the identification. 

Though this species is very common and. very large in the arenaceous Oriskany of central New York, where it is one of the characteristic and 

typical fossils of that formation, it is small and rare in the Helderberg Mountains; not recorded from Trilobite Mountain; very rare and small in 

New Jersey; rare and small at Camden, Tenn.; absent at Perce Rock and in the Gaspe beds of Quebec; absent at Rondout, though common and 

typical near by at Glenerie and Becraft Mountain; rare at White Sulphur Springs; and absent in the other Appalachian Oriskany localities 

recorded by Williams and Kindle. · 

"o; 
MOLL USCOIDEA. 43 

1903. Hipparionyx proxintus. Weller, New Jersey Geol. Survey, Paleontology, vol. 3, pp. 101, 346, pl. 45, fig. 12. 

Spirije:r nt'ltrchisoni zone or upper Oriskany (siliceous limestone): Peters Valley, N. J. 

1903. I:lipparionyx JJroxirnus. Van Ingen and Clark, New York State Mus. Bull. 69, pp. 1203, 1206. 

Oriskany sands and cherty limestones: Glenerie, N.Y. 

1905. HiJJparionyx proxirnus. Williams and Kindle, U.S. Geol. Survey Bull. 244, pp. 34, 47. 

Oriskany coarse sandstone: Rear of Alabama Row, White Sulphur Springs Hotel, W.Va. 

1905. Ifipparionyx proxirnus. Harris, Guide to the geology of Union Springs, p. 4, pl. 12, figs. 1-2. 

Oriskany sandstone: Yawger's Woods, Union Springs, N. Y. 

1905. HiJJparionyx proximus. Clarke, New York State Mus. Bull. 80, pp. 145, 148. 

Grande Greve limestones: North shore of Gaspe Bay, Quebec. 

1905. Hipparionyx proxirnus. Clarke, New York State Mus. Bull. 82, p. 41. 

Oriskany granular quartzite: 'l'ully quadrangle, N.Y. 

Oriskany sandstone: Yawger's Woods, near Union Springs, and at Oriskany Falls, N. Y. 

This remarkable species occurs in l\1aine in several modifications, all of which are likewise 

represented by typical material from New York. The seven specimens in the l\1aine collections 

are all pedicle valves and all small; the largest is 35 millimeters long. The outline is commonly · 

subcircular, with length and breadth as 7: 8, widest in the middle. This is the form occurring 

in locality 1099 M, but the speci1nens from Edmunds Hill are more ·elongate and have the 

length equal to the breadth. The pedicle valve is convex for a small space on the umbo, 

depressed on the sides and body of the shell and flat or very slightly concave in front. The 

'hinge line is short, straight, or slightly arcuate; cardinal area ;ery low. The n1usculature is 

flabellate, large, more than half. the length of the shell. It is bounded on the sides by the 

dentallamellre which diverge at an acute angle 1 (Pl. VII, fig. 5), or at a right angle (Pl. VII, 

fig. 2), and continue as low broad ridges which curve inward and approach a rounded mesial 

septum. 'l'he n1edial s.eptum is developed in the forward part of the musculature and extends 

as far back as the adductor cicatri..-x:, which is oval and elevated. There is no n1edian septum 

in the u1nbonal part of the musculature in the pedicle valve. In front of the musculature the 

interior of the shell is raised by a pitted callosity, probably representing the ovarian pits and 

duct. Surface n1arked by fii1e subequal radial lines which curve strongly on the sides and 

appreciably upward (and outward) about the umbo and cardinal extremities. The greatest 

curvature of the lines is near the n1argin of the shell. The lines are round, subequal, strongly 

elevated, and as wide as their interspaces, number 11 or 12-rarely 10 or 13-in the space of 

5 1nillimeters, and increase by i1nplantation. Obscure indications in the Maine and New York 

specimens of finer, fiber-like lines over the surface may be due to 1naceration of the shell. In 

internal nwlcls of pedicle (and brachial) valves the radial lines are commonly represented by a 

narrow fringe 01: border of short lines around the margin of the shell, along the posterior margin 

nearly to the cardinal extren1ities. The lines in this fringe are vertical or nearly so, resembling on a coarser scale the denticulations of stropheodontoids. · 

This nearly vertical 'lining along the posterior margin played no part in hinge articulatio.11, 

as in stropheodonts; the structure described is both functionally and structurally very distinct 

fr01n the denticulations in stropheodonts. 

After the .preceding description was ·written a small brachial valve which can safely be 

referred to this species was found in the collections fron1 Edn1unds Hill. The specimen (an 

external n1old and also an internal1nold) shows strong upward curving of ·the radial lines on 

the posterior 1nargins. The speci1nen is broadly subcircular, 26 millimeters long, 35 millinleters wide (greatest width in the 1niddle), and 7 1nillimeters high; the greatest convexity is 

just back of the middle. The 1narginal fringe of short lines around the edge is present. The 

lines increase by bifurcation, are very strongly elevated, about as wide as the·interspaces, and 

nun1ber 12 or occasionally 13 in 5 1nillimeters at 15 to 20 1nillimeters fr01n the beak. 

Locality: Chapp1an snndstone, Edn1unds Hill, and west side of Edmunds Hill, Chapman 

Township, Aroostook County, l\1aine. 

U.S. Nationall\1useum, catalogue Nos. 59702, 59703 .. 

1 Paleont?logy of New York, vol. 3, pis. 89, 90, 1859. 
44 FAUNA OF THE CHAPMAN SANDSTONE OF MAINEo 

Family PRODUCTID.tE Gray. 

Genus CHONETES Fischer de Waldheim, 1837. 

CHONETES STRIATISSIMUS sp. no.v. 

Plate VIIi, figure 24; Plate IX, figures 1-10, 13, 14, 17, 18; Plate X, figure 17. 

Shell depressed, convexo-concave, finely lineate, and with a n1idrib on the pedicle valve. 

Outline transversely subquadrate approaching the semicircular, width varying from a little 

over 1.5 to 1.8 times the length; greatest width in front of the hinge line just back of the 

middle. }Iinge line straight, very little less than the maximum width of the shell; hinge 

extremities sharp cornered, obtuse; sides of the shell subparallel, slightly diverging, and nearly 

straight for about half the length, then broadly curving into the front margin of the shell, 

which is strongly arcuate. The pedicle valve is .depressed convex and without any definitely 

flattened demarcated ears; the slight convexity is maintained, more or less uniformly, over all 

the surface. A typical average specimen (No. 749, Pl. IX, fig. 2), 18 millimeters wide and 

10 millimeters long, has a height of 1.5 millimeters. The maximum height and gibbosity 

(about one-seventh the length) are on the umbonal portion; the beak does not extend appreci-

. ably over the hinge line. The brachial valve is flat over its greater extent and becomes slightly 

concave in the front in medium-sized shells. Cardinal area linear in the pedicle valve; not 

evident i:rt the brachial valve. 

In the pedicle valve the teeth are strong, thick, short, ·leaving in the internal mold two 

short, shallow, broad excavations which ~re strongly divergent. Between the teeth there is a 

median septum which is very narrow and· short, extending one-fourth the length of the shell 

or less. The muscular and vascular impressions are not observed in any of the specimens .at 

hand. In the brachial valve there is a blunt low ridge or septum extending one-third the 

length of the shell, and on each side of it there diverges a similar but fainter and slightly 

shorter ridge. The crural. processes diverge at an angle of about 180°, being nearly parallel 

to the hinge. 

The grooves between the radial elevated surface lines are deeply pitted, but the pitted 

. structure does not reach the surface and is Iiot discernible on the outside of the shell. On 

the inner laminre of the shell, especially on the internal molds, these rows of pits between the 

elevated lines are very plainly seen. T4ey represen.t, on the inner surface of the shell, little 

elevated punctre or spinules with an inclosed pore, and in passing from the inside surface of 

the shell toward the outside they are inclined backward. These punctre are, as has been st,ated, 

developed in the strire or grooves between the radial lines and are not to be seen on the elevated 

lines nor on the external surface of the shell. 

The surface is covered with rounded to subangular, very fine 1:adiating lines, barely visible 

to the naked eye, about 30 (varying between 28 and 34) in the space of 5 millimeters and in a 

medium-sized adult shell about 200 in number on the· margin. The radially lined surface 

extends up to the hinge border and to the beak. These lines are uniform in size, somewhat 

flexuous, nearly as fine on the margin of an old shell as on the younger portion of the shell, and 

are also strongly impressed on internal molds. The mode of increase is by- both bifurcation and 

implantation, one method or the other being variably predominant on different individuals. In 

the pedicle valve there is found on the surface a median keel or much stronger rib, formed by the 

coalescence of two or sometimes three radial lines and extending to the tip of the beak. This 

median keel is less pronounced on the internal mold, where it is hardly definable except in front; 

and in the brachial valve there is no corresponding feature. 

, Very fine, closely set concentric strire are visible under the lens and are especially prominent 

in front of the hinge line on the sides, particularly in the brachial valve. The remains of three, 

four, or possibly five spines maybe seen on each side of the center along the hinge margin of the 

pedicle valve. These extend outward and backward at an angle with the hinge line of over 60°, 

curving slightly, with the convex side of the curve outwar.d. The distinguishing features of this 

easily recognized species are the fine radial lines (commonly about 30 lines in the space of 5 

millimeters), the median keel, and the depressed convexity. · 

-· 
"1 

MOLL USCOIDEA. 45 

Locality: In the Chapman sandstone, 2 miles west of Presque Isle Stream, very con1mon; 

2t 1niles west of Presque Isle Strean1 (1099 K), common; Edmllnds I-Iill (1.099 C), con1n1on; 

west side of Edmunds I-Iill (1099 M), a varietal modification is common; all in Chapman Town-

' ship, Aroostook Cou~1ty, :Maine. Along the west side of Edmunds Hill the n1ore coarsely lined 

species Chonetes novascoticus I-Iall is the dominant Chonetes; the n1ore- finely lined shells referable 

to Chonetes striatissimus are. comn1on in apparently only a single layer. This layer contains 

Clwnetes striatissimus and S1Jirije1· cyclopterus in abundance; no lan1ellibranchs were observed. 

Chonetes novascoticus occurs in lithologically similar rock. It is possible that Chonetes striatissimus may be an offshoot from the Chonetes novascoticus stock, but the two are not connected 

in the Chapman sandstone fauna by any intennediate forms. 

U.S. National ~1q.seum, catalogue Nos. 59704, 59705, 59706. 

Comparisons.-Among the Chonetes species resembling C. striatissi1nus are the Carboniferous forms C. shumardianus De Koninck 1 and C. papilionacea Phillips. 2 Neither of these 

Carboniferous species has a median rib, nor is their large size ever, approached by C. striatissimus, 

so far as lmown, though they agree in the depressed convexity and fine striation. 

The nearest allies are the similarly fine-lined Chonetes venustus Barrande 3 and C. bohemicus 

Barrande 4 frOill etage F, Bohemia. Chonetes bohernicus is a gibbous shell, lllUCh more so than 

C. striatissimus,· C. rpenustus, though less gibbous than C. bohemiC'I.lS, has an extended hinge with 

acute extremities and well-developed auricles, whereas in C. striatissimus the hinge is never 

extended-in fact, is less than the maximum width-and ears are not develoi>ed. The median 

riblet of C. striatissimus is not at nll developed in C. venustus and rarely if at all in C. bohemicus. 

(See Barrn.nde's pl. 46, fig. 2tt.) 

CHON~TES NOV ASCOTICUS Hall. 5 

Plate IX, figures 11, 12, 15, 16, 19; Plate X, figures 1, 2, 3, 5-16, 18-29, 32, 33. 

1837. "Producti." Jackson,li'irstreporton thegeologyoftheStateofMaine, p.128, p1.1, figs. 5,8. 

Graywacke: Maine. 6 

1860. Chonetes nova-scotica. Hall, in Dawson, J. W., Silurian and Devonian rocks of Nova Scotia, p. 13. 

Upper Arisaig (upper Silurian); Arisaig, Nova Scotia. 

1860. Chonetes Nova-Scotica. Hall, Canadian Natu:r;alist, vol. 5, p.144, fig. 2. 

Upper Arisaig (upper Silurian): Arisaig, East River, Pictou, and Nictaux, Nova Scotia. 

1862. Chonetes nova-scoticus. C. H. Hitchcock, Maine Board Agr. and Geology, Sixth Ann. Rept., p. 238. 

Lower Helderburg_: Pembroke, Maine. 

1878. Chonetes Nova-Scotica. Dawson, Acadian geology, 3d ed., pp. 498, 595, fig. 199 .. 

Upper Arisaig (upper Silurian): Arisaig and East River, Pictou, Nova Scotia. 

Nictaux limestone, upper Silurian, older than the Ferriferous beds: Nictaux, Nova Scotia. 

?:1.879. Chonetes Nova-Scotica. Hall, New York State Mus. 'l'wenty-eighth Ann. Rept., p. 155, pl. 22, figs. 11-14. 

Waldron shales: Waldron, IncU · 

?:1.882. Chonetes Nova-Scotica. .Hall, Indiana Dept. Geology and Nat. Hist. Eleventh Ann. Rept., p. 293, pl. 22, figs. 

11-14. . 

Waldron shales: Waldron, Ind. 

not 1890. Chonetes cf. C. Nova Scotica Clarke, Mus. Nac. Rio Janeiro Arch., vol. 9, p. 24. 

Silurian: Rio Trombetas, Para, Brazil. 

1900. Chonetes nova scotica. Williams, U. S. Geol. Survey Bull. 165, p. 79. 

Chapman sandstone: Chapman Plantation, Aroostook County, Maine (locality 1099). 

1907. Chonete8 aroostookensis. Clarke, New York State Mus. Bull. 107, p. 264, figs. Lower Devonic [Chapman sand-

. stone]: Edmunds Hill, Chapman, Maine. 

I De Koninck, IJ. G., Recherches stir les animaux fossiles; Monographic du genre Chonetes, 1847, p. 192, pl. 20, fig. 1. The species is from the 

Keokuk Umestone (Mississippian) of Kentucky and Indiana. 

2ldem, p. 187, pl. 19, fig. 2. This species occurs in the Lower Carboniferous limestones or England, Irelantl, France, Belgium, Russia, etc. 

3 Barrande, Joachim, Systcme silurien du centre de Ia BoMme, vol. 5, pl. 46, figs. I, 1-6, 1852. 

4 Idem, pl. 46, figs. II. 1-6. 

G Compare C. tenuicostata Oehlert, Soc. geol. France Bull., 3d ser., vol. 5, p. 599, pl. 10, figs. 13-13a, 1877 (Lower Devonian: LaBaconniere and 

St. Germain, Mayenne, France); als~? C.filistriata Walcott, U.S. Geol. Survey Mon. 8, p. 127, pl. 13, fig. 15,1884 (Lower Devonian limestone: Combs 

Peak, Eureka district, Nev.); and Chonetes sarcinulatus Schlotheim and C. latus Von B uch (see text). 8 Jackson~s figures appear to represent a compressed form of the species which is abundant in the gray shales of ~he P.embroke formation of the 

Eastport quadrangle, Maine. The old Hard on Clarke farm near Kelly Point, Pembroke Neck, was probably the source of Jackson's material. 7 Tho largest Waldron specimen has a width of 16 millimeters, but the general size of the material is less, perhaps 10 or 11 or 14 millimeters. All 

tho specimens from Waldron belong, according to Hall, to the form with a strong median ray on the pedicle valve. The Waldron material differs 

from tho Nova Scotian inlthe small size, in the persistence of the median ray or buttress, and in the disposition of the spines and other details, and is 

probably a distinct species. 
46 FAUNA OF THE CHAPM;AN SANDSTONE OF MAINE. 

The shell is of rather large size when mature; small specimens are about 6 by 10 n1illimeters; 

average specimens are about 10 by 15 millimeters, and large individuals attain a width of 30 

millimeters and a length of 14 millimeters. Depressed convexo-concave. Radial surface lines 

fine, but coarser than in C. striatissimus~· midrib developed only occasionally. 

Outline semicircular; width greater than length, varying from 11- to 2 times the length. 

Hinge line straight, commonly equaling the greatest width of the shell, though occasionally a 

little less. Sides nearly perpendicular to the hinge line, curving in front; front margin a broad, 

shallow arch. The pedicle valve is depressed-convex; the convexity is greatest over the posterior central portion and the umbo; a more or less uniform slope is maintained toward the front 

and toward the sides, so that the ears are not definitely demarcated. Occasionally there is an 

obscure sinus in the pedicle valve. Maximum depth of a shell 12.5 millimeters long is somewhat less than 2 millimeters, or approximately one-seventh the length. The brachial valve 

is slightly concave throughout. Cardinal area discernible in both valves; slightly higher in 

the pedicle than in the brachial valve. Shell structure pitted as in Chonetes striatissimus, the 

description under that species being also applicable here. The cardinal process was seen to 

be forked in one of the brachial valves. 

The surface is covered with rounded or subangular, moderately ·fine, radial lines. Usually 

there are 17 to 19 lines in the space of 5 millimeters, the extremes being 15 and 22 in mature 

shells. In young shells there may be 22 to 24lines in 5 millimeters. Mature shells attaining a 

width of 10 'or 11 millimeters or a length of 19 or 20 millimeters have from 110 to 130 lines on 

the margin, generally nearer the former number. A stronger median riblet is occasionally 

present, but more frequently absent;. in the larger specimens it is commonly absent. The 

radial lines are somewhat flexuous, are apparently as evident on the interior as on the exterior 

molds, and cover the entire surface. The mode of increase is both by bifurcation and by 

implantation, one method or the other predominating in different shells. As is very 'common 

in the leptenoid genera, the striffi increase by bifurcation more commonly in the brachial valve 

than in the pedicle valve. Increase of the number of lines by implantation is more conspicuous 

in the pedicle valve. Fine concentric striffi are developed, as in Chonetes striatissimus, but they 

are generally ·inconspicuous. Four or five spines in the better-preserved mature shells are 

visible on each side of the center along the hinge line; in .younger shells there are three or four 

spines on each side. The spines are long, diverge slightly, and curve upward (backward). 

The species is commonly distinguished from Chonetes striatissimus by its depressed convexity 

and much coarser radial sculpture, though in some extreme modifications of Chonetes novascoticus 

the radial lines approach in coarseness some of the less finely sculptured modifications of Chonetes 

~triatissimus. 

Locality: Chapman sandstone; abundant on the west side of Edmunds Hill, Chapn1an 

Township, Aroostook County, Maine. A few specimens of C. striatissimus and some forms 

somewhat intermediate between the two occur here, but there app.ear to be two distinct species. 

Occasionally-found also 2-t miles west of Presque Isle Stream. 

Chonetes novascoticus Hall is an abundant fossil in the upper beds of the Arisaig series in 

Nova Scotia, from which the type specimens were derived. Ctosely r~lated forms also appear 

abundantly in a broad belt of late Silurian rocks (Pembroke formation) extending through New 

Brunswick into the Cobscook Bay district of southeastern Maine. They have been recognized in 

collections from N erepis, about 30 miles northwest of St. Johns, New Brunswick, and at numerous 

points on' Pembroke Neck, Denbow Neck, and the Edmunds shore in Cobscook Bay. 

U. S. National Museum, catalogue No. 59707. 

Comparisons.-Some specimens of Chonetes novascoticus approach in outline and ornamentation the Chonetes striatella of Dalman, from the Silurian of Europe, but the European species 

rarely has a median riblet and is appreciably more convex than C. novascoticus .. Moreover, a 

mature shell of C. striatella (11 millimeters long a11:d 20 millimeters wide) has only from 80 to 95 

striffi, and according to De Koninck 1 there are never more than 100 striffi, while in mature 

1 De Koninck, L. G., op. cit., p. 202. 

., 
MOLL USCOIDEA. 47' 

0. novascoticus, both from Arisaig and fron1 Maine, there are generally over 100 and often as 

many as 146 radial lines at the margin. Finally C. novascoticus attains a larger size than 

C. st·riatella. 

In its fairly large size, broad outline, and medium-fine surface sculpture Chonetes novascoticus 

recalls C. coronatus Hall/ C.falklandicus :Morris and Sharpe,Z C. arcei illrich, 3 C. gibbosa Kayser/ 

C. polytrichia Roemer, 5 0. hardrensis Phillips, 6 and C. melonicus Billings. 7 These species are all 

n1ore gibbous than C. novascoticus and have (except C. gibbosa, C. hardrensis, C. melonicus, and 

0. 1Jolyt1·ichia) few~r and coarser radial lines. None of these species ever show a median rib, 

and there are also other individual distinctions. 

In the depressed convexity, size, outline, and fine radial lines Chonetes comstocki Hartt 8 

resembles C. novascoticus, but the radial lines are slightly coarser. Chonetes tenuicostata 

Oehlert 9 is a si1nilar forn1, possibly identical with C. novascoticus. The French species attains . 

a length of 15 n1illimeters, a width. of 23 millimeters, and a thickness of 3 millimeters, and has 

120 to 130 radiallin.es at the margin. 

Perhaps the closest all!es are the Silurian shell, generally called Chonetes lata Von Buch or 

C. st1"iatella var. lata by European authors, and the Devonian species designated by European 

geologists Chonetes sarcinulatus Schlotheim. There has always been doubt among paleontologists as to what fossil was intended for the original of the latter species. Schlotheim's 

type was a fairly large, apparently very finely ribbed and punctate shell. A Chonetes of the 

sa.me shape, outline, and markings as Schlotheim's figures, having on the surface 100 or n1ore 

fine lines, occurs in the Lower Devonian, widely distriputed over Europe. This Chonetes has 

been identified with C. sarcinulata by De Verneuil, Von Buch, F. Roemer, Schnur, Kayser, the 

Sa.ndbergers, and others. De Koninck, 10 however, maintains that finely striate shells ought to 

be referred to C. striatella Daln1an and that the fine punctate striation of Schlotheim's fossil 

is not surface prnmnentation but a common n1ode of preservation of the internal mold of thick 

shells which, on the surface, have an entirely different ornamentation. This surface ornamentation in what De Koninck maintains to be the real C: sarcinulatus is not fine radial sculpture with 100 or 1119re lines at the n1argin but much coarser markings, amounting almost to 

plications, about 16 to 18 in number on the body of the shell and regularly bifurcating in front, 

so that on the n1argin there are about 35 very coarse, rounded lines or riblets-occasionally 

more, but conunonly less than thtLt number. To this type of Chonetes, however, the name 

C. 1Jlebeia Schnur has been given; and mnong German geologists the name Chonetes plebeia or 

Chonetes sarcin'l.t,lata var. 1Jlebeia is invariably applied to such shells as have a small number of 

coarse bifurcating radial lines or ribs, 11 whereas the nan1e C. sarcinulatus in the typical sense is 

used by the Gern1ans for the more finely sculptured Chonetes. 12 Oehlert regards as Schlotheim's 

type an insinuate Chonetes with fairly high cardinal area and with 46 to 56 strong strire, a form 

s.in1ilar to that which among the Germans is known as C. polytrichia Roemer. Roemer's types, 

however, have 150 fine strire. The American C. novascoticus may be compared with this nlultistriate forn1 of Chonetes sarcinulatus, but the European form is not sufficiently well described 

I Hall, James, Pnlcontology of New York, vol. 4, pl. 21, figs. 9-12,1867. See Schuchart, Charles, U.S. Geol. Survey Bull. 87, p. 173,1897, for 

nddltlonnlrofcronccs. 

2 Heed, F. ll. C., Brnchiopodn from the Bokkeveld beds: South African Mus. Annals, vol. 4, pl. 171, figs. 9-10, 1903. The species occurs in the 

l~n.lklo.nd Islands, Argentina, Brazil, and South Africa in Lower to Middle Devonian~ 

s Ulrich, A., Ncuos Jahrb., Beilage Band, vol. 8, p. 77, pl. 4,figs. 35,36,1892. Occurs in Middle or more probably Lower Devonian of Bolivia 

and South Africa. 

4 Kayser, Emanuel, Die Fauna dor ii.ltesten Devon-Ablagerungen des Harzes, p. 204, pl. 30, fig. 10, 1878; Lower Devonian (Kiosterholtz limestone), IIru·z Mounto.ins, Gennany. 

~Roemer, F. A., l3eitriige zur geologischen Kenntniss des nordwestlichens Harzgebirges, pt. 3, p. 115, pl. 17, fig. 3, 1853 (as Leptrena polytrichia); 

lowest Devonian ("Silurian") limestone, Klosterholtz, Harz Mountains, Germany. This species has a broad sinus in the pedicle valve. 

o Davidson, 'fhomas, British Devonian :Brachiopoda, p. 94, pl. 19, figs. 6-7; Upper Devonian, England. 

T Paleozoic fossils of Crumda, vol. 2, p. 15, fig. 6, 1874; Oriskany, Gaspe, Canada. This specie11 has a cronulated hinge line in the pedicle valve and 

belongs to the subgenus Eodevonaria Breger. 

a Hufialo Soc. Nat. Sci. Bull., vol. 1, p. 250, pl. 9, figs. 5, 14, 18, 19, 31, 1874; Lower to Middle Pevonian, Para, Brazil. 

o Oehlert, D.P., Soc. g~ol. France Bull., 3d ser., voi. 5; p. 599, pl. 10, figs. 13-13a, 1877. 

10 De Koninck, L. G., Recherches sur les animaux fossiles: 1\!on~graphie des genres Productus et Chonetes, 1847. 

II Schnur, J., Brachiopodon dcr Eifel: Pnlneontographica, vol. 3, pl. 21, fig. 6, 1853. , . 

IS Oehlert, D.P., Chonetes devoniens do l'ouestde Ia France: Soc. g~ol. France Bull., 3d Ser., vol.ll, p.119, pl. 14; fig. 2,1883. Kayser, Emanuel, 

Pamont. Inst. Univ. Wien, Bd.12, IIeft 1, pp. 28, 34, 1898 (cf. Roemer, F. A., NeuesJahrb.,1863, p. 521), Schnur, J., Palaeontographica, vol. 3, pl. 21, 

figs. 5a, 5o, 1853. 
48 FAUNA OF THE C,HAPMAN SANDSTONE OF MAINE. 

to warrant a union of the two. Chonetes sarcinulatus has 100 or more stri::e; the shell has the 

size and wide form of Chonetes novascoticus and is depressed-convex, without de:fillitely demarcated ears, median sinus, or median rib. ·. Although recognizing the strong possibility that 

Chonetes novascoticus may be identical with these European Eo-Devonian shells, it seems 

preferable for the present to retain the name Chonetes novascoticus Hall, 1860, especially 

considering the uncertainty enshrouding Schlotheim's types of Chonetes sarcinulatus. 1 

Equally apparent is the similarity and possible identity of Chonetes novascoticus with some 

Gotland late Silurian shells that have passed under the name Chonetes lata Von Buch 2 or Chonetes 

striatella Dalman var. lata. Gagel 3 has lately revived Von Buch's long unused Chonetes lata for 

a large, depressed species from Baltic late Silurian drift bowlders. These. shells have more 

than 12·5 stri::e and seem identifiable with Chonetes novascoticus, but whether Von Buch's originals conform with this type is questionable. Von Buch's contemporaries, Sowerby 4 and De 

Koninck,5 as also Davidson,~ regarded the "species" Chonetes, lata as having a maximum of 

less than 100 stri::e and as representing only a larger, wider extreme of Chonetes striatella Dalman. "Chonetes lata," as figured by Sowerby and by Davidson from the English Upper Ludlow and Tilestones, differs from Chonetes novascoticus not only in the less profuse striation but 

also in having the spines curved in the opposite direction. 

Clarke has identified with Cho1J,etes novascoticus Hall a very coarsely ribbed Chonetes 

occurring in the Silurian along Rio Trombetas, in the· State of Para, Brazil.7 This Brazilian 

species is somewhat more coarsely ribbed than C. novascoticus but agrees better with theW aldron 

form, especially in its. small size and. in the persistent presence of a n1edian rib. This form is 

closely aUied with Chonetes zephyrus Ba"rrande, from the Bohemian middle Silurian, etage E 2, 

which has medium-fine radial sculpture and a median ribl.et and is r.ather flat. 

CHONETES BASTIN! Willian1s. 

Plate VIII, figure 25. 

1886. cf. "Chonetes.allied to C. cornuta but much larger and with finer ridges, Clinton." Shaler, N. S., ·Preliminary 

report on the geology of the Cobscook Bay district, Maine: Am. Jour. Sci., 3d ser., vol. 32, p. 5~, 1886. 

1913. Chonetes bastini. Williams, U. S. Nat. Mus. Proc., vol. 45, p. 337, pl. 30, figs. 6, 7, 10. Pembroke formation, 

Leighton Cove, etc., town of Pembroke, Washington County, Maine. 

A broad, finely lineate form of Chonetes was reported by N. S. Shaler from Leighton's 

Cove as allied to C. cornuta but much larger and with finer ridges. In the collections made 

some of the specimens closely resemble Chonetes novascoticus. The more characteristic form 

is, however, more finely lineate and broader than the typical representative of C. novascoticus 

from the Arisaig rocks. To this finely lineate form the specific name bastini was applied. 

The species is similar in form to Chonetes striatella Dalman but differs in its finer and more 

num~rous surface lines and in the number of its spines. Full-grown specimens are frequ,ently 20 

millimeters wide and generally not quite 10 millimeters long. The pedicle valve is gently convex; 

beak low; spines on the cardinal margin from 12 to 16 and the radiating·lines over 100 and 

occasionally a.s many as 200 at the margin. A short median septum is generally present under 

the beak of the pedicle valve. The brachial valve is slightly concave. There is no enlarged 

median rib on the pedicle valve, but occasionally a narrow median furrow crosses the shell at 

this point. . · 

The shell differs from Chonetes novascoticus Hall in its greater transverse extension; ordinarily it is twice as wide as long. 

l The American shell identified by Norwood and Pratten (Jour. Acad; Nat. Sci. Philadelphia, vol. 3, p. 28, 1854) as Chonetes sarcinulatus Schlot- . 

heim is probably one of the forms of Chonetes coronatus occurring at the Devils Bake Oven, Ill., in beds of Hamilton age. ' 

i Von Buch, L., Ueber die Silicification organischer ·Korper, nebst eirligen anderen Bemerkungen tiber wenig bekannte Verstcineru.ngen: K. 

Almd. Wiss. Berlin Abh. (for 1828), pp. 53, 70, pl. 3, figs. 1, 3, 5-9, 14, 15, 1831. 

a Gagel, C., Die Brachiopoden der cambrischen und silurischen Geschiebe im Diluvium der Provinzen Ost- und West-Preusscn: Beitr. Naturh. 

Preuss., No. 6, 1890. · · 

4 Sower by, J. de C., in Murchison, R. I., Silurian system, pp. 603, 610, pl. 3, figs. lOb, 12c; pl. 5, fig. 13, 1839. 

5 De Koninck, L. G., Monographic des genres Productus et Chonetes, p. 200, pl. 20, fig. 5, Liege, 1847. 

a Davidson, Thomas, Monograph of the British fossil Brachiopoda, pt. 7,'The Silurian Brachiopoda, p. 331, pl. 49, figs. 23,24 (not 25 or 26), 1870. 

1 Clarke, J. M., Mus. Naccional, vol.lO, p. 24, pl. 50, fig. 25, Rio de Janeiro, 1899 (author's English ed., p. 12, 1900). 
• 

MOLL USCOIDEA. 49 

Locality: Pembroke forn1ation, Leighton Cove, Long Cove, nnd in many other localities 

in the town of Pembroke, :Maine. 

U.S. National :Museum, catalogue Nos. 58960, 58961, and 59926. 

CrroNETES NOVASCOTICUS Hall var. CANADENSIS Billings. 

Plate JX, figures 20, 21i Plate .X, figures 30, 31i Plate XI, figure 1G. 

1874. Chonetes canadensis. Billings, Paleozoic fossils, vol. 2, pt. 1, p. 17, figs. 17. 

Lower Devonian: Perce, Bay de Chale1us, Quebec. 

1883. Chonetes canadensis. Ells, Canada Geol. Survey Rept. Progress for 188o-1882, p. 9DD. 

Gaspe upper limestones (Oriskany): Perce Rock, G~spe, Quebec. 

1885. Chonetes canadensis. Ells, idem, 1882-1884, p. 24E. 

Gaspe Oriskany [whether limestone 01: sandstone is not stated]: Hills in the rear of Gaspe Village, Quebec. 

1907. Chonetes impensus. Clarke, New York State Mus. llull. 107, p. 263, fig. 

JJower Devonic [Moose River sandstone]: Moosehead, 7 miles north of Kineo, Somer:;et County, Main~. 

Chonetes canadensis Billings was described as a large, nearly flat Chonetes; transversely 

extended, semicircular or semielliptical in outline, and covered with radiating strire, of which 

there are·10 to 15 in the width of two lines (12 to 18 in 5 millimeters). A large Chonetes presenting these characters is common at Detroit, Maine. It is represented in its different expressions by the five specimens figured, which have the following meas~ements: 

Dimensions of specimens of Chonetes canadensis. 

Specimen Length Width Radial lines 

Plate. Figure. in 5 No. (millimeters). (millimeters). millimeters. 

765 IX 21 24:5 44.5 14-15-18+ 

635 X 30 18. 75 '39. 5 a 12-15-16+ 

767 IX 20 18 28 14-16-

641 X 31 21 37.5 15-24-

763 XI 16 24.5 44 14-15-17-

a No. 635 has about 170 lines at tho margin. Note tho median rib on this specimen (a brachial valve) and tho radial lines curving inward. 

Both those features seem to be duo to an injury to tho shell. The same features appear in Chonetes impensus Clarke. 

These specimens represent a very variable species, if, indeed, they are cospecifi.c. Specimen 

No. 635 (Pl. XX, fig. 30) is a slightly convex brachial valve; specimen No. 641 (Pl. X, fig. 31) 

is a slightly concave brachial valve; the other three specimens are pedicle valves of slight but 

varying convexity. No two of the five specimens have quite the same expression. They 

answer fairly well, how.ever, to Billings's description of 0. canadensis and are include~ under 

that species as a variety of 0. novascoticus. T~e Maine forms are larger than any of Billings's 

specimens, the largest of which were 12 by 20, 12 by 22, and 14 by 24 millimeters. Specimens 

Nos. 765, 767, and 763 seem to be only large individuals of Chonetes novascoticus, and the general 

resemblance of the Canadian form to I-Iall's species leads to the conclusion that it is a variety. 

That 0. canadensis is only n, large . varietal modification of 0. novascoticus ·has already been 

suggested.1 

Locality: Moose River sn,ndstone, Detroit, Maine. This type of shell does .not occur in the 

·.Chapman sandstone. 

U. S. National Museun1, catalogue No. 59708. 

CnoNETES VICINUS var. DEFLECTUS Hall. 

Plate III, figure 8. 

1843. Leptrena vicina. Castelnau, Essai sur le systeme silurien del' Amerique septentrionale, p. 39, pl. 14, fig. 9. 

Formation(?): Ontario County, N.Y. · 

1843. Stro])/wmena 7nucronata. Hall, Geology of New York, Rept. Fourth Dist., pp. 180-181, fig. 3. 

Marcellus shale: Avon, Indian reservation, Erie County, N.Y. 

t ~Villlams, H. S., and Gregory, H. E., Contributions to the geology of ~aine: U. S. Geol. Survey Bull. 165, P!l· 84, 85, 1900. 

5024[1°--~0.89--16----4 
• 

50 FAUNA OF THE CHAPMAN SANDSTONE OF MAINE. 

1854~ Chonetes armata. Norwood and Pratton, Acad. Nat. Sci. Philadelphia Jour., vol. 3, p. 28. 

Hamilton limestone: Bake Oven, Ill. 

1857. Choneteslaticosta. Hall, New York State Cab. Nat. Hist. Tenth Ann. Rept., p. 119. 

Corniferous limestone: A few miles southeast of Buffalo, N.Y. 

Hamilton shales: Canandaigua, N. Y. 

Hamilton limestone: Devils Bake Oven, Jackson County, Ill. (associated with Chonetes coronatus and C. 

pusilla). 1 

1857. Chonetes gibbosa. 'Hall, idem, p. 145. 

Hamilton group: York, Livingston County, N.Y. 

1857. Chonetes deflecta. Hall, idem, p. 149. 

Hamilton group shales: Canandaigua Lake, N.Y. 

1857. Chonetes pusilla. Hall, idem, p. 149. 

Hamilton limestone: Devils Bake Oven, Ill. 

1867. Chonetes mucronata (pars). Hall, Paleontology of New York, vol. 4, p. 124, pl. 20, fig. 2, pl. 21, fig. 1. 

Marcellus shale: A von, Livingston County; Crooked Creek, near Darien, Genesee County; and Alden, Erie 

County, N.Y. 

1867. Chonetes laticosta. Hall, idem, p. 125, pl. 20, figs. 1a-ld. 

Corniferous limestone: Manchester, Ontario County; in Erie County on the Indian reservation south~ast of 

Buffalo; and at Williamsville and Clarence Hollow, N. Y. 

Hamilton: Pratts Falls and other localities in Onondaga and Madison counties, N. Y. 

1867. 'Chonetes deflecta. Hall, idem, p. 126, pl. 2, figs. 7, 8. 

Hamilton group shales: Canandaigua Lake, Ludlowville and Kidders Ferry on Cayuga Lake, Moscow, York, 

Covington, and other places in western New York. 

1867. Chonetes pusilla. Hall, idem, p. 128, pl. 21, fig. 6. 

Hamilton limestones: Bake Oven, Ill. 

1868. Chonetes pusillus. Meek, Chicago Acad. Sci. Trans., vol. 1, p. 93, pl. 13, fig. 2. 

Middle Devonian: Fort Resolution, Great Slave Lake, British America. 

1874. Chonetes mucronata. Nicholson, Paleontology of the Province of Ontario, p. 74. 

Corniferous limestone: Ramas Farm, near Port Colborne, Ontario. 

1874. Chonetes laticosta. Billings, Paleozoicfossils, vol. 2, pt. L, p.·20. 

Gaspe limestone No.8: Little Gaspe, Grande Greve,. and Indian Cove, Gaspe, Quebec. 

1878. Chonetes mucronatus. Ashburner, Pennsylvania Second Geol. Survey Rept. F, p. 223. 

Upper Hamilton: sandstone: Aughwick Valley and end of Jacks Mountain, Huntingdon County, Pa. 

1883. Chonetes mucronatus. I. C. White, Pennsylvania Second Geol. Survey Rept. G7, ·pp. 76, 230. · 

Marcellus shale: Little Fishing Creek, Hemlock Township, Columbia County, Pa. 

1883. Chonetes mucronata. Hall, New York State Geologist Second Ann. Rept., pt. 47, figs. 6, 7. 

Marcellus shale: West Avon, Livingston County, N.Y. 

1883. Chonetes deflecta. Hall, idem, pl. 47, fig. 28. 

Hamilton group: Western New York. 

1883. Chonetes laticosta. Ells, Canada Geoi: Survey Rept. Progress for 1880-1882, p. 13DD. 

Upper Gaspe limestones (Oriskany): Indian Cove, Grande Greve, and Little Gaspe; Gaspe Bay, Quebec. 

1884. Chonetes deflecta. Walcott, U. S. Geol. Survey Mon. 8, p. 124, pl. 2, fig. 8. 

Lower part of Nevada limestone (Lower Devonian): Combs Peak, west slope of County Peak, and lower beds 

at Lone Mountain, 18 miles northwest of E.ureka, Nev. 

Upper Devonian: Rescue Hill, Eureka district, Nev. 

1884. Chonetes mucronata (?). Walcott, idem, p. 124. 

Upper part of Nevada limestone (Upper Devoniar.): Foothills east of Sentinel Mountain and the Sugar Loaf, 

Eureka district, Nev. · 

1884. Chonetes macrostriata (pars). Walcott, idem, p. 126, pl. 13, fig. 14b (not figs. 14, 14a, 14c; not pl. 2, fig. 13). 

Lower Devonian limestone: Combs Peak; .south spur of Atrypa Peak; on the divide of Rescue and Berry 

canyons; and midway of Grays Canyon, Eureka district, Nev.; also at north end of Ravens Nest, Pinon 

Range,· Nev. 

1885. ·Cho'netes mucronata. Claypole, Pennsylvania Ser;:ond Geol. Survey Rept. F2, p. xiii. 

Hamilton (upper shales): Perry County, Pa. . 

1889. Chonetes mucronatus. Claypole, Pennsylvania Second Geol. Survey Rept. 03, p. }57. 

Upper Hamilton shale: Brickfield, 1 mile southwest of New Bloomfield, Perry ColPlty, Pa. 

1889. Chonetes mucronata. Simpson, idem, pp. 212-213, 216. 

Hamilton formation: Marshalls Creek; Monroe County, Pa. 

1889. Chonetes allied to mucronata. Schuchert, New York State Geologist Eighth Ann. Rept., p. 52. 

Oriskany: Cayuga, Canada West. . 

1892. Chonetes mucronata. Hall and Clarke, Paleontology of New York, vol. 8, pt. 1, pl. 16, figs. 6, 7. 

Marcellus shale: West Avon, Livingston County, N.Y. 

1 In the detailed section of the Devils Bake Oven given by Weller, in 1897, no two of these three species are recorded as associated together. 
J 

1 

MOLLUSCOIDEA. 

·1892. Chonetes deflecta. Hall and Clarke, idem, pl. 16, fig. 28: 

Hamilton group: Western New York. 

1894. Chonetes 1nucronat'lts. Prosser, U. S. Geol. Survey Bull. 120, pp. 4, 19, 20, 21, 28, 35, 37. 

:Marcellus shale: Near Scott Street Bridge, Stroudsburg, Pa. 

51 

Hamilton group: Lehigh Valley Railroad cut north of Bowmans, Carbon COlmty, Pa.; roadside, ha1f a mile 

north of l\{arshalls Falls post office, and in Marshalls Creek at the falls, Monroe County, Pa.; Saw kill Creek, 

above the falls, Pike County, Pa..; and Rose Point, Orange.County, N.Y. 

1894. Chonetes deflccta. Prosser, idem, pp. 5, 8, 21. 

Hamilton group: Gravel Place, Brodhead Creek, and Marshalls. Falls, Monroe County, Pa. · 

1897. Chonetes mucronal'l.ts. Schuchert, U. S. Geol. Survey Bull. 87, p. 176. 

Oriskany and Hamilton: New York; Cayuga, Ontario; Gaspe, Quebec; Eureka district, Nev. 

1897. Chonetes pusill'lts. Schuchert, idem, p. 177. 

Hamilton: Bake Oven, Ill.; Fort Resolution, Great Slave Lake, British America. 

1897. Chonetes vicinus. Schuchert, idem, p. 180. 

Hamilton: Ontario County, N.Y.; Columbus, Ohio. 

Wisconsin: Eureka district, Nev. 

1897. Stropheodonta macrostriata (pars). Schuchert, idem, p. 424. 

Lower Devonian: Eureka district, Nev. 

1897. Chonetes laticosta. Weller, .Tour. Geology, vol. 5, No.6, pp. 626, 627. 

Lower part of Upper Helderberg group/ Devils Bake Oven, near Grand Tower, Jackson County, Ill. (zones 

1, 2, 4). 

1897. Chonetes mucronatm. Weller, idem, pp. 628-630. 

Corniferous limestone: Devils Bake Oven, near Grand Tower, Jackson County, Ill. (zones 6, 7, 11, 13). 

1897. Chonetes deflecta. Weller, idem, pp. 630, 631. 

Corniferous-Hamilton transition: Devils Bake Oven, near Grand Tower, Jackson County, Ill. (zones15, 16, 23). 

1897. Chonetes pusill1.ts. Weller, 2 idem, pp. 631, 634. · 

Corniferous-Hamilton transition: Devils Bake 0\ren, near Grand Tower, Jackson County, Ill: (zbne 23). 

1897. Chonetes pusill1.ts. Schuchert, U. S. Geol. Survey Bull. 87, p. 178. 

Hamilton: Bake Oven, Ill.; Fort Resolution, Great Slave Lake, British America. 

1898. Chonetes nt'l.teronatus (?). Bownocker, Denison Univ. Sci. Lab. Bull., vol. 11, pl. 6. 

Corniferous limestone: Deer Creek, Columbus, Marble Cliff, Marion, Sandusky, Kellys Island, vVhite House, 

and Bellefontaine, Ohio. · 

1899. Chonetes m,ucronatus. Prosser, New York State Geologist Seventeenth Ann. Rept. (for 1897), p. 353. 

Marcellus black shale: Near·Clarkesville, Albany County, N.Y. 

1899. Chonetes deflecta. Prosser, idem, p. 353. 

Hamilton sandy shales: Near Clarkesville, Albany County, N.Y. 

1899. Chonetes ntucronatus. Schuchert, Am. Jom. Sci., 4th ser., vol. 7, p. 431. 

Oriskany chert: Camden, Benton• County, Tenn. · 

1900. Chonetes mucronatus. Schuchei·t, Geol. Soc. America Bull., vol. 11, pp. 293, 321, 325. 

Oriskany: Camden, •renn.; Cayuga., Canada. 

1901. Chonetes mttcronatns. Clarke, New York State Mus. Bull. 49, pp. 115, 129, 132,.134. 

Stafford limestone lenticle: Western New York. 

Marcellus thale below the Stafford limestone: Livonia salt shaft and Lancaster, N. Y. 

1901. Chonetes dejlect'l.tS and cf. de.flectus. Clarke, idem, p. 136. 

Calcareous lenses in Marcellus shale: Livonia salt shaft, Livonia, N. Y. 

1901. Chonetes mucronatus. Wood, New York State Mus. Bull. 49, pp. 142-144, 146-152, 158. 

Stafford li.mestone and Marcellus shale below Stafford limestone: Lancaster, Erie County, N.Y. (in all the zones). 

1902. Chonetes vicin'l.ts. Monroe, Wisconsin Nat. Hist. Soc. Bull., vol. 2, No.1, p. 65. 

Hamilton group: East Bethany, Genesee County, N. Y. 

1904. Chonetes robustus. Raymond, Am. Jour. Sci., 4th ser., vol. 17, p. 289, pl..17, figs. 1, 2. 

Hamilton (Moscow) shales: Monteth Point, Canandaigua·Lake, N.Y. 

1904. Chonetes mucronatus. Raymond, idem, p. 289, pl. 15, rows 4 and 5 .. 

1\:loscow (Hamilton) shales: Monteth Point: Canandaigua Lake, N. Y. 

1907. Chonetes billingsi. Clarke, New York State Mus. Bull. 107, p. 266, figs. on p. 267. 

Lower Devonic: Grande Greve, Quebec. 

1\Hddle Devonic: Gaspe Basin, Quebec. 

Shell sn1n.ll; convexo-concave; outline transversely quadrate or semicircular. Pedicle 

vitlve strongly convex, a valve 7.2 millimeters long and 12 millimeters wide being 1.6 n1illimeters 

thick. Gren.test convexity in the middle; profile arcuate from beak to front; ears flattened. 

Con1n1oJuy the proportion of width and length is abollt as 4 to 3. The hinge line is equal to 

1 Probably equivalent to tho "zone of Spirifer hercynite" or Grande Greve !Uld York River beds of Gaspe and M:oose River sandstone of M:aine. 

2 Weller reiterates hero. that "Chonetes dejlecta and Chonetes puRiUa * * * are· apparently variations of a single species." 
52 FAUNA OF THE CHAPMAN SANDSTONE OF MAINE. 

the greatest width, the sides are subparallel, straight, and curve into the front margin, which 

is widely and shallowly arcuate. A me9.ian septum on the interior extends from the beak 

about one-quarter the length; the brachial valve is strongly concave. 

The surface is marked by very coarse flexuous ribs, of which there are commonly about 15 

near the beak; they increase at first chiefly by implantation, and in front by both implantation 

and bifurcation. These ribs number about 28 or 30 at the front margin of a shell 7 n1illimeters 

long. In the umbonal region the ribs are wider than the interspaces and there are 9 to 11 ribs 

in 5 millimeters; in front the interspaces are as wide as or slightly wider than the ribs. No 

spines were observed on the specimens, but the general expression of the shells places them 

evidently in the genus Chonetes. · 

Locality: Moose River sandstone, Little Brassua Lake, Somerset County, Maine (local-. 

ity 1061 B 1). It is associated with Leptostrophia blainvillii Billings (=L. perplana Conrad), a 

crushed Spirifer not unlik~ Spirijer murchisoni Castelnau, and a bivalve. In the Chapman 

fauna no Chonetes of this coarsely marked type is known to occur. 

U. S. National Museum, catalogue No. 59709. 

Remarks.-The Chonetes vicinus type represents in America, as does the Chonetes plebeia 

Schnur in Europe, an expression of Chonetes which differs from the ordinary smaller forms of 

Chonetes in its greater gibbosity and more particularly in the coarseness and sparsity of its radial 

lines, which amount, in fact, to ribs., or rib lets rather than lines. Species of Chonetes of this 

expression have been given various names, but appear to constitute a species-group or gens to 

which the name Chonetes vicinus of Castelnau is applicable. Chonetes vicinus usually n1anifests 

itself in the ~ollowing modifications, the characters of which are fl11ctuating and not fixed: 

1. Variety a, or rnucronatus type; ribs simple, rigid, 20 to 24, occasionally up to 30. 

2. Variety b, or laticosta type; ribs flexuous, increasing rather freely in number by implantation and by bifurcation, 

12 to 25. 

3. Variety c, or dcjlecta type; ribs as in the laticosta type, but 26 to 30 and rarely up to 34 in number. 

4. Variety d, or gibbosa type; ribs as in the laticosta and dejlecta types, but the shells are large and gibbous and with a 

minimum of 30 to 40 ribs. · 

Chonetes vicinus and its European equivalent, Chonetes plebeia, are valuable horizon 

markers. Chonetes plebeia appears to be unknown in the Taunusian or zone of Spirijer 

primrevus, but it becomes conspicuous ill the oyerlying Lower Coblenzi.an or zone of Spirifer 

hercynire, and continues into the Upper Coblenzian and Meso-Deyonian. In North America the 

Chonetes vicinus ·type is conspicuous in the zone of S pirijer hercyn ire (C. gaspensis, etc.), represented by the Moose Rivei:, Grande Greve, andY ork River beds, and continues into the Onondaga 

and Meso-Devonian, the gibbosa. type continuing on from the Upper Hamilton into the Ithaca 

shale member of the Portage formation of the Neo-Devonian. In the Oriskany, as in the Taunusian of Europe, the Chonetes vicinus type is not definitely known, and in the Helderberg there is 

no indication of its occurrence. 

Subgenus EODEVONARIA Breger. 

For the Chonetes having denticulate hin·ge margin Mr. Breger 1 proposed the name Eodevonaria, taking for the type some specimen~ of Chonetes arcuatus Hall from· the Moose River 

sandstone. To this subgenus six previously knov.rn species conform, namely, (1) Chonetes 

arcuatus Halt, from the "Corniferous" of Ohio, Indiana,_New Jersey, and New York; specimens 

from the Moose River sandstone at Little Brassua Lake, Somerset County, l\1aine, are also 

referred to this species; (2) Chonetes dilatus F. Roemer, Lower and Middle 0) Devonian; (3) 

Chonetes melonicus Billings, Grande Greve limestone of Little Gaspe, Quebec; (4) Chonetes 

acutiradiata Hall, "Corniferous" limestone of Williamsville, Erie County, N. Y.; (5) Chonetes 

extensus Kayser, Lower Coblenzian of the Rhenish Devonian; and (6) Chonetes arcei A. Ulrich, 

Lower Devonian of Bolivia, Argentina, and South Africa. It is evident, therefore, that the subgenus is characteristic of the Lower Devonian over a wide geographio range. Stratigraphically it 

is nowhere known to pass below the Oriskany nor to range upward into distinctly MesoDevonian faunas. Chonetes of the type_of Eodevonaria do not occur in the Chapman sandstone, 

• Breger, C. L., On Eodevonaria, a new subgenus of Chonetes: Am. Jour. Sci., 4th ser., vol. 22, p. 534," 1906. 
MOLL USCOIDEA. 53 

but the species Eodevonaria arcuatus occurs in the Moose River sandstone of central :Maine. 

Chonetes melonicus Billings is reported by Clarke from the upper beds of the Grande Greve limestone. Clarke found no crenulations in the specimens of Chonetes hudsonicus from Becraft 

Mountain, but observed them as a distinct feature of the shells from the Gaspe (York River) 

sandstones of Gaspe, which he called 0. hudsonicus metatype gaspensis. 0. hudsonicus· metatype 

gaspensis has also been recognized in the Spirifer·arenosus fauna at St. Helens and Cote St. Paul, 

near :Montreal. 1 

CHONETES (EODEVONARIA) ARCUATUS Hall. 

Plate III, figures· 6, 9, 11. 

1857. Chonetes arcuata. Hall, New York State Cab. Nat. Hist. Tenth Ann. Rept., p. 116. · 

Corniferous limestone: New York. 

1867. Chonetes arcuata. Hall, Paleontology of New York, vol. 4, p. 119, pl. 20, fig. 7. 

Corniferous limestone: Near Williamsville· and Clarence Hollow, Erie County, N.Y. 

1883. Chonetes arcuata. Hall, New York State Geologist Second Ann. Rept., pl. 47, figs. 15, 35, 36. 

Corniferous limestone: Near Williamsville, Erie County, N.Y. 

1892. Chonetes arcuata. Hall, Paleontology of New York,. vol. 8, pt. l, pl. 16, figs. 15, 35, 36. 

Corniferous limestone: Near Williamsville, Erie County, N. Y. · 

1897. Chonetes arcuatus. Schuchert., U. S. Geol. Survey Bull. 87, p. 172. 

Comiferous limestone: Wmiamsville, Clarence Hollow, etc., New York, Columbus, Ohio. 

1900. Chonetes arcuatus. Kindle, Indiana Dept. Geology and Nat. Res. Twenty-fifth Ann. Rept., p. 601, pl. 4, figs. 

6, 6a. 

J effm·sonville {" Corniferous ") limestone: Paris Crossing, Incl. 

1903. Chonetes arcuatus. Weller, Paleontology of New Jersey, vol. 3, pp. 103, 105, 367, 373, pl. 51, figs. 18, 21. 

Corniferous limestone: Road along Delaware River, l! miles southwest of Peters Valley, N.J. 

Newfoundland grit: West of Greenwood Lake, N. J. 

1906. Chonetes (Eodevonaria) arcuatus. Breger, Am. Jour. Sci., 4th ser., vol. 22, p. 534. 

Upper Helderberg group: Ohio, Indiana, New Jersey, and New York. 

Moose H.iver sandstone: Little Brassua Lake, Somerset County, Maine. 

Shell small to medium-sized, convexo-concave, very gibbous. Ratio of length and breadth 

varying from 9.10 to 7.10; greatest width along the hinge line; the sides of the shell are straight 

for some distance below the hinge and curve into the front margin, which is- semicircular; the 

pedicle valve is very gibbous, the depth being equal to about a third of the length. The shell 

is inflated in the middle, which includes the greatest convexity; the umbo is gibbous and the 

beak protrudes over the hinge line. The ears are somewhat flattened and small. They are 

demarcated on the interior by a ridge (a crural ribbon?) which curves· about and includes the 

inflated po.rtion of the shell. A faint narrow n1edian sinus occurs occasionally in the pedicle 

valve. On the interior of the valve a thin median septum extends one-third to one-half the 

length fr01n the beak. Brachial valve not seen. 

The surface is marked by straight, slightly fle~uous radial lines which increase frequently 

by bifurcation. On specimens 10.5 millimeters long there are fron1 72 to 84 lines at the margin 

nnd fron1 19 to 24 in the space of 5 n1illimeters on the front part of the shell.. The lines also 

cover the. ears. In some internal molds the radial lines· are sharply expressed, nearly as well 

developed us on the surface; in other specimens the ornamentation is preserved only in spots, 

and the· internal n1old is for the greater part radially pustulose. On all internal molds the 

ornttnlentation on the un1ho near the beak is obsolescent. The hinge is dentieulate in all 

three of the internal molds of the.pedide valve in which the hinge is visible. 

Dimensions of specimens of Chonetes (Eodevonaria) arcuatus. 

No. Length Width DeptP. Hadial lines. (millimeters). (millimeters). (millimeters). 

5052.1 10.5 11.5 3 24 in 5 millimeters; 84 around the margin. 

5052.2 10.5 15 3 

5052.4 10.5 12 4 19 in 5 millimeters; 72 around the mar[,rin. 

1 Wllllruns, H. S., On tho fossilfaunns of St. Holen's breccia: Roy. Soc. Canada Trans., 3d ser., vol. 3, pp. 217-239,1909-10. C. hudsonicus meta. 

type gaspensts has also been recognized in the Spirifer arenosus fauna at St. Helens and Cote St. Paul, near Montreal. 
54 FAUNA OF THE CHAPMAN SANDSTONE OF MAINE. 

The species is easily recognized by its inflated gibbosity, medium fine radial sculpture, 

denticulations on the hinge, and slight difference· between length and width;. The :Maine specimens correspond with forms of C. arcuat·ns figured by Weller 1 from the "Corniferous" limestone of New Jersey. · 

Locality: Little Brassua Lake, Somerset County, Maine. No representative of this species 

or of Eodevonaria has been discovered in the Chapman fauna proper. 

U.S. National Museum, catalogue No. 59710. 

Oomparisons.-In its superficial characters Chonetes (Eodevonaria) arcuatus resembles fossils 

identified by authors and apparently also by Hall with the Chonetes hemispherictts of I-Iall 

(? Strophemena gibbosa Conrad, 18~1); but the present species has a denticulated hinge, a 

character which is usually regarded· as of generic value among the strophomenoids and leptrenoids. This denticulated hinge occurs in 0. melonicus Billings and also in C. acutiradiatus Hall, 

which is closely allied to C. hemisphericus Hall, but. in the last-named species this character, so 

far as known, does not occur. The types of Chonetes hemisphericus are· much n1ore coarsely 

lined and are larger shells than the :Maine fossils under discussion. Hall says that Chonetes 

arcuatus "is distinguished from C. hemisphe1'icus by being a little less prominent on the un1bo, 

and by the shallow sinus, as well as the more numerous and much finer striro. The cast does 

not preserve the marks of the strire so conspicuously, while the surface is more abundantly 

pitted without being sensibly arranged in distinct lines." 2 

The Jewett eollection in Cornell University, which was largely used in the preparation of 

Hall's works on New York paleontology, contains specimens of 0. hemisphericus and C. arcuatus 

that controvert these statements. A hirge Chonetes arcuatus in that collection. is more gibbous 

on the umbo than C. hemisphericus, and the same may be said of a specimen figured by Weller 3 

compared with average specimens of C. hemisphericus. Many specimens of C. hemisphe1'icus 

also have a shallow sinus, which is commonly wanting in C. arcuatus front New York, New 

Jersey, and Maine. C. hemispheric1ts in one of its forms has very fine radial lines. 0. arcuatu.s 

is also occasionally regularly striate on the in~erior, but C. hemisphericus is occasioJ?-ally obscurely 

papillose on the interior. The Jewett collection contains a small, finely striate form of 0. 

hemisphericus, with less gibbous umbones than usual, from the Onondaga ("Corniferous ") 

lirnestone of Erie County, N. Y. On one of these specimens, which is hardly distinguishable 

from the ~1aine form, there are indications of what n1ay prove to be denticulations on the hinge. 

If a denticulated hinge· line could be proved in 0. hemisphericus, there need be no hesitancy in 

1;1niting 0. arcuat·us with it. There is some doubt, however, as to whether these finely striate 

specimens ought to be identified with 0. hemisphericus, for the· types of that fossil preserved in 

the American Museum of Natural History in New ·York are a coarsely striate large species. 

The large forms of Chonetes macrostriatus Walcott very much resemble 0. arcuatus in size, 

contour, and outline, and in the method of preservation of the ornamentation; but Walcott's 

species has fewer and coarser ribs.. According to Schuchert,4 who places Walcott's species in 

Stropheodonta, a denticulated hinge is present; but whether this denticulated hinge occurs in 

the real Chonetes figured by Walcott 6 on his Plate XIII or on the different shell shown on. his 

Plate II is unknown at present. If Chonetes macrostriatus Walcott really has a denticulated 

hinge, its association will be with 0. arcuatu.s rather than with 0. vicinus var. In the European 

fauna an equivalent of 0. arcuatus is found in the species Chonetes dilatata F. Roemer, a shell 

of wide distribution in the Lower Devonian of Germany, Belgium, and England. This European 

form has a denticulated hinge· and can be distinguished from the American species only 

with difficulty. The large individuals of 0. dilatata have, according to De Koninck, as many 

as 160 to 170 strire at the n1argiri. The large American forms have perhaps half that number 

and the ribs are coarser. The lJlOre finely striate American types are smaller shells and more 

finely striate on the umbones. 

l Weller, Stuart, Paleontology of New Jersey, vol. 3, 1903, pp. 103, 105, 367, 373, pl. 51, figs. 18, 21. 

s Paleontology of New York, vol. 4, p. 120, 1867. 

a Paleontology of New Jersey, vol. 3, pl. 51, fig. 21, 1903. 

4 Schuchert, Charles, A synopsis of American fossil Brachiopoda: U.S. Geol. Survey Bull. 87, p. 424, 1897. · 

a Walcott, C. D., Paleontology of the Eureka district [Nevada): U.S. Geol. Survey Mon. 8, p. 126, 1884. 
MOLL USCOIDEA. 55 

Genus CHONOSTROPIDA Hall and Clarke. 

The genus Chonostrophia was proposed. by Hall and Clarke1 for brachiopods having· the 

general characters of Chonetes but with reversed convexity of the valves at maturity, displaying 

wha~ is known as "resupinate curvature." Chonetes reversa Whitfield, an American Onondaga· 

(" Corniferous ") species, was taken as the type. · 

A single species, 0. helderbergire Hall, is reported from the Helderberg group in New York. 

With this exception the genus Chonostrophia is confined to the Oriskany and Onondaga ("Corniferous ") faunas of North and South America, where it is common and widespread. In 

Europe, Africa, and Australasia, Chonostrophia is not known to occur. The genus is also 

unknown in the Chapman sandstone fauna, though it is present in the Moose River sandstone. 

CHONOSTROPHIA COMPLANATA (Hall). 

Plate X, figure 4. 

cf.? 1846. Orthis tenuis. Morris and Sharpe, Geol. Soc. London Quart. Jour., vol. 2, p. 275, pl. 10, fig. 4; pl. 11, fig. 4. 

Lower Devonian; Falkland Islands. 

1857. Chonetes complanata. Hall, New York State Cab. Nat. Hist. Tenth Ann. Rept., p. 56. 

Oriskany sandstone: Albany and Schoharie counties, N.Y. 

1859. Chonetes complanata. Hall, Paleontology of New York, vol. 3, p. 418, pl. 93, fig. l. 

Oriskany sandstone: Albany and Schoharie counties, N. ·Y. 

1874. Chonetes dawsoni. Billings, Paleozoic fossils, vol. 2, pt. 1, p. 18, fig. 8. 

Gaspe limes~one [Grand Greve]: Split Rock, (Perce), Quebec. 

Gaspe sandstone [York River]: Gaspe, Quebec. 

1876. Chonetes complanata. Barrett, Lyceum Nat. Hist. New York City Annals, vol. 11, p. 296. 

"'l'rilobite beds" [basal Oriskany or Helderberg transition]: Bennett's quarry, Port Jervis, N.Y. 

1877. Chonetes complanata. Barrett, Aill;. Jour. Sci., 3d ser., vol. 13, p. 386. 

Trilobite beds; Bennett's quarry, near Port Jervis, N.Y. 

1883. Chonetes complanata. Hall, New York State Geologist Second Ann. Rept., pl. 47, figs. 13, 29. 

Oriskany sandstone: Albany County, N. Y. 

1883. Chonetes dawsoni . . Ells, Canada Geol. Survey Rept. of Progress for 1880-1882, p. 9DD. 

Upper Gaspe Limestone (Oriskany): Perce Rock, Quebec. 

1889. Chonetes complanata. Schuchert, New York State Geologist Eighth Ann. Rept., p. 52. 

Oriskany: Cumberland, Mel.; New York; Cayuga, Canada West. 

1889. Chonetes complanata. Lesley, Pennsylvania Second Geol. Survey Rept., pt. 4, p. 125. 

Stormsville shale, upper part of Lower Helderberg group ["Trilobite beds"]: Delaware River, Pennsylvania 

(near Port Jervis, N.Y.). 

1892. ChonostroJ>hia complanata. Hall and Clarke, Paleontology of New York, vol. 8, pt. 1, p. 311, pl. 16, figs. 13, 29. 

Oriskany sandstone: Albany County, N.Y. · 

1892. Chonostrophia sp. nov. Clarke, Am. Jour. Sci., 3d ser., vol. 44, p. 413. 

Lower Oriskany: Becraft Mountain, Columbia County, N. Y. 

1892. Chonostrophia dawsoni. Hall and Clarke, Paleontology of New York, vol. 8, pt. 1, p. 311. 

Oriskany: Gaspe, Canada. 

·1897. Chonostrophia c01nplanata. Schuchart, U.S. Geol. Survey Bull. 87, p. 180. 

Oriskany: Albany and Schoharie counties, N.Y.; Cayuga, Ontario; Cumberland, Mel.; ?Bolivia. 

1897. Chonostrophia dawsoni. Schuchert, idem, p. 180. 

Lower Devonian: Gaspe. and Perce, Quebec. 

1897. Chonostrophia sp. Kayser, Deutsch. geol. Gesell. Zeitschr., vol. 49, p. 301, pl. 10, fig. l. 

Lower-Middle Devonian: Cerro del Fuerte, Argentine. 

1900. Chonostrophia c01nplanata. Schuchert, Geol. Soc. America Bull., vol. 11, pp. 313, 324. 

Monterey (Oriskany) sandstone: Cumberland, Mel. 

Oriskany: Oneida and North Cayuga townships, Ontario. 

1900. Chonostrophia complanata. Clarke, New York State Mus. Mem., vol. 3, No.3, p. 50, pl. 7, figs. 7-13. 

Oriskany: Becraft Mountain, Columbia County; half a mile southeast of Rondout Creek near Kingston, N. Y. 

1901. Chonostrophiajervensis. Schuchert, Am. Geologist, vol. 28, p. 250, figs. c, d. 

Becraft limestone ["Trilobite beds"]: Port Jervis, N.Y. 

1903. Chonostrophiajervensis. Weller, Paleontology of New Jersey, vol. 3, pp. 94, 95, 326, pl. 42,.figs. 1, 2. 

"Trilobite beds" (lowest Oriskany): Near Nearpass Quarry and at Peters Valley, N.J. 

1 Hall, James, and Clarke, J. M., Paleontology of New York, vol. 8, pt. 1, p. 310, 1892. 
56 FAUNA OF THE CHAPMAN SANDSTONE OF MAINE. 

1903. Chonostrophia complanata: Weller, idem, pp. 100, 101, 348, pl. 46, fig. 12. . 

Spirifer murchisoni zone for upper member. of the Oriskany: 1! ~iles north of Layton, three-fourths of a mile 

west ofLayton, and at Peters Valley, N. J. 

· 1903. Chonostr.ophia complanata. Van Ingen and Clarke, New York State Mus. Bull. 69, pp. 1203, 1206. 

Oriskany siliceous limestone: Glenerie and Rondout, N.Y. 

1905. Chonostrophia complanata. Clarke, New York State Mus. Bull. 80, pp. 143, 145. 

Grand Greve limestone: North side of Gaspe Bay and at Perce Rock, Gaspe, Quebec. 

1905. Chonostrophia dawsoni. Clarke, idem, p. 145. 

Gaspe sandstone [York River beds]: Gaspe Bay, Quebec. 

1905. Chonostrophia ·jervisensis. Shimer, idem, pp. 185, 188, 199,· 226, 227, 228, 232, 234, 243, 263. 

Upper New Scotland limestone ["Trilobite beds"], lower and upper Oriskany: Trilobite Mountain, Orange 

County, N.Y. 

1905. Chonostrophia complanata. · Shimer, idem, pp. 189, 263. 

Upper Oriskany: 1 Trilobite Mountain, Orange County, N.Y. 

1905. Chonetes (Chonostrophia) complanata. Harris, Guide to the geology of Union Springs, p. 4, pl. 12, fig. 4. 

Oriskany sandstone: Yawger's Woods, Union Springs, N.Y. 

A couple of internal molds of pedicle valves from the Moose River sandstone of Somerset 

County, Maine, are referred to this characteristic species. The specimens show the pedicle 

valve slightly concave except over 'the muscular area and beak, where it is slightly convex. 

Over the center of this convex area there is an internal median septum extending about half 

the length of the shell, and on each side there is an obscure ridge (an impressed line in the 

i~ternal mold) ·extending forward from the teeth, which are very strong and sharp. The 

.cardinal area is of low or medium height, inclined at an acute angle. The bases of three or 

four spines are preserved along the hinge on one side of the middle. There are traces of very 

fine radial lines on the surface, but the molds are for the most part smooth. Length 8.5 

millimeters; width 13 millimeters. 

Locality: Moose River sandstone, Detroit; Somerset Qounty, Maine (locality 1100 A). 

U.S. National Museum, catalogue No. 59711. · 

Oomparisons.-The species called Chonetes dawsoni Billings is apparently the same form 

as 0. complanata Hall, as Clarke 2 pointed out; at least no reliable distinctio:n has been observed. 

The ventral valve varies from convex on the umbonal and visceral regions, and faintly concave 

in front to flat on the visceral region and strongly concave in front. The radial lines are also 

variable but are always fine, though not so fine and uniform as in Ohonostrophia helderbergia 

Hall and Clarke. In Ohonostrophia complanata Hall, as recorded by Clarke from Becraft 

Mountain, N.Y., in Ohonostrophia dawsoni Billings, and in the Maine form the median septum 

extends only about half the length of the valve. In Hall's typical 0. complanata, from the Oriskany 

sandstone (quartzite) of $choharie and Albany counties, and in the same form from the coarse 

sands of the Oriskany in Yawger's Woods, at the head of Cayuga Lake, N.Y., the septum is 

frequently as much as two-thirds the length. These shells from the sandstones are larger than 

the others and their sides are more nearly parallel, but it is believed that these are not constant 

distinctions. 

Ohonostrophia iervensis Schuchert, from the Dalmanites dentatus zone, 3 near Port Jervis, 

N.Y., is apparently only a small or young form of Ohonostrophia complanata Hall or 0. dawsoni 

Billings. Another Chonostrophia, 0. montrealensis, described by Schuchert/ has between 

the coarser lines one,' two, or three finer threadlike lines; the species· is small and strongly 

resupinate. It is reported from the upper (Helderbergian) fauna at St. Helens Island, near 

Montreal. The only remaining species of Chonostrophia, 0. reversa Whitfield (the type of the 

genus), is from the "Corniferous" limestone of Ohio and is a small reversed Chonetes having 

several fine radial lines grouped between each pair of coar:se lines. The finer lines are closer and 

more numerous than in 0. montrealensis Schuchert, which otherwise bears a very close relationship to Whitfield's species. The form of Ohonostrophia reversa found at Union Springs, N. Y., 

1 On p. 263 given also from upper New Scotland and lower Oriskany, evidently in error for C.jervisensis. 

2 Clarke, J. M., New York State Mus. Mem., vol. 3, No.3, p. 50, pl. 7, figs. 7-13, 1900~ 

a Schuchert, Charles, Am. Geologist, vol. 28, p. 250, figs. c, d, 1901. This horizon is at the top of the Port Ewen limestone or base of the 

Oriskany, and is included by some authors in the Helderberg and by others in 'the Oriskany. 

4 Idem, p. 250, figs. a, b. 
MOLL USCOIDEA. 57 

in the Onondaga ("Corniferous") limestone, is slightly different from the typical form of the 

species as it occurs in Ohio. In the Ohio specimen, as figured by Hall and Clarke, fine radial 

lines lie between the coarser ones, but in this respect the specimens from Union Springs approach 

Schuchert's 0. montrealensis. Chonetes manitobiensis Whiteaves has been mentioned as having a 

convex brachial'valve and a compressed pedicle valve and 1nay possibly prove to be an additional 

species of Chonostrophia. Before leaving the Chonostr'ophias attention ·must be called to the 

01·this tenuis of Monis and Sharpe, from the Falkland Islands, described in 1846. The original 

description 1 is as follows: "Nearly semicircular; both valves flat and covered with fine bifurcating strire, increasing to about 200 at the margin and crossed by a few concentric lines. Hinge 

aren. of the width of the shell, linear. The cast is scarcely thicker than a sheet of paper and 

faintly n1arke~ by the strire. Width 1! inches, length seven-eighths of an inch. Nearly allied 

to the Orthis expansa and 0. grandis of the Lower Silurian rocks." This shell is apparently 

chonetoid, though nC? spines have been observed on it. The typical forms indicate a shell of 

the appearance of Ohonostrophia dawsoni Billings or 0. complanata Hall. Strophomena expansa 

Sowerby, one of the two shells with which Orthis tenuis was compared, is perplanoid, and the 

similar form, 'Strophomena grandis Sowerby, is distinctly resupinate. It is therefore probable 

that the species is resupinate, in which case it might be referred to Chonostrophia. Schuchert 2 

regards Orthis tenuis as similar to Ohonostrophia complanata Hall. It should be borne in mind, 

however, that no indication of spines in Orthis tenuis has yet· been recorded. If spines are 

discovered in this species it will have to be referred to Chonostrophia and the name Ohonost?··ophia tenuis will have priority over 0. dawsoni and 0. complanata. 

Family ORTHID.tE Woodward. 

Genus DAL:MANELLA Hall and Clarke. 

DALMAN ELLA PLANOCONVEXA · (Hall). 

Plate VI, figure 17; Plate VII, figures 10, 11, 13, 14, 16-18, 20-22, 24-30. 

1859. Ortl~is JJlanoconvcxa. Hall, Paleontology of New York, vql. 3, p. 168, pl. 12, figs. 1-G. 

Lower Helderberg shaly limestone [New Scotland]: Albany County, N. Y.; Cumberland, Md. 

Oriskany: Cumberland, :M:d. · 

1874. Orthis lucia. Billings, Paleozoic fossils, vol. 2, pt. 1, p. 35, pl. 3, :fig. 4. 

Gaspe limestone No. 8 '[Grande Greve limestone]: Indian Cove, Gaspe Bay, Quebec. 

1876. Orthis planoconvexa. Barrett, Lyceum Nat. Hist. New York City Annals, vol. 11, p. 296. 

"Trilobite beds": Bennett's quarry, P<:>rt Jervis, N. Y. 

1882. Orthis planoconvexa. White, Pennsylvania Second Geol. Survey Rept. G6, p. 132. ' 

Uppermost Stormville shales ["Trilobite beds"]: Eastern Pike and Monroe counties, Pa., and William Nearpass 

quarry section in New Jersey. 

1883. Orthis lucia. Ells, Cana<;la Geol. Survey Rept. Progress for 1880-i882, p. 13DD. 

Gnspe upper limestones (Oriskan;y): Indian Cove, Grande Greve, and Little Gaspe, Gaspe Bay, Quebec. 

1889. Ortkis planoconvexa. Schuchert, New York State Geologist Eighth Ann. Rept., p. 52. 

Oriskany: Cumberland, Md. 

1892. Dalmanella JJlanoconvexa. Hall and Clarke, Paleontology of New York, vol. 8, pt. 1, pp. 207, 224. 

Lower Helderberg (no localities gi.Yen). 

1892. Rhipidomella l-ucia. Hall and Clarke, idem, p. 225. 

Devonian (no locality given). 

1897. Dalrnanella planiconvexa. Schuchert, U. S. Geol. Survey BulL 87, p. 202. 

Lower :Helderberg o.nd Oriskany: Albany County, N. Y.; Cumberland, Md. 

1897. Rhipidomella l·ucia. Schuchert, idem, p. 349. 

Oriskany: Indian Cove, Gaspe, Quebec. 

1899. Orthis (Dalm.anella) planoconvexa. Prosser, New York State Geologist Seventeenth Ann. Rept. (for 1897), 

pp. 340, 350. 

New Scotland shaly limestone: Countryman Hill and near Clarksville (Oniskethau Creek), Albany County, N.Y. 

?Becraft limestone: Onisket;hau Creek. 

1 Ocol. Soc. London Quart. Jour. 1 voL 2, p. 275, pl. 11, fig. 4, 1846. 

2 Schuchart, Charles, A synopsis of American fossil Brachiopoda: U.S. Ocol. Survey Bull. 87, p. 293, 1897. 
58 FAUNA OF THE CHAPMAN SANDSTONE OF MAINE. 

1900. Orthis (Dalmanella) planiconvexa. Schuchert, Geol. Soc. America Bull., vol. 11, pp. 282, 306, 314. 

New Scotland-Becraft: New York-Maryland-Virginia district; ?Tennessee. 

"Trilobite beds" (Becraft): Trilobite Ridge, near Port Jervis, N.Y. 

Monterey sandstone (Oriskany): Cumberland~ Md. 

1900. Orthis (Dalmanella?) lucia. Schuchert, idem, p. 329. 

Gaspe limestone No.8: Quebec. 

1900. Dalmanella planoconvexa. Clarke, New York State Mus. Mem., vol. 3, No.3, p. 73. 

Kingston (Port Ewen) shaly limestone: West Shore Railroad near Kingston, N. Y., one-half mile southeast of . 

Rondout Creek. 

1901. Orthis (Dalmanella) planoconvexa. Prosser, New York State Geologist Eighteenth Annual Rept. (for 1898), 

pp. 58, 61. 

New Scotland shaly limestone: High Point, Altamont, Knox, Helderberg Mountains, Albany County, N.Y. 

1903. Dalmanella .planoconvexa. Van Ingen and Clark, New York State Mus. Bul}. 69, pp. 1203, 1~06. 

Upper Port Ewen beds: Near Rondout, N. Y. 

· Oriskany: Glenerie, N. Y. 

1905. Dalmanella lucia. Clarke, New York State Mus. Bull. 80, p. 144. 

Grande Greve limestones: North shore of Gaspe Bay, Quebec. 

1905. Dalmanella planiconvexa. Williams and Kindle, U. S. Geol. s·urvey Bull. 244, p. 47. . 

Coarse sandstone (Lower Helderberg): East fork of Powell River (above the flouring mill; station 1376 A2, p. 28); 

and Southern Railway near Big Stone Gap (station 1376 B2, p. 28); Bland County, Va. 

Coarse sandstone (Oriskany): Rear of Alabama Row, White Sulphur Springs, W.Va. (1380 A2 , p. 34); Jackson 

River below Covington, Alleghany County, Va. (1382 B2 , p. 39). 

1907. Dalmanella' drevermanni. Clarke, New York State Mus. Bull. 107, p. 286 (pars) not fig. 

Lower Devonic [Chapman sandstone]: Edmunds Hill, Chapman Plantation, Aroostook County, Maine. 

Orthids of medium to. small size, convexo-planoid; radial lines 'fasciculate. Outline circular or subcircular; ratio of length to width commonly 8: 9; varying from 4:5 to nearly equal, 

greatest width at or just back of the middle. Hinge line very short; cardinal outline sometimes slightly concave each side of the beak. The pedicle valve is gibbous over the umbones as 

far as the middle, sloping to the front and sides; beak curved inward. Teeth supported by 

dental lamellre which curve around and include ·the musculature. Musculature half the 

length of the shell or a little more, indistinctly limited in front; ovoid in outline, widest near 

the middle. It is comn1only about twice as long as wide, with a low, blunt ridge extending 

down the middle. The musculature of the pedicle valve is somewhat similar to that of Schizophoria (cf. S. impressa or S. multistriata). The internal mold of the shell is mainly smooth 

except for some obscure radial vascular markings and a narrow striate fringe at the. margin. 

The brachial valve is nearly or quite flat and is commonly marked by a broad, faint, undefined sinus. On the interior the muscular impression is quadrate or subcircular, indistinct in 

front, and limited posteriorly by the thick cardinal process and by two short diverging ridges 

(the crural processes~). A low broad median ridge divides the musculature. This ridge is highest 

and widest at the posterior edge of the musculature and is continued anteriorly into a faint, low 

rounded ridge which extends nearly to the front margin, where it is commonly obscure. Posteriorly this ridge becomes more prominent and merges into the cardinal process; Cardinal 

process bluntly toothlike; in the Maine forms it is divided into two parts by a sharp, narrow 

impressed line on the inner side. In internal molds the cardinal process leaves a prominent 

. oval hole at the apex of the' valve. The internal mold is unornamented except by a narrow 

striate fringe about the margin. The surface of the shell is covered with coarse threadlike 

radial lines which increase by bifuroation and i;mplantation and are distinctly though uot very 

conspicuously fasciculate. In well-preserved specimens these lines are crossed by very obscure 

concentric lines of growth. The radial lines curve strongly upward near the posterior margin. 

It is extremely difficult to count the number of radial lines accurately, owing to the constant 

addition of finer ones alongside the coarser. The shell' structure is minutely punctate. Some 

of the punctre are arranged in distinct radial rows, but in other parts of the shell they are conlpactly crowded. The species may be recognized by its planoconvexity, very .convex pedicle 

valve, thick shell, fasciculate coarse radial lines, and very low cardinal area. The radial lines 

are finer and more numerous than in the Ordovician Dalmanella testudinaria, which the species 

ot4erwise closefy resembles. 

. .,. ' 
MOLL USCOIDEA. 59 

Locality: Chapman sandstone, west side of Edmunds Hill (very common), Edmunds Hill 

(occasional), Chapman Township, Aroostook County, Maine. · 

U.S. National Museum, catalogue Nos. 59712, 59713. 

Remarks on Dalmanella planoconvexa.-This species occurs in l;>oth the Helderberg and the 

Oriskany fauna. In the higher fannas of St. Helens Island, near Montreal, occurs an Orthis. 

which Schuchert regarded as '' 1nuch like the Oriskanian variety of D. zJlanoconvexa.'' This would 

imply that the I-Ielderberg and Oriskany representatives of this species are varietally distinct, 

but no such distinction has been en1phasized or even noted elsewhere in previous literature on 

the species. 

A very closely allied "species" fron1 the Grande Greve limestone of Indian Cove, Gaspe, 

is the Orthis lucia of Billings. This form differs from D. planoconvexa (I-Iall) in having no cardinal area, and it is possibly the Oriskany variety of. Hall's species referred to by Schuchert. The 

cardinal area of Dalmanella planoconvexa is extremely narrow-; it is observable only in the betterpreserved specimens f1~01n Maryland and New York and can not be seen in the :Maine specimens. 

As an Orthis with no cardinal area wp.atever would be anomalous, we are inclined to think that 

the shells of Orthis lucia of Billings; like those from Maine here described, represent a condition 

of preservation of D.zJlanoconvexa (Hall), in which the very narrow car~inal area of Hall's species, 

observable at best only in superlatively preserved specimens, is hardly discernible, and that 

Billings's specific nan1e has probably no. standing, even as the name of a variety. Hall and 

Clarke and Schuchert evidently tegard 0. lucia Billings as not only specifically but also generically dis. tinct from D. zJlanoconvexa, for they refer Billings's species to the genus Rhipidomella. 

The only basis for this reference is the assumption that the gibbous valve described by Billings 

is the ventral valve; but this is a doubtful assumption, and the :Maine material, which appears 

to correspond with Billings's descriptions, is a Dalmanella, not a Rhipidomella. 

Specific and stratigrazJhic relations.-In European Silurian-Devonian faunas Orthis orbiculwris Sowerby, fron1 the Ludlow beds of England, Ireland, and Esthonia,t has been regarded as 

a close ally of D. planoconvexa, but this European shell is a distinct form, having the brachial 

vuJve nwre convex and the musculature shorter t;h.an in the American forms, and Sowerby's 

types also lack the fasciculation of the radirtllines. 

In the Devonian of Turkey, Germany, northwestern France, and Spain 2 there occurs an 

Orth!s which is with difficulty distinguishable fro1n D. planoconvexa I-Iall. This European species 

was originally identified by De Verneuil 3 with Sowerby's · Orthis orbicularis. Subsequently it 

was discovered that Sowerby's species was different, but as the English form has been regarded 

by son1e as a variety of 0. elegantula, which it really is not, De Verneuil decided to retain the 

name 0. orbicularis for the Lower Devonian continental species. This decision has been adopted 

by Kayser and others. In this European shell the pedicle valve appears to be more ventricose 

tlum in the An1erican species, and is less subcarinate and n1ore broadly inflated. 

DALl\fANELLA d. D. CIRCULARIS Sowerby. 

Plate VII, figure 9. 

The following synonymy inolu~·es some of the more important references to Sowerby's 

species: 

1842. Orthis circularis. Sowerby, Geol. Soc. London Trans., 2d ser., vol. 6, p. 409, pl. 38, fig. 12. 

Hhenish Lower Devonian: Daun, in the Eifel, Germany. 

1845. Orthis orbicttlaris (not Sowerby). De Verneuil, Soc. geol. France Bull., 2d ser., vol. 2, p. 478, pl. 15, fig. 9. 

Eo-Devonian limestone: Ferrones and Pelapaya, Asturias, Spain. 

1853. Orthis circularis. Schnur, Palaeontographica, vol. 3, p. 218, pl. 39, fig. 1 (?pl. 38, figs. 5a, 5b). 

Graywacke (Lower Coblenzian): Daun and Daleiden, in the Eifel, Germany. 

I Soo Orthis lunata in Davidson, Thomas, Monograph of British fossil Brachiopoda, pt. 7, Silurian, p. 215, pl. 28, figs. 1-5, 1870. 

s Soo Orthis orbicularis in Kayser, li:manuel, Die Fauna der.ii.ltesten Devon-Ablagerungen des Harzes: Abh. Geol. SpeCialkarte Preuss., etc., 

Bd. 2, Heft 4, 1878, p. 187, pl. 28, figs. 11-13; pl. 34, fig. 7. 

u Soc. gool. France Bull., 2d sor., vol. 2, p.'81, pl. 15, fig.'9, 1845. 
60 FA UN A OE THE CHAPMAN SANDSTONE OF MAINE. 

1854. Leptmna orbicularis(?). Wirtgen, 1 Naturhist. Ver. preuss. RheinHinde Verh., vol. 11, p. 374. 

Lowest graywacke [Taunusian?J Bonsbeuren, near Bertrich, Rhenish Prussia. 

1857. Orthis circularis. Krantz, idem, vol. 14, p. 155. 

[Eo-]Devonian: Menzenberg, Daun, and Daleiden, Prussia. 

1871. Orthis.circularis. Kayser, Deutsch. geol. Gesell. Zeitschr., vol. 23, p. 603, footnote. 

[Lower Eo-]Devonian: Daun and Stadtfeld, in the Eifel, Germany; Ferrones and vicinity, Asturias, Spain; 

Nehou, La Manche, France. 

1871. Orthis circularis. Quenstedt, Petrefakten Deutschlands, Brachiopoden, pp. 569, 573, pl. 56, figs. 8, 9, 13, 14 (not 

20-22). . 

Graywacke [Lower Coblenzian]: Daun, Daleiden, Laubach, Kemmenau, Germany. 

1876. Orthis circularis. Ribbentrop, Naturhist. Ver. preuss. RheinHinde Corr.-Bl., vol. 33, p. 103. 

Taunusian to Hundsruckian.[Eo-Devonian]: Between Nerother Head, Oberstadtfeld, and Salm, in the Eifel, 

Germany. 

1881. Orthis cf. 0. cir~ularis. Kayser, K. preuss. Geol. Landesanstalt Jahrb. (for 1880), p. 263. 

Taunus quartzite: Sauerbrunnen and ?Neuhiitte, near Birkenfeld, Prussia. 

1881. Orthis circularis. Dewalque, Soc. geol. Belgique Bull., vol. 8, p. 159 .. 

Ahrien (L9wer Coblenzian): Niederstadtfeld, in the Eifel, Germany. 

1882. Orthis circularis. Follmann, Naturhist. Ver. preuss. RheinHinde Verh., vol. 39, pp. 153, 171, 178. 

Lower graywacke: Bonsbeuren, near Bertrich, Germany. . 

Upper graywacke, Chondrites beds, and higher: Near Olkenbach, southern Eifel, Germany. 

1883. Orthis aff. 0. arcuata. Kayser, K. preuss. geol. Landesanstalt Jahrb. (for 1882), p. 131. 

Taunusian: Saltern Railway cut, 4 to 5 miles south of Torquay, South Devonshire, England. 

1885. Orthis C'l:rcularis. Gosselet, Soc. geol. Nord Annales, vol. 13, pp. 334-338. 

Taunusian: Anor; woods of the Harscamp hospital back of Montigny-sur-Meuse; Virrus Woods, northeast of 

N ouzon; 148.56-kilometer pqst on the railroad near N ouzon; N eufmanil Woods; Grand Duchy of Luxembourg. 

1887. Orthis circularis. Bedard, Soc. beige geologie, paleontologie et hydrologie Bull., vol. 1, 1887, p. 871 pl. 4, figs. 

13, 14. 

Coblenzian [Taunusian]: St. Michel,. near St. Hu.bert, Belgium. 

1891. Orthis circularis. Follmann, Naturhist. Ver. preuss. RheinHinde Verh., vol. 45, p. 141. 

Lo·wer Spirifer sandstone (Lower Coblenzian): Vallendar, Ehrenbreitenstein, Pfaffendorf, Bienhornthal, Laubach-Konigbach. 

Middle Spirifer sandstone (Coblenz or Ems quartzite): Bi~nhornthal, Oberlahnstein (?), ·Muhlthal, and 

Konigsstuhl. 

Upper Spirifer sandstone (lower part of Chondrites beds): Vallendar Valley; all localities in the Coblenz district, 

Germany. 

1899. Orthis circularis. Collins, Roy. Geol. Soc. Cornwall Trans., vol. 12, pp. 233, 239. 

Siegen, or probably Lower Coblenzian: Fowey, Cornwall, England. 

1902. Orthis circularis. Drevermann, Palaeontographica, vol. 49, p. 109, pl. 14, figs. 1-3. 

Siegen graywacke: Seifen. 

Lower Coblenzian: Oberstadtfeld, near Daun, in the Eifel, Germany: 

1906. Orthis circularis. Green and Sherborn, Geol. Mag., dec. 5, vol. 3, p. 35. 

Taunusian: Polyne quarry, Cornwall, England. 

cf. 1907. Dalmanella drevermanni. Clarke, New York State Mus. Bull. 107, p. 286, fig .. 

Lower Devonic [Chapman sandstone]: Edmunds Hill, Chapman, Maine. 

1907. Orthis circular:is. Ussher, Geology of the country around Plymouth and· Liskeard, Devon-Cornwall (Geol. Survey 

England and Wales, Explan. Sheet 348), p. 33. 

Meadfoot group shales [Taunusian]: Quarry north of Polyne farm, Looe district, Cornwall, England. 

1909. Orthis circularis. Usshe.r and others, Geology of the country around Bodmin and St. Austell, Cornwall (idem, 

sheet 347), p. 25. 

Meatfoot group [Lower Coblenzian]: Fowey, Cornwall, England. 

A small brachial valve found in the Chapman sandstone at Edmunds Hill closely resembles 

the species from the Rhenish Lower Devonian described by Sowerby under the name Orthis 

circularis. The close similarity of the species to Dalmanella planoconvexa Hall was observed 

by Drevermann. Clarke apparently refers to the same species, as well as to Dalmanella planoconvexa, in applying the new name Dalmanella drevermanni to Chapman sandstone specimens 

from the same locality as the present material. The dorsal valve figured by Clarke and described as D. drevermanni appears to be the same species as our Dalmanella cf. D. circularis 

Sower by. 

1 Wirtgen's material, in the museum of the Prussian Rheinland Natural History Society, is identified with Sower by's species by Follmann, 1882. 

' 

,· 
~ 

,, 

... 

MOLL USCOIDEA. 61 

The shell is subcirculo.r in outline; length 10.5 millimeters, width 11.5 millimeters, greatest 

width just above the n1iddle. The dorsal valve is nearly flat, depressed convex without evident 

sinus; 1narked by strong dichotomous radial lines which are not fasciculate. A few fragments of 

the pedicle valve also show distinctly nonfasciculate radial sculpture; in curvature and in internal structure they agree with D. planoconvexa. As for internal structure, Drevermann's figures 

of D. circ'l.llaris and the figures of D. planoconvexa in the present work might have been made 

fr01n the same specimens. 

Most of the ~pecimens o~ Dalmanella of this general type from the Edmunds Hill locality 

we have identified with D: planoconvexa (IIall). The shells referred to Sowerby's species differ 

from D. planoconvexa in lacking the dorsal ~inus and in having the radial lines nonfasciculate 

though strongly dichotomizing. 

Locality: Chapman sandstone, west side of Edmunds Hill, Chapman township, Aroostook 

County, Maine. ' 

U. S. National Museum, catalogue No. 59714. 

Genera SCENIDIUM Hall and MYSTROPHORA Kayser. 

The genus Skenidium (now spelled Scenidium)1 was founded by Hall 2 in the year 1860 to 

include orthqid shells having a wide hinge line with angular extremities, a high cardinal area in 

the convex pedicle valve, and a fairly well developed though lower area in the depressed brachial 

valve, and on the interior of the brachial valve a thick median septum. The septum extends 

in smne forms the entire length of the valve and downward as far as the pedicle valve; in the 

l.'nnbonal region a ~poonlike bowl on each side is formed by a ridge or septum curving round from 

near the base of the crura to the median septum. The structure is somewhat similar to the 

spondylium of the pentameroids but differs in several respects, chief an1ong which is that in 

Scenidiun1 the median septum is continued through this pseudospO'ndylium to the tip of the beak, 

fonning "spondylia" on each side of the median septum, whereas 'in the superficially similar 

Clitnn1bonites nnd in nil the true pentameroids the spondylium is simple and the septum when 

present extends only to the front edge of the simple spoon and not to the tip. of the beak. In 

Scenidium there are also in the pedicl~ valve no such septal struct~res as are usually developed 

in the pentameroids. The genus Scenidium is rather well marked interiorly and of typical low, 

Cyrtina-like aspect on the exterior. 

In 1871 Kayser,3 apparently unaware of Ifall's.genus Scenidium, erected the genus l\1ystrophora for sn1alllow Cyttina-like orthids with the same internal structure as Scenidium-a small 

n1edian septun1 in the depressed brachial valve and a spoonlike bowl on each side in the umbonal 

region, with the cardinn.l process weakly developed. The type of Mystrophora was Quenstedt's 

Orthis areola, fron1 the Eifelian, Middle Devonian, and Kayser included in his genus also Orthis 

lewisi Davidson/ fr01n the Wenlock of Great Britain and Gotland. 

I-Iall and Clarke 5 in 1892 regarded Mystrophora as a complete synonym of Scenidium. They 

noted not a single point of distinction between Mystrophora and Scenidium and since then Scenidium has been supposed to include Mystrophora. Winchell and Schuchert remove these shells 

altoge~her fron1 the ort.hids and place them near Clitambonites in the group of Pentameracere, 

presun1a~ly because of the presence of the pseudospondylium and the superficial resemblance to 

Clitambonites, which is commonly regarded as ·pentamenerid. 

The genus ~1ystrophora is not, however, identical with Scenidium, for whereas all the Ordovician. and Silurian species of Scenidium have impunctate shells, Orthis (Mystrophora) areola 

is strongly punctate. Kayser 6 in his description of Quenstedt's species 0. (M.) areola says: 

"Schalenstrucktur perforirt," and he figures the punctate shell structure. In Mystrophora the 

delthyriun1 is entirely open, not partly' closed as in several species of Scenidium. The surface 

'Oehlert, D.P., Soc. etudes sci. Angers Bull.,1887 (p. 4 of separate). Hall and Clarke, Paleontology of New York, pt.1, p. 241, 1892. Winchell 

and Schuchert, Minnesota Gcol. Survey, vol. 3, p. 381, 1893. 

l1 New York State Cab. Nat. Bist. 'l'hirteenth Ann. Rept., p. 70, figs. 1-5, 1860; type Orthis insigne Hall, Lower Helderberg. 

s Kayser, Emanuel, Die Bmchiopoden des mittel und ober Devon der Eifel: Deutsch. geol. Gesell. Zeitschr., 1871, p. 612, pl. 13, fig. 5. 

• Davidson, Thomas, British Silurian Brachiopoda, p. 208, pl. 26, figs. 4-9, 1869. 

a Op. cit. · 

a Op. cit., p. 612, middle of page, pl. 13, fig. 5i. 
62 FAUNA OF THE CHAPMAN SANDSTONE OF MAINE. 

is finely or coarsely ribbed, with the riblets increasing by bifurcation or frequent implantation, 

as distinguished from the simple plications on the surface of typical Scenidium. 

Mystrophora does not. belong in the family Pentameridre, for not only is its spondylium-like 

structure· entirely distinct fr'om that of the pentamerids, but the shell structure is punctate and 

the muscular scars ~re strongly impressed and occupy the bottom of the valve. :Mystrophora 

and the closely allied but distinct genus Scenidium Hall should therefore be retained among the 

orthids, where they were originally placed by Hall, Davidson, Kayser, Oehlert, and Clarke. 

In specimens of Mystrophora elevata from Maine the spoonlike bowls each side of the median 

septum are d,istinctly preserved in the internal mold, but they do not appear to. be so well developed as in the typical forms of Scenidium and Mystrophora. The median septum, too, though 

well developed, thick, and deep, does not attain the extreme development observable in these 

genera. It is possible that more and better material may show less de.viation from the typical 

Mystrophora, but our specimens, even as they are, may safely be referred to Kayser's genus. 

The shell structure is punctate. The species closely resembles Dalmanella, with which it was 

originally identified, and serves to show the very close relationship between Mystrophora and 

Dalmanella. Scenidium devonicum Walcott 1 from the Lower· Devonian of Nevada is placed in 

the genus Dalmanella by Schuchert,2 but should probably be included in !1ystrophora. It is also 

probable that a closer study will tend to remove several other doubtful species now referred to 

the impunctate genus Scenidium and some cyrtinaform Dalmanellas into the punctate genus 

Mystrophora. 

The name Mystrophorus was used by Forst in 1856 for a genus of Hymenoptera prior to 

Kayser's proposal of the name Mystrophora in 1871. This should not, however, invalidate 

Mystrophora. 

DALMANELLA (MYSTROPHORA) ELEVATA sp. nov. 

PlateVI, figures 1, 2·, 3, 6, 9; Plate VII, figures 12, 19, 23; Plate VIII, figures 17-23. 

The pedicle valve is elongate, semielliptical, with a broad, straight hinge line, rather sharp 

cardinal extren1ities, and obtusely acuminate umbo. The valve is suhcarinately gibbous. 

The greatest height)s equal to one-third the length and is situated over the beak, from which 

the surface slopes to the front and lateral margins. The tip of the beak is hardly at all incurved. 

The cardinal area of the pedicle valve is very high, almost equal to the height of the valve. It 

is only slightly arching and is inclined at an angle of 60° to the plane of the margin. Delthyrium open; ·angle 45° or less. The musculature of the pedfcle valve is pentagonal-cordate in 

outline. It extends forward to the middle of the shell, or slightly beyond, and is surrounded 

by a raised ridge o.r platform. It is divided into two elongately trigonal scars, which are not 

subdivided. Surface of the pedicle valve unknown, but.marked, apparently, by rather coarse 

radial lines. 

The brachial valves, which are regarded as belonging to this species, are quadrately subcircular. The hinge· line is broad and straight and is about two-thirds the width of the shell. 

The posterior margin. reclines from the beak at an angle of 145° to 150°. The cardinal extremities, if preserved, are sharp and obtusely angular. The proportion of length to width of the 

brachial valve varies from 6 : 7 to 7 : 9; the greatest width is at or slightly "in front of the 

middle. The cardinal area extends the width of the hinge line, or about two-thirds the width 

of the shell, and is well developed, though less conspicuous than that of the opposite. valve. 

The brachial valve as a whole is depressed convex; a specimen 13 millimeters long and 14.5 millimeters wide has a depth of 1.25 millimeters. The valve is n1arked by a distinct rounded sinus 

of undefined li1nits. On the interior of the brachial valve the thick crural bases extend in 

front of the deep dental sockets. A thick median septum reaches one-third the length of the 

valve and ends posteriorly in the cardinal process, which appears to have been sin1ple and to 

have had an impressed line down its center. In front of the median septum there is on each 

side a large, circular, indistinctly bipartite adductor scar extending a trifle in advance of the 

1 ·walcott, C. D., Paleontology of the Eureka district [Nevada]: U.S. Geol. Survey Mon. 8, 1884, p. 116, pl. 13, fig. 4. 

2 Schuchert, Charles, Synopsis of American fossil Bracpiopoda: U.S. Geol. Survey Bull. 87, p. 200, 1897. 
MOLL USCOIDEA. 63 

Jnidlength of the valve. Behind this muscular scar there is on each side, in the internal1nold, 

a troughlike depression curvirig around from the base of the crura to the median sep tu1n. 

This represented, in the original shell, a low, curving ridge which inclosed a· spoonlike basin 

in the mnbonal region on each side of the median septum, as in Scenidium and Mystrophora, 

but apparently not quite so well developed as in typical forms of those genera. The shell is 

coarsely punctate; the punctre are closely crowded and do not appear to be arranged in any 

rndial, concentric, quiilCunx, or other regular order. 

'I'he ornamentation on the brachial valve consists of very coarse, nonfasciculate, radial 

lines or ·riblets, which .increase by bifurcation, rarely by in1plantation. These are crossed in 

the best-preserved specimens by concentric lines which are weakly developed on the crests of 

the radinl lines, but which impart to the interspaces a strongly crenulate aspect. About 50 

rn.clial riblets or lines may be counted at the margi~ of an average specimen. 

The distinguishing features of the species 1are the high cardinal area in both pedicle and 

brachial valves, the wide hinge line and subangular cardinal extremities, the coarse surface 

lines or riblets, the depressed convex brachial valve with broad undefined sinus, and, on the 

interior, it large spondylium with the median septum continumg through it ~nd dividing it 

in two. 

Locality: Ed1nunds IIill (locality 1099 02), Chap1nan Township, Aroostook County, Maine. 

U.S. National Museum, catalogue No. 59715. 

Oomp(trisons.-This species resembles Scenidium devonicum Walcctt 1 in the outline and 

convexity of the pedicle valve, but that species is a minute form, much smaller than our 

species, and has coarser ornamentation. The wide, straight hinge line and elongate outline 

recall n.lso Orthis (Rhipidomella) eminens Hall,2 but that fossil has the musculature of RhipidOJnella, and its pedicle valve is more depressed than in Dr;tlmanella elevata. 

Orthostrophia canadensis Clarke 3 bears a close resemblance to our Daimanella (Mystrophora) 

elevata, but it has a much smaller musculature in both valves, and the fold or carination in 

the pedicle valve is much better developed than in the Chapman fossil. 

D([,lmanella penouile Clarke, 4 from the so-called Middle Devonian of the Gaspe basin, 

Quebec, has a wide posterior margin and high cardinal area, like the Chapman fossils under 

consideration, and the outline and ornamentation are approximately similar in the two, but 

the Gaspe forn1 is described as having a short hinge line. . I 

Order TELOTREMATA Beecher. 

Family RHYNCHONELLIDJE Gray. 

Genus STENOSCISMA Conrad (CAMAROT<ECHIA of authors, in part). 

The species Stenoscisma .formosa I-Iall is the genotype of the genus Stenoscisma of Conrad, 

1839,5 and of I-Iall, 1867. 0 The discovery, in the Chapman specimens of the species, of dental 

plates in the pedicle valve, and of a forked or Y -shaped septum in the brachial valve, together 

with the absence of a cardinal process, shows that they are identical with the n1ass of Paleozoic 

rhynchonelloids referred by authors to the genus Camarotmchia Hall and Clarke. 7 The genotype of Camarotmchia, 0. congregat([, (Conrad), displays crenulated or corrugated dental sockets, 

which are also observable in a few other species, chiefly fron1 the Middle and Upper Devonian 

( 0. contr([,cta (I-I all), 0. eximia (Hall), 0. orbicularis (Ha.ll), 0. prolijica (I-I all), Rhynchonella 

alleg([,nia (Williams), etc.). This character has not yet been observed in the Maine speci1 Walcott, C. D., U.S. Geol. Survey Mon. 8, p. 116, pl. 13, fig. 4, 1884; Lower Devonian, Eureka district, Nev. 

~Sec Schuchcrt, Charles, U.S. Geol. Survey Bull. 87, p. 348, 1897, for references to this species. It is de~ribed from the New Scotland lime 

stone of tho Helderberg group in New York and is reported from the Helderbergian Square Lake limestone of Square Lake, Maino, as well as rrom tho limestone containing Becraft; fossils at St. Helens Island, near Montreal, Canada. 8 N cw York State l\Ius. Bull. 107, p. 285, figs., 1907. The species is described from the St. Albans beds of the Grund Cove and Cape Rosier Cove, 

Quebec, and reported from Square Lake, M:aine. 

• Idem, pp. 285-286, figs. 

~Now York Goo!. Survey 'l'hird Ann. Rept., pp. 58, 59, 1839. 

OPnlcontology of New York, vol. 4, pp. 334,335,1867. 

1 Idem, vol. 8, pt. 2, p'. 189, 1893. 
64 FAUNA OF THE CHAPMAN SANDSTONE OF MAINE. 

mens of Stenoscisma formosa, nor indeed in the bulk of species referred to Camarotrechia. If 

it should really prove to be absen:t in Stenoscisma, then Camarotrechia may stand as a valid 

genus distinguishable from Stenoscisma in that it has the dental sockets crenulated. 

Owing to the uncertainty previously attendant upon the use of the name Stenoscisma of 

Conrad, Schuchert 1 has proposed· that Stenoscisma be abandoned altogether and has referred 

S. formosa to the genus Rhynchotrema Hall, 1860. In Rhynchotrema, however, there is a 

cardinal process present throughout life,2 and the genus also lacks dental lamellre. Nearly a 

dozen species ,known to belong to Rhynchotrema are exclusively Ordovician. I am therefore . 

of the opinion that the generic name Stenoscisma is appropriately applied to the species described 

by Hall as its type species and here follow the usage proposed by Hall and Clarke in 1893. 3 

STENOSCISMA FORMOSA Hall. 

Plate VI, figures 4, 5, 7, 10, 14, 21, 22, 25, 26. 

1839. Stenoscisma='' Terebratula schlotheimii (von B uch ). '' Conrad, New York Geol. Survey Third Ann. Rept., pp. 58-59. 

See Paleontolvgy of New Yor.k, vol. 8, pt. 2, p. 187. 

"Silurian:"- New York. 

1857. Rhynchonellaformosa. Hall, New York State Cab. Nat. Hist. Tenth Ann. Rept., p. 76, figs. 1-5. 

Shaly limestone of the Lower Helderberg and in the Upper Pentamerus limestone: Albany and Schoharie 

counties, N.Y .. 

1859. Rhynchonellaformosa. Hall, Paleontology of New York, vol. 3, p·. 236, pl. 35, fig. 6. 

Shaly limestone of the Lower Helderberg group, and in the Upper Pentamerus limestone: Helderberg Mountains, Schoharie, Hudson, Catskill, Carlisle, Cherry Valley, and other places in New York. 

1867. Stenoscismaformosa. Hall, idem, vol. 4, p. 334. · 

Lower Helderberg: New York. 

1874. Rhynchonella dryope. Billings, Paleozoic fossils, vol. 2, ,pt. 1, p. 37, pl. 3, figs. la-c. 

Gaspe limestone No.8: Grande Greve,· Gaspe Bay, Quebec. 

1878. Rhynchonellaformosa. Ashburner, Pennsylvania Second Geol. Survey Rept. F, p. 241. 

Basal 50 feet of Lewistown limestone: Aughwick Valley, Huntingdon County, Pa. 

1881. Rhynchonella formosa. Platt, Pennsylvania Second Geol. Survey Rept. I, p. 41. · 

Lower 50 feet of Lewistown limestone: 'Huntingdon County, Pa. 

1883. Rhynchonella dryope. Ells, Canada Geol. Survey Rept. Progress for 1880-1882, p. 13DD. 

Upper Gaspe limestones (Oriskany): Indian Cove, Grande Greve, and Little Gaspe, Gaspe Bay. 

?1883. Rhynchonellaformosa. White, Pennsylvania Second Geol. Survey Rept. G7, pp. 89, 98, 101, 261, 311, 313. 

Bastard limestone: Mauser quarry, Montour Township, Columbia County, Pa. . 

Between Bastard and Stromatopora limestones: D. Derr's quarry, Limestone Ridge, Liberty Township, and 

A. F. Russell quarry, near Mahoning Creek, Valley Township, Montour County, Pa. 

Stromatopora limestone: Quarry opposite Lime Ridge station, Columbia County, Pa. 

1885. Rhynchonellaformosa. White, Pennsylvania Second Geol. Survey Rept. T3~ pp. 126, 172. 

Bastard limestone: Lincoln Township. 

Near base of Lewistown limestone: Aughwick Valley. Both localities in Huntingdon County, Pa. 

1886 .. Rhynchonellaformosa. Darton, Am. Jour. Sci., 3d ser., vol. 31, pp. 212, 214. 

Lower Helderberg: Cornwall station, Orange County, N. Y. 

not 1886. Rhynchonellaformosa. Shaler, Am. Jour. Sci., 3d ser., vol. 32, p. 55. 

Lower Helderberg siliceous limestone: Half a mile south of Balls Mills, Wl1iting Bay, Maine. 

1890. Rhynchonellaform"osa. Deeks, Canadian Rec. Sci., voi: 4, No. 2, p. 108. 

Lower Helderberg: St. Helens Island, Montreal. 

1893. Stenocismajormosa. Hall and Clarke, Paleontology of New York, vol. 8, pt. 2, p. 187, pl. 56, figs 41-45. 

Lower Helderberg group: Albany County, N. Y. 

1896. Rhynchonellaformosa. Ami, Canada Geol. Survey Ann. Rept., new ser., vol. 7, p. 156J. 

Lower Helderberg: St. Helens Island, Montreal. · 

?1897. Rhynchotremaformosum. Schuchert, U. S. Geol. Survey Bull. 87, p. 369. 

Lower Helderberg: Schoharie and Albany counties, N.Y.; Lake Temiscouata, New Brunswick; Arisaig, Nov,.. 

Scotia. 

1899. Stenochismajormosa. ~rosser, New York State Geologist Seventeenth Ann. Rept. (for 1897), pp. 340, 351. 

New Scotland shaly limestone: Countryman Hill and Oniskethau Creek sections, Albany County, N.Y. 

1900. Camarotcechia dryope. Clarke, New York State Mus. Mem., vol. 3, no. 3, p. 41, pl. 5, figs. 20, 21. 

Oriskany siliceous limestone: Becraft Mountain, Columbia County, N. Y. 

1 Schuchert, Charles, Synopsis of American fossil Brachiopoda: U.S. {.}eol. Survey Bull. 87, p. 413, 1897. 

2 Winchell, N.H., and Schuchert, Charles, Geol. and Nat. Hist. Survey Minnesota, vol. 3, pt. 1 (Paleontology), p. 458, 1895. 

a Hall, James, and Clarke, J. M., Paleontology of New York, vol. 8,·pt. 2, p. 187, 1893. 
lVIOLL USCOIDEA. 65 

1901. Stenochismafonnosa. Prosser, New York State Geologist Eighteenth Ann. Rept. (for 1898),· p. 61. 

New Scotland shaly limestone: Knox, Albany County, N. Y. 

?1903. Rhynchonella (Rhynchotrem.a)jonnosa. Schuchert, U. S. Nat. Mus. Proc., vol. 26, pp. 418-423. 

Manlius shaly limestone: Baltimore & Ohio Railroad quarries, Kayser, Mineral County, W. Va.; Devils Backbone, near Cumberland, Mel. 

1903. Rhynchotrernajonnoswn. Weller, Paleontology of New Jersey, vol. 3, pp. 92, 94, 95, 309, 328, pl. 36, figs. 5-12; 

pl. 42, figs. 5-8. · 

Becraft limestone: Near Nearpass quarry, N. J. 

"Trilobite beds:" Near Nearpass quarry and three-fourths of a mile southwest of Wallpack Center, N. J. 

1903. Rhynchotrernajormosurn. Van Ingen and Clark, New York State Mus. Bull. 69, pp. 1188, 11.91, 1193. 

Basal Coeymans limestone, upper New Scotland limestone, middle Becraft limestone: Becraft Mountain, Columbia County, N.Y. 

?:1.903. Rhynchotrernajorrnoswrn. Van Ingen and Clark, idem, p. 1203 (error for Rhynchospirajonnosa?). 

Oriskany siliceous limestone: Glenerie, N.Y. 

1905. Carnarot(J'.chia dryope. Clarke, New York State Mus. Bull. 80, p. 146. 

Grande Greve limestone: North shore of Gaspe Bay, Quebec. 

1905. Stenochismafonn:osa. Shimer, idem, pp. 185, 227, 245, 265. 

Upper New Scotland and "Trilobite beds" (lower Oriskany): Trilobite Ridge, Orange County, N.Y. 

1905. Rhynchotremajonnoswn. Williams and Kindle, U. S. Geol. Survey Bull. 244, p. 28. 

"Oriskany" sandy and cherty beds: Southern Railway, near Bigstone Gap, Wise County, Va. 

Biconvex, highly gibbous, subglobular rhynchonellids of medium size, with less than 24 

coarse ribs. Pe~icle valve ventricose, less so than the . brachial; beak strongly in curved at 

nearly right angles to the plane of the margin. In longitudinal profile the shell is flat for twothirds of the length of the front; surface elevated, abruptly deflected to the postero-lateral 

margins, less abruptly deflected in front. A mesial sinus is deeply depressed in front, flat at 

the bottom, but is obsolescent. ii1 the region over the musculature. The mesial profile of the 

sinus is evenly arcuate longitudinally. The musculature extenqs not quite half the length of 

the shell. It is elongate trigonal, strongly elevated in front, and surrounded by ·a border elevated above the interior surface of the valve. The adductor scars are oval or circular, sunken, 

rather sinall, and continued posteriorly into an elongate cicatrix (the pedicle muscular scar), 

which extends along the middle of the musculature to the posterior end. Small dentallan1ellre 

are distinctly preserved in the better specimens. These lamellre are short, bound the musculature posteriorly, diverge at an acute angle of about 55° to 70°, and in well-preserved internal 

n1olds leave a very thin, knifelike extension of the rock matrix projecting toward the beak. 

They are well developed in younger individuals but tend toward obsolescence at maturity. 

The delthyrial characters are obscure ·and uncertain. ,The delthyrium seems to have been an 

open fissure in the posterior margin with cardinal area entirely absent. The tip of the beak is 

invariably broken in the Maine specimens, but whether this indicates a circular pedicle opening 

at the apex or accidental fracture can not be definitely stated. 

'The brachial valve is broadly, rather uniformly, and very highly inflated, its depth being 

equal tq half the length or n1ore. There ~s a pronounced fold in front, where it is strongly 

raised above the general surface by the elevation of the outer slopes of' the outermost ribs 

(on the fold). The anterior 1nargin of the valve is insinuate in the region of the fold. On the 

interior of the brachial valve there is a distinct median septum which extends nearly a quarter 

the length of the shell. Its detailed features are not preserved, though it appears to fork posteriorly. The average size of the specimens is about 15 millimeters in length by about 15.5 

1nillimeters in width. 

The surface is covered by ·16 to 22 strong rounded ribs, becoming subangular in front. 

Three or four ribs are in the. sinus and four or five on the fold. ·They extend to the beak.' Most 

specimens have only six ribs on each side of the fold and sinus and thus agree very well. with 

the form . of Stenoscisma formosa from Gaspe, called RhynchoneBa dryope by Billings. This 

forn1 occurs at Becraft Mountain, according to Clarke, and according to Weller, in the New Scot-· 

land-Becraft beds and in the Dalmanites dentatus zone of New Jersey. Billings's species was 

supposed to differ from Stenoscisma formosa in having slightly stronger ribs, but in the forms 

50245°--~0.89--16----5 
66 ' FAUNA OF THE CHAPMAN SANDSTONE OF MAINE. 

here discussed this character possesses little or no diagnostic value, for it· is determined largely 

by conditions of preservation. 

Locality: Chapman sandstone, west side of Edmunds Hill, Chapman Township, Aroostook 

County, Maine. The recording of the form of the species known' as Stenoscisma dryope (Billings) 

from the Oriskany of New York and Quebec suggests that the fossil may be also expected in 

the· Moose River sandstone fauna of northern Maine. · 

U.S. National Museum, catalogue No. 59716. 

Oomparisons.-This species is referred by Schuchert to the genu~ Rhynchotrema and 

h~s therefore commonly come to be known among American geologists as Rhynchotrema formosum. In 1900, in discussing the evolution of the rhynchonelloids of the Maine Devonian, 

I suggested 1 then that this species probably could not belong to the genus Rhynchotrema. The 

genus Rhynchotrema (type species, Rhynchonella capax) j.ncludes the following species: 

Rhynchonella (Rhynchotrerna) capax (Conrad), Lorraine. 

inmq~ivalve (Oastelnau), Trenton. 

laticostatum Winchell and Schuchert, Trenton. 

ainsliei Winchell, Trenton. 

ottawaense (Billings), Trenton. 

perlamellosum Whitfield, Lorraine. 

subtrigonalis Hall, Trenton. 

dentatum Hall, Trenton and Lorraine . . .. 

None of the members of this group of species pass above the Ordovician in the geologic 

column, and the Rhynchonella formosum in the Helderberg is the only species referred to the 

genus above· the Ordovician. As I said in 1900, ''The genus is thus characteristically Ordovician in age, and the propriety of referring the Lower Helderberg species to the genus calls for· 

careful examination." The impropriety of Rhynchotrema as a generic receptacle for Stenoscisma formosa has already been referred to in the discussion of Conrad's' genus. 

STENOSCISMA FORM OS~ Hall (young). 

Plate VI, figures 25, 26. 

A small rhynchonelloid was found at Edmunds Hill in the same strata with the larger 

mature specimens of Stenoscisma formosa above described and is regarded as the. young of that 

species. The specimen, which is only 6.8 millimeters long, 6.8 millimeters wide, and 3.1 millimeters thick, preserves important internal characteristics which are less clearly defined on the 

larger specimens. 

Shell small, depressed, biconvex; outline trigonal, widest in front of the middle. Pedicle 

valve depresse~ convex, hardly appreciably less convex than the brachial valve; apex acuminate, subtending a right angle. A sinus is beginning to appear at the margin. This sinus 

is deeply excavated;. its bottom is flat and marked by three plications. On each side there 

are :five or· six plications. The brachial valve is strongly convex, ·but hardly appreciably 

more elevated than the pedicle valve. The outline is rounded, and the length is 0.9. millimeter 

less than that of the pedicle valve. On the surface a strongly elevated fold is. beginning to 

appear on the front margin, where there are four plications on the incipient fold and four or five 

more on each side. The plications are very strong and reach nearly to' the apex. The specimen is an internal mold. 

In the pedicle valve two prom~ent dental plates extend one-fifth the length. In the 

brachial valve a sharp median septum extends about half the length of the shell·or a trifle less . 

. Posteriorly the septum is forked, and each of the two divisions supports a crural process. The 

latter extend anteriorly and toward the pedicle valve and diverge only very slightly. . There 

is no cardinal process. · 

Locality: Chapman sandstone, west side of Edmunds Hill, Chapman Township, Aroostook 

County, Maine. 

1 Williams, H. S., and Gregory, H. E., Contributions. to the geology of Maine: U.S. Geol. Survey Bull. 165, p. 58, 1900. 

~ 

I 
\ 

, 

MOLLUSCOIDEA. 

Genus RHYNCHONELLA De Waldheim, 1809. 

(Rhynchonellldm incertm sedls.) 

RnYNCHONELLA cf. R. MAINENsrs Billings. 

Plate VI, figure 12. 

cf.J869. Rhynchonella mainensis. Billings, Portland Soc. Nat. Hist. Proc., vol. 1, pt. 2,·.p. llO, pl. 3, fig. 4. 

]~imestone of Square Lake [of Helderberg age]: Square Lake, Aroostook County, Maine. 

67 

d. :1.900. Rhynchonella nwinensis. Billings, quoted in Williams and Gregory: U. S. Geol. Survey Bull. 165, p. 69, 

pis. 1,·2. 

J~imestone of Square Lake [of Helderberg age]: Square Lake, Aroostook County,, Maine. 

A few specimens of obscure rhynchonellids from the Chapman sandstone are ~eferred with 

some hesitancy to Billings's species R. mainensis, from the Helderbergian Square Lake limestone of Maine. The brachial valve figured shows the presence of a very small, thin raised line 

representing the cardinal process. There is no trace of median septum and the dental sockets 

are 1ninute and do not exhibit crenulations. The surface is marked by about 21 low, rounded 

plications, six or seven of which are slightly raised to form a fold. The resemblan~e to the 

variable for1n called R. mainensis by Billings is external, as little is known of the internal character of that species. The internal characters recall some features of the genus Pugnax and 

ren1ove it from. the genus Stenoscisma. The shells lack, however, the external expression usually associated with Pugnax and confor1n superficially with Stenoscisma. 

Locality: Chapman sandstone, Edmunds Hill, Chapman Township, Aroostook County, 

Maine. 

U.S. National Museum, catalogue No. 59717. 

Genus EATONIA Hall, 1857. 

The term Eatonia may be applied t'o certain rhynchonellids of characteristic surface expression, distinguished. primarily by having the anterolateral portions of the pedicle valve concave. 

The two valves a.re very unequal. The brachial valve is convex; the pedicle valve is depressed 

on the umbone, concave in front and near the middle; sinus and fold are present and generally 

prominent. The internal features are of doubtful constancy among the different species. The 

internal features are a median septum in the brachial valve (a constant feature) and a distinct 

cardinal process which is bifurcate and rests on the short median septum. In the pedicle 

valve there are no dentalla.mellre except in Rhynchonella palumbina Barrande and R. (Atrypa) 

magr.era Barrande, and the rnusculature .is large and deeply impressed. The margin is denticulate internally. · 

The shells may be easily recognized by the n1arginal recurvature in the pedicle valve. 

The surface sculpture is very variable, but is chiefly of three or possibly four kinds, and serves 

to divide Eatonia into three groups, as follows: 

Subdivisions of genus Eatonia. 1 

By C. L. BREGER. 

A. Group of Eatonia peculiaris Conrad. Surface covered with fine threadlike striations. 

1. Eatonia peculiaris Conrad (genotype). New Scotland limestone, of :the Helderberg group, but chiefly in the 

Oriskany sandstone: New York, New Jersey, Pennsylvania, Maryland, Virginia, and equivalent beds in 

New= Brunswick, Quebec, Maine, and Ontario. 

2. Eatonia singularis Vanuxem. ~elderberg group, horizon of the ;New Scotland limestone and higher: New 

York, New Jersey, and equivalent beds in Tennessee an.d Missouri. . 

3. Eatonia pumila Hall. Oriskany sandstone: New York and West Virginia. 

4. Eatonia peregrinits Drevermann, Palaeontographica, 1902, p. 105, pl. 12, figs. 17-19. Lower Coblenzian graywacke: O~erstadtfeld, in the Eifel, Germany. 

• Jror roforoncos to tho literature and range of the American species, see Schuchart, Charles, Synopsis of American fossil Brachiopoda: U. s. 

Oool. Survey Bull. 87, 1897; Lower Devonieaspect of the Lower Helderberg and Oriskany formations: Oeol .Soc. America Bull., vol. 11, pp. 241-332, 

1900. 
68 FAUNA OF THE CHAPMAN SANDSTONE OF MAINE. 

A1 • Subgroup of Eatonia thetis (Barrande). Surface smooth, devoid of radial striations or ribs; resembles decorticated 

specimens of group A. 

1. Atrypa thetis Barrande, Syst. silur. Boheme, pls. 86, 133. Etage F 2 (Konieprussian; Eo-Devonian); Konieprus, Bohemia. Also recorded from etages G1, G3 (Meso-Devonian), E2 (Lower Ludlow-Aymestrian; 

Silurian), and E 1 (Wenlockian; Silurian). 

2. Atrypa harpya Barrande, idem, pl. 88. Etage E2 (Lower Ludlow-Aymestrian; Silurian): Dlaua-Hora, 

Bohemia. 

3. Atrypa magrera Barrande, idem, pl. 86. Etage E2 (Lower Ludlow-Aymestrian; Silurian): Dlaua-Hora 

and Hinter Kopanina, Bohemia. 

B. Group of Eatonia medialis Vanuxem. Surface covered with broad plications. 

1. Eatonia medialis Vanuxem. Coeymans limestone to Onondaga ("Corniferous") limestone, chiefly horizon 

of New Scotland limestone: Canada, New York, New Jersey, Pennsylvania, Maryland, and Maine. 

2. Eatonia eminens Hall. New Scotland limestone, of the Helderberg group, and equivalent·beds: New York 

and Tennessee. 

3. Eatonia whitfieldi Hall. Oriskany sandstone: Maryland. 

4. Eatonia sinuata Hall. Oriskany sandstone: Maryland. 

5. Rhynchonella eucharis Barrande, Syst. silur. Boheme, pls. 26, 31. 

6. Rhynchonella palumbina Barrande, idem, pl. 113. 

7. Rhynchonella velox Barrande, idem, pl. 33. 

8. Rhynchonella prosperina Barrande, idem, pl. 30. 

9. Rhynchonella corvina Barrande, idem, pl. 29. 

10, Atrypa matercula Barrande, idem, pls. 34, 113, 135. 

11. Atrypa alecto Barrande, idem, pl. 34. 

12. Atrypa? disjuncta Barrande, idem, pl. 35. 

Nos. 5-12 from etage F2 (Konieprussian; Eo-Devonian): Konieprus, Bohemia. 

13. Rhynchonella nympha Barrande, idem, pls. 29, 93, 122. Sameformation and· locality; also recorded from 

etages E2 to G1, inclusive. 

15. Rhynchonellafamula Barrande, idem, pl. 35. Etage E2 : Bohemia. 

14. Rhynchonella minerva Barrande, idem, pl. 32. Etage E2 (Lower Ludlow-Aymestrian): Dlaua-Hora, Bohemia. 

16. Rhynchonellafamula var. modica Barrande, idem, pls. 35, 140. Etage E2, Bohemia. 

17. Rhynchonella coronata Kayser, Deutsch. geol. Gesell., 1871, p. 512, pl. 9, fig. 5. Crinoid beds of the Eifelian 

(Meso-Devonian): Prum, in the Eifel, Germany. 

?18. Rhynchonella gainesi Nettelroth. Jeffersonville ("Corniferous") limestone and Sellersburg limestone (of 

Hamilton age): Kentucky and Indiana. This species seems to have a median septum and an Eatonia-like 

convexity. If the Konieprussian Rhy~honella prrecox of Barrande (op. cit. pl. 29) possesses' a septum,' it 

too may be placed in this group. Bo.th species resemble Pugnax superficially. In fact, a median septum 

is known to be developed in Pugnax pugnus from Ithaca, N.Y., and therefore it may be necessary to 

remove that species from Pugnax and place it elsewhere, perhaps in Eatonia. 

?19. Rhynchonella rudis Hall. New Scotland limestone, of Helderberg group: New York. 

20. Rhynchonella planiconvexa Hall. New Scotland limestone, of Helderberg group: New York. 

C. Group of Rhynchonella henrici l3arrande. Surface covered with a large number of narrow, low riblets, somewhat 

as in Wilsonia and Uncinulus. 

1. Eatonia coulteri Miller and Gurley. Beds of Oriskany age: Illinois. 

2. Rhynchonella obsolescens Barrande, op. cit., pl. 113. Etage F2 : Konieprus, Bohemia. 

3. Rhynchonella henrici Barrande, idem, pis. 25, 37, 130, 131. Etage F 2 : Konieprus and Mnienian, Bohelnia. 

Taunusian and Lower Coblenzian: Germany and Belgium. 

4. Rhynchonella henrici var. vellerosa Barrande, idem, pis. 130, 131. 

5. Rhynchonella henrici var. excavata Barrande, idem. 

6. Rhynchonella henrici var. laminaris Barrande, idem. 

7. Rhynchonella henrici var. excisa Barrande, idem. 

8. Rhynchonella henrici var. extenuata Barrande, idem. 

Nos. 4 to 8 from etage F2 , Konieprus and Mnj.enian, Bohemia. 

To group C may probably be added the following: 

Eatonia eijeliensis Drevermann, op. cit. Lower Coblenzian: Eifel district, Germany. 

Rli/ynchonella sanctamichaelis, Kayser, op. cit. Hauptquarzit: Germany. 

Rhynchonella pila Schnur, Palaeontographica, vol. 3, 1853, pl. 26, fig. 1. · Eifelian (Meso-Devonian): Germany. 

Rhynchonella primipilaris Schlotheim; see Schnur, idem, fig. 3. Eifelian: Germany, Belgium, France, Great Britain. 

The species named below, previously :.;eferred to Eatonia by authors, do not belong to the 

genus. 

Eatonia variabilis Whiteaves, Contributions to Canadian Paleontology, vol. 1, p. 2331, pl. 29, figs. 6-9. Late MesoDevonian: Hay River, Canada. 
MOLL USCOIDEA. 69 

Eatonia goodlandensis Kindle and Breger, Indiana Dept. Geol. and Nat. Res. Twenty-eighth Ann. Rept., 1904, p. 439, 

pl. 8, figs. 10-12. Eo-Silurian: Goodland, Ind. (A species of Mimulus.) 

Atrypa assula Barrande is regarded by Schuchert 1 as a probable equivalent of Eatonia 

peculiaris. Neither Barrande's nor Whiteaves's species is rhynchonelloid. 

EATONIA SINGULARIS (Vanuxem). 

Plate \,'I, figures 8, 18. 

1842. Atrypa singularis. Vanuxem, Geology of New York, Rept. third district, p. 120, fig. 3. 

Catskill shaly limestone: Third district, New York. 

1859. Eatonia singularis. Hall, Paleontology of New York, vol. 3, p. 243, pl. 38, :figs. 14-20. 

Shaly limestone of the Lower Helderberg group: Helderberg Mountains, Schoharie, Carlisle, Hudson, Catskill, 

and other pla.ces in New York. , 

1876. Eatonia singularis. Barrett, Lyceum Nat. Hist. New York City Annals, V<?L 11, p. 295. 

Delthyris shaly limestone: Bennett's quarry, Port Jervis, N.Y. 

1882. Eatonia singularia. I. C. White, Pennsylvania Second Geol. Survey Rept. G6, p. 134. 

Stormville limestone: Pike County, Pa. 

1882. Eatonia singularis. Stevenson, Pennsylvania Second Geol. Slll'vey Rept. I2, pp. 104, 134. 

Basal Oriskany: Near Hyndman, Bedford County, Pa. 

Lower Helderberg chert beds: Up Beaverdam Run road on Pine Ridge in King Township, Bedford County, Pa. 

1889. Eatonia sin[tularis. Lesley, Dictionary of fossils, Pennsylvania Second Geol. Survey Rept. P4, vol. 1, p. 213, figs. 

Lower Helderbfirg chert beds: Perry County, Pa. · 

1893. Eatonia singularis. Hall and Clarke, Paleontology of New York, vol. 8, pt. 2, p. 206, pl. 61, figs. 13-16. 

Lower Helderberg group (shaly limestone): Albany County, N.Y. 

1897. Eatonia singularis. Schuchert, U. S. Geol. Survey Bull. 87, p. 220. 

Lower Helderberg: Schoharie, N.Y. 

1900. Eatonia singularis. Schuchert, Geol. Soc. America Bull., vol._11, p. 284. 

Lower Helderberg: Maryland and Virginia; Tennessee; New York; Gaspe, Quebec; and Nova Scotia. 

New Scotland beds: New York. 

1901. Eatonia s1:ngularis. Prosser, New York State Geologist Eighteenth Ann. Hept., p. 58. 

New Scotland shaly limestone: Altamont, N.Y. 

1903. Eatonia singularis. Schuchert, U. S. Nat. Mus. Proc., vol. 26, p. 422. 

New Scotland limestone: Twenty-first Bridge, Baltimore & Ohio Hailroad, near Keyser, :Mineral County, W.Va. 

Lower New Scotland cherty limestone: Western Maryland. 

1903. Eatom:a s~:ngularis. Weller, New Jersey Geol. Survey, Paleontology, voL 3, pp. 89, 311, pl. 36, figs. 24-27. 

New Scotland cherty limestone and higher shaly beds: One-half mile below Hainesville, N.J. 

1903. Eatonia singularis. Van Ingen and Clark, New York State Mus. Bull. 69, pp. 1203, 1207. 

Oriskany (sanely and cherty beds): Glenerie, N.Y. 

1905. Eatonia singularis. Shimer, New York State Mus. Bull. 80. 

Lower New Scotland shales: Trilobite Mountain, N.Y. (pp. 222, 223, 224, 245, 264). 

Port Ewen (arenaceous limestone): Trilobite Mountain, N.Y. (pp. 134, 234, 245, 264). 

A single specimen from the Chapman saU:dstone of Edmunds Hill agrees in essential particulars with the typical forms of the species from New York. The specimen has both valves 

in conjunction and is partly exfoliated. Outline cordate; umbones broadly obtuse, margins 

evenly rounded, slightly insinuate in front; length less than the width, greatest width at 

anterior third. Length, 18 millimeters; width, 2l millimeters; depth, 12 millimeters. Pedicle 

valve depressed convex over the umbo; in the middle and anteriorly the surface is concave 

from the margin inward. A deep, broad sinus begins at or near the middle, becomes more 

and more prominent anteriorly, and produces on the front margin a lingual extension which 

is at nearly right angles with the plane of the margin. The sinus is deeply but not abruptly 

excavated; its Inat·gin is indefinite. On the interior of the pedicle valve the musculature is 

strongly pronounced; the cicatrix is deeply excavated in the shell posteriorly, while anteriorly 

it seems to be a little elevated; it is rather elongately oval in outline and extends about half 

the length. Dental and delthyrial structure not observed. The brachial valve is strongly 

cqnvex, the.greatest elevation of the general surface being at the anterior third. Posteriorly 

the surface declines toward the beak. A fold is feebly developed near the beak but near the 

1niddle becomes more pronounced and is very highly elevated near the front margin. In the 

.present specimen the lateral margins are closed, but the shell is gaping in front between the 

1 Geol. Soc. America Bull., vol. 11, p. 264, 1900. 
70 FAUNA OF THE CHAPMAN SANDSTONE OF MAINE. 

front edge of the fold and that of the sin11s. This gaping may be due to fracture. On the 

interior of the brachial valve a broad septum was observed. Its detailed structure is not 

apparent. The surface is marked by fine, even radial lines, which are low, rounded, and 

closely set. There are four lines in the space of 1 millimeter. They cover both fold and sinus 

and in front of the sinus two of them become thickened. On the fold there is a sunken area 

near the front edge bounded by two riblets, one on each side. The ornamentation does not 

show very distinctly in the figures on Plate VI. 

Locality: Chapman sandstone, west side of Edmunds Hill,. Chapman Township, Aroostook 

County, Maine. 

U.S. National Museum, catalogue No. 59718. · · 

Oomparisons.-Eatonia singularis differs from E. peculiaris in having the fold on the 

. brachial valve extending to the umbo; in the latter it ·does not extend back of the middle. 

In the Maine· specimen the fold extends apparently to the umbo, but is obsolescent posteriorly. 

The outline is broadly cordate, as in typical E.· singularis, while in typical E. peculiaris the 

outline is more elongate and the shell is proportionally narrower, though this is not a persistent 

distinction. 

Stratigraphic value of Eatonia.-The genus Eatonia in the North American faunas attains a 

profuse development in the Helderberg and Oriskany, both in species and in individuals, and 

in plasticity of each of the species. In Europe Eatonia attains its greatest dev:elopment in 

species and' individuals in beds referred by most authors to the Lower and Middle Devonian. 

The time range of the genus Eatonia is from late Silurian to Middle Devonian. 

In the American ·faunas typical Eatonias were for a long time unknown above the Oriskany, but the genus is by no means rare in the '' Corniferous" of Illinois.1 This occurrence in 

·Illinois is interesting in connection with the fact that from t4e beds of Oriskany age in Illinois 

there has been described Eatonia coulteri of Miller and Gurley, the only known North American 

equivalent of the European group of E. henrici (Barrande), which is widespread in the 

Taunusian and Lower Coblenzian. This occurrence of European types in the Mississippi Valley 

in the Lower Devonian and their absence in New York recall a similar contrast sho:wn by the 

Middle and Upper Devonian faunas of Manitoba, where Stringocephalus burtuni and other species 

occur, respectively, with their European ·associates, these species being either unknown or very 

rar~ in New York and other parts of eastern America. 

The ~xtension of Eatonia stratigraphically downward into the typical Silurian is shown in 

the Moydart formation of Arisaig, Nova Scotia1

2 and in the Silurian of the Baltic Province, on 

the island ·of Gotland, where two species are reported by Lindstrom. 3 

In regard to the stratigraphic position of the Konieprus group, or etage F2 of the Bohemian 

·series, in which Eatonia.is prominent, n1uch has been written, particularly concerning its relation 

to the Helderberg of North America. Schuchert has suggested the'' similarity" of many species 

of the Konieprussian with American Helderbergian fossils. The Konieprus beds are now 

generally correlated with the Lower Devonian of Europe and North America. The fact that the 

etage F 2 of Barrande is not homogeneous has been recognized by many geologists, but seems 

to have been passed over with no further attention. .The upper part of the Konieprus group 

contains many brachiopods and other fossils along with goniatites, which give to it the aspect 

of a fauna near the American Onondaga ("Corniferous"). or even the Marcellus. Etage Ft, 

the Tentaculite limestone, with the dmni.nant Spirifer inchoans Barrande, underlies the Konieprus group. Its fauna resembles that of the American Manlius ("Tentaculite ") limestone 

with Spirijer vanuxemi Hall. The Konieprus limestones of etage F2 are known to bridge several 

time, stratigraphic, and faunal gaps, including several successive coral-reef horizons,. and it is 

becoming apparent that some of the fossils formerly supposed to represent approximately the . 

same horizon may belong to several different successive faunas, which in the American succession range from the Helderberg through part, at least, of the Onondaga or "Corniferous" ~nd 

! 'Veller, Stuart, Jour. Geology, vol. 5, p. 627, 1897. 

2 Am. Jour." Sci., 4th ser., vol. 28, p. 162, 1909. 

a Lindstrom, G., Ueber die Schichtenfolge der Silur auf der Insel Gotland: Neues Jahrb., 1888, vol. 1, pp. 147-164. 
MOLL USCOIDEA. 71 

possibly to the :Marcellus. Bohemian species of etage F 2 and closely related species which 

have been recognized in EuTope outside of Bohemia occur chiefly in the Lower Coblenzian 

and the Taunusian. 

Genus BEACHIA Hall and Clarke, 1893. 

'BEACHIA CHAPMAN! sp. nov. 

Plate XXV, figme 27. 

A large specimen of a brachial valve of a distinctly rensselaeroid type is referred to the 

genus Beachia, chiefly because of its close resemblance in outer form to f':Jll-grown specimens 

of Beachia suessana, although it is evidently distinct from that species. The form is elongate 

ovoid, widest behind, with a broad, nearly straight posterior margin. The specimen is 40 

Inilli1neters long, 37 n1illi1neters wide (the greatest width is at two-fifths the distance from 

beak to front), and 5 1nillimeters high (at one-fourth the distance from beak to front). The 

shell is broad shouldered, the lateral' margins converging, convex throughout, and marked by 

fine radial lines which extend nearly to the beak on the sculpture cast. 1 

This shell has the outline and convexity of Beachia suessana, but the radial surface lines 

are finer and 1nore persistent than in that species. The specimen is also larger than typical 

specin1ens of Beachia amplexa Clarke and 111egalanteris thunii Clarke, from Grande Greve and 

Perce Rock; in the large size it is particularly comparable with the latter species. The ChapJnan specimen, however, has finer radial surface markings and the mid part of the shell is more 

strongly produced anteriorly. The difference between the genera Beachia Hall and Megalanteris Oehlert is -based on details of the structure of the brachidiun1 1

2 and although specific 

differences 1nay be defined, it is difficult to determine, in the absence of the evidence of internal 

characters, to which of these two genera particular specimens may properly be assigned. Clarke 

ernphasizes these difficulties in discussing his species Beachia amplexa in the monograph on the 

early Devonian history of New York and eastern North America. 

Locality: Chapman sandstone, Edmunds Hill, Chapman Township, Aroostook County, 

Maine. 

U.S. National :Muse:um, catalogue No. 59719. 

Genus MEGAL.ANTERIS Oehlert, 1887. 

:MEGALANTERIS ~ sp. 

Plate VI, figure 15; Plate VII, figure 15. 

Two small, smooth pedicle valves of slight convexity and very obtuse umbones express in 

their outline and surface curvature a general likeness to the form of Megalanteris ovalis. Outline rounded, oval, or suboval; slightly wider than long. Posterior margin subtending an 

angle of 145° or more, abruptly inflected to. the hinge, producing a narrow pseudo-area; greatest 

width near the middle or somewhat posterior. Outline co01pares closely with Megalanteris 

ovalis. Shells convex, not inflated; greatest elevation at posterior third or fourth equals onesixth to one-seventh the length. .On the interior two short, nearly parallel dental lamellre; 

n1usculature not impressed in the valve; vascular markings radial, not flexuous, nor evidently. 

branching, apparent in front of the region where the n1usculature is presumed to be. The 

internal molds are entirely devoid of traces of surface ornamentation, but the specimens. indicate a smooth shell of the Cryptonella-:Meristella surface expression. The present specimens 

differ from the Meristellas in having the umbone very obtuse, in their depressed convexity, 

in their absence of 'fold or sinus, and in their lack of any impressions of the musculature ·on 

internal molds. · 

Locality: Chapman sandstone, west side of Edmunds Hill, Chapman Township, Aroostook 

County, Maine. 

U. S. National Museun1, catalogue No. 59720. 

1 'l'ho term "sculpture cast" is used to designate an internal mold which shows surface markings. Sculpture casts, showing characters of both 

tho interior lllld tho exterior of tho shell are produced when the shell is dissolved out in the rock, leaving at first two distinct impressions, the internal 

mold and tho external mold; by the tectonic compression of the rock these two impressions are squeezed against and modify each other. 

2 Now York State Mus. Mom. 9, p. 166, 1908. 
72 FAUNA OF THE- CHAPMAN SANDSTONE OF MAINE. 

Genus RENSSELAERIA Hall, 1859 .. 

RENSSELAERIA MAINENSIS Williams. 

Plate VI, figure 11; Plate XI, figures 1-15. 

1900. Rensselaeria mainensis. Williams, U. S. Geol. Survey Bull. 165, pp. 79, 80. 

Chapman sandstone (Eo-Devonian): Presque Isle Stream, Edmunds Hill, and Mars Hill (localities 1099 A, B, C), 

Chapman, Aroostook County, Maine. 

1907 (April). Rensselaeria mainensis. Williams, U. S. Nat. Mus: Proc., vol. 32, pp. 267-269, 2 figs. 

Chapman sandstone (Eo-Devonian): Presque Isle Stream, etc., Maine. 

1907 (May). Rensselaeria atlantica. Clarke, New York State M_us. Bull. 107, pp. 243-247, figs. 

Presque Isle Stream and Edmunds Hill, Chapman, Aroostook County, Maine. 

Shells rensselaeroid, of medium to large size;· biconvex, the pedicle valve more convex 

than the brachial; surface multicostate; beak elevated in the pedicle valve, showing the welldeveloped cardinal area. Pedicle valve elongate ovate; greatest width at the shoulders, posterior to the middle. Length a trifle greater than the width, generally in the proportion 9 : 8 

but varying from 12 : 11 to 6 : 5, except in some specimens, probably fractured and incomplete in front, in which the width is a little greater t4an the length. The beak is pointed, 

strongly incurved, and elevated but not curving over nor appressed against the brachial valve. 

The posterior margin is obtusely angular, inclosing an angle of 115°. to 140°. The posterior 

edge of the shell extends in a straight line from the beak for some distance till it curves into the 

broad, rounded shoulders. The lateral margins are curved· near the shoulders and are subparallel, so that the greatest width of the shell is indefinitely posterior to the middle-in some 

specimens just back of the middle, in others one-fourth the distance from beak to front. Below 

the shoulders the lateral margins converge more or less rapidly and merge into the front margin, 

which is strongly curved parabolically and not demarcable fr01n the lateral margins: 

The pedicle valve is gibbous throughout. The longitudinal profile is unsymmetrical; the 

maximum height is from one-fifth to nearly two-fifths the length fron1 the beak and is equal to 

about one-third the length of the shell. 

The umbo is tumid and the beak strongly incurved. Fro1n the umbo the surface slopes 

down to the sides rather flatly, giving the shell a subcarinate appearance in transverse section. 

In front the slope is more rounded. 

A large pedicle valve has a length of more than 40 millimeters (length in this shell is measured 

in a straight line from the tip of the beak to the front of the n1argin), but the common length 

at Presque Isle Stream, where the species is most abundant and varied, is from 24 to 32 millimeters. The smallest specimen seen had a length of 10 millimeters. The width similarly 

varies from 9 to 4.3 millimeters; the typical specimens have a width of 26 to 31 millimeters. 

The cardinal area is, for a rensselaeroid, unusually well developed. It is triangular, large, 

and extends very nearly the whole width of the shell, producing a wide, straight hinge line, 

the height of which is one-sixth to one-third as great as the width. The general plane of the 

cardinal area is at an angle of approximately 180° to the plane of the margin; rarely a few·. 

degrees more, more commonly a few degrees less. The area is, however, rarely plane but is 

more commonly curved or arche<;l, especially j~st under the beak, and is strongly striate horizontally. The delthyrium is large and triangular, the sides including an angle of about 60° or, 

rarely, a little more, with sides com1nonly slightly curved, the convex sides of the curves facing 

each other. The delthyrium is open, as can be seen in a couple of specimens at hand a,nd as is 

further indicated by the fa,ct that the sand filling of the internal 1nold is always continuous 

through the delthyrium with the external rock matrix, which it could not have been if any 

deltidium intervened between the interior of the shell and the exterior. No true deltidial 

plates have been observed, but structures simulating them seen1 to be produced by the protrusion outward through the delthyrium of the callous deposition, in the senile stage, of shelly 

matter on the interior. 

The pedicle valve is extraordinarily thickened on the interior by a poi1derous deposit of 

prismatic calcareous material in the region of the urribones. The prisms are well developed 
MOLL USCOIDEA. 73 

and normal to the surface. In the larger shells, about 35 millimeters long, this deposit is 6 

1nillilueters in thickness. In n1ost specimens of adult size, also, the umbonal portion of the shell 

is greatly thickened, particularly in the umbonallateral slopes, but to a less degree than in the 

huge adult shell. On the interior of the larger pedicle valves there was apparently no cavity 

in front of the cardinal area; all this space appears to have been filled to the hinge line by calcareous shell substance, so that internal molds and sculpture casts do not show any indication 

of cardinal area. The front of the shell is rather thin and is marked by pronounced radial 

plications. Dental lamellre support the teeth. These lamellre are parallel a~d very short, 

reaching only to tho posterior margin of -the diductor scar. They are fairly prominent and 

sharply elevated in shells in which there is little shelly deposition about the umbo; but in the 

. ln.rger, greatly thickened shells the cavity on the outer side of the dental lamellre is entirely 

filled in, so that the lamellre hardly project above the base of the shell and, in internal molds, 

do not leave the characteristic incision. In such clean internal molds of thickened pedicle 

valves traces of the dentallamellre may be seen as curved .blunt incisions surrounding the pedicle 

nnd visceral ( ~) cavity back of the muscular scars. In these old shells, also, the muscular scars 

and pedicle cavity occupied deep excavations, showing, in internal molds, as prominently elevated tracts, the lateral boundaries of which are the inside edges of the old dental hunellre. 

The muscular scars are distinct in the pedicle valves of shells where there has been no thickening deposition; in the larger and thicker shells they are very prominent and give a characteristic appearance to the fossil. The diductor cicatrix is elongate, about twice as long as wide, 

and extends nearly to the middle of the valve-that is, to tl;le mid length along the periphery, 

not in a straight line fr01n the front 1nargin to the tip of the beak. The sides are distinct and 

in unthickened shells are marked by a f~'tint elevated line which is the continuation of the dental 

lamellre. In the thickened shells the musculature is very deeply excavated and produces, in 

internal molds, an elongate, elevated tonguelike ridge. Anteriorly the muscular scars become 

obsolescent. The adductor scar is rarely discernible but is very elongate, spindle shaped, and 

not divided. It begins in front of a narrow spearhead-like median ridge which divides the posteriOI· portion of the diductor scar in two. Posteriorly, the diductor scar ends about halfway 

between its front Intugin and the tip of the beak; and the umbonal portion of the shell is n1arked 

by a deep trihedral pedicle cavity. This. large pedicle cavity is bounded on the side by the 

dental lamellre; as has been indicated, the dental lamellre end above and do not reach the 

diductor scar. · 

The brachial valve is convex throughout, including the shoulders, but less convex than the 

pedicle valve. In outline it is rounded trigonal to subcircular; the width is equal to or slightly 

gren,ter than the length, greatest \vidth posterior. Hinge line strt1.ight; posterior n1argin varies 

fron1 neu.rly horizontu.l to vet·y obtusely angular and curves into the broad, rounded shoulders; 

lateral and front n1argins curved into a semicircle. The longitudinal profile is an unsymmetrical curve deepest at one-third the distance from the hinge and in uncrushed specimens equal 

to two-ninths to one-third the length of the valve. The umbonal portion is tumid and includes 

about a quarter of a circle. The slope for the anterior two-thirds is low convex. The trans-

_verse profi.le is rounded or slightly subcarinate. 

The dimensions, in millimeters, of some of the specimens are as follows: 

Length. . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . 27 21. 5 29 24 23 26 24 

Widt.h .......................................... 27.5 26 29 27.5 25 28.5 29 

The dental sockets are obscure. The crural bases are narrow and cylindrical and rest on 

and n1erge into the cardinal process. The cardinal process is massive and has a convexly 

rounded, broad, platform-like surface for attachment of the diductor muscles. This attaching 

surface is obscurely bilobed, though there is commonly no sharp distinction of divisions. 

Beneath this bilobed cardinal process, and forming a base for it, are two broad calluses separated 

by a strong Inedian groove, which is continued as a tubular tunnel under the cardinal process. 

It is probable also that the two calluses may have been connected and united above by a 

platfonn-like bridge, forming an undivided hinge platform under the n1cdian portion of which 

extended the visceral canal or tunnel. This tunnel is preserved in a few internal 1nolds as a 
74 ' FAUNA OF THE CHAPMAN SANDSTONE OF MAINE. 

sandy connecting dissepiment extending from a point behind the muscular scars to the tip of 

the beak; underneath (in molds) is a broad, deep cavity left by the dissolving away of the 

calluses and massive cardinal process. This sandy dissepiment is marked by a groove indicating 

a continuation of the dorsal median septum. The hinge platform consists, therefore, of two 

thick, broad calluses supporting a massive ~ardinal process which is indistinctly bilobed. 

Between the calluses there is a deep groove which extends as a tunnel under the cardinal 

process and which may possibly be canopied by a platform uniting the two calluses. 

The musculature of the brachial valve is characteristic. The two adductors are distinct 

and in older shells become conspicuous. Th!3y are elongate-oval or subreniform, extend from the 

base of the calluses to about the middle of the shell, and together inclo.se a subcircular area. 

Posteriorly the two adductors are broadly separated by a strong ridge which in good specimens 

is $een to be tripartite. This ridge, which is an elevated continuation of the visceral canal 

between the calluses, is about one-fourth or one-third the width of the musculature, but does 

not extend more than half its length. The median division of this ridge is an elevated, very fine, 

sharp line (a thin median septum) and is continued into the visceral canal to the tip of the beak. 

In some well-preserved specimens the median line or septum extends three-fifths the length of 

the shell; in other specimens it ends near the middle o.f the musculature and in front of the 

middle the two adductor scars are separated by a sharp impressed groove instead of by the 

elevated line. The posterior margin of the adductors is conspicuous by the abrupt beginning of 

the calluses of the hinge plate. The scars are here broadly separated by the thick median ridge. 

Anteriorly the margin of the musculature is obscure and the scars closely approach each other. 

In most well-preserved old specimens the scars are distinctly wrinkled transversely, and in two 

specimens about 16 strong transverse wrinkles were present. 

The shell structure is strongly fibrous, the fibers ext~nding forward from the outer surface to 

the inner at a very oblique angle. In the thickened umbone of the pedicle valve the fibers are 

sometimes nearly normal to the surface and are segregated into coarse prisms, which are 

transversely striate. No punctffi have been observed under a hand glass magnifying more than 

4 diameters, and if they exist at all in these early terebratulid shells they must be extremely 

minute. The shells may be recognized by their multicostate ornamentation. The ribs in 

mature specimens vary from 48 to 75 in number, but are most commonly between 60 and 65. 

On the surface they are well rounded, separated by narrower furrows and very prominent from 

beak to front. On internal molds the impressions of the ribs are well preserved forward and 

laterally but obsolescent in the muscular areas and posterior third of the shells; on these internal 

molds the ribs are strongly elevated and rounded, and the interspaces are a little wider than on 

the surface. The ribs are generally simple, but in a few spe·cimens they increase by bifurcation. 

No indication of concentric lines has been observed and only occasional varices of growth. In 

very young shells, from 6 to 10 millimeters in length, the number of ribs is between 19 and 34, 

and the ribs are as strongly n1arked, relatively, as in adults. The number of ribs increases to the 

larger number present in older shells chiefly by the addition of new costffi on the lateral margins, 

rarely by bifurcation of one or two ribs. 

Locality: Chapman sandstone at Edmunds HiU, Presque Isle Stream, and 2~ miles west of 

Presque Isle Stream, Chapman Township,' Aroostook County, :Maine. 

U. S. National Museum, catalogue Nos. 59721 to 59726. 

Comparisons.-The species may be distinguished from the common American Rensselaerias 

by·its strong plications, cardinal area, elevated beak, and open delthyrium. Among American 

species Lissopleura equivalvis/ from the Helderberg group (Coeymans and New Scotland limestones) of New York, is superficially very similar. That species, however, has an acute urn bone; 

its greatest width is in front of the middle; its brachial median septum is much stronger; it has 

strong, fine concentric markings; its radial ribs are flatter topped; and it never attains the size 

of mature specimens of Rensselaeria mainensis. Internally the shells are quite different. Some 

1 Rhynchonella equivalvis Hall, 1857; see Paleontology of New York, vol. 3, p. 224, pl. 29, figs. 2-3, 1859. Also Lissopleura equivalvis Whitfield, 

Am. Mus. Nat. Hist., Bull., vol. 8, p. 232, figs. 1-5, 1896. 
MOLL USCOIDEA. 75 

rather small specimens of exteriors of the Maine species might be mistaken for Lissopleura 

eq_uivalvis, but the two species are distinct .internally. Very small specimens of R. mainensis 

1night also be 1nistakcn for R. mutabilis, for they have the same outline and the same number of 

ribs, but the ribs in the Maine Rensselaeria are muoh stronger than in R. mutabilis and the 

longitudinal proflie is different. · 

Among European shells Terebratula strigiceps Roemer ( =Rensselaeria stringiceps auct.), 

from the Lower Devonian, presents the nearest approach in superficial character toR. mainensis. 

It seeins, however, that this nan1e has been given by different writers to very different shells. 

The English shell,· so called by Davidson/ resembles a pentamerid of the Conchidium group, 

and the Upper Devonian species from Asia identified by Huddleston 2 with Roemer's species, is 

an entirely distinct shell of uncertain affinities. 

The :Maine species may be distinguished from the typical German form of R. stringiceps 3 by 

the elevated beak, exposing the characteristic cardinal area, the weaker septun1.in the brachial 

valve, the broader, less elongate outline with the greatest width posteriorly, and the larger 

nu1nber of ribs (40-44 in the European fossil). R. stringiceps is regarded by Schuchert 4 as a 

pentn.merid. , 

Rensselaeria mainensis also resembles Megalanteris (" Beachia ") ovalis in internal feature, 

although exteriorly the two are decidedly distinct. There is a remarkable identity in the 

chn.racter of the muscular imprint n.nd the hinge pla~e. · Internal molds of R. 1nainensis show at 

the beak of the brachial valve two widely separated deep circular holes (imprints of the crural 

bn.ses) n.nd the massive cardinal process extending up into the pedicle valve musculature, 

almost exactly as in specimens of Megalanteris ovalis. The musculature is also very similar in 

size, outline, markings, sti'ength of impression, and septal characters, and the calluses and 

hinge plate are also similar. Although the brachidium is unknown, the present shell may be 

sn.fcly regn.rded as te~ebratulid, but whether it has the simple Centronella-Rensselaeria loop of 

tc Beacbia" or the more complex loop supposed to characterize Megalanteris can not be' stn.ted. 

It is a remarkable fact that though truly terebratulid shells are almost without exception 

punctn.te-sometimes so strongly so that the punctre are almost visible to the naked eye, as 

in Cryptonella-no indications of punctre have been observed in the present shells under a 

strong hand magnifying glass. Scaphiocmlia boliviensis Whitfield, a large plicated shell with 

sotne affinities to R. mainensis but with concave brachial valve, is likewise strongly fibrous, no 

punctre having been observed under a hand magnifying glass. The same is true of the Helderberg Lissopleura eg_uivalvis and Rensselaeria mutabilis. It is possible that punctre n1ay exist 

in these shells, but if so· they are extremely minute. Among the more recent Terebratulidre the 

con.rsest punctre are one four-hundredth of an inch in diameter (in the Cretaceous ]fegerlia lima) 

n.nd the finest are one two-thousandth of an inch in diameter (Terebratula bullata, Jm·assic).5 . 

Punctre of the ln.tter size, especially if scattered, would not, it is believed, be visible under the 

ordinary hn.nd 1nn.gnifying glass. That some of the early plicate terebratulids were punctate is 

certain, for punctre have been observed by Oehlert in his Eo-Devonian Oentronella bergeroni,6 

n.nd Rensselaeria ovoides from the Oriskany is also punctate. Hall and Clarke regard the entire 

genus H.ensselaeria as punctate. 

t Renssclcteria stringiccps var.'? Davidson, British Devonian Brachiopoda, p. 10, pl. 4, figs. 5, 6, 7, 1864; Middle (?) Devonian, Hagginton Hall 

nom· llfrncombo, England. 

2 McMahon, C. A., and Huddleston, W. H., Fossils from the Hindu Khoosh, pt. 2, Paleontology: Oeol. Mag., decade 4, vol. 9, No.2, p. 56, pl. 3, 

fig. !J, 1!)02. 

a Kayser, Emanuel, Lohrbuch der geologischen· Formationskunde, p. 100, fig. 3, 1891. This is the usual figure of this species appearing in tho 

toxt books. 1'ho Sandborgors, in their work on the fossils of the Rhenish series in Nassau, figure ~he internal molds (pl. 33, figs. 14, 14n). Tqei.r 

flguro 14o. agrees well with Rensselacria maincnsis, but their figure 14 shows the distinctness of the German species. 

4 Oool. Soc. Amorico. Bull., vol. 11, p. 258, 1!JOO. More recently (in his paper on the Brazilian Devonian, Jour. Geology, vol. 14, pp. 722-746, 

l!JOG) Schuchort remarks of Rcn.~sclacria ('?) crassicosta: "These shells look more 1 ike Plethorhyncha spcciosa." 

o Co.rpontor, William, On the ultimate structure of the shells of Brachiopoda, in Davidson, Thomas, British fossil Brachiopoda, Introduction, 

p. 28, pis. 5, 6, etc., 1853. o 

o Soc. :Etudes sci. d' Angers Bull., separate, p. 1, fig. 9, 1885. 
76 FAUNA OF THE CHAPMAN SANDSTONE OF MAINE • 

. Family TEREBRATULID.tE Gray. 

Subfamily TEREBRATULIN.tE Dall. 

Genus EUNELLA Hall and Clarke. 

EUNELLA ELLS! (Clarke). 

Plate VI, figure 23. 

1907. Cryptonella(?) ellsi. Clarke, New York State Mus. Bull. 107, p. 237, figs. 

Lower Devonic: Grande Greve, Quebec. 

The specimen shows a narrow umbonal region, the posterior margins diverging from the 

beak at an angle slightly less than 60°, continuing thus for about four-sevenths the length of 

the shell, then curving rather abruptly into th.e anterior margin, which includes a semicircular 

arc of 180° .. The greatest width of the shell is anterior, between three-fifths and two-thirds the 

length of the beak. The length is 20.5 millimeters; width 14 millimeters. The longitudinal 

and transverse profiles ·are symmetrically arcuate; the greatest depth of the valve, 4.3 millimeters (in internal mold), is over the center. The surface is evenly rounded. The beak is very 

slightly recurved, marked by a fairly large circular foramen arching over a small delthyrium. 

As seen in longitudinal profile, the lateral margin of the valve is rather strongly sigmoidal. 

The solitary internal mold of the pedicle valve figured from Edmunds Hill represents a shell 

of the common smooth Terebratula or Meristella expression, which was originally placed in 

Meristella. It is probably not a Meristella, for there is no medial insinuation of the outline 

nor, more important still, are there any recognizable muscular impressions or pronounced 

dental lamellre, such as occur in Meristella and its spire-bearing allies. The absence of n1uscular impressions can not be due to imperfect preservation, for the mold is clearly and perfectly preserved, showing radiating vascular markings and the impression of what was a low, 

short, narrow median ridge or crest under the beak. The dental lamellre are very weakly 

developed, being hardly discernible, are subparallel to the posterior margin, and do not appear 

to have been extended over the base of the valve. 

The features preserved indicate a terebratulid having a narrow, elongate, triangular-ovate 

outline, with acute posterior margin (60° or less), so~ewhat like the Onondaga (" Corniferous ") 

Eunella sullivanti Hall. 1 The Chapman fossil differs from Eunella sullivanti in having a completely rounded, semicircular front margin, lacking the anterior truncation of Hall's Onondaga 

species. It also somewhat resembles Centronella. glansfagea, 2 a species hitherto regard~d as 

diagnostic of the Onondaga (" Corniferous "), which occurs in the coarse Oriskany sandstone at 

Union Springs, Cayuga County, N.Y. Compared with 0. glansfagea, the Chapman shell is more 

·acute, having an umbonal angle of less than 60°, and the circular foramen was apparently 

larger. In these features Eunella ellsi approaches E. sullivanti, but the \vell-developed ·Sinus 

or flattening in the front margin of E. sullivanti is not developed in the Chapman species. 

Locality: Chapman sandstone, west side of Edmunds Hill, Chapman Plantation, Aroostook 

County, Maine . 

. u.S. National Museum, catalogue No. 59726. 

Superfamily SPIRIFERACEA Waagen. 

Family SPIRIFERID.tE King. 

Genus CYRTINA Davidson, 1858. 

CYRTINA ROSTRATA (Hall). 

Plate V, figure 14. 

1841. Spirijer cuspidata. Phillips, 3 Paleozoic fossils of Cornwall, Devon, etc., p. 72, pl. 29, fig. 124 B. 

Middle Devonian: Barton, South Devon. . - o 

1857. Cyrtia rostrata. Hall, New York State Cab. Nat. Hist. Tenth Ann. Rept., p. 64. 

Oriskany sandstone: Cumberland, Md. 

1 See Hall, James, and Clarke, J. M., Paleontology of New York, vol. 8, pt. 2, pl. 80, fig. 2.5, 1893. 

2 Idem, pl. 79, fig. 3. 

a Erroneously identified with the Carboniferous Spirifer (Syringothyris) cuspidatus Sower by. 
MOLL USCOIDEA. 

1859. Cyrtia rostrata. Hall, Paleontology of New York, vol. 3, p. 429, pl. 96, figs. 1-6; pl. 98, fig. 8. 

Oriskany sandstone: Albany County, N.Y.; Cumberland, Md. 

1861. Cyrtina rostrata. Bi1lings, Canadian Jour., vol. 6, p. 263. 

Corn.iferous limestone: Lot 45, Cayuga, Ontario. 

1863. Cyrtia like C. rostrata. Billings and Logan, Geology of Canada, p. 428. 

Conuferous limestone: Famine River, Quebec. 

77 

1864. Cyrtina heteroclita var. rnulticostata. Davidson, British fossil Brachlopoda (Devonian), vol. 3, pt. 6, p. 49, pl. 9, 

figs. ll-14. 

Dev011ian: Barton and Lummaton, near Torquay, Devonshire. 

1876. Cyrtina rostrata. Barrett, Lyceum Nat. Hist. New York City Annals, vol. 11, p. 296. 

"Tr\lobite beds": Bennett's quarry, Port Jervis, N.Y. 

1877. Cyrtia rostrata. Barrett, Am. Jour. Sci., 3d ser., vol. 13, p. 387. 

Trilobite beds: Bennett's quarry, Port Jervis, N.Y. 

1882. Cyrtina heteroclita var. rnulti])licata. Barrois, Soc. geol. Nord Mem., vol. 2, p. 260, pl. 10, figs. 8 c d. 

Moniello limestone ( Calceola sandalina beds): Luanco, Asturias, Spain. 

Candas limestone (with Spirijer disjunctus): Candas, Asturias, Spain. 

1885. Oyrtina demarlii (not Bouchard). Maurer, Grossherzogl. hess. geol. Landesanstalt Darmstadt Abh., vol. 1, 

Heft 2, p. 164, pl. 7, fig. 6. 

Lower Devonian limestone: Waldgirmes, near Giessen, Germany. 

1887. Cyrtina dernarlii (not Bouchard). Tschernyschew, Com. geol. (Russe) Mem., vol. 3, No.3, p. 80, pl. 9, fig. 1. 

Middle or Upper Devonian: Wolchow, western Urals, European Russia. 

1889. Cyrtina rostrata. Schuchert, New York State Geologist Eighth Ann. Rept., p. 53. 

Oriskany: Cumberland, Mel.; New York; Cayuga, Canada.West. 

1892. 0!}rtina rostrata. Clarke, Am. Jour. Sci., 3d ser., vol. 44, p. 414. 

Oriskatiy siliceous limestone: Becraft Mountain, Columbia County, N.Y. 

1893. O!Jrtina heteroclita var. rnultiplicata. Whldborne, Devonian fauna of the south of England, vol. 2, pt. 3, p. 112, 

pl. 12, :figs 13-13a. · 

Cuboides zone: Lummaton and Woolborough, Devonshire, England. 

1895. Cyrtina rostrata. Hall and Clarke, Paleontology of New York, vol. 8, pt. 2, pl. 25, figs. 1-8; pl. 28, fig. 6. 

Oriskany sandstone: Albany County, N.Y.; Cumberland, Mel. 

1897. Cyrtina rostrata. Schuchert, U.S. Geol. Survey Bull. 87, p. 199. 

Oriskany and Corniferous: Albany County, N.Y.; Cumberland, Mel.; Cayuga, Ontario. 

1900. Cyrtina rostrata. Schuchert, Geol. Soc. America Bull., vol. i1, pp. 304, 306, 308, 314, 324. 

"Trilobite beds": Trilobite Ridge, Port Jervis, N.Y. 

Oriskany: Becraft Mountain, N.Y.; Oneida and North Cayuga townships, Canada West; Cumberland, Md. 

:1.900. Cyrtina varia. Clarke, New York State Mus. Mem., vol. 3, No.3, p. 49 (pars), pl. 6, figs. 15-22. 

Oriskany siliceous limestone: Becraft Mountain, Columbia County, N.Y. 

1903. Cyrtina rostrata. Schuchert, U. S. Nat. Mus. Proc., vol. 26, p. 422. 

Becraft limestone: Cherry Run, W.Va. 

1903. Cyrtina rostrata. Weller, Paleo:Q.tology of New Jersey, vol. 3, pp. 94, 95, 330, pl. 45, figs. 19-22. 

Dalmanites dentatus (or lowest) zone of Oriskany ("Trilobite beds"): Trilobite Ridge, Nearpass section; and 

Wallpack Ridge at Peters Valley, N.J. 

1903. Cyrtina varia. Weller, idem, pp. 98, 99, 100, 355, pl. 48, figs. 13-16. 

Orbiculoidea jervensis (or middle) zone of Oriskany: Second wagon road across Wallpack Ridge, about 5 miles 

from New York State line. 

Spirijer ?nurchisoni (or upper) zone of Oriskany: Werden farm, Nearpass section; and from three-fourths of a 

mile west of Layton, N.J. 

1903. Cyrtina rostrata. Van Ingen and Clarke, New York State Mus. Bull. 69, pp. 1203, 1207. 

Oriskany siliceous limestone: .Glenerie, N.Y. 

1905. Oyrtina rostrata. Clarke, New York State Mus. Bull. 80, p. 145. 

Grande Greve limestones: North shore of Gaspe Bay, Quebec. 

1905. Cyrtina rostrata. Shimer, idem, pp. 185, 227, 253, 263. . 

Dalmanites dentatus (or lowest) zone of Oriskany: Trilobite Ridge, Orange County, N.Y. 

1905. Oyrtina rostrata. Williams and Kindle, U. S. Geol. Survey Bull. 244, p. 48. 

Lewistown limestone: One-half mile north of Covington (1382A', p. 40). 

Coarse sandstone (Oriskany): One-half mile west of Clifton .Forge (1384A, p. 43); both in Alleghany County, Va. 

Width more than twice tne length; outline (of brachial valve) broadly trapezoidal to tri- · 

angular; greatest width at or just in front of the hinge. Pedicle valve pyramidal; cardinal 

area as high as or higher than the length of the valve, about normal to the plane of the margin, • 

and ve~-y slightly arcuate, not retrorse; apex pointed. Median septum extending not more than 

halfway to the front. Plications strongly elevated on the internal mold as ·well as on the surface; seven or eight each side of the middle, the end ones rather weak. ·Fold and sinus prom-
• 

78 FAUNA OF THE CHAPMAN SANDSTONE OF MAINE. 

inent, simple, not distinctly grooved or "mesicostulate." Surface marked by numerous imbricating lamellre, and under a lens there may be observed in places extremely :fine fiber-like 

radiating lines. 

Locality: Chapman sandstone, west side of Edmunds Hill and Presque Isle Stream, Chapman Township, Aroostook County, Maine. 

U. S. National Museum, catalogue Nos. 59727, 59728. 

Oomparisons.-The term 0. rostrata I-Iall may be applied to a series of shells having in 

common the following characters: Form transversely elongate; surface plications strong; ribs 

rather abundant, strong, and not prominently increasing in width toward the middle; fold 

strongly elevated and sinus strongly impressed. The ribs are also prominent on the internal· 

molds as well as externally in both the pedicle and the brachial v!}.lves. The transverse elongation makes the width two or more times the length, giving the b~achial valves a pennate appearance. This transverse elongation is less conspicuous in the pedicle valve than in the brachial 

valve. 

Such transversely elongated Cyrtinas with a large number of strong, narrow ribs have been 

found, without any known exception, to have the cardinal area high, slightly arcuate or plane, 

approximately normal to the margiri or occasionally retrorse, but never strongly arched, and 

the umbo in the pedicle valve not gibhous. 

From 0. hamiltonensis the shells may be distinguished by the wide form and prominent 

erect area; and though both have commonly the same number of plications ·(six to eight, nine, 

or ten each side of the middle), 0. hamiltonensis frequently has less than six, while in 0. rostrata 

there are never less than six and the prevailing number is about eight or nine. The plications 

are also a little stronger in 0. rostrata than in 0. hamiltonensis. 

In the European 0. heteroclita the normal .ornamentation is of the 0. dalmani type, with 

ribs more or less low, increasing markedly in width toward the middle, rather few in number, · 

and having the outline not transversely elongate. 

' A wide, strongly plicate Cyrtina, of almost typical 0. rostrata aspect, occurs in the Hamilton 

at Delphi, N.Y./ along with normal and variant Oyrtina hamiltonensis and 0. hamiltonensis var .. 

recta. A couple of similar specimens have been observed in a large suite of variants of 0. 

heteroclita in my collection from Gerolstein, in the Eifel. These indicate the extension of the 

rostrata type of Oyrtina into the Meso-Devonian in New York and in the Eifel as well as in 

Devonshire, Spain, and Russia. The European Meso-Devonian and Neo-Devonian forms from 

the Eifelian of Torquay and from the Cuboides zone at Lummaton, are commonly known as 

Oyrtina heteroclita var. multiplicata .Davidson. The retrorse cardinal area is a conspicuous 

feature in some British specimens, but is also occasionally present in 0. rostrata in the Oriskany 

of Maryland and apparently in one of the Gerolstein specimens. The area is not retrorse in the 

Chapman fo!ms. · 

The Oyrtina varia of Clarke has the form of 0. rostrata, but the name may be used in varietal 

rank and applied to those specimens in which there is a median groove extending along the fold 

of the brachial valve, and a narrow rib or flattening in the bottom of the sinus in the pedicle 

valve. Such "mesicostulate" forms of 0. rostrata have not been· observed or recorded above 

the Oriskany, although one Gerolstein specimen· shows (only, however, at the extreme front 

margin) a little groove in the fold. The variety varia Clarke bears a relation to 0. rostrata 

similar to that of var. demarlii Bouchard 2 to 0. heteroclita. 

In large lots of 0. hamiltonensis and 0. heteroclita may be found occasional specimens of 

the 0. rostrata type with the rather large number of strong ribs and the outline transversely 

elongate. Such specimens, whether from the Oriskany of Maryland, the Hamilton of New 

York, the Stringocephalus zone of the Eifel, or the Cuboides zone of Devonshire, have the 

cardinal area high, erect, rarely retrorse, and never strongly overhanging . 

1 Collections of Cornell University Museum; No. 1457 on specimens, No. 1454 on labels. 

2 See Davidson, Thomas, British Devonian Brachiopoda, p. 50, pl. 9, figs. 15-17, 1864. Whidborne, G. F., Devonian fauna of the South <if 

. England, vol. 2, pt. 3, p. 113, pl. 12, fig. 10, 1893. 
MOLL USCOIDEA. 79 

In the ·I-I elder berg, Oriskany, and Onondaga (' 'Cornif erous '') faunas 0. rostrata maintains 

a characteristic fonn, distinct from the other Cyrtinas occurring in the sa1ne formations, thus 

justifying the use of. a separate name of specific rank for the specimens of this type in this series 

of rocks. In these formations 0. rostrata is an important and in the Oriskany by far the dominant type of Cyrtina, and the common variants are variants fron1 the 0. rostrata typ~. Some 

pAleontologists would unite 0. rostra~ and 0. hamiltonensis, because in the Middle Devonian 0. 

rost?Yttct occurs as a variant of 0. hamiltonensis and not as a distinct species, but inasmuch as 0. 

r·ostra,ta, in its typical early occurrence in the Helderberg to Onondaga('' Corniferous ")is a species 

very distinct from the other Cyrtinas occurring in these formations, where it is a persistent and 

m.ore or less constant type, I am disposed to consider 0. rostrata as a separate species, distinct 

from 0. ha,miltonensis and 0. heteroclita, and to believe that in the great variability of the latter 

species there occasionally branches off a form re·calling the characters of the earlier type 

0. ?'Ostrata. 

0. dalmani differs from th~ type of Oyrtina hamiltorwnsis in having the lateral plications 

fewer in number and increasing rapidly in width and strength toward the middle. 0. rostrata 

differs from 0. hamiltonensis, 0. dalmani, and 0. heteroclita in being very wide and pennate and in 

having the maximum number of plications, which are stronger than in 0. heteroclita. 

In Europe the name Oyrtina ·heteroclita De France, 1824, is given to· a great variety of 

Cyrtinas, the dominant expression of which is apparently that of the 0. dalmani type, with 

plications rather few in number, increasing markedly in strength and width toward the middle; 

median fold simple, not wider than the two bounding ribs on either side; outline o~ the brachial 

valve quadrangular or semicircular, not transvers~ly elongated. A better knowledge of De 

France's originul types is necessary before the synonymy of the 0~ heteroclita-hamiltonensis 

forms can be unraveled. 

CYRTINA HETEROCLITA var. ALPHA var. nov. 

Plate V, :figure 15. 

This variety is distinguished by its well-defined obscurity or absence of radial ribbing. 

The surface is either actually smooth without ribs, or the ribs are present as extremely indistinct undulations. The internal molds are practically smooth. Fold and sinus are developed 

but are rather low. The outline is quadrate, not transversely extended. The cardinal area is 

arched and typically directed more or less posteriorly. The median septum in the pedicle valve 

is thick and long, extending three-quar~ers of the way to the front. The shell is normal in 

outline or only very slightly distorted. Vascular pits are deyeloped· in the posterior half on 

the umbonal slopes beginning alongside the sinus. On the surface, as represented in external · 

mold, there are six or seven very obscure radial undulations; the interior of the pedicle valve is 

practically without radial ribbing. The width is less than twice the length. The ribs increase 

sli~htly in width and in prominence toward the center, though not so markedly as in Oyrtina 

dalmani or in the normal 0. heter.oclita type. . . 

Locality: Oyrtina heteroclita var. alpha occurs in the Chapman sandstone in the west side of 

Edmunds :Hill, Chapmnn Township, Aroostook County~ Maine. It is found in apparently the 

same beds with Oyrtina rostrata, from which it is easily distinguished by its squarer outline 

and.obscure plications. 

U.S. National Museum, catalogue No. 59729. 

Oomparisons.-This variety in its typical expression is very distinct from Oyrtina heteroclita, 

but a suite of Eifelian specimens from Gerolstein shows a series· of nearly all the transitional 

forms. The same variation toward obsolescent ornamentation is occasionally encountered i.n 

Oy'rtina hamiltonensis, from the Hamilton formation of New ~ork. In the Ithaca shale member 

of the Portage formation a Cyrtina of this nearly smooth type is a very common form. 

A smooth Cyrtina from the Dundee ("Corniferous") limestone of Michigan and the 

Onondaga limestone of New York has been described by Hall as Oyrtina biplicata. 1 It appears 

• Hall, Jruncs, New York State Cab. Nat. Hist. Tenth Ann. Rept., p. 165, 1857; Paleontology of New York, vol. 4, p. 266, pl. 27, figs. 5-10, 1867! 

vol. 8, pt. 2, pl. 28, figs. 7-10, 1895. C'yrtina biplicata also occurs in the Eifel at Gerolstein. 
80 FAUNA OF THE CHAPMAN SANDSTONE OF MAINE. 

to be a species with persistent and distinctive characters, which include a transversely elongated 

outline, smooth surface, a deep groove each side of the median fold, simple fold and sinus, and 

absence of plications. Oyrtina biplicata differs from the nearly smooth form 0. heteroclita var. 

alpha in the total and constant absence of ribbing and in its broad outline. 

Genus SPIRIFER Sowerby, 1815. 

SPrRIFER coNCINNUS Hall. 

Plate I, figures 6, 7; Plate II, figures 1, 4, 11, 12; Plate III, figure 5; Plate IV, figures 5, 6; Plate V, figures 16, 17. 

1857. Spirijer _concinna. Hall, New York State Cab. Nat. Hist. Tenth Ann. Rept., p. 60, figs. 

Shaly limestone and upper Pentamerus limestones of the Lower Helderberg; Albany and Schoharie counties, 

Hudson, etc., N.Y. 

1859. Spirijera concinna. Hall, Paleontology of New York, vol. 3, pp. 200, 494, pl. 25, fig. 2; pl. 28, fig. 7. 

Shaly limestone:1 Helderberg Mountains and Hudson, N.Y. 

Upper Pentamerus limestone; Schoharie and Helderberg Mountains, N.Y. 

1876. Spirifer concinnus. Barrett, Lyceum Nat. Hist. New York City Annals, vol. 11, p. 296. 

"Trilobite beds"; Bennett's quarry, Port Jervis, N.Y. 

1882. Spirifer concinnus. I. C. White, Pennsylvania Second Geol. Survey Rept. G6, p. 132. 

Stormville shaly calcareo-siliceous beds ["Trilobite beds"]: Monroe.County, Pa. 

1883. Spirijer concinna. Hall, New York State Geologist Second Ann. Repi., pl. 55, figs. 1, 2. 

Lower Helderberg group: Helderberg Mountains, N.Y. 

1890. Spirijer concinnus. Deeks, Canadian Rec. Sci., vol. 4, No.2, p. 108. 

Lower Helderberg: St. Helens Island, Montreal. 

1893. Spirijer concinnus. Hall and Clarke, Paleontology of New York, vol. 8, pt. 2, pp. 24, 27, 38, pl. 30, figs. 1, 2. 

Lower Helderberg group: Helderberg Mountains; N.Y. 

1896. Spirijera concinna. Ami, Canada Geol. Survey Ann. Rept., new ser., vol. 7 (for 1894), p. 155J. 

Lower Helderberg limestone: St. Helens Island, Montreal. . 

1899. Spirijer concinnus. Prosser, 2 New York State Geologist Seventeenth Ann. Rept., pp. 341, 351. 

Becraft limestone: Countryma:r;t Hill and Clarksville-Oniskethau Creek sections, Helderberg Mountains, Albany 

County, N.Y. 

1900. Spirijer concinnus. Schuchm·t, Geol. Soc. America Bull., vol. 11, p. 284. 

New Scotland and Becraft limestones: New York, Maryland, and Virginia. 

1900. Spirifer cf. concinnus. Williams, U. S. Geol. Survey Bull. 165, pp. 79, 80. 

Chapman sandstone: Chapman, Aroostook County, Maine. 

1901. Spirijer concinnus. Prosser, New York State Geologist Eight~enth Ann. Rept. (for 1898), p. 62. 

Becraft limestone: Near Gallupville, Albany County, N.Y. 

1901. Spirijer concinnus. Schuchert, Am. Geologist, vol. 27, p. 249. 

· Becraft limestone: St. Helens Island,· Montreal, Canada. 

??1901. Spirifer allied to S. arenosus. Schuchert, idem, p. 249. 

Becraft(?) or Middle Devonian(?) limestone: St. Helens Island, Montreal, Canada. 

1903. Spirijer concinnus. Schuchert, U. S. Nat. Mus. Proc., vol. 26, p. 422. 

Becraft limestone: Cherry Run, W.Va. 

not 1903. Spirijer concinnus. 3 Weller, Paleontology of New Jersey, vol. 3, pp. 83, 289, pl. 30, fig. 3. 

Uppermost Coeymans: Near Hainesville, N.J. 

1903. Spirijer concinnus. Grabau, New York State Mus. Bull. 69, pp. 1060, 1067, 1068. 

Becraft and Port Ewen beds: Becraft Mountain, Columbia County, N. Y. 

1903. Spirijer concinnus. Van Ingen and Clark, idem, pp. 1188, 1191, 1193, 1197, 1207. 

Lowest Coeymans (?), 4 upper New Scotland, middle and upper Becraft, and lower Port Ewen limestones: Becraft 

Mountains, Columbia County, N.Y. 

cf. 1904. Spirijer excavatus (?not Kayser). Drevermann, Palaeontographica, vol. 50, p. 254, figs. 8-10. 

Siegen graywacke: Seifen, near Dim·dorf, Rhenish Prussia. 

1905. Spirijer concinnus. Shimer, New York State Mus. Bull. 80, pp. 183, 232, 233,249,265 (in part). 

Becraft limestone:· Trilobite Mountain, N. Y. 

1 Hall (op. cit., p. 494) reported that among enormous collections of shaly limestone[New Scotland] fossils made in Albany County between 

1843 and 1857 only a single specimen of S. concinnus was found. At the time the volume cited was written only two specimens ";.ere known at the 

New Scotland horizon, thesecond specimen being presumably from Hudson, N.Y. This species is abundant and apparently very widespread in 

the Becraft limestone and upper part of the Helderberg group, of which it is a diagnostic fossil. ~ 

2 Dr. C. E. Smith has identified this species from the New Scotland limestone of the Indian Ladder section of Countryman Hill. 

a The ribs are too few (only eight on each side) and too coarse for this species. See text, p. 82. . 

4 The citation of Spirifer concinnus in the Coeymans, especially at its base, is to be taken with some doubt. 
MOLL USCOIDEA. 

1905. Spirijer conc:innus. Williftms.and Kindle, 1 U. S. Geol. Survey Bull. 244, p. 39. 

Lewistown limestone: Covington, Va. (localities 1382 B' and 1382 A). 

1907. Spirifer subcuspidatus late1:ncisus (not Scupin). Clarke, New York State Mus. Bull. 107, p. 254, figs. 

Lower Devonic: Presque Isle Stream, Chapman Plantation, Aroostook County, Maine. 

A plicated Spirifer of moderately sn1all size with rounded extremities, nonelongated outline, and 11 or 12 r~bs on each side of the sinus a~1d fold. Width less than twice the length, ratio 

varying fron1 1!:1 to 11-:1, comn1only about 1t:l. Hinge lh1e straight, commonly slightlJ 

shorter than the greatest width. I-Iinge extremities recta.ngular or rounded, rarely acute, never 

(in the Maine specimens) mucronate. Lateral and front margins arcuate. Pedicle valve 

gibbous, with a broad, tun1id umbo; beak incurved but elevated above the brachial valve .. 

Greatest depth of the pedicle valve over the hinge line.· Cardinal area well developed, strongly 

curved; delthyriun1 large, acute, its sides subtending an angle of less than 60° but more than 

45°. On the interior dentallamellre extend one-fourth to one-third the length from the beak. 

They are· situated generally 2 nearly un9.er the third sinus, each side of the large median sinus. 

'fhe muscular scars are not i1npressed. The brachial valve is nearly equal in co:nvexity to the 

pedicle valve; greatest depth slightly back of the middle; cardinal area appreciably curved, 

but much narrower than in the pedicle valve. Cardinal process simple. A median elevated 

line or very obscure septum extends about half the length of the brachial valve on the interior. Depth (with both valves in conjunction) varyi.ng from 0.75 to 1.1 times the length of 

the brachial valve. · 

'fhe surface is 1narked by 11 or 12 strongly elevated, rounded plications each side of the 

fold and sinus; the ~inus in the pedicle valve is angular in the bottom, rather deep, and without any median riblet. It is equal in width to about four lateral ribs .. · The fold in the 

brachial valve is strongly arched and broad topped; the surface is generally marked by a median 

groove which is occasionally indistinct, although in some specimens it is so well developed that 

it divides the median fold i.nto two strong plications. On only one of the many external molds 

of the Man1e specimens was the fi.ner surface ornamentation discernible. This consisted of concentric lamellre, strongly recurving on the brachial fold. The largest specimen observed was 17 

millimeters long and 26 millimeters wide. The average specime.ns are about three-fifths that 

size. The distinguishing features of this species are the small size, the rounded or square 

shoulders, and the number of plications (11 or 12, rarely as many as 14) on each side of the usually· 

simple sinus and fold. 

The specimens figured show some variations, which are noted in the following paragraphs. 

Plate I, figure 6. A brachial valve of average size from locality 1099 L, in which the dorsal 

tnedian septum shows more strongly ·than usual. 

Plate I, figure 7. Another brachial valve from the same locality, showing the groove in the 

·. fold common in Maine specimens. . 

Plate II, figure 1. A pedicle valve from Presque Isle Stream, of very large size but showing the usual outline, ornamentation, and the angular sinus without median riblet. 

Plate II, figure 4. A pedicle valve, from St. Helens Island, near Montreal, Canada. 

Plate II, figure 11. Cardinal aspect of an internal mold from Presque Isle Stream, with 

both valves in conjunction, showing the high, curved cardinal area and also the slight inequality 

in convexity of the two valves. . 

Plate II, figure 12. Cardinal aspect· of anot4er pedicle valve from Presque Isle Stream, 

showing high curved cn.rdinal area and the dentallamellre. This is the only specimen in our 

collection in which the dental lamellre occupy the first groove on each side of the sinus; usually 

t Those specimens are large (about 24 by 33 millimeters) and show 13 or 14 plications on each side. The ribs are narrow and low and the sinus is 

. not so deeply excavated as in the :Maine forms. In one of the specimens (labeled fig. 204, Feb. 3, 1899; 1382 B') there are two very obscure ribs in 

the sinus, ono on oach sido. Those originate as branches from the ribs bounding the sinus, exactly as in the early stages of S. arenosU,S; but in the 

present spocimon tho sinus continuos well pronatmced, no further ribs are developed, and the two ribs which do appear are so obsolescent as to be 

discernible with difficulty. This specimen suggests the close phylogenetic relationship to Spirifer arenosU,S, not only because the ribs which bound 

tho sinus sond off br!Ulch ribs into the sinus, but also because of the large size of the shell, the low and numerous ribs, and the shallower sinus, 

which aro foaturos moro or loss uncommon in Spirifer concinnus. . 

2 Their position in the Maino forms is variable. In one or two specimens the lamell!e are under the first lateral sinus. 

50245°-No. 89-16--6 
82 FAUNA OF THE CHAPMAN SANDSTONE OF MAI~E. 

they are situated at about the third groove on each side of the sinus. Clarke describes and figures his Presque Isle Stream specimens, which he identified with Spirifer subcuspiclatus var. 

lateincisus Scupin, as having the lamellre in the first lateral groove on each side the sinus. 

· Locality: Chapman sandstone, Edmunds Hill, Presque Isle Stream, and 2! miles west 

of Presque Isle Stream, Chapman Township, Aroostook County, Maine. 

U.S. National Museum, catalogue Nos. 59730 to 59734. 

Comparison with the typical New York specimens.-There are a few .minor points of distinction between the· New York and Maine specimens. The· former are described by Hall as 

having 12 to 14 plications on each side; in the Maine specimens there are only 11 or 12. Many 

New York specimens examined by us from several localities, however, have the same number of 

ribs as· the Maine forms. · 

, In specimens from Becraft Mountain, N. Y., Shimer 1 reports only eight or nine-in one 

specimen probably ten-plications on each side~ The Trilobite ·Mountain specimens average 

eight to ten plications on each side,· and some very large specimens (27 millimeters long and 

31 millimeters wide) having 12 ribs on each side are recorded. Weller's specimens from the 

Coeymans-New Scotland transition beds have only eight ribs on a side. These figures indicate 

that average specimens from the Becraft limestone of Becraft Mountain and Trilobite Mountain, N.Y., having an approximate length of 16 millimeters and. width of 23 millimeters, have 

only eight to ten plications on each side of the middle. The :Maine specimens, though smaller 

than these, have commonly 11 or 12 plications on each side. One or two have as many as 13 or 

possibly 14, and these agree with the species as described by Hall and as generally distributed 

in the Becraft of New York. The shells called Spirifer concinnus, fr01n !Trilobite and Becraft 

Mountains, and possibly New Jersey, may therefore represent a distinct·species or more probably 

are to be identified with Spirifer cyclopterus. 

The strength of the plications in the New York forms is variable, but commonly they are 

pronounced, rather than "little elevated," as.stated by Hall. The strength of the fold and sinus 

is also variable in the New York specimens, and the median sinus is generally shallower than 

in the specimens from Maine. A faint riblet was observed in the median sinus of one or two 

New York shells, but no such riblet has yet been observed in the Maine specimens, though they 

have commonly a grooved fold in the brachial valve, a· feature very rare in theN ew York forms. 

The cardinal extremities in the Maine specimens are rectangular or rounded; the form with 

salient cardinal extremities occasionally found in New York has not been observed in Maine. 

In his paper on the Silurian and Lower Devonian faunas of Maryland 2 Schuchert, without 

description, lists a fossil from the Maryland Oriskany as" Spirijer concinnoides nov." As I am 

unacquainted with the fossil thus designated, no comparisons between the Chapman modifications of S. concinnus just described and the Maryland forms can be made at present. 

· Comparison with related species.-The Chapman forms here called Spirifer concinnus are 

remarkably similar to some shells identified with the Spirifer excavatus Kayser, 3 from the lowest 

Devonian of Germany. Scupin 4 removes from Kayser's species the specimens figured by 

Kayser in his Plate XXII, figure 7; Plate XXV, figure 26 ( =S. hystericus); Plate L\::II, 

figure 9, and probably Plate XXIII, figure 6, and restricts the name to shells having only eight 

or nine plications on each side; he regards Kayser's Plate XXII, figure 11, as the type of the 

species and figures Kayser's original specimen. In both Kayser's and Scupin's figures of this 

specimen there are 11 or 12 plications on each side, not eight or nine, as mentioned in Scupin's 

text. This type is a large specimen; the fold is very deeply divided, the ribs angular, and the 

interspaces broad. This form is very similar to the Spirifer sp. indet. Weller,5 from the Kanouse 

sands tone · (so-called "Newfoundland grit") of New Jersey. 

These spirifers with angular ribs and very deeply and broadly divided median fold have 

nothing in common with typical Spir~fer concinnus arid but little in common with the Chapman 

1 New York State Mus. Bull. 80, p. 249, 1905. 

2 U. S. Nat. Mus. Proc., vol. 26, pp. 413-424, 1903. 

a Consult Kayser, Emanuel, Die fauna der iUtesten Devon-Ablagerungen des Harzes, p. 17, pl. 22, figs. 7-9, 11; pl. 23, fig. 6; pl. 25, figs. 22, 25, 

26, 1878. 

4 Spiriferen Deutschlands, p. 24, pl. 2, fig. 8, 1900. 

5 Paleontology of New Jersey, vol. 3, p. 376, pl. 52, fig. 4, 1903. 
MOLL USCOIDEA. 83 

sandstone forms of Spir~fer concinnus. The latter are more nearly comparable with the sn1aller 

shells having rounded ribs, narrower interspaces, and fold not so broadly cleft, represented by 

'the fossils collected by Drevermann from the Siegen graywacke at Seifen and elsewhere in· the 

Rhenish province and described and figured by him as Spirifer excavatus. 1 . Indeed, Drevermann's figures 8 and 9 look as if they might have been drawn from Chapman specimens; hjs 

figure 10 shows fewer ribs. It is difficult with our present knowledge to satisfactorily separate · 

these Siegen graywacke fo~sils specifically from the Chapman forms, but it may be questioned 

whether these fossils can be strictly identified with Kayser's Hercynian (Lower Coblenzian) 

S. excavatus, which is larger and has a more broadly cleft fold and angular ribs with wider 

in terspaces. 

Although Kayser's forms agree with the Chapman specimens in outline, convexity, and 

muscular n1arkings, and in having 11 or 12 ribs each side of the fold, which is deeply cleft, the 

persistently more deeply cleft fold in the brachial valve, as well as some minor characters of the 

original IIercynian Spirifer excavatus of Kayser and Scupiri show little direct relationship with 

the New York typical Spirifer concinnus. In Kayser'~ Hercynian species the ribs are n1ore 

angular and have wider interspaces than in the Chapman forms of S. concinnus. It is also larger 

and, though it agrees with the Maine shell in the presence of a cleft fold, that character is very 

persistent and very n1uch better developed in the German species. than in the Chapman fossils. 

" S1Jirije:r carinatus Schnur and Spirifer nerei Barr.ande 2 alsb closely resemble Spirifer concinnus but generally have the fold carinate instead of rounded. In Spirifer nerei Barrande 

the utubones are usually more inflated than inS. concinnus. Finally, both S. carinatus Schnur 

and S. nerei Barrande are larger than S. concinnus-very much larger than the ordinary Chapman forms of that species-and also frequently have one or two more ribs on each side than the 

maxim un1 of· S 1Ji'rifer concinnus. 

These Chapman fossils have been identified by Clarke 3 with Spirifer subcuspidatus Schnur 

var. lateincisus Scupiu. 4 The German species, which occurs in the white sandstone of the 

Kahleberg and at other points in the Oberharz, in beds of the age of the Coble~ (Ems, or 

Middle Coblenzian) quartzite, is a larger and wider form than the Chapman Spirifer concinnus, 

and its cardinal extremities are. more acute. The height of the cardinal area in the Chapman 

.fossils is less, and the two valves are more nearly equal in convexity. There is, however, a very 

close similarity between the shells from Aroostook County, Maine, and those from the Harz 

Mountains,. Germany. 

Vwrio,tion of Spi1·ijer concinnus toward Spirifer arenosus.-In the beginning of its career 

as a species Spirifer concinnus seems to have been derived from some such form as Spirifer 

cyclopterus, fron1 which it differs only, aside from a few insignificant points, in having a few more 

ribs. Toward the end of its career Spirifer ·concinnus, a species with a simple fold and sinus, 

varies toward Spirifer arenosus, a species with a plicose fold and sinus. Hall noted this feature in S. concinnus when he stated 5 that in ''many specimens there are faint indications of a 

fold on each side of the mesial sinus and of several similar ones upon the corresponding mesial 

elevation; this character, however., is not constant in the specimens examined." Such a form is 

figured by :Hall and Clarke. 6 

In some rocks at St. Helens Island, near Montreal, Canada, which contain Helderberg 

fossils, occurs a Spirifer which has been listed by Donald, Deeks, Ami, and Schuchert as '' Spiri- . 

fer allied to a1~enosus." In 'the words of Schuchert,7 "This is apparently the earliest form of 

S. arenosus type." rlowever, it is not that species, since when small it is much likeS. concinnus, 

but toward n1aturity the fold and sinus became plicated. Characteristic representatives of 

the species Spi1·ijer a1·enosus have been recognized in the breccias of St. rielens Island,8 proving 

' Palaeontogrnphica, vol. 50, p. 254, figs. 8-10, 1904. 2 Soo Scupin, Hans, Die Spirifcrcn Deutschlands: Palaeont. Abh. (Dames & Koken, Jena), vol. 8, Heft 3, pp: 26 and 32, 1900, for references, 

description, and figures of these species. · 

s New York State Mus. Bull. 107, p. 254, figs., 1907. 

~ Scupin, Hans, op. cit., p. 223, pl. 24, figs. 13, 14a-c. 

o Paleontology of New York, vol. 3, p. 200, 1859. 

o Idem, vol. 8, pt. 2, pl. 30, 1893. · 

7 Am. Geologist, vol. 27, No.4, p. 2·19, April, 1901. 

a Williams, H. S., Roy. Soc. Canada Pro,c. and 'l'rans., 3d ser., vol. 3, p. 221, 1910. 
84 FAUNA OF THE CHAPMAN SANDSTONE OF MAINE. 

conclusively that the Oriskany was represented there. The specimen from St. Helens Island 

figured in the present work (Pl. II, fig. 4) plainly shows the similarity in configuration to S. 

concinnus. "In S. arenosus of the Oriskanian, the horizon for this species (S. arenosus)," · 

continues Schuchert, ''the plication of the fold and sinus is not a recently ·acquired character, 

for it appears in the shell when quite sniall." This is true both in general and particularly in 

regard to 'the Maryland specimens; but specimens of Spirifer arenosus nearly an inch wide. 

from Union Springs, N. Y., are without plications on the fold. Plicose specimens of S. concinnus may be distinguished from small forms of S. arenosus chiefly by the more elevated plications and rounded shoulders.1 The type is similar to Spirifer grieri Hall/ from the American 

"Corniferous" limestone, and Spirifer winterii Kays.er. 3 

SPIRIFER ARENOSUS (Conrad). 

Plate I~, figures 15, 16, 19, 21; Plate III, figure 1; Plate V, figure 18. 

1839. Delthyris arenosa. Conrad, New York Geol. Survey Third Ann. Rept., p. 65. 

"Helderberg, in sa"ndstone." [Oriskany sandstone: Helderberg Mountains, N. Y.] 

1842. Delthyris arenaria. Vanuxem, Geology of New York, Rept. ThirdDist., p. 123, fig. 1; p. 124, fig. 5. 

OrisKany sandstone: Third district. (Madison County westward to Cayuga Lake), N. Y. 

1843. Delthyris arenaria. Mather, idem, Rept. First Dist., p. 342, fig. 1. · 

Oriskany sandstone: Hills east and west of Schoharie; various places in the Helderberg Mountains, in tho towns 

of Berne, Knox, and Bethlehem, and southward to Esopus Falls, N. Y. 

1843. Delthyris arenosa. Hall, idem, Rept. Fourth Dist., p. 148, fig. 1. 

Oriskany sandstone: New York. 

1858. Spirijer arenosa. Rogers, Geology of Pennsylvania, vol. 2, pt. 2, p. 826, fig. 650. 

Meridian formation (Oriskany): Pennsylvania. 

1859. Spirijer arenosus. Hall, Paleontology of New York, vol. 3, p. 425, pl. 98, figs. l-8; pl. 99, figs. 1-10; pl. 100, 

figs. 1-8. . 

Oriskany sandstone: Everywhere in New York, "being one of the most constant if not the most persistent fossil 

of the rock. In the same rockin Maryland, Virginia, and elsewhere." 

1863. Spirijer arenosa. Billings, Geology of Canada, p. 960, fig. 465 a, b. . 

Oriskany (sandstone): North Cayuga, Ontario (p. 361). 

Gaspe limestones, division 8: Whitehead, Cape Barry, and Perce Rock, Gaspe (pp. 393, 439). 

?1867. Spirifera unica. Hall, Paleontology of New York, vol. 4, p. 203, pl. 30, fig. 21; pl. 55, fig. 8. 

Corniferous limestone: Clarence Hollow, Erie'County, N. Y. 

c£.1868. Spirijer arenosus. Dawson, Acadian geology, p. 498 (1891 edition), 

"Oriskany" Nictaux iron ore; Nictaux, Nova Scotia. 

1874. Spirijerasuperba. Billings, Paleozoic fossils, vol. 2, pt.1, p. 47, pl. 3A, figs. 3, 3a, 3b (notS. superbus Eichwald). 

Gaspe limestone No. 8: Indian Cove, Gaspe. 

1876. Spirijer arenosus. Barrett, Lyceum Nat. Hist. New York City Annals, vol. 11, p. 297. 

Oriskany: Bennett's quarry, Port Jervis, N.Y. 

1878. Spirijer arenosus. Ashburner, Pennsylvania Second Geol. Survey Rept. F, p. 239. 

·Oriskany (Meridian) coarse sandstone: East Broad Top Railroad cut at Three Springs; on Royer and Sandy 

ridges near Orbisonia, Huntingdon County, Pa. · 

1882. Spirijer arenosus. I. C. White, Pennsylvania Second Geol. Survey Rept. G6, pp. 124, 247, 248. 

Oriskany (Stormville?) limy, cherty shales: One mi.le south of Carpenter's Point village, Pike County, Pa. 

1882. Spirijera arenosa. Stevenson, Pennsylvania Second Geol. Survey Rept. T2, pp. 86, 103-104, 132, 149. 

Lower Helderberg-Oriskany transition (siliceous limestone): Wills Creek, near Hyndman, Bedford County, Pa. 

Oriskany (hard blue-gray grits): Wills Creek, above preceding locality, on Exline road, King Township, and at 

Bedford Springs, Bedford County, Pa. , 

1883. Spirijera arenosa. Hall, New York State Geologist Second Ann. Rept., pl. 55, figs. 3-7. 

Oriskany: Eastern New York and Cumberland, Md. 

1883. Spirijer superba. Ells, Canada Geol. Survey Rept. Progress for 1880-1882, p. 14DD. 

Upper Gaspe limestone (Oriskany): Indian Cove, the Blowhole, Grande Greve, and Little Gaspe, Gaspe Bay, 

QueBec. 

1 Williams, H. S., op. cit., pp. 221, 234. 

2 Paleontology of New York, vol. 4, p. 194, pl. 27, fig. 29; pl. 28, figs. 17-23, 1867. See Schuchert, Charles, U.S. Geol. Survey Bull. 87, p. 392, 

1897, for additional references. 8 Deutsch. geol. Gesell. Zeitschr., 1881, p. 331, pl. 19, fig. 1; occurs at Gerolstein, in the Eifel. Compare also Spirifer bischofi (A. Roemer's sp.) 

pars, figured by Drevermann in Palaeontographica, vol. 50, pl. 29, figs.l5-17, 1904. Drevermann's fossils are from the Siegen graywacke of Seifen,' 

etc., in the Westerwald. 
MOLL USCOIDEA. 85 

1883. Spirijer arerwsa. I. C. White, Pennsylvania Second Geol. Survey Rept. G7, pp. 86, 297, 305, 310, 329. 

Oriskany: J_,ittle Fishing Creek, Columbia County (cherty sandstone); Grove Bros. tunnel, Cooper Township, 

Montour County (chert); Mahoning Township, Montour County (sandy, limy chert); Chillisquaque Creek and 

Lime Ridge, J_,iberty Township, Montour County (blackish cherty beds); Delaware T<;>wnship, Northumberland County (cherty sandstone). · 

1883. Spir'ifera arenosa. I. C. White, idem, p. 346. 

Oriskany: Near milepost 135, Northern Central Railway, Upper Augusta Township (limy, cherty beds), and 

]~ower Mahanoy Township, Northumberland County, Pa. · 

1884. Spirijer arenosus. Ewing, Pennsylvania Second Geol. Survey Rept: T4, p. 431. 

Oriskany (coarse sand cemented with ilme carbonatef Alexander quarry, between Julian and Unionville, 

Center County, Pa. 

1885. Spirijera arenosa. I. C. \Vhite, Pennsylvania Second Geol. Survey Rept. T3, pp. 119, 259. 

Oriskaily sandstone: Mapleton and Huntingdon car works, Oneida Township, Huntingdon County, Pa. 

1885. Spirijera s1tperba and arenosa (?). Ells, Canada Geol. Survey Rept. Progress for 1882-1884, p. 24E 

Gaspe limestone No. 8: Grande Greve, Gaspe Bay. 

1899. Spirijera billingsana. Miller, North American Geology and Paleontology, p. 372 (nom. nov. proposed for " 

S. superba Billings, preoccupied). 

Gaspe limestone No. 8: Gaspe. .. 

1889. Spirijera arenosa. Schuchert, New York State Geologist Eiehth Ann. Rept. (for 1888), p. 53. 

Oriskany: Cayuga, Ontario; Cumberland, Md. 

1889. Spirijera arenosa. Simpson, Pennsylvania Second Geol. Survey Rept. 03, pp. 208-209. 

Oriskany sandstone: Sandy Ridge and Royers Ridge, Orbisonia, Huntingdon County, Pa. 

1892. Spirije'r arenosus. Clarke, Am. Jour. Sci., 3d ser., vol. 44, p. 413. · 

Oriskany siliceous limestone: Becraft Mountain, Columbia County, N.Y. · 

1893. Spirijer arenosus. Hall and Clarke, Paleontology of New York, vol. 8, pt. 2, pp. 24, 27, 37, pl. 29, figs. 1-4; 

pl. 30, figs. 3-8. -

Oriskany: Eastern.Ne'X York; Cumberland, ·Md. 

?1893. Spirijer unicus. Hall and Clarke, idem, pl. 30, fig. 8. 

Upper Helderberg limestone: Clarence Hollow, Erie County, N. Y. 

cf. 1895. Spirijera arenosa. Ami, Canada Geol. Survey Ann. Rept., new ser., vol. 6, p. 15Q. 

Nictau beds (Oriskany): Nictau, Nova Scotia. 

1897. Spirijer arenosus. Schuchert, U. S. Geol. Survey Bull. 87, p. 382. . 

Oriskany and Corniferous: Schoharie, Clarence Hollow, etc., N.Y.; Cumberland, Mel.; Virginia; Frankstown, 

Pa.; Cayuga, Ontario. · 

1899. Spirijer arenosus. P1·osser, New York State Geologist Seventeenth Aim. Rept. (for 1897), p. 341. 

Oriskany sandstone: Countryman Hill, Helderberg Mountains, N.Y. 

1900. Spirijer arenosus. Schuchert, Geol. Soc. America Bull., vol. 11, pp. 315-316. 

·"Monterey" formation (Oriskany): Cumberland, Md . 

. "Oriskany": North Branch of Potomac River at Keyser, Mineral County; Moosefield, Hardy County; North 

Fork of South Branch of Potomac River, Pendleton County, .W.Va.; Rock Enon Springs and 6 miles north~ 

west of Winchester, Frederick County, Va. 

:1.900. Spirijer arenosus. Clarke, New York State 1\fus. 1\fem., vol. 3, No. 3, pp. 46, 74, 77_:._79. 

Oriskany siliceous limestone: Becraft Mountains, N. Y. 

Oriskany sandstone: Oriskany Falls, Oneida County, N. Y.; in quartzitic sandstone (?), Livoni~ salt shaft, 

Livingston County, N.Y.; in siliceous limestone, Glenerie, N.Y.; in quartzitic limestone, West Mountain, 

Schoharie, N.Y. 

1901. Spirijer arenosus. Prosser, New York State Geologist'Eighteenth Ann .. Rept., p. 59. 

Oriskany (dru·k-gray sandstone): Altamont section, Helderberg Mountains, Albany County, N.Y. 

1901. Spirijer arenosus. Prosser, Jour. Geology, vol. 9, p. 418. 

Oriskany: Alleghany County, Md. 

1903. Spirijer arenosus. Weller, Paleontology of New Jersey, vol. 3, pp. 100, 101, 353, pl. 48, fig. 5. 

Spi1'ijer rnurchisoni or upper zone of the Oriskany (siliceous limestones): Three-fourths of a mile west of Leighton 

and at Peters Valley, N.J. 

1903. Spirijer arenosus. Van Ingen and Clark, New York State Mus. Bull. 69, pp. 1203, 1207. 

Oriskany siliceous limestone: Glenerie, N.Y. 

1905. Spirijer arenosus. Harris, Guide to the Geology of Union Springs, p. 4, pl. 13, figs. 1, 2. 

Oriskany sandstone: Yawger's \Voods, Union Springs, Cayuga County, N.Y. 

1905. Spirijer arenosus. Clarke, New York State Mus. Bull. 80, pp. 140, 143, 145, 149. 

Grande Greve limestone: North shore of Gaspe Bay. · . 

Perce limestone: Perce Rock, Blowhole, and Barre Brook, Gaspe Bay. 

1905. Spirifer arenosus. Shimer, idem, pp. 229, 251, 265. d 

Spirijer rnurchisoni zone, or upper division 6£ the Oriskany (dense blue limestone): Trilobite Mountain, N.Y. 
86 FAUNA OF THE CHAPMAN SANDSTONE OF MAINE. 

1905. Spirijer arenosus. Williams and Kindle, U. S. Geol. Survey Bull. 244, pp. 32, 34, 39, 43, 48 .. 

Giles formation [in sandstone of Oriskany age] interbedded in chert: Ravine 1! miles above Hicksville, Bland 

County, Va. (as Spir~fer .sp., p: 32); Springs Hotel, W. Va.; Jackson River, below Covington, and one-half 

mile west of Clifton Forge, Alleghany County, Va. 

1905. Spirijer arenosus. Clarke, Ne'\V York State Mus. Bull. 82, p. 41. 

Oriskany granular quartzite: Tully quadrangle, N.Y. 

Oriskany sandstone: Yawger's Woods, near Union Springs, and at Oriskany Falls, N.Y. 

1910. Spirijer arenosus (Conrad). H. S. Williams, Roy. Soc. Canada Trans., 3d ser., vol. 3, sec. 4, P·. 221. 

St. Helens breccias, lot 1 (252.1): St. Helens Island, near Montreal, Canada. 

This species, though not present in the Chapman sandstone, is introduced here with illustrations, because its importance as a stratigraphic landmark makes its absence significant in a 

fauna which has species genetically related to. it and with which it is necessary to institute 

detailed comparison. A full synonymy is also given in order to show its geographic distribution. 

The Moose River sandstone, in which ·the species is abundant, is exposed in an adjoining county 

· in'Maine and indicates the probable areal continuity of the basins in which the two faunas· 

lived, thus requiring succession in time to explain the difference in fauna. 

The species Spirifer arenosus is too well known to warrant any detailed description here. 

It is of interest to note that this, the first species in the American faunas with plicated fold 

and sinus, has no close equivalent in the European faunas. It is true that the first similarly 

plicose Spirifers-S. bischofi A. Roemer 1 and S. daleidensis Steininger 2

-occur in t4e European 

Eo-Devonian at a horizon .(the Taunusian, Siegen graywacke, or zone of Spirifer primrevus) 

supposed to be the equivalent of the Oriskany; but these European species can not be compared very closely with S. arenosus, for they have a different outline and convexity and a 

stronger fold and sinus and can easily be recognized as distinct. The second species named 

above (Spirifer daleidensis) has bifurcating ribs. Some specimens with distant and bifurcating 

ribs, which appear to be identifiable with SlJirifer daleidensis, have been observed in the Maryland Oriskany from Hicksville, Bland County, Va. 3 The Kentucky "Corniferous" en shells 

doubtfully identified by N ettelroth/ with Spirifer divaricata Hall, are similar to if not actually 

identifiable with S1Jirijer daleidensis Steininger. 

Locality: Spirifer arenosu.s occurs in the Moose River sandstone in Somerset County, l\1aine. 

All the figured specimens are from Detroit, Maine (locality 1100 A), except that shown in Plate 

III, figure 1, which is from the Oriskany at Keyser, l\1ineral County, W.Va. 

U.S. National Museum, catalogue Nos. 59735, 59736. 

SPIRIFER ARENOSUS var. SIMPLEX nov. var. 

Plate III, figures 2-4, 7, 12. 

This variety, which does not occur in the Chapman fauna, differs from Spirifer arenosus 

in having in the median sinus a single strong rib with one weaker rib on each side. The shells 

are of medium size, rather elongate; ratio of length to breadth, 3: 5 or 3: 4, generally near 

the latter. Hinge line equals the greatest width of the shell; hinge extremities square or nearly 

so, slightly auriculate. Cardinal area fairly well developed; curved, not erect. Delthyrium 

over 60°, nearly 90°. The musculature is deeply impressed in the pedicle valve and is marked 

by a broad median groove, a continuation of the botton1 of the median sinus of the valve. 

The surface is ornamented with low, flattened or rounded plications, of which there are between 15 and 21 on eac~ side of the fold and sinus. The interspaces between the ribs are 

very narrow. The plications at the lateral extremities are rather faint. In the bottom of the 

sinus is a central rib generally broader than any other plication on the surface, and on each 

side of this central rib is a single narrow rib. Fold and sinus broad, moderately elevated, not 

sharply demarcated. Brachial valves, associated with the typical pedicle valves in the same 

1 Roemer, A., in Giebel, C. G., Die silurische Fauna des Unterharzes, p. 29, pl. 4, fig. 3, 1858. 

2 Steininger, Johann, Geognostische Beschreibung der Eifel, p. 71, 1853. For further references see Scupin, Hans, Die Spirifcren Deutschlands, 

pp. 277-2i9, etc. 

aU. S. Geol. Survey Bull. 244, p. 32, 1905 (Spirifer sp.). 

• Nettelroth, .Henry, Kentucky fossil shells, p. 113, pl. 12, figs: 5-11, 1889; not pl. 11, figs. 6-11. 
l 

MOLL USCOIDEA. 87 

beds, generally exhibit a subdivision of the central plicatio'n within an inch from the point 

of the beak, so that frmn there forward there are four plications on the median fold. In son1e 

large specimens a slight linear depression is seen on the n1esial plication of the brachial valve 

near the front; and in several specimens the left-hand division of the median pair of plications 

on the fold (right-hand one when the specimen is examined with umbo upward) is bifurcate, 

and at the front the plications are five in number, which makes the inside plication ·of the 

first division take pr01ninence in place of the sulcus between the divisions. 

The ornan1entation characteristic of the variety simplex occurs iri the young of .all.Spirifer 

arenosus, but in the variety it is n1aintained apparently t-hroughout life and certainly in shells 

having a larger size than specimens or' S. arenosus which have the normal five plications, or. 

even seven plications, in the sinus. 

" SzJirijer arenosus var. simplex n1ay therefore be considered as founded on specin1ens of 

SzJirijer arenosus in which the juvenile ornamentation in the sinus is n1aintained longer than 

nonnal-in other words retarded-and in which the normal adult ornamentation in the sinus 

of typical S. arenosus is not attained. 

In very young pedicle valves of Spirifer arenosus the sinus is simpJe and "flat in the bottom, 

and the bounding rib on each·side is strong. At about 7 millimeters fron1 the beak each bounding rib dichotomizes; the inner branch is a little lower and weaker than the. outer, so that it 

appears to develop within the sinus. At nearly the same stage that the bounding ribs dichotonlize (about 1 1nillimeter's growth later), the flat· bottom of the sinus also dichotomizes, 

producing two more low ribs within the sinus; and at some distance in front, a narrower rib let 

is developed 1 between the two median ribs in the sinus. There are now five ribs in the sinus~ 

in older for1ns each bordering rib again dichotomizes, producing seven ribs in the A 

sinus. The stages of development may be summarized as follows, the letters 

referring to the accompanying diagram (fig. 2): I .fa\ 

1. Median sinus (A) simple, flat-bottomed; each bounding rib (B) strong. Diagram, B (A) B. z ' 

2. Each bounding rib dichotomizes, the inner branch being a little weaker. Diagram, B 

(b1, A, b1), B. 3 

3. The flat bottom of the sinus (A) dichotomizes. Diagram, B (bt, at, at, bt), B. 4 

4. A narrow riblet is added between them by the forking of one of the two divisions of (A). " 

Diagram, B (bt, at, a, at, bt), B. (This is the stage figured in Pl. III, fig. 1.) 

5. The marginal ribs of the sinus (either B or bt) again dichotomize. Diagram, B (b2 , b1, at, a, _J au. h,j 

at, b 1, b2), 13. FIGURE 2.-S U r- The development of the plications in the sinus and fold of Spirifer arenosus race ornamentafurnishes an admirable illustration of the evolutional'laws of retardation and tion or Spirifer 

acceleration. Although phases 1 and 2 of the above series are developed rather arenosus. 

uniforn1ly with exceedingly rare exceptions, at the same stage in the shell, the phases after 2 

are each dev-eloped at different successive intervals in different shells, and indeed pha.se 4 is in 

1nany shells not dev-eloped at all. 

1'he exa1nple ofretardation 1nay be explained here in connection with the v-ariety simplex. 

In this variety only the second stage of development of the above table is reached at n1aturity; 

the fiat botton1 of the sinus does not divide but remains simple as a broad, slightly elevated 

flat rib in the bott01n of the sinus. This co.o.dition is maintained in the largest specimen observed 

for a length of 30 1nillimeters from the beak (Pl. III, fig. 4), and in another specimen (No. 

215, not figured) for 27 millimeters. This large size and the abundance of material including 

Sinaller sizes indicate .that the variety simzJlex, though possessing the ornamentation of the young 

of typical S. arenosus, is not an immature forn1 of the species but a variety. This interpretation is further corroborated by the fact that in normal forms of S. arenosus, as illustrated 

by the only speci1nen (Pl. III, fig. 1) in the large collection from Keyser examined in this 

study, the 'mature stage, or fourth stage, of the diagrammatic classification, is attained at a 

t '!'his narrow ribiet is tho rosul t of tho dichotomizing of the sinus, generally of tho.J.eft branch and apparently less frequently of the right branch . 

. Tho origin or tho filthriblet by tho1lichotomizingof the lett branch in the sinus is visible in the specimen figured in Plate III, figure l; in Hall's specimens (Paleontology of Now York, vol. 3, pl. 100, fig. 4b, pl. 98, fig. 3, 1859); and in a specimen in the Cornell University (Col. E. Jewett) collection, 

No. 82, from Cumberllllld, M:d. In tho specimen shown in Hall's plate 100, figure Sa, and in another Cornell University specimen from Cumber. 

laud, Md., tho median riblet dichotomizes from tho right branch in the sinus. 
88 FAUNA OF THE CHAPMAN SANDSTONE OF MAINE. 

distance of less than 15 millimeters from the. beak. In all the others referred to var. simplex 

only the second stage is reached at full maturity. Compariso:J?. with the variety 'simplex shows 

that Spirifer concinnus with the rudimentary plications represents stage 1 of the diagram 

(fig. 2)' so far as development of plications on the fold and sinus is concerned. · 

Locality: Keyser, Mineral County, W.Va. This variety is the dominant form of Spirifer 

arenosus and is very abundant. Only one normal specimen of S. arenosus, with the typical 

five plications in the sinus, was observed in a large collection from this locality. 

U. S. National Museum, catalogue No. 59737. · 

SPIRIFER CYCLOPTERUS Hall. 

Plate I, figures 1, 4, 5, 8, 9, 12, 16, 18, 19, .20; Plate II, figures 3, 5, 6, 7, 8, 10, 13, 14, 20; Plate IV, fig~res 1, 10. 

1857. Spirife:r cyclopte:ra. Hall, New York State Cab. Nat. Hist. Tenth Ann. Rept., p. 58. 

Lower Helderberg shaly limestone: Helderberg Mountains, Schoharie, Catskill,. Hudson etc.; N. Y. 

1859. Spirijer cyclopterus. Hall, Paleontology of New York, vol. 3, p. 199, pl. 25, fig. 1. 

Shaly limestone of Lower Helderberg group: Helderberg Mountains, Schoharie, Catskill, Hudson, etc., N. Y. 

1863. Spirifera cycloptera. Billings and Logan, Geology of Canada, p. 957, fig. 457. 

Lower Helderberg: Canada [locality not given]. 

?1874. Spirifera cyclopte:ra. Billings, Paleozoic fossils, vol. 2, pt. 1, p. 48, pl. 3A, figs. 4b, 4c (not 4 and 4a, which 

areS. murchisoni Castelnau). 

Gaspe limestone No.8: Grande Greve and Indian Cove, &aspe, and Split Rock, Perce, Quebec. 

1876. Spirifer cyclopte:rus. Barrett, Lyceum Nat. Hist. New York City Annals, vol. 11, pp. 295, 296. 

Delthyris shaly limestone and Trilobite beds: Bennett's quarry, Port Jervis, N.Y. 

1882. Bpirifer cyclopte:rus. I. C. White, Pennsylvania Second Geol. Survey Rept. G6, pp. 132, 134. 

"Trilobite beds" at top of Stormville shales: Delaware River at Carpenters Point, Pa. 

Stormville limestone (lower part of Lower Helderberg): New Jersey and Pennsylvania. 

1882. Spirifera cyclopte:ra. Stevenson, Pennsylvania Second Geol. Survey Rept. T2, pp. 156, 159. · 

Lower Helderberg limestone: Imlentown road, east of Lutheran Church, Bedford County, Pa.; .Martins Ridge, 

near Maryland State line, Bedford County, Pa. 

1883. Spirifera cyclopte:ra. Hall, New York State Geologist Second Ann. Rept., pl. 61, figs. 12-13. 

LowerHelderberg: Carlisle, N.Y. 

1883. Spirifera cyclopte:ra. Ells, Canada Geol. Survey Rept. Progress for 1880-1882, p. SDD. 

Lower Gaspe limestones: Upper part of Griffin Cove River ne~ peaks 'of Ruisseau de la Grande Carriere, Gaspe, 

Quebec. 

1886. Spirifer cyclopterus. Darton, Am. Jour. Sci., 3d ser., vol. 31, pp. 212. 214. 

Lower.Helderberg: Cornwall Station, Orange County, N.Y .. 

1890. Spirifer cyclopte:rus. Deeks, Canadian Rec. Sci., vol. 4, No. 2, p. 108. 

Lower Helderberg limestone [Becraft fossils]: St. ·Helens Island, Montreal. 

1893. Spirijer cyclopte:rus. Hall, Paleontology of New York, vol. 8, pt. 2, p. 36, pl. 36, figs. 12, 13. 

Lower Helderberg: Carlisle, N. Y. 

1896. Spirifera cycloptera. Ami, Canada Geol. Survey Ann. Rept., new ser., vol. 7, p. 156J. 

Lower Helderberg: St. Helens Island, Montreal, Canada. · 

1897. Spirifer cyclopterus. Schuchert, U. S. Geol. Survey Bull. 87, p. 387. 

Lower Helderberg and Oriskany: Helderberg Mountains, New York; Gaspe and New Brunswick, Canada. 

1898. Spirifer cyclopte:rus. Prosser, New York State Geologist Seventeenth Ann. Rept., pp. 340, 341, 350 .. 

New Scotland shaly limestone: Countryman Hill and Clarksville, N.Y. . 

Becraft limestone:· Countryman Hill; Helderberg Mountains, Albany County, N.Y. 

1899. Spirifer cyclopte:rus. Girty, U. S. Geol. Survey Nineteenth Ann. Rept., pt. 3, p. 565. 

Lower Helderberg: T. 1 S., R. 8 E., Atoka quadrangle, Indian Territory [Oklahoma]. 

1900. Spirifer cyclopterus. Williams, U.S. Geol. Survey Bull. 169, p. 80. 

Chapman sandstone: Chapman, Maine. 

1900. Spirifer cyclopte:rus. Schuchert, Geol. Soc. America Bull., vol. 11, pp. 285, 294. 

New Scotland and Becraft: New York, Maryland, Virginia, Tennessee, Indian Territory, Maine, New· 

Brunswick. 

Oriskany: Localities not cited. 

1900. Spirije:r cyclopter.us. Clarke, New York State Mus. Mem., vol. 3, No.3, p . .73. , 

Kingston (=Port Ewen) impure schistose limestone; near Kingston, Ulster County, along West Shore Railroad, 

one-half mile southeast of Rondout Creek, N.Y. 

1901. Spirifer cyclopterus. Prosser, New York StMe Geologist Eighteenth Ann. Rept. (for 1898), pp. 54, 58, 61. . 

New Scotland Shaly limestone: Indian Ladder section, Countryman Hill;· High Point, Altamont; and Knox, 

. Helderberg Mountains, Albany County, N. Y. · 
MOLL USCOIDEA. 

1903. Spirifer cyclopterus. Schuchert, U. S .. Nat. Mus. Proc., vol. 26, p. 422. 

Coeymans limestone: Devils Backbone, near Cumberland, Md. · . 

New Scotland limestone: Bridge 21, Baltimore & Ohio Railroad, near Keyser, Mineral County, W.Va. 

Becraft limestone: Cherry Run, W. Va. 

89 

Hl03. Spirifer cyclopterus. Weller, Paleontology of New Jersey, vol. 3, pp. 82, 84, 85, 87-90, 287, 314, pl. 30, fig. 2; 

pl..38, figs. 1-6. · · 

Basal Coeymans limestone: Top of Nearpass Quarry bluff. 

Lower Coeymans limestone: One~half rriile northeast of Peters Valley, in the hillside. 

Coeymans limestone: Below Flatbrookville. 

]~ower New Scotland cherty limestone: Back of quarry and limekiln of Mr. Sanford Nearpass. 

New Scotland shaly beds: One-half mile northeast of first crossroads over 'Vallpack Ridge below New York 

State line, one-half mile below Hainesville, and 1 mile below Peters Valley. 

Upper part of New Scotland shaly beds: Nearpass section. 

Becraft hard gray cherty limestone: Low ridge, back of Nearpass Quarry Bluff. 

All localities in northwestern New Jersey. 

cf. Ul03. Spirifer conCinnus (not Hall's species). Weller, idem, pp. 83, 289, pl. 30, fig. 3. 

Uppermost Coeymans: Near Hainesville, N. J. 

1903. Spin'jer cyclopterus. Grabau, New York State Mus. Bull. 69, pp. 1056, 1061, 1067. 

Coeymans limestone, Becraft limestone, Port Ewen shaly limestone: Becraft Mountain, New York. 

1903. Spirifer cyclopterus. Hartnagel, idem, p. ll64. 

Stromatopora layer [included by Hartnagel in the basal Helderberg]: Hill east of Manlius, N. Y. 

1903. Spirifer concinnus. Van Ingen and Clark, idem, pp. ll88, ll89, ll91, 1203, 1207. 

Basal Coeymans limestone, Coeymans-New Scotland transition shaly limestone, lo.wer and upper New Scotland, 

and lower and upper Port Ewen beds: Becraft Mountain, Columbia County, N.Y. 

Oriskany: Glenerie, Ulster County, N·. Y. 

1905. Spirifer cycloptems. Williams and Kindle, U. S. Geol. Survey Bull. 244, pp. 28, 33, 48. 

"Oriskany" coarse sandstone: East.Fork of Powell River, above flouring mill, Wise County, Va. 

"Oriskany" sandy and cherty beds: Along Southern Railway northeast of Big Stone Gap, Wise County, Va. 

Giles sandstone: 1! miles south of Rocky Gap, Bland County, Va. 

1905? Spirifer eyclopterus. Clarke, 1 New York State Mus. Bull. 80, p. 149. 

Grande Greve (Oriskany) limestone: The Blowhole, Gaspe, Canada. 

1906. Spirifer cyclopterus. Shimer, idem, pp. 181, 182, 189, 207, 208, 212, 220, 224-228, 232, 233, 248-249, 265. 

Lower Coeymans, lower n,ncl upper New Scotland, 2 lower Oriskany (Trilobite beds), and UI)per Oriskany (zone 

· of S. murchisoni): Trilobite Mountains, N. Y. 

1905. Spir1'jer cyclopterus. Clarke and Luther, New York State Mus. Bull. 82, p. 40. 

Lower Helderbergian limestone: Jamesville, Onondaga County, N. Y. 

1907. Spirifer eym,indis. Clarke, New York State Mus. Bull. 107, p. 255, figs. 

:Lower Devonic: Presque Isle Stream, Chapman Plantation, Aroostook County, Maine. 

This is a. plicated Spirifer of small size, 6 to 9 low plications, square or rounded lateral 

extremities, and semicircular outline; hinge line straight, a little less than the greatest width· 

of the shelL; proportion of length to width varying from 8 or 9 to 12; greatest width just below 

the posterior margin, rarely at the.hinge. Pedicle valve strongly convex, but only slightly more 

so than the brachial valve; gibbous ov:er umbonal region:· 

1'he greatest depth of the pedicle valve is equal to about one-third the length' and is 

situated at two-fifths of the distance from beak to front. Transyerse profile low, broadly subcarinate .. Umbone tumid, obtuse, strongly arched over the hinge; beak incurved so that the 

tip is not the most posterior point of the shell. Cardinal area of medium height, curved, nearly 

in the plane of the edges of the valve.· Delthyrium acute; rarely discernible because of the 

incurved beak. The 1nusculature on the interior is in general distinctly impressed, though 

·obscure in some specimens. It extends from one-third to two-fifths the length of the valve and 

is divided into two portions by the median sinus. · The 1nusculature is longitudinally. striated; 

adductor scars not discernible. The dental lamellre are well developed, widely separated, 

slightly divergent; they extend about one:-fourth the length of the shell and are situated either 

in the second groove on each side of the median sinus or on the corresponding inner fold. 

1 Ciarko horo records Ells's citation of S. cyclopterus from this locality and states that it is "probably S. murchisoni"; Clarke found Spirifer 

murchisoni horo, but apparently ho did not find Spirifer cyclopterus. 

» Shlmor divides tho New Scotland here into lower (45 feot) and upper (125 feet), the division being based upon the rarity of Spirifer cycloptCT1J,8 

ill tho lowor and its abundance in the uppor member. 
90 FAUNA OF THE CHAPMAN SANDSTONE OF MAINE. 

The brachial valve is strongly convex, only slightly less so than the pedicle valve.· Longitudinal profile deeply .arcuate; the greatest depth is at the n1iddle and is equal to about .onethird the length of the brachial valve. 

Transverse profile carinated by the median fold. The umbonal part of the valve is deeply 

arched downward to the hinge; rarely does the posterior extremity extend beyond the hinge 

line. On internal molds of the brachial valve a pair of short, rounded incisions, about a millimeter in length, represent the crural bases adherent to the bottom of the valve. The musculature of the brachial valve is not impressed; the median septum or elevated line in the brachial 

valve extends about half the length of the shell. On the surface six to eig~t plications appear 

each side of the fold and sinus; the prevailing number of plications is seven, or seven with an 

indistinct eighth plication; in one large shell nine ribs were counted. The extreme lateral 

extremities are smooth, the outermost plications being obsolescent and the ribs increasing in 

strength and width toward the middle. The plications are strong, rounded to subangular, 

interspaces rarely equal to the width of the ribs. The sinus of the pedicle valve is deeply 

excavated and slightly flat in the bottom; it is equal in width to two or three of the bounding 

ribs and is extended tonguelike forward and toward the fold of the opposite valve. The 

median fold is strongly elevated, subcarinate, and equal in width to two or three of the bounding 

ribs. The finer surface ornamentation consists of extremely fine radiating lines visible only 

under a hand lens, and crossed and more or less interrupted by stronger or weaker concentric 

lines of growth. This ornamentation is discernible only on external molds. The shell structure 

is finely fibrous, impunctate. The inner layer of the shell is thicker than the outer layer and 

the fibers are radially or prismatically arranged as usual. In the outer _thin layer the fibers are 

concentrically arranged, curving over the ribs, and are parallel to the lines of growth. The 

largest specimen observed, a pedicle valve from the west side of Edmunds Hill (Pl. II, fig. 8) 

is 23 by 34 millimeters and has seven or eight ribs on each side. The smallest specimen observed 

(Pl. I, fig. 8), from the same locality, is 7 millimeters long and 10 millimeters wide and has six 

ribs on each side. Large specimens 20 millimeters long or more are not rare; but the n1ajority 

. of specimens are from 14 to 18 millimeters long. 

Locality: Chapman sandstone, Edmunds Hill, Presque Isle Stream, and 2~ miles west of 

Presque Isle Stream, Chapman Township, Aroostook County, Maine. 

U. S. National Museum, catalogue Nos. 59738 to 59740. 

Comparison of Chapman forms of Spirifer cyclopterus with New Yorlc material.-This species 

was originally described as having from five to seven rounded plications on each side of the 

fold and sinus. Only two among scores of individuals from Edmunds Hill were observed with 

five plications; seven seems to be the predoi:ninant number, as in the New York types. Individuals with eight plications are also rather common in the Chapman sandstone, and one 

specimen was found having nine ribs on the side. Hall fails to mention the occurrence of eight 

plications in theN ew York Helderbergian forms of the species, but that number may be counted 

on the figures of his types as illustrated· in Plate XXV, figures 1 h, 1, m, n, and ( ~) r. 

In the Coeymans limestone of New York and New Jersey, or basal Helderberg-an early 

stage of the range of the species-young specimens of Spirifer cyclopterus have only three, four, 

or five plications and are with difficulty distinguishable from the antecedent Spirifer vanuxemi 

of the Manlius. ·The occurrence of seven plications in the young individuals from the Chapman 

sandstone of Edmunds Hill suggests that the Chapman represents a stage after the species had 

become substantially fixed. This deduction is supported by the large size at maturity, and 

also by the strengthened musculature-a feature that will be referred to again. 

The few specimens from the locality 2! miles west of Presque Isle Stream have only five 

·rib~ on each side of the fold and sinus,. and one individual has pnly four. The shells are also 

of smaller size. If really identifiable with Spirifer cyclopterus, they suggest either an earlier 

stage or adverse conditions of environment. 

The larger Chapman specimens represent to some extent a transition toward the Oriskanian 

Spirifer murchisoni Castelnau. The typical Spirifer cyclopterus is distinguished by its rounded, 

not acute lateral extr~mities, the relative faintness of the muscular scars in the pedicle valve, 
. MOLL USCOIDEA. 91 

n,.ncl the smaller size. In size and in abundance of individuals with strongly impressed musculature the Chapma'n shells appro·ach the larger and later species Spirifer murchisoni; but they 

have the rounded shoulders and less transverse outline of the normal Spirijer cyclopterus, which 

is n1ore prin1itive both ehronologically n,nd phylogeneticaliy than Castelnau's Oriskanian species. 

Stratigraphic and geologic significance of the evolution of Spirifer cyclopterus.-In the succession fr01n the typical Silurian, through the }Ielderberg, into the basal Devonian of western 

Europe, represented by the Oriskany of North An1erica and the Taunus quartzite or Siegen graywacke horizon of Europe, the evolution of the Spirifers, frmn the plicatus-inchoans-"mercurii" 

type through the cyclopterus-hysteiicus and into the 1nurchisoni~primmvus type, furnishes an 

achnirable exmnple of the intimate relation between phylogenetic evolution and geologic 

chronology. · 

The murchisoni-p1vimmvus forn1 of Spirifer, evidently derived fron1 the cyclopterus-hysteri<:,us 

type, abruptly supplants the latter as the diagnostic feature of the fauna in the Oriskany of 

An1erica and in the Tnunusian of Germany, Belgium, France, and England. These formations 

n,ppai·ently represent n very small stratigraphic range and constitute the base of- the Devonian 

of western Europe. This fauna is marked, both in America and in ·Europe, by the attainment 

of the plicn,ted fold and sinus as a fLxed specific character in Spirifer-Spi?vifer arenosus in the 

Americn,n Oriskany and Spirifer bischofi and S. daleidensis in the European .Taunusian. The 

evolution of the Oriskanian arenosus type of Spirifer from the antecedent Spirifer concinnus for1n marks the change into the basal Devonian of western Europe perhaps even n1ore 

conspicuously thn,n the eYolution of the murchisoni-primmvus Spirifers fro1n the antecedent 

cyclopterus-hyste1vicus type. · 

It is quite true that in the late I-Ielderbergian there occur, along with Spirife·r cyclopterus, 

individuals which attain 1nost of the characters of the Oriskanian Spirifer murchisoni. Such 

n. condition gives rise to the occasional recording of Spirifer murchisoni in beds older than the 

Devonin,n of western Europe. However, such citations evidently indicate only extremes of 

Spirifer cyclopterus developed during the IIelderbergian type of that species; the essential fact 

still remains that as fixed specific types the Spirifer murchisoni expression does not supplant 

the Spirifer cyclopterus type until the Oriskany 9r Taunusian epoch, ·which marks the beginning 

of the typical Devonian of DeYonshire, Cornwall, and Rhenish Europe. 

Below the Coeyn1ans lin1estone horizon, or base of the I-Ielderbergian, ~he 8pirifer cyclopte1'US expression is unknown in the New York or Appalachian succession, though in the Sil~rian 

basins of the Fundy region in North America 1 and of Poland in Europe 2 species approaching 

the Spirifer cycloptervu,s phase of developn1ent originated as early as the Aymestry or Middle 

Ludlow horizon. These Silurian species, however, seem to be indigenous to their more or less 

isolated basins. There is little or no indication that they deYeloped continuously into and 

gaYe rise to the I-Ielderbergian Spirifer cyclopterus of America, or to the Spirifer hystericus of 

the Gedinnian and 1nore especially of the basal Devonian of western Europe. In the Appalachian region of North A1nerica Spirifer cyclopterus, or species of this type, are so completely 

unknown in the Manlius or older rocks that it may be safely assumed that they did not exist. 

In fact, Spirifer cyclopterus does not attain its mature development and dominance earlier than 

the New Scotland and later horizons of the Helderberg group. 

Although in the mature stage Spirifer .cyclopterus is quite distinct from the Manlius species, 

Spirifer vanuxemi Fiall, the fact has been long recognized that in son1e of its phases the I-Ielderberg species is closely related to the antecedent Manlius limestone form. In the description of 

I Spirifer subsulcatits Hall, from Arisaig, Nova Scotia (Hall, James, Canadian Naturalist and Geologist, vol. 5, 1860, p. 145; also in Dawson's 

Acadian geology, 3d ed., 1878, p. 59.7). See also 'L'wenhofel, W. H., and Schuchert, Charles, 'l'he Silurian section at Arisaig: Am. Jour. Sci., 4th ser., 

vol. 28, 1909, p. Hil, etc. In the Arisaig section the species occurs in the Moydart and Stonehouse formations. 2 S7Jirijer bragensis Waujukow (Fauna der silurischen Ablagerungen des Gouvernements Podolien: Materialen zur Geologie Russlands, vol. 19, 

p. 138, pl. 2, figs. 7, 8, 1899), which very closely resembles Hall's Spirifer subsulcatus, occurs at Brage, Grentschuka, Orsinena, Sokola, KamentzaPodolska, and Satanova in Poland. It is the characteristic Spirifer of the Kamenetz or Coral limestone of the Polish Silurian. This horizon is 

distinguished by Pentamerus. vogulic~s De Vernouil [ Conchidium knighti (Sowerby)], Wilsonia wilsoni (Sowerby), large Chonetes, Ilionia pris~a 

Hlsingcr, Oriostoma [Poloumita], and other large gastropods and other shells besides the corals. 'l'he horizon evidently corresponds with the 

Aymestry of Britain and with the Moydart formation about Arisaig, Nova Scotia. In the Poland basin s·pirifer bragensis is reported to continue 

upward into some limestones which contain a fauna strongly suggestive of the Coeymans or lower Helderbergian. 
.... •, 

92 FAUNA OF THE CHAPMAN SANDSTONE OF MAINE • 

. Spirifer vanuxemi, Hall 1 states that the species "differs from the S. c<yclopterus of the shaly 

limestone in its smaller size and less numerous plications; as well as in the fine concentric and 

radiating strirn of the ·surface"; the supposed distinction in the finer ornament does not exist. 

I seem to have been the first to suggest2 the actual derivation of Spirifer cyclopterus from Spirifer vanuxemi Hall. In 1893 the close relationship of Spirifer cyclopterus and Spirifer vanuxemi 

Hall was indicated by Hall and Clarke, who joined $pirifer cyclopterus Hall (Helderbergian), 

S. tribulus Hall, S. murchisoni Castelnau, and Spirifer hemicyclus Meek and Worthen (all three 

Oriskanian)' in the satne group with Spirifer crispus (Linnrnus), Spirifer vanuxemi Hall, Spirifer 

saffordi Hall, and Spirifer-octocostatus Hall. This association was based chiefly on the occurrence of the same type of peculiar surface ornamentation and other characters, in spite of the 

fact that the first group of species named are true Spirifers, whereas the second group of species, 

with the exception of Spirifer vanuxemi Hall, belong to the round-shouldered, septate division 

of Spirifer known as Reticularia. 3 The determination of the same type of surface ornamentation in both Spirifer cyclopterus and S. vanuxemi Hall leaves the only distinction between these 

two. species the larger size and more numerous ribs of S. cyclopterus. 

Shimer has describe<:}. from the Coeymans limestone of Trilobite Mountain, N.Y., young 

Spirifer cyclopterus having only three or four ribs and with rounded outline and convexity as 

in Spirifer vanuxemi Hall; but the young Spirifer cyclopterus specimens indicated are proportionately wider than Spirifer vanuxemi. He observes that "with the exception of this last 

fact, the similarity between the two species is almost perfect and suggests a possible derivation." 4 

A couple of years earlier Weller 5 observed: "A few small specimens [from the Coeymans limestone of New Jersey], which are apparently. the young of this species [8. cyclopterus], agree 

closely with ·specimens of vanuxemi from the Manlius limestone, and .at first were so identified, • 

and some of these retain the fine surface markings of the species. It is possible that S. vanuxemi 

is ancestral to this Helderbergian species." 

It Js thus seen that Spirifer cyclopterus and Spirifer vanuxemi both have the same peculiar 

fine surface markings; both are small, with both valves subequally convex and with only a 

. few rounded plications, nonextended outline, and rounded cardinal extremities. Finally, 

and of still greater importance, where Spirifer cyclopterus first appears in the Coeymans limestone 

the young are with great difficulty, if at all, distinguishable from Spirifer vanuxemi.. Spirijer 

cyclopterus begins its appearance in the Coeymans where S. vanuxemi ends its existence; and 

Spirifer cyclopterus differs from S. vanuxemi only in its slightly wider form, less broadly rounded 

shoulders, somewhat ·larger size, and slightly greater number of plications at maturity-all 

features that might be expected to develop along this line of descent. 6 It is thus apparent, 

as has been indicated by many paleontologists, that Spirifer vanuxemi is the ancestral form of 

Spirifer cyclopterus; and this conclusion receives additional support from the fact that Scupin, 

1 Paleontology of New York, vol. 3, p. 198, 1859. 

2 Williams, H. S., The life history of Spiriferl;:evis: Am. Jour. Sci.,3dser., vol. 20,p. 459, 1880; also in New York Acad. Sci. Annals, vol.ll, 1881. 

a Certain forms of Spirifer crispus and of the variety simplex Hall, as occurring in the Niagaran of the Mississippi Valley, possess a median septum, dentallamellre, and minute radiating spines arranged in fringes, characters which serve to remove the shells from true Spirifer and to associate them with R~ticularia. (See Kindle, E. M., and Breger, C. L., Paleontology of the Niagara of northern Indiana: Indiana Dept. Geology 

and Nat. Resources Twenty-eighth Ann. Rept., p. 442, pl. 8, figs. 26-28, 1904.) The same conditions have apparently been noted in European 

specimens of Spirifer crispus by Scupin. On the other hand, forms identifiable with Spirifer crispus from the Niagaran or ·wenlock faunas of Maine, 

New York, and Great Britain distinctly lack the median septum and fine radial ornament, as well as.any conspicuous dental plates, and app"ear 

to be true Spirifer forms. Spirifer octocostatus Hall and Spirifer saffordi both possess a median septum, dentallamellre, and fringes of radial spines 

and belong in the same section of ,Reticularia with the septate forms of Spirifer (Reticularia) crispa. The genus Cyrtinopsis has been erected by 

Scupin ( Neues Jahrb., 1896, vol. 2, p. 247; Spiriferen Deutschlands, 1900, p. 212) for Kayser's Devonian Spirifer undosus and was apparently intended 

to include the septate Spirifer (Reticularia) crispa. It may ultimately prove advisable to retain the generic name Cyrtinopsis for Reticularias with 

only single-barreled spines, to restrict the name Reticularia to species having double-barreled s'pines, and to adopt Gemmellaro's Squamularia (see 

Girty, G. H., Carboniferous formations and faunas of Colorado: U. S. Geoi. Survey Prof. Paper 16, p. 387, 190~) for Reticularia-like shells lacking 

the median septum and dentallamellre in the pedicle valve. The generic name Cyrtinopsis, in the strictest sense, was used by Scupin for Reticularia-like fossils in which the median septum, instead of being intercalated between the dentallamellm, as in true Reticularia, originated by the 

union of the forward ends of the converging dentallamellre, as in Cyrtina and some SpiriferiDa species. · 

4 New York State Mus. Bull. 80, p. 248, 1905. 

5 Paleontology of New Jersey, vol. 3, p. 287, 1903. 

o See Raymond, P. E., Developmental changes in some common Devonian Brachiopoda; Am. Jour •. Sci., 4th ser., vol. 17, pp. 2i9-300, pls. 

12-18, 1904. According to Raymond, the steps in the evolution of Spirifers are, first, the development of the transversely extended shell from 

narrow, nonextended forms; the development of the earlier round-shouldered types into square-shouldered forms, then into the type having 

acute extremities, and finally into the broad pennate and mucronate forms; the increase in the number of plications and in the size; and the 

increasing dissimilarity in c:mvexity of the two valves. · 
MOLL USCOIDEA. 93 

working in Europe on entirely independent lines and with different species, has concluded 

that the ancestral Spirifers are smooth forms of the Reticularia (Cyrtinopsis) type which evolve, 

t]u·ough some such form as SJJirifer mercurii Gosselet in the Gedinnian-a species resembling 

S. vanuxemi or intermediate between S. vanuxemi and early S. cyclopterus, but septate-into 

th.e group of S. hystericus (equivalent to mature S. cyclopterus, tribulus, etc.), indicating a 

line of descent si1nilar to that occurring in America. · 

To geologists acquainted with Spirifer cyclopterus and S. murchisoni th~ derivation of the 

latter from the former is more or less apparent. Spirifer murchisoni differs from S. cyclopterus 

in its slightly larger size, less rounded and sharper cardinal extremities, more transverse outline, and persistently very strong· musculature, a series of features less distinct and less constant than the differences between S. cyclopterus and S. vanuxemi. The S. murchisoni form 

fu'St appears in the uppermost Helderberg associated with 8_. cyclopterus in such a way that 

the dmivation of the S. murchisoni expression from S. cyclopterus is always self-evident. In 

the Oriskanian S. cyclopterus is supplanted by S. murchisoni. It is to be noted that S. cyclopte·rus, wherever recorded from the Oriskanian-as at Glenerie, N. Y., and at the Blowhole 

localities, Gaspe-is accompanied by S. murchisoni. Such specimens of S. cyclopterus might 

be regarded as unmature S. murchisoni and as corroborating the derivation of the latter from 

the former. In this connection, too, it should be borne in mind that every large collection 

of S. cyclopterus contains some individuals varying toward the 'vide form, or the sharper 

cardinal extremities, or larger size, or stronger musculature of S. murchisoni; and that the 

features named, by which S. murchisoni differs from S. cyclopterus, are among the evolved 

features to be expected in this line of descent from S. cyclopterus to S. murchisoni. 

A feature which has received scant attention in the study of the evolution of Spirifers 

is the strengthening of the muscula.r impressions in the pedicle valve. This strengthening is 

due to the fact that the cavities on the interior of the valve between the dentallamellre and 

latero~umbonal portion of the shell are filled in, or calloused, toward maturity, so· that in internal 

molds the clean-cut incisions of the lamellre are absent and the musculature assumes a ponderous appearance well typified by Hall's Spirifer arrectus ( =S. murchisoni Castelnau and the 

corresponding European S. prim::.evus Steininger). As the developing of the shell callosity is . 

a feature of maturity or senility, and the arrectus type of muscJ.Ilature· may develop in the 

senile stage in Spirifers where it is 1iot in earlier stages normal, this characteristically deeply 

impressed musculature 1nay be regarded in the light of a feature of maturity or senility in 

evolution.. The early forrns of Spirifer cyclopterus have a nohimpressed musculature and distinct dentallamellre; the later S. murchisoni has normally the characteristic deeply impressed 

n1usculature, shell callosities, and absence of the incisions left on internal molds. by the dental 

latnellre. Between .these forn1s so distinct are intermediate types in which specimens of 

undoubted S. cyclopterus affiliation have the shell callosities and thick impressed musculature . 

either only at maturity or else beginning rather early in the life of the individual. The fact 

that a large number of the Chapman specimens of Spirifer cyclopterus ha:ve a very strongly 

impressed musculature shows thmn to be near the mature or senile stage of the species, and 

the fact that these speci1nens are much later than the first appearance of S. cyclopterus (Coeymans limestone) is shown also by young specimens having seven lateral plications. Forms with 

only five ribs in the young or at maturity are extremely rare. Among the Chapman specimens are many individuals tending toward Spirifer murchisoni in the transversely extended 

outline. One or two specimens have square or acute hinge extremities as in S. murchisoni. 

The not uncommon deepening of the musculature impression also recalls S. murchisoni, but 

in the latter the musculature is relatively broader. 1 ·The strong ribs, sometimes subangular, 

especially on the internal mold, are also an approach towardS. murchisoni. On the whole it 

may be concluded that the Chapman specimens of Spirifer cyclopterus indicate astage of evolution much nearer the Oriskany S. 1nurchisoni than the Manlius or Coeyn1ans S. vanuxemi. 

1 'L'hls was indicated by Shimer (op. cit., p. 248), who states also that the internal mold of the plications is less pronounced in S. cyclopterua 

than in S. murchisoni, a condition tbat is reversed in the ,Chapman specimens. 
94 FAUNA OF THE CHAPMAN SANDSTONE OF MAINE. 

From what has been indicated of the variation of the Chapman specimens of Spirijer 

cyclopterus toward S. murchisoni, it might be presumed that there is some doubt attending 

their identification with S. cyclopterus, but this is by no means true. The great bulk of the 

specimens· are most typical of S. cyclopterus, and those, relatively very few, individuals which 

in one or two features vary towardS. murchisoni agree with S. cyclopterus in their main features, 

besides being associated with normal forms. 

European equivalent of Spirifer cyclopterus.-It will at once be recognized that Spirifer 

cyclopterus is hardly distinguishable from many forms of S. hystericus Schlotheim, the fossil 

.which, with S. primcevus, is the characteristic species of the Taunusian or Siegen graywacke. 

However, so variable is the specific assemblage designated S. hystericus by authors that it is 

very difficult to define satisfactorily the limits of the species or even to recognize which of 

the variable forms was intended by. Schlotheim as the type. According to Scupin/ "As a . 

. rule the greatest width, which is along the hinge line or rarely somewhat below it, is only about 

double the length of the shell; however, by the perinate elongation of the lateral portions, 

the width may be as much as six or more times the length." Spir?fer cyclopterus in complete 

uncrushed specimens is practically never twice as broad as long, the width, in fact, rarely 

exceeding 11 times the length. The maximum width is normally below the hinge line and the 

cardinal extremities are rounded; only very rarely do "sports" occur with the maximum 

width at the hinge line. Such "sports" seem to be the normal form in S. hystericus. The 

number of ribs in S. hystericus, accordmg to Scupin,Z "varies mostly between nine and thirteen 

on each side, though also passing below these figures." Spirifer cyclopterus does not have 

more than nine plications, and extremely rarely as many as nine; less rarely eight. The species 

was, in fact, described by Hall as having only five to seven ribs on each side. In spite of 

these differences and a few minor points that would seem to indicate an easy distinction between 

S. cyclopterus Hall and S. hystericus Schlotheim, there are many European Spirifers, called 

S. hystericus, which seem to be indistinguishable specifically from S. cyclopterus. Among 

these are S. hystericus Scupin/ a small form with only six or seven ribs on each side, the ribs 

subangular and about as wide as the interspaces, the greatest width a third the length in front 

of the hinge and equal to about one and two-thirds times the height. This form is almost a 

typical S. cyclopterusJ· it is slightly more transverse, though no more so than many of those 

specimens of 8 .. cyclopterus which grade toward S. murchisoni in this respect. In fact, if 

Scupin's figure is, as there is every reason to believe, a good representation of the original 

specimen, such specimens would with little if any hesitation be referred to S. cyclopterus were 

they found in Helderbergian faunas in America. The specimens do not, however, answer to 

the description. of normal B. hystericus. Compare also Spirifer hystericus, from the Siegen 

graywacke of Seifen, in the W esterwald, figured by Drevermann. 4 

Of the modifications of the Taunusian S. hystericus, one, Spirifer prohystericus Maurer, 5 can 

not be distinguished from some of the specimens of S. cyclopterus as represented in the Chapman fauna. The German fossil is a large form of S. cyclopterus, having. the musculature well 

developed, but with distinct incisions of the dentallamellre. It has six, seven, or eight subangular ribs, the sinus angular and fold carinate, and the width normally less than 1! times the 

height in the Freusburg specimens, though it is more elongated transversely in the typical 

Seifen form. The type is homologous with the form of S. cyclopterus prevalent in the Oriskany 

of Glenerie, Ulster County, N. Y~ 

1 Scupin, Hans, Die Spiriferen Deutschlands, p. 13, 1900. That Spirifer hystericus is normally a transversely elongated species with acute 

cardinal extremities and with the width about twice the height or more is not only indicated by Scupin's explicit description and some of his 

figures, but may also be seen by a glance at Drevermann's figures I, 2, 5, 7 (Palaeontographica, vol. 50, pl. 30, p. 263, 1904) of S. hystericus from the 

Siegen graywacke about Seifen, in the Westerwald. 

2 Idem, p. 13. 

a Idem, pl. 1, fig. 3. 

4 Palaeontographica, vol. 50, p. 253, figs. 3, 4, 6 (not figs. 1, 2, 5, 7), 1904. 

5 Die Fauna des rechtsrheinischen Unterdevons, p. 19, Darmstadt, 1886. Scupin (op. cit., p. 15, pl. 1, figs. 9 and 10 a-d) takes the liberty to 

change the name to S. subhystericus. The species is from the Taunusian or Spirijer primrevus zone of Seifen, near Dierdorf, and also at Freusburg. 
, 

MOLLUSCOIDEA. 95 

The "Spi'ri.fer me?'C'IJ,?'ii" Gosselet, from the Gedinnian, bears a strong resemblance superficin1ly to s1nall etuly forms of S: cyclopterus approaching S. vanuxemi, but the Belgian species has a 

median septum in the pedicle valve 1 and is therefore not a Spirifer, but belongs rather in the 

Reticularia-Cyrtinopsis-Delthyris group. 

SPIRIFER MURCHISON! Castelnau.2 

Plate I, figures. 3, 10, 23, 25, 26; Plate II, figure 9. 

cf. 1842. Spirifer quichua. D'Orbigny, 3 Voyage dans !'Amerique meridionale, Paleontologie, p. 37, pl. 2, fig. 21. 

''Silurian" [Lower Devonian]: Chuquisaca, Bolivia. 

not 1.843. Spirifer (OIJrtia) murchisoniamts. De Koninck, D'Omalius d' Halloy, Precis elementaire de geologie, p. 523. 

1.843. Spinfer murchisoni. Castelnau, Essai sur le systeme silurien del' Amerique septentrionale, p. 41, pl. 12, figs. 1-2. 

Schoharie, N: Y. · · 

1846. S])infer hmukinsii. Morris and Sharpe, Geol. Soc. London Quart. Jour., vol. 2, p. 276, pl. 11, fig. l. 

Devonian: Falkland Islands. 

1859. S]Yirifer arrectus. Hall, Paleontology of New York, vol. 3, p. 422, pl. 97. 

Oriskany sandstone: Throughout New York State and at Cumberland, Md. 

1862. Spirifera a.rrecta. Hitchkock, Portland Soc. Nat. Hist. Proc., vol. 1, pt. 1, p. 79. 

Oriskany sandstone: Parlin Pond to Aroostook River, Maine. 

1863. Spirifera arrecta. Billings, Geology of Canada, p. 960, fig. 466. 

Oriskany sandstones: North Cayuga, Canada (p. 361). 

1808. S])irifera engelmanni (not Meek, 1860). Meek and Worthen, Illinois Geol. Survey, vol. 3, pl. 8, figs. 7a, 7d (not 

fig. G). 

Oriskany siliceous limestone: Union County,. Ill. 

1874. Sp·ir·ifera cycloptm:a. Billings, Paleozoic fossils, vol. 2, pt. 1, p. 48, pl. 3a, figs. 4, 4a (not ? figs. 4b, 4c). 

Gaspe limestone No. S: Grande Greve and Indian Cove, Gaspe, and Split Rock, Perce, Quebec. 

1870. Sp·irifer arrect·us. Barrett, Lyceum Nat. Hist. New York City Annals, vol. 11, p. 297. 

Oriskany: Bennett's quarry, Port Jervis, N.Y. · 

1877. Spirijer arrect·us. Barrett, Am. Jour. Sci., 3d ser., vol. 13, p. 387. 

"T1·ilobite beds" 4 belonging to the Upper Pentamerus division: Bennett's quarry, near Port Jervis, N. Y. 

1879. S])infera derbyii. Hathbun, Boston Soc. Nat. Hist. Proc., vol. 20, p. 26. 

Devonian: Hio Maecuru and Rio Cun1a, Para, Brazil. 

1882. Spir·ijer arrect'l.tS. I. C. White, Pennsylvania Second Geol. Survey Rept. G6, p. 123. 

Or.iskaJlY limy shales: South of Carpenters Point, Pike County, Pa. 

1882. Sp•ir1jera a.rrecta. Stevenson, Pennsylvania Second Geol. Survey Rept. TT, pp. 86, 103, 132, 148. 

Oriskany, Hyndman section: Exline road, King Township, and Bedford Springs, Bedford County, Pa. 

?1883. Sp·irifera cycloptera (not ?Hall). Ells, Canada Geol.-Survey Rept. Progress for 1880-1882, pp. 9DD, 14DD. 

Upper Gaspe limestone (Oriskany): Perce Rock, the Blowhole, Indian Cove, Grande Greve, and Little Gaspe, 

Gaspe Bay, Quebec. 

1883. Spinfera arrecta. Hall, New York State Geologist Second Ann. Rept., pl. 58, figs. 24-27. 

Or.iska,ny sandstone: Albany County, N. Y. 

1883. Spinfera arrecta. I. C. White, Pennsylvania Second Geol. Survey Rept. G7, pp. 297, 305, 346. 

Oriskany (cherty beds): Grove Bros.' tunnel, Cooper Township; and along the road in eastern part of Mahoning 

'l'ownship, Montour. County, Pa.; Upper Augusta Township, Northumberland C~mnty, Pa. 

1884. Spinfera raricosta (not Conrad). Walcott, U. S. Geol. Survey Mon. 8, p. 135, pl. 4, fig. 2 (not fig. 2a; not pl. 

14, fig. 12). Lower Devonian limestone: Lone Mountain, 18 miles northwest of Eme~a, Eureka district, Nev. 

1884. S1)irijer arrectus. · Ewing, Pennsylvania Second Geol. Survey Hept. T4, p. 431. 

Oriskariy coarse-grained sands with calcareous cement: Alexander quarry, between Julian and Unionville, 

Center County, Pa. 

1885. Spirifera arrecta. I. C. White, Pennsylvania Second Geol. Survey Rept. T3, pp. 119, 274. 

Oriskany coarse sandstone: Saud Ridge, Mapleton, Huntingdon County, Pa .. 

?1885. S])irifera cycloptera (?not Hall). Ells, Canada Geol. Survey Rept. Progress for 1882-1884, p. 24E. 

Gaspe limestone No.8: Grande Greve, Gaspe Bay. 

1887. S])irifera arrecta. Ami, Canada Geol. Smvey Ann. Rept., new ser., vol. 2, p. 9N. 

Oriskany slates and sandstones: Campbell River, at mouth of the Don, New: Brunswick. 

1889. Spirifera arrecta. Claypole, Pennsylvania Second Geol. Survey Rept. 03, p. 151. 

Oriskany sandstone: Grove Bros.' lime quai'l'y, Montour County, 3~ miles from Rupert, Columbia County, Pa. 

1889. Spirifera arrecto.. Schuchert, New York State Geologist Eighth Ann. Rept., p. 53. 

' Soc Oossolot, J. A. A., Esquisso geologique du Nord de la France, pl. 1, fig. 8, 1880. 

2 Docs not occur in the Chapman fauna. Sec remarks on p. 86, which likewise apply to this species. 

a 'J'his species is a pauciplicate form closely resembling Spirifer murchisoni and may prove to be identical with the paueiplieate form of that 

species. 

• 'l'hcsc arc now culled the Dalmanitcs dcntatus zone. They represent a horizon between the Port Ewen limestone (No. 6 of Barrett's section) 

nnd tbo Orisknny, und arc commonly included with the Oriskany. · 
96 FAUNA OF THE CHAPMAN SANDSTONE OF MAINE. 

1889. Spirije:ra arrecta. Simpson, Pennsylvania Second Geol. Survey Rept. 03, p. 208. 

Oriskany: Cumberland, Md.; New York; and at Cayuga, Canada West. 

Oriskany sandstone: Sandy Ridge sand quarry, south of Blacklog Creek. 

Oriskany lime-sand beds: South end of Royers Ridge, and on Royers Ridge, north of the road crossing. 

Bot}:l. localities at Orbisonia, Huntingdon County, Pa. 

1892. Spirije:r arrectus. Clarke, Am. Jour. Sci., 3d ser., vol. 44, p. 413. 

Oriskany hard cherty limestone: Becraft Mountain, Columbia County, N.Y. 

cf. 1892. Spirifer t~p. a. Ulrich, N eues Jahrb., Beilage Band, vol. 8, p. 67, pl. 4, fig. 22. 

Lower Devonian (with Leptoccelia jlabellites): Totora, Bolivia. · · 

cf. 1893. Spirijer vogeli. Von Ammon, Gesell. Erdkunde Berlin Zeitschr., vol. 28, p. 362, fig. 6. 

Devonian: Taquarassu, Matto Grosso, Brazil. 

1893. Spirije:r arrectus. Hall and Clarke, Paleontology of New York, vol. 8, pt. 2, pp. 17, 19, 37, pl. 33, figs. 24-27. 

Oriskany sandstone: Albany County, N.Y. 

1894. Spirije:r arrectus. Darton, Geol. Soc. America Bull., vol. 5, p. 375. 

Oriskany quartzite ["Newfoundland grit" or Kanouse standstone]: Kanouse, 750 yards northeast of the depot 

at Newfoundland, N.J. 

?1895. Spirije:ra arrecta. Ami, Canada Geol. Survey Ann. Rept., new ser., vol. 6, p. 15Q. 

Nictau beds: Nictau, Nova Scotia. 

1897. Spirije:r murchisoni. Schuchert, U. S. Geol. Survey Bull. 87, p. 398. 

Oriskany: Schoharie and Albany counties, N.Y.; Cumberland, Md.; Cayuga, Ontario; nea~ Totora, Bolivia. 

1897. Spirije:r worthenanus (pars). Schuchert, idem, p. 409. 

Oriskany: Union County, Ill. 

cf. 1897. Spirije:r antarcticus (not of Morris and Sharpe). Kayser, Deutsch. geol. Gesell. Zeitschr., vol. 49, p. 297, pl. 9, 

figs. 1, 2, 4 (fig. 3 approaches normalS. murchisoni). 

Lower Devonian: Jachal Valley, Argentina. 

1898. Spirije:r arrectus s. str. (pars). Scupin, idem, vol. 48, p. 463, pl. 17, figs. la, lb. 

Lower Devonian: Chuquisaca, Bolivia (figured specimens); New York. (Not South Africa.) 

1898. Spir7fe:r arrectus var. antarcticus (pars). Scupin, idem, p. 464, pl. 17, figs. 2a, 2b, not figs. 3a, 3b [Spirijer chuquisaca 

Ulrich, 1892, or the apparently identical Spirijer boliviensis D'Orbigny, 1842], and not figs. 4a, 4b [Spirije:r 

capensis Von Buch ?]. 

Oriskany: New York. 

cf. 1898. Spirijer arrectus var. hawkinsii (not Morris and Sharpe). Scupin, idem, p. 465, pl. 17, figs. 5a, 5b. 

Lower Devonian: lela (figured specimen) and Totora, Bolivia (Ulrich); Jachal Valley, Argentina (Kayser). 

Not Falkland Islands shells. 

1899. Spirijer arrectus. Prosser, New York State Geologist Seventeenth Ann. Rept. (for 1897), p. 341. 

Oriskany sandstone: Countryman Hill, Helderberg Mountains, N.Y. 

1900. Spirijer arrectus and S. "cyclopte:rus Billings." Williams, U. S. Geol. Survey Bull. 165, pp. 89, 92. 

Moose River sandstone: Parlin Pond and Brassua Stream, Somerset County, Maine. 

1900. Spirije:r murchisoni. Schuchert, Geol. Soc. America Bull., vol. 11, pp. 294, 311-312, 315. 

Oriskany and (?)Helderbergian: Potts Grove, Northumberland County, Pa.; Newry, Blair County, Pa.; Keyser, 

Mineral County, Vl. Va.; also in Pendleton County, W.Va., on the north fork of the South Branch of Potomac 

River. 

1900. Spirije:r murchisoni. Clarke, New York State Mus. Mem., vol. 3, No. 3, pp. 46, 74, 76, 77, pl. 6, figs. 26-30. 

Oriskany siliceous limestone: Becraft Mountain, Columbia County·; near Kingston, on the West Shore Railroad, 

half a mile southeast of Rondout Creek, in Ulster County, N.Y., Cuddebackville to Port Jervis, Orange County,. 

and on West Mountain, Schoharie, N. Y. 

1901. Spirijer arrectus. Prosser, New York State Geologist Eighteenth Ann. Rept., p. 59. -

Oriskany dark-gray calcareous sandstone: Altamont section, Helderberg Mountains, N. Y. 

?1901. Spirijer murchisoni. Schuchert, Am. Geologist, vol. 27, p. 249. 

Upper Oriskanian: 1 St. Helens Island, Montreal, Canada. 

1903. Spirije:r murchisoni. Weller; Paleontology of New Jersey, vol. 3, pp. 94, 95, 97, 102, 329, 354. 

Dalmanites dentatus zone, or lower Oriskany (siliceous limestone): Trilobite Ridge, Peters Valley, N.J. 

Orbiculoidea jervensis zone, or middle Oriskany (siliceous limestone): ,.Verden farm, Nearpass district; also at 

the first crossroad over Wallpack Ridge, 3 miles south of New York State line; and at the second road, 5 mile~. 

south of the State linej New Jersey. 

Spirijer murchisoni or upper zone of Oriskany (siliceous limestone beds): Werden farm, Nearpass district; 1! 

miles north of Layton; three-fourths of a mile west of Layton, on the road to Dingmans; also at Peters Valley, 

about half a mile east of Flatbrookvil!e, and in the sandstones forming the top of the Oriskany, three-fourths 

of a mile north of Peters Valley, N. J. 

1 In 1910, upon critical study of the breccias of St. Helens Island, I failed to discover any true representatives of the species Spirifer murchisoni, 

Specimens of Spirifers presenting the characters of both S. gaspensis and S. cumberlandica were found in the limestone fragments with S. arenosus. 

These have the deeply impressed musculature of the pedicle valve, giving, in molds, the characteristic tonguelike projection seen inS. murchisoni, 

but no specimens presenting the typical characters of that species were seen. See Williams, H. S., Fossil faunas of the St. Helens breccias: Roy. 

Soc. Canada Trans., 3d ser., vol. 3, p, 224, 1910. 

'!: ' 
MOLL USCOIDEA. 97 

?1903. Spirifer macrothyris (pars). ·weller, idem, pp. 105, 375, pl. 52, fig. 3 (not figs. 1, 2). 

Newfoundland grit: Newfoundland, N. J. 

1903. Spirifer murchisoni. Van Ingen and Clark, New York State Mus. Bull. 69, pp. 1202, 1203, 1207. 

Oriskany arenaceous limestones: Glenerie and Rondout, N.Y. . · 

1903. Spirifer derbyi. Katzer, Geologie des unteren Amazonasgebietes, p. 274, pl. 11, fig. 3. 

Spirifer sandstone: Rio Maecuru and Rio Curua, Para, Brazil. 

1905. Spi1'ijer arrectus. Harris, Guide to the geology of Union Springs, p. 4, pl. 13, fig. 3. 

Oriskany sandstone: Yawger's Woods, Union Springs, N.Y. 

cf. 1005. Spirifer antarcticus (not Morris and Sharpe). Thomas, Deutsch. geol. Gesell. z·eitschr., vol. 57, p. 267, pl. 

13, figs. 22 (?), 23-25. 

Devonian: Cerro del Agua Negra, on the road to Gualilan, Argentina. 

1905. Spirifer nturchisoni. Clarke, New York State Mus. Bull. 80, pp. '140, 143, 145, 148, 149, 151, 169. 

Perce limestone: Blowhole and Perce Rock, Quebec. 

Grande Greve limestones, or divisions 7 and 8 of the Gaspe series, Mount St. Anne, Barre Brook, and other localities on the north shore of Gaspe Bay, Quebec. . 

1905. Spirijer murchisoni. Shimer, idem, pp. 205, 206, 227-229, 234, ?51, 265. 

Port Ewen blue limestone; Port Ewen-Oriskany transition siliceous limestone in coarse shaly beds; Lower 

Oriskany, with Dalmanites dentatus (dense blue limestone); Oriskany zone with Orbiculoideajervensis (darkblue heavy-bedded siliceous limestone); upper Oriskany or Spirijer murchisoni zone (dark-blue dense limesto'ne): Trilobite Mountain, N.Y. 

1905. Spirijer murchisoni. Williams and Kindle, U. S. Geol. Survey Bull. 244, pp. 34, 39,· 43, 48. 

Lewistown limestone [in beds of late Helderbergian age]: Cliff on river bank, half a mile below iro'n furnace, 

Covington, Alleghany County, Va. 

Oriskany coarse sandstone: Rear of Alabama Row, Wliite Sulphur Springs, W.Va.; half a mile southeast of the 

iron furnace, Jackson River,· Covington, Alleghany County, Va.; half a mile west of Clifton Forge, Alleghany 

County, Va. 

The species Spirifer murchisoni is a plicated Spirifer, of medium to large size, having rather 

transversely extended outline, five to eight simple ribs on each side of the simple fold and 

sinus, and a characteristic strongly impressed musculature. 

I-Iinge line straight, equal to the greatest width of the shell; hinge extremities angular, generally acute, occasionally rectangular, very rarely a little rounded, occasionally slightly auriculate. The width in the brachial valve is about twice the length. In the pedicle valve, on 

account of the prominent umbone, the width is less than twice the length. 

A series of specimens shows the following dimensions: 

Dimensions of specimens of Spirijer mttrchisoni. 

No. Specimen. Length (mil- Width ( milli- Locality. limeters). meters). 

1 Brachial valve .... 17~ 38 Eastern New York (drift in Staten Island). 

2 ..... do ........... 16 . 33 Do. 

3 .. . . . do .. : ... · ..... 23 45 Glenerie, N. Y. (5122-6). 

4 . .... do ........... 15~ 30 Detroit, Maine (5112-8) . 5 ..... do ..... : ..... 22 42 Detroit, Maine (5111-6) . 6 . .. .. do ........... 18 36 Detroit, Maine (5113-6) . 7 . . ... do ........... 26~ 56 Union Springs, N. Y . Cornell University collection. 

8 Pedicle valve ..... 28 50 Do. 

9 . . . . . do ........... 16 30 . Detroit, Maine . ·Princeton collection . 10 . . . . . do .... · ....... 16~ 29 Detroit, Maine (5113-7) . 11 . . . . . do ........... 21 33 Detroit, Maine (5113-3) . 12 .. . . . do ........... 18~ 32 Detroit, Maine (5113-2) . 13 ..... do ........... 19 36 Detroit, Maine (5113-4) . 14 . .... do ........... 16(?) 35 Detroit, Maine (5113-1) . 15 ..... do ........... 16 29 Detroit, Maine ~5111-4). · 16 ..... do ........... 25 43 Detroit, Maine 5109-3). 

17 . . ... do ........... 25 44~ Eastern New York (drift from Staten Island) . 18 .. ~ .. do ........... 18 32 Do. 

19 ..... do ........... 29 56 Do. 

20 ..... do ........... 29 46 Glenerie, N.Y. (5122-1). 

2la ..... do ........... 29 '48 Glenerie, N.Y. (5121-9). 

2lb Brachial valve .... 24 48 Same shell as 21a. This represents the normal and typical 

outline. 

50245°--~0.89--16----7 
98 FAUNA OF THE CHAPMAN SANDSTONE OF MAINE. 

The two valves are about equally convex. The longitudinal profile of the pedicle valve . 

makes an unsymmetrical curve; its greatest convexity (one-fourth to one-third the length) is 

at about two-fifths the distance from beak 'to front; beak prominent, arclii.ng over the hinge 

line, strongly incurved, so that the tip is not the posterior point of the shell; cardinal area of 

medium height, curved, approaching the plane of the margin; delthyrium acute, its sides 

forming an angle of 60° or more. On the interior of the pedicle valve the teeth are well developed and are supported by dentallamellre, which occupy, as inS. cyclopterus, the second groove 

or the second plication fromthe median sinus. The shell is greatly thickened outside of the 

lamellre by a secretion of shelly matter on which. the ovarian pits are commonly strongly 

.impressed. As a result of this thickening the dentallamellre do not leave the usual incision in 

the internal mold, but the musculature, which, in the shell, is sunk in the cavity between the 

lamellre, assumes on the internal mold the character of a very conspicuous, highly elevated 

tonguelike projection, a feature which suggested the name Spirijer arrectus given· to the species 

by Hall. In the New York shells the musculature occupies usually more than half the length 

of the valve. In those from Detroit, Maine, it is proportionately smaller. The width of the 

musculature is generally .about one-fourth less than its length; the outline is ovate or pentagonal, 

with the greatest width in front of the middle. The adductor scars· are indefinable; the diductors 

are coarsely striated and ribbed longitudinally. The median sinus of ,the valve is continued 

through the musculature. There is also a fairly conspicuous pedicle cavity back of the musculature. The brachial valve is of nearly equal convexity to the pedicle valve and occasionally even a little more convex. The longitudinal profile is rather arcuate, abruptly and strongly 

incurved at the beak and elevated in front by the lingual projection of the sinus of the pedicle 

valve into the fold of 'the brachial valve. The transverse profile is low-carinate. The greatest 

depth of the valve is just back of the center and is equal to one-fourth or very commonly to onethird of the length. On the interior of the brachial valve· the thin median septum or elevated 

line extends half the length or a trifle more. The musculature is not impressed. The cardinal 

process is simple, radiately striate (12 to 15 striations may be counted on the Detroit specimens). The crural processes are not cemented to the bottom of the valve, and the incisions 

left on the internal molds by the cemented portion inS. cyclopterus are therefore not discernible 

in the internal molds of the present species. 

On each side of the simple fold ana sinus there are (in the Maine specimens) usually five or 

six, rarely seven plications; the outermost one is obsolescent, and the lateral extremities are 

smooth. The plications are strongly elevated, rounded, and broader than the interspaces. 

The sinus in the pedicle valve is low, with a broad, flat space in the bottolll. The width of the 

sinus is equal to or less than that of the two bounding ribs on each side; in many specimens the 

sinus is only as wide as one of the bounding ribs. Not uncommonly the rib bordering the 

median sinus is weaker than the adjacent ribs, and in such forms the sinus is generally narrow. 

The front of the sinus is extended as a tonguelike projection up into the fold of the brachial 

valve. This fold is strongly elevated, sometimes extremely so, depending on the amount of 

upward extension of the sinus. The fold is occasionally equal in width to the two bounding 

ribs on either side, but is commonly not quite so wide. Rarely there is a very obscure indication 

of a faint median riblet in the sinus of the pedicle valve. The finer surface ornamentation 

consists of closely set, inconspicuous concentric lamellre crossed by very fine radiating lines. 

The latter may be continuous over or .interrupted in crossing the concentric lam_ellre, depending 

on the strength of the latter. The size of the specimens from Detroit has already been indicated. 

The largest specimen (No. 16 in. the foregoing table) is 25 by 43 millimeters; the smallest specimen is 10 by 18 millimeters. 

Locality: Moose River sandstone, abundant at Detroit (locality 1100 A); also at Big 

. Brassua Lake (locality 1062 A'); both in Somerset County, Maine. No shells of the Spirijer 

murchisoni-primrevus type occur in the Chapman fauna. 

U.S. National Museum, catalogue Nos. 59741, 59742. 

Comparison with New York specimens.-The general characteristics of this common Oriskany species are well described by Hall 1 under the name Spirijer arrectus. Further descrip1 Paleontology of New York, vol. 3, p. 422, pl. 97, 1859. 
MOLL USCOIDEA. 99 

tion is giYen by Clarke, 1 with illustration of the surface markings. In Clarke's paper the propriety of recognizing the name S. · murchisoni proposed by Castelnau 2 is well stated. Clarke 

has also called attention to a paper by Scupin~ 3 in which the distribution and variation of the 

for1n are thoroughly discussed. The specimens from Detroit, Maine, present the prominent 

characters of the species but show a s1naller range of variation than is to be noticed in the 

New York specin1ens taken as a whole. 

The 60 specii:nens in the Survey collection ure in size rather below the average of specimens from the faunn.s of New York and Maryland. The largest specimen is 2.5 millimeters 

long and 43 millimeters wide. Two specimens (bra9hin.l valves) mn.y be selected as representing 

the ayerage din1ensions and Yariation: 

Specimen No. 5382-3, 37.5 millimeters wide, 28.8 millimeters long. 

Specimen No. 5382-1, 37.8 millimeters wide, 22.6 millimeters long. 

Both of these specimens are apparently undistorted by pressure. The length from beak 

.to front of pedicle valves is greater than the length of brachial valves of the same size, on 

account of the prominent overarching beak. The convexity of the valves is approximately 

the same, and the number of plications is normally six on each side of the n1edian fold of the 

brachial valve; six plicn.tions bound the sinus of the pedicle valve and occasionally there is a 

faint trace of a seventh on the cn.rdinal angle when this is extended and well. pres.erved. 

On several of the·specimens the plication next to the sinus of the pedicle valve is distinctly 

less strong and less elevated than the next n.djoining plication. The bottom of the sinus in 

well-preserved molds of the exterior is distinctly flattened for a width of about 1~ millimeters; 

otherwise all 'the plications, as well as the grooves between them, are evenly rounded. The 

median fold of the brachin1 valve is narrower and less elevated than in the New.York Oriskany 

shells, a difference due partly to smaller size. The muscular scar on the interior of the pedicle 

valve is narrower and n1ore angular than in typical forms from New York. 

The specin1ens frmn the Moose River sandstone are specifically. the same as the smaller 

specimens of S. arrectus I-Iall from the New York-Appalachian Oriskany. 

lla1'ieties of Spirifer murchisoni.-Scupin 4 has divided the American forms of Spirifer 

murchisoni into two "varieties." The first form, to which the name S. arrectus HaU 5 was 

giYen, Scupin characterized as being strongly inflated, with high, keel-like or rounded fold, 

and correspondingly deep sinus. Scupin here includes the following forn1s: 

Spirifer arrectus. Hall, Paleontology of New York, vol. 3, p. 422, .pl. 97, figs. 1 (except 1e and lf), 1859; idem, vol. 8, 

pt. 2, pl. 33, figs. 24, 26 (not fig. 25), 1893. 

Spir·~(er antarcticus. Sharpe, Geol. Soc. London l'rans., vol.. 7, p. 206, pl. 26, fig. 1, 1856. 

Spirifer orb·ignyi. Sharpe, idem, p. 207, pl. 26, fig. 3. 

'rl1e second ''yariety/' in Scupin's inter'pretation,6 includes a'' less inflated form with lower 

fold and flat sinus" and comprises the following forms: 

Spirifer antarcticus. Morris and Sharpe, Get>l. Soc. London Quart. Jour., vol. 2, p. 276, pl. 11, fig. 2, 1846. 

Sp·irifer orbi[lnyi. Morris ::mel Sharpe, idem, p. 276, pl. 11, fig. 3. 

S1)·irijer capensis. Von Buch, K. Akacl. Wiss. Berlin Abh., fig. 1, 1846. 

SJ)irifer antarcticus. Sharpe, Geol. Soc. London Trans., 2cl ser., vol. 7, p. 206, pl. 26, figs. 2 and 5 (not 1), 1856. 

SJ)ir·ifer orbiunyi. Sharpe, idem, p. 207, pl. 26, figs. 4, 6 (not 3). 

Spinfer arrectus. Hall, Paleontology of New York, vol. 3, pl. 97, figs. 1e andlf, 1859. 

Spi·rifer ch1tquisaca. Ulrich, Neues Jahrb., Beilage Band, vol. 8, .P· 65, pl. 4, figs. 19, 20, 1893. 

Spirifer antarcticus. Kayser, Deutsch. geol. Gesell. Zeitschr.", vol. 49, p. 297, pl. 9, figs. 1-4, 1897. 

To his second ''variety" Scupin applied the name antarctic'l.lS of :Morris and Sharpe. 

It so happens that these "-yarieties" are of some value, but in a sense somewhat different 

from tha.t suggested by Scupin. Th~ forms of Spirifer murch~soni from Glenerie, N.Y./ repret New York Stnte :Mus. Mom., vol. 3, p. 46, pl. 6, figs. 26-30, 1900. 

a Syst?lme sllurion dol' Amerique, p: 41, pl. 12, figs. 1, 2, 1843. 

s Deutsch. gool. Gesell. Zeitschr., vol. 50, p. 462, 1899. 4 Scupln, Huns, Ueber o.xotische, znr gruppe des Spirifer primrevus gehorige Formen: Deutsch. geol. Gesell. Zeitschr., vol. 50, pp. 462-467, 1898. 

G Sec Paleontology of New York, vol. 3, p. 97, all figures excepting figs. 1e and If, 1859. . · ' 

o Scupi.n, Hans, op. cit., p. 463. 

7 This locality has become well known through,. the efforts of Gilbert Van lngen, who has worked out a large series of silicified shells from the 

Oriskany thoro. See his report, The Oriskany fatma of Olenerie, Ulster County, N.Y.: New York State M:us. Bull. 69, pp. 1199-1208, 1903. See 

also Clnrko, J .. M., Now York State 1\fus. 1\fem., vol. 3, No.3, pp. 74-75, 1900. A suite of specimens kindly furnished by Dr. Van lngen has been of 

value In the discussion or several species in the present paper. 
100 FAUNA OF THE CHAPMAN SANDSTONE OF MAINE. 

sent typically Scupin's first form or "variety" arrectus, and the forms of Spirifer murchisoni 

from Union Springs, N.Y., represent typically his second form, var. antarcticus. In this second 

form:, however, specimens with a high fold and deep sinus, supposedly characteristic of the first 

variety are common; and vice versa, in the first form from Glenerie, many specimens with a 

lower fold and shallow sinus, supposedly characteristic of the second vari~ty, have been observed. 

The development of fold and sinus can not, therefore, be consid~red a distinctive criterion; and 

convexity of the valves is an equally or even more interchangeable character. The inadequacy 

of Scupin's distinctions between the two forms has already been indicated· by Clarke/ who 

considers "it practically certain that these d.ifferences are altogether fugitive." This conclusion 

certainly seems proper; but Scupin's two ''varieties" as indicated may be retained to some 

extent on other grounds. · "' 

The first form, or variety arrectus Hall (per Scupin), is a type characterized by oiuy five 

or six lateral plications. The outline is commonly a trifle less transversely extended than 

in the second form and the shells are commonly a trifle smaller.. This form occurs at Glenerie, 

N.Y., and in Maine, as well as at Nictau, Nova Scotia, and is characteristic of the finer-grained 

rocks. The second form, the so-called variety antarcticus of Scupin, is characterized by seven 

or eight lateral plications. This form occurs in the coarser Oriskany sediments, as at Union 

Springs, N. Y., and at Cumberland, Md. 

These two forms are not persistently sharply differentiated, at least. not sufficiently so to 

warrant distinct specific names. At most localities intermediate forms occur. At Carlisle, 

N. Y., and probably also at Schoharie, both forms occur together. The distinctions indicated 

in the present paper have been found to be more constant and valuable than those suggested 

by Scupin. The gibbosity of the shells and the depth of fold and sinus are features which not 

only have been found to vary rriost confusedly, but which are also commonly dependent on 

modes of preservation of the fossils; at best they are only incidental characters. On the. other 

hand, the number of ribs, the size, and the relative extension transversely are features of evolutional value in the Spirifers; moreover, they are not affected by conditions of preservation, 

and, most. important of all, they are least variable among specimens associated in a single 

faunule. · 

Geologic range.-Spirifer murchisoni represents a development of Spirifer which appears 

to be restricted to rocks ranging from the late Helderbergian through the Oriskany or Lower 

Coblenzian faunas. It is represented in the Lower Devonian of Europe, South Mrica, and 

South America, and practically at all places in North America where rocks of this age occur. 

In different regions different names have been given to Spirifers of this type. A close study 

of these will be of some value. · . 

·similar forms in North America.-The Spirijef cyclopterus of Hall, the ancestral form of 

Spirifer murchisoni, has already been discussed. It is typically small-er, with· rounded, less 

sharp cardinal extremities and a less transversely extended outline. On the interior the crural 

processes have been observed to be cemented to the bottom of the brachial ,valve for about 

1 millimeter inS. cyclopterus)· inS. murchisoni tlie crural processes are free. InS. 1nurchisoni 

the musculature is always deeply impressed; in S. cyclopterus typically not so. The fold and 

sinus commonly are relatively wider in S. cyclopterus than in S. murchisoni. Spirifer cyclopterus ends in the uppermost Helderberg and Oriskany, where Spirifer murchisoni begins. 

Spirifer duodenarius Hall, which also presents close affinity with Spirifer murchisoni, 

has the sharp cardinal extremities, transversely extended outline, six or seven rounded ribs, 

and strong musculature of S. murchisoni, but differs in having a narrower cardinal area in the 

pedicle valve. In the present paper attention has been called to the weakening of the rib 

bounding the median sinus and the frequent narrowness of fold aJ?.d. sinus in S. murchisoni! These are normal features of Spirifer duodenarius, in many specimens of which the 

median fold is not much wider than the bounding ribs. The musculature is a little less 

strongly impressed in S. duodenarius than in S. murchisoni. The latter begins in the upper1 Clarke, J. M., Oriskany fauna of Becraft Mountain, Columbia County, N.Y.: New York State Mus. M:em., vol. 3, No.3, p. 47, 1900. 
MOLL USCOIDEA. 101 

most I-Ielderbergian and ranges. through the faunas of Oriskany and Lower Coblenzian type; 

Spi'rifer cluodenarius is reported fron1 the Schoharie grit and Moose River sandstone and ranges 

through the '' Corniferous." 

SzJirifer hemicyclus Meek and Worthen/ from the Oriskany fauna of Illinois, has been 

regarded as a synonyn1 of Spirifer 1nurchisoni, but under this name Meek and Worthen have 

included two apparently very distinct species. 

Spirifer hemicyclus is a species of the same size and the same proportion of width to length 

as S. murchisoni, but it has ten to twelve angular rib13 on each side of the median fold and . 

sinus, c01npared with five to eight in S. murchisoni)· its cardinal area is ve!y high and almost 

perpendicular, whereas inS. murchisoni the cardinal area is of medium height and approaches 

the plane of the margin; and the width of the fold or sinus is equal to that of the three or four 

bounding ribs, compared with only two or less in S. murchisoni. However, the second form 

of Spirifer, which was doubtfully believed by Meek ancl Worthen 2 to be identical with S. hemicyclus, is quite distinct and presents the normal aspect of Spirifer murchisoni, with whi~h it 

ought to be identified. This second species should be regarded as :fi.xing the occurrence of 

Spirifer murchisoni in the beds in Illinois (Union County) which can·y Oriskany fossils. Like 

the true Spirije'l' hemicyclus of Meek and Worthen their Bpirifer engelmanni ( = Spirifer worthenanus Schuchert), which has also erroneously been regarded as an equivalent of S. murchisoni, 

is quite distinct; it seems to be remarkably similar to the European Spirifer hercynir.e var. 

primrevijo1·mis. · 

I'he shell figured by Walcott and doubtfully referred to Delthyris raricosta is a true Spirifer, 

having eight ribs on each side and the wide outline and acute extremities characteristic of 

S. murchisoni, from which it can not b.e distinguished at ,present. 

If, however, it is found to possess a lower cardinal area, it may be referred to S. duodenarius. Walcott mentions a larger series of specimens from Lone Mountain, Nev., as grading 

from S. ntricosta to S. du9denarius. 

South American equivalents of Spirifer murchisoni.-In the Lower Devonian faunas of 

the Falkland Islands, of Argentina, of Bolivia, and of Brazil are many Spirifers showll;lg more 

or less rese1nblance to Spirifer murchisoni. These Spirifers have been variously identified as 

S. ctntctrcticus, S. orbignyi, and S. hawlcinsii, all thr~e of Morris and Sh8.l'pe; S. boliviensis and 

S. q_uichuus of D'Orbigny; Spirifer chuquisaca and Spirifer sp. a of Ulrich; S. vogeli Von Aumon, 

and S. dm·byi Rathbun. Some specimens have been referred to S. duodenarius Hall or to 

S. arrectus ( = S. murchisoni). Practically all these are regarded by Scupin as forms of a single 

species, identical with Spirifer arrectus Hall ( =S. murchisoni Castelnau). 

Under the name Spirifer antarcticus Morris and Sharpe several paleontologists have grouped· 

fonns of very different aspect. The Falkland Islands Spirifer originally described as S. antarcticus 

is very large, of transversely drawn-out outline (3-2- inches wide, 1% inches long in the pedicle 

valve ~),with a very high cardinal area (five-eighths of an inch), strong musculature, ten to 

twelve ribs on each side of the deep fold and sinus, the sinus apparently equal in width to three 

or four lateral ribs, and delthyrium very narrow. This shell does not appear to belong to 

the group Spi1·ifm· 1nurchisoni, but rather to the group including S. hercynir.e Giebel and the 

American equivalents S. gaspensis Billings and S. macrothyris I-Iall. This species appears 

in South Africa, and to disentangle the synonymy of .S. murchisoni to which these forms have 

been referred the following synonymy of SzJirifer antarcticus is given. It is not to be inferred 

that all these "synonyms" represent necessarily one and the same species, but rather that 

they are closely associated in a group by themselves, apart from the murchisoni type here 

under discussion. 

1846. Spirijer antarcticu,s. · Morris and Sharpe, Geol. .Soc. London Quart. Jour., vol. 2, p. 276, pl. 11, fig. 2. 

Falkland Islands, apparently with Leptocreliaflabellites, Orthis [Chonostrophia] tenuis, etc. 

?1856. S]Jirifer antarcticus. Sharpe, Geol. Soc. London Trans., 2d ser., vol. 7, p. 206, pl. 26, figs. 1, 2, 5. 

Warm Bokkevelcl, South Africa, with Leptocreliaflabellites. 

1 Mock, P. B., llnd Worthen, A. H., Illinois Gool. Survey, vol. 3, p. 399, pl. 8, figs. 6, 7, 1868. 2 Idem, pl. s,'llgs. 7a, 7b. 
102 FAUNA OF THE CHAPMAN SANDSTONE OF MAINE. 

?1856. Spirifer orbignyi (not Morris and Sharpe). Sharpe, idem, p. 207, pl. 26, figs. 3, 4 (not 6; = Spirifer cf. S. duodenarius?). 

Warm Bokkeveld, with S. antarctil:Us. 

1903. Spirijer orbignyi (not Morris and Sh~rpe). Reed, South African Mus. Annals, vol. 4, p. 180, pl. 22, fig. 4. 

Fossiliferous. First sandstone, Bokkeveld series: South Africa. 

1903. Spirifer cf. S. pedroanus. Reed, idem, p. 183, pl. 22, fig. 5. 

Bokkeveld series: South Africa. · 

not 1897. Spirijer antarctil:Us. Kayser, Deutsch. geol. Gesell. Zeitschr., vol. 49, p. 297, pl. 9. 

Argentina. 

not 1898. Spirijer arrectus var. antarcticus. Scupiu, idem,' vol. '48, p. 464, pl. 17. 

Spirifer orbignyi Morris and Sharpe, which was brought back by Darwin from the Falkland Islands, was described as having about ten rounded plications on each si~e of the median 

sinus, but the three figures of the species show only six to eight ribs. The fold and sinus are 

equal in width to two· of the bounding ribs or less, the width is only twice the length, and there 

is a very strong musculature. The figures show a species very similar to Spirifer murchisoni, 

if not identical with it. In the description, however, the species is·mentioned as having a low 

cardinal area, a feature which would associate the specimens rather with S. duodenarius. As 

the description refers to a species with ten lateral ribs on each side (which is mor~ than ever 

occur in either S. murchisoni or S. duodenarius); S. orbignyi as described by Morris and Sharpe 

must be regarded as a distinct species. These authors mention a faint groove in the fold o.f 

the brachial valve, which is not, however, figured. It is very unfortunate that the figures of 

the species indicate a form quite different from that suggested by the description. The South 

African Spirifers)dentified by Sharpe and by Reed asS. orbignyi appear to belong to different 

speCies. Reed's figure indicates a Spirifer of the S. ga.spensis-macrothyris-hercynire-antarcticus 

type. 

Spirifer chuquisaca ffirich is probably the same asS. boliviensis, a form meagerly described 

and figured by D'Orbigny. The species is characterized by a very high cardinal area, which 

is only slightly concave and which approaches the plane of. the margin. The width is twice 

the length, the cardinal extremities are acute, and the front-lateral margins are evenly curved. 

The number of ribs on each side averages about six, but increases to seven or eight in the 

larger specimens. The fold and sinus are very deep, and the fold is sometimes grooved. From 

Spirifer murchisoni this species can easily be distinguished by its higher cardinal area and 

narrower delthyrium, which is less than 60° in the Bolivian species. In the high cardinal area 

S. chuquisaca resembles S. antarcticus, with which it is commonly regarded as a synonym; 

it is, however, a very distinct form of less transversely extended outline. Moreover, the Bolivian species has only six, seven, or eight lateral ribs; Spirifer antarcticus has ten or twelve 

ribs, with narrower interspaces. 1 

Spirifer hawkinsii Morris and Sharpe has been regarded as a very close ally of Spirifer 

murchisoni and is the type of what Scupin has called a third variety of Spirifer arrectus. This 

third" arrectus" type resembles the first in having only five or six lateral ribs but was supposed 

to differ by the lesser elevation of the fold, shallower sinus, and less gibbous convexity. The 

original species of Morris and Sharpe is a transversely elongated Spirifer of the general S. 

murchisoni proportions and outline but has only four or five lateral ribs. In the original 

description the brachial valve is described as having "five imbricated ribs on each side [four 

or five shown in figure], the two middle ones acute, prominent, and nearly equal to the mesial 

ridge, which is slightly furrowed; the lateral ribs diminish in importance as they approach the 

edge; intervening furrows rather wider than the ridges and rounded." In the cast of the 

pedicle valve the musculature is. strongly impressed; only three or four ribs on each side are 

noted. Except that Morris and Sharpe record a groove in the median fold/ this typical form 

of Spirifer hawkinsii approaches the Maine shells described in the present-paper as Spirifer 

sparsus Clarke. 

In the Lower Devonian of Argentina occurs a shell (Spirifer antarcticus (not Morris and 

Sharpe) Kayser 3) that is similar to Spirifer hawkinsii in having only four or five ribs, which 

I Morris and Sharpe's figures show only about eight ribs inS. antarcticus on each side, but their description mentions ten or twelve. 

2 The extent of persistency of this groove or furrow in the median fold of Spirifer hawkinsi is unknown. It does not appear to be constant. 

a Deutsch. geol. Gesell. Zeitscbr., vol. 49, p. 297, pl. 9, figs. 1, 2, 4 (not fig. 3, which is probably S. chuquisaca). 
MOLL USCOIDEA. 103 

increase in width toward the middle, but this shell (fig. 1 of Kayser) lacks the "mesicostulate" 

characteristic on fold and sinus and varies toward a shell with five or six plications (fig. 2 of 

Kayser) almost identical with the Bolivian fossils called Spirifer sp. a Ulrich 1 and Spirifer 

quichuus D'Orbigny, 2 as well as with the formS. murchisoni occurring at Nictau, Nova Scotia. 

These shells appear to conform with the pauciplicate variety of Spirifer murchisoni. If they 

are really the same spe~ies asS. 1nurchisoni the nameS. quichuus D'Orbigny will take precedence 3 overS. 1nurchisoni Castelnau and S. arrect·us Hall; but present knowledge of these South 

American fossils is not sufficient to warrant definitely replacing the nameS. murchisoni. 

SouthAfricanSpi1V'e?'8 of the type ofSpirifermurchisoni.-One of the earliest described South 

African Spirifers, Spi?tfer capensis Von Buch,4 has always been regarded as a very close ally 

of Spirifer· 1nurchisoni and the Falkland Islands SzJirifer. antarcticus. · The species has an 

inflated, very convex umbo in the pedicle valve, a high arched ~ardinal area, and delthyrium 

about 60° or less; the umbo in the brachial valve is also rather inflated and arched over the 

hinge line (according to Von Buch'.s figures); the musculature is strongly impressed. Von 

Buch mentions eight or nine broad,. rounded ribs each side of the fold and sinus, although his 

figures show ten or eleven. The ribs are rounded, with narrower interspaces; fold and sinus 

rounded, not keeled, very broad. Von Buch states that the sinus is equal in width to onesixth the width of the shell; his figures show the fold and sinus to be equal to three ribs in width, 

and less than a fourth the width of the shell. Scupin, who has examined Von Buch's originals 

in the Berlin Museum fur N aturkunde, states that the sinus is equal in ·width to four and onehalf of the bounding ribs. Spirifer capensis Von Buch n1ay be distinguished from S. muTchisoni by its more numerous ribs, higher cardinal area, and wider fold and sinus, and in these 

respects it corresponds with S. antarcticus, differing from that species in its less transversely 

extended outline. InS. antarcticus the ratio of width to length is over two to one and in the 

brachial yalve is three to one; inS. capensis the ratio of width to length is five to three and in 

the brachial valve a shade over two to one. From bo.th Spi?"ifer murchisoni and S. antarcticus, 

Spirifer capensis differs in having the umbones inore inflated and overarching in both valves. 

. Spirifer capensis was originally collected by M. Kraus, of Stuttgart, from Kokman's Kloof 

in Zwellendam, Cape Colony, where a whole stratum of sandstone is almost composed of these 

Spirifers. Although the species would thus seem to be one of the most abundant Spirifers in 

the Bokkeveld ( n series, where this sandstone stratum probably· belongs, no Spirifer since 

recorded from South Afi'ica is strictly conforn1able with Von Buch's figures and description. 

I-Iis figures ar~ imperfect, and reillustration and fuller description of these Zwellendam specimens are highly desirable. 

Although 110 Spirifer since recorded froni South Africa has the inflated gibbous overarching 

umbones and the yery wide fold and sinus shown in Von Buch's figures of S. capensis, the prevnili~lg Spirifers in tp.e Bokkeveld series as reeorded by Sharpe 5 and by Reed 6 agree with 

Von Buch's species in the rather low rounded ribs a;nd rounded fold and sinus; comn1only 

eight or nine, rarely ten ribs on each side; proportion of width to length 2:1 or slightly more 

in the brachial valve and less than 2:l(as low as 3:2) in the pedicle valve; a very high cardh1al 

area, and delthyrium less than 60°. 7 Fron1 a c01np~rison of son1e figures and imperfect specimens it would be almost i1npossible to separate from S. murchisoni a brachial valve of these 

Boldmveld Spirifers with eight laternl ribs, such as that shown in Sharpe's figure 4 or in Scupin's 

figure, or a pedicle V'tl.lve like that shown in Shnrpe's figure 5, which might almost be considered 

a figure of so1ne New York specilnen of S. mu?·chisoni. Furthermore, accordh1g to Reed's 

1 Nouos Jubrb., 1892, p. G7, pl. 4, fig. 22. Totora, Brazil, occurring with Leptoccelia flabellites. 

2 Voyage dliDS l'Ameriquo m~ridionale, Pal~ontologie, p. 37, pl. 2, fig. 21, 1842. Chuquisaca, Bolivia. 

s Schuchart (U.S. Geol. Survey Bull. 87, p. 398, 1897) gives Ulrich's Spirifer sp. a as a synonym of S. murchisoni. Ulrich's form seems identical 

with ])'Orbigny's S. quichuus, and these fossils are also apparently identical with the specimens figured by Scupin from Chuquisaca (Deutsch" 

gool. OescH. Zeitschr., vol. 48, pl. 17, fig. 1, 1898) and from Tela (idem, fig. 5). 

4 Ubcr Spiri/er keilhavii, i.iber dessen Fundort und Verhii.ltniss zu ii.hnlichen Formen: K. Akad. Wiss. Berlin Abh., vol. 11, pp. 76-80, pl., 184G. 

o Ocol. Soc. London Trans., 2cl ser., vol. 7, 185G. 

o South African Mus. Annals, vol. 4, 1903. 7 See Sharpe, Daniel, Oeol. Soc. London Trans., 2d ser., vol. 7, pl. 26, figs. 1-5 (not fig. 6) 1856. These figures are now known to represent only 

a single spocios, not two (S. a11tarcticus and S. orbignyi), as stated by Sharpe. See also Scupin, Hans, Deutsch. geol. Gesell. Zeitschr., vol. 49, 

pl. 1i,.figs. 4a, 4b, 1898. Reed, F. R. C., South AfricllJl Mus. Annals, vol. 4, pp. 180-182, 1904. 
104 FAUNA OF THE CHAPMAN SANDSTONE OF MAINE. 

descriptions, these South African Spirifers have· most commonly sixteen ribs, eight on each side; 

son1e have as few as twelve, thus corresponding with S. murchisoni; and the number never 

exceeds eighteen. Unfortunately Reed's only figure 1 shows eleven ribs on one side-there 

were probably twelve or thirteen-and on Sharpe's figures 2 there are not less than nine lateral 

ribs on any· of the specimens, and on some there are as many as ten or eleven on each side. 

Not only do these South Mrican Spirifers differ from Spirijer murchisoni in the larger number 

of ribs (8. murchisoni never has more tha.n eight distinct ribs on each side), but they have also 

a much greater cardinal area. They differ from Spirijer antarcticus in the smaller. number 

of ribs and less tra;nsverse outline, a;nd from S. orbignyi, with which they have also been identified, in the higher cardinal area. From S. chuquisaca they differ chiefly in the shallower 

fold and sinus and the lower ribs with narrower interspaces. It is probable that a careful 

study of the types of Von Buch will show that the South Mrican Spirifers just mentioned are 

identical with S. capensis, which may be considered a distinct species. 

European relatedforms.-In the European faunas the species which n1ost nearly approaches 

Spirifer murchisoni isS. primrevus, the characteristic fossil of the Taunusian Siegen graywacke. 

This zone has been regarded as the European representative of the Oriskany of America; so 

that we might expect some degree of identity in the importa.nt diagnostic species of Spirifer. 

S. primrevus 3 differs, however,. from S. murchisoni in being less transverse and in having 

eight or very commo.nly .nine or ten lateral ribs, whereas in S. ~n'urchisoni the number of ribs 

o.n each side is from five to eight. · 

SPIRIFER cf. S. DUODENARIUS (Hall). 

Plate IV, figures 3, 4. 

1843. Delthyris duodenaria. Hall, Geology of New York, Rept. Fourth Dist., p. 172, fig. ·5. 

Corniferouslimestone: 5 miles east of Buffa.lo, N.Y. 

1856. Spirifer orbignyi .(pars) (not of.Morris and Sharpe, 1846). Sharpe, Geol. Soc. London Trans., 2d ser., vol. 7, 

p. 207, pl. 26, fig. 6 (not figs. 3, 4). · 

Hard gray siliceous rock:. Warm Bokkeveld, South Africa. 

1831. Spirijera duodenaria. Billings, Canadian Jour., vol. 6, p. 256, figs. 65-67. 

Devonian (Corniferous): Rama's farm, near Port-Colborne, and at Woodstock, Canada West. 

1863. Spirifera duodenaria. Billings and Logan, Geology of Canada, pp. 372, 428, fig. 394. 

Corniferouslimestone: Famine River, Quebec. 

1867. Szn:rijera duodenaria. Hall, Paleontology of New York, vol. 4, p. 189, pl. 27, figs. 13-16, pl. 28, figs. 24-33. 

Schoharie grit: Eastern New York. · 

Corniferous limestone: Throughout New York, in Canada West, and in Ohio. 

1879: Spirijera duodenaria (?). Rathbun, Boston Soc. Nat. Hist. Proc., vol. 20, p. 25. 

Lower Devonian sandstone: Rio Maecuru, Para, Brazil. 

1883. 8pirifera duodenaria. Hall, New York State Geologist Second Ann. Rept., pl. 58, figs. 8-13. 

Schoharie grit: Schoharie County, N.Y. 

Corniferous limestone: Western New York. 

1884. Spirifer cf. 8. duodenarius. 4 Walcott, U. S. Geol. Survey Mon.' 8, p. 135, ?pl. 14, fig. 12 (not pl. 4, figs. 2, 2a). 

Lower Devonian limestone: Lone Mountain, 18 miles northwest of Eureka, Nev. 

1889. Spirifera duodenaria. Nettelroth, Kentucky fossil shells, p. 114, pl. 12, figs. 12, 13, 16. 

Corniferous limestone: Kentucky and Indiana, about the Falls of the Ohio. 

1893. Spirifer duodenarius. Ha.ll and Clarke, Paleontology of New York, vol. 8, pt. 2, pp. 19, 37, pl. 33, figs. 8-15. 

Schoharie grit: Schoharie County, N.Y. · 

Corn,iferous limestone: Western New York. 

1897. Spirifer duodenarius. ·Weller, Jour. Geology, vol. 5, pp. 627, 629. 

Upper Helderberg limestone: Devils Bake Oven, near· Grand Tower, Jackson County, Ill. (Nos. 4 and 11 of 

section). 

1897. Spirifer duodenarius. Schuchert, U. S. Geol. Survey Bull. 87, p. 388. 

Upper Helderberg: New York; Ontario; Columbus, Ohio; Falls of the Ohio; Rio Maecuru, Para, Brazil. 

1898. Spirifera duodenaria. Bownocker, Denison Univ. Sci. Lab. Bull., vol. 11, p. 11, pl. 7. 

Corniferous limestone: Delaware, Marion, and Kellys Isl:.tnd, Ohio. 

1899. Spirijer duodenarius. Prosser, New York State Geologist Seventeenth Ann. Rept. (for 1897), pp. 352, 353. 

Schoharie grit and Corniferous limestone: Oniskethau Creek, Albany County, N.Y. 

1 Reed, F. R. C., op. cit., pl. 22, fig. 4. 

2 Sharpe, Daniel, op. cit., pl. 26,.figs. ~-5, not fig. 6. 

s See Scupin, Hans, Die Spiriferen Deutschlands, pp. 84-86, pl. 8, fig. 9, 1900. 

4 De~cribed and figured asS. raricosta Conrad. 
MOLLUSCOIDEA . 105 

. 1900. S7Jirijer duodenarius. Kindle, Indiana Dept. Geol. and Nat. Res. Twenty-fifth Ann. Rept., p. 647, pl. 9, fig. 10. 

Sellersburg 1 [?error for Jeffersonville] limestone: Falls of the Ohio and Charlestown, Incl. 

1903. Spirijer duodenarius. Katzer, Geologie.des unteren Amazonasgebietes, p. 194, pl. 10, figs. 3a, 3b. 

Upper Helderberg: Rio Maecuru, Para, Brazil. 

'£hit:l Onondaga species does not occur in the Chapman fauna but is present in the fauna of the 

Moose River sandstone occurring at Big Brassua Lake, Somerset County. It is a medium-sized 

Spirifer with straight hinge line, width equal to about twice the length, acute hinge extremities, 

and six or seven rounded ribs with narrower interspaces on each side of the simple, narrow, 

rounded fold and sinus; both valves are subequally convex. The species is distinguished from 

S. murchisoni ohiefly by the low cardinal area of the pedicle ·valve, which is only slightly higher 

than that of the brachial valve. Figure 3 of Plate IV shows a fragment of a brachial valve 

(enlargecl2 diameters)'With a distinct cardinal area, in which the cardinalprocessisradiallystriate, 

but this is not inclicn.ted in the figure. The second specimen (fig. 4) is a pecli9le valve in which the 

cardinal area is but slightly greater than that in the brachial valve shown in figure 3. This species 

is a characteristic fossil of the Onondaga '("Corniferous") limestone of New York. It ranges 

throughout the Schoharie grit and Onondaga limestone and has not been reported below the 

Schoharie. Its occurrence in a belt of rooks which has heretofore been considered to represent 

the Oriskany is therefore of some importance. Its appearance in the Spirijer arenosus fauna in 

central northern Maine is suggestive of later persistence of that fauna than in the New York 

area, a suggestion which is in harmony with the evidence brought out by the breccias of St. 

I-Ielens Island ah·eady referred to (p. 83). In this connection may also be mentioned the 

occurrence of the "Corniferous" species Chonetes (Eodevonaria) arcuatus and Chonetes vicin'lf,s 

at Little Brassua Lake. 

Locality: Moose River sandstone: Bjg Brassua Lake (locality 1062 A'), Somerset County, 

Maine. 

U. S. National Museum, catalogue No. 59'(43. 

SPmiFEH. SPAH.sus Clarke. 2 

Plate I, figures 11, 13, 14, 15, 17, 21, 22, 24; Plate II, figure 17; Plate IV, figure 2. 

cf. 1874. Spirifer raricosta. Billings, Paleozoic fossils, vol. 2, pt. 1, p. 47, pl. 3, fig. 5. 

Gaspe limestone No. 8 [Oriskany]: Grand Greve, Gaspe Bay, Quebec. 

cf. 1884. Spirifera raricosta. Walcott, U. S. Geol. Survey Mon. 8, p. 135 (pars), pl. 14, fig. 12; pl. 4, .fig. 2a (not fig. 2, 

which represents a Spirifer of the S. murchisoni type). 

Lower Devonian limestone: Combs Peak, and at Lone Mountain, 18 miles northwest of Eureka, Nev. 

1907. Spirifer cymindis var. sparsa. Clarke, New York State Mus. Bull. 107, p. 257, figs. 

Lower Devonic: Presqlie Isle Stream, Chapman Plantation, AroostQok County, Maine. 

A pauciplicate, trapezoidal Spirifer of medium to small size;. with broad, straight hinge line; 

t·ounded extremities; and three to five plications on each side of the strong fold and sinus-the 

inner three plications of each side strong, the outer one or two weak when present a1; all. Hinge 

line lon,g, straight, varying in length from five-sixths to very nearly equal the greatest width of 

the shell. The width in the pedicle valve varies from one-sixth to one-half greater than the 

lC'ngth. I-Iinge extremities rounded, sometimes broadly so, sometimes nearly rectangular, 

.but never sharp, acute, nor auriculate. Pedicle valve gibbous with broad, inflated, overarching umbone. Greatest depth is over the hinge line, one-third the distance from beak to 

front, where it is one-hall tq one-third the length of the valve. The transverse profile is arcuate 

with rather depressed sides. Cardinal area in the pedicle valve· of medium height, strongly 

arched, inclined at an angle of 135° or more from the plane of the margin of the valve. ' . 1 ln tho lists of fossils Wldor localitios S. duodenarius is not mentioned. As both the Jeffersonville ("Corniferous") limestone and the Sellersburg 

lfmostono (of Hmnllton ago) occur at tho places named, and asS. duodenarius bas never before been found above the'' Corniferous," it is probable 

that JofforsonvJllo ("Corniforous") is intended instead of Sellersburg limestone. If the species really occurs in the Sellersburg, this is the first and 

only occmnmco, so fur· us known, in tho Middle Devonian. Mr. Kindle informs me that the specimens of S. duodenarius referred to above were 

collected by 0. K. Greeno from residual clays but showed the peculiarities of fossilization which can be pretty definitely relied upon to distinguish 

fossils or tho slllcoous Sollers burg from tho nonsiliceous Jefl'erson"\rille limestone. . 

(In tho mo.nuseript or tho present paper this species wus already figured and described under the name Spirijcr chapmani when Clarlre's name 

· S. cyminclls var. sparsa wus published. On comparison there scenis to be no doubt us to tho identity of the two forms. 
106 FAUNA OF THE CHAPMAN SANDSTONE OF MAINE. 

Delthyrium acute, 60° to nearly 90°. On the interior of the pedicle valve d~nta!' lamellre 

are well developed and occupy the first plications-rarely the first fold-on each side of the median 

sinus. The musculature is inconspicuous, except in old shells, and the cavity outside the dental 

lamellre is not filled in; hence in internal molds the characteristic incisions of the lamellre are 

present. The musculature reaches the midlength. No median septum is observed in the 

pedicle valve. , 

The brachial valve is convex, but much less so than the pedicle valve. The greatest depth 

is near the midlength and is equal to two or three tenths of the length; the cardinal area 

is linear. On the interior of the brachial valve the cardinal process is radially striate as in 

S. murchisoni. The dent~l sockets show obscure indications of" crenulation in the only specimen in which the sockets have been observed. The "median septum" of the brachial valve 

is extremely faint. On each side of the simple fold and sinus are three strong ribs; and 

commonly there are one or two additional, more· or less obsolescent ribs which do not quite 

reach the beak. The sinus is deeply excavated, rather flat in the bottom, equal to about two 

(always less than three, rarely only a little more than one) of the bounding ribs, in width, and 

in.ore or less strongly extended as a tonguelike projection toward the fold of the opposite valve. 

The fold is strongly elevated, rapidly expanding toward the front and equal in width to about 

two of the bounding ribs in two small shells only slightly Wider than each bounding rib, in one 

equal to two ribs and in another nearly equal. The ribs are rounded and, on shells showing 

the sUrface, appear of medium height with narrower interspaces. On internal molds they are 

strongly elevated, frequently subangular, and the interspaces are equal to or much wider than 

the ridges. The finer surface ornamentation consists of concentric sublamellose lines, sometimes lamellar and ~roweled toward the front; the specimens do not show the coarse radial 

lineation of the type of S. macropleurus, etc., which the specimens sometimes resemble, and 

they are not well enough preserved to show any such fine radial lines as those of S. murchisoni 

or S. cyclopterus. No such radial lines are recorded by Clarke. 

Shell structure fibrous, impunctate under a hand lens. The largest specimens observed 

(two pedicle valves) are 21.5 by 29 millimeters and 21 by 28 millimeters; the smallest specimen 

observed (a brachial valve) measures about 10 by 15 millimeters; most of the specimmis measure 

about 15 by 25 millimeters. 

Locality.-Chapman sandstone: Edmunds Hill, also 2! miles west of Presque Isl~ Stream, 

Chapman.Township, Aroostook County, Maine. · 

U.S. National Museum, catalogue Nos. 59744 to 59746. 

Oomparisons.-This species strongly resembles 'in external aspect the Spirijer (Delthyris) 

raricosta of Conrad· and authors, but that species belongs to the genus Delthyris, having a strong 

median septum in the pedicle valve, while not the slightest indication of such a structure is 

present in S. sparsus. D. ·raricosta has commonly only two ribs on each side, and only very 

rarely three. S. sparsus ha~ never less than three ribs on each side, and commonly four or 

five. Delthyris raricosta was described from the "Corniferous" limestone, of which it is a 

characteristic and widespread fossil. · , 

Shells agreeing in external aspect with Delthyris raricosta have been recognized in the Gaspe 

'limestone 1 and in the middle Helderbergian, of Square Lake, Maine, Spirifera. raricosta? 

Conrad (S. hesione Billings nom. nov.). 2 In neither of these forms is a median septum noted 

or figured in the pedicle valve, so that they resemble Spirifer sparsus in.that respect. The 

Square Lake form (Spirifer hesione Billings) has only two broadly undulating ribs on each side of 

the fold and sinus, corresponding closely with Vanuxem's Spirifer undulatus (=D. raricosta) 

superficially; it is quite distinct from S. sparsus. The Gaspe Spirifera raricosta of Billings 

has three or four ribs and may possibly prove to be identical with S. sparsus. Clarke. Spirifer 

ilsce Kayser,3 from the lowest Devonian of the Harz, at Klosterholtz, also bears a strong resem-

. blance to S. sparsus (compare Pl. I, fig. 14; Pl. IV, fig. 2), having a broad fold and sinus, rounded 

1 Billings, Elkanah, Paleozoic fossils, vol. 2, p. 47, pl. 3A, fig. 5, 1874 (Spirifera raricosta). 

2 Billings, Elkanah, Portland Soc. Nat. Hist:Proc., vol.1, pt. 2, p.l17, plate, fig.17. 

a Kayser, Emanuel, Die Fauna der ii.ltesten Devon-Ablagerungen des Harzes, p. 162, pl. 22, figs. 3, 4, 1878. 

,, 

I 
MOLLUSCOIDEA. 107 

extremities, and only three to five· ribs on each side; but the fold in Spirifer ils::e is much more 

highly elevated and more keeled than that inS. s1Ja-rsus. 

S1Ji1'ijer hawkinsii :Morris and Sha.rpe, collected by Darwin from the Lower Devonian of the 

Falkland Islands, has already been mentioned as· resembling S. sparsus in having four or five 

ribs, but it differs in the n1ore transverse outline, sharp a~ute extremities, strong musculature, 

and grooved fold. . 

The shells figured by Walcott from the Lower Devonian of N'evada and doubtfully identified with Delthy1'is ra1'icosta are very closely related to and possibly identical with S. sparsus. 

As was emphasized by Walcott, tllis Nevada Spirifer has no median septun1 and hence can not 

be congeneric with Delthyris raricosta. The proportions are approximately the same as in S. ' 

81Ja?'S'I.ts, and the characteristic ribbing is precisely the same-a highly elevated fold and deep 

sinus, with four or five ribs on each side, the tlll'ee inner ribs very strong, the two outer ones 

narrow and obsolescent. The only apparent distinction between S. sparsus and the form shown 

by Walcott's figures is that the latter appears to have slightly more acute hinge extremities. 

Walcott's figure 2, Plate IV, indicates a Spirifer which may be referred with little, 'if any, hesitation to S. murchisoni. 

SPIRIFER GASPENSIS Billings. 

Plate IV, figure 7. 

?1837. "Terebratulre." Jackson, First report on the geology of the State of Maine, p. 128, pl. 1, fig. 10. 

Gmywacke period: Maine. 

cf. 1840. Spirifer antarcticus. Morris and Sharpe, Geol. Soc. London Quart. Jour., vol. 2, p. 276, pl. 11, fig. 2. 

Devonian: Falkland Islands. 

cf. 1850. S]Jirifer pollens (not Barrande). F. A. Roemer, Beitrage zur geologischen Kenntniss des nordwestlichen 

Harzgebirges, p. 58, pl. 9, fig. 10 (young). 

Formation and locality not given; in the Harz Mountains, Germany, probably Klosterholtz. 

cf. 1853. S]Jin"jer ]Jaradoxus (not Schlotheim). Schnur, Palaeontogra.phica, vol. 3, p. 198, pl. 32B, figs. 1b, 1c (1a.? 1d ?). 

Graywacke: Everywhere in the Eifel, Ger~any. 

cf. J858. S]Jirijer hercynir.e. Giebel, Die silurische Fauna des Unterharzes, p. 30 [of separate], pl. 4, fig. 14 (young). 

Silurian: Magdesprung, Harz Mountains, Germany. 

1863. Spirijera gasJJensis. Billings and Logan, 1 Geology of Canada., pp. 398, 410·. 

Gaspe sandstone [York River]: Douglastown River, and on the north side of the inner basin at Gaspe, Quebec. 

1865. Spi1-ijer ?nacro]Jterus (not Goldfuss). Roemer, Deutsch. geol. Gesell. Zeitsch.r., vol. 17, p. 592, pl. 17, fig. 6. 

Graywacke: West slope of the Altvater Mountains, Moravia, Austria. 

?1808. Spi1-ije1· engelmanni (not Meek, 1860). Meek and Worthen, Paleontology of Illinois, vol. 3, p. 398, pl. 8, fig. 5. 

?1868. Spirije1· hemicyclus (pars). Meek and Worthen, idem, p. 393, pl. 8, fig. 6. 

Oriskany: Union County, Ill. 

1870. Spi1-ijer macropterus (not Goldfuss). F. Roemer, Geologie von Oberschlesien, pl. 1, fig. 3. 

Wurbcnthal quartzite: Einsiecller, Durrberg, half a mile from Wurbenthal, Austrian Silesia. 

1871. Spirijer JJarado:~.-us (not Schlotheim). Kayser, Deutsch. geol. Gesell. Zeitschr., vol. 23, p. 314. 

Taunusian: Between Oberstadtfeld and Niederstadtfeld, near Daun, in the Eifel, Germany. 

1874. Spi1·ijera gaspensis. Billings, Paleozoic fossils, vol. 2, pt. 1, p. 44, pl. .3, fi~s. 8, Sa, Sb. 

Gaspe [York River] sandstone: Gaspe Bay, Quebec. 

Gaspe limestones: Split Hock, Perce, Quebec. 

?1876. Spirifer macropterus (not Goldfuss). R.ibbentrop, Naturhist. Ver. preuss. Rheinlande und Westphalens Corr.-

131., vol. 33, p. 103. 

HundsrUckian: Between Nerother Kopf, Oberstadtfeld, and Salm, in the Eifel, Germany. 

1878. Spirijer hercynir.e. Kayser, Abh. zur Specialka.rte von Preussen, etc., vol. 2, pt. 4, p. 168, pl. 23, figs. 7-~3; pl. 

34, fig. 3 .. 

Hercynian limestone: Magdesprung, Zorge, ·wilda, and Ilkenbmg, in the Harz Mountains, Germany. 

1878. S]Jirijera nictauensis. Dawson, Acadian geology, 3d eel., p. 499, fig. 176 (also 4th ed., 1891) . 

. Oriskany iron ore and slates: Nictau, Nova Scotia. 

1879. Spirijera nictauensis. Dawson, Canadian Naturalist, new ser., vol. 9, p. 3. 

Oriskany iron-ore beds and coarse slates: Nictau, Nova Scotia. 

1879. Spi1-ijera buarquiana. · Rathbun, Boston Soc. Nat. Hist. Proc., vol. 20, p. 28. 

Devonian: Hio Maecuru, Para, Brazil. 

?1880. Spi1-ijer paradoxus (not Schlotheim). Gosselet, Esquisse geologique du Nord de la France, p. 75, pl. 2, fig. 25; 

cet. excl. 

Montigny graywacke: Montigny-sur-Meuse, Amberloup, near St. Hubert, La Roche, Houffalize, Sugny, etc., 

Belgium and northern France. 

lAlso (p. 393) from Gaspe limestone No.8 at Gaspe, as Spirifera sp. indet. 
108 FAUNA OF THE CHAPMAN SANDSTONE OF MAINE. 

1883. S,pirifera gaspe:nsis. Ells, Canada Geol. Survey Rept. Progress for 1880-1882, pp. 9DD, 14DD. 

Upper Gaspe limestone (Oriskany): Perce Rock, Indian Cove, Grande Greve, and Little Gaspe; Gaspe Bay, 

Quebec. 

1885. Spirifera gaspensis. Ells, idem for 1882-1884, pp. 23E, 24E. 

Gaspe [York River] sandstone: Miners Brook branch of Cascapedia River, Gaspe Peninsula, Quebec. 

Ga.Spe Oriskany (whether limestone or sandstone not.stated): In hills back of Gaspe village, Quebec. 

1886. Spirifer cf. S. hercynire. Gosselet, Soc. geol. ·du Nord Annales, vol. 13, p. 298. 

Hundsriickian (Montigny graywacke): La Roche, Belgium. 

?1887. Spirifera sp. indet. Ami, Canada Geol. Survey Ann. Rept., new ser., vol. 2, p .. 9N. 

Oriskany slates and sandstones: Campbell River, near mouth of Don River, New Brull8wick. 

1889. Spirifer paradoxus var. hercynire. Barrois, Soc. geol. du Nord Mem., vol. 3, p. 132, pl. 9, fig. 1. 

Erbray limestone: Erbray, Loire Inferieure; France. 

1889. Spirifer dunensis. Kayser, K. preuss. geol. Landesanstalt· Abh., neue Folge, Heft 1, p. 33, pl. 15, figs. 3, 4, 5, 5a. 

Lower Coblenzian: Daun, in the Eifel, Germany. 

1889. Spirijer paradoxus mut. prrecursor. Frech, Deutsch. geol. Gesell. Zeitschr., vol. 41, p. 194. 

Lower Coblenzian: Stadtfeld, near Daun, in the Eifel; Zell8chiedan der Kyll, 1 a few miles from Gerolstein; and 

about Siegen, Germany. 

1889. Spirifer phalrena. F. von Sandberger, Uber die Entwickelung der unteren Abtheilung des devonischen Systems in Nassau, p. 105, pl. 3, figs. 3, 3a. 

Lower Spirifer beds (Lower Coblenzian): Stadtfeld., near Daun and other localities in the Eifel, Germany. 

Vireux sandstones: Vireux, Ardennes, France (S. paradoxus Gosselet, 1880). 

1891. Spirijer dunensis. Kayser, Lehrbuch der geologischen Formationskunde, p. 83, pl. 12, fig. 6. 

Lower Coblenzian coarse graywacke: Stadtfeld, etc.; in the Eifel, Germany. 

1897. Spirijer hercynire. Frech, Lethrea Paleozoica, pl. 23 A, figs. 5a, 5b. 

Lower Coblenzian ("zone of Spirijer hercynire"): Oberstadtfeld, in the Eifel, Germany. 

1897. Spirifer buarquianus. Schuchert, U.S. Geol. Survey Bull. 87, p. 383. 

Middle Devonian 2 : Rio Maecuru, Para, Brazil. 

1897. Spirijer gaspensis. Schuchert, idem, p. 391. 

Oriskany: Gaspe. 

1897. Spirijer nictauensis. Schuchert, idem, p. 399. 

Oriskany: Near Nictaux, Nova Scotia. 

?1899. Spirijer paradoxus. Collins, Roy. Geol. Soc. Cornwall Trans., vol. 12, p. 239. 

Lower Devonian [Siegen, or more probably Lower Coblenzian]: Fowey, Cornwall. 

1900. Spirifer hercynire. Scupin, Paleontol. Abh. (Dames & Koken), new,ser., vol. 4, pt. 3, p. 290, pl. 21, :figs. 4, 5a, 5b. 

Lower Coblenzian: Along the Rhine, at Stadtfeld, near Daun, St. Johann, and Landscheid, Germany. 

Lower Coblenzian quartzite: Bienhorn Valley, near Ehrenbreitenstein, Germany. 

Ahrien beds: Belgium. · 

Erbray limestone: Erbray, France. 

Lower Coblenzian: In the Kellerwald, Germany. 

Middle Eo-Devonian: Harz Mountains, Germany. 

Wiirbenthaler quartzite: '\Vurben Valley, Germany (Austrian border). 

1900. Spirifer hercynire var. primrevijormis. Scupin, idem, p. 292, pl. 31, :figs. 3, lOa-c. 

Lower Coblenzian: Vallendar and Bienhorn Valley, Germany. 

1902. Spirifer hercynire. Drevermann, Palaeontographica, vol. 49, p. 95. 

Lower Coblenzian: Oberstadtfelcy near Daun, in the Eifel, Germany. 

1903. Spirijer buarquianus. Katzer, Geologie des unteren Amazonasgebietes, p. 272, pl. 10, :fig. 1. 

Upper Helderberg: Rio Maecuru, Para, Brazil. 

1903. Spirifer buarquianus var. contracta. Katzer, idem, :fig. 1a. 

Upper Helderberg: Rio·Maecuru, Para, Brazil. 

1903. Spirijer buarquianus var. alata. Katzer, idem, :figs. ld, 1e . 

. Upper Helderberg: Rio Maecuru, .Para, Brazil. 

1904. Spirijer orbignyi (not Morris and Sharpe). Reed, South African Mus. Annals, vol. 4, pt. 3, p·. 180, 3 pl. 22, fig. 4. 

Lowest fossiliferous sandstone, Bokkeveld series: North of Montagu, South Africa. 

?1904. Spirifer cf. S. pedroanus (not Hartt). Reed, idem, p. 183, pl. 22, fig. 5. 

Lowest f9ssiliferous sandstone, Bokkeveld series: 3 miles southeast of Triangle; north of Homestead; Uitkomst; 

Gydo Pass; Witzenberg Valley; and point just north of Stinkfontein, Ceres, South Africa. 

L905. Spirifer gaspensis. Clarke, New York State Mus. Bull. 80, p. 145. 

Perce limestone: Perce Rock, Perce, Quebec. 

Gaspe sandstones: Gaspe Bay, Quebec. 

1 Also called Densbom, or St. Johann. 

2 This,fauna is probably of Onondaga or Coblenzian (upper Eo-Devonian) age, not Meso-Devonian. 

a The description here indicates a Spirifer of the type of S. capensis, which has been discussed under S. murchisoni. The figure, however, represents a very different species, which can not be distinguished from S. gaspensis or S. hercyni:e. 
MOLL USCOIDEA. 109 

1907. Spirijer perimele (pars). Clarke, New York State Mus. Bull. 107, p. 253, middle :figure (cet. excl., not the two 

side figures). 

Lower Devonic: Baker Point, Moosehead Lake, Somerset County, Maine. 

1907. Spirijer primmvus atlantica. Clarke, idem, p. 260, :figs. 

Lower Devonic: Baker Point, Moosehead Lake, Maine. 

1910. SJ>irijer gaspensis Billings. Williams, Roy. Soc. Canada Trans., 3d ser., vol. 3, pp. 211, 224. 

Spirijer arenosus fauna, St. Helens breccia: St. Helens Island, near Montreal, Canada. 

This Spirifer from the Moose River sandstone represents a for;m characteristic the world 

over of. rocks well up in the Eo-Devonian, following the S. murchisoni-primrevus or Oriskany 

(Taunusiau) regime. It is unknown as low as the Chapman sandstone. The species is of 

mediun1 to large size and is characterized by grea:t transv~rse extension of the shell, so that 

the width is typically more than twice and a.s much as three or more times the length;· cardinal 

extremities pointed, acute; lateral plications 10 or 11 to 13 or 14 (12 to 18 according to Billings) 

on the side. There is an elevated cardinal area, and the brachial valve is as deep as the pedicle 

valve, or deeper; fold highly elevated. 

The outl.ine is broadly triangular, with acute ·pennate extremities. Both valves are about · 

equally convex, with the brachial valve perhaps a trifle the more convex of the two. In the 

pedicle valve the umbo is arched and the beak incurved. On the interior the dental lamellre 

occupy the third furrow, or fourth ridge on each side of the median sinus. The musculature 

is strongly impressed, extends about. half the length of the shell, and is marked by a sharp 

elevated line which reaches perhaps half the length of the musculature. This line can not, 

however, be compared with the strong median septum characteristic of Delthyris. Billings, 

in his figure 8, shows the same line, impressed in the internal mold. In old shells the umbo 

is thickened on the outer side of the lamellre, and on internal molds pits (the impressions of 

ovarian pustules~) are unpressed in this calloused part· of the shell, as in S. murchisoni, S. 

primcevus, etc. The hinge line is long and straight and constitutes the maximum width of 

the shell. The proportions of length and width are indicated by the following figures: 

Dimensions of :Maine specimens of Spirijer gaspensis. 

[All from Littlo Brassua Lako (locality 1061 B').] 

Brachial valve ................................... . Do ......................................... . Pedicle valve .................................. . 

Length 

(millimeters). 

14 

17.5 

31 

ViTidth 

(millimeters).· 

32 

54 

92 

The cardinal area is of low to medium height. The delthyrium has not been clearly 

observed but appears to be very nearly if not quite 90°. . 

The brachial valve is also strongly convex, in some shells apparently more convex than 

the pedicle valve; the cardinal area is linear or absent; on the int~rior the median elevated line 

is strongly pronounced, assuming the character of a low septum; it extends nearly half the 

length and becomes thickened and prominent in its posterior portion, where the posterior 

adductor scars are sometimes discernible. 1 

In the Maine specimens, which are preserved in a dark bluish-black siliceous shale, the 

ribs are of moderate elevation, roun.ded, and with narrower inters paces; in the internal molds 

the ribs are commonly rounded and low (rarely angular and high), and the interspaces are 

ahnost if not quite as wide as the ribs. The sinus is of moderate depth, rounded or flattish in 

the bottom, very commonly marked on· the exterior by an obsolescent riblet, and is extended 

as a tonguelike projection in front. The fold in the brachial valve is strongly elevated and 

carinate, expanding in width rapidly toward the front. Fold and sinus are equal in width to 

three or four of the bounding ribs. The number of ribs in the :Maine specimens is 10 or 11 

lCf. Billings, Elkanah, op. cit., fig. SA. 
110 FAUNA OF THE CHAPMAN SANDSTONE OF MAINE. 

or more; commonly 13 or 14, in mature shells; some smaller specimens show more. The 

usual number at Gaspe, to· judge from Billings's ~gures~ is 13 or 14, though Billings states that 

the number of ribs on each side is from 12 to 18. In the small specimens from Maine, of which 

only four or five have been seen, the ribs are not m<:>re than 15 in number, though it is possible 

·that the larger specimens, which are only fragmentary, may have had more. At Nictau, Nova 

Scotia, the species has only 9 to 11 ribs on each side, generally about ,10. In the specimens 

from Nictau the outline is less extended transversely, and in this particular they present a 

close approach to Spififer murchisoni. 

The finer surface ornamentation of Spirifer gaspensis consi~ts of sublamellose closely set 

concentric lines. No indication of radial lineation was observed, but the specimens are too 

poorly preserved to show it, even if it should exist. 

Locality: Moose River sandstone, Little Brassua Lake, Somerset County, Maine. 

U.S. National Museum, catalogue No. 59747. 

Oomparisons.-Billings described his species as having a width "often twice the length; 

in some specimens shorter, one-fourth or only one-fifth greater than the length." Some of the 

Maine specimens are as mueh as three times as wide as long, and in none of the speeimens at 

hand is the width less than twice the length. There can be no doubt of the identity of the 

Maine forms with Billings's 'species, particularly as the exact proportion. of length and width 

is commonly variable in the Spirifers of this transversely elongate type. The ribs in the Gaspe 

specimens are slightly more angular than is common in those .from Maine·, but this character 

is more or less variable and is. also strongly influenced by the conditions of preservation. In 

one of the Maine specimens the ribs are angular, corresponding to Billings's description, but in 

other parts of the same specimen the ribs ar~ rounded. In all other respects and in the minuter 

details Billings's description might equally well have been drawn ~p from the Maine specimens 

at hand; and in none of the other characters do the Maine specimens depart from Billings's 

description or illustrations of S. gaspensis. 

Spififer gaspensis Billings and its allies may be distinguished from the Bpir~fer murchisoniprimrevus type by its more transversely elongated outline. The dental lamellre are farther 

removed from the median sinus, and the number of plications is greater. At Nictau, Nova 

Scotia, Spififer· gaspensis has a less transverse outline than is usual, and the specimens from 

this locality present a near approach to Spififer murchisoniJ· but they may be distinguished 

. by having 10 or 11 ribs on each side of the median fold and sinus, compared with a maximum 

of 8 or very rarely 9 inS. murchisoni. Moreover, the dentallamellre are at the third groove 

or fourth ridge on each side of the middle in the Nictau forms, but at the second groove or 

second ridge ill S. murchisoni. 

Transversely elongated Spirifers of the S. gaspensis type have not been reported from the 

New York and New Jersey Oriskany nor below the Onondaga. ·In the Oriskany of Maryland, 

however, occur two species very similar to S. gaspensis, namely, Spirijer cumberlandire Hall 

and Spififer submucronatus Hall. These forms differ from S. gaspensis in having a persistently 

lower, rounded fold and sinus, in having the musculature in the pedicle valve proportionately 

narrower and more elongate, and in never attaining the more extreme pennate form of Spirifer 

gaspensis as found in Maine. In the Maryland Spirifers the brachial valve is less convex than 

the pedicle valve. In New York the earliest Spirifer of the transversely elongated S. gaspensis 

type is Spirifer macrothyris Hall/ in which the width is more than twice the length, and the 

br.achial valve is distinctly and persistently more convex than the pedicle valve, with keeled 

fold, broad sinus, and strong musculature. Spififer macrothyris differs from S. gaspensis in 

having rectangular or rounded cardinal extremities, which give the shell a rectangular or 

transversely oval instead of pennately triangular aspect, as inS. gaspensis. The ribs are also 

coarser in Spififer macrothyris, and that species, though it attains a width of 100 millimeters 2 

or more, has only from 6 to 10 plications, never more than 10, whereas there are rarely less 

1 Hall, James, Paleontology of New York, vol. 4, p. 202, pl. 30, figs. 16, 20, 1867. See Schuchert, Charles, U.S. Geol. Survey Bull. 87, 1897_, for 

additional references. 

2 Weller, Stuart, Paleontology of New Jersey, vol. 3, pl. 52, figs. 1, 2, p. 375, 1903. 
MOLL USCOIDEA. 111 

than 10 in S. gaspensis. S. macrothyris has also an obtuse delthyrium. On the whole it is 

very closely allied to S. ·gaspensis and may prove to be a variant of that species. 

It is ilnportant to note that for these large shells of the S. gaspensis type the internal mold 

differs conspicuously fron1 the external shell in the number of visible plications, as well as in 

the outline of the '7 alves. The thickening of the shell in the old speci1nens extends to the 

hinge extremities, so that the large internal molds are frequently not so pennate and seem to show 

more rounded extremities than are found on the exterior. This feature has been strongly 

etnphasized by Drevermann,l who also points out that because of this internal thickening at 

the hinge extremities several plications which are found on the surface are not represented in 

the internal molds, so that such large internal molds seem to have fewer plications than are 

visible on much younger specimens. This condition is noteworthy in the Maine specimens, 

where a large pedicle valve over 90 millimeters wide has only 10 ribs on each side, with possibly 

one or two obsolescent additional ones, "rhereas another specimen only one-third that width 

has 13 or 14 ribs. As the published figures of S. macrothyris generally represent internal molds, 

the species as represented by external molds might be more pennate and might have more 

plica tions. 

In South America the transversely elongated Spirifers, as has already been indicated, are 

represented by Spirifer antarcticus of the Falkland Isla.nds. This speeies was described as trnnsversely fusiform, nearly equivalved, with a strongly elevated fold and deep sinus, strong musculature, and 10 to 12 ribs on each side. It has also a very high cardinal area and narrow delthyrium, features wP,ich seem to distinguish it from S. gaspensisJ· but too little is known of S. antarcticus ·to warrant definite separation or union with the Gaspe species, though it is certainly a 

very close ally and very probably identical. · 

In the Onondagan faunas of Brazil the gaspensis type is the dominant form of Spirifer. 

In the Rio Maecuru fauna this form has been called S. buarq_uianus Rathbun, as indicated below, 

but it is hn.rdly. distinct fron1 the specific type represented by Spi~{e1· gaspensis and S. hercynice. 

1879. Spirifera buarquiana. Rathbun, Boston Soc. Nat. Hist. Proc., vol. 20, p. 28. 

1903. Spirifer buarquianus var. contracta. . Katz~r, Geologie des unte1;en Amazonasgebietes, p. 272, p1. 10, fig. 1a. This 

form has the width less than 2i times the length; 9 to 12 ribs on each side. 

1903. Spirifer buarquianus vru·. alata. Katzer, idem, p. 272, pl. 10, figs. 1d, le. Width as much as four times the length; 

12 to 16 ribs on each side. 

S. buarq_uianus is·n1ore than twice (in some specimens as much as four times) as wide as 

long, the common proportion of width to length being 2.8 to 1. The outline is pennatel.y 

triangular, with acute hinge extremities; the brachial valve is equal to or exceeds the pedicle 

valve in convexity. The cardinal area is of moderate height with delthyrium less than 90°; 

mesial fold in the brachial valve strongly elevated and keele~, sinus fairly deep and equal in 

width to three ·or four ribs; ribs 9 to 16 on each side, commonly 12 to 14. Katzer's figure 1a 

represents a specimen practically ·indistinguishable from the one shown in Plate IV, .figure 7, 

of the present work, and hisS. buarquianus var. contracta can not be distinguished in appearance 

from S. gaspensis as it occurs in :Maine. Katzer mentions the occurrence of an obscure riblet 

in the sinus but states that no corresponding groove is ever observable on the fold except, 

rarely, near the beak. In this respect his form is like Spirifer gaspensis and also S. hercynice. 

Katzer described another transverse Spirifer from the Erere (Meso-Devonian) fauna of 

Brazil as Spir~fer peclroanus. This shell is very sin1ilar to S. gaspensis and was described by 

H.athbun 2 as having 10 to 16 ribs on each side, but Katzer states that the larger collections 

show the number to be nearer 20 and in some specimens as great as 23.- This number is 

greater than occurs inS. gaspensis, fron1 which the Brazilian species is also easily separated 

by its low cardinal area, which serves to associate S. pedroanus with the Middle Devonian 

Spi1·~[m· mucronat·us or pennatus in America and with the :Middle Devonian S. speciosus (pars 

auct.) in Europe. 

In the Lower Devonian of South Africa the specific ·type of S. gaspensis is represented by 

the specimen figured by Reed 3 and called Spirifer orbignyi Morris and Sharpe. The width is 

1 Palnoontogrnphicn, vol. 49, p. 9.'), 1902. 

2 Unthbun, Richard, Buffalo Soc. Nat. Sci. Bull., vol. 1, p. 237, pl. 8, figs. 1-9, 13, 14, 16-20, 1874. Spirijira pc'droana (Hartt MS.). 

u South Africo.n Mus . .Annals, vol. 4, pl. 22, fig. 4. 
112 FAUNA OF THE CHAPMAN' SANDSTONE OF MAINE. 

somewha.t mo.re than twice the length, and the musculature is strongly impressed and equal to 

half the length, with a very faint, low septum or line as inS. gaspensis .(also inS. hercynice. 

Giebel, S. macrothyris Hall, B. cumberlandice Hall, S. submucronatus Hall, and 0) S. antarcticus 

Morris and Sharpe). The dentallamellre occupy the third furrow or the fourth ridge on each' 

side of the median sinus; this is also their position in S. gaspensis Billings from Nictau (Nova 

Scotia), Gaspe (Quebec), and Maine;· S. macrothyris Hall, from New York and New Jersey; 

S. cumberlandice and S. mucronatus, from Maryland; S. antarcticus Morris and Sharpe, from 

South America; and S. hercynice Giebel, from Germany and France. The cardinal area is· of 

medium height, and there are. 11 or more ribs on each side of the fold and sinus. Reed's figure 4 

might almost exactly represent one of the Maine specimens, and his figure 5 apparently belongs 

to the same species. These South African specimens differ from S. hercynice and S. gaspensis, 

if at all, in having the sinus equal in width to two or three ribs instead of three or four or more, 

but it seems that they ought to be united under the same specific name with S. gaspensis. 

S. gaspensis is equivalent to and identical with S. hercynice Giebel. The masterly treatment 

of Giebel's species given by Scupin 1 firmly establishes this point. Had the Maine specimens 

been found in Germany, they would no doubt have been identified with S1Jirijer hercynice, 

even after the most detailed study. The only distinction that c·l}n be pointed out is that Scupin 

describes the musculature as equal to or more than one-third the length; it is frequently figured 

as half the length and in the variety primcev~formis Scupin 2 it is considerably more than half 

the length. Scupin states also that in S. hercyn ice there are 20 or more ribs on each side, whereas 

the highest number recorded by Billings for S. gaspensis is only 18; but a glance at the published 

figures of S. hercynice shows that the common number of plications is 13 or 14 on each·side and 

in old shells (internal molds) apparently only 11 (occasionally 10 or 12), exactly as inS. gaspensis~ 

In Spirifer hercynice the sinus is occasionally equal in width to as many as six ribs, but by far 

most commonly only to three or four, as in Spirifer gaspensis. In all observed respects Spirijer 

. gaspensis agrees with Spirijer hercynice; and as the two species have been c·arefully studied and 

no substantial distinctions can be pointed out, it seems necessary to recognize this European 

species as occurring in America. · 

This species is frequently confused 3 with Spi~fer paradoxus Schlotheim ( = Spirifer 

macropterus Goldfuss), an abundant species characterizing the ~igher Coblenzian horizons 

above the ''zone of Spirifer hercynice." . The later shell is distinguished from Spi~fer hercynice 

or S. gaspensis chiefly by its lower, ribbon-shaped cardinal area, in which it approaches the MesoDevonian types Spirifer speciosus Schlotheim, Spi~fer mucronatus Conrad, and Spirijer pedroanus Hartt and Rathbun. Spir~fer paradoxus is more profusely plicate than Spirifer gaspensis 

or S. hercynice, having a minimum of i6 to 20 ribs on each side, whereas this number is only 

occasionally attained as a maximum in the Lower Coblenzian form. 

Stratigraphic significance of the gaspensis type.-Spirijer gaspensis occurs in the Gaspe 

limestones Nos. 7 and 8, and in the lower part of the Gaspe sandstones, associated with such 

typical Oriskany species as Rensselaeria ovoides, Leptocmlia flabellites, Spirifer arenosus (or· 

superbus), Spirijer murchisoni, Eatonia peculiaris, Leptostrophias, etc.; consequently these 

beds have heretofore been considered of Oriskany age. The same fauna also characterizes the 

Moose River sandstone in Maine. However, transversely elongated shells with 10 or commonly 

more ribs on each side, represented by the gaspensis type of Spirifer, are unknown in the New 

York Oriskany; and in the New York section this type does not appear before the Schoharie 

grit. In Europe it is also absent in the Taunusian (Siegen graywacke) or zone of Spirijer 

primcevus (the supposed equiyalent of the Oriskany), and makes its first appearance in the ensuing 

zone of Spirijer hercynice, or Lower Coblenzian, which is below the Middle and Upper Coblenzian, the latter being correlated with our Onondaga limestone. This would indicate that beds 

containing elongated Spirifers of the type of Spirijer gaspensis ( = hercynice) are related to the 

European Lower Coblenzian and prob_ably later than the New York Oriskany. The san1e thing 

1 Scupin, Hans, Palaeontol. Abh. (Dames & Ko~en), new ser., vol. 4;pt. 3, p. 290, 1900. 

2 The variety primreviformis of Scupin strongly resembles the Oriskany shell from Illinois called S. engelmanni by Meek and Worthen in 1866 

( =Spirifer worthenana Schuchart). 

~See Beclard, Ferd., Les spiriferes du Coblenzien beige: Soc. belge geologie Bull., vol. 9, pp. 199-218, p. 272, pl. 14, 1895; Catalogue synonymique et critique des spiriferes du Devonian inferieur: Idem, pp. 260-288. 
MOLL USCOIDEA. 113 

is further indicated by the occurrence at Gaspe of such Onondaga ("Corniferous") types as 

Chonetes antiopa, Chonetes laticosta Hall, Chonetes (Eodevonaria) melonicus Billings (and, in 

the :Moose River sandstone, of 0. (E.) arcuatus and Spiriferduodenarius), Orthis (Rhipidomella) 

livia, LeptostroJJhia blainvillei (cf. L. perplana, "Corniferous" form), Delthyris raricosta, etc., 

and the great abundance of Fucoides (Spirophyton) caudagalli, the characteristic fossil of the 

otherwise barren Esopus (" Caudagalli ") grit overlying the Oriskany in New York. 

In the Oriskany of the region from southern Pennsylvania to Virginia, which yields the. 

nortnal Oriskany faun~ augmented by Spirifer cumberlandif£ Hall and Spirijer submucronatus 

Ilall, the two species natned represent the gaspensis type of Spirifer. It was therefore inferred 

that this Oriskanian region, like that in Acadia, represented the Lower Coblenzian or "zone of 

SJJi?'ife?' hercynif£" of Europe, a zone which is a trifle younger than the Oriskany of New York. 

This inference, which was supported by the occurrence in the Pennsylvania-Virginia region. 

of the European Spirije1· daleidensis Steininger and by Schuchert's recent discovery of TropidoleJJt'l.tS carinatus (Com·ad)-a n1ost characteristic Lower Coblenzian guide fossil in Europe, 

South Mrica, and South America-is confirmed by E. 0. Ulrich, who states that within the 

Oriskany of the Pennsylva.nia-Virginia region is recognizable a distinct interval anted~ting 

the occurrence of the cumberlandif£-submucronatus-gaspensis type of Spirifer. 

In Illinois, in the beds which have yielded the Spirijer engelmanni and the Spirifer hemicyclus of Meek and Worthen with the so-called Oriskany fauna in Union County, as well as in 

the lowest beds (the beds preceding these containing the Onondagan or "Corniferous" fauna) 

in the section at the Devils Backbone and Devils Bake Oven,t in Jackson County, the Lower 

Co blenzian or "zone of S pi?vife?· hercynif£" also seems to be present. 

In South America the Falkland Islands Eo-Devonian with Spirijer antarcticus, Leptocmlia 

jla,bellites, OhonostroJJhia 0) tenuis, etc., seems to represent this same horizon, and there is some 

ground for believing that the Devonian of South Mrica, the Rio Maecuru fauna of Para, Brazil, 

and the Eo-Devonian litnestones of the Eureka district, Nev., likewise represent substantially 

the sa1ne zone. 

It is therefore of great interest. to note that not only has Spirifer hercyni::e been found in 

America, but, as in Europe, :it is. the dominant type of Spirifer of a narrowly limited series of 

fossiliferous beds that are widely distributed in North and South America (probably in South 

Africa also) and that hold the same stratigraphic position as the Lower Coblenzian in Europe. 

This position in the column represep.ts some part of the interval between the Oriskany and 

"Corniferous," an interval which, in the New York section, is occupied by the barren Esopus 

grit and the nearly barren Schoharie grit. A new fossiliferous zone is thus added to the New 

York Lower Devonian. An ~extended discussion of this point would be out of place in the 

present paper. The preceding relatively brief notes have been framed because of the interesting 

fact th~t the zone of Spirijer hercynif£ or Unter Coblenzian of European authors has never before 

been recognized as such in America, and the occurrence here noted is the first one reported outside 

of Germany, France, and Belgiun1. 2 Tllis Lower Coblenzian zone of Spi?'ifer hercyni::e comprises 

the so-called "Oriskany" of Quebec, Maine, Nova Scotia, and New Brunswick, and is well 

developed in Son1erset County, :Maine. The typical or theoretically older New York Oriskany 

is apparently absent. The Chapman sandstone represents a still lower horizor1 than either. 

SPrRU...,ER 1\:IONTREALENSIS Williams,., 

Plate I, figure 2; Plate II, figures 2, 18. 

1901. Spirifer cf. S. granulosus Comad. Schuchert, Am. Geologist, vol. 27, p. 252. 

Limestone with S]Jirijer macnts: St. Helens Island, Montreal, Canada. 

1910. S7Ji'l'ije1· monttealensis. Williams, Roy. Soc. Canada Trans., 3d ser., vol. 3, p. 222, pls. 1, 2. 

I..imestone breccia: St. Helens Island, Montreal, Canada. 

1 Woller, Stuurt, Corrolution of the Devonian fatmas in southern Illinois: Jour. Geology, vol. 5, pp. 625-633, 189i. 2 Since the above paragraph was written J. M:. Clarke has published a paper entitled" Evidences of a Coblenzian invasion in the Devonic of eastern North America" (Memorial volume to Prof. Adolf von Koenen, pp. 359-368, Stuttgart, 190i). In this paper Clarke emphasizes the Lower 

Cobleuzio.naspect of tho l\foose Hiver sandstone. · 

50245°--~0.89--16----8 
114 FAUNA OF THE CHAPMAN SANDSTONE OF. MAINE • . ' 

Although this species does not appear in the fauna of the Chapman sandstone, it is here· 

described and illustrated in order that the reader may compare it with S. concinnus, which belongs 

to the Chapman fauna, and with S. granulosus, which is' of much later date. In the upper 

breccia of St. Hel~ms Island S. riwntrealensis is found associated with S. arenosus, but S,. concinnus is absent. The latter species, however, is present in the lower fauna of St. Helens Island. 

In the Gaspe series B. concinnus is lacking, although S. arenosus appears as low as the Grande 

Greve limestone. In the New York section S. concinnus appears to be restricted to. the faunas 

underlying the zone of S. arenosus. The problem of correlation thus involves considerable 

difficulty. · . 

The first reference to the species was made by Schuchert; later it was fully discussed by 

Williams, as indicated by the references cited above in the synonymy. The specimens referred 

. to by ·Schuchert ·came from a large block of slightly. granular siliceous limestone, dark gray 

when fresh, weathering a rusty yellow, associated with an agglomerate. These specimens, 

which present an unmistakable Hamilton aspect, led Whiteaves 1 to state that the St. Helens 

Island fossils "are probably the-equivalent of part of the Hamilton formation of Ontario and 

New York, and not of the Lower Helderberg." That Helderberg fossils of about the age of 

the Becraft limestone occur on St. Helens Island was shown by Schuchert/ and a Becraft Spirifer 

from these rocks, S. concinnus, is figured in the present work. The limestones, however, which 

contain the species S. concinnus were· .shown by Williams in 1910 to belong to a fauna quite 

distinct from the block in the breccia containing S. arenosus and S. montrealensis. · ' 

The present species is a large Spirifer with the brachial valve gibbous, as deep as the pedicle 

valve, or deeper. The pedicle valve has a high, slightly arched cardinal are.a, with a delthyrium 

of about 60°, or as wide as it is high; the surface is· covered with about 18low, rounded, narrow 

ribs, with much narrower interspaces, on each side of the simple fold and sinus; the latter equal 

in width five to seven ribs. The sinus is angular; the fold is rather strongly elevated but not 

keeled and is evenly rounded except for a slight median groove on the surface, confined to the 

posterior part and hardly if at all impressed on the ~nternal molds. The ratio of length to 

width is 10 to 17. Schuchert mentions strong dental plates, but his specimens were internal 

molds, and the specimens figured here are external casts on _which the dentallamellffi are not 

represented. 

Locality: Upper beds of the limestone breccia (probably Meso-Devonian), St. Helens 

Island, Montreal, Canada. 

Comparisons.-The Montreal shell resembles Spirij'er oweni Hall, which is usually regarded 

as the Mis·sissippi Valley equivalent of S. granulosus, but it lacks the grooving of the ribs 

commonly' developed inS. oweni Hall. As compared with the New York forms of S. granulosus, 

S. montrealensis has slightly narrower ribs and lacks the median rib let in the sinus; in adult 

specimens, moreover, the median groove on the fold is confined to the posterior (young) part 

of' the shell. In small specimens this groove is evident for at least half an inch from the beak 

for"ward. In S. oweni and typical S. granulo,sus it is often strongly developed on maturer 

specimens all' the way to the front margin .. 

Genus ANTISPmiFER. gen. nov. 

Among the fossils from the Somerset County localities of the Moose River sandstone have 

been found a considerable n~mber of specimens of a small Spirifer resernbljng crushed specimens of a small Spirifer murchisoni .. Critical examination shows that they are not crushed but 

exhibit what may be called a resupinate growth of the shell, such as makes the Orthothetes fonn 

of strophomenoids or the Chonostrophia form·of Chonetes. · The name Antispirifer is proposed 

to designate this peculiar genus, the character of which is indicated by the following diagnosis: 

Small shells havjng the brachial valve convex, as is normal in Spirifer, but with the pedicle 

valve flat, depressed convex, or slightly concave, sometimes becoming subgeniculate or convex 

in front in the older shells. Outline, as in Spirifer, semicircular or triangular wi~.h a long, straight 

1 The Devonian system in Canada: Am. Assoc. Adv. Sci., Sec. E, Presidential address, 1896, p. 16. 

2 Am. Geologist, vol. 27, p. 252, 1901. 
MOLLUSCOIDEA. 115 

hinge line equal to the greatest width of the shell. Cardinal area distinct, triangular, equal in 

width to the width of the valve, and of inediun1 height. The cardinal area is either plane or 

slightly m:ched; when arched the direction of the arching is convex, the reverse of that common 

in Brachiopoda. DQ.lthyrium triangular; probably closed, as in Spirifer, by a deltidium. In 

the internal and external n1olds of isolated valves, the. condition in which· the fossils are presen'ed, it is not apparent whether the delthyrium was closed or open. On the interior of the 

pedicle valve dentallamellre are developed as in normal Spirifers, and in older individuals there 

is a thickening deposition of shelly matter on the interior at the outer side of the lamellre. The 

musculattu·e is then strongly impressed and triangular in outline, recalling in character that of 

Spirifer murchisoni and S. gaspensis. There is sometimes discernible a faint elevated line in 

internal 1nolds, or an incipient 1nedian septu111 extending down the middle of the musculature, 

s01newhat as inS. gaspensis; but there is no real median septum in the pedicle valve, such as 

occtu·s in Delthyris, Cyrtina, Spiriferina, etc. In the brachial valve the cardinal process is simple 

and radiately striate; the crural bases diverge strongly, producing an elevated front margin for the 

rather deep dental sockets, which are smooth-that is, uncrenulate. The hinge plate is thus the 

san1e as in Spirifer, as is also the musculattu·e. T.he narrow elevated line or incipient "median 

soptmn" of the brachial valve of Spirifer is obscurely developed. Brachial structures unknown. 

The surface ornamentation consists of radial plications with sinus in the pedicle' valve and 

fold in the brachial valve, as in Spirifer. The type ai1d only species. of Antispirifer has strong 

concentric close-set lamellre crossed by fine radial lines as in Spirifer murchisoni. Shell structure 

finely fibrous, impunctate under a hand magnifying glass. The fossils as preserved present a 

close resen1blance to the well-known Vitulina pustuloscL. The shells are of about the same size 

and outline and have also the same convexity and number of ribs. The more convex valve has a 

median fold, and the flat valve has a narrow, simple, abrupt median sinus; but in Vitulina the 

flat valve is the brachial valve, whereas in Antispirifer' the flat valve is the pedicle valve and 

may be easily recognized by· its strong triangular musculature and cardinal area. In Vitulina 

the shell structure is p:unc~ate; in Antispirifer it is impunctate, under a hand magnifying glass. 

In Vitulina pustulosa there is a median groove in the fold, and the base of the median sinus is 

convex, so that there appears to be a strong plication filling the bottom of the sinus. In Antispirijer harroldi the fold is si1nple, and the bottom of the sinus is flat or concave, with (rarely) a 

faint narrow obsolescent riblet in the base. The musculature on the interior is very distinct in 

Vitulina and Antispirifer; unfortunately no comparison can be made of the brachial structures, 

for these are imperfectly known in Vitulina and not at all known in Antispirifer. Antispirifer also 

presents some analogies with Leptocrelia, "Crelospira," etc., but in these plica ted plano-convex 

shells, as in Vitulina, the brachial valve is flat and the pedi.cle valve more strongly convex, 

whereas tho reverse is true of Antispirifer. They are also sri1aller, have no cardinal area, and 

show a curved hinge line. · · 

One of the closest allies of Antispirifer is Anabaia Clarke. 1 This spiriferid genus shares the · 

peculiar feature of Antispirifer in having n. fln.t pedicle valve and a convex brachial valve, but it 

is affiliated with "Crelospirii.," Leptocrelia, etc., in the absence of any cardinal area, in the 

rounded hinge line, and in the character of the musculature, septa, and cardinal process, which 

arc sin1ilar to those of Leptocmlia flabellites. 

Antispirifer shows the closest affiliation with Spirifer in the wide, straight hinge line, welldeveloped cardinal area, and triangular delthyrium; in the musculature, dental lamellre, and 

absence of real septa; in the simple, rn.dially striate cardinal process; and finally in the general 

outline, ribbed surface, and finer surface markings. The only distinction which can be pointed 

out between Spirifer and Antispirifer is that in the latter the pedicle valve is less convex than the 

brachial valve. It is well known that in the g~nus Spirifer the pedicle valve is always strongly 

convex-with very rare exceptions, more convex than the brachial valve. In these rare exceptions, which include Spirifer macrothyris Hall, S. ac'l.tminatus (Conrad), S. granulosus (Conrad), 

. S. cultrijugatus Roemer, S. gaspensis Billings ( =S. hercynice Giebel), and sometimes S. murchisoni 

1 Clarlco, J. M., Uppor Silurian fmum of tho Rio 'rrombotas, Province of Para, Brazil: Mus. Nac. Hio de Janeiro Arch., vol. 10, 1899 (author's 

English od., p. 12, Albany, HlOO). Soo also Hall, James, and Clarke, J. M., Paleontology of New York, vol. 8, pt. 2, p. 141, figs., 1893. 
116 FAUNA OF THE CHAPMAN SANDSTONE OF MAINE. 

Castelnau, the greater convexity of the brachial valve is effected by the development of a 

high keeled fold. These large Spirifers can not be mistaken for Antispirifer, for they have a 

strongly convex pedicle valve, where:;ts in Antispirifer the pedicle valve is flat. Moreover, in 

the brachial valve of Antispirifer the fold is not keeled but is, on the contrary, rather low and 

broadly rounded. Antispirifer, as has· been indicated, is rP;presented by much smaller shells. 

ANTISPIRIFER HARROLD! sp. and gen. nov. 

Plate V, figures l--13. 

Small Spirifer-like shell with flattened or resupinate pedicle valve; width slightly greater 

than the length; four to six ribs on each side of the simple fold and sinus. Pedicle valve flat or 

very depressed convex, rarely slightly concave; beak elevated above the hinge line, tip slightly 

incurved., and surface sloping in a plane to the sides and front; very slightly curved near the 

anterior margin. Outline somew:hat pentagonal; posterior margin diverging in two nearly 

straight lines at an angle of about 145° to 155° from the beak to the hinge extremities, which 

are rectangular and somewhat pointed or slightly rounded. The lateral margins are subparallel, 

conv;erging from the cardinal extremity nearly opposite the midlength, where they curve into 

the front margins, describing nearly a semicircle. The greatest width, which is between the 

cardinal extremities, exceeds the length ·25 to 30 per cent. The cardinal area is well developed, 

of medium height, plane, or rather commonly very slightly arched, with the conv·ex side of the 

arch directed posteriorly-contrary to the normal arching of the area in the Brachiopoda-and 

forming an angle of 140° to 160° with the plane of the margin. The delthyriun1 is large, triangular, acute, 60° to almost 90°, but it is impossible to state definitely whether it was closed or 

open. In the great majority of Spirifers as ordinarily preserved the deltidium has become 

detached, so that the delthyrium appears to be open. When such shells are preserved as internal 

molds the interior filling of the valve is continuous with the external matrix through the delthyrium, which would not· be the case if the deltidial covering intervened. These n1olds therefore seem to i~dicate an open delthyrium, as do the few clean pedicle valve molds of Antispi'rifer 

harroldi which have been observed. However, as· the true Spirifers that are known to have had a 

closed delthyrium are commonly preserved in the same way, and as Antispirifer so closely resembles Spirifer in most of its essential features, its delthyrium was probably closed as in Spirifer. 

On the interior of the pedicle valve there is a strongly impressed musculature, which is triangular 

to lozenge-shaped or pentagonal in outline, much like that of Spirifer murchisoni. It extends 

one-half to three-fifths the length of the shell and is longer than wide, the ratio of length to width 

varying from 1! :1 .to 2:1, commonly nearer the former figures. It is limited on the sides by 

well-developed dentallamellre, standing under the third ridge on each side of the median sinus 

and extending one-fifth the length of the valve· or less. The dentallamellre are strong in young 

shells, where they leave in the internal mold a clean incision; but toward n1aturity the cavity 

on the interior of the valve outside of the dentallamellre becomes filled in by the deposition 

of shell substance, and the internal molds of such mature forms present the highly elevated 

tonguelike cast of the musculature so characteristic of Spirifer murchisoni, Spirijer gaspensis, etc. An incipient median septum, or rather low elevated line, is developed between 

the muscular scars toward maturity (as in Spirifer hercynire and S. gaspensis), beginning 

at the posterior edge and extending only part way down the musculature. It is absent 

in most specimens, and when at all recognizable leaves a barely discernible impressed 

line in the internal mold, thickening at the posterior tip of the musculature. Such a line 

is present in many if not in most Spirifers and should not be confounded with the strong, 

sharp median septum of Delthyris. The brachial valve is decidedly convex, the greatest 

height in the middle being from three-tenths to one-third the length .. It presents the aspect 

of a convex brachial valve of Oyrtina hamiltonensis, 0. heteroclita, or 0. dalmani, and may 

indeed be readily mistaken for Cyrtina 'in detached specimens. The outline is trapezoidal 

or semicircular, with a wide, straight hinge line equal to the width of the valve; the beak 

extends slightly over the hinge border. The lateral margins are subparallel from the rectangular hinge extremities, at first converging only slightly and then curving into the front 
MOLL USCOIDEA. 117 

margin, forming a semicirele. The width is from 30 to 50 per cent greater than the length, commonly nearer the former figure. A narrow cardinal area is discernible in s01ne speci1nens. On 

the interior of the brachial valve the cardinal process is simple and radially striated, as in Spirifer, 

and seetns to be merely the coalesced extremities of the crural bases. The crural bases diverge 

at a wide angle, are ahnost parallel to the hinge line, and produce an elevated front border for the 

diverging dental sockets. The brachial structures are unknown. The adductor scars are feebly 

if at all impressed. A trace of the elevated mediap.line present in Spirifer, Cyrtina, etc., is sometimes discernible, thickening slightly toward the beak. 

On each side of the siruple fold and sinus the surface is elevated into five or SL"\: radial plications, the outermost one rather obsolescent; rarely only four are discernible. The plications 

are rounded,.moderately to strongly elevated (only moderately elevated or rather low in the 

brachial valve), and with narrower interspaces. The ribs are preserved on the internal molds, 

where they are sometimes subangular, and, as is normal in plicated shells, the interspaces are 

wider than on the surface. The sinus in the pedicle valve is abruptly sllll:ken below the plane 

of the surface and is flat at the bottom. The fold is of low or moderate height and rounded. 

Fold and sinus are simple. The sinus is slightly wider or slightly narrower than the bounding 

rib. The width of the fold is nearly equal to the width of two bounding ribs. The finer surface 

markings consist of close-set, concentric, elevated imbricating lamellre, of which eight or nine 

may be counted in the length of 5 millimeters near the front of the shell. These are crossed by 

fine radiating lines, of which there are four to SL"\: in the width of a millimeter, and which become 

spinulose on the crests of the lamellre. The ornamentation, both coarse and fine, seems to be 

more conspicuous on the pedicle valve than on the brachial valve. 

The measurements of a few pedicle valves show the following din1ensions of length and 

width, re$pectively: 12 by 16 millimeters; 11 by 15 millimeters; 12.5 by 17 millimeters; 12 by 

15 1nillimeters; 15 by 17 + millimeters. 

Three brachial valves measure: 11 by 14.5 1nillimeters; 12.3 by 17 millimeters; 8.3 by 13 

millimeters. . 

The shell structure is finely fibrous and impunctate under a hand lens. 

The gregarious habit of the species is indicated by its abundance wherever it occurs. The 

only .fossil with which Antispirifer harroldi is likely to be confused is S~rifer murchisoni, which 

it resembles in the strong musculature, number of plications, and fine surface markings. From 

this fonn Antispirifer may be distinguished by its smaller size, less transverse outline (especially 

conspicuous in ,the brachial valve), flat pedicle valve, and plane or inversely arched cardinal 

area. The concentric ornamentation is stronger and the dental lamellre are farther from the 

middle, being at or beyond the third ridge from the median sinus; they are at the· second ridge 

or second furrow inS. m'l.trchisoni. As has been stated, isolated brachial valves of Antispirifer 

hm·rouli may be easily 1nistaken for the brachial valves of such Cyrtinas as 0. hamiltonensis I-Iall, 

0. dalmani 1-Iall, or 0. heteroclitct De France. 

Localities: Moose River sandstone (locality 1100 A or A'), abundant; associated with 

Leptocmlict flabellites, Spirifer murchisoni,· Moosehead Lake (locality 1076 E 3), associated with 

Leptocmlia flabellites;" Parlin Pond (locality 1059-12), associated with Leptocmlia flabellites. All 

these localities are in Somerset County, Maine. 

U.S. Nationall\1useum, catalogue Nos. 59748, 59749, 59750. 

ANTISPIRIFER HARROLD! var. TRANSVERSA n. Val'. 

Plate IV, figures 8, 9. I 

A few Antispirifers in the :Maine collections are distinguished from the normal forms by 

a n1ore transverse outline. The length and width of some of these transverse speci1nens, in 

millitneters, nrc: Pedicle valves, 12 by 25, 10 by 18; brachial valves, 11 by 22, 12 by 22. 

No U1ter1nediate forms occur. These specimens might be regarded as aberraJlt forms of 

Spi1vjfm· 'murchisoni, for they hnve the dental lamellre on the second ridge as in that species, 

but they have the flat pedicle valve and plane or inversely arched cardinal area of Antispirifer. 

The fossils 1nny represent a distinct species instead of variety. 
118 FAUNA OF THE CHAPMAN SANDSTONE OF MAINE. 

Localities: Moose River sandstone, Detroit (locality 1100 A'), rare; Parlin Porid (locality 

1059-12, common; locality 1059, rare; and locality 1059 C, abundant and large). All in 

Somerset County, Maine. 

U.S. National Museum, catalogue Nos. 59751, 59752, 59753. 

Family ATHYRIDJE Phillips. 

Genus NUCLEOSPmA Hall, 1859. 

N ucLEOSPIRA VENTRICOSA Hall. 

Plate V, figures 31-33. 

1857. Spirifer ventricosa. Hall, New York State Cab. Nat. Hist. Tenth Ann. Rept., p. 57. 

Lower Helderberg limestone: Albany County, N. Y. 

1859. Nucleospira ventricosa. Hall, Paleontology of New York, vol. 3, p. 220, pl. 14, fig. 1; pl. 28 (B), figs. 2-9. 

Sbaly limestone of the Lower Helderberg group:.Helderberg Mountains, Schoharie, and Cherry Valley, N.Y.; 

Cumberland, Md., etc. . 

1859. Nucleospira ventricosa. Hall, New York State Cab. Nat .. Hist. Twelfth Ann. Rept., p. 25, figs. 

Lower Helderberg: New York. 

1867. Nucleospira ventricosa. Hall, Paleontolog-f of New York, vol. 4, pp. 277, 278. 

Lower Helderberg: New York. 

1886. Nucleospira ventricosa. Darton, Am. Jour. Sci., 3d ser., vol. 31, pp. 212, 214. 

Lower Helderberg: Cornwi\11 station, Orange County, N. Y. 

1893-95. Nucleospira ventrico.s.a. Hnll and Clarke, Paleontology of New York, vol. 8, pt. 2, p. 145, figs. 128-130; pl. 48, 

figs. 2-6, 18; pl. 84, figs. 3Q-40. 

Lower Helderberg: Helderberg Mountains and Schoharie, N. Y. 

1897. Nucleospira ventricosa. Schuchert, U. S. Geol. Survey Bull. 87, p. 273. 

Lower Helderberg: Schoharie, Cherry Valley, etc., N. Y.; Cumberland, Md. 

1897. Nucleospira ventricosa. Weller, Jour. Geology, vol. 5, No.6, p. 627. 

Lower part of Upper Helderberg:1 Devils Bake Oven, near Grand Tower, Jackson County, Ill. (Zone I). 

1899. Nucleospira ventricosa. Prosser, New York State Geologist Seventeenth Ann. Rept. (for 1897), p. 340. 

New Scotland shaly limestone: Countryman Hill, Albany County, N. Y. 

1901. Nucleospira ventricosa. Prosser, New York State Geologist Eighteenth Ann. Rept. (for 1898), p. 55. 

New S.cotland shaly limestone: Indian Ladder section, Countryman Hill, Albany County, N. Y. 

?1903. Nucleospira cf. N. ventricosa. Schuchert, U. S. Nat~ Mus. Proc., vol. 26, p. 417. 

Manlius shaly limestone: Cash Valley, near Cumberland, Md. · 

1903. Nucleospira ventricosa. Weller, Paleontology of New Jersey, vol. 3, pp. 83, 87, 290, 316, pl. 30, figs. 19-22; pl. 37, 

fig. 16. 

Upper Coeymans limestone: 1! miles northeast of Hainesville, N. J. 

Upper New Scotland shaly limestone: Nearpass section, N.J. 

1903 . . Nucleospira ventricosa, Van Ingen and Clark, New York State Mus. Bull. 69, pp. 1189, 1193, 1203, 1207. 

Upper Coeymans ~nd upper Becraft limestones: Near Rondout, N.Y. 

Oriskany siliceous limestones: Glenerie, N. Y. 

1905. Nucleospira cf. N. ventricosa. Clarke, New York State Mus. Bull. 80, p. 146. 

Grande Greve limestones: North shore of Gaspe Bay, Queb~c. 

1905. Nucleospira ventricosa. Shimer, idem, pp. 207, 219, 220, 255, 264. 

Coeymans limestone and(?) upper New Scotland: Trilobite Mountain, Orange County, N.Y. 

?1905. Nucleospira cf. N. ventricosa. Hartnagel, idem, p. 355. 

Rosendale cement bed: High Falls, N.Y. 

1905. Nucleospira sp. Williams and Kindle, U. S. Geol. Survey Bull. 244, pp. 28, 32, 48. 

Top of Hancock limestone: East fork of Powell River (above flouring mill; station 1376A), Big Stone Gap, 

Wise County, Va. · 

Giles sandstone [in beds of Oriskany age]: 1-! miles above Hicksville (station 1379A'), Bland County, Va. 

An internal mold ·with both valves in conjunction and an isolated pedicle valve have 

been found in the Chapman sandstones at locality 1099 C', on Edmunds Hill. Another isolated 

pedicle valve comes from a point 2t miles west of Presque Isle Stream. The specimens are too 

poorly preserved for a detailed specific description, but· the outline, convexity,· and cu:r:vature 

are those of N. ventricosa.; there is a ,narrow median sinus or groove on the pedicle valve, and 

in the interior a low linear median septum and two thick unsupported teeth. A circular or 

'Probably representing the horizon of the Moose River sandstone of Maine. or zone of" Spirifer hercynire." 
MOLL USCOIDEA. 119 

oval 1nuscular scar is . divided longitudinally by the median septum a.nd exte:nds fron1 the 

1niddle of the shell a trifle 1nore than half the dista:n.ce to the bea.k; this seems to be the sca.r of 

the adductors, while the diductor muscles appa.rently do not leave any discernible impression. 

In the brachial valve there is 'H.lso a linear median septum extending nearly to the front margi11, 

slightly stronger than that of the pedicle valve and ending in a massive bilobed cardinal process. 

The peculiar distinctness of the oval adductor scar, especially as compared with the diductor 

scar, the occurre:nce of a median linear septun1 i:n both valves, and a massive cardinal process, 

which is re1narkably ponderous for such small shells, serve to recall the inter,nal structures of 

Leptocmlia flabellites. ' 

Locality: Chapn1an sa)ldstone, Edmunds :ijill, and 2! miles west of Presque Isle Stream, 

Chapn}an 'rownship, Aroostook Cou.nty! Maine. 

U.S. National Museum, catalogue Nos. 59754, 59755. 

Genus LEPTOC<ELIA Hall. 

The :first definition and illustration of the genus Leptocrelia was published by I!all 1 in 1859. 

The date (1859) fo~· the original and valid publication of the nan1e Leptocrelia is determined by 

the' rules of zoologic nmnenclature adopted by the British Association in 1842,2 according to 

which "two things are necessary before a zoological term can acquire authority, viz, definition 

~nd publication." 

In 1857 the nude generic name Leptocrelia 3 had been applied to three new species, L. concava, L. imb1'icata, and L. propna, but no definition of the name was given. 

In connection with the publication of the definition in 1859 three· species were named, 

described, and figm·ed. The fu·st species was Leptocmlia flabellites (Conrad), which must, thereforo, sorYo as the genotype. 

In the original definition of the genus a supposed brachial loop sinlilar to the loop of terebratuloid braclliopods was interpreted fro·m some mineral fillings described and figured in a 

single cast of LeJJtocmlia flabellites. · No confu·mation of the interpretation of these appendages 

h11s oYer been 1nade. For several years Leptocrelia was supposed to belong with the Terebratulas, but .in 1863 spiral appendages were discovered· in the species Leptocmlia concava Hall,4 

and tllis feature is sufficient to remove that species fron1 the terebratuloid type. The discovery 

of the spiral appendages in itself, however, did not justify the founding of the genus Crelospira, 

to which L. concava was referred. 

Studies by Hall and others have cast much doubt on the correctness of the interpretation 

of the "bracllialloop" in L .. flabellites. Paleontologists to-day regard the loop as nonexistent 

in Leptocrelia, which is regarded as spire-bearing. 5 Leptocmlia .fiabellites is similar in internal 

features to Nucleospira vent1·icosa, as has been indicated in the description of the latter form. 

Tho uncertainty regarding the brachial appendages. of Leptocrelia does not, however, 

in,Talidate the original definition of the genus. So long as there is no certain knowledge regarding the appendages of Leptocmlia .flabellites, the genus Leptocrelia may be assumed to be different frmn Crelospira. EYen if Leptocmlia .flabellites were found to possess spiral appendages 

like those of Crelospira, the result would not disturb the validity of Leptocrelia; it would merely 

serYe to prove that Crelospira is congeneric with Leptocrelia, from wllich it was removed chiefly 

on account of the presence of spiral appendages. In any event the name Leptocrelia is applicable 

to At?'YJJa .flabellites Conrad. 

Reference of Leptocrelia to Aiwplotheca Sandberg'er, as proposed by Schuchert, 6 on the 

ground of certain si1nilarities, semns untenable. In the definition of Anoplotheca Sandberger 

e1nphasizos the absence of pedicle opening, hinge area, and · deltidium, 7 as follows: ''Testa 

ovata, convexo-concava, in1perforata, area et deltidio carens," and, in Ge.I_'man, "Schale von 

1 Paleontology of New York, vol. 3, p. 447, pls. 103B and 106. 

9 See Am. Jour. Sci., 2d ser., vol. 48, p. 102, 1869. 

a New York State Cab. Nat. Hist. Tenth Ann. Rept., pp. IOi-108, 1857. 

t Now York State Mus. Sixteenth Ann. Rept., p. 60, 1863. 

6 New York State Geologist Thirteenth Ann. Rept., p. 803, 1894. 

o U.S. Qeol. Survey Bull. 37, p. 144,1897. · 

7 K. Akad. Wiss. Wien, Sitzungsber., Math.-naturw. Kl., vol. 16, p. 6, April, 1855. 
120 FAUNA OF THE CHAPMAN SANDSTONE OF MAINE. 

eiformigem Umrisse, convex-concav, ohne Sti_eloffnung, Schlossfeld, und Deltidium." In the 

specific description of Leptocmlia flabellites the beak is described as having ''a small round 

perforation in the extremity which is completed on the lower side by the deltidial pieces." 1 

In the description of Leptocmlia jimbriata the same pedicle opening and deltidial pieces are . 

noted. 2 These differences in structure, so positively indicated in the original definition of the 

genera, and present doubt regarding the similarity of the brachial appendages of Leptocmlia 

and of Anoplotheca are sufficient grounds for not confusing the genera. Leptocmlia will therefore continue to stand as the proper generic name for Leptocmlia flabellites (Conrad), Leptocmlia 

fimbriata Hall, and their congeners. · 

LEPTOC<ELIA FLABELLITES (Conrad). 

Plate,V, figures 19-30. 

1837. "Terebratulre." Jackson, First annual report on the geology of the State of Maine, p. 128, pl. 50, fig. 6, (pars), 9. 

Graywacke: Maine. · · 

1839. cf. Orthis callactis (not Sowerby). Murchison, Silurian system, p. 701. 

Brownish sandstone: Cedar Mountain, north of the Cape Colony. 

1840. Orthis callactis (not Sowerby). De Verneuil, Soc. geol. France Bull., vol. 11, p. 166. 

Sandstones: Cedar Mountains, Cape Colony. 

1841. Atrypajlabellites. Conrad, New York Geol. Survey Fifth Ann. Rept., p. 55. 

Oriskany sandstone: Near Saugerties, N.Y. . 

1842. Terebratula peruviana.3 D'Orbigny-, Voyage dans I' Amerique meridionale,.vol. 3, pt. 4, p. 56; .Atlas, pl. 2, figs. 

22-25. 

Sandstone: Rio Chalhuani, Bolivia. 

1846. Atrypa palmata. Morris and Sharpe, Geol. Soc. London Quart. Jour., vol. 2, p. 276, pl. 10, fig. 3. 

Devonian: Falkland Islands. 

1856. Orthis palmata. Sharpe and Salter, Geol. Soc. London Trans., 2d ser., vol. 7, p. 207, pl. 26, figs. 7-10. 

Ferruginous rock: Cold Bokkeveld, South Africa. 

Dark schists: Warm Bokkeveld, South Africa. 

"With Conularia in the Cedarberg" (Cedar Mountains), South Africa. 

Light-colored schists: Kolanans Kloof, South Africa. 

1857. Leptocrelia propria. Hall, New York State Cab. Nat. Hist. Tenth Ann. Rept., p. 108. 

Oriskany sandstone: New York, Maryland, Canada. 

1859. Leptocreliajlabellites. Hall, New York State Cab. Nat. Hist. Twelfth Ann. Rept., p. 33, figs. 1, 2, 4. 

No formation or locality given. 

1859. Leptocreliajlabellites. Hall, Paleontology of New York, vol. 3, p. 449, pl. 103B, fig. 1, pl. 106, fig. 1. 

Oriskany sandstone: Albany, Schoharie, Greene, and Ulster counties, N. Y.; Cumber~and, Md.; Virginia; 

Canada. -

1861. Leptocreliajlabellites. Billings, Canadian Jour., vol. 6, p. 351, fig. 126. 

Oriskany sandstone and Corniferous limestone: Haldimand, Canada West. 

Oriskany: Gaspe, Quebec. 

1861. Orthis aymara. Salter, Geol. Soc. London Quart. Jour., vol. i7, p. 68, pl. 4, fig. 14. 

"Silurian:" Valley of Millepaya and other localities on the western side. of the Andes Mountains, Bolivia. 

Devonian: South Africa; Falkland Islands; Gaspe, Quebec. 

1862. Leptocoreliajlabellites. Hitchcock, Portland Soc. Nat. Hist. Proc., vol. 1, pt. 1, p. 79. 

Oriskany sandstone: In belt from Parlin Pond, Somerset County, to Aroostook River, Maine. 

1863. Leptocreliajlabellites. Billings and Logan, Geology of Canada, p. 369, figs. 382, pp. 392, 393, 398, 439, 885. 

Gaspe limestones Nos. 4 and 5 (Lower Helderberg-Oriskany transition): Cape Gaspe, Quebec. 

Gaspe limestone No.8, (Oriskany): Gaspe, White Head, Perce Rock, and Cape Barry, Quebec. 

Gaspe sandstones: Patawegia Brook, near York River; north side of inner basin at Gaspe, and on Douglastown 

River; all on Gaspe Peninsula, Quebec. . 

Corniferous limestone:.West of Grand Riv'er, in Haldimand and Norfolk counties, Canada West. 

1867. Leptocrelia acutiplicata (pars). Hall, P~leontology of New York,' vol. 4, p. 365, pl. 57, figs. 34, etc 

· Corniferous limestone: Waterloo, Seneca County, N.Y. 

1868. Leptocreliajlabellites. Meek and Worthen, Illinois GeoL.Survey, vol. 3, p. 397, pl. 8, fig. 3. 

Oriskany cherty limestone: Dry Fork of Clear Creek, Union County, Ill. 

1874. Leptocrelia jlabellites. Billings, Paleozoic fossils, vol. 2, p. 42, pl. 3, figs. 5, 6. 

Gaspe limestone No. 8, and lower part of overlying Gaspe sandstones: Gaspe Bay, Quebec. 

1 Hall, James, Paleontology of New York, vol. 3, p. 449, 1859. 

2 Idem, p. 450. 

a As a result of the researches of Kayser, Ulrich, and Thomas, this name is generally regarded as a synonym of Leptocalia ji.abellites. Th.e fossil 

as figured by D'Orbigny shows a strongly. convex brachial valve. Such strong biconvexity is not characteristic of Leptocrulia. 
MOLLUSCOIDEA. 

1879. Leptocmliajlabellites. Dawson, Canadian Naturalist, vol. 11, p. 7. 

Nictau iron ore and dark slates (Oriskany): Nictau, Nova Scotia. 

1882. Leptocmliajlabellites. Stevenson, Pennsylvania Second Geol. Survey R.ept. T2, p. 104. 

Lower Oriskany fino-grained dark-blue sandstone: Wills Creek, near Hyndman, Bedford County, Pa. 

1882 . .Leptocmliajlabellites. I. C. White, Pennsylvania Second Geol. Survey R.ept. G7, pp. 86, 297. 

Oriskany cherty beds: Cooper Township, Montour County, Pa. 

1883. Leptocruliajlabellites. Ells, Canada Geol. Survey ~opt. Progress for 1880-1882, pp. 9DD, 13DD. 

Upper Gaspe limeston<::s (Oriskany): Perce Hock, Indian Cove, Grande Greve, and Little Gaspe, Quebec. 

Gaspe sandstone (basal beds): York and Dartmouth rivers, and near Gaspe, Quebec. 

?1884. JJcptoccelia d. L. acutiplicata. Walcott, U. S. Geol. Survey Mon. 8, p. 276. 

JJowcr Devonian: Eureka district, Nev. 

1885. Leptocmliajlabellites. Ells, Canada Geol. Survey Rept. Progress for 1882-1884, pp. 24E, 30E. 

121 

Gaspe Ol'iskany [whether sandstones or upper limestones not stated]: Hills in 'the rear of Gaspe village, Gaspe, 

Quebec. 

Gaspe (lower?) limestones (at contact with Ordovician): Cape Hosier Bay, Quebec. 

1887. Leptocmliajlabellites. Ami, Canada Geol. Survey Ann. Rept., new ser., vol. 2, p. 9N. 

Oriskany slates and sandstones: Campbell River, at junction with Don River, New Brunswick. 

1891. Leptocmliajlabellites. Steinman, Am. Naturalist, vol. 25, p. 856. 

Lower Devonian; North America, Bolivia, Falkland Islands, and South Africa. 

1892. Leptocmliajlabellites. Clarke, Am. Jour. Sci., 3d ser., vol. 44, p. 415. 

Oriskany dark siliceous limestone: Becraft Mountain, N.Y. 

1892. Leptocmliajlabellites. A. Ulrich, Neues Jahrb., Beilage Band, vol. 8, p. 60, pl. 4, figs. 9-13. 

Lower Devonian: Millepaya Valley, west slope of the Illampu Mountains, Bolivia, and elsewhere on the west 

slope of the Bolivian East Cordilleras. 

Icla formation (calcareous or fine-grained rocks): Chahuarani, Icla, Huamampampa, Tarabuco, Chalhuani, Oconi, 

Pulquina, Agua Blanca, and Totora, Bolivia. 

Icla formation (light-gray micaceous quartzitic sandstones): Chililaya, east sicle of Lake Titicaca. 

Sandstone (Icla formation): Rio Chalhuani, Bolivia (D'Orbigny). 

1893. Leptocmliajlabellites. Von Ammon, Gesell. Erd.kunde Berlin Zeitschr., vol. 28, p. 363, fig. 7. 

Lower Devonian: Taquarassu, Matto Grosso, Brazil. 

1893-1895. Leptocmliajlabellites. Hall and Clarke, Paleontology of New York, vol. 8, pt. 2, p. 137 (1893); pl. 53, figs. 40-· 

46, 53 (1895). 

Oriskany: Cumberland, Md.; Falkland Islands (as Atrypa palmata Morris and Sharpe); cordilleras of Bolivia 

(as Orthis aymata Saltet·); South Africa (as Orthis palmata Salter); Matto Grosso, Brazil. 

1895. Leptocmliajlabellites. Ami, Canada Geol. Survey Ann. Rept., vol. 6, p. 15Q. 

Nictau beds (Lower Devonian): Nictau, Nova Scotia. 

1897. A.noplothecajlabellites. Schuchet·t, U. S. Geol. Survey Bull. 87, p. 144. 

Oriskany and Cornilerous: Schoharie and vicinity, N.Y.; Haldimand County, Ontario; Gaspe, Quebec; Cumberland, Mel.; Union County, Ill.; Bolivia; Taquarassu, MattoGrosso, Brazil; Falkland Islands; South Africa. 

1897. Leptocmliajlabellites. Kayser, Deutsch. Geol. Gesell. Zeitsclu., vol. 49, p. 304, pl. 12, figs. 5-6. · · 

JJower Devonian: Chi1alaya, Lake Titicaca. 

Devonian: Pa.lkland Islands; Peru; Bolivia; Brazil; South Africa. 

Oriskany: North America. 

1899. Leptocmliajlabellites. Prosser, New York State Geologist Seventeenth Ann. R.ept. (for 1897), p. 342. 

Oriskany calcareous quartzite: Countryman Hill, Albany County, N.Y. 

1899. A.noplothecajlabellites. Schuchert, Am. Jour. Sci., 4th ser., vol. 7, p. 432. 

Cmnden chert: c~unden and vicinity I Benton County, Tenn. 

1900. Leptocmliajlabellites. Clarke, Mus. Nac. Rio Janeiro Arch., vol. 10, 1899 (English eel., p. 99, 1900). 

lela shales (!;ower Devonian): Ida, Bolivia. 

1900. A.noplothecajlabellites. Schuchert, Geol. Soc. America Bull., vol. 11, pp. 271, 284, 313, 324. 

Shales of the age of the New Scotland and Bect·aft: Devils Backbone, Kreighbaum station (Baltimore & Ohio 

Hnilroad), l\{d. 

Lower Helderberg: Maryland-Virginia region; Gaspe and Nova Scotia. 

rungston beds (Port Ewen) below the Oriskany: Devils Backbone, near Cumberland, ·Mel. 

Oriskany: Oneida and North Cayuga townships, Ontario. 

Monterey formation: About Cumberhu1d, Md. 

J900. LeJJtocmliajlabellites. Clarke, New York State Mus. Mem., vol. 3, No.3, pp. 42, 73, 75, pl. 5, figs. 33-36. 

Oriskany (dark &liceous limestone): Becraft Mountain; Glenerie; near Kingston, on the West Shore Railroad, 

one-half mile southeast of Rondout Creek, N. Y. 

1903. A.noplothecajlabellites. Sclmchert, U. S. Nat. l\fus. Proc., vol. 26, p. 422. 

Becraft limestone: Cherry Run, W.Va. 

Ot·iskany si~iceous shale: Bridge 21, Baltimore & Ohio R-ailroad, near Keyser, Mineral County, vV. Va. 
122 FAUNA OF 'THE CHAPMAN SANDSTONE OF MAINE. 

1903. Anoplotheca.flabellites. Weller, New Jersey Geol. Survey, Paleontology, vol. 3, pp.-98-102, 357, pl. 49, figs. 1, 2. o 

Orbiculoideajervisensis zone, or middle Orlskan) (sillceous limestone): Wallpack Ridge, N.J., 5 miles from New 

York State line. 

Spirijer murchisoni zone, or upper Oriskany (siliceous llmestone): Werden Farm, Nearpass region; three-fourths 

of a mile west of Layton; three-fourths of a mile north of Peters Valley; 1! mlles east of Flatbrookville, all in 

New: Jersey. · 

1903. Leptocreliajlabellites. Van Ingen and Clark, New York State Mus. Bull. 69, pp. 1203, 1207. 

Oriskany (sandy and cherty beds): Glenerie and Rondout, N.Y. 

1903. AnoplothecajlabelWes. Katzer, Geologie des unteren Amazonasgebietes, p. 196, pl. 12, fig. 6. 

Spirifer sandstone: Rio Maecuru, Para: Brazil. 

1903. Leptocreliajlabellites. Reed, South African Mus. Annals, vol. 4, p. 189, pl. 23, fig. 10. 

Bokkeveld series (Lower Devonian): Gydo Pass; just north of Stinkfontein; Ginka Poort; Ceres, South Africa. 

Fossiliferous first or lowest sandstone: North of homestead, Uitkonist, South Africa. 

Devonian: Argentina; Falkland Islands; Bolivia; Brazil; Cape Colony; North America. 

1904. Trigeria (?) oehlerti. Drevermann, Palaeontographica, vol. 50, p. 260, pl. 30, fig. 23 ( cet. excl., not fig. 24). 

Siegen graywacke: Selfen, near Dierdorf, in the Westerwald, Germany (not Herdorf). 

1905. Leptocrelia . .flabellites. Clarke, New York State Mus. Bull. 80, pp. 143, 146, 148, 149. 

Grande Greve limestones: North side of Gaspe Bay. · 

· Perce strata: Perce Rock, Gaspe, Quebec. 

Gaspe sandstone: Gaspe, Quebec. 

1905. Leptocreliajlabellites. Shimer, idem, pp. 206, 228, 229, 234, 253, 254, 264. 

Middle O:r:iskany (zone with Orbiculoideajervisensis) and upper Qriskany, or Spirijer murchisoni zone (both dense 

bh,1e limestones): Trilobite Mountain, N.Y. ·· 

1905. Leptocreliajlabellites. Thomas, Deutsch. geol. Gesell. Zeitschr., vol. 57, p. 264, pl. 14, figs. 35a-c. 

Devonian: Cerro del Agua Negra, Argentina. 

1905. Anoplotheca cf. A. jlabellites. Williams and Kindle, U. S. Geol. Survey Bull. 244, pp. 34, 43, 48. 

"Oriskany" coarse sandstone: Rear of Alabama Row, White Sulphur Springs Hotel, W.Va. (as Leptocrel.ia sp., 

p. 34). 

"Oriskany" soft coarse brown sandstone: Near Chesapeake & Ohio Railway bridge one-half mile west of Clifton 

Forge, Alleghany.Connty, Va. 

A small plano-convex shell of rounded outline with 10 to 14 simple ribs, having adductor 

muscular scars more prominent than the diductors, a massive bilobed cardinal process in the 

flat brachial valve, and a thin, low median septum or elevated line in each valve. ·Pedicle 

valve strongly convex throughout, commonly broadly inflated, rarely subcarinate; the greatest height, which is two-fifths the length ·from the beak, is equal to one-third the length of the 

shell; length occasionally equal to the width, but commonly less in the ratio 6 : 7. Greatest 

width near or slightly anterior to the middle. Hinge line short, c.urved. The posterior margin·of the shell declines .from the rounded beak at an angle of 105° to 135°, commonly nearer 

the latter; cardinal extremities rounded, forming with the lateral and front margins a deep 

curve of more than 180° and nearly 240°. Cardinal area practically lacking; delthyrium 

closed by deltidial plates. On the interior of the pedicle valve the most conspicuous features 

ave the strong rounded teeth, unsupported by lamellre; the unusual feature of the diductor 

cicatrix obscure and the adductor scars fairly conspicuous, much more so than the diductors; 

and the thin, low median septu1n extending one-half to three-fifths the length and apparently 

forking at the anterior end. In internal molds the two large, deep oval holes left by the teeth 

are very conspicuous; they are separated by a little more than their own width; the space 

between the outer margins of the teeth is equal to one-third the width of the shell, or a trifle 

·more. The teeth appear to rise as thick, blunt processes from the base of the valve and are 

not supported by distinguishable lamellre. · The diductor cicatrix is rarely distinguishable but 

appears to be flabellate and a little wider than long. It extends the length of the median septum. The sides of the musculature diverge at an angle of about 90°. The pedicle cavity is 

large. The adductor scar is ov~l, is longer than wide, extends frequently as far forward as 

one-third the length from the beak, and is divided longitudinally by the median septum. The 

median septum is a narrow, sharply elevated line beginning at the forward end of the pedicle 

cavity, becoming conspicuous in passing through the adductor cicatrix, extending half or 

three-fifths the length and bifurcating in front into two short branches, which are extremely 

faint, rarely discernible, 1 to 2 millimeters long, and diverge at an angle of about 60° or more. 

These branches probably serve to limit the anterior end of the musculature. 

/ 
MOLL USCOIDEA. 123 

The brachial -valve is fiat, sometimes slightly conca-ve and sometimes (especially towar~ 

the front) slightly convex. The outline is rounded, the posterior margin di-verging from the 

pointed beak at an angle of about 150° or 155°. The length is equal to or slightly less than 

the greatest width. On the interior of the brachial -val-ve the most conspicuous features are 

the thick hinge plate and the massi-ve lobed cardinal process. The mesial septum in the 

brachial -val-ve is a low, narrow, sharp ridge extending about halfway to the front. It becomes 

thickened in front of the hinge plate where it hal-ves the adductor scar longitudinally. The 

lateral and anterior margins of the scar are indefinable. The cardinal process is massi-ve, occupying a large part of the umbo, and extends backward at an angle of 155° or slightly more 

with the plane of the margin. The lower and main mass of the process is' undivided, but at 

the summit the process becomes lobed. There appear to be four small lobes in perfect specimens. In the molds each crural base lea-ves a sharp, deep pit at the base of the cardinal process. The umbonal region in such specimens presents an appearance similar to that of Megalanteris (" Beachia "), Rensselaeria mainensis, and Nucleospira ventricosa. This indicates 

that the crurre extend directly into the body ca-vity of the animal as in the terebratulids, rather 

than di-verging widely subparallel to the hinge, as in Spirifer and many spire-bearing shells, 

and suggests that Leptocmlia .flabellites m~y after all pro-ve to possess a terebratulid br~chidium. 

The surface is co-vered with 8, more frequently 10, or rarely· 12, radiating ribs (10 to 14 

are usually regarded as the limits in the species), which are strongly ele-vated, rounded to subangular, and separated by interspaces narrower than themsel-ves. A sinus in the convex pedicle 

valye and a fold in the fiat brachial-val-ve are commonly but not invariably present. The sinus 

in the pedicle -valve is produced most frequently by the disappearance of the median rib, but 

very commonly the bounding rib on each side is a little strengthened; the media~ rib may 

then also be present, but 1nore or less obsolescent, appearing as a riblet in the sinus. The fold 

in the brachial -val-ve is produced by the strengthening of the two 1nedian ribs. The groo-ve or 

interspace between these two ribs is slightly wider and deeper th~n the groo-ves between the 

other ribs. One or two concentric -varices of growth are commonly obser-vable. No finer sur-

. face ornamentation has been seen. Shell structure finely fibrous; impunctate under a hand 

glass. The common size of the pedicle -val-ve is 11 or 12 millin1eters long and 13 or 14 millimeters wide. The largest specimen obser-ved was 14 millimeters- long and 17 millimeters wide. 

Leptocmlia flabellites· occurs in North America, South America, and South Africa in rocks 

of the age of the Oriskany sandstone and also in the younger "zone of 81)i1vijer hercynire." 

Apparently' it extends upward into the "Corniferous" in Ontario. It is abundant and a dominant 1nember of the fauna where-ver it occurs; it is particularly so in the Moose Ri-ver sandstone. It has been :found in this formation at Parlin Pond (locality 1059 C3

), ~1oosehead Lake 

(locality 1076 E3), and Detroit (locality 1100 A): all in Somerset County, ~1aine. 

U.S. National Museum, catuJogue No. 59756. 

Oomparisons.-The Maine specimens are distinguished for ha-ving the ·1ninin1un1 number 

of plications, which are rounded. In Illinois, South Allerica, and South Africa the species is 

represented by larger indi-viduals with more angular ribs, the number of which is commonly 

the 1naxin;Ium for the species, 12 or 14. The Gaspe specimens also ha-ve 12 or 14 ribs. 0 The absence of Leptocmlia flabellites h1 Europe is worthy of special note. In the norn1al 

Oriskany fauna of New York, New Jersey, Pennsylvania, ~1aryland, a:nd Virginia, as well as 

in such other fau~1as as seen1 to represent the younger "zone of Spi1·ijer hercynire" (as at Gaspe, 

Quebec; in Nova Scotia; in Somerset County, Maine; in Appalachian Pennsylva.nia to MarylMld; i.n Illinois aJld Tennessee; on Rio Maecuru, Para, Brazil; in Argentina; the Falkland 

Islands; and South Africa), Leptocrelia is one of the most abu;ndaJlt and dominant eleme11ts 

of the fauna. It seems· therefore remarkable that this species, so abunda~1t, very frequently 

forming of itself thick 1nasses, in A1nerica and South Africa, should be unrecorded frmn rocks 

of silnilar age in Europe. · 

It is probable that in Europe the ·species is absent or extremely rare, else it would have 

been reported lo11g ago. Oxtly withb1 the last few years have any fossils been reported from the 

European fauJlas that caJl be closely con1pared with Leptocmlia flabellites. One of these, which 
124 FAUNA OF THE CHAPMAN SANDSTONE OJ! MAINE. 

seems to be identical with this cosmopolitan species, is Trigeria? oehlerti DrevermaP.P./ from the 

Siegen graywacke of Seifen, near Dierdorf, in the W esterwald. The fossil as figured by Drevermann has a depressed convex valve and is subcircular in outline, with a fold produced by two 

s,..trong ribs, and on each side there are four slightly smaller rounded ribs. The internal n1old 

figured by Dreverman.n has much the sam,e aspect as the specimens of Leptocmlia flabellites 

occurring in the faunas of Somerset County, Maine, and his figure shows at the umbo a peculiar 

expression similar to that occurring in internal molds of L.flabellites and produced by the massive 

cardinal process. (Compare some of the figures in the present work.) Drevermann's species 

seem to represent the phase of L. flabellites represented by the Maine. fossils-that is the 

pauciplicate type with small shell and only 8 or 10 rounded ribs. Drevermann gives a scanty 

description of the fossil, and though ordinarily I should feel much hesitancy in uniting with a 

transcontinental species a European fossil known practically only from a single figure of a 

fragmentary brachial valve, yet so peculiar are th.e features of Leptocmlia flabellites that it is 

safe to call attention to Trigeria? oehlerti Drevermann s. str. (not his fig. 24) as its possible 

European representative. 

Drevermann illustrated in his figure 24 a form fron1 the Siegen graywacke CUnter 

Coblenzian ~) of Herdorf, h1 the Westerwald, whic4 he provisionally regarded as cospeci:fic 

with Trigeria? oehlerti from Seifen. The Herdorf fossils are, however, very distinct, having 

the fold in the pedicle valve and the sinus in the brachial valve and being in this respect similar 

to Oentronella ( Trigeria) bergeroni Oehlert from the French Eo-Devonian. In Leptocmlia 

fiabellites and the Seifen fossils the fold is in the brachial valve. The Herdorf fossils also appear 

to have 16 or 18 ribs. 

Genus MERISTELLA Hall, 1859. 

MERISTELLA cf. ¥. BELLA Hall. 

Plate VI, figures 16, 19, 20. 

1857. Merista bella. Hall, New York State Cab. Nat. Hist. Tenth Ann. Rept., p. 92, figs.1-7. 

Shaly limestone of the Lower Helderberg: Albany County, N. Y. 

1859. Meristella bella. Hall, Paleontology of New York, vol. 3, p. 248, pl. 40, fig. 1. · 

Shaly limestone of the Lower Helderberg: Helderberg Mountains, Schoharie, Carlisle, and elsewhere in New 

York. 

?1891. Meristella bella. Whitfield, New York Acad. Sci. Annals, vol. 5, p. '510, pl. 5, figs. 8-10. 

Lower Helderberg hydraulic limestone: Greenfield, Ohio. 

1895. Meristella bella. Hall and Clarke, Paleontology of New York, vol. 8, pt. 2, pl. 43, figs. 7-9; pl. 44, figs. 1-3. 

Lower Helderberg: Helderberg Mountains and Schoharie, N. Y. 

?1895. Meristella bella. Whitfield, Ohio Geol. Survey, vol. 7, p. 412, pl. 1, figs. 8-10. 

Lower Helderberg (?)2 hydraulic limestone: Greenfield, Ohio. 

1897. Meristella bella. Schuchert, U. S. Geol. Survey Bull. 87, p. 266. 

Lower Helderberg: Albany and Schoharie countie~, N. Y.; Greenfield, Ohio; Lake Temiscouata, New Brunswick. 

1899. Meristella bella? Prosser, New York State Geologist Seventeenth Ann. Rept. (for 1897), p. 350. 

New Scotland shaly limestone: Oniskethau Creek section near Clarksville, Albany County, N.Y. 

1900. Meristella bella. Schuchert, Geol. Soc. America Bull., vol. 11, p. 284. 

Lower Helderberg (New Scotland): NewYork, Maine, and New Brunswick. 

1905. Meristella cf. M. bella. Williams and Kindle, U.S. Geol. Survey Bull. 244, p. 48. 

Sandy and cherty beds: Southern Railway, near Big Stone Gap, Wise County, Va. 

Two gibbous pedicle valves in the collections of the Chapman fauna are referred with 

doubt to the genus Meristella and species }l.. bella Hall. They are of small size, ovate outline, 

and without any definable sinus in the pedicle valve, though the anterior margin is constricted 

for a short distance in the middle, indicating that a faint sinus may possibly exist in the brachial. 

valve. The posterior margin is obtuse (95°-115°). The greatest width at the well-rounded 

shoulders is near the midlength of the shell and the length is equal to the width. The umbo is 

well inflated. On the interior of the pedicle valve the muscular scars are well developed. The 

oval pedicle musculature with a narrow impressed median line extends one-third the length 

1. Palaeontographica, vol. 50, p. 260, pl. 30, fig. 23, cet. excl., not fig. 24, 1904. 

2 This horizon appears to be about that of the Manlius I imestone. Associated with several species of Helderbergian aspect are Spirifer vanuxem~ 

and some Silurian fossils. 
MOLL USCOIDEA. 125 

of the valve and is surrounded by a slightly elevated rin1; from its front end the diductor scars 

extend in a triangular ftabellate.r>atch, strongly striate radially toward the front, with the sides 

d.ivm:ging at an angle of 90°. The musculature extends _three-fourths the length of the shell 

frmu the beak. In the ruusculature of ~1eristella bella figured by Hall and Clarke/ the front 

does not extend more than three-fifths the length from the beak, but the sides diverge at a 

right angle, as in the present sp~cimen. In another individual of ~1.. bella frmn the New Scotland limestone of Clarksville, in the Helderberg Mountains (Cornell University Museum collections No. 186), the musculature extends three-fourths the length or more, as in the Maine 

speciJnens, but the margins are acute, diverging at 60°. . 

In the small size, transverse outline, absence of a strong sinus in the pedicle valve, and 

probable occurrence of a slight sinus in the brachial valve, 2 the present forms approach J.l{eristella, bella,, and the musculature is also similar. The sinus, which is generally present, though 

n1ore or less obscure, in the anterior surface of the pedicle valve of ~1. bella, is not present in the 

two Chapman pedicle valves exa1nined; it is also occasionally absent in New York specimens 

of I-Iall's species. The Maine specin1ens are provisionally referred to ~1. bella Hall. 

Localjty: Chapn1an sandstone, west side of Edmunds Hill, Chapman Township, Aroostook 

County, Maine. 

U.S. Nationall\iuseun1, catalogue No. 59757. 

Oomparisons.-~1eristella bella is a remarkable little species distinguished from the nonnal 

Meristellre of the Silurian and Devonian by its smaller size and by the usual occurrence of a sinus 

in both valves at the front rnargin. 3 In these .rather important respects, ~1. bella agrees with 

I-Iinclella (Whitfieldella of authors). Superficially the species is similar to the ~1erista (Whitfielr.lell<t) oblata of Hall, the only distinction being that the insinuation is generally slightly 

deeper in ~1. bella. 

In external appen.rance these species differ little from the European Silurian (Gothlandian) 

Meristella ( Whitfielclella or Hinclella 4 ) clidyma (Dalman) of Davidson and authors, 5 the external appearance, the musculature, and the septal feature being remarkably similar. !-lowever, in the genus Meristella the jugun1 has a circular loop on each side, but this circular loop 

is absent in Whitfieldell~, where the jugum· ends in a simple straight spur. Hall and Clarke 6 

state definitely that the l\1eristella type of brachidiurn,- with a circular loop added to each side 

of the jugum, has been observed in ~1.. bella, so that this species is a true Meristella, whereas 

l;Vl~itjielclella oblata is a typical form of Hind ella (Whitfieldella), as is also Ilinclella (Whitfield ella) 

(liilyma of authors. 

Genus PENTAGONIA Cozzens, 1846. 

PENTAGONIA ( ~) sp. indet. 

Plate. VI, figure 24. 

cf. 1904. Athyris sp. nov. Drevermann, Palaeontographica, vol. 50, p. 259, pl. 30, figs. 20, 20a. 

Siegen (?)graywacke: Unkel, Germany. 

Lower Coblenzian ("?)graywacke: Herclorf, Germany. 

An internalrnold which presents such interesting characters that, fragrnentary and very 

imperfect as it is, it has been figured· in this report. The remarkable feature is the low, broad, 

1 Paleontology or Now York, vol. 8, pt. 2, pl. 44, fig. '1, 1895. 

2 A l.>ruchi::\1 valve (see Pl. VI, fig. lG) of a l\1cristclla of the same size and proportioQS as the forms under discussion and probably representing 

tho same species has since l.>ccn rowlCl in tho collections from the same locality (1099 M:). It shows the front margin slightly insinuate, with a very 

faint short sinus and a do pressed convexity of the anterior two-fifths or the valve. Tho specimen, which is an internal mold, sho-.vs a strong median 

sop tum ox tending three-fifths the length. The posterior -margin diverges from the beak at an anglo or 95 o. The greatest width is distinctly well in 

front or tho middle; width, 16 millimeters; length, 16 millimeters. Of the other specimens, one is 111.5 millimeters long and wide, and the other 

16 mill imotcrs. 

a Tho little Meri$tella meta Hall and Clarke, from the Hamilton of New York, also has an insinuation at the front in both valves, thus agreeing 

with Whitficldclla. 

4 Whitfieldclla and Hindolla are now regarded as essentially identical. (See Schuchert, Charles, in Eastman's American edition or Zittel's Textbookorpaleontology,<Vol.1, p. 338, 1900.) Hindella is the older term and has priority. 'l'he Whitfieldellas may be distinguished superficially 

from Uindolla in having the front margh1 insinuate, but no internal distinction is known. 'l'he insinuation of the margin is apparently a character 

variable in tho same species. 

o Probably not Dalman's species. In the Gotland Island Whitfieldcllas which furnished Dalman's types the umbo in the pedicle valve is elevated 

nbovo that or tho brachial valve, thus entirely exposing the large dclthyrium and the deltidial plates. (Sec Hall, James, and Clarke. J. M:., Paleontology or Now York, vol. 8, p. 60,· pl. 40, figs. 14, 15, 1895.) Such a form docs not occur in America, nor apparently in England. 

o Op. cit., p. 78. 
126 FAUNA OF THE CHAPMAN SANDSTONE OF MAINE. 

rou:t;1ded fold which occupies most of the width of the valve. On each side near the lateral 

margin is a shallow sinus or flat area; the ~xtreme lateral margin is ridgelike and abruptly 

inflected. This remarkable curvature recalls the form of Pentagonia unisulcata,t but the present 

specimen has a much lower and more rounded fold without any groove or sinus, 2 and the valve 

as a whole is very depressed convex. The figure shows the impressions of what appears to 

have been a simple spindle-like cardinal process, and no median septum is preserved. In these · 

respects the shell seems distinct from Pentagonia. The figure also shows the impression of what 

seems to be the adductor musculature. 

Locality: Chapman sandstone, Edmunds Hill, Chapman Township, Aroostook County, 

Maine. 

U.S. National Museum, catalogue No. 59758. 

Oomparisons.-The remarkable curvature of this fossil recalls, still more closely than it 

does Pentagonia unisulcata, the peculiar Athyris n. sp. of Drevermann, cited above, from the 

Lower Coblenzian 0) of Herdorf, and also his Athyris aliena 3 from the ·siegen graywacke of 

Seifen. These Athyris species, characterized by a broad fold in the brachial valve and a broad 

distinct sinus on each side, form a natural, easily recognizable group ranging from the lowest 

Devonian to the Upper Devonian and occur throughout Europe. In America Pentagonia unisulcata and. the present fossil are the only representatives of this interesting group, except, 

perhaps, the peculiar Atrypina sp. described by Clarke 4 from the St. Albans beds of Griffon 

Cove, Quebec. 

MOLLUSCA. 

Class PELECYPOD.A Goldfuss. 

Order PRIONDESM.ACEA Dall. 

Family SOLENOPSID.tE Neurnayr. 

Genus ORTHODESMA Hall and Whitfield, 1875. 

The genus Orthodesma was founded in 1875 by Hall and Whitfield 5 to include transversely 

elongated shells having typically the length equal to more than twice the height and resembling 

Orthonota Conrad and Palreosolen Hall. in the subparallel ventral and dorsal margins. In the 

latter genera the hinge is _continued in a straight line both behind and in front of the beaks, 

whereas in Orthodesma the hinge line is more or less interrupted and deflected in front of the 

beaks by a lunule. The original diagnosis of the genus follows: . 

More or less elongate bivalve shells, having the hinge line straight and generally extended posterior to the beaks 

but contracted or bent beneath or anterior to them; hinge plate apparently edentulous; valves united by an external 

ligament extending to a greater or less distance along the posterior cardinal margin. Posterior muscular scar elongate 

ovate; anterior scar smaller; both faintly marked; pallial line simple. Shells thin, marked externally with irregular 

concentric plicre. Type, Orthodesma recta. 

In 1894 the genus was redefined and ·restricted by Ulrich, 6 who added as one of the generic 

character::; a very slight gape anteriorly and posteriorly. The Chapman 1naterial is not well 

enough preserved to add to our knowledge of the structure qf the genus, but the present species 

is the first recorded above the Ordovician in America.' 

0RTHODESMA CARINIFERA sp. nov. 

Plate XIX, £g{ue 2. 

Outline transversely elongate, length about three times the height. Greatast length below 

the middle; greatest height at the posterior fifth or sixth. Beaks situated near the anterior 

1 See Paleontology of New York, vol. 8, pt. 2, pl. 42, figs. 22-32, 1895; also Schuchert, Charles, U.S. Geol. Survey Bull. 87, p. 302,1897. 

2 Hall and Clarke (Paleontology of New York, vol. 8, pt. 2, figs. 25, 26, 1895) figure a specimen of Pentagonia unisulcata·'rrom the Hamilton ol 

Centerfield, N.Y., which has a low rounded fold without any median sinus, but even this is much more gibbous than the specimen at hand. 

a Drevermann, F., Palaeontographica, vol. 50, pl..30, fig. 19, 1904. 

4 Clarke, J. M., Early Devonic history of New York and eastern North America: New York State Mus. Mem. 9, p. 109, pl. 29, fig. 18, 1908. 

6 Hall, James, and Whitfield, R. P., Paleontology of Ohio, vol. 2, p. 93, 1875. 

OUlrich, E. 0., Paleontology of Minnesota, vol. 3, pt. 2, p. 516, 1894. 
MOLLUSCA. 127 

end, nearly but not quite terminal. In front of the beaks the anterior .margin descends in a 

gently convex, almost vertical line, rounding off. into the ventral margin. The latter is almost 

straight and descends as far as the postumbonal extremity, which is subangular. The posterior 

margin is·s~ightly retrorse, nearly vertical, and gently convex. Hinge extremity obtusely subangular. The hii1ge line is straight and rigid, slightly less 'than the length of the shell, but 

longer than twice the height of the shell. The dorsal and ventral margins diverge posteriorly 

at an angle of less than 20°, so that the maximum height near the postventral extremity is 

equal to twice the height of the shell at the beaks. Beaks inconspicuous, depressed to the hinge 

line and not protruding beyond. A con.spicuous feature of the shell is an ele.vated rounded 

carination recalling to some extent the genus Goniophora, extending from the beaks to the post-

~entral extremity. This carination is sigmoidal, mostly convex, to the hinge line. The greatest 

depth of the valve is situated at the midheight on the carination, and at the anterior third of 

the length; the depth is equal to half the height of the valve. A very faint sinus or depression, 

not shown in the figure, extends from the beak ventrally and backward, at an angle of 45° with 

the hinge. Midway between the carination and the hinge line there is, in the right valve, a faint 

ridge, somewhat as in .the genus Sphenotus. Ligament, external ( ~). Dentition and muscular 

scars not observed. The typ .. e specimen, a clean internal mold of the right valve, shows neither 

muscular scars nor any trace of posterior lateral teeth. . 

The surface ornamentation consists of extremely faint con'centric lines of growth. 

The type and only specimen, a right valve in internal mold, is 14.75 millimeters long, 5! 

millimeters high, and nearly 3 millimeters de.ep. · 

Locality: Chapm.an sandstone, 2 miles west of Presque Isle Stream, Chapman Township, 

Aroostook County, Maine. · 

U.S. National Museum, catalogue No. 59759. 

Oomparisons.-In the long, straight, rigid hinge line, transversely extended form, expanding height posteriorly, anterior beaks, and surface carination, the species bears a cl9se Tesemblance to S1Jhenotus? gorceixi (Clarke)/ but the Maine fossil is more rapidly contracted in height 

toward the front. The surface carinations and general outline of Orthodesma carinifera present 

superficially a resemblance to the genus Sphenotus Hall; but Sphenotus as described by Hall 2 

has two cardinal teeth in the right valve, one or two posterior laterals, and a strong anterior 

muscular scar, agreeing in these respects as well as in superficial appearance with the Silurian 

to Permian genus Pleurophorus King. Most of the species of Sphenotus, however, show no 

trace of teeth or umbo.nal scars, but whether this is due to poor preservation can not be stated. 

Certainly Orthodesma carin'ifera appears superficially congeneric with those shells which have 

the typical Slu·face cari.nation and general superficial appearance of Sphenotus, but in which no 

teeth have been observed. These Sphenot~ are v,ery closely allied to the usually noncarinated 

Orthodes1na; indeed the noncarinated, so-called Sphe,notus solenoides Hall 3 appears to be a 

typical Orthodesma. 

Family GRAMMYSIIDJE Fischer. 

The following genera and species of Gram1nysiidffi are recognized in the Chapman fauna: 

G1·amm,yiia aca.dica Billings. 

Grmnmysia (Grammysioidea) modiomorphm Clarke. 

G. ( Grmnmysioidea) elym,elloides sp. nov. 

Elymella harrisii sp. nov. 

Glossites barmndii sp. nov. 

Glossites amnigenoides sp. nov. 

Glosaites sp. indet. 

From the :Moose River sandstone fauna an allied form is described as Grammysia (Grammysioidea) princiana sp. nov. 

r Clnrko, J. l\L, Tho Pnleozoic fntmas of Para~ Brazil; The Devonian Mollusca of the State of Para: Mus. nac. Rio de Janeiro Arch., vol. 10, 1899 

(author's J~r:~glish od., p. 59, 1900), pl. 5, figs. 14-16. The species is from the Erere Meso-Devonian. 

s Hnll, .Tamqs, Paleontology of Now York, vot. 5, pt. 1, No.2, p. 33, 1885. TypeS. contractus (Hall). Hall mentions S. arcaiformis and S. contractns as 11 examples of tho genus," but only the latter shows the dentition described. 

Bldom, p. 398, pl. 65, figs. 21-29; Ham~.lton group, New York. 
128 FAUNA OF ·THE CHAPMAN SANDSTONE OF MAINE. 

Genus GRAMMYSIA De Verneuil. 

History.-The lamellibranch genus Grammysia was founded by De Verneuil 1 in 1847. 

A translation from the French of the original description is as follows:· 

Gr.ammysia hamiltonensis No. 6.-Beingunable to neglect this species, which is of great importance on account of the 

extent of its distribution, and finding no genus into which it can conveniently enter, we have thought it necessary to 

establish for it the genus Grammysia, which we would characterize in the following manner: Shell equivalve, inequilateral, not gaping, furnished with two very unequal muscular impressions; pallial impression rounded posteriorly, 

terminating at the large muscular scar in such a way as to leave two-thirds of the latter outside [the pallial line]; ligament 

external, quite prolonged in the depression. of the corselet; surface traversed by an oblique rib, which extends from the 

beak to the middle of the lower margin, and by several concentric rounded folds. Through the inequality of its muscular impressions and through the form of the pallial impression, this shell, it seems, ought to be placed near the Cypricardias and the Cyprinas. This genus, so well characterized by the median rib which traverses the valves, includes 

several species, of which one has been called Nucula cingulata by Risinger. 

The Grammysia hamiltonensis is distinguished from theN. cingulata, which is found in Gotland and at Dudley, by 

its less transverse form and by the position of its beaks farther removed from the external border [beaks more incurved]. It is abundant in the Hamilton group (New York) and is found in Europe in the Nehou limestone (Manche) 

and in the graywacke of Daun (in the Eifel). 

Verneuil gives three figures of left valves from· the localities indicated. 

Type species.-The type species of Grammysia is universally"recognized as the Grammysia 

hamiltonensis of De Verneuil and not G. cingulata Risinger. This is made evident by the very 

words of De Verneuil: Being unable to neglect this species [G .. hamiltonensis] * * * we have 

thought it necessary to establish for it the genus Grammysia." What the types of Grammysia 

hamiltonensis De Verneuil may have been, however, is another problem, which must be answered 

before the type species of De Verneuil's genus can be fixed. · It is to be noted that De Verneuil 

regarded as representative of a single species, which he called G. hamilton.ensis, shells from the 

Hamilton (Middle Devonian) of New York, from the Nehou (Lower Devonian) limestone of 

Normandy, and from the Daun graywacke (Lower Coblenzian or middle Eo-Devonian) of the 

Eifel. 

These American, French, and German shells are now known to represent not a single species 

but certainly at least two, and probably three, distinct forms. The American form from the 

New York Hamilton had been previously described by Conrad 2 as Pterinea bisulcata, and in 

America Conrad's specific name has been adopted, so that the shell is here known as Grammysia bisulcata (Conrad). Among German paleontologists De Verneuil's name Grammysia 

hamiltonensis has been in general usage, particularly in the earlier decades; but Hall 3 showed 

that the German forn1 of De Verneuil's Grammysia hamiltonensis is Goldfuss's old species Pholadomya anomala. 4 The shells which Beushausen 5 regards as identical with Goldfuss's species 

differ from the American G. bisulcatus in the more iiTegular and compressed ornamentation, 

and to emphasize thi.s distinction Beushausen proposed for the Rhenish shells the name Grammysia anomala var. rhenana. Whether Beushausen's forms are really those included by De 

Verneuil under G. hamiltonensis is open to some doubt. De Verneuil's German form of Grammysia hamiltonensis came from the vicinity of Daun, in the Eifel-presumably from the Lower 

Coblenzian at Upper and Lower Stadtfeld, as these were the best-known Daun localities. ·certainly De Verneuil's types can1e from the Daun district, whereas none of Beushausen's Grammysia 

anomala var. rhenana are recorded from Daun. Beushausen's form is described from the 

Upper Coblenzian at Daleiden and the Lower Coblenzian at Nellenkopfchen. Beushausen 

records from Daun (Gemiind) Grammysia marginata (Goldfuss), G. nodocostata var. eifeliensis, 

G. ovata (Sandberger), and G. abbreviata (Sandberger). Drevermann 6 records all these Daun 

species from Oberstadtfeld, ne~r Daun, except G. abbreviata (Sandberger), and adds G. irregularis Beushausen (~)and G.lcevis Drevermann nov. De Verneuil's Daun material seems to have 

1 Remarques sur les fossiles paleozoiqu~s communs a 1' Amerique et a l'Europe, et sur les rapports qu'ils ofirent dans leur distribution: 

Soc. geol. France Bull., 2d ser., vol. 4, p. 696, 1847: · 

2 Conrad, T. A., New York Geol. Survey First Ann. Rept.,p.116, 1838. 

a Hall, James, Paleontology of New York, vol. 5, pt. 1, p. 359, 1885. 

4 Goldfuss, August, Petrefacta Germanirn, p. 272, pl. 157, fig. 9, 1834-1840. 

6 Deushausen, Louis, Die Lamellibranchiaten des rheinischen Devon: K. preuss. geol. Landesanstalt Abh., new ser., vol. 17, p. 237, pl. 22, 

figs. 8-10, 1895. 

6 Palaeontographica, vol. 49, p. 93, 1902. 
MOLLUSCA. 129 

coincided rather with shells having more down-curved beaks, more retrorse posterior margin, 

and n1ore regular concentric plication anterior to the cincture; in fact, the shells are identical 

with those figured by Beushausen as Grammysia ovata Sandberger, 1 from the Lower Coblenzian 

of Gemiid, near Daun, and as G. irregularis Beushausen nov.,2 from the Lower Coblenzian of 

Nellenkopfchen, near Coblenz. 

The French for1n of De Verneuil's Grammysia hamiltonensis h~s been separated by Oehlert 

as a distinct species under the name Grammysia cotentina Oehlert, 1881, so that we find to-day 

a general disagreement as to what forms, if any, should take the name Grammysia hamiltonensis 

De Verneuil (the consensus of opinion seems to be that the name should not be used), and what 

should be regarded as the types of G. hamiltonensis, either in the interpretation of De Verneuil 

or in a restricted use of De Verneuil's specific name. 

The types of Grammysia hamiltonensis in the interpretation of De Verneuil were certainly 

fro1n the I-Iamilton of New York, not from Nehou, in La Manche, nor from Daun, in the Eifel, 

as is proved first, by the name of the species ;.second, by the fact that the Hamilton of New York 

is the first locality cited, and.a specimen from it is the first one figured; and third, by the fact 

that the pap~r in which the species is described is one treating of American fossils. It is, therefore, certain that the fossils which De Verneuil called G. hamiltonensis were lamellibranchs which 

are fairly abundant in the Hamilton of New York, and that for these New York shells the name 

was proposed and used. The Nehou and Daun Grammysias were regarded by De Verneuil 

as identical with the New York forms. Hence it follows that although Grammysia hamiltonensis De Verneuil, so :far as the New York specimens are concerned, is a synonym of G. 

bis'l.tlcata (Conrad), De Verneuil's name need not be applied to either the French or the German 

fonns if these are distinct. There is additional warrant for restricting the use of the specific 

name hamiltonensis in the fact that De Verneuil's species was not sufficiently described or 

figured to enable one to recognize the particular species intended. The names applied by the 

Gern1an paleontologists and by Oehlert in France will, therefore, hold good for the European 

shells regarded by De Verneuil as identical with the New York Hamilton forms. 

Another preliminary difficulty which must be overc01ne before :fL-x:ing the type of Grannnysia 

is the fact that although G'rammysia hamiltonensis De Verneuil may be, and in fact is, admitted 

to be identical with the common Hamilton Grammysia bisulcata of Conrad, the shells which 

I-Iall calls Grammysia bisulcata are quite evidently not all cospecific.3 As has been pointed out 

by Beushausen,8 if we were to consider, as I-Iall did, that figures 6, 7, 15, and 16 on his plate 54 4 

represent a single species, then the advance made in the last two score years in our conception 

of a species 1nust be abandoned. If a typical form of Grammysia bisulcata (Conrad) is to be 

selected it will have to be that represented by flail's figure 7, plate 54, and with it might be 

included under the same specific name the specin1ens represented in his figures 10, 11 (a crushed 

specimen), 12, 13, f,tnd possibly a few others, but not that shown in figures 5, 6, 15, and 16. 

The typical forms of Gramm,ysia bisulcata as thus selected are not only the commonest types 

of the species in the I-Iamilton, but they also include the forn1 figured by De Verneuil as Gram-

?nysia hamiltonensis, for it must be apparent to the bluntest discernment that De Verneuil's 

figure 1 is indistinguishable specifically from Hall's figure 7. Finally they conform with Conrad's diagnosis of the species. The distinguishing featu~·es of the species are the strong cincture 

which distorts the basal1nargin; the long hinge line, which is only slightly reclining; the retrorse 

posterior margin; the transversely extended outline; the concentric strire covering the entire 

surface and raised into distinct concentric folds; and the obliquity of the shell. 

In lack of any other known information as to the types, the specimens shown in Hall's 

plnte 54, figures 7, 10, 12, and 13, may be taken as the types of Grammysia bis'l.tlcata (Conra.d), 

1838 (=G. hamiltonensis De Verneuil, 1847)~ and therefore as the types of the genus Grammysia 

De Verneuil, 1847. With the types thus definitely and precisely fixed we can draw up the 

following revised description of Gram1nysia. De Verneuil: 

I Beushausen, Louis, op. cit., pl. 19, fig. 2. 

2 Idem, pl. 20, fig. 2. 

5024~ --~0.89--16----9 

s Idem. p. 227. 

4 Paleontology of New York, vol. 5, pt. 1. 
130 FAUNA. OF THE CHAPMAN SANDSTONE OF MAINE. 

Lamellibranch shells of rather large size, equivalve except for the alternation of a fold 

and sulcus in each valve, sometimes duplicated. Frequently, on account of compression in 

the rock, apparently inequivalve, but that this inequality is not real and is due to posthumous 

pressure is indicated by the facts that uncrushed specimens are equivalve and that in crushed 

material sometimes on~ valve is the larger and sometimes the other. Fold and sulcus pass 

from the beak 'nearly to the middle of thebasal margin; very strongly inequila.teral, oblique, 

transversely, or obliquely ovate. Margins not ·gaping, though on account of the strong ligament, many .shells have been pulled open after the death of the animals and have been fossilized 

in this condition, so that they appear to be open behind, but this gaping is more apparent than 

real, for specimens may be found entirely closed. Beaks anterior,.prominent, incurved, directed 

forward. Cardinal line distinct, straight, or slightly arcuate, reclining or nearly horizontal; 

posterior margin retrorse; basal margin arcuate, more or less constricted near the middle or 

post-ventrally by the fold and sulcus, as already indicated; anterior portion of the shell distinct; 

lunule very well developed. Apparently edentulous, or with an obscure obsolescent fold under 

the beak. Muscular scars rarely retained; the anterior one situated under the lunule, fairly 

large, though only about half the width of the posterior scar, or slightly more. Pallial line 

simple; beginning at the anterior third of the large scar, it extends downward and backward, 

then curves par!1llel to the basal margin, reaches upward and forward to about the middle of 

the· anterior muscular ·scar; pallial impression radially striate when well preserved. Surface 

features comprise concentric folds, more or less irregular posterior to the sulcus, less irregular 

anteriorly and on the umbones; covered with more or less obsolescent concentric strire. 

Limits of Grammysia.-The general configuration of these shells is well known, but owing 

to the unrestricted use of the generic name in Hall's more advanced work s01ne misconceptions 

as to the limits of the genus may arise. In the first place, the radial fold and sulcus furnish one 

of .the most important features of the genus, as was noted by De Verneuil 1 when he used the 

expression "This genus, so well characterized by the median rib which traverses the valves." 

De Verneuil, in fact, included in his genus only those Silurian and Devonian forms which have 

a well-developed fold and sulcus, and the name Grammysia will have to be restricted to grammysioid shells having this feature. Although the radial fold and sulcus are represented by 

nearly all stages of development, from the well-developed type of De Verneuil's form to that 

shown in Grammysia circularis I-Iall,Z in which the fold and sulcus are with difficulty apparent, 

it is nevertheless true that the name Grammysia can be and really ought to be restricted to 

those shells in which the fold and sulcus are developed, at least in some stage of the life history; 

and it is obvious that those so-called '' Grammysias" 3 which have no indication whatever of 

the fold and sulcus or of any strictly corresponding structures at any· period of their existence 

can not be included in Grammysia-particularly as several well-defined genera already exist 

in which these shells may very well be included. A few of these genera ar.e n1entioned below, 

but as the present work is not intended as a monograph on Paleozoic lamellibranchs, only the 

briefest mention will be made of the forms that. do not occur in the Chapman fauna. 

In the first place, we may separate from Grammysia those genera usually confounded 

with it, such as Alloris1na or Allerisma King and Chrenomya Meek (Carboniferous, Permian), 

Pholadomya Sowerby (Mesozoic and Cenozoic), Pleuromya Agassiz or Myacites of authors 

(Triassic to Lower Cretaceous), and Sanguinolaria Lamarck (Cenozoic)-shells which are both 

gaping and sinupalliate. Leptodomus McCoy, 1844, differs from .Gramn1ysia in the gaping 

anterior and posterior extremities (the posterior gape is especially well defined), and in the 

absence. of the radial fold and sulcus, which are, however, represented by a radial undefined 

sinus extending from the beak obliquely to the basal margin. 

Sedgwickia McCoy, 1844, is like Leptodomus but has no radial sinus, and the beaks are 

usually directed less anteriorly, more vertically. 

Sanguinolites McCoy, 1844 (not De Koninck, 1885 = Sphenotus Hall, mostly), is like Sedgwickia· but very long drawn out transversely; gaping behind, not in front, and with a distinct 

retractor muscular impression above the strongly marked anterior cicatrix. 

1 Op. cK, p. 696. 2 Paleontology of New York, vol. 5, pt. 1, pl. 57, figs. 3, 4, 1885. a Idem, pls. 59-62. 
MOLLUSCA. 131 

Cimitarin. I-In.ll, 1869-70, is apparently gaping only behind, like Sanguinolites; it has a 

very long dra,vn out transverse outline; musculature not strongly impressed, character unknown. 

The shells are distinguished superficially by the curved Solen-like or cimitar-like form and by 

the presence of a posterior carination and distinctly demarcated postumbonal slope, somewhat 

as in Goniophora. 

Distinct from the gaping shells of the above types is a second strongly marked group separated frmn Grmnn1ysia by I-Iall and Whitfield 1 in 1875 under the name Cuneamya. Cuneamya 

includes closed grammysioid shells without indications of radial sulcus, having the um.bones 

tumid, terminal or nearly so, and directed strongly forward. The shells are transversely elongated or oblong. A lunule is present but not well devf}loped. The ligamenta! groove is well 

developed. There are no teeth or hinge plate, according to Ulrich.2 A large number of Upper 

Ordovician species are included in this genus. . It may continue higher into the Silurian 3 and 

possibly into the Lower Devonian or even higher. 

Sphenomya Hall, 1883, resembles Cuneamya in general expression but has no ligamenta! 

groove. The typical species is G. (S.) cuneata I-Iall from the Hamilton of New York. Leptodom'u,s truncata McCoy, from the Upper Ludlow of Westmoreland, is congeneric.4 A few species 

described by De Koninck 5 under Edmondia, and Sanguino1ites may possibly belong here, as 

well as Grarrmnysia 1Jrrecursor Hall, from the Schoharie grit. 

Protmnya I-Iall, 0 1885, is like Cuneamya, but its beaks are more nearly central and more 

vertical (less prosogyrate). It has no lunette or luriule and only a weakly developed ligamen tal groove. It is of Devonian age. . 

Cardiomorpha De Koninck, ~842/ has a large shell, without radial fold or sulcus; smooth 

or with concentric strire; inflated; oviform; beaks depressed, twisted spirally; ligamenta.\ groove 

well developed, but no anterior lunule; obscure indications of an internal ligamenta} furrow. 

Well developed in the middle Carboniferous, less so in the lower and upper Carboniferol:ls; 

one species in uppermost Carboniferous (Permian); Similar shells occur in the Silurian, but 

the Silurian and Devonian forms usually called· Cardiomorpha belong elsewhere. In the 

Bohemia Silurian (eta.ge E) occur some apparently typical forn1s of Cardiomorpha-large, smooth, 

oval shells with n1ore or less strongly and spirally twisted beaks, including Isocardia pollens 

Barrancle, Isocarclia elongata Barrande, Isocardia incumbens Barrande, etc.8 Like typical Cardiomorpha ·these shells have a posterior ligamental groove 9 and no very well defined lunule, 

and from present knowledge of these forms they may be referred to Cardiomorpha. This 

occurrence indicates the appearance of Carboniferous Cardiomorpha as early as the Silurian 

(etage E) of Bohemia, equivalent to the English Wenlock-Aymestry, or to the American 

Guelph. 

Broeckia de IConinck/ 0 1885, resembles Cardiomorpha in its large size, inflated aspect, and 

sn1ooth oval surface, but has· the beaks n1ore depressed and not so strongly or spirally twisted 

as in Cardiomorpha. It occurs in the middle Carboniferous. Some Silurian shells from Bohe-

:inia n.gree with this type in visible features, and a few Devonian species may be referred to it. 

Isoculia :McCoy, 1884, emend. De Koninck, 11 1885, resembles Cardion1orpha in its inflated 

0\7 al expression, but the beak is not at all spirally twisted; the surface is covered with concentric folds, not smooth, and the lunule is well developed in the type species. The typical 

forms are 1niddle Cn,rboniferous, but the genus evidently. extends down to the Middle Devonian 

I Hull, Jmnes,and \Vhitflold, R. P., Fossils of the Hudson River group: Puleontology of Ohio, vol. 2, p. 90, pl. 2, figs. 9, 10, 12. Type c. miamicnsus UullmHl Wllitfield, "Hudson River group" (Upper Ordovician), Waynesville, Ohio. 

2 Ulrich, E. 0., Paleontology of Minnesota, vol. 3, pt 2, p. 620, 1894. · 

8 Compare LC]Jtodomus maincnsis, from Pembroke, Maine (Billings, Elkanah, Portland Soc. Nat. Irist. Proc., vol.1, pt. 2, p.ll8,pl., 1869). The 

shell occurs in u series of gray shulos and volcanic rocks in the Eastport quadrangle, which have been named Pembroke formation. 

4 Soo McCoy, Frederick, 'British Paleozoic fossils, p. 279, pl. lK, figs. 21-24, 1854. 

n Do Koninck, IJ. G., Faune du calcairo carbonifere de Ia Belgique, p. 66, 1885. 

o Paleontology of New York, vol. 5, pt. 1, p. Iii, 1885., 

7 Do Koninck, L. G., Descriptions des a.nimaux fossiles du terruin carbonifere de Ia Belgique, p. 101, 1842; Faune du calcaire carbonifere de· 

Ia Bolglquo, p. 9, 1885. Not Beushausen, L., Die Lamellibranchiaten des rheinischen Devon: K. preuss. geol. Landesanstalt Abh.,new ser., vol. 

17, p. 276, 1895. 

s Barrando, Joacl1im, Syst8me silurien du centre de lu Boh~me, vol. 6, pl. 250, figs. 19-21; pl. 251,1881. 

o Idem, pl. 251, fig. 10. 

1o Do Koninck, L. G., Faune du ca.Ieaire carbonifere de Ia Belgique, p. 19,1885. 

n Idem, p. 17. · 
132 FAUNA OF THE CHAPMAN SANDSTONE OF MAINE. 

if not lower. Grammysia obsoleta I-IalJl seems to be a typical form of Isoculia, and in the same 

group may be included Grammysia arcuata HalP and several other members of "Hall's section 

0. undulata" under Grammysia. 

· Finally, as possibly among the grammysioids may be mentioned Pholadella Hall, 3 1869 

(including Cercomyopsis Sandberger, 1887 = Physetomya ffirich). · 

The term Cercomyopsis might possibly be 'retained for the very finely striated Pholadellas 

called Leptodomus by Beushausen and for such similar American speci.es as Grammysia constricta 

Hall, but the Ordovician Physetomya, 4 founded on P. acuminata Ulrich, from the "middle 

Cincinn~ti beds," appears to be synonymous with Cercomyopsis and the term Cercomyopsis 

is preoccupied for a different Mesozoic shell so called by Meek, so that Ulrich's name, PhysetoIP.ya, may stand for the Devonian shells above included in Cercomyopsis Sandberger. Should 

the posterior margin in Pholadella and in Physetomya (Cercomyopsis) prove to be gaping, 

these shells might have to be affiliated with Cimitaria r·ather than with Gramn1ysia. Some 

species. of Pholadella approach Cimitaria in the elongated posterior portion, which is not, however, nearly so elongated as in normal Cimitaria. Other species approach Grammysia, but 

none have a radial fold or sulcus structure. The margins are closed ( ~). The lunette and 

posterior ligamental groove (external) are well developed~ The distinguishing feature of the 

genus is the presence of more or less well developed radiating strire marking the central part 

of the body from beak to margin, but absent on the anterior portion and posterior slope. Concentric ornamentation is also developed as usual. The Pholadellas are mostly Devonian. 

They are rare in the Carboniferous but range down to the Ordovician. 

Geologi? range of Grammysia.-The genera above discussed include most of the shells erroneously identified with Grammysia.5 Grammysia thus restricted, as it should be, to the closed, 

edentulous or practically edentulous grammysioids having a well-developed lunette and posterior 

ligamenta! groove, and (most particularly) with indications, at least in some part of their life 

history, of the characteristic radial fold and sulcus structure, ranges fro1n the Upper Ordovician 

to the Upper Devonian. 

It seems to be very rare i~ the Ordovician, though Cuneamya is abundant. Beushausen 6 

recognizes forms of Grammysia s. str. from the Ordovician of Russia.. The particular forms 

·referred to are not indicated, but they are probably Grammysia avus Eichwald and G.1nacroderma 

Eichwald/ species also mentioned by Barrande 8 in his note on geologic range of Grammysia. 

Eichwald's paper is not at hand,'so that it can not be stated whether the Russian species named 

are really Grammysia. Barrande's Grammysia? prrecox, from. etage E, is not a grammysioid, 

as has been pointed out by Beushausen. In America typical Grammysia is represented in the 

Upper Ordovician by "Ouneamya" coriformis Miller. 9 A typical Grammysia in the Cornell 

University (Jewett) collection appears to come from the St. Peter sandstone of :Minnesota, but 

unfortunately it is insufficiently labeled. 

In the Silurian Grammysia occurs particularly in the Upper Ludlowian faunas of Russia, 

Sweden, Great Britain, Nova Scotia (Grammysia remota, rustica, and acadica Billings 10), and the 

Eastport or Cobscock Bay region. It is extremely rare in. the Appalachian Helderberg or 

Oriskany. A new species of Grammysia is indicated by Schuchert 11 in his list of the I-Ielderberg 

fauna of New York, but whether this is a Grammysia s. str. is unknown. A new species of 

1 Paleontology of New York, vol. 5, pt. 1, pl. 59, figs. 26, 27, 1885. 

2 Idem, pl. 61, figs. 1-5, etc. · 

a Compare Leptodomus Beushausen (op. cit.), not McCoy. Beushausen has applied McCoy's generic name Leptodomus to some Lower Devonian apparently closed grammysioids of the typical Pholadella aspect superficially. The following, illustrated by Beushausen (op. cit., pl. 24) 

are typical Pholadella: Leptodomus securiformis (Sandberger), L~ acutirostris Sand berger, L. medius Beushausen, nov., L. striatulus (F. Roemer), 

whereas" Leptodomus" latus Krantz, L. posterus Beushausen, nov., and L. barroisi Beushausen, nov., are typical Goniophora (Phillips) Hall. 

4 Ulrich, E. 0., Geology of Ohio, vol. 7, p. 693, pl. 49, figs. 12-14, 1-894. 

s P.-osoccelus Keyserling (Deutsch. geol. Gesell. Zeitschr., vol. 9, 1857; Tripleura Sandberger, 1889), Sphenolium Miller (North American 

geology and paleontology, p. 513, 1889; Ordovician), Sphenotus Hall (Paleontology"of New York, vol. 5, pt. 1, p. xxxiii, 1885; Devonian to Carboniferous), Spa thelia Hall (idem, p. xx.xv; Devonian to Carboniferous), Vlasta Barrande, 1882 'in part), and a few other genera are sometimes confused 

with Grammysia or, more commonly, with some of the gramniysioid genera mentioned above. 

o Beushausen, Louis, op. cit., p. 229. 

1 Lethrea rossica, pt. 7, p. 1015, 1860. 

s Syst~me silurien du centre de la BoMme, vol. 6, p. 87, 1881. 

. o North American geology and paleontology, p. 474, figs. 805,806, 1889. 

10 Pale9zoic fossils, vol. 2, pt. 1, pl. 11, 1874. 

n Geol. Soc. America Bull.; vol. 11, p. 286, 1900. 
MOLLUSCA. 133 

Gram1nysia s. str. is meagerly described by Shimer 1 from the Oriskany of Trilobite Mountain, 

N. Y. The genus is well·represented in the Grande Greve fauna of Gaspe, both Grammysia 

canadensis Billings and Leptodom1.ts canadensis Billings appearing to be true Grammysias. It is 

also abundant in the European Lower Devonian, particularly in the arenaceous deposits. It 

is rare in the A1nerican Lower Devonian but is well. represented in the Middle Devonian and 

the Ithaca shale n1en1ber of the Portage formation of the Upper Devonian, though rare except 

locally in the Upper Devonian in general. In the Cayuta shale member of the Chemung formation of south-central New York calcareo-arenaceous banks have been observed which are a 

mass of shells of a large Grammysia, but in the general body of the Chemung formation Grammysia is exceedingly rare. 

'rhe genus is unknown in the Carboniferqus. All the American Carboniferous "Grammysias" 

listed by Weller 2 are not only without the radial f_old and sulcus or any strictly corresponding 

structure, but n1ost of the species are gaping posteriorly. (See, for instance, "Grammysia" 

hannibalensis as figured by Mille1·, 3 also '' Grammysia '' famelica Herrick. 4 These will have to 

be included in the Leptoclon1us-Sedgwickia-Sanguinolites groups. Sinupalliate and gaping 

shells of the Sanguinolaria and Allorisma groups are confined to the Permian rocks or higher. 

The n1m·ely gaping Leptodomus, Sedgwickia, and Sanguinolites apparently begin with the 

Cu.rboniferous, for no gaping shells of these types are actually known in the lower rocks. Devonian gaping shells like Cimitaria are, of course, easily distinguished from the· grammysioid 

Leptodmnus, Sedgwickia, etc. The genus Rhytimya was founded by E. 0. Ulrich 5 for some 

Ordovician gaping shells the species of which had been previously described. 6 Rhytimya has 

been regarded by Ulrich as closely allied to Pholadella, but its affinities are apparently not with 

the grammysioids but rather with the Ordovieian orthodesmoids. 

Subgenus GRAMMYSIOIDEA subgen. nov. 

The new subgenus Grammysioidea comprises grammysioids differing from Grammysia essentially in the absence of the radial fold and sulcus, from Isoculia in the presence of a posterior 

rounded carination and distinct posterior slope, and from Cuneamya in t,he last-mentioned 

respect, in being larger and· less elongated, and in having beaks less nearly terminal. 

Clqsed edentulous shells of medium to large size, transversely and obliquely ovate to subcircular, not elongate; equiv~ve, inequilateral; beaks fairly prominent, incurved, directed 

forward, and situated i1.1 the anterior half, but not terminal, leaving a distinct anterior portion 

of the shells separated from the beak by a concave lunule. I-Iinge line fairly long but much 

less than the length of the shell, straight or slightly' arcuate, and reclining posteriorly, rarely 

horizontal. Posterior edge retrorse. A well-defined carination extends from the beak to the 

posterior basal angle, producing a distinctly flattened posterior slope. Posterior to the beak 

the cardinal margin is strongly inflected, producing a conspicuous escutcheon for the reception 

of the liga1nent. Anteriorly the lunule is deeply excavated for the ligament. On the interior 

of the hinge there are apparently no teeth. Muscular in1pressions and pallial line as in typical 

Gran1n1ysia, except that the pallial impression has not been ol>served to be radially striate. Surfn.ce covered with concentric strire and more or less irregular concentric folds; son1etimes with 

an obscure, very slight insinuation in the middle, but never, in any stage of development, with 

any pronounced radial fold or sulcus structure corresponding to that of Grammysia. 

The type is Grammysioidea princiana sp. nov. rhe subgenus also includes the species 

listed below, though smne of the Upper Devonian forms may possibly prove to be gaping shells 

and hence distinct. 7 · 

Cypricardites caswelli. Foerste, Denison Univ. Sci. Lab. Bull., vol. l, p. 92, pl. 14, figs. 12a, 12b, 1885. 

Clinton group: Ohio. 

Megalodon curvatus. Krantz, Naturhist. Verein preuss. Rheinliinde Verh., vol. 14, p. 161, pl. 11, fig. 4, 1857. 

Siegen graywacke: Menzenberg. · 

1 New York State :Mus. Bull. 80, pp. 2G1, 2G7, 1905. 

2 U.S. Geol. Survey Bull. 153, 1898. 

a Op. cit., p. 483, fig. 831. 

4 Ohio Goo!. Survey, vol. 7, pl. 17, fig. 5 (Jower·figure), 1893. 

~ Paleontology of :Minnesota, vol. 3, pt. 2, p. G18, 1894. 

6 Ohio Gool. Survey, vol. 7, pp. G88 et seq., 1893. 

7 See Paleontology of New York, vol. 5, pt. 1, pl. 59, figs. G-12; 

pl. 60, 1885. 
134 ·FAUNA OF THE CHAPMAN SANDSTONE OF MAINE. 

I 

A.llorisma plicatella.. Oehlert, Soc. geol. France Mem., 3d ser., vol. 8, p. 34, pl. 6, figs. 3, 3a, 3b, 1881. 

Eo-Devonian: Nehou, Normandy. · 

Grammysia sp. indet. Reed, South African Mus. Annals, vol. 4, pt. 6, p. 252, pl. 31, fig. 3. 

Bokkeveld series: Ezel-fontein, Ceres, Cape Colony. · 

Grammysia lundi. Clarke, Mus. nac. Rio de Janeiro· Arch., vol. 10, pl. 6, figs. 11, 12, 13, 1899 (author's English ed., 

p. 66, 1900). 

Eo-Devonian: Rio Maecuru, Para, Brazil. 

Grammysia ulrichi. Clarke, idem, p. 67 (not pl. 7, fig. 12). 

Meso-Devonian: Erere, Para, Brazil. . 

Grammysia alveata (Conrad) and G. lirata: Hall, Paleontology of New York, vol. 5, pt. 1, pl. 59, figs. 6-12; pl. 60, 1885. 

Hamilton group: New York. 

Leptodomus interplicatus. Clarke, New York State Mus. Mem., 6 (Naples fauna, pt.. 2), p. 315, pl.12, figs. 32-34, 1903. 

Middle Portage: Naples, N. Y . 

. Grammysia minor. Walcott, U.S. Geol. Survey Mon. 8, p. 174, pl. 15, figs. 15, 15a, 1884. 

Upper Devonian limestone: Rescue Hill, west of Rescue Hill, and at gate northwest of Eureka, Nev. 

Grammysia undata. Hall, Paleontology of New York, vol. 5, pt. 1, p. 379, pl. 93, fig. 21, etc., 1885. 

Panama conglomerate. and upper Chemung sandstone: Panama, Portville, and Salamanca, N. Y.; Warren 

County, Pa. 

Grammysia duplicata. Hall, idem, p. 380, pl. 93, fig. 23. 

Chemung group: Warren, Pa. 

Grammysia glabra. Hall, idem, p. 369, pl. 93, fig. 24. 

Chemung group: Warren, Pa. 

As already indicated, these shells suggest the typical large Grammysia but differ in the 

complete absence of the radial fold or sulcus developed in Grammysia. The species of Gram-. 

mysia most nearly approaching Grammysioidea are Grammysia inequalis Beushausen 1 and 

"Leptodomus" canadensis Billings/ especially the former, but in these there is a well-defined 

sulcus, at least in the younger stages of the shell. In some forms of Grammysia triangulata 

Salter, from the late Silurian of the Eastport quadrangle, Maine, one valve is occasionally 

devoid of fold and sulcus, this structure appearing only in the umbonal portion of .the opposite 

valve. 

As to the subgeneric importance of the complete absence· of the radial fold and sulcus 

structure in shells to be dissociated from Grammysia, it may be stated that the presence of the 

radial fold and sulcus was regarded by ;De Verneuil, the founder of the genus, as the distinguishing characteristic of Grammysia. Not only was the genus thus restricted by De V ~rneuil 

himself to shells with this characteristic feature, but subsequent descriptive ·paleontologists 3 

have, with exceptions, 4 used· the term Grammysia in the strict. sense of De Verneuil, the 

founder. Billings does not describe Grammysia· generically, but indicates perfectly by his use 

of the terms Grammysia, Leptodomus, and Sanguinolites that he limit.s the use of Grammysia 

to the strict sense. Beushausen most emphatically restricts Grammysia to the shells having 

the fold and sulcus structure. Hall himself was at first also inclined to the restricted use of 

the tern1 Grammysia, as is indicated by his use of the term "Leptodomus" (in his preliminary 

report, 1883) for several species not strictly Grammysia. 

If Hall's expansion of the genus Grammysia to include as strictly congeneric .. with the 

type species G. · bisulcata (Conrad) such shells as G. globosa Hall and G. obsoleta Hall, 

which have no indication. whatever of radial fold and sulcus, is to be accepted, it will be necessary to expunge the genus Grammysi~ from the literature altogether for the globosa and obsoleta 

types are congeneric with Isoculia McCoy, ·which has several years' priority over Grammysia. 

Grammysia would then be merely a synonym of .Isoculia. Even a very slight study, however, 

would show the unreasonableness of adopting the conclusion just indicated; but it must be 

emphasized that if the term Grammysia is to be used at all, it must be restricted to shells having 

the characteristic radial fold and sulcus in at least some stage of develop1nent. Shells com1 Beushausen, Louis, Die Lamellibranchiaten des rheinischen Devon: K. preuss. geol. Landesanstalt Abh., new ser., vol: 17, pl. 21, figs. la, 

lb, 1895; Sicgen graywacke. 

2 Billings, Elkanah, Paleozoic fossils of Canada, vol. 2, pt. 1, p. 54, pl. 5, fig. 1; Gaspe limestone No. 8 (Oriskanian), Indian Cove, G.aspe, 

Quebec. 

a McCoy, Frederick, British Paleozoic rocks and fossils, pp. 280 et seq., 1885. Billings, Elkanah, Paleozoic fossils of Canada, p. 51, etc., 1874. 

Lindstrom, G., in Angelin, N. P., Fragmentasilurlca, p. 20, 1880. 

4 Hall, James, Paleontology of New ~ork, vol. 5, pt. 1, p. 1885. 
0 

MOLLUSCA. 135. 

pletcly lacking all traces of such radial fold or sulcus c&n not, therefore, be inclq.ded in Grammysia, so that we are quite justified in erecting the subgenus Grammysioidea for the species 

indicated. As a matter of fact, some paleontologists may prefer to consider Grammysioidea as 

worthy of full generic rank. Grf:Lmmysioidea is intermediate between Grammysia and 

Cunea1uya, having the size and pr.oportions of the former but being, like the latter, without 

radial sulcus. It is also intermediate between Isoculia and Grammysia, lacking radial sulcu.s, 

like the ~ormer, and having the less evenly rounded or less globular aspect of the latter. 

GRAMMYSIA ACADIOA Billings, var. 

Plate XXIV, figure 12. 

cf. 1874. Grammysia acadica. Billings, Paleozoic fossils of Canada, vol. 2, p. 140, pl. 9, figs. 4, 4a. 

Upper Arisaig series [with Upper Ludlow fauna]: Arisaig, Nova Scotia. · 

1909. Gramn.,ysia acadica. Twenhofel, Am .. Jour. Sci., ·4th ser., vol. 28, pp. 155-158. 

l\foydart and Stonehouse formations [Aymestrian and Upper Ludlow faunas]: Arisaig, Nova Scotia. 

A single poorly preserved internal mold of a left valve, the only specimen of Grammysia 

in tho Chapman fauna collections, is characterized by having the radial sulcus unaccompanied 

by any fold and reaching the basal margin posterior to the middle (at the posterior fourth or 

fifth). The length is a trifle. less than twice the height; cardinal and basal margins subparallel; 

posterior n1argin retrorse, with the n1ost posterior point near the midheight. Greatest height 

well in front of the middle, son1owhere near the anterior two-fifths; greatest length only. slightly 

.below the midhe!ght; height 24 1nillin1eters, length 45 millimeters. Umbones broad, incurved, 

directed forward; beaks at t.he anterior sixth. Cardinal line parallel to the.longitudinal axis; 

very gently convex, a little greater than the height of the shell, the highest poi.rlt being back of 

tho beak at about the anterior third or two-fifths. Cardinal extremity angular, obtus~; post<:n·ior 1nargin in the upper h:ttlf retrorse, straight, or hardly appreciably convex; lower half of 

tho posterior 1nargin rounding into the basal margin. At the posterior end the basal margin 

is slightly insinuated by the radial sulcus, immediately back of which begins the curve of the 

posterior-basal margin. Anterior to the sulcus the basal margin has not been observed, but 

to judge frmu the direction of the very faint lines of growth it app~ars to have been convexstrongly so just in front of the sulcus-rising upward and forward in the anterior portion and 

rounding into the anterior end, which is distinct. The most protruding point of the anterior 

extron1ity is near the midheight. The lunule, which occupies the upper third or fourth of 

tho height, is very distinct, hut the specimen is .too poor to show the lunette. The point of 

greatest depth of the valve is on the rounded umbonal "ridge" back of the radial sulcus, near 

(co1nmonly slightly above) the roidheight and ·at the posterior third of the length of the shell. 

The depth of the valve is 6 millimeters, or one-fourth the height .. Except for the concave 

radial sulcus the surface Is rounded throughout. The umbonal ridge is broadly rounded, forming 

part- of the general convexity of the s;hell. The slope is very steep and convex to the cardinal 

line, less steep over the anterior portion in front of and below the umbo, and still less steep over 

tho general surface. In fact, between the convex anterior end and the convex posterior slope, 

tho general surface over the central regions is depressed convex or almost flat. The radial 

sulcus is slightly concave, very shallow, and hardly discernible on the internal mold, unless 

oriented at the proper angle to the light; it is extremely faint over the umbones, but expands 

slightly and becon1es more pro.minent lower in the mold. It forms an angle of about 45° with 

tho cardinal line and terminates .on the basal margin at about one~third or one-fourth of the 

length in front of the posterior extren1ity. There are no radial folds. 

1'ho surface ornamentation consists of obsolescent growth lines with irregular obsolescent 

concentric wrinkles·; the ornan1entation is more pronounced on the posterior slope, but is very 

obscure on the specin1en at hand. 

Length 45 1nillimeters, height 23.5 or 24 millimeters, depth of the valve nearly 6 millimeters. 

Locality: Chapman sandstone, Edn1unds I·Iill, Chapman Township, Aroostook County, Maine. 

U. S. National Museum, cntalogue No. 59760. 
136 FA UN A OF THE CHAPMAN SANDSTONE OF MAINE. 

Oomparisons.-In the transverse <1utline and radial sulcus· reaching nearly to the posterior 

instead of anterior or central basal margin, this Grammysia resembles G. ovata (Sandberger) 

from the lowest or Singhofen Coblenzian; but Grammysia ovata and most of the Devonian Grainmysias have a radial fold and sulous on each side, whereas in the present.form there is no radial 

fold and only one radial sulcus. 

The Devonian Grammysias 1 with only one radial sulcus have the base of the sulcus rarely 

at and generally in front of the middle, never near the posterior extremity, as in the present form. 

Grammysias having only a single well-defined sulcus reaching nearly to the posterior basal margin, as in the type at hand, have been confined, so far as hitherto .known, to pre-Devonian rocks, 

in which occur a few forms that are very closely related to G. acadica var., namely, Grammysia 

cingulata (not Risinger) (Salter), 2 in part, from the tilestones of Llangadoc, in the Usk region; 

and Grammysia acadica Billings,3 from the upper faunas of Arisaig, Nova Scotia. These two 

forms may be the same species. Grammysia exarata Lindstrom/ from the late Silurian oolite at 

Bursvik,.Gotland, is also similar. The Chapman shell differs from both G. acadica and Salter's 

form in two respects. First, in the present specimen the umbones are less nearly terminal, 

being one-sixth the length frmn the anterior margin, and there is consequently a more pronounced anterior portion of the shell; second, in both the European and Acadian fossils there 

is a second more or less definite concave depression in front of the radial sulcus, but no trace of 

·such a depression is present in the specimen at hand, whose surface is convex throughout except 

for the radial sulcus. Because of the differences indicated I refrain fro1n identifying the Chapman shell with the late Silurian Grammysia acadica Billings (or with Salter's "Orthonota" cingulata 

(not Risinger), 1'848, which is presumably cospecific with Billings's species) with any greater 

degree of definiteness than to call it G. acadica var. 

GRAMMYSIA (GRAM:MYSIOIDEA) PRINCIANA sp. and subgen. nov. 

Plate XX, figure 8. 

Shell large, closed, equivalve, very inequilateral, transversely and obliquely subovate. 

(The particular specimen figured is inequivalve, but this is due to posthumous crushing in the 

rock during fossilization:) Greatest height one-third the length fron1 the front; height about 

eleven-twentieths of the length; greatest length two-fifths the height from the base. Beaks 

incurved, directed forward, situated one-fifth the length from the anterior extremity. Hinge line 

posterior to the beak, equal in length to the height of the shell, straight or nearly so, and declining 

so that the posterior extremity of the hinge is one-fourth or one-fifth the height below the 

beaks. Postero-cardinal region angular, obtuse; posterior margin retrorse, straight, or very 

slightly convex from cardinal extremity to point of maximum length, which includes a distance 

. equal to about thr~e-fifths the length of the cardinal line. Postero-basal region rounded-angular, 

the posterior margin and posterior basal margin forming an angle of about 95°. Basal margin 

nearly straight to the point at the base of the maximum height, whence it arches upward to 

the anterior extremity. The anterior portion of the shell is unsymmetrically rounded, the 

upper portion having a shorter radius of curvature than the lower. At n1idheight the anterior 

extremity is abruptly recurved, producing a long, concave lunule in front of the beaks. Depth of 

both valves in conjunction probably about half the height. The specimen as preserved is crushed 

and flattened and only 20 millimeters thick, but it seems originally to have had a thickness of 

26 or 28 millimeters and a height of 55 millimeters. The thickness is therefore certainly not 

less than one-third nor more than one-half the height. Point of greatest convexity on the line 

of maximum height; about a third below the cardinal line; the shell is equally deep on the 

posterior carination three-sevenths of the distance from the umbones. The umbo is convex 

but not tumid; incurved; the beaks almost on the hinge line. The general surface of the shell 

I Compare G. abbreviata Sandberger, G. prumiensis Beushausen, G. inxqualis Beushausen, G. taunica (Kayser), and G. obscura Beushausen 

(Beushausen, Louis, Die Lamellibranchiaten des rheinisch.en Devon: K. preuss. geol. Landesanstalt Abb., new ser., vol. 17, pp. 243-249, pls. 

19-22, pars, 1895), which range from lower to highest Eo-Devonian. 

2 Phillips, John, and Salter,·J. W., The Malvern Hills: Geol. Survey Great Britain Mem., vol. 2, pt. 1, p. 360, pl. 17, fig. 2 (cet. excl.), 1848. 

a Paleozoic fossils of Canada, vol. 2, pt. 1, p. 140, pl. 9, figs. 4, 4a, 1874. 

4 Angelin, N. P., Fragmenta silurica, p. 20, pl. 19, fig. 33, 1880. 
MOLLUSCA. 137 

is very gently convex, except for a rounded carination extending from the beak to the posterobasn.l angle, on which .the convexity is more pronounced~ Posterior to this carination the surface is flat or very slightly, :almost imperceptibly, concave to the cardinal line. The general 

surface over the greater part' of the shell anterior to the carination is depressed-convex or almost 

flat, except the· anterior end, which is more distinctly convex. In front of the beak there is a 

concave lunette. Posterior to the beak the cardinal line is abruptly inflected to form a large, 

deep ligmnental groove. 

The surface is covered with very low concentric folds which are fairly even and regular 

on the umbones but become irregular and obsolescent over the general area of the shell, producing a concentrically striate, faintly undulose surface. There is no indication of any radial 

fold or sinus comparable with the cincture in the Grammysia, nor is there any abrupt insinuation 

or interruption of the continuity of the concentric markings. There is, however, an extremely 

faint undefmed sinus which c.auses the flattening of the general central surface and also produces a very feeble, scnJ'cely perceptible long constriction of the basal margin. Posterior to 

the carinu.tion the strire are recurved parallel with the ma:r;gin, the carination serving as the angle. 

The lunette is sn1ooth, concave, equal in length to more than one-third the height of the shell, 

n.nd very wide. 

Except for the presence of a long, deep posterior ligamenta! groove and a conspicuous 

anterior lunule and well-developed lunette the hinge features are unknown. The n1uscular 

scars are distinctly developed. The· anterior adductor is oval or semicircular, situated just 

under the anterior half of the lunule. The posterior adductor scar is suboval or obtusely triangular, about twice as long a~. the anterior scar; it is situated on and just in front of the posterior carination but does not extend back of it. There are no discernible pedal, retractor, or other 

accessory muscular scars. The pallial line reaches the anterior third or half of the posterior scar, 

thus len.ving the posterior half or two-thirds of the scar outside. The posterior portion of the pallial impression has not been very clearly preserved, but ~t appears to be simple (noninsinuated) and, 

as in Grammysia, 1 extends frmn the posterior scar backward and downward, then curving forward, nem·ly straight and parallel with the basal margin, then reaches upward and forward 

to the anterior scar, near the forward basal extren1ity of which the pallial line ends. No radial 

striations or pits have been observed along the pallial impression, which is, indeed, very obscure 

in the specimen at hand, but whether this absence· is due to imperfect preservation of the present 

specimen or to the real tenuity of the pallial impression can not be stated. 

As already indicated, the specimen is 100 1nillin1eters long, 55 n1illimeters high, and, as 

restored fr01n its crushed condition, between 26 and 28 millimeters thick. These dimensions 

indicate the large size of the species. 

Locality.-~1.oose River sandstone, Detroit, Maine. 

Oomparisons.-This species resembles very closely Grammysia C(tnaclensis Billings,2 from 

the lower part of the Gaspe stmdstone at Gaspe, but G. canadensis has a rather longer and 

less declining hinge line, a slightly n1ore nasute postbasal extren1ity, a n1ore arcuate basal line, 

and, n1ost in1portant of all, has a distinct fold and two sulci in the left valve and corresponding structures in the right valve. In Gntm1nysioiclea princiana there is of course no indication 

whatever of fold or sulcus. 

Another ren1n.rkn.bly close ally of Grammysioiclea princiana is Grammysia inmqualis 

Beushausen, 3 fr01n the Siegei1 graywacke of Y sen berg, a species which has no appreciable 

indication of the radial fold i.Jrr the right valve, and only obscure trn.ces of a radial sulcus, 

accentun.ted by an abrupt interruption of the ornamentation, ·in the left valve. · The differences between these two species are very slight; they include a more pronounced posterior 

• Soo Do Vornouil,Edouard, Soc. gool. France. Bttil., 2d ser., vol. 4, p. 697, fig. 2, 1847 (G. "hamiltonensis," from Nebou, Normandy); also Hall, 

James, Paleontology of New York,·vol. 5, pt. I, pl. 54, fig. 8 (G. bisulcata), pl. 57, figs. 3-4, 1885 (G. circularis), both species from thellamilton of 

Now York. Soo also Beushnusen, Louis, Die Lamellibranchiaten des rheinischen Devon: K. preuss. geol. Landesn.nstalt Abh., new ser., vol. 17, 

pl. 23, fig. I, 1895 (G. marginata Goldfuss, from the upper Eo-Devonian of Lahnstein, in the Rhenish province). 

2 Billings, Elkannh, Paleozoic fossils of'Cnnadn, vol. 2, pt. 1, p. 51, pl. 4, fig. 3, 1874 (not Leptodomus canadensis Billings, idem, p. '54, pl. 5, fig. 1, 

which is also apparently a Grnmmysia). 

snoushnuson, Louis, op. cit., p. 245, pl. 21, figs. In, lb. 
138 FAUNA OF THE CHAPMAN SANDSTONE OF MAINE. 

carination, more retrorse posterior margin, larger posterior slope, and weaker concentric ornamentation in the American species. The left valve is too poorly preserved in G. princiana for 

comparisons with reference to the radial sulcus structure, but in the right valve of the specimen 

at hand there is no trace whatever of such structure. · 

Perhaps the closest resemblance is to Megalodon (Grammysioidea) curvatus Krantz/ in which 

the beak is more anterior and the ornamentation more obsolescent. Beushausen regards this 

species as possibly cospecific with his Grammysia incequalis . 

. Grammysioidea alveata (Conrad), G. lirata (Hall), and G. interplicatus (Clarke) are easily 

distinguished from G. princiana by their n1ore nearly circular or less transverse. outline, comparatively shorter hinge, and stronger 1narkings. · 

GRAMMYSIA (~ GRAMMYSIOIDEA) MODIOMORPHlE (Clarke). 

Plate XXIII, figures 16, 17. 

1907. Grammysia modiomorphre. Clarke, New York State Mus. Bull. 107, p. 221, two lower :figures (not upper :figure). 

Lower Devonic [Chapman sandstone]: Edmunds Hill, Chapman Township, Aroostook County, Maine. 

A large species of Grammysia which seems to be very common in the Chapman sandstone of Edmunds Hill (locality 1099 C) is represented in the collections by about half a dozen 

poorly preserved specimens. In this species the length is less than twice the height, the ratio 

of length to height varying from 12:7 to 3:2. The greatest height is slightly in advance of the 

midlength. The umbones are broad, incurved, directed forward; the beaks are at the anterior 

:fifth. The cq,rdinal line is nearly straight, very slightly reclining, and equal in length to the 

height of the shell. The posterior margin is retrorse, the upper part nearly straight, the most 

projecting point at the lower fourth or third.· The basal margin is straight or broadly insin-

. uated for a distance about equal to the length of the cardinal line, whence the basal margin 

rises forward and upward in a broad curve which rounds off into the anterior margin. The 

anterior portion of the shell is very distinct, with the most projecting point near or slightly 

below the midheight. The lU.Uule is well defined. and begins at about the upper third of the 

height. With regard to convexity, the distinguishing feature is a broad, persistent sinus over 

the central part of the shell becoming more pronounced toward the base, where it produces a 

more or less distinct c.oncavity of the surface and broad constriction of the margin. The 

umbonal ridge is broadly rounded, undefined. . 

The surface ornamentation consists of concentric obsolescent growth lines irregularly aggregated into concentric obsoles~ent ridges or undulations. Three specimens have, respectively, 

the following dimensions: Length (in millimeters), 61, 68, 57; height (in millimeters), 36, 40, 33. 

Locality . ...;_Chapman sandstone, Edmunds Hill, Chapman Township, Aroostook County, 

Maine. 

U. S. National Museum, catalogue No. 59761. 

Oomparisons.-The species is very closely allied to G. princiana, from which it differs in 

the conspicuous broad sinus, the proportionally somewhat greater height, and in the smaller 

siz;e. There is also a close relationship with Orthonotus semisulcatus McCoy 2 (not Sowerby) 

from the .Upper Ludlow green quartzite of Kirkby Moor, near Kendal, Westmoreland, in the 

general expression produced by the similar outline and convexity and the broad sinus, but the 

. English shell is smaller, the beaks slightly more anterior, and the posterior ~argin less straight. 

GRAMMYSIOIDEA ELYMELLOIDES sp. nov. 

Plate XXIV, :figure 10. 

Transversely ovoid, widest in front; length twice the height; maximum length at the mid-

. height; greatest height at the anterior third, back of· the beak .. The dimensions of the two 

• Krantz, A., :Ueber ein neues bei :Menzenberg aufgeschlossenes Petrefakten Lager in den devonischen schichten (Siegen graywacke): N aturhist. 

Ver. preuss. Rheinliinde Verh., vol. 14, p. 161, pl. 11, figs. 4a,.4b, 1857. · 

2 McCoy, Frederick, British Paleozoic rocks and fossils, p. 275, pl. 1 K, fig. 25, 1855. The Modiola(?) semisulcata Sowerby (Silurian system, 

pl. 8, fig. 6) with which :McCoy considered his shells identical is very distinct specifically, and apparently also generically. 

. \ 
MOL~USCA. 139 

speci1nens are 46 by 24.5 millimeters (type) and 37 by 16 millimeters. Both specimens al'e 

s01newhat crushed; the second is incomplete ventrally. Umbones broad, incurved, arching 

only slightly beyond the hinge line; prosogyrate, beaks at the anterior seventh. I-Iinge line 

long, fro1n 1-g. to It tirrtes the heig4t of the shell; nearly straight, very slightly convex, descending so that the postcardinal extrmnity is one-eighth the height below the umbones. Postcardinal region obtusely rounded. Posterior 1nargin very gibbously arched, convex throughout, 

very retro1·se in the upper third; posterior extrmnity at the n1idheight; lower portion curving 

into the ventral Inargin. Ventral margin convex throughout, strongly bellied down, nowhere 

insinuated or constricted; the extreme lowest point is at the anterior two-fifths, whence the 

ventral nutrgin ascends only very slightly posteriorly bu.t rises very strongly anteriorly into 

the well-developed, rounded, distinct anterior end, ,V.hich includes one-eighth the length of the 

shell and two-thirds the height, and which is separated fro_n1 the umbones by a strong, welldeveloped lunule. A.nterior extremity at the midheight. Rather gibbous, especially over the 

region of the umbonal ridge:, which is rounded and undefined, except by the retral curve of 

the ornan1entation. The posterior slope is convex throughout, as is the entire shell, including the infraumbonal region, which is nowhere insinuated. The umbones are gibbous, inflated, 

incurved, not elevated. The greatest depth of the v·alve is in the region of the rounded umbonal 

ridge, a trifle above the midheight and ·three-fifths the length from the front. The depth of 

the single valve is equal to one-third its height or. a trifle less, though the specimens are 

crushed and the original depth may have been half the height. 

A long, well-developed inflec.tion of the cardinal line produces a very pronounced and 

conspicuous escutcheon. The lunule and lunette are also very well developed. There do not 

appear to be any posterior lateral teeth; the strongly incurved beak prevented any observations as to the presence of cardinal teeth. The anterior muscular scar is broadly oval, situated 

below the lunule, rather faintly impressed. What seems to be a posterior muscular scar is very 

faintly discernible, subcircular, twice as long as the anterior scar; it fills the space between the 

u.mbonal ridge and hinge line and is separate,d by twice its length from the beak. Pallial line 

simple, distant from the ventral margin. Beginning at the base of the anterior adductor scar, 

it curves strongly downward :and backward, is nearly horizontal over the middle of the shelf, 

and ascends very slightly to the umbonal ridge. At the respiratory angle it is abruptly deflected 

forward and upward, making nn angle of less than 45° with the horizontal axis and terminating 

at the inner third of the posterior adductor scar, leaving most of the posterior muscular scar 

outside of and a'!:>ove the pallial line.· , 

There are no discernible 1mdulations; the surface is smooth, marked only by obsolescent 

faint tenuistriate lines of growth. The internal mold is smooth and devoid of ornamentation. 

The distinguishing features of the fossil are the transversely ovoid outline, wider in front; 

sn1all size; rounded, nonconst:ricted basal margin; long .tapering and rounded posterior end; 

s1nooth surface; and absence of ventral insinuation or restriction. 

Locality: Chapman sandstone; both specimens from Presque Isle Stream, Chapman Township, Aroostook County, Maine. 

U. S. National Museum, catalogue No. 59762. 

Oomparisons.-The species is nearly related to Grammysia undata Hall,t of the New York 

highest Devonian (Panama conglomerate), but is quite distinct, lacking the ventral constriction, having the umbones n1ore anterior and being somewhat less strongly marked. Grammysia 

glabra I-Iall 2 is also similar, bu1i has a ventral sinus and more protuberant umbo~es. 

G-enus PHYSETOMYA Uhich, 1893. 

The generic name Physetomya Ulrich has been discussed on page 132, where its relations 

to Cercomyopsis Sand berger, Pholadella Hall, and Grammysia De Verneuil have been indicated. 

1 l)uloontology of New York, vol. 5, pt. I, 1885, p. 379, pl. 61, fig. 23; pl. 64, fig. 30; pl. 93, fig. 21. If Hall's species is u closed, nongaping, shell 

'ft uppurently belongs to the subgenus Gra1nmysioidca. 

2 Idem, p. 369, pl. 93, fig. 24; Chemung grou:p, Warren Colll,lty, Pa. 
140 FAUNA OF THE CHAPMAN SANDSTONE OF MAINE. 

PHYSETOMYA sp. indet. 

Plate XXVI, figure 4. 

This specimen of a left valve is incomplete on the anterior, but indicates a Grammysialike shell of the usual transverse outline common to the species of Cercomyopsis Sandberger 

(=Physetomya Ulrich). On the external mold there were observed traces of fine, continuous 

radial strire below and just back of the beaks and crossing the concentric undulations. The 

body of the shell is covered with coarse concentric wrinkles, which fade out on the posterior 

slope. The imperfection of the specimen anteriorly makes comparisons with allied species 

unfeasible. The portion of the shell preserved recalls· in outline and ornamentation (on the 

internal mold) the British Upper Ludlow Leptodomus truncatus McCoy/ which is a Sphenomya. 

Locality: Chapman sandstone, west side of .Edmunds Hill, Chapman Township, Aroostook 

County, Maine. · 

U.S. National Museum, catalogue No. 59763. 

Genus ELYMELLA Hall. 

The genus Elymella was founded by Hall for some small ventricose Middle Devonian shells 

of uncertain hinge characters, but easily recognizable by their external aspect, which is characterized by strong convexity; transversely elliptical-ovoid outline without insinuation; incurved 

beaks anterior and directed forward, and cardinal line fairly long, convex, and slightly reclining 

posteriorly; both anterior and posterior extremities rounded (as is, indeed, the .entire shell) 

and the short anterior extremity narrower dorso-ventrally than the posterior extremity. The 

ornamentation consists of concentric lines of growth, sometimes elevated into uneven concentric ridges. 

Hall's original 4iagnosis 2 of the genus is as follows: 

Elymella n. gen. (Type, Elymella nuculoides Hall.) Shell equivalve, inequilateral, oyate elliptical. Anterior 

end very short and the margin rounded. Posterior end narrower 3 and rounded at the extremity. Beaks closely 

incurved; umbo prominent. Cardinal line short. Umbonal slope prominent in the upper part, not confined, and 

merging into the general conveocity of the shell. Surface marked by fine concentric strire of growth, which are sometimes lamellose and elevated into concentric ridges. Hinge line short, the internal characters undetermined. Muscular impressions unknown. The small group of shells here termed Elymella can not with propriety be referred to any 

established genus, and therefore this name has been chosen in reference to the form and expression of the fossils. The 

form of the shell and the direction and character of the concentric strire resemble some species of N ucula; but although 

occurring with specimens of the latter genus, showing the· hinge teeth, none of the specimens of Elymella have preserved any indications of such characters. 

Examples: Elymellafabalis, Plate XL, figures 5, 9; Elymella nuculoides, Plate XL, figures 6, 7, 8. 

As to the hinge, it may be safely stated that these shells are edentulous, for no indications of teeth have ever been observed. 

Allied genera.-Figures of species of Elymella resemble very much forms of Glossites, as 

- can be seen by comparing the respective species of the two genera figured on Hall's Plate XL . 

. Glossites is, however, a flattened lamellibranch; Elymella is gibbous. 

Elymella is closely related to the Upper Devonian and Mississippian Spathella lJall, 4 but 

Spathella is somewhat more elongated than Elymella and widens posteriorly instead of narrowing. Elymella is also very closely allied to the gigantic Carboniferous Broeckia De Koninck, 5 

from which it differs practically only in being smaller. Broeckia may occur in the Silurian 

(etage E2 ) of Bohemia. (Compare ·Astarte primula Barrande and the gigantic Isocardia? 

latissima Barrande, 6 which appear to be typical Broeckias.) The genus is un~own in the 

1 McCoy, Frederick, in Sedgwick, Adam, and McCoy, Frederick, British Paleozoic rocks and fossils, p. 279, pl. 1 K, figs. 21-24, 1854. The 

species is from the Upper Ludlow quartzites of Westmoreland. 

2 Hall, James, Paleontology of New York, vol. 5, pt. 1 (Lamellibranchiat::t II), p. 1,1885. , 

sHall's wording is ambiguous here, and might, by one not acquainted with the shells, be taken to mean that the posterior end is narrower 

than the anterior end. This is distinctly not the case. Hall evidently meant that the posterior portion is narrower at the extremity than farther 

forward. · 

4 Op. cit., p. xxxiii, pl. 66, figs. 30-42. 

~De Koninck, L. G., Fauna du calcaire carbonifere de la Belgique, pt. 5, Lamellibranches: Mus. roy. hist. nat. Belgique Annales, vol. 11, 

p. 19, 1885. 

o Barrande, Joachim, Syst~me silurien du centre de la Boh~e, vol. 6, pl. 190, 1881. 
MOLLUSCA. 141 

Devonian. It should be borne in n1ind, however, that the large typical Broeckias occur in limestone lan1ellibranch faunas, whereas in the Devonian lamellibranch faunas- are confined to 

arenaceous and shaly deposits. Typical Broeckia, besides being of relatively gigantic size, 

also differs fro1n :Ely1nella in having the anterior end wider dorso-ventrally than the posterior 

end (for instn,nce, B. p1'isca :McCoy and B. latissima De Koninck 1 (not Barrande); also B. 

'lnutica 2 ), while in Elymella the reverse is of course always the case. However, a few forms of 

Broeck.ia, such as B. subeq_ualis De Koninck,S have the anterior end narrower, as in Elymella. 

When th<;} ;minute lmown Devonian :Elymellas, wl~ose length does not exceed 3 centimeters, 

are compared with the relatively gigantic Carboniferous Broeckias, which commonly attain 

a length of 9, 10, or even 12 centimeters, very little genetic connection. or relationship be~ween 

the two is at f1rst apparent. But in the Belgian Carboniferous occur several Elymellas somewhat larger than the 'Devonian types, and between these Belgian Carboniferous Elymellas 

and typical Broeckia are several transitional forms. The minute De.vonian Elymella and the 

typically gigantic Sihu·ian and Carboni1ferous Broeckia are therefore connected in the Belgian 

Carboniferous by intermediate types, and it seems possible that Elymella is only a minute 

Silurian-Devonian representative of the Silurian-Carboniferous Broeckia which has become 

ad11pted to conditions adverse to the typical development of the gigantic forms. This hypothesis 

is borne out by the thin shell of Elyn1eUa and seems to n,:fford the best explanation of the occurrence of large typical Broeckia in the Carboniferous and ~Silurian, its absence in the Devonian, 

the substantial identity in structural features of Broeckia and the small Devonian Elymella, 

and the occurrence of both types and intermediate forms in the Belgian Carboniferous. 

These Belgian Carboniferous Ely,melias and· tran$itio:ual Elyn1ella-Broeckia forms have 

been doubtfully referred by De Koninck to Edmondia, a genus that has becon1e well ]mown 

tlu·ough its characteristic superficial strongly convex, smooth, quadrate, oval expression, on 

the basis of which ''arious Silurian and Devonian fossils have been referred to it. The essential 

feattu·e of the genus is, however, the presence of ·an internal septun1 underneath the cardinal 

line for the reception of .an internal ( ~) ligament. De Koninck divided the 67 Belgian Carboniferous species of Edmondia into two groups, one group characterized by the globular or orbicular 

expression with lengths approxin1ately equal to the height, and the other group transversely 

elongated. The species with the diB•gnostic internal ligamenta} septun1 are almost entirely 

con:fined to the fu·st group; the elongated species of the second group, lacking this internal 

ligtunontal septu1n, were only doubtfully referred to Edmondia by De Koninck. The genus 

PseudedJnondia Fischer, 1887, is founded on some of De Koninck's Edmondias that lack the 

intor.nnl septun1 and have an a.pparently externalligam~nt, but the species of Pseudedmondia 

are globular shells representing the :fll;st group of De Koninck. The true classification of 

De Koninck's second group of Edn1ondias is therefore stili uncertain, but many of the species 

can be placed under Broeckia, Ely,mella, and probably Isoculia. Among the species that 

can be referred to Broeckia and Elymella are Edmondia? pulchella De Koninck 4 (a very typical.Elymella), Edmondia amydalina -De Koninck, 5 Edmondia? debilis De Koninck, 6 Edmondia? 

elliptica De Koninck/ and Edmondia;? prrelonga De Koninck,8 all of which are referable to the 

genus Elymella, as is also De Koninck's Broeckia dorsata,O the only small form admitted by 

De Koninck into Broeckia; and Edmondia grrelata De Koninck, Edmondia? nobilis De Koninck 10 

(a typicnl Broeckia), Edmondia? decorata De Koninck, 11 Edmondia? p1·recox De Koninck, 12 which 

ht:tve the Broeckia aspect but are tra.nsitional in size from the typical large Broeckia to the small 

Elymella. · 

There is, then, a n1uch closer rt~lationship between Elymella and Bro~ckia than is at first 

sight apparent. It Jnust be remembered, however, that little is known of the hinge structure 

of these fossils. The tenn Elymella has been applied only to the smaller broeckioids having 

1 Do Koninck, L. G., op. cit., pl. 2, figs. 13, 14. 

2 Idem, pl. 3, fig. 18, etc. 

s Idem, pl. 3, fig. 19, etc. 

4 Idom, pl. 10, figs. 21, 22. 

6 Idoni, pl. 13, figs. 30, 31. 

a Idom, pl. 7, figs. 17, 18. 

r Idem, pl. 7, figs. 19, 20. 

s Idem, pl. 7, figs. 21, 

9 Idem, pl. 6, figs. 11, 12. 

10 Idem, pl. 10, figs. 33, 34. 

11 Idem, pl. 10, figs. 31, 32. 

12 Idem, pl. 10, fi~s. 15-20. 
142 FAUNA OF THE CHAPMAN SANDSTONE OF MAINE. 

the anterior end narrower dorso-ventrally than the posterior end. As thus defined Elymella 

is a valid group of characteristic expression. 

Geologic range of Elymella.-Hall 1 described two species of Elymella (E. nuculoides and 

E. jabalis Hall) from the calcareous shales of the Hamilton (Middle Devonian of central and 

western New York, and a slightly larger species (E. patula) from the Mississippian shales, at 

Medina, Ohio. Miller and Gurley 2 have described Elymella missouriensis, from the Chouteau 

limestone (Mississippian) near Se<!lalia, Mo. The Belgian Carboniferous Elymellas already 

mentioned are from etages I and II. No forms of Elymella have been recognized in the etage 

III or Visean Carboniferous. Elymella thus ranges through the lower part of the Mississippian 

Gower Carboniferous), Upper and Middle Devonian, and apparently Lower Devonian. The 

species from the Chapman fauna described below is therefore the oldest Elymella known. 

ELYMELLA HARRIS! sp. nov. 

Plate XXIV, figure 11. 

Shells small, v'entricose; closed, equivalve; transversely elliptical; n1argin rounded throughout, not sinuated. Maximum height at the midlength; maximun1 length at or just below 

the midheight; length twice the height. Umbones small, riarrow, incurved, directed forward at 

a very acute angle with the transverse axis of the shell. Beaks about one-seventh the length 

from the anterior extremity. Cardinal line evenly convex throughout, horizontally or ne.arly 

so as far as a point two-thirds the length of the shell from the front, thence rounding off into 

the !'ymmetrical, semielliptical, or parabolic posterior end. (Parabolic is here used in the s'ense 

opposed to catenaric, to apply to·a curve more ventricose than a circular arc; the term catenaric 

is applied to a curve flatter than a circular arc.) There is no discernible demarcation between 

the cardinal and posterior margins above nor between the posterior and basal nlargins below. 

The posterior extremity is at the midheight. The basal margin is a convex, evenly rounded 

curve of slightly deeper conv~xity than the dorsal line. ·The basal extremity is opposite the 

midlength; the anterior basal line rises more rapidly than the posterior, and merges into the 

small but distinct symmetrically rounded anterior portion of the shell, which includes oneeighth or one-tenth of the length. The depth of the single valve is three-thirteenths of the 

height. The point of maximum depth of the valve is on the rounded umbonal "ridge" opposite 

the midlength of the shell and one-third the height below the ·cardinal line. The surface is 

evenly rounded throughout except for the umbo, which is marked by a short carinate ridge from 

which the surface slope is almost perpendicular to the cardinal line. The nearly perpendicular 

postumbonal slope and umbonal ridge are very short, oextending only to a point one-third or 

two.:.fifth.s the length of the shell from the anterior extremity, beyond which the surface slopes 

in a descent evenly convex in all directions, with only a faint indication of concavity in the 

longitudinal profile just in front of and u·nder the beak. 

The surface ornamentation consists of unequal, obsolescent, concentric lines of growth, an 

occasional stronger line becoming almost lamellose. There are no ridges or plications. The 

strire have the same uniformly convex elliptical curve as the margin. In the specimen figured 

the ornamentation is strongest in the posterior portions of the shell and faintest in the anterior 

end. 

In the single specimen at hand, an internal mold of the left valve, there ~reno indications 

of the existence of any teeth or ligamenta! structures, nor are the~e discernible muscular impressions. There are faint markings comparable with an anterior muscular scar, which, if really 

such, is obliquely ovoid, 4 millimeters long and horizontally striate on the posterior or narrower 

end. From the anterior upper part of the scar a low clavicle septal ridge extends upward and 

backward to the beak. It is possible that these markings, thus anatomically interpreted, n1ay 

prove to be merely accidental grooves or scratches on the specimen. 

I Hall, James, Paleontology of New York, vol. 5,pt.l,pp.502-505, 1885. Hall's·Elymella levata,from the Hamilton of eastern New York, has a 

sinuated basal margin and flattened middle surface and can not be included in Elymella. It is possibly a modimorphid or grammysioid. 

2 Miller, S. A., and Gurley, W. F. E., New species of Paleozoicinvertebratafroin illinois and other States: Illinois State Mus. Nat. Hist. Bull.ll, 

p. 15, pl. 2, figs. 11, 12, 1896. 
MOLLUSCA. ~43 

The type and only specimen. is 25. millimeters long, 13 millimeters high, and 3 millimeters 

deep. 

Locality: Chapman sandstone, Edmunds Hill, Chapman Township, Aroostook County, 

Maine. 

U. S. N~tional Museum, catalogue No. 59764. · 

Oomzxtrisons.-r-Elymella,. harrisi is very similar in appearance to Edmondia? debilis 1 and 

Edmondict? ]Jrmlonga 2 De Koninck, from the "sub-Carboniferous" etage II, of Pauquys and 

W aulsort, Belgium. 

Both these species are Elymellas, as bas already been indicated. In Edmondia? zJrrelonga 

the anterior end is much shorter and in E. debilis it is slightly longer than in E. harrisi. E.- harrisi has a more arcuate cardinal line and is somewhat less gibbous than either of the Belgian 

species. From I-Iall 's three species. of Elymella, E. harrisi differs in being slightly more elongated 

trans.versely, and in having a narrower, sharper, and less. elevated umbo. 

Genus GLOSSITES Hall. 

Glossites I-lall is another of the several Paleozoic lamellibranch genera founded on external 

characters. The form is easily recognizable by the transversely elliptical outline and characteristic very depressed convexity. .Hall's original diagnosis 3 of the genus is as follows: 

Glossites. n. gen. (Type, Gloss·ites ling·ualis' Hall). Shell equivalve, inequilateral, narrowly or broadly elliptical 

in outline. Anterior end short, margin declining from beak and curving below. Posterior end large, narrowly or 

broadly l'Olmded at the extremity. Beaks small and appressed, subanterior, or in advance of the anterior third. Cardinal line long, gently arcuate. Umbonal. slope not defined, prominent above and usually merging into the general 

convexity of the .surface about the middle of the length. Surface marked by fine concentric strire of growth, which 

are often raised into sharp, sublamellose elevations or more rarely by stronger concentric ridges. Obscure radiating 

str.ire are rarely observed. Hinge-line characters undetermined. There is evidence of an elongate lateral tooth or 

fold, and the valves are joined by n strong external ligament. Lunule distinct. Muscular impressions shallow. 

The species of this genus apparently constitute a very natural group, since they present such characteristic features 

of form and smface characters. These sheUs have sometimes been referred to Modiomorpha and to Sanguinolites, but 

they are clearly distinct from either and can not be properly referred to any previously established genus. Some of the 

species in thei1· natural condition have ha.d considerable convexity, or even gibbosity, in the umbonal region; but 

they are evident;Iy thin shells and much compressed. The shell rarely preserves evidence of radiating strire, which 

are scarcely superficial. · 

Examples: Glossites teretis, Plate XCVI, figure 15. Glossites lingualis, Plate XL, figures 16, 17; Plate XCVI, 

figmes 9-11. Glossites ellipticus, Plate XCVI, figure 8. 

In the New York rocks a single extremely rare species (G. teretis I-Iall) occurs in the Onondaga 

(" Corni.ferous ") limestone, but this .is probably not a Glossites but a Modiomorpha, for it has a 

ventral constriction which does not appear normally in Glossites, where the ventral margin is 

convex throughout. If it is a Modiomorpha the genus Glossites is unknown in New York in 

beds below the I-lamilton. In the I-Iamilton of eastern, central, and western New York several 

species occur, by no means rarely, especially in the coarse arenaceous beds of extreme eastern 

New York, though Glossites subten1tis Hall. is the only form described by Hall from the Hamilton. 

In eastern New York Glossites is occasionally found in the Ithaca shale member of the Portage 

formation, though I-lall does not describe any species of the genus from that member. Hall 

described seven species from the sandstones of the Chemung of New York, in which the genus 

oceurs fr01n the eastern to the western part of the State, though it is nowhere abundant, nor, 

indeed, even common. One species, Gwssites amygdalinus (Winchell) ,

4 appears in the lower 

Mississippian. In North America, therefore, Glossites has hitherto been unknown below the 

"Corniferous" but has been questionn.bly re~ognized in the "Corniferous." It is occasional in 

tho I-Iamilton formation, the Ithaea shale member of the Portage formation, and the Chemung 

formu.tion where it attains its greatest development, continuing into the :Mississippian. 

t Do Konlnck, L. G., op. cit., p. 50, pl. 7, figs. 1'7, 18. 

2Jdom, p. 51, pl. 7, figs. 

u Hull, James, Paleontology of Now York, vol. 5, pt. 1, div. 2, pp. xlix-1, 1885. 

4 Scmguinolilcs amygdalint£8 Winchell (Acad. Na.t. Sci. Philadelphia Proc., 1863, p. 13) and Glossilc's amygdalinus Hall (op. cit., p. 501, pl. 40, 

flgs. 13, 14), from tho "Yellow sandstone" at Burlington, Iowa; also recorded from the Mississippian sandstone of Licking County, Ohio (Herrick, 

C. 1:-., Denison Unlv. Sci. Lab. Bull., vol. 3, p. 69, 1888). 
144 FAUNA OF THE CHAPMAN SANDSTONE OF MAINE. 

In Europe Glossites is represented by Sanguinolaria concentrica Goldfuss,t 1832, from the 

Middle Devonian of Ge-rolstein, in the Eifel, and by Orthonata'? solenopsis Barrande. 2 

In South Africa the genus Glossites has been recognized by Reed 3 in the Lowest Fossiliferous 

or First sandstone, now regarded as of the age of the Lower Coblenzian, or the zone of Spirifer 

hercynice ( =8. gaspensis) (middle Eo--Devonian). Reed describes and figures a very large Glossites 

which he regards as somewhat similar to Glossites depressus I-Iall, from the New York Chemung. 

In the Chapman faunas, Glossites is represented by three distinct species which arc there-

. fore the oldest forms of the genus described. · · 

GLOSSITES BARRANDII sp. nov. 

Plate XIX, figures 14, 17. 

cf. 1881. Orthonata (?) solenopsis. Barrande, Syst~me silurien du centre de la Boh~me (Acephales), pl. 258, case 2, 

figs. 8, 9. 

Etage G: Tetin, Bohemia. 

The Chapman species is very similar .to the fragmentary Devonian fossil from Bohemia 

figu-red.by Barrande under the above name. The form is peculiar in its narrow elliptical outline, 

which does not widen, but instead slightly contracts posteriorly; in the umbones, which are far 

removed from the forward end, being situated at the anterior third; and in the' strongly pronounced concentric striation. The Chapman species sho.ws· a peculiar flattening just below the 

hinge line; this area is broken off in the Bohemian shell, where ,a similar structure appears to 

have been present. 

Outline transversely narrow elliptical; length (33.5 millimeters) a little over twice the 

height (15.5 millimeters);' greatest height slightly in advance of the midlength, at about the 

anterior three-sevenths; greatest length about two~ fifths the height above the base. Umbones 

very broad, obtuse, compressed, ·situated at the anterior third; not protruding beyond and 

indeed hardly reaching the hinge line; directly upward, very faintly prosogyrate. Cardinal 

line long, equal in length to 1! times the height; nearly straight, very slightly convex; descending 

posteriorly so that the posterior extremity is two-fifteenths the height below the umbo. Cardinal extremity angular, obtuse, a.bout 110° to 115°. Posterior margin truncate; retrorse above, 

where it is straight or very slightly concave. Posterior extremity at the rounded respiratory 

angle a trifle less than one-third the height above the base. Ventral margin arched·, convex 

throughout, nowhere insinuated or constricted, nearly horizontal in the middle; ascending into 

the rounded forward end only very slightly more strongly than into the posterior end~ Extreme 

lowest point at the n1idlength. Anterior end well developed, rounded in a nearly symmetrical 

deep parabola; anterior extremity three-sevenths the height above the base. No concavity in 

front of the beak. · 

'l'he shell is very depressed convex; the greatest depth, 2.2 millimeters, is equal to about 

one-seventh the height of the valve or one-fifteenth the length, and is situated at the midheight 

or a trifle above, and at the anterior three-sevenths the length. The postumbont_tl ridge is very 

depressed, broadly rounded, nondefinable; in front of it the surface is evenly and very gently 

convex, the umbones depressed. Between the region of the umbonal ridge and the hinge line, 

nearer the latter, is a radial sulcus which produces an abrupt flattening ·of the surface as far as 

the hinge line. This flattenmg below the hinge line is well indicated in the figures. In front 

of the umbones there appears in the specimen a faint furrow extending horizontally forward 

and slightly downward, subparallel to the upper anterior margin and approaching the front. 

margin. There is no flattening above it. This may indicate a lunette; or it may be merely an 

accidental. feature. The hinge line appears to have been occupied by a very narrow, almost 

linear ligamenta! groove, but whether this was internal or external can not be ascertained. 

There are no indications of teeth, unless the radial furrows in front of and behind the beak are 

1 See Beushausen, ~ouis, Die Lamellibranchiaten des rheinischen Devon: K. preuss. geol. Landesanstalt Abh., new ser., vol. 17, p. 288, pl. 

26, figs. 10, li, 1895. 

2 SysWme silurien du centre de la BoMme, pl. 258, case 2, figs. 8, 9. From etage G' [Devonian]: Tetin, Bohemia. 

a Reed, F. R. C., Mollusca from the Bokkeveld beds: South African Mus. Annals, vol. 4, pt. 6, No. 11, p. 254, pl. 31, fig. 5, 1904. First sandstone, near Klein Straat Siding. 
MOLLUSCA. 145 

considered as such, but that these furrows really indicate teeth is highly improbable. 'Muscular 

scars or pallial line not in1pressed.' Shell structure unknown, but the shell was apparently 

extren1ely thin, for the surface E.triations and the flattening and furrows below the hinge ar~ 

preserved on the interni.tl1nold or "sculpture cast" nearly as strongly as on the external mold. 

The surface and the "sculpture cast" are covered with strongly pronounced concentric 

stria:-e, which are strongest in the region o~ the postumbonal ridge; behind this they bec01ne 

rather retrorse, and at the posterior radial sulcus they ~re slightly insinuated. Varices are only 

obscurely developed by an occasional concentric line, becoming a trifle stronger for a short distance in crossing the region of the umbonal ridge. The striation continues to the upper anterior 

margin. 

The type and only specin1en, an internal1nold or "sculpture cast," and an ·external1nold 

of the same shell (a left valve) is 33.5 millimeters long, 15.5 millimeters high, and 2.2 millimeters 

thick. · 

'fhe principal distinguishing features of the species are the strong concentric orna1nentation; 

the large anterior end, with the beaks far back, at the anterior third and only slightly prosogyrate; the nai:row, transversely elliptical outline, with hinge line slightly descending, not ascending; 

and the posterior margin retrorse:, nearly straight or slightly concave. · 

Locality: Chapman sandstone, west side of Edmunds Hill, Chapman Township, .Aroostook 

County, Maine. 

U. S. National :Museum, catalogue No. 59765. 

Oom1Jarisons.-The large anterior end with the beaks far back at the anterior third will' 

distinguish the Chapman species from any other known form of Glossites except the Devonian 

fossil from Bohemia already mentioned. In the strong concentric striation there is an approach 

to G. cle1J1'essus I-Iall,· but the New York species may be easily distinguished by its ascending 

hinge iine, rounded posterior end, and shorter anterior end. A still closer approach to the 

Chapman species is made by Gloss·ites lingualis Hall, 1 which occurs in the Chemung at Belmont, 

N. Y. This forn1 has similar strin.tion and a nonascending hinge line, but its posterior end is 

rounded, not straight, or retrorse, nor with angular hinge extremity, and the beaks are much 

more anterior. 

In the strong striation, narrow elliptical outline; beaks far back at the anterior third, and 

truncate posterior margin, Glossites ba?'randii apparently very closely resembles Barrande's 

01·thonata,? solenopsis, from the De-v-onian of Tetin, Bohmnia (etage G'), but unfortunately Barrande's fossil is only fragmentary. It is incomplete near the hinge line, and its real features 

in this unknown region may ultinui.tely prove it to be distinct. The Bohemian shell may be 

distinguished for the present by its being much shorter in height than G. ba?'randii. 

GLOSSITES AMNIGENOIDES sp. nov. 

Plate XIX, figure 20. 

Outline transversely ovoid or spatuloid, widest behind; length (52 millimeters) a trifle over 

twice the height (24 millimeters); greatest height at the posterior end of the hinge at the posterior 

third; greatest length at the ventral fourth. Umbones gibbous, depressed to and not protruding beyond the hinge line; broad, prosogyrate; beaks at the anterior sixth. Hinge line very 

slightl)r convex, nearly straight, equal in length to the height of the shell; ascending mark'edly 

toward the rear, so that the greatest height of the shell is at· the hinge extremity. Posterior 

n1argin long, slightly convex, very retrorse, forming an angle of 45° with the height of the shell; 

posterior extremity at the respiratory angle very near the base (one-fifth or one-sixth the height 

above the base). Ventrril margin depressed arcuate, convex throughout; nowhere insinuated 

nor constricted; nearly horizontal for the posterior three-fifths. The lowest point of the shell 

is below the hinge extremity at the pesterior third, whence the ventral margin ascends very 

slightly to the respiratory angle, extends horizontally forward for one-third the length, and then 

1 Hall, James, op. cit., p. 49i, pl. •!0, figs. 16, 19; not pl. 96, which represents a different species from Mansfield, Pa. 

50245°-No. 89-16--10 
146 FAUNA. OF THE CHAPMAN SANDSTONE OF MAINE. 

ascends strongly into the narrow, rounded anterior end, which includes half the height of the 

shell and one-sixth or one-seventh the length. Anterior extremity at the lower two-fifths of the 

height. The shell is convex throughout, depressed over most of the surface, but a little n1ore 

inflated-convex below the umbones in the a;nterior half of .the shell. Point of greatest depth 

situated a trifle in front of and above the middle; depth of the single right valve 4.2 millimeters, 

or a little less than one-sixth the height and less than one-twelfth the length. There is no 

umbonal ridge, its space being flattened. Hmge features unknown. The anterior muscular 

scar is broadly reniform, of moderate size, situated close to the upper margin of the anterior 

end; no retractile scar discernible. The posterior adductor is much n1ore feebly impressed and 

is very much larger, being at least twice as long as the anterior scar and broadly oval in outline. 

Pallial line extremely obscure, but simple. 

The specimen, an internal mold of the right valve, is marked by obsolescent concentric 

st:i-ire of growth, which leave it almost smooth except for an occasional thin wrinkle or varex. 

The ornamentation, very faint everywhere, is most conspicuous near the region of the. umbonal 

ridge. Length, 52 millimeters; height, 24 millimeters; depth, 4.2 millimeters. 

The distinguishing features of this species are the strongly as~ending hinge line (equal to 

the height) and the long retrorse posterior margin, causing the greatest height of the shell, which 

is at the hinge extremity, to be at the posterior third. The length is only twice the height. 

This is the only species of Glossites in which the characters of the muscular scars and pallial line 

are known. 

Locality: Chapman sandstone, Edmunds Hill, Chapman Plantation, Aroost.ook County, 

Maine. 

U. S. National Museum, catalogue No. 59766. . 

Oomparisons.-In the distinguishing features indicated ~hove Glossites amnigenoides seems 

to be very closely allied to Hall's Glossites teretis,t from the Onondaga ("Corniferous") limestone at L~ttleville, near Avon, Livingston County, N. Y., but G. teretis, besides having the 

·beaks more nearly terminal, also ·differs in having an insinuation or constriction below the 

umbones, which suggests its relationship to the genus Modiomorpha rather than to Glossites. 

Glossites amnigenoides is in general intermediate 'between G. patulus Hall,Z from micaceous 

red sandstones above 0) the Chemung at Mansfield, Pa., and G. procerus Hall, 3 from the higher 

·beds of the Chemung at Mansfield, Pa., and Rockville, N. Y., being more elongated than the 

former and shorter than the latter and also differing from both in some minor features. It 

bears a close superficial resemblance, particularly in outline, to Modiomorpha rigida Hall,4 from 

the Che:ri:mng formation of Allegany County, N.Y. That specie.s has a much more conspicuous 

umbonal ridge but is a moderately ·convex species without ventral insinuation or constriction 

. and is· therefore presumpt!vely. not a Modiomorpha; it may possibly \>e a Glossites. 

As is indicated by the name, the Chapman fossil bears a strong resemblance to the weJIknown Amnigenia catskillensis (Vanuxem), 5 a characteristic form of the Upper Devonian freshwater or estuarine beds, particularly in the large size, ascending hinge line equal in length to the 

height, and long, very retrorse posterior margin; but the Amnigenia is somewhat larger and more 

elongate, ard, what is still more important, it has a modiolopsoid ventral insinuation and occurs 

with a nonmarine fauna; Glossites amnigenoides occurs with a marine fauna. 

GLOSSITES cf. G. DEPREssus Reed (nqt Hall). 

cf. 1904. Glossites aff.? G. depressus (not Hall). Reed, South African Mus. Annals, vol. 4, p. 254, pl. 31, fig. 5. · 

Bokkeveld series, First sandstone (zone of Sp'irifer hercynire): Near·Klein Straat Siding. · 

A third species of Glossites is represented ·in the collections from the Chapman sandstone 

by a specimen which looks as if it might have been the original of Reed's figure cited above 

and is possibly the same species. The Chapman fossil is unfortunately too poorly preserved 

to warrant an extended description or figure, beirig even more fragmentary than the South 

1 Hall, James, Paleontology of New York, vol. 5, pt. 1, p. 494, pl. 96, fig. 18, 1885. 

2 Idem, p. 499, pl. 96, fig. 13. 

a Idem," p. 501, pl. 96, figs. 15, 16. 

• Idem, p. 287, pl. 41, figs. 14-16 (not fig. 17). 

& Idem, p. 516, pl. 40, figs. 1-4; pl. 80, fig. 12. 
MOLLUSCA . 147 

. Africnn shell referred to. The species of Glossites represented is characterized by its large size; 

length a little n1ore than "twice the height; dorsal margin convex, horizontal; posterior margin 

very retrorse with the posterior extremity near the base; umbones well back, at the anterior 

quarter, with a faint, low, subangular umbonal ridge. Height 27 millimeters; length unknown, 

but well over 53 n1illin1eters. 

Locality: Chapn1an sandstone, west side of Edmunds 1-Iill, Chapman Township, Aroostook 

Cou~1ty, :Maine. 

U. $. National Museum, ca1;alogue No. 59767. 

:Family CYRTODONTIDJE Ulrich. 

Genus CYPRICARDITE S Conrad. 

In establishing the family Cyrtodontidre, Ulrich 1 adopted Cyrtodonta Billings as the type 

genus and cited the genern Palrenrca Hall, Angellum S. A. Miller, and "Cypricardites I-Iall and 

n1ost American authors (not of Conrad)" as synonyms. The fan1ily was regarded by him as 

essentially Ordovician, becoming practically extinct· with the close of the Silurian. The genus 

Cypricardites Conrad, with 0. c·urtus as type species, was regarded as not synonymous with 

Cyrtodonta Billings, and Ulrich suggested that "Cypricardites may for a long time to come . 

serve as n. convenient temporary receptacle for those species which, because they are insufficiently known, can not be definitely placed in other genera." 2 

The search for an appropriate genus in which to place a species of the Moose River sandstone fauna has emphasized the confusion of usage into which Conrad's generic name Cypr!-

cm·dites has fuJ.len. My study of the subject leads to conclusions son1ewhat different from those 

of Uh·ich, which were based chieHy on Silurian rather than Devonian material. The following 

discussion 1nay save others the trouble of going over again the tangled evidence by which the 

several related genera of the farnily are supposed to be distinguished. These genera include 

Cypricardites Conrad, Palrearca Hall, Ptychodesma Hall, Cyrtodonta Billings, Vanuxemia 

Billings, and Cyrtodontopsis Freeh. 

In the early part of 1841 Conrad 3 proposed the new genus Cypricardites, which he characterized as follows: . 

Genus Cypricarclites. Equivalve, profoundly inequilateral; hinge with four or five unequal cardinal teeth; 

anterior one largest and most prominent, oblique; lateral teeth short .and very remote from the cardinal teeth. This 

genus is allied to Pterinea of Goldfuss, but it is never properly alated, nor has it the very large muscular impressions 

of that genus; the cardinal lateral teeth are also different; the anterior cicatrix is often deeply impressed; the posterior one not visible in casts of the interilor. This genus abounds in the Silurimi 4 rocks, but I have not seen a species 

from any other recent formation. 

No genotype was designated. Conrad described 16 heterogeneric species from the Ordovician and Devonian. (I-Iamilton and Portage); but these are now distributed among the 

genera :Modiolopsis, Modiomorpha,, Grammysja, Pholadella, Goniophora, Cimitaria, and others. 

The first species described is Conrad's .Oypricardites elo11gatus, f1·om the I-Iamilton fauna· at 

S1nyrnn., N. Y., a species now referred to the genus Cimitaria I-Iall. In most of the copies of 

the work of Conrad tulder discussion there are no accompanying figures, but in 1859 I-Iall 

stated that son1e of the copies of Conrad's paper were accompanied by a lithographed plate of 

illustrations, and a plate purporting to be a reproduction of Conrad's plate is inserted in the 

Fifteenth Annual Report of the New York State Museun1 (1862) .. Upon this plate two species 

of Cypricardites are figured. One of the figures, No. 4, which is labeled only "Cypricardj.tes," 

shows the hinge structure of a typical Cypricardites-Cyrtodonta shell. The other figure represents an external view of the Devonian Oypricardites (now Goniophora) carinata Conrad. If 

the plate subsequently resurrected really acc01npanied some copies of Conrad's work, the inference is that the shell figure(i as No. 4 was intended by Conrad himself as the type of the genus 

1 Ulrich, E. 0., Geology of M:Jnnesota, vol. 3, pt. 2, Paleontology, p. 583, 1897. 

2 Idem, p. 536. 

s Conrad, '1'. A., New York Geol. Survey Fifth Ann. Rept., p. 51, 1841. 

4 Conrad's "Silurill.ll" includ~d the Cambrill.ll, Ordovicill.ll, Silurill.ll, ll.lld the Devonian below the Catskill. 
148 FAUNA OF THE CHAPMAN SANDSTONE OF MAINE. 

Cypricardites. Moreover, it appears that of the 16 so-called species of Cypricardites Com·ad 

the one illustrated on the plate as figure 4 is the only one which express·es the characteristics 

of the genus. The form shown in the figure 4 cite.d, which is Oypricardites curta Conrad, a 

species occurring in the Ordovician of Richmond, Ind., and near Rome, N. Y .. , must therefore 

be taken as the genotype of Cypricardites Conrad. 

In 1847 I-Iall 1 founded the genus. Modiolopsis for Conrad's Oypricardites modiolaris, from 

the beds of Utica and Lorraine age in New York, Ohio, and Indiana. Curiously enough, in 

this work Hall, in citing the species described by Conrad in 1841, rnakes no reference whatever 

to any published illustrations or plate supposed to have accompanied Conrad's paper, though 

other .published figures are accurately cited. Hall's genus :Modiolopsis included not only the 

modioliform shells to which the name Modiolopsis is now restricted, but also all the Ordovician 

shells described by Conrad under Cypricardites, including Oypricardites curta Com·a:d, which 

Hall himself 12 years later recognized as the genotype of Cypricardites Conrad, 1841. That 

the now well-known dimyarian and edentulous :Modiolopsis was originally intended by liall 

to be coextensive with Conrad's concisely characterized. genus Cypricardites is indicated by 

his inclusion in Modiolopsis of the various Ordovician Cypricardites described by Conra<;I. 

Moreover, in a footnote, Hall 2 proposes the substitution of Modiolopsis for Cypricardites, 

saying: 

I find ·myself compelled to abandon the use of the name C)1)ricardites as applied to shells differing so widely as 

these do from the Cypricardia and belonging apparently to the Monomyaria and not Dimyaria. So far as it is possible 

to ascertain, none of the species of the older strata possess two muscular impressions, and therefore do not strictly fall 

under the genus Cypricardites of Conrad. 

The following is Hall's original diagnosis 2 of the genus Modiolopsis: 

Equivalve, inequilateral, elongated, becoming broader posteriorly, umbones near the anterior extremity, which . 

is. marked by a single strong muscular impression, as in Modiola. A sinus often extends from the anterior side of the 

umbones obliquely backwards, leaving the anterior portion separated as a kind of lobe. Surface. marked by fine concentric strire; shell thin. · 

This genus, as defined, includes a very natural group of shells found in the older Silurian strata, some of which 

have been referred to Cypricardia, .Modiola, Pterinea, and other genera. One of the most prominent characters is the 

strong muscular impression which is close to the anterior ma;rgin; this is often visible in the shell, forming a little 

circumscribed elevation, and more conspicuous in the cast, where it is usually well preserved. There is often a slight 

contraction or sinus below or posterior to the umbones, but this is not always conspicuous. The shells of this genus 

are for the most part smooth or marked only by fine concentric lines, indicating the laminre of the shell, and they are 

generally free from angular ridges. Cypricardites modiolaris (Conrad)? 

This description is much less concise than that of Cypricardites Conrad, 1841; all the 

features recognized by Hall were equally well or better recognized by Conrad, and whereas 

Hall erroneously regarded the shells as mon<;>myarian, Conrad correctly understood their real 

nature. Hall indicated no ·characters which would separate these shells from Cypricardites 

as he then understood the genus, so that it seems quite evident that Hall either intended to 

suppress Cypricardites and substitute Modiolopsis in its place, or else he regarded Conrad's 

, genus as founded on some Devonian shells of a different nature. Modiolopsis is now restricted 

to such edentulous dimyariari modioliform shells as are congeneric with jf. modiolaris (Conrad), 

which, of course, are very distinct from Cypricardites-Cyrtodonta. 

On March 1, 1858, Elkanah Billings,3 paleontologist of the Geological Survey of Canada, 

communicated to the Director of the Survey his report for the year 1857 including the description of the new genus Cyrtodonta for certain Ordovician forms, which since 1859 have been 

generally regarded as identical with Cypricardites Conrad. The date of publication is not 

certainly known. Billings's report for 1857 was transrnitted to the director of the Geological 

Survey of Canada, W. E. Logan, March 1, 1858, and the entire Annual Report of Progress for 

1 Hall, James, Paleontology of New York, vol. 1, pp. 1"57, 294, 184i. 

2 Idem, p. 157. 

a Canada Geol. Survey Rept. Progress for 1857, p. 179, figs. 1-14 ( Cyrtodonta rugosa Billings is described on p. 1 i9 and shown in figs. 1, 2. Tho 

species is from tho "Fourth Chute of tho Bonne Chore, Pauquettes Rapids, and at La Petito Chaudiere Rapids near the city of Ottawa, north side, 

associated with numerous fossils of the Trenton and Black River formations"). · 
MOLLUSCA. 149 

1857 was transmitted by Logan to the lieutenant governor March 31, 1858, so that the publication appeared smne tin1e in 1858 later than March 31. However, the portion of the paleontologic report containing the description of the fossils, including the description of the new 

genus Cy:rtodonta Billings, was published at Montreal as a separate pamphlet of 31 pages with 

the title "Canadian fossils, containing description of new genera and species, from the Silurian 

and Devonian formations of Canada, etc." The date of this pamphlet is unknown, but it may 

hav-e been March, ,1858, the date given by B. E. Walker in his "List of the published writings 

of Elkanah Billings, F. G. S." 1 This portion of Billings's report was again published in 

December, 1858, under the. title "New genera and species of fossils from the Silurian 

and Devonian formations of Canada." 2 In tllis article Cyrtodonta is described on page 431 

and this. description is com1nonly regarded as the original diagnosis of the genus; but apparently both the Report of Progress for 1857 and the separate pamphlet mentioned above antedate the article in the Canadian Naturalist. 3 

'rhree years later Billings 4 saild of the genus Cypricardites: 

·As for myself, I must say that when I described the genus Cyrtodonta, I ·was aware of Conrad's description, but 

considered, as I do now, that the genus, having been suppressed by Prof. Hall and never acknowledged by paleontologists or quoted by them except as a synonym, was perfectly obsolete. 

So far as Billings was aware, no figures of the real Cypricardites had ever been published; 

and seven species of Cypricardites :figured and describ~d by Conrad in 1842 5 all represented 

entirely different shells which would now be included in Cypricardinia, Cimitaria, Goniophora, 

Plithonin., etc. Besides, Billings considered the name Cypricardites inappropriate, the shells 

· having, in his opinion, no resemblance to Cypricardia. 

"l''he following is Billings's diagnosis of the genus Cyrtodonta: 

Equivalve, in equilateral; umbones nt:lar the anterior end; general form obliquely tumid,· transversely subrhomboidal or ovate; posterior extremity larger than the anterior and usually broadly rounded; two muscular impressions, 

of which the posterior is superficial and 1;he anterior sometimes deeply excavated; three oblique, often more or less 

curved, anterior teet11 situated either beneath or a little in front of the umbones; two or three remote posterior lateral 

teeth parallel with the hinge line; pallialli·ne simple; ligament external; some of the species have a narrow area (escutcheon) between or behind the bea.ks. 

Billings did not emphatically designate any particular genotype but described ten species 

(giving figures of n1ost of them) :frmn Ordovician rocks throughout Canada frmn Anticosti. to 

Lake I-Iuron and called attention to a few also occurring in the New York Ordovician. The 

first species described and :figured by Billings, 0. rugosa Billings, well illustrates the generic 

features ~escribed and what would be considered a normal expression of Cyrtodonta and n1ay 

be taken as the genotype. 

While Billings was working on these widesprertd and important Ordovician lamellibranchs 

in Canada, }IaU was working on the An1erican species of Conrad's Cypricardites s. str. In 1857 

I-Iall prepnred ·a paper in which he promulgated the new genus Palrearca to· include Palcearca 

(forn1erly Edmondia) ventT'icos·a Ilall and Palcearca saffordi Hall, from the Ordovician of Ten-· 

nessee, and A mbo11:ychia obtusa, Oardiomorpha vetusta, Edmondia subtruncata, E. subangulata, 

·E. ventricosa, lelodiolopsis latus, Emd Jf. subs,patulus, frmn the Trenton limestone, all described 

in "Paleontology of New York," volun1e I, 1847. Conrad's Oypricardites curta, the genotype· 

of Cypricardites, which I-Iall in 184 7 included in Modiolopsis, is not included in Palrearca, but. 

in a later report 0 I-Iall'says: "This species is probably distinct from Modiolopsis." 

I-Iall's paper on the genus Pa1rearca was not published, however, until1859, when, accordingto Billings, it was issued in a small 18-page pamphlet as an advance extract from the Twelfth 

Annual Report of the New York State :Museum. This pamphlet appeared probably ju May or 

June, as it is noticed in the July number of the Americar~ Journal of Science, under the title 

1 Canadian Roc. Sci., vol. 8, No. G, p. 372, 1901. 

2 Ca.nadil:ur Naturalist and Geologist, vol. 3, pp. 419-444, 1858. 

3 Fischer, Paul (Manuel do conehyliologie, 1887, p. 992), cites the genus Cyrtodonta Billings as of date 1853. 

• Canadian Jour., July, 1861. 

6 Acad. Nat. Sci. Philadelphia, Jour., vol. 8, pp. 244-246, pis. 12, 13, 15, 1842. 

o New York State Mus. Twelfth Ann. Rept., p. il, 1859. 
150 FAUNA OF THE CHAPMAN SANDSTONE OF MAINE. 

"Contributions to the paleontology of New York; being some of the results of investigations 

made during the years 1855-1858, by James Hall, Albany, N. Y., 18 pages, 8°, 1859." The 

paper reappeared in the Twelfth Annual Report of the State ¥useum, pages 8 et seq. (1859), 

and in "Paleontology of New York," volume 3, pages 271, 523, etc. (1860, according to Billings). I have not seen the original pamphlet and the following description of Palooarca is 

reproduced from the museum report: 

Shell equivalve, very inequilateral, ovoid or rhomboid-ovate, gibbous or ventricose; umbones subanterior; 

anterior extremity abruptly rounded or sometimes obliquely subtruncate; anterior muscular impression very strongly 

marked (usually a deep round pit); the posterior impression obscurely defined; anterior teeth three, four, or five 

oblique, placed beneath or in advance of the umbones with two or three remote oblique posterior or lateral teeth; 

pallial line simple; ligament external; ligamenta! area often deep and wide, striated. The shells of this genus vary 

in the development of the ligamenta! area and in the teeth of the hinge. line, the latter often becoming much thickened, and some of them obsolete with age; the anterior muscular impression is very deep. and strong, while the 

posterior one is superficial, though the shell is always thinner at that point, as frequently observed in' worn specimens. 

Hall figures Palrearca ventricosa and P. saifordi, showing the hinge and internal features, 

and gives the list of species from the Trenton limestone of New York already cited as included 

in Palooarca. He states that "this genus was proposed in 1847, and the descriptio~1 has been 

printed in the Paleontology of New York, volume 3, with the accompanying illustrations." 

I can find no trace of any mention of Palooarca in 1847, and that date is evidently a 1nisprint 

for 1857. · 

In the works cited Hall states that Cypricardites Conrad, 1841, and Palooarca flail, 1859, 

appear to be identical, and that heretofore the genus Cypricardites ·had been almost entirely 

overlooked. He reproduces the original description of Conrad's genus, and says: 1 

The description corresponds in many respects with that of Palrearca, and the illustration given· by Mr. Conrad 

likewise resembles that genus. Should an examination of the typical species prove the two identical, the latter name 

will give place to that of Cypricardites. · 

Hall thus suggests that his generic nan1e Pa1ooarca should perhaps be abandoned. In this 

quotation is the first direct reference to the illustration given by Conrad of the generic characters of Cypricardites. Hall introduces an outline sketch. of. a :figure showing these characters and states: 

This figure is copied from the original figure of Mr. Conrad, accompanying the description of the genus in 1841. 

The plate upon which this occurs was engraved to accompany the Annual Report of 1841; but unfortunately only a 

small number were ever distributed so far as known to the writer. * * * At the time I proposed the generic name 

Palrearca in 1847 [?misprint for 1857], I had overlooked the description and figures of Cypricardites, and it is only since 

the printing of that part of volume 3, Paleontology of New York, that my attention has been directed to the subject 

of the preceding note. i 

The reviewer 2 of Hall's advance pamphlet states that the genus described by Hall, 

Palm areais the same that was called Cyrtodonta by Billings in the Canada Geol. Rep. for 1857, p. 179; and Billings's name therefore has the priority. Mr. Hall states that the genus is in the third volume of his Paleontology. Unfortunately the 

volume is not published, and much more may yet be lost to the author, as priority of publicationis the only just basis 

for any claim. Mr. Hall at the same time observed that the genus Cypricardites of Conrad was based on a shell probably 

of similar character. 

The reviewer adds that, as Palooarca is not related to Area, nor Cypricardites to Cypricardia, 

"both the names Palooarca and Cypricardites are objectionable.;' 

In an article in the Canadian Journal of Industry, Science, and Art for July, 1861, Billings 

gives a short history of the 'generic names Cyrtodonta, Palooarca, and Cypricardites, in which he 

reiterates the literary objection to the name Cypricardites and says that Cyrtodonta therefore 

ought to be retained. Moreover, he adds, Conrad's genus was heterogeneous, and no type was 

designated. With regard to the :figures supposed t9 have accompanied Conrad's paper of 1841, 

Billings states that "he [Conrad] did not give any illustrations" and practically accuses Hall of 

having suppressed Conrad's generic name Cyprica:rdites in order that he might apply his own 

generic name Palooarca to these shells. Billings goes on to say that when Hall discovered that 

1 New York State Mus. Twelfth Ann. Rept., p. 14,1859. 2 Am. Jour. Sci., 2d ser., vol. 28, p. 149, 1859. 
• 

.MOLLUSCA. 151 

Cy:rtodonta Billings antedated Pal.rearca Hall, the New York savant resurrected and published 

Conrad's supposed figure in order to suppress Cyrtodonta by reviving Cypricardites. 

In reply to this article I-Iall published a short "Note on the genus Cypricardites," 1 in 

which he stated that the slight zoologic error suggested by the name Cypricardites hardly 

warranted expunging the name, citing other names, such. as Athyris, which are commonly 

accepted, though much n1ore glaringly inappropriate. Hall appended to this note a reproduction 2 

of the plate which is stated to have accompanied Conrad's paper of 1841 and on which is figured 

the hinge structure of Cypricardites. 

Was this plate really published in 18411 The general trend of the facts of the case and, 

especially, the peculiar circumstnnces that I-Iall in his work before 1859 makes no reference 

whatev-er to these illustrations, ]tend ground to the suspicion that· tbjs plate was not really 

published before 1859. This suspicion is accentuated by Billings's remark 3 th.at "he [Conrad] 

did not give any illustrations." Again, as late as 1894, Ulrich 4 says that in 1859 "Hall·reproduced a sketch of the things that. had been overlooked among the manuscript left by Conrad." 

The importance of determining whether or not a plate accompanied Conrad's work lies in 

the fact that if Cypricardites was illustrated, as is alleged, in 1841, then the genus Cypricardites 

is valid beyond question; wherefLS if the genus was not illustrated in the manner alleged, then 

the heterogeneity of the assemb1lage include.d by Conrad under Cypricardites and the absence 

of any genotype might leave room to argue against the assumption of priority for the name 

Cypricardites ov-er that of any related group dissociated therefrom prior to 1859. 

Ev-idence that the plate was published in 1841 is given in the assertion by Hall, 5 previously 

cited, that the figure of Cypricnrdites under discussion ''is copied from tl?-e original figure of 

Mr. Conrn,d accompnnying his description of the genus in 1841. The plate upon which this 

occurs was e,ngrav-ed to accompany the annual report of 1841; but unfortunately only a· small 

nun1bcr were ev-er distributecJ., so far as known to the writer." The only other proof that any 

of these plntes were ev-er" distribu~ed" is given in a later statement by I-Iall, 6 in which he says: 

I [Hall] inferred that only a small number of the copies of the plate were published with the report [of Conrad, 

1841"1; but .it may have been more extensively distributed than I supposed, for I have found five copies among my 

own volumes. 

'rhe plate of illustrations certainly resembles the work of Conrad, but there is no reference 

to these illustrations in geologie literature prior to 1859, by Billings, I-Iall, or Conrad himself, 

or by Salter, McCoy, or other European paleontologists. Search among public and private 

libraries would clear this point, but such a stupendous task is not fundamentally necessary, 

chiefly because of the fact that, of the 16 species of Cypricardites described in 1841 by Conrad, 

0. curta, whether a figure was published or not, is the only one which really possesses the type of 

dentition mentioned by Conrad, the other 15 species being generically decidedly different shells . 

Since 1859 Cypricardites Conrad, 1841, Cyrtodonta Billings, 1853, and Palrearca I-Iall, 

1859, hav-e been c01ninonly regarded as indicating the sarne genus, the controversy being as to 

which na1ne should be used. 

Salter 7 regards Cypricard.ites Conrad as an illegitimate name and adopts Palrearca Hall 

in preference to Cyrtodonta. lie retains this name in other works but is the only paleontologist 

who aqopts it, the reason lying in his assumption that the genus Palmarca was founded in 184 7, 

as stated by I-Iall, so that it would have· priority over Cyrtodonta Billings, 1858. In the 

text above referred to (p. 546) Salter cites the genus Cyrtodonta Billings as having "appeared 

in 1848 beautifully illustrated," but as Palrearca was not published or even otherwise disseminated until 1859, it rnust be u,bandoned. 

I Now York State M:us. Fiiteenth Ann. Rept., pp. 192-193, 1862. 

2 Idem, pl. 11. 

s Canadian Jour., July, 1861. 

4 Paleontology of Minnesota, vol. 3, p. 535, 1894. 

G Now York State M:us. 'l'welfth Ann. Rept., p. 14, footnote, 1859. 

a Now York State M:us. Fifteenth Ann. Rept., p. 192, 1862. 

7 Mom. Gool. Survey Great Britain, vol. 3, p. 546; also see Bigsby, J. J., Thesaurus Siluricus, p. 139, 1868. 
152 FAUNA OF THE CHAPMAN SANDSTONE OF MAINE. 

Cyrtodonta is used by Safford/ who figutes several species, but otherwise in the United 

States Cypricardites Conrad has been used in preference to Cyrtodonta, largely because of the 

adoption of Conrad's nam~ by Hall and by Miller. 2 . 

In 1884 shells of this type were for the first time certainly recognized in rocks higher than 

the Ordovician, when Beushausen 3

. described three species from the Lower Devonian of the 

Harz Mountains under the name Cyrtodpnta-0. beyrichi'-Beushausen, 0. kayseri Beushausen, 

and 0. declivis (Roemer). 4 

Beushausen, like the Canadian and British paleontologists, regards Cypricardites Conrad, 

1841, as less valid than Cyrtodonta Billings, 1858, chiefly because of the heterogeneity of the· 

species included by Conrad in Cypricardites. In 1891 Frech 5 adopted Cyrtodonta for the same 

reason. He described and figured 0. declivis (Roemer) and a new species, 0. orbicularis, both 

from the Harz Eo-Devonian. Frech 6 also described a new genus or subgenus, Cyrtodontopsis, 

for cyrtodontiform shells having five or six crenulated 7 cardinal teeth, of which the first and 

third in the right valve join above, forming an inverted V within which is. the second tooth. 

The ligamenta! area is strongly striated. The genus is restricted to the Lower Devonian, three 

species being described from the Rhine district and one from the Harz Mountains. Frech considers Cyrtodontopsis a subgenus of Gosseletia. . 

Beushausen 8 .recognized neither Cyrtodonta nor Cyrtodontopsis in the Rhenish Province. 

illrich/ working on the American Ordovician shells of the Cypricardites-Cyrtodonta group, 

was the first to suggest that Cypricardites Conrad might not be identical with Cyrtodonta Billi,ngs, of which Palrearca Hall is a synonym. illrich called attention to the fact that in Cypricardites, according to Conrad, there are five cardinal teeth, whereas in all the Ordovician shells 

of this type which have been since examined and referred to Cyrtodonta or Palrearca, the usual 

number is three. Two teeth are not uncommon, but four are very rare. According to Conrad, 

also, the anterior cardinal tooth is the "largest and most prominent," but this is not the case· 

in the Ordovician shells examined by Ulrich, nor in those figured by Hall as Palrearca or by 

Billings as Cyrtodon ta. Moreover, the figure of Cypricardi tes credited to Conrad represents 

the cardinal teeth as radiating downward from the beak, whereas in all the shells of this type 

subsequently examined the teeth are subparallel and more nearly horizontal than vertical or 

radial · 

Ulrich thus r~ises the question whether Conrad correctly described and illustrated the 

hinge of the genus Cypricardites ( 0. curta Conrad); but in the absence of definite knowledge 

to the contrary it must be assumed for the present that Conrad's diagnosis is correct, and hence 

that Cypricardites represents a different type of shell from that called Cyrtodonta Billings, 

1858 (Palrearca I-Iall, 18.59). As all the Ordovician shells examined exhibit a type of structure 

conformable with that of Cyrtodonta, that name is applied to them. 

Ulrich makes it quite clear, however, that if Oypricardites curta Conrad is congeneric with 

Cyrtodonta, Conrad's name ought to have priority. That they may be congeneric is suggested 

by Ulrich's proposed retention of Cypricardites Conrad for 0. curta Conrad and incertce sedis 

of this type, and by the suspicion that Conrad's diagnosis and figure were incorrect. Ulrich 

seems to overlook the well-known variability in dentition of these schizodontic shells and the 

t Geology of Tennessee, p. 287, pls. e, f, 1869. 

2 American Paleozoic fossils, 1877; North American geologv' and paleontology·, 1889. 

3 Beushausen, Louis, Beitrage zur Kenntniss des Oberharzer Spiriferensandsteins und seiner Fauna: A bh. geol. Specialkarte von Preussen, 

etc., vol. 6, Heft 1, pp. 67 et seq., pl. 3, figs.2-5. 

4 Lucina declivis Roemer, C. F., Die Versteinerungen des Harzgebirges, p. 25, pl. 6, fig. 19, 1813; M egalodon declivis D'Orbigny, Prodrome de 

paleontologie, vol. 1, p. 75; Pterinea declivis Roemer, Beitrage zur geologischen Kenntniss des nortwestlichen Harzgebirges, pt. 3, p. 123, pl. 18, 

fig. 5, 1855. 

6 Frech, F., Die devonischen A viculiden Deutschlands; ein Beitrag zur Systematik und Stammgeschichte der Zweischaler: A bh. geol. Special-

. karte von Preussen, etc., vol. 9, Heft 3, pp. 130 et seq., pl. 4, figs. 2, 3, 189L 

s Idem, p. 125, pl. 13. 

1 In the genotype, Gosseletia ( Gyrtodontopsis) kayseri Frech, the teeth are not crenulated; in G. (C.) quarzitica Frech they are crenulated. 

Of the four species of Cyrtodontopsis described by Frech these two are the only really cyrtodontiform shells. (See Drevermann, F., Die Fauna 

der Unter Coblenz Schichten von Oberstadtfeld bei Daun in der Eifel: Palaeontographica, vol. 49, pp. 84; 85, pl. 10, figs. 4-9, 1902. 

s Beushausen, Louis, Die Lamellibranchiaten des rheinischen Devon mit Ausscbluss der Aviculiden: K. preuss. geol. Landesanstalt Abh., 

new ser., vol.17, 1894. · 

o Ulrich, E. 0., The lower Silurian Lamellibranchiata of Minnesota: Geology of Minnesota, vol. 3, pt. 2, Paleontology, pp. 534-536, June 16, 1894 .. 

• 
MOLLUSCA. 153 

consequent possibility that Conrad's diagnosis, from a fortuitous specimen may illustrate a 

r11rer. type of tooth structure. This point is of greater importance than has hitherto been recognized 11ncl possibly involves the consideration which induced authors to regard Cypricardites as 

identical with Cyrtodonta or P11lrenrca, althm,1gh 'frmn the descriptions given above it is evident 

that these genera are quite distinct. 

Drevermruu1/ in 1902, gave some· good illustrations showing va.riations in the dentition of 

shells referred to Cyrtodonta and Cyrtodontopsis. The latter genus Drevermann affiliates with 

Cyrtodont11 rather th11n with Gosseletia, where it had been placed by Frech. Cyrtodontopsis, 

according to Drevermann, differs from Cyrtodonta (or, rather, from the German Eo-Devonian 

shells referred by 11uthors to CJI·todonta) in having an oblique outline, and particularly in 

h11ving 11ll the teeth directed strongly backward, whereas in Cyrtodonta the front cardinal teeth 

11re directed obliquely forwn,rd. On this distinction in the direction of the cardinal teeth Drevern1mu1 includes in. the genus Cyrtodonta a new species, Oyrtodonta dunensis, the first Cyrtodonta 

proper described from the :Rhine pi·ovince. This species, originally described by Drevern1ann 

from the Lower Coblenzian of Oberstadtfeld, near Daun, in the Eifel, has been recorded by the 

same author 2 as apparently occurring in the Siegen graywacke of Seifen,.near Dierdorf, in the 

W esterwald. Drevermann shows that ~!odiomorpha follmanni. (Beushausen) is congeneric 

with Oy'rtodontopsis kayseri Frech and, as in that species, its teeth are not crenulated. 

The distinction between Cyrtodontopsis and Cyrtodonta indicated by Drevermann, that 

in Cyrtodontopsis the teeth are. directed backward, whereas ih Cyrtodonta the front cardinals 

are directed obliquely forward-can not hold, for, on account of the variability in dentition of 

these schizodontic shells, it sometimes happens that the front cardinals are directed forward 

in Cyrtodontopsis, as in 0. follmanni (Beushausen) ,S 11nd vice versa in Cyrtodonta. 

Of course the European Devonian shells referred to the genera Cyrtodontopsis and Cyrtodontl1 11re 11ll distinct from Cyrtodont~ Billings in several in1portant and interesting respects. 

In Cyrtoclonta Billings (and, according ~o Ulrich, in all the Ordovician Cyrtodonta-Cypricardites shells hitherto examined exeept Oypricardites curta Conrad), there are commonly only two 

cardin11l teeth, someti1nes t~1ree, rarely four; the teeth are directed bach..--wa.rd, almost horizontl1lly, and the forward teeth are the weakest. In the European Devonian shells, on the other 

hand, there are five cardinal teeth, rm·ely four, and commonly six or seven; the teeth are obliquely radi11l, and commonly the front one or two' cardinals are nearly horizontal, but if so are 

directed forward, and the front teeth are the strongest. · 

It is of interest to note that these German Devonian shells are the only Devonian forms 

which really answer to the generic description of the Ordovician Cypricardites Coru·ad s. str., 

1841 (0. cu1·ta Conrad). As for the present, Conrad's description must be considered authentic 

and illustrative of the real and normal d~ntal structure of Oypricardites curta, it follows that 

·tho Eo-Devoni11n shells commonly referred toCyrtodonta and Cyrtodontopsis are at least approxin111tcly congeneric with Cypricardites. The nan1e Cyrtodontopsis Frech will have to be restricted 

to shells which have crenul11ted teeth. Those Ordovician: shells which have the ca,rdinal teeth 

horizontuJ, only three in number, and the strongest one not in front, and which have been 

coininonly regarded by I-Inll, :Miller, Billings, and others as identical with Cypricardites, Cyrtodontl1, and Palrearca, will have to be called Cyrtodonta Billings, of which Palrearca I-Iall is a 

synonyn1, but which is quite distinct fron1 Cypricardites so far as is at present apparent or 

ascertain,aQle. 

The genus Ptychodesma Hall and Whitfield 4 was founded upon P. knappi.anum Hall and 

Whitfield, a Middle Devonian shell having the aspect of the more depressed..:convex Cypricardites 

or Palrearca types; but the nature of its hinge teeth is unknown, and it has what was regarded 

as a characteristic ligamenta! structure. The escutcheon is very strongly pronounced, deepen1 Dl'cvcrmann, F., Die Fauna derUnter Coblenz Schichten von Oberstadtfeld bei Daun in der Eifel: Palaeontographica, vol. 49, pp. 84, 85, pl.10, 

figs. 4-!J, 1902. 

ll Palo.e:mtogro.phlca,. vol. 50, p. 241, 1904. 

3 Sco Dl'cvcl':nunn, F., op. cit., fig. 5. 

4 Ho.Jl, James, and Whitficl<f, R. P., Descripti:m of new species of fossils from the vicinity of Louisville, Ky., and the Falls of the Ohio: New 

York Stuto M6s. 'l'wenty-fourth Ann. Rept., pl. 12, figs. 1-6, 1Si5. 
154 FAUNA OF THE CHAPMAN SANDSTONE OF MAINE. 

ing and widening with the growth of the shell, and it is strongly striated or ridged longitudinally; 

The ligamenta! strire or ridges arch over the umbo and are straight posteriorly, but, instead of 

being parallel to the hinge line, are slightly inclined or oblique to it and parallel with the cardinal margin. A similar ligament occurs in· the late Silurian shells referred by Lindstrom t 

to "Ptychodesrna" nilssoni Risinger, a species from the later Silurian limestones at Djupvik, 

Gotland. The Gotland shells seem to differ from Ptychodesma in being apparently edentulous 

and in possessing an internal cartilage pit. The species is represented in England, according 

to Lindstrom and McCoy, by Modiola? antiq_ua Sowerby and },fytilus (},fodiolopsis) gradatus 

Salter, from the Upper Ludlow. The occurrence of hinge teeth was noticed in 1885 by Hall/ 

who mentions the existence of" two or more cardinal teeth." Nettelroth 3 repeats the description of Ptychodesma given by Hall and Whitfield, but adds nothing new. Ulrich 4 places the 

genus Ptychodesma in the family Cyrtodontidre, regarding it as the last surviving member of the 

family. The real tooth structure in Ptychodesma was described and figured for the first time 

in 1900, when Kindle 5 showed that there are two long posterior laterals near the posterior end 

of the hinge line and parallel to it; and, under the umbones, there are "about three" short 

oblique radial cardinal teeth. Kindle gave a good figure 6 of the interior of a silicified left 

valve showing four cardinal teeth and five sockets, indicating the existence of five cardinals in 

the right valve. The second and third cardinals in the left valve unite above, forming the 

inverted V (A) which is so common in the German Eo-Devonian "Cyrtodonta" and "Cyrtodontopsis" and which also, ::ts in. ·the German shells, incloses the third socket in the left valve, 

corresponding to the third or middle tooth of the right valve. Kindle's figures indicate that the 

ligamental charact9ristics noted by Hall and Whitfield are of less importance and constancy than 

had been previously supposed. There can be fl:O doubt· of the relationship of Ptychodesma 

to the Cyrtodontidre or the Cypricardites; indeed, P. lcnappianum is remarkably similar to 

Oypricardites curta in having four or five cardinal teeth, as described for Cyp:r;icardites by Conrad, 

and not six or seven; moreover, these teeth are radial, riot horizontal, and the longest one iS" in 

front. Ptychodesma agrees more nearly with Cypricardites than do the German Eo-Devonian 

shells previously mentioned, and with present knowledge Ptychodesma n1ust be considered a 

synonym of Cyprieardites Conrad s. str. · · 

In conclusion it seems necessary, therefore, to restrict the term Cypricardites to such 

'cyrtodontiform shells as are congeneric wit\1. 0. curta Conrad, in having the cardinal teeth 

radial, not horizontal, and five in number, sometimes six or seven, rarely four. The forward 

one or two are the stronger, and may be in some specimens horizontal, but if so ·are directed 

forward. In the Devonian members of this group (the shells usually called Cyrtodonta and 

Cyrtodontopsis by Beushausen, Frech, and Drevermann, and Ptychodesma by I-Iall and Whitfield) the second or third cardinal tooth is usually inclosed in an inverted V or horseshoe-shapQd 

loop formed by the union dorsally of the cardinal tooth in front and behind. The teeth are 

variable in their development, even in the same species. 

The term Cyrtodontopsis Frech will have to be restricted to those forms of Cypricardites 

which have crenulated te~th. Cyrtodont~ Billings will be retained for shells differing fron1 

Cypricardites as here lin1ited in having commonly only three cardinal teeth, frequently only 

two, rarely four. The teeth ate directed backward, are horizontal or nearly so, and not essentially radial, and the front one or two are not the stronger. Pal~arca I-Iall is a synonym. 

V anuxemia Billings, which has frequently been confused with Cyrtodonta and Cypricardites, 

is a vertical Ambonychia-like or Megambonia-like shell. As no fos.sil"has been found in the 

Maine faunas comparable with this type, I do not feel at liberty to enter here into any discussion of the genus. 

1 Angelin, N. P., and Lindstrom, G., Fragmenta silurica, p. IS, pl. 2, figs. 21-22; pl. 19, figs. 5-6, 1880. 

2 Hall, James, Paleontology of New York, vol. 5, pt. 1, pp. xxix, 352, 1885. 3· N ettelroth, Henry, Kentucky fossil shells; a monograph of the fossil shells of the Silurian and Devonian rocks of Kentucky, pp. 201-202, pl.ll, 

figs. 13-18, 1889. - · 

• Ulrich, E. 0., PaleontologyofMinnesota, vol. 3, pt. 2, pp. 486,533,1894. 

5 Kindle, E. M., The Devonian fossils and stratigraphy of Indiana:· Indiana Dept. of Geology and Nat. Res. Twenty-seventh Ann. Rept., 

pp. 671-672, pl. 15, figs. 2-2c, 1901. 

o Idem, pl. 15, fig. 2c. 
MOLLUSCA. 155 

The Cypricardites-Cyrtodonta group are among the don1inant fossils of the Ordovician 

in A1nerica and Europe, but are exceedingly rare, if, indeed, they have been recorded at all, 

in the Silurin.n. In the Lower Devonian they have already been indicated from the Rhenish 

and I-Iercynin.n strata. A!.odiomo?'pha sellowi Clarke/ from the Devonian fauna of the Rio 

Mn.ecuru, Para, Brazil, appears t.o be a member of this group, rather than of Modiomorpha. 

It is apparently congenerie with "A!.odiomorpha" follmanni (Beushaus~n). In the Middle 

Devonian no fossils of this group have hitherto been recorded, but 1Vyassa subalata Hall, 2 from 

the New York I-Imnilton, is very probably a member of the assemblage, for it is closely related 

to Cypricardites, particularly to the German Eo-Devonian fossils here referred to that genus,. 

differing chiefly in having the cardinal teeth more numerous and more irregular. 

Finally, Ptychodesma knappianum appears to be a typical Cypricarclites. The species is 

from the llamilton of New York and beds of similar age in I(entucky, Ohio, and Indin.nn.. 

I-Iall 3 also describes Ptychodesma nanum and P. minor, fron1 the Upper Devonian, the 

former from the lower half of the Ithaca shale member of the Portage formation, the latter 

fron1 the Cayuta shale n1ember of the Chemung formation. In both of theso species the dentition is unlmown; hence it· can not be definitely stated that they belong to the group under 

discussion. 

0YPIUCARDITES DETROITENSE sp. nov. 

Plate XXIII, figures 14, 15. 

Shell transversely oblique, equivalve; very inequilateral. Rhombic, obliquely extended at 

an angle of about 35° with the hinge line. Length (35 millimeters) very nearly one and onehalf ti1nes the height (24 millirrwters), widening posteriorly, so that the greatest height is at 

the posterior third, which is one and one-half times as high as the height of the shell under the 

beaks. Gren.test length at or above the midheight. Umbones anterior but not ternlinal; 

situated between one-fourth and one-fifth the length from the front; prosogyrnte. Cardinal 

line straight, very slightly ascending, equal in length to three-fourths the height of the shell. 

Cardinal extremity obtuse. Posterior margin strongly arcuate and evenly rounded, fonning 

a smnicircle as far as the ventral extremity at the n1idheight. Postventral region broadly 

rounded. Ventraln1argin rounded, with the lowes.t point at the posterior third or two-sevenths, 

whence the Int:trgin ascends forward into a depressed curve, ~ausing a marked diminution of 

the height toward the front and causing the forwnrd extremity of the shell to be opposite 

tho upper third of the height.· There is no ventral insinuation nor constriction. The anterior end is very short and narrow, evenly rounded. There is no discern~ble lunule in front 

of the beak. The shells are of moderate or depressed convexity. The depth of the single 

valve is 5 ntillimeters, approximately one-fifth the height or one-seventh the length. The . 

point of greatest depth is at the upper third,· two-fifths the length of the shell from the. front, 

whence the surface dips into an. evenly convex slope in all directions. The beaks are depressed 

convex, incurved, hardly protruding beyond the cardinal line. There is no un1bonal ridge. 

There is evidence sugge~ting the presence of art external ~gament in a long escutcheon, which 

appears to be striated, the strire arching over the region of the cardinal teeth, as in Ptychodesma 

knCLJJ1Jianum, but not so strongly developed. There are two posterior long, narrow,· linear 

laterals in each valve, those of the left valve being above those of the right .. These teeth are 

1nore clearly discernible near the distal end of the hinge line, the portion just back of the umbones appearing almost edentulous. The lower· posterior lateral is a little shorter than the 

upper one. Of cardinal teeth the only one preserved in the specimen at hand is one extending 

forwnrd from the beak, almost horizontal and fairly strong, very' siinilar to the anterior cn.rdinal of Ovrtodonta dunensis, :from the Lower Coblenzian fauna of Oberstadtfeld, near Daun, in 

the Eifel, figured by Drevennann. 4 Whether any other teeth are present can not be stated. 

I Clnrko, J. M., Tho Paleozoic faw1ns of Para, Brazil; Devonian Mollusca: Mus. nac. Hio do Janeiro Arch., vol. 10, pl. 6, figs. 14-16, 1899 

(author's l~ngllsh od., p. 51, 1900). 

B Hl\ll, Jl\mos, Paleontology of Now York, vol. 5, pt. 1, p. 355, pl. 53, figs. 21-26, 1885. 

a Idom, pp. 353-354. 

4 Po.laoontographica, v?l. 49, pl. 10, fig. 7'a,_1902. 
156 FAUNA OF THE CHAPMAN SANDSTONE OF MAINE.· 

Muscular scars and pallial line unknown. The surface appears to have been covered with 

obsolescent concentric strim of growth, .or was very nearly smooth. A few distant, son1ewhat 

stronger strim of growth or varices are apparent. No concentric ridges or radial markings. 

Length of type and only specimen 35 millimeters, height 24 millimeters, depth of single valve 

5 millimeters. · 

The fossil is easily recognized among the collections by the characteristic cyrtodontiforn1 

outline·. It is longer than high, and the length is less than twice the height. Shell widens 

posteriorly; anterior end narrow; ventral extremity at the posterior third; posterior margin 

semicircular; cardinal line straight, less than the height, and very slightly ascending; umbones 

between the anterior fourth and fifth; convexity moderate; strong ligamenta! groove; posterior laterals distant; surface smooth or tenuistriate, with a few distant varices. 

Locality: Moose River sandstone, Detroit, Somerset County, Maine (locality llOOA). Not 

in the Chapman fauna. 

U. S. National :Museum, catalogue No. 59780. 

Oomparisons.-This is one of the very few species in the Cypricardites group which lack 

the ventral insinuation below the beaks. The shell bears some relation to Ptychodesma knappianum Hall and Whitfield and has, like that species, the peculiar arching of the strim of the 

ligamental groove over the region· of the cardinal teeth. Oypricardites detroitense differs from 

the Ohio shell in having the anterior end much better developed, so that the beaks are not terminal. The front cardinal tooth is also more p.early horizontal rather than radial. Oyprica.rdites detroitense is very closely related to Modiomorpha sellowi Clarke,. previously referred to, . 

but the Maecuru shell is larger~ more nearly quadrate in outline, has a much wider anterior end 

and a consequently less rapid widening posteriorly, and the umbo is. a trifle more protruding. 

Clarke 1 shows, just in front of the beak, a nearly horizontal line which has some resemblance 

to the linear front cardinal tooth in Oypricardites detroitense. 

Superfamily NUCULACEA Dall. 

Families ?CTENODONTID.tE. Dall, NUCULID.tE Adams, and LEDID.tE Adams. 

The superfamily Nuculacea Dall 2 constitutes a natural evolutional group whose beginnings were in the early Paleozoic (the family " ~ Ctenodontidm Dall "), and from later Paleozoic 

to recent times the group has been represented by the two families Nuculidm and Ledidm of 

Adams. Verrill and Bush 3 group the Nucula-like shells in the two families Ledidm and Nuculidm and include the Paleozoic forms in a subfamily, Tindarina, 4 of the family Ledidm. These 

authors say of the family Ctenodontidm: 

Mr. Dall has proposed the family Ctenodontidm to inclufle the extinct genera above named [Palmoneilo, Nuculites] and others, but it is doubtful whether Ctenodonta itself belongs here. Zittel and others refer it to Arcidm. 

Dall 5 remarks that thi3 statement expresses complete n1is.conception of the arrangenwnt 

proposed by him and states, further, that he includes none of the members of Tindarinm Verrill 

in his group "Family ~Cte:p.o~ontidm." He continues: 

I have preferred to avoid attempting a revision of the Paleozoic genera, which comprise the beginning of so many 

groups and require for adequate comprehension a truly monographic treatment. 

Without proposing a solution of the difficulties in .the case I present the following notes, 

brought together in the process of distributing the species here described into appropriate generic groups, in the hope that they 1nay be useful to those who n1ay n1ake a serious attempt to 

treat .this group monographic'ally. 

1 Clarke, J. M., op. cit., fig. 14. 

2 Dall, W. H., Tertiary mollusks of Florida, pt. 3-A new classification of the Pelecypoda, etc.: Wagner Free Inst. Sci. 'frans., vol. 3, pt. 3, 

p. 515, 1895. . 

a Verrill, A. E., and Bush, K. J., Revision of the genera of Ledidre and Nuculidre of the Atlantic coast of the United States: Am. Jour. Sci., 

4th ser:, vol. 3, p. 51, 1897. 

4 Idem, p. 58. 

o Wagner Free Inst. Sci. Trans., vol. 3, pt. 4, p. 583, 1898. 
MOLLUSCA. 157 

Considerable discussion has ar11sen over the definition and proper application of the nan1es 

Tellinomya flail and Ctenodonta Salter, 1851, and to pave the way toward a proper generic 

classification some historical notice of these names becomes necessary. 

The genus Tellinomya was founded by Hal\1. in 1847 with the following diagnosis: 

Equiva.lvc, incquilatcral, somewhat compressed below but becoming gibbous at the umbones; umbo~es not angular; outline of the shell curved, without ::tngular ridges; shell thin, closely laminated; hinge without visible teeth 

crcnulations; muscular impressions two in each valve, near the dorsal margin; often apparently gaping at the postOriot· extremity. Type, T. nawta. 

Continuing, Ifall emphasized the difficulty of elucidating the real generic or hinge characters 

in such poorly and i1nperfectly preserved Paleozoic shells.. He pointed out that some· of these 

shells have, however, a characteristic form, saying: 

I am well aware of the difllculty, not to say impossibility, ·of properly characterizing a genus where the specimens 

are in the condition of these ancient fossils; and therefore general external form and the structure of the shell must be 

allowed some weight. In the present instance the form of the shell and some other characters in the typical series 

are so widely different that they can not fail to attract attention. 

At the twenty-first n1eeting of the ·British Association for the Advancement of Science, 

held at Ipswich in July, 1851: Logan 2 read a paper "On·the age of the copper-bearing rocks of 

Lakes Superior and fluron, and vnrious facts relating to the physical structure of Canada." To 

this paper, as published, Salter 3 added as an appendix a "Note on the fossil~ above mentioned, from the Ottawa River." The fossils referred to are fron1 the Trenton limestone at the 

southeast end of Allumette Island, on Ottlitwa River. Salter says: 

Among bivalve shells, which chiefly belong to the Arcacidoo, a very interesting new genus has rewarded examination. It was found that two species resembling Nucula in every general character differed .from it importantly by 

having no internal ligament, but a very manifest exterior one.4 One of these shells measures 3 inches across, and from 

the general analogy of several accompanyihg species it is believed that the genus will be found common in the Silurian rocks and will include many species now referred· to Nucula. It might be called Ctenodonta. 

No species are named, nor is any reference made to Nuculites Conrad or to Tellinomya Hall. 

In 1856 flail 5 noted the finding of good specimens, preserving the hinge, of six species of 

Tellinomya, n1ostly from the Trenton li1nestone of Ottawa River, and pointed out the error in 

his description of the hinge in 1847, which was drawn up from imperfect material. The hinge, 

according to flail's later description, shows a series of numerous small teeth or crenulations as 

in Nucula, but the teeth are continuous and not interrupted by a .cartilage pit, the ligament 

being external. Ifall, in this paper, .abandons the earlier rest.riction of Tellinomya to the characteristic fonn typified by the 1'. nasnta group and expands it to include all the Paleozoic shells 

with nuculoid dentition which differ from Nucula in lacking the cartilage pit, from Nuculites 

Conrad and Cuculella :McCoy in lacking the muscular clavicle or septum, and from Isoarca Miinster in not having the u1nbones spirally enrolled. Tellinomya as thus expanded is coextensive 

with Salter's Ctenodonta; flail, in f11:ct, mentions Ctenodonta Salter but does not give it any 

rank l-Ie states that the type species of Tellinon1ya I-Iall, 1847, T. nasnta, has a hinge identical 

with that proposed as characteristic of Ctenodonta Salter, 1851, and that the type species of 

Salter, ns ascertn,inecl by Ifall, is closely allied specifically to Tellinomya nas1.lta I-Iall. 

In 8:. P. Woodward's 1nanual of the Mollusca, first edition, Ctenodonta is given as a synonyn1 of Isoarca Mi.inster. 

In the first edition of l\1urehison's Silt1ria ·(1854) Salter does i1ot n1ention Ctenodonta, but 

uses Nucula for the Paleozoic taxodonts. 

In 1859 Salter 0 for the first time described and illustrated the n1aterial on which he founded 

his genus Ctenodonta. Ife stated/ with reference to Ctenodonta: 

I was not aware, when I proposed the above generic term for a group of Paleozoic N uculoo, that the principal 

species had been previously published under the name of Tellinomya by Hall * * * and if the name (Tellinomya) 

did not convey an entirely erroneous view of the affinities, I should be glad to restore it. 

1 Hall, James, Paleontology of New York, vol. 1, p. 151, 1847. 

2 Logan, W. E., British Assoc. Adv. Sci. 'l'wenty-first Meeting, Trans. Sections, pp. 59-62, 1852. 

s Salter, J. W., idem, pp. 63-65. . 

4 Mr. S. P. Woodward, of the British Museum, suggests that Solenella may contain these species. 

IS Hall, James, Canadi!l:n Naturalist and Geologist, vol. 1, pp. 39G-395, December, 1856. 

6 Murchison, R.I., Siluria, 3d cd., pp. 213, 859, 1859. 

1 Salter, J. W., Figurm: and descriptions of Canadian organic remains, decade 1, p. 34, 1859. 
158 FAUNA OF THE CHAPMAN SANDSTONE OF MAINE. 

Salter gives, as an additional reason for retaining Ctenodonta Salter, 1851, in preference 

to Tellinomya Hall, 1847, the fact that the essential feature of the shells, the ligament and 

hinge teeth, was overlooked and misrepresented in IIall's original diagnosis of Tellinon1ya in 

1847. However, Salter does not mention in this connection the fact that not a single species 

of Ctenodonta had been described or figured or really known to anyone except Salter himself 

prior to 1859, whereas Tellinomya was sufficiently corrected and revised and well figured and 

described by I-Iall in 1856. 

The Gtenodonta logani of Salter, which had appeared by name without specific description 

or illustration in Woodward's "Manual," and which was regarded as the type of Ctenodonta, 

was shown by Hall and by Salter to be identical with Tellinomya nasuta Hall. A new cOinplication thus arose, both Tellinomya and Ctenodonta being founded on the same species, as 

Salter fully admitted. Salter described, in addition to Gtenodonta nasuta, two closely allied 

species-G. logani Salter, 1859 olim (T. dubia Hall, pars), and G. contracta Salter-as well as 

two other species-G. gibberula (genus Glyptarca Beushausen, s. str.) and G. astartrejormis 

(genus Ctenodonta Salter, emend. s. str.). 

The principal arguments against the use of Tellinomya are these: (1) The name Tellinomya proposed by Hall in 1847 may be regarded as preoccupied, having been suggested by 

Agassiz in 1846 as the corrected orthography of Tellimya Brown, 1827. (2) The description 

of the genus Tellinomya Hall, 1847, was imperfect and misleading with regard to _the essential 

feature, the· hinge characters. (3) The name conveys a suggestion of relationship which is 

erroneous when the hinge is considered. 

The name Ctenodonta, however, was proposed in 1851 (published 1852), over four years 

later than the publication of Tellinomya Hall, 1847. Moreover, if the description of Telll.nomya 

Hall, 1847, is· regarded as invalid, the fact still remains· that Tellinomya was completely 

described and illustrated by Hall in 1856, whereas not a single species of Ctenodonta was 

known by name or specifically referable to Ctenodonta before 1859, except the nude specific 

name Otenodonta logani, which appeared in Woodward's "Manual." Again, the type species 

of Ctenodonta, G. logani Salter, is identical with the type species of Tellinomya, and Salter 

himself united his types with Hall's species Tellinomya nasuta and accepted Hall's specific 

name, but refused to accept Hall's generic name Tellinomya, calling his shells Otenodonta nasuta 

(I-Iall). 

As will be more fully shown, both Tellinomya and Ctenodonta ought to be retained. The 

principal argument against the name Tellinomya Hall is, of course, its supposed preoccupancy. 

The genus Tellimya was founded by Brown in 1827 for some different bivalve shells. In 1846 

Agassiz undertook in his "N omenclator zoologicus" to correct the name to Tellinomya on· the 

assumption that, based on Tellina and Mya, the spelling Tellimya was improper, Tellinomya 

being the correct form. Agassiz did not propose a new genus or a new generic name, but 

n1erely corrected the orthography of Tellimya Brown. I am not aware of any definite rule on 

this point, but modern usage among biologists appears to tend to the preservation of the oi·iginal 

orthography of a generic name, provided, of course, the name is Latin or latinized. It is 

obvious that endless confusion would result if each biologist were allowed to alter a name 

according to what he thought to be the proper orthography. In1agine the chaos, to put it 

mildly, if the same organism might be called· Arthroacantha, Arthroacanthia, Arthroacanthus, 

Arthracantha, Arthrocanthus, or Arthracanthus, according to different persons' ideas of correct 

orthography; or take Aviculopecten, Aviculipecten, Aviculapecten, Avicuhepecten; or Pachyrisma, Pachyorisma, Pachyerisma; or Paleoneilo, Palreoneilo, Palreaneilo, Paleaneilo; or 

Tellimya, Tellomya, Tellinamya, Tellinremya, Tellinomya, Tellinin1ya; or, finally, suppose the 

individual caprice for correct orthography should cause someone to change a commonly accepted 

name like Allorisma to Allerisma, at the same time stating that Allreerisma is really the proper 

form but is "unbeautiful ,and impractical!" Manifestly Tellimya Brown, 1827, even if 

'derived from Tellina and Mya, is as beautiful and, it might even be argued, technically as 

correct as Tellinomya Agassiz, 1846; moreover, it has the further advantage of being brief and 

practical, in addition to being the original name. Besides, not having seen Brown's work and 
MOLLUSCA. 159 

not actually knowing that Brown really did fonn Tellimya from Tellina and Mya., I might 

argue, as do :Miller and Faber, 1 that Tellimya Inight have been derived from the Greek word 

rdAw and Mya, Ineaning ''dawn of Mya," or possibly Brown may have prefixed to Mya. the 

na1ne of a n1an called Tell, producing a name analogous with Barrandeoceras, Agassizodus, 

Collettosaurus, l\1illericrinus, and 1iV orthenopora. Agassiz's work, being n1erely a nondescriptive catalogue, has no effect in fixing priority in nomenclature, and as a matter of fact his 

Iuune Tellinomya has never been used by conchologists. Fischer in his ''Manual" considers 

Teli.imya a. synonym of Montacuta, but more recently Brown's genus has been separated, a.nd 

n1oder.n authors 2 use the word Tellimya in its original form. Tellinomya Agassiz, 1846, must 

therefore be expunged fron1 non1enclature as a dead word, and the argument that its use causes 

'l"ellinomya 1-Iall, 1.84 7, to be preoccupied therefore falls to the ground. · 

The second argument against Tellinomya is that the description of Tellinomya in 184 7 

was imperfect and misleading with regard to the essential hinge features; but the genus was 

fully redescribed and corrected (and incidentally expanded by I-Iall) in 1856. Even without this 

redefinition the peculiar forn1 of the nasuta group, which was chu.racterized as being diagnostic 

of the genus, is sufficiently pronounced to permit Tellinomya to stand on external features. 

The third argun1ent against Tellinoniyu., that the name conveys an erroneous suggestion of 

the a:fftnities of the fossil, even if true, would have no value according to modern usage. As a 

n1atter of fact, however, the genus Tellinomya ought to be returned to its original lin1its to 

include only the T. nasuta group, and for this group the name is eminently fitting in that the 

forrn really does recall Tellina and Mya. 

The nan1e Ctenodonta in the strict sense would be a synonym of Tellinomya, but in the 

expanded usa.ge of Ctenodonta adopted by Salter and other authors var~ous heterogeneric 

species were included. The first of these species desctibed and figured, Ctenodonta astartcejormis 

Salter, is reu.dily separable from Tellinomya nasuta and its allies and is capable of standing as a 

nucleus of a separate genus. 

]~xpansion of Tellinmnya or Ctenodon ta to include under o:o.e ·name or the other all the 

Paleozoic and early Mesozoic nuculoids devoid of cartilage pit seems inappropriate, for if all 

these shells are to be included under one generic name the earlier and well-known name Isoarca 

l\1rmster, 1842, n1ight be adopted il.S was done in Woodward's "l\1anual," and more recently by 

Tate.8 Indeed, the still earlier nan1e Nuculites Conrad, 1841, might be adopted, for Conrad 

recognized the in1portance in these nuculoid shells of the absence of a cartilage pit and the uninterrupted continuu.tion of the teeth beneath the beaks. 

The species of N uculacea discovered in the Chu.pman fauna are placed in the following genera: 

Cleidophorus 1-Iall, Myoplusia Neumayr, Tellinites McCoy, and Paleoneilo ~all. 

G~enus CLEIDOPHORUS Hall. 

The genus Cleiclophorus was founded by Hall 4 in 1847 for J.Vuculites planulata Conrad, of 

the Upper Ordovician. The genus was supposed to be characterized, like Conrad1s genus 

Nuculites, by the developn1ent of a persistent, conspicuous, anterior ·muscular septum, but 

I-Iall did not observe any hinge crenulations. However, in all the shells of this type where the 

hinge structure has been observed the hinge is taxodontic, as in Nuculites. The generic name 

Cucullella was applied by McCoy 5 four years later for the same group of shells as represented 

in Great Britain, where the hinge crenulations were observed. 

Speciinens of Oleidophorus pl<tnulatus (Conrad) are rather uncommon, so that taxodontic 

dentition in this species can not be absolutely demonstrated. The strongest evidence in favor 

of assu1ning taxodontic dentition in the type species of Cleidophorus is the fact that the species 

t Miller, S. A., and Faber, C. L., Cincinnati Soc. Nat. Hist. Jour., vol. 17, pp. 149-151, 1894. 

2 'l'he eminent British conchologist, E. A. Smith (On a collection of mo.dne shells from Port Alfred, Cape Colony: Jour. 1\Ialacology, vol. 11, 

p. 41, London, 1904), describes o.nd figures o. bivo.lve shell as Tcllimya similis. 

u To.te, Hal ph, l~osslls of the JJo.mpintino series (Ordovician): Report on the work of the Hom scientific expedition to centml Austmlia, vol. 3, 

Ooolo~y o.nd botany, pp. 97-116, 3 pis., London o.nd Melbourne, March, 1896. 

4 Hoi!, James, Paleontology of New York, vol. 1, p. 300, 1847. 

n McCoy, Frederick, Anno.ls o.nd Mag. Nat. Hist., 2d ser., vol. 7, p. 50, 1851. 
160 FAUNA OF THE CHAPMAN SANDSTONE OF MAINE. 

was included in the taxodont genus Nuculites bJ Conrad in his original diagnosis in 1841, and 

the other eight of the nine species of ."Nuculites" there described by Conrad are taxodontic. 

In the second place, as has already been pointed out, \vhenever the hinge of sin1ilar Paleozoic 

shells. has been exposed to view it has revealed a taxodontic dentition. In this connection 

it may be no.ted that the taxodont Tellinomya was likewise originally described by I-Iall (in 

the same work in which Cleidophorus was described) as being devoid of hinge crenulations. 

The taxodont Cucullella therefore appears to be strictly synonyn1ous with the imperfectly 

described Cleidophorus, but comparison of the shells of the group of Oleido1Jhorus planulatus 

with typic'11 Nuculit~s triqueter shows a ready and i~portant distinction. In Nuculites triqueter 

and several other species, to which the name Nuculites ought to be restricted, there is a welldeveloped posterior ridge which seems to have been associated with a well-developed siphon 

or anal tube in the animal. This significance of the posterior ridge is suggested by the fact 

that some specimens of Nuculites triqueter Conrad and the similar Silurian 1V. coarctata Phillips 

become emarginate, as in Paleoneilo, Koenenia, and Tellinites (Tellinopsis). In the typical 

Ordovician and Silurian, as well as in most Devonian forms to which the name Cleidophorus 

ought to be applied, the surface is smoothly oval without trace of any· definablepostun1bonal 

ridge .. If I am correct, in associating the development of a postumbonal ridge in Nuculites 

s. str. with the occurrence of a well-developed siphon or anal tube, then the persistent absence 

of such a ridge in a large number ·of widely distributed species deserves some notice; and for 

.such oval forms devoid of postumbonal ridge the name Cleidophorus Hall n1aJ well be retained. 

CLEIDOPHORUS CURTUS sp. nov. 

Plate XIX, figure 1. 

Small, moderately convex shells of :transversely ovate outline, widest in front, tapering 

behind. Proportion of height to length, .7 :10. Greatest height at the 1nidlength ·or just in 

front; greatest length at tl;le inferior two-fifths. Beaks inconspicuous, not protruding above 

the hinge line; situated at the anterior two-fifths or third; slightly prosogyrate, nearly vertical. 

The anterior end is high and SJmmetrically rounded, with the forward extremity at the nlidheight rounding into the ventral1nargin, which is symmetrically bellied down; ventral extremity 

at the 1nidlength. The postventral "angle" is rounded, obscurely discernible; between this 

and a distinct hinge extremity is demarcated a posterior margin which is retrorse and equal 

in length to half the height of the shell. The posterior extremity is just above the postventral 

"angle," at the inferior third of t4e height of the shell. The hinge extremity is obtusely subangular. The hinge line is declining, faintlJ convex, nearly straight, and slightly longer than 

half the height of the shell. The valves are evenly rounded throughout except that below the 

hinge line the surface is more nearly plane, though highly inclined. The point of maximun1 

depth is a trifle above the middle of the shell. There is neither a postumbonal nor a preumbonal 

ridge, nor any trace of the posterior sinus. The depth of the single valve is equal to a little 

more than one-fourth, perhaps one-third the height. Ligament and teeth unknown. Muscular 

scars moderately in1pressed, each strongly delineated on its umbonal side by a curved septal 

ridge. The septum bounding the anterior scar extends from a poi.nt in1mediately in front of 

the umbo downward and forward about to the midheight. The posterior septu~ is blunter 

and n1ore oblique than that bounding the anterior scar. The muscular scars are of about equal 

size and their distal margins are indistinct. No umbonal scars were observed. Pallial line 

not observed. Shell thin, except where thickened on the interior by the septal ridges. 

The internal mold is smooth, and fragments of the surface also appear smooth, disclosing 

under a hand magnifier, however, extremely fine, tenuous lines of growth. Length 10 millimeters, width 7 millimeters. · 

Locality: The type arid only specimen· is a left valve fron1 the Chapman. sandstone of 

Edmunds Hill, Chapman Township, Aroostook County, Maine. 

U. S. National Museum, catalogue No. 59768. 

The species is distinguished from the other Cleidophori by the occurrence of two n1uscular 

septa, the nearly central position of the beaks, the subangular hinge extremity, and the high 
MOLLUSCA. 161 

form, the height being equal to seven-tenths the length. The posterior margin is nearly equal 

to the length of the hinge line. 

OomzJarisons.-The fossil has almost precisely the size, shape, and outline of Nucula 

(Nuculites s. str.) coarctata Phillips/ but Phillips's species has a well-developed posterior ridge 

(sometin1es accompanied, as in a few rare specimens of Nuculites triqueter, by an emargination 

and sinus), which places it in t;he genus Nuculites. N. coarctata also lacks the posterior septun1. 

OleidozJhorus curtus also resembles the short forms of the N eo-Ordovician OleidophoTus 

(Nuculites) neglectus I-Iall figured by IDrich, 2 but the latter are distinguished by having the 

muscular septum longer and vertical, and by having a faint postumbonal ridge. 

·CLEIDOPHORUS PEROVALIS sp. nov. · 

Plate XXV, figures 2, 10. 

A second species of Cleidophorus is represented in the Chapman collections by a couple 

of specimens fro1n Ed1nunds Hill (locality 1099 M:). The form is of the smoothly rounded, 

subsynunetricuJly oval type of Cleidophorus characteristic of most of the Ordovician, Silurian, 

and early Devonian species of thn genus. Outline transversely oval, margin nearly syminetrically rounded; proportion of height to length, 3:5. Greatest height at the n1idlength; greatest 

length at the 1nidheight. U1nbones inconspicuous, sn1all, depressed to the hinge line; directed 

forward, and situated at the anterior fourth of the length. Anterior end short, though fairly 

high; forward extremity at the midheight, the 1nargin rounding into the ventral1nargin, which 

is a synnnetrical, strongly bellied-down arch, ascending markedly to the ill-defined respiratory 

(postventral) angle. 'The posterior 1nargin is similar to the anterior, and rounds into the hinge 

line, which is gently convex, horizontal to a point just back of the 1nidlength of the shell, thence 

descending and ,rounding into the posterior n1argin. The dorsal a~1d ventral extre1nities are 

both at the 1nidlength. The surface is sn1oothly and evenly rounded throughout, except near 

the postdorsal region, where there is a narrow, somewhat flattened strip. The shell is of nwderate convexity, and the depth of the sipgle valve is equal to about one-fourth its height. The 

point of greatest depth is at the anterior two-fifths of the length and at, or onl)r slightly above, 

the 1nidheight. Ligamenta! strueture and teeth unknown. :Muscular scn,rs not i1npressed. 

1'here is no posterior n1uscular septun1 or ridge. The anterior septun1 is very narrow and thin; 

fro.m a point i1nn1edin.tely in front of the un1bo it ·extends downward, slightly backward fro1n 

the verticn.l, to the inferior third of the height of the shell. 

1'he sculpture casts are nearly s1nooth, but show very faint tenuistriate lines of growth. 

The type speci1nen, a right valve, has a length of 21 Inilliineters, a height of 12.75 1nillimeters, 

and a depth of 3 1nillin1eters. A second frag1nent, vertically c01npressed, is 22 n1illi1neters 

long and 12.5 Inilliineters high. · 

Locn.lity: Chn.p1nan sn.ndstone, west side of Edmunds Hill, Chapman Township,.Aroostook 

County, J\1aine. 

U. S. National J\1useuin, catalogue No. 59769. 

Oomparisort~·.--The species closely rese1nbles the large uniseptate species of Cleidophorus 

described and figured by Beushausen 3 as Oucullella elliptica J\1aurer, but is more sym1netricn.l, 

tapers less posteriorly, and, unlike the Oerman shell, which is described as being strongly 

inflated, is only nloderately convex. 

J.Vuculites branneri Cln,rke, 4 fro1n t}le Brazilian Lower Coblenzian fauna of Rio :Maecuru, 

is sotnewhat si1nilar, but has 1nore protuberant and conspicuous un1bones, a lower anterior end, 

and the dorsal1nargin n1ore rapidly descending fro1n the beaks, with the uppermost extremity 

of the shell in advn.nce of the 1nidllength. 

. ' 1 Goo!. Survey Grel\t Britl\in Mom., vol. 2, pt. 1, p. 366, pl. 22, figs. 2, 3 (not figs. 1, 4), 1848; British Upper Ludlow-Downtonian sandstones 

of Freshwater Bay. 2 Geology or Minnesota, vol. 3, pt. 2 (Paleontology), pl., figs. 20-23 (not fig. 25, which represents the elongate form), 1894. 

s Beushausen, IJouis, Die Lamcllibranchiaten des rheinischen Devon: K. preuss. geol. Landesanstalt Abh., new ser., vol. 17, p. 104, pl. 5 (pars), 

figs. !l, 10, 11 (not figs. 12-15), 1895. Lower CoblenziEm of Nellenkopfchen, Rhenish Prussia. 

4 Clarke, J. l\f., 'l'he Paleozoic faunas of Para, Brazil, pt. 2, Devonian Mollusca: Mus. nac. Rio de Janeiro Arch., vol. 10, pl. 8, figs. 6-8, 18!)!) 

(author's English ed., p. 73, 1!l00). 

50245°--~o.89--16----ll 
162 FAUNA OF THE CHAPMAN SANDSTONE OF MAINE. 

The Silurian Oleidophorus brasilianus Clarke 1 is also similar, but has more protrudi;ng 

umbones, and tapers more posteriorly. 

Oleidophorus perovalis sp. nov. is very similar to the transversely oval· Ordovician shell 

figured and described by Ulrich 2 as Oleidophorus neglectus Hall, but differs from the Ordovician 

species in having a proportionately greater height and in being more gibbous. 

Genus MYOPLUSIA Neumayr, 1883·. 

The ctenodontoid shells to which Neumayr applied the generic narne Myoplusia are transversely elongated, with a high but short rounded anterior end and a-lower, rnore elongated, and 

tapering posterior end; beaks directed forward; outline entire, ;not emarginate; without posterior surface sinus and ridge. 

Myoplusia was actually founded on the character of the muscular scars, but the name 

may be applied, pending a thorough revision of these Paleozoic shells, to the type of outline 

described above. This outline ~s typically expressed in "Paleoneilo'' sulcatina (Conrad) 3 and 

similar rionemarginate shells. Myoplusia appears to be most nearly related to the transversely 

elongate Paleoneilos of the " 'Otenodonta' dalleidense Beushausen group." These transversely 

elongated Paleoneilos have essentially the outline of Myoplusia described above, but have a 

more or less faint sinus or emargination postventrally. In some specimens of a few such species 

of Paleoneilo the postventral emargination becomes obsolescent, and such specimens appear to 

conform with Myoplusia. Myoplusia, however, represents persistently nonemarginate shells. 

MYOPLUSIA CHAPMAN! sp. nov. 

Plate XXV, figure 7. 

A small, incomplete, fractured specimen of a Myoplusia occurs in the Chapman sandstone 

on Presque Isle Stream. The shell does not appear to belong to any known species. Because 

of ·the imperfection of the type specimen it is with reluctance that I apply to it a specific nan1e. 

Length, 10 millimeters; height, 6~ millimeters. Greatest length at about the n1idheight; 

greatest height in front of the middle. Beaks slightly protruding, prosogyrate, situated at the 

anterior fifth or sixth. Anterior end short but fairly high. A faint lunule is developed in 

front of the beaks, where the anterior margin is abruptly curved downward, rounding into 

the strongly arched ventral margin. Ventral extremity at the midlength. Posterior end 

tapering, elliptically rounded; no definable postventral extremity nor hinge extrmnity nor 

posterior margip.. Hinge line gently convex, ascending from the rear to the umbones, with 

the highest point at the anterio~ fourth. Shell strongly convex; inflated below the umbones, 

which are incurved to the hinge line. The surface is evenly rounded, except for the concave 

lunule in front of the beaks. The depth of· the single valve is equal to about half the height; 

the point of greatest depth is situated near the midheight, a trifle in advance of the rniddle. 

Hinge unknown. Muscular scars not impressed. 

· To judge from the internal mold, which is in part a faint "sculpture cast," the shell may 

have been marked with tenuistriate lines of growth, or nearly smooth.· 

Locality: Chapman sandstone, Presque Isle Stream, at t~1e end of the Tweedy road (locality· 

1099 A), Chapman Township, Aroostook County, Maine. 

U.S. National Museum, catalogue No. 59770. 

Oomparisons.-The species closely resembles "Otenodonta" krotonis· Roemer as figured by 

Beushausen, 4 but the German species is lower and has the muscular .scars more strongly 

impressed. 

1 Clarke, J. M., The Paleozoic faunas of Para, Brazil, pt. 1, The Silurian faunas of the Rio Trombetas: Mus. nac. Rio de·Janeiro Arch., vol. 10, 

p. 18, pl. 2, figs. 17-19, 1899 (author's English ed., 1900). 

2 Ulrich, E. 0., The Lower Silurian Lamellibranchiata of Minnesota: Geology of Minnesota, vol. 2, pt. 2 (Paleontology), p. 607, pl. 42, fig. 25 

(not figs. 20-24) 1894, "Nucula beds" of the Maquoketa shale, Graf, Iowa. 

a See Paleontology of New York, vol. 5, pt. 1, p. 347, pl. 50, figs. 42, 44-46 (not fig. 43, which is a Paleoneilo of the P. truncata type), 1885. 

4 Beushausen, Louis, DieLamellibranchiaten des Rheinischen Devon: K. preuss. geol. Landesanstalt Abh., new ser., vol. 17, p. 72, pl. 5, 

figs. 24, 25, 1895; Wissenbach shales (lower Meso-Devonian). 
MOLLUSCA. 163 

"Otenodonta/' primreva (Steininger)/ which also possesses the Myoplusia outline, is a much 

larger shell find has a shallower ventral margin. 

In size and o~tline Myoplusia chapmani approaches most closely a little Coblenzian specimen identified by Beushausen 2 with Oleidophorus ellipticus (Maurer). 

Genus TELLINITES McCoy (KOENENIA Beushausen). 

I(oenenia s. str.: Beaks decidledly prosogyrate and usually situated well forward. A 

single posterior sinus is well developed and is commonly marked on one or both sides by a 

strong fold. Occurs in the Devonian and Carboniferous of Europe and America. The subgroup Bicrenula nov. is like Koenenia, but the surface strire· on the postetior slope form two 

nen,t reentrant arches. Types: Paleoneilo bisulcata Hall and P. ang'Lf,sta Hall, from the 

Che1nung for1nation, New York; P. muricata Clarke, from the lower part of the Portage 

("Nunda") formation, New York. 

'rellinites s. str.: Umbones subcentral or central, directed vertically or only slightly 

prosogyrate; posterior sinus shallow, developed more or less faintly and variably, and acconlpanied in son1e specimens by one or two rounded obsolescent radial folds. Ordovician (Bohemia), Silurian (Great Britain), Eo-Devonian (Europe, South Africa, South America, and 

North America), and Meso-Devonian (North and South America). 

'fellinopsis IInll: Like Tellinites McCoy, but showing traces of a forward sinus also. 

T. S'l.tbemm·ginatus (Conrad), I-Iamilton fauna, New York. 

The above represent the principal subgroups under Tellinites. Each is capable of subdivision. 

As the old tenn Paleoneilo Hall, formerly applied to these and similar shells, manifestly like 

Tellinomya, requires restriction, it has been deemed proper to restrict Paleoneilo to the forms 

closely resen1bling the genotype, P . . constricta (Conrad). Hall included in Paleoneilo shells 

which ought to be separated chiefly into the groups of Verrillella, Koenenia, Tellinites, Myoplusia, and Tellinomya. • 

The ~enus Tellinites was founded in 1851 by McCoy 3 for T. affinis McCoy, from the Upper 

Ludlow of Kendal, Westmoreland. The peculiar outline was the essential characteristic of 

the genus, the hinge line being unknown. From their characteristic outline and evident similarity to '' Otenodonta '' elegans Mau:rer, '' Palreoneilo '' 1Jerplana Hall, '' Palreoneilo '' virginica 

I-Ia.U., etc., which are lmown to be taxodontic, it may reasonably be assumed that Tellinites 

McCoy n,nd Tellinopsis I-Iall, are taxodontic, and the name Tellinites McCoy may be applied 

to the group under discussion. 

Tellinites (~ffinis McCoy and T. elegans (Maurer), with the two Chapman species here described, T. cha,pm(tni and T. curta, form with their transverse rounded outline and faint sinus a 

well-marked group easily distinguishable f~om the more quadrat~ Tellinopsis I-Iall, which lias 

a stronger sinus and fold. In Tellino1Jsis subemarginata also there is, occasionally, an anterior 

emai·gination, suggesting a well-developed anterior siphon. T. gibbosa Goldfuss, T. 'l.tnioniformis Sandberger, T. orbignyi Clarke, and some of the Chapman shells present a closer analogy 

with Tellinopsis than with typical Tellinites; and the Paleoneilo snlcata of Hartt and Rathbun 

"represents a type intennediate between these and typical Koenenia. The various groups in 

Tellinites senso lato semn to grade into one another, or at least they appear to be connected 

by several inte1~mediate types. 

TELLINITES CHAPMAN! sp. nov. 

Plate XIX, figure 5. 

This name is applied to a typical Tellinites of the group of· the Upper Ludlow T. affinis 

McCoy, the·genotype of Tellinites. 

I-Ieight, 0.57 the length in the type specimen; greatest height at the midlength; greatest 

length below the middle, near the inferior third or .two-fifths. Umbones broad; vertical, or 

1 Boushanscn, J_,ouls, Dlo J..amollibranchiaten des Rlb.olnlschen Devon: K. preuss. geol. Landesantalt Abh., new ser., vol. 17, p. 72, pl. 

5, flg. 13. Wlssonbach shales (lower Meso-Devonian). 

u ldom, pl. 5, figs. 28-30. 

s McCoy, Frodcrlck, Annals and Mag. Nat. Hist., 2d ser., vol. 7, p. 51,1851. See also Sedgwick, Adam, and McCoy, Frederick, British Paleozoic 

rocks and fossils, p. 286, pl. I K, fig. 31, 1852. 
164 FAUNA OF THE CHAPMAN SANDSTONE OF MAINE. 

extremely faintly prosogyrate; not protruding above the hinge; situated only slightly in advance 

of the midlength, at the anterior 0.45. Anterior end large; as high. and nearly but not quite as 

long as the posterior end. The margin of the anterior end ·of the shell make$ a deep, symmetrical paraboloid arch, with the forward extremity at the n1idheight. Ventral margin shallow,. 

nearly straight, constricted in the middle .by the unde£0_-ed sinus; thence strongly ascending to 

the rounded postventral angle. The posterior margin is· retrorse, slightly arcuate, and devoid 

of insinuation; it is equal in length to two-thirds the height of the shell. The hinge extremity 

is obtusely sub angular. The hinge line is depressed-convex, nearly straight; it descends to the 

rear, and is only slightly longer than the posterior margin. The shell is moderately ventricose; 

the body of the va1ve is broadly inflated below the umbones. The greatest depth is equal to 

a little over one-third the height in each valve. The point of maximum depth is situated near 

the midheight at the upper third of the height. There is discernible on the surface in our 

specimens an exceedingly faint radial sinus or flattening extending below the umbones at a 

very small angle backward from the vertical. In front of the region of the post-umbonal ridge 

is a second obsolescent flattening, narrower and much fainter than the first and extending backward at an angle of approxima-tely 45°. The umbonal ridge is undefined; the posterior slope 

is very steep, and devoid of insinuation. Ligament and dentition unknown. Muscular scars 

not impressed on the shell, and not discernible on ·the specimen which is a clean internal m9ld. 

Shell decidedly thin, almost papery. 

The surface ornamentation consists of very fine concentric lines and strirn of growth, interrupted about every millimeter, more or less, by a lit.tle stronger stria of "growth" (rest), producing faint little concentric ·undulations. These are developed a· little n1ore prominently on 

the forward part. The type specimen, a single right valve in clean internal mold, is 37 nlillimeters long, 21 millimeters high, and 7.5 millimeters deep. 

The distinguishing features of this shell are the broadly oval form, with height less than 

three-fifths the length; beaks nearly central (at the anterior 0.45), broad, vertical, incurved 

to the hinge line; anterior end as high and nearly as long as the posterior end; ventral margin 

shallowly convex, constricted near the middle; posterior margin well defined and devoid of 

insinuation; shell moderately ventricose and apparently devoid of surface sinus, except that a 

faint flattening extends nearly vertically behind the beaks, and a second narrower and exceedingly faint flattening occurs in front of the undefined posterior ridge. ' 

Locality: Chapman sandstone, 2 miles west of Presque Isle Stream, Chapman Township, 

Aroostook County, Maine. 

U.S. National Museum, catalogue No. 59771. 

Oomparisons.-In the broadly oval form, strong convexity, subcentral position of the 

vertebral beaks, and faint character as well as the position of the posterior sinuses the species 

is a typical member of the group of Tellinites ajjinis McCoy/ fro1n the British Upper Ludlow, 

the genotype of Tellinit.es. I was, indeed, origii1ally inclined to unite the Chapman specimen. 

with McCoy's species, and subsequent larger collections may possibly prove that the]' are the 

same. In the Chapman specimen, however, the height is more than half the length (0.57 the 

lerigth, as compared with 0.45 for McCoy's shell), the .beaks are a trifle farther forward, and . 

the posterior sinus is slightly weaker. 

The Chapman shell also bears a close similarity to the Rhenish Tellinites elegans (Maurer), 

figured as Otenodonta elegans by Beushausen. 2 The German Eo-Devonian shell is flatter and 

proportionately higher than either T. ajjinis or T. chapmaniJ· no n1ention is made in the text, 

nor is any indication given in the figure, of the subcentral constriction or sinus of the ventral 

margm. 

1 McCoy, Frederick, in Sedgwick and McCoy, British Paleozoic rocks and fossils, p. 286, pl. 1K, fig. 31, 1852; Upper Ludlow•of Benson Knot, 

Kendal, Westmoreland. . . 

2 Beushausen, Louis, Die Lamellibranchiaten de·s rheinischen Devon: K. preuss." geol. Landesanstalt Abh., new ser., vol.17, p. 81, pl. 7, figs. 6, 7, 

1895. Beushausen records the species from the Lower Coblenzian of Nellenkopfchen, in Rhenish Prussia. 
MOLLUSCA. 165 

TELLINITES CURTA sp. nov. 

Plate XXV, figure 14. 

Shell moderately large, broadly oval, nearly equilateral. I-Ieight 0.65 the length. Position of greatest height and greatest length and character of umbones, anterior end, ventral, posterior, and hinge 1nargins, etc., ns in T. chapmani. :Moderately ventricose; broadly inflated 

below the un1bones; point of greatest depth directly below the u1nbones, slightly above the 

1nidheight. Depth of the single valve very nearly equal to a third of the height. Subcentral 

sinus and posterior sinus essentitJly as in T. chapmani. The second or narrower sinus in T. 

cu?·tCL is exceedingly faint. Its position is indicated by two obsolescent radial strire or lines 

which 1nay be discernible when orienting the specin1en at varying angles to the light. A similar 

structure is noted in T. chapmani,' and Beushausen 1 also records in Tellinites elegans (Maurer) 

two such "very delicate rn,dialli11es, becoming visible only with changing light." The occurrence of these d,elicate radial lines on the interior of the shell supports the theory associating 

the developn1ent of a posterior sinus in these Paleozoic taxodonts with a well-developed special 

internal organ, such as a posterior siphon or anal tube. Muscular scars, as in T. chapmani, not 

impressed.· Shell thin, nearly pn.pery. 

Surface ornamentation as in T. chapmani, except that it is a trifle less strongly marked. 

' Length 29.5 millin1eters, height 19 n1illimeters, depth of the single right valve 5.75 D;lillimeters. 

Unfortunately only a single specimen each of T. curta and T. chapmani is known. These 

two specime~s n1ay possibly represent varieties or individual differences of one and the same 

species. T. cu1·ta is distinguishable from T.· chapmani by its higher, less transversely elongated 

fol'ln. 

Locality: Chapman sandstone, west side of Edmunds I-Iill, Chap1nan Township, Aroostook 

County, Maine. · 

U.S. National Museum, catalogue No. 59772. 

TELLINITES (KOENENIA) GIBBOSA Goldfuss var. KAYSERI Beushausen. 

Plate XIX, figures 3, 9, 11, 13, 15, 16; Plate XXV, figures 1, 3, 4, 5, 12. 

var. CRASSA Beushausen. 

Plate XXV, figure 8. 

1834,..-1840. Sanguinolaria gibbosa. Goldfuss, Petrefactre Germanire, vol. 2, p. 278, pl. 159, :fig. 10 (figure bad; see 

Beushausen, 1895). 

[Siegen] clay shales: Altenah.r, Germany. 

1850-1856. N'l.te'l.tla 'l.tnionijonnis. Sandberger, Versteinerungen des rheinischen Schichtensystems in Nassau, p. 277, 

pl. 29, fig. 1. . 

Lowest Coblenzian graywacke: Singhofen, Germany. 

1884. Palmoneilo neglecta. Beushausen, Fauna des Oberharzer Spiriferensandsteins, etc., p. 77, pl. 4, fig. 22. 

Spirifer sandstone (Coblenzian): Bocks berg, Harz Mountains, Germany. 

1884. Palmoneilo occulta. Beushausen, idem, p. 78, pl. 4, fig. 25. 

Spirifer sandstone (Coblenzian): Bocksberg, Harz Mountains, Germany. 

1895. Ctenodonta (Palmoneilo) crassa (pars). Beushausen, Lamellibranchiaten des rheinischen Devon, p. 77, pl. 6, 

fig. 5 (not fig. 4). · 

Coblenz (Ems) quartzite: Rhens, Germany. 

1895. Cte~donta (Palmoneilo) ka.yseri: (pars). Beushausen, idem, p. 82, pl. 19 (except fig. 18). 

J.,ower Coblenzian: St. Johann a. Kyll, Germany. 

1895. Ctenodonta (Palmoneilo) gibbosa. Beushausen, idem, p. 83, pl. 6, fig. 16. 

Siegen graywacke: Saxler, near Gillenfeld, Siegen district, and Altenahr, Germany. 

1895. Ctenodonta (Palmoneilo) 'l.tnionifomtis. Beushausen, idl3m, p. 84, pl. 6, figs. 10-15, except fig. 14. 

]~ower Coblenzian: St. Johann a. Kyll; Gemund, near Daun, in the Eifel; Nellenkopfchen; Singhofen, Germany. 

1899. Palmoneilo orbignyi. Clarke, Mus. nac. Rio de Janeiro Arch., vol. 10, pl. 8, figs. 14,....17 (English ed., p. 74, 1900). 

Devonian [Lower Coblenzian]: Rio Maecuru, Para, Brazil. 

1902., Ctenodonta (Palmoneilo) kayseri and wnionijormis. Drevermann, Palaeontographica, vol. 49, p. 87. 

]~ower Coblenzian: Oberstaclt.felcl, near D.aun, in the Eifel, Germany. 

1 Op. cit., p. 81. 
166 FAUNA OF THE CHAPMAN SANDSTONE OF MAINE. 

1904. Ctenodonta (Palreoneilo) gibbosa (?). Drevermann, Palaeontographica, vol. 50, p. 243. 

Siegen graywacke: Seifen, near Dierdorf, in the Westerwald, Germany. 

cf. 1906. Palce.oneilo boyesei. Schwarz, Albany (South Africa) Mus. Rec., vol. 1, pt. 4, p. 377, pl. 8, fig. 4. 

[Lower Coblenzian] shale: Hottentots Kloof and Vitkomst, South Africa. 

1907. Paleoneilo circulus. Clarke, New York State Mus. Bull. 107, p. 231, figs. 

Lower Devonic: Presque Isle Stream, Chapman, Maine. 

Ventricose, subquadrate to subov.ate shells, rather large for nuculoids. Equivalve, inequilateral. Proportion of height to iength variable, between 7:10 and 8:10. Greatest height 

just back of the beaks; greatest length near the midheight, sometimes above, smnetimes below. 

Umbones conspicuous, broad, protruding slightly above the hinge line; situated at the anterior two-sevenths to two-fifths; usually slightly prosogyrate to nearly vertical, occasionally 

strongly prosogyrate, especially when situated far forwar.d. Anterior end equal to about 

three .. fourths the total height, not quite as high as the posterior end, convexly rounded throughout, nearly horizontal for a short space in front of the beaks, subvertical for the greater part 

of the distance, and rounded into the ventral margin which is depressed convex to nearly straight. 

The portion of the shell iri front of the umbones does not exceed one-fourth the total length. 

The ventral extremity is below the midlength, just back of the beaks. Fro1n this point the 

ventraln1~rgin. is nearly or quite horizontal, ascending very little to the postventral extremity. 

Sometimes a very faint insinuation· or straightening of the ventral margin occurs posterior to · 

the n1iddle. From the postventral extremity, the posterior margin in the lower half rises to 

the rear as far as the upper margin of the posterior sulcus. This portion of the n~argin is n1ore 

or less concave near the middle, the concavity depending on the degree of development of the 

sulcus and being rather faint at ·best. The posterior extremity is a little above the sulcus at 

the middle of the posterior margin but below the midheight of the shell. Frmn it the posterior 

margin ascends vertically, or very slightly forward, in a depressed-convex, nearly straight line 

to the hinge extremity. Occasionally there is a small constriction in the 1niddle of "this portion, 

but it is much smaller than the ventro-posterior insinuation. The hinge extrmnity is obtusely 

· subangular or rounded. The length of the hinge line posterior to the beaks, which is equal to 

one-half to two-thirds the total length of the shell, generally nearer the fonner, is less than 

the height of the shell, varying from one-half· to two-thirds the height, generally nearer the 

latter; rarely it nearly equals t4e height. The hing~ line is straight or very depressed convex, 

usually slightly descending, frequently horizontal. 

With regard to the convexity of the shell, the broad, gibbous, overarching umbmies are 

very conspicuous. Below the umbones the body is inflated to different degrees in different 

shells, being nearly globular in some young individuals and always ventricose. The postumbonal ridge is rounded and extends at ~n angle of 30° or 40° from the vertical. The posterior 

sulcus is shallow and sometimes hardly discernible. It does not extend to the beaks. It is· 

bounded above by a lmy, narrow ridge which, when definable at all, is broader, lower, and less 

conspicuous than the postumbonal ridge. Between this secondary low indistinct ridge and 

the hinge line there is frequently a very faint, narrow furrow or depression of the surface. 

The degree of development of the posterior sulci and ridges is exceedingly variable. The 

depth of an average single valve is equal to half or nearly half the height. The point of maximum depth is situated at the dorsal third of the height, and either on or in front of the postumbonal ridge, at the midlength or slightly in front. 

Ligamenta! structure unknown. Apparently no cartilage pit.\ Dentition taxod<p1tic. A 

few sparse teeth are developed in front of the umbones. Behind the umbones the number of 

teeth could not be distinctly counted, but there appear to be between 12 and 16, nearer the 

latter number. The teeth' diminish in size toward the beaks. Muscular scars and pallial 

impression absent; not observed on any one of more than 50 specimens. Shell of moderate 

thickness; intimate structure not observed. · 

The surface ornamentation comprises tenuistriate lines of growth, occasionally crowded 

into low, obsolescent concentric ridges. No regular lamellose ornamentation developed. 

Very rarely on the body of the shell below the umbones exceedingly faint radial scratches or 

lines are discernible. · ' 
MOLLUSCA. 167 

Mn,ture shells have a length of 20 to 25 millimeters and a corresponding height of 14 to 

18 or 20 millimeters; two large individuals were 28_ millimeters long and 20 to 21 millimeters 

high. 

The distinguishing characters of the fossils are the ventricosity; subquadrate outline; high 

but short anterior end; full, overarching umbones; hinge line horizontal or slightly declining; 

hinge extrmnity n1ore or less definable; posterior margin vertical to retrorse in the upper half; 

vcntro-posterior mnarginatioi1; :faint and variable posterior sulcus, bounded by two obsolescent 

rounded ridges; occasional develop1nent of a second very faint sulcus; absence of muscular 

impressions in finely preserved specimens. 

Locality: Chapn1an sandstone, abundant 2 miles west of Presque Isle Stream and common 

at Presque isle Stremn, where the greater softness and finer grain of the sediments have permitted the speci1nens to becorne distorted in several directions. Some globular young individuals frmn locality 1099 J (Pl. XXV, fig. 8), representing one. of the n1any variations of the 

species at this locality, ·are indistinguishable fr01n "Otenodonta" crassa Beushausen, from the 

German Coblenz quartzite. No specimen observed had the lamellose ornamentation of the 

typicnl forms of Goldfuss's and Sandberger's species. 

U.S. National ~1usemn, cD,talogue Nos. 59773, 59774, 59775. 

OomzJarisons.-The variety kayseri Beushausen is distinguished from the typical form of 

T. gibbosa by the absence of lamellose n1arkings, the surface lines of growth being tenuistriate~ 

Beushausen retains Sandberger's species T. unioniformis as distinct from Goldfuss's T. gibbosa. 

T. unioniformis is supposed to be slightly lower and more transverse; to have the hinge line 

slightly n1ore arcuate and reclining, and to have a deeper and narrower sulcus and less regular 

sculpture; both forms, ~oweveJr, are lamellose. A glance at Bei1shausen's figu_re will show that 

the supposed distinctions of the two forms intern1ingle and interchange. Furthermore, the 

gren.t variability in the Chaprrtan shells, as well as in the Rhenish shells, in the proportion of 

height to length, the direction of the hinge line, and the strength of. the posterior sulcus affords 

convincing evidence that in spite of the lack of German fossils for study, the forn1s described as 

T. unionij01mis and ·r. gibbosa. ·represent a single species with lamellose concentric ornamentation. T'he Chapn1an v~rietal forn1 is tenuistriate and seems indistinguishable from the Brazilian "Palreone~Zo "orbignyi Clarke,· of the Coblenzian fauna of Rio Maecuru. One of the 

small globular speci1nens fro1n Maine is·indistinguishable from "Otenodonta" crassa Beushausen, 

and as the same fonn is also represented by Clarke 1 from Brazil, there can be little doubt 

that Beushausen's fossil is one of the forms of this variable and apparently long-ranging and 

widely distributed species of the lower half of the Eo-Devonian. The other synonyms given 

above are suggested by the oecurrence of similar or approximately similar forms in the Maine 

collections, which close study shows to be evidently specimens of the variety originally defined 

by Beushausen. 

The Chapman and Brazilian fossils, especially the former, closely approach Tellinopsis 

subemarginata Flall,2 from the New York Hamilton, but they lack the anterior faint sulcus 

and ridge usually developed in Tellinopsis. In Hall's fossil also the beaks are more persistently 

central or directed vertically or backward, and it is a thinner shell. Paleoneilo virginica I-Iall 3 

is a near ally, but is truJlsversely n1ore elongate and has the sculpture strengthened, becoming 

finely lamellose toward the postun1bonal ridge and sulcus. Paleoneilo perplana· Hall 4 is also 

similar to the Chapn1an fossils, but has less overarching umbones, and, like P. virginica, is 

transv-ersely 1nore elongate and has stronger ornamentation posteriorly·. The Chapman fossils 

also resemble the figures of Paleoneilo sulcata I-Iartt and Rathbun/ but that species is much 

flatter, with beaks narrower, not inflated or overarching, situated farther forward, and more 

decidedly prosogyrate; the sulcus is more persistently and strongly developed; a few minor 

points of distinction might be added. 

1 Clarko, J. M., Mus. nac. Rio do Janeiro Arch., vol. 10, pl. 8, fig. 14, 1899. 

2 :Hall, James, Paleontology of New York, vol. 5, pt. 1, p. 464, pl. 76, figs. 21-31, 1885. 

Dldom, p. 340, pl. 93, fig. 14. From bods of Hamilton ago, Patterson Creek, Va. 

• ldom, p. 339, pl. L, figs. 15-22, pl. 93, flg. 12. 'J:he species is from the New York Hamilton. 

G Hartt, C. F., and Uathbtm, H.., New York Lyceum Nat. Hist. A1mals, vol. 11, p. 124, 1875. See also Clarke, J. M., op. cit., p. 75, pl. 8, fig. 

13. 'l'ho spocios is from the Hamilton fauna, (Middle Devonian) of Erere, Para, Brazil. The.comparisons made above are based on the three type 

spoclmo.us of Hartt and Rathbtm preserved in the Cornell University collections. -
168 FAUNA OF THE CHAPMAN SANDSTONE OF MAINE. 

Genus DITICHIA F. Sand~erger, 1891. 

The genus Ditichia was founded by ·F. Sandberger 1 on some Lower Coblenzian taxodontic 

shells which have two strongly developed muscular septa dividing the cavity of the valve into 

a narrow central compartment with a lateral chamber on each side. The typ~s are from the 

Conde Valley, near Winnegen, in the Coblenz district. Sand berger erroneously identified his 

shells w!th a species from the Haupt quartzite of the Harz Mountains which had been described 

as Leda mira Beushausen,2 which is a different shell. In the typical Coblenzian forn1s thick 

s(}ptal ridges extend on the umbonal side of the two muscular scars; these ridges reach nearly 

to the ventral margin, producing a characteristic tripartite appearance in casts and giving 

them, as suggested by Sandberger, the appearance of a large Beyrichia. 

These typical forms, with their highly developed septa, 3 present an appearance so' remarkable 

among lamellibranchs that they would seem to make up a valid genus. Beushausen,4 however, 

has attempted to demonstrate that Sandberger's typical forms of _Ditichia are n1erely the 

young of Oucullella ( Oleidophorus) elliptica (Maurer), and that the posterior septum disappears 

with age and the anterior septum becomes sharp. 

In the Chapman shells the septa do not attain the bizarre and extreme development shown 

in typical Ditichia, but the material shows that the variability in the septa is due not to advancing age in the individual but to difference in degree of development in different individuals. 

The septa are faint or absent in some young shells and highly developed in some of the largest 

specimens, and vice versa. It is interesting to .note that simil,ar septal structures, a fairly 

strong anterior septum and weaker posterior septum, occur in the Leda-like Nuculana (Ditichia) 

securis Clarke,5 in the oval, nonsinuated Oleidophorus elliptica (Maurer), and in the emarginate 

Paleoneilo mainensis .and similar forms. There is also a faint approach to a posterior septum in 

addition to the umbonal septum in some forms of Adranaria securiformis (Goldfuss). 6 The . 

occurrence of these septate structures in such dissimilar forms tends to bear out Benshausen's 

suggestion that the character does not seem in itself to be of generic value. I doubt, however, 

whether Beushausen's explanation of the development of the septa as a .juvenile character is 

correct. On the contrary, inferences drawn from analogous structures in other lamellibranchs 

and in brachiopods lead to the conclusion that the development of these septa is originally a 

senile character. If the name Ditichia is used as indicating a separate genus, it will have to 

be restricted to the typical forms, having both the anterior and posterior septa well developed 

and extending nearly to the ventral margin. 

Genus PALEONEILO Hall, 1869. 

PALEONEILO (DITICHIA) MAINENSIS _Clarke. 

Plate XIX, figures 10, 12, 19; Plate XXV, figures 6, 9, 11, 13. 

1907. Palceoneilo mainensis. ·Clarke, New York State Mus. Bull. 107, p. 230, figs. 

Lower Devonic: Presque Isle Stream, and i.n the burnt district 2 miles westward; Chapman Township, Maine. 

cf. 1907. Palceoneilo ( Nuc1.'tlites) jolles. Clarke, idem, p. 232, 2 figs. 

Lower Devonic limestones: Dalhousie, New Brunswick. 

Large, moderately convex shells of regularly ovate outline, ~apering behind, the regularity 

of the outline slightly interrupted by a faint postventral constriction of the margin. Proportion of height to length varying from 74:100 in high.shells to 65 or 67:100 in the c01nmoner 

forms and to 60 or 61·:100 in the transversely more elongated specimens. Greatest length at 

or slightly below the midheight; greatest height indefinitely at or slightly in advance of the midlength. Umbones are moderately; broad, rarely central, usually situated between tl;w middle and 

1 Sandberger, F., Bemerkungen iiber Ditichia, eine neue Nuculaceen-Gattung aus dem Unterdevon: Neues Jahrb., 1891, vol. 2, pp. 104-105. 

2 Beushausen, Louis, Beitrage zur Kenntniss der Oberharzer Spiriferensandsteins: Abh. geol. Specialkarte Preussen, vol. 6, pt. 1, p. 90, 

pl. 3, fig. 15, 1884. 

a See Beushausen, Louis, Die Lamellibranchiaten des rheinischen Devon: K. preuss. geol. Landesanstalt Abh., new ser., vol. 17, p. 104, pl. 5, 

~u~~~. . 4 Idem, p. 105; K. preuss. geol. Landesanstalt Jahrb., 1891, p. 95. 

6 Clarke, J. M., Some new Devonic.fossils: New York State Mus. Bull. 107, p. 233, figs., 1907. 

e See Beushausen, Louis, Abh. geol. Specialkarte Preussen, vol. 6, pt. 1, pl. 6, fig. 1, 1884. 
MOLLUSCA. 169 

anterior third. They are slightly overarching; usually directed vertically, or nearly so, but 

often decidedly prosogyrate, especially when the beaks are farther forward. The anterior end 

includes one-third or 1nore of the total length and five-sixths or more of the height of the shell. 

The anterior 1nargi1~ is convexly rounded in a symmetrical paraboloid· arch. No lunule in frC!nt 

of the beaks. The forward extremity is just below the inidheight of the shell. The ,.anterior 

nlm·gin 1nerges into the ventral n:Largin in a broad curv:e. The ventral n1argin is usually bellied 

down; the ventral extremity is at the n1idlength, either directly under or, more frequently, very 

slightly behind the beaks. The ventral n1argin is symmetrically arched, except that the posterior third is constricted or faintly insinuated. The posterior margin is ill defined, owing to 

the convergence of the dorsal and ventral n1argins, and is symn1etrically rounded, with the 

posterior extrmnity usually at the inferior one-third or two-fifths the height of the shell, rarely 

near the Jnidheigl~t. There is no definable hinge extremity; the dorsal edge declines .rapidly 

fr01n behind the beaks and merges into the narrow posterior end. The hinge line behind the 

beaks is very depressed convex, nearly straight. The valves are moderately ventricose. The 

u1nbones are prominent and incurved over .the beaks. The bodJ7 is full below the beaks and 

slopes so as to produce a deep anterior end and a less convex posterior end. The posterior half 

of the surface includes a broad, undefined, very shallow sinus or flattening, sometimes so little 

developed as to be almost or quite unrecognizable. Behind this the surface is again rather" 

convex over the short distance to the postdorsal margins. The point of greatest depth of the 

shell ia situated below the umbones, slightly in front when the umbones are prosogyrate, variably between the dorsal one-third and one-fourth the height. In full, uncompressed shells the 

depth of the single valve is two-fifths the height or frequently a little less. Ligamental structure 

unknown. 

Clarke's lower figure shows, as is usual, no cartilage pit. The Maine specimens show no 

trace of an external ligament. However, they have one peculiar feature which is worthy of 

notice. Clean internal molds sometimes show a linear incision below the teeth extending back 

of the beaks nearly or quite to the posterior muscular scar. This may represent the sharp inner 

edge of the hinge plate or it m.ay perhaps indicate an elongated naiTow cartilage or internal 

ligament below the posterior hinge, such as exists in the recent taxodontic genus Glomus and 

its allies. 1 • 

Dentition taxodontic; five, six, or seven nuculoid teeth in front of the beaks and 20 or 1nore 

teeth behiild the beaks; of the latter those immediately behind or under the beak are 1ninu te 

and 1n1n1erous. The teeth increase in size posteriorly and are V shaped, with the apices directed, 

as is usual, toward the umbones. The n1uscular scars, especially the anterior one, are made 

conspicuous by a blunt septal thickening or deposition of shell on the umbonal side of each scar. 

The anterior septal ridge is the stronger and more persistently developed, occurs immediately· 

in front of the beaks, and extends directly downward or, more often, a little forward from the 

vertical. It is arched and tapers downward, extending less than halfway down, usually decidedly less than halfway. Except for this ridge or septum the muscular scars are only faintly 

impressed or defined. The posterior ridge is blunter and fainter than the anterior ridge, occurs 

less than halfway from the beaks to the posterior end of the shell, and is directed downward and 

backward. Frequently it is not definable. Pallial line faintly impressed anteriorly; not at aU 

impressed in clean n1olds posteriorly. Hence it is impossible to state whether or not the shell 

was sinupallinte. Shell thin, Hxcept for the thickening on the umbonnl side of the musculnr 

scar. 

In surface ornamentation the shells vnry from a few that are nearly smooth to those thnt 

. exhibit tenuous strire of growth. The largest specimen had n length of 32 millimeters and n 

height of 21 1nillin1eters. Ordinary mnture specimens have a length of 24 to 29 millimeters and 

a proportionate height. The smallest specimen observed was 7 millimeters high and 11 millinleters long. 

1 See Verrill, A. E., and Bush, K. J., Revision of the genera of Lediclre and Nuculidre of the Atlantic coast of the United States: Am. Jour. 

Sci., 4th scr., vol. 3, pp. 53, 60, figs. 1, 2, 1897. 
170 FAUNA OF THE CHAPMAN SANDSTONE OF MAINE. 

The distinguishing features of the species are. the rounded ovoid outline tapering behind; 

height generally two-thirds the length; umbones prominent, variably between subcentral and 

subvertical to the anterior third and prosogyrate; anterior end large and well developed; vertic.al margin arched and symmetrical except for a rather broad, very faint. insinuation or constriction postv~ntrically; posteriorly converging ventral and dorsal nlargins; moderate ventricosity; very faintly developed posterior sinus, which is occasionally hardly discernible; strong 

septal ridges on the umbonal side of the scars, stronger and more persistent on the anterior scar, 

smnetimes o bsol~scent on the posterior scar; septa thick, blunt, and extending less than half 

the height.; and tenuistriate surface. 

Locality: Chapman sandstone, Presque Isle Stream and 2 miles west of Presque Isle Stream 

(localities 1099 A and 1099 J) and Edmunds Hill (locality 1099 C'), Chapman Township, Aroostook Cqunty, Maine. -

Two forms of the species occur, both at Presque Isle Stream (1099 A) and' in the region west 

of Presque Isle Stream (1099 J). One form has the umbones subcentral and vertical, the sinus 

extremely faint," and the muscular septa less well developed. In the other form the umbones 

are more decidedly prosogyrate and situated farther forward, and the septa are more strongly 

developed. These characters, however, interchange, so that it has been considered advisable 

to unite the two forms in one species. Pa.leoneilo (Nuculites) folles Clarke frmn New Brunswick 

is a probable synonym, conforming with those Chapman specimens which .have the umbones 

forward and prosogyrate. 

U.S. N·ational Museum, catalogue Nos. 59776, 59777, 59778. 

Oomparisons.-Among the ovate, smooth, emarginate shells with well-develop.ed septa which 

approach Paleoneilo (Ditichia) mainensis may be n1entioned Paleoneilo crassa (Beushausen's 

Otenodonta crassa) ,t which is, however, less tapering posteriorly and higher anteriorly and in 

which the teeth in front of the hinge are more numerous. Paleoneilo prisca (Goldfuss) as figured 

by Beushausen 2 is also similar but is a narrower species with the beaks situated farther forward. 

Paleoneilo intermedia (Beushausen's Oucu.llella intermedia) 3 and Paleoneilo speciosa Beushausen/ 

especially the latter, are also closely similar but vertically narrower species. 

PALEONEILO MAINENSIS Clarke var. UMBONATA var. nov. 

Plate XXV, figures 16, 20. 

The collections from Presque Isle Stream (locality 1099 A) contain, with Paleoneilo 

(Ditichia) mainensis, two specimens which exhibit the normal variability in outline of 

P. mainensis but which differ from all the normal forms of the species in having the umbones 

much more highly developed, situated in advance of the anterior third, and directed decidedly 

prosogyrate. Some of the variability of the two specimens, however, may be due to distortion 

by pressure. In the ventricosity of the shells, arching umbones, large anterior end, subsymmetrically arched ventral margin, tapering posterior, faint post-ventral sinus, and ornamentation 

var. umbonata agrees with the usual forms of the species. The anterior septal ridge is moderately 

developed, short, and blunt, as usual; the posterior septal ridge in the two specimens at hand 

is not discernible. The high umbones, situated farther forward and strongly prosogyrate, 

will readily distinguish the present variety. · 

Locality: Chapman sandstone, Presque Isle Stream, Chapman Township, Aroostook 

County, Maine. 

U.S. National Museun1, catalogue No. 59779. 

Oomparisons.-Some of the forms of Paleoneilo mainensis approach the well-known 

American Paleoneilo constricta Conrad 5 but differ in having the anterior muscular septum 

persistently developed and in being more inflated; the Maine shells also lack the change in 

ornamentation posteriorly which characterizes the typical forms of P. constricta. 

1 Beushausen, Louis, Die Lamellibranchiaten des rheinischen Devon: K. preuss. geol. ·Landesanstalt Abh., new ser., vol. 17, p. 77 par:;, pl. 6, 

fig. 4 (not fig. 5, which i~ the young of the Tellinites (Koenenia) kayseri type), 1895; Coblenz or Ems quartzite of Rhens, Prussia. 

2 Beushausen, Louis, Beitriige zur Kenntniss der Oberharzer Spiriferensandsteins: Abh. geol. Specialkarte Preussen, vol. 6, pt. 1, p. 79, pl. 3, fig. 

16, 1884; as Ctenodonta prisca. 

a Beushausen, Louis, op. cit. (1895), pl. 5, fig. 16. 

• Idem, pl. 6, fig. 8. 

5 See Hall, James, Paleontology of New York, vol. 5, pt. 1, p. 333, pl. 48, figs. 1-16; pl. 51, fig. 17, 1885. 
MOLLUSCA. 171 

Genus LEDA Schumacher, 1817. 

Although the existence of taxodontic shells of characteristic lediform outline as low down 

in the Paleozoic section as the Ordovician has long been kriown, there has been some doubt 

as to whether these shells really exhibit the pallial sinus and cartilage pit characteristic of 

Lecla Schun1acher, or, as son1e have chosen to call it, the genus Nuculana. 1 The OrdovicianDevonian genus Adranaria ineludes tau-x:odontic lediform shells lacking both ~artilage pit and 

pallial sinus but is easily distinguished by having a low blunt radial septum or ridge on the 

interior of the shell. Such ledifonn taxodonts can, because of their umbonal ridge or septum, 

easily be placed where they belong, near Nuculites and Ctenodonta;· but in other Paleozoic 

shells resen1bling Leda even in the presence of a cartilage pit there is no trace of a pallial sii1us. 

Goodchild 2 has cn.lled attention to' some Carboniferous species of so-called "Leda" which 

distinctly lack the pallial sinuf? of the real Leda (N ucu'lana), and his observation as to the 

absence of pallial sinus has been corroborated by Hind; 3 in these shells a cartilage pit occurs. 

I-Iall 4 showed a cartilage pit in the Mississippian Leda pandorijormis, in which also the pallial 

·line was not observed. Goodchild and I-Iind have demonstrated the cartilage pit in the English 

Carboniferous "Ledas," which lack the pallial sinus. However, the diversity of genera based 

on the soft ani1nal parts, as in Area where many different generic types };lave the same external 

for1n of shell, should lead to ·hesitation before asserting actual identity of these primitive fossil 

Ledas with the recent Leda. It is apparent, from the little now known of the forms living in 

Paleozoic ti1ne as interpreted through the fossils, that even then there was at least as much 

diversification an1ong these for:ms as exists among their descendants of the present day. · 

The occurrence of a callosity 0) on the interior of these Paleozoic "Ledas," is of interest. 

In the n1ore recent and typical Leda the body of the shell below ·the umbones is full and inflated; 

but I-Iind has called attention to the fact that many Carboniferous species of Leda display a 

persistent thickening of the sh~~ll on the interior, or a flattening or faint depression ·on internal 

n1olds below the u1nbones. This character, indeed, is present in most though appa.rently not 

all Paleozoic "Ledas" and mt:Ly have sonie function similar to that of the umbonal ridge or 

septum of the ledif.orn1 Adranaria. This subumbonal depression .in internal molds is well 

defined in the Chapman Leda (?) harrisi. 

The Chapman specimens, unfortunately, do not indicate whether or not the pallial sinus 

and cartilage pit were present. Hence, the reference of .the fossils to Leda and the Ledidre 

mn,Y: be open to some question, in spite of the pronounced and typic~llediforn1 expression. 

LEDA HARRISI sp. nov. 

Plate XXV, figures 15, 19. 

Lediform shells of small to mediu1n size, length It times the height. Umbones vertical, 

or slightly directed backward (opisthogyrate), situated at the anterior two-fifths of the length 

depressed to the hinge line. .Anterior margin symmetrically arched, paraboloid, a trifle deeper 

than a semicircle. Forward extremity at the midheight. Ventral margin rounded, ascending 

only slightly toward the rear, n.onemarginate; ventral extremity directly below the umbo. 

Posterior end fairly broad for Leda, elliptically rounded, horizontal. Posterior hinge extremity 

not definable. Hinge margin back of the beaks nearly horizontal in the middle, ascending 

strongly toward and im.mediately behind the beaks; nowhere quite horizontal or descending · 

from the posterior extrmuity forward. Convexity depressed. A broad depressio!l or flattening 

on internal n1olds descends from the umbones at an angle of less than. 15° backward fron1 the 

vertical. This is most conspicuous near the midheight. The anterior end is convexly rounded, 

of rather subdued convexity. Posterior to the infraumbonal flattening, the surface again 

becomes convex in a rounded posterior ridge, which is discernible for one-half the distance 

I Nuculana Link, 1807, has priority over Leda Schumacher, 1817. According to Dall, however, the Nuculana of Link is a synonym of Nucula 

Lamarck. 

2 Goodchild, J. G., Notes on Carboniferous lamellibranchs (Ctenodonta and Nucula): Roy. Phys. Soc. Edinburgh Proc., vol. 11, p. 244, 1892. 

u Hind, Whoolton, A monograph of tho British Carboniferous Lamollibranchiata; pt. 2, Mytilidm, Arcidm, Nuculm: London Palmontogr. Soc. 

Pub., vol. 51, p. 176, 189i. 

• Paleontology of Now York, vol. 5, pt. 1, p. 332, pl. 4i, fig. 50, 1885. 
172 FAUNA OF THE CHAPMAN SANDSTONE OF MAINE. 

from the beaks. This ridge bears the point of greatest depth of the shell, at the midlength, 

a little below the dorsal margin and on a line to the beaks at an angle of approximately 40° 

from the vertical. There is no persistent umbonal ridge nor carina. The depth of the single' 

valve is equal to one~fourth the height or less. 

Ligamenta! structure and dentition unknown. Muscular scars 9f approximately equal size, 

the posterior scar possibly slightly the larger. Anterior scar distant from the beaks, situated 

at the forward extren1ity of the shell; fairly well impressed. Posterior scar situated about 

midway between the beaks and posterior extremity. No accessory scars observed on our two 

, specimens. Pallial line ~1ot in1pressed. Shell apparently thin. 

Surface apparently sn1ooth or with faint tenuistriate lines of growth. Internal molds quite 

smooth. The type is 7.6 millimeters long and 5 millimeters high; the depth approximately 

on.e-fourth the height for the single valve. A larger specimen is much flatter; it is 14.9'n1illimeters long and _9 millimeters high. 

The distinguishing features of the species are the broad posterior end; the length. of the shell, 

1! times the height; beaks at the anterior two-fifths; ventral extremity directly below the 

umbones; the infraumbonal flattening or depression of the internal mold; and the moderate 

convexity. 

Locality: Chapman sandstone, 2 miles west of Presque Isle Stream (locality 1099 J), 

Chapman Township, Aroostook County, Maine. 

U.S. National Museum, catalogue No. 59781. 

Oomparisons.-The species is somewhat similar to the Hercynian Leda described and 

figured by Beushausen 1 as Nucula kracht<£ Roemer but differs in having the ventral extremity 

directly below the umbones and the umbones farther back; moreover, L.- krachtre is a gibbous 

shell and appears to lack the infraumbonal depression of Leda harrisi. 

LEDA MINUTA sp. nov. · 

Plate XXVI, figure 1. 

Shell minute, ovate triangular; length one-half greater than the height. Anterior portion 

a broadly rounded parabola, deeper than a semicircle; posterior portion· abruptly narrowed, 

rounded at the extremity. Postdorsal margin concave, nearly horizontal in the hinder portion, 

but nowhere quite horizontal nor ascending from the beak to the posterior margin. Beaks 

broadly rounded, arching over the cardinal line; vertical or opisthogyrate. Dimensions, 

3 by. 2 millimeters. 

The internal mold is smooth, being devoid of ornamentation and muscular in1pressions. 

Locality: Chapman santlstone, Presque Isle Stream (locality 1099 A), Chapman Township, 

Aroostook County, Maine. 

U.S. National Museu1n, catalogue No. 59782. 

Oomparisons.-Leda minuta is readily distinguished from Leda harrisi, the other Leda of 

the Chapman sandstone, by its more minute size and more gibbous outline; it is sharper posteriorly and more bellied clown ventrally. Finally, Leda minuta lacks the more conspicuous 

median depression of Lecla harrisi. 

Leda minute£ resen1bles Leda brevirostris Hall, 2 from the Hamilton forn1ation of New York, 

but it attains only half the size, and its front margin is, n1ore deeply rounded. 

Family NUCULID.tE Adams. 

Several Nucula-like shells of the Chapman fauna possess characters which place them in 

an ·intermediate position between Dall's family ?Ctenodonta and Adams's family embracing 

the lat·er and recent Nuculicloo. To these forms I apply the name Nuculoiclea, classing them 

as a subgeneric group of the genus Nucula Lamarck to give thmn a legitin1ate taxonomic rank. 

Evolutionally these Paleozoic N uculas may more properly be considered as the ancestral stock 

out of which Nucula and perhaps all the true Nuculidoo have arisen. 

1 Beushausen, Louis, Beitrage zur Kenntniss des Oberharzer Spirifensandsteins und seiner Fauna: A bh. geol. Specialkarte Preussen, vol. 6, 

pt. 1, pl. 4, figs. 7, 12; 1884. 

2 Hall, James, Paleontology of New York, vol. 5, pt. 1, Lamellibranchiata, pl. 47, fig. 40, 1885. 
MOLLUSCA. 173 

Genus NUCULA Lamarck. 

Subgenus ~CULOIDEA subgen. nov. 

The distinguishing n1arks of N uculoidea are a distinct cartilage pit, as in Otenodonta albertina Ulrich, of the Upper Ordovician, and a nonpectinated ventral1nargin, which differentiates 

thmn from the true N uculas of the Cenozoic. The species 1Vucula oznma Hall= N. randalli 

:Hall and authors, of the Ha1nilton, is taken as the type of the group. 

Oucullea opima I-Iall wns described and illustrated in 1843.1 In 1870 2 Hall described 

Nucula randalli (without figun)s) and declared Oucullea opima I-Iall, 1843, to be identical with 

Nucula lirata Conrad, 1842. In 1885 3 Hall stated that after reexa1nining the original of Oucullea 

01Jima he unhesitatingly regarded JVucula opima Hall, 1843, as identical with J.lucula randalli 

I-Iall, 1870. J.V. opima has priority n,nd according to the rules of n01nenclature n1ust be retained. 

With regard to the supposed identity of N. lirata· Conrad and J.V. opima Hall, it is a fact 

that the great 1najority of specin1ens as ordinarily preserved are not distinguishable specifically, 

the finer ornamentation being only rarely discernible and the con~exity and outline being 

varit~ble both origin~lly and as a result of crushing. 

Two internal 1nolds (No. 201 A) in the Jewett collection at Cornell University, labeled 

'" Nuc'l.tla opima I-Iall, fro1n the I-Ia1nilton at Delphi, N. Y.," show distinctly a 'veil-developed 

cartilage pit under the umbones. A similu,r specimen with cartilage pit, fr01n beds of Han1ilton 

age at Cmnberland, :Mel., Is illustrated by Hall/ and the very closely si1nilar Nucula lirata 

Conrad, fr01n the I-Iamilton, is also known to have a cartilage pit.5 The l\iississippian Nucula 

ho'l.tghtoni Stevens, 6 fro1n the l\Jississippian of Ohio and beds of coiTesponcling age in Michigan, 

is known to have a cartilage pit. l\1ore recently nuculoid shells possessing a cartilage pit have 

been found in the Eo-Devo.nian of Gern1any, in several Taunuaian and ·coblenzian species. 7 

They occur also still lower in the geologic colunm, in the Ordovician, for E. 0. Ulrich 8 has shown 

thnt although in the Trenton species of his "group of 'Otenodonta' levata (Hall)" (=the "group 

of 'Otenodonta' socialis Ulrich," or subgroup under Myoplusia, described on p. 162) there is no 

cartilage pit, a n1ore or less undefined pit is developed in some Upper Ordovician forms, and· 

finu1ly "Otenodonta" albertina Ulrich 9 has a good cartilage pit and is congeneric with Nucula 

01Jima I-Iall. · 

The Paleozoic nuculoid shells ·Inentioned above agree with N ucula in general outline, 

configuration, pearly shell, and taxodontic hinge, as well as in having a cartilage pit. Apparently these shells confor1n, so far as these characters indicate, with typical Nucula. liowever, 

one of the characters conunonly associated with Nucula is the denticulate ventral margin on 

the interior of the shell. This denticulate or pectinate margin is developed in all the Recent 

and Tertiary species of N ucula exa1nined by me and l\h. Breger, comprising several dozen 

species, as well as in several Cretaceous forn1s. On the other hand, the Paleozoic shells otherwise identifiable with Nucula Rack the denticulations on the interior along the ventral margin. 

We hn.ve not discovered a single specin1en fron1 the Ordovician, Silurian, Devonian, or l\1ississippian which possesses the denticulate ventral 1nargin, except the little Nu.cula shumardiana 

I-Iall, from the l\1ississippian Spergen lin1estone of Indiana. Doubtful appearances of a crenulate nutrgin in this tiny species have been observed on son1e specin1ens fro1n Spergen Hill. 

This species appears, however, even externn.lly, to be n1ore nearly related to the recent Nuc?.tla 

pernula than to the other Paleozoic Nuculas. The persistent absence of the denticulate ventral n1argin in the early and :frequently large Nuculas and its persistent develop1nent in the 

Recent Nuculas furnish a ready and easy disti1iction. The nondenticulate and earlier forn1 1s 

1 Hall, James, Geology of New York, Rept. Fourth Dist., p. 197, fig. 78, No.3, 1843. 

2 Prollmino.ry Notice of the Lamellibmnchiata, No. 2, p. 3, 1870. 

a Paleontology of Now York, vol. 5, pt. 1, IJ. 315, 1885. 

• Idem, pl. 45, fig. 27. 

G Idem, flg. 25. 

o Idem, fig. 3land p. 324. 

1 :Boushausen, Louis, Die Lamellibranchiaten des rheinischen Devon: K. preuss. geol. Landesanstalt Abh., new ser., vol. 17, pl. 4, figs. 9 

(N.fornicata), 17 (N. grandawa), 19 (N. aquisgra.nensis), 20 (N. krachtre), etc., 1895. 

s Ulrich, E. 0., 'l'he Lower Silurian LameUibranchiata of Minnesota: Geology of Minnesota, vol. 3, pt. 2, P~eontology, p. 581, 1894. 

e Idem, p. 598, pl. 42, figs. 76-82. 
174 FA UN A OF THE CHAPMAN SANDSTONE OF MAINE. 

here designated Nuculoidea, from its resemblance to Nucula. Some of the Triassic and 

Jurassic Nucnlffi may possibly belon·g in the same group. 

In the type species of N uculoidea the accessory muscular scars are well developed. In 

add~tion to the pedal retractory muscles, situated one above the anterior occlusor scar and one 

over the posterior scar, there are usually discernible in the antero-umbonal region three minute 

muscular impressions, the strongest one hindmost; in well-preserved specimens a fourth minute 

and .strong muscular scar is situated at the tip of the umbo. Hall figured, apparently, still a 

fifth minute scar between the anterior pedal retractor and foremost un1bonal scars. These 

five represent the full quota of "umbonal scars," but usually only three are visible. From 

the position of these scars in Nuculoidea randalli, N. lirata, and other species of Nuculoidea, 

I had origin~lly regarded the larger end of the shell bearing these scars as the posterior end, 

in which case the beaks would have been (as is usual in Nucula) directed backward. Examination of the Cretaceous Nucula percrassa Conrad, however, led to the belief that in this shell 

the beaks were directed backward and that the large end was the anterior end, as in normal 

N ucula; therefore, the umbonal scars, being situated on this large rounded end, were necessarily anterior. This view as to the antero-umbonal position of the umbonal scars is supported 

and corroborated by the Devonian Paleoneilo constr:icta (Conrad), where the mnarginate end 

is practically known to be the posterior end and where the umbonal scars are situated in the 

·narrower, anterior end. It may be regarded as established, therefore, that the u1nbonal scars 

are always antero-umbonal; and this feature affords another means of distinguishing the 

anterior fron1 the posterior end in these Paleozoic shells. Such umbonal scars are present 

in several species of Nuculoidea and in many more species which appear to belong to Nuculoidea; they are absent in modern N uculas. This would seem, at first sight, to be another 

distinction between Nucula and Nuculoidea, were it not that similar scars are discernible in 

Nttwula percrassa Conrad, from the Cretaceous Ripley formation/ which has the denticulate 

margin of the real Nucula. Similar umbonal scars are also present in some forms of Paleoneilo, 

in Koenenia, and in the group· of Nuculites oblongus, and are exceedingly well developed and 

specialized in the Barrandean species erected by N eumayr into the genus Myoplusia. The 

occurrence of similar scars in these diverse taxodontic groups suggests the belief that they are 

not of generic -value. 

The species which will probably fall under Nuculoidea may be divided into three groups, 

as follows: 

Group of Nuculoidea opima (Hall}. Umbones twisted to a vertical position or actually 

faintly prosogyrate; the anterior end usually longer and semilunulate under the beaks. 

Group of Nuculoidea aquisgranensis (Beushausen). Umbones opisthogyrate; anterior end 

convexly rounded and usually larger; posterior outline semilunuliferous. ·This group includes 

shells having the common cordate, ovate, or veneriform Nucula expression. 

Group of Nuculoidea 0) niotica (Hall). Umbones opisthogyrate; posterior n1argin truncate, nearly· vertical; anterior margin also nearly straight, producing a characteristic vertically 

triangular outline. 

Representatives of all three groups appear in the Chapman sandstone. Nuculoidea bellatula 

sp. nov. belongs to the group of N. opima. N. trigonale is related to the triangular Nuculoideas 

of the "third group. The group of N. aquisgranf?nsis includes N. cordata sp. nov. and Nuculoidea 

cf. N. aquisgranensis. 

NucULOIDEA BELLATULA sp. nov. 

Plate XIX, figure 4. 

Small triangular shells, astartiform; height nearly equal to or slightly greater than the length. 

Umbones situated typically back of the midheight, ~nd variably directed forward or nearly 

vertical. The posterior(~) end (as determined from analogy with Nucula (Nuculoidea) fornicata 

Goldfuss, N. (N.) opima Hall, etc.) is high but rather short; the posterior margin descends from 

the umbones and forms the longest margin of the shell; the hindmost extremity is usually below 

1 Jewett collection, Cornell University, No. 7509 (original number 202). From Columbus, Miss .. 
MOLLUSCA. 175 

the 1nidheight. The ventral ma~rgin is deeper but short; together with the anteroventral and 

posteroventral portions it includes approximately a semicircle. .The ventral extremity is near 

the middle. The anterior (?) rnargin is faintly concave in front of the beaks. Convexity 

n1oderate. Surface smoothly rounded; umbones depressed to the hinge line. Greatest convexity below the umbones and n.bove the midheight. ·Depth of the single valve equal to onefourth .the height or less. Liga1nent, dentition, and muscular scars unknown. The sculpture 

casts show fine regular concentric lines. of growth, which are fairly conspicuous over the ·middle 

of the body and die out anteriorly and posteriorly. In the type there are 9 or 10 lines in the 

space of 3 millimeters at about 5 millimeters below the beak. There also appear in the typical 

forn1s two or three distant varicose strire of growth. The type has a height of 10 millimeters 

and a width of 9.5 millimeters. Another specimen is 10.5 millimeters high and 10 millimeters 

broad. · 

The distinguishing features of this fossil are the height equal to the length, or greater; short 

and high posterior end, convexly rounded; umbones prosogyrate to subvertical'; anterior margin 

concave; ventral margin semicircular; moderate . convexity; fine bellis tria te lines of growth 

with a couple of varicose stri~ of rest. 

Locality: Chapman sandstone, west side of Edmunds Hill (locality 1099 M), Chapman 

Township,· Aroostook County, :Maine. 

U. S. National Museum, catalogue No. 59783. 

O'omparisons.-Nuculoidea bellatula is closely similar to Nucula [Nuculoidea] lodanensis 

Beushausen/ fron1 the Upper Cohlenzian of Rhenish Prussia, but the latter is a trifle wider and 

has a shallower ventral margin and its ornamentation is not bellistriate. In ornamentation 

N. bellatula is similar to Nucula. [Nuculoidea] fornicata Goldfuss, N. [Nuculoidea] sandbergeri 

Beushausen, N. [Nuculoidea] pelmensis Beushausen as figured by Beushausen,t ·and N. [Nuculoide(t] bellistriata Conrad, 2 but these species have a different outline. N. fornicata Goldfuss, 

however, approache~ it closely but is less elongated vertically. Tellinomya [? Nuculoidea] 

socialis Foerste 3 (not Gt~nodonta socialis ffirich), from what has been called the Clinton formation in Ohio, is approximately similar to Nuculoidea bellatula in outline and conve~ity, but is 

not quite so high vertically. 

NuoULOIDEA coRDATA sp. nov. 

Plate XIX, figure 6. 

Shell small, obliquely cordate; height nearly equal to the length; greatest length, 8.3 millimeters, is across about the inferior fourth; height from. beak to middle of ventral extremity 

equnl to about seven-eighths the length, or 7.3 millimeters. Beaks only slightly if at all 

behind the middle, directed posteriorly, arching- slightly beyond the hinge line. The anterior 

margin is gently convex throughout, nonlunulate, and extends forward and downward at an 

angle between 30° and 45° to the anteroventral extren1ity, where it rOtmds into the ventral 

n1argin .. The ventral margin is broad and shallow, and its lowest point is at the midlength. 

The posterior outline·of the shell is convex below the umbones and also convex distally, but 

concave in the middle, thus producing a heart-shaped outline with the anteroventral end of the 

shell con~idered as apex. This heart-shaped outline is a little unsymmetrical, the postventral 

'lobe being slightly more protuberant than the postdorsal. The shell is of moderate convexity. 

1'he mnbones are not particularly conspicuous. The surface is evenly rounded, except for a 

faint appearance of a narrow truncated strip below the beaks posteriorly, and a steepened slope 

n.long the anterior margin. The point of greatest depth is at the midlength, a trifle above the 

midheight and slightly·in advance of the beaks. The depth of the single valve does not attain 

a fourth the height. fiinge features and muscular scars unlmown. 

The sculpture casts show regular, even, "bellastriate" li'nes of growth, much finer than 

in L. bellatula and upon close examination just visible to the naked eye. About 10 or 11 of 

1 Doushrmson, .l~ouis, Dio Lamollibmnchiaton dos rheinischen Devon: K. preuss. gcol. Landesan~talt Abh.,ncw sf,)r., vol.17, p. 48, pl. 4, figs. 

o, 7, 1895. 

2 Paleontology or Now York, vol. 5, pt. 1, pl. 46, figs. 1-9, 1885: "Cornifcrous" limestone of the Ohio a.pd Indiana region. 8 J?ocrsto, A. F., Fossils of the Clinton group in Ohio and Indiana: Geology of Ohio, vol. 7, pt. 2, p. 563, pl. 37, fig. 12, 1895. · 
176 FAUNA OF THE CHAPMAN SANDSTONE OF MAINE. 

these fine rait;ed ,lines n1ay be counted in a width of 2 ·n1illimeters, 5 millimeters from the beak. 

Two or three distant obscure. varices, or impressed strire of' rest, are also discernible. 

The distinguishing features of this fossil are the gently rounded anterior 0) n1argin; the 

concave posterior (~)margin; broad, shallow ventral margin; high form with height nearly equal 

to the length; moderate convexity; and very fine bellistriate surface markings. 

Locality: Chapman sandstone, loose on Edmunds Hill (locality 1099 .C'), Chapm,an Township, Aroostook County, Maine. 

U.S. National Museum, catalogue No.· 59784. 

Oomparisons.-This species is similar in size and high trigonal outline .to Nuculoidea trigonale, 

also found on Edmunds Hill, but is easily distinguished by having a convex anterior margin 

and concave posterior n1argin instead of both margins straight. Nuculoidea cordata resembles 

Ledopsis perobliqua Beushausen 1 in the high trigonal outline and general outline of the n1argins, 

but in the German species the posterior or concave outline is vertical and the beaks are farther 

posterior. Nucula (J.Vuculoidea) varicosa Hall, 2 another member of the group of Nuculoidea 

aquisgranensis, has the high outline of_ N. corclata, but differs in the greater size and stronger 

convexity; moreover, like Ledopsis perobliqua Beushausen, it has ·the beaks farther back. The 

remaining and typical forn1s of the group of J.Vuculoidea aquisgranensis are lower, more transverse shells. 

NucuLOIDEA cf. ~· AQUISGRANENSrs (Beushausen). 

Plate XIX, figure 7. 

cf. 1895. Nucula n. sp. aff. N. aquisgranensis. Beushausen, Die Lamellibranchiaten des rheinischen Devon, p. 5~, 

pl. 4, fig. 16. I 

Lower(?) Coblenzian: Laubach Valley, Prussia. 

cf. 1895. NuC'ula aquisgranensis. Beushausen, idem, p. 56, pl. 4, fig. 25. 

Stringocephalus limestone (Meso-Devonian): Breiniger Mountain, near Aachen, Germany. 

A species very close to Nuculoidea aquisgranens,is (Beushausen) is represented in the Chapman fauna by a single specimen, of which, unfortunately, the umbonal and dorsal region is 

broken away. The speci1nen represents a small left ( ?) valve, 10 millimeters long and probably 

about 7.5 1nillhneters high, of venerifonn outline, like Beushausen's N. aquisgranensis and Hall's 

N. dijjidens, especially the former. The n1uscular scars are preserved; that at the larger 

(anterior) end is slightly the larger. The pallial line is si1nple. The lines of growth are strongly 

marked but not quite bell.istriate. The specin1en is moderately convex. 

Locality: Chapn1an sandstone, west side of Edmunds Hill (locality 1099 M), Chapman 

Township, Aroostook County, Maine. 

U.S. National Museum, catalogue No. 59785. 

NucuLOIDEA TRIGONALE sp. 1~ov. 

Plate XIX, figure 8. 

Outline subvertical, triangular, with the height a little less than the' length. The greatest 

length, 8.3 n1illime'ters, is across the postventral and anteroventral extre111ities near the base 

of the shell; the ·height, from beak to 1niddle of ventral 1nargin, is 7 1nillimeters. The beaks 

are depressed to the hinge line, inconspicuous, narrow, and directed posteriorly ( ~). The 

anterior 1nargin is straight fron1 the beaks to the antero-ventral extren1ity, and is directed at 

an angle of 45° with the vertical; it is equal in length to the height of the shell. The posterior 

margin is also straight to the post ventral extremity; it is nearly as long as the anterior 1nargin · 

and makes with the latter an angle of 80°. The ventral 1nargin is sym1netrically arched, with 

the lowest point at the midle11gth. Surface evenly rounded, except that along the upper 

posterior margin the surface is truncate. The shell is of moderate co'nvexity, the depth of the 

single valve equal to less than one-fourth the height. The point of greatest depth is slightly 

t Beushausen, Louis, Beitrii.ge zur Kenntniss des Oberharzer Spiriferensandsteins: Abh. geol. Specialkarte Preussen, vol. 6, pt. 1, p. 93, pl. 6, 

fig. 18, i884. . 

2 Hall, Jame:c>, Paleontology of New· York, vol. 5, pt. 1, p. 319, pl. 46, figs. 12-23; pl. 93, fig. 4, .1885; Hamilton group of New York. 
MOLLUSCA. 177 

above and behind the middle. lbe umbones are depressed to the hinge line. Hinge features 

unknown. Muscular scars not irnpressed. The sculpture casts show very :fine "subbellistriate" 

lines of growth, hardly visible to the naked eye and much fainter than in N. bellatula. As in 

that species, these fine lines are interrupted by a couple of distinct, coarse strim or varices of rest. 

The type is 8.3 1nillimeters long and 7 millimeters high. Another imperfect specimen is of about 

the smne size. 

Locality: Chapman sandstone, west side of Edmunds Hill (locality 1099 M), Chapn1an 

Township, Aroostook County, ~1~tine. 

U. S. National Museu1n, cat:tlogue No. 59786. 

Oomparisons.-This species agrees in outline, ornamentation, and depressed convexity with 

Nuculoiclea ( n putilla (Clarke)/ f:r01n the Sihuian of the Rio Trombetas, Br~tzil; but the Brazilian 

and ~1aine shells have the greatest depth on respectively opposite sides of the beak. The '' sn1all 

central, subtriangular tooth and s.ocket" in the hinge on the Brazilian internal1nolds, as described 

and figured by Clarke, may possibly represent the .cartilage pit of Nucula and Nuculoidea. 

An undescribed species of Nuculoidea of similar triangular outline, from the Hamilton forn1ation at East Berne, Albany County, N. Y., is more globular or inflated and has slight. differences 

in the details of outlu~e. Nuc·uloidea trigonale also recalls in general appearance Paleoneilo 

O'revic'lLla Clarke, 2 from the higher Portage formation (Neo-Devonian) of western New York; 

but Clarke's species has the postventral mnargination characteristic of Paleoneilo. Ledopsis 

trigona Beushausen 3 has the characteristic Nuculoidea outline. It is distinguished from N. trigonale by being 1nore gibbous and having the beaks n1ore nearly cen:tral. 

Superfamily PTERIACEA Dall. 

Family PTERINEIDJE Dall. 

Genw3 PTERINEA Goldfuss and allied genera. 

The difficulties in nomenclature encountered in attempting to classify the fossils of t]J.e 

Chapman fauna falling under the general definition of Pterinea were so complex that it was 

found necessary to revise the original conception of the genus and to redistribute the original 

species included by Goldfuss under the name, erecting new genera for the distribution of wellknown species which differ fron1 the true Pterinea. 4 In this revision the first species mentioned 

by Goldfuss, Pterinea lmvis, was retained as the type of the genus Pterinea Goldfuss s. str., and 

the following diagnosis of charncters was formulated: 

1. Hinge line long. 

2. Vah:es equal in circumference but unequal in convexity; the left valve always convex, the right valve in 

earlier stages of growth convex, but less so than the left, becoming flat or concave (resupinate) at maturity. 

3. Ears well developed, more or Jess distinctly differentiated from the body of the shell, reaching to or in front 

of the anterior edge of the body of the shell. ~ 

4. Wings more or less distinctly differentiated from the body, flattened, reaching posteriorly as far as the extreme 

posterior margin of the shell. 

5. Body of the shell with its, longer axis produced ventrally at a considerable angle from the hinge line. 

6. Posterior muscular scar distinct, large, and more or less sharply impressed in the shell wall. 

7. Anterior muscular scars small and generally strongly impressed, situated on the ear, not body, of the shell. 

8. Ligamenta! area well defined and longitudinally striate. 

9. Posterior later~l teeth (or tooth),distinct, elongate, and situated at or near the junction of wing with the body 

of the shell. 

10. Anterior cardinal teeth distinct, short, separated from the lateral teeth, and inclined at large angle from 

· hinge line. 

ll. Surface smooth, with concentric growth lines and radial lines or ribs. 

1 Clarke, J. M:., Tho Silurio.n fauna of tho H.io Trombetas: Mus. nac. Rio de Jo.neiro Arch., vol. 10, pl. 2, figs. 10, 11, 1899 (author's English ed., 

p. 16, 1900); described as Anodontopsis or Slnzka putilla. 

2 Clarke, J. M., Tho Naples fauna in western New York: New York State M:us. M:em. 6, pt. 2, p. 425, pl. 15, fig. 16, 1904. 

8 Boushausen, Louis, Beitriigo zur Kenntniss der Oberharzer Spiriferenso.ndsteins und seiner Fauna: Abh. geol. Specialkarte Preussen, vol. 6, 

pt. 1, p. 93, pl. 4, fig. 11, 1884. 

4 Williams, H. S., On tho revision of the :mollt1sk genus Pterinea Goldfuss: U.S. Nat. Mus. Proc., vol. 34, pp. 83, 90, 1908. 

50245°-No. 89-16--12 
'· 

178 FAUNA OF THE CHAPMAN SANDSTONE OF MAINE. 

The type species of the genus, Pterinea lcevis Goldfuss, was found in the Coblenzian at Ems, 

Germany. The Ordovician species, Pterinea d~missa Conrad and Avicula ampliata Phillips, 

seem to belong to .the genus Pterinea 'as emended. These shells. resemble Leiopteria Hall,t 

but that genus has the right valve convex throughout life, though less so than the left, and 

has the ligament thin and nonstriated, or with only a single groove (canaliculate). Pterinea 

as restricted also resembles more or less closely Leptodesma Hall and Pteronites McCoy, but 

these genera are edentulous, or have a single posterior lateral tooth close under the ligament and 

not oblique to the hinge. Pteronitella ~illings is also smooth, like Pterinea s. str.; but, like 

Leiopteria, it is biconvex and with different dentition. 

The genus Micropteria Frech 2 was proposed for a subdivision of Goldfuss's genus, which 

differs from Pterinea lcevis and Pterinea s. str. in having the left valve more deeply inflated 

and in having a less definable: anterior ear. Pterinea ventricosa Goldfuss is the genotype of· 

Micropteria Frech. In ornamentation, dentition, convexity, etc., Micropteria conforms with 

Pterinea. . 

The radially ornamented shells which have hitherto been confounded with Goldfuss's 

genus Pterinea have· been distributed for the most part among To1maia W1lliams, Follmannella 

Williams, Actinopterella Williams, and Cornellites Williams.3 ' 

The genus Tolmaia Williams was proposed and defined to include finely radiate forms like 

Pterinea lineata Goldfuss; it corresponds. to Frech's "gruppe der Ptennea lineata." Ir{ erecting 

the genus, Frech's original definition was closely followed. 

In the "gruppe de:r: Pterinea ventricosa" Frec}:_l included a form 'to which he gave the name 

P. ostreiformis. A more distinctly ornamented related shell is represented by the species 

Pterinea mainensis Clarke/ from the Moose River sandstone of northern Maine, and this 

species was taken a~ the. type of a genus for which the name Follmannella was proposed, in 

appreciation of the valuable contribution made by Dr. Otto Follmann in elucidating the characters of the Pterineas. Follmannella. was based. on the backward sweep or recurving of the 

body of' the shell in old individuals, a character well developed in some of the more recent 

Ostreidre. . ' . . 

After such radially lined forms as P. lineata Goldfuss were prov.ided for by the erection 

of the genus Tolmaia, it was found that the faunas of Maine contain an important set of similar 

species, both valves of which are uniformly convex, the right valve lacking the resupination 

characteristic of Tolmaia and the typical Pterinea groups. The genotype described under the 

name Pterinea radialis Clarke is from the Chapman sandstone .. 

In this dissection of the· heterogeneous Pterinea of Goldfuss and authors still another 

distinct group was recognized, to which Frech called attention in discussing his '' gruppe der 

Pterinea costata." In erecting the genus Cornellites for this group, Pterinea fasciculata Goldfuss was chosen as the type, with the hardly distinguishable Pterinea flabella Conrad as an 

American cotype. The most conspicuous feature of Cornellites is the coarse, usually unequal 

ribbing on the left valve. . 

The g'enus Pterinea and the family Pterineidre Dall, to which it belongs, ~re believed to 

be restricted in range to the Paleozoic. All the species of Pterinea are dimyarian (heteromyarian); the anterior adductor scar is smaller than the posterior, but both are distinct in adult 

shells. The closely allied genus Avicula Bruguiere ( = Pteria Scopoli) is monomyarian in adult 

shells, though the young shells exhibit an anterior adductor scar, which disappears with age. 

In young forms both Avicula Br.uguiere and Pterinea Goldfuss s. str. are biconvex, "though the 

left valve appears to be generally the more strongly convex .. With age the right valve of Pterinea becomes resupinate. This resupinate character of the .right valve is observed in Pterinea, 

Micropteria, Tolmaia, Follmannella, a:nd Cornellites, but the gerius Actinopterella is biconvex 

throughout life. 

1 Hall, James, Paleontology of New York, vol. 5, pt. 1, p. xiii, 1885. 

2 Frech, Fritz, Die devonischen A viculiden Deutschlands: A bh. geol. Specialkarte Preussen, Yo!. 9, pt. 3, p. 80, 1891. 

a Williams, H. S., op. ·cit., pp. 86-89. · · 

4 Clarke, J. M., Some new Devonic fossils: New York State Mus. Bull. 107, p. 201, 1907. 
MOLLUSCA. 179 

Genus FOLLMANNELLA Williams~ 1908. 

In Follmannella are included the following hitherto described species: 

Follmannella mainensis (Clarke), genotype. 

Actinopteria (Pterinea) fronsacia. Clarke, Some new Devonic fossils: New York State Mus. Bull. 107, pp. 198, 201, 

1907. Gaspe Basin, Quebec; Delos J .. ake dam and Moosehead Lake, 7 miles north of Kin eo, Maine. 

Pterinea ostre·ijormis. Frech, op. cit., p. '98, pl. 11, figs. 9-9c. Spirijer cultrijugatus zone, in the Eifel, on the mountain opposite Lissingen, not far from Gerolstein, Germany. · 

Avicula sp. Kayser, Die 17'auna des Hauptquarzits und der Zorger Schiefer des Unterharzes: K. preuss. geol. LandesnnstaJt Abh., new ser., vol. J, p. 18, pl. 8, figs. 1, la, 1889. Lower Eo-Devonian of the Harz Mountain~ (the 

Cloistet· grounds near Michaelstein). Included in Follmannella because Frech identified the shell with Pterinea 

ostreijormis, though it seems to be rather a shell of the type of Limopteria (Paropsis) chevanus. 

Act·inopteria lmmboldti. Clarke, The PaJeozoic faunas of Para, Brazil, pt. 2, Devonian Mollusca: Mus. nac. Rio de 

.Janeiro Arch., vol. 10, pl. 5, figs. 3, '7, 11, 12, 1899 (Author's English ed., p. 47, 1900). Lower Coblenzian fauna 

of Rio Maecuru. 

Avicula obz.t:quata. Hall, Paleontology of New York, vol. 3, p. 285, pl. 51, figs. 9, 10, 1859. Pentamerus limestone of 

. tho ]~ower Helderberg group: Schoharie County, N.Y. 

Pterinea correcta. ~arrande, Systi3me silurien du centre do la Bohi3me, vol. 6, particularly pl. 356, figs. 14-22, 1881. 

Pterinea obsequens. Barrande, idem, particularly pl. 357, fig. 26. [The other figures, of smaller shells, show hardly 

any recurvation and indicate that the recurvature in this species is an adult or senile character. The preceding" 

species, P. correcta Barrande, is in the young state apparently similar toP. obsequens, as may be determined from 

the lines of growth in mature shells.· Pterinea cuneata Barrande (op. cit., pl. 356) is a shell of the same type and 

js apparently not at all recurved. The shells passing UJ?.der these three name~ occur together and are apparently 

modifications of the same specific type, showing that in these Silurian early members of Follmannella the recurvaturo is perfectly attained only af maturity. The species are from etage E2.] . 

Avil-'Ula danbyi. :McCoy, Systematic del3cription of the British Paleozoic rocks and fossils in the Geological Museum 

• of tho University of Cambridge, in Sedgwick, Adam, and McCoy, Frederick, British Paleozoic rocks and fossils, 

p. 258, pl.l, figs.ll-15, 1852. [The species is abundant in the greenish Upper Ludlow quartzites of Benspn Knot, 

Kendal, Westm6roland. It is like the Bohemian Silurian species, recurved only slightly and only· in older shells. 

'l'ho three Silurian species here referred to Follmannella are not very characteristic forms, being variable with 

regard to the recurvature, which b•2comes more fixed in the Devonian forms. The Silurian shells also have tho 

ribs rather stronger than in the typical forms of the group. Follmannella danbyi occurs in the late Silurian of 

the Cobscook Bay region at Whiting;, Palls Point, Dennysville, Long Cove, Horan Head, etc., Washington County, 

Maine.] · 

Leiopteria rafinesq'l.tii (not Hall). Walco~t, Paleontology of the Eureka district [Nevada]: U.S. Geol. Survey Mon. 8, 

p. 166, pl. 5, fig. 10, 1884. Lower Devonian limestone: Brush Peak and Atrypa Peak, Eureka district, Nev. 

These shells are all of moderate or depressed convexity, with more decidedly explanate 

,, mnbone than Corn·2llites. The right valve is resupinate and, on the whole, concave or flat. 

The anterior auricular portion is f11irly wei~ developed but hardly separable from the body by 

any definable byssal sinus in typical forms. The shells are large, and the two typical species, 

Pollmannella mainensis ·and Pollmannella ostreiformis, Frech, are among the largest Paleozoic 

lmncllibranchs known. Each one of the species is usually decidedly larger than any of the· 

other pterinoids in the fauna in. which it occurs. 

1'he shell structure in the· typical species, Pollmannella mainensis, is also characteristic; 

the main n1ass of the shell is strongly lamellar or concentrically foliaceous, with the radial 

strjre confined to an outermos·fi thin layer. Frech's figure of. P. (P.) ostreijormis indica.tes a 

s:in1ilar shell structure. 

FOLLMANNELLA 1\L\INENSIS (Clarke). 

Plate XVI, figures 1-6; Plate XVII, figures 1-11. 

?1907. A1;iculopecten alcis. Clarke, New York State Mus. Bull. 107, p. 195, fig. 

Lower Devonic: 'Mooseheacl Lake, 7 miles north of Kineo, Maine. 

1907. Aviculopecten flmnm.iger (pars?). Clarke, idem, p. 196, left-hand figure only. 

Lower Devonic. Askwith Sieling, ;Misery Stream, and Moose River, Maine. 

1907. Pterinea 1nainens1:s (pars?). Cla.rke, idem, p. 201, figs. (?except lower right-hand figure). 

Lo,\rer Devonic. 'l'elos Lake dam and Moosehead Lake, 7 miles north of Kineo, Maine. 

1907. Pt-erinea radialis (pars). Clarke·, idem, p. 207; lower figures only. 

]~ower Devonic. Matagamon Lake and elsewhere in Somerset County, Maine. 

This species is abundant in and characteristic of the Moose River sandstone of Somerset 

County, Maine, and probably occurs ·also at Gaspe, Quebec. Shells of this type do not occur 
180 FAUNA OF THE CHAPMAN SANDSTONE OF MAINE. 

in the Chapman sandstone· fauna. The mature shells are easily recognized by their large 

size, depressed convexo~concavity, recurvature, nu1nerous radial lines, and foliaceous shell 

structure. 

Outline obliquely rhomboid, with the lower half prolonged backward in n1ature shells. 

Height nearly·but not·quite equal to the length; the proportion of height to length varies between 8:9 and 21:22. Greatest height at about the posterior extremity of the hinge. Hinge line 

long and straight, continuous op. both sides of the beak, generally not more than four-sevenths 

the length of the shell, rarely exceeding five-sevenths the length except that in younger individuals which have not attained the recurvature the hinge line may be equal to the length of 

the shell. The posterior wing, though distinctly developed, is comparativ~ly small and sometimes not sharply demarcated from. the body; it includes ~n angle of about 25°. The posterior. margin of the wing is deeply concave; the lower half curves upward and forward; the 

upper haJf recurves to the rear and meets the hinge at an angle of 45° to 65°. The anterior 

auricular portion is large but because of the almost total lack of any definable byssal sjnus is 

not conspicuously demarcated from the body of the shell. The byssal sinus is extremely faint, 

being represented by an obscure constriction of the upper anterior margin slightly below the 

·hinge line. The body of the shell is large and includes at the umbones an angle of over 70°, 

occasionally as high as 90°. The beaks do not protrude appreciably above the hinge line and 

are directed upward and slightly forward; they are commonly situated between the anterior 

o:r~e-third and three-eighths the length of the hinge, generally nearer the latter, occasionally 

at about the midlength of the hinge line. The oblique height or axis of the body is about 

equal to the length of the shell, sometimes slightly less, but is decidedly greater than the oblique 

or transverse width of the body. 

In 1nature shells the forward extremity of the shell is on the auricular expansion, only 

slightly in advance of the anterior margin farther down. The anterior margin is gently curved 

in the upper half, at an angle of 80° to 85° with the hinge line, ·and swings in a broad catenaric 

quarter circle into the ventral margin. The ventral n1argin is strongly convex, with the lowest 

point directly below or sl~ghtly in advance of the posterior hinge extremity; thence arching 

strongly upward, then forward. The posterior margin of· the body is paraboloid, much more 

deeply convex than the ventral margin; the upper posterior margin of the body extends far 

forward at a very acute angle (less than 45°) to the hinge line. In mature shells the posterior 

portion of the body is well behind the posterior hinge extremity. In the young shells the 

contours are quite different and exceedingly variable in outline; there is some variability of 0 

course in the old shells, but the backward recurvature is a common chttracter at full maturity. 

The depressed-convex form is characteristic. The umbonal region on the body is moderately 

convex, but the convexity of the main surface of the body is very slight. The slope forward 

over the auricular portion is generally slightly concave, but there is no· sharply definable byssal 

sinus on the surface. The ear is depressed convex. The wing is concave and nearly but not 

quite "flat," in the plane of the margin. The right valve is depressed convex on the umbo, 

which is lower than that of the left valve, but concave over the greater portion of the surface; 

as a whole, the right valve is slightly concave fitting up into the cavity of the left valve. The 

body cavity of the shell, between right and left valves, is apparently very slight, being less 

than one-sixth the height of tlie valves. 

Ligamenta! area broad and striated. 

Cardinal teeth, about four in each valve; the foren1ost is slightly th~ stronger. The second 

and third cardinals in the right valve are generally united above in a narrow inverted V, or tend 

so to unite. The cardinal teeth are narrow ridges directed radially, parallel to the oblique axis 

of the· shell. There is a single strong posterior lateral tooth in the left valve situated at the 

junction of the wing with the body. In the right valve there is a still stronger radial -ridge or 

posterior lateral tooth underlying that· of the left valve, and a fainter ridge above it. The 

anterior muscular scar is situated on the ear at the junction with the body. , It is very deep 

and well marked and is underneath and in front of the foren1ost cardinal tooth. Two very 

small umbonal scars are also present at the apex of each valve; the posterior scar is a little the 
MOLLUSCA. ',::}81 

higher. The posterior adductor 1nuscular scar is very faint and indistinct in all the specimens 

ex~unined. It appears, however, to have been large. It is situated at the extremity of the 

posterior laterals, n1ostly on the body of the shell. The shell structure is characteristic in these 

fossils, which are readily recognized by the foliaceous laminre <;>f which the bulk of the shell substance is composed. These lmninm are black, indicating a high organic content; they are concentric and without indications of the radial ornan1entation, which is confined to an outermost, 

thin, n1embranaceous layer. l-Ienee, unless this outer layer is present the shell appears to be 

only concentrically ornamented. Cmnpare A'vicula (Follmannella) obliquata Hall (op. cit.), 

tho internn.l n1old of which, likewise, appears to be only concentrically n1arked, whereas the 

exterior is raclin1ly ornan1ented~ No 1nicroscopic sections have been n1ade. 

The surface ornan1entation consists ~ssentially of more or less unequal radial lines on the 

body of the left vn1ve, crossed by concentric strire of growth; these strire are closer together and 

more pron1inent on the wing, whE~re the)7 furnish the dominant ornamentation. On the forward 

part of the body, near the anterior Inm·gin and on the ear, the radial lines are absent, this pot:.. 

tion of the shell being Inm·ked only by concentric lines. The radial lines vary considerably in 

size and arrangmnent. Plate :XVII, figure 3, shows a· specimen with close subequal radial 

lines; Plate XVI, figure 1, shows a shnilar closely lineate forn1, but here the i·adin1 lines are 

unequn.l, a finer line being intercalated between two norn1al lines. Usually an intermediate 

radial line is developed between each adjacent pair of primary lines and occasionally a still finer 

single line appears on one or both sides of tllis intermediate one. No one type of radial ornanlentation is dmninant; the same shell1nay have in one portion several lines subequal, whereas 

i~1 another portion an intermediate line n1ay be intercalated between each two primary lines, in 

still another portion there may be a~1 even finer lineation on one or the other side of the internlediate lines, and occasionally such a third fine lineation may be observed on both sides of the 

intern1ediate lines. In all the specin1ens observed the radial lineation begins to fade over the 

1niddle of the body, toward the front, and near the tipper anterior n1argin no radial lines are 

discernible. This portion of the surface is covered with .faint concentric strim, which are most 

conspicuous and. best developed on the ear. 

The wing is n1m·ked by coneentric coarse strim or fine wrinkles; a few very faint, thin radin1 

lines n1ay be observed on the wing in the best preserved specin1ens, but ordinarily the wing 

appears to be only concentrically n1arked. 1 IIi some specimens there is an impressed line and 

abrupt change of ornan1entation which causes the wing to be sharply demarcated from the body. 

In other shells this i1npressed line is absent and the wing is less abruptly demarcated from the 

body. The concentric lines on the wing also cross the body, where they are well developed but 

con1n1only subordinate to the rn.dii; occasionally, in areas on the body of the shell, the concentric lines may be as strong as the radial. Ornamentation of the right vn1ve unknown. 

The species is large for a pterinoid shell, the specimen figured in Plate XVI, figure 5, being 

65 1nillin1eters high and 80 n1ilJlin1eters long. This is an unus-ually broad vari.ety. Fr~gments 

of still larger specin1ens have been observed. 

The posterior recurvature is a constant character in mature specimens of the species and 

occurs occasionally in son1e srr.L~ller specin1ens. In general the recurvature in young shells is 

not so well defined, frequently there is not the slightest indication of it. 

1'he variability in width is :shown by the narrow shells illustrated in Plate XVI, figures 1 and 

3, and the wider shells illustrated in Plate XVII, figur~s 1 and 2. Plate XVI, figure 5, shows 

an unusually wide or elongated shell, which is also decidedly more strongly convex than any 

other speci1nen, and the anterior margin differs son1ewhat by being protuberant in the middle. 

Such specin1ens may perhaps, in large collections, prove to be a distinct variety or species. 

For the specific nan1e I haYe adopted mainensis Clarke, in spite of the fact that in Clarke's 

text descriptions of both Aviculopecten alcis and A. flammiger Clarke precede that of Pterinea 

mainensis, for the reason that under the name Pterinea mainensis is given the :first full description and illustration of the typical and especially the adult or mature, normal form of the species. 

I Sinco tho abovo description was written I have seen an unusually clean external mold that shows the surface markings in perfection and 

Indicates tho occurrence of fine radial lines on the wing. 
182 FAUNA OF THE CHAPMAN SANDSTONE OF MAINE. 

The form called Aviculopecten alcis Clarke is not quite mat'ure and the figure represents the shell 

with no visible anterior wing. Under Aviculopecten jlammiger Clarke two species are described, 

and the description applies p·articularly to a "strongly radiated shell" unlike typical specimens 

of Follmannella mainensis.' Fina~ly, owing to the wide distribution of the species in the Moose 

River sandstone of Maine, the name mainensis is particularly appropriate, though of course,· 

under the laws of priority, this fact in itself would have no weight. 

Locality: Moose River sandstone, between Parlin Pond and Detroit, Somerset County, Maine. 

The species is abundant in the richly fossiliferous gritty calcareous sandstone filled with Leptocmlia jlabellites (Conrad), Chonetes rJ;ovascoticus Hall var. canadensis Billings, Leptostrophia 

perplana (Conrad), L. blainvillei (Billings), Ohonostrophia complanata Hall, and Spirij"er murchisoni (Castelnau). 

U. S. National Museum, catalogue No. 59787. 

Oomparisons.-Follma"!nella mainensis closely resembles· the German Eo-Devonian Follmannella ostreiformis (Frech) and from the figures might easily be .mistaken for it. Frech's 

species, however, is a very gibbous shell, whereas the Maine fossil is characteristically depressed 

convex,. The anterior margin is more protuberant in F. os~reiformis than in normal F. mainensis, 

but in this respect the Maine shells figured in Plate XVI, figure 5, and by Clarke 1 approach 

Frech's species. The German shells also exhibit more profuse cardinal dentition. 

From Actinopteria (Follmannella) humboldti Clarke the Maine fossil differs in having a much 

larger auricular expansion and the beaks not so anterior; the shell is larger and the ornamenta-. 

tion finer. 

From I-Iall's Avicula (Follmannella). obliquata Follmannella mainensis may be distip.guished 

by its finer and more abundant radii, a character that will also serve to distinguish the 

Maine shell from the other Silurian species, as well as from Follmannella fronsacia (Clarke); 

which occurs in the Gaspe fauna at Gaspe, Quebec, and in the Moose River sandstone of Somerset 

County, Maine. · 

Two of Clarke's figures, one of Pterinea radialis/ from Matagamon Lake, Maine, and one of 

Aviculopecten flammiger, 3 show forms that very closely resemble young shells of Follmannella 

fronsacia. 

Genus ACTINOPTERELLA Williams. 

Several species of a group of radiately lined pterinoid shells occur in profusion in the Chapman sandstone fauna. The generic characteristics of this group are the numerous radiate lines · 

on the surface and the convexity of both valves, the latter feature distinguishing it from Tolmaia 

and allied pterinoids; in which the right valve is resupinate or concave in adult shells. The 

presence of both cardinal and lateral teeth distinguishes the group from Actmopteria Hall. The 

lateral teeth, however, are close to the hinge line, and in this respect also the shells differ from 

the pterinoids, in which the posterior lateral teeth are on the border between wing and body. 

To this group the generic name Actin:opterella was applied. 4 It was founded upon the specific 

form named Pterinea radialis, by Clark~,S and figured in his first and second figures but not in the 

third and fourth, which represent Follmannella mainensis and probably Follmannella fronsacia 

(Clarke), respectively. 

The diagnosis of the' genus includes the following characters: 

l. Size small; length not over 35 millimeters. 

2. Shape of shell, ·oblique pterinoid, with posterior wing and anterior ear both developed. 

3. Both valves strongly convex; left valve ventricose with narrow oblique body; right valve convex from beak 

to ventral.margin, generally less convex than left valve, but not becoming resupinate with maturity; rar.ely nearly 

equivalve. · 

4. Umbones slightly protruding beyond hinge line .. 5. Ligamenta! area well developed, striated. 

6. Cardinal teeth present; three or four in number. 

1 Clarke, J. M., Some new Devonic fossils: New York State Mus. Bull. 107', p. 201, left-hand figure, 1907. 

2 Idem, p. 207, lower left-hand figure. 

a Idem, p. 196, right-hand figure . 

. 4 Williams, H. S., On the revision of the mollusk genus Pterinea Goldfuss: U.S. Nat. Mus. Proc., vol. 34, p. 87, 1908. 

u Clarke, J. M., op. cit., p. 207. 
· MOLLUSCA. 183 

7. Lateral teeth (or tooth) well developed and close to ligamenta! area, not on the margin of body and wing. 

8. Anterior muscular scar small and deep, situated on the ear. 

9. Posterior muscular scar obscure, large. 

10. Smface ornamentation, fine or strong radial ribs on body and wing and occasionally on ear of left valve; radial 

ribs on body of light valve generally obscure but occasionally strong·. 

The well-lm.own Devonian genus Limoptera Hall, of which L. macroptera (Conrad) is the 

genotype, presents son1e similarity to Actinopterella.. Hall's genus includes large, nearly erect 

pterinoids with numerous fine nonfasciculate ribs frequently obsolescent; the two valves are 

nortnnlly unequal, and the right valve is frequently convex, though often resupinate. Actin~ 

opterella is distinguished from Limoptera by having the right valve always convex and the 

left valve more gibbous and obhque: In Actinopterella the anterior ear is always conspicuously developed; it is the foremost part of the shell, and is separated from the body of the shell 

by a vertical sinus. In Limoptera the anterior ear is never well developed; when present at all it 

is not separated fron1 the body by a vertical sinus, and the forward extremity of the shell is the 

anterior. margin of the body rather than the ear. Finally, Limoptera is described by Hall as 

· having, in L. macroptera, only two cardinal teeth, and the single posterior tooth ·is defined as 

"oblique." The dentition of Li.Jnoptera is therefore quite different from that of Actinopterella, 

where the single posterior tooth is close to the hinge line and where there are three to five cardinal teeth. '"!"here should be no difficulty in distinguishing at sight the small, oblique, strongly 

eared, biconvex Actu1opterella from the large, nearly erect, earless or obscurely eared and 

semiresupinate Linioptera. 

Actinopterella also resemblE~s superficially the genus Actmopteria, 1 which was described by 

I-Iall in 1883 and 1885 to il1c~ude shells that differ fron1 Pterinea in being biconvex, in having fine, 

numerous radial riblets, ·and, particularly, il1 being edentulous· and without a well-developed 

strin,tcd ligamenta! area. Of the dozen or n1ore New York Devonian shells described. by Hall 

as Actinopteria, the only specie::; known definitely to exhibit this combination of generic characters is Actinopteria decussata Hall .. Although Actinopterella agrees with Actmopteria s. str., 

in biconvexity and approximately in ornamentation, size, and general appearance the genus 

Actmopteria I-Iall s. str. is edentulous and has a lin~ar nonstriated ligan1ent. Most specimens of 

·Paleozoic Actmopteria and of pt.erinoid shells in general appear to be edentulous, owing to poor 

preservation. Specimens. showing the teeth are very rare, and those with cardinal teeth are 

exceedingly uncommon. I-Iowever, a large number of specin1ens of Actinopteria decussata have 

been examined by geologists; the species is everywhere common under diversified conditions 

of preservation in the arenaceous Hamilton forn1ation of eastern New York, the shales of central 

N cw York, and the calcareous beds of western New York, and in none of these have teeth ever 

been recorded or, so far as known, observed. Large series in the Cornell University collections 

have also been exanlined duril1g the preparation of this paper. The absence of teeth and conspicuous ligament in A. decussata must therefore be ascribed, for the time being, at least, to 

originn,l absence rather than to poor preservation. 

The genus Actinopterella includes several species among the lamellibranchs of the Chapman fauna, and in addition. the following species pr.eviously described: 

Avicttl(t reticulata Goldfuss (not Risinger, Sowerby, nor Weller). Frech, Die devonischen Aviculiden Deutschlands: 

Abh. geol. Specialkarte Preussen, vol. 9, pt. 3, 1891. German and western European Meso-Devonian. 

Pterinea lind.~troemi. PhHippi., Ueber die echte "Avicula reticulata Risinger:" Deutsch. geol. Gesell. Zeitschr., vol. 

52, p. 561, fig. 2, 1900. [The real Avicula reticulata of Risinger is shown by Philippi 'to be an Aviculopecten. Philippi's species, from the Silurian of Gotland, seems to be an Actinopterella, though the right valve has not yet been 

described. On the other hand, the shell figured by Sowerby. 2 as A.vicula reticulata Risinger represents a different 

genus which has the curvature, ornamentation, oblique posterior lateral teeth, and strong ligament of Tolmaia, 

Cornellites, and Tiogana. This shell, which hafl been renamed Pterinea sowerbyi M:cCoy,3 should probably be 

included in Cornellites along with Pterinea hians McCoy and some. similar shells occmring in the Eastport quadrangle, Maine, as should also Act'inopteria reticulata Weller,4 although these Silurian species do not quite attain 

the pronounced coarse ribbing of the typical Devonian Cornellites species.] 

1 Hall, James, Paleontology of New York, vol. 5, pt. 1, p. 107, 1885. · 

2 Murchison, R. I., The Silurian system, pt. 2, p. 614, pl. 6, fig. 3, 1839. 

a Sedgwick, Adam, and McCoy, Frederick, British Paleozoic rocks and fossils p. 263, 1855. 

4 Weller, Stuart, Paleontology of New Jersey, Paleozoic faunas, p. 245, pl. 22, fl.!?· 3, 1903. 
184 FAUNA OF THE CHAPMAN SANDSTONE .OF MAINE. 

Pterinea tenuistriata. McCoy, op. cit., p. 263, pl. 1, I, fig. 4. [The types are from the Upper Ludlow of Benson Knot; 

Kendal, Westmorelarid, but the species is widely distributed in the I.udlow of Brecknockshire, Caermarthenshire, 

Shropshire, and Westmoreland.] • 

Pterinea rhombopsia. Barrande, Systeme silurien du centre de la Boheme, voL 6, pl. 217, box IV, fig~:~. 1:-3, 1881. 

Eo-Devonian of Konieprus ( etage 'F2). 

A1:icula·(Pterinea) conjortans. Barrande, idem, pl. 218, figs. ll, 12, 15, 16, 18. Eo-Devonian of Konieprus (etage F 2). 

Am:cula textilis. Hall, Paleontology of New York, vol. 3, p. 288, pl. 52, figs. 9, 10 (?); pl. 53, figs. 2, .3, 5, 7, 10, 1859. 

[This Helderbergian shell has the ligament broad and striated. According to ·weller 1 the right valve is convex 

No teeth have yet been obsl::lrved, b~1t the species is apparently a.n Actinopterella.] 

Actinopteria boydi (Conrad). Acad. Nat. Sci. Philadelphia Jour., vol. 8, p. 237, 1842. Hamilton, l\bdison County, 

N.Y. Upper Silurian shale. 

Actinopteria tenuistriata. Hall, Paleontology of New York, vol. 5, pt. 1, p. 120, pl. 84, figs. 5, 6, 1884. Ithaca shale 

member of the Portage formation. [Described by Hall as having the "right valve smaller, nearly equally convex," compared with the left valve. Such apparently convex right valves are not uncommon near Ithaca, but 

the specimens are incomplete and small; the right valves at maturity, when complete, are resupinate in front. 

If Hall's A. tenuistriata is a mature shell with the right valve really conv~x throughout it belongfl to the genus 

Actinopterella.] 

A few Meso-Devonian or Neo-Devonian species from Frech's groups of Avicula reticulata, 

Avicula wurmi, and Avicula marice may belong to ActinoptereUa, in addition to Avicula reticulata 

Goldfuss (not Risinger)~ 

The genus Actinopterella is first recognized in the Ordovician and ranges through the 

Silurian and Lower and Middle Devonian. 

No species of Actinopterella is at present known above the middle Neo-Devonian (the 

Ithaca shale member of the Portage formation), and there is doubt as to the certain occurrence 

of the genus as high as the Neo-Devonian. The greatest known development of Actinopterella 

is in the marine -beds of Upper Ludlow age in Great Britain, in the ·Baltic province, and in the 

Chapman sandstone, of late Helderbergian age, in Aroostook County, Maine.· In the early and 

typical Actinopterella the radial markings on the body of the right valve are nearly as strong as 

on the left valve. In such Meso-Devonian forms as A. boydi (Conrad) radial markings in the 

right valve are confined to the wing, the body being nearly or quite smooth. The· boydi type 

also occurs in the Si).urian. 

AcTINOPTERELLA RADIALIS (Clarke). 

Plate XV, figures 1-17; Plate XXIII, figures 6, 8, 9, ll-1:3. 

1907. Pterinea radialis (pars). Clark~, New York State Mus. Bull. 107, p. 207, upper figures only; lower right-hand. 

figures are Follmannella mainensis (Clarke). 

Lower Devonic: Presque Isle Stream, Chapman Township, Aroostook County, Maine (not "Matagamon Lake 

and elsewhere "). 

1907. Pteronitella peninsulre. Clarke, idem, p. 212, figs. (internal molds of the right valves of the species). 

Lower Devonic: Presque Isle Stream, Chapman Township, Aroostook County, Maine. 

Outline obliquely rhomboid, obliquity varying from 25° to 40° from the perpendicular, 

commonly 30° or a little more. Height less than the length, the ratio varying from 12:13 in 

only slightly oblique specimens to 2:3 in mucronately winged or very oblique specimens. Greatest height commonly just back of the middle; in a few very oblique specimens as far back as the 

posterior two-thirds. Hinge line long, continuously straight on both sides of the beak, and 

including the greatest length of the shell. Frequently the hinge line is prolonged posteriorly in 

a mucronate extension. The posterior end is acutely pointed; the anterior end is rounded. 

Clarke's figure of Pterinea radialis shows the anterior end too sharp. The posterior wing is 

large, distinctly developed, concave, and set off from the gibbous body and umbones by a sulcus. 

In the right valve the wing is somewhat less distinctly demarcable from the umbones and body. 

The posterior margin of the wing is concave; the lower part of the posterior margin of the wing is 

directed upward and somewhat forward; the upper part is usually directed backward at an angle 

of 40° to 70° witb.. the hinge, or very ntrely is nearly vertical. . The anterior ear is large, conspicuous, and well developed; rounded; height slightly greater than the length. The ear is 

1 Weller, Stuart, Paleontolo~y of New Jersey, Paleozoic faunas, p. 332, pl. 43, fig.l3, 1903. 
MOLLUSCA. 185 

separated fro1n the body by a broad sinus whlch extends vertically downward or slightly backwn,rd. The insinuation of the anterior margin reaches half or occasionally as much as threefifths the length of the anterior mid of the shell. The front of the ear is obtusely rounded; the 

extreme upper portion curves backward, rounding into the hinge line. The length of the ear 

ranges between one-third and one-half that of the body proper. The body of the shell includes 

at the umbones an angle of less than 60°. The beaks protrude above the hinge line; that of the 

left valve is usually higher than that of the right. They are situated between the anterior 

two-fifths and ~ne-third the length of the hinge line, and in a few mucronately extended specimens are only one-fourth the length from the front. The oblique height, or oblique axis, of the 

body is one and one-third to one and one-half timea the oblique width of the body, commonly 

nearer the latter proportion. The forward extremity of the shell is on the ear, below the hinge 

line. The anterior n1argin includes with the hinge line an angle of about 60° or a little less. 

The ventrn1 1nargin is deeply eon vex, nearly semicircular; the lowest point is three-fifths the 

length or n1ore frmn the front. The posterior margin of the body is convex, with the hindn1ost 

extren1ity at the lower third or fourth; the hinge extremity generally reaches in front of this, 

particularly in n1ore oblique speciJ?lens, and is frequently directed above it. In 1nucronnte 

specin1ens the hinge extremity extends a trifle beyond the posterior extremity of the body. 

Both vah-res ·are strongly convex throughout. The left valve is ventricose; the right valve 

usually is less convex than the left valve. The umbones are highly inflated and incurved. 

The point of 1naximun1 d~pth of the valves is on the oblique axis of the body, varying from the 

n1idhe.ight to the upper quarter, ,\rhence the slope is strongly convex over the body of the shell 

townrd the anterior sinus and just back of the beak. The depth of the left valve is equal to 

three-tenths the length of the oblique axis. The right valve is a little less convex but is variable, l'J 

being in son1e specin1ens nearly or quite as deep as the left valve. The anterior ear is strongly .-. 

cmn-rex. The posterior ,ving is flattened, concave, nearly in the plane of the margin, and is 

sharply clmnarcated from the body, especially umbonally. In the right valve the wing is a 

little less flattened than in the left and a trifle less distinctly demarcated from the body. The 

byssal sinus is shallow, broad, and undefined. It is vertical or occasionally slightly inclined 

backward, especinlly in the 111ore oblique specimens. The ligament is in a narrow, deep 

escutcheon, which is continuous in front of and behind the beaks. In front of the umbones the 

str.iateclligan1ent arches upward over the c;ardinal teeth. The area in the left valve is larger and 

wider than in the right valve and is nearly in the plane of the margin of the vah,es. In son1e 

specimens it is 1narked by three or four wrink'lecllongitudinal strire. In one or two right valves 

examined the area is similarly striated but is more elevated___:.that is, not' so nearly in the plane 

of the margin. The margins of the ligamenta! strip are parallel. The anterior n1uscular scar 

is small but rather deep. It is situated in front of the umbones, at the base of the foren1ost 

cardinal tooth, or between the ear proper and the byssal sinus. The posterior scar is several 

times larger than the anterior scar, but is shallower. . It is situated partly on the body, but 

mostly on the wing, and is rounded subcircul~r to quadrate in outline .. The pallial line is feebly 

impressed and sitnple, but partakes of the broad, shallo,v insinuation or constriction anteriorly 

in the region of the byssal sinus. Dentition variable in specimens taken fron1 the same rock 

layer. In the sin1plest types there are three or four simple cardinal teeth in t4e right valve and 

four or fi \

7 0 in the left. These teeth are narrow radial ridges, slightly inclined posteriorly. 

They may become thickened 01: ridged, or even divided, in various ways on different shells. 

The cardinal teeth are all situated in front of the umbone~. There is a single posterior lateral 

tooth in en,eh vah-re, situated as elosely as possible to the hinge line and parallel with it for the 

greater length of the tooth. That of ·the left valve is slightly the longer and stronger and is 

. situated below that of the right valve. 

,. 

Body of the shell of the left valve marked by low, rounded, flexuous radial riblets; which 

begiri back'·<?f the byssal sinus and are most dist~ct on the poste_rior half and on the lower 

half of the bo.f!.y. The riblets are equal or subequal in width and strength in most specimens; 

in others a finer elevated radial line is intercnJated between two adjacent normal riblets. There 

are from 16 to 3~ riblets on the body in different individuals, those in front being very 'faint 
186 FAUNA OF THE CHAPMAN SANDSTONE OF MAINE,· 

and obscure. The interspaces are narrower than the. riblets above, but become as wide· as 

the riblets, or slightly wider, below. The ribs increase by intercalation, a fine one forming 

between each normal pair and quickly developing to the strength of the rest. The body of 

the shell is crossed by obsolescent concentric lines of growth, including a few somewhat distant 

stronger varices. The wing is too poorly preserved in the specimens to warrant a definite 

statement that radial ornamentation is altogether absent on this portion of the shell, but if it· 

is present it is very much subdued. In the material at hand the wing appears to be smooth 

·or marked only by fine concentric lines of growth which may aggregate into low, undulose, 

obsolescent varices. The ear and byssal sinus are marked only by concentric lines of growth, 

which are higJ:Uy lamellose and conspicuous on the ear and forward part of the sinus. No 

distinct radial riblets or lines are discernible on sinus or ear. Of about a dozen right valves 

only one shows radial ornamentation anywhere, that one (the best in the collection) having 

one or two extremely faint, short, interrupted, narrow ridges, or exceedingly subdued riblets, 

on the posterior half of the body near the umbones. They are exceedingly obscure and may 

be adventitious. 1 If the specimens examined by us represent the real conditions, the right 

valve may be regarded as smooth and devoid. of radial ornamentation. A couple of the better 

specimens show only fine concentric lines and a few distant, somewhat stronger, imbricose 

varices over the body. These concentric. lines converge and become much stronger and more 

imbricose toward the ear and forward part of the sinus, as in the left valve. The wing appears 

quite smooth. 

The largest specimep. in our colle~tion is a shell of less than usual obliquity, 27.5 millimeters 

high and 30 millimeters long along the hinge. The usual size is between three-fourths and 

seven-eighths of that giyen. The dimensions of the smallest specimen are about two-thirds 

those of the largest. 

The distinguishing characters of this fossil are its siZe and outline; the large, well-developed, and conspicuous ear, behind which a broad, shallow sinw:; extends downward or slightly 

posteriorly, causing half to three-fifths of the anterior n1argin to be slightly insinuat.ed or constricted; anterior margin inclined about 55° to the hinge; oblique axis inclined 48° to 65°, generally about 60°, to the hinge line;' the strong ventricosity and protruding umbones, with right 

valve convex, but usuaily less. ventricose than the left; the ornamentation on the ear and sinus 

consisting only of strong concentric lamellm; the posterior wing nearly (apparently quite) 

smooth; radial ornamentation consisting of 16 to 32 broad, elevated lines or riblets confined 

to the body, and especially the posterior half; riblets flexuous, with interspaces narrower· or 

at most only slightly wider than the riblets; ribs generally equal or subequal, occasionally 

increasing by implantation and showing rarely strong and weak riblets alternating; right valves 

without radial ribbing. 

Locality: Chapman sandstone, Presque Isle Stream (locality 1099 L), Chapman Township, Aroostook County, Mai11e, where the·species is very abundant, there being oyer 50 specinlens in the material at hand. This form is very distinct from Actinopterella aroostoolci, described 

below, which is fron1 Edmunds Hill. 

U. S. National Museum, catalogue No. 5978$. 

Comparisons.-In the smooth wing and ear the species is like the Helderbei·g Avicula 

communis Hall, 2 which is recorded throughout the Helderburg, but it is most common in the 

shaly New Scotland ("Delthyris") limestone. Specimens from Albany County, N. Y., show 

a striated ligament. In Hall's species, however, the right valve is resupinate, so that it can 

not be even congeneric with Actinopterella radialis Clarke; the ribs are also more distant from 

each other, the ear is smaller, and there are other· dis'tinctive features. The British Upper 

Ludlow species Actinopterella mesoclathrata (McCoy) conforms with Actinopterella generically J_.~ 

and with A. radialis specifically in outline, convexity, and variability and in having the radial 

ornamentation confined to the body, but its ribs are much finer and more closely set. 

1 Compare the right-hand figure of Pterinea (Pteronitella) incurvata Clarke, op. cit., p. 210. 

2 Hall, James, Paleontology of New York, vol. 3, p. 286, pl. 52, figs. 1-7; pl. 53, Iigs. 1, 4, 6, 1859. 
MOLLUSCA. 

AcTINOPTERELLA AROOSTOOia (Clarke). 

Plate XV, figures 18-23; Plate XVII, figures 14-16. 

1907. Pterinopecten aroostooki. Clarke, New York State Mus. Bull. 107, p. 199.· 

Pterinea edmundi. Clarke, idem, p. 203, figs. · , 

Lower Devonic: Edmunds Hill, Chapman Plantation, Aroostook County, Maine. 

187 

This species closely resembles A. ra,dialis in outline and general aspect, but may be distinguished by several particulars. The ribs ·and their inters paces are somewhat different. in 

the two species. In A. aroostooki the posterior wing is distinctly radially ribbed, instead of 

being nearly or quite smooth; the ligament is nearly or quite in the plane of the margin and 

widens posteriorly instead of having the edges parallel; the shell is also strongly ribbed externally over the ligament; the radial ribbing extends farther forward, including the anterior 

byssal sinus; and the ear is also more or less distinctly ribbed radially. The right valve is 

distinctly ribbed on the body and over the ligament on the posterior wing. In A. aroostooki 

the ear is somewhat smaller, the beaks are situated farther forward, and the shell is usually 

less oblique and slightly less ventricose than in A. radialis Clarke. 

Outline obliquely rhomboid; obliquity varying generally between 24° and 35° from the 

perpendicular, commonly about 30°, very rarely 45°. Ratio of height to length varying from 

12:13 to 5:8; average about 3:4. Greatest height back of the middle, at about two-thirds the 

distance. from front to back. liinge line long, continuously straight on both sides the beak, 

and including the greatest length of the shell; frequently pennate posteriorly, but not, so far 

as known, n1ucronate. Anterior end of the hinge line generally rounded, rarely slightly angular; 

posterior end acutely pointed, rarely rounded.. The posterior wing in both valves is large and 

concn.ve, nearly in the plane of the margins, and distinctly demarcable from the umbones and 

body. The posterior margin of the wing is deeply concave; the lower part of this margin is 

directed upward and generally a little forward;. the upper part of the margin, which includes 

most of the p~sterior margin of the wing proper, is directed backward at an angle of 40° to 

60° with the hinge line; rarely as much as 80°. The posterior hinge extremity is commonly 

pointed; in one or two specimens, rounded. The anterior ear is rounded, moderately well 

developed, usually much higher than long, though in a single right· valve it seems pointed and 

about as long as high. The byssal sinus. which separates the ear from the body of the shell is 

faintly .represented by a slight insinuation or constriction of the anterior margin; this obso-· 

lescent byssal sinus is approximately vertical. The length of the ear is fron1 less than onefourth to about one-third that of the body proper. The body of the shell at the umbones 

includes an acute angle, generally 60° or less, very rarely as much as 80°. The beaks protrude a little above the hinge line., and that of the left valve is occasionally a trifle higher than 

that of the right; they are situated between one-third and one-fourth the distance from the 

front. The oblique height or oblique axis of the body is equal to one-fourth to one-fifth the 

oblique width of the body. The forward extremity of the shell is on the ear below the hinge 

line. The anterior margin of the shell inclines at an angle of about 60° from the hinge line. ' 

The ventral margin is deeply rounded, nearly semicircular; the lowest point is about threefifths the length from the front. '"!"'he posterior portion of the· body proper is strongly convex, 

especially in the rn:ore oblique speeimens, in some of which it forms a deeply inflated catenaric 

or parabolic arch; the hindmost extremity is at the interior fifth or sixth, rarely as high as 

the inferior fourth. The posterior hinge is above the hindmost extremity of the body proper. 

B'oth valves are convex, the left valve being almost ventricose. The right valve in all the 

specimens examined is decidedly less convex than the left. The umbones are inflated in both 

valves:-tl!at of the left mu9h more so than the right-and are incurved to the hinge line. The 

point of maximum depth of the shell is situated on the oblique axis of the body in the umbonal 

region, at the upper third or fourth of the height and the anterior third or two-fifths of the 

length; the slope is strongly convex over all the body proper and is a little steeper toward 

the anterior byssal sinus and just behind the beaks. The depth of the left valve varies from 

a minimum of about one~fifth the length of the oblique axis to. a n1axll:num of eight twenty-
188 FAUNA OF THE CHAPMAN SANDSTONE OF MAINE. 

sevenths the oblique length of the· shell; commonly between one-fifth and one-fourth. The 

depth of the right valve is about one-sixth the length of the oblique axis. The anterior ear is 

strongly convex. The posterior wing is flat to concave and is well demarcated fron1 the body. 

in· both valves. The byssal sinus is extremely shallow and indistinct and runs nearly vertical 

to the hinge line. 

The ligamental strip is elongate wedge-shaped, widening posteriorly, and is nearly in the 

plane of the margin of the valves. It is narrow under the umbones and several times wider at 

the posterior hinge extremity. In sculpture casts the surface over the ligamenta! strip is marked 

by five to eight flexuous, narrow radial riblets, which are usually stronger than n,ny of the others 

on the posterior wing, though much finer than the radii on the body of the shell. This ornamentation about the ligamenta! area may possibly represent striations of the ligament, but 

more probably it is surface ornamentation. There is one posterior lateral tooth in each valve, 

very close to and parallel with the hinge line, or inner edge of the ligament. This tooth extends 

about half or occasionally three-fifths the length from beak to posterior tip. The tooth of the 

left valve is underneath the short tooth of the right valve and is longer and stronger, but in 

some specimens a second tooth appears in the right valve, as well developed as that of the 

left valve and below it. The cardinal teeth are represented in the right valve by three or four 

narrow ridges, directed radially slightly posteriorly, and situated in front of the beaks, and by. 

four or five such ridges in the left valve. The anterior muscular scar is situated on the floor 

of the interior, on the ear, 'close under the foremost cardinal tooth, and is deep and s1nall. The 

posterior scar is not impressed. The pallial line is extremely faint, and is slightly constricted 

in the region of the byssal sinus. 

The body proper is covered with 16 to 21 sin1ple radial ribs of rather characteristic appearance.1 The ribs extend from beak to front and rise abruptly fron1 the interspaces, which are 

flat or slightly convex; the interspaces themselves, where convex, have the appearance of 

interstitial riblets. The ribs are low and rounded, almost planicostate; they are wider than 

the interspaces-much wider toward the umbones, but more nearly equal to them toward the 

front. Both ribs and interspaces increase in width below. Rarely the ribs increase in number 

by an interspQ.ce gradually swelling so as to assume the character of a rib. There are in our 

collections no conspicuous concentric strim on the body, but Clarke 2 reports and figures such 

.. strim. Such concentrically striate forms may represent a distinct variety. In the left valve 

the obscure radial ornamentation is continued forward over the byssal sinus and becomes still 

less pronounced on the ear, .though present in all the better-preserved specimens. Six or seven 

narrow, crowded, obsolescent riblets are discernible oh the byssal sinus, and three to five 

extremely faint radial riblets may be observed on the ear in well-preserved external molds; 

but .the dominant ornamentation on the ear and byssal sinus consists of closely crowded, imbricose lines of growth. The posterior wing is distinctly radially ribbed. The riblets on the 

wing are finer, less regular, and less conspicuous than those on the body of the shell. They are 

10 to 12 in number below the hinge line; but above the hinge line, and between it and the 

upper edge of the ligamenta! strip, a sculpture cast shows five to eight additional flexuous 

narrow riblets similar to those on the wing but stronger, though not so strong as those on the 

body. These five to eight ribs seem to represent surface ornamentation rather than ligament 

wrinkles. The wing is also crossed by concentric lines of growth, much stronger than those 

on the body, where they are hardly discernible in the typical forms. In the right valve the 

radial ornamentation is weaker, but distinctly developed on the body and l~ss distinct on the 

wing. The characteristic ribbing on the upper part of the wing over the ligamenta! strip is 

equally well developed on both valves. No radial ornamentation has been observed on the 

ear or byssal sinus of the right valve. 

1 Typically illustrated in Clarke's left-hand figure of Pterinopecten aroostooki (op. cit.). 2 Op. cit., p. 199, right-hand illustration. 
MOLLUSCA. 

A series of specin1ens have the following dimensions: 

Dim,ensions of specimen.~ of Actinopterella m·oostooki. 

Height (mm.). Length (mm.). 

19 

20 

24 

19 

16.5 

25 

28 

26 

24 

26.5 

189 

The principal distinguishing features of this species have ah·eady been indicated. To these 

may be added the peculiar character of the interspaces between the ribs on the bod_y of the shell. 

These inte.rspaces are usuall_y very abruptl_y demarcated from the low, nearl_y planicostate ribs 

and are· co1n1nonly flat; but a few of then1 are slightl_y convex, producing the appearance of 

an intercalated riblet between the broader, principal ribs. Occasionally these convex interspaces develop into mature or nearly :mature ribs. 

Locality: The species is represented in our collections by several dozen specimens from the 

Chapn1an sandstone, west side of Ednmnds Hill, Chapman Township,'Aroostook County, l\1aine 

Ooenlity 1099 M), where it is abundant. Several varieties, based on the variability in obliquity 

of tho shell and on slight n1odifications in ornamentation; n1ay possibly be erected. 

U. S. National Museun1, catalogue No. 59789. 

OomJJa'risons.-A. aroostoolci Clarke 1nay be recognized an1ong the Chap1nan species by its 

peculiar body ornamentation-the radial ribbing continued over the byssal sinus and ear in the 

left valv-e; the radially ribbed wing; the ribs on the wing increasing in strength about the 

ligmnental sti·ip. The radial ribbing. is developed in the. right valve over the ligamenta! 

·strip quite as well as in the left valve, and is present also on the body, though less distinct. 

The species is distinguished fro1n Actinopte'rella textilis (Hall) by its broader ribs and nuwh narrower interspaces, and to so1ne extent also by the character of the intern1ediate riblets, which 

in A. O/roostoolci are developed only in spots on the shell, not regularly, and all ov-er the body. 

AcTINOPTERELLA AI:~oos:rooKr (Clarke) var. ERECTA vn.r. nov. 

Plate XVII, figure 17. 

c£. 1007. Pterinopectl(n aroostooki (pars). Clarke, New York State Mus. Bull. 107, p. 200, left figure only. 

?:1.907. Pterinea edmundi var. subrecta. Clarke, idem, p. 204 (not figured and only incompletely described). 

This shell agrees with ActinOJJterella aroostoolci in the peculiar character of the ornamentation-broad, low, rounded ribs, abruptly demarcated from the narrower interspaces. Son1e 

of the interspaces on the posterior half of the body gradually assun1e the character of internled.iate riblets or ribs. As in ActinoJJterella a1·oostoolci the wing is radially ribbed; this ribbing 

continues forward faintly ov-er the byssal sinus. . The shell is only slightly v-entricose, and the 

un1bones are hardly protuberant.. The variety is easily distinguished fron1 the principal fonn 

by its very slight obliquity, only about 15° or less fron1 the perpendicular, giving the shell a 

nearly vertical, quach·ate expression with the height equal to the length. 

This variety 1nay be identical with the variety subrecta indicated under the Pterinea edmundi 

of Clarke. The latter name represents the more oblique phase of specimens of Actirwpterella 

m·oostoolci. The shells figured as Pt:erinopecten aroostoolci by Clarke are a trifle less oblique than 

most of the specitnens at Edmunds Hill. 

Locality: Chapman sandstone, 2! miles west of Presque Isle Stream, Chapman Township, 

Aroostook County, l\1aine; a single specin1en. 

U. S. National Museu1n, catalogue No. 59790. 
190 FA UN A OF THE CHAPMAN SANDSTONE OF MAINE. 

ACTINOP1·ERELLA AROOSTOOK! (Clarke) var. PLANICOSTA var. nov. 

Plate :XVII, figure 13. 

This name is applied to a small left valve, because its ribs are actually flat topped and separ~ted from each other by abrupt narrowgrooves, rarely wider than half the width of the ribs 

and generally mere slits. In its strongly ribbed byssal sinus and posterior wing and in its 

moderate convexity the shell conforms with Actinopterella aroostooki, from which it· appears to 

be only varietally distinct. · 

Locality: Chapman sandstone, Edmunds Hill (locality 1099 C 1 ), Chapman Township; 

Aroostook County, Maine. 

U.S. National Museum, catalogue No. 59791. · 

AcTINOPTERELLA CONCENTRICA sp. nov. 

Plate XVII, figure 12. 

?1907. Pterinea cf. P.jasciculata (notGoldfuss). Clarke,. New York State Mus. Bull.l07, p. 204, figs. 

Lower Devonic: Presque Isle Stream, Chapman Plantation, Aroostook County, Maine. 

An imperfect small left valve in the United States Geological Survey collections from the 

Chapman sandstone of Edn1unds Hill represents an interesting species, easily recognizable !rom 

its peculiar ornamentation. which is characterized by well-defined concentric raised lines on the 

body of the shell, particularly in the wide interspaces between the ribs. These concentric lines 

are also developed across the ribs, though somewhat less strongly, producing a crenulating or 

imbricating effect. The radial lines are low, rounded, and far apart, especially in the lower 

portion, where they are separated by interspaces two or three tjmes their width. In most 

of these interspaces another intermediate _line is developed, and in several specimens there is, 

as in A. textilis (Hall), a still finer, hardly discernible line between the principal an~ intermediate 

lines. There are 16 to 20 principal radial lines on the body; they are somewhat more crowded 

on the posterior portion near the wing. Ten or twelve of these lines form the principal ornamentation of the main mass of the body. The posterior wing has faint radial ribs that become 

a little stronger over the region ·of the ligamental strip. 

Among the other char.acters of this fossil are its moderate ventricosity; a very long, shallow, 

ventral margin; large umbonal angle, between 60° and 80°; slight obliquity, only 25° from the 

perpendicular; and alate wing with pennate extren1ity, which extends, in the specim~n exmnined, beyond the hindmost point of the body. The type shell is of diminutive size and is 

incomplete anteriorly. From the beak to the hinge extremity, exclusive of the anterior end, 

the length is 12.2 millimeters; the height of the shell is 10.3 J;Uillimeters. 

Locality: Chapman sandstone, Edmunds Hill (locality 1099 M), Chapman Township, 

Aroostook County, l\1aine. · 

U.S. National Museum, catalogue No. 59792. 

Comparisons.-The above description, drawn up in the winter of 1906, reads almost as if 

it were based upon the specimen ·figured by Clarke as Pterinea cf. P. fasciculata (not Goldfuss's 

species, which is the genotype of Cornellites). Clarke's specin1ens, which apparently represent 

the same species, were obtained from Presque Isle Strea1n, and differ slightly from the typical 

A. concentrica, being more oblique and having a narrower umbonal angle. 

This species somewhat resembles Actinopterella aroostooki in the low, radial ribs, with 

abruptly marked interspaces in the ribbed wing and strong ribbing over the ligamenta! area, 

and, as shown in Clarke's figure, in the radial ribbing on the body of the right valve. It differs 

from A. aroostooki in the much more distant ribs, more profuse development of interstitial 

riblets, and especially in the much greater development of concentric lines on the body. These 

lines in typical A. aroostooki are rarely discernible. The outline also appears to ·be somewhat 

different,· for A. concentrica has a longer and shallower ventral margin. In the widely separated 

radial ribs, and particularly in· the development of finer interstitial riblets, the ornamentation · 

is very much like that of Actinopterella textilis (Hall); 1 the two forms also agree in outline, 

. 1 Hall, James, Paleontology of New York, vol. 3, p. 288, 1859; compare especially Hall's pl. 52, fig. 9. 
MOLLUSCA. 191 

broad shallow ventral margin, etc., but A. concentrica is a much smaller shell, and its concentric lines on the body a.re quite characteristic. Nevertheless A. concentrica may prove to 

be only a variety of A. textilis (Hall). 

AcTINOPTERELLA TENUIRADIATA sp. nov. 

Plate XVII, figure·18. 

1907. Pterinea mainensis (pars). Clarke, New York State Mus. Bull. 107, p. 201, lower right-hand ~gure only. 

Lower Devonic: Telos Lake dam and Moosehead Lake, 7 miles north of IGneo, Somerset County, Maine. 

This is the only species of Actinopterella which has been found in the Moose River sandstone 

fauna of Somerset County, :Maine. ·In this fauna, as contrasted with the late Silurian marine 

faunas of southern Maine and the late Helderbergian Chapman fauna, the genus Actinopterella 

is rm·e, and the present species is represented by only a single left valve. The species resembles 

·· A. radialis, of the Chapman fauna, in its prominent ventricosity, obliquity, and vertical or 

posteriorly directed byssal sinus, .but it is distinguished by the very fine and· more numerous 

radial riblets or lines on the body. 

Tho type and only speeimen is very oblique; the oblique axis is inclined at an angle of 

about 45° with the hinge. Height less than the length; incomplete posteriorly; total length 

prob{l.bly about 33 millimeters or 1! times the height. Greatest height far back at the posterior 

third. I-Iinge line long, continuously straight on .both sides of the beak, and equal to the 

greatest length of the shell. Anterior end rounded; posterior end acutely pointed. The 

posterior wing in the left valve (right valve unknown) is large, concave, approximately in the 

plane of the margin of the shell, and distinctly demarcated from the body. The posterior 

margii1 of the wing is deeply concave,· the lower portion directed upward and forward, the 

upper portion directed backward at an an~le of about 65° or more with the hinge line. The 

anterior ear is well developed, rounded, slightly higher than long. The byssal sinus which 

separates the ear from the body of the shell is well develop.ed, extends downward ·vertically 

or 11 trifle posteriorly, and produces a long constriction of the anterior margin. The body 

of the shell includes at the umbones an angle of 45° or less. The beaks protrude somewhat 

above the hinge line ·and are situated at the anterior one-fourth the length of the hinge line. 

The oblique height or oblique axis of the body is a trifle less than twioe the oblique width of 

the body proper. rrhe forw~l!'d extremity of the shell is on the ear, just below the hinge line. 

The anterior mm·gin includes an angle of 45° to 50° with the hinge line and is essentially parallel 

with the oblique au-x:is. The ventral and posterior margins of the body are deeply convex. 

Ventrul extremity far back, at the posterior third; posterior extremity of the body below the 

midheight. Hinge extremity is directly over the posterior extremity of the body or slightly 

faither back. The left valve is strongly ventricose. The umbo, the body of the shell, and 

the anterior ear· are highly convex, inflated. The posterior wing is abruptly depressed fron1 

the body, is concave, and. lies nearly in ·the plane of the margin of the shell. The. point of 

mn.xi1num depth is on the oblique axis, slightly above the midheight .. The depth of the left 

vnlve, 7 millimeters, is equ11l to more than one-fourth the height. The byssal sinus is well 

developed on the surface, where it is of moderate depth, but it hardly insinuates the front 

margin. 'l'he ligament is inn. narrow semicylindrical escutcheon, which does not appear to be 

\winkled or striated in the specimen exan1ined except just back of the umbones, where a 

couple of striations are discernible. The ligamenta! strip is nearly in the plane of the margin. 

Cardinal teeth not observed. Posterior lateral tooth just below the. ligament; single in the 

left vnlve, deep, rigid, extending to the posterior three-fourths the length of the hinge line. 

Anterior muscular scar small and deep, situated on the floor of the. anterior of the valve, in · 

front of the umbones, underneath the place of the foremost cardinal tooth. The posterior scar . 

and pallial line are not impressed. 

Surface ornamentation not very distinctly preserved on the specimen, which is a sculpture 

cast. The ornamentation, so far as it is preserved, consists of very fine, narrow, su bequal 

radial ribl~ts or lines on the· body.. At a distance of 12 millimeters from the umbo, just in 
192 FAUNA OF THE CHAPMAN SANDSTONE OF MAINE. 

front of the middle of the body, there are between four and ·five radial lines in the width of 

1 millin1eter. Ear and wing ornamentation indistinct. 

I-Ieight, 25 millimeters; length, when complete, about '33 millimeters; depth of left valve, 7 

millimeters. 

Locality: Dense blue calcareous Moose River sandstone, Somerset County, :Maine (locality 

1100 A). 

U. S. National Museum, catalogue N 6. 59793. · 

Oomparisons.-As already indicated, the species is most closely related, an1ong the :Maine 

forms, to A. radialis, from which it is distinguished by its very fine, narrower, and 1nore numerous radial lines. Actinopterella tenuiradiata has n1a~y features in common with the 

Bohemian Actinopterella confortans (Barrande) from an equivalent horizon, the Konieprussian. 

The two species agree in the long, narrow, very oblique body, very fine radial lineation, ·ventricosity of the shell, etc.; but the American fossil has more protruding umbones, a larger 

ear, and a longer and shallower byssal sinus. 

AcTrNOPTERELLA sp. [3. 

Plate XXV, figures 17, 18. 

This is a very small shell, about 1.5 centimeters high, nearly erect, with an extraordinarily 

large ear and nearly subcentral beak; right valve convex and usually concentrically st.riate; 

rarely marked with a few very faint radial lines. The left valve is strongly ribbed ov~r the body. 

The wing of the left valve has a few radial ribs. The radial ornamentation continues faintly 

over the sinus but is not detected on the ear. The shell is ventricose. The byssal sinus is well 

developed and, in the right valve, is accompanied by a deep notch. This small species, which 

may be called Actinopterella sp. [3, closely resembles A. aroostooki in the peculiar character 

of the ribbing on the body of the 'left valve and in the subdued extension of the ribbing on the 

wing and over the sinus. It differs from A. aroostooki in its much larger ear, more nearly subcentral beaks, and more nearly erect form; the ligament is highly inclined to the plane of the 

margin, and the ornamentation over the region of the ligament is faint. 

Locality: Chapman sandstone, Presque Isle Stream, at end of Tweedy road (locality 1099 

A), Aroostook County, Maine. 

U. S. National Museum, catalogw3 No. 59794. 

AcTINOPTERELLA sp. r· 

Plate XXIII, figures 3, 7. 

This shell, which is represented by crushed and imperfect specimens, may possibly be the 

mature stage of Actinopterella sp. {3, which it resembles in ornamentation, ligalfiental structure; 

and ventricosity; it differs, however, in being larger and more oblique and in having the beaks 

n1ore anterior. The height is from 2 to 3 centimeters. Several of these shells show ornamentation similar to that of A. textilis· (Hall)/ but in Actinopterella sp. r intern1ediate riblets occur 

sparsely and irregularly, not uniformly as in A. textilis. The species n1ay be distinguished 

from A. radialis by its more distant ribs and more distinctly ribbed wing. 

Locality: Chapman sandstone, Presque Isle Strean1, at end of Tweedy road (locality 1099 

A), Aroostook County, l\1aine (associated with sp. {3). 

U. S. National Museum, catalogue No. 59795. 

AcTINOPTERELLA sp. a. 

Plate XXIU, figure 2. 

This form is represented by an obscurely marked, strongly oblique ventricose left valve 

distinguished by its fine, profuse ribbing, which is continued over the wings. The umbones 

are broad and protrude above the hinge. The specimen bears some superficial resemblance to 

Actinopterella tenuistriata (McCoy) but is more oblique and has a stronger byssar sinus. 

1 Hall, James, Paleontology of New York, vol. 3, pl. 52, fig. 10, 1859. 
MOLLUSCA. 193 

Locality: Chapman sandstone, 2! miles west of Presque Isle Stream, Chapman Township, 

Aroostook County, Maine. 

U. S. National Museum, cat~logue No. 59796. 

Genus PTERONITELLA Billings. 

Billings 1 defines the genus Pteronitella as· follows: 

Among the fossils collected at Arisaig there are many casts of the interior of several species congeneric with Avicula 

retrojlexa (Risinger). These show that in front of the beaks there are several small anterior cardinal teeth and that 

close beneath the hinge line there are several more or less elongated posterior teeth. This arrangement is quite different 

from that of both A vicula and Pterinea, to which these shells are usually referred. There is a strong anterior muscular 

impression, and the whole structure of the hinge resembles closely that of Cyrtodonta. 

Prof. McCoy has noticed these teeth in his description of P. retrojlexa (Paleozoi(:! fossils, p. 262) but did not seem 

to think their structure of generic importance. I propose to separate P. retro.flexa and others of similar structure from 

Pteri.nea and to place them in a new genus, Pteronitella. 

~rhis genus is of interest because of its wide distribution and, so far as known, rather small 

geologic range. As stated by Billings, the genus was· erected in 1874 for the species Avicula 

retrojlexa (W ahlenberg), to which Billings added three similar species from the Ludlow faunas 

of Arisaig, Nova Scotia. Barrnnde defined three Bohemian species of the Wenlock Aymestrian, 

etage E 2 , as probably belonging to Pteronitella, but the genus appears to have been n.eglected 

by later authors until Clarke 2 recognized it in the faunas of Dalhousie, New Brunswick, and 

Aroostook County, Maine. Indeed, although both Billings and Barrande used the generic 

name Pteronitella it was not recognized in conchologic manuals. In 1899 Philippi,3 in calling 

attention to so1ne discoveries connected with the hinge structure of the genotype, calls the 

fossil Pterinea retrojlexa. Three years later Reed 4 described under the name Pterinea condor 

a typical Pteronitella, neglecting to notice the existence of the name Pteronitella. 

As neither Billings, Barrande, nor Clarke has given a complete description of the genus, 

the following diagnosis is proposed: · 

Pterinoid shells, with right valve less convex than the left but apparently not becoming 

resupinate in front; body of the shell erect; surface concentrically striate; small auricle and 

very large wing distinctly developed; the marginal sinus below the auricle usually very faint 

and small, occasionally indistinguishable; the anterior margin frequently continuing convex up 

to the hinge line, but in such specimens there is a distinct auricular expansion in advance of the 

umbones. The posterior wing is alate and well developed; the posterior margin sigmoidal, but 

never very deeply so. The lack ·of obliquity is characteristic of the typical members of the 

group. The shells are quadrate:, or more frequently transversely elongated, forming an inverted 

oblong trapezoid. The left valve varies from depressed to moderate convexity, and is rarely a 

little gibbous; the right valve is convex, typically less so than the left; it varies from depressed 

convexity to nearly flat, but so far as known does not become concave in front. The ligammital 

area is broad, striated; continuous in front of and behind the beaks. Both cardinal and posteriOI·lateral teeth are developed; the latter are situated nearly parallel with and but little if at 

all removed from the hinge line. The cardinal teet~ are narrow radial ridges, four or five 5 in 

number in the left valve, one le::;s in the right. The foremost one is the stronger and inclines 

downward and slightly forward, the others incline slightly backward. The cardinal teeth are 

situated in front of the beaks on the hinder portion of the auricle. The posterior lateral teeth 

I Billings, Elkamib, Paleozoic fossils, vol. :,!, pt. 1, pp. 141-144, pl. 9, figs. 5, 6, 7, 1874. Avicula (Pterinea) retrojlexa (Wahlenb.\)rg) is the genotype. Billings described three species from Arisaig-two transversely elongated, oblong forms, P. venusta and P. oblonga, and· one nonelongated, 

quadrate form, P. curta. 

2 New York State Mus. Bull. 107, pp. 210-213, 1907. 

a Philippl,oEmil, Ueber dn.s Schloss von Pteri11ea retroflexa Wahlenberg's sp.: Deutsch geol. Gesell. Zeitschr., vol. 51, pp. 181-183, April, 1899. 

~ Reed, ]~. R. C., Woodwardian Museum notes; Salter's undescribed species: Geol. Mag., 2d ser., decade 4, vol. 9, p. 147; pl. 7, figs. 6, 7, 1902. 

6 Billings (op. cit., p. 142, pl. 9, fig. 5b) describes and figures four cardinal teeth, but his figure shows four teeth in the left valve and three in 

tho right. Phillppihns observed four tooth sockets in the left valve of the typical specimen of P. retrojlexa (Wahlenberg), from the sandy crinoidal 

llmestono or :Mow1t Hoburg, Gotland. The foremost tooth or socket is the stronger and is vertical or inclines slightly forward; the others are 

directed backward, as also illustrated and described by Billings. Philippi states that there were five cardinal teeth in the left valve of his Gotland 

specimens and four in the right. · 

50245°--~0.89--16----13 
194 FAUNA OF THE CHAPMAN SANDSTONE OF MAINE. 

are narrow, septa-like ridges, close under the hinge line/ and not oblique nor far removed from. 

it. There is usually one in the right valve, inserted between two .in the left valve; 2 the lower 

tooth in the ieft valve is stronger than the upper, which is also smaller and shorter and, indeed, 

in some specimens is absent. Rarely there are two laterals in the right valve and three in the 

left. In one species, P. cometula Barrande, there are several postlateral teeth, all situated 

close under the hinge line, and th<3 upperm.ost is the strongest. The posterior lateral teeth 

extend usually not more than half the distance from the umbones to the posterior hinge extremity. Muscular scars two; the anterior scar small, deeply impressed (bifid, according to 

McCoy), and situated on the auricle, in,advance of the rostral cavity; the posterior scar is large 

and very feebiy impressed, and is situated mainly or entirely on the wing. Shells thick; structure unknown. Ornamentation, concentric strim, frequently lamellose, especially on the wing; 

no radial ornamentation except very rarely faint radial lines or scratches. 

Geologie range, early, middle, ancllate Silurian (from the May Hill to the Upper LucllowDowntonian faunas) of Europe and An1erica; unknown in the Ordovician; of doubtful occurrence in the lowest Devonian of Germany. · 

The following species are referable to the genus Pteronitella as above defined: 

1. Pterinea retrojlexa. Wahlenberg, Petrificata tell'uris svecame examinata: Soc. reg. sci. Upsala Acta, vol. 8, p. 57, 

1821. Sandy crinoidallimestone (Silurian): Hoburg, island of Gotland. See also Hisinger, Wilhelm, Lethma 

svecica seu Petrificata svecim iconibus et characteribus illustrata, p. 57, pl. 17, fig. 12, Hohinm, 1837; Philippj, 

Emil, op. cit. Hisinger referred the species to the Liassic and Oolitic. The shell currently identifiable with 

Wahlenberg's species occurs in extreme profusion in the Silurian sandy crinoidallimestone of Hoburg. 

?2. Avicula whitfieldi. Foerste, Fossils of the Clinton group in Ohio and Indiana: Ohio Geol. Survey, vol. 7, p. 558; 

pl. 37, fig. 5, 1894. Clinton: Todds Fork and Wilmington, Ohio. 

3. Pterinea sp. Kindle and Breger, Paleontology [of the Niagara of northern Indiana]: Indiana Dept. Geology and 

_Nat. Res. Twenty-eighth Ann. Rept. (for 1903), p. 448, pl. 10, fig. 8, 1904. Niagara or Guelph: Delphi and 

Wabash, Ind. · 

4. Aviculasubplana. Hall, Paleontology of New York, vol. 2, p. 283, pl. 59, figs. 3a, 3b, (not fig. 3c), 1852. Rochester 

shale: Lockport, N. Y. 

5. Avicula naviformis (pars) (not Conrad). McCoy, British Paleozoic rocks and fossils, p. 263, 1855. Wenlock limestone: Dudley, Staffordshire. [Conrad's species is the New York Helderberg (Coeymans limestone) fossil. He 

incidentally mentioil.s the same species as occmring at Dudley, England.] 

6. Posidonomya? rhomboidea. Hall, op. cit., p. 284, pl. 59, fig. 5,·Niagara group: Lockport, N.Y. 

7. Pterinea condor (Salter). Reed, Woodwardian Museum notes; Salter's undescribed species: Geol. Mag., 2d ser., 

decade 4, vol. 9, p. 147, pl. 7, figs. 6, 7, 1902. Lower Ludlow: Dudley, Staffordshire. 

8. Pterinea subplana (not ilall?). Clarke and Ruedemann, Guelph fauna in the State of New York: New York State 

.Mus. Mem. 5, p. 49, pl. 5, fig. 4,1903. Guelph dolomite: Rochester and Shally, N.Y. 

9. Avicula comes. · Barrande, Systeme silurien du centre de la Boheme, pt. 1, vol. 6, pl. 223, box I, fig. 5, 1881. 

10. Avicula cometula. Barrande, idem, pl. 356, figs. 1-7. 

11. Avicula dispersa. Barrande, idem, pl. 223, box I, figs. 3, 4. 

12. A1;icula explanata. Barrande, idem, pl. 224, box III. 

13.' Avicula inclinata. Barrande, idem, pl. 222, box I, figs. 6, 7. 

14. Avicula jacens. Barrande, idem, pl. 223, box I, figs. 1, 2. 

15. Avicu~a reinjormis. Barrande, idem, pl. 225, box VIII.. 

16. Avicula tristis. Barrande, idem, pl. 224, box IV. 

Nos. 9-16 from etage E2 (equivalent of Aymestry of England and Guelph of America), Bohemia. 

17. Pterinea retrojlexa (Wa~lenberg) var. gamma (not=Avicula erecta Conrad). McCoy, op. cit., p. 262, pl. 1, I, fig. 8. 

Upper Ludlow: Laverock Lane. Tilestones: Horeb Chapel, Llandovery, South \Vales. Avicula erecta Comad, 

which was identified by McCoy as a form of Pterinea retrojlexa, equals Glyptodesma erect'um. McCoy also regarded 

Avicula demissa Conrad and A. ampliata Phillips as forms of P. retrojlexa, but these shells a1·e oblique, have a. 

resupi:Q.ate right valve and oblique pos~erior lateral teeth, and belong to the genus Pterinea Goldfuss s. str. 

1 McCoy (British Paleozoic rocks and fossils, p. 262, 1855) states that the posterior lateral tooth in P. retrojlexa diverges "slightly" from the 

hinge line, and Billings (op. cit., pl. 9, fig. 7) figures a very slight divergence in P. oblonga, but the teeth are not oblique to nor distantly removed 

from the hinge line, as they are in Pterinea lcevili Goldiuss, Cornellites flabella Conrad, and Follmannella mainensis, in which the teeth are situated 

at or near the inner botmdary of the wing, where the wing meets the body of the shell., In Pteronitella, as in Actinopterella, the posterior lateral 

teeth have not yet migrated inward away from the hinge. 

~ Philippi records two in the left valve of the typical Gotland species P. retroflex a (Wahlen berg). McCoy describes·" two slender posterior 

teeth about two-thirds the length of the hinge line," and his only figure which shows dentition (op. cit., pl. 1, fig. 8) i.ridicates one posterior lateral 

in the right valve. Billing~ (op. cit., p.l42) describes two lateral teeth in the right valve and one in the left in P. venusta, but his figures (pl. 9, figs. 

5, Sa, Sb) show just the reverse, one in the right valve and two in the left, with the upper tooth in the left valve more weakly developed than the 

lower tooth. 

-~ -
MOLLUSCA. 

18. Pterinea retroflexa (Wahlenberg) var. beta (cf. Avicula naviformis Conrad). McCoy, idem, p.-262, pl. ~~ I, figs. 9·, 

10. Upper Ludlow: Kirby Moor, Kendal, )Vestmoreland; also Hall End in the Malveri1s, and· nea.r Usk, 

according to Sowerby (Mmchison, R. I., Silmian system, pp. 609-610, pl. 5, fig. 9, 1839). 

19. Pteron'itella ven'usta. Billings, Paleozoic fossils, vol. 2, pt. 1, p. 142, pl. 9, fig. 5, 1874. 

20. Pleronilella oblonga. Billings, idem, p. 143, pl.' 9, fig. 7. 

21. .Pteronilella curta. Billings, idem, p. 143, pl. 9, fig. 6. 

Nos. 19-21 from Moydart and Stonehouse formations: Arisaig, Nova Scotia. 

22. Avicula rectangularis. Sow·erby, op. cit., p. 603, pl. 3, fig. 2. Tilestones: Horeb Chapel, South Wales. 

23. Pteronitella passer. Clarke, Some newDevonic fossils: New York State Mus. Bull. 107, p. 212, figs., 1907. Lower 

Devonic: Dalhousie, New Brunswick. Pteronitella Mrundo Clarke, from the same locality, is a Paheopinna. 

'l'he Chapman PteroniteUa peninsttlm Clarke equals Actinopterella 'radialis (Clarke). 

24. Pteronilella quadrala sp. nov. Chapman sandstone: Aroostook County, Maine. 

25. Pterinea lmvis Goldfuss var. prrecurso1·. Frech, Die devonischen A viculiden Deutschlands: Abh. geol. Specialkarte 

Preussen, vol. 9, pt. 3, p. 93, pl. 2, figs. l4-15b; pl. 9, fig. 10, 1891. Siegen graywacke and Tamms quartzite: 

Rhenish province, Germany. The shells figured on pl. 2, figs. 14-15, from the Siegen graywacke of Unkel, are too 

oblique for a Pteronitella and resemble internal molds of an Actinopterella. 

26. Pterinea aff. P. lm'vis (not Goldfuss). Drevermann, Die Fauna der Untercoblenzschichten von Oberstadtfelcl bei 

Daun in cler Eifel: Palaeo:J:ltographica, vol. 49, p. 82, pl. 9, fig. 17, 1902. Lower Coblenzian: Oberstadtfeld, near 

Daun, in the Eifel, Germany. 

27. liiopteria browni. Clarke, Ti1e Paleozoic faunas of Para, Brazil; Devonian Mollusca: Mus. nac. Rio de Janeiro Arch., 

vol. 10, pl. 5, fig. 13, 1899 (author.'s English ed., p. 48, 1900). Lower Coblenzian: Rio Maecuru, Para, Brazil. 

The species differs from ]~iopteria in bei11g erect and in having t~1e posterior scar on the wing, as in Pteronitella. 

Many species of Pteronitella have been referred by recent authors to Pterinea on account 

of the presence of the broad ligan1ental area, deep anterior muscular i1npression, cardinal and 

posterior teeth, and concentric ornmnentation. In the last feature they conforn1 with Pterinca 

s. str. (P. lcevis Gold fuss). Pteronitella Billings differs from Pterinea Goldfuss in several 

respects. 1'he teeth in Billings's genus, unlike those of Pterinea lcevis, Pterinea demissa Conrad, 

and Pterinea ampliata Phillips, are close under the hinge line, as in Actinopterella. In the 

s1nooth shells constituting the true Pterinea the posterior lateral teeth are very oblique to the 

hinge line nnd are situnted on the inner portion of the wing near the junction of the wing with the 

body. As another distinction may be Inentioned the erect expression of Pteronitella. Pterinea 

is oblique, and this distinetion in external outline will permit the ready reference of shells to 

Pteronitella when the internal featul''es are unknown. A third distinction lies in the fact that 

whereas the right valve of Pterinea is always depressed and resupinate (slightly convex on th~ 

mnbones, concave below), the right valve of Pteronitella is frequently rathe1~ convex, generH.lly 

decidedly less convex than the left valve, though apparently not resupinate. 

It is unfortunate that no right valves of typical Pteronitella are at hand for exmnination. 

The right v11hre in sever11l species has been described as "depressed," a term also applied by 

authors to the right valve of Pterinea. }lowever, it is important that a distinction be 1nade 

between "depressed" valves which are depressed-convex throughout and those which are 

resupinate, having a" double curvature," convex on the umbones and concave below, as in the 

Pterinea groups. I mn o:f the opinion that the right valve of Pteronitclla is convex and not 

resupinate, for right vn.lves wherever they have been figured are shown either depressed-convex 

or strongly convex, never resupinate. If this opinion is well founded the persistently resupinate 

chn.rn.cter of the right valve of Pterinea will be recognized, in strong contrast to the nonresupinate 

right valve of Pteronitella and Actinopterella. 

The .oblong forms of :Pteronitella, like P. naviforme (Conrad), P. venusta and P. oblonga 

Billings, P. condor (Sn.lter) Reed, and P. retrofiexa (vVahlenberg), bear a certain resemblance in 

their transverseQextension to l\1cCoy's genus Pteronites. Unfortunately :McCoy's types are not 

well known. In the New York Upper Devonian shells referred to Pteronites by Hall 1 (P. profundus, P. rostratus, and P. inoptatus, to which should probably be added Leptodesma aliforme 

Fiall, L. extenuatum }!all, and the right valve figured on his plate 90, figure 20 (not fig. 19), as 

Leptodesma hector) the posterior scar is nnlCh larger than in Pteronitella and is situated nutinly 

or entirely on the body, instead of .on the wing, as in Pteronitella., Hall's Leptodesma aliforme 

shows a posterior lnteral tooth in the right valve close to the hinge line, in this respect con1 Hall, Jrunes, l'aleontology of New York, vol. 5, pt. 1, vol. 1, pp. 237-239, pl. 22, figs. 24-27; pl. 87, fig. 5, 1884 . 

. . 
196 FAUNA OF THE CHAPMAN SANDSTONE OF MAINE, 

forming with Pteronitella. The right valve is "flat" below, depressed-convex in the middle, 

and more ·decidedly convex on the umbones. All these shells occur in the higher Chemung 

of Tioga and Bradford C()unties, Pa., and Allegany and Cattaraugus counties, N. Y. It is 

apparent that they are merely extreme forms of the shells called Leptodesma by Hall, but 

whether these forms ought to be referred to the Pteronites of McCoy is by no means certain. 

Hall's shells also differ from Pteronitella in the extreme obliquity of th.e anterior margin, which 

gives them a superficial aspect like that of Aviculopinna. Pteronites McCoy lacks the broad, 

striated, ligamenta! area of Pteronitella, and has only a single cardinal tooth under ~he beak of 

the right valve, in which respects it is decidedly distinct. The well-developed anterior muscular 

scar situated on the auricle in Pteronitella has never been observed in P.teronites; indeed, 

McCoy describes Pteronite.s as wanting the anterior adductor impression. In Hall's species 

Leptodesma aliforme the pallial line extends toward the rostral cavity, as in several other 

species of Leptodes1na and in the Aviculidre, and not to the auricle, as in the Pterineas. If the 

anterior scar is lacking in Pteronites and Leptodesma, or is very feebly developed and is 

umbonal, as seems probable, this character will remove McCoy's genus Pteronites, as well as the 

Leptodesma, to the monomyarian Avicula and its allies. The relations of Pteronitella, on the 

other hand, are decidedly with the heteromyarian Pterinea. 

Pteronitella might be confused with Leiopteria I-Iall, with-which it agrees in the concentric 

ornamentation, in having the right valve convex but less so than the left, and in having posterior 

laterals (usually not discernible) close under the hinge line; but Leiopteria is easily distinguished 

from Pteronitella by its characteristic obliquity. Leptodesma Hall is generally still more 

oblique. 

Palreopinna Hall bears some general resemblance in outline to the typical Pteronitellas 

(P. condor (Salter) Reed, P. retrofiexa (Wahlenberg), P. naviforme (Conrad) and P. venusta 

and P. oblonga Billings), but differs from then1 in the persistence of radial lineation; in the 

typically thin linear ligamenta! area and, especially, in its truncate anterior margin, which is 

entirely. devoid of auricle and which has the beaks terminal. 

Some discussion has arisen regarding the relative values of the names Pteronitella Billings, 

1874, and Mytilites Wahlenberg, 1821. · The name Mytilites Wahlenberg can have no value in 

zoologic nomenclature, as it was used in a very general way by W ahlenberg to include practically 

~ll fossil lamellibranchs mnbedded in solid rocks. Wahlenberg divided Recent bivalve shells 

into Mytili, Ostrei, and Anomire, and recorded Mytilus edulis and Mytilus ]Jholadis, two now 

living shells, from the glacial beds of Uddevalla. 1 It is apparent that Wahlenberg included 

under the name Mytpus all the dimyarian and heteromyarian lamellibranchs-in fact, all the 

lamellibranchs except the Ostreidre. The "Mytili" embedded in the solid rocks Wahlenberg 

called "Mytilites,"' so that the name has a significance similar to that of Anon1ites as applied by 

early authors to the fossil brachiopods, and this significance is certainly unlike and more 

general than that of a, generic ·name. lf1ytilites refroflexus is the second species described by 

Wahlenberg, who records it fron1 southern Gotland in calcareous and arenaceou~ beds. The 

first species of Mytilites describerl is lf1ytilites edulis affinis W ahlenberg, fron1 the graptolite) 

shales of Westrogothia, so that even if the name Mytilites were restored, which it ought not to 

be, it could not be applied to Pteronitella retrofiexa, but would have to be used for the "lffytilites 

edulis ajfinis" of W ahlenherg. · 

PTERONITELLA QUADRATi\ sp. nov. 

Plate XXIII, figure 5. 

Outline erect, quadrate. Height; 23 millimeters, nearly equal to the length ("width"), 

which is 241 millimeters. Greatest height near the mid length; greatest length at the inferior 

two-sevenths. Hinge line long, slightly less than the length of the shell. The umbones are 

situated at the anterior fifth or sixth of the length of the h;nge, are rather full, incurved, and 

. prosogyrate, and protrude slightly above the hinge line. The anterior margin is sigmoidal and 

erect. In front of the umbones the anterior margin is convex, producing in the outline the 

appearance of a small ear; below this the margin is strongly insinuated by a byssal sinus that 

extends down one-third or two-fifths the height, b~low which the anterior margin along the body 
MOLLUSCA. 197 

of the shell is again convex, in general vertical, and with' the foremost extreniity vertically 

below or rather distinctly in advance of the" auricle." The ventral margin is broad, depressedconvex, and with the lowest point in front of the middle; the margin slightly ascending toward 

the rear and curving into the posterior margin, which turns upward at an angle of about 95° 

with the hinge line. The hindmost extremity of the shell is near the base of the posterior margin, at two-sevenths the height of the shell above the ventral extremity. The posterior margin 

is depressed-convex in the lower part, broadly and faintly concave near the middle, and 

straight and directed slightly forward in the upper part. The left valve is strongly convex, 

especially in the umbones, and is also very full in the body. The subalu.te posterior is indistinctly demarcable from the body. The byssal sinus, though strongly marked in the anterior 

outline, is very faint on the surface, which has here a steep slope. The so-called u auricle" is 

not flattened, but is slightly inclined-more so than the subalate posterior. Although the 

shell as a whole is erect, the gibbous umbones are inclined at an angle of about 20° from the 

perpendicular. The point of greatest depth is between the anterior third and fourth of the 

length. and at the upper third of the height, just- behind the byssal sinus. The depth of the 

left valve is 5 n1illi.meters., or a little more than one-fifth the length. 

The impression of a single, slender, horizontal posterior-lateral tooth is preserved; it must 

have been very close to the hinge line. Above this tooth the specimen is broken away. The 

cardinal margin at the u.mbone is also broken away, so that it is impossible to describe the 

cardinal teeth. ~1uscular scars not preserved. 

Surface concentrically striate, with a few low concentric wrinkles and lamellose varices. 

The varices are n1ost distinct along the ventral margin and along the anterior margin below 

the byssal sinus; the posterior is faintly striate, as is also the region of the byssal sinus. The 

concentric striations are oecasionally rather regular, almost bellastriate over the body, but are 

rather faint; they are still fainter on the posterior. 

Locality: Chapman sandstone, on Presque Isle Stream near the Tweedy road (locality 1099 

L); Chapman Township, Aroostook County, Maine. 

U.S. National Museun1, catalogue No. 59797. 

Oom1Jarisons.-The distinguishing features of the species are the erect quadrate outline, 

with the height very nearly ~qual to the length; anterior margin vertical or protruding, not 

diagonally retroceding; anterior or byssal sinus well developed in the outline; posterior n1argin 

faintly or hardly at all signwidal, the upper part reaching upward and slightly forward to the 

hinge. Its quadrate outline distinguishes it from the transversely elongated species of Pteronitella, such as P. retrofiexa (Wahlenberg), P. navijorme (Conrad), P. condor (Salter) Reed, 

P. venusta and oblonga Billings, P. cometula (Barrande), etc. P. quadrata belongs to a group 

of quadrate species of Pteronitella in which the height is about equal to the length; includes 

Pteronitella curta Billings, P. rectangularis (Sowerby), P. erecta (McCoy), etc. From the last two 

species P. quadrata differs in having the anterior margin vertical instead of diagonally retro-

. ceding. From the Arisaig P. curta Billings, which it closely resembles, P. quadrata differs in 

having the ventral margin less bellied down, in being more quadrate instead of semielliptical, 

in having the posterior margin sigmoidal-though only slightly so-and directed upward and 

forwru·d; m1d in being smaller. P. quadrata bears a close resemblance in outline and convexity 

to the Posidonomya? (Pteronitella) rhomboidea Hall, of the Niagara, but differs from it in having 

a well-developed byssal sinus in the upper anterior margin, which, in P. rhomboidea, is convex 

throughout. In the quadrate outline, vertical anterior margin, byssal sinus, and slightly 

auricular expansion the shell :resembles Leiopteria (Pteronitella?) browni Clarke, but that species 

is much larger and, unlike P. quadrata, has the upper part of the wing extended posteriorly. 

Gen.us MEGAMBONIA Hall, 1859. 

The genus Megambonia was founded by Hall 1 in 1859 to include eleven species from the 

Helderberg group, two from thB New York Oriskany, and one from the "Corniferous" limestone. 

These fourteen species comprise a heterogeneous assemblage including species referable to 

V ru1ux:emia Billings, Leiopteria Hall, and other genera. 

I Hnll 1 Jrunos1 Now York Stnto Cab. Nat. Hist. Twelfth Ann. Rept., p. 12, 1859: Paleontology of New York, vol. 3,pp. 272 et seq., 1859 (1860?). 
198 FAUNA OF THE CHAPMAN SANDSTONE OF MAINE. 

Of the eleven species of Megambonia described by Hall from the Helderberg, only two 

appear to belong to the genus, namely, M. ovoides and M. rhomboidea Hall. M. mytiloidea and 

M. obscura are species of Plethomytilus or some allied mytiloid; M.. aviculoidea and the Oriskanian M. lamellata belong to the genus Leiopteria; M. lata js a species of the CypricarditesCyrtodonta group; M. cordiform is and M. ovata appear to be species of V anuxemia, though 

they have been regarded as Mytilarca or Plethomytilus by Miller an·d by Hall. Megambonia 

suborbicularis and M. spinneri may also possibly belong to V an~-x:emia. Megambonia oblonga 

Hall is the genotype of the new genus Preavicula described on page 205. . 

The genotype of Megambonia is M. cardiijormis (Hall)/ from the "Corniferous" limestone. 

Hall separated. Megumbonia from Ambonychia because it has a well-developed anterior 

lobe or auricle, which is absent in Ambonychia; the auricle is separated frmn the body by a 

distinct byssal sinus. The anterior mu~cular impression is distinctly developed, fairly large, 

and situated on the auricle. In the ambonychioids the anterior muscular impression is either 

lacking or indistinct and minute, the pallial line terminating in the rostral cavity. Megambonia 

is therefore related to the heteromyarian Pterinere, whereas A.mbonychia represents the early 

mo.nomyarian Avicula type. The shells of Megambonia have a characteristic expression easily 

recognized by their subcircular outline; inflated umbones, ventricose, equal valves; rounded 

auricle; wing obscurely developed or lacking; surface typically covered with fine radial line~ 

crossed by concentric lines. In the original diagnosis of the genus given in 1859 Hall laid stress 

on the occurrence of numerous teeth or crenulations on the anterior portion of the hinge line. 

In 1885 this portion of. the description was retracted. 

The original diagnosis of the genus is as follows: 2 

Shell equivalve or subequivalve, inequilateral, subovoid, usually very gibbous in the middle and toward the 

umbones; anterior side often lobed or auriculate, a strong muscular impression occupying a COJ?,siderable portion of 

this portion of the shell; posterior cardinal margin expanded, more or less compressed and frequently alate; hinge 

crenulated on the anterior end; teeth numerous. Surface marked by concentric laminm of growth and often by fine 

radiating strim. The etl.tire structure of the hinge is unknown; and the grouping of the species has been mainly 

determined by external form and marking and the large anterior muscular scar, which is a conspicuous feature in most 

of the species. 

Hall 3 ~esignated Pterinea? cardiijormis Hall, 1843, as the type of the genus. 

In 1885 the generic description was emended.'by Hall 4 to read as follows: 

Shell ,equivalve or subequivalve, very inequilateral, obovoid, body very oblique; anterior end (in two typical 

forms) lobed; posterior large, constituting the principal part of the shell; beaks anterior; cardinal line short; subalate 

posteriorly; umbonal slope ventricose, not defined. Surface marked by fine strim of growth, which in some species are 

crossed by fine radiating strim. Hinge line short; a distinct lateral fold and groove near the postcardinal angle. Ligament internal. · Anterior muscular impression large and strong; posterior \impression large. The type of the genus is 

well marked, and its form and external characters are very distinctive. It does not, however, show the anterior teeth 

or crenulaticns mentioned in the original description. In the third volume of the Paleontology of New York several 

species are described under this designation which further study hasshown not to be congeneric. At tho present time 

the only forms which I regard as strictly belonging to the genus are from th~ Corniferous limestone and Oriskany sand- . 

stone. Those from the Lower Helderberg group require more material for a final determination. 

Hall then designated ~llegambonia cardi~formis, from the "Corniferous" limestone, and 

1.1. bellistriata, from the Oriskany, as characteristic of the genus. These two species are regarded 

by Clarke 5 as identical. Hall also indicated that such forms as M. lamellosa are doubtfully 

referred to the genus. This species is apparently a Leiopteria. 

. In all the American radiostriate shells which conform withM. cardiiformis and ]f. bellistriata 

Hall the posterior wing is rounded and there is no wing nor alation at the hinge extremity, but 

in some of the European species a wing is faintly developed. The occurrence of an internal ligament, as noted by I-Iall, is doubtful, as one of his figures 6 seems to indicate an external ligament. 

One figure of M. striatocostata Giebel given by Barrois/ however, indicates an internal ligament. 

1 Hall, James, Geology of New York, Rept. Fourth Dist., p: 173, 1843. This shell should not be confused with llfcgambonia cordiformis Hall, 

1859, from the Helderberg. 

2 Hall, James, Paleontology of New York, vol. 3, p. 273, 1859 (1860?). 

3 Idem, p. 272. 

4 Paleontology of New York, vol. 5, pt. 1, p. lv, 1885. 

u Clarke, J. M., The Oriskany fauna of Becraft Mountain, Columbia County, N.Y.: New York State Mus. Mem., vol. 3, p. 35, i900. 

o Paleontology of New York, vol. 5, pt. 1, pl. 52, fig. 2, 1885. . 

7 Barrois, Charles, Faune du calcaire d'Erbray: Soc. gaol. Nord Mem., vol. 3, pl. 10, fig. Sa, 1889. 

d-
MOLLUSCA. 199 

The genus Myalinopteria Frech is apparently a synonym of Megambonia Hall. 

Megambonia Han is closely related to the Ordovician genus Prolobella Ulrich,t. agreeing 

in outline, biconvexity, and presence of radial ornamentation. The Ordovici.an shells, however, 

are much smaller; the auricle and the anterior muscular i1npression are proportionately more 

minute than in Megambonia, and the radial lines. are somewhat· different. 

The genus Megambonia Hall as above interpreted includes the following species: 

Jfegambonia thomboidea. Hall, Paleontology of New York, vol. 3, p. 275, pl. 49, fig. 9, 1859. Helderberg group: New 

Scotland, N. Y. 

Megambonia ovoidea. ·Hall, idem, ·p. 276, pl. 49, A, fig. 4. Helderberg group:· New Scotland, N.Y. 

Megambonia parva. Weller, Paleozoic faunas: Paleo!1tology of New Jersey, vol. 3, p. 333, pl. 43, fig. 12, 1903. Dalmanites dentatus zone or Trilobite beds: New Jersey. 

Jfegmnbonia bellastriata. Ha.Ll, op. cit., p. 467, pl. 109, fig. 4. Oriskany: New York. 

Megambonia crenistriata. Clarke, New York State Mus. Mem., vol. 3, pl. 4, p. 35, figs. 15-17, 1900. Oriskany fauna: 

New York; Gaspe, Quebe1c. 

Jfegambonia denysia. Clarke, New York State Mus. Bull.107, p. 216, figs., 1907. Lower Devonic: Perce Rock, Quebec. 

Pterinea striatocosta. Giebel, Die silurische Fauna des Unterharzes, p. 27, pl. 5, figs. 15, 18, 1858. Hercynian: Harz 

Mountains~ The Pterinea. sp. of Kayser (Die Fauna der altesten .Devon Ablagerungen des Harzes: Abh. geol. 

Specialkarte Preussen, vo1. 2; pt. 4, p, 135, pl. 19, fig. 4, 1889), from the Schneck.enberg limestone of the Harz, 

represents this species. The fossil is also recorded and well illustrated by Barrois (Faune du calcaire d'Erbray: 

Soc. geol. Nord Mem., vol. .S, p. 171, pl. 10, fig. 8, April, 1889) from the Erbray limestone of Loire Inferieure, western 

France. 

Myalinopteria alpina. Frech, Die devonischen A v.iculiden Deutschlands: Abh. geol. Specialkarte Preussen, vol. 9, 

pt. 3, p. 139, pl. 18, fig. 1, 1891. Hercynian reef limestone: Wolayer Thorl, Garnish Alps. 

Megambonia cardiiformis. Hall, Paleontology of New York, vol. 5, pt. 1, p. 515, pl. 52, figs. 1-8, 1885. M. bellastriata, 

Jf. crinita, M. denysia, and M. subcardiijorrnis appear to be synonyms. Corniferous limestone: New York. 

Jfegmnbonia subcardiiforrnis Hall= M. cardiiformis Hall. 

(Myalinoptera) crinita (A. Roemer). Frech, op. cit., p. 138, pl. 11, figs. 1-7, Lower Neo-Devonian: Grund and Claus 

Valley, Germany. 

MEGAMBONIA ef. M. CARDIIFORMIS Hall. 

Plate XXIV, figure 4. 

1843. Pterinea? cardiifonnis. Hall, Geology of New York, Rept. Fourth Dist., p.173, fig. 1 (on p.172). 

Corniferous limestone: Clarence Hollow, Erie Comity, N. Y. 

1859. Megambonia cardiijormis. Hall, New York State Cab. Nat. Hist. Twelfth Ann. Rept., p. 13. 

cf. 1859. Megambonia bellistriata. Hall, Paleontology of New York, vol. 3, p. 467, pl. 109, fig. 4. 

Oriskany sandstone: Albany and Schoharie counties, N. Y. 

1885. Jfegambonia cardiiformis. Hall, Paleontology of New York, vol. 5, pt. 1, p. 515, pl. 52, figs. 1-8. 

Upper membe1· of the Corniferous limestone: Clarence Hollow, Erie County, N. Y. 

cf. 1900. Megmnbonia crenistriata. Clarke, New York State Mus. Mem., vol. 3, p. 35, pl. 4, figs. 15-17. 

Oriskany fauna: Becraft Mountain, Columbia County, N.Y. 

cf. 1908. Megambonia crenistriata. Clarke, idem, vol. 9, p. 157, pl. 21, figs. 6, 7. 

Gaspe limestone: Grande G;reve, Gaspe, Quebec. 

No species of Megambonia has been discovered in the Chapman fauna, but in the Moose 

River sandstone fauna of Somerset dounty, Maine, two small specimens of Megambonia have 

been found which, to judge from their outline and convexity, represent two distinct species. 

The larger specimen is identified with Hall's species, thm.~gh it is much smaller tha~ the typical 

New York forms. The smaller specimen, described below as the variety parmuscula var. nov., 

is distinct in outline and convexity and may be a distinct species instead of a variety. The 

specimen identified with Hall's species shows the following characters: Outline subovoid, 

erect. 2 I-Ieight, 27.7. 1nillimeters; length, 26.5 millimeters without the aw.:icle, but the shell 

is proportionately more transverse in the younger stages, as indicated by the lines of growth. 

Greatest height .at the midlength; greatest length just below the midheight at the inf~rior 

three-sevenths. Umbones subventral, directed vertically upward, protruding very slightly 

beyond the hinge line. The hinge line back of the umbones is not preserved but was apparently rounded, convex, short:; its length less than half the height of the shell, declining pos1 Ulrich, R 0., Geology of Minnesota, voL 3, Paleontology, pt. 2, p. 532, pl. 25, fig. 27, 1894. 2 'l'ho shell is arbitrarily oriented as erect. Figures of these shells are usually oriented in an oblique position, which, technically, may be more 

nearly correct, considering tho fact that the two muscular scars ought to be on a horizontal! inc. Practically it is found that comparison of the 

different forms of Mogambon ia is facilitated by orienting the figures w"ith the shell seemingly erect instead of oblique. 
200 FAUNA OF THE CHAPMAN SANDSTONE OF MAINE. 

teriorly at an angle of nearly 30° with the horizontal. . The posterior hinge extremity is convexly rounded, not alate nor pointed. The. posterior margin is strongly and symmetrically 

convex throughout; the hindmost extremity is at the inferior three-sevenths the height or near 

the midheight. · The ventral margin is deeply bellie~ down, :forming with the lower posterior 

and lower anterior margins a symmetrical, semicircular arc or paraboloid. The anterior margin 

is convex, with the foremost extremity ·of the body of the shell at the midheight. The upper 

part of the anterior margin, including the auricle, is' not preserved on the specimen, which 

shows, however, traces of the byssal sinus extending radially forward from the beak. The 

shell is gibbous throughout, a little less so along the upper posterior margin than elsewhere. 

Just below the umbones it is very gibbous. The point of greatest depth is vertically below 

. the beak at the superior third; the depth of the single left valve (7.7 millimeters) is more than 

one-fourth the height (27.7 millimeters). The byssal sinus appears to have been narrow but 

is distinctly preserved on the surface; it extends radially forward at an angle of 35° with the 

vertical. Hinge structure and musculature unknown. Shell very thin; crystalline; colored 

black, probably indicating a high organic content. 

Surface covere.d with undulating concentric wrinkles of growth and a few low, lamellose 

varices, strongest in the middle. These are crossed by very fine radial lines over the entire 

body (the auricle is not preserved). The lines are more strongly developed over the central portion than towttrd the rear. 

Locality: Moose River sandstone between Parlin Pond and Detroit (locality, 1100 A), 

Somerset County, Maine. 

U.S. National Museum, catalogue No. 59798. 

Oompansons.__.:..:The shell is much smaller than either Hall's Megambonia bellistriata, from 

the Oriskany, or his M. cardiiformis, from the "Corniferous." As suggested by Clarke in 

1900, both of these names represent a single species, there being no reliable distinction between 

the Oriskany M. bellistriata Hall and t:q.e "Corniferous" M. cardiiformis Hall. Hall suggested 

that the latter was much more gibbous, which does not seem to be always true, and that the 

byssal sinus is shallower in M. cardiiformis than in M. bellistriata, which is·only generally true; 

one of Hall's figures 1 shows a "Corniferous" M. cardiiformis with a deep and well-marked 

byssal sinus. 

Any distinctions which may possibly exist between Megambonia cardiiformis Hall, from 

the Onondaga, and the so-called Megambonia bellistriata have yet to be proved, so that these 

two names may be regarded as identical. M. cardiiformis is the older name. All the other 

American species of Megambonia, including the Maine shell under discussion, are much smaller 

than Hall's M. cardiiformis, which is relatively of gigantic size. Megambonia crenistriata Clarke, 

from the Oriskany of ·Becraft Mountain, N. Y., differs from Megambonia bellistriata ( = cardiiformis) Hall in being smaller and proportionately broader, and in having a longer, straighter, 

and more distinct hinge line. The other characters mentioned by Clarke-convex auricle, deep 

byssal sinus, coarser strire on the auricle, and crenulations of the strire-are also present on 

the normal Megamboni(t bellistriata ( = cardiiformis) Hall. The distinctive characters of the 

small Becraft Mol.J.Iltain shell appear insufficient to separate it as a distinct species from M. 

bellistriata (=cardiiformis), the greater proportionate breadth in smaller specimens being, 

indeed, the normal occurrence in the immature of these shells. The. ventral margin is much 

less bellied down in the so-called M. crenistriata than is usual in M. cardiiformis, and the hinge 

line is more distinct; but these may be regarded as extreme characters of a single species, the 

Maine specimen here described being intermediate in these respects between the two forms, 

though agreeing with the Becraft Mountain Oriskany shell in small size, as well as in habitatat least so far as habitat is indicated by the same rock (a very hard, fine-grained blue quartzose limestone) and by similar fauna. 

In its small size, outline, and convexity the Maine shell resembles the Helderberg M. ovoidea 

Hall, which has, however, a much less developed byssal sinus .. 

1 Paleontology of New York, vol. 5, pt. 1, pl. 52, fig. 1, 1885. 
MOLLUSCA. 201 

MEGAMBONIA cf. ~f. CARDIIFORMIS var. PARVIUSCULA var. nov. 

Plate XIX, figure 23. 

This small shell occurs with the normal M. cardiiformis above descr~bed in the Moose 

River sn,ndstone fauna of Detroit, Somerset County, Maine. The two speci1nens, though associated, a.re regarded as at least yarietally distinct. The small shell here described is more 

transverse and more nearly subcircular than the typical form; the length (14 milli1neters) is 

slightly greater than the height (12 millimeters). The greatest length of the small variety 

is at the upper third, whereas it is below the, middle in the larger shell. T.he umbones are 

central, directed upward, incurved, hardly if at all protruding ·above the hinge line. They 

subtend an angle of 90° or more. The posterior limit of the umbonal angle is less sharply 

defined than the anterior limit. The ·hinge line back of the ~umbones is short, convex, horizontal; equal in length to a trifle more than the height of the shell (in typical M. cardiiformis 

it is a trifle less than half the height. and declines at an angle of 30° or more). The posterior 

hinge extremity is convexly rounded, decidedly not alate. · The ventral margin is broadly 

rounded and is less deeply bellied clown than in the larger forms. The forward extremity of the 

shell is lower down, being at the inferior third in the variety parviuscula. A deep byssal notch 

or sinus extends fro1n the n1iclheight to a point above the midheight of the anterior margin. 

The byssal sinus 1narks off from the body a proportionately very large, rounded auricle, which 

extends directly above or slightly in advance of the forward extremity of the body; the margin 

rounds off into the hinge line, which continues ascending backward to the umbones. Just 

below the un1bones the shell is tu:mid. The greatest depth is near the midheight at the anterior 

third, not directly below the beak at the upper third, as in the larger normal form. The postumbonal slope is less infl~tecl than the body of the shell. The byssal sinus is definable on 

the surface and extends to the mnbo. 

The characteristic fine lines and strire are ,preserved on the body, but are not definable on 

the ear and posterior slope in the specimen at hand. Concentric strire and undulations cross 

the body, but they are better ~eveloped on ·the auricle, and especially on the postumbonal 

slope. ' 

This little shelln1ay be easily distinguished fron1 the typical form by its minute size, greater 

width, longer and horizontnl hinge line, shallower ventral margin, and the other minor distinctions 1nen tioned above. 

Locality: Moose River sandstone, between Parlin Pond and Detroit (locality, 1100 A), 

Son1erset County, :Maine. 

U. S. National Museum, catalogue No. 59799. 

Family CONOCARDIIDJE Neumayr. 

GE~nus CONOCARDIUM Bronn, 1835. 

?CONOCARDIUl\f DUBIA sp. nov. 

Plate XXIII, figure 1. 

A fantastically ornamented little bivalve is represented in the Chapman fauna by a fragment 

of a right valve. The generic position of the shell is uncertain, but the specific characters are 

conspicuous. The fragment is deeply inflated and shows three strong rounded ribs radiating 

downward fron:i the beaks, with three or four narrower and fainter ribs justback of them. In 

front of the radially plicate portion of the shell is a nonplicated portion of about the same width. 

The hindmost of the radial ribs seems to mark a sort of postumbonal ridge or respiratory angle, 

behind which the shell descends in a deeply inflated, concentl'ically striate slope. The extreme 

postdorsal and anterior portions of the shell are not known. 

The peculiar markings are the most characteristic feature of the shell. 

Locality: Chapn1an sandstone, Presque Isle Stream, Chapman Township, Aroostook 

County, Maine. 

U.S. National Museun1, cu,talogue No. 59800. 
202 FAUNA OF THE CHAPMAN SANDSTONE OF MAINE. 

Oomparisons.-The development of pronounced radial ribbing over a centrally demarcated 

area and the presence of only concentric lines of growth both before and behind the ribbed area 

suggest at first a relationship with the shells commonly referred to the genera Pholadomya 

Sowerby and Pholadella Hall; but the deep inflation, the contour of the surface, and the outline 

indicate a more probable relationship elsewhere. 

The Chapman fragment seems most nearly allied to a group of Silurian species of Conocardium from Gotland 1 and Bohemia, 2 which are characterized by having only a few radial ribs, 

situated near the respiratory angle; the surface only concentrically striate, both anteriorly and 

posteriorly; and -a steeply convex slope just back of the ribs. The Chapman spec!es is, indeed, 

very similar to Conocardium brachypleura (Lindstrom), the Gotland form, but has more numerous 

ribs and a less tumid umbone. The Chapman species differs from the Bohemian Silurian species 

of Conocardium in the character of the ribs and in other features. 

Family PTERIID.tE Meek. 

Genus LIMOPTERA Hall. 

The shells of the genus Limoptera are distinguished fron1 the pterinoids which they superficially resemble by the large, only slightly oblique, nearly erect forms; the anterior ear usually 

small or 'absent; the posterior wing large; both valves frequently convex; radial ribs, if present, 

simple, not fasciculate, in many speciniens obsolescent. The ending of the pallial line in the 

umbonal apex rather than in a more distinct anterior scar, situated on the ear, removes Limoptera from the pterinoids and indicates the affiliation of the genus with the pri1nitive aviculoids. 

The term Limoptera s. str. may be restricted to the more or less radially ribbed shellshaving the 

ear or auricular portion to some extent discernible, as typified by L. macroptera Conrad, the 

genotype. Other shells.which have been called Limoptera may be distinguished from that genus 

in two sections to which the names Myalinodonta and Paropsis Oehlert are applicable. In the 

shells of. both these sections there is not the slightest .trace of an ear, the beaks are not at the 

forward termination of the hinge line, the forward extremity of the body is far in advance of the 

beaks, and the upper anterior margin to the beaks is concave. One of the sections is represented 

by Limoptera semiradiata Frech/ L. bifida (Sandberger)/ L. longialata Drevermann,5 and Myalinodonta normaniana (D'Orbigny) ~ 6 To this section may be applied the name Myalinodonta 

Oehlert, 1881. The last7"named species is the type. It is depressed convex, equivalve, an'd 

radially striate or finely ribbed, and is in some respects a combination of Myalina and Tolmaia. 

An interesting f.eature is the occurrence of a triangular patch under the beak in the horizontally 

striated ligament. A similar feature is figured by Drevermann7 in his Limoptera (~) (nov. subgen.~) n. sp. The occurrence of such a triangular pit in the striated ligamenta! area has been 

utilized by Girty 8 to separate his new genus Limipecten from Aviculopecten. A.similar triangular (cartilage) pit under the umbone in the broadly striated ligamenta! area occurs in several 

species of Lyriopecten Hall 9 (Orbipecten Frech). · 

To Myalinodonta may possibly be added A.vicul,opecten iiwertus Oehlert. 10 

This species is figured with terminal beak and concave upper anterior margin and is jncluded in Limoptera by BarroisY No ear is shown by either of Oehlert's figures, and its absence 

1 Pleurorhynchus brachypleura Lindstrom (Angelin, N. P., Fragmenta silurica, p. 19, pl. 13, figs. 42-46, 1880), from the late Ordovician or early 

Silurian limestones of Dalecarlia, Sweden. 

2 Conocardium correctum Barrande (Systeme silurien du centre de la Boheme, vol: 6, 1881, pl. 203, box IV, figs. 5-12, not figs. 1-4), from the hills 

between Lodenitz and Bubowitz; Conocardium dorsatum Barrande (idem, box V), from Kozel; Conocardium binotatum Barrande (idem, pl. 202, 

box III), from 'Dlauha Hora. · All three species are from the middle Silurian limestones of etage E2. 

s Frech, Fritz, Die devonischen Aviculiden Deutschlands: Abh. geol. Specialkarte Preussen, vol. 9, pt. 3, p. 65, pl. 5, figs. 1-3, 5-8, 1891. 

4 Idem, p. 64, pl. 6, fig. 2. 

~ Drevermann, F., Die Fauna der Untercoblenzschichten von Oberstadtfeld bei Daun in der Eifel: Palaeontographlca, Yol. 49, p. 79, pl. 9, fig. 

12, 1902. 

6 Oehlert, D.P., Documents pour servir a l'etude des faunes devoniennes dans l'ouest de la France: Soc. geol. France Mem., 3d ser., Yol. 2, 

pp. 29-31, pl. 5, 1881. 

1 Drevermann, F., Palaeontographica, voi. 49, pl. 9, fig. 13, 1902. 

s Girty, G. H., New molluscan genera from the Carboniferous: U.S. Nat. Mus. Proc., vol. 27, pp. 722 et seq., pls. 45, 46, 47, June, 1904. 

o Hall, James; Paleontology of New York, vol. 5, pt. 1, pl. 10, figs. 2, 6, 1885. · 

10 Oehlert, D.P., op. cit., p. 26, pl. 4, figs. 2, 2a. 

11 Barrois, Charles, Faune du calcaire d'Erbray: Soc. geol. Nord Mem., vol. 3, p. 175, 1889. 
MOLLUSCA. 203 

would indicate that the species belongs to the more convex group of species of Myalinodonta; 

but in the text Oehlert n1entions a small u ear" on each side of the beak. 

If Myalinodonta should prove to possess a triangular cartilage pit, it may be removed from 

Lin1optera and affiliated with the pectenoids. · · 

The second entirely earlpss group confounded with Limoptera but properly to be dissociated 

therefrom is characterized by the absence of radial ribbing, the body being only concentrically 

striate. This group, the genus Paropsis of Oehlert/ includes Avicula (Paropsis) orbicularis 

Oehlert, Limoptera rhenana Frech, Limoptera gigantea (Follman) Frech, and Limoptera obsoleta 

I-Inll. 2 

Limoptera s. str. will, then, be restricted to strongly convex, radially ribbed limopteroid 

shells in which there is at least some trace of an ear or auriculate expansion in front of the 

umbones and in which the umbones are subterminal, not quite terminal. Some of these shells 

approach some of the fonns of Myalinodonta, but in Limoptera s. str. the ribs are more distant 

and the upper anterior margin more nearly· vertical. 

Paropsis and Myalinodonta occur in the Lower Devonian (Siegen graywacke through the 

Upper Coblenzian) of Gerrnany and France, and a single species of Myalinodonta is recorded 

from the lower Meso-Devonian of France (Calceola or Porsguen shales of Krouzon, near Brest) .:1 

In America Myalinodonta is apparently unlmown and the only species referable to Paropsis 

(Limoptera obsoleta I-Iall) is fron1 the Middle Devonian .(I-Iamilton formation). 

Avicula pauciradiata Hall, 4 from the shaly New Scotland (" Delthyris ") limestone of the 

I-Ielderberg group, Schoharie, N.Y., is a plicated limopteroid. Apparently the only specimen 

known is the single internal cast o:f the left valve, described and figured by Hall. The anterior 

end is incomplete but appears to have been faintly auriculate. The species is apparently a 

Li.moptera s. str. and, if so, is the oldest one known from the American faunas. 

Avicula (Pterinea?) correc._ta Barrande, 5 from the Silurian etage E2 of Bohemia (equivalent of Aymestry and Guelph), hns the general superficial expression of a Limoptera and, if it 

belongs to the genus, is probably the oldest species know.n,,being earlier than the Helderberg 

L. pauciradiata. 

In the Bohemian Lower DeYonian or Hercynian faunas of etage F2 occur several typical 

species of Litnoptera represented by such forms as Avicula (Pterinea?) ala Barrande,6 A. (P.?) 

bohemica Barrn.nde, L. volitans ;Barrande, and several others. Species of Limoptera of this type 

are widespread in the Lower Devonian, occurring in the Harz region in Germany (Pterinea 

he1·cyn'i:£ (Giebel),' frorn the calcareous beds of Schneckenberg, in the I-Iarz Mountains), and in 

the Erbray lin1estone fauna of western France (Limoptera bohemica (Barrande)). 8 

In the Rhenish Devonian Lim.opter~:t s. str. is unknown, its place being taken by Myalinodon.ta 

and Paropsis. In the Arnerican faunas Limoptera s. str. is well developed and widespread in the 

upper Eo-Devonian and in the M:iddle Devonian faunas. In the higher beds of the Onondaga 

("Corniferous") lirnestone at Stafford, Genesee County, N. Y.,, occurs Limoptera pauzJerata 

I-Iall. 0 Pterinea grandis I-Iall,t 0 ·which occurs in the Jeffersonville ("Corniferous") limestone of 

Scott County, Ind., appears to be a Limoptera. In the Lower Devonian lin1estone of the 

Eureka district, Ney., 11 occurs a large, erect, strongly rnarked limopteroid which probably 

belongs to Limoptera s. str. LimozJtera sarmentica Walcott, frorn the Lower Devonian of the 

Eureka district, does not seem to belong to the genus. 

1 Oohlort, D.P., Note sur quelques pclecyopde:; devoniens: Soc. geol, France Bull., 3d ser., vol. 16, p. 647, pl. 15, fig. 1, 1888. 

2 Uall, James, Paleontology or New York, vol. 5, pt. 1, p. 249, pl. 26, fig. 10, pl. 29, figs. 5, 6 (not pl. 92, fig. 10), 1884. 'I' he shells illustrated on 

pl. 27, fig. 4, and pl. 29, fig. 2 (?),and labeled Limo]Jtera macroptera may also possibly belong to the species Limoptera (Paropsis) obsoleta. 

s F1·och, Fritz, op. cit., pp. fH, 66. 

• Hall, James, Paleontology or New York, vol. 3, p. 28i, pl. 52, fig. 8, 1859. 

G Barro.nde, Joachim, Syst~mo silurien du centre de la Boh~me, vol. 6, pl. 20.5, box III; pl. 217, box V; pl. 218, figs. 21-23; pl. 281, figs. 1-6, 1881. 

o Idem, p1.223, box IV. 

7 Kayser, l~manuol, Die Fauna der iiltesten Dovon-Ablagerungen des Ha.rzes: Abh.geoi.Specialkarte Preussen, vol. 2,pt. 4, p.133, pl.l9, fig.1, 

1878. 

s Bo.rrols, Charles, Faune du calcaire d'Erbray: Soc. geol. Nord Mem., vol. 3, p. 173, pl. 10, fig. 9, April, 1889. 

o Hall, James, Paleontology of Now York, vol. 5, pt. 1, p. 243, pl. 26, fig. 5, 1884. 

10 Idem, p. 91, pl. 83, fig. 14. 

II Walcott, C. D., Paleontology or tho Eureka district [Nevada]: U.S. Geol. Survey Mon. 8, p. 168, 1884. 
204 FAUNA OF THE CHAPMAN SANDSTONE OF MAINE. 

In the Middle Devonian (Hamilton) of America Limoptera s. str. reaches its maximum 

development. Several species occur in the Hamilton faunas of New York 1 and Indiana. 2 

The genus is not reported fron1 any faunas more recent than the Hamilton. Its range is 

therefore from the middle part of the Silurian to the Middle Devonian and it is most widespread in the upper Eo-Devonian arid the Meso-Devonian. 

LuroPTERA PAUCIRADIATA Hall var. CHAPMAN! var. nov. 

Plate XXIII, figures 4, 10. 

Hall's original species is described. from a single internal cast of the left valve in the New 

Scotland ("Delthyris") lin1estone of New York. An imperfect internal mold in the C)lapman 

faunas agrees superficially with Hall's specimen as figured, but the corresponding external n1old 

fron1 Maine shows some interesting features of ornamentation not indicated on the interior. 

Whether such external features will be found on the New York L. pa1.wiradiata, should that 

species ever be discovered, is of course problen1atic. The Chapn1an fossil may therefore be 

identical with L. pauciradiata (Hall) or it may be quite distinct. I have chosen for the present 

to describe the specimens as the variety chapmani, in the belief that this "variety" will ultimately prove to be either a synonym or a distinct species. 

Outline vertically elongated, nearly erect, slightly oblique; obliquity 15° or 20° from the 

perpendicular. Height (about 39 millimeters) equal to or a little greater than one and one-half 

times the length (about 26 millimeters). Posterior wing very large, the height of the wing 

equal to its length; wing distinctly demarcated from the body. The posterior margin of the 

wing is concave; for the greater portion of the height the margin extends upward and only 

·Very slightly forward in a nearly straight line, and then for a shorter distance curves backward 

a little more strongly to the hinge. The anterior portion of the shell including the ear is unknown. 

The body of the shell is narrow and high. The umbo?al angle is acute, hardly, if' at all, exceeding 

about 45°. The beaks are depressed to the hinge line and do not extend above it; they are 

situated very far forward on the hinge or are subterminal. The s·pecinlen is broken, so that it 

can not be ascertained whether or not the beaks are quite terminal, though they appear not to 

be. The oblique height or axis of the body is equal to about twice the ob]ique width or length 

of. the body. The anterior margin is apparently nearly vertical and is slightly rounded. The 

ventral margin is deeply convex. Most of the posterior niargin of the shell is included in the 

wing. The hinge extremity is approximately directly over the posterior extremity of the body. 

The left valve described and figured is somewhat crushed from front to back, but even so it is 

only: of moderate convexity and not ventricose. The wing is concave .. The front slope of 

the body to the anterior margin is abrupt. The point of maxi1num convexity is on the middle 

of the body. Ligamenta! features, dentition, and muscular scars unknown. 

The internal mold is marked on the middle and hinder portion of the body by coarse low 

radial ribs, the nu1nber of which is indistinct but is apparently eight or nine, as in L. pauciplicata; 

certainly not greater than ten or twelve. Near the ventral n1argins the ribs becon1e obsolescent, 

and this portion of the shell is marked dominantly by concentric strire of growth. · Con1pare 

similar senile obsolescence of radial ornan1entation in Limoptera ala (Barrande) ;

3 Limoptera 

macroptera (Conrad)/ Ectenodesma birostratum Hall, 5 and Tiogan·a chemungensis (Conrad). 6 

Such more or less abrupt senile obsolescence of radial ornan1entation, usually accompanied by 

' increasing don1inance of the concen.tric ·strire, is a very common feature in radially ribbed 

pterinoid and aviculoid shells. The anterior portion of the body is without any distinct radial 

ornamentation.· The wing on the internal mold is also without radial ornamentation and is 

marked by concentric lamellose strire of growth, which occasionally becomes varicose. Con1 Hall, James, Paleontology of New York, vol. 5, pt. 1, pp. 243 et seq., 1884. 

2 Idem, p. 244, pl. 26, figs. 1-4; pl. 92, figs. 1-3. See also Kindle, E. M., The Devonian fossils and stratigraphy of Indiana: Indiana Dept. 

Geology· and Nat. Res. Twenty-fifth Ann. Rept., p. 664, pl. 13, fig. 6, 1900. Kindle mentions its occurrence in the Jeffersonville(" Corniferous") 

limestone, as well as in the Sellersburg limestone, of Hamilton age. 

a Barrande, Joachim, op. cit., pl. 218, figs. 21, 22. 

• Hall, James, Paleontology of New York, vol. 5, pt. 1, pl. 92, fig. 9. 

"Idem, pl. 84, fig. 20. 

6 Idem, pl. 16, fig. 10. 
MOLLUSCA. 205 

centric strire also cross the body, hut at greater intervals. On the external n1ol.d the wing is 

ornamented with fine radial lines, eight or nine in the space of 5 millimeters. These radial 

lines are sepa~·ated by interspaces two or three times their width; they are crossed by concentric elevated la1nellose lines which arch forward in the interspaces. These concentric 

lamellose lines are closely set and continuous, t6 having been counted in the space of 5 

millimeters. They also cross the body of the shell, especially in the hinder portion, where 

they are visible in the interspaces. between· the ribs and on the forward portion of the body. 

On the external n1old the radial ribs on the body are seen to be very much narrower than their 

broad interspaces; on the forward part of the body the ribs appear to be obsolescent, concentric 

strire being 1nore d01ninant. Ten or twelve principal ribs may be counted on the body, and in 

a couple of interspaces ~n the hinder part of the body a finer rib is intercalated. The concentric 

strire crossing the ribs are in1bricos.e. 

Locality: Chap1nan sandstone, Edmunds Hill, Chapman Township, Aroostook County, 

Maine. 

U.S. National Museum, catalogue No. 59802. 

Oom1Jarisons.-The shell agrees with the Helderbergian Limo1Jtera pauciradiata (Hall) in 

having the height greater than the length; in the very slight obliquity (only 15° or 20° fron1 

the perpendicular); the radial ribs on the body few in number (less than 10); the wing large, 

as high as long, and, on the interns,} mold or cast, without radial ribs but with strong concentric 

n1arkings, etc. 

Apparently the smne species is represented by the shell termed "Pterinea intercostata" 

Clarke, fro1n the Eo-Devonic fauna of Dalhousie, New Brunswick. In the Dalhousie shell the 

wing is not quite so high as in the Chap1nan and New Scotland forms of L. 1Jauciradiata. The 

C.hapn1an shell has the .high wing of the New York type, but is SinaHer, 1nore nearly of the 

size of the Dalhousie fossil. All three, if they do not actually represent a single species, n1ay 

be closely associated in a characteristic group of limopteroid shells. 

Gonus PREA VICULA gen. nov. 

So)_ne shells, the external·charn.cters of which are very close to those of Megambonia oblonga 

I-Iall, are here separated from the genus Megambonia Hall and placed in a- new generic group, 

Preavicula. The type species I h~:Lve supposed to be identical with Hall's species },fegambonia 

oblonga, but the material on which the genus is founded is fron1 the Chapman sandstone. In 

case I-Iall's incompletely understood species on further investigation proves to represent a different shell the specific name Prea'lricula oblonga will remain as the d~signation of the Chap1nan 

species. 

The shells are heteromyarian or monomyarian shells, having the anterior muscular scar 

deep and distinct, though 1ninute, and situated in the rostral (umbonal) cavity rather than on 

the ear; the posterior scar large, well defined, situated below and back of the middle, and 

distant about its own width from 1jhe posterior margin. The outline is characteristic, differing 

fr01n that of normal Aviculidre in that both the anterior and posterior margins ai·e convex 

throughout, the latter retrorse and obtusely curving into the very short hinge line, so that 

the outline corresponds more neady with that of the Cyrtodontidre. There is, therefore, in 

these shells no true aviculoid alate wing, nor is there any true aviculoid or pterinoid auricle. 

An anterior end in front of the u1nbones is well developed, but it n1erges into the gibbous body 

and is not separable fron1 the body by any byssal sinus or marginal insinuation of outline, nor 

does either the anterior or the posterior margin becon1e concave just below the hinge line. 

This last-mentioned feature serves to distinguish the shells from Rutotia and indicates that 

the shells, though of large size, represent a condition in outline, equivalve convexity, and mus~ 

culature present in the e1nbryonie for1ns in the more recent Avicula. The fossils in outline, 

in convexity, and in ligament n1itght easily be mistaken for members of the CypricarditesCyrtodonta group, but the n1uscular scars prove their heteromyarian character. The generic 

diagnosis is as follows: 
206 FAUNA OF THE CHAPMAN SANDSTONE OF MAINE. 

Equivalyed, inequilateral, oblique; the u1nbones full, directed anteriorly, and in the typical 

forms situated more than one-third the length of the hinge line from the front. Anterior end 

large, rounded, not separated from the body py any byssal sinus or marginal insinuation of the 

outline; anterior margin convex throughout and rounding into the hinge line. The body of 

the shell is inflated below the umbones, and oblique (when orien~ed with the hinge line, horizontal). Posterior margin retrorse, convex throughout, rounding into the binge line. Hinge line 

short; in typical specimens continuously straight in front of and behind the beaks. The portion behind the beaks is slightly longer than the anterior portion. Both valves are highly 

inflated and apparently equivalve, but the two have not been observed in conjunction. Two 

isolated left valves viewed in profile from the anterior end show appearances of a slight gape 

of 1 to 1.5 centimeters below the hinge, but whether an actual gape really existed 'can not be 

determined. 

On the interior the forward n1uscular scar is distinct, though 1ninute, and is deeply in1pressed 

about the apex of the umbonal cavity, rather than on the anterior end of the shell. The 

posterior scar is 4 or 5 1nillimeters broad, is situated back of and slightly below the middle, 

and is separated by about its own width from the posterior n1argin. Pallial line strongly 

developed on clean internal molds; simple. Two very low, faint ridges diverge fron1 the 

umbo on the interior of the valves and terminate, respectively, at the front and at the back 

of the posterior muscular scar. Ligament external; observed on only a single specimen, where 

it was striated and about a millimeter in width. The hinge is apparently edentulous. The 

shell is of moderate thickness, pearly on the interior, surface smooth or with tenuistriate lines 

of growth. The Chapman ~hells here identified ·with Megambonia oblonga Hall are selected 

as the type of the genus. 

In the convex posterior margin and absence of the real aviculoid or pterinoid wing the 

genus Preav:icula represents a prin1itive or embryonic type of Avicula con1parable with a few 

Ambonychidre and with the genus Rhombopteria Jn.ckson. .Fron1 the An1bonychidre Preavicula _ 

may be distinguished by its distinct, rather large anterior end and by the presence of a distinct · 

anterior 1nuscular scar. From Rhon1bopteria Jackson Preavicula differs i1Y ornan1entation; 

in Rhombopteria the anterior end has the character of the usual aviculoid or pterinoid auricle, 

whereas in Preavicula the anterior margin is convex throughout without a n1arginal sinus to 

form an "auricle.'; Rhombopteria is described as having teeth, the posterior laterals elongated. Preavicula apparently lacks posterior lateral teeth, and no cardinal teeth have been 

discovered in it. Finally, Rhombopteria is pronouncedly inequivalve. Rhombopteria was 

noted by Jackson as being one of the most primitive aviculoids known. Preavicula appears 

to be an even more primitive type, for not only is the norn1al aviculoicl posterior wing absent, . 

but the aviculoid "auricle" as such is also absent, the shell having nllwh the outline and external appearance of the di1nyarian Cypricardites-Cyrtodonta group. Posidonmnya conforn1s 

with Preavicula in having no true auricle; and in Posidonomya beche1'i Brown the posterior 

. margin is often convex or nonalate throughout. The Posidonon1yidre are, however, thinner 

a.nd 1nuch more compressed shells and have narrower ligan1ents. Typically also in Posidonon1ya 

the posterior margin is concave for a short distance just below the hinge line. 

Tlie affinities of Preavicula appear to be with the nonauriculate, nonalate, edentulous, 

concentrically n1arked Posidonomya Brown, ~Aucella Keyserling, and Rutotia De Koninck. 

Besides the type species, the genus Preavicula probably includes Rutotia elliptica Whidborne,t from the Eifelian or Meso-Devonian and from the Cuboides zone or lower N eo-Devonian of Lummaton and W oolborough, England; },fodiola? annulosa De IConinck, 2 from the 

Carboniferous of Vise, Belgium; and probably Pterinea? mytiloides Clarke, 3 fron1 Dalhousie, 

New Brunswick, in Eo-Devonian rocks. The last-named species may not be specifically distinct 

frmn the type species. 

1 Whidborne, G. F., A monograph of the Devonian fauna of the south of England, pt. I, vol. 2~ p. 55, pl. 5, figs. 2-9 (not pl. 4, figs. 9-10, which 

show a mytiloid), London Paleontogr. Soc., 1892. · 

2 De Koninck, L. G.; Faune du calcaire carbonifere de la Belgique, pt. 5, Lamellibranches, p. 180, pl. 29, fig. 18, 1885. 

a Clarke, J. M., Some new Devonic fossils: New York State Mus. Bull.107, p. 208, fig., 1907. 

' 
MOLLUSCA. 

PREA VICULA OBLONGA (Hall). 

Plate XXV, figures 21, 22, 25, 26; Plate XXVI, figures 11, 15, 16. 

(?) 1859 . .Megantbonia oblonga. Hall, Paleontology of New York, vol. 3, p. 277, pl. 50, fig. 5. 

Helderberg shaly limestone: Schoharie County, N.Y. 

(?) 1907. Plerinea? mytiloides. Clarke, New York State Mus. Bull. 107, p. 208, fig. 

Lower Devon.ic: Dalhousie, New Brunswick. 

207 

The Chapman sandstone specimens here identified with Hall's species display the following 

characters: 

Shell rn.ther large, inequilateral, obliquely narrow ovoid, with the body obliquely inclined 

at an angle of 45' 0 , more or less, frorn the short hinge line. Umbone subcentral, situated at about 

the anterior two-fifths the length of the hinge, directed forward and protruding somewhat above 

the hinge line. Anterior to the be~ks the hinge line is straight, continuous with the portion 

posterior to the beaks and rounding forward into the anterior n1argiu. The anterior margin is 

convexly rounded throughout; for the uppermost centimeter it is connnonly vertical and perpe.ndiculm· to the hinge line, though occasionally it is vertical for only a few 1nillin1eters. Below· 

this verticnl portion the anterior n1argin swings backward and downward in a broad, shallow 

cun7c, swinging abruptly into the retrorse posterior margin without the intervention of any . 

de:finable ventrnltnm·gin. · The anterior extreniity of the shell is 2 to 10 1nillimeters below the 

hinge line; the lowest point of the Jnargin is far back, either clirectly below or, lnore commonly, 

posterior to the hinder hinge extrenaity. The posterior n1argin is retrorse and convex throughout, with the hindmost extren1ity near the postveutral angle, approximately 1nidway in height 

between the ventral 1nargin and the base of the posterior n1uscular scar. The lower tbreefotu·ths of the anterior margin forn1s with the posterior 1nargin an oblique SJlnmetrical elongate 

smniellipse. The hinge extrmnity is obtusely rounded. The hinge margin and the portion of the 

shell in1n1ediately below were apparently thin; they are rarely preserved.. The hinge line appears 

to h.n.vo been short and straight or nearly strnight. Both valves are ventricose, especially over 

tho n1idclle of the body and in the umbones. The tnnbones project smnewhat above the hinge 

line. There is no fiattened posterior aviculoid \ving,. the postun1bonal slope being convex and 

very steep. For 1 or 2 milluneters bdow the hinge line the postu1nbonal slope becomes less steep, 

but this portion of the shell is broken off in the great 1najority of specimens. Just back of the 

bcn.ks tho posterior slope is very steep, nearly vertical. The slope to the anterior nlargin is also 

stoop. Occasionally a portion of the anterior end of the shell which includes the supposed gape 

appcn.:rs to be faintly inflated like a.n aviculoid ''auricle." The anterior portion in1n1ediately 

in front of the beaks wn.s depressed convex but is usually broken off in the specimens. The point 

of mn.xinnnn depth is over the center of the shell. The depth of each valve is equal to a quarter 

of the length fron1 beak to postventral extremity. 

A pro:file ex~:nuination from the a,nterior end of four or five internal molds of isolated valves, 

both right and left, shows a gape 1 or 2 millin1eters deep in each valve. This gaping portion of· 

the shell extends along the anterior 1nargin for about 1.75 centinieters belo''-' the hinge line. 

The appen.rance suggesting this slight. gape has been observed only on isolated valves in internal 

molds ~vhen viewed in profile fron1 the anterior end. I have see,n no specimens with both valves 

in conjunction; and the appearances, if not deceptive, 1nay possibly be only accidental. Orr one 

of the specilnens fron1 Edmunds I-Iill the hinge line is preserved with a striated ligamenta! area 

a little OYer 1 1nilli1neter in width. This area is inclined at a low angle to the plane of the n1argin. 

Dentition not obserYed. Several clean internal molds indicate probable absence of posterior 

la.tcrul teeth. The anterior scar is a. pit about 1n1illin1eter in width in ·large shells, deeply sunken 

into the forward part of the un1bonal eavity, near the n1m·gin between the .cavity and the anterior 

portion of the shell. The position of the anterior scar is in the umbonal cavity rather than on 

tho anterior end or auricle. The posterior scar is situated entirely back of and below the middle 

of tho shdl. It is 4 to 6 1nillin1eters in width in mature and large shells, and it is separated 

by its own width from the posterior :margin and also from the middle of the shell. The posterim· scar is strotigly impressed, though less so than the anterior scar. The dorsal and 
1 208 FAUNA -OF THE CHAPMAN SANDSTONE OF MAINE. 

anterior margins and to some extent the ventral margms of the posterior scar are w:ell defined 

and impressed into the shell; the hind margin of the posterior scar is not definable. · 

Clean internal molds of the interior of both valves show a low, rounded, faint radial fold 

extending from the forward extremity of the posterior muscular scar toward the umbones and 

similar fold extending from the postdorsal corner of the scar toward the umbones. Pallial line 

simple, rather deeply impressed into the shell. The pallial line reaches the postventral portion 

of the posterior scar, so that most of the scar is included within the pallial line. 

The surface ornamentation· is variable. A few specimens appear smooth or with faint 

concentric undulations, but most of them are concentrically striate, and fascicles of growth may 

be elevated into low incomplete undulations, or into severallamellose varicles.of gro~th. The 

striffi appear to be most strongly impressed on the forward part of the body and especially on 

the pseudo auricle. · 

A nearly mature specimen has a length of 33 millimeters from beak to postventral extremity. 

In large and mature specimens-this distance is from 49 to 54 millimeters .. 

Locality.-Chapman sandstone, 2 miles west of Presque Isle Stream (locality 1099 J); several 

small specimens fron1 locality (1099 K) 2! miles west of Presque Isle Stream; Chapman Township, Aroostook County, Maine. Some large imperfect casts found loose on Edmunds I-Iill 

(localities 1099 C, C') seem to belong to the species; one of them which is figured shows the 

ligament. 

U.S. National Museum, catalogue Nos. 59803, 59804, 59805. 

Oomparisons.-The specimens as ordinarily preserved present the external aspect of the 

New Scotland Megambonia oblonga Hall, agreeing in every essential particular except in lacking 

the broad, shallow sinus which Hall described as occurring in the ventral margin of the New 

York shell. However, it may be that this described insinuation in Megambonia oblonga is not 

real. The lines of growth represented in Hall's figure show that the anterior margin in the New 

York types was, as in the Maine shells, convex throughout, and that the apparent insinuation is 

due to incompleteness of the specimens. . 

Pterinea? mytiloides Clarke/ from Dalhousie, New Brunswick, also appears to represent a 

Closely similar if not the same specific .type. The Dalhousie fossil was figured as having a 

modiomorphoid ventral insinuation. It is smaller thap. the Maine specimens and, as figured, has 

a longer posterior hinge line and is more oblique. Preavicula elliptica (Whidborne) is easily 

distinguished from the Chapman forms in outline, and especially in having the anterior and 

posterior portions of the hinge line discontinuous. In Preavicula annulosa (De Koninck) the 

body is much broader than in the Chapman shells. 

PREAVIOULA BREVIS sp. nov. 

Plate XXVI, figures 8, .9. 

Two specimens associated in the same rock with Preavicula oblonga differ from that species, 

being much less extended along the line of the umbonal slope, so that the outline is bron,dly 

oval, with the length scarcely greater than the width. In the umbonal portion, the cardinal 

slope, and the general form of the upper portion of the shell P. brevis is very similar to the more 

common species. Comparison is made difficult by the fact that only t'\VO specimens, both left 

valves, of P. brevis are available .. Possibly they represent a short variety of the more oommon 

shell, but until more _specimens are obtained the separate name n1ay stand. 

Locality: Chapman sandstone, in· a calcareous sandstone 2 miles west of Presque Isle 

Stream, Chapman Township, Aroostook County, Maine. 

U. S. National Museum, catalogue No. 59806. 

Genus LEIOPTERIA Hall. 

The genus Leiopteria was founded by Hall to include some concentrically striated, oblique 

aviculoid shells, such as Leiopteria dekayi and L. rafinesqui Hall an9, nearly a dozen other species 

from the Hamilton; Avicula lcevis Hall, from the Marcellus; Avicula chemungen.sis Vanuxem 

1 Clarke, J. M:., New York State M:us. Bull. 107, p, 208, fig., 1907. 
MOLLUSCA. 209 

and L. linguiformis Hall, from tht3 Portage (Ithaca shale member) and the Chemung; and L. 

to'rteyi, from the higher sandstones and conglomerates of the Chemung formation near Panama, 

N.Y. In the left valves the shells nre superficially indistinguishable fro.m Pterinea lrevis Goldfuss, 

the genotype of Pterinea, conforining with Pterinea s. str. 1 in the obliquity, convexity, snutll 

rounded ear, well-developed byssall sinus, long oblique body, well-developed wing, with deeply 

sigmoidal posterior margin, and concentric ornamentation. Leiopteria is distinguished from 

Pteri.nea, however, in having the right valve always convex and frequently almost or quite 

equal in size to the left valve; the ligamental area is narrower than in Pterinea, a,nd the lateral 

teeth, if present, are close under the hinge line, not oblique.. Leiopteria is also Closely allied 

to the genus Pteronitella Billings, agreeing with it in having the right valve convex and frequently nearly or quite equal to the left valve, a·nd in having the posterior lateral teeth close 

under the hinge line. The shells of both gei1era are also concentrically ornamented. Leiopteria 

differs from Pteronitella in being always more oblique, not erect, and in having the byssal sinus 

generally better developed. Anatomically Leiopteria differs from Pterinea, Pteronitella, and 

the pterinoids in lacking the definable anterior muscle on the ear; the pallial line ends in the 

mnbonal apex. Leptodesma Hall is distinguishable from Leiopterla by its greater obliquity, 

sn1aller size, and generally less definite byssal sinus; moreover, as suggested by Hall, the anterior 

. end is rounded and am·iculate in Leiopteria and usually pointed and nasute in Leptodesma. 

A full generic diagnosis of Leiopteria Hall is as follows: 

Shell obliquely aviculoid; biconvex; right valve convex, equal to the .left in many specimens, 

but generally a little less convex; never resupinate. Auricle distinctly developed, rounded, 

usually not pointed; separated frOin the body by a well-developed byssal sinus. Body of the 

shell elongated ovoid; oblique, generally about 30° from the vertical, rarely if ever 45° or more; 

deeply rounded below: The umb()Jles are near the a1.1terior end ·but never terminal and are 

directed forward. The posterior wing is distinctly developed, flat to concave, and with a concave posterior margin. The body of the. left valve is of moderate convexi~y; the wing is flat to 

concave; the auricle is convexly rounded; and the byssal sinus is typically represented on the 

surfape as well as in the margin. Ligament external, extending the length of the hinge line; 

usually very thin or linear and n11trked by only a single striation (Leiopteria lrevis, conradi,. 

gteeni, rafinesq_ui, sayi, bigsbyi, mitchelli, and gabbi Hall); occasionally slightly broader and with 

two or three striations (L. delcayi and linguiformis Hal~), rarely with several strire (L. ·riesiana). 

No cardinal teeth yet reported or observed. Posterior lateral teeth not generally observable, 

but in a few shell~ apparent traces of a ridge or posterior lateral tooth have been recorded by 

I-Iall close under the ligament. Posterior muscular scar large, broadly oval to subci.rcular, 

situated mainly or entirely upon the body of the shell (L. linguiformis Hall). The anterior 

scar hn.s been observed only in the Chapman specie~ L. riesiana, where it is minute and not very 

well iinpl·essed and is situated in the forward part of the rostral cavity (compare Glyptodesma, 

Leptodesma, Limoptera) and not upon' the auricle, as in Pterinea, Cornellites, Follmannella, 

Actinopterella, and Pteronitella. In Hall's description of L. delcayi Hall, the ge.notype of 

Leiopteria, he mentions a low, septum-like 1:idge between the auricle and rostral cavity. This 

may possibly be the posterior boundary of a small anterior ·muscular scar; if so, it would seem 

to indicate that the scar is really situated on the auricle. Pallial line simple. Shell thin. 

The sm·face ornamentation consists of concentric strire, strongest on the posterior half of 

the body and. on the wing. No rndial ornamentation except, very rarely, a few faint radial 

lines on the body of the right valve. 

More than a dozen species of Leioptera, ranging from the lowest }.1eso-Devonian (Marcellus) 

to the highest N eo-Devonian (higher sandstone and conglomerates of the Chemung near Panama, 

N. Y.), were described by Hall. 2 The genus seems to attain its maximum development in 

species, individuals, and varieties in the Hamiltoi1 formation throughout the calcareous facies 

of western New York, the shaly fa~~ies of central New York, and particularly the arenaceous 

1 Williams, H. S., On tho revision of the mollusk genus Pterinea Goldfuss: U.S. Nat. Mus. Proc., vol. 34, pp. 83-90, 1908. 

2 Hall, Jamos, Paleontology of Now York, ...-ol. 5, pt. 1, 1884. 

50245°-No. 89-16--14 
210 FA UN A OF THE CHAPMAN SANDSTONE OF MAINE. 

facies of eastern New York. It is common also in the Hamilton type of fauna, which continues 

into the Ithaca shale member of the Portage formation in eastern New York. It is rare at 

Ithaca and ·in the Cheml.}.ng. The genus passes down below the Marcellus into the Oriskany, 

where it is represented by Megambonia (Leiopteria) lamellosa Hall/ from the Orl.skany sandstone 

of Oriskany Falls, Oneida County, and the Helderberg Mountains in Albany and Schoharie 

counties, N. Y., a very·large form of Leiopteria aspect. Hall neither :figured nor described the 

right valve, the hinge, nor the internal structure, but the fact that he included the species in 

Megambonia, which is equivalve or nearly so, indicates that the right valve, if it has been seen, 

is convex as in Leiopteria. The genus occurs also in the lower and middle parts of the Helderberg group and as low as the Rochester shale member of the Clinton formation of the Niagara 

group. It is apparently unknown in the Ordovician. 

Above the highest Devonian Leiopteria occurs, as reported by Herrick and by Miller and 

Gurley, in the Mississippian·(" sub-Carboniferous") faunas of the Mississippi Valley, but these 

post-Devonian so-called species of Leiopteria 2 are small, very oblique shells, with broad, undefined byssal sinus, and ought for the most part to be included.- in Leptodesma Hall. Avicula 

subspatula Herrick 3 however, from the Mississippian of Newark, Ohio, seems to be a typical 

Leiopteria in outline and convexity.- In Europe Leiopteria is reported from the Carbonif~rous 

by De Koninck, 4 who records 21 species from etages II .and III of Belgium and equivalent 

British rocks. Of these L. phillipsi (De Koninck)/ L. Zunulata (Phillips),6 and L. maccoyi 

(De Koninck) ,7 approach Leiopteri.~ only remotely; the other species described by De Koninck 

are, as in the American Carboniferous, typical L~ptodesma-very oblique shells of small size, 

with broad, undefined byssal sinus. Hind also confused the genus Leptodesma with Leiopteria. Leiopteria grandis Hind,8 fron1 the Carboniferous limestones of Yorkshire and Derbyshire, England, seems to be the only really typical described form of Leiopteria in the British 

Carboniferous; the remaining seven species described and :figured by Hind are either the usual 

small, very oblique, ·~ypical Leptodesma (L. thompsoni, L. hirundo, L. longirostris) or intermediate Leiopteria-Leptodesma shells (L. lunulata pars, L. laminosa pars), except Leiopteria 

obtusa (McCoy), which appears to be _a small Ptychopteria. The genus Leiopteria therefore 

probably extends up into the Carboniferous, though it is very rare above the Devonian. 

As to the Devonian and Silurian distribution outside of New York, the genus Leiopteria 

has been·recorded byWalcott 9 from the Lower Devonian of the Eureka district, Nev., and by 

Clarke 10 (L. hawkinsi Clarke) from tP.e Lower Devonian of the Rio Curua, Para, Brazil. 

In the English Devonian the genus appears to be unrecognized. The so-called Leiopteria 

Zingulata Whidborne 11 is a pectenoid shell of the· genus Crenipecten, or poss~bly Streblopteria 

or some allied forn1. Leiopteria is, however, well developed in the French Devonian, where 

it is represented by Avicula gervillei Oehlert,12 Avicula pseudolcevis (Oehlert) s. str./3 Avicula 

pulchella Oehlert, 14 Pterinea kerfornei Oehlert, 15 Leiopteria picta Oehlert, 16 Leiopteria. viennayi 

Oehlert, 17 _and Leiopteria leucosia Oehlert. 18 

1 Hall, James, Paleontology of New York, vol. 3, p. 467, pl. 109, figs. 5, 6, 1859. 

2 See Weller, Stuart, A bibliographic index of North American Carboniferous invertebrates: U. S. Geol. Survey Bull. 153, p. 318, 1898. 

3 Herrick, C. L., The geology of Licking County, Ohio, pt. 4: Denison Univ. Sci. Lab. Bull., vol. 4, p. 30, pl. 5, fig. 11, 1888. 

4 De Koninck, L. G., Faune du calcaire carbonifere de la Belgique; Lamellibranches: Mus. royal hist. nat. Belgique Annales, vol. 11, pp. 187 · 

et seq., pl. 30, 1885. 

5 Idem, pl. 30, fig. 8. 

a Idem, pl. 30, fig. 4. 

1 Idem, pl. 30, fig. 3~ . 

8 Hind, Wheelton, A monogrf!,ph of the British Carboniferous Lamellibranchiata, vol. 2, pt. 1 (London Paleontogr. Soc. Pub., vol. 55), p. 19, 

pl. 3, figs. 12-15; December, 1901. 

9 Walcott, C. D., Paleontology of the Eureka district [Nevada]: U. S. Geol. Survey Mon. 8, p. 166, pl. 5, fig. 10, 1884. 

10 Clarke, J. M., The Paleozoic faunas of Para, Brazil, pt. 2, Devonian Mollusca: Mus. nac. Rio de Janeiro Arch., vol. 10, p. 49, ·fig.,1899 (author's 

English ed., 1900). 

n Whidborne; G. F., A monograph of the Devonian fauna of the south of England, vol. 2, pt. 2, p. 78, pl. 10, fig. 1, 1892. 

12 Oehlert, D."P., Documents pour servir a !'etude des faunes devoniennes dans !'ouest de la France: Soc. geol. France Mem., ·ad ser., vol. 2, 

r. 22, pl. 3, fig. 4, 1881. Lower Devonian, Nehou, La Manche. 

13 Idem, p. 23, pl. 3, fig. 5. Nehou. 

u Idem, p. 24, pl. 3, fig. 6. Nehou. . 

Ia Oehlert, D. P., Note sur quelques pelecypodes devoniens: Soc. geol. France Bull., 3d ser., vol. 16, p. 642, pl. 14, fig. 1, 1888. 

1a Idem, p. 643, pl. 14, fig. 3. 

11 Idem, p. 643, pl. 15, fig. 3. 

18 Idem, p. 644, pl. 14, fig. 2. 
MOLLUSCA. 211 

In the German Devonian several species of Leioptera, probably distinct, are called by 

Frech. 1 Avicula crenatolarnellosct Sand berger var. pseudolr.evis Oehlert. Avicula schrenki Frech 2 

is also a Leiopteria. All are from the Eo-Devonian. Avicula (Leiopteria) winteri Frech 3 

is fron1 the lower Meso-Devonian (Calceola beds). Frech calls Leiopteria the "group of 

Aviculct winte,ri," considering JEiall's genus a synonyn1 of A vicula. A vicula (Leiopteria) sp. 

Frech, 4 fron1 the Belgian Gedinnian, appears to be a poorly preserved Actmopteria or Actinopterella; it shows traces of radiate ornamentation on the body. 

I~1 the Bohemian basin the genus Leiopteria is fairly well developed in both the Silurian 

and the Eo-Devonian. To it are referable Avicula opportuna Barrande,& which appears to be 

a large typical member of the genus; A. carens Barrande, 6 A. irnpotens Barrande/ and A. 

sm'Viens Barrande,8 all from the Silurian etage E 2 (Aymestry or Ludlow equivalent); and Aviculct imperfecta Barrande,0 A. 1:nvisa Barrande/0 and ·A. gratior Barrande,11 from the Eo-Devonian or flercynian etage F2• 

LEIOPTERIA RIESI~NA sp. nov. 

Plate XIX, figure 21. 

This species is characterized by its equivalve, depressed convexity, slight obliquity, and 

very sn1all ear; by the posterior margin of the wing being not at all or only slightly concave, 

and with an obtusely angled posterior hinge extremity; .and by the absence of lamellm of growth. 

Shells vertically elongate, aviculoid, with height· (perpendicular to the hinge line) generally a sixth greater than the horizontal length, rarely as much as a fourth. Beaks compressed, 

not protruding above the hinge line, prosogy:rate, situated very near the aJ1terior end, fron1 

·which they are separated by a minute auricle. The hinge line is decidedly less than the length 

of the shell, the portion berrind the beaks equaling half to 'three-fifths the horizontal length 

of the body. The posterior hinge extremity is angular, the upper posterior margin directly 

undm; the hinge being p·arallel with the oblique axis of the shell. The posterior margin is hardly 

or not at all sigmoidal, the upper part straight or slightly convex, rarely slightly concave. The 

greater portion of the posterior 1nargin is distinctly convex, with the hindmost extren1ity at 

the inferior third or two-fifths the height above the base. Ventral n1argin deeply bellied down, 

with the inferior extremity 1boward the rear, generally at the posterior third or fourth, rarely 

just back of the n1iddle. The ventral margin rises in a broad sweep into the convex anterior 

n1argin. The anterior margin continues convex for two-thirds to three-fourths the height; 

then develops a fairly long hut shallow byssal sinus in the n1argin, and is again c~mvex over 

the stuall rounded auricle. The anterior margin, for the upper third of the height of the shell, is 

i~1cli.ned to the hinge line at a right angle or at a slightly obtuse angle. The forward extremity 

of the shell is on the body a.bove the n1idheight. The obliquity from the perpendicular varies 

frmn 18° to 23° but is generally nearer the latter. Shell equivalve; depressed convex. The 

body strongly depressed ove:r the greater portion, slightly more convex over the umbones. The 

byssal sinus is shallow and hardly discernible on the surface. The wing is concave, nearly flat, 

and fairly well1narked off fron1 the body. The thickness, with both valves in conjunction, varies 

between two-sevenths and two-fifths the length ("width"). Ligament and dentition unknown. 

The anterior end of the pallial line ends in the rostral cavity, not on the auricle. The anterior 

muscular scar is .minute and not very deeply excavated. The posterior scar is much larger, 

subcircular in outline, 1 centimeter 41 diameter, and is situateq entirely upon the body of the 

1 Frech, ]?rJtz, Dio devonischen Avic'llliden Deutschlands: Abh. geol. Specialkarte Preusseli, vol. 9, pt. 3, p. 51, pl. 4, figs .. 5,5a (?), 5b, 5c, 

13, 13a, 13b. 

2 Idem, p. 56, pl. 4, figs. 8, Sa. 

·a Idem, p. 47, pl. 4, fig. 11. 

• Jdom, p. 48, pl. 7, fig. 4. 

G Darrnndo, Joachim, Syst~me silurieu du centre de la Boh~me, pt. 1, vol. 6, pl. 223, box III, 1881. 

o ldom, pl. 225, box V. 

1 ldom, pl. 229, box I. 

s Idom, pl. 223, box H. 

o Idom, pl. 222, box I, fig. 12. 

10 Idom, pl. 222, box I, fig. 13. 

u Idom, pl. 217, box III. 
212 FAUNA OF THE CHAPMAN SANDSTONE OF MAINE. 

shell, at the midheight and extending just back of the center. The pallial· line is strongly 

impressed on internal molds and is radially wrinkled in the lower portion. It extends vertically 

downward from the rostral cavity in a. depressed convex arch, sweeps backward in its lower 

portion to a point below the posterior muscular scar, and rises for a short distance upward 

and backward to the scar. The scars and pallial line somewhat resemble those of lJfyalina 

maureriana. 

Internal molds are commonly smooth; a "sculpture cast" shows fine obsolescent concentric strire of growth, with no conspicuous varices. The strire are a little finer and more even 

on the wing. 

The size is indicated by the following dimensions: 

Dimensions of typical specimens of Leiopteria riesiana. 

Height Length Thickness 

(millimeters). (millimeters). (millimeters). 

45 38 

43 36 

42 33.5 11 

35 30 11.5 

Locality: Chapman sandstone, Presque Isle Stream, ·Chapman Township, Aroostook 

County, Maine. · 

U.S. National Museum, catalogue No. 59807. 

Oomparisons.-The species closely resembles Leiopteria hawkinsi Clarke from the EoDevonian Rio Curua fauna of Para, Brazil; but in the Maine species the posterior margin of 

the wing is not at all or only slightly concave, and the angle formed at the posterior hinge 

extremity, like the angle formed by the hinge line with the upper anterior margin, is obtuse, 

not acute. These features, especially the obtuse posterior hinge angle, will also distinguish 

the species from many of the other forms of Leiopteria. · 

Family MYALINID.tE Frech. 

Genus MY ALINA De Koninck. 

In his discussion of the D.evonian A viculas of Germany Frech 1 proposed the name Myalininre as a subfamily under Aviculidre, to include· Myalina De Koninck, Mytilarca Hall, and 

Plethomytilus Hall. The genus Myalina is subdivided, according to . Frech, into three groups, 

as follows: (1) Myalina s. str., "Gruppe der Myalina rhenana Frech" =Plethymytilus Hall; 

(2) "Gruppe der Myalina bilsteinensis (F. Roemer)" =Mytilarca Hall (pars); (3) "Gruppe der 

Myalina lodanensis Frech.'' 

On the other hand, Dall,Z in revising the classification of Pelecypoda, places the genus 

Myalina De Koninck in a family ~1ytilinidre Frech, separate from Mytilarca and Plethomytilus 

Hall, which he places in the family Ambonychidre Miller. Mytilus Linnreus is placed by Dall 

in still another family, Mytilidre Fleming, in a different section (Dysodonta Neumeyer) of the 

Prionodesmacea. These are extremes of classification resulting from different points of view, 

the two authors giving differen~ relative values to the several characters of the genera described. 

To open the question as to which classification is more true to nature (whether the boundaries 

of the genus Myalina are considered to be subordinate to the family Myalinidre, or wide e~wugh 

to include the families Ambonychidre Miller, ~1ytilidre Fleming, and Myalinidre Frech)1 is scarcely 

pertinent to the present treatise. 

1 Frech, Fritz, Die devonischen Aviculiden Deuts.chlands: Abh. geol. Specialkarte Preussen, vol. 9, pt. 3, p. 137, 1891. 

2 Dall, W. H., Pelecypoda, in Zittel, K. A., Text-book of paleontology, revised English ed., vol. 1, pt. 1, pp. 368-369,372,385,1896. 
MOLLUSCA. 213 , , I 

MYALINA 1\:lAURERIANA sp. nov. 

Plate XVIII, figmes 1-6, 8, 11; Plate XIX, figures 22, 26. 

I-Ieight greater than the length, in the proportion of 100:72, or about.11 :8, as shown below. 

Dinwnsi:ons of typical specinwns of Myalina maureriana . 

. Height 

(millimeters). 

Length 

(millimeters). Ratio of height to length. 

------

50 36 100:72 

49 35 100:71 

44 32.5 100:73 

ct22. [) 16.5 100:73 

34. fi 25.5 100:74 

49.1) 35 100:71 

a Young specimen. 

Greatest length a trifle below the midheight. Greatest height near the midlength. Beaks 

rarely quite tenninal; a very narrow and steeply inclined auricular portion usually discernible 

in front. Hinge line str~ight, rigid, always shorter than the length of the shell, the proportion 

varying frmn 2:3 to 10: 11. The posterior hinge extren1ity is pointed. The upper part of the 

posterior n1argin near the hingE: is usually very depressed convex, or ne~rly straight, and n1ak~s 

with the hinge line an angle of 115°. Rarely the upper portion, instead of being straight or 

depressed convex, is slightly concave, producing a faintly.Avicula-alate appearance; ge:nerally, 

however, the posterior n1m·gin continues convex to the hinge. The hindmost extremity of the 

shell is a trifle below the midheight, whence the posterior margin curves into the deeply arched 

ventral and antero-ventral 111argins~ which together include a deep paraboloid semicircle. The 

lowest point of the shell is near or just back of the midlength. The anterior margin for the 

lower three-fifths of the heigh·~ of the shell it situated in advance of the umbones; the n1ost 

forward point of the shell variE:s fr01n slightly below to slightly above the midheight; the anterioi.· nun·gin in the upper two-1ifths recedes toward the beaks, producing a usually concave or 

constricted outline; occasionally the extreme upper anterior n1argin at the beaks is again 

gently convex, producing a faint, narrow, auricle-liko ·expansion. The shells are nearly erect .. 

the obliquity fr01n the vertical being less than 10°-in son1e specin1ens aln1ost imperceptible. 

·The shells are apparently equivalved. The body of the shell is of moderate or depressed con~ 

vexity; the shell is never infla.ted. In the 111ost strongly convex specimens the depth of the 

single valve does not attain one-fifth of the height, and the usual depth of the valve (in the 

internal 1nold) is one-sixth to two-fifteenths of the height. The point of maximun1 convexity 

is on the un1bones, whence the surface slopes very gradually toward the ventral n1argin, very 

steeply to the concav·e portion of the anterior 111argin, and less steeply to the posterior part of 

the shell. A subalate upper posterior portion is roughly separated fron1 the body by its more 

depressed convexity. fJ.'he anterior :margin .along the concave portion of the front outline is 

deflected or curled inward in the better-preserved specimens. Hinge structure edentulous; 

but in one of the speciinens the hinge line appears to be marked along its middle by .a fairly 

long horizontal ridge or tooth in the left valve,· fitting into. a· long, narrow trough or socket in 

the right. This structure Inay, however, be only accidental. T~e other specimens are edentulous. The ligan1ental area is of moderate width (for Myalina) and is inclined to the plane of 

the 1nargin at an angle of less than 45°, varying fro1n 10° to about 40°, generally nearer the. 

former. The regular sharp, parallel strire or corrugations which traverse the length of the 

ligan1ent in typical species of Myalina have been observed in only a single mold. In most 

specimens the liga1nental area is only obscurely striate horizontally, and there are also ob:;ervable faint striations, vertical or slightly oblique in the dir~ction parallel to the front margin of. 

tho ligament. These striation:3 are unknown in tho typical species of Myalina a·nd are probably. 

an initial advance toward the divided ligament of Perna and its allies. Just beneath the liga-
214 FAUNA OF THE CHAPMAN SANDSTONE OF MAINE. 

mental strip is sometimes developed a smooth, flat space, somewhat as in Leiomyalina Frech. 

The anterior muscular scar is minute and very deep and is situated under the umbones close to 

the hinge line. It is impressed on the floor of the valves, about 5 or 6 millimeters (in mature 

shells) from the front edge of the hinge line. The posterior· muscular scar is single. or undivided, subcircular, and about 10 centimeters wide; less strongly impressed than the anterior 

muscular scar, but usually discernjble; its posterior and ventral margins inclose a semicircle; 

the upper and inner semicircumference is irregular. · The posterior scar is situated at the ;rnidheight or slightly below. It is entirely posterior to the center, but is nearer to the center than 

to the posterior margin; from the latter the impression is separated by two-thirds to seveneighths its width. The pallial lirie is simple and well developed. From the small umbonal 

scar it extends downward and slightly forward for about half the height of the shell, then 

sweeps backward in a broad curV-e and reaches, near the posterior scar, a point within two-fifths 

or one-third the height of the shell above the base, ·or on a level with the lower Jnargin of the 

posterior scar; the pallial line then rises slightly and reaches the scar on the lower part of the 

inferior anterior quarter. ·The pallial line is nowhere pitted or pustulose. It is most strongly 

impressed on the portion extending downward and slightly forward from the umbonal scat. 

In mature shells it is 5 millimeters or ;more from the margin. From the posterior and upper 

portion of the large musculaF scar. there extends upward to the low hinge a low faint ridge, 

marked by a shallow groove in the internal mold. . 

The shell is 2 millimeters thick, or a trifle more, over the body. To the naked eye and 

under a hand lens no prismatic structure is apparent, the shell structure appearing plainly 

hi.mellose or flaky, or else crystalline with an oblique cleavage into thin laminre. Meek and 

Hayden1 have shown that the shell structure of the genus Myalina (M. angulata) is prismatic. 

The prisms, however, are exceedingly minute or microscopic, only ·one-seventieth to one threehundred-and-fiftieth of a millimeter in width. To the naked eye and even under a hand lens 

the prismatic structure is not discernible, and the species of Myalina when the shell is well 

preserved present a strongly lamellose or flaky shell structure, similar to that of the prese~t 

speCies. . 

Internal molds are smooth and compl~tely devoid of ornamentation. The exterior was 

marked by very faint tenuous lines of growth or very obscure wrinkles, leaving the surface 

approximately smooth, except for one or two strong lamellose or imbricating varices near the 

lower margin in old shells. Where the upper anterior margin was inflected, the inflected portion is n1arked by numerous closely crowded, imbricating lamellre of growth, the ornamentation on this portion being more pronounced than anywhere else on the shell. 

Mature specimens have a height of about 49 or 50 millimeters and a width or length of 35 

to 36 millimeters. 

The distinguishing features of this fossil are its vertically elongate tall form with very 

deep ventral margin; erect outline nearly vertical or with obliquity less than 10°; anterior nlargin convex for the lower three-fifths of the height and extending downward a1id forward below 

the umbones, concave for only a short distance in the upper .portion; shell narrow, with height 

equal to 1 i times the length, or two or more times the length of the hi~ge line; hinge line and 

upper posterior ma1gin forming an angle of 115°; deeply arched ventral margin; shell apparently equivalved and closed; convexity moderate, or more typically depressed; posterior muscular scar subcircular, undiviqed, and situated near the midheight; ligamenta! band wide; 

. §ligh~ly inclined, and marked by faint, tenuous strire or scratches. 

. This species is associated· at Presque Isle Stream with shells having a broader, less deep. 

· ventral margin, to which may be applied the name variety lata. 

Locality: Chapman sandstone, abundant in the sandstones andsomeshaly layers on Presque 

Isle Stream (localities 1099 A, 1099 L) and 2! miles west of Presque Islo Stream (locality 

1099 B3 ), Chapman Township, Aroostook County, Maine. 

U. S. National Museum_, catalogue Nos. 59808, 59809. 

1 Meek and Hayden, Report on the invertebrate Cretaceous and Tertiary. fossils of the upper Missouri country: Rept. U. S. Geol. Survey of 

Territories, vol. 3, p. 68, 1876. 
MOLLUSCA. 215 

Oomparisons.-Myalina ma(ureriana.very closely resembles Olionychia excavata Ulrich, from 

the higher Ordovician beds at Riehmond, Ind., it species which differs frmn the normal Clionychias 

in having the muscular scar situated much lower down (at the midheight ·and just back of the 

center) and apparently undivided. The hinge line of 0. excavata is also shorter than usual, 

giving the shell a more vertically ·elongate appearance. In all these characters this Ordovician 

species agrees with },fyalina rnaureriana. The genus Clionychia, however, is described by 

Ulr.ich,t its founder, as having a linear ligament; and the ligament in all the species described 

and figm·ed is n1uch narrower than in Myalina maureriana. Olionychia excavata Ulrich also 

differs in son1e minor points of outline from M. maureriana; the concave portion of the anterior 

margin .is 1nuch longer and the shell is proportionately somewhat wider. 

The English Ludlow shell figured by Salter 2 as Mytilus mytilimeris (Conrad) bears some 

resemblance in outline to. M. rnaureriana but is much more oblique, the erect form of the Maine 

shell easily distinguishing it from tho English fossil. 

The original "Inoceramus mytilimeris" Conrad ,a from the shaly limestone~ of the Helderberg group [New Scotland] of New York, is ereot and has an outline closely similar to that of 

Myalina maureriana. Conrad's shell, however, is ventricose and has a prominent apex and 

belongs to Mytilarca or to Plethomytilus. 

Among the Myalinas M. maureriana is closely related to the Eo-Devonian M. goeensis 

Kayser, the higher Devonian },f. egregia Whidborne, the Mississippian M. subquadrata Shumard, and the late Permian so-called Promyalina hindi Kittl, from all of which it differs in 

having the anterior margin more convex and the forward ·extremity of the shell much higher. 

There are also other nlinor points of distinction from each of these species. 

MYALINA MAURERIANA sp. nov. var. LATA var. nov. 

Plate XVIII, figures 7, 9, 10, 12; Plate XIX, figlire 28. 

Associated at Presque Isle Stream with the lligh, narrow typical forn1 of Myalina maureriana above described, and nearly as abundant, are s.ome wider shells characterized by the broadly 

outward-cm·ying n1argin of the shell below and in front of the· u1nbonal region, the relative 

proportion of the length to the height being greH,ter than in },f. '"!'aureriana. Excepting for 

this characteristic wide bulging out of the lateral margins and the consequent shallowing and 

broadening of the ventral margin and greater proportionate length, the variety agrees with 

the typical form. In the erect outline, short hinge,· anterior margin convex for the greater part 

of the height and protruding in advance of the beak, shell closed and· apparently equivalved 

or very nearly so, depressed convexity, n1uscul~r scars, pallial line, and ornamentation, both 

forms are alike. Intermediate forms occur but are rare. 

Lo.cality: Chap1nan sandstone, Presque Isle Stremn, Chapn1an Township, Aroostook 

County, :Maine. :More than a dozen specimens have been found at Presque Isl~ Stream, where 

it is abundant, along w~th the typical form. · 

U. S. N at.ional Museum, catalogue No. 59810. 

MYALINA MAURERIANA sp. nov. var. PTERINlEOIDES (Clarke). 

Plate XIX, figures 24, 27. 

'11848. J{ytilus mytilimeris (not Conrad). Salter, Geo~. Survey Great Britain Mem., vol. 2, p. 365, pl. 20, fig. 7. 

I. .. ucllow: Golden Grove, Uandilo (not May Hill or Dudley). 

1907. J{yalina pterinreoides. Clarke, New York State Mus. Bull. 107, p. 214, figs. 

Lower Devonic: Presque Isle Stream, Chapman Township, Aroostook County, Maine. 

Clarke's name "·pterin::eoides" may be used in a varietal sense ·to include specin1ens of 

Myalina.maureriana th~t are more oblique than the typical form. The tY}).ical forms are ·~y 

' Ulrich, E. 0., New rmd little-known Lamcllibronchiata from tho Lower Silurirm rocks of Ohio: Ohio Goo!. Survey, vol. 7, p. 651, pl. 51, figs. 4, 5, 

1894. "Upper bods qf tho Cincinnati group, Hichmond, Ind." 

2 Salter, J. W., Geol. Survey Great Britain Mom., vol. 2, p. 365, pl. 20, fig. 7, 1848. . 

s Conrad, T. A., Observations on tho Silurirm and Devonirm systems of the United States, with descriptions of new orgrmic remains: Acad. 

Nat. Sci. Philadelphia Jour., vol. 8, p. 246, pl. 13, fig. 10, 1842 (read Jan. 18, 1842). "Middle Silurian shale," Helderberg Mountain rmd ncar 

Schoharie. N.Y. · 
216· FAUNA OF THE CHAPMAN SANDSTONE OF MAINE. 

far the dominant representatives of the species in the Chapman sandstone, as Clarke recognized 

in the descriptive text of his "species." The more oblique shell figured as Myalina pterimeoides 

.rriay therefore be considered the variety, and the specific name may be applied to the characteristic form of the species. Myalina maureriana var. pterimeoides may possibly prove identical 

with the "Mytilus mytilimeris Conrad" cited by Salter froni the English Ludlowian Silurian. 

, Locality: Chapman sandstone, Presque Isle Stream (localities 1099A, 1099L) and 2! miles 

west of Presque Isle Stream (locality 1099B3),.Chapman Township, Aroostook County, Maine. 

U. S. National Museum, catalogue Nos. 59812, 59813, 59814. 

Family MODIOLOPSIDJE Fischer. 

Genus MODIOMORPHA Hall. 

The genus Modiomorpha was founded by Hall 1 in December, 1869. It was described in 

1885 as follows: 2 

Modiomorpha Hall. Type, Pterinea concentrica Conrad. Shell equivalve, very inequilateral, subovate in outline, 

largest posteriorly. Anterior end rounded, forming a projecting lobe of greater or less extent beyond the beak. The 

valves are crossed obliquely by a more or less distinctly defined cincture passing from the beak to the base, and constricting the basal margin. Beaks small, compressed. Surface of the shell marked by rugose or undulating concentric · 

strire. Hinge furnished with a strong wedge-form tooth in'the left valve and a corresponding cavity in the right. No 

lateral teeth have been observed. Ligament external, attached to the thickened margin of the shell, which is longitudinally grooved for its receptlon. Anterior muscular impression situated within the anterior extension of the shell. 

Posterior impression large and superficial, situated on the posterior slope. Pallial line simple. Example~: M. concentrica (Pl. XXXVI, figs. 1-18), M. mytiloides (Pl. XXXVIII, figs. 1-16) .. 

The genus was later revised and the internal struct.ure more profusely elucidated by 

Beushausen,3 who has shown that only a few among the German Eo-Devonian species referable 

to Modiomorpha have the dentition described by Hall-that is, a single tooth in the left valve 

fitting in a socket in the right valve. According to Beushausen an additio~al socket for the 

reception of a tooth of the right valve is commonly found behind the tooth of the left valve; in 

a few species .the structure is reversed, the tooth being in the right valve and the socket in the 

left. The dentition is therefore highly variable. The ligament is shown by Beushausen, and 

also by Ulrich, to be internal, not external. 

The agreement in superficial expressio!l between Modiomorpha and the older genus Modiolopsis is so remarkable that Ordovician species of Modiolopsis are practically indistinguishable 

externally from Devonian species of Modiomorpha. The Ordovician species referable to 

Modiolopsis s. str. are regarded as edentulous by Beushausen, Ulrich, and others, whereas 

Devonian shells of this type have been found to be conformable with Modiomorpha Hall. 

Hence Modiolopsis is apparently unknown in the Devonian, and the distinction commonly 

accepted is that the upper Paleozoic modiolopsoids are dentate ( = Modiomorpha), 'whereas 

the lower Paleozoic shells of this type are edentulous and conformable with l\1odiolopsis. · 

N ever:theless modiolopsoid shells from the Ordovician· occasionally show traces of l\1odiomorpha-like dentition. 4 In the Ordovician n1odiolopsoid shells of the middle Western States 

the tooth in the left valve described for jfodiomorpha concentrica is mentioned by Ulrich as 

occasionally not entirely lacking, but "rather it is but little dovolopod, since an obscure thickening of the hinge plate between the muscular impression and the beak is noticeable in many 

species of Modiolopsis" from these Ordovician beds. In the Ordovician beds of France, also, 

among the normally edentulous modiolopsoids, an occasional species shows l\1odiomorpha-like 

dentition (Modiolopsis dollfussi 5), and as low down as the Cambrian one of the earliest modiolopsoids, · M. thecoidesl\1atthew, 6 has a thin hinge platform and the appearan.ce of a socket in 

1 Hal~,James, Preliminary notice No.2 of the fossillamellibranchiate·shells of the Upper Helderberg, Hamilton, Portage, and Chemung groups, 

December, 1869; republished with 16 additional pages, January, 1870. 

• 2 Hall, James, Paleontology of New York, vol. 5, pt. 1, p. xxiii, 1885. 

a Beushausen, Louis, Die Lamellibranchiaten des rheinischen Devon: K. preuss. geol. Landesanstalt Abh., new ser., vol. 17, pp. 11-15, 1895. 

4 Ulrich, E. 0., Geology of Minnesota, vol. 3, pt. 2, p~ 504, 1894. 

5 Bigot, A., Note sur quelques pelecypodes des gres siluriens del'ouest dele France: Soc. geol. France Bull., 3d ser., vol. 17, pp. 791-796, pl. 22, 

1889. 

o Matthew, G. F., Preliminary notice of the Etcheminian fauna of Newfoundland: New Brunswick Nat. Hist. Soc. Bull. 18 (vol. 4), p. 191, 

pl. 1, fig. 7, 1899. . . 
MOLLUSCA. 217 

the right valve. In the Siluria,n Guelph dolomite of Ontario, .Goniophora crassa Whiteaves 1 

is a n1odiolopsoid with a well-defined c'ardinal tooth or fold and is therefore referable to Modiomorpha. l-Ienee it must be apparent that the dentate modiolopsoids ( =Modion1orpha I-Iall) 

are by no 1neans confined to thE) upper Paleozoic but also pass down into the lowest rocks and 

are coextensive with the supposedly edentulous modiolopsoids. This brings up the question, 

Are the latter really edentulous and distinguishable fro1n Modiomorpha ~ Complications arise 

frmn the fact that I-Iall, in his original description of Modiomorpha in 1869, stated that he 

thought he had observed in :Afodiolopsis modiolaris, the genotype of Modiolopsis, a dentition 

si1nilar to that occurring in the group now associated about Cyrtodonta-Cypricardites; so that 

Fischer, on page 990 of his ''1\{anuel," describes Modiolopsis as having one to four cardinal 

teeth and one or two posterior laterals and distinguishes Modiomorpha from :Modiolopsis by the 

absence of posterior laterals and the occurrence of only one wedge-shaped tooth in the left valve 

and a socket in the right. This supposed distinction between Modiolopsis and Modiomorpha is 

repeated by Nettelroth. 2 HoweYer, the great majority of authors describe the Ordovician shells 

referable to Modiolopsis as edentulous. Few species of such shells are reported in which the 

binge line has been observed, and such as have a hinge line generally appear to be edentulous, 

never with the Cypricardites type of dentition. Hence, if ~!odiolopsis modiolaris Hall is synonynlous with Cypricardites Conrad, the name l\1odiolopsis will have to be confined to the firstmentioned species called l\1odiolopsis in the list cited by the author when describing the 

genus, 3 which are not Cypricardites, and these shells, it is believed, will be edentulous or nearly 

so ( =l\1odiolopsis of authors). On the other hand, the consensus of opinion seems to be that 

when I-Iall in 1869 described the supposed dentition of Mocliolopsis and J.l/. modiolaris he had 

son1e other nonmocliolopsoicl shell at band. In either case the name l\1odiolopsis becon1es 

avn,ilable for edentulous Inocliolopsoicl shells, which are the more common, at least in the lower 

Paleozoic. 

l\1ost Ordov-ician modiolopsoid shells have little or no trace of teeth; in the upper.Paleozoic,. 

shells hav-ing the 1nodiolopsoid shape are generally dentate and agree with Modiomorphn Hall, 

mncnd. Beushausen. l\1odion1orphoicl (or dentate-n1ocliolopsoid) shells, howev-er, occur throughout the Pn1eozoic, apvarently as far clown as the Can1brian, but in the Ordovician such shells 

generally lack the broader hinge platfonn, and the dentition is less strongly developed than in 

l\1odi01norpha. Ulrich has pointed out the fact that the Ordovician Inocliolopsoids also ha,~e a 

nmTow linear ligmuent, sometim.es intern:al, son1etin1es external, whereas in true l\1odimnorpha 

the liga1nent is very 1nuch broader. Both Beushausen and Ulrich regard the liga1nent of 

l\1ocliomorpha as being internal, a view opposed to that of I-Iall. Although there seen1 to be 

gradations between l\iodion1orpha and l\1odiolopsis, l\1odimnorpha n1ay be regarded as hav-ing 

a stronger hinge than l\1odiolopsis, both as regards dentition ancl. liga1nent; and the typical 

fot·n1s of l\1odiolopsis are edentulous. · 

"l''he range of J\llodion1orpha is from Upper Ordovician ( ~) to Carboniferous. The great bulk 

of the upper Paleozoic shells of these types belot1g to Modimnorpha and those of the lower 

Pnleozoic to Modiolopsis. Modimnorpha as currently interpreted is a dominant lmnellibranch 

genus of the Dev-onian. · 

Beushausen has shown that the predominant type of dentition in l\1odionlorpha includes 

two cardinal teeth in the left Yll~lve and one in the right. In number, position, strength, and 

genernl developn1ent the teeth are comparable with those of the genus Matheria Billings/ which 

has 11 years' priority ov-er Modion1orpha. Billings describes Matheria as follows: 

•rrru1svcrsc; cquivalv'c; inequilatcral; beaks ncar the anterior end; dorsal and ventral margins subparallel; two 

small obtuse cardinal teeth; two muscular impressions; ligament external. 

The only species described by Billings is M. tener, from the Trenton limestone of Blue Point, 

Lake St. Johns. Ulrich 5 records four or :five species, all small and all from the American Trenton 

li1ncstone (Ordovician) except :A1odiolopsis recta Hall, which is fron1 the Niagara group (Silurian). 

1 Whiton.vos, J. F., Paleozoic fossils of Canada, vol. 3, pt. 1, p. 9, pl. 2, fig. 3, 1884. 

2 Nottolroth, Henry, Kentucky fossil shells: a monograph of tho fossil shells of the Silurian and Devonian rocks of Kentucky, p. 216, 1889. 

a Hall, James, Paleontology of Now York, vol.. 1, p. 157, 1847. 

• Bflllngs, Elkanah, Canada Goo!. Survey H.ept. Progress for 1857, p. ISS, fig. 18, 1858. 

a Ulrich, E. 0., dp. cit., p. 563. 
218 FAUNA OF THE CHAPMAN SANDSTONE OF MAINE. 

Although Modiomorpha Hall was described as having an external ligament, Ulrich (1894) 

and Beushausen (1895) maintained that the ligament is really internal, and this character will 

serve to distinguish Modiomorpha from Matheria, in which the ligament is decidedly external in 

a fairly long open escutcheon behind the beaks. 1 Ulrich 2 also calls attention to the external 

ligament of Matheria, which is well illustrated in M. rugosa Ulrich. 

Whether the ligament is external or internal in Modiomorpha is therefore a matter of some 

little consequence. Ulrich 3 says: 

Another feature is observed in Modiomorpha concentrica that may be of importance, namely, the hinge plates 

posterior to the beaks * * . * extend inwardly and at the same time diverge, probably for the reception of a strong 

internal ligament, the removal of the thin plate leaving a sharp slit a little within the cardinal edge of casts of the 

interior. The value of the character is to be tested only by its persistence in other species referred to Modlomorpha. 

Beushausen 4 also calls attention to a long excavation on the inner margin of the hinge line, 

which might be mistaken for a long posterior lateral-tooth socket were it not for the fact that it 

occurs in both valves. Beushausen .. s figures of Modiomorpha elevata Krantz 5 clearly indicate 

an internal ligament, the occurrence of which in Modiomorpha he strongly emphasizes. Moreover, in the only uncrushed Modiomorpha known preserving the exterior of the cardinal line with 

both valves in conjunction ( Modiomorpha submissa Barrois 6

) the dorsal edges of both valves 

meet and close the shell, so that the ligament must have been internal. Although the interior 

is unknown, the fossil has the exterior form of Modiomorpha or Modiolopsis. Examination of 

large numbers of Modiomorpha concentrica, M. macilenta, }.f .. mytiloides, and other New York 

Devonian species showed in none of them any positive evidence of an external ligament, but the 

material was not well enough preserved to warrap.t the assertion that the ligaments are internal. 

There is, therefore, evidence sufficient to suggest that the ligament of Modiomorpha is internal; 

but unfortunately for such an assumption, Hall figures what seems to be an external escutcheon 

in Modiomorpha macilenta 7 M. aifinis ,S M. mytiloides, 9 and }.1. concentrica. 10 These specimens, 

however, are mostly internal molds, and it is not impossible to consider the supposed escutcheon 

as the impression, on the internal mold filling in the .shell, of the convex ~ase of an internal 

ligament; indeed, in view of Ulrich's and Beushausen's studies, such an explanation seems probable. If Modiomorpha really has an external ligament, as stated by Hall, then its dentition as 

elucidated by Beushausen shows that it is synonymous with the earlier genus Matheria Billings, 

which has two teeth in the left valve and one in the right. Modiomorpha Hall would possibly 

then be restricted in a subgeneric sense. to the shells which have only one tooth in the left valve 

and apparently only a socket and no tooth in the right valve. But the studies just cited seem to 

indicate that Modiomorpha has a true internal hinge and is therefore distinct from ¥atheria. 

Two other genera in main characters like Modiomorpha differ from Modiolopsis in the 

presence of strongly developed cardinal teeth. Curiously enough, both of these genera were 

founded in the same year and were given the same name (Modiolodon). The Modiolodon of 

Ulrich 11 includes some American Ordovician marine modiolopsoid shells having two or three 

strongly radial cardinal teeth in each valve. The Modiolodon of N etschayew 12 includes some 

Russian fresh-water ( ?) Permian modiolop~oid shells having two or three cardinal teeth in 

each valve, but differing from the American Ordovician shells in having the teeth horizontal 

instead of radial. Both genera differ from Modiomorpha in having more numerous cardinal 

teeth. 

1 Compare Billings, Elkanah, op. cit., fig. 18 A. 

2 Ulrich, E. 0., op. cit., pl. 36, fig. 30. 

a Idem, p. 504. 

4 Beushausen, Louis, op. cit., pl. 1, fig. 11. 

5 Idem, pl. 3, fig .llc. 

a Barrois, Charles, Fauna du calcaire d'Erbray, Loire-Inferieure: Soc. geol. Nord Mem., vol. 3, p. 176, pl. 12, figs. 2a, 2b, April, 1889. 

1 Paleontology of New York, vol. 5, pt. 1, pl. 39, fig. 21, 1885. 

s Idem, pl. 37, fig. 14. 

9 Idem, pl. 38, fig. 13. 

10 Idem, pl. 36, fig. 13. 

u Ulrich, E. 0., The Lower Silurian Lamellibranchiata of Minnesota: Geology of Minnesota, vol.3, pt. 2, p. 521, Jtme 16, 18:!4; New and littleknown Lamellibranchiata from the Lower Silurian rocks of Ohio: Ohio Geol. Survey, vol. 7, pt. 2, p. 652, 1894 (subsequent to Jw1e 16, 1894; not 

1893, date of title-page). ' 

12 Netschayew, A.,.Die Fauna der permischen Ablagerungen des ostlichen Theils der Europaischen Russlands [in Russian]: Soc. Naturalists 

Imp. Univ. Kazan Works, vol. 27, pt. 4, pp. 239 et seq., 1894 (month of publication illlknown; preface bears date March 1, 1894). It is interesting 

to note that several apparently edentulous modiolopsoid shells fro:n the Permian are called Modiolopsis in this work. 
MOLLUSCA. 219 

MonrOMORPHA cf. M. PROTEA Clarke. 

Plate XXI, figure 16; Plate XXVI, figure 14. 

cf. 1907. Jlfodiornorpha protea. Clarke, New York State Mus. Bull. 107, p. 220, upper figure (not lower figure= 

.~f. aroostooki sp. nov.). 

J"ower Devonic [Chapman sandsto:ne]: Edmunds Hill, Chapman Township, Aroostook County, Maine. 

A couple of fragments of a :Modiomorpha found in loose blocks of the Chapman sandstone 

on Edmunds Hill indicate a depressed species of transversely rectangular form, with cardinal 

line long, nearly straight, and ascending very slightly, nearly parallel with the basal margin, 

which is alrnost straight. The posterior margin is retrorse. The shell is depressed, rn.ther 

flat, and n1arked by a conspicuous umbonal ridge. The ornamentation is pronounced on the 

internal1nold 0 "sculpture cast n) where it consists of tenuistriate lines of growth occasionally 

strengthening into narrow concentric undulations: 

Locality: Chapman sandstone, Erlmunds Hill (locality 1099 C'), Chapman Township, 

Aroostook County, Maine. 

U.S. National Museu1n, catalogue No. 59815. 

MOJDIOMORPHA AROOSTOOK! sp. nov. 

Plate XXI, figures 2-7; 10-13. 

1907. J1fodiornorpha protea (pars). Clarke, New York State Mus. Bull. 107, p. 220 (lower figure only). 

J,ower Devonic: Presque Isle Stream, Chapman Plantation, Aroostook County, Maine. 

cf. 1907. Jfodiornorpha vulcanalis (pars). Clarke, idem, p. 219 (left figure only). 

Lower Devonic [Chapman sandstone]: Edmunds Hill, Chapman Plantation, Aroostook County, Maine. 

In one of the layers of the Chapman sandstone on Presque Isle Stream occurs in abundance 

more or less crushed and n1acerated shells and internal molds of a large spec.ies of either Cypricm·della or Modion10rpha. These shells or molds are usually found with both valves in conjunction, but in this condition, though abundant, they are too fractured, crushed, or otherwise 

imperfect for description. A well-preserved sculpture cast of a left valve from this layer of 

rock is taken as the type of the species },f. aroostooki. ·It is equivalved, inequilateral, closed. 

The length of the shell is li tirnes the height; the maximu1n length is situated at the inferior 

third of the height and the 1naximun1· height is situated indefinitely· posterior to the middle. 

The beaks, which are at the anterior fifth or slightly farther back, are directed fonvard; they 

are depressed to the hinge line and do not protrude beyond it. The anterior end of the shell 

is well developed, and the for"rard extremity is nearly opposite the midheight of the shell. 

Just in front of the beaks the antero-dorsal margin is faintly concave. Ventrally the anterior 

margin swings backward in a shallow curve into the ventral margin. In the type specimen 

and in one or two other specimens there is a faint constriction or straightening of the ventral 

margin bnck of the middle; but in the majority of specimens the ventral margin is slightly con-

'7ex throughout, without trace of byssal insinuation or constriction. The ven.tral extremity of 

the shell is near tlie posterior end. The ventral margin in the postventral region recurves in 

a broad swing into the 1~etrorse posterior margin. The posterior rnargin is convex throughout, 

vertical for nearly the lower half and swinging back in the upper half at an angle of 120° to 

135° to the hinge line. Ilinge extremity subangular. The hinge line is gently arched and is 

equal in length to only three-fourths the height of the shell, or three-fifths the ·totalleng~h of 

the shell; it. ascends slightly in its· anterior half and descends a little in its posterior half. 

Owing to the descending ventral margin the shell expands in height posteriorly. Specimens 

with both valves in conjunction are usually compressed and show a prominent postumbonal 

ridge, but the type specimen and some others show no umbonal ridge. The body of the shell 

is slightly inflated above the midheight and descends in a broadly arched surface to the 

ante:i·ior margin and to the forward half of the ventral margin. The greatest depth of the 

shell is situated above the middle-at the midlength, two-fifths the height below the hingeand is equal to a fourth the height in each valve in the uncompressed condition. The depth 

of the compressed specimens, with both valves in conjunction, is only a:bout one-third the 

height. 
220 FAUNA OF THE CHAPMAN SANDSTONE OF MAINE. 

Ligament internal. A narrow incision occurs on the internal mold just below the line 

exte:p.ding from the beak toward the hinge extremity, and becomes obsolescent before reaching 

the hinge. At first sight this incision resembles the impression of a posterior lateral tooth or 

socket, but the structure occurs on the molds in both valves at the same height, and the two 

ridges do not meet, but slightly diverge. 

~ o posterior lateral teeth or cardinal teeth are visible. The muscular scars are both large 

and deeply impressed. The anterior scar has a height of 8 to 10 millimeters or nearly onefourth the height of the shell. It is situated close to the anterior margin, much closer than 

to the beaks. A small deep retractor scar is usually observable in the concave space in front 

of the beak. The posterior scar has hardly twice the linear din1ensions of the anterior scar. 

It is situated near the posterior margin and extends down to or slightly beyond the midheight 

of the shell. The pallial line is simple and moderately strong. It begins at the antero-ventral 

corner of the anterior scar and ends on the posterior margin of the posterior scar, leaving the 

greater portion of· both muscular scars within the line. The pallial line is radially striate in 

its posterior portion. Shell substance very thick. 

The surface is covered with coarse concentric strim of growth, strongest posteriorly. 

A small specimen has a height of 29 millimeters and a length of 41.75 millimeters. The 

type specimen, a large individual, has a height of 40 millimeters and a length of 56 n1illin1eters, 

which is only slightly larger than the usual siz~ of the specimens. 

· The distinguishing· features of this ~ossil are its high form, with length equal to about 

1} tin1es the height; beaks well back, .commonly at the interior fifth or farther back; welldeveloped anterior end; faint expression, or in fact, usual absence of ventral insinuation; 

retrorse posterior margin; hinge line less than height of the shell; large muscular scars; posterior scar barely twice the dimensions of the anterior and extending down to the n1idheight 

or lower; coarse concentric strim of growth . 

. Locality: Chapman sandst<;me, Presque Isle Stream,_ at the end of Tweedy road (locality 

1099 L), in a layer 150 feet below the top of the section at this point, Chapman Township, 

Aroostook County, Maine. 

. U. S. National Museun1, catalogue ,No. 59816. 

Oomparisons.-The type specimens present some reseinblance to the New York Han1ilton 

shell Modi.omorpha alta Hall/ from which, however, they are easily distinguished. Jf. alta has 

· a much more fully, developed ventral insinuation and a s1naller anterior end. In general pro- . 

portions, general character of the ventral margin, and relative size and position of the muscular 

scars, M. aroostooki bears some resemblance to Jfodiomorpha complanata Hall, fron1 the Onon.:.. 

daga ("Corniferous") limestone of New York, but Hall's species is larger and has the 

umbones farther forward. 

Clarke 2 described under the name Jfocliomorpha protea two distinct species fron1 the Chapulan sandstone. One form, illustrated in the upper figure, is a narrow, transversely elongate 

shell with long hinge line, apparently from the Edmunds Hill locality. To this transversely 

elongate form I would restrict the name Jfodiomorpha protea Clarke. The second species is 

illustrated in Clarke's lower figure and is from Presque Isle Stream. In proportions, 1nanner 

of preservation, and general aspect it agrees with Jf. aroostooki, and it comes from the san1e 

locality. Clarke's specimen, as figured, shows the ventral margin ascending to the postventral 

extremity rather more strongly than is usual in this variable species . 

. The convex ventrai m_argin and the general shape of the shell suggest the genus Anodontopsis, and the fossils n1ay really ·be congeneric with Anodontopsis maccoyiana (see Pl. XXIV, 

fig. 16), rather than with the genus Modiomorpha. Indeed, the solitary specimen (fron1locality 

1099 L) identified with Anodontopsis maccoyiana and showing the cardinal teeth may perhaps 

be a young individual of · Jfodiomorpha aroostooki. · 

1 Hall, James, Paleontology of New York, vol. 5, pt. 1, p. 278, pl. 37, figs. 1-2, 4-12, 15, 16, 1885. 

2 Clarke, J. 1.1., New York State Mus. Bull. 107, p. 220, 1907. 
MOLLUSCA~ 221 

MoDIOMORPHA sp. indet. 

A fragment of a Modiomorpha in the collections shows a rounded oval species, with anterior 

end oval, high, but very short; ventrn1Inargin convex throughout; shell expanding in height 

posteriorly; anterior n1useular scar large; surface evenly rounded. The fragment represents 

a species about 35 1nillimeters in height, with a general resemblance in outline and appearance 

to the New York Onondaga (" Corniferous ") limestone species Modiomorpha com1Jlanata Hall 

or ll1. schoharie Hall,t but 'it is too imperfect for closer determination and description. 

l\10DIOMORPHA (cf. ENDODESMA) CHAPMAN! sp. nov. 

Plate XX, figures 1-7. 

Shell large, closed, equivalve, very inequilateral, transversely extended, rectangulartrapezoidal. Greatest height one-third the length fr01n the front; greatest length about onethird the length from the oase. Length nearly twice the height, the dimensions varying from 

60:31 n1illimeters t.o 70:36.5 1nillimeters. Beaks broadly depressed, directed forward, situated 

one-seventh to one-ninth the length from the anterior extremity. Cardinal line posterior to 

the beaks, very long, one-third to three-sevent.hs greater than the height of the shell; slightly 

convex; rising slightly fr01n the beak to the point of n1aximum height, thence gently declining 

to the posterior margin so that the posterior extremity is only about one-ninth or one-tenth 

the height below the umbo. Cardinal extremity angular, obtuse. Posterior margin retrorse, 

straight, or slightly convex from the cardinal extremity to the point of maximun1 length, 

including a distance equal to about half the length of the cardinal line; postero-basal region 

rounded angular, the upper portion and the lower or postbasal margin forming an obtuse 

angle of about 120°; the upper side of the posterior n1argin is about twice as long as the lower. 

The lower side curves off rather abruptly into the basal margin, which is broadly though vei·y 

slightly insinuated, almost straight for a distance equal to about the length of the cardinal line, 

to which it is parallel, thence rising forward in a broad curve to the anterior extremity, which 

is evenly rounded, though the upper portion has a shorter radius of curvature than the lower. 

The 1nost forward part o:f the shell is at the midheight. The anterior portion is separated 

fr01n the umbones by a short concave lunule. Isolated single valves have a depth equal to 

two-sevenths the length. The point of greatest convexity in well-preserved specimens is 

posterior to the middle on the rounded postumbonal ridge, about one-fourth the height of the 

shell below the cardinal line, occasionally near the midheight. The umbones are broad, convex, 

and depressed upward and forward; the beaks are in curved. There is no cleady defined postmnbonal angulation, this portion of the surface as far as the posterior basal n1m·gin being broadly 

rounded. The ce1~tral area of the shell is broadly insinuated, very slightly concave or flat to a 

point just below the beaks, where the surface descends into the anterior portion. 

The surface is covered with faint concentric lines of growth, occasionally aggregated into 

undulating concentric ridges or folds. These folds. are best developed on the anterior portion, 

particularly just m1der tli,e lunule. There are no traces of radiallin~s. Neither muscular nor 

pallial scars have been observed in any of the specimens, which are nearly all internal sculpture 

casts or internal molds. · 

The average shell is about 61 millimeters long, and each valve is between 8 and 9 millimeters 

deep. The largest specim.en figured is 36.5 millimeters high and 71 millimeters long. 

The present forn1s are remarkable among the .modiomorphoid shells, for the cardinal line 

which, instead of rising posteriorly as is common, is almost parallel to the basal margin or 

slightly reclining posteriorly. Other characteristic ·features are the obt'usely angular (not 

broadly rounded) cardina,l extremity; the retrorse, nearly straight upper posterior margin.; 

the transversely elongate outline,· with length twice the height; the extreme anterior point 

at about the n1idheight; the broad insinuation; the absence· of muscular scars; and the ornamentation obsolescent over the general surface but aggregated into concentric folds under the 

well-developed lunule. 

1 Hall, James, Paleontology of Ne~ York, vol. 5, pt. 1, pl. 34, figs. 13, 14, 1885. 
222 FAUNA OF THE CHAPMAN SANDSTONE OF MAINE. 

In the specimens from the locality west of Edmunds Hill the postumbonal slope to the 

cardinal line is. slightly steeper than it is in thos'e from Edmunds Hill. Consequently the point 

of greatest depth of the valve is about one-fourth the height below the cardinal line in the specimens from the locality west of Edmunds I-Iill, whereas in those from Edmunds Hill the point of 

maximum convexity or depth of the valve is generally nearer the n1idheight. 

Locality: Chapman sandstone, common at Edmunds Hill and west of Edmunds Hill, Chapman Township, Aroostook County, Maine. 

U.S. National Museum, catalogue Nos. 59817, 59818. 

Comparisons.-The species more or less closely resembles the common early Mississippian 

.Modiomorpha hyalea Hall 1 in its transversely elongated outline, with length barely less than 

twice the height the "parallel" cardinal and basal margins, with the cardinal margin slightly 

reclining, the absence of scars, and in the surfa,ce ornamentation. In the Maine forms, however, 

the beaks are much more anterior (only one~eighth the length) from the anterior margin, compared with one-third the length in M. hyalea, and the cardinal line 'is therefore proportionately 

much longer. The extreme anterior point is at or above the midheight in the Maine specimens; 

in M. hyalea it is below the midheight. The two forms are specifically distinct, though closely 

associated in the same generic or subgeneric group, which differs from the normall\1odiomorpha 

in having a transversely elongated outline with cardinal and basal margins very nearly parallel, 

and in having the cardinal line slightly reclining. 

One of the nearest allies to Modiomorpha (? Endodesma) chapmani is Salter's Mytilus 

platyphyllus var. (3, 2 from the Tilestones of South Wale~, which, however, has a more pronounced ligamenta! groove, an ascending, not reclining cardinal line, and the anterior end 

lower dorsoventrally than in the Maine form: 

The Ordovician genus Endodesma was founded by Ulrich 3 for modiolopsoid or modiomorphoid shells without muscular or pallial scars; with the length twice the height or more, and 

with the cardinal line not ascending, but, instead, parallel with the basal margin or very slightly 

reclining, and with a wide sinus. There is no escutcheon,4 the ligament is internal, and, in the 

type species (E. cuneatum Ulrich), a long internal posterior septum or ridge is developed under 

the cardinal line-presumably for the attachment of the ligament, though in the other species, 

except possibly in E. undosum Ulrich, 5 no such ligamenta} septum is apparent. This group of 

species, including Endodesma compressum Ulrich, 6 Endodesma orthonotum (Meek and Worthen), 7 

and Endodesma gesneri (Billings) 8 forms a series of Ordovician shells to which the Maine species 

under discussion bears close resemblance. In the same group may also be included the Silurian " Modiolopsis" antiq_ua Barrande (pars), noted below. In all there is the same peculiar 

expression caused by~ the broad umbones, with the beaks only about one-eighth the length fron1 

the front; the maximu1n height about one-third the length from the front; the cardinal line 

slightly convex, almost straight, and parallel with the basal margin, or very slightly declining, 

but never appreciably ascending; the angular or subangular cardinal extremity and retrorse, 

slightly convex, or nearly straight upper posterior margin;. the broad, oblique, shallow, undefined ventral insinuation; the distinct but broadly rounded, not carinated umbonal ridge, with 

the point of maximum depth situated on it above the midheight; the short anterior lunule and 

absence of conspicuous posterior ligamenta} groove; the absence of muscular scars; and similar 

obsolescent concentric ornamentation. With this group of shells the species at hand appears to 

be congeneric, and for that reason the generic name Endodesma has been used, though cogni~ 

zance has been taken of the fact that the internalligamental septum occurring in the original 

1 Hall, James, Paleontology of New York, vol. 5, pt. 1, p. 292, pl. 41, figs. 2~0, 1885. 

2 Salter, J. W., Geol. Survey Great Britain Mem., vol. 2, pt. 1, p. 364, pl. 20, fig. 14 (cet. excl.?), 1848. 

a Ulrich, E. 0., The Lower Silurian Lamellibranchiata of Minnesota: Geology of Minnesota, vol. 3, pt. 2, p. 525, pis. 36, 37 (in part), June 16, 

1894. 

t Endodesma postlatum Ulrich (idem, p. 527, pl. 37, figs. 5, 6), from the upper Galena (Ordovician) of Dubuque, Iowa, probably does not belong 

to Endodesma, for not on!_v is the cardinal line ascending, but, in addition, an escutcheon-like groove is developed for the ligament; the species is 

much shorter than all the other Endodesmas. 

5 Idem, pl. 36, fig. 38. 

a Idem, pl. 36, figs. 35-37. 

7 Idem, pl. 37, figs. 1, 2. 

s Idei:n, pl. 37, figs. 3, 4. 
MOLLUSCA. 223 

type species of Endodesma has not been observed in the present species nor, indeed, in mostof 

the Ordovician Endodesmas. 

Morcliomorpha (Endodesma?) chapmani is easily distinguished, superficially, from this group 

of Endodes1nas by being proportionately shorter; the. length is barely twice the height, whereas 

in the Ordovician species :it is more than twice and as much as· three times the height. 

In the upper Silurian of Arisaig occurs a group of three species similar to the Ordovician · 

Endodesn1as nmned, but having a few irregular radial strire in addition to the concentric marking. These Arisaig specie:s are Orthonota incerta, 0. simulans, and possibly also 0. speciosa, all 

described by Billings.1 

Among the other fossils which may in some respects be regarded as sin1ilar to ]{odiomorpha 

(Endodesma?) cha1Jmani Jmay be mentioned the Eo-Devonian J1egalodon curvatus of Krantz 

(pars) ,

2 fr01n the Siegen graywacke of Menzenberg, in which, however, the umbones are much 

higher and n1ore inflated, the cardinal line declines more rapidly, and the umbonal ridge is less 

broadly rounded than in t.he Maine species. 

Tho Sanguinolites sp. of Reed, 3 from the Bokkeveld sandstone of Ceres, Cape Colony, is 

also similar, but its cardinal line is slightly conca':e instead of slightly convex, the surface is 

less insinuated, the umbones are n1ore tumid, and the anterior extremity is n1uch smaller than 

in tho Maino species. 

Finally n1ay bo 1nenti.oned ]{odiolopsis antiqua Barrande,4 ranging fron1 the Silurian (etage 

E 2) to the Konieprussian Eo-Devonian (etttge F 2

), some forms of which, particularly those shown 

in Barrande's figures 9 and 10 fron1 the Silurian etage E 2, are with difficulty distinguishable 

fr01n ].f.odiomorpha (Endodesma?) chapmani. Barrande's species, however, is, like the Ordovician Endodesn1as previously discussed, more elongated than the Maine species and the umbones are also slightly more anterior. The Bohemian specimens just mentioned are apparently 

congeneric with the Ordovician group of Endodesma discussed in tho preceding pages; and, 

together with Billings's Arisaig shells, indicate the continuance of the genus Endodesma to 

and apparently through the Silurian. If the :Maine forn1 ia, as seems apparent, to be regarded 

as congeneric with the Ordovic~an group of Ulrich's species of Endodesma referred to, the Silurian species 1nay serve as a. connecting link in the stratigraphic interval between the Ordovician 

and the Chapman sandstone. 

Genus GONIOPHORA Phillips. 

The generic name Goniophora was proposed by Phillips 5 in 1848 for· the Silurian Oypricardia cymbreformis Sowe:rby. In the n1idst of some broad generalizations on the systematic 

position of the lower Paleozoic lan1ellibranchs, with special reference to Conrad's Orthonota 

and the lower Paleozoic Cypricardias, regarded as nearly allied to Mytilus and ~1odiola, Phillips 

stated: · 

If, as I suppose, Cypricardia e1pnbmjonnis be distinct, generically, and include species of the Mountain limestone, 

the name Goniophora seems suitable. It is, however, doubtless a mytiloid shell. 

The genus Goniophora was thus founded \vithout an:y indication whatever of any diagnostic characters, nor was the tjpe precisely indicated. The two or more forms called Oypricm·dia cymbrefm·mis by Sowetby· and authors (one form from the "Lower Old Red" at Felindre, 

the second from the Upper Ludlow at Ludlow) are apparently not cospecific; indeed, they are 

not known to be strictly eongeneric. Phillips 6 himself gave the nan1e Goniophora cymbreformis 

to shells of this general type, ranging fron1 the W enJock shales through the Tiles tones, and one 

might easily infer that the types of Phillips's Goniophora were Carboniferous (Mountain limestone) shells like Goniopho1·a rhombea, rather than Oy1Jricardia cymbreformis. 

Considering the meager description of the genus, the indefiniteness of the types, and the 

obscure position of its publication in the midst of a paragraph of generalizations on other fossils, 

1 Billings, Elkanah, Paleozoic fossils of Canada, vol. 2, pt. 1, pp. 130-131, pl. 8, figs. 2, 4, 3, respectively, 18i4. 

2 Naturh. Vcr. prcnss. Hhcinliindc Vcrh., vol. 14, p. 161, pl. 11, fig. 4a (not fig. 4b), 185i. 

s South African 1\fus. Annals, vol. 4, pt. 6, p. 254, pl. 31, fig. 4, 1904. 4 Barmnd9, Joachim, SystOmc silurien dn centre de Ia BohOmc, pt. 1, vol. G, pl. 260, box IV, figs. 2-11, 1881. 

n Phillips, John, 'l'he Malvern Hills compared' with the Paleozoic districts of Abberley: Geol. Survey Great Britajn 1\fem., vol. 2, pt. 1, p. 264, 

1848. 

6 Idem, p. 267. 
224 . FAUNA OF THE CHAPMAN SANDS',I'ONE OF MAINE. 

it is no wonder that the genus Goniophora was· at first entirely overlooked. Curiously enough, 

McCoy 1 discusses to some length the genera Orthonota Conrad, Cypricardites, etc., and the 

same fossils which -first attracted the attention of Phillips, but does not mention Goniophora. 

McCoy unites these fossils under one generic name-his Orthonotus, altered from Conrad's 

Orthonota...:.._and gives a short generic desoription. The first species described under the genustherefore strictly the genotype-is Sowerby's Oypricardia cymbreformis. There is no recognition nor mention of Phillip's's name Goniophora, founded four years before, although McCoy 

frequently refers to Phillips's work on the Malvern Hills. However, it seems that the term 

Orthonotus has no greater claim than Goniophora to be applied to Oypricardia cymbreformis, 

for the reason that Orthonotus was applied by McCoy to three different shells (Orthonotus 

cymbreformis = Goniophora; Orthonotus nasuta = Modiolopsis; Orthonotus semisulcatus = ~Grammysoidea) representing three widely separated genera; that he gave no explicit designation of the 

genotype; and, finally, that the generic description of Orthonotus given by ~1cCoy was so general as to be in itself of small value. The priority of four years possessed by Goniophora Phillips, 

1848, over Orthonotus McCoy, 1852, must therefore be considered sufficient cause for the reten-. 

tion of the former name in preference to the latter, unless, indeed, it can be shown that the shells 

called Orthonotus cymbreformis by McCoy are not congeneric with those designated Goniophora 

cymbreformis by Phillips. This has not yet been shown, so that we must, at least for the present, 

regard Orthonotus McCoy, 1852, as a strict synonym of Goniophora Phillips, 1848. 

The term Goniophora was recognized in 1854 by Salter,2 who mentions .Goniophora cymbreformis as being one of the dominant members of the Upper Ludlow fauna, but he gave no 

description of the genus, nor of any of the internal or diagnostic characters of the type species. 

The Sandbergers, when they wrote their classic work on the fossils of the Rhenish series 

in Nassau,3 seem, like McCoy, to have been utterly unaware of the existence of the genus Goniophora, for they described their now well.:.known Goniophora acuta (not Hall, 1870). as· a Cypricardia, without in any way mentioning the name Goniophora .• 

In 1864 Honeyman 4 mentioned but did not describe a fossil, called Goniophora cymbreformis, from the upper Arisaig beds of Nova Scotia. 

As pointed out 'by Barrande, Chenu does not· mention Goniophora in his "Manuel," and 

Hall,5 in 1870, seems not to have recognized the term, for he described under the generi0 name 

Sanguinolites a large number of species which he later referred to Goniophora. 

In 1874,6 for the first time, the generic name Goniophora was used for species other than 

G. cymbrejormis. The Arisaig shell called Goniophora cymbrejormis by Honeyman was described 

as G. consimilis by Billings, who also described as new·the species Goniophora transiens, G. 

bellula, and G. mediocris, from the upper Arisaig (late Silurian), as well as G. mediocris/ from 

the Gaspe limestone No. 8 at Gaspe, Quebec, the name G. mediocris being unintentionally 

applied to two different species. All these forms have the angular umbonal ridge commonly 

regarded as characteristic of Goniophora. Billings did n"ot give any description of the genus, 

nor did he indicate any important inte~n~;~-1. or other diagnostic genetic characters.; in fact he 

was not quite sure of the correctness of his usage of t4e term .Goniophora, for he said: 8 

The- genera Orthonota (Conrad), 1841, Sanguinolites (McCoy), 1844, and Gqniophora (Phillips), 1848; seem to be 

all closely related to .each other. The following references to these genera are, therefore, to be regarded as merely 

provisional. 

He then described and referred five species to Orthonota, two to Modiolopsis, and four to 

Goniophora. Billings's contribution is important as being the first general adoption of the 

now well-known term Goniophora, and also b.ecause he used the term not only for the short, 

t Sedgwick, Adam, and McCoy, Frederic~;:, British paleozoic rocks and fossils, 1852-1855. 

2 Murchison, R. 1., Siluria, 1st ed., p. 135, pl. 23, 1854. 

a Sand berger, Guido and Fridolin, Versteinerungen des rheinischen Schichtensystems in Nassau, 1850-1856. 

• Honeyman, D., On the geology of Arisaig, Nova Scotia: Geol. Soc. London Quart. Jour., vol. 20, p. 344,1864. 

5 Hall, James, Preliminary notice of the fossillamellibranchiate shells of the Upper Helderberg, Hamilton, and Chemung groups, pt. 2, pp. 

35-43, January, 1870. 

. o Billings, Elkanah, On some of the fossils of the Arisaig series of rocks, Upper Silurian, Nova Scotia: Paleozoic fossils of Canada, vol. 2, pt. 1, 

pp. 134-137, pis. 8, 9, 1S7~. 

1 Idem, p. 50, fig. 21. 

s Idem, p. 129. 
MOLLUSCA. 225 

square or trigonal, highly inflated shells of the type of the original G. cymbreformis and ·of G. 

consimilis, etc., but also for those much flatter and transversely elongate forms represented by 

G. t?·ansiens Billings, G. hamiltonensis (I-Iall), G. chemungensis (V anuxem), and G. carinata 

(Conrad). '"ro Billings is due the credit for the general acceptance and prevalent usage of the 

tern1 Goniophora. 

In 1875 'Voodward recognized the genus in his "Manual of conchology." Two years 

later Goniophora was accepted by Miller, 1 who used the term for I-Iall's Devonian Sang'l.tinolites 

acuta and S. hamiltonens·is, Conrad's Oypricardi~es rugosa, and all of Billings's Goniophoras. 

Miller's usage of Goniophora was repeated in 1878 by Bigsby. 2 

At about the same time I-Iall prepared his classic work on the Devonian lamellibranchs,3 

which did not appear in public until 1883. In September, 1878, at the Paris meeting of the 

Congres geologique I-Iall s:howed to Barrande the plates and pr~sumably the manuscript of this 

volun1e, so that in 1881, when Barrande issued his work on the lan1ellibranchs,4 he felt himself 

constrained out of courtesy to Hall to refrain from giving a description of the genus Goniophora. 

Barrande na1ned and figured seventeen species of what he regarded as Goniophora-three 

species (Goniophora retrorsa Barrande, G. scalena Barrande, and G. zephyrina Barrande) from 

etage E _1, .one species (G. zJhrygia Barrande) common to etages E 1 and E 2, eleven species confined to etage E 2, none in etage F 1, and two species in the I-Iercynian.or etn,ge F 2 • Most of these 

species are not really Goniophoras. G. retrorsa, from etage E 1 ; G. phrygia, fron1 etages E 1 and 

E 2 ; and G. imperfecta, G. reluctans, G. soror, and G. testis, from etage E 2, are radially ribbed 

schizodiform shells which belong apparently in Barrande's genera Matercula (Ma,minka) and 

Amita (Tetinka). G. sco:lena, from etage E t, is comparable with fonns of the Lower Devonian Kochia Frech (=Onychia Sandberger) and resembles externally illrich's genera Plethocardia and Whitella,5 as does also G. minax, from etage E 2 • Of the seventeen species named 

and figured by Barrande, only five can with any degree of certainty be referred to Goniophora. 

These are G. binotata, G. media, G. pugio, and G. rara, all four from etage E 2 (equivalent of 

Aymestry and Guelph), and G. secans (under which several distinct species are apparently 

aggregated), from the Konieprus etage F 2 (Hercynian). 

In 1883 appeared the advance or preliminary issue of Hall's work, dealing with the Devonian (Onondaga to Chemung) lamellibranchs of New Y ork,3 and in 1885 the work was conlple.ted by n. descriptive text and published in its final form. In this work, more than 35 years 

after the genus Goniophora was founded, appears the first description of the genus. · 

The main features of Goniophora, as described by I-Iall, are the strong angular ridge extending from the beak to the postinferior margin; truncate posterior extremity; long, straight hinge 

line; rhomboidal or trapezoidal outline; broad undefined sinus over the central or anterior part 

of the shell constricting the basal margin; and the concentric ornamentation, with, in a few 

species, radial lines between the sinus and umbonal ridge. With regard to the hinge and muscular structures, it should be emphasized that Hall's description of the genus was drawn up 

fron1 An1erican n1aterial, chiefly his Goniophora glauca of the Hamilton, and not from G. 

cymbreformis (Sowerby), the Silurian type of the genus Goniophora. According to Hall, 6 there 

nrc no lnteral teeth, and only a short oblique cardinal fold or tooth in the left valve and a corresponding depression· or socket in the right valve. The ligament is external, strong, and inclosed 

in n, well-developed escutcheon; anteriorly there is a deep lunule and well-developed lunette. 

The nnterior muscular sear is feebly impressed, fairly large, and surmounted by a small retractile scnr; the posterior sear is hardly ever discernible, but is larger and is situated on ~he postumbonul slope. 

I-Inll described a large number of species of Goniophora fron1 the "Corniferous," I-Iamilton, 

Portage (Ithacn shale n1mnber), and Chemung, and his beautiful figures have helped to 1nake 

the genus well known. 

1 1\:lillor, S. A., 'l'ho American Paleozoic fossils, p. 192, Cincinnati, Ohio, 1877. 

s Bigsby, J. J., Thesaurus dovonlco-carboniforus, 1878., 

a Enll, Jomes, Paleontology of New York, vol. 5, pt. 1. 

• Barmnclo, Joachim, SysWme sflurien du conti'e do la Boh~me, pt. 1, vol. 6. 

50245°-NO. 89-16--15 

5 Ulrich, E. 0., Geology of M:irmosota, vol. 3, pt. 2, pp. 

564, 575, 1894. 

o Hall, James, op. cit .. pl. 46, figs 13, 14. 
226 FAUNA OF THE CHAPMAN SANDSTONE OF MAINE. 

Though this genus is commonly regarded as having no posterior lateral teeth, as exemplified in some of the more elongated and flatter Devonian shells referred to Goniophora (G. glauca, 

etc.), the original type, as represented by G. cymbreformis (Sower by), from the Tiles tones of 

Felindre,t has posterior laterals, to judge from the figure cited. Traces of a posterior lateral 

are also apparently indicated in Goniophora perangulata Hall 2 and in the flatter G. applanata 

Beushausen.3 . At first sight it would hardly seem credible that the small, short, highly inflated 

shell of the Silurian cymbreformis type, apparently showing one or two long, well-developed 

posterior laterals, should be. congeneric w'ith the more depressed, transversely elongated type 

represented by Goniophora glauca Hall, G. hamiltonensis (V anuxem), and G. bipartita (F. Roemer), 

having no posterior laterals. Not only does Sower by's figure of the Tilestone Goniophora cymbreformis seem to indicate the existence of posterior laterals, but McCoy, 4 in his description of 

Sowerby's species, says that the hinge line is "slightly elevated (the margins si1nple and erect 

[meaning, presumably, without escutcheon], with a moderately slender lateral tooth extending 

a little below it)." On the preceding page, under the description of the genus Orthonotus, 

McCoy states that there is an internal cartilage plate running beneath the long hinge line, and 

a few lines below he again emphasizes this point in stating that these shells "n;mst not be confounded with * * * Grammysia .(Vern.) and Sanguinolites (McCoy), in which th.e dorsal 

margins are inflected at right angles"-that is, producing a strong escutcheon. "They are, in 

fact, a sort of elongate Edmondia," continues McCoy .. Edmondia has an internal ligamental 

septum, as in Mytilus. Thus it would appear that Goniophora (Orthonotus McCoy) cymbreformis 

(Sowerby) seems to have posterior laterals .and an internal ligament, but no escutcheon. The 

real type of Goniophora may, therefore, be a very different shell from that indicated by the 

prevalent interpretation of the genus. It is, in fact, quite possible that Goniophora, based on 

Sowerby's Oypricardia cymbrejormis, is more closely identifiable with Mecynodus of authors 

than with Goniophora of authors. Unfortunately these English Silurian lametlibranchs have 

been wholly neglected since the pioneer days of Murchison, Sowerby, and McCoy, so that hardly 

anything is known of the real structure of the fossils. The absence of English specimens at the 

present writing makes it impossible to shed any further light on the matter. 

Therefore, although I suspect that the real types of Goniophora cymbreformis n1ay be shells 

having apparently two long posterior laterals in the right valve (as figured by Sower by), and 

one in the left 0) valve (as stated by McCoy), and thus being, so far as known, congeneric with 

the shells included under the genus Mecynodon Keferstein (written Mecynodus by Beushausen), 

still, in the absence of more definite knowledge, I an1 conforming with the prevalent conception 

of Goniophora and regarding it as edentulous except· for the short diagonal cardinal in the left 

valve and the corresponding socket, with sometimes a small anterior cardinal, in the right valve. 

If there is an internal rather than external ligament in G. cymbreformis, as stated by McCoy, 

then G. cymbreformis must be quite distinct from both Mecynodon and Goniophora of authors. 

Finally, it may be stated that the apparent existence of lateral teeth in some forms of 

Goniophora seems to have been noted by Beushausen,S who, in his description of tllis featu:r.e 

in Goniophora, says: "Lateral teeth absent.. Toward the interior of the shell the hinge line is 

set off with a septun1 of which the impression on the internal mold is represented by a furrow. 

The ligament is external in a long groove behind the beak." Beushausen's mention of a "furrow" has very much the appearance of an attempt to explain Sowerby's figure in conformity 

with the common conception of Goniophora. Moreover, Beushausen's Goniophora applanata 6 

is apparently the only form indicated by him which shows this furrow below the hinge line, and 

this form is not known to possess an external ligament. The Goniophora perangulata of Hall, 

previously indicated as showing a sin1ilar furrow, has, however, a strong esc~tcheon and lunette, 

which places the species in Mecynodon. 

1 Murchison, R. L., The Silurian system, pt. 2, pl. 3, fig. lOa, 1839. 

2 Hall, James, Paleontology of New York, vol. 5, pt. 1, pl. 34, fig. 1, 1885. 

a Beushausen, Louis, Die Lamellibranchiaten des rbeiniscberi Devon: K. preuss. geol. Landesanstalt Abb., new ser., vol. 17, pl.l7, figs. 18-20, 

1895. 

1 Sedgwick, Adam, and McCoy, Frederick, British Paleozoic rocks and fossils, p. 275, 1852. McCoy's material was from the Tilestones of Horeb 

Chapel, Llandovery, South Wales; and from the Upper Ludlow of Burton and Brockton, near Wenlock. 

~ Beushausen, Louis, op. cit., p. 196. 

6ldem, pl. 17, figs. 18, 18a. 
MOLLUSCA. 227 

Drevermann 1 describes several forms of Goniophora and gives some interesting notes on 

the genus. Drevermann states among othe~ things that a long posterior septal ridge or tooth 

(posterior lateral) is present in "some species" of Goniophora in the left valve. 

Whidborne 2 n1entions a long posterior lateral tooth in his Devonian Goniophora obliqua frmn 

Woolborough, but the species is apparently not a Goniophora. 

I shall therefore foUow, temporarily at least, those authors, including Hall, N eumayr, 

Beushausen, and Drevern1ann, who regard Goniophora as being without posterior lateral teeth 

and as having prestnnably an external ligament. The two or three species of Goniophora present 

in the Chapman fauna are unfortunately too poorly preserved in these respects to shed any 

additional light on the su1bject. 

Anwng the shells most likely to be confused with Goniophoru, are those belonging to the 

genus Mecynodon Keferst.ein. 3 The following !s a translation fron1 the Germn,n of the original 

diagnosis of Mecynodon: 

Shell longish, thin [really rather thick, as pointed out by Beushausen ariel as may readily be seen from the 

figures of the species], concentrically striated or smooth, divided by a blunt or sharp diagonal keel into a front and 

posterior portion. Hinge without hinge plate; in each valve, almost parallel with the hinder margin, there is a long,. 

high ca.rdinal tooth, and in the right valva a deeper groove behind it; in the left valve, where the tooth is along the 

the cardinal margin, there js a groove in front of it. A long lateral tooth on the posterior portion of each valve; that of 

the right inclosing that of the left. Anterior muscular impression almost on the hinge line, deeply impressed·, 

especially the posterlor portion; just behind it is the deep imprint of a small pedal muscle. Posterior muscular scar 

somewhere near the middle of t.he posterior margin. Pallial impressio.1 simple. Ligament external, short. 

'l'he genus is foullded on species of Megaloclus of Goldfuss which have already been differentiated .into several 

groups by 'Von Gruenewaldt 4 a,t the instigation of Beyrich. 'l'he genus Mecynodon embraces the second and third 

gl'oups of Von Gruenewaldt. 

l(eferstein then describes ~1ecynodon carinatus (which must be taken as the genotype 

of Mecynodon), ~1. oblongus, and M. auriculatus-all three species fron1 the Eifelian limestone 

at Paffrath, described originally by Goldfuss under Megalodus. 

Keferstein describes the genus as having only one posterior lateral in each valve. As a 

1nn.tter of fact there are t.wo in the right valve inclosing the single posterior lateral of the left. 

Beushausen 5 describes the genus and the. type species M. carinatus Goldfuss as having two 

cardinals in each valve. This does not appear in the illustrations of the hinge structure of the 

fossils, except that the sn1all narrow depression in the right valve in front of the anterior tooth 

and between this tooth and the anterior muscular scar may be occupied by a small narrow tooth 

or ridge situated in the left valve between the anterior large socket and the muscular scar. 6 

~1egalodon oblongrts Goldfuss can not belong to Mecynodon, for it has two posterior laterals 

in the left valve, apparently three cardinals in the left valve and two in the right, and a surface expression entirely different from that of Mecynodon. Tllis species appears to be a Pleurophorus. The group o( 1.1. auriculatus also .should probably be separated from Mecynodon 

on account of the distinc1jjve superficial expression. · 

"l"he shells belonging to Mecynodon are rhomboidal in outline, with a typical goniophoroid 

umbonnl ridge in the type species. They have concentric markings and a general expression 

almost indistinguishable from several of the n1odifications of typical Goniophora, and the mus-· 

cular Inarkings and cardinal dentition are the same in each genus. Goniophora and :M:ecynodon are apparently distinguishable only on hinge features. Mecynodon differs in having two. 

well-developed long posterior laterals in the right valve, inclosing the one of the left valve. 

Posterior lat~rals are, as has been indicated, supposed to be absent in Goniophora, but. 

the typical figure of the typical G. cymbreformis 7 appears to show two posterior laterals in the 

1 Drevormann, l<~., Die Fauna dor Untorcoblonzschichton von Oberstadtfeld bei Daun in der Eifel: Palaeontographica, vol. 49, pp. 88 et seq.,. 

HJ02. 

2 Monograph of the Devonian fauna of the south of England, vol. 2, pt. I, p. 17,·pl. 3, fig. I, 1892. 

a Koforstoin, Christian, Ueber oinige doutsche devonische Conchiferen aus der Verwandschaft der Trigoniaceen und Carditaceen: Deutsch .. 

goo!. Gesell. Zcitschr., vol. 9, p. I58, 18J)7. 

4 DouJ;sch. goo!. Gesell. Zeitschr., vol. 3, p. 252, 1851. 

~ Boushauson, Louis, op. cit., pp. 188, 192-193. 

Bldom, pl. 16, figs. 17, 18 ( 1\f. carindtns); compare also thl:' anterior cardinals in 1V. oblongns Goldfuss, shown in Beusbausen's pl.16, figs. 25, 26 .. 

7 Murchison: H.. I., 'l'be Silurian system, pt. 2, pl. 3, fig. lOa, 1839. 
228 l<~AUNA OF THE CHAPMAN SANDSTONE OF MAINE. 

right valve inclosing one in the left, as in :Mecynodon. In G. cymbreformis, according to McCoy, 

the ligan1ent is internal and the cardinal margin not inflected: These two distinctions, if they 

really exist, will separate typical Goniophora from Mecynodon. The Devonian shells commonly 

passing under the name Goniophora _are generally without posterior laterals and are distinguishable in this respect from Mecynodon; but have apparently an escutcheon or a strongly 

inflected cardinal margin or both. (See G. hamiltonensis Hall, 1 . G. acuta Hall (not Sand berger), 2 

G. rugosa Hall/ G. modiomorphoides Grabau/ and G. secans Barrande 5 (only a short but broad 

escutcheon, beyond which the margin is not inflected). In :Mecynodon there is a well-developed 

though short escutcheoi). for the ligament, which is external, and the cardinal margin is usually 

inflected. There is also a very well developed lunule and lunette. 

In the American faunas Goniophora perangulata Hall, 6 from the "Corniferous" limestone, 

seems to be a Mecynodon. In Europe Mecyno.don occurs in the Middle Devonian of the Eifel 

and in England. · · 

The more depressed-convex, transversely elongated species of Goniophora resemble Modionlorpha in the muscular markings, cardinal detention, general outline, concentric ornamentation, and ventral insinuation and in the absence of posterior laterals, but Goniophora is 

easily distinguished by the presence of the angular umbonal ridge or keel and the usual change 

in ornamentation posterior to it. In the absence of the angular umbonal ridge and in the 

presence or absence of posterior laterals the group of Mecynodon auriculatus Goldfuss, M. concentricus Archiac and De Verneuil, etc., bears the same relation to Modiomorpha that the 

typical Mecynodon (group of M. carinatus Goldfuss) bears to Goniophora of authors. In the 

first pair the umbonal ridge is absent and the outline similar. In the second pair the angular 

ridge is present and the common outline is distinct from that of the first pair. The first member 

in each pair has posterior laterals; the second has not. 

_The features above mentioned also distinguish these Goniophoras from Cypricardella, which 

lacks both the angular umbonal ridge and the ventral insinuation of Goniophora. In Cypricardella the anterior muscular scar is much farther removed from the cardinal teeth than in 

Goniophora a~d Mecynodon, and there is generally no discernible pedal muscular scar. Cypricardella usually has the umbonal ridge fairly well developed, though not nearly so well as in 

Goniophora. 

In the European Triassic occur some small corbuliform shells (Nucula gregaria Munster/= 

Oorbula gregaria Schauroth; 8 Astartopsis (Myophoriopis) richthofeni Stur) 9 of rhomboid outline and highly inflated convexity, having a strong angular umbonal ridge; they are truncate 

and more or less finely striated posteriorly. These little shells are 'with difficulty distinguishable superficially from certain small Devonian Goniophoras such as G. (ex. Oypricardia?) 

acuta Sandberger 10 (not Hall) and G. (ex. Isocardia) crelata Sandberger, 11 fr01n the Rhenish 

Middle and Lower Devonian, and G. minor Hall/2 an Upper Devonian fossil fron1 the Ithaca 

shale n1ember of the Portage formation; but they differ in internal structlire. 

Hind 13 has prop~sed the new name Mytilimorpha to replace Goniophora Phillips, oil the 

ground that the latter is preoccupied by a generic name previously applied by Agassiz to some 

crinoids. As Agassiz's crinoid genus is Goniophorus, not Goniophora, the name Goniophora 

·should not be considered preoccupied. · Hind's Mytilimorpha is founded on the Carboniferous 

Goniophora rhombea, which is without posterior lateral teeth. Should the genotype of Gonio-

'Hall, James, Paleontology of New York, vol. 5, pt. 1, pl. 43, figs. 15, 17, 20,1885. 

~ Idem, pl. 43, fig. 2. 

a Idem, pl. 43, fig. 7. 

4 New York State Geologist Sixteenth Hept. (for 1896), p. 254, figs. 1, 2, 1897. 

5 Syst€\me silurien du centre de la Boh€\me, pt. 1, vol. 6, pl. 255, figs. 2, 9, 13, 1881. 

a Hall, James, op. cit., p. 293, pl. 34, figs. 1-6; pl. 42, figs. 1-2. 

1 Goldfuss, August, Petrefacta Germanire, pt. 2, p. 144, pl. 124, fig. 12, 1863. 

s Schauroth, C., Deutsche gcol. Gesell. Zeitschr., vol. 9, p: 120, pl. 5, fig. 17, 1857. _ 

9 Bittner, Alexander, Lamellibranchi11ten der alpinen Trias, pt. 1: K. k. geol. Heichsanstalt Wien Abh., vol. 18, p. 112, pl. 13, :fig. 10, 1895. 

Broili, Ferdinand, Palaeontographica, vol. 50, p. 217, pl. 27, figs. 3-14,1903. . 

10 Sandberger, Guido and Fridolin, Die Versteinerungen des rheinischen Schichtensystems in Nassau, p. 2(i3, pl. 27, fig. 12, 1850-1855. 

11 Idem, p. 260, pl. 27, fig. 11. · 

12 Paleontology of New York, vol. 5, pt. 1, p:305, pl. 42, figs. 4-6, 1885. 

ta IIind, Wheelton, A monograph of the British Carboniferous Lamellibranchiata, pt. 4: London P!i.leontogr. Soc. Pubs., vol. 53, p. 338, 1899. 
MOLLUSCA. 229 

phora (G. cymbreformis) bo found to possess posterior laterals, the name Mytili1norpha may 

be appliecl to those shells commonly called Goniophora which lack such teeth. 

The oldest known species of Go1;1iophora is the fossil called llfodiolopsis carinata I-I all, 1 

from the Trenton limestone (Ordovician) of Middleville, N. Y. (not Goniophora carinata (Conrad, 

1841), 2 from the Middle Devonian; the two species appear to be congeneric, however, and as 

I-Iall's specific name is therefore preoccupied, I would suggest the nan1e of G. trentonensis for 

I-Iall's Ordovician fossil). The next oldest species, G. speciosa, Hall, 3 occurs in the upper Niagaran (Silurian) shales of Vvald:ron, Ind. These two rare fossils are the only species of Goniophora described frmn the Ordovician and Silurian of the American continent except the Nova 

Scotian Silurian fo!·.ms. Ooniophora crassa Whiteaves, 4 from the Guelph dolomite of Ontario, 

Canada (equivalent of English Aymestry), is not a Goniophora; it is a n1odiolopsoid shell with 

a well-developed cardinal tooth or fold, and is therefore referable to ~Iodion1orpha flall. 

Beushausen 5 also has shown that the shell is not Goniophora. The species is still included 

in Goniophora by Whiteaves in his "Revised list of the fossils of the Guelph formation." 1\ 

Goniophora (Zubia (flail ~) 7 is doubtfully a Goniophora. The species occurs in the Manlius 

limestone of New York and also at Peach Point, Put-in-Bay Island, Lake Erie, and at Middletown,8 Ohio, in strata supposed to be of the same age. 

In Europe Goniophora is unknown in the Ordovician and n1akes its first appearance in the 

Gotlandian Silurian, in the brachiopod shales of which occurs· Goniophora carpomorpha (Dalman) .

9 This species is very si1nilar to G. cymbrejormis and was considered probably identical 

with it by Sowerby himself.10 Goniophoras occurring in the English Wenlock group, Lower 

Ludlow and Aymestry lim.estone, have been reported 11 as G. cymbrejormis Sowerby. In the 

Bohenuan Silurian Goniophora Inakes its first a.ppearance i:n etage E2, the equivalent of the 

Guelph and Aymestry. 

Beginning with the Upper Ludlow and T.llesto:p.e faunas,· in which Goniophora cymbreformis is an abundant and eharacteristic fossil, Goniophora is fairly common. G. cymbrejormis, 

of which the late Silurian Ooniophora consimilis Bill.ings, fron1 Arisaig, Nova Scotia, already 

cited, appears to be a synonym, is reported by Li:ndstron1 12 frmn Gotland and by Schmidtt 3 

from the island of Oesel. 

Goniophora attains the acme of its development throughout the Devonian, particularly in 

the Siegen and Coblenzian graywackes of the German Lower Devonian, from which 15 or 20 

species have been described, including the shells described and figured by Beushausen 14 as 

Leptodomus latus Krantz, L .. posterus Beushausen, L. barrosi Beushausen, and perhaps Oardiomo~pha aiata Sandberger, whi.ch may be a Mecynodon. The genus is also highly developed in 

the I-Iamilton or Middle Devonian of New York, fron1 which aln1ost as n1any species are known. 

The 1nen1bers of the genus are fewer and less abundant in the Upper Devonian. Goniophora 

continue into the British and Belgian "sub-Carboniferous." 

As to the distribution of Goniophora in America, attention has already been directed to 

Go'fl:i01Jhora, trentonensis nom. nov. ( = Modiolopsis (Goniophora) carinata IIall, 1847, not Conrad's 

sp., 1841), fron1 the Trenton limestone, and Goniophora speciosa flall, from the Silurian Waldron shale of Indiana. Gon-iopho'l'a crassa Whiteaves, from the Guelph dolomite, .is a Modio1 Hall, James, .Paleontology or Now York, vol. 1, p. lGO, pl. 35, fig. lla-c, 1847. 

2 Idem, vol. 5, pt. 1, p. 301, 1885. 

a Hall, James, Albany Inst. Tnms., vol. 10, p. 17, 1879; described and figured in Indiana Stato Geologist :Elcvent.h Hcpt., p. 317, pl. 27, figs. 

26, 27, 1881. 

• Whltoavos, J. F., Paleozoic fossils of Canada, vol. 3, pt. 1, p. 9, pl. 2, figs. 3-3c, March, 1884. 

& Uoushauson, Louis, Dio Lamollibronchiaton des rheinischen Dovon: K. preuss. goo!. Landesanstalt Abh., new ser., vol. 17, p. 19U, 189.5. 

o l'alcozoic fossils, vol. 3, pt. 4, p. 329, September, 1906. 

1 Whitoflolcl, R P., Gcol. Survey Ohio, vol. 7, p. 415, pl. 1, figs. 24-26, 1893. 

e Whitfield said "1\flddlctown, Marion County," but 1\:!iddlotown is in Butler County, a long distance from Mario1t County. 

o Cardites carpomorpllus Dalman, Acta Acad. Holmim, p. 372, pl. 4, fig. 2, 1824; Cardium carpomorpllum, Hisingcr, Petrificata Svccim, p. 63, 

pl. 19, fig. 5, 1837-1841; Goniophora carpomorpha, Lindstrom, Frogmcnta silurica, pl. 19, 1880. 

to Murchison, R 1., Tho Silurian system, p. 602, 1839. 

u Phillips, John, Tho 1\falvom Hills: Gcol. Survey Great Britain Mem., vol. 2, pt. I, p. 267, 1848. 

12 Nomina fossllium siluricnsium Gothlandi::e, p. 3, 1867. 18 Schmidt, Friedrich, Untersuchungen uclbcr dio silurische Formation von i<:::hstland, Nord-Livland unll Oescl: Archiv Naturk. Liv-, Ehstund Kurlands, 1st scr., vol. 2, pp. 173, 209, 1858. 

u Uoushauson, Louis, op. cit., pis. 24, 25. 

.. 
'230 FAUNA OF THE CHAPMAN SANDSTONE OF MAINE. 

morpha, not a Goniophora. Goniophora is unknown in America in the Salina formation 

(hydraulic limestones and shales), except for the Goniophora sp. indet. of Weller, 1 from the 

Decker limestone of New Jersey, which corresponds with the extreme top of the Salina formation and is just below the horizon of the Cobleskill limestone. The genus is also unknown in 

the Cobleskill limestone and the Rondout water lime. Goniophora dubia (Hall~) Whitfield, 

from the Manlius limestone of New York and from corresponding beds in Ohio, is doubtfully 

a Goniqphora. In the Upper Ludlow faunas of Arisaig, Nova Scotia, several species of Goniophora are very common. 

From the Helderberg and Oriskany faun~s of New York and their equivalents no Goniophora has yet been described, and· the genus, if it occurs at all, is very rare in these rocks. 

Schuchert 2 in his list of the Helderbergian fauna includes a Goniophora sp. nov. from the shaly 

New Scotland limestone of New York. Another undetermined form is doubtfully indicated 

by Weller from the Balmanites dentatus zone ("Trilobite beds") of the Port Jervis section. 

In the Lower Coblenzian fauna, or zone of Spirifer hercynire, Goniophora is represented 

by G. mediocris Billings,3 from the Grande Greve or Gaspe limestone No. 8 of Indian Cove, 

Gaspe, Quebec. 

In the Schoharie grit and "Corniferous" lin1estone Goniophora occurs occasionally; in 

the Marcellus shale the genus is extremely rare; in the Hamilton Goniophoras become very common, both in species and individuals, throughout New York State, occurring in the aren~ceous 

sediments of the eastern part of the State as abundantly as in the calcareous rocks of the western 

part. In the Tully limestone Goniophora is rare; it is unknown in the Genesee shale and in the 

Portage fo'rmation, except in the Ithaca shale member, where it is fairly common, the interesting 

little Goniophora minor HaU being a characteristic fossil of the upper half of the Ithaca member. 

Goniophora continues into the Chemung of eastern New York and is rarely found in the Chemung of central and western ·New York. 

No Goniophora is known from faunas higher than the Chemung in North America. The species described from the Warsaw shale under the name Oypricardella plicata and often cited under . 

the generic name Goniophora does not belong to that genus, but is more nearly related to 

Pleurophorus. 4 In Great Britain and in Belgium, however, Goniophora continues into the 

Carboniferous, being represented by Oypricardia glabratus Phillips,5 Oypricardia rhombea Phillips,6 

and Oypricardia acuticarinata Armstrong. 7 A~ditional references to these species are given by 

De Koninck 8 under Sanguinolites. In the heteromorphous assemblage of species ·included 

by De Koninck in the genus Sanguinolites, especially his Group I, the species with only a single 

radial carina, there are many forms externally similar to the Devonian fossils that commonly 

pass under the genus Goniophora. Besides the tlu;ee species just noted, the following are a 

few of De Koninck's "Sanguinolites" that are referable to Goniophora: S. bipartitus De Koninck,9 

S. prresectus De Ryckholt/ 0 and S. lyellianus De Ryckholt, 11 fron1 the Visean or etage III; and 

S. arigulatus De Koninck/2 S. cuneatus De Koninck, 13 and S. constrictus De Ko~inck, 14 from 

etage II. 

GONIOPHORA KAYSER! sp. nov. 

Plate XIX, figure 18. 

Length (54 millimeters) two and two-thirds ti1nes the height (20.5 millimeters); greatest 

length near the midheight. Umbones broad, incurved, depressed, hardly extending above 

1 Weller, Stuart, Paleontology of New Jersey, vol. 3, p. 246, 1903. 

2 Schuchert, Charles, Geol. Soc. America Bull., vol. 11, p. 286, 1900. 

a Billings, Elkanah, Paleozoic fossils of Canada, vol. 2, pt. 1, p. 50, fig. 21, 1874. 

c See Hall, James, Albany Inst. Trans., vol. 4, p. 18, 185G; Whitfield, R. P., Am. Mus. Nat. Hist. Bull., vol. 1, p. GG, pl. 7, fig. 39, 1882; and Hall, 

James, Indiana Dept. Geology .and Nat. Hist. Twelfth Ann. Rept., p. 341, pl. 30, fig. 39, 1883. 

· 6 ~Phillips, John, lllustrations of the geology of Yorkshire, vol. 1, p. 209, pl. 5, fig. 25, 1836. 

6 Idem, p. 200, pl. 5, fig. 10. 

1 Armstrong, James, Geol. Soc. Glasgow Trans., vol. 2, p. 28, pl. 1, fig. 3, 18G5. 

s De Koninck, L. G., Faune ·du calcaire carbonifere de la Belgique, vol. 3, pt. 5, pp. Gl, G3, G8, pl. 15, 18Ct' .. 

D Idem, p. 69, pl. 15, fig. 27. 

to Idem, p. G7, pl. 15, fig. 37. 

11 Idem, p. G4; pl. 15, fig. 39. 

12 Idem; p. 71, pl. 1G, figs. 4, 18. 

1a Idem, p. 71, pl. 1G, figs. 14, 15. 

u Idem, p. 72, pl. 16, fig. 17. 
MOLLUSCA. 231 

the cn,rclinol li11e; beaks situated between the anterior fourth and fifth, directed forward. The 

cardinnlline extends posteriorly in a straight line parallel to the base or longitudinol axis for 

a distance equal to about one and one--fourth or one and one-third times the height; the cardinal 

extro.m.ity appears to be broadly rounded and merges at the posterior fourth or fifth of the 

length of the shell into the posterior n1argin. The posterior margin makes an unsymmetrical 

curve, convex throughout, retrorse above, nearly vertical in the lower half. The extreme lower 

part of the posterior n1m·gin extends slightly forward, so that the extreme posterior point of the 

shell is at one-third or two-fifths the height above the base. The postventral extremity is 

nutrked by the foot of the umbonal carina and is slightly nasute, so that the posterior third of 

the ventrnl nutrgin is concave and rises anteriorly, though only very slightly so: The basal 

mm·gin as a whole is constricted or very nearly straight to a point below the beaks, from which 

it curves into the rounded anterior portion. The anterior n1argin is strongly rounded; the upper 

portion has a shorter radius of curvature than the lower, reaches to a point n1ore than two-thirds 

the height n,bove the base, nnd is separated fron1 the beak by a shallow lunule. The extreme 

anterior point of the 1nargin is at the midheight. The principal features of the convexity of 

the shells are the steep convex slope ab~ve and behind the carina, a slight concavity in 

front of and below the carin~a, depressed convexity over the central regions of the surface, thence 

declining in a 1nore strongly convex slope to the beak and anterior margin. The point of 

greatest depth of the valve is on the umbonal carina near the midlength, one-fifth or one-sixth 

the height below the cardinal lin«:l. This depth is equal to one-third the height (6.75 millimeters) of the single volve. Frorn the beak toward the midlength the surface is very steep 

or perpendicular to the cardinnl line, the slope. becoming more and uiore gentle posteriorly. 

'fhe Uinbonol cm·ina is well developed, sharp un1bonally, less so postveutrally. It is somewhat 

accentuntecl by the slight concavity in front of it and by the steep declivity posteriorly to 

the cm·clinal line and posterior mtargin. The carina is· not sigmoidal (except possibly at the 

lowest extremity, which is indistinct in the specimen) and extends in a shallow arch, convex 

with respect to the center of the surface. I-Iinge, muscular, and shell structures unknown. 

The surface ornamentation, so far as it can be described from au internal mold, consists 

of very faint, obsolescent, concentric lines of growth, leaving the specimen practically smooth. 

Length 54 millilneters, height 20.5 millimeters, depth of the left valve (the only specimen), 

6.75 millimeters. 

The distinguishing features of the genus are its transversely elongated nonoblique form; 

the length two and two-thirds times the height; the,long, straight, horizontal, cardinal line; 

the rounded posterior Innrgin, vertical in 'the lower half; the nasute postventral angle; the 

umbones depressed, beaks at the anterior fourth or fifth; dorsal carina convex, hardly sigmoidal; 

surface slightly concave il1 front of the carina, and steeply convex behind; d~pth of valve equal 

to one-third the height and one-eighth the length. 

I take pleasure in nnming this species· after Prof. Emanuel Kayser as a slight token of 

my deep appreciation of his many years of fruitful labor on the Devonian. The name may 

also Sf(rve to Cinphasize the very close relationship between this species and a species of the 

same genus described by Prof. 1\:ayser. 

Locality: Chap~an sandstone, west side of Edmunds Hill, Chap1nan Township, Aroostook County, :Maine. 

U. S. National Museun1, catalogue No. 59819. 1 

Oompar·isons.-'I'he species described above under Goniophora shows considerable resemblance to Kayser's GoniozJlwra trapezoidalis 1 from the. Taunus quartzite of ''Katzenloch." 

Tho two fonns agree in the elongate outline, with length two and two-thirds times the height; 

depressed un1qones and long eardil1alline, one and one-third or 1nore time:; the height; convex, 

curving posterior ntargin; nasutely extended postventral extremity; and convex, nonsigmoidal 

umbonal cm·il1a, with a convex slope back of it and an obscure concavity or depression in front 

of it. The Chapman fossil differs from G. trapezoidalis, however, in the following particulars: 

• Kayser, l~mnnuol, Uobor oiDige DODO Zweischaler des rheinischen Taunusquarzits: K. preuss. geol. Landcsanstalt Jahrb. 1884, p. 19, pl. 2, 

fig. 4, 1885. Soo also Boushauscn, Louis, Dl.e Lamollibranchiaten des rheinischen Devon: K. preuss. geol. Landesaustalt Abh., now ser., vol. 17, 

p. 205, pl. 17, fig. 34, 1895. 
232 FAUNA OF THE CHAPMAN SANDSTONE OF MAINE. 

The postinferior portion is slightly nasute and less extended than the European form; the 

lower half of the posterior margin is more nearly vertical; the cardinal line is shorter in proportion to the height; the anterior end is longer; and the beaks are at the anterior one-fo1,1rth 

or one-fifth, instead of at the anterior one-seventh. 

Goniophora lcayseri agrees with Roemer's G. bipartita, from the Siegen graywacke, in the 

nasute extension of the postinferio:r portion of the shell and the nearly vertical position of the 

lower half of'the posterior margin, but G. bipartita is much shorter, and the un1bones are situated much nearer the front than in G. lcayseri. · 

GoNIOPHORA OM;EGA sp. nov. 

Plate XXIV, figures 13, 15. 

Length (more than 56 millimeters, apparently ·about 60 millimeters)· about two and a 

half ·times the height (24 millimeters). Greatest length slightly below and near. the midheight; 

greatest height near the n1iddle. Umbones broad, very depressed, not extending beyond the 

cardinal line. The anterior end is destroyed in the type specimen, but the beaks appear to 

be at about the anterior fourth and directed forward. The cardinal line extends posteriorly 

in a slightly convex, nearly straight horizontal line parallel to the longitudinal axis and base 

for a distance equal to about one and three-fifths times the height of the shell. The postcardinal extremity is subangular and situated at the posterior tenth or twelfth of the length. 

The posterior margin is convex throughout, retrorse, the most posterior point being below the 

midheight. The lower half of the posterior. margin is approximately vertical. The postventral extremity is marked by the base of the umbonal carina and is apparently not nasute. 

The basal margin is nearly straight. The most striking features of the convexity are the steep 

convex slope back of the carina~ uninterrupted by any insinuation or flexure and a· broad, 

slightly concave depression marking the general s.urface of the shell and sloping markedly 

downward fron1 the elevated umbonalcar!na as far forward as the anterior end, which appears 

to have been convex as usual. The umbones are depressed and the slope frol)l the umbonal 

ridge to the ca:rdinal line, just back of the beaks, is steep but hardly vertical. ·The umbonal 

carina is sharp, especially in the lower half; it appears to be sigmoidal, convex in the upper 

portion, slightly concave toward the. middle, and straight in the lower half. The depth of 

the type specimen, a right valve, is 9 millimeters, or three-eighths of the height and three~ 

. twentieths of the length; the point of greatest depth is on the umbonal carina at the midheight, 

and at the· posterior third or two-fifths of the length of the shell. flinge and muscular structure unknown. The specimen at hand preserves the shell; this interesting feature in Goniophora, I believe, has never before been described. The shell is of medium thickness and is 

composed in the main of a porcelaneous or earthy and seminacreous, laminated calcium carbonate. The outermost layer is very thin, membraneo~s, rather continuous, and slightly 

different in color from the inner layers; it is much rougher than the inner l~yers and contains 

faint traces of fine and coarse lines of growth. This thin outer membrane may possibly have 

been the epidermal layer or pe:riostracum. It effervesces under acid though apparently somewhat less strongly than the inner layers. The latter are nacreous or semiporcelaneous, slightly 

or faintly vitreous, and composed of large, smooth, thin flakes; like the outer layer, they are 

of a pale-yellowish russet color. · No distinctly prismatic layer is observable. 

The surface is essentially smooth, especially posterior to the carina. Anteriorly there are 

indications of obsolescent lines of growth, occasionally aggregated into faint concentric ridges 

and hollows 1 millimeter or less in width. Length more than 56 millimeters, apparently about 

60 millimeters; height, 24 millimeters; depth (of the right valve), 9 millimeters .. 

The distinguishing features ·of this Goniophora are the length, which is two and a half 

times the height; the long, horizontal, very slightly convex hinge line, equal to one and threefifth times the height of the shell; the postcardinalextremity at the posterior tenth or twelfth; 

the·posterior margin r~unded convex throughout, with the lower half vertical; the straight or· 

concave ventral margin; the sigmoid carina, becoming sharper below; the convex surface back 
MOLLUSCA. 233 

of tho carina; the broadly concave general surface sloping downward from the carina to the 

nntcrior end, which is convex, as nonnal; and the practically smooth surface. 

Tlu·eo specimens of this species obtained since the foregoing description was written show 

tho chnrncter.istic broftd ventral concnvity, sn1ooth convex postun1bonal slope, shell structure, 

outline, ftnd sign1oidnl carinn as described above. Two of the specimens are 18 and 21 millimeters high, respectively. 

Locftl.ity: Chapman sandstone, ~: miles west of Presque Isle Stream·, Chapman Township, 

Aroostool<: County, :Maine. 

U. S. National ::Museum, eatalogue No. 59820. 

Oomparisons.-The nearest ally to this species is Goniophora kayseri, described nbove. In 

G. lcayseti the postcnrdinnl extremity is farther forward and more obtusely rounded than in 

G. omega, ftnd the postbasn.l extremity is n1ore nasute. In G. omega the carina is apparently 

sigmoid and becomes sharper below; in G. kayseri it is convex throughout and less sharp below 

than 1.nnbonal1y. The.n1ost important ·distinction observed is the broad concavity in G. omega. 

over the general sill-face in front of tho carina, extending over the central part of the shell to 

a point just below the position of the beak. In G. kayseri the central part is faintly convex, 

the concftvity being limited to a narrow space imn1ediately in front of the carin9.. The broad 

concavity is one of the n1ost ·distinguishing features of G. omega. The nearest allies in this and 

several other respects are Goniophora trigona I-Iall,1 from the Upper Devonian Chemung formation, near ~Franklin, Delaware County, N. Y., which differs chiefl:y in having the posterior 

slope concn.ve instead of convex, the umbones extending over the cafdinal line and the cardinal line shorter in proportion to t.he height of the shell .. The Goniophoras figured by I-Iall 2 

from the I-Iamilton of Schoharie Com~ity, N. Y., are also similar, but have the posterior margin 

n1ore abruptly truncate and straight and the posterior slope concave instead of convex. 

Genus SPHENOTOMORPHA gen. nov. 

A well-preserved interior 1nold of a modiomorphoirl shell from the Chapman sandstone of 

the Presque Isle Strean1 arett presents some peculiar features that seem to require generic as 

well as specific separation froin p:reviously described forms. On account of combination of 

characters of the two genera Sphe:tiotus und Modiomorpha the name Sphenotomorpha is proposed. Sphenoto1norpha differs from Modiomorpha in having the hinge line rigid, straight, 

not ascending, but horizontal or slightly declining; it also lacks the ventral insinuation or constriction chnrftcteristic of Modiomorpha and the modiolopsoids in general. The hinge features 

are those of Modiomorpha-a long, narrow escutcheon, with a low trin.ngular cn.rdinal tooth in 

the left Yftlv-e fitting into ft groove in the right. The external expression will at once distinguish .~phenoton1orpha from Morliomorpha. This external expression corresponds v.rith that 

of the well-known genus Sphenotus I-Iftll in outline, curvature, and n1arkings, but the ventral 

ins.im1fttion present in the common and characteristic species of Sphenotus is absent in Sphenotomorphlt. The hinge fe~tures are entirely distinct in the two genera, Sphenotus having 

two cardinals in the right valve and one or two lateral teeth, whereas 'Sphenotomorpha has 

only one cardino.l in the left vah'e, apparently no teeth in the right valve, and no posterior 

lftterals. The generic diagnosis is as follows: 

Shells having the superficial features of Sphenotus but without ventral insinuation and 

having the dentition of Modiomorpha I-IaU; transversely elongate, apparently cl,osed, equivalve, 

except thftt in the right valve there is generally a posterior longitudinal furrow and in the left 

valve an elevated ridge or rib let, between the umbona1 ridge and the hinge line; very inequilateral, length about double the height; ventral and dorsal n1argins parallel; the ventral margin convex, without insinuation; dorsal margin long, straight, horizontal, or slightly declining 

posteriorly; posterior margin truncate; anterior end rounded, short but dist.inct, and separated by ft small shallow lunule frmn the beaks, which are anterior, prosogyrate; convexity 

1 Hllll, Jmnos, Pllloontology o! Now York, vol. 5, pt. 1, p. 302, pl. 42, fig. 12; pl. 44, fig. 9, 1885. 

2 Idem, pl. 42, figs. 14, 15. Tho~o shells arc miBnamecl Goniophora subrci:ta Hall, for the originals of that species arc from the Chemung of Delawtuo County and aro figured on pl. 44, figs. 19, 21. Figs. 14 and 15 on pl. 42 show Hamilton shells apparently of the same species as that represented 

in fig. 11, pl. 42, and figs. 6-8, pl. 44; that is, G. carinata Conrad. 
234 FAUNA OF THE CHAPMAN SANDSTONE OF MAINE. 

·ni:oderate; umbonal ridge rounded, fairly prominent; obetween the umbonal ridge and the hinge 

line there occurs a slight narrow radial groove or ridge, the ridge frequently occurring in the left 

valve and the groove in the right valve. There is a long, narrow escutcheon for an external 0) 

ligan1ent and a low thick short" cardinal tooth in the left valve fitting into a socket in the right 

valve, but no other cardinal or lateral teeth. Muscular scars and pallial line unknown. OrnaInentation, concentric low obsolescent narrow ridges or undulations of growth. 

The type is Sphenotomorpha rigidula sp. nov., fron1 the Chapman sandstone. The species 

Sphenotus bodenbenderi Clarke/ from the Lower Coblenzian (Eo-Devonian) fauna of Rio Maecuru, 

Para, Brn.zil, appears to be cong.eneric, as does also Oytherodon? socialis Billings,2 from the 

late Silurian fauna n.t Arisaig, Nova Scotia. The geologic horizon of the genus appears to be 

uppermost Silurian and Lower Devonian. 

SPHENOTOMORPHA RIGIDULA gen. et sp. nov. 

Plate XXIV, figure 9. 

Length (30 millimeters) two and one-half times the height (12 millimeters); dorsal and 

ventral margins parallel, so that the greatest height is indefinitely near the middle, greatest 

length near the base. Umbones depressed, not extending beyond the hinge line, prosogyrate 

beaks situated between the anterior fifth and sixth, nearer the latter. Hinge line long, rigid, 

straight, ~orizontal, or slightly declining; equal in length to 1! or 1! times the height of the 

shell. Posterior hinge extremity di~tinct, subangular, very obtuse. The posterior n1argin 

is strongly ret.rorse; almost straight, as far down as the respiratory angle, making an angle of 

135° with the hinge li:r;te. Posterior extremity at the respiratory angle, at the inferior third ~f 

the height. Ventral margin nearly horizontal; not insinuated; convex throughout, though 

only ,slightly so over the greater portion; curving upward more strongly into the rounded 

postinferior or respiratory angle and into the rounded anterior end. The anterior end is lower 

than the posterior end but includes about three-fourths the height of the shell. There is a 

shallow, very. small lunule. The shell is of moderate depth; convex throughout, especially 

over the middle; slightly more depressed posteriorly, ventrally, and toward the umbones, 

though nowhere complanate or compressed. There is an undefined, broadly rounded umbonal 

ridge, prominent umbonally, less distinct lower down. There is· no ventral insinuation; 

between the umbonal ridge and hinge line there is a faint radial groove in the right valve on 

the internal mold. Point of greatest depth at the middle; depth of single right valve 2.85 

millimeters, or one-fourth. the height .. A narrow groove extends the length of the hinge line 

poste.rior to the beak, gradually tapering posteriorly, and apparently representing a narrow 

external 0) escutcheon. On the internal mold of the right valve there is a broad, low triangular or domelike elevation just beneath the beak, which apparently represents a similarly 

shaped single cardinal tooth in the left valve and a corresponding socket in the right. No 

evidence of any. other teeth is found. Muscular scars and pallial line not discernible. 

The internal mold shows evidence of concentric, obsolescent, low rounded undulations of 

growth. These undulations are strongest on the anterior end of the shell to a point below 

the umbones; posterior .to the rounded umbonal ridge· they disappear and the surface is 

essentially smooth. 

Type and only specimen, a right valve in internal mold, 30 millin1eters long, 12 n1illi1neters 

high, and 2.85 millimeters thick. 

The distinguishing features of the fossil are the transverse outline, length two and one-half 

times the height; parallel· basal and dorsal margins, the latter horizontal or very slightly 

declining, rigidly straight, and one and one-third times the height of the shell; basal margin 

slightly convex, not .insinuated; posterior margin retrorse, making an angle of 135° with the 

hinge line; posterior extremity at the respiratory angle in the lower third; anterior margin 

rounded and three-fourths the height; umbones between the anterior fifth and sixth; convexity 

. 1 Clarke, J. M., The Paleozoic faunas of Para, Brazil; Devonian Mollusca: Mus. nac. Hio de Janeiro Arch., vol.lO, pl. 8, figs. 25, 26; pl. 5, fig. 17, 

1899 (author's English ed., p. 58, 1900). o 

2 Billings, Elkanah, Paleozoic fossils of Canada, vol. 2, pt. 1, p. 138; pl. 8, fig. 12, 1874. 
MOLLUSCA. 235 

moderate, uniforn1, the shell nowhere insinuated or compressed except for an extremely faint 

radial groove between the hinge line and the umbonal ridge; umbonal ridge broadly rounded, 

hardly discernible; no muscular sears visible; low concentric undulations of growth, most 

conspicuous on the anterior end, the posterior slope nearly smooth; a long, narrow, but dis.tinct 

escutcheon (posterior ligamenta! groove), and a solitary short domelike cardinal tooth in the 

left valve and a socket in the right; shell apparently closed. 

Locality: Chapn1an sandstone, 2! 1niles west of Presque Isle Stream, Chapman Township, 

Aroostook County, ~1~1.ine, with Chonetes stTiatissimus. 

U.S. National Museun1, catalogue No. 59821. 

Gene1·ic and specific relations.--The generic position of this shell is perplexing. In the 

ligan1ent, single low cardinal tooth in the left valve and socket in the right valve, and transverse 

outline with rounded undefined mnbonal ridge, it would seem to find its nearest affiliations 

with Modion1orpha I-Iall; but the shell is easily distinguished from Modiomorpha and the 

modiolopsoids by the uniforn1 convexity below the un1bones and by the absence of any insinuation or compression. In the Inocliolopsoids also, the hinge line is ascending, the shell becoming 

mal'lwdly wider behind, unlike Sphenotomo?'pha rigidula. 

The outline of the present species is, with the exception of the ventral 1nargin, that of 

typical Sphenotus. The genus Sphenotus was founded by Hall/ who described it as follows: 

SI'HENO'l'US, n. g. (Typical species, Sanguinolites arcmjormis Hall and Cypricardia contracta Hall.) 

Shell equivalve, very inequilateral, elongate subtrapezoidal or cylindrical in outline. Anterior end short. 

Posterior end usually obliquely truncate. Beaks subanterior. Cardinal line long and nearly straight. Umbonal 

ridge defined, extending from the beak to the postinferior extremity. Postcardinal slope marked in all the characteristic species by a median ridge. Valves crossed from the beak to the base by a more or less defined, broad cincture, 

which often produces a constriction in thE: ventral margin. 

Sur.face marked by concentric strire of growth and rarely by fine radiating lines. In a single species (S. solenoides) 

tho surface is further ornamented by fine, :irregular, elevated vascular lines on the posterior half of the shell, especially 

above tho umbonal ridge. 

Hinge narrow, with two short, narrow cardinal teeth beneath the beak of the right valve, and with one or two 

extremely slender lateral tooth. Ligament external, contained in a slender groove along the cardinal line. Anterior 

musculnr scar strongly marked, situated close to the anterior mnrgin. Posterior scar shallow. Pallial line simple. 

Tho species united under the preceding generic description have been referred to several genera by various 

authors. 'l'he genus Snnguinolites, by an unwarrantable extension of its true characters and the disregard of the type, 

. has heretofore included many species of this group. Also, a few forms have been placed in the genus Allorisma. 

They differ from both those genera in the umbonal and postcardinal ridges, their tmpezoidal form, in the cincture 

crossing tho valves, and in the chamcters of the hinge. 

Examples: Sphenotus arcmformis, Pl. LXV, figs. 7-ll; Sphenotus contractus, Pl. LXVI, figs. 1, 3-9, ll-13, 15; 

Pl. XCIV, fig. 2. 

The genus includes narrow, transversely elongated shells with nearly parallel basal and 

dorsal1nargins, marked by a rather conspicuous umbonal ridge between which and the dorsal 

line occur one or occasionally two or n1ore radial grooves or riblets, or commonly one or more 

riblets in the left valve and the groove structure in the right valve. In Sphenotus contractus 

I-Iall, one of the type species of Sphenotus, there are in the right valve ''two short, narrow 

cardinal teeth, beneath the beak * *· * and one or two extremely slender lateral teeth." 

Thero is a long escutcheon. Sphenotus is easily recognized by its transverse outline with 

prominent u1nbonal ridge, and particularly by the longitudinal furrow or riblet between the 

umbonal ridge and cardinal line. This furrow or riblet is present in all the typical forms, 

though it is sometimes discernible only with difficulty. In Sphenotus, as in the n1odiolopsoids, 

there is a ventral insinuation or constriction. 

Sphenoto1norpha agrees witth Sphenotus in outline and superficial appearance, sharing 

with it the characteristic posterior riblet or groove, but Sphenotomorpha lacks the ventral 

insinuation or constriction of both Sphenotus and Modi01norpha. The posterior radial riblet or 

furrow is very faint. in SphenotomoTpha rigidula it is almost invisible, and is represented by 

a faintly impressed line midway between the un1bonal ridge and cardinal line or a trifle nearer 

the former. Clarke's figures of Sphenotus [SphenotomoTpha] bodenbenderi indicate a similar 

1 Hall, James, Paleontology of New York, vol. 5, pt. 1, p. xx:dii, 1885. 
236 FAUNA OF THE CHAPMAN SANDSTONE OF MAINE. 

extrem~ly faint posterior furrow in the right valve, whereas Billings's figure of Oytherodon 

[Sphenotomorpha] socialis shows a riblet in the lef.t valve. This would indicate that in Sphenotomorpha, as is common in Sphenotus, the posterior riblet is in the left valve and the furrow 

is fajnter and in the right valve, ·the two valves being otherwise apparently equal. 

Sphenotus bodenbenderi Clarke and Oytherodon? socialis Billings are included in Sphenotomorpha b.ecause of their agreement with the ri.ew genus in its superficial aspect, differing from 

Sphenotus in the convex, noninsinuated ventral margin. Their dentition is unknown at present. 

In the sphenotomorphoid aspect and convex noninsinuated ventral margin Sphenotomorpha 

agrees closely with the Carboniferous genus Pleurophorella of Girty/ but that shell is a closed 

allerismoid with strongly granulated surface and a deep lunule. P. papillosa, the genotype, 

seems to show a single dental socket under the beak of the left valve, according to Girty, who 

is, however, not certain of this feature.. In Sphenotomorpha the lunule is exceedingly small 

and the surface apparently nongranulose; there is a single cardinal tooth in the left valve with 

a socket in the right valve. 

Superfamily NAIADACEA. 

Family CARDINIIDJE Zittel. 

Genus· ANODONTOPSIS McCoy, 1852. 

The genus Anodontopsis McCoy is discussed at length in the present paper in connection with 

the genus Cypricardella (pp. 239-244). It is there pointed out that if the term Anodontopsis is to 

be used at all, it must be restricted in its application to shells congeneric with the Upper Ludlow 

Anodontopsis angustifrons McCoy, 2 .the genotype. Unfortunately, however, it is at present 

rather difficult to determine just what shells a:re congeneric with the genotype, because of 

uncertainty as to its real structure. 

Anodontopsis maccoyiana, described beyond, so closely resembles McCoy's genotype in outline, convexity, and ornamentation that the two ·might easily be considered as the same species. 

Because of this nearly specific identity, for the present I am referring the Chapman shells to the· 

genus Anodontopsis; future elucidation of the English type inay or may not prove· then1 

congeneric. 

If the Chapman; and British shells are regarded as congeneric, the genus Anodontopsis McCoy 

may be defined as including cyrtodontiform, concentrically striate, dimyarian shells having the 

umbones in front of the n1iddle and prosogyrate; the anterior 'end distinctly developed and 

round; the posterior portion of the shell expanding in height, 9wing to the ascending hinge line;. 

the posterior margin retrorse; the ventral margin rounded and without trace of byssal sinus or 

constriction. No lunette or escutcheon. Dentition unknown; but apparently the hinge plate· 

mu1?t have been thin, if developed at all. The shells conform in outline and general superficial 

expression with the Cyrtodonta-Cypricardites group but have no escutcheon; the hinge plate, 

if developed at all, is decidedly weaker than in that group; and the stronger posterior teeth of 

that group are certainly lacking. Anodontopsis is also more depressed than the gibbous and 

ventricose species of Cyrtodorita, etc. 

ANODONTOPSIS :MACCOYIANA sp. nov. 

Plate XXIV, figure 14; Plate XXVI, :figures 2, 3, 5, 6, 7, 10, 12, 13. 

ef . 1855. Anodontopsis angustifrons. McCoy, British Paleozo.ic rocks and fossils, p. 271, pl. 1, K, figs. 14, 15.' 

Upper Ludlow: Benson Knot and Kirkby Moor, Kendal, Westmoreland. 

Outline triangular or wedge-shaped, expanding behind; cyrtodontiform; total length of 

the hinge line, both in front of and behind the beaks, slightly less than. or barely equal to the 

height of the shell perpendicular thereto; beaks at approximately the ·anterior third, directed 

forward and not protruding above the hinge line. Anterior portion of the shell well developed; 

1 Girty, G. H., New molluscan genera from the Carboniferous: U.S. Nat. Mus. Proc. No. 1372, vol. 27, pp. 728 et seq., pL45, figs. 4-6; pl. 46,. 

fig. 5, June 1, 1904. 

2 Sedgwick, Adam, and McCoy, Frederick, British Paleozoic rocks and fossils, p. 271, pl. 1, K, figs. 14, 15, 1852. 
MOLLUSCA. 237. 

equal to 11 quarter or a third of the total length, and attaining four-sevenths to five-seyenths the 

total height. There is a dcfu1able lunule in front of the beaks; the anterodorsal n1argin swings 

into the posterior hinge line .in a broad curve. The anterior portion of the she1l is convexly 

rounded tln:oughout, with the shortest radius of c~vaturc anteroventrally, at the point whence 

tho nntcrior mnrgin descends in a broad arch into the ventral margin, which continues in a regulur descending, shallow, convex curve nearly to the postventral or respiratory angle. Only 

near the posterior extren1ity is the ventral margin horizontal or faintly ascending; it swings in 

nn abrvpt retrorse curve into the posterior margin. Both the lowest and the hindmost points 

of the shell are therefore near the respiratory angle. The posterior margin of the shell is rctrorse 

in 11 shullowly convex arch which swings forward a little more rapidly as it approaches the hinge 

line. Tho posterior margin of tho shell, up to the hinge extremity, and the posterior two-thirds 

of tho ventral margip. are approxunatcly symmetric with reference to a line drawn from, the 

postivcntral extremity to the beak. The hinge line is slightly convex; its length behin.d the 

bonks is equnl to from one-half to three-fifths that of the posterior n1argin. The hinge line 

nnd tho ventral1nargin converge forward at an angle varying between 12° and 28°, generally 

no11rly 2.5°. The shells display a rounded postumbonal ridge on which the point of greatest 

depth is situated between one-third ·and one-half the distance from beak to postventral extremity. This is posterior to the n1iddle. The postumbonal slope is steep and flat, becoming slightly 

concave in profile ncar tho hinge line. ·Anterior to the beaks the shell is depressed convex. The 

umbones are depressed down to the hinge line. The depth of the valve with both valves in 

conjunction 11ppears to have been equal to··only one-third the distance from beak to respiratory 

angle, and in internnl molds was only two-sevenths this distance or less. 

The anterior muscular scar is large and impressed with moderate distinctness. It is situated 

on the floor of the valve on a line between the beak and· forward extremity of the shell, and is 

equnl in length to one-third this distance or a trifle more. It is variably oval, ovate, or semicircular, the posterior portion ri:wre deeply impressed into the shell than the anterior. The 

posterior muscular scar is not distinctly impressed on any of the specimens and must have been 

extre1nely faint. The pallial line begins at the anteroventral margin of the anterior muscular 

scar, so thnt nearly all the muscular scar is behind the mantle attachment. The pallial line 

extends pnrnllel with the ventral margin, 2 or 3 millimeters distant from it, nnd is. strongly 

impressed for about one-hnlf to two-thirds the length of the ventral margin, beyond which 

it grndunlly weakens posteriorly and becomes invisible. The portion of the shell below the 

pnllial line is conspicuous on· internal casts and appears to have been thickened and convex 

on the interior. 

No trnce of posterior lateral teeth have been seen in Anodontopsis·maccoyiana sp. nov., unless 

a very faint incision on the internal mold of the left valve and a similar faint n1ark on the internal 

n1old of the right vnlve 1nay be so regarded. This faint line beco1nes gradually fainter posteriorly, diverges somewhnt fron1 the hinge line, and is not distinct (if discernible at all) beyond 

half tho length of the dorsal margin, where it is 2 or 3 millimeters below the dorsal edge, and produces a more or less definable flat strip at the dorsal edge. This line may possibly indicate a 

hinge platforn1 or posterior tooth, but more probably it represents either the insertion of an 

intcr.nul ( ?) ligan1ent or the dorsal insertion of the mantle, or both. None of the specimens from 

the locality 2 miles west of Presque Isle Stream arc well enough preserved to show cardinal 

teeth if they had been developed. A single internal mold of a left valve from Presque Isle Stream 

showing 11n interesting type of cardinal dentition may prove not to belong to the present species. 

This specimen indicates tho presence of two or three radial very faint cardinal teeth in the left 

valve and one less in the right; these teeth and their corresponding sockets are very weak in 

front nncl increase in strength going backward, so that the hindmost tooth of the left valve is 

fnirly well developed. The cnrdinal teeth arc directed radially toward a point a little above 

the postventral extremity. ·Thi8 specimen may be a young individual of Modiomorpha aroostoolci rather than an ndult ·of Anodontopsis maccoyiana. 

Ligan1cnt unknown, possibly linear, or, judging from the faint line, internal. Shell Inodoratoly thick; s1nooth (devoid of growth lines) on the interior; structure not examined. 
238 FAUNA OF THE CHAPMAN SANDSTONE OF MAINE. 

The surface of the· shell is covered with concentric raised lines and impressed strire of growth, 

which are best developed posteriorly just below the hinge line and anteriorly near the front 

margin. About 20 of these strire were counted in a space of 4 millimeters near the postdorsal 

extremity of one specimen. On some well-preserved shells these strire are covered by still finer 

extremely minute concentric striation~ that are visible only under a·magnifying glass. 

The smallest specimen observed was 9.75 millin1eters long and 9 millimeters high. Three 

of the largest specimens were 30 millimeters long and 24 to 28 n1illimeters high. 

The distinguishing features of this fossil are the cyrtodontiform outline, with large, welldeveloped anterior end; posterior end expanding in height; beaks at about the anterior third, 

not projecting above the hinge line; absence of lunule or concavity in front of the beaks; relatively depressed convexity compared with Cyrtodontidre; point of maximum depth on the 

rounded postumbonal ridge; fairly large and distinctly impressed anteripr muscular scar situated near the anterior margin; usually. nondiscernible posterior scar; pallial line strongly 

impressed in the forward half, with the shell thickened on the interior below the pallial line; 

absence of posterior teeth; moderately thick shell; and concentric lines best developed near the 

posterior hinge line and near the anterior n1argin. 

Locality: Chapman sandstone, 2 miles west of Presque Isle Stream (locality 1099 J), 

Aroostook County, Maine, where the species appears to be abundant. A single specimen was 

found on Presque Isle Stream at the end of the Tweedy road (locality 1099 L). 

U. S. National Museum, catalogue Nos. 59822, 59823. 

Oomparisons.-This shell, as has been stated, n1ay easily be confused with Anodontopsis 

angu.stifrons McCoy, from the Upper Ludlow-Downtonian grits of Kendal, Westmoreland. The 

Chapman shell, however, is rather higher posteriorly, and has the posterior margin a trifle less 

retrorse than in the English shell. The ornamentation is rather finer and sharp~r in the Chapman 

specimens than in the sculpture casts of. the British fossils, but this may possibly be due to a 

difference in conditions of preservation rather than to any original difference. McCoy, ill 

describing the anterior of Anodontopsis angustifrons, stated that "The posterior lateral tooth or 

plate extends almost to the end of the h1nge line and close to it." In the American shell this 

tooth is indefinite beyond the midlength of the hinge. 

Clarke 1 has described a large Anodontopsis ( ~) from the Chapman sandstone of Edmunds 

Hill under the name Modiomorpha vulcanalis. Anodontopsis maccoyiana hardly attains half 

the size of the gigantic Edmunds Hill species and shows some minor differences in details of 

outline. Clarke's shell may be congeneric with Anodontopsis maccoyia.na, but it is not a 

Modiomorpha. 

A. maccoyiana also resembles the so-called Oypricardella pohli Clarke, 2 from the Lower 

Coblenzian ·fauna of Rio Maecuru, Para, Brazil. The Brazilia1~ shell differs specifically from 

the Chapman fossils in being more narrowly cordate in outline, with a shorter anterior end, and 

in having slightly more prominent umbones and coarser and more distant surface markings. 

It is described as being "somewhat inflated." . If Oypricardclla pohli Clarke is not a member of 

the Cyrtodonta-Cypricardites group, it may be congeneric with Anodontopsis maccoyia.na. 

Superfamily TRIGONIACEA. 

Family TRIGONIID.tE Lamarck. 

Genus. SCHIZODUS King, 1844. 

ScHrzonus ~ PRUNUM sp. nov. 

Plate XX, figure 9. 

A sculpture cast of a right valve represents a bivalve of vertically elongate, plum-shaped 

outline, having an obscure schizodiform postumbonal ridge, more obscure than is indicated in 

the figure. Behind this ridge the surface descends in a sloping plane to the dorsal margin. In 

1 Clarke, J. M., New York State Mus. Bull. 107, p. 219, figs., 1907. 

2 Clarke, J. M., Mus. ·nac. Rio de Janeiro Arch., vol.)O, pl. 6, fig. 10, 1899 (author's English ed., p. 64, 1900). 
MOLLUSCA. 239 

front of the carination the surface is moderately and evenly convex. The umbone is broad, 

slightly in advance of the midd1e, faintly prosogyrate, and hardly protrudes above the dorsal 

edge. The oblique height, or dlistance from beak to respiratory angle, is one-fourth greater 

than the oblique length (measw·ed in a direction at right angles to the oblique height). The 

sm·face is n1arked by concentric lines of growth, which are faint on the posterior slope. 

Locality: Chapman sandstone, Edmunds Hill, Chapman Township, Aroostook County, 

Maine. 

OomzJarisons.-The vertical elongation of the shell would seem to suggest a relationship 

with similarly elongate shells for whlch Miller 1 has p:t;oposed the generic name Angellum, but 

the contour of the surface of the Chapman shell precludes any close affiliation with the peculiar 

Angellum, the genotype of whieh is Angellum cuneat1.tm :Miller, from the upper part of the 

Cincinnatian series at Richmond, Ind. In Angellum the surface of the shells is uniformly and 

deeply inflated; there appears to be an anterior byssus and a posterior alation; the umbones 

ru·e elevated, arch over the dorsal line, and are pronouncedly prosogyrate. 

The Chapmmi shell conforms more nearly with the peculiar elongate bivalve described ai1d 

figured by Kayser as Modiomorpha? subrectangularis, 2 from the German basal Devonian or 

Tau.nus quartzite at Katzenloch, near Idar. The German species is less oblique and has a less 

well-defined carination posteriorly than the Chapman shell and is of slightly different outline, 

but the two forms are evidently closely related and probably belong to the smne genus. 

Kayser figures two nearly equal muscular scars and describes a probable small tooth under 

the beak. These characters, with the outline, would seem to indicate that the genus is neither 

Modiomorpha nor Schizodus, but. more probably allied to Cypricardella, from which' the shells 

differ conspicuously in the vertical elongation. 

Cf. Scrrrzonus sp. indet. 

Plate XXIV, figure 8. 

A small schizodiform shell fr01n the Chapman sandstone of Edmunds Hill is represented by 

a sculpture cast of a right valve 23 millimeters high and 2~ millimeters long. The. umbones 

ru·e at or in advance of the anterior third, are depressed to the hinge line, and are directed 

vertically or faintly prosogyrate. The forward end of the shell is high but short; the ventral 

margin is gently curved; the anterior and basal margins from beak to respiratory angle form a 

rather regular arch slightly deeper than a semicircle. The posterior margin is convex, retrorse, 

and equal in length to the hinge line, which descends backward from the beaks. The umbonal 

carination is very faint. The depth of the single valve is about one-fourth itsheight. 

Locality: Chapman sandstone, west side of Edmunds I-Iill (locality 1099 M), Chapman· 

Township, Aroostook County, :Maine. 

U. S. National Musemn, catalogue No. 59824. 

Order TELEODESM.ACEA. 

Superfamily ASTARTACEA. 

Family ASTARTID.fE D'Orbigny. 

Genus CYPRICA:RDELLA Hall (MICRODON Conrad), 1856-1858. 

The genus Microdon was founded by Conrad in 1842 for the well-known ]{icrodon (Oypricardella) bellastriata 3 Conrad, fro:m the Hamilton formation of New York. Conrad's original 

diagnosis 4 of the genus is as follows: · 

Shell bivalve, equivalve; hlnge with a slender oblique tooth in the left valve. The genera of many of the bivalves 

of the Pa.leozoic rocks are very little known. Casts of the hinge and teeth are rare, and the external form, though it 

1 ?lUI lor, S. A., Description of a new genus and eleven new species of fossils, with remarks upon others well known from tho Cincinnati group: 

Cincinnati Soc. Nat. Hist. Jour., vol. 1, p. 105, pl. :3, fig. 11, 1878; in North American geology and paleontology, p. 462, fig. 774, 1889. 

2 Kayser, Emanuel, Ueber oinige neue Zweisehaler des rheinischen Taunusquarzits: K. preuss. geol. Landesanstalt Jahrb. 1884, p. 18, pl. 2, 

fig. 3, 1885. 

s '1'110 spelUng of tho spocHic name bellastriata a.s here given is according to the author's usage. in the following pages the correct form bellistriata wm be used. 

• Conmd, T. A., Observations on the Silurian ltnd Devonian systems of the United States, with descriptions of new organic remains: Acad. 

Nat. Sci. Philudolphia Jour., vol. 8, p. 247, pl. 13, fig. 12 (shows only external form of Microdon bellastriata), 1842 (read Jan. 18, 1842): 
240 FAUNA OF THE CHAPMAN SANDSTONE OF MAINE. 

sometimes may afford a clue to the generic relations of a bivalve, is often useless for that purpose. In the present 

instance a provisional generic name is given, because I can not refe~ the shell to any published genus; but I must 

ac~nowledge that the casts of the hinge and teeth which I have yet seen are not very clear or satisfactory. · 

In 1851 McCoy 1 proposed the generic name Anodontopsis for certain English fossils. His 

description of Anodontopsis follows: · 

Synonym, Microdon? Conrad (not Agassiz nor Meigen). 

General character: Equivalve, inequilateral, compressed, general form rotundato-quadrate .or subtrigoral; posterior side wide; round or obliquely subtnmcate, anterior end slightly contracted in front of the beak; beaks small, 

prominent, nearer to the anterior than to the posterior e1.1d; hinge line shorter than the shell, with a posterior long, 

slender lateral tooth, or cartilage plate, extending just below it (double in the right valve), and another similar but 

shorter one in front of the beaks; anterior and posterior muscular impressions simple, ovate, the latter longer and 

stronger than the anterior; occasionally a slight clavicular ridge extends from in front of the beak behind the anterior 

adductQr impression, leaving a furrow in the cast; pallial impression entire (occasionally one small cardinal tooth beneath 

the beak); surface smooth or concentrically lined. 

Except in their small size and marine habits these little fossils resemble the recent Anodons, from which there 

being but two simple adductor impressions separates them: They differ from Modiolopsis (or Cypricardites) in their 

rotundato-quadrate compressed form and the posterior adductor impression like the anterior one, and they have no 

trace of the byssiferous sinus so common in that group between the body of the shell and the anterior side; from 

Schizodus (Myaphoria), with which Prof. King seems to have blended them, they are distinguished by the long, 

slender posterior .cartiiage plate or lateral tooth, a little below the hinge line. Except in form they are identical 

with Clidophorus, and should be considered but as a subgenus thereof, distingt,Iished from those long narrow types by 

their broad, rounded or oblique axlike form, more prominent beaks, and less marked clavicuiar ridge. From the 

figure of Microdon bellistria[ta] (Conrad), I should have imagined it belonged to the present genus, but his description 

of the hinge renders it probable that this genus is different, and I accordingly give a description of my own clear types; 

besides which the name Microdon was applied long previously to ,a gen~s of fish and one of insects. 

McCoy included five heteromorphous species in his genus Anodontopsis. All are from the 

Upper Ludlow and Tilestone faunas of Britain. The genotype, Anodontopsis angustifrons 

McCoy, resembles Microdon or Cypricardella but differs in having the cardinal line ascending 

rather. strongly, giving the shell the outline of the Cyrtodonta-Cypricardites groups. The 

second species, Anodontopsis bulla McCoy, is a circular shell which would now be placed probably 

in the genus Paracyclas Hall, or possibly in Cycloconcha Miller. The third species, Anodontopsis lcevis or Pullastra lcevis Sowerby,2 has apparently the ·expression of a typical "Microdon." 

The last two species, Anodontopsis quadratus McCoy and Anodontopsis securiformis McCoy, ·are 

schizodiform shells, and A. securi.formis has been made the type of Salter's genus Pseudaxinus.3 

In liall's original account4 of the new well-known dwarfed fauna in the so-called "subCarboniferous" (Mississippian) limestones about Spergen Hill, Ind. (now known as the Spergen 

limestone), he described a new genus of littl~ lamellibranchs tinder the nan1e Cypricardella, as 

follows: 

Shell ovate or subelliptical and subquadrate (subequilateral), closed. Surface concentrically striated; hinge of 

right valve having two cardinal teeth; the anterior tooth directly beneath the beaks, somewhat strong, triangular, 

slightly directed backward [nearly vertical]; posterior tooth more slender and turned obliquely backward, very 

nearly horizontal, leaving a triangular pit which is probably occupied by a tooth in the other valve. Anterior cardinal margin with a long, narrow groove, apparently for the reception of a slender projection of the other valve; posterior side beveled from above, edge thin, ligament external, occupying a; deep cavity; muscular impressions distinct, 

shallow, equal in Size or very nearly equal; pallial impression simple. 

Of the four species of Cypricardella here described by Hall,· 0. subelliptica,. 0. nucleata, 

0. oblonga, and 0. plicata, only the first three belong to Hall's genus.· Figures of Oypricardella 

nucleata and of the genotype, Oypricardella subelliptica, showing the hinge structure of the 

latter, were given in the "Geology of Iowa" in 1858.5 No reference was made by Hall to 

Microdon Conrad, and it was riot until 25 years later that Whitfield announced the identity 

of Cypricardella and ~1icrodon. 

1 Annals and Mag. Nat. Hist., 2d ser., vol. 7, pp. 53-54, 1851. Sec also Sedgwick, Adam, and McCoy, Frederick, British Paleozoic rocks and 

fossils, p. 270, 1852. 

2 Murchison, R. I., 'l'ho Silurian system, pl. 3, fig. la, 1830. 

3 Salter, J. W., Note on the fossils from the Budleigh-Salterton pebble bed: Geol. Soc. London Quart. Jour., vol. 20, p. 208, 1864. 

4 Hall, James, Description ·or new species of fossils from the Carboniferous limestones of Indiana and Illinois: Albany Inst. Trans., vol. 4, p. 17 

read Nov. 27, i856. 

· 5 Iowa Geo.l. Survey, vol. I, pt. 2, pp. 663-664, pl. 23, figs. IG-12, 1858. 
MOLLUSCA. 241 ~ 

In 1869-70 Hal1 1 used the name Microdon a~d described, besides Conrad's lJ{. bellistriata, 

four new species-three (11!. g1"egaria, M. tenuistriata, M. complanatus) from the Hamilton, 

Portage (Ithaca shn1e n1ember), and Chemung-formations of New York and one (M. reservatus) 

from the Mississippian of Ohio. 

In 1873 I-IaH 2 figured the generic featlires of "Microdon," showing a left valve of lJf.. 

tenuistriata I-Iall with the teeth and muscular markings, and a righ~ valve of .M. bellistriata 

exhibiting si1nilar features. These are the first illustrations of the generic characters of the 

Devonian shells of the genus Mierodon of Conrad. · 

· In 1877 Miller 3 'called attention to the fact that Microdon was preoccupied by Agassiz 

(1833) for a genus of fish and also by Mergen (1803) for a genus of insects. Miller rejected the 

name Microdon Conrad but did not propose any new name. In an appendix to Miller's work 

I-:Iall 4 proposed a few new nan1es for some that were preoccupied, among these being Eodon 

I-Iall, 1877, proposed for Microdon Conrad. 

In 1881 Oehlert 5 described and figured a 'little "Microdon" from the Lower Devonian 

limestones of Nehou, Le Manche, Normandy, which he incorrectly identified with M. bellistriata 

Conrad. Oehlert noticed the preoccupancy of Microdon Conrad, as indicated by Miller in 1877, 

but apparently overlooked the .appendL"< to Miller's work, in which Hail had proposed the 

nrune Eodon, for he suggested the new generic name Microdonella for Conrad's genus. In view 

of the existence of Eodon· Hall,. 1877, Microdonella Oehlert, 1881, can have no value. 

In 1882, in the revised deseriptions of the faunas of the Spergen limestone, Whitfield 6 

introduced some "observations of the genera Microdon Conrad and Cypricardella and Eodon· 

1-Iall." I-Ie figtu·ed 7 and redescribed the original Cypricardellas from Spergen Hill and also 

redescribed the genus and showed it to be identical with Microdon Conrad except that the 

Carboniferous Cypricardellas are 1nuch more gibbous than the compressed Hamilton Microdons, 

owing, Whitfield believed, to crushing of the :Microdons in the shales, whereas the Carboniferous 

forn1s ru·e preserved uncompressed in limestones. · 

That the difference in convexity between the ventricose Carboniferous Cypricardellas and· 

the c01npressed Devonian Microd6ns is not structural but may be explainable, as suggested by 

Whitfield, is indicated by the fact that Oehlert's Microdonella bellistriata as preserved in the 

Lower ])evonian li1nestones of Normandy is very gibbous, ~hereas in the Ithaca member 

Microdon tenuistriata Hallru1d 111'. gregaria Hall occur in various stages of compression-the 

least-con1pressed forms being alm.ost as strongly convex as the Carboniferous Cypricardellas, 

though they are appru·ently of the san1e species as the nearly flat specimens occurring in the 

surrounding arenaceous shales. 

While Whitfield ·was working on the Spergen fauna I-Iall was preparing a report on the 

san1e fauna, which appeared in 1883.8 In this report Ilall redescribed the species of Cypricardella, as well as the genus itaelf, and inserted Whitfield's plates of illus.trations. l-Ie .noted the 

si1nilarity of the Spergen Cypricardellas to Microdon (whether following Whitfield or independently is not indicated) but regarded the knowledge of the hinge of Microdon as too meager to 

warrant uniting the two genera. ~ 

Tliis opinion· was still held by Hall in 1883, 9 when he figured 11fic1'odon ( 11ficrodonella) 

(Eodon) gregffrius I-Iall, 11!. (11.£.) (.E.) bellist1'iatus Conrad, lJf. (lJf.) (E.) tenuistriatus Hall, and 

M. (11.1.) (E.) complanatus, from the I-Iamilton of New York; },.f. (:ilf.) (E.) gregarius I-Iall and 

},f. (J.f..) (E.) bellistriatus Conrad, from the Chemung; and ~f. (M.) (E.) reservatus I-Iall, from the ---------·- --- -·· ·• 

1 Prollmluary notice of the lamellibrauchiato shells of the Upper Helderberg, Hamilton, and Chemung groups, pt. ·2, pp. 30-33, 1870. 

2 Hall, Now York State Mus. of Nat. llist. 'l'wenty-third A1m. Rept., pl. 14, figs. 7 o.nd 8, 1873. 

u :Mlllor, S. A., North American Paleozoic fossils, Jist ed., p. 194, 1877. 

4 Idom, pp. 243-245. · 

G Oohlort, D.P., Documents pour servir it l'etud<• des faunes devonienn~s dans !'ouest de Ia France: Soc. geol. F ranee M:em., 3d ser., vol. 2, 

pp. 20, 27, pl. 4, figs. 4-4b, 1881. 

o Whitfield, H. P., On tho fatulll of the Lower Carboniferous limestone of Spergeu Hill, Indiana, with a revision of the descriptions ofits fossil.s 

hitherto published and illustrations or tho species from the original types: Am. Mus. Nat. Hist. Bull., vol. 1, No.3, pp. 63 et seq., pl. 7, Oct. 20, 1882. 7 Jdom, pl. 23. 

e Indiana Dept. Geology and Nat. Hist. 'l'welfth Ann. Hept., pp. 319-375, 1883. 

s Paleontology of New York, vol. 5, pt. 1, prelimluary edition of plates, pls. 73, 74, 1883. 

50245°-NO. 89-16--16 
242 FAUNA OF THE CHAPMAN SANDSTONE OF MAINE. 

Mississippian of Ohio .. As he made no m~ntion of Cypricardella, it is quite apparent that he 

still considered the Devonian large compressed Microdons distinct from the Carboniferous small 

gibbous Cypricardellas. 

Hall abandoned this opinion two years later, 1 however, and united Microdon Conrad 

(Eodon Hall, 1877; Microdonella Oehlert, 1881), and Cypricardella Hall, 1856, describing the 

New York Devonian species and the Mississippian species already cited and, in addition, a 

new species, Microdon (Oypricardella) major I-Iall, from the "Corniferous" of Ohio, the first 

species occurring in America below the Hamilton. 

After Whitfield's work on the Spe1;gen fauna De Koninck, 2 in his monograph on the 

lamellibranchs of the Belgian Carboniferous limestones, recognized Microdon Conrad as a synonym of Cypricardella. He states, apparently through inadvertence, that the name Cypricardelia had been proposed by Hall to replace Microdon Conrad because the latter name had been 

preoccupied. Such, of course, was not the real state of affairs. De Koninck described 15 

species of Cypricardella from etages II and III (Visean), and showed the hinge structure of 

several of them. · 

As a result of the work of Whitfield, Hall, and De Koninck, Microdon has been abandoned 

and Cypricardella, originally proposed for Carboniferous shells, has come into general use for 

the Devonian shells also. In 1895 appeared Beushausen's work on the lamellibranchs of. the 

Rhenish Lower Devonian, 3 in which he described nine speciea of typical Micro don Conrad as 

Cypricardella and elucidated the hinge structure of several of these species. 

The fine illustrations of Hall and of Beushausen show tliat the Devonian Microdons are 

not distinguishable by any definite characters from Cypricardella, although the facts that the 

Devonian Microdon is large and compressed, while the Carboniferous Cypricardella is ventricose 

and smaller, as already explained, and that Microdon seems to be thinner shelled, suggest a 

doubt as to their positive identity. The doubt is augmented by the fact that the Carboniferous 

species, instead of being larger thai! t~e more primitive Devonian Microdons, are in both Europe 

and America invariably smaller.· Moreover, continuing into the Pennsylvanian and Permian, 

the small Cypricar,dellas lose the umbonal carination and become evenly rounded and trigonal, 

as in Astarte, and the teeth become stronger, also as in Astarte. Cypricardella is evidently a 

forerunner of Astarte and tow~rd the close of the Paleozoic becomes hardly distinguishable 

from it; but "Microdon" seems not at all related to this group. However, the positive characters of the Devonian Microdon and the typical Carboniferous Cypricardella do not indicate 

any substantial.generic differences. 

On the assumption, therefore, that the Devonian forms of the type of Conrad's Microdon 

and the Carboniferous forms called Cypricardella by Hall are generically the same the genus 

may be described as follows: 

Bivalve, equivalve, closed throughout. 

Outline in general rotundo-quadrate, with the length greater than the height but less 

than twice the height. Umbones depressed, not extending appreciably beyond the cardinal 

line, prosogyrate, situated anterior to the nl:iddle and separated from the narrower rounded 

anterior end by a concave lunule. The cardinal line is distinct; nearly horizontal, sometin1es 

declining, rarely slightly ascending; shorter than the length of the shell; slightly convex or 

nearly straight. The postcardinal extremity is rounded subangular. The posterior 1nargin is 

slightly retrorse or nearly vertical; rounded, convex. The ventral margin is always rounded, 

convex, and without any insinuation or flattening; it curves into the anterior end, which is 

always dis.tinct, narrower than the body, and separated by a concave lunule from the beaks. 

The shells are compressed, bic~nvex, but when occurring in limestone are generally n1ore deeply 

convex. A low and persistent though undefined umbonal ridge is more or less conspicuous, 

though never angular; it is also never sigmoid nor concave, being generally nearly straight or 

a little arched convex; it is absent in a few late Paleozoic species and in some individuals of 

1 Paleontology of New York, val. 5, pt. 1, 1885. 

2 De Koninck, L. G., Faune du calcaire carbonifere de la Belgique, val. 3, pt. 5, pp. 91-98, 1885. 

a Die Lamellibranchiaten des rheinischen Devon: K. preuss. geol. Landesanstalt Abh., new ser., val. 17, pp. 134-146, 1895. 
MOLLUSCA. 243 

I 

earlier species. The surface is depressed convex both below the umbones and posterior to the 

cariuation; there is no insinuation or flattening comparable wit4 that in the n1odiomorphoids. 

'!''he lunule 1 is occupied by a pronom1ced lunette. Posteriorly there is a long, deep, but 

narrow escutcheon, the shape of which almost 1nakes the ligament appear, in isolated valves, 

to be internal. 

I-linge plate very thin, especially in the early species. In the right valve, just under the 

tip of the beak and at the end of the lunette, there is a small, short, narrow radial fold or tooth, 

smnetimcs hardly discernible. This tooth is nearly but not quite vertical, inclining a trifle 

posteriorly frmn the beak. Just back of it is a much larger triangular socket for the reception 

of the large cardinal tooth of the left valve; this triangular socket, the direction of which is 

nearly horizontal, subtends at the tip an angle not exceeding 45° and generally much less . 

. Above the socket, in the right valve, there is a long, narrow cardinal tooth, which is approxiInately horizontal or very slightJly ascending, and which, though long in proportion to its width, 

extends but slightly beyond tho beak. 2 There are no posterior laterals. In the left valve the 

most conspicuous feature is the large, triangular, nearly horizontal tooth, fitting into the triangular socket of the right valve. Just in front of it is a smaTI depression for the reception of 

the Jni.nute anterior tooth of the right valve, and just back of It :s a slit for the reception of the 

second or longer narrow tooth of the right valve. The dental structure n1ay be summarized 

as two narrow radial folds or c~udinal teeth in the right valve inclosing a triangular cavity for 

the reception of the single large triangular cardinal of the left valve, which is preceded and 

followed by a tninute cavity for the reception of the teeth of the right. 

The adductor n1uscular scars are equal or nearly equal in size, shallow, and very feebly 

impressed; pedal scars nondisce:rnible. The posterior scar is very near the postcardinal extrmnity; the anterior scar is at a dist.ance from the beak and begins at the anterior end of the lunule. 

Pallial line sin1ple, entire. Shell structure m1known. 

Surface sn1ooth or with concentric lines of growth commonly bellistriate, but not concentrically plicose or wrinkled, and without radial markings. Size sn1all to medium. The largest 

species (C. major I-Iall) is 72 millimeters long and 48 millimeters high, but com1nonly the size 

does not exceed half these· dhnensions, and in the Carboniferous forms the shells are much smaller. 

The geologic range is from the Upper Ludlow (late Silurian) through the Permian. Most 

abundant in the ·siegen and Lower Coblenzian graywackes in the Rhenish Lower Devonian; 

in the l\1eso-Devonian fiamilton and Portage (Ithaca shale number) formatim'ls of New York; 

in the Mississippian Spergen liinestone, and in the Visean. The later forms tend toward Astarte 

by the strengthening of the tooth and the rounding of the postcardinal extremity and cardinal 

line, and by the consequent loss of their quadrate outline, with assumption. of the trigonal or 

astarti:fonn outline. 

The relation of Cypricardella (Microdon Conrad) Hall, 1856-1858, to Anodontopsis McCoy, 

1851, is difficult to determine because illustrations of the hinge structure of Anodontopsis are 

lacking. The most striking fea,ture in Anodontopsis is the supposed occurrence of a posterior 

long, slender lateral tooth just below the hinge, apparently double in the right valve, whereas 

in Microdon no laterals exist. McCoy stated definitely that these supposed posterior laterals 

1night be only an externalligan1ent groove or cartilage plate (escutcheon), and, as some figures 

of the Microdons 3 show si1nilar appearances, it seems probable that, as McCoy believed, the 

supposed posterior laterals are indications of a deep, long escutcheon, as in :Microdon. Of the 

five species of Anodontopsis Mc.Coy, all except Anodontopsis angustrifrons McCoy, the genotype, 

may he elimi.n:ated frmn consideration. In this shell, as has been stated, the cardinal line 

-- --- ----------------------------~--------------------------------------------- 1 ~l'he tonus "lunule" and "lunette," though often used indiscriminately, indicate distinct featur·es. The lunule is the general concavity of 

tho dorsal margin immediately in front of the beaks in most Iamellibranchs; the term "lunette" is applied to an excavation in the lunule for the 

reception of tho forward ligamon t. 

~ Whoolton Hind (llrit.ish Carboniferous Lamellibranchiata, vol. 1, p. 347, London Paleontogr. Soc., 1899) regards this hindmost tooth as 

a posterior lateral, and honce·describes Cypricarclella as having posterior laterals. 8 Soo especially Krantz, A., Ueber ein nones bei Menzenberg aufgeschlossenes Petrefakten-Lager in den Devonischen Schichten: Naturh. Verein 

preuss. Uholnliinde Vcrh., vol. 14, p. Hi2, pl. 11, fig. 1 ( Tellina bicostula Krantz), 1857. This is a Microdon (Cypricardella), as was recognized by 

Bousbo.uscn (op. cit., pp. 137-138); sco o.lso Beushausen's figures of Cypricardella elongata Beushausen and C. unioniformis (Sand berger) (idem, pt. 

11, figs. 14b, 19b). 'l'hose figures illustrnto very well a feature that might, though occurring in typical MJcrodon, be easily mistaken for the appearance of two posterior laterals in the right valve. 
244 FAUNA OF THE CHAPMAN SANDSTONE OF MAINE, 

ascends posteriorly and thus gives the shell the superficial aspect of ·a compressed Cyrtodonta 

or Cypricardites, or of a modiolopsoid; but the species is readily distinguished from the modiolopsoids by its convexly rounded, noninsinuated basal margin and by its distinct rounded 

narrow anterior end, separated by a lunule from the beak; it also has an umbonal undefined 

ridge. In these three respects A. angust~frons very closely resembles Cypricardella (Microdon)_, 

differing apparently only in having the cardinal line somewhat more strongly ascending. Among 

the typical Cypricardellas, however, some forms have a markedly ascending cardinal line; 

among these are Microdon ( Oypricardella) major Hall, 1 from limestones of the age of the ''Corniferous" at Delaware, Ohio, and },f. ( 0.) complanata Hall,2 from .the highe~ arenaceous beds 

of the I-Iamilton of eastern New York. Moreover, the great variability in the direction of the 

cardinal line in the same species of Microdon (Cypricardella)-for instance, in M. ( 0.) bellistriata Conrad, in which the cardinal line is descending in some species 3 and slightly ascending 

in others ~suggests that ·McCoy's Anodontopsis angustifrons as represented in his plate I, K, 

figure .14, is a cypricardelloid shell. If by its internal features this species can be shown to be 

congeneric with the coterie of shells associated about Microdon bellistriata Conrad, then the 

name Anodontopsis McCoy will have precedence over Cypricardella I-Iall or any of the other 

known names used in substitution for the .preoccupied Microdon Conrad. Fron;t. present knowledge (or rather lack of knowledge of McCoy's type species, however, I can not definitely consider it congeneric with the Microdons; indeed, McCoy's description of Anodontopsis and A. 

angust~frons indicates that the posterior muscular impression is longer and stronger than the 

anterior, whereas in Cypricardella (Microdon) . the muscular scars are approximately equal in 

size and the posterior scar is weaker than the anterior. McCoy's statement may be taken with 

some reservation, for in dimyarian shells, such as the Anodontopsis forms seem .to be, to have 

the posterior scar stronger than the anterior would indeed bg anomalous. Again, McCoy states 

tha,t in Anodontopsis there is "occasionally one small cardinal tooth beneath the beak." In 

Microdon (Cypricardella) 5 there are two cardinal teeth in the right valve and on~ in the left. 

I feel justified, therefore, in stating that knowledge of the structure of Anodontopsis McCoy 

and the genotype A. angustifrons McCoy is insufficient to warrant uniting, these forms with 

~Iicrodon Conrad and substituting McCoy's name for the preoccupied Microdon, and that, so 

far as I am acquainted with McCoy's fossils through his published descriptions, his shell is not 

congeneric with ·Microdon Conrad (Cypric~rdella). The name Cypricardel1a will, therefore, 

be retained. 

CYPRICARDELLA BELLATULA ·sp. nov. 

Plate XXI, fignre 1. 

An interesting quadrate, complanate, minute Cypricardella is represented by several specimens from Presque Isle Stream (l~cality 1099 A), where it appears to be fairly common. 

Form subrhomboidal; length about one and three-eighths times the height, the ratio of 

length and height varying from 4:3 to 3:2; greatest length near the midheight; greatest height 

between the anterior and posterior third. The umbones are depressed, reaching the cardinal 

line but not extending beyond, incurved, directed strongly forward. The beaks are generally 

situated at the anterior fourth (varying between the anterior .fifth a.nd two-sevenths in different· 

specimens). The cardinal line is horizontal, perceptibly arched, length about seven-eighths 

the height of the shell. The cardinal extremity is obtusely subangular, distinct, rarely broadly 

· rounded, and is situated at or near the posterior tenth of the length of the shell. The posterior 

nutrgin forms an evenly rounded convex curve, slightly retrorse above and curving forward in 

the lower part, so that the most posterior point is near the midheight. The ventral margin is 

convex throughout; the postventral ·angle is obtusely rounded; the ventral margin for the 

posterior two-thirds of its length is gently arcuate, almost horizontal, but curves strongly 

t Paleontology of New York, vol. 5, ·pt.' 1, p. 307, pl. 42, fig. 21, 1885. 

2 Idem, p. 311, pl. 42, fig. 22; pl. 74, fig. 16. 

a Idem, pl. 73, figs. 10, 13; pl. 74, fig. 8. 

4 Idem, pl. 73, figs. 15, 19. Compare the variability of this feature in M. (C.) gregaria and .M. (C.) tenuistriata as figured by Hall. 

~The figures of the dentition of Microdon given by Hall are imperfect and do not indicate the conditions normally found in these shells; in 

this respect Beushausen's figures and descriptions are much more satisfactory. · 
MOLLUSCA. 245 

forward and upward into the anterior end. The extreme lowest point is apparently just in 

front. of tho midlength. The anterior end is prominent and rounded.; it extends three-fourths 

the height of the shell and· one-fourth the length, and is separated from the umbo by a short, 

well-marked lunule. Tho most anterior point is near or slightly above the midheight. The 

shells are compressed convex throughout and are marked by a conspicuous though undefined 

umbonal ridge, which is pronouiJced for· two-thirds of the length fron1 the umbo to the postventrnl angle and is less developed below; it is directed in a very slightly convex arch extending 

in a generitl direction of approxinaately 45° from the vertical. The surface is depressed convex, 

almost flat, from the ridge forward to below the beaks, and is more convex anteriorly. The 

greatest depth of the valve is a short distance below and back of the beak, on the umbon~l 

ridge,()at one-third the height below the cardinal line and just back of the midlength; the line 

from this point to the beak makes an angle of 40° or less with the length of the shell. The 

depth is about one-fifth or one-si.xth the height. Shell structure unknown. Internal and 

external 1nolds are generally rather glossy. A short distance below the cardinal line and 

parallel to it is a long, faintly unpressed line, usually found in Microdon (Cypricardella), indicating and resembling the inner edge of the escutcheon. Teeth unknown. An oval anterior 

adductor scar of 1nedium size is v-ery faintly impressed. It is separated by its length from the 

beak. No pedal or posterior muscular scars are discernible, except that there is a faint indi-· 

cation of an ovnl posterior scar, hardly distinguishable, at the cardinal extremity; it is apparently only very slightly if at all larger than the anterior scar. The mark is too obscure to 

consider it as definitely indicating a muscular scar. · 

Internal and external molds are nearly smooth but are marked by obsolescent, very fine 

lines of growth. In the single external mold observed, there are about three some-what stronger 

lines of growth or varices in the older half of the sheil. 

The n.verage-sized specilnens are about 1.5 millimeters thick (in single valves). The 

smallest speciJnen was 7.5 ·millin1eters high and about 10 millimeters long; the -largest 8.66 

milli1neters high and 13 millilnete:rs long. · 

This is the oldest known typical Microdon,· with the possible exception of Pullastra lrevis 

Sowerby, fron1 the Tilestone fauna,, which has been regarded as a Microdon (Cypricardella) on 

account of its outline, depressed convexity, umbonal ridge, and general expression. Sowerby's 

form 1nay, however, be a shell with slightly concave or insinuated ventral margin; if so it may 

prov-e to be Modiomorpha rather than Cypricardella. The small si~e of the Chapman shell is 

interesting in connection with its nge. Besides being the smallest Cypricardella known belo~ 

the Carboniferous, this species is eharacterized by its quadrate outline, with length 1 i times. 

the height; short, horizontal, arched hinge line equal in length to only sev.en-eighths the height. 

of the shell; strongly arched posterior 1nargin with posterior extremity at the midheight; 

v-entrnlinm·gin nearly horizontal for the posterior two-thirds of its length and arching upward 

nnd forward into the anterior end; well-developed. anterior end extending three-fourths the· 

height of the shell and one-fourth the length; depressed convexity; well-marked un1bonal ridge, 

d.ir~cted at approximately 45° to the length and height; nearly smooth surface with very faint. 

lines of growth and a few stronger varix-like lines in the earlier portion of the shell. 

Locnlity: Chapman sanq.stone, Presque Isle stream, at end of Tweedy road (locality 1099A),. 

Chaprr1a.ri Township, Aroostook County, Maine. · 

U.S. Nation~l Museum, catalogue No. 59825. . 

OompaTisons.-Oypricardella beUatula belongs to the group of quadrate smooth, compressed 

Cypricardellas including, in the Devonian faunas, Oypricardella gregaTia I-Iall,t Oypricardella. 

tenuistriata Kayser 2 (not Hall), Oypricardella ·cu1'ta Beushausen,S and 0. subovata Beushausen. 4 

Oy1Yricardella bellatula is, however, s.maller than any of the species indica,ted. 

• Hall, James, Pnloontology o~ New York, vol. 5, pt. 1, p. 309, pl. i3, figs. 1-6; pl. 74, figs. 1-4, 1885; 1\f.iddleand Upper Devonian. 

DKaysor, ]~manuel, Sur une faune du sommet de Ia serie rhCnane a Pepinstcr, Goe ct 1'ilfi' [Belgium]: Soc. geol. Belgique Annales, vol. 

23, p. 199, pl. 1, figs. 10, 11, 1896; Lower Devonian. 

sneushauscn, Louis, Dio Lamellibranchiaten des rheinischen Devon: K. preuss. geol. Landesansta~t Abh., new ser., vol. 17, p. H.J, pl. 12,. 

figs. 7-11, 1805; Lower Eo-Devonlan. · 

~Idem, p. 145, pl. 12, figs. 16, 17; Lower Eo-Devonlan. 
246 FAUNA OF THE CHAPMAN SANDSTONE OF MAINE. 

Fr01n the Belgian upper Eo-Devonian Cypricardella tenuistriata of Kayser (not Hall) the 

Chapman shell is distinguished by its slightly smaller size and by having the posterior margin 

more strongly rounded, with the most posterior point at the midheight, whereas in Kayser's 

form the most posterior point is at the base. 

Compared with C. curta Beushausen (the undistorted form)/ Cypricardella bellatula has 

the ventral margin more nearly horizontal in the posterior two-thirds of its length, and not 

bellied down in so strong an arch as in 0. curta. In Beushausen's species also the height is a 

trifle more nearly equal to the length than in C. bellatula. 

Compared with 0. subovata Beushausen, 0. bellatula has the posterior n1argin less truncated 

and more arched. In C. subovata the most posterior point is near the base instead of the middle, 

the ventral margin is n1ore strongly bellied down, and the ornamentation is more pronouncedly 

bellistriate. 

C. bellatula is easily distinguished from Cypricardella gregaria Hall by its proportionately 

higher anterior end. In C. gregaria, also, the posterior extremity is usually nearer the base 

than in C. bellatula, the ventral margin is commonly more strongly bellied down, and the shell 

is larger than ·a. bellatula and generally proportionately longer. Hall 2 represents a little 0. 

gregaria from the Ithaca shale member of the Portage formation at Cortland, N. Y., which is 

remarkably similar to the Chapman fossils, but is slightly larger and has the anterior end not 

so high. 

CYPRICARDELLA ROTUNDATA sp. nov. 

Plate XXI, figures 14, 15; Plate XI:X, figure 25. 

?1884. cf. young ('?) of Schizodus orbicularia. Walcott, U. S. Geol. Survey Mon. 8, p. 181, pl. 5, :fig. Sa (not fig. 8). 

Lower Devonian: Atrypa Peak, Eureka district, ~ev. 

An interesting cypricardelloid shell found at Edmunds Hill (locality 1099 M) is characterized by evenly though gently inflated, nondepressed convexity over tho body of the shell, 

absence of any conspicuous umbonal ridge, and subcircular outline. 

Length 24 millimeters, between one and one:-fourth and one and one-fifth tin;:tes the height 

(19.5 millimeters); greatest height at the midlength; greatest length below the middle and onethird or more of the height above the base. Umbones small, not extending above the cardinal 

line; prosogyrate; beaks at the anterior fourth. Cardinal line slightly convex, nearly horizontal or declining slightly; equal in length to two-thirds the height of the shell. Highest point 

of the shell opposite the midlength. Cardinal extremity distinct, obtu3ely subangular. Posterior margin retrorse, extending nearly straight for a distance equal in length to the length of the 

cardinal line and passing into the postventral angle. Most posterior point of the shell at this 

angle, one-fourth the height above the base. The ventral margin is strongly bellied down in a 

rather deep, evenly convex arch, so that the lowest point at the midlength is about one-fourth· 

the height of .the shell below the respiratory (postventral) angle. The ventral margin arches 

gradually but strongly upward into the evenly rounded anterior end, which includes one-fourth· 

the length of the shell and two-thirds or more of the height and which is separated fron;1 the 

umbo by a small, shallow lunule . 

. There is no conspicuous or discernible umbonal ridge,· but from the position where it 

ought to be the surface inclines posteriorly in a depressed-convex though rather steep slope to 

the cardinal line and posterior m.argin. An~eriorly the surface is ·e~enly though gently inflated 

convex, nowhere flattened, nor does the degree of convexity change appreciably up to the 

anterio:r: and ventral margins. The point of maximum depth of the single left valve known is 

a trifle above and in advance of the middle. The depth (3.5 millimeters.) is equal to 0.18 the 

height and about one-seventh the length. Hinge and muscular features unknown. 

The internal mold is smooth, devoid of any ornamentation, and very dull, not glos3y. 

Size: Length -24 millimeters, height 19.5 millirneters, depth of left valve (internal 1nold). 

3.5 millimeters. 

1 Bcushausen, Louis, Die Lamellibra.nchiaten des rheinischen Devon: K. preuss. geol. Landesanstalt Abh., new ser., vol. 17, p. 144, pl. 12, 

figs. 7, 8. 

2Hall, James, op. cit., 74, fig. 1. 
MOLLUSCA. 247 

The distinguishing features of the species are its fairly large size (it is much larger than 

the si1nilarly inflated Carboniferous species); inflated, noncomplanate convexity; indefinability 

of any u1nbonal ridge; very strongly bellied-down ventral margin, giving the shell a subcircular 

outline; length between 1! and lt tin1es the height; cardinal line horizontal or very slightly 

declining, and equal in length to two-thirds the height of the shell; and retrorse, nearly straight 

posterior 1nargin with lllOSt posterior point at the respiratory angle. . 

Locality: Chapn1an snndstone, west side of Edmunds Hill, Chapn1an Township, Aroostook 

County, :Maine. 

U.S. National Musmnn, catnlogue No. 59827. 

Oomparis<?ns.-ln the inconspicuousness of the umbonal ridge and in the rounded surface 

with strongly arched ventral n1argin, the Chapman fossil resembles the figures of Oypricardella 

hm·tii Clarke/ a species frmn the Lower Coblenzian fauna of Rio Maecuru, Para, Brazil. The 

Brn,zilian fossil is transversely 1nore elongated, not subcircular; the cardinal line is therefore 

proportionately 111uch longer, and the shell is larger. 0. rotundata may be easiiy distinguished 

from the Maecuru fossil by its more circular outline. 

'J:'he outline recalls the group of small Cypricardellas, including 0. curta Beushausen, 

0. g1·egaria I-Iall, 0. subovata Beushausen, and 0. bellatula sp. nov., but these shells are complanate and have a conspicuous umbonal ridge, whereas 0. rotundata is evenly convex and has 

no discernible tnnbonal ridge. · 

In the Lower Devonian of Atrypa Peak, in the Eureka district, Nev., occurs a Sinall 

shell which is regarded· by Walcott as possibly· the young of his species Schizodus orbicularis, 

frorn the Lower Devonian of Lone Mountain. From the figure alone this s1nall shell can not 

readily be distinguished from the· Chapman fossil, though. Walcott's shell seems to have 

the u1nbonal ridge slightly n1ore pronounced and the anterior mtd slightly shorter than in 

0. rotundata. 

In the Belgian Carboniferous o·ccur many Cypricardellas-particularly Oypricardella 

cantraineana (De Rycld10lt) 2 and 0. parallela (Phillips) ,

3 both from the Visean-which partnke 

of the evenly convex or inflnted character of the body of the shell, the inconspicuousness of the' 

un1bonal ridge, and nearly subcireular outline of 0. rotundata. The Belgian fossils referred to, 

if they really belong to Cypricardella, which is uncertain, are all n1uch s1naller shells, with 

un1bones situated farther forward and 1nore tumid, and with a less directly demarcated postunlhonal slope. 

0. rotundata occurs in a hard, coarse-grained sandstone, and its convexity might perhaps 

be attributed to its noncmnpression in the roc;k; ·but the shell called in this paper Cypricardella 

cf. 0. bicostula (Krantz) is a cmnplanate species and 9ccurs in the same locality, in a very similar 

kind of rock__:possibly in the same stratun1, though this is not known; so that ·the com planation of the one and the convexity of the other seem to represent anatomic and not accidental 

differences. 

CYPIUCARDELLA TRANSVERSA sp. nov. 

Plate XXI, figure 8. 

This nan1e is proposed for a cypricardelloid shell which resembles 0. rotundata in· the evenly 

inflated, noncmnplanate body, but which is distinguished from that species by the transversely 

more elongated outline .. 

Length (33 1nilli1neters) equal to one and one-half times the height (21.75 millimeters); 

greatest height at the n1idlength; greatest length one-third or two-fifth~? the height above. the 

base. U1nbones sn1all, depressed, not extending above the cardinal line, prosogyrate; beaks at 

the nnterior fifth. Cardinal line not preserved in the type and only specimen but apparently 

declining slightly, smnewhat arched, length about three-fourths the height of the shell. Cardint~l 

extrmnity obtusely rounded. Posterior margin retrorse, slightly arched, nearly_ strn.ight as 

1 Clurko, J. M., Tho Puloozoic faunas of Pam, Brazil, pt. 2, Devonian Mollusca: Mus. Nac. Rio de Janeiro Arch., vol. 10, pl. 7, figs. 1-3, 1899 

(uuthor's English eel., p. 63, 1000). 

s De Koninck, L. G., Fmme du culcairo carbonifere de Ia Belgique, vol. 3, pt. 5, p. 93, pl. 17, figs. 31-35, 1885. 

a ldom, p. OG, pl. 13, figs. 50-51. 
248 FAUNA OF THE CHAPMAN SANDSTONE 'OF MAINE. 

far as the respiratory angle for a dista~ce about equal to the ,length of the cardinal line. The 

most posterior point is at the respiratory angle, which, on account of the strong arching of the 

ventral margin, is one-fourth the height above the base. Ventral margin bellied down, its 

.posterior third making with the retrorse posterior margin a somewhat rounded right angle. 

The lowest point of the shell is at the midlength. The ventral margin sweeps with a broad curve 

into the rounded anterior end, which includes one-fifth th~ length of the shell and about twothirds the height. The forward extremity is at the midheight. The upper anterior 1nargin 

immediately in front of the beak makes an angle of about 125° with the cardinal line back of 

the beak. The umbonal ridge is broadly rounded, scarcely discernible. The post!3rior slope 

is very steep, rounded, depressed convex. Anterior to the region of the u1nbonal ridge the 

surface to the anterior and ventral margins is rounded convex, evenly inflated, noncomplanate. 

The point of greatest depth is at the midlength of the shell, slightly above the midheight. The 

depth is 5.2 millimeters, or about one-fourth the height and about a sixth the length. The line 

from the point of maximum depth to the beak 1nakes an angle of 45° with the height and length 

of the shell. Hinge features unlmown. Muscular markings not in1pressed. 

The specimen, an internal mold, or possibly sculpture cast, preserves traces of concentric, 

obsolescent lines or low, narrow undulations of growth, apparently very nearly as well developed 

on the posterior slope as oil the body of the shell. . 

Length 33 millimeters, height 21.75 millin1eters, depth 5.2 millimeters (single right valve). 

The. distinguishing features of the species are the arched (slightly declining~) cardinal line, 

equal in length to about three-fourths the height of the shell; the transverse outline with the 

length of the shell equal to one and one-half times the height; posterior margin retrorse; posterior extremity at the respiratory angle one-fourth the height above the base; basal margin 

bellied down in a strongly convex arch; anterior end including one-fifth the length of the shell; 

inflated, noncompianate convexity, with rounded umbonal ridge; depth (each valve) equal 

to one-fourth the height and situated at the midlength a trifle above the midheight; concentric 

striation obsolescent. 

Locality: Chapman sandstone, Edmunds Hill, Chapman Township, Aroostook County, 

Maine. 

U.S. National Museum, catalogue No. 59828. 

Oomparisons.-The fossil, especially in the lower half, bears a very strong resemblance to 

0. rotundata, from which the most important and almost the only distinction is the decidedly 

more transverse outline. The species is also v·ery closely related to Anodontopsis ventricosa 

Billings/ from the Gaspe limestone No. 8 of Indian Cove, Gaspe, Quebec; the two species correspond closely in size, outline, curvature,'and ornamentation, but in Billings's species the" height 

at the umbone~ [is] twelve lines; depth of both valves, ten lines," which would make the depth 

of both valves five-sixths the height; whereas in Oypricardella transversa the depth of both 

valves is hardly half the height. Anodontopsis ventricosa Billings is therefore a much more 

gibbous shell. The umbones as figured by Billings are also more gibbous and inflated than in 

0. transversa. 

CYPRICARDELLA cf. C. BICOSTULA (Krantz). 

Plate XXI, figure 9. 

cf.1857. Tellina bicostula. Krantz, Naturh .. Verein. preuss. Rheinland Verh., vol. 14, p. 162, pl. 11, fig. 1. 

Siegen graywacke: Menzenclorf, near Bonn, Germany. 

1885. Curtonotus grebei. Kayser, K. preuss. geol. Lanclesanstalt Jahrb., 1884, p. 16, pl. 2, figs. 2, 2a. 

Tauilus quartzite: Katzenloch, near Idar. 

1886. Curtonotus torosus. Maurer, Fauna des rechtsrheinischen Unterdevon (Darmstadt), p. 113 (not seen). 

1895. Cypricardella bicostula. Beushausen, K. preuss. geol. Lanclesanstalt Abh., new ser., vol. 17, p. 137, pl. 11, figs. 5-9. 

Taunus quartzite: Katzenloch, near Iclar; Stromberger Neuhiitte. 

Siegen graywacke: Seifen, near Dierclorf; Menzenberg, near Bonn. 

1904. Cypricard.ella bicostula. Drevermann, Palaeontographica, vol. 50, p. 243. 

Formations and localities same as cited by Beushausen, 1895. 

1 Billings, Elkanah, Paleozoic fossils of Canada,.vol. 2, pt. 1, p. 55, figs. 24-25, 1874. Not the Schizodus ventricosus (Billings) of Clarke (New York 

State Mus. Mem. 9, p. 162, pl. 23, fig. 10, 1908). 
MOLLUSCA. 249 

A transverse, complapate Cypricardella with strong concentric markings is represented 

by a large fragn1entary external mold of a left valve from the west side of Edmunds Hill. The 

specimen is 16 millimeters or more high, and was probably' 26 millimeters or more long. The 

ventral margin is bellied clown at the posterior extremity but only slightly arched in the middle. 

The posterior margin is slightly convex and strongly retrorse, and has the posterior extremity at 

tho respiratory angle, less than one-fourth the height above the base. The cardinal line is only 

slightly, if at all, greater than the height of the shell. The umbonal ridge is broadly rounded 

and inconspicuous. The body of the shell is depressed convex, the posterior slope flattened. 

The surface markings consist of concentric, almost bellistriate lines of growth, with distant, 

slightly stronger varices beginning at about the midheight of the specimen. 

Locality: Chapman sandstone, west side of Edmunds Hill (locality 1099 M:), Chapman 

Township, Aroostook County, ]tfaine. 

U.S. National Museum, catalogue No. 59829. 

Oomparisons.-In its large size, outline, and ornamentation the specimen is closely affiliated 

with Krantz's species 0. bicostula/ but the incompleteness of the single Chapman specimen 

1nakes identification with the German species doubt~ul. · It is safe, however, to consider the 

fossil as a member of the. group of large transverse, cmnplanate, semibellistriate forms, including 

0. unioniformis (Sandberger),t from the lowest Coblenzian of Singhofen; 0. bicostula (Krantz),2 

a widespread species in the German lowest Devonian, the Taunus quartzite and Siegen graywacke; 0. elongata Beushausen/ from the Siegen graywacke and Lower Coblenzian; and some 

forms of 0. tenuistriata Hall, 4 from the Middle and Upper Devonian of New York. 

Superfamily SOLENACEA Lamarck. 

Family SOLENIDJE Leach. 

Genus PALEOSOLEN Hall. 

The name Palreosolen was proposed by HalP in 1885 for the $pecies Orthonota siliquoidea 

I-Iall, 1870, which he recognized as differing frmn typical species of Orthonota " in the regularly convex, cylindrical forrn of the entire shell, and the gaping posterior extremity." 6 

Although in the description I-Iall gave Paleosolen subgeneric value, it was not as a subgenus 

of Orthonota but of Solen. No cardinal teeth have been observed in the original species, a 

negative chanwter which would seem to throw it into closer relationship with the Solenopsidre, 

of the Paleozoic, than with the Soleniclre, of Cretaceous to Recent time; ap.other species of 

Paleosolen, however, seems t;o show teeth as in Solen. In general external form, also, Paleosolen 

1nuch resembles the Recent representatives of Solen, which gape at both ends; McCoy's Solenopsis .gapes at the posterior end. Whatever may prove to be the true relationship between the 

Paleozoic and the Recent shells of this general form, it is evident that Paleosolen is not strictly 

a subsection of either Orthonota or Solen; but properly a separate genus of the Solenidre, a family 

of ancient geologic age; it is therefore ancestrally related to the true Soleus. 

In sepai·ating Pnleosolen from Orthonota, Hall cap.ed attention to the doubt regarding the 

type of Conrad's genus Orthonota, stating that the :first species mentioned by Conrad (0. pholadis) 

"is evidently not congeneric with 0. undulata, which Mr. Conrad a~ways regarded as the 

typical species of the genus." 7 In his redefinition of the genus Orthonota, Hall adopted 

0. und'l.tlata· as the type of the genus and cited 0. carinata as another example. Orthonota 

carinata and 0. ensiformis have sharply defined and angular posterior radial ribs or costre; in 

0. undulata, although it laeks the rigid ribs or costre, they are usually represented by faint radial 

1 Sandborgor, Ouldo n.ud Fridolin, Vcrstcinerungcu des rheinischen Schichteusystems in Nassau, p. 253, pl. 27, fig. 3, 1850. See also Bcushausen, 

Louis, op. cit., p. 139, pl. 11, figs. 17-19. 

2 Krantz, A., op. cit., p. 162, pl. 11, fig. 1. Sec also Beushausen, Louis, op. cit., p. 137, pl. 11, figs. 5-9. 

a .Bcushauscn, Louis, K. prcuss. gool. Laudosaustalt Jahrb., 1888, p. 226, pl. 4, figs. 3, 4, 1889; K. preuss. geol. Laudesaustalt Abh., new ser., vol. 

17, Jl. 138, pl. 11, figs. 10-14, 1895. 

1 Hall, James, Paleontology of New York, vol. 5, pt. 1, p. 310, pis. 42, 73, 74, 1885. 

~ Idem, fuse. 2, ~· 46. 

o Idom, p. 483. 

1 Idem, p. 14. 
250 FAUNA OF THE CHAPMAN SANDSTONE OF MAINE. 

furrows which are variable in number and strength. These furrows may, however, be lacking; 

indeed, suites of specimens of Orthonota undulata from the Hamilton formation at Sherburne 

and along Cayuga Lake, N.Y., contain mature shells that show no radial furrows. The absence 

of these. characters' alone, therefore, might not be regarded as geneJ,"ically separating 0. siliquoidea 

and Paleosolen from the typical Orthonotas. 

In Paleosolen, however, there is, in addition to the posterior gape, a pronounced anterior 

gape, effected by the reflexion or flaring back of the forward· portion of the shell. This reflexion 

of the anterior margin will serve to distinguish Paleosolen from Orthonota. The character is 

developed in Paleosolen siliquoidea, as was indicated by Hall, and also occurs in P. costatus 

(Sandberger), from _the Rhenish Eo-Devonian. Examination of extensive suites of Orthonota 

undulata and 0. carinata has failed to furnish any positive evidence of gape at either end; moreover, these species, representing typical Orthonota, lack the reflected anterior margin of Paleosolen. On the whole, I am inclined to consider Paleosolen as representing the primitive.Solenidre, 

whereas Orthonota and similar soleniform shells occurring in the older Paleozoic are, as suggested by Ulrich, of orthodesmoid-modiolopsoid affiliations. 

In Orthonota undulata and 0. carinata the two valves are, when conjoined, commonly 

spread out flat.; the valves are not closed. On the other hand, in the Chapman shells, although. 

the ligament appears to have been v~ry strong, the shells are usually fossilized, with the v~lves 

joined i_tnd closed. Paleosolen costatus (Sandberger) is also found generally with both Vialves 

joined together and not spread open. In this habit of the species the Paleozoic Paleosolen, unlike 

Orthono.ta, conforms to the habit of the Recent Soleus. Whether or not Paleosolen possesses 

the deeply insinuated pallial line of Solen is unknown. 

Paleosolen chapmani, described below, is the 2arliest solenoid known. The, genus includes, 

in addition to this shell, the following species: 

Solen costatus. Sand berger, Die V ersteinerungep. des rheinischen Schichtensystems in Nassau, p. 252, pl. 27, figs. 1-1d, 

1850-1856. Lowest Coblenzian, or Singhofen porphyroid, in Nassau; Wurben Valley quartzite of Durrberg, in 

the Altvater Mountains, Austrian Silesia. 

Paleosolen simplex. Maurer, Die Eauna des rechtsrheinischen Unterdevon, p. 18, 1886. Lower Coblenzian near 

Ehrenbreitenstein and Winnigen. Also recorded from the fauna of the Moose River sandstone of Moosehead Lake, 

Somerset County, Maine (Clarke, New York State Mus. Bull. 107, p. 235, figs., 1907). 

Solenopsis belgif:a. Kayser; Sur une faune du sommet de la serie rhenane a Pepinster, Goe et Tilff: Soc. geol. Belgique Mem., vol. 22, p. 202, pl. 2, figs. 8-9, 1896. Upper Eo-Devonian of Pepinster, Belgium. 

Paleosolen eifeliensis. Beushausen, Die Lamellibranchiaten des rheinischen Devon: K. preuss. geol. Landesantalt 

Abh., new ser., vol. 17, p. 225, pl.18, fi.gs.11, 12, 1895. Upper Coblenzian of Priim, in the Eifel. 

Sanguinolites? gracili:J. Walcott, Paleontology of the Eureka district [Nevada]: U. S. Geol. Survey Mon. 8, p. 175, 

1884. Eo-Devonian limestone of the Eureka district, Nev., with S.? combensis. 

Sanguinolites? combensis. Walcott, idem. 

Paleosolen siliquoidea. Hall, Paleontology of New York, vol. 5, pt. 1, Lamellibranchiata II, p. 483, 1885. Hamilton 

(Meso-Devonian) of eastern New York. 

Paleosolen occidentalis. Miller and· Gurley, New species of Paleozoic invertebrates from Illinois and other States: 

Illinois State Mus. Nat. Hist. Bull. 11, p. 16, pl. 2, figs. 13, 14, 1896. Chouteau limestone (Mississippian) near 

Sedalia, Mo. In the long escutcheon and deep lunette, as well as in the deeply impressed musc~ular scars, this 

shell seems to differ from the other Paleosolent:l. 

The genus Paleosolen has frequently been confused with Solenopsis McCoy 1 ( = Solenomorpha 2), but McCoy's genus includes Paleozoic solenoid shells in which the dorsal and ventral 

margins, instead of being parallel, as in the Soleus, converge or taper posteriorly, the anterior 

end is nearly or quite closed, and the posterior end gapes only slightly. 

t McCoy, Frederick, Synopsis of the characters of the Carboniferous limestone fossils of Ireland, p. 47, 1844. 

2 It was first pointed out by 1'. D. A. Cockerell in 1903 (Nature, vol. 67, p. 559, Apr. 16, 1903) that the generic name Solenopsis McCoy, 1844, 

was preoccupied, having been applied by ·westwood in 1841 (Annals and Mag. Nat. Hist., vol. 6, p. 86)· to a well-known genus of ants. Cockerell 

suggested the substitution of Solenomorpha for Solenopsis McCoy. The generic name Solenella had been applied to one of the species of Solenopsis 

by De Ryckholt in 1847 (Melanges paleontologiques, pt. 1, pl. 11, fig. 17) and would take precedence over Solenomorphain supplanting Solenopsis 

were it not that Solenella was itself preoccupied for a different genus of lamellibranchs. Solenomorpha will therefore stand as the substituted name 

for McCoy's Solenopsis. Solenomorphahas been used by Wheelton Hind (Geol. Soc. London Quart. Jour., vol. 59, p. 334, 1903; Monograph ofthe 

British Carboniferous Lamellibranchiata, vol. 2, pt. 3, p. 159, 1904). · · 
MOLLUSCA. 

F'ALEOSOLEN CHAPMAN! sp. nov. 

Plate XXIV, figures 1, 3, 5, and 7. 

cf. 1,.896. Solenopsis belgica. Kayser, Soc. geol. Belgique Mem., vol. 22, p. 202, pl. 2, figs. 8-9. 

Eo-Devonia.n (zone of S]Jirifer dai:eidensis and S. subcuspidatus): Pepinster, Belgium. 

1907. Palmosolen simplex (not Maurer). Clarke, New York State Mus. Bull. 107, p. 235 (pars). 

251 

[Lower Devonic]: Presque Isle Stream, Chapman Township, Aroostook County, Maine (not Moosehead Lake). 

Shells narrow, solenoid, with dorsal and ventral margins subparallel. Length in complete 

tnature specimens (55 to 56 n1illimeters) about 6~ times the height (8.5 to 10.25 n1illimeters); 

in younger, apparently complete specimens the length (16.5 millimeters) is less than 3~ times 

the height (5 millimeters). Tho umbones are between the anterior eighth and ninth, very broad 

and inconspicuous, hardly extending to the cardinal line. The cardinal line is uninterrupted 

in front of and behind the beaks; it is horizontal, generally slightly convex, occasionally straight; 

the portion posterior to the beaks is equal in length to five or more times· the height of the shell. 

The cardinal extremity is obtusely angular. The posterior margin is truncate, appreciably 

retrorse; it is generally slightly convex, occasionally nearly straight; the hindmost extremity 

is at the inferior third or fourth. In the lower portion the posterior margin is convex and vertical, forming a rounded right :angle into the ventral margin. The ventral margin is horizontal 

and straight near the posterior end, also near the anterior end, but it is commonly broadly 

insinuated, producing an obscure concavity in the ventral outline. Young shells frequently 

lack the ventral concavity in the outline. Toward the front end the ventral margin ascends 

into the anterior extremity, which is well developed and 'equal in length to the height of the 

shell. 

The anterior end is conspieuously gaping and the extreme anterior edge is reflexed. In front 

of the beaks the dorsal n1argin extends 'forward, descending only slightly for a distance equal 

to four-fifths the height of the shell and including the major part of the length of the anterior 

end. Through this distance the dorsal margin is tightly shut, but, beginning at the forward 

end of this line, the anterior n1argin is abruptly deflected out of its plane, producing a wide 

gape which is increased toward the midheight of the anterior margin and below by the reflexe~ 

anterior surface of the shell. The amount of gape is greatest at the midheight and continues 

below and into the ventral rnargin, where the gape is continued to a point well behind the 

beaks. The ventral margins 'close gradually and over the concave portion seem to be shut. 

Posteriorly the specimens examined were not well preserved, but seem to indicate that the 

ventraltnm·gins again gradually separate and that the ventral gape gradually widens toward 

the rear; the posterior n1argin appears to be truncate and widely gaping, somewhat like the 

anterior margin, though no reflexion is apparent in the ·posterior margin. ·The dorsal margin 

is closed throughout. The thickness of both. valves in conjunction is less than the height of 

the shell, the proportion vary-ing from 59:100 to 2:3. In some specimens the greatest thiclmess 

or depth is at the midheight, just behind the beaks; in others it appears to be on the rounded 

umbonalridge much farther lback and higher up, just in front of the midlength and in the upper 

third or fourth. Between these two points of greatest convexity the surface is depressed, 

almost flattened, and frequently slightly concave. The umbonal ridge is broadly convex and 

indistinct. Between it and the cardinal line, nearer the latter, there is a radial furrow or sinus, 

which does not quite reach the umbones. This sinus is variable in appearance and development, but is rarely entirely absent. Commonly it is distinct but shallow. Between the shallow 

posterior sinus and the liga1nental platform there is a very low rounded ridge. An abruptly 

flattened external ( ~) ligamenta! strip extends along the cardinal line to the hinge extremities. 

Just behind the umbones there is a depression inthe cardinal line which extends for a very 

short distance, not more than the height of the shell and apparently less. This depression 

semns to be bounded below by a ridge or rounded septum. The structure probably corresponds 

to that of the ligamenta! escutcheon and internal ridge in the typical species of Recent Solen 

and Ensis. Beyond this excavated escutcheon the cardinal line is elevated, and both valves 

meet dorsally in a sharp edge. Below this cardinal edge there is a well-developed flattened 

strip which extends to the hinge extremities and which corresponds to a similar external st~ip 

in the Recent Solen and Ensis. 
252 FAUNA OF THE CHAPMAN SANDSTONE OF MAINE. 

Dentition unknown. Not the slightest indication of muscular scars or pallial line is discovered in well-preserved fossils, and probably neither was impressed upon the shell. 

The surface ornamentation consists of very fine lines of growth parallel to the margin; 

Along the ventral margin these Jines are fine, but in curving upward parallel to the dorsal 

margin some of them gradually become lamellose; in some shells the surface becomes concentrically wrinkled posteriorly, but this wrinkling is never so persistent nor so well developed 

as in Orthonota undulata Hall. The postumbonal slope is variable in appearance, being marked 

generally by the fine distant lamellre, less commonly by the very fine lines· of growth,. an occasional 

one of which may be slightly strengthened into a sort of varex; very rarely the lines of growth 

:inay be accumulated into the low, rounded obsolescent wrinkles. The fine lamellre are somewhat similar to those of Solen (Paleosolen) costatus Sandberger 1 but are never so even, so close, 

or nearly so well developed. The ornamentation is not interrupted nor constricted by the 

posterior sinus below the hinge line. On the extreme anterior end the fine lines of growth are 

again generally strengthened, and this part of the shell, the extreme anterior margin, is either 

finely imbricose-lamellate, finely undulate, or, rarely, simply marked by fine concentric lines. 

The largest specimen is a fragment 10.25 millimeters high and 47 millimeters long. It is 

in'complete posteriorly, but originally it was probably more than 60 millimeters long. Specimens 8 or 9 millimeters high are common. The only complete specimen is 8.5 millimeters high 

and 56 millimeters long. 

Locality: Chapman sandstone, along Presque Isle Stream at end of Tweedy road (locality 

1099 A), Chapman Township, Aroostook County, l\1aine. 

U.S. National Museum, catalogue No. 59830. 

Oomparisons.~In general outline and ornamentation Paleosolen chapmani resembles the 

German Eo-Devoruan shell P. costatus (Sandberger), but the German shell differs from P. chapmani in having a shorter anterior end, a less retrorse and less convex posterior margin, and a 

more regular, even imbricate poster~or ornamentation, which changes abruptly from the surface 

ornamentation of the body of the shell. P. costatus also lacks the posterior radial sinus below 

the hinge and is a larger shell than P. chapmani. · 

Some few specim~ns of the Maine shell which are undulose or semi-imbricostate undulose 

posteriorly slightly resemble Orthonota undulata, but that species is much more evenly undulose; 

it also lacks the ventral sinus, and the change in its ornamentation posteriorly is n1uch more 

abrupt. Finally, Orthonota undulata does not gape, like Paleosolen. 

Some young specimens of P. chapmani resemble the English Silurian shell Orthonota rigida 

(Sowerby), 2 but 0. rigida is.much shorter, has a convex ventral margin and a double posterior 

sinus, and is more strongly marked anteriorly and in the middle -and less strongly marked 

posteriorly; the character of the ·gape, if any gape is present, is unknown. 

The species most closely approaching P. chapmani is the Paleosolen from Pepinster, Belgium, described by Kayser 3 as Solenopsis belgica. It is indeed difficult to define any really 

satisfactory characters by which to separate the two, owing to the incompleteness of the fragments described and figured by Kayser. The ornamentation is almost precisely similar and 

similarly variable; Kayser's figure 9 (the ~ight valve) 13hows the radial posterior sinus as in 

P. ch~pmani, and in both species this seems to be sometimes a little stronger in the right valve 

than ·in the left. One important distinction lies in the fact that the posterior margin is much 

more retrorse in Paleosolen belgica (Kayser) than in P. chapmani); moreover, in the latter 

the posterior margin is convex, whereas in the Belgian fossil it seems to be slightly concave. In 

the Maine shell the ventral margin is generally obscurely concave; in P. belgica it appears to be 

straight. · 

1 See Beushausen, Louis, op. cit. 

2 Salter, J. W., ·Paleontological appendix to John Phillips's memoir on the Malvern Hills: Geol. Survey Great Britain Mem., vol. 2, pt. L, p. 362, 

pl. HJ, figs. 1, 2, 1848. The name Orthonota rigida Hall, 1885 (Paleontology of New York, vol. 5, pt. 1, p. 481, pl. 80, fig. 6, 188.5), is therefore preoccupied, but tho English Silurian and-American Devonian shells may not be congeneric. 

a Kayser, Emanuel, Sur une fauna du sommet de Ia serie rhenana a Pepinster, Goe et Tilff: Soc. geol. Belgique Ann ales, vol. 22, p. 202, pl. 2, 

figs. 8, 9, 1896. This s~ell occurs in an Eo-Devonian fauna associated with Spirifer subcuspidatus var. alatus Kayser, S. daleidensis Steininger, and 

Productella subaculeata Murchison and is apparently high Eo-Devonian. 
MOI:-LUSCA. 253 

As has been indicated, P .. chapmani has certain features in common with Recent shells. 

In Solen siliqua Linnreus (Europe), Ensis americana Beck, Ensis ensis Linnreus (Europe), and 

Ensis g1·acilis Gray (Cape St. :Lucas), in which the escutcheon and especially ~he external 

posterior flattened strip below the cardinal line are well developed, the escutcheon is a little 

longer than in Paleosolen chapmani. In the Recent shells the escutcheon is· perceptibly greater · 

in length than the height of thee shell; in the Chapman fossil it is hardly equ~1.l to th~ height. 

The external flattened strip ex~ends all along the cardinal line to the hinge extremity in the 

Chnpman fossil; in the ·Recent :Solens and Enses named the strip expands in width toward the 

midlength, co'ntracts posteriorly·, and does not quite reach the hinge extremity. In the short 

escutcheon and long, well-developed posterior infracardinal strip, and also in the ventral constriction or insinuation and consipcuous anterior end, P. chapmani conforms with the Recent 

Macluera, but of course the outline is different, being typically sol~noid in the Maine fossil. 

Among the Recent So lens an u,nterior end is developed in only a few species, as S. ambiguus 

Lamarck (Guadeloupe, West Indies) and Solen gladiolus Gray (Panama); in these two species 

the ventral margin is insinuated and the antm·ior margin reflected as in Paleosolen chapmani, 

:producing a very close resemblance generically to the Maine shell, which is, however, distinguished by its different manner of gape. In Paleosolen chapmani the dorsal margins of the 

two valves meet in front of the umbo in a closed dorsal edge which indudes most of the upper 

half of the anterior end. In the two Recent species just named the gape begins immediately 

at the beak. In all the Recent. Solens the gape continues and includes most of the ventral edge 

of the valves, and the two valves do not meet ventrally except near the posterior end. In 

.P. chapmani the two valves seem to meet ventrally only a short distance behind the umbones 

and to diverge again posteriorly. Most of the ventral margin, including all the middle portion, 

is apparently closed. InS. ambiguus and S. gladiolus the flattened strip below the posterior 

·dotsal edge is not perceptibly developed. 

Genus CIMITARIA Hall. 

'The following is Hall's description 1 of the genus Cimitaria, which was originally promulgated in 1869: 2 • 

Shell equivalve, extremely inequilateral, transversely elongate; form solenoid, falcate, or elongate-trapezoid. 

Anterior end short and rounded. PoE1terior end elongate, the extremity truncate. Beaks strongly incurved; umbones 

prominent. Cardinal line straight or concave. U.mbonal slope angular and often strongly defined. Surface marked 

by strong concentric lines of growth, which are simple or lamellose, and by fine radiating strire, which may be more 

or less strongly marked or altogether obsolete; a more or less distinct depression or cincture extends from the umbones 

in ,a slightly posterior direction to the basal margin. The hinge is marked by a narrow, elongate ligamenta! groove, 

and anterior to the beaks is a strongly defined lunule. Ligament external. Teeth unknown. Muscular impressions 

and pallial line undetermined. Tho species placed under this genus are remarkable for their transversely elongate 

forms, the greater portion of which iE• posterior to the beaks. Some of the forms bear a resemblance to Orthonota, but 

the hinge line shows a distinct ligamenta! groove and the anterior margin is rounded, with a well-defined lunule. The 

species are closely allied .to Pholadella, and when more forms become known it may prove convenient to unite the 

genera. In some important points the genus approaches Grammysia by the way of Allorisma. The marked external 

ligamenta! area and strong lunule are common to the three genera, while the surface markings have many points in 

common. In the absence of critical knowledge of the hinge structure, we are unprepared to make any more positive 

assertion regarding this genus and itB allied form!;!. 

Examples: Cirnitaria recurva (Conrad), pl.. 77, figs. 9-14, p. 467; Hamilton group. Cirnitaria elongata (Conrad), 

pl. 77, figs. 5-8, p. 466; Hamilton group. Cirnitaria corrugata (Conrad), pl. 77, figs. 1-4, p. 465; Hamilton group. 

A character of prime importance which was overlooked by Hall is the fact that the posterim· extren1ity is strongly gaping, as may be observed in his figure ll of Oimitaria recurva. 

The typical forms of ·Cirnit.aria constitute a well-known group of shells of the :Middle and 

Upper DeYonian of New York recognizable by their rather large size and characteristic transversely extended scimitar-lik·a outline, length about three or more times the width; well-developed umbonal ridge and concave posterior slope; umbones inflated, arching over the cardinal 

line, directed upward or nen.rly so, incurYed, and nearly terminal. The broad ventral sinus, 

l Hrul, JGmos, Pllloontology of New York, vol. 5, pt. 1, rase. 2, p. xlii, 1885. 

t Hllll, James, Preliminary notice of the lamellibranchiate shells of the upper Helderberg, Hamilton, and Chemung groups, pt. 2, p. 66, 

.December, 18G9. 
254 FAUNA OF THE CHAPMAN SANDSTONE OF MAINE. 

nearly vertical, but slightly oblique posteriorly, is a constant feature in these typical forms. 

Among the more diagnostic features are the strong anterior lunule and lunette and long external 

posterior ligamenta! groove or escutcheon; the nonpreservation of muscular scars (internal 

molds are usually glossy except in very coarse sediments); and the gaping posterior extremity. 

An apparently typical recurved Cimitaria, which, however, is a little smaller than the New 

York Devonian shells, is the Leptodomus borealis of Tschernyschew and J akowlew, 1 fron1 the 

middle.or late Silurian faunas of Cape Grebeni, on the island of Waigatsch, off the northeast. 

coast of Russia. In its small size this Silurian species conforms with the supposed Eo-Devonian 

members of the genus Cimitaria. 

The typical Cimitarias, in their large size, scimitar-like outline, convexity, concentric, and 

granulose ornamentation (though the granules are very rarely observable), lunette and long 

escutcheon, and posterior gaping, resemble the genus Chrenomya Meek and I-Iayden,2 1864, of 

which the type is 0. leavenworthanus Meek and Hayden. Half a dozen or n1ore species are 

known in the upper Mississippian to Permian strata of the Mississippi Valley. Meek and 

Hayden also refer to Chrenomya a couple of 3"uras$ic fossils from Europe. This genus differs 

from Cimitaria in having the posterior extremity reflected so as to produce a wider and more 

flaring gaping, whereas in Cimitaria the gaping is not produced by any conspicuous reflexion 

of the posterior margin and is much less pronounced. The sinus present on the surface below 

the umbones in all the typical Cimitarias is absent in Chrenomya, where the body of the shell 

is evenly convex; the umbonal ridge is somewhat more strongly pronounced in Cimitaria. 

Finally, Chrenomya has a distinct pallial sinus (in the typical Pennsylvanian-Permian forms), 

and the hinge is edentulous. In Cimitaria the pallial line and hinge features are unknown. 

From the typical Cimitarias may be. dissociated the apparently grammysioid, nongaping 

genus Pholadella Hall, which is marked by prominent raised, persistent radial lines or riblets. 

The allied genus Cercomyopsis Sandberger ( = ~Physetomya Ulrich) resembles Cimitaria but is 

distinguished by having a comparatively large body and a smaller, acutely tapering posterior 

portion, the beaks not quite terminal, the surface marked by concentric undulations or ridges 

on the body crossed by tenuous radial or vertical striations, and the posterior slope smooth. 

Both Pholadella and Physetomya have already been referred to in the discussion of the genus 

Grammysia, to which they seem to be more closely related than to Ciniitaria, to judge fron1 

existing incomplete evidence. A subgroup that may be separated from typical Cimitaria might 

be designated the group of Oimitaria?chapmani sp. nov. It includes besides that species, which 

occurs in the Chapman sandstone of Maine, the following species: 

Sanguinolites decipiens. McCoy, British Paleozoic rocks and fossils, p. 277, pl. 1, L, fig. 24, 1852. Upper Ludlow of 

Benson Knot, near Kendal, Westmoreland. 

Cimitaria karsteni. Clarke, The Devonian Mollusca of the State of Para, Brazil: Mus. nac. Rio de Janeiro Arch., voL 

10, p. 60, pl. 8, figs. 18, 19, 1899 (author's English ed., 1900). Lower Coblenzian formation, Rio Maecuru, _Para, 

Brazil. 

Pholadella parallela. Hall, Paleontology·of New York, vol. 5, pt. 1, p. 470, pl. "78, figs. 22-24, 1885 .. Hamilton formation throughout New York State. 

The Arctic Silurian 0. borealis (Tschernyschew and Jakowlew) may also be included in 

this subgroup, and possibly Sphenotus ellsi Clarke 3 (pars), from the late Silurian 0) of Dalhousie, New Brunswick, and Oimitaria elongata (Conrad), 4 from the Hamilton of New York. 

0. elongata lacks the recurvature of typical Cim.itaria and has prosogyrate beaks; it is also 

smaller than any of the typical Cimitarias though larger than any of the other members of the 

group of 0. chapmani. 

The shells of this subgroup are easily distinguishable from the typical Cimitarias by their 

much smaller size. Their length does not exceed twice the width, and the umbones are prosogyrate (directed forward). The lunette and long escu~cheon are developed in Oimitaria? 

1 Tschernyschew, T., andJakowlew, N., DieKalksteinfaunadesCap Grebeniaufder Waigatsch-Insel und des Flusses Nechwatowa auf Nowaja 

Semlja: Russ.-k. min. Gesell. St. Petersburg Verh., vol. 3G, p. GG, pl. G, figs. 17-19, 1899. 

2 Meek, F. B., and Hayden, F. V., Paleontology of the upper Missouri: Smithsonian Contr. No. 172, p. 42, 1864. 

a Clarke, J.' M., New York State Mus. Bull. 107, p. 226, lower figures only, 1907. 

4 Hall, James, Paleontology of New York, vol. 5, pt. 1, p. 4GG, pl. 77, figs. 5-8, 1885. , 
MOLLUSCA. 255 

chapmani and Sanguinolites decipiens McCoy, and the former shows obscure indications of 

having been gaping posteriorly; these features have not been noted in the descriptions of the 

other species of this little group. As ]n Cirrutaria, the muscular scars,. pallial line, and dentition aro unknown. There is a well-developed umbonal carina in all the species, and a wide, 

concave, almost s~nooth posterior slope. The body of the shell is inflated, with overarching 

u:mbones, and a sinus extends below the beaks in all the species except Oimitaria karsteni Clarke, 

which is without sinus. The surface is lnarked by concentric strire of growth, son1etimes aggregated anteriorly into undulations and apparently granulose; these are usually less pronounced 

p os teri orly. · 

Although this little group ranges from the uppermost Silurian through the Lower Devonian 

to the Middle Devonian, typical large Chnitaria is probably confined to the· Middle and Upper 

Devonian. 

The group of Oimita1-ia? .chapmani recalls in many of its features the genus Cuneamya I-Iall 

but is distinguished frmn Cunea~nya by the gaping postetior and superficially by the more distinctly. carinate u.mbonn1 ridge. 

CIMITARIA ~ CHAPMAN! sp. nov. 

Plate XXIV, figure 16. 

cf. 1852. Sanguinolites decipiens. McCoy, British Paleozoic rocks and fossils, p. 277, pl. 1, L, fig. 24. 

Upper Lndlow: Benson Knot, near Kendal, Westmoreland. 

Length (22 :m.illimeters) bnrely exceeding twice the height (10.5millimeters); greatest height 

on the un1bones at the anterior three-tenths; greatest length indefinitely below the middle and 

probably nearer the basal)nargin, the most posterior point being near the base, the most anterior 

point at the midheight. Umbones inflated, incurved, arching a little over the hinge line, slightly 

prosogyrate; beaks between the anterior fourth and filth. The cardinal line is rigid, straight, 

horizontal, or slightly declining, :in length (from beak to postcardinal extremity) about one and 

one-eighth times the height of the shell. The cardinal extremity is angular, obtuse (140°), 

situated at the posterior sixth. The posterior n1argin is truncate, retrorse, almost straight, 

slightly convex, especially at the base, where it curves into the rounded respiratory "angle." 

The )nost posterior point of the posterior ~nargin i::; at or very near the base. The ventral 

:margin is conspicuously insinuated; the posterior half is horizontal and parallel with the cardinal line anterior to the insinuation, which extends at an angle of 40° to 45° posteriorly downward fron1 the beaks; the ventral margin is convex, a little lower than the posterior half and 

curving into the anterior end. The lowest point of the ventral margin is below the beak, at 

the anterior fourth, where the height is equal to about one and one-third times the height of 

the posterior half of the shell. The anterior end is rounded and very short; the forward extremity is at the midheight, above which the l.nargin recedes upward in a shallow lunule to the 

bettk. The depth of the single ·left valve known (4 millimeters) is three-eighths the height, or 

nearly a ftfth the length. The point of maximu~n depth is on the umbonal cnrina, just back 

of the middle and at three-fifth::; the height above the base. One of the most conspicuous 

feu.tures is the high sign1oidal earina, the curvature of which is convex over the postumbonal 

portion and straight or concave below; the carina is sharp throughout, especially toward the 

un1bones. Posteriorly the surface descends into a smooth concave slope to the top of the 

escutcheon. Anterior to the e:arina the body of the shell is inflated and n1arked by a conspicuous though shallow, unde1ined broad sinus extending from the carina forward to a point 

below the beaks. The anterior half of the body of the shell is strongly convex. The sinus 

extends posterjorly downward from the umbones to the basal margin at nn angle of approxiPlatoly 40° to 45°. Anterior to the beak there is a fairly well developed lunette occupying a 

shallow lunule. Posteriorly there is a .strongly excavated escutcheon, or external ligamenta! 

groove, about 1 millbneter, thiek (in the left valve) at the un1bo, tapering toward the posterior 

extremity and extending nearly, if not quite, the entire length of the cardinal line. Dentition 

unknown. Shell structure unknown. The "sculpture cast" is. peculiarly glossy and d.trk in 

color. Obsct,re and doubtful indications of granulation cross the concentric n1arkings. Museu-
256 FAUNA OF THE CHAPMAN SANDST'ONE OF MAINE. 

· lar and pallial line unknown. The difficulty of observing such features as the gaping in a 

single internal mold or" sculpture cast" of an isolated left valve embedded in the rock, especially 

when parts of the margin have been clipped away, is apparent, and the features of the gaping 

described below should be considered as far from conclusiv:ely prove~. The anterior end appears · 

-to have been perceptibly gaping, as may be observed by holding the cardinal line and anteroventral margin on a plane with the eye. This appearance of gaping may, however, be due 

to the breaking away of a piece of the shell. from the anterior end. The posterior and postventral margins also appear to be gaping, with the maximum gape at the respiratory angle. 

· Posterior to the carina the surface appears to be quite smooth, but exceedingly tenuous lines 

of growth may be observed parallel to the posterior margin. The body of the shell is crossed by 

coarse lines of growth aggregated into obsolescent, narrow, concentric, irregular undulations, 

which are most conspicuous on the convex portion below the beaks in front of the sinus and 

imme.diately in front of the carina. · 

Length, 22 millimeters; height, 10.5 millimeters; depth of left valve a trifle over 4 millimeters. 

Locality: Chapman sandstone, Presque Isle Stream at end of Tweedy road (locality 1099A), 

Chapman Township, Aroostook County, Maine. · 

U.S. National Museum, catalogue No. 59831. 

Oomparisons.-Thi~ species may prove to be identical with McCoy's Sanguinolites decipiens. 

The Chapman fossil differs in only a few doubtful minor respects from McCoy's description of 

his species, which is as follows: 

Elongate, oblong, dorsal, and ventral margins supparallel; beaks incurved, small, depressed, about one-fifth the 

length from the anterior end; hinge line long, not elevated (the inflected edges forming a nearly horizontal posterior 

lunette extending its entire length); cardinal angle about 115°; anterior end rounded, narrowed by a large elongate, 

elliptic lunette; a strong, sigmoidally contorted diagonal ridge extends from the beak to the respiratory angle; posterior 

slope steeply inclined; posterior end slightly oblique, subtruncate, rounded; ventral margin with a wide, rather deep 

sinus in the middle, from which a wide concavity extends nearly to the beak, and from the diagonal ridge to the anterior 

end, which is convex anterior to the beak~; surface marked with sharp concentric wrinkles from the anterior lunette 

to the diagonal ridge. Length, 8lines; in proportion to the length greatest width (from beak to opposite margin)&, 

length of anterio1 end ..ftPrr, from beak to end of hinge line !ritJ, greatest depth of one valve (about middle of diagonal 

ridge) NrJ. 

I have seen numerous specimens of this species from the Upper Ludlow rocks, usually confounded with the socalled Cypricardia eymbijormis (Sowerby), which it strongly resembles at first sight, altho~gh the anterior end is considerably longer. That fossil, however, has simple erect dorsal margins and belongs to the genuJI Orthonotus as restricted 

in this work, while the distinctly inflected d,orsal edges forming the elongate; concave, posterior lunette show the present 

species to belong to the genus Sanguinolites. 1 

rrhe anterior end is a little larger. in 0.? chapmani than it appears to be in :McCoy's figure, 

and the forward extremity is at the midheight, with a shallow concave lunule above to the 

beaks. In McCoy's figure the anterior extremity is near the base, and there is no concave 

lunule below the beaks; but the figure seems to be incomplete in the anterior end, and }.1cCoy, 

in his description, mentions specifically the presence of a lunule. The ventral insinuation 

semns to be a little more pronounced in 0.? chapmani, and the ventral margin tJ.nterior thereto 

is more deeply bellied down, but the posterior margin, though destroyed in the Chapman fossil, 

appears from the faint lines of growth to have been slightly less arched than in McCoy's species. 

Finally, in McCoy's species t1.e depth of ·the single valve is one-fourth the length, whereas 

in the Maine fossil (which is a little crushed) it is only one-fifth the length. The differences indicated may prove to be accidental or individual chara.cters; but for the present the Chapman 

shell may be listed as specifically distinct from the Upper Ludlow English species. 

Of the other species of the group of Oi1nitaria? chapmani, 0. lcarsteni may at once be 

distinguished by the absence of the ventral insinuation. 

The Sphenotus ellsi of Clarke's lower figure resembles 0.? chapmani, but the Maine species 

has a slightly ;more convex posterior margin and the ventral margin is more bellied down 

anteriorly, causing the greatest height of the shell to be under the umbone, whereas in 

1 McCoy, F., British Paleozoic rocks and fossils, p. 277, 1855. 
MOLLUSCA. 257 

Sphenotus ellsi the greate.:·~ iwight is posteriorly, a::; in McCoy's species. Clarke's shell nut.y 

possibly belong to the group of Oimitaria? chapmani. Sphenotus ellsi, as represented by Clarke's 

upper figure, is a more transversely elongate shell having the postumbonal radial ridge and 

groove of Sphenotus. Superfamily LUCINACEA. 

Family LUCINIDIE Fleming. 

C)enus P ARACYCLAS Hall, 1869. 

The genus Paracyclas Halll is easily recognized among Paleozoic lamellibranchs by the 

circular or subcircular outline; beaks minute, and central or nearly so; surface evenly rounded; 

ligament internal, n1ore or less supported by septa, one on each side of the beak with commonly 

an abruptly flattened strip over the posterior ligamenta} region. The genotype is P. occjilentale 

Hall and yvbitfield ( =P. elliptica Hall, 1843, not (Phillips), 1841). 

Lucina (Pm·acyclas) elliptica var. occidentalis is coinmonly accepted as a synonym of P. 

elliptica Hall. I-Iall's name,. however, is preoccupied by P·ullastra elliptica Phillips, 1841, 

which is regarded by De Koninck (1898) as a Paracyclas. The name Paracyc'las occidentale 

may therefore be applied to the American P. elliptica. 

The typical species Paracyclas elliptica I-Iall (not (Phillips) De Koninck) and P. lirata 

Com-ad are very common in the Ame~ican Corniferous, P. lirata continuing into the Hamilton, 

and extending upward in eastern New York into the lower part of the Portage formation. 

A couple of species are known in America in the higher Chemung of Pennsylvania and the 

Ouray limestone of Col01·ado. In Europe the genus occurs in the Carboniferous, according 

to Beushausen and De Koninck,1 and ranges nearly throughout the German Devonian, from 

the upper Neo-Devonian do\Vn to' the Lower Coblenzian, near the base of the Devonian of the 

Rhine 2 and the Harz. One species (Paracyclas lebescontei Barrois 3) has been found in the 

Lower Devonian of France, and the genus also occurs in the D'Qvonian of England, Spain, and 

Australasia. 4 It is, in fact, of world-wide range in the Devonian rocks. 

Paracyclas is also found in the Silurian. In England typical forms of the genus include 

several small species like lYfytii~us quad1·atus Salter,5 from the Upper Ludlow of Llangadoc; 

Mytilus perovalis Salter, 6 from the Ludlowian of Usk; and Anodontopsis bulla McCoy/ from 

the Upper Ludlow of Kendal, 'iVest:m.or.eland, and Galway, Ireland 0). 

BaiTande 8 has des·cribed a gigantic form, Paracyclas bohemica, from etage E2 of Bohemia 

(equivalent of the Aymestry of England). If this form belongs to the genus, which is somewhnt doubtful, it is the largest as well as·the earliest species of Paracyclas known. 

Paracyclas may therefore be regarded as probably first appearing in Aymestry or 

approximately Guelph time, becoming widespread in the late :middle Silurian or upper Silurian, 

attaining its :maxi:mun1 in the Devonian, and continuing into the Carboniferous. 

Paracyclas is easily distinguished fron1 the other Paleozoic lucinoids. Ilionia Billings has 

a large anterior end· toward which the s:m.all beaks are directed, and the small posterior end is 

sinuated or broadly el-uarginate postventrally. The ::;hell is co1npressed and is concentrically 

striated. Prolucina Dall, 1896, which appears to be a synony:m. of Ilionia, is a widespread 

genus in the Ayn1estry zone of Europe and in the Guelph dolon1ite of America and continues 

·into the Manlius and "'Corniferous" of America. It was founded on Lucina prisca (Risinger), 

fron1 the Ay:tnestrian fauna of Gotland. This species is considered by Lindstrom, Da:m.es, 

1 Do Koninck, L. G., Descriptions of the Pal!Jozoic fossils of New South Wales, Australia: Gcol. Survey New South Wales Mom., Paleontology, 

No.6, p. 85, 1898. · 2 Boushauson, Louis, Die Lamollibranchiaten des rheinischen Devon: K. prcuss. gcol. Landcsanstalt Abh., new ser., vol. 17, pp. 65 ct seq., 1895. 

, a Barrols, Charles, Fatmc du calcaire d'Erbrn.y, Loirc-Infericurc, p. 179, pl. 11, fig, 13, 1889. 

4 Do Kouinck, L. G., op. cit., p. 85. 

G Ph1llips, John, and Salter, J. W., 'fhc MalYcrn Hills compared with the Paleozoic districts of Abberley: Geol. Survc~ Great Britain Mom, 

vol. 2, pt. 11 p. 3(i3, pl. 20, fig. 1, 1848. 

o Idom, p. 3631 pl. ·20, fig. 2. 

7 Sedgwick, Adam, and McCoy, Frederick, British Paleozoic rocks and fossils, p. 271, pl. 1, K, figs. 11-13, 1852. 

s Barrandc, Joachim, Systllme silurien du centre de la Bohlline, ~t. 1, vol. 6, pl. 67, box III, pl. 129, 1881. 

50245°-No. 89-16-17 
258 FA"{!NA OF THE CHAPMAN SANDSTONE OF M~INE! 

and other European authors to be congeneric with Ilionia. If L. prisca does not belong to 

Ilionia, the name Platymermis, applied by Notling in 1883 to the sa1ne species, has priority · 

over Prolucina. 

A shell which might be confused superficially with the circular Paracyclas is the gentis 

Ontaria Clarke, including the world-wide· Oardiola concentrica Von Buch of the Upper Devonian 

Intumescens zone. This weir-known fossil differs from Paracyclas in being hingeless, as well 

as in its peculiar development of postdorsal radial strire. 

PARACYCLAS BULL~>IDE.S sp. nov. 

Plate XXV, figures 23, 23a, 24. 

Shells small, circular to quadrate-circular, the length equal to or slightly gceater than 

the height. Greatest height and length in the middle. Umbones inconspicuous, depressed, 

situated in the middle or slightly in advance of the middle. The upper margin of the anterior 

end extends forward, slightly descending from the beaks; it is flatly arched, nearly straight, and 

devoid of lunule, and it curves into the long, nearly vertical, rounded anterior margin, which 

curves similarly into the rounded ventral margin, and the latter into the posterior margin. 

The posterior margin is convexly rounded throughout and is not indented. The hinge extren1ity 

is rounded but approaches angularity more nearly than any other" corner" of the shell. The 

hinge line is nearly horizontal, descending slightly to the rear. It is gently convex, nearly 

straight. Shell moderately convex. The surface is subspherical, slightly more inflated unlbonally than ventrally. There is discernible on internal molds, along the dorsal margin, ·a more 

or less well-developed flattened strip. Occasionally, also on internal molds, there is .a flattened 

·or subconcave rim around the lateral and ventral margins of the shell outside and below the 

muscular scars and pallial line. The depth of the single valve is about one-fourth the height. 

The· point of greatest depth is below the umbones, at the upper two-fifths or three-sevenths 

the height. , 

Ligament internal. It is supported near the un1bones by an internal septum, which 

continues backward, diverging slightly from the hinge line, and arm;m.d to the upper hind part 

of the posterior muscular scar, where it dies out. This septum in Paracyclas n1ay serve as a 

muscular support, as suggested by Beushausen; rather than as the lower part of the ligamental 

groove, or it may possibly be the base of a broad hinge plate. Structure of anterior end not 

observed. Dentition unknown. Muscular scars faintly impressed, apparently both of th~m 

elongate in outline and extending below the midheight of the shell. .Pallial line simple,· faintly 

impressed; parallel to the ventral and lateral margins, and continuous into the distal margins 

of the muscular scars. One of the best-preserved specimens shows delicate radial or vertical 

striations above the pallial line in the middle and posterior portions of the interior of the shell. 

Internal molds are smooth, devoid of ornamentation. This is the usual mode of preservation .. The surface ornamentation has been observed only on a small fragment, dorsally, 

where the shell is marked by concentric broad strire .or grooves depressed below the surface, 

giving the appearance of concentric lirations, somewhat as in P. lirata but less conspicuous. 

The type specimen has a length of 10 millimeters and a height of 9.1 millimeters. Another 

specimen is 9 millimeters high and 9.66 millimeters broad; a third has a height of 10 millimeters 

and a length of 10 millimeters. · 

The species is easily recognized by its small size and circular to quadrate-circular outline. 

Locality: Chapman 'sandstone, 2 miles west of Presque Isle Stream (locality 1099 J), 

Chapman Township, Aroostook County, Maine. 

U.S. National Museum, catalogue No. 59832. 

Oomparisons.-P. bulloides re·sembles some. English la\e Silurian species, among them 

Mytilus perovalis Salter,! from which it is distinguished by having the umbones more nearly 

central and the height more nearly or quite equal to the length. The Chapman shell is also 

more convex. The two fossils appear, however, to be closely related specifically. 

1 Salter, J. W., Great Britain Geol. Survey Mem., vol. 2,' pt.·l, p, 363, 1848. 
MOLLUSCA. 259 

'I'he :Maine forn1 bears a still closer resemblance to the Upper Ludlow Jltfytilus quadratus 

Salter 1 in the subquadrate outline and convexity, but P. bulloides is not quite so tall, and the 

posterior septun1 is a little farther below the dorsal edge. 

The British Anodo?}topsis bulla ~IcCoy, 2 from the Upper Ludlow-Downtonian of ICendal, 

Westmoreland, n1ay possibly prove identical with the Chapman species, but its characters are 

imperfectly lmown. The Irish types of McCoy's species from Galway appear to be n1ore gibbous 

than the Maine shells, with the pallial line more distant from the n1argin, and are described as 

~aving two rounded n1us.cular scara; in the Chapn1an species the muscular scars are elongated. 

Class GASTROPODA. 

Family CAPULIDIE Cuvier. 

Genus PLATYCERAS Conrad. 

In the collections fron1 the Chapman sandstone are fourteen specimens which I refer to 

the genus Platyceras, including a few uncoiled conic shells referable to Hall's genus Orthonychia. The 'last na·med, however, are regarded as of only subgeneric rank, under Platyceras. 

Aside from the imperfect state of preservation and posthumous distortion of the Ch.apman 

specimens, the great irregularity in mode of growth characteristic of most platycerids n1akes 

specific determination very lUlsatisfactory. As is well known, the most frequent cause of 

irregularity in the platycerids results from attachment to or :fL"X:ation upon other objects, and the 

consequent accomn1odation or yielding of the peristome of the gastropod to the inequalities 

of the surface of attachment. 

In all the Chapman specimens here under consideration the shell aperture is irregular in 

forn1, althoug4 the attachment must have been to some other object than a crinoid, for 

crinoids are rare or unknown in the Chapmp,n fauna. 

To the more cp.aracteristic forms of Platyceras are given separate specific names, in accordance with the practice of paleontologists, because of the practical value of this n1ode of designating fossil forn1s, although it is strongly probable that the differences noted are in large 

degree the results of individual or racial deformation in growth rather than specific characters 

associated with heredity. 

PLATYCERAS CHAPMAN! sp. nov. 

Plate ;x:nr, :figureg12, 16. 

cf. 1907. Platyceras kahlebergensis (not Beushausen's sp.). Clarke, New York St~te Mus. Bull. 107, ·p. 185, figs. 

Lower Devonic [Chapman sandstone]: Edmunds Hill, Chapman Township, Aroostook County, Maine. 

Nine specimens from .the Chapman sandstone of Edmunds Hill present several points in 

common and may be regarded as representing a single species. This form has been already 

noted by Clarke under the name Platyceras kahlebergensis Beushausen. . 

The' following characters appear to be distinctive of the Chapman fornu Shell with a sharp, 

slender, apical portion close coiled for the first volution, then rapidly expanding to form a loosecoiled spiral with two volutions. The first volution is nearly regular, and is elevated above. the 

lower whorls; after the completion of one full volution a deep sulcus develops on the outer or 

lower half of the whorl, the upper part remaining gently convex, producing _a sinuate peristome. 

The surface is marked by fine transverse strire and by faint transverse undulations visible near 

the opening. 

The greatest diameter of the largest specin1en is 25 millimeters; at right angles to this 

diruneter the distance across the coils is 16.5 millimeters; the diameter of the periston1e is 

about 15 n1illimeters. 

Loca.Iity: Chapman sandstone, Edmunds Hill (localities 1099 C' and 1099 M), Chapman 

'l'ownship, Aroostook County, l\1aine. 

U. S. National :Museunl;, catalogue Nos. 598.33, 59834. 

1 ~alter, J. W., Great Britain Geol. Survey Mem., vol. 2, pt. I, p, 363, 1848. 2 McCoy, F., British Paleozoic rocks and fossils, p. 271, 1855. 
260 FAUNA OF THE CHAPMAN SANDSTONE OF MAINE. 

Oomparisons.-Clarke regarded this fossil as identical with the Hercynian C'apulus lcahlebergensis Beushausen, 1 but the German fossil is distinguished by having the apical whorl or 

spire much larger and broader proportionately than in the Chapman fossils. The two species 

are, however, closely related. Oapulus crassus Trenkner, also from the Kahleberg, as figured 

by Beushausen, 2 resembles in. some features Platyceras chapmani. The body whorl, however, 

does not becorp.e detached or sulcate. 0.· crassus may be regarded as the regular form of growth 

of a race the irregular form of which-is 0~ lcahlebergen.~is. 

The Maine species P. _ed'mundi and P. chapmani exhibit a sin1ilar relationship to each other, 

and both have the apical whorl more slenderly developed than in the· German types. 

PLATYCERAS EDMUND! sp. nov. 

Plate XIII, figure 19. 

A second species of Platyceras has about the same dimensions and begins growth at the 

apex in the same way, but the sulcus begins to develop near the end of the first volution on the 

upper side of the body of the shell. The sulcus, however, is not deep and toward the front it 

broadens out into two low grooves. The prominent extension of the body of the second volution is along the lower outer side. The resultant form produced is a plane coiled shell in which, 

viewed in such a position that the axis of the spiral stands vertical, the apex is on the same 

horizontal plane with or below the upper rim of the aperture. In P. chapmani the apex is 

elevated 7 millimeters above the upper rim of the aperture. 

The greatest diameter of this shell is 20 millimeters; the peristome is 15 millimeters broad. 

Locality: Chapman sandstone, Edmunds Hill, Chapman Township, Aroostook County, 

Maine. 

U. S. National Museum, catalogue No. 59836. 

PLATYCERAS (ORTHONYCHIA) HEBES Clarke. 

Plate XIII, figure 20. 

1907. Platyceras hebes. Clarke, New York State Mus. Bull. 107, p. 185, figs. 

Lower Devonic: Edmunds Hill, Chapman Plantation, Aroostook County, Maine. 

A third form of Platyceras has been called Platyceras hebes by Clarke, whose description of 

this shell is as follows: 

Shell conical, slightly oblique, apex blunt or minute, surface expanding rapidly with a vertical slope on the posterior and a more broadly curved slope on the anterior side; lower part of the cone obscurely plicated, aperture nearly 

round. 

The figures usually seem to indicate a simple cone, but in realty one side (the anterior~) 

is longer than the other. The post~rior 0) side (right side of fig. 20) of the body of the shell 

is nearly straight and vertical fro_m beak to aperture, but the anterior side is longer and its 

outer surface is broadly curved in an arc measuring about a quarter of a circle from beak to 

peristome, producing a twisted or humpbacked form. On the anterior side of the body the longitudinal plications are twisted The margin of the peristome is sinuous, conforming to the 

irregular sulcations of the surface. 

Locality: Chapman sandstone, west side of Edmunds Hill, Chapman Township, Aroostook 

County, Maine. · 

U .. S. National Museum, catalogue No. 59837. 

Comparisons are given below, under var. [3. 

PLATYCERAS (ORTHONYCHIA) HEBES var. a. 

Plate XIII, figure 26. 

Another specimen referred to this species has a blunt conical form with the broadly rounded 

apex and the flaring body of the type, but shows no plications on the anterior side. The posterior 

1 Beushausen, Louis, Beitriige zur Kenntniss des oberharzer Spiriferensandsteins und seiner Fauna: Abh. geol. Specialkarte Preussen, vol. 6, 

pt. 1, p. 53, pl. 1, fig. 14, 1884. 

2 Idem, pl. 1, fig. 13. 
MOLLUSCA. 261 

side :from tip of beak to margin of lip is 14.5 millimeters long, the peristome is circular and 

16 millimeters in diameter. The surface of the shell is smooth, without either concentric or 

longitudinal folds or striations. · 

Locality: Chapman sandstone, west side of Edmunds Hill, Chapman Township, Aroostook 

County, Maine. . · 

U.S. National Museum, catalogue No. 59838 .. 

Comparisons are given below under var. {i. 

PLATYCERAS (ORTHONYCHIA) HEBES var. {J. 

Plate XIII, figure 14. 

Another short Orthonychia, figured frmn the lateral aspect, appears like a young stage 

of the typical for1n of Orthonychia hebesJ· the apex has the humppacked appearance on the 

posterior side, but the tip is :sharper and is arche~ backward. Below the apex the posterior 

margin is not vertical but is irrclined backward at an angle of about 45°. 

Locality: Chapman sandstone, west side of Edmunds Hill (locality 1099 M), Chapman 

Township, Aroostook County, Maine. 

U. S. National Museum, catalogue No. 59839. 

Allies of Orthonychia hebes and varieties.-Clarke noticed the :resemblance of his Platyceras 

hebes to .Acroculia sp. Oehlert/ from the French Lower Devonian of Angers. In its blunt 

conical shape and obscurely plicated lower half the typical form also resembles two species 

from the Eo-Devonian of Pasterkriffer, near Vellach, in the eastern Alps, mentioned by Frech 2

-

Platyceras protei (Oehlert) and Platyceras sp. Acroculia protei Oehlert, which the typical 

for.m of Platyceras (Orthonychia) hebes resembles very closely in the body of the shell, is a much 

larger species and has a coiled apex; the body of t4e shell expands a little less rapidly than in 

P. (0.) hf}bes. Oehlert's species, which is widely reported in the European Eo-Devonian, was 

originally described in 1883. 3 The species is from Mayenne. 

The variety a, with low, s1nooth, regular cone, devoid of plications, but with bluntly rounded 

erect apex, is similar to· .Acroculia sp. Oehlert, already mentioned, but Oehlert's species is 

much larger. The variety fi is a symmetrical pileopsoid shell with apex arched to the rear and 

with the posterior part of the shell broadly expanded and larger than the anterior part. It is 

similar to some of the forms of the Konieprussian Acroculia subcarinata Barrande, 4 of the 

Bohemian Eo-Devonian, but in the Chapman shell the apex is farther forward. 

PLATYCERA.S (0H,THONYCHIA) AROOSTOOK! sp. nov. 

Plate XIII, :figures 22, 23. 

c£.1859. Platyceras elongat1t1n. Hall, Paleontology of New York, vol. 3, p. 335, pl. 64, :figs. 6, 10; pl. 65, fig. 5. 

Lower Helderberg shaly limestone: Schoharie County, N.Y. 

Shell conical, elongate, nearly straight, with blunt apex, the inner (anterior n side short 

(13 1n.illimetqrs) and the outer side greatly produced (37 millimeters), fon;uing an oval elongate 

aperture 28 by 18 milli1neters :in dimneter. Thebody of the shell is crossed by a few obsolescent 

transverse· undulations and is longitudinally subcarinate along_ the posterior 0) surface. The 

apex is blunt, with a 1ninute, obscurely arched tip. The specimen may have been crushed 

slightly in a way to affect the carination of the body.· 

Locality: Chapn1m1 sandstone, Edn1unds I-IiU, Chapman Township, Aroostook County, 

Maine. 

U.S. Nu,tional Museun1, eatalogue No. 59841. 

Oomparisons.-This species is in general aspect similar to llall's species Platyceras elongatum 

and n1ay possibly prove identical with it, but the Chapman shell is much sn1aller. Hall's speI Oehlert, D. P., Sur le devonien des environs d' Angers: Soc. geol. France Bull., vol. 1 i, pl. 19, fig. 4, 1889. 

2 Frech, Fritz, and Loeschniann, E., Ueber das Devon der Ostalpen; III, Die Fauna des unterdevonischen Riifkalkes, pt. 1: Deutsche geol. 

Gesell. Zeitschr., vol. 4G, pp. 471, 472, pl. 3i; figs. 2, 7, 1894. 

a Soc. g6ol. Fmnce Bull., 3d ser., vol. 11, p. G8, pl. 1G, fig. 1, 1883. 

4 Barmncle, Joachim, SysMme silurien du centre de Ia BoMme, vol. 4, Gasteropodes, pl. 32, figs. 30, 31, 1903. 
262 FAUNA OF THE CHAPMAN SANDSTONE OF MAINE. 

cies has been reported from Devonian OEo-Devonian) rocks in the east slope of ·the Urals,t 

but the Russian shell is a d~fferent species, being arched and having stronger radial ribs. 

PLATYCERAS (ORTHONYCHIA) COMPRESSA sp. nov. 

Plate XIII, figure 24. 

An Orthonychia occurring ·w1th the species just described forms a narrow, bilaterally 

compressed cone, with nearly •straight sides and narrow ovoid aperture. Its length from tip 

of beak to i1mer margin _of lip is 11.5 millimeters and to the outer 1nargin of th~ lip is over 

17 millimeters, but the apertural rim is imperfect. The aperture is· over 14 1nillimeters long 

(incomplete) and 8.5 millimeters wide. 

Locality: Chapman sandstone, Edmunds Hill (localities 1099 :M a,nd 1099 C2), Chapman 

Township, Aroostook County, J\1aine. 

U. S. National Museum, catalogue No. 59840. 

Oomparisons.-In the high, narrow, conoid fonn this species resembles the European J\1id-

. die Devonian Platyceras conoideum (Goldfuss) reported by ·Frech 2 from the eastern Alps, but 

differs in having a nearly straight instead of arched profile. · 

Genus PLATYOSTOMA Conrad, 1842. 

The generic name Diaphorostoma was proposed by Fischer 3 in 1885 ·to supplant Platyostoma Conrad on the ground that Conrad's generic nmne had been preoccupied by Klein (1753) 

for a terrestrial gastropod, by Meigen (1803) for a genus among the Diptera, and by Agassiz 

(1829) for a genus of fish. The name Diaphorost~ma has crept into frequent usage; but as the 

generic name used by Klein, Meigen, and Agassiz was Platystoma, and as Conrad's genus of 

fossil snails is Platyostoma, the name Platyostoma is not strictly preoccupied. Platyost01na 

has indeed been used by Megerle for a molluscan genus now regarded as a synonym of Buccinum; 

but as Megerle's genus was proposed without definition in a manuscript catalogue of shells its 

publication was deficient. · 

The shells of Platyostoma have suffered little deformation, though they were fixed on a 

host organism, like the typical Platycerida. From the latter Platyostoma differs in possessing 

a coiled ·spire; the coils are usua1ly contiguous, and the lip more or less expanded, always so on 

the inner side. Platyostoma differs from Strophostylus in lacking the twisted columella. 

PLATYOSTOMA VENTRICOSU:M Conrad. 

Plate XIIJ, figures ?15, 18. 

1842. Platyostoma ventricosa. Conrad, Acad. Nat. Sci. Philadelphia Jour., vol. 8, p. 275, pl. 17, fig. 5. 

Oriskany sandstone: Schoharie, N.Y. 

1842. Platyostoma arenosa. Conrad, idem, p. 276, pl. 17, fig. 6. 

Helderberg: Catskill, N.Y. 

1859. Platyostoma ventricosa. Hall, Paleontology of New York, vol. 3, p. 300, pl. 55, figs. 9a-d; p. 469, pl. ~12, figs. 

1-10; pl. 113, figs. ·7-8; pl. 115; fig. 8. 

Helderberg shaly limestone: Catskill and Becraft Mountain, N.Y. . 

Oriskany sandstone: Albany, Schoharie, Greene, and Ulster counties and elsewhere in New York; rocks of 

similar age in Maryland and Virginia. 

1859. Platyostoma arenosa Hall, idem, p. 302, pl. 57, figs. 3a, 3b. 

Helderberg shaly limestone: Near Catskill, N. Y. 

1861. Platystoma sp. Billings and Hitchcock, Maine Board Agr. Sixth Ann. Rept., pp. 244-245. 

Oriskany sandstone: Parlin Pond, ~foosehead Lake, Telos Lake, Webster Lake, Seboois River, etc., .northern 

Maine. 

1866. Platyostoma ventricosa (?). Billings, Portland Soc. Nat. Hist. Proc., vol. 1, p. 2, p. 106. 

Oriskany sandstone: Telos Lake, .Maine. 

1 Tschemyschew, T., Die Fauna des unteren Devon am Ostabhange des Urals: Com. ge?l. [St. Petersburg] Mem., vol. 4, No.3, p. 24, pl.l, 

fig. 28, 1893. . 

· 2 Frech, Fritz, Ueber das Devon der Ostalpen, II: Deutsche geol. Gesell. Zeitschr., vol. 43, p. Gi8, pl. 44, figs. 6-60, 1891. 

a Fischer, Paul, Manuel de conchyliologie et de paleontologie conchyliologique, fasc. 8, p. 756, January, 1885. 
MOLLUSCA. 263 

1900. Platyostoma ventricosa ? and sp. Williams, U. S. Geol. Survey Bull. 165, pp. 30, 33. 

Moose River sandstone: Localities cited by Billings, 1861 and1866. 

1905. Platyostoma vmtt1·icosmn. Williams and Kindle, U. S. Geol. Smvey Bull. 244, pp. 32, 39. 

Giles sandstone: 1! miles above Hicksville, Bland County, Va. 

Top of Lewistown limestone: Jackson River, one-half mile below the iron furnace, Covington, Alleghany 

County, Va. 

1908. Diaphorostoma vmttricoswn. Clat·ke, New York State Mus. Mem. 9, p. 149. 

Oriskany: Union Springs, 01·isk:my Falls, Glenerie, Becraft Mountain, N. Y. 

(?)Grande Greve limestone (Ori,skanian): Grande Greve, Gaspe Bay, Quebec. 

A large specimen from Deibroit, :Maine (Pl. XIII, fig. 18), presents s01ne of the characters 

of this species as described and figured by Ilall. The shell is globose, obliquely ovoid; spire 

consisting of three regular contiguous revolutions, the last of which is ventricose and comprises 

the bulk of the shell; Volutions broad-shouldered on the upper side and with excavated sutures. 

The apertm·e is circular or broadly subovate, 28.5 millimeters wide. The total width of the 

body whorl is 30 1nillimeters. The diameter of the shell at the penultimate whorl is about 13.5 

n1illi1ne~ers. The sm·face oniaJmentation comprises strim of growth which in the body whorl 

are aggregated into broad transverse· undulations. The undulations are more pronounced· than 

in New York.shells and are dev·eloped only on the body whorl; this constitutes about the only 

difference between the :Maine shell and the typical forms fr01n the New York Oriskany. A 

s1nall specin1en, showing the first whorl (Pl. XIII, fig. 15), is referred with doubt to the same 

species. 

Locality: :Moose River sandstone between Parlin Poi1d and Detroit (locality 1100A), Somerset County, ~1aine, associated with Spirifer arenosus (Conrad), S. antarcticus ~1orris and Sharpe 

(S. gaspensis Billings or S. hercyni::e Giebel), S. murchisoni Castelnau, Leptocmlia flabellites 

(Conrad), AntispiTifer hm·roldi sp. nov., and other species of the ~1oose River sandstone fauna. 

Plat)TOstonla semns not to occur in the Chapman sandstone fauna. -

. U. S. National ~1useun1, catalogue No. 59842. 

·G!mus STROPHOS~YLUS Hall, 1859. 

STROPHOSTYLUS cf. S. GLOBOSUS Hall. 

Plate XIII, figlll'e 13. 

cf. 1859. Strophostylus r1lobosus Hall. Paleontology of New York, vol. 3, p. 305, pl. 55, fig. 8. 

Helderberg shaly limestone: Catskill and Becraft Mountains, N. Y. 

A naticoid platycerid found in the C~apman sandstone of Edmunds Hill shows the shallow 

canaliculat.e sutures and overhanging upper lip of the aperture prevalent in the species of Strophostylus. It also hus obscure indications of the twisted columella characteristic of Strophostylus, so that the shell is with hardly any question referable to Hall's genus. 

The specimen is globular, with height and breadth of the spire about equal. There are 

three O}' four regular, contiguous whorls, of which the body whorl comprises the bulk of the shell, 

including seven-eighths the height of the spire. The surface is smooth; even the strire of growth 

are discernible only with difficulty, but this faintness of striation may be due to maceration. 

In size and proportions the shell resembles Hall's Str()JJhostylus globosus, from the New York 

I-Ielderberg, but the Chap1nan specimens show fainter strire of growth, the sutures are less deeply 

impressed, and the upper spire is somewhat smaller. There are also minor differences. 

Locality: Chapman sandst011e, west side of Edmunds Hill, Chapman Township, Aroostook 

County, ~1aine. 

Family BELLEROPHONTID...E. . 

· Representatives of three or four distinct types of the Bellerophons have been discovered in 

both the Chap1nan sandstone and the ~1oose River sandstone of Maine. No attempt is n1ade 

here to settle the taxonomic value of the names applied to these types, which will be here adopted 

u.s of generic rank, and the species will be distributed in the genera Patellostium W aagen, Plectonotus Clarke, and Tropidodiscus Meek. 
264 FAUNA OF THE CHAPMAN SANDSTONE OF MAINE. 

Genus PATELLOSTIUM Waagen, 1880. 

The name Phragmostoma flail has been variously applied by authors to different forms of 

Paleqzoic bellerophontoids 1.1ntil its real status has been somewhat obscured by the multitude 

of interpretations given to it. Waagen, De Koninck, Koken, Ulrich and Scofield, Perner, flail 

himself, and Clarke have used tho name in conflicting senses. As an instance of such conflicting 

usage, in 1899 Clarke 1 referred to the supposedly erroneous views of Waagen, De Koninck, etc., 

on Phragmostoma as" quite excusable, but smnewhat out of its proper signification, De Koninck 

even specifying Bellerophon natator Hall as its type,"- but in a later work 2 Clarke himself adopts 

B. natator as the type of the genus. In this second work he gives excellent descriptions and 

illustrations of the forms, which enable us to differentiate to better advantage the terms Phragmostoma I-Iall, Ptomatis Clarke, and Patellostium W aagen~ 

As shown by Clarke, the name Phragmostoma ~as introduced by Hall 3 in 1861, chiefly for 

P. cunulce and P. cymbula, from the Ordovician of the Mississippi Valley, but these two species 

were found to be congeneric with Carinaropsis Hall, 1847. In 1862 Phragmostoma was used 

in a different sense by Iiall 4 for the N eo-Devonian P. natator: from the Cashaqua shale or Intumescens zone of New York, and as this is the only one of the original species of Phragmostoma 

which is generically distinctive. the name Phragmostoma should be, as is generally admitted, 

applied to this type. The structure of Phragmostoma natator Hall and the ~lied P. incisum 

Clarke, as elucidated by Clarke,2 resembles that.of Carinaropsis in the general form of the shell, 

differing chiefly in that the septal plate or diaphragm, which in the carinaropsoids extends from 

the inner lip into the body cavity, does not exist in Phragmostoma, where it is represented only 

by a blunt thickening or callousing of the inner lip, which may become wedge shaped. In Phragmostoma also a distinct slit band, best developed near the mouth, is a conspicuous feature. In 

the carinaropsoids the slit band is represented, when present, by a dorsal carination which 

decreases in intensity on approaching the aperture, and frequently in Carinaropsis the dorsal 

carination is lacking altogether. . 

The generic name Patellostiu:m was conferred by W aagen ~ on the Devonian Bellerophon 

mqcrostomus Roemer, from the Coblenzia.n graywacke at Unkel, as type. This agrees with 

Phragmostoma in lacking the apertural diaphragm of Carinaropsis, but it resembles Carinaropsis 

in lacking the slit band of Phragmostoma. It was originally figured by Roemer 6 as having a 

nonemarginate, circp..lar mouth, but as the lines of growth are broadly insinuated it appears 

quite probable, as intimated by Drevermann, that "the mouth really has a broad sinus anteriorly. 

Posteriorly the mouth has an entire. noncalloused peristome; the inner lip is reflected back like 

a t:rumpet mouth below and is not in contact with the inner whorl. The umbilicus is broad and 

open, exposing the inner whorls, as in Bucania and Trematonotus. 

The genus Ptomatis Clarke was founded on the species Bellerophon patulus Hall, of the New 

York Middle Devonian, which agrees with Patellostium in having the expanded mouth broadly 

emarginate anteriorly and which, like Patellostium, differs from Phragmostoma in lacking a slit 

band on the body whorl. Ptomatis does not, however, possess an entire peristome; the inner 

lip is formed by the preceding whorl, which typically becomes calloused and pappilose.. I doubt 

whether this distinction of the interrupted inner lip in Ptomatis is of more than subgeneric value, 

especially as Roemer's genotype of Patellostium Waagen is but imperfectly understood. In 

Ptomatis, however, the umbilicus is decidedly less open than in Patellostium. It is quite possible that the development of an entire peristome, as suggested by Ulrich and Scofield, may be a· 

fugitive character in the group of shells described under the names Phragmostoma, Patellostium, 

and Ptomatis, giving place to variations displaying the inner whorl as bulging or projecting 

1 Clarke, J. M., The Devonian Mollusca of the State of Para: Mus. nac. Rio de Janeiro Arch., vol. 10, p. 42, 1899 (author's English ed., 1900). 

2 Clarke, J. M., Naples fauna in western New York: New York State Mus. Mem. 6, p. 322, 1903. 

snail, James, New York State Cab. Nat.llist. Fourteenth Ann. Rept., p. 93,1861. 

• llall,James, idem, Fifteenth Ann. Rept., p. 60, 1862 (not pl. 6, figs. 12-14, which show Carinaropsis cymbula). 

~ The.Salt Range fossils; I, The Productus limestone fossils: Paleontologia Indica, 13th ser., p. 131, 1880. 

a Roemer, C. F., Das rheinische U ebergangsgebirge, p. 80, pl. 2, fig. 6, 1844. 
MOLLUSCA. 265 

through the inner lip of the peri.stome or causing the inner lip to become more or less calloused. 

There is 11 great deal of Yariability in the form of the inner lip in many closely allied species and 

·in different stages of the san1e species. 

BELLEROPHON (PATELLOSTIUM) REVOLVENS sp. nov. 

Plate XIV, figures 14, 15, 20, 27. 

A Bellerophon of moderate size, globular or elongate ovoid, with broadly expanded mouth. 

Whorls expanding rapiclly, espeeinlly the last or body whorl; involute, but not very deeply so. 

Umbilicus exposed only in internal molds, where it is small. In all four specimens showing 

the un1bilicus in the internal molds the inner whorls are completely lacking, so that it is impossible to state their number. This absence of the inner whorls in internal 1nolds may be accidental, or it ma.y represent caleification of the apical or inner whorls and hence their total 

romo,'~'al, with the removal of the other calcareous shelly matter. Clean external molds show 

a smaller, very minute un1bilicus, and the inner whorls are covered by the shell of the outer 

whorl and tho expanded lip. In cross section the whorl is broadly reniform, concave in the 

middle of the under side and convexly rounded on the sides and back. The width of cross 

section of the whorl varies from one and three-fourths times the height in the earlier or smaller 

volutions to two or two and one-fourth times the height in the later or larger ·whorls. Aperture laterally and posteriorly broadly expanded like a trumpet mouth, but not expanded 

anteriorly. Outline of aperture broadly suboval; width one and one-half times the length 

of tho mouth, and at the inner lip three times the width of the preceding whorl. Greatest 

width of the aperture at· or very near the midlength. The anterior margin is broadly and 

shnliowly insinuated. Posteriorly the mouth is also expanded and appears to have been spread 

over the preceding whorl, produ(~ing an apparently entire peristome. The inner whorl, howeYer, causes this portion of the aperture to bulge 1nore or less. Two good external molds show 

no trace whateYer of a slit band, a peripheral keel, seam, or otl;I.er band on the surface, the 

back being broadly rounded on the body whorl. One internal mold, however, shows a very 

fnint flnttening or Yery obscure narrow ridge on the dorsum. The surface is ornamented by 

very fine revolving raised lines separated by much broader interspaces. There are three interspn.ces in the width of 1 1nillimeter on the back. Toward the sides and umbilicus the revolYing 

lines becon1e a little more crowded. Commonly in the bQ.ck a very 1nuch fainter raised line is 

developed on the interspace between each pair of lines. The revolving lines seem to die out 

on approaching the broadly expanded apertural portion. No concentric strire of growth have 

been observed, except an obsmue partial wrinkle of growth near the edge of the aperture. 

Internal n1olds are smooth. Shell apparently rather thin. The largest specimen has an apertural width of about 25 n1illimeters and a total length of shell of about 20 millimeters. 

Locality: Common in the ]t.loose RiYer sandstone between Parlin Pond and Detroit 

(locality 1100 A), Somerset County, Maine; associated with the normal marine fauna of the 

Moose River sandstone. 

U. S. National Museum, cata~ogue No. 59843. 

Oompm-isons.-The species is similar to. Bucania freitasi Clarke,t from the Lower Coblenzian fauna of Rio Maecuru, Brazil., but has a relatively smaller spire and the sides of the 

mouth are n1ore nearly symmetrically elliptical. Belleroplwn rhenanus 'Drevermann 2 has, like 

B. freitasi Clarke, n. larger spire, nnd the ornamentation is coarser than in the Maine shell. 

Genus PLECTONOTUS Clarke, 1899. 

The trilobed Bellerophons, represented by the well-known Bellerophon trilobatus Sowerby, 

which hn.ve coJnn1only pt~ssed in revised classifications under the generic nan1e Bucaniella or 

I CIIU'ko, J. 1\L, 'l'ho Devonian Mollusca of the Stn.te of Para: Mus. nac. Rio de Janeiro Arch., vol. 10, p. 35, pl. 3, fig. 22, 1899 (author's English 

od., 1900). 

s Drovormmm, F., Dio l!'auna cler Untercoblenzischichten von Oberstadtfeld bei Daun in cler Eifel: Palaeontograpbica, vol. 49, p. 76, pl. 9, 

figs. o, 7, 1903. 
266 FAUNA OF THE CHAPMAN SANDSTONE OF MAINE. 

Bucanella Meek, have recently been divided by Clarke 1 into two generic groups. Tho en.r·lier 

group includes some min~te Ordovician shells, with Bucaniella nama l\1eek,2 from Crater Falls, 

Colo., as the genot.ype. Meek described the specimens of this genotype as not exhibiting any 

slit band; and in the minute Nco-Ordovician Bucaniella bohem.ica Perner, 3 from the Bohemian 

etu.ges D2 and D5 , the slit band is also recorded as being absent, but~ the specimens are poorly 

preserved. It has also been inferred 4 that the slit band is absent in the likewise minute and 

poorly preserved Bucaniella trilobata (Conrad), from the l\1edina group. 

Ulrich,5 however, states that through the kindness of E. W. Claypole n.nd A. F. Foerste 

he has been enabled to see specimens of B. trilobata (Conrad), which retained ~orne of the shell. 

This he found to be comparatively thick and rriarked externally with very fine revolving lines. 

The lines of growth are very faint, and they form a broad sinus on the central lobes of the 

. beak about as in Protowarthia. There is no slit band. Neither the locality nor the geologic 

formation of specimens examined by Ulrich is indicated, nor is there any intimation whether 

the absence of the slit band in the specimens may be original or is due to poor preservation. 

To judge from the descriptions, the specimens were casts preserving some of the shell substance 

rather than clean external 1nolds.. The newly discovered presence of revolving lines is interesting, especially ill connection with their occurrence in similar Ordovician speciea from the 

Baltic region. . 

The foUowing is a translation of a statement made by Koken: 6 

It is still promulgated that for Bucanin a deep parallel-margined slit and a narrower band, and that for Bucaniella 

a broader, moie angular sinus and lack of a real band, are characteristic. However, the middle of the dorsum in 

Bucanl.ella is elevated, often quite bandlike, but the strioo of growth continue acros.s without deflection. 

A true slit band is developed near the mouth, however, in the Ordovician B. in.flata Koken,7 

and a bandlike elevation is recorded in B. divergens Lin:narssou,8 butin Koken's descriptions 

of the remaining fourteen Bahic Ordovician species of Bucaniella no slit band" or trace of slit 

band is recorded, and in some of the species it is definitely known to be ·absent. It is therefore quite probable that in the minute Ordovician Bucaniella ·nana Meek a slit band is really 

absent, as is commonly supposed; but at the same time it must be emphasized that in Plectonotus 

trilobatus the slit band is faint at best, discernible only on clean, well-preserved external molds, 

frequently not discernible on external molds, and only rarely indicated on sculpture casts or 

internal molds. It is possible, too, that there may be some variability in the persistence or 

nonpersistence of development of the band. At any rate, the term Plectonotus Clarke may 

be used for those forms in which a sli"t band is developed. Clarke's criterion for distinguishing 

the genus 9 is given in his discussion of the genus· Bucaniella Meek; 1870, as follows: 

Bucaniella must be restricted to the seamless, broad-backed trilobatus (Conrad) group. For the broad trilobed 

species having a seam I am compelled to introduce a new name, Plectonotus, as the presence or absence of this feature 

is certainly· a matter of considerable taxonomic importance. 

BELLEROPHON (PLECTONOTUS) TRILOBATUS Sowerby. 

Plate XIV, fi~es 1, 1a, 1b, 12, 13, 17, 18, 19, 28. 

It. is not certain whether or not all the specimens cited as Bellerophon trilobatus Sowerby 

are to be regarded as synonymous with the species described by Sowerby. Doubt was expressed 

by Sowerby 10 in the original description of the species as to the identity of the typical form 

from Felindre with the older Silurian form. He said: "Loc. Felindre. Is the 'same species 

in the Caradoc [May Hill~] sandstone at Eastnor Park; northeast of Gaerfawr, Prescoed Common; and Michael wood Chace, Tortworth ~" 

t Clarke, J. M., The Devonian Mollusca of the State of Para: Mus. nac. Rio de Janeiro Arch., vol. 10, pp. 36-39, pl. 3, 1899 (author's English ed., 

1900). 

2 Meek, F. B., A preliminary list of fossils collected by Dr. Hayden in Colorado, New Mexico, and California, with a brief description of a few 

of the new species: Am. Philos. Soc. Proc., vol. 11, p. 426, 1870. 

a Perner, Jaroslav, Systelme silurien du centre de la Boh~me, pt. 1, vol. 4, Gasteropodes, tome 1, p. 66, pl. 86, figs. 40-42, 1903. 

4 Clarke, J. M., op. cit., p. 36. ' 

5 Ulriqh, E. 0., and Scofield, W. H., The Lower Silurian Gastropoda of Minnesota: Geology of Minnesota, vol. 3, Paleontology, pt. 2, p. 848, 1897. 

o Koken, Ernst, Leitfossilien, p. 392, 1896. 

7 Koken, Ernst, Die Gastropoden des baltischen Untersilurs: Acad. imp. sci. St.-Peters bourg Bull., 5th ser., vol. 7, No.2, p.127, September, 1897. 

s Idem, p. 128. 

o Clarke, J. M., op. cit., p. 37. 

10 Powerby, J. C., in Murchison, R.I., The Silurian system, pt. 2, p. 604, 1839. 

/, 
MOLLUSCA. 267 

Phillips indicated tlll'ee varieties of the species~a, from Baggy Point; b, ·from Meadsfoot 

Sands; and c, from South Pethenvin~pointing out slight differences in form; at the same time 

he associated with var. a the speeimens from Felindre,·Baggy Point, and Eastnor Park, the last 

being in Cai.·adoc [May I-Iill ~] sands~one. It is highly in1probable that the :May Hill and Devonian species are i~eutical; nmrertheless the characters described nutke it difficult to separate 

thmu. The species fron1 Felindxe is supposed to be the typical form, but the following references to the species should be n1ade as indicating what have been regarded by authors 'as 

synonyn1ous: 

?1838. Planorbis trilobatus. Comad, New York Geol. Smvey Second Ann. Rept., p. 113; name only [possibly a 

Bucaniella]. 

Fourth group of "Saliferous sandrock" of Eaton: Medina, N.Y. 

?1839. Planorbis trilobatus. Conrad, New York Geof. Survey Third Ann. Rept., p. G5. 

No formation or locality given. 

1839. Bellerophon trilobat'us. Sowerby, in Murchison's Silurian system, pt. 2, p. G04, pl. 3, fig. 16 (type). 

Old Reel sandstone (lowest beds): Felindre. 

?Not Caradoc sandstone·: Eastnor Park, etc. (p. 643, pl. 21, fig. 21 (pars), =Bucaniella?). 

1840. BellerOJ)lwn trilobat1ts. D'Orbigny, Histoire naturelle des Cephalopoda, p. 209, pl. 7, figs. 24-27; pl. 8, fig. 13. 

No formation or locality cited. · · 

1841. Bellerophon trilobat1ts. Phillips, Paleozoic fossils of Cornwall, p. 107, pl. 40, fig. 200. 

Var. a is reported to occur in North Devon, at Baggy Point, in llmestone and in other districts; at Felinclre, in 

tho lower part of the Old Reel sandstone, and at Eastnor Park, in Caradoc sandstone, etc. Var. b has been 

found only at Meadsfoot Sands, near Torquay. Var. cat South Petherwin, in Cornwall. 

?1843. Bellerophon trilobatv.s. Hall, New York Geol. S1.lfvey Rept. Fourth Dist., p. 48, figs. 6, 7 (?Bucauiella]. 

Gray sandstone: Medina and Lockport, N. Y. 

1843. Bellerophon bisulcatus. Roemer, Versteinerungen des Harzgebirges, p. 32, pl. 12, fig. 30. 

Hercynian: Kahleberg, in the Harz. · 

1850. BelleroJ)hon trilobatus. ])'Orbigny, Prodrome de pah~outologie, vol. 1, p. 31. 

. No formation or locality cited. 

?1852. B1wania trilobatus. Hall, Paleontology of New York, vol. 2, p. 13, pl. 4, figs. 5a, b; 3d (?Bucauiella]. 

Medina sandstone: Medina, N. Y. 

?1852. Bucania trilobata. Hall, idem, p. 93, pl. 28, fig. 10. 

Clinton: Near Blackstone's and Wadsworth's quarries; New Hartford, Oneida County, N.Y. 

1855. Bellerophon trilobatus. Sedgwick and McCoy, British Paleozoic rocks and fossils, p. 311. 

Tilestones: Storm Hill, Llandeilo, Caermarthenshire. · 

185G. Bellerophon trilobatus var. tum1:dus. Sandberger, Die Versteinerungen des rheinischen Schichtensystems, in 

Nassau, p. 177, pl. 22, fig. 1. 

Spirifer sandstone: Niederlahnstein, Fachingen near Diez, Atteupauseu near Holzappel, Nassau; Kahleberg 

in the Harz; Laubach ·and Winningen near Coblenz; Meadsfoot Sands and Baggy Point, Devonshire; South 

Petherwin, Cornwall. 

Pterinea shales: Singhofen, Nassau. 

185G. BelleroJ)lwn (Euphemus) quadrilobatus. Salter, Geol. :Soc. London Mem., 2cl ser., vol. 7, p. 214, figs. 1, 2. 

Devonian (?): 'Varm Bokkeveld, South Africa. 

?1858. Bttcania trilobatus. Rogers, Geology of Pennsylvania, vol. 2, pt. 2, p. 822, fig. 624.· 

Levant uppermost sandstones: "Long Narrows," below Lewistown, Pa. 

1868. Bellerophon trilobatus. Bigsby, Thesaurus siluricus, p. 145. 

?Not Ordovician: Portugal (Broun). 

?Middle Silurian: Southwest Scotland, Malvern; Shropshire; ~1arlee,s Bay, Llanrwst, Wales; Galway, Tonlegee, Ireland. 

Upper Silurian: Lammermim, southwest Scotland·; Storm Hill, Plas Madoc, Llamgadock, Felindre, etc .. 

Wales, and Shelve, Shropshire. 

1868. Bucania trilobita. Dawson, Acadian geology, pp. 498, 569, 605. 

Upper Arisaig or newest Silurian: East River, Pictou, Nova Scotia. 

Upper Silurian [Arisaig beds]: Arisaig; Nova Scotia. 

,Nictau coarse limestone (loose), below the Oriskany ferriferous beds: Nictau, Nova Scotia. 

1873. Bcllerophon trilobatus. Salter, Catalogue of Cambridge Museum, pp. 97, 192. 

1879. Bttcania trilobatus. Derby, Mus. nac. Rio de Janeiro Arch., vol. 2, p. 92. 

1879. Bucania trilobata. Derby, Am. Philos. Soc. Proc., vol. 28, p. 168. 

1884. Bellerophon trilobatus. Lindstrom, Silurian Gastropoda and Pteropoda of Gotland, .pp. 18, 19, 80, pl. 4, figs. 

13-15. 

Wenlock shales: Wisby and Hablingbo, Gotland. 

N eo-Silurian oolite and sandstone: ~ursvick, Gotland. 
268 FAUNA OF THE CHAPMAN SANDSTONE OF MAINE. 

1884. Bellerophon tumidus. Beushausen, Abh. geol. Specialkarte Preussen, vol. 6, pt. 1, p. 44. 

Haupt-Spirifer sandstone: Kahleberg, Schalk, Bocksberg, etc., in the Harz Mountains. 

1889. Bellerophon tumidus. Fr. Sandberger, Nassauischer Verein Naturkunde'Jahrb., Jahrg. 42, pp. 13, 25. 

cf. 1890. Bellerophon sp. Derby, Mus. nac. Rio de Janeiro Arch., vol. 9, p. 77. 

Devonian: Chapada, 30 miles northeast of Cuyaba, Matto Grosso, Brazil. 

1892. Bellerophon sp. indet. Ulrich, Neues Jahrb., Beilage Band 8, p~ 41. 

Eo-Devonian, Conularia beds: Between Oconi.and Pulquina, Bolivia. 

1895. Bellerophon tumidus. Kayser, Soc. geol. Belgique Annales, vol. 22, p. 182, pl. 4, figs. 7, 8 (not 5, 6). 

Upper Coblenzian: Pepinster, Belgium. 

1899. Bellerophon trilobatus. Peach and Horne, The Silurian rocks of Britain, vol. 1, Scotland, pp. 681, 714. 

Not Ordovician: Sot1th Scotland (pp. 681, 696). 

Wenlock-Ludlow beds: Kirkcudbright, Riccarton, etc., South Scotland. 

?1899-1900. Bucaniella trilobata var. viramundo. Clarke, Mus. nac. Rio de Janeiro Arch., vol. 10, pl. 2, figs .. 20-22, 

1899 (author's English ed., p. 18, 1900).1 

Silurian: Rio Trombetas, Para, Brazil. 

1899-1900. Bucaniella reissi. Clarke, idem, p. 37, pl. 3, figs. 7, 8, 9. 

Eo-Devonian: Rio Maecuru, Para, Brazil. 

1899-1900. Plectonotus? salteri. Clarke, idem, p. 39, pl. 3, figs. 12, 13.2 

Eo-Devonian: Rio Maecuru, Para, Brazil. 

1899-1900. Plectonotus derbyi. Clarke, idem, p. 38, pl. 3, figs.-14-18. 3 

Eo-Devonian: Rio Maecuru, Para, Brazil. 

1902. Bellerophon? (Bucanella?) tumidus. Drevermann, Palaeontographica, vol. 49, p. 77. 

Lower Coblenzian: Oberstadtfeld, near Daun, in the Eifel. 

1903. Bucaniella reissi. Katzer, Geologie des Unteren Amazonasgebietes, p. 198, pl. 12, fig. 11. 

1903. Plectonotus? salteri. Katzer, idem, p. 198, pl. 12, fig. 10. 

Eo-Devonian: Rio Maecuru; Para, Brazil. 

1904. Bellerophon quadrilobatus Salter. Reed, South African Mus. Annals, vol. 4, pt. 6, p. 242. 

[Eo-Devonian]: Warm Bokkevel<;l, South Africa. · 

1904. Bellerophon (Bucaniella) aff. B. trilobatus (Sowerby). Reed, idem, p. 242, pl. 30, :fig. 5. 

[Eo-Devonian]: Gydo Pass, South Africa. 

1904. Bellerophon (Bucaniella) cf. B. reissi. Reed, idem, p. 243, pl. 30, fig. 6. 

[Eo-Devonianj: Road cut, north of vVhupperthal, South Africa. 

1904. Bellerophon (Plectonotus) aff. B. salteri Clarke. Reed, idem, p. 243, pl. 30, fig. 7. 

[Eo-Devonian]: Road cut north of Whupperthal, South Africa. 

1906. Bellerophon reissi Schwartz, Albany Museum Rec., vol. 1, pt. 6, p. 402, pl. 8, fig. 1. 

Bokkeveld beds: Warm Bokkevelcl, Ceres, Cape Colony. 

1906. Bellerophon trilobat'us. Schwartz, idem, p. 403, pl. 8, fig. 2.4 

Bokkeveld beds: Warm Bokkevelcl, Ceres, Cape Colony. 

1907. Bellerophon (Plectonotus?) gaspensis. Clarkc;J, New York State Mus. Bull. 107, p. 194, figs. 

Lower Devonic: Grande. Greve, Quebec. 

Shell globular, symmetrically plane coiled, whorls between 2~ and 3!, rapidly and regularly 

expanding, the body whorl composing the visible bulk of the shell. The apical whorls are 

1ninute inclosed an~ hidden within the body whorl. The back is trilobed; there is a broad 

median convex saddle with a shallow but distinct furrow on each side serving to demarcate a 

lateral wing on the outer side. These two furrows are always distinctly and smnetimes strongly 

developed, though they are variable in different individuals. -They increase in "\vidth and 

usually in depth with age and are visible in the youngest specin1ens. The median lobe is particularly variable in convexity. Occasionally the 1nedian lobe is strongly convex or inflated,· 

but in most specimens it is depressed-convex along the center. On the median lobe of some 

specilnens, for a portion of the whole of the body whorl there are developed two faint parallel 

1ninor grooves which divide the median lobe into three obscure, nearly equal strips. The central 

strip apparently bears the slit band or represents it and is more conspicuous on the internal 

molcls than on the exterior. The lateral lobes of the shell expand in width gradually frotn the 

earlier ·whorls and rapidly on the last half of the body whorl. In dorsal aspect they are usually 

about half the width of the median. lobe. Sculpture casts and internal n1olds show a large, 

1 In this species the medium lobe is a little smaller, relatively, than usual. 

~ As is shown by Clarke's fig. 12, the apertural sinus in this form is much shallower than in the Maine forms. 

a As illustrated in Clarke's fig. 1 i, the inner end of the apertural sinus is more pointed and angular than in the Maine forms, where the margins 

are nearly parallel some distance below the end. 

4 'fhis form diiiers from the preceding in exposing more of the inner whorls. There is variability in this respect among the Maine fossils, which 

is increased by differences in preservation. · 
MOLLUSCA. 269 

well-de:fined, deep u1nbilicus, but this is nearly filled by the thickness of the shell and the lateral 

expansions of the mouth, so tha,t the u1nbilicus is really narrower, though fairly deep and broad. 

The aperture is slightly expanded, and the peristome, in well-preserved specimens, shows a 

deep triangular sinus, which cuts into the margin of the aperture for a distance equal to the width 

of the median lobe. The edge of the lip is turned slightly outward at the extreme apex of the 

sinus, though the periston1e in general does not flare at the edge. Two faint grooves are occasionally seen on the n1edian lobe arising fron1 the sides of the inner end of the sinus, inclosing 

a narrow flattened 1nedial band which n1ay represent the slit band,. but this band is very indistinct and in specimens that show it best affects only the outer third of the last whorl. Outside 

and inside molds are generally quite smooth; but exceptionally clean 1nolds of the exterior 

show very faint regular lines of growth, closely crowded, about si.x or seven to the millimeter. 

The dimensions of one of the largest and best preserved specimens are, width of aperture from side 

to side, 16.5 n1illimeters; diameter of last whorl fron1 center of lip to opposite side of whorl, 

17 1nillimeters; width of body of whorl one-half revolution back frmn lip, 7.5 millimeters; 

depth of sulcus from outer edge of lip, 8.5 millimeters; width of central lobe ~t edge of lip, 10 

millimeters. The smallest individual has a length of 7 millimeters. The average length of 

the specimens is 12 to 14 milliuaeters. · · 

Locality: This is one of the very few species common to both the Chapman and the Moose 

River sandstones, in both of which it is fairly abundant. In the Chapman the.species is cqmmon 

in the sandstones west of Presque Isle Stream (locality 1099 J) and also occurs in loose bowlders 

in Edmunds I-Iill (localities 109£1 C, 1099 K). In the Moose River sandstone at Detroit, Somerset 

County, the species is also fairly abundant. In size, outline, convexity, relative development . 

of lobes, apertural sinus, slit band, and ornamentation I have not been able to distinguish the 

for1ns frotn the two horizons. 

U. S. National }.{useum, catalogue Nos. 59843 to 59847. 

Oomparisons.-In the synonymy of P. trilobatus are. included for1ns which are called by 

different names but which in size, outline, convexity, relative development of lobes, etc., do 

not depart from the specific type. As for the more precise details of the apertural sinus and the 

presence and strength of the revolving lines, which have been shown by Koken to be ilnportant 

specific characters in the species of Bucanella, too little is known of the forms cited above to· 

warrant separating thmn at present. The species, or at .least this specific type, has a long 

range in time and is widespread in areal extent. 

Genus TROPIDO:piSCUS Meek, 1866. 

In the Ordovician, SiluTian, Devonian, and Carboniferous, and particularly~ certain horizons 

of the upper part of the Silurian and the Lower Devonian appear some laterally compressed, 

lenticular, keeled, deeply involute Bellerophons without slit band, in which the aperture is 

not expanded and which are marked on the surface by concentric lines of growth. For such 

shells the generic name Tropidiscus (type Bellerophon curvilineatus Conrad,I E9-Devonian) 

was proposed by Meek 2 in 18()6, but as the name Tropidiscus was preoccupied, Meek shortly 

afterward changed it to Tropidodiscus 3 and included in the genus a second species, the Mississippian (Kinderhook) from B. cyrtolites I-Iall. · 

In 1.S82 and 1883 De Koninck, 4 recognizing the preoccupancy of Tropidiscus but apparently neglecting the corrected name Tropidodiscus Meek, proposed the new tern1 Tropidocyclus 

(type B. curvilineatus Conrad):, including in the genus two or three new species from the lower 

Mississippian (Tournaisian) and higher Carboniferous limestone (assises VI) of Belgium. In 

discussing these forms in 1899 Clarke 5 proposed that the name Tropidocyclus De Koninck be 

1 Sec Hall, James, Paleontology of Now York, vol. 5, pt. 2, p. 94, pl. 22, figs. 1-6, 1879. 

2 Mock, F. 13., Chicago Acad. Sci. Proc., voL 1, p. 9, 1866. 

sMock, 1!~. B., lllinois Geol. Survey, Paleon.tology, vol. 1, p. 160, 1866. 

4 De Koninck, L. G., Notice sur la fo.millo des Beller?phontidre suivie de la description d'un nouveau genre de cette famille (Waagenia): Soc. 

gool. Bolgiquo Mom., vol. 9, p. 83, 1882; Faune du calcaire carbonifere de Ia Belgique, pt. 4, Gastoropodes: M:us. roy. bist. nat. Belgique Annales, 

vol. 8, pp. 123, 160, pis. 42 bis, 43 (pars), 1883. 

G Clarke, J. 1\L, Tho Paleozoic fawms of Pam, Brazil; Devonian Mollusca: M:us. no.c. Rio de Janeiro Arch., vol. 10, pl. 3, figs. 10, 11,1899 (author's 

English od., pp. 39-40, 1900). 
270 FAUNA OF THE CHAPMAN SANDSTONE OF MAINE. 

restricted to the Carboniferous forms characterized by "their lateral appression, narrow dorsum, 

small umbilicus, and conspicuously, the character of their ornamentation," such as T. rotula 

and T. gratiosus, and including B. cyrtolites Hall, and that the name Tropidodiscus Conrad be 

restricted to cover such forms as B. curvilineatus Conrad, in which t4e shell is" lentiform, sharply 

keeled, and deeply involute, without expanded aperture or peripheral seam, and with rather 

coarse concentric growth wrinkles." Koken's name Oxydiscus 1 (type 0. imitator· Koken; 

Meso~Devonian) has been applied by European authors 2 to similarly compressed keeled shells, 

iden'tical with the Tropidodiscus of Meek as amended by Clarke. In the Ordovician species 

included by Koken 3 in Oxydiscus the whorls are not involute, and the shells hence differ from 

typical Oxydiscus. 

For shells of similar form which display revolving lines or ornamentation, Perner 4 proposed 

the name Cyrtodiscus; .but it is questionable whether on this ground alone Perner's genus is 

valid. 

Koken's genus Temnodiscus superficially resembles the group of Tropidocyclus De Koninck, 

as amended by Clarke, but it is described in Koken's "Leitfossilien" as having a distmct slit 

band. In 1897, however, Koken 5 stated that no slit band occurs in Temnodiscus, and he was 

followed in his assertion by Perner, 6 who made the distinction between Temnodiscus ancl Oxydiscus [Tropidodiscus]'lie in the more rapid expansion of the body whorl in Temnodiscus. 

I.have adopted the term Tropidodiscus in the sense evidently intended by 1\1eek in 1866, in 

using the species Bellerophon curvilineatus Hall as type, and regard the name Oxydiscus Koken, 

1896, as a synonym; Temnodiscus Koken, 1897, and Cyrtodiscus Perner, 1903, are held to be 

either synonymous with or subordinate to Tropidodiscus Meek. 

TRoPmonrscus OBEX Clarke. 7 

Plate XIV, figures 3-10, 16, 21. 

?1839. Bellerophon carinatus: Sowerby, in Murchison's Silurian system, p! 604, pl. 3, fig5. 1d., 4. 

Lowest "Old Red sandstone" or "Passage beds": Horeb Chapel, Caermarthenshire. 

1900. Bellerophon carinatus. Williams, U. S. Geol. Survey Bull. 165, pp. 85, 86. 

Chapman sandstone: Edmunds Rlll, Chapman, Malne. 

1907. Tropidodiscus obex. Clarke, New York State Mus. Bull. 107, p. 193, figs. 

Lower Devonlc: Edmunds Hill, Chapman Township, Maine. 

Shell a lenticular disk, whorls 3 to 3!, expanding with n1oderate rapidity; deeply involute, 

. embracing more than half the inner whorl. Umbilicus of moderate width, depth, two-thirds. 

the width or slightly more, bounded by a rounded ridge. An external mold of the umbilicus 

of the right side resembles a little turbinate gastropod, while that of the left side might be easily 

mistaken for a little sinistral gastropod like Cliospira~ The internal whorls are exposed to good 

advantage only in very clean interi1al1nolds.. The distance from the inner lip across the apex 

to the opposite, inner suture of the body whorl is equal to about two-thirds the distance from 

the inner suture continued to the dorsal edge opposite the mouth. There appears to be no 

callosity on the inner lip. In cross section the whorl is compressed,.approximately an equilateral triangle; dorsum subangular, with lateral profiles mostly ~onvex to the umbilical ridge. 

In this distance is included an angle of about 60°, or very slightly over 60°. On the clean inter1 Koken, Ernst, Entwickelung der Gastropoden von Cambrium bis zur Trias:. Neues Jahrb., Beilage Band, vol. 6, p. 390, 1885; Die Leitfossilien, 

p. 100 (not p. 393), 1896. 

2 Frech, Fritz, and Loeschmann; E., Ueber das Devon der Ostalpen; III, Die Fauna des unterdevonischen Rifikalkes, 1: Deutsch. geol. 

Gesell. Zeitschr., vol. 46, p. 463, pl. 34, figs. 2a-2c, 1894 (0. geyeri Frech; 0. delanovi Oehlert). Tschernyschew, T., Die Fauna des unteren Devon_ 

am Ostabhange des Urals: Com. geol. Mem., vol. 4, No.3, pp. 29, 160, pl. 3, fig. 2, 1893 (0. minimus Tschernyschew; not the other species here cited 

under Oxydiscus). · 

a Koken, Ernst, Die Gastropoden des baltischen Untersilurs: Acad. imp. sci. St.-Petersbourg Bull., 5th ser., vol. 7, No.2, pp. 13Q-131, September, 1897. 

4 Pirner, Jaroslav, Syst~me silurien du centre de la Boh~me, pt. 1, vol. 4, Gasteropodes, tome 1, p. 74, 1903. 

5 Koken, Ernst, Die Gastropoden d~s baltischen Untersilurs: Acad. imp. scL St.-Petersbourg Bull., 5th ser., vol. 7, No.2, p. 129, 1897. 

a Perner, Jaroslav, op. cit., p. 75. ' 

· 2 In the preparation of this report the specimens here listed were referred to Sowerby's species Bellerophon carinatus. As, however, before the, 

report was·ready for publication Clarke proposed the name obex for specimens derived from the same locality, undoubtedly the same fonns, I have 

adopted his name as applicable, although there appear to be no constant differences by which the Maine shells can be distinguished from the specimens to which Sowerby's name is applied in Great Britain. 
MOLLUSCA. 271 

nal1nold there is a slight concavity in the profile just below the dorsum. In the imperfect casts 

which represent the usual aspect of the species in the Chapman sandstone the profile is comnlonly convex from clorSUlll to umbilic'al ridge; in a few specimens, however, an exceedingly· 

faint constriction of semiconcavity is develope~ either midway down the side or shortly above 

the umbilical ridge, causing the ridge to bulge more pronouncedly. 

From the rounded un1bilical ridge the profile in transverse section slopes inward and downward 011 the ventral side of the whorl in a concave or sigmoidal line to the suture. Between the 

sutures the ventral side of the whorl is arched up by the dorsum of the preceding whorl into a 

deep groove, semicircular in seetion and equal in width to one-fourth the width of the whorl. 

No revolving lines have been observed in this groove. The height ofthe whorl in cross section is 1-! tin1es the width (in clean internal mold). The mouth is only slightly, if at all, longer . 

than wide and is not expanded. A slight apertural sinus is developed. There is no slit band 

on the dorsum. In one specim.en a narrow impressed striation revolves part way along one 

side. of the dorsum, but this may be clue to crushing. 

In two well-preserved fragments the surface is covered with fine raised lines of growth, 

barely visible to the naked eye, separated by interspaces of equal width; there are about five of 

these lines in· the space of 1 Inillimeter. The lines of growth sweep back. in a broad curve· 

approaching the dorsum; ventrally they. die o.ut just within the umbilical ridge. There is no 

ornmnentation in the umbilicus. In a small fragment showing an exceptionally well preserved 

n1olcl of the external surface (Pl. XIV, fig. 3) very fine revolving lines, finer than the lines of 

growth and cancellating them, are observable with a magnifying glass. Internal molds and 

the common sculpture casts are smooth. 

A large individual has a length of 26.5 millimeters, a height of 15 millimeters, and a width 

of 10.5 1nillimeters: Some other speciinens have the following din1eusions · 

D·imensions of specimens of Tropidodiscus obex. 

(mi 

Length Height Width 

llimeters). (millimeters). (millimeters). 

20.5 . 17.5 8.75 

20. 75 16 10 

13.66 10 5 

Some of this variability appears to be clue to distortion by pressure in the rock. 

Locality: Abundant in the Chapman sandstone, Edmunds Hill (localities 10991\1, 1099. C), 

Chapman Township, Aroostook County, Maine .. The same form seems to occur also in the 

Moose River sandstone at De~Groit and Parlin Pond, Somerset County, Maine, accompanying 

'the species T. somerseti, described below. 

U.S. National Museum, catalogue Nos. 59848 to 59851. 

81Jecific relations.---This shell is very similar to Bellero1Jhon (Oyrtodiscus) compressus Sandberger/ from the basal Meso-Devonian Wissenbach shales, but T. obex is more deeply involute 

and its ventral profile within the umbilical ridge is sigmoidally concave, instead of convex. 

The ventral gi·oove in the base of the whorl is deeper in the Chapman fossil and lacks the four 

funows developed in the Germ.an form. 

TROPIDODISCUS (TEM:NODISCUS) SOMERSET! sp. nov. 

Plate XIV, figure 22. 

In the Moose River sandstone at. Detroit', Somerset County, Maine, occur a few specimens 

of a Tropidodiscus which at first glance appears to be. identical with the Chapman T. obex. 

Close examination, however, shows the Detroit specimens to be slightly narrower; the body 

whorl expands a trifle more rapidly than in the Chapman species, and the umbilicus appears to 

1 SLUldbergor, Guido und Fridolin, Die Versteinerw1gen des rheinischen Schichtensystems in Nassau, p. 180, pl. 22, figs. 6-6f, 1856. 
272 FAUNA OF THE CHAPMAN SANDSTONE OF MAINE. 

be somewhat broader. These characters will serve to distinguish the species. Only faint 

growth lines have been observed. Specimens showing the revolving lines, if indeed these exist, 

have not yet been found. 

Locality: Moose River sandstone, Detroit, Somerset County, Maine. 

U.S. National Museum, catalogue No. 59852. 

Oomparisons.~Shells of the type of T. somerseti are widespread in the Eo-Devonian and 

Meso-Devonian of Bolivia, Argentina, Brazil, and South Africa, where they are usually identified 

with Bellerophon [ Temnodiscus] gillettianus Hartt and Rathbun. The o~iginals of T. gillettianus 

from the Meso-Devonian fauna of Erere, Para,- Brazil, differ from Tropidodiscus somerseti in 

having a broader dorsum, three-quarters of a whorl less, and the whorls less deeply involute_.l 

Tropidodiscus ( Temnodiscus) somerseti bears a close resemblance also to figures of the Bohemian 

Ordovician Sinuitopsis neglecta (Barrande) var. transgrediens Perner, 2 but the Maine shell has a 

narrower dorsum and half a whorl more, and the whorls are more deeply involute than in the 

Bohemian Ordovician shell. 

TROPIDODISCUS l\UNIMUS var. AMERICANUS Var. nov. 

Plate XIV, figures 2, 11. 

?1893. Oxydiscus minimus. Tschernyschew, Com. geol. Mem., vol. 4, .No.3, p. 160, pl. 3, fig. 4. 

Eo-Devonian: Smelting pool, 4 versts northeast of the Bogosslowsk mines, eastern Ural Mountains. 

A single specimen from the Chapman sandstone agrees in its extreme compression, general 

outline, convexity, number and depth of whorls, umbilicus, and ornamentation with Tschernyschew's description and figure of Oxydiscus minimus, from the Eo-Devonian of the eastern Ural 

Mountains. It is, however, about" twice as large as that species. Tschernyschew compared 

his Oxydiscus minimus with Oxydiscus orbiculus (Lindstrom), distinguishing the two by the lesser 

involution of the whorls in 0. orbiculus. Lindstrom's species has two whorls more than t!J_e 

Chapman species, and if 0. minimus has the same large number of whorls as Lindstrom's species, 

it is quite distinct from the Chapman fossil. The figures do not indicate this, however, and the 

Maine specimen is referred to a variety of the Russian species with the following characters: 

Shell small, very much compressed, "discoid, symmetrically plane coiled, whorls between 

21 and 3i, expanding with moderate rapidity;· deeply involute, inclosing about half or more of 

the preceding whorl when the shell is preserved, but apparently much less involute when the 

shell substance is removed .. Umbilicus broad, open, deep, bounded by a rounded ridge. In 

cross section the whorl is very much·compressed, with sharply carinated narrow keel, on each 

side of whi~h the profile is concave for a short distance, then becoming convex as far· as the 

rounded umbilicus ridge. In this distance is included an angle of less than 60°. The profile then 

bends inward, and on the ventral side the whorl is deeply-excavated by the preceding revolution. 

The height of the whorl is equal to aboutone and eight-tenths times the width. The mouth is 

longer than wide, is not appreciably expanded (note cross section of the whorl), and is characterized b37 a very deep A-shaped sinus. This sinus extenf].s nearly one-fifth of tbe revolution, 

and the close subparallel edges at the upper end give it the appearance of a typical Bellerophon 

or Emarginula slit. No true slit band is demarkable on the dorsum. The whorl on the inner 

side of the mouth, appears to have been covered with a m~mbranous expansion of the peristome, 

though this conclusion may be· erroneous. 

The surface is cov~red with exceedingly fine, concentric lines of growth, which arch slightly 

backward over the sides of the whorl and very far backward on the dorsal keel, where they 

become nearly parallel to the dorsal edge of the shell. These lines are very faint, being barely 

visible under a hand lens. 

Length, 10.7 millimeters; height, 10 millimeters; width, 4 millimeters . 

. Locality: Chapman sandstone, west of Presque Isle Stream (locality 1099 J), Chapman 

Township, Aroostook County, Maine. 

U .. S. National Museum, catalogue No .. 59853. 

1 See Clarke, J. M., The Devonian Mollusca of the State of Para: Mus. ~ac. Rio de Janeiro Arch., vol. 10, p. 40, pl. 3, figs. 1Q-ll, 1899 (author's 

English ed., 1900). 

s Pemer, Jaroslav, op. cit., p. 71, text figs. 45-47, pl. 88, figs. 33, 35, and 37. 
MOLLUSCA. 273 

Fn,mily PLEUROTOMARIID.tE D'Orbigny. 

No representatives of the genus Pleurotomaria De France or of its multitudinous subgenera, 

which are so widespread in Paleozoic faunas, have been recognized up to the present time in 

the Chapman fauna. The fonn listed as PleurotOinaria sp. in the preliminary catalogue of the 

Chapman species 1 belongs to Perner's genus Pseudotectus; Clarke also n1istook the same shell 

for a Pleurotomaria, referring it to the genus or subgenus Eotomaria. 

Several species present in the Chapn1an fauna, however, are referable to several of the 

groups of the old genus ~1urchisonia of authors. 

Gfenus "MURCHISONIA" of autcors. 

Genus MESOC<ELIA Perner, 1907. 

Mesocmlia was proposed by Perner 2 as a subgenus of Murchisonia and includes an easily 

recogni~ed, characteristic type of shell distinguished by the exceedingly terrete spire, with a 

n1inin1un1 number of 13 to 20 or n1ore whorls. Owing to the slenderness of the spire, the entire 

spire is only rarely preserved; hence the total number of whorls is rarely apparent. Mesocmlia 

differs fron1 Cmlocaulus Oehlert ( = Cmlidiun1 Clarke and Ruedmnann), Ptychocaulus Perner, 

Turriton1a Uh·ich and Scofield, Catozone Perner, and sin1ilar exceedingly terrete murchisonoid 

shells by having the whorls cylindrically rounded and·widest near the 1niddle, with more deeply 

excavated sutures; moreover, the slit band is very faint, frequently not discernible, and is 

situated on the n1iddle of the whorls, instead of near the suture. A few whorls, especially in 

senile shells of Mesocmlia, commonly show an obscure angulation on the periphery, less pronounced than in Goniostropha and not at all persistent. From the somewhat similar roundwhorled I-Iormotoma Salter M:esocmlia is easily distinguished by its slender, terrete spire and 

more numerous and narrower whorls. 

Perner includes in Mesocmlia seven or eight species fron1 the Lower Ludlow and Aymestry 

faunas in thelin1estones of the Bohemian etage E2 • To the genus are also referable llfurchisonia 

com1Jressa Liudstr<:hn, 3 fron1 the Ostergarnlower lin1estone, of similar age, in Gotland; Omlidium 

strebloceras Clarke, 4 fr01n the Devonian limestones at Dalhousie, New Brunswick; the present 

Chapn1an species described below; and perhaps also the British species Turritella or Iiolopella 

obsoleta Sowerby,5 from the Tilestones of Horeb Chapel and Felinclre, and the Eo-Devonian 

.1lf.urchisonia hebe Billings, 6 which is widespread in the Grande Greve limestone at Grande 

Greve, Indian Cove, etc., Gaspe Bay. 

MESOCCELIA TEN"£!ELLA sp. nov. 

Plate XIII, figures 6-11. 

1907. Crelidium tenue (pars). Clarke, New York State :Mus. Bull. 107, p. 190 (?),left-hand ~gure onl~; not descriptive 

text. 

Lower Dcvo~ic: Presque Isle Stream, Chapman Plantation, Maine. 

(?) Limestones: Ditlhousie, New Brunswick. 

Numerous incon1plete spires of a very high spired, 1nany-coiled Loxonema-like Murchisonia 

occur in the Chap1nan sandstone. The whorls are deeply rounded, with pron1inently excavated 

oblique sutures; the width of each whorl at right angles to the suture is three-fifths the "length" 

exposed between sutures. 'The umbilicus is minute or absent, and no reflection of the aperture 

is apparent. An obscure angula~io~1, evidently indicating the position of the slit band, is evident 

I Willlnrns, H. S., a.nd Gregory, H. E., Contributions to the geology of Maine: U. S. Geol. Survey Bull. 1G5, p. 86, 1900. 

3 Pornor, Jaroshw, SysUlme silurien du centre do Ia Bohl3rne, pt. 1, vol. 4, Gasteropodes, tome 2, p. 113, 1907. 

a Lindstrom, Gustaf, On the Silurian Gastropoda and Pteropoda of Gotland: Roy. Swedish Acad. Sci. Trans., vol.·19, No. G, p. 129, pl. 12, figs. 

15-19, 1884. 

• Clarke, J. M:., Now York State Mus. Bull. 107, p. 189, fig., 1907. 

n Soworby, J. C., in Murchison, R. I., 'I:ho Silurian s)'stem, p. G03, pl. 3, figs. 7a, 12f, 1839. 

o Clarke, J. M., Enrly Dovonic history· of New York nnd eastern North America: New York State Mus. Mem. 9, p. 153, pl. 17, figs. 31-32, 1908; 

os Crolidi·um Iiebe (Billings, 1874). 

5024G0-NO. 89-16--18 
274 FAUNA OF THE CHAPMAN SANDSTONE OF :MAINE. 

·in many molds, especially on the latest whorls. When present it is at the midheight of the 

whorl rather than nearer the suture. The shell is nacreous on the interior. The surface ornamentation must have been.very faint, for it is not preserved. 

Locality: Common in the Chapman sandstone 2 miles west of Presque Isle Stream, Chapman Township, Aroostook County, Maine. What is apparently the same form occurs at the 

end of the Tweedy road on Presque Isle Stream (locality 1099 L). This seems to be the shell 

referred to by Clarke as identical with his Omlidium tenue. A similar shell is rare on Edmunds 

Hill (locality 1099 C). 

U. S. National Museum, catalogue Nos. 59854-59856. 

Comparisons.-The text describing Clarke's Omlidium tenue, like his right-hand figure, refers~ 

to an angulated Murchisonia comparable with Oehlert's genus Goniostrophia. Clarke also compares Omlidium tenue with such angularly keeled murchisonids ( ~ Goniostrophia) as M. losseni 

Kayser, from the German Eo-Devonian, and M. a~gulata Phillips and varieties, from the 

Stringocephalus zone of the Meso-Devonian. Clarke's description of "sharply keeled whorls 

margined by a simple slit band to which the surface slopes in an almost direct plane without 

either convex or concave curvature" does not apply to any of our shells, nor does it apply to the 

form show:J;l in Clarke's left-hand figure, which resembles the shells here unqer discussion, but 

shows a slightly greater apical angle and a more conspicuous slit band. 

Mesocmlia tenuella sp. nov. seems most nearly allied to the imperfectly known British Tilestone Mesocmlia?. obsoleta (Sower by), from which it can with difficulty be distinguished. The 

Chapman shell, however, seems to have decidedly more than the nine whorls mentioned by 

Sower by for M. ( ~) ob.soleta and the whorls appear to be perhaps a trifle more inflated. 

~iESOC<ELIA ~ sp. cf. M. COMPACTA (Hall). 

The Chapman fauna includes representatives of a group of Murchisonire related to Mesocrelia 

Perner which· may, however, prove distinct from the extremely tall spired, typical forms of 

Mesocrelia. The shells referred to conform with Mesocrelia in the large number 9f whorls and, 

like Perner's genus, differ from Crelocaulus Oehlert in having the whorls more cylindrically 

rounded'·and the slit band less conspicuous a:!ld situated on the middle of the whorls rather than 

near the suture. The shells differ markedly fron1 typical Mesocrelia in having the whorls more 

compressed or compact, with less width between sutures, thus producing a shorter spire. The 

group includes the middle Silurian Mesocmlia com pres sa (Lindstrom), 1 from the lower limestones 

of Ostergarn; Murchisonia longispira Hall 2 and Murchisonia logani Hall,3 both from the Guelph 

dolomite at Galt, Ontario; the basal Helderbergian Loxonema? compacta Hall, 4 from the lower 

part of the Coeymans ("Pentamerus") lin1estone of the Helderberg group, Schoharie County, 

N. Y .. ; and the present species, from the late Helderbergian fauna of the Chapman sandstone. 

Lindstrom's species has the perforate axis and reflected lip of Crelocaulus Oehlert, but the whorls 

are deeply rounded· and the slit band is at the midheight, as in the Mesocrelia of Perner. 

The Chapman specimens are fragmentary spires which are characterized by narrow whorls; 

in external molds the width of the whorl between sutures is only two-fifths the length, and in 

internal molds the whorls appear narrower still. The whorls are deeply rounded. There does 

not appear to. have been any umbilicus or perforation in the narrow axis. The slit band when 

best preserved is only indistinct; it appears to be at the midheight in the upper whorls, where the 

faint strire of growth that mark the surface make a broad reentrant angle. 

. The fragments resemble Mesocmlia compacta (Hall) in the narrowness of the whorls and in 

the apparently somewhat fusifonn shape of the spire, but the·whorls in the Chapman shell are 

more cylindrical and have deeper sutures, in these respects ·approaching those of Lindstron1's 

.Gotlandian species Mesocmlia compressa. 

1 Lindstrom, Gustaf, The Silurian Gastropoda and Pteropoda of Gotland, p. 129, pl. 12, figs. 15-19, 1884. 

2 Hall, James, Paleontology of New York, vol. 2, p. 345, pl. 83, figs. 1, 2, 1852. 

a Idem, p. 346, pl. 83, figs. 4a, b. 

• Idem, vol. 3, p. 297, pl. 54, fig. 12, 1859. 
MOLLUSCA. 275 

Locality: Several fragmentary spires, too incmnplete for full specific description, occur in 

the softer beds of the Chap1nan sandstone along Presque Isle Stream, near the Tweedy road 

(locality 1099 A), Chapman Township, Aroostook County, Maine. 

U.S. National Museum, cataJogue No. 59857. . 

Genus CCELIDIUM Clarke and Ruedemann, 1903 (=C<ELOCAULUS Oehlert, 1888). 

The genus Crelocaulus was proposed by Oehlert 1 in· 1888 for highly turriculate murchisonoid 

shells which differ from Hormotoma Salter in possessing a narrow umbilicus that extends as a 

straight hollow canal up the vertical columella ~nd which have also a reflection of the lip. 

Other and perhaps more conspicuous characters which distinguish Cmlocaulus are the flattening 

of the whorls above the slit band, the shallow sutures, the position of the slit band near the 

suture in the upper whorls, and the usually greater number of whorls.. The generic name 

Crelidium was proposed by Clarke and R.uedemann 2 to supplant Oehlert's generic name Crelocaulus on the ground that the latter was preoccupied by Hall and Simpson,. 1887, for a subgenus of Bryozoa under Callopora. 

From Cmlocaulus there have been more recently dissociated the genera Ptychocaulus 

Pernm·, 1907; Catozone Perner,.1907; and Turritoma Ulrich and Scofield, 1897. Ptychocaulus, 

of which ]:lurchisonia bivittata ]{all, from the Guelph dolomite of Ontario and contemporaneous 

bods in Indiana is a characteristic An1erican species, has a secondary plication on the columellar 

lip; the genus Catazone has the whorls rounded as in I-Iormotoma and Mesocrelia; and Turri tom~ 

has the whorls flattened or even concave in the middle and also lacks the umbilicus or perforated 

columella of Crelocaulus, Ptyehocaulus, and Catazone. All four groups agree, however, in 

having the slit band only slightly removed above the suture. 

CmLIDIUM cf. C. PLANOGYRATUM (I-Iall). 

Plate XIII, figure la. 

?1850. Loxonema planogyrata. Hall, Paleontology of New York, vol. 3, p. 298, pl. 54, fig. 13. [Coeymans] "Pentamerus" lim~stone of the Helderberg: Schoharla County, N.Y. 

A third type of Murchisonia in the Chapman sandstone has the whorls flatter a~id the 

.sutures less deeply excava.ted than in the types already described; in the upper whorls .the slit 

band is below the midheight and only a little above the suture. In these features the shell 

conforms with the superficial -characteristics of Crelidium ( = Omlocaulus), hut the columellar and 

apertural characters have not been observed. 

The width of the whorl between sutures is three-fifths of the length. The broad and, in 

external molds, fairly conspicuous slit band produces a blunt vertical subangulation in the 

lower part of the whorl. The slit band is separated by hardly more than its width from the 

suture; above t.he band the surface· of the whorls is nearly plane-hardly at all inflated. 

Locality: Chapman sandstone, along Presque Isle Stream, near the end of the Tweedy 

road (locality 1099 L), Chapman Township, Aroostook County, Maine. 

U. S. National Museum, catalogue No. 59858. 

Oomparisons.-The shell resembles Omlocaulus davidsoni Oehlert 3 from the French (Mayenne) Eo-Devonian; Murchisonia [ Omlocaulus] cingulata (Risinger) 4 and M. [ 0.] obtusarigulata 

Lindstrom} from the highes.t Silurian limestones of Gotland; and 111. [0.] egregia Billings,6 from 

the Oriskan_y fauna of Gaspe; but in the Chapman s~ell the whorls are a trifle wider ("taller") 

in proportion to their length. Still closer resemblance to the Helderbergian Loxonema planogyrata I-Iall, from which, indeed, the Chapman shell seems indistinguishable; but it must be 

emphasized that both the Chapman and Helderberg fossils are very poorly preserved. 

1 Oohlort, D.P., Descriptions de quelq~JOS especes devoniennes du departement de Ia Mayenne: Soc. etudes sci. Angers B~11I. for 1887, p. 20, 1888. 

~Clarke, J. M., and Ruedomann, Rudolf, Guelph fauna in the State of New York: New York State Mus. Mem. 5, p. 65, 1903. 

a Oohlort, D. P., op. cit., p. 21, pl. 7, Jlg. 4. 

• See Lindstrom, Gustar, op cit., p. 1:l7, pl. 12, figs. 9, 10. 

G Idem, p. 128, pl. 12, fig. 12 (not fig. '7, which is a Goniostropha). 

o Clarke, J. M:., New York State Mus. Mom. 9, p. 152, pl. 17, figs. 29-30, 1908. 
276 FAUNA OF THE CHAPMAN SANDSTONE OF MAINE. 

Genus GONIOSTROPHA Oehlert, 1888_. 

The genus Goniostropha Oehlert was defined to include son1e French Eo-Devon1an elon-

. gated Murchisonim having the slit band situated on a prominent and persistent angulation of 

the whorls which occupies the midheight between the sutures. The position of the slit band 

.is similar to that in Hormotoma S~lter, fron1 which Oehlert's genus is easily distinguishable by 

the angulation and by the typically flat, sloping profile of the whorls from the keeled band to 

the sutures. From Cmlidium (Cmlocaulus) Goniostropha js distinguished by its more pronounced angulation and by the position of the angulati.o~ and slit band near ·the midheight of 

the whorls rather than near the suture. Goniostropha was also defined by Oehlert as being 

nonumbilicate, and this character would add another distinction from Cmlidiun1 (Cmlocaulus), 

in which the vertical columeUa has a wide eanal ascending upward through it. Perner, however, places little reliance on the supposed absence of an· umbilic~s in Goniostropha; and Clarke 

and Ruedemann's figures of _Murchisonia [GoniostrojJha] macrospira Hall indicate that the columella in the same individual may in some whorls be perforate, in others imperforate.1 

klurchisonia macrospira Hall, from the Guelph, is a typical Goniostropha, as are also M. 

extenuata I-Iall and ]f. minuta I-Iall, from the Manlius limestone; Gmlidium tenue (pars) Clarke,2 

from the late Silurian or Devonian limestones at Dalhousie, N mv Brunswick; 1..1urchisonia 

hercynica Roemer, from the Getman Eo-Devonian; Murchisonia angulata D' Archiac and 

De V erneuil, from the European Meso-Devonian; and l.furchisonia micula Hall, from the 

American Meso-Devonian. Several other species are known from the Silurian and Devonian 

of Europe, and in both Europe and America the genus appears to continue into the Carboniferous: 

GONIOSTR.OPHA. CHAPMAN! sp. nov. 

Plate XII, figure 28. 

A small shell with tapering conoid spire in the ·chapman fauna belongs to the genus Goniostropha and seems to require specific appellation. The fragn1entary spire is 8 n1illimeters long, 

2 millimeters wide at the upper end, and 6 millimeters wide at the base, and in this portion 

shows four whorls; the apex is broken away. The whorls are half as wide (''tall") as long, 

with oblique sutures, and show a pronounced sharp angulation at the midheight. The surface 

slope from the median earination to the sutures is but slightly convex, nearly plane. 

The species seems readily distinguishable from the described species of Goniostropha by 

its small size, tapering conic spire, sharp simple median carination; and whorls twice as long 

as wide, with oblique sutures. 

Locality: Chapman sandstone, 2 miles west of Presque Isle Stream (locality 1099 J), Chapman Township, Aroostook County, Maine. 

U.S. National Museum, catalogue No. 59859. 

Family TROCHID.tE Adams. 

Genus PSEUDOTECTUS Perner, 1907 (PALlEONUSTUS Perner, 1903). 

The genus Paleonustus was founded by Perner 3 for fossils resembling the well-known 

Silurian Euomphalopter'l.ts alatus in having a peripheral keel bu~ no slit band, and easily distinguished from the Pleurotomarias, with which the ~hells might otherwise be confused, in lacking 

the retral swing of the strire of growth near the region of the keel or supposed slit band. From 

Euomphalopterus Roemer Paleonust"\.ls differs chiefly in having a higher and more nearly 

straight-sided conic spire and a less open umbilicus or no umbilicus at all; moreover, the keel 

is immediately above or at the suture in Paleonustus, instead of higher, as in Euomphalopterus. 

In Euomphalopterus also the aperture is circular and holostomate; in Paleonustus the aperture 

is more or less pentagonal, there is a narrow columella, and the inner lip is interrupted by the 

body whorl. Euomphalopterus is usually more highly ornate than Paleonustus. 

1 See Clarke, J. M., and Ruedemaun, Rudolf, The Guelph fauna in the State of New York: New York State Mus. Mem .. 5 .. p. 65, pl. 7, figs. 6, 

7, 8, etc., 1903. . , 2 Clarke, J. M., Some new Devonic fossils: New York State Mus. Bull. 107, p.l90, text and right-hand figure, 190i. 

a Peruer, Jarosl.av, Syst~me silurien du centre de la Boh~me, pt. 1, vol. 4, Gasteropodes, tome 1, pl. 57, figs. 36-40, 1903. 
MOLLUSCA. 277 

A Silurian group intermediate between Euomphalopterus Roemer and Paleonustus Perner 

includes tho Pleurotomaria ~ 1Jrete~r;ta, P. togata, and Trochus astraliformis of Lindstrom/ and son1e 

other species frmn Gotland, as well as Euomphalopter1..ts alata var. Zimatoiclea Kindle and Breger, 2 

frmn beds in Indiana contemporaneous with the Guelph of Ontario. In this group th~ flange 

is located at the suture, and the spire is sometimes conic, as in Paleonustus, but the n1outh is 

circular, with holostomate lip; the deep umbilicus is continued upward through the oenter of 

the spire, and finally the shells nre more strongly ornate, as in Euomphalopterus. , 

In 1907 Perner 3 abandoned the nan1e Paleonustus on the ground that it had been based 

on 11 fu.lse conception of supposed relationship with the Recent genus Onustus; Pseudotectus 

was substituted instead, the new name being suggested by the resmnblance to the TriassicRecent genus Tectus. As Paleonustus had not been genericaliy described nor adopted prior 

to 1907, P~rner's abandmunent of his own generic name Pa.Ieonustus may be excused and 

Pseudotectus accepted. 

Along with Pseudotectus Perner described, in 1907, the new genus Streptotrochus,4 which 

included son1e Silurian gastropods that agree with Pseudotectus in general external appearance, especially in the conic spire and in the peripheral keel, situated at or just above the 

suture. · In Streptotrochus, however, the keel, though conspicuously developed, is never 

extended into the pronounced sheetlike or flangelike expansion which characterizes Pseudotectus Perner and Euomphalopterus Romner. However, when this flange is broken away, 

as it is in n1any specimens, Pseudotectus and Streptotrochus are distinguishable only by the 

deeper 1.nnbilicus of Streptotrochus. 

In the Chapman sandstone ·occurs a shell, well figured by Clarke, who called it Eotomarict 

hitchcocki, having a pronounced keel, which, by its simulation· of a slit band, causes the shell 

to be easily confused with Pleurotomaria or its various allies. That the shell is not a Pleurotmnaria and that the outer lip has !10ither the slit nor the >-shaped sinus of that genus is 

readily evinced, even in fragrrwntary shells, by the line~ of growth. These, though they curve 

backward down to the keel, do not curve forward below the keel. Hence the latter has only 

the suggestion, not the function, of a slit band. The Chapman shells confonn with the Pseudotectus and Streptotrochus of Perner. The extended flange of Pseudotectus has not yet 

been observed by us, and the lack of it would semn to ally .the shell with Streptotrochus. The 

lack of the flange may be more apparent than real, however, and is possibly due to fracture 

or imperfect material. Clarke, indeed, describes the whorl as ''sharply carinate or even 

extended into a keel or flange." On the basis of his statement the shell is here referred to 

Pseudotectus, a reference which seems the 1nore proper, because the shell lacks the deep 

1.nnbilicus of Streptotrochus:, the colun1ella being closed and having only a small umbilicus 

developed, as in Pseudotect1ts comes Barrande. Perner 5 describes Pseudotectus as without 

umbilicus, but a 1ninute deep umbilicus is distinctly indicated in his text figures. This minute 

umbilicus and the apertural characters are identical with similar features in Pseuclotectus hitchcoclci (Clarke). 

In the 1\..lnerican faunas the genus Pseudotectus seen1s to be represented by the Pleurotomctria eloroidea Kindle and Breger,6 fro1n the dolmnitic limestones with Guelph fauna at • 

I-Iuntington, in northern Indiana. In Europe Pseud9tectus includes Trochus Zunclgreni Lindstrom/ fro1n the late Silurian (Upper Ludlow) li1nestones at Samsugn, in Othmn, and at Lutterhorn, in Faro, Gotland; Pseudotectus comes Perner.,S frmn the Bohemian Eo-Devonian of 

Konieprus; and the shell c2Jled Euomphalopterus conoidea Oehlert,9 from the French Eo-Devonian. The range of the genus is therefore from the middle part of the Silurian to the Lower 

Devonian, inclusive. 

1 Lindstrom, Gustaf, On tho Silurian Gastropoda and Pteropoda of Gotland, pis. 11, 14, 1884. 2 !Gndlo, K llf., and Breger, C. L., J>aieontology of the Niagara of northern Indiana: Indiana Dept. Geology and Nat. Res. Twenty-eighth 

Ann. llopt., pl. 14, figs. 3, 4, 1904. 

a Porncr, Jaroslav, op. cit., tome 2, p. 241, footnote, 1907. 

• Idem, p. 238. · 

o Idom, p. 240. 

a Klndlo, E. M., and Breger, C. L., op. cit., p. 457, pl. 13, figs. 1, 2. 7 Lindstrom, Gustaf, On the Silurian Gastropoda and Pteropoda of Gotland, p. 149, pl. H, figs. 47-53, 1884. 

e Perncr, Jaroslav, op. cit., p. 241. 9 Oehlert, D. P ., Sur le d~vonien des environs d' Angers: Soc. geol. France Bull., 3d ser., vol. 17, p. 772, pl. 19, fig. 5, 1890. 
278 FAUNA OF THE CHAPMAN SANDSTONE OF MAINE. 

PsEUDOTECTus HITCHCOCK! (Clarke). 

Plate XII, figure 17. 

cf. 1884. Trochuslundgreni. Lindstrom, K. Svenska Vetensk. Akad. Handl., vol. 19, No.6, p. 149, pl.14, figs. 46-53. 

N eo-Silurian limestones: Samsugn in Othem; Lutterhorn, Faro. · 

1907. Eotomaria hitchcocki." Clarke, New York State Mus. Bull. 107, p. 190, figs. 

Low':r Devonic: Presque Isle Stream and in the burnt lands 2 miles west, Chapman Plant~tion, Maine. 

The typical form of this shell from Presque Isle Stream is represented in our collection by 

one or .two crushed specimens which are too poorly preserved to show well the distinctive 

specific characters. The following description is therefore drawn up mostly from Clarke's work: 

Spire rather high, conical; proportion of height to width as 11:10. Angle of spire 70°. 

Whorls contiguous throughout; six 1 in number; angular, sharply keeled a little below the 

midheight, overlapping the lower third to a point just below the keel. From.the narrow keel 

which forms the periphery of the whorl the profile toward the suture is nearly straight, gently 

. concave in the lower half, gently convex just below the suture, thus giving the shell a conical 

profile from the tip of the spire to the keel of the body whorl. Sutures not conspicuous, hardly 

discernible; located immediately below the peripheral keel, very nearly horizontal. The total 

height of the body whorl is a little less than half the total height of the spire. The greatest 

width is along the keel, which is peripheral. The body· whorl is slightly concave immediately 

below the keel, becoming convex over the greater portion to the umbilicus. The base of the 

shell is broad and flat for nearly the full width. A narrow umbilicus is distinctly developed, 

although it seems to be closed by the union, in the center of the spire, of the inner sides of the 

whorls. Mouth subpentagonal, as wide as high or wider, angulated by the peripheral keel, which 

does not bear a slit band. The base of the mouth is broadly rounded. The lower part of the 

inner lip is vertical and slightly thickened, with a narrow untwisted columella. Peristome 

interrupted by the body whorl. The upper part of the inner portion of the mouth is formed 

by the next upper whorl. · 

·The surface is nearly sinooth, but is covered with tenuistriate lines of growth directed 

backward from the suture to the keel. They do not arch or sweep farther back on approaching the keel, but continue in their direction across the keel and below it. 

Height of shell 21 to 22 millimeters; width, 19 to 20 millimeters. 

Locality: Chapman sandstone, Presque Isle Stream (locality 1099 A), Chapman. Township, 

Aroostook County, Maine. 

U.S. National Museum, catalogue No. 59860. 

Oomparisons.-Pseudotectus hitchcocki, from the Chapman sandstone, seems scarcely to be· 

distinguished from the Gotland species Trochus [Pseudotectus] lundgreni Lindstrom, in which the 

keel is somewhat nearer the base of the body whorl and mouth; and the profile from keel to 

suture is less sigmoidal. These, however, are minor distinct~ons. · 

PsEUDOTECTUS ~ DECIDUUS sp. nov. 

Plate XII, figures 18-27. 

In the region west of Presque· Isle Stream there is an abundant species closely related t~ 

P. hitchcocki, but preserved as partial casts or internal molds, making it very difficult to learn 

the real external structure. The form may be distinguished from the typical Pl:'esque Isle 

Stream shell by a tendency of the last whorl to become free or irregular. The internal molds 

show the peripheral keel, which is fairly well developed on the body whorl, becoming very 

pronounced and angular just back of the mouth. ·On the upper whorls, however, the angula-

. tion of the keel is usually not discernible on internal molds, the whorls here appearing rounded 

except that occasionally the whorl next the body whorl may be slightly angulated. The 

mouth was slightly expanded, to judge from the internal mold. There appears to have been, 

also, some variation in the height of the spire above the normal. Externally there was a narrow 

flat shoulder below the suture and a vertic~l rim above, neither of which is definable on internal 

molds. 

1 Clarke mentions only four or five whorls, but his figures show six or seven whorls, and that number is also indicated by our less perfect 

specimens. 
MOLLUSCA. 279 

Locality: Chapman sandstone, 2 miles west of Presque Isle St.ream (locality 1099 J), 

Chapn1an Township, Aroostook County, Maine. 

U.S. National Museum, catalogue No. 59861. 

Oo:mparisons.-This species appears to be similar to Trochus incisus Lindstrom/ from the 

highest Silurian of Gotland, in the tendency toward the deciduous character of the body whorl. 

Streptotrochus incisum Lindstrom has a taller spire.. Species may perhaps be referable to 

Streptotrochus rather than to Pseudot~ctus. 

PsEUDOTECTUS ~ sp. indet. 

Plate XII, figure 16. 

Some poorly preserved internal molds of a species of Pseudotectus 0) have been found 

loose in the Chapman sandstone on Edmunds Hill. These specimens, like many of the internal 

molds from the locality west of Presque Isle Stream, show angulation only on the body whorl, 

the upper whorls appearing rounded. The fossil is a small species, of Holopea-like outline, with 

only three or four whorls, but is too poorly preserved to be recognizable specifically; and is 

listed simply as representing the genus·. 

Locality: .Ch,apn1an sandstone, Edmunds Hill (locality 1099 C), Chapman Township, 

Aroostook County, Maine. 

U. S. National Museum, eatalogue No. 59.862. 

Family PSEUDOMELANIIDiE Fischer. 

Genus LOXONEMA Phillips. 

LOXONEMA WELLERIANA sp. nOV. 

Plate XIII, figures 2, 3, 5. 

cf.l903. Loxonema jerseyense (pars). Weller, New Jersey Geol. Survey, P~leontology, vol. 3, pp. 95,335, pl. 43, fig.lO 

(not fig. 9). 

Trilobite beds (basal Oris~auy): Trilobite Ridge, New York and New Jersey. 

Shell of moderate size;. a high, turriculate, closely coiled spiro, showing in the best preserved specimen over 12 wi10rls, probably about 13 or 14. The apical whorls are ·minute and 

usually u.bsent; the last six whorls occupy seven-ninths the total height of the spire. Apical 

angle 19° to 20°. The whorls are convexly rounded, rather strongly, with sutures sharp and 

moderately oblique (10°). The width of the whorl exposed between the sutures is about half 

the length, the proportion of length to width varying from 2: 1 to 1.9: 1. Each of the last four 

whorls is 1. 7 to 1.8 times a.s long as the next upper whorl. Aperture unknown. 

The. ornamentation consists of sigmoidnJ. lines of growth; these vary in strength, continuity, and direction. They are slightly convex at the base, but swing back into a reentrant, 

shallowly concave arch, which includes most of the width of the whorl. Below the suture the 

strire again swing forward, and as a .rule continue concave up to the suture, though in many 

specimens they become convex and nearly direct for less than a millimeter just below the suture. 

In strength the lines are variable. ·For short patches they may become even, about eight in 

the space of 2 millimeters on the middle of the whorl, or they may become very fine and aggregated into fascicules or wrinkles, about three or four of the latter in the space of 2 millimeters. 

The strire arch back shallowly, with the greatest depth of arch variable, at or above the midheight' of the whorls. The ornamentation is strongest in the arch of the strire near the middle 

portion of the whorls. In some external molds the strire may appear strongest near the suture, 

but this appearance is due to erosion of the shell surface on the exposed parts of the whorls. 

A specimen with the extreme ap~x incomplete but still pres~rving 12 whorls has a height 

of 27.75 millimeters, a width at the base of 8 millimeters, and the basal six whorls are 21.5 

1niliimeters high ariel the basal four whorls 16.75 millimeters high .. Another tragment preserving 

four whorls has a height of 17 millimeters and width _of 8.25 D.?-iJli:meters. A third and larger 

fragment with six whorls was 24 millimeters long and 10.5 millimeters wide at the base. 

1 Lindstrom, Gustaf, op. cit., p. 151, pl. 14, figs. 22-31. 

' 
280 FAUNA OF THE CHAPMAN SANDSTONE OF MAINE. 

The species 1nay be recognized by the deep convexity of its whorls, the sharp oblique 

sutures, the width of the whorls (half the length), the narrow spire, gradual increase of the 

whorls, shallow arch of the strirn of growth, and strong bu~ varying ornan1entation. 

Locality: Moose River sandstone, Detroit (locality 1100 A), Son1erset County, Maine. 

Common, along with Leptocmlia flabellites Conrad, Spirffer antarcticus Morris and Sharpe, Spirifer 

arenosus Conrad, S. murchisoni Castelnau, Leptostrophia perplana Conrad (L. blainvillei Billings), 

etc. These shell.s are often overspread by an explanate bryozoan. 

U. S. National Museum, catalogue No. 59863. 

Oomparisons.-L. welleriana appro'aches most nearly, among described forn1s of Loxonema, 

L. subtilist'riata Oehlert/ from the French (Mayenne) Eo-Devonian; bu~ the ornamentation of 

th~ Ame~ican shell is less uniformly fine a:r;td becomes in places much coarser than in ~he French 

species. The latter also has the greatest depth of the arch of the strirn uniformly above the 

nliddle, whereas in the Chapman form it is variable and mos~ commonly nearer ~he middle. 

LoxoNEMA .JERSEYENSE Weller. 

Plate XIII, figures 1, 4. 

1903. Loxonemajerseyense. Weller, New Jersey Geol. Survey, Paleontology, vol. 3, pp. 95, 335·, pl. 43, figs. 8, 9 (not 

fig. 10). I 

Trilobite beds (basal Oriskany): Trilobite Ridge, New York-and New Jersey. 

In the basal Oriskany, at Trilobite Ridge, N.Y., in New Jersey, and in the Lower Coblenzian fauna of t.he Moose River sandstone at Detroit, Maine, occur two associated· but distinct forms of Loxonema. One of these is described above as L. welleriana sp." nov.; the other 

is here called by the ]).arne L. jerseyense Weller, which is restricted to this form. Both forms were 

included by Weller in the species L. jerseyense. 

L. jerseyense s. str. conforms with L. welleriana in the character and variability of its ornamentation but is easily distinguished by having the whorls much wider in proportion to the 

length. Indeed, the whorls are nearly as wide as long in L. jerseyense, the proportion <?f lengt.h 

to width ranging from 11:8 to nearly 12:8, compared with 19: 10 to 2: 1 in L. welleriana. The 

spire is therefore more tapering in L. j"erseyense,· the height of the. fC?ur basal whorls of the spire 

is 2-fto ?t times the width, compared with a ratio slightly greater than 2:1 in L. welleriana. 

Locality: Moose River sandstone, Detroit, Somerset County, Maine, along with L. welleriana sp. nov. L. welleriana is n1ore common than L. jerseyense in the Maine collections, but 

in New Jersey the reverse is true. 

U.S. National Museum, catalogue No. 59864. 

Genus AURIPTYGMA Perner, 1907. 

The genus Auriptygma was erected by Perner 2 in 1903, and the genotype, A. fortior (Barrande) from the Aymestrian fauna of ~tage E2

, was figured, bu,t ·the genus was not described 

until 1907.3 A translation from the French of Perner's diagnosis of Auriptygma is as follows: . . 

Shell terbinate; whorls inflated, scalariform; apex pointed; sutures straight and deep; last whorl very much 

developed. Mouth elliptical, elongated toward the base. Inner lip neither thickened nor tucked -in, but simply 

undulating and merging by simple passage into the columella; the latter is solid and straight. Surface strire transverse, distinCt, faintly inclined, a little arched. . " 

Auriptygma offers the closest resemblance to the early Paleozoic gastropods which have 

been placed in the genera Holopea Hall and Macrochilina Bayle ( ~ Macrocheilus Phillips, 

Phillips's name -being preoccupied). In Macrochilina, founded on the British Devonian M. 

acuta, there is no umbilicus whatever, and the base of the inner lip is tucked into a short tortuous 

columella. In M. arculata (Goldfuss) and several other species of Macrochilina there is a pronounced twist at the base of the columella, producing a columellar fold; Kittl,·' ind~ed, regards 

t Oehlert, D. P., Descriptions de quelques especes devoniennes du departement de Ia Mayenne: Soc. etudes sci. Angers Bull., 1887, p.12, pl. 7, 

fig.l. 

2 Perner, Jaroslav, SysWme silurien du centre de la Boheme, pt. 1, vol. 4, Gasteropodes, tome 1, pl. 61, figs. 51-54, 1903. 

a Idem, tome 2, p. 361, text figures 260, 261, 1907.. · 

4 Kittl, Ernst, Die Gastropoden der Schichten von St. Cassian der siidalpinen 'l'rias, pt. 3: K. k. Naturhlst. Hofmuseum Annalen, vol. 9, 

p. 208,_1894. 
MOLLUSCA. 281 

this coluniellar fold as characteristic of the Paleozoic for1ns of Macrochilina and describes several 

Inter spo(jies cf :Macrochilina havilng one or two additional broadly rounded folds higher up on 

tho columella or inner lip. Aur:iptygma has a 1nuch simpler inner lip than that of even the 

sin1plos t fonns of lV[acrochilina. · · 

There is so1ne difficulty in distinguishing Auriptygma Perner fr01n Holopea of I-Iall and 

authors, for I-Iall's genus is but little understood. Holopea Hall is founded on the Trenton 

limestone species Flolopea symmetrica fiall; 1 the generic .details of the species are unknown, 

the genus having been based 1nore or less on external form. Holopea was supposed to have 

boon recognized subsequently in the Now York Devonian and elsewhere, but it is not certain, 

perhaps not even probable, that the Devonian shells called Holopea 2 correspond generically 

with the Trenton lin1es.tone types of fiolopea. The apertural and other generic characters of 

I-Iolopea can best be elucidated by comparison with the An1erican Ordovician species described 

and figured by lnrich and Scofield 3 and with the European late Ordovician shells of similar 

typo described by Kokon. '

1 fiow·eve~, there n1ust first be removed frmn the higher or buccinoidspired shells characteristic of f[olopea the large number of so-called I-Iolopea ·species which 

have a lower naticoid spiro and, usually, a deep umbilicus, a continuous circular peristome, and 

one or two whorls less than the typical I-Iolopea. Typical Holopea, even 1nore so than Macrochilina, presents superficially a striking similarity to Auriptygma; the u1nbilicus is n1inute or 

absent, the cohunella and thickening of the inner lip are absent, the inner lip is interrupted by 

tho body whorl and· to.ward tho base is elongated and'slightly explanate. That the stronger 

and posteriorly arching st~·ire of Auriptygma are alone sufficient to distinguish the genus fron1 

IIolopea I-Iall is questionable. With Perner, I believe that the name Auriptygma, which 

defines a concisely demarkable gastropod structure, is preferable to the loosely applied name 

IIolopea, which semns to have served authors as a blanket name for uriplaced shells of this 

genernl type. In tho tenuity of the surface strire and in the slightly less rounded or more nearly 

vertical-shouldered whorls, as well as in the distinct though l'ninute uinbilicus, the Chapman 

shells under discussion conforn1 n1ore nearly with Holopea Hall than with the type species of 

Auriptygn1a. · 

HoLOI'EA (AuRIPTYGMA) BEUSHAUSENI Clarke. 

Plate XII, figures 1-15. 

1907. Ifolopea beushauseni. Clarke, New York State Mus. Bull. 107, p. 188, figs. 

Lower Devonic: Presque Isle Stream, Edmunds Hill(?), Chapman Plantation, Aroostook County, Maine. 

Shells rather large in the typicnl forms. Spire moderately high, buccinoid; proportion of 

height to width as 3:2. Anglo of spire betweon 58° and 70°. Whorls five or six; contiguous; 

convex, rather flattened or vertical below the shoulders; overlapping the lower fqurth; broadest 

below tho middle. Sutures rather strongly impressed, profoundly so in internal molds; obliquity 

frorn t.ho horizontal 5° to 25(), depending largely· upon distortion and pressure in the rock;· 

usunlly about 20°. The height of the body whorl exclusive of the 1nouth is a trifle less than tho 

height of tho rest of the spire. Tho total height of the body whorl is equal to two-thirds the 

height of .tho shell. The greatest width is below the middle. The nrouth is elongate, oval in 

outline; tho base is broadly :rounded, not tapering, and in good specimens is explanate or 

slightly recurved. Un1bilicus. absent or minute. Internal molds show a straight, narrow 

canal extending up the 1nidcllo of the spire, apparently a little wider than·the thickness of the 

shell. Whether this cann,l was hollow or filled is not known. 

Internal n1olds and sculpture casts are quite smooth. One external 1nold was also quite. 

sn1ooth, and another showed only extremely tenuous lines of growth. The surface may tl?-erefore be considered to have been sn1ooth, or very nearly so. 

1 Hall, James, Paleontology of New York, vol. 1, p."170, pl. 3i, fig. 1, 1847. 

2 ldcm, vol. 5, pt. 2, pl. 12, 1879. 

s Ulrich, E. 0., and Scofield, W. H., 'ehe Lower Silurian Gastropoda of Minnesota: Geology of Minnesota, vol. 3, pt. 2, Paleontology, p. 1065, 

pl. 70, 18ll7. 

Kokon, Ernst, .Die Gastropoden des balt.ischen Untersilurs: Acad. imp. sci. St. Petersbourg Bull., 5th ser.,',vol. i, No.2, p. 193, 1897. 
282 FAUNA OF THE CHAPMAN SANDSTONE OF MAINE. 

Locality: Chapm,an sandstone, on Presque Isle Stream, at the end of the Tweedy road 

(localities 1099 A and 1099 L), Chapman Township, Aroostook County, Maine. Apparently 

the same species occurs also on Edmunds Hill (localities 1099 C and 1099 M); and a smaller 

species of the same genus occurs abundantly in the calcareous Chapn1an sandstone west of 

Presque Isle Stream (localities 1099 J, 1099 K, and ·1099 L). The specimens are rather poorly 

preserved, and it is by no means certain that they are all cospecific. Indeed, in the case of the 

lamellibranchs which are better preserved than these gastropods, the representatives of a genus 

from th~ Edmunds Hill locality, however closely allied, are in general specifically distinct from 

those·of the Presque Isle Stream localities. Possibly better material would show the gastropods also to be specifically distinct. 

U. S. National Museum, catalogue Nos. 59865 to 59869. 

Oomparisons.-From Auriptygma fortior (Barrande) Perner this species differs chiefly in 

having the profile of the whorls more nearly vertical. The outer extremity of the mouth is 

below the midheight in the Chapman species, instead of above; the mouth is a little more 

explanate than is apparent in the Bohemian figures; and the ornamentation is much more 

subdued. 

The explanate mouth and general buccinoid outline suggest a similarity with Macrocheilus 

sp. Beushausen, 1 from the Siegen fauna of the Bockberg, in the Harz, but the German fossil 

has a decidedly higher spire and stronger ornamentation. 

Class CEPHALOPODA. 

Family ORTHOCERATID.tE. 

Genus ORTHOCERAS Breyn. 

0RTHOCERAS sp. ( 10. NORUMBEG1E Clarke). 

?1907. Orthoceras nommbegm. Clarke, New York State Mus. Bull. 107, pp. 177-178, figs. 

Lower Devonic: Edmunds Hill, Chapman Plantation, Maine. 

A few fragments of Orthoceras have been obtained from the Chapman sandstone of 

Edmunds Hill, sufficient to establish the presence of these marine organisms in the Chapman 

fauna; but specific characters can .not be defined from such imperfect material. The several 

fragments are of similar size and might belong to a single species. They represent a slender, 

1nedium-sized shell, varying in diameter from 13 to 20 1nillimeters. The chamber of habitation 

is represented by a fragment 20 millimeters wide and preserving a length of 35 1nillimeters. 

The chambers are one-third as long as they are wide. The sept~ are arched and the siphuncle 

central and small. . 

The fragments may possibly represent smaller individuals of the large and bizarrely ornamented Orthoceras norumbegce Clarke, the chamber of habitation of which was described from 

the same locality. 

Locality: Chapman sandstone, Edmunds Hill ·(localities 1099 C and 1099 M), Chapman 

Township, Aroostook County, Maine. 

U.S. National Museum, catalogue Nos. 59870, 59871. 

0RTHOCERAS PRINCIANA sp. nov. 

Plate XIII, figure 17. 

Two species of snlooth, typical Orthoceras from the calcareous Moose River sandston~ are 

represented in our collections by incomplete specimens. The larger form, to which is applied. 

the name 0~ princiana, is distinguished by the n1oderately deep chambers, the deep tra:'nsvers~. 

septa, the subcentral siphuncle, a1~d the rapid tapering of the shell. A fragment shm,ys -the· 

cone expanding from 32 to 36 millimeters in a length of 30 millimeters. Three chambers are'· 

included in this distance, the average depth of the chambers between sutures being, therefore, 

1 Beushausen, Louis, Beitrage zur Kenntniss des Oberharzer Spiriferensandsteins und seiner Fauna: Abh. geol. Specialkarte Preussen, 

vol. 6, pt. 1, p. 52, pl. 1. fig. 7, 1884. 
MOLLUSCA. 283 

tlu·ee-tenths the width. The septa are deeply convex, extending below the suture approxinuttely two-fifths the height of the chan1ber above the suture. The siphuncle appears to have 

been very nearly though probab]y not quite central; it is 3 millimeters or more in diameter. 

The surface is devoid of ornan1en1Gation. 

Locality: Moose River sandstone, Son1erset County, Maine. The shells were collected by 

Mr. I-Iarold W. Prince, after whmn the species is named. 

U. S. National Museun1, cata1ogue No. 59872. . 

0R.THOCERAS PARLINENSE sp. nov. 

Plate XIII, figures ?21, 25. 

A second species of smooth Orthoceras in the Moose River sandstone fauna 1s a smaller 

shell, with slender, more tapering cone, very deep septa, and a central proportionately large 

siphuncle. In shells only 3 millimeters wide the chambers are 2 millimeters deep; they maintain a nearly uniform depth regardless of the size of the shell, and are 2.8 millimeters deep in 

shells 6 millimeters thick. About 2.5 millimeters represents the average n.nd usual distance 

between sutures. The septa are transverse and very· deeply arched; they extend below the 

sutures for a distance equal to the depth of the chambers between sutures. The siphuncle is 

central and is proportionately very broad, 1.5 to 2 millimeters in thickness-equal to one-third 

to one-fourth the dian1eter of the shell. The specimen figure 25 is the type of the species and 

figuTe 21 is referred provisionally to this species. 

Locality: Moose River sandstone, Parlin Pond, Somerset County, ~fn.ine~ 

U.S. National Museum, catalogue No. 59873. 

Suborder PTEROPODA• 

Family TENTACULITIDIE Walcott. 

Genus TENTACULITES Schlotheim, 1820. 

TJ!lNTACULITES SCHLOTHEIMI Koken. 

Plate V, figure 30; Plate XIV, figures 23, 24 .. · 

1820. Tentaculites annulatus var. Schllotheim, Petrefaktenkunde, p.·377 (pars). 

Lower Devonian: The Schalke, Prussia. 

189!>. Tentaculites schlotheirni. Koken,, Deutsch. geol. Gesell. Zeitschr, vol. 41, p. 82. 

Lower Devonian: The Schalke, Prussia. . 

1896. Tentaculites schlotheinti. Koleen., Die Leitfossilien, p. 540. 

Lower and Upper Coblenzian: Rhenish Prussia. 

1900. Tentaculites .~chlotheirni. Giirich, Ueber Tentaculiten und Nowakien: Schlesischen Gesell. vaterlandische 

Kultur Jahresb., Natnrw.-Abtheil., vol. 77, p. 34. 

Lower Devonian: Prussi~. 

1907. Tentaculites scalatis (not of authors). Clarke, New York State Mus. Bull. 107, p. 1i4. 

Lower Devonic: Edmunds Hill, Chapman. Plantation, }.1aine. 

Shell a free tapering con€: of 8° apical angle, in 1nature specimens :12.25 millimeters long, 

passing fron1 a width of 0.65 to 2.5 millimeters, and increasing i millimeter in width in a distance 

of 6.62 n1illhneters. Annulations equal, eight or nine in number in a space of 5 millimeters 

where the sheH is 2 n1illin1eters thick, eight to nine in number in a apace of 2 millimeters where. 

the cone is only 0.66 to 0.75 milihneter thi~k. The annulations are cro.wde"d, with interspaces 

usuAlly only slightly broader than the ribs.. Very rarely an interspace nearly twice .as wide as. 

the ribs 1nay occur; but frequently the interspaces are scarcely as wide as the ribs. . As seen. 

in good specilnens, the ribs are strongly elevated and the interspaces deeply ·e~oav-ated. . The 

surface is covered with very fine, threadlike, equal transverse or horizontal strim covering both. 

the ribs and the interspaces. Fron1 six to eight. of these may .be co.unted .in. the. space of a 

tnillilneter where the shell is a. little over 2 n1illimeters wide. In the sandstonea the finer· ornanlentation is rarely preserved; in n1ost external moids both the ribs and interspaces appear to 

be devoid of fine strim, ·and only in the cleanest specimens do these show. The transverse 
284 Fl\.UNA OF THE CHAPMAN SANDSTONE OF MAINE. 

striffi are usually parallel to the rib,s and interspaces, but where the ribs are slightly oblique 

the finer striffi are transverse and cut obliquely across the ribs in a very .small angle. There 

are not more than four striffi on either a rib or on an interspace, and commonly only three. 

Fr'agrnents about 2 centimeters long and 2 to 2.3 1nillimetera wide occur abundantly. 

Locality: Chapman sandstone (Pl. XIV, figs. 23, 24); common with Chonet~s striatissimus 

n. sp. in dark soft sandstones and with Chonetes novascoticus}Iall and Spirifer cyclopterus Hall 

in lighter sandstone, Edmunds Hill (localit.ies 1099 C, 1099 ~1), Chapman Township, Aroostook 

County, Maine. Two specimens from the blue siliceo-calcareous grits of the ~1oose River sandstone can not be distinguished from the specimens obtained in the Chapman sandstone. (See 

Pl. V, fig. 30.) Isolated fragments of Tentaculites also occur in a rock full of LeptocfElia 

jlabellites between Detroit and Parlin Pond, Somerset County, Maine. 

· U. S. National Museum, catalogue Nos. 59874 to 59876. 

TENTACULITES cf. T. ELONGATUS Hall. 

Plate XIV, figure 26. 

cf. 1859. ·Tentaculites elongatus. Hall, Paleontology of New York, vol. 3, p. 136, pl. 6, figs. 16-21. 

ShaJy limestone and upper Pentamerus, Lower Helderberg group: Helderberg Mountains and Schoharie, N.Y. 

Additional specimens have since been found which indicate that a probably distinct species 

occurs in the Moose River sandstone fauna. This species is extremely abundant in light-buff 

calcareous quartzites in So1nerset County, along with Leptocmlia flabellites Conrad, Chonetes 

novascoticus Hall var. canadensis Billings; Chonetes antiopus Billings, Leptostroph~a blainvillei 

Billings, and crinoid segments. The Tentaculites here attain a gigantic size, fragments over 

25 milli1neters long and 1.5 millimeters wide at the smaller end being common. These large 

Tentaculites differ from the Chapman form in being much more attenuate, the cone widening 

i milli1neter in a length of more than 10 millimeters. These large forms are even n1ore 

slender than Tentaculites elongatus Hall and may perhaps be regarded as a slender 'Variety of 

that species. · 

Locality: ~Ioose River sandstone, Somerset County, :Maine. 

U.S. National Museum, catalogue No. 59877. 

Comparisons.-The name Tentaculites, scalaris was proposed by Schlotheim for internal 

mold$ of a species of Tentaculites found in Prussia, in drift bowlders of the Baltic Silurian 

Beyrichia-Chonetes limestones. At the same tin1e Schlotheim described Tentaculites annulatus, 

based on complete shells from Gotland. Both the T. annulatus and the T. scalaris of of Schlotheim are now commonly regarded as representing a single species, a Silurian Tentaculites 

s'imilar to the Silurian shells which in England are named T. ornatus Sowerby and which in 

America are called T. niagarensis Hall, T. gyracanthus Eaton, etc. With the Gotlandian T. 

annulatus Schlotheim described a variety of this species in which the rings are more closely 

crowded, from Devonian rocks in Prussia~ The surface, according to Koken, is covered with 

the. usual finer striffi. For this German early Eo-Devonian· shell Koken 1 proposed the name 

Tentaculites schlotheimi. Koken stated that T. schlotheimi was specifically distinct from shnilar 

forms of Tentaculites occurring in the Coblenzian of Altenahr, Kyll, Ems, and elsewhere in 

the Coblenz district, and also from Tentaculites grandis Roemer, from the Silesian Eo-Devonian 

Wurben Valley quartzite, but he did not point out the distinctive characters of these species. 

The Tentaculites from the 'Coblenz district ·are well figured and described by Quensted 2 and 

by the Sandbergers.3 These shells pass under the name Tentaculites scalaris, though they are 

plainly not Schlotheim's species, which is ·a shell with distant and ihequidistant ribs, as was 

pointed out in 1859 by Boll 4 and later by Krause, 5 by Roemer, and by Koken. 

The Chapman shells conform with the brief description of Tentaculites schlotheimi given 

. by Koken. Clarke identified the fossils with the Coblenzian forms of Tentaculites referred to 

1 Deutsch. geol. Gesell. Zeitschr., vol. 41, p. 82, 1889. 

2 Quensted, F. A., Handbuch der Petrefaktenkunde, p. 399, pl. 35, figs. 26-29, 1852. 

a Sandberger, Guido and Fridolin, Die Versteinerurigen des rheinischen Schichtensystems in Nassau, p. 248, pl. 21, figs. 9 a-g, 1856. 

• Boll, Ernst, Ver. Freunde Naturgeschichte Meklenburg Arch., vol. 13, p. 163, 1859. · 

5 Krause, A., Deutsch. geol. Geseil. Zeitschr., vol. 29, p. 28, 187i. 
ARTHROPODA. 285 

by Koken, but the shells here called Tentaculites schlotheimi show the fine horizontal strire 

to be less profuse than in the Gern1an Coblenzian :fonns as figured by the Sandbergers. 

In the A1nerican faunas the nearest species is Tentaculites elongc~tus IIall, from the I-Ielderberg 1 and Oriskany.2 1-Iall's species agree with the Chapman and Detroit fossil in ornainentation, but is n1ore slender and n1ore tapering, and attains greater size than T. schlotheimi. 

Tentaculites scalarijormis I-Iall, 3 from the "Corniferous" lin1estone, is a large, thick, closely 

annulate shell of the type of T. schlotheimi, but is 1nore profusely striate. It comes nearest 

to the Sandbergers' T. scalar1:s (not Schlothein1), fron1 Doblenz. 

ARTHROPODA. 

Class CRUSTACEA. 

Subclass TRILOBITA. 

Genus HOMALONOTUS Koenig, 1820. 

JIOM:AI .. ONOTUS LATICAUDATUS sp. nov. 

Plate XXII, figures 11, 14, 17, 18, 22. 

Cranidium quadrangular, laterally extended at tl~e base into the narrow, ribbon-like fixed 

cheeks. Total width of cranidiun1 one and four-sevenths times the total length. The width 

between the palpebral lobes is decidedly greater than the length of that portion of the cranidium 

between the anterior suture. and the occipital furrow, the proportion being 5:4, thus giving the 

cranidi"un1 above the fix:ed cheeks a rather broad appearance. The glabella is depressed convex, reaching barely above the level of the palpebral lobes. Its demarcation from the rest 

of the cranidiun1 is exceedingly faint, the anterior and lateral furrows are scarcely definable, 

and only when oriented in the proper light. No transverse glabellar furrows are evident. The 

glabella is slightly longer than wide, in the proportion of 20:19. The occipital furrow is narrow and strongly clefmed, extending entirely across the fixed cheeks. The occipital ring is 

slightly narrower than the fixed cheeks. The ring is transverse, and slightly but not conspicuously arched forward in the middle; on the sides the occipital ring swings forward somewhat. The free cheek is nearly straight on its outer border, the eye lobe rises high and abruptly 

frmn the lateral margin, and the cheek is terminated posteriorly .by. a strong, short, but acutely 

pointed genal spine. The free cheeks are detached in all our specimens. They are highly 

inclined to the general plane of the cranidiun1, and were trigonal to trapezoidal in outline, with 

the length (lateral n1argin of the cephalon) two or more times as great as the width. Thorax 

deeply arched, forn1ing nearly a semicircle in transverse section, the height being 0.4 7 of the 

width. The axis or n1iddle lobe is very broad, though ill defined. The axis is limited laterally 

on the individual seg1nents by a slight constriction of the segmtmt and by a small notch or pit 

on the anterior 0) side, similar to the notch or pit on the occipital ring. Between these pits 

the middle lobe of each segment is arched upward; the height of the arch (when unc·rushed) 

is slightly n1ore than one-quarter the distance between the pits. The lateral divisions of .the 

thoracic segment are about one-quarter as wide as the thorax n1easured along its arching 

surface, but when the thorax is viewed from the back the lateral lobes appear much narrower, 

the 1niddle lobe or axis then appearing to absorb three-fourths the total width of the animal. 

The inclination of the lateral pleura of th~ thoracic segment does not exceed 20° from the 

vertical. The extreme outer portion of the lateral segment is spatulate in form and in the 

specin1ens preserved appears to have stood nearly vertical to the horizontal plane of the body. 

Pygidiun1 relatively obtuse, triangular-pentate. The lateral margins are very nearly 

straight lines, forming an angle of 86°, or nearly a right angle. The pygidium is gibbously 

elevated. In lateral profile the 1nedian line of the surface makes an angle of 37° to 40° with 

1 Ho.ll, Jo.mos, Paleontology of New York, vol. 3, p. 13G, pl. G, figs. 10-21, 1859; vol. 5, pt. 2, supplement, p. 6, pl. 94, fig. 14, 1888. 

11 Clo.rko, J. M:., 'rho Oriskany :fauna of Becraft Mountain, Columbia County, N. Y.: New York State Mus. M:em., vol. 3, No. 3, p. 27, pl. 3, 

figs. 8-12, 1!l00. Woller, Stuo.rt, 'l'ho Paleozoic faunas [of New Jersey]: New Jersey Geol. Survey, Paleontology, vol. 3, p. 3G3, pl. 50, figs. 4-5, 1903. 

8 Hall, James, Paleontology or New York, YO!. 5, pt. 2, p. 1Gi, pl. 31, figs. 3-11, 18i9. 
286 FA UN A OF THE. CHAPMAN SANDSTONE OF MAINE. 

the base. The terminus is obtusely subangular. The axis is moderately well defined and 

shows distinctly on the internal molds 11 or 12 annulations, indicating about 13 on the complete surface. The rings are strongly convex and transverse, without any arching forward in 

the 1niddle, and are wider than the interspaces. Posteriorly the axis merges into the smooth 

terminus. The lateral segments, though well defined, are less strongly elevated but broader 

than those of the axis; eight segments can be distinctly counted on the internal mold and on a 

frag1nentary exterior, and if a ninth segment is present it must be exceedingly faint. The 

first ring of the axis is continued latera1ly into the firs~ lateral segment; the eighth ring of the 

axis is continued laterally into the seventh lateral segment. The intervening lateral segments 

and furrows and axial rings and furrows, respectively, do not abut directly against each other. 

The lateral segn1ents continue to the margin and both the lateral and the axial segments are 

devoid of grooving. 

Two or three fragments of clean external molds of the pygidiun1 and fragments of thoracic 

segments indicate that the surface was smooth, devoid of pustules, pores, or corrugations, etc. 

It is barely possible, however, that more· abundant and better n1aterial may show the pustulated 

or pitted ornamentation common in Homalonotus, at least on the cephalon. 

A pygidium of a young speci~en is 21.66 millimeters w1de and is 19 millimeters long (length 

measured on sloping surface). Another fragmentary pygidiun1 was about 60 Inillimeters 

wide and 53 millimeters long. The latter specimen probably represents the usual size, though 

several specimens of small size correspond nearly to th~ small pygidium mentioned. 

Among the more diagnostic characters of the species are the faint demarcation of the glabella; total absence of furrows on the glabella; anterior suture nearly transverse, only ~lightly 

arched; well-marked occipital ring; strong upward arching or gibbosity of the thorax; lateral 

segments of the thorax nearly vertical; pygidium relatively broad, the sides including an angle 

of 86° or very nearly a right angle; surface devoid of spines, and apparently smooth. 

Locality: The species is represented by detached free cheeks, isolated thoracic segments, 

and a few fragmentary pygidia and cranidia supposed to belong to a single species. These 

occur in loose blocks of the Chapman sandstone on Edmunds Hill and 2 miles west of Presque 

Isle Stream, Chapman Township, Aroostook County, Maine. 

U. S. National Museum, catalogue Nos. 59878, 59879, 59880. 

Comparisons.-The species is nearly allied to H. delphinocephalus Green,t.from the Niagara 

group. The Chapman fossil can be easily distinguished from the Silurian form by its broader 

pygidium. Moreover, in the cranidium the anterior suture is nearly transverse and angular 

at the sides in Il: laticaudatus sp. nov., whereas it is ovally arched and curves into the lateral 

or facial suture in Il. delphinocephalus Green. 

The broad pygidium and the great gibbosity of the body distinguish Il. laticaudatus from 

other species. · .• HoMALONOTus v ANUXEl\H Hall. 

Plate XXII, .figures 10, 12, 13, 15, 21. 

1859. Homalonotus vanuxemi. Hall, Paleontology of New York, vol. 3, p. 352, pl. 73, .figs. 9-11 (not .fig. 12). 

Helderberg shaly limestone: Herkimer County and Helderberg Mountains, Albany County, N.Y. 

1888. Homalonotus vanuxemi. Hall, idem, vol. 7, p. 11, pl. 5 B, .figs. 1, 2. 

Helderberg shaly limestone: Albany and Herkimer counties, N.Y. 

not 1903. Homalonotus vanuxemi. Weller, Paleontology of New Jersey, vol. 3 (Paleozoic faunas), p. 321, pl. 39, .figs. 

7, 8; p. 338, pl..44, .figs. 4-7. 

Northwestern New Jersey. 

Besides the Ilomalonotus laticaudatus from Edmunds Hill, the Chapman sandstone fauna 

. contains several. well-:preserved pygidia and abundant fragmental remains of another species 

of Homalonotus occurring 2 miles west of Presque Isle Stream.· This second form I identify 

with Homalonotus vanuxemi Hall. It does not seem to attain the large size of Il. latica1.tdatus 

and is, moreover, easily distinguisp.ed by the narrower and more profusely annulated pygidium. 

t Hall, James, Description of the species of fossils found in the Niagara group at Waldron, Ind.: Indiana Dept. Geol. and Nat. Res. Eleventh 

Ann. Rept., p. 332, pl. 34, figs. 17, 18, 1882. 
ARTHROPODA. 287 

Figures 13 and 14, Plate XXII, represent characteristic pygidia of Il. vanuxemi IIall and H. 

la,ticaudatus sp. nov., respectively, and n1ake plain the distinction between the two species. In 

size, outline, convexity of the pygidia, and occurrence of 14 or 15 annulations on the elongated 

axis and of 1.2 lateral ple'urre, the sn1all specimens conform with the New York I-Ielclerbergian 

fossil. 

Locality: Chapnw,n sandstone, 2 miles west of Presque Isle Strean1 (locality. 1099 J), 

Chap1nan Township, Aroostook County, :Maine. 

U. S. National Muse'un1, catalogue No. 59881. 

Genus PHACOPIDELLA Reed. 

The generic name Phacopidella was proposed by Reed 1 in 1905· to supplant Acaste Goldfuss, 1843, which was preoccupied. The type chosen was Phacops gloclceri Barrancle, from the 

Bohemian etage E2 or middle of the Silurian. The genus Phacopiclella, originally placed near 

Dahnanites, resembles Phacops in having only the hindmost glabellar lobe and furrow well 

developed, the second and first pairs of lateral lobes of the glabella being obscure, though 

present. The cephalon and pygiclium are semicircular or rounded in a broad semiellipse, as in 

Phacops, and are not elongate or spinose, as in Dalmanites. 

Phacopidella differs from Phaeops chiefly in the character of the glabella. In Phacops 

the glabella is tun1id or broadly bulbous in front, and the first and second furrows are merely 

faint scratches. In Phacopidella the glabella is n1ore elongate, resembling in its gross outline 

that of typical Dalmanites. The first and second lateral furrows in .the glabella of typical 

Phacopidella are better developed than in Phacops, occurring as faint furrows rather than as 

. mere scratches, but in the group of Phacopidella anceps Clarke ~he anterior furrows are faint, 

as in Phacops. Finally, the glabella in Phacops is tuberculate; in Phacopidella it is nontuberculate or ra.rely tubercula,te on the frontal lobe only. 

Two well-ma.rked sectiom; are easily demarcated in Phacopidella. Section 1, the group of 

PhacozJidella gloclceri (Barrande) (typical section), in which the ~rst and second pairs of lateral 

lobes are discernible, includes Dalmanites phillipsi Barrande, fron1 et.age D4 (N eo-Ordovician); 

PhacozJs downingi Sowerby, fron1 the Wenlock (middle Silurian); Phacops glockeri Barrande, 

from etage E 2 (n1idclle Silurian); and Phacops pupillus Lake and P. africanus Salter, fron1 

the Bokkeveld (Eo-Devonian). Section 2, the group of Phacopidella ancezJs Clarke, in which 

only the third pair of lateral lobes is developed, the first and second pairs being either entirely 

obliterated or exceedingly faint, includes PhacozJidella nylanderi Clarke, nnd Phacozndella 

clwzJmani sp. nov., from the Chapman sandstone; Phacopidella brasiliensis Clarke, from the 

Lower Coblenzian of Rio Maecuru; and Phacopidella anceps Clarke, fro1n the Oriskany-" Corniferous" transition beds. 

PnACOPIDELLA CHAPMAN! sp. nov. 

Plate XXII, figures 1, 3. 

Cephalon elongate-paraboloid, angular in front·. Length 4.25 millimeters; width 5.5 millimeters; greatest width opposite the occipital furrow. Genal angles broadly rounded. The 

glabella is elongate, expanding slightly in width from the occipital ring forward. The frontal 

lobe of the glabella is much longer than wide; its width is only half the total length of the 

cephalon. The frontal lobe is most tumid between the eyes. Anteriorly it descends, merging 

into the generu.l convexity of the shell. The pol3terior half of the frontal lobe is marked by an 

angulated ridge, which, with the elongation of the cephalon and the gibbous form, seems at first 

to be clue to bilateral compression in the rock; but the presence of a similar ridge in Phacopidella ancezJs Clarke, a flatter species, and the absence of such a ridge in P. brasiliensis, a gibbous 

species, together with the variability in outline and convexity of the cephalon in the different 

species, have led to the belief thn,t the characters indicated are to only a slight extent due to 

compress~on. This angulatt3d ridge dies out over the third glabellar lobe before reaching the 

occipital groove. The first and second glabellar furrows and lobes are totally lacking on the 

clean internal mold. The third pair of furrows are represented as deep transverse pits which do 

1 Reed, F. R. C., 'l'he classification of the Pbacopidre: Geol. Mag., new ser., decade 5, vol. 2, pp. 225, 227, 1965. 
288 FAUNA OF THE CHAPMAN SANDSTONE OF MAINE. 

not quite meet medially, forming an incomplete furrow. The occipital furrow extends across 

the glabella as a wide groove, the ends -of which ~redeveloped ii1to transverse pits of the third 

pair of lateral furrows. Between these two pairs of pits the third glabellar lobes are developed 

as a narrow ring which is somewhat thinner than the occipital ring. The palpebral lobes are 

minute; the eyes are large and strongly elevated. They extend to the midlength or slightly in 

advance of the midlength of the cephalon and occupy a width equal to 0.8 the length of the 

cephalon. The facial structure is f.aint and extends very nearly horizontally fron1 behind the 

eyes, reaching forward but little. The free cheeks are steeply inclined. ·The border is rather thin. 

Size minute. Length 4.25 millimeters; width 5 .. 5 n1illimeters; a n1inute pygidium fron1 

Edmunds Hill, suggesting in its semicircular outline the pygidia of Phacops, Proetus, etc., is 

referred to the present species. The pygidium is 4 millimeters long and 6 1nillimeters wide and 

shows six annulations on the elevated axis. 

Phacopidella chapmani is easily distinguished from all the described species of Phacopidella 

by th~ narrowly elongate glabella, ·the maximum width of which is scarcely half the length of the 

eephalon. The elongate outline of the cepha1on is also characteristic. 

Locality: Chapman sandstone, Edmunds Hill (locality 1099M), Chapman Township, Aroostook County, Mairie. 

U.S. National Museum, catalogue No. 59882. 

Oomparisons.-ln the m.edian angulation or ridge on the glabella the species approaches 

P. anceps Clarke/ from the base of the "Corniferous," or rather the Oriskany-" Corniferous" 

transition beds of Ontario, but is distinguished by having the glabella and cephalon nwre 

elongate, as well as by having the third glabellar lobes proportionately narrower with refer.-

ence to the occipital ring. The transverse pits in the occipital groove of P. anceps are not so 

well'developed as in P. chapmani. 

Clarke 2 has described.a (!ephalon of Phacopidella nylanderi from ~dmunds Hill, the locality where P. chapmani was found. P. nylanderi Clarke as figured and described is entirely 

distinct from P. chapmani/ it is much broader, the glabella is also broader, it lacks the n1edian 

angulation, and the genal angies ·are sharper. 

Genus SYNPHORIA Clarke. 

The geilus Synphoria Clarke .is now made to include all the trilobites 3 differing fron1 the 

typical DaJmanites in having the margin of the cephalon bizarrely ornamented with spines. 

This ornamentation in the various forms previously classed as different genera-Probolium, 

Odontocephalus, Corycephalus, etc.-but now grouped together·in the genus Syll.phoria, n1ay 

consist of a single spine projecting in front of the cephalic rim, or the spine may be a twopronged or three-pronged fork, or the rirn of the cephalon (both front and side) n1ay include a 

row of numerous spines or crenulations. A common feature in all the forms included in Synphoria is the coalescence or tendency to coalesce laterally of the first and second glabellar lobes. 

These fossils also have the genal angles spinose, and the pygidium usually ends rather sharp]y 

or in a spine. Among the several'groups of Dalmanites the Synphorias usually possess the .· 

maximum number of axial segments in the pygidiun1. . 

The Chapman collections include two elongate, acutely ending pygidia representing at 

least one and probably two species of Synphoria. Unfortunately, the cephalon. and the nlarginal ornan1entation are unknown. 

DALMANITES ( ~ SYNPHORIA) a sp. nov 

Plate XXII, figure 8. 

. This species is represented by an elongate pygidium unornamented in internal n1old. It is 

characterized by its depressed convexity, the specimen being nearly flat, and by having the 

axis of the pygidiun1 depressed below the level of the sides. About 12 segments seem to have 

1 Clarke, J. 1\L, As tritobitos do grez de Erere e Maecuru, Estado do Para, Brazil: Mus. nac. Rio de Janeiro Arch., vol. 9, p. 16, pl. 1, fig. 3, 1892. 

2 Clarke, J. M., Some new Devonian fossils: N.Y. State Mus. Bull. 107, p. 166, 1907. 

a Clarke, J. M., The Oriskany fauna'of Becraft Mountain, Columbia County, N.Y.: New York State Mus. Mem., vol. 3, No.3, pp. 16-18, 1900. 

Van Ingen, Gilbert, The Siluric fauna·near Batesville, Ark., pt. 2, Paleontology [trilobites]: Columbia Univ. School of Mines Quart., vol. 23, pp. 

34-74, 1901. Reed; F. C. R., 'l'he classification of the Phacopidm: Geol. Mag., new ser., decade 51 vol. 2, p. 225, 1905. 
ARTHROPODA. 289 

been present on the axis; they are transverse, hardly if at all arching forward. Nine apparently ungroovcd segn1ents n1ay be counted on each side. The apex of the pygidiun1 is acute 

and slightly deflected upward, but whether prolonged into a terminal spine or not can not b~ 

stated, as the extren1e apex is broken off. 

Length (of pygidium) 17 millimeters, width 16.5 millimeters. 

Locality: Ferruginous blocks of the Chapman sandstone on Edmunds Hill (locality 1099 C2

), 

Chapman Township, Aroostook County, :Maine. . 

U. S. National :Museun1, catalogue No. 59883. 

Oomparisons.-The pygidiu.m closely resembles that of the Oriskanian Dalmanites (Synphoria) stommatus var. convergens Clarke, t from Becraft :Mountain, N. Y., but in that variety 

the outline is slightly less tapering and the axis is n1ore profusely annulate. 

Dalmanites (Synphoria) met~ki· Walcott, 2 from the Lower Devonian limestone of the Eureka 

district, Nev., is similar, but ha,s the pygidium slightly less ac11:te and the. posterior extremity 

more strongly deflected upward. . 

DALMANITES ( ~ SYNPHORIA) fJ sp. nov. 

Plate XXII, figure 5. 

In a second species of Synphoria the pyg!diun1 is n1ore gibbous and the axis is elevated 

above the sides. Twel·ve or thirteen· annulations may be counted ih the· axis. on the exterior; 

the last two annulations are not discernibly in1pressed ·on the interior. The axial rings arch 

forward prominently. Nine segments tnay be counted on each side; these are wid~r than the 

interspaces. The forward lateral segments of the pygidiun1 are grooved, but the grooves are 

visible only on the ~xte~ior mold, and even there are exceedingly faint. The surface is devoid 

of tuberculations. In this as well as in the preceding form the n1argin is entire, and the posterior termination of the pygidiuni is hardly at all deflected upward. 

Length of pygidh.1n1 12.66 millimeters; width, approxin1ately 12 millimeters. 

Locality: Chaptnan sandstone, with Spirifer cyclopterus Ha.U, west side of Edmunds Hill 

(locality 1099M), Chapman Township, Aroostook County, Maine. 

U.S. National Museum, c.atalogue No. 59884. 

OomzJarisons.-This species is closely allied to Dalmanites (? Synphoria) alpha, from which 

it is distinguished by its stronger convexity and by having its axial rings n1ore strongly arched 

in the n1iddle. The differences may, however, be due to deforn1ation in the rock, and the 

specimens may possibly repr.esent the same species. · 

The fossil is similar to the Eo-Devonian Dalmanites (Synphoria) concinnus I-Iall,3 fron1 the 

Schoharie grit, Schoharie, N. Y., in outline, number of segments, arched axial rings, and nondeflected apex, and in having .the lateral segments broad and flat, but it lacks the welldemarcated border of the New York species, in which, n1oreover, the lateral segments are n1ore 

strongly grooved than in the Chapman sandstone fossil. 

OSTRACODA. 

By E. 0. ULRICH. 

Family BEYRICHIIDJE. 

Genus CTENOBOLBIN A Ulrich. 

CTENOBOLBINA0) CORNUTA n. sp. 

Plate XXVII, figures 17-19. 

This species is represented· by a single specin1en retainip.g both valves. These, though 

widely opened, are yet joined along their cardinal edges. The length is about 1.8 millimeters, · 

height 1.1 millimeters, greatest thickness through middle of joined valves probably about 0.9 

n1illimeter. · ' 

1 Clarke, J. l\L, Now York State l\fus. l\fem., vol. 3, No.3, p. 19, pl. 2, fig. 4, 1900. 

· 1 Soo Hull, Jumos, uncl Clarke, J. l\f., Paleontology of New York, vol. 7, p. 32, pl. 11 A, figs. 28-30, 1888. 

3 Idem, p. 30, pl. 11 A, figs. o, 10, 11, 1888. 

50245°-No. 89-16--19 
290 FAUNA OF THE CHAPMAN SANDSTONE OF MAINE. 

Surface of. valves moderately and rather evenly convex except in the posterodorsal quart~r. This contains a small but prominent conical node, located just within the dorsal edge 

and about one-fourth of the total length of the valves in front of the posterior extremity. 1 On 

the anterior side this node is outlined by a narrow curved sulcus which dies out before reaching halfway across the valve. The outline of the valves is subovate, straight along the dorsal side, and slightly narrower in front than behind. The anterodorsal angle terminates in 

a short spine, but the other extremity of the hinge line seems obtusely angular or narrowly 

rounded. A narrow border on the free edges: This overhangs and in a side view conceals the 

true contact rims. 

Otenobolbina · (?) cornuta is characterized by an unusually simple type of carapace. The 

main sulcus alone remains, and this is much shorter than is the· corresponding depression in 

nearly all of the species previously referred to the genus. The conical node also is situated 

nearer the dorsal edge than is the corresponding node in all of the other species of the genus in 

which anything of the kind has been observed. The brevity of the sulcus and the dorsad position of the node which, moreover, is an exceptionally prominent feature, will therefore readily 

serve in recognizing the species. There should be n·o trouble in distinguishing it fr01n the 

associated species of Beyrichia. 

Formation and locality: Chapman sandstone, right bank of South Branch of Presque Isle 

Stream, at end of Tweedy Road, Chapman Township, Aroostook County, Maine-. 

Genus ZYGOBEYRICmA ~· gen. 

This new generic name is proposed for a group of large Beyrichiidre that seems to represent 

a departure from the typical beyrichian stock at a time when other considerable changes in 

the fa.mily were inaugurated. So far as known the oldest of these species is an undescribed 

form found in the late Silurian Tonoloway limestone of Maryland. Three other species occur 

in this early Devonian fauna, one of them being identified with a species described from the 

Lower Devonian rocks of Devonshire, England, by Jones and Woodward under the name 

Beyrichia devonica)· the other two are apparently new. At least one and probably two more 

species having the same generic fe~tures are included in unworked collections in the United 

States National Museum, procured, like the others, from rocks lying near the Silurian-Devonian 

boundary in eastern North America. 

Judging from this representation the new genus is distinguished from Beyrichia (1) by the 

partial or complete obsolescence of the posterior lobe and (2) by the excessive development 

of the ventral junction of the median and anterior lobes. These peculiarities, especially on 

.account of the looplike form of the confluent lobes, impart an aspect suggestive more or less 

strongly of species now referred to the B. ungula section of the genus Bollia. That this 

resemblance to Bollia is more apparent than truly· indicative of genetic relationship seems 

reasonably certain from the negative fact that intermediate stages are unknown, and more 

particularly from the positive fact that· in this proposed generic group there is scarcely a suggestion of the marginal ridge that from the Ordovician to the Middle Devonian was always a 

more or less clearly developed feature in species of Bollia. On the other hand, .the beyrichian 

affinities of Zygobeyrichia are clearly established by comparing those specimens of the new 

genus in which the posterior lobe is more noticeable than usual with such typical Silurian species 

of Beyrichia as B. lcloedeni and B. buchiana. The lobes in such specimens-one is shown in 

Plate XXVII, figure 12-are so readily correlatable with those of typical species of Beyrichia 

that detailed analysis seems unnecessary. When the range of these COlnparisons is extended 

so as to include the other species of the new genus, it will become increasingly evident that the 

only essential departures from the beyrichian stock are those mentioned in the opening sentence 

1 The final decision as to ~hich of the two ends is the anterior in these small bivalved crustacea is yet a matter of the future. In the present 

work it was thought advisable to continue the method of orientation defended and employed by Ulrich and Bassler (U.S. Nat Mus. Proc., vol. 351 

pp. 277-340, 1909). To avoid confusion it should be understood that good authorities, among them Jones and Bonnema, have commonly denominated as posterior the end here described as anterior. However, the criteria followed by them appear not to have led to uniform results. 
ARTHROPODA. 291 

of this paragraph. The obsolescence of the posterior lobe is more or less clearly noticeable in 

all, being carried to an extreme in Zygobeyrichia extrema, and the strong development of the 

ventral part of the loop remains a constant feature. 

Comparative studies of the Beyrichiidre clearly show that of the three lobes always found 

in the genus Beyrichia the posterior one is the least stable. It became particularly variable 

with the beginning of the Devonian when the representatives of the type of structure that prevailed so abundantly in the Silurian, and to which the genus has been confined by Uhich and 

Bassler/ were reduced to a few in part aberrant species. In most of these surv~vors the posterior 

lobe tends to obsolescence, while in the predon1inating Devonian and Mississippian representatives of the family, .chiefly included in the genera Hollina, Treposella, and the new Zygobeyrichia, this lobe is commonly weak or quite. effaced. 

A similarly modest developraent of the posterior lobe is observed in nearly all of the species 

of IGoeclenia, another genus tha.t attained its acme in the latest Silurian and early Devonian. 

The swelling of the dorsal part of the median lobe, that is so well shown in th.e three species 

representing Zygobeyrichia in the Chapman sandstone, likewise recalls Kloedenia. These 

similarities, however, though suggesting genetic relationship, seem to indicate generic divergence fr01n a common beyrichian root rather than specific modifications within the same generic 

group. . · 

Zygobeyrichia apicalis n. sp. has been selected as the genotype. 

ZYGOBEYI~ICHIA DEVONICA (Jones and Woodward). 

Plate XXVII, 'figures 1-6. 

1889. Beyrichia devonica. Jones and Woodward, Geol. Mag. Dec. 3, vol. 6, p. 386, pl. 9, figs. 3a-3d (? 4~ 5). 

This well-marked species is represented in the collections by four or five specimens that 

closely simulate the British (Devonshire) specimens on which Jones and Woodward founded 

the species. The middle lobe extends well-nigh to the dorsal edge and is inflated and somewhat 

conically prominent in its upper part. Beneath this the relatively attenuated though high 

ventral part curves forward to join the less sharply defined anterior lobe, the two forming a loop 

of the kind commonly developed in species of Beyrichia like Beyrichia buchiana and B. kloedeni. 

In the present species, howeve:r, the posterior lobe is so imperfectly developed that the loop 

formed by the junction of the Jnedian and anterior lobes is unusually conspicuous. In consequence the general aspect of the valves 1s decidedly suggestive of Bollia, particularly of species 

of the B. ungula section of the genus. 

The ventral pouch of. the female form of the species has been observed in only a single examplG. (See Pl. XXVII, fig. 4 .. ) This shows the pouch to be uncommonly elongate, elliptical 

in form, and its longer axis more nearly parallel with the dorsal edge than in any species of 

Beyrichia or any other species of Zygobeyrichia known. In both respects the pouch of Z. 

clevon'ica, approaches the same structure in the nearly contemporaneous Mesomphalus l1.artleyi 

Ulrich and Bassler. 

Some variability in dimensions and _forn1 .is observable among the Chapman sandstone= 

Ostracoda, here regarded as· agreeing too closely to be distingui;;hed even as a variety from the= 

best of the British specimens originally figured and described by Jones and Woodward under· 

the name B. devonica. Though much of this .apparent variability doubtless is attributable to 

distortion of the valves subsequent to burial, it yet appears that as a rule the posterior ridge is. 

a lesser feature, and the anterior ridge less sharply defined on its anterior side in these American 

species than in the Devonshire types of the species. It is to be remarked, however, that'both 

of these ridges are no less obscurely developed and the anterior end equally obtuse in specimens. 

originally, and also in others subsequently, referred to B. devonica by Jones himself. 

It is of interest and possibly of str~tigraphic significance to note here that the older Pembroke formation contains an abundance of more or less crushed valves of an ostracode that, in 

the features mentioned, agrees even better than these Chapman sandstones specimens with the· 

1 Ulrich, E. 0., and Bassler, R. S., Preliminary revision of the Beyrichlidre, with descriptions of new genera: U. S. Nat. Mus. Proc., vol. 35, .. 

pp. 277-340, 1909. ' 
292 FAUNA OF THE CHAPMAN SANDSTONE OF MAINE. 

a~terodorsally angu~ar British and Turkish specimens· originally referred to B. devonica by 

Jones and. Woodward. Possibly two closely allied species have been united under this name. 

The length of the specimens commonly varies between 2.5 and 3.5 millimeters, the average 

bf}ing little more or less than 3 millimeters. Allowing for distortion by pressure, the height is 

approximately half the length. 

Formation and locality: Chapman sandstone, right bank of south branch of Presque Isle 

Strean17 at end of Tweedy road, and Edmunds Hill, Chapman Township, Aroostook County, 

Maine. 

ZYGOBEYRICHIA APICALIS n. sp. 

Plate XXVII, figures 11-16. 

This fine species is related to the associated Beyrichia devonica. It is readily distinguished 

by its relatively shorter form, and because of the fact that the dorsal part of the median lobe is 

even more prominent and therefore also more distinctly separable from the lower curved part 

. of the loop. Furthermore, the base of the median lobe does not reach the dorsal edge, the lobe 

as a whole appearing, in a side view of the valves, as occupying a position nearer the middle. 

An10ng other differences shown in the illustrations it should be noted tha~ the dorsal extremity 

{)f the posterior lobe is more prominent and lies nearer the postdorsal angle. Also, that the 

flattened border on the free edges, especially in the testiferous specimens, is more distinctly 

developed. 

Two excellently preserved valves-both right and left-of the female form of this variety 

show the ventral pouch .to be of medium size and located wholly in the posterior three-fifths of 

the valves. Its thickest part projects a trifle beyond the ventral edge. The whole surface of 

the pouch is minutely and closely punctate, forming a n·eat reticulation in which the arrangement of the punctm in longitudinal series predominates.. This network extends some distance 

upward on the anterior lobe, but dies out long before reaching the dorsal edge. A similar punctation crowns the swollen part of the r.aedian lobe. The remaining parts of the surface of the 

valve are s1nooth: 

Length of carapace 2.5 to 3.2 millimeters, with tlie average but little under 3 n1illimeters. 

Height somewhat greater than half·the length, th~ two measurements commonly in the ratio 

of 3 to 5, respectively. Greatest thickness of complete carapace approximately equal to the 

height. 

No other described species seems so closely allied as B. devonica, from which it has been distinguished. Further comparisons, therefore, are deemed unnecessary. 

Formation and locality: Chapman sandstone, right bank of south branch of Presque Isle 

Stream, at end of Tweedy road, and 2 miles west of Presque Isle Stream, Chapman Township, 

Aroostook· County, J\.faine. ' 

ZYGOBEYRICHIA EXTREMA n. sp. 

Plate XXVII, figures 7-10. 

The specimens for which this new specific name is proposed agree among themselves in 

the almost complete obsolescence of the posterior lobe. The main sulcus is centrally situated, 

deep, and extends from the dorsal edge at least three-fourths of the distance to the ventral 

margin. The ridge corresponding to the usual. median lobe of Beyrichia is high, somewhat 

. expanded above, but on the whole of moderate thickness. Below it joins, by means of a looplike connection, the base of the anterior lobe. The latter is large, thick, and sharply defined 

on its inner side by the deep sulcus, but on its outer side merely slopes somewhat rapidly to the 

level of the valve margin. Remains of the test indicate that the elevated parts of the outer 

surface are covered with small pustules. Ventral pouch of female high, bulbous, strongfy 

oblique with respect to the hinge line, and wholly con:fin~d to the posterior half 

Length of a well-preserved left valve 2.3 millimeters, greatest height 1.5 millin1eters, 

grea~est thickness (to summit of median lobe an~ vent~al part of loop) about 0.9 n1illimeter. 
VERTEBRATA. 293 

From its congeneric associates in the Chapman sandstone Zygobeyrichia extrema is distinguished at once by its shorter and n1ore gibbous form, and especially by the narrowness of 

the space between the bulbous median lobe and the posterior margin. From species of Kloedenia 

it differs conspicuously in the practically complete loss of the posterior lobe, the greater depth 

and length of the sulcu~, and the ventral prolongation, prominence, and looplike confluence of 

tho n1eclian and anterior lobes. Compared with species of Beyrichia the total obsolescence 

of the posterior lobe and the great prominence and strength of the ventral loop modify its 

general expression so greatly that confusion seems almost impossible. _ 

Formation and locality:· Chapman sandstone, right bank of south branch of Presque Isle 

Stren.m, at end of Tweedy road, Chapman Township, Aroostook County, Maine. 

VERTEBRATA. 

ClasS AGNATHA Eastman. 

Order ANTIARCHA Eastman. 

Family ASTEROLEPIDlE Traquair. 

Genus ASTEROLEPIS Eichwald. 

ASTEROLEPIS CLARKE! Eastman. 

Plate XXII, figure 19. 

1907. Asterolepis clarkei. Ea.stman, New York State Mus. Mem. 10, p. 40, pl. 7, figs. 7, 8. 

Chapman sru1dstone: Chapman I,lantation, Aroostook County, Maine. 

The single specimen of this interesting fossil found in the Chapman sandstone was submitted for identification to Dr. Charles R. Eastman, who kindly reported as follows: 

Tho specimen you have sent me, ru3 farM one can determine from ita general configuration, proportions, and style 

of ornrunentation, may be regarded with rea.sonable confidence M one of the dorsomedian plates of the imperfectly 

known Ostracophore which ha.s been described from the srune horizon-Asterolepis Clarkei. Although somewhat smaller 

thru1 the holotype, and with finer and more closely crowded stellate tubercles, the presence of a distinct median longitudinal ridge ru1d the laterally sloping surface on either side of it are characteristics which render an a.ssociation with this 

unique form fairly certain. 

The dimensions of the original speciinen were described as follows: ''Extreme width of 

the plate is slightly in excess o:f the total length, which amounts to 4 centimeters in the type 

specimen.'' · 

The present specimen is about 2.5 centimeters long and about 2 centimeters wide, and the 

tubercles a1~e smaller than those of the type specimen in the same proportion. 

Locality: Chapman sands't,one, 2 miles west of Presque Isle Stream, Chapman Township, 

Aroostook County, Maine. · 

U.S. National Museum,.c~~talogue No. 77,09. 

PLANT )E. 

In some of the strata ot the Chapman sandstone traces of plants have been discovered, but 

specimens which show sufficient characters to indicate possible relationship with described 

forms are rare. A few small branching stems have the habit of Psilophyton princeps Dawson. 

The material does not, however, show the spinose processes that appear on good specime~s of 

that species. Other fragment:3 are woody stems several inches in length, but these display no 

characteristic ha~it of growth, ornamentation, or, so far as is apparent, cellular structure. In 

suggesting a general resemblance in habit of some of the fragments to Psilophyton I do not intend 

any identification with Dawson's genus. Too often the name Psilophyton princeps Dawson and 

the generic name Psilophyton have been used as common receptacles for fragmental plant 

remains of the general Psilophyton aspect. David White~ has indicated that plant remains of 

this general expression belong to a diversity of genera. 

1 Smith, G. 0., and White, _David, 'fhe geology of the Perry Basin in southeastern Maine: U.S. Geol. Survey Prof. Paper 35, pp. 58 et seq., 1905. 

APPENDIX~ 

AGE AND CORRELATION OF THE CHAPMAN FAUNA. 

In the preliminary report on the Chapman fauna its general affinity with the later phase 

of the American Helderbergian fauna was announced,! and attention was also directed to the 

presence of species linking it with corresponding faunas of England and other European countries. The detailed study of the species described in the present. volume sufficiently demonstrates these correlations. It remains to summarize the nature of this·evidence and to make the 

correln.tions more precise. 2 

In making an estima,te of the correlation of the Chapman sandstone with outside formations, 

the greater importance attaches to the species recognized in other ,geographi~ areas;· and in 

order to decide whether 1two distinct horizons are represented, the list of species common to both 

is of first importance. · 

1. The following species occur in both divisions of the Chapman sandstone-the presumably 

lower horizon of Presque Isle Stream and the country west thereof, and the higher horizon 

about Edmunds Hill: ' 

Orbiculoidea discus Hall (Hellderbergian). 

Chonetes striatissirous sp. nov. 

Rensselaeria mainensis Williams: 

Spirifer concinnus Hall (Held,arbergian). 

Nucleospira ventricosa Hall (Helderbergian). 

Paleoneilo mainensis Clarke. 

Paleoneilo mainensis var. umbonata var. nov. 

Prcavicula oblonga (Hall) (Helderbergian). 

Plectonotus trilobatus (Sowerby) (Silurian and Devonian). 

Tropidodiscus obex Clarke. . 

Holopea (Auriptygma) beushauseni Clarke. 

Homalonotus laticaudatus sp. nov. 

Tentaculites schlothein1i Koken (Taunusian). 

?Polypora cf. P. lilrea Hall (Helderbergian). 

?Ostracodes (several species). 

2. Species of the Chapman sandstone listed fron1 other localities are· as follows: 

Orbiculoidea discus Hall (Helderbergian). 

Leptostrophia perplana (Conrad) ("Corniferous" to 

Chemung). 

Including L. planulata Hall, the commonest Chapman 

form (Helderbergian). 

Leptrena rhomboidalis Wilckens (Trenton to Mississippian). 

Schuchertella deformis (Hall) (Helderbergian). 

Hipparionyx unguiformis Conrad (Oriskany). 

Chonetes novascoticus Hall (Aymestry to Ludlow faunas). 

Dalmanella planiconvexa Hall (Helderberg to Oriskany). 

Dalmanella cf. D. circulari3 (Sowerby) (Taunusian to 

Lower Coblenzian). 

Stenoscisma formosa Hall (Helderbergian). 

:Eatonia singularis (Vanuxem) (Helderbergian). 

Cyrtina rostrata Hall (Oriskany to "Corniferous"). 

Spirifer concinnus Hall (Helderbergian). 

Spirifer cyclopterus Hall (Helderberg to Oriskany). 

N ucleospira veil.tricosa Hall (Helderbergian). 

Meristella cf. 1\f. bella Hall (Helderbergian). 

Grammysia acadica Billings (late Silurian). 

Telllnites gibbosa var. kayseri Beushausen (Lower 

Coblenzian). 

Tellinites gibbosa var. crassa Beushausen (Lower Coblenzian). 

Nuculoidea cf. N. aquisgranensis Beushausen (Lower 

Cob I enzian) . 

Megambonia (Preavicula) oblonga Hall (Helderbergian). 

Cypricardella cf. C. bico~tula Krantz (Siegen graywacke). 

Plectonotus· trilobatus (Sowerby) (late Silurian to Coblenzian). 

Crelocaulus planogyrata Hall (Helderbergian). 

Homalonotus vanuxemi Hall (Helderbergian). 

Pleurodictyum problematicum Goldfuss (Gedinnian to 

Coblenzian). 

Tentaculites schlotheimi Koken (Taunusian). 

Cornulites serpularis Sc.hlotheim (Silurian and Lower 

Devonian). 

Polypora lilrea Hall (Helderbergian). 

Polypora psyche Billings (Oriskany). 

1 Williams, H. S., U. S. Geol. Survey Bull. 1G5, pp. 82 and 88, 1900. See also Am. Jour. Sci., 4th ser., vol. 14, pp. 203 et seq., 1900. 2 Whilo correcting the proof shoets of this paper I have received Clarke's" Conceptions regarding the American Devonic" (New York State 

Mus. Bull. 177, pp. 115-133, 1915). It should be noted that the manuscript of this paper was completed five years ago and that no attempt is 

now made to refer to the large amount of literature bearing upon many points herein discussed which has been published since 1910.-H S. 

WILLIAMS, October, 1915. 

295 
296 FAUNA OF THE CHAPMAN SANDSTONE OF MAINE. 

Of the species common to both horizons of ·the Chapman sandstone (list 1) those posi.tively 

identified with previously described American species whose horizon in the New York section is 

definitely known are Helderbergian; these species number 5 out of the 14listed. None' of these 

con1mon species is recorded in America· from any horizon known to be distinct from the Helderbergian. Of the described species with which specimens of the Chapman sandstone have been 

identified (list 2, above), 12 are reported from only the Helderbergian of North America, 1 is 

reported from the "Corniferous," 2 are common to the Helderberg and Oriskany, 3 come fr01n 

strata above the Helderberg, 1 from s~rata below the Helderberg, 1 from the Silurian, and 9 

frorri European localities in the Lower Devonian. Removing the 9 European species from the 

30 listed leaves 21 species, of which 15 occur in the Helderberg of America; 6 appear in formations 

above the Helderberg, 4 of which are Oriskany species. The distribution of the species throughout the Chapman sandstone and the identifications with described species make clear the 

correlation with the general Helderbergian fauna. A few species appear which were not present 

in the typical Helderbergian of North America, though they were present in the following 

Oriskany. 

3. The following species recognized in the Chapman sandstone signify affinity with eastern 

transatlantic faunas: · 

Dalmanella cf. D. circularis (Sowerby). 

Tellinites gibbosa var. kayseri (Beushausen). 

Tellinites gibbosa var."crassa (Beushausen). 

Nuculoidea cf. N. aquisgranensis (Beushausen). 

Cypricardella cf. C. bicostatt~la (Krantz). 

Plectonotus trilobatus (Sowerby). 

Pleurodictyum problematlcum Goldfuss. 

Tentaculites schlotheimi Koken. 

Cornulites serpulluius Schlotheim. 

4. Other species listed by Cl'arke 1 are the following: 

Platyceras kahlebergensis B"eushausen (Spirifer sandstone, 

Harz). · · 

Loxonema cf. L. funatum A. Roemer (Spirifer sandstone, 

Harz). 

Holopea beushauseni Clarke (see Macrocheilus?) (Spirifer 

sandstone). 

Modiomorpha vulcanalis Clarke (see Goniophora cognata 

and Modiomorpha elevata) (Lower Coblenzian). 

Grammysla modlomorpha Clarke (Upper Coblenzian). 

Spirifer macropleuroides Clarke (Lowest Devonian, Harz 

and Bohemia): 

Chonetes aroostooki Clarke (Tilestone and Spirifer sandstone). 

Leptostrophia magliifica parva Clarke (Coblenzian). 

Dalmanella drevermanni Clarke (Coblenzian) . 

. Ccelidium tenue Clarke (Spirifer sandstone). 

Eotomaria hitchc?cki Clarke (Tilestones and Spirife) 

sandstone). 

Pterinea cf. P. fasciculata Goldfuss. 

Paleoneilo mainensis Clarke (Coblenzian). 

Nucula cf. N. krachtre A. Roemer (Coblenzian). 

Paleosolen simplex Maurer (Coblenzian). 

Spirifer subcuspidatus lateincisus Scupin (Coblenzian). 

Spirifer cymindis Clarke (Upper Coblenzian). 

Spirifer cymindis var. sparsa Clarke (cf. Coblenzian). 

From the foregoing lists it is evident that this fauna is intimately related on the one hand 

to the Tilestone fauna of England and on the other hand to the so-called Hercynian fauna of the 

Continent, the opinion expressed in 1900,2 after a preliminary study of this fauna, being abundantly confirmed. ' . 

This faunal relationship must not be confused with either formational or chronologie 

identity. The fact that the same species occur in beds on the two sides of the Atlantic indicates 

that the sediments of the two regions were deposited within the period of time during which 

the speci~s lived together in a faunal community; but it does not necessarily follow that there 

·was, at the exact time of deposition of the Chapman sandstone, an open-sea connection between 

the two areas, through which the species were ·distributed by migration. 

The conclusion advanced above is supported by the presence of identical species on both 

sides of the Atlantic, but, on the other hand, there is abundant evidence of unlike species distinguishing the Chapman fauna from both the Tilestone and the Coblenzian faunas of Europe. 

On comparing the Chapman fauna with transatlantic faunas, it should be noticed that the 

fauna which succeeds the Tilestone (Downtonian) of Great Britain is of brackish-water habitat 

(the Old Red sandstone), and that in northern Europe the fauna preceding the Taunusian and 

the Coblenzian is the Gedinnian, which is not directly represented in America .. 

1 Clarke, J. M., New York State Mus. Bull. 107, pp. 153-291, 1907. 

2 Williams; H. S., Silurian-Devonian boundary in North America; 1. The Chapman sandstone fauna: Am. Jour. Sci., 4th ser., vol. 9, pp. 203-213, 

March, 1900. 
APPENDIX. 297 

Similar differences are observed in the changes marking the sections of Gaspe and New 

York. Before· Middle Devonian time brackish-water and land areas had developed along the 

eastern border of North America (New Brunswick and Nova Scotia), while over New York 

marine sedin1entation was in progress. The fact that the marine faunas preceding this continental uplift have comn1on species on both sides of the Appalachian divide and in Europe 

shows evidence of a connection whereby species could pass from one sea to the other. In 

Middle Devonian time, however, the faunas of New York and north continental Europe were 

evidently developed in separate basins. 

These facts indicate that the elevation which brought in the Old Red sandstone sedimentation in central and northern Great Britain was connected with the upward lifting in eastern. 

North America, but that the change from marine to land conditions in Great Britain may not 

have been quite contemporaneous with the corresponding change marking the passage from 

marine beds to brackish-water sandstone in the eastern provinces of Canada. It is not surprising, therefore, to find the faunas of this transition period in the marine region showing 

closer affinity with the Lower Devonian fitUnas of Europe than with the typical Lower Devonian 

faunas of New York; nor is it surprising to find the European Lower Devonian faunas carrying 

nutny species which are present in the New York Middle Devonian, these species making their 

way into New York across the Atlantic in Lower Devonian instead of Middle Devonian time 

and finding expression in these transition faunas of the eastern provinces. The remarkable 

combination of species in the more recent of the limestone blocks in the breccias of St. Helens 

Island 1 confirms this view. . 

In northern Europe the greatest faunal change in the early true Devonian appears to have 

taken place at the horizon separating the Upper Coblenzian from the Lower Coblenzian beds. 

As Frech 2 notes, the genera Tropidoleptus, Rensselaeria, and Cypricardella are lacking· in the 

"zone of Spirifer paradoxus," although they are common in the lower beds, and Orthis (Dalmanella) circularis Sowerby is also found in the lower but not in the upper beds. The upper 

beds, however, contain n1any species which range below into the Lower Coblenzian; and the 

marine faunas, e.ven with change of species, do not indicate so much a breaking up of the rr:arine 

fauna as an introduction of new types and departure of old types with the advance in the 

succession. For purposes of correlation between the Europ~an and American ~ections, it 

should ·be remembered that the species in the Chapman fauna which are identical with the 

European forms belong to the faunas which are well developed before the beginning of the 

Upper Coblenzian, rather than to the fauna conspicuous ·after that time. 

From. both the European and the American relations of the Chapman fauna it seems to 

be strictly Lower Devonian; ·it presents close affinity with the Helderbergian fauna of New 

York, but shows a greater rnixture of European types than the typical Helderbergian. In comparison with the northern Europe section, the Chapman fauna shows affinity with the Lower 

Devonian, particularly with that portion of it below the Upper Coblenzian. It is a later fauna 

than the Tilestone or Downtonian of Great Britain or the terminal marine fauna of Aris"aig, 

Nova Scotia.· · 

If in place of examining the fauna as a whole we selec.t for comparison special biologio 

groups of species, the result points in the same direction. 

The biologic group presenting the .greatest number of species recognized as identical with 

species already registered is that of the brachiopods. Of these 28 species are listed in this 

report, and 19 of them are identified with species already described. The following species 

are listed by Schuchert 3 as restricted to the Helderberg: 

Orbiculoidea (Roemerella) discus Hall. 

Schuchertella deformis (Hall). 

Stenocisma formosa Hall. 

Eatonia singularis (Vanuxem). 

Spli·ifer concinnus Hall. 

N ucleospira ventricosa HalL 

Meristella cf. M: bella Hall. 

1 Williams, H. S., On the fossil ratinas of the St. Helens breccitJS: Roy. Soc. Canada Trans., 3d ser., vol. 3, pp. 205-246, 1910. 

~Frech, Fritz, Lethrea palreozolca, vol. 2, p. 151, 1897. 

a Schuchart, Charles, A synopsis of American fossil Brachiopoda: U.S. Gaol. Survey Bull. 87, pp. 43 et seq., 1897. 
298 FAUNA OF THE CHAPMAN SANDSTONE OF MAINE. 

One species is exdusively Oriskany: 

Hippaiionyx. unguiformis Conrad \=H. proximus Vanuxem). 

The following species range through both the Helder~erg and the Oriskany: 

Leptrena rhomboidalia Wilckens. Cyttina rostrata Hall. 

Dalmanella planiconvexa Hall. Splrifer cyclopterus Hall. 

Thus 12 of the previously registered species of Brachiopoda oelong to the·known Helderberg and Oriskany of America (·as known in 1897)'. In Schuchert's revision 1 of the faunas in 

1900, the species listed as· strictly Helderbergian were still so restricted. I conclude, therefore, that the evidence furnished by the brachiopods strongly indicates the same fauna which 

characterized the deposits of Helderbergian age in the interior, with admixture of species belonging to an arenaceous phase of the deposits which was of later expression in the interior, and 

that. the Chapman fauna is to be correlated with the Helderbergian fauna of the interior seas. 

Tlfe species of brachiopods which constitute the most conspicuous part of the faunas collected in .the Chapman sandstone are as .follows: 

Rensselaeria mainensis. 

Spirifer sparsus. 

Spirifer concinnus. 

Spirifer cyclopterus. 

Chonetes novascoticus. 

Chonetes striatissimus. 

This combination is decidedly distinct from any reported we~t of Hudson River in North 

America. Although Spirifer concirmus and S. cyclopterus are well represented in the Helderbergian faunas ·of New York, Maryland, and Virginia, S. concinnus is not reported from the 

interior North American localities of that fauna. The genus Rensselaeria is represented in 

both the Helderbergian ~:h.d the Oriskanian faunas, but the three species of the Helderbergian 

fauna of interior North America are restricted in range to ~the outcrops of eastern New York. 

The particular species which. is found abli'ndantly in the Chapman sandstone shows affinity 

with the European Rensselaeria strigice1J,~ in ·possessing a distinct cardinal area, a feature believed 

to be an early character of the race. But whether or not it is associated with an early stage of 

evolution, the dominance of this character places the species evolutionally· at a time horizon 

different from that of the Oriskaniail fauna of New York, in -\yhich the dominan't characters of 

th~ genus are specifically distinct. The area of the pedicle valve appears to be present in small 

specimens,. but it is conspicuous only in large specinlens in which the shell substance is greatly 

thiekened about the beaks and does not show in casts .of the interior of shells· showing both 

valves, though single shells show the area in the molds of the interior of pedicle valves. The· 

Chonetes are of a type not seen in the Helderbergian fauria of the interior, thougH they are 

present in the still earlier Silurian. This type appears in the Arisaig succession; 

Of the Chapman brachiop9ds the following identified species are listed also by J. M. Clarke 

in other faunas east of Hudson River: · · · · 

rLeptostrophia perplana (Conrad) (as L. blainvillei (Billings)), from the Gaspe sandstone. 

Leptrena rhomboidalis \Vilckens, from the St. Albans, Ca.pe Bon Ami, Grande Greve, and Dalhousie formations. 

Hipparionyx unguiformis (H. proximus Vanuxem), from the Grande Greve and the Moose River sandstone. 

Anoplia nucleata Hall, from the Grande Greve beds. 

Cyrtina rostrata Hall, from the Grande Greve beds. 

Spirifer cyclopterus Hall, from the Grande Greve beds. 

Nucleospira ventricosa Hall, from the Grande Greve beds and St. Albans beds. 

Regarding the form listed above as Leptostrophia perplana, examination of the various 

forms of the perplana type found in the Helderberg and Oriskany fauna seems to indicate that 

the size, slight differences in outline, and ·apparent differences in fineness of the strire are not 

constant, and I have adopted perplana as a specific name, recognizing such forms as magnifica 

of Hall and irene, tullia, and. blainvillei of Billings as local varieties. · In correlation, therefore, 

Clarke's identification of magnifica and tullia brings the form listed in this volume in the Chapman fauna among those listed by Clarke from the Grande Greve and St. Albans beds. Therefore seven of the specific·aUy identified species of brachiopods of the Chapman sandstone occur 

also in the Qrande Greve beds of Gaspe Peninsula. 

1 Schuchart, Charles, Lower Devonic aspect of the Lower Helderberg and Oriskanv formations: Geol. Soc. America Bull.. vol. 11, pp. 241-332, 

1900. 
APPENDIX. 299 

There are fewer of the Oriskanian species in the Chapman fauna than in the Grande Greve 

fauna, and the evidence seems to indicate a somewhat earlier stage for the Chapman than for 

the Grande Greve. The community ·of characteristic species, however, indicates close association of the two faunas. 

This brachiopod evidence leads to the conclusion that the Chapman fauna is probably 

somewhat older than the Grande Greve faun~t and certainly older than that of the York River 

(Gaspe sandstone) beds. It is also older than the faunas of the Moose River sandstone of Maine 

and the Nictaux beds· of New Brunswick. 

FAUNA OF THE MOOSE RIVER SANDSTONE. 

In this work several species from the Moose River sandstone have been mentioned and figured. It has not been the purpose to describe the fauna of this formation; the species selected 

were brought in for comparison, chiefly to show that stratigraphically the Chapman fauna lies 

below this eastern· representative of the Oriskanian fauna of New York. From the species 

cited it is evident that this Moose River sandstone is roughly equivalent to the Oriskany sa:ndstone of New York and the York River (Gaspe sandstone) of Gaspe Peninsula. As has been 

shown ~n the descriptions, most of the l\ioose River species cited do not occur in the Chapman 

fauna. With regard to the species of the Chapman fauna that are closely related to Moose 

River species the evidence is clear that the Chapman forms are earlier representatives of the 

·evolutional lines to which they belong than the Moose River forms. In conclusion, attention 

is directed to the correlations of individual species to be found in the body of the paper. 

SOURCE OF TI-lE SPECIES OF THE CHAPMAN FAUNA. 

While the species and genera have been under investigation, the question of their source has 

'been constantly in 1nind. The evidence is clear that compared- with corresponding faunas to 

the west the Chapman fauna shows greater affinities with transatlantic faunas; but the number 

·Of species identical with European forms is too few to lead to the supposition that the Chapman 

fauna had a different source from the corresponding New York faunas. It is more probable that 

the slight differences between it and the N ~w York Helderbergian may be accounted for by 

local conditions and slight differences in age, rather than by a different source. 

The details of comparison fron1.which these conclusions are drawn are brought out in the 

discussions of the genera and species in the body of the work, in which are recorded an abundance 

·Of references to closely allied species in every part of the world. These references furnish a 

contribution to the solution of the problem of sources, the study of which must be carried much 

further before generalizations of permanent value can be made. 

PLATES. 

301 

PLATE I. 

[All the figures on this plate are approximately of natural size.) 

Figures 1, 4, 5, 8, 0, 12, 16, 18, 19, 20, Spirifer r.yclopterus Hall (p. 88). (See also Pl. II, figs. 3, 5, 6, 7, 8, 10, 13, 14, 20, and Pl. IV, figs. 1, 10.) 

Figure 2, Spirifer montrealensis Williams (p. 113). (See also Pl. II, figs. 2, 18.) 

Figures 3, 10, 23, 25, 26, Spirifer murchi.~oni Castelnau (p. -). (See also Pl. II, fig. 9, and Pl. IV, figs. 8 (?), 9 (?).) 

Figures 6, 7, Spirifer concinnus Hall (p. 89). (See also Pl. II, figs. 1, 4, 11, 12; Pl. III, fig. 8; Pl. IV, figs. 5, 6; Pl. V, figs. 16, 17.) 

Flguros 11, 13, 14, 15, 17, 21, 22, 24, Spiri/er sparsus Clarke (p. 105). (See also Pl. II, fig. 17; Pl. IV, fi~. 2.) 

l. Spirifer cyclopterus Hall. Internal mold of a very large brachial valve, the largest seen. There are eight or nine 

ribs on each side. Chapman sandstone, west side of Edmunds Hill, Chapman Township, Aroostook County, 

Maine. 

2. Spirifer montrealmsis Williams (="Spirifer cf. S. granulosus Conrad" Schuchert). A large brachial valve in partial 

cast, showing between 16 and 22 narrow ribs on each side of the rounded fold. There are faint indications in 

the original of a slight groove in the upper part of the fold, 1Ltt in the retouching the fold has been made to 

appear smooth. Breccias of St. Helens Island, Montreal, Canada. 

3. Spirifer rnurchisoni Castelnau. An average brachial valve in internal mold, showing a rather low rounded fold and 

six ribs on each side. Moose River sandstone, Detroit, Somerset County, Maine. 

4. Spirifer C1JCZopterusllall. A brachial valve of average size in internal mold. There are only five or six ribs on each 

side; the outline is less transverse and more nearly square than in the specimen shown in figure 1. Chapman 

sandstone, west side of Edmunds Hill, Chapman Township, Aroostook County, Maine. 

5. Spirifcr cyclopterus Hall. Another brachial valve in internal mold, showing the rounded cardinal extremity on the 

right. '!'here are on this side only seven ribs in the origi.nal, possibly eight. In retouching, the specimen has 

been made to appear to have nine ribs on the side. Chapman sandstone, same locality as figure 4. 

6. Spirifcr concinnus Hall. Internal mold of a gibbous brachial valve with nine or ten ribs on each side and of average 

size and proportions but having the fold simple .. Chapman sandstone, Presque Isle Stream, Chapman Township, 

Aroostook County, Maine. 

7. Spir·ifer concinnus Hall. A brachial'valve in internal mold. This shows a deep median groove in the median fold, 

almost dividing the fold into two ribs. This character is more or less developed in most Maine specimens and 

shows a similarity to S. excavat'l.ts Kayser. Chapman sandstone, same locality as figure 6. 

8. Spirijer cyclopterus Hall. A small pedicle valve in internal mold; six ribs on each side. This is the smallest 

specimen of the species in the collection. Chapman sandstone, same locality as figure 4. 

9. Spirijer cyclopterus Hall. A small brachial valve in internal mold; seven ribs on each side. Chapman sandstone, 

same locality as figme 4. 

10. Spirifer murchisoni Castelnau. A brachial valve of average size in partial cast; six ribs on each side. Moose River 

sandstone, Detroit, Somerset County, Maine. 

11. Spirifer sparsus Clarke. A brachial valve in internal mold with three strong undulations or folds OIJ. each side. 

This is not the normal aspect of the species but shows a close similarity to Delthyris raricosta. Chapman sandstone, 2 miles west of Presque Isle Stream, Chapman Township, Aroostook County, Maine. 

12. Spirifer cycloptents Hall. A brachial valve of rather large size; internal mold; eight ribs on each side. Chapman 

sandstone, same locality as figure 4. 

13. Spir·ifer sparsus Clarke. A pedicle valve in internal mold; four ribs on each side. The musculature is impressed 

a little more strongly than usual in the species, though not so strongly as inS. murchisoni ( cf. figs. 25, 26). Chapman sandstone, Presque Isle Stream, Chapman Township, Aroostook County, Maine. 

14. Spir·ifer sparsus Clarke. A rather large complete brachial valve in internal mold, showing the ·broadly rounded 

hinge extremities, the high sub carinate median fold extended in front, and with four or five ribs on each side. 

Chapman sandstone, Edmunds Hill, Chapman Township, Aroostook County, Maine. 

15. Spirifer sparsus Clarke. A rather small brachial valve in partial cast, showing strongly elevated, rounded to subangular ribs, four on each side of the fold. Chapman sandstone, same locality as figure 14. 

16. Spitijer cyclopterus Hall. A large pedicle valve in internal mold, showing the deep sinus with eight ri.bs on each 

side; the musculature is impressed strongly for this species, but is relatively weak compared with that inS. 

murchisoni (cf. figs. 25, 26). Chapman sandstone, same locality as figure 4. 

17. Spir·ifer spars'l.ts Clarke. A brachial valve somewhat similar in appearance to that shown in figure 11. Chapman 

sandstone, same locality as figure 4. 

18. Spirijer cyclopterus Hall. A pedicle valve in internal mold, with a strongly impressed mwculature; only five ribs 

on each side the median sinus. Chapman sandstone, same locality as figme 4. 

303 
304 FAUNA·OF THE CHAPMAN SANDSTONE OF MAINE. 

19. Spirifer cyclopterus Hall. Another pedicle valve; five or six ribs on each side. Chapman sandstone, same locality 

as figure 4. 

20. Spirifer cyclopterus Hall. Another pedicle valve; six· or seven rib~ on each side. Chapman sandstone, same 

locality as figure 4. 1 

21. Spirifer sparsus Clarke. A rather large internal mold of a pedicle valve, showing a common aspect of the species 

with regard to the number of plications, their appearance, the outline, etc. Chapman sandstone, Presque Isle 

Stream, Chapman Township, Aroostook County, Maine. 

22. Spirifer sparsus Clarke. Internal mold of a pedicle valve with three or four strong undulations or ribs, somewhat 

resembling S. rnacropleurus. This is not the usual aspect of the Maine species but represents the same form as 

figure 11. Chapman sandstone, same locality as figure 11. 

23. Spirifermurchisoni Castelnau. A pedicle valve, the right side below the musculature' in external cast, the remainder 

in internal mold; five or six rounded ribs on each side. Note the high and.arched cardinal area and the normally 

very pronounced musculature of the species. Moose River sandstone, Detroit, Somerset County, Maine. 

24. Spirifer sparsus Clarke. A pedicle valve of normal aspect with cardinal area of moderate height and arched. Chapman sandstone, Edmunds Hill, Chapman Township, Aroostook County, Maine. 

25, 26. Spirifer murchisoni Castelnau: Two pedicle valves, a little different in outline, showing the typical muscula:-

ture of the species and the moderately high arched cardinal area. Moose· River sandstone, Detroit, Somerset 

County, M.aine .. 
U. S. GEOLOGICAL SURVEY PROFESSIONAL PAPER 89 PLATE I 

3 

2 1 

4 5 

6 7 

8 

9 10 11 

12 

15 

13 14 16 

17 18 19 20 

22 23 

21 

24 25 26 
U. S. GEOLOGICAL SURVEY PROFESSIONAL PAPER 89 PLATE II 

3 

2 

4 5 

6 

7 

10 

9 

8 

11 

12 

13 

14 

15 17 

16 

19 

18 

20 

21 
PLATE II. 

[All the figures on this plate are of approximately natural size.] 

Figures 1, 4, 11, 12, Spirifcr concinnus Hall (p. 80). (See also Pi. I, figs. 6, 7; Pi. III, fig. 8; Pi. IV, figs. 5, 6; Pl. V, figs. 16, 17.) 

Figures 2, 18, Spirifer montrealensis Wllllams (p. 113). (See also Pl. I, fig. 2.) 

Figures 3, 5, 0, 7, 8, 10, 13, 14, 20, Spirifcr cycloptcrus Hall (p. SS). (See also Pi. I, figs. 1; 4, 5, 8, 9, 12, 16, 18, 19, 20; Pl. IV, figs. 1, 10.) 

J?lguro 9, Spirifcr murr.hisoni Castelnau (p. 95). (See also Pl. I, figs. 3, 10, 23, 25, 26; Pl. IV, figs. 8 (?), 9 (?).) 

:Figures 15, Hi, 19, 21, Spirifer arcnosus Conrad (p. 84). (See also Pl. III, fig. 1; Pl. V, fig. 18.) 

l?fguro 17, Spirifer spar8U8 Clarke (p. 105): (See also Pi. I, figs. 11, 13, 14, 15, 17, 21, 22, 24; Pi. IV, fig. 2.) 

1. S1)injer concinnus Hall. A large pedicle valve in partial cast, with nine to ten or eleven ribs on each side of the 

angular sinus. Chapman sandstone, Presq'ue Isle Stream, Chapman Township, Aroostook County, Maine. 

2. Spirijer montrealensis Williams. Ventral view of a large pedicle valve showing the sinus without any riblet in 

the middle and its bounds not sharply defined. Breccias of St. Helens Island, Montreal, Canada. 

3. Spirijer cyclopterus Hall. External cast of pedicle valve; seven or eight ribs on each side. Chapman sandstone, 

west side of Edmunds Hill, Chapman Township, Aroostook County, Maine. 

4. Spirijer concinnu~ Hall. A pedicle valve in external cast; eleven ribs are discernible on each side; there may have 

been twelve to thirteen or fourteen. Breccias of St. Helens Island, Montreal, Canada. 

5. Spirijer cyclopterus Hall. A small pedicle valve showing very low beak. Compare with the umbo in figures 

3 and 8. Chapman sandstone, same locality as figure 3. . 

6. Spirijer cyclopterus Hall. A small pedicle valve in partial cast, with only four or five ribs on each side. Chapman sandstone, same locality as figure 3. · 

7. Spirijer cyclopterus Hall. External cast of pedicle valve, internal mold in front; only five or six ribs on mold, seven 

or eight ribs on external surface. Chapman sandstone, same locality as figure 3. 

8. S])ir·ijer cyclopterus Hall. Very large pedicle valve in external cast; seven or eight ribs on each side. This is the 

largest specimen of the species in the collection. Chapman sandstone, same locality as figure 3. 

9. Spirijer murchisoni Castelnau. Exterior cast of pedicle valve. Note the weak ribs bounding the sinus and the 

characteristic transverse extension of the species. Moose River sandstone, Detroit, Somerset County, Maine. 

10. Spirijer cyclopterus Hall. A gibbous pedicle valve with seven or eight ribs on each side and acute lateral extremities. Chapman sandstone, sam~ locality as figure 3. 

11. Spirijer concinnus Hall. Cardinal view of a small internal mold, showing the pedicle valve not much more convex than the brachial and with an arched cardinal area. of moderate height. Chapman sandstone, same locality 

as figure 1. · 

12. Spirijer concinnus Hall Cardinal view of another pedicle valve to show the area. Chapman sandstone, same locality as figure 1. · .. 

13, 14. Spir·ijer cyclopterus Hall. Two small pedicle valves, exterior cast, with six or seven ribs on each side. 

Chapman sandstone, same locality as figure 3. 

15. Spirijer arenosus Conrad. Exterior of a small pedicle valve with sixteen or more ribs on each side. Moose River 

sandstone, Detroit, Somerset County, Maine. 

16. Spirijer arenosus Conrad. A mature pedicle valve in partial cast, showing traces of the large S. murchisoni type 

of musculature; about eighteen simple ribs on each side. Moose River sandstone,. same locality as figure 15. 

17. Spirifer sparsus Clarke. A pedicle valve (exterior cast) showing the characteristic three strong ribs on each side 

of the narrow sinus and two faint ones beyond. In retouching the photograph the fourth rib ·on the right side 

has been made to appear a trifle too strong. Chapman sandstone, 2 miles west of Presque Isle Stream, Chapman Township, Aroostook County, Maine. 

18. Spirifer montrealensis Williams. A partial cast of a mature pedicle valve, showing the sinus angular in the bottom 

with undefined margins and without a median riblet. Breccias of St. Helens Island, Montreal, banada. 

19. Spirijer arenosus Conrad. A small pedicle valve, exterior cast, similar to that shown in figure 15. Moose River 

sandstone, same locality as figure· 15. 

20. Spirijer cyclopterus Hall. Exterior cast of a small pedicle valve only 8 millimeters long, with four or five ribs 

on each side. Chapman sandstone, same locality as figure 3. 

21. S])irifcr arenosus Conrad. An exterior cast in wax. Moose River sandstone, same locality as figure. l5. 

50245°-No. 89-16--20 305 
PLATE III. 

[All the figures on this plate are enlarged 2 diameters except fig. 10.) 

Figure 1, Spirifer arenosus Conrad (p. 84). (See also PI. II, figs. 15, 16, 19, 21; PI. V, fig. 18.) 

Figures 2, 3, 4, 7, 12, Spirifer arenosus var. simplex var. nov. (p. 86). 

Figure 5, Spirifer concinnus Hall (p. 80). (See also PI. I, figs. 6, 7; PI. II, figs. 1, 4, 11, 12; PI. IV, figs. 5, 6; PI. V, figs. 16, 17.) 

Figures 6, 9, 11, Chonetes (Eodevonaria) arcuatus Hall (p. 53). 

Figure 8, Chonetes vicinus var. dejlectus Hall (p. 49). 

Figure 10, Schuchertella woolworthana Hall (p. 34). 

l. Spirijer arenosus Conrad. Exterior of a silicified pedicle valve, showing a mature type of plicated sinus in the 

typical form of the species, the median rib bifurcating early in its growth and halfway down developing a 

secondary rib by implantation between the two branches of the original rib. X 2. Oriskany sandstone, 

Keyser, Mineral County, W.Va. · 

2. Spirijer arenosus var. simplex var. nov. Internal moid of a pedicle valve in a coarse quartzitic sandstone. X 2. 

Oriskany sandstone, Keyser, Mineral County, W. Va. 

3. Spirijer arenosus var. simplex var. nov. Exterior of a silicified pedicle valve, showing the typical feature of the 

variety-a thick, undivided rib in the middle of the sinus and a single weaker rib on each side, formed by 

bifurcation of the marginal ribs of the sinus. X 2. Oriskany sandstone, same locality as figure l. 

4. Spirijer arenosus var. simplex var. nov. Internal mold of a pedicle valve,·showing the characteristic embryonic 

type of plicated sinus of this variety; this specimen is l~rger than that shown in figure 1, which bears the norma] 

or mature plicated sinus of the typic:1l form of the species. X 2. Oriskany sandstone, same locality as figure 2. 

5. Spirijer concinnus Hall. Partial cast of pedicle valve, showing the large form of the species, with 13 or 14 ribs on 

each side, the sinus shallow, and the faintly appearing rib let on each side. X 2. Oriskany sandstone, Covington, Alleghany County, Va. 

6. Chonetes (Eodevonaria) arcuatus Hall. Mold of interior of pedicle valve, showing the gibbous body and flattened 

ears, the septum and lineation' of surface .. X 2. Moose River sandstone, Little Brassua Lake, Somerset County, 

Maine. 

7. Spirijer arenosus var. simplex var. nov. Fragment of internal mold of this variety, the usual form in the collections 

from this locality. X 2. Oriskany sandstone, same locality as figure 2. 

8. Chonetes vicinus var. dejlectus Hall. A small imperfect pedicle valve, showing the lineation of the surface; the 

. hinge margin imperfect. X 2. Moose River sandstone, same locality as figure 6. 

9. Chonetes (Eodevonaria) arcuatus Hall. Mold o'f interior of pedicle valve, showing on the left side the crenulate 

hin.ge area. X 2. Moose River sandstone, same locality as figure 6. 

10. Schuchertella woolworthana Hall. An internal mold of a brachial valve, showing the outlines and portions of the 

shell perfectly. Natural size. Moose River sandstone, Big Brassua Lake, Somerset County, Maine. 

11. Chonetes (Eodevonaria) arcuatus Hall. A somewhat larger pedicle valve than those shown in figures 6 and 9, illustrating strongly gibbous body part of shell, flattened ears and septum; also on the right the crenulate hinge area. 

X 2. Moose River sandstone, same locality as figure 6. 

12. Spirijer arenosus var. osimplex var. nov. Fragment of internal mold of pedicle valve showing impressions of the 

plications on the umbonal area, musculature weak. X 2. Oriskany sandstone, same locality as figure 2. 

306 
PROFESSIONAL PAPER 89 PLATE Ill 

U.S. GEOLOGICAL SURVEY 

3 

5 

9 

12 11 
U.S. GEOLOGICAL SURVEY PROFESSIONAL PAPER 89 PLATE IV 

3 

2 

l 

4 

6 

5 

7 

10 

8 
PLATE IV. 

[All the figures on this plate are enlarged 2 diameters.) 

FJguros 1, 10, Spirifer cyclopterus Hall (p. 88). See also PI. I, figs. 1, 4, 5, 8, 9, 12, 16, 18, 19, 20; PI. II, figs. 3, 5, 6, 7, 8, 10, 13, 14, 20.) 

I<'Jguro 2, Spirifer sparsus ClarkQ (p. 105). See also PI. I, figs. 1i, 13, 14, 15, 17, 21, 22, 24; PI. II, fig. 17.) 

FJgures 3, 4, Spirifor cr. S. duodenarius Hall (p. 104). 

J<Jgures 5, 6, Spirifcr concinnus Ho.ll (p. 80). (See also PI. I, figs. 6, 7; PI. II, figs. 1, 4, 11, 12; PI. III, fig. 8; PI. V, figs. 16, 17.) 

:FJguro 7, Spirifcr gaspcnsis Billings (p. 107). 

FJgures 8, 9, Antispirifer harroldi var. transversa gen., sp., et var. nov. (p. 117). 

1. Spirijer cyclopterus Hall. Internal mold of a pedicle valve. X 2. Chapman sandstone, Edmunds Hill, Chapman 

Township, Aroostook County, Maine. 

2. Spirijer spars1ts Clarke. Brachial valve; internal mold, left side. . X 2. Chapman sandstone, same locality as 

figur~ 1. · 

3. Spirijm· duodenari-us Hall. Internal. mold of a fragment of a brachial valve, showing a slight cardinal area, the 

muscular and septal scars, etc. X 2. :Moose River sandstone, Big Brassua Lake, Somerset County, Maine. 

4. Spitijer duodenari1ts Hall. Ventral view of a rather small individual in partial cast, showing the transverse outline, 

five or six rounded ribs, and a relatively narrow rounded sinus. X 2. Moose River sandstone, same locality as 

figure 3. 

5. Spirijer concinnus Hall. A rather large brachial valve with 11 or 12 ribs on each side. The exterior of the fold 

must have been strongly bifid, as in S. excavat1ts Kayser. X 2. Chapman sandstone, west of Presque Isle 

Stream, Chapman Township, Aroostook County, Maine. 

6. Spirijer concinnus H:tll. A small specimen with small rounded ca:rdinal extremities, showing sulcus along the 

center of the medial fold of the brachial valve. X 2. Chapman sandstone, same locality as figure 5. 

7. Spirijer gaspensis Billings. Internal mold of a medium-sized brachial valve, showing the characteristic transverse• 

outline and high medial fold, with 12 or 13 ribs on the side. X 2. Moose River sandstone, Little Brassua Lake, 

Somerset County, Maine. 

8. Antispirijer harroldi var. transversa gen., sp. et var. nov .. A large brachial Yah·e in internal mold, showing the 

close resemblance of this valve to the corresponding valve of Spirijer murchisoni. (Compare Pl. I, fig. 3.) Common 

in a mass of Leptocw.Jiajlabellites. Moose River sandstone, Parlin Ponrl, Somerset County, Maine. 

9. Antispirijer lwrroldi var. transversa gen., sp. et var. nov. Pedicle valve, internal mold, showing the characteristic. 

flat cardinal area of the species. X 2. Moose Rh;er sandstone, Parlin Pond, Somerset County, Maine. 

10. Spirifer cyclopterus Hall. Pedicle valve with unusually strong musculature. X 2. Chapman sandstone, west of 

Presque Isle Stream, Chapman Township, Aroostook County, Maine.' 

307 
PLATE V. 

[All the figures on this plate are of approximately natural size.] 

Figures 1-13, A ntispirifer harroldi gen. et sp. nov. (p. 116). 

Figure 14, Cyrtina rostrata Hall(p. 76). 

Figure 15, Cyrtina heteroclita Defrance var. (p. 79). 

Figures 16, 17, Spirifer concinnus Hall (p. 80) .. (See als~ PI. I, figs. 6, 7; PI. II, figs. 1, 4, 11, 12; Pl. III, fig. 8; Pl. IV, ftgs. 5, 6.) 

Figure 18, Spirifer arenosus Conrad (p. 84). (See also Pl. II, figs. 15, 16, 19, 21; Pl. III, fig. 1.) 

Figures 19-30, Leptocrelia jl.abellites Conrad (p. 120). · 

Figures 31-33, Nucleospira ventricosa Hall(p. 118). 

1. Antispirifer harroldi gen. et sp. nov. Wax impression of the external mold of a pedicle valve, showing the outline 

and proportions, very depressed convexity, five or six rounded ribs on each.side, the narrow, abrupt median 

sinus, and the lamellose concentric ornamentation. Moose River sandstone, Parlin Pond, Somerset County, 

Maine. 

2. Antispirifer harroldi gen. et sp. nov. External mold of pedicle valve, showing the flat surface and lamellose concentric ornamentation. Fine radial lines, especially well developed near the edges of the lamellre, are present 

on the original but do not appear in the figure. (See fig. 8.) Moose River sandstone, Detroit, Somerset 

County, Maine. 

3. Antispirijer harroldi gen. et sp. nov. Wax impression of external mold of exterior of pedicle valve, showing 

six or seven rounded ribs and narrow abrupt sinus. (See fig. 9.) Moose River sandstone, same locality as· 

figure 2. · 

4. Antispirijer harroldi gEm. et sp. nov. The convex or brachial valve in partial castwith six roundedribsoneach 

side of the low rounded fold. Moose River sandstone, same locality as figure 2. 

5, 6, 7 . . Antispirifer harroldi gen. et sp. nov. Internal molds of pedicle valves, showing the characteristic very wide, 

strongly impressed musculature and the flat cardinal area of medium height; the latter character well indicated 

in figures 6 and 7. Moose River sandstone, same locality as figure 2. . 

8. Antispirijer harroldi gen. et sp. nov. Wax impression of the original specimen of figure 2. 

9. Antispirifer harroldi gen. et sp. nov. External mold 0f the original .specimen from which was taken the wax 

impression shown in figure 3. Moose River sandstone, same locality as figure 2. ·-

10, 11, 12. Antispirifer harroldi gen. et sp. nov. Three flat pedicle valves in partial cast, illustrating the usual appearance in the hard unweathered rock. Moo6e River sandstone, same locality as figure 2. 

13. Antispirifer harroldi gen. et sp. nov. :·Fragments of two brachial valves in internal mold, so superimposed that the 

figure seems to represent only one fractured valve. Moose River sandstone, same locality as figure 2. 

14. Cyrtina rostrata Hall. Cardinal view of an internal mold of a pedicle valve, showing the high, nonarching cardinal 

area and narrow covered delthyrium. Chapman sandstone, west.side of Edmunds Hill, Chapman Township, 

Aroostook Co,unty, Maine. '. ·' 

. 15. Cyrtina heteroclita Defrance var. alpha. A worn internal mold of pedicle valve, showing faint indications of ribs. 

Chapman sandstone, same locality as figure 14. 1 

16, 17. ?Spirifer concinnus Hall. Two decorticated brachial valves referred to this species. Chapman sandstone, 

Edmunds Hill, Chapman Township, Aroostook County, Maine. 

18. Spirifer arenosus Conrad. · Internal mold of a small pedicle valve. Moose River sandstone, Detroit, Somerset 

County, Maine. 

19. Leptocceliajlabellites Conrad. A brachial valve in partial cast,. showing the two median ribs slightly elevated into 

a fold, with three ribs and possibly a fourth on each side. Moose River sandstone: Detroit, Somerset County, 

Maine. . . • 

20. Leptoccelia jlabellites Conrad. Brachial valve of another individual, internal mold; shows the cavity in the 

umbo, impressed by tli~ massive cardinal process, hinge plate, etc. There seem to be only eight ribs, as in the 

specimen shown in figure 19. Moose River sandstone, same locality as figure 19. 

21-23. Leptoccelia jlabellites Conrad. Three pedicle valves in internal mold. Note the median septum, distinct 

adductor muscular scars, and faintly exp~essed diductors. The median sinus is well developed in the specimen 

shown in figure 22. Figure 23 shows a median rib, which is not developed in the valve shown in figure 21. 

Note the cavities left by the large teeth shown in figures 21 and 22. Moose River sandstone, same locality as 

figure 19. 

24. Leptoccelia jlabellites Conrad. Brachial valve iQ. internal mold, showing the deep impressions of the cmral bases 

and the massive cardinal process. Moose River sandstone, same locality as figure 19. . 

25: Leptoccelia jlabellites Conrad. Pedicle valve in partial cast, showing a well-developed sinus ~ithout median rib, 

similar to that shown in figure 22. There at:e four or five ribs on each side. Moose River sandstone, same 

locality as figure 19. 

308 
U. S. GEOLOGICAL SURVEY PROFESSIONAL PAPER 89 PLATE V 

1 2 3 4 

5 

8 9 

10 6 

7 14 

15 

13 

12 16 

11 

17 

19 20 21 

18 

22 

24 25 

26 23 27 

28 29 30 31 32 33 
PLATE V. 309 

26-27. Leptocreliajlabellites Conrad. Two brachial valves in external mold, each with 10 ribs. There is no indication 

o(a medinn fold. Moose River snndstone, same locality as figure 19. 

28. Leptocreliajlabellites Conrad. A brachinl valve in pa.rtial cast, showing a duplicate median fold and three, possibly 

four, "ribs on each side, as in figure 19, but showing a different outline. Moose River sandstone, same locality 

as figure 19. 

29. Leptocrelia jlabellites Conrad. Another brachial valve in internal mold, showing the impressions of the cardinal 

process, cruml bases, and median septum. Moose. River sandstone, same locality as figure 19. 

30. Leptocreliajlabellites Conrad. Two small brachial valves, one in external mold and one in internal mold. Moose 

River snndstone, same locality as figure 19. 

31. Nucleospira ventricosa Hall. A small pedicle valve in internal mold, illustrating the strong convexity of the 

species. Chapman sandstone, 2! miles west of Presque Isle Stream, Chapman Township, Aroostook County, 

Maine. 

32. Nucleosp·ira 11entricosa Hall. Pedicle valve of another strongly convex individual in internal mold, showing the 

impressions of the teeth, the muscular scars, and the median septum. Chapman sandstone, Edmunds Hill, 

Chapman Township, Aroostook County, Maine. 

33. Nucleospi-ra ventricosa Hall. A pedicle (?) valve in partial cast. Chapman sandstone, snme locality as figure 32. 
PLATE VI. 

[All the figures on this plate are or approximately natural size.] 

Figures 1, 2, 3, 6, 9, Dalmanella elevata sp.nov. (p. 62). (See also Pl. VII, figs. 12, 19, 23; Pl. VIII, figs. 1 i -22.) 

Figures 4, 5, 7, 10, 14,21 ,22, 25, 26, Stenosci8maformosa Hall (p. 64). 

Figures 8, 18, Eatonia 8ingularis Va~uxem (p. 69). 

Figure ll,Ren88elaeria mainensi8 Williams (p. 72). (See also Pl. XI, figs. 1-15.) 

Figure 12, Rhynchonella cf. R. mainensi8 Billings (p. 2i). 

Figure 13, Crania sp. indet. (p. 24). 

Figure 15, Megalanteris? sp. (p. 71). (See also Pl. VII, fig. 15.) 

Figures 16, 19, 20, Jl:feristella bella Hall (p. 124). 

Figure 17, Dalmrinella planiconvexa Hall (p. 57). (See also Pl. VII, figs. 11, 13, 14, 16, 17, 18, 20, 21, 24, 24-30.) 

Figure 23, Eunella ellsi (Clarke) (p. 76). 

Figure 24, uf. Pentagonia gen. et sp. indet. (p. 125). 

Figure 27, Lingula minuscula sp. nov. (p. 20) . 

.Figures 28-33, Orbiculoidea (Roemerella) discus Hall (p. 21). 

1. Dalmanella elevata sp. nov. Brachial valve, showing the cardinal area. Chapman sandstone, Edmunds Hill, 

Chapman Township, Aroostook County, Maine. 

2. Dalmanella elevata sp. nov. Partial interj..or cast of brachial valve. Chapman sandstone, same locality as figure 1. 

.3. Dalmanella elevata sp. nov. Partial exterior cast of brachial valve. Chapman sandstone, same locality as figure 1. 

-4. Stenoscisma.formosa Hall. Pedicle valve in partial exterior cast, showing three or four ribs in the sinus and six 

on each side. Chapman sandstone, west side of Edmunds Hill, Chapman Township, Aroostook County, Maine . 

. 5. Stenoscismaformosa Hall. An old pedicle valve in internal mold, showing strong diductor and adductor, dental 

lamellre obsolescent; three ribs in sinus and five or six on each side. Chapman sandstone, same locality as 

figure 4. 

6. Dalmanella elevata sp. nov. Brachial valve in external mold; the only specimen showing the characteristic coarse 

striations. Chapman sandstone, same locality as figure 1. 

7. Stenoscismajormosa Hall. Brachial valv~in partial external cast; four ribs on the fold, five on each side. Chapman sandstone, same locality as figure 4. 

8. Eatonia singularis Vanuxem. Ventral view of an individual in external cast and internal mold. Chapman sandstone, west side of Edmunds Hill, Chapman Township, Aroostook County, Maine. 

9. Dalmanella elevata sp. nov. Brachial valve in internal cast, showing muscular scars simi~r to those in figure 1. 

Note the conspicuous sinus in all the brachial valves. Chapman sandstone, same locality as figure 1. 

10. Stenoscisma formosa Hall. Pedicle valve in internal mold, showing strong muscular scars, four ribs in the sinus 

and six or seven on each side, with bifurcating rib bordering the sinus on the left side. Chapman sandstone, 

same locality as figure 4. 

11. Rensselaeria mainensis Williams. A very small pedicle valve in exterior cast. (See Pl. XI, figs. l-15.) Chapman 

sandstone, 2~ miles west of Presque Isle Stream, Chapman Township, Aroostook County, Maine. 

12. Rhynchonella (cf. R. mainensis Billings). Brachial valve in internal mold, showing the crural bases and absence 

of a median septum. Chapman sandstone, same locality ae figure l. 

13. Crania sp. Brachial valve in interrtal mold. Chapman sandstone, same locality as figure 4. 

14. Stenoscisrnajormosa Hall. A pedicle valve in internal mold, showing the incisions made by the dentallamellre, 

the presence of which removes this spt:cies from the genus Rhynchotrema. Chapman sandstone, same locality 

as figure 4. 

15. Megalanteris? sp. Fragment o£ a pedicle valve in internal mold, showing the incisions of the short subparallel 

dental lamellre, the absence of musculat impressione, and the smooth surface appearance. Chapman sandstone, same locality as figure 4. 

16. Meristella cf. 1lf. bella Hall. Large brachial valve in internal mold, showing small size of the species and the 

obscure sinus. Chapman sandstone, same locality as figure 4. 

17. Dalrnanella planicom;exa Hall. Pedicle valve in internal mold, showing the rounded outline, short hinge: and 

natrow elongate musculature. Chapman sandstone, same locality a.s figure 4. 

18. Eatonia singularis Vanuxem. Dorsal view of same individual a& figure 8, in internal mold, showing the fold 

extending af.J far as the beak. Chapman sandstone, same locality as figure 4. 

19. Jferistella cf. Jf. bella Hall. Pedicle valve in partial internal inold. Chapman sandstone, same locality as figure 4. 

20 . . Meristella cf . .M. bella Hall. Pedicle valve in internal mold, showing the depression formed by the hinge plate and 

the musculature in front of iL Chapman sandstone, same locality as figure 4. 

21. Stenoscisma formosOJ Hall. Pedicle valve in exterior cast; four ribs in the sinus, six on each side. Chapman 

san.dstone, same locality as figure 4. 

310 
U. S. GEOLOGICAL SURVEY PROFESSIONAL PAPER 89 PLATE VI 

1 2 

3 4 5 

6 7 10 

8 9 

11 

12 15 

14 

13 

16 

21 

17 

19 

18 

23 22 

28 20 24 

~ 25 27 26 

30 

29 

31 32 33 
PLATE VI. 311 

22. Stenoscisrnajormosa Hall. A large padicle valve .in internal mold with three ribs in the Sinus and six or seven 

on each side. Chapman sandstone, same locality as figure 4. 

23. E·unella ellsi Clarke. A single internal mold of a pedicle valve: having the outline, convexity, size, and other 

features of this species. Chapman sa.ndstone, same locality as figure 4. · ·· . 

24. cf. Pentagonia sp. indet. Internal mold of a brachial valve with the curvature of this genus but without'a vlsibie 

median septum. Chapman sandstone, same locality as figure 1. 

25. Stenoscismajormosa Hall. Internal mold of ~t very small individual, dorsal view, showing the median septum, 

which is divided posteriorly. Chapman sandstone, same locality as figure 4. 

26. Stenoscismajormosa Hall. Ventral view of the individual illustrated .in figure 25, showing thevery well developed 

dentallamellre. In th.is specimen, which is a young individual, the fold and sinus are just begin~ng to develop 

on the front margin. Chapman sandstone, same locality as figure 4. 

27. Lingula minusculq. sp. nov. Ventral view of a complete individual, slightly fractured. Chapman sandston~, 2 

miles west of Presque Isle Stream, Chapman Township, Aroostook County, Maine. 

28. OrbiC'I.tloidea (Roenwrella) discus Hall. Exterior of an elongate ped.icle valve:with strong radial ornamentation 

obscure in the figure,'showing the large pedicle opening and posterior slit. Chapman sandstone, Edmunds Hill, 

Chapman Township, Aroostook County, Maine. · · 

29. Orbiculoidea (Roemerella) discus Hnll. Fragment of exterior of large brachial valve. Chapman sandstone, same 

locality as figure 27. 

30. Orb·iculoidea (Roemerella) disC'I.tS Hall. Fragment of exterior of a brachial (possibly a pedicle) valve, showing 

obscure, very fine radial markings. Chapman sandstone, Edmunds Hill, Chapman Township, Aroostook 

County, Maine. 

31. Orbiculoidea (Roemerella) disC'I.tS Hall. Interior view of a large concave pedicle valve, showing only concentric 

lineation. Chapman sandstone, Presque Isle Stream, Chapman Township, Aroostook County, Maine. 

32, 33. OrbiC'I.tloidea (Roem.erella) discus Hall. External molds of two large convex brachial valves, showing only 

concentric lineation. Chapman Aandstone, same locality as figure 31. 
. PLATE . VII. 

[All the figures on· this plate are· of approximately natural size.~ 

Figures 1, 2, 3, 4, 5, 7, 8, Hipparionyx unguiformis Conrad (:,. 41). 

Figures 6a, 6b, Schuchertella deformis (Hall) (p. 40). 

Figure 9, Dalmanclla circularis 'I (Sowerby) (p. 59). 

Figure 10, Dalmanella plaruxionvexa Hall, with Chonetes novascoticus Hall (p. 5?). 

Figures 11, 13, 14, 16, 17, 18, 20, 21, 22, 24-30, Dalmanella planiconvexa Hall (p. 71). (See also PI. VI, fig. 17.) 

Figure 15, Megalanteris? sp. (p. 71). (See also PI. VI, fig. 15.) 

Figur~ 12, 19, 23, Dalmanella elevata sp. nov. (p. 62). (See also Pl. VI, figs. 1, 2, 3, 6, 9; PI. VIII, figs. li-22.) 

1. Hipparionyx unguiformis Conrad. The fiat pedicle valve in external mold, showing the fine radial strire which 

increase by implantation and arch backward on the cardinal slopes. Chapman sandstone, Edmunds Hill, 

Chapman Township, Aroostook County, Maine. 

2. Hipparionyx unguiformis Conrad. The fiat or resupinate pedicle valve in internal mold, showing the ovarian area 

and strong musculature. Chapman sandstone, west side of Edmunds Hill, Chapman Township, Aroostook 

County, Maine. 

3. Hipparionyx unguiformis Conrad. Another fiat (resupinate) pedicle valve in external mold, showing a rather 

elongate form sim,ilar to that of the shell shown in figure 1 (due possibly to lateral compression).. . Chapman 

sandstone, Edmunds Hill, Chapman Township, Aroostook County, Maine. 

4. Hipparionyx ung·uiformis Conrad. A pedicle valve in external cast; the shell broken away at the beak, exposing 

part of the musculature. Illustrates the short, wide form of the species. Chapman sandstone, same locality as 

figure 2. 

5. Hipparionyx unguijormis Conrad. Fragment of pedicle valve in internal mold, showing the characteristic upward 

curve of the strire on the latero-posterior margin. (Compare fig. 2.) Chapman sandstoile, same locality as 

figure 3. 

6a. Schuchertella deformis Hall. Partial cast of a convex pedicle valve, with gibbous umbo, which has not yet become 

resupinate or irregular in growth. Chapman sandstone, same locality as figur·e 2. 

6b. Schuchertella dlformis Hall. Brachial valve in partial cast. This resembles a })rachial valve of Hipparionyx but 

the striation is different. Chapman sandstone, same locality as figure 2. 

7. Hipparionyx unguiformis Conrad. Another comparatively wide pedicle valve. Chapman sandstone, same locality 

as .figure 2. 

8. Hipparionyx unguiform·is Conrad. A pedicle valve in external mold, illustrating the elongate form of the spec~es 

of this locality. Chapman sandstone, same locality as figure 3. 

9. Dalmanella cf. D. circularis (Sowerby). A brachial valve in external mold, showing the fiat valve with indistinct 

sinus and having the strire bifurcating but nonfasciculate. Chapman sandstone, same locality as figure 2. 

10. Dalmanella planoconvexa Hall. A pedicle valve in internal mold, showing the outline of the species and the musculature; with Chonetes novascoticus Hall on the same block. Chapman sandstone, same locality as figure 2. 

11. Dalmanella planiconvexa Hall. Flat brachial valve with obscure sinus showing the fasciculate strire. Chapman 

sandstone, same locality as figure 2. 

12. Dalmanella elevata sp. nov. A pedicle valve of this species, showing traces of the very coarse ornamentation and 

illustrating the acuminate umbo and sharp cardinal extremities of the_ species. Chapman sandstone, same 

locality as fig~ue 3. 

13. Dalmanella p~anoconve:m Hall. A fiat brachial valve, external mold, with very obscure sinus and faSciculate 

st.rire. Chapman sandstone, same locality as figure 2. . 

14. Dalmanella planocon'vexa Hall. A small brachial valve in external mold, with strongiy fasciculate strire. Chapman sandstone, same locality as figure 2. 

15. Megalanteris? sp. A pedicle valve in intern~l mold, showing the smooth form and nearly horizontal posterior 

margin; there is no muscular impression. Chapman sandstone, same.locality as figure 2. 

16. Dalmanella planoconvexa Hall. A brachial valve in internal mold, showing the characteristic appearance of 

muscular scars and caJ;dinal process. Chapman sandstone, same locality as figure 3. 

17. Dalmanella planoconvexa Hall. A pediCle valve. · Chapman sandstone, same locality as figure 3. 

18; 20. Dalmanella planoconvexa Hall. Two pedicle valves in internal mold, showing the outline, the somewhat 

characteristic musculature, and the marginal fringe of stri.:e. Chapman sandstone, same locality as figure 2. 

i9. Dalmanella elevata sp. nov. Pedicle valve in partial external cast, showing the acuminate beak,. broad hinge, with 

sharp extremities, and the coarse strire. Chapman sandstone, same locality as figure 3. 

20. See figure 18. 

21, 22. Dalmanella planoconvexa Hall. Two brachial valves in partial internal cast. Chapman sandstone, same 

locality as figure 2. 

23. Dalmanella elevata sp. nov. Pedicle valve in internal mold, showing acuminate beak, sharp hinge extremities, and 

cordate musculature. Chapman sandstone, same locality as figure 3. . · . . 

24-28. Dalmanella planoconvexa Hall. Brachial valves in internal molds, showing the musculature and cardinal 

process. The latter is very plainly seen to be bilobed in the specimen of figure 28, but not in the others. (hapman sandstone, same locality as figure 2. 

29, 30. Dalmanella planocmwexa Hall. Internal molds of two pedicle valves, showing th!3 outline, the musculature, 

and the marginal fringe of strire. Chapman sandstone, same locality as figure 2. 

312 
U. S. GEOLOG ICAL SURVEY PROFESSIONAL PAPER 89 PLATE VII 

3 

2 

4 6a 6b 

7 10 8 

9 11 13 12 

14 

15 

17 

16 

18 19 20 

21 22 23 24 25 

26 27 28 29 30 
PROFESSIONAL PAPER 89 PLATE VIII 

U. S. GEOLOGICAL SURVEY 

8 

4 

2 

1 

5 6 

9 

7 

10 

3 

13 

14 16 

12 

17 18 19 

15 20 21 

24 
PLATE VIII. 

(All the figures on this plate are of approximately natural size.] 

Figures 1-7, 13, 14, 15, 16, Leptostrophia perplana Conrad (p. 27). (See also Pl. III, !'!g. 9; PI. XI, fig. 1i.) 

}?fgurcs 8-12, Leptama rhornboidalis Wilckeus (p. 32). · 

}?fgurcs 17-23, Dalrnanella clevata sp. nov. (p. 62). (See also Pl. VI, figs. 1, 2, 3, 6, 9; Pl. VII, figs. 12, 19, 23.) 

J?Jgurc 24, Chone.tes striatissimus sp. nov. (p. 44). (See also Pl. IX, figs. 1-10, 13, 14, 17,18; Pl. X, fig. 17.) 

}?Jgurc 25, Cl1onetes bastini Williams (p. 48). 

1, 2. Leptostrophia ptr]Jlana Conrad. Two pedicle valves in internal mold, showing the coarse appearance, the absence 

of wrinkles, and the broad obtuse musculature. These are typical forms of Billings's L. blain·villci. Moose 

RiYer· sandstone, Detroit, Somerset C~:mnty, Maine. 

3. Leptostropkia ]Jt.:rplana Conrad. lnter~ml mold of a pedicle valve, with musculature similar to that shown in figures 

1 and 2 (=tho form called L. blainvillei Billings). Chapman sandstone, west side of Edmunds Hill, Chapman 

Township, Aroostook County, Maine. 

4, 5. Lepto1:1trophia ]Jerplana Conrad. Two pedicle valves in internal mold, corresponding in the acute angle between 

the sides of tho musculature with tho form of the species called L. planulata Hall. Moose River sandstone, 

same locality a..'i figure 1. 

6. Lepto1:1lrophia pi.'1"plana Conrad. Internal mold of a pedicle valve with the acute and short musculature of the form 

of tho species called L. tu.llia. Billings. Chapman sandstone, Edmunds Hill, Chapmim Township, .Aroostook 

County, .Maine. 

7. Leptost·rophia ]Jt:rplana Conrad. Internal mold of a pedicle valve with the acute musculature of L. planulata Hall, 

Chapman sandstone, same locality as figure 3. 

8. Lept[ena· rlzomboidalis Wilckens. Internal mold of a pedicle valve, showing the geniculate downward curvature 

in front and the strongly impressed cordate musculature, but without the concentric corrugations. Chapman 

sandstone, Edmunds Hill, Chapman To,vnship, Aroostook County·, Maine. 

9. LQptmna rhombQidalis Wilckens. External mold of a brachial valve, showing the corrugations over the flat part of 

the surface, the abruptly geniculate front, and the radial strire. Chapman sandstone, west side of Edmunds 

Hill, Chapman Township, Aroostook County, Maine. 

10. Lept<cna rhomboidalis Wilckens. Partial cast and internal mold of a pedicle valve, showing the cardinal area, 

museulature, corrugations, etc. Chapman sandstone, same locality as figure 8. 

11. LeJ)l;.rma rhomboidalis \Vilckens. Pedicle valve in internal mold, showing the musculature. Chapman sandstone, same locality as figure 8. 

12. Le]Jt:.una rhomboidalis Wilckens. Another pedicle valve in internal mold, preserving the shell in places, accompanied by Chonetes novascoticus Hall. "Chapman sandstone, same locality as figure 9. 

13. Leptostrophia pcrplana Wilckens. External mold of pedicle valve of an elongate form with acute musculature 

comparable with M. tullia Billings and L. planula/a Hall. Chapman sandstone, same locality as figure 3. 

14. Leptosl.roplda ]Jerplana Conrad. External mold of pedicle valve of the form of the species called L. planulata 

Hall, showing fi11e striation, acute musculature, and faint, obscure concentric wrinkles. Chapman sandstone, 

same locality a.q figure 6. 

15. Lepf.ostrophia per7)lana Conrad. External mold of pedicle valve of the form of the species called L. t·ullia Billings, 

showing the rather elongated outline and indications of the acute musculature; there are no appreciable wrinkles. 

Chapman sandstone, same locality as figure 3. 

16. Leptostrophia ]Jerplana Conrad. "Sculpture cast" of a pedicle valve of the L. blain·villei form of' the species. 

Chapman sandstone, same locality as figure 1. . 

17, 18. Dalmanella ele·vata sp. nov. Lateral and cardinal views of specimen figure 23 (the type of• the species), showing the profile, musculature, high and broad cardinal area, and narrow, very acute delthyrium. Chapman 

sanclstone, Edmunds Hill, C1Iapman Township, Aroostook County, Maine. 

19. Dalmanella elevatu sp. nov. Lateral view of specimen shown in Plate VII, figure 23. Chapman sandstone, same 

locality us figure 17. 

20-22. Dalmanella elevata sp. nov. Three pedicle valves in internal mold, showing the characteristic musculature 

a.11d .high,. broad cardinal area. Figure 21 shows indications of the coarse strim, and figure 22 represents a 

specimen with an insinuated front margin. Chapman sandstone, same locality as figure 17. 

23. Dabnanellu elevata sp. nov. Internal mold of pedicle valve, showing also the surface ornamentation, elevation of 

beak, and musculature. Same specimen as figure 18. Chapman sandstone, Edmunds Hill, Chapman Township, Aroostook County, Maine. 

Z4. Chonetes striatiss1"mus sp. nov. .A slab of sculpture casts or internal molds, showing the size and proportions and 

the flat surface, with extremely fine striation. (See Pl. IX, fig. 10.) Chapman sandstone, 2! miles west of 

Presque Isle Stream, Chapman Township, .Aroostook County, Maine. 

25. Chonetes bastini Williams. A slab containing specimens of the species introduced here for comparison with 

Chonetes striatissim·us and Chonetes no?Jascoticus Hall. The original of this slab was collected by Prof. Shaler 

and party and was labeled "Silurian, Dennys River, Cobscook Bay district, Maine." (See Shaler, N. S., Am. 

Jour. Sci., 3d ser., vol. 32, pp. 35-60, July, 1886.) 

313 
PLATE IX. 

[All the figures on this plate are enlarged 2 diameters.] 

Figures 1-10, 13, 14, 17, 18, Chonetes striatissimus sp. nov. (p. 44). (See also Pl. VIII, fig. 24;, Pl. X, fig. 17.) 

Figures 11, 12, 15, 16, 19, Chonetes novascoticus Hall (p. 45). 

Figures 20, 21, Chonetes novascotic?fs Hall var. canadensis Billings (p. 49). (See also Pl. X, figs. 30, 31; Pl. XI, fig. 16.) 

1. Chonetes striatissimus sp. nov. Pedicle valve in external mold, showing the very fine, flexuous strire and conspicuous midrib. X 2. Chapman sandstone, 2 miles. west of Presque Isle Stream, Chapman Township, Aroostook 

County, Maine. 

2. Chonetes striatissimus sp. nov. Type specimen of the species, a pedicle valve preserving the exterior of the shell, 

showing the depressed convexity, fine flexuous strire, midrib, and obtuse hinge extremities. X 2. Chapman 

sandstone, same locality as figure 1. 

3. Chonetes striatissim'l.ts sp. nov. Pedicle valve in partial cast, showing midrib and, on the right side of the hinge, a 

couple of cardinal spines. X 2. Chapman sandstone, same locality as figure 1. 

4. Chonetes striatissim1ts sp. nov. A partly exfoliated pedicle valve, preserving indications of the very fine strire 

and the midrib. Same specimen as Plate X, figure 17. X 2. Chapman sandstone, 2~ miles west of Presque 

Isle Stream, Chapman Township, Aroostook County, Maine. 

5, 6. Chonetes striatissimus sp. nov. Two pedicle valves, showing the strength of the midrib on the external surface. 

X 2. Chapman sandstone, same locality as figure 1. 

7. Chonetes strieitissimus sp~ nov. Pedicle valve in external mold. X 2. Chapman sandstone, same locality as 

figure 1. 

8. Chonetes striatissimus sp. nov. Interior cast of a pedicle valve, showing only faint indications of the midrib on the 

interior surface of the shell. X 2. Chapman sandstone, same locality as figure 1. 

9. Chonetes striatissimus sp. nov. Brachial valve in external mold, showing entire absence of midrib. X 2. Chapman 

sandstone, same locality as figure 1. 

10. Chonetes striatissimus sp. nov. Internal mold of a pedicle valve (one of those on the slab in Pl. VIII, fig. 24), 

show;i.ng the extreme indistinctness of the superficial midrib on the interior. X 2. Chapman sandstone, same 

locality as figure 4. 

11. Chonetes novascoticus Hall. A rather small pedicle valve in internal mold preserving the narrow cardinal area and 

some of the spines. Note also the coarser striation of this species. X ·2. Chapman sandstone, west side of 

Edmunds Hill, Chapman Township, Aroostook County, Maine. 

12. Chonetes novascoticus Hall. A small pedicle valve in internal mold, indicating the coarser striation of this species. 

Same specimen as Plate X, figure 1. X 2. Chapman sandstone, same locality as figure 1. 

13. Chonetes striatissimus sp. nov. Partly exfoliated pedicle valve, preserving the midrib. In retouching this photograph the strire have been made to appear too distant in places. Chapman sandstone, same locality as figure 1. 

14. Chonetes striatissimus sp. nov. Exterior of a small flat brachial valve; showing fine striation-and absence of midrib. 

X 2. Chapman sandstone, same locality as figure 1. 

· 15. Chonetes novascoticus Hall. Another small pedicle valve in internal mold. Same specimen as Plate X, figure 2. 

X 2. Chapman sandstone, same locality as figure 11. 

16. Chonetes novascoticus Hall .. A characteristic typical valve of this species. in external mold, showing the absence 

of midrib, the coarser strire, and some of the cardinal spines. X 2. Chapman sandstone, same locality as 

figure 11. · 

17. Chonetes striatissinvus sp. nov.· An imperfect fragment of a pedicle valve in internal mold. X 2. Chapman sandstone, same locality as figure 1. · 

18. C~wnetes striatissimus sp. nov. Exterior of the shell of the pedicle valve, showing the midrib and very fine flexuous 

strire. Chapman sand.stone, same locality as figure 1. 

19. Chonetes novascoticus Hall. Another characteristic pedicle valve in external mold, showing the spines, the coarser 

striation, the absence of midrib, etc. Chapman sandstone, same locality as figure 11. 

20. Chonetes novascotiws Hall var. canadensis Billings. A medium-sized or rather small pedicle valve in internal mold, 

indicating the large size of this form. The outline, depressed convexity, and striation are similar to those of 

C. novascoticus. Moose River sandstone, Detroit, Somerset County, Maine. 

21. Chonetes novascoticus Hall var. canadensis Biliings. A large pedicle valve preserving the exterior of the shell. 

This specimen in its roimded flexuous strire and appearance(?) of a midrib recalls C. striatissimus sp. nov. Moose 

River sandstone, same locality as figure 20. · 

314 . 
U. S. GEOLOGICAL SURVEY PROFESSIONAL PAPER 89 PLATE IX 

1 

2 

3 

4 

5 6 

7 

9 

8 

20 

11 

10 

12 13 

14 21 15 

17 18 

16 19 
U.S. GEOLOGICAL SURVEY PROFESSIONAL PAPER 89 PLATE X 

1 2 

3 

5 

4 

7 8 9 10 

6 

15 

12 13 14 

11 

17 18 19 

16 21 

22 

20 

24 

27 28 23 

25 26 

29 

30 

31 32 33 
PLATE X. 

[All the figures on this plate are of approximately natural size.] 

Figures 1, 2, 3, 5-16, 18-29, 32, 33, Chonetes novascoticus Hall (p. 45). (See also Pl. IX, figs. 1-10, 13, 14, 17, 18.) 

Flguro 4, Chonostrophia complanata Hall (p. 55). 

Flguro 17, Chonetes striatissimus sp. nov. (p. 44). (See also Pl. VIII, fig. 24; Pl. IX, figs. 1-10, 13, 14, 17, 18.) 

FJgu.ros 30, 31, Chonetes novascoticus Hall var. canadensis Billings (p. 49). (See also Pl. IX, figs. 20, 21; Pl. XI, fig. 16.) 

1-3. Chonetes novascoticus Hall. Three small pedicle valves in internal mold. Figure 3 shows obscure indications 

of a midrib. Figure 1 shows same specimen as Plate IX, figure 12; figure 2 same as Plate IX, figure 15. Chapman sandstone, west side of Edmunds Hill, Chapman Township, Aroostook County, Maine. 

4. Chonostrophia con,planata Hall. Partial interior cast and exterior mold of a brachial valve of flat, slightly 

resupinate convexity. Moose River sandstone, Detroit, Somerset County, Maine. 

5. Chonetes novascoticus Hall. Exterior cast of characteristic pedicle valve, showing the coarse strire (relatively coarse 

compared with those of C. striatissim,us), depressed convexity, absence of midrib, and cardinal spines apparently 

complete on the left side. Chapman sandstone, same locality as figure 1. 

6. Chonetes novascoticus Hall. A pedicle valve in internal mold (upper shell) and a concave brachial valve in external 

mold (lower shell), showing the usual size of the species. Chapman sandstone, same locality as :figure 1. 

7. Chonetes novascoticus Hall. A pedicle valve in internal mold, with five spines on one side. Chapman sandstone, 

same locality as figure 1. 

8. Chonetes novascoticus Hall. A pedicle valve in external mold. A single median strla seems to be a trifle stronger 

than the others. Chapman sandstone, same locality as figure 1. 

9-15. Chonetes novascoticus Hall. Pedicle valves of medium to rather small size, all in internal mold except that 

shown in figute 13, which is an external mold. Chapman sandstone, same locality as figure 1. 

:t.G. Chonetes novascoticus Hall. Brachial valve in external mold. Chapman sandstone, same locality as :figure 1. 

17. Chonetes striatissimus sp. nov. An, exfoliated shell or internal mold, preserving the midrib and fine striation. 

Same specimen as Plate IX, figure 4. Chapman sandstone, 2l miles west of Presque Isle Stream, Chapman 

Township, Aroostook County, Maine. · 

18-21. Chonetes novascotiG'US Hall. Pedicle valves in external mold (figs. 18, 20) and internal mold (figs. 19, 21). 

Chapman sandstone, same locality as figure 1. 

22-26. Chonetes novascoticus Hall. Brachial valves in internal mold, showing the bifid cardinal process, the dental 

sockets and crural bases, and the blunt median and lateral ridges. Chapman sandstone, same locality as figure 1. 

27-29. Chonetes novascoticus Hall. Pedicle valves in internal mold. Chapman sandstone, same locality as figure 1. 

30. Chonetes novascoticus Hall var. canadensis Billings. A flattish brachial valve in external mold showing the 

strongly bifid cardinal process. Note the remarkable curve of the strire in the middle; this appears to have 

been clue to an injury to the shell during the life of the animal. Moose River sandstone, Detroit, Somerset 

County, Maine. 

31. ?Chonetes novascoticus Hall var. canadensis Billings. A large, very depressed convex specimen, apparently the 

external mold of a Chonetes referred here on account of its large size. Moose River sandstone, same locality 

as figure 30. 

32. Chonetes novascoticus Hall. A brachial valve similar to those shovvn in figures 22-26. Chapman sandstone, same 

locality as figure 1. 

33. Chonetes novascoticus Hall. A broad pedicle valve in external mold, with S pir'if er eyclopterus. Chapman sandstone, 

same locality as figure 1. 

315 
PLATE XL 

[All the figures on this plate are of approximately natural size except figures 16 and 17, which are enlarged 2 diameters.) 

Figures 1-15, Rensselaeria mainensis Williams (p. 72). (See also Pl. VI, fig. 11.) 

Figure 16, Chonetes novascoticus Hall var. canadensis Billings (p. 49). (See also Pl. IX, fig~. 20, 21; Pl. X, figs. 30, 3"!.) 

Figure 17, Leptostrophia perplana 9onrad (p. 27). (See also Pl. III, fig. 9; Pl. VII~, figs. 1-7, 13-16.) 

1-3. Rensselaeria mainensis Williams. Dorsal, ventral, and lateral views of the type specimen, preserVing the shellr 

showing the outline, convexity, and' especially the strong ribs, and in the pedicle valve the cardinal area and. 

elevated beak with perforate apex. Chapman sandstone, Presque Isle Stream, Chapman Township, Aroostook. 

County, Maine. 

4. Rensselaeria mainensis Williams. A large pedicle valve retaining parts of the shell, showing the ventricose .and 

elevated beak, the "parabolic" profile, and the strong continuous simple ribs. Chapman sandstone, 2~ miles. 

west of Presque Isle Stream, Chapman Township, Aroostook County, Maine. 

5. Rensselaeria mainensis Williams. Pedicle valve, internal mold, showing the large, strongly impressed musculature, 

the cardinal area, and the presence of the ribs on the interior (except about the musculature). The aspect of 

the cardinal area indicates that the cavity on the inside had been filled in solid by the thickening of the shell. 

Note at the apex the sand filling of the circular foramen. Chapman sandstone, Presque Isle Stream at end of 

Tweedy road, Chapman Township, Aroostook County, Maine. 

6. Rensselaeria mainensis Williams. Same specimen as figure 4, cardinal view, showing the high, very distinct cardinal 

area, the delthyrl.:um, and the circular apical foramen. 

7. Rensselaeria main.ensis Williams. Pedicle valve in internal mold, showing plica ted interior and musculature. 

Note the vertical pedicle area seen in perspective. The aspect of the cardinal area indicates that this valve had. 

been enormously thickened on the interior along the uinbonal slopes. Chapman sandstone, same locality as. 

figure 5. - . 

8. Rensselaeria mainensis Williams. Lateral view of specimen shown in figure· 7, showing the erect, large pedicle area. 

Chapman sandstone, same locality as figure 5. 

9. Rensselaeria mainensis Williams. Pedicle valve in internal mold, showing the cardinal area in which the shell is 

only slightly thickened on the interior. This figure in comparison with figure 7 shows the variability in the size, 

of the ribs. Chapman sandstone, same locality as figure 5. 

10. Rensselaeria mainensis Williams. Internal mold of a pedicle valve, with the cardinal area indicating only a slight 

thickening of the shell. Compare with figures 5, 7, and 9 and note variability in the appearance of the musculature. Chapman sandstone, same locality as figure 5. . 

11, 12. Rensselaeria mainensis Williams. Wax impressions from the original of figure 7, shoWing the characteristic 

cardinal area and erect beak of the species. Chapman sandstone, same locality as figure 5. 

13, 14. Rensselaeria mainensis Williams. Interior molds of two small pedicle valves, showing the incisions left by the." 

dentallamellre. Chapman sandstone, same locality as figure 5. 

15. Rensselaeria mainensis Williams. Brachial valve in internal mold, showing the horizontal poster.ior margin, strong· 

musculature, faint median septum, and the filling of the "visceral canal" or tunnel through the massive hinge 

plate. Chapman sandstone, same locality as figure 5. 

16. Chonetes novascoticus Hall var. canadensis Billings. Exterior cast of a large depressed pedicle valv~. X 2. .Moose· ' 

River sandstone, Detroit, Somerset. County, Maine. 

17. Beptostrophia perplana Hall. Pedicle valve, in internal mold, of a typical specimen of the form of the species called 

L .. blainvillei Billings, showing the medium size and obtuse musculature. X 2. Moose River sandstone, same 

locality as figure 16. 

316 
U.S. GEOLOGICAL SURVEY PROFESSIONAL PAPER 89 PLATE XI 

1 2 

~ 

. f . 

;,.. . 

!. .'f! i ' 

3 

4 

5 

7 

10 

6 

8 9 

11 

16 12 

13 

14 

15 

17 
U. S. GEOLOGICAL SU RVEY PROFESSIONAL PAPER 89 f:'LATE XII 

1 4 

2 

3 

8 

9 7 6 

5 

10 

11 12 

Fi 

14 16 17 

13 

20 

19 21 

18 22 23 

28 

24 25 2(i 27 
PLATE XII. 

[All the figures on this plato are or natural size, except figures 2, 3, 11, and 13, which are magnified 2 di~meters.) 

'Figures 1-15, llolopea (Auriptygma) beushauseni Clarke (p. 281). 

Figure 16, Pseudotectus1 sp. indet. (p. 279). 

Figure 17, Pseudotectus hitchcocki (Clarke) (p. 278). 

Figures 18-27, Pseudotectus1 deciduus sp. nov. (p. 278) . 

. Figure 28, Goniostropha chapmani sp. nov. (p. 276). 

1. Ifolopea (Attriptygma) beushauseni Clarke. Interior mold, showing outer whorl. Presque Isle Stream, Chapman 

Township, Aroostook County, Maine. 

2. Holopea (Auriptygma) beushauseni Clarke. Interior mold, showing two whorls and flaring lip of the body whorl. 

X 2. Presque Isle Stream, at end of Tweedy road, Chapman Township, . .A:roostook County, Maine . 

. s. Holopea (Auriptygma) beushauseni Clarke. Interior mold, showing four whorls. X 2. Two miles west of Presque 

Isle Stream, Chapman Township, Aroostook County, Maine. 

·4. Holopea (Auriptygma) beushauseni.Clarke. Body whorl. Same locality as figure 3. 

5. Holopea (Attriptygma) beusha'useni Clarke. A sandstone mold, possibly of exterior, showing six whorls, probably 

of this species. Same locality as figure 3. 

6-9. ]Jolopea (Attriptygma) beusha1tseni Clarke. Interior molds, showing various expressions of form, partly due to 

different degrees of removal of matrix. Same locality as figure 3. . 

'10. Holopea ('Auriptygma) beushauseni Clarke. Internal mold, showing bluntly carinated form of the outer whorl. 

Same locality as figure 2. 

11. Holopea (Auriptygma) beushauseni Clarke. Outer 'Yhorl, showing flaring lip~ X 2. Edmunds Hill, Chapman 

'fownshi,p, Aroostook County, Maine. 

12. Holopea (AuTiptygma)' beusha1tseni Clarke. A faint impression of a small shell in sandstone, presenting some 

resemblance to the mold shown in figure 5, and probably this species. The outlines and divisions between 

whorls are stronger in the figures than in the. specimens. Sall!e locality as figure. 3. . 

13,. Holopea (A1triptygma) beushauseni:C~ru:k~.. A somewhat crushed interior mold, showing the flaring lip of outer 

whorl. ·. X 2. Same locality as figure 3... · . 

'14. Holopea (A-uriptygma) beushauseni Clarke. A specimen in which the outer portion of the body whorl appears to 

be slightly contracted in diameter. Same locality as figure 3. . . 

15. Holopea (Auriptygma) beushauseni Clarke. Outer whor1 of a medium-sized specimen, mold of interior. West side 

of Edmunds Hill, Chapman Township, Aroostook County, Maine. 

'16. Pseudotect1ts f sp. indet. A faint mold in sandstone, representing three whorls, the outer one of ·which is sharply 

' angulated .. The outlines are too deeply drawn in the figure; the specific cll;aracters are indistinct. Same 

locality as figure 3. · 

17. Pse1tdotec~1ts hitchcocki (Clarke). Gutta-percha impression of the exterior of a complete shell, showing the four 

whorl~:?, the ca~inated outer edge of the whorl filling in the suture and the rapidly expanding form of the spire. 

The impression does not show the outer edge of the body whorl. Same locality as figure 3. 

18. Pseudotectus? decid1tus sp. nov. A medium-sized specimen, mainly mold of the interior, but showing a part of 

exterior of the outer whorl and the carination of the interior of the body whorl. Same locality as figure 3. 

19-21. Pse1tdotectusf deciduus sp. nov. Molds of the interior of small specimens, showing the distinct carination of 

. the body whorl, the earlier whorls not showing carination on the interior. Same locality as figure 3. · 

'22. Pse1tdotect1tsf decidttus sp. nov. Internal mold, showing the carination only upon the outer part of the body 

whorl. Same locality as figure 3. 

23. Pse'ttdote.ctus? decid'ttUS sp. nov. Internal mold of body whorl, showing the carination only in outer part of whorl. 

·Two and one-half miles west of Presque Isle Stream1 Chapman Township, Aroostook County, Maine. 

24-27. Pse1tdotect1ts? deciduus sp. nov; Interior molds, showing various degrees of expression of the carination upon 

the interior surface of the shell and the shape of the mouth aperture. Same locality as figure 3. 

28. Goniostropha chapmani sp. nov. Interior mold, showing four whorls. Same locality as figure 3. 

All from the Chapman sandstone. · 

317 
PLATE XIII. 

[All the figures on this plate are of natural size.] 

Figure11l, 4, Loxonemajerseyense Weller (p. 280). 

Figure 1a, Coolidium cf. Loxonema planoJyrata Hall (p. 275). 

Figures 2, 3, 5, Loxonema welleriana sp. nov. (p. 279). 

Figures 6-11, Mesocrelia tenuella sp. nov. (p. 273). 

Figures 12, 16, Platyceras chapmani sp. nov. (p. 259). 

Figure 13, Strophostylus cf. S. globosus Hall (p. 263). 

Figure 14, Platyceras (Orthonychia) hebes var. p (p. 261). 

Fi~,rures 15, 18, Platyostoma ventricosum Conrad (p. 262). 

Figure 17, Orthoceras princiana sp. nov. (p. 282). 

Figure 19, Platyceras edmundi sp. nov. (p. 260). 

Figure 20, Platyceras (Orthonychia) hebes Clarke (p. 260). 

Figure 21, Orthoceras cf. 0. parlinense sp. nov. (p. 283). 

Figures 22, 23, Platyceras (Orthonychia) aroostooki sp. nov: (p. 261). 

Figure 24, Platyceras (Orthonychia) compressa sp. nov. (p. 262). 

Figure 25, Orthoceras parlinense sp. nov. (p. 2!>3). 

Figure 26, Platyceras (Orthonychia) hebes var. a: (p. 260). 

1. Loxonema jerseyense Weller .. Mold of interior, showing four whorls. Moose River sandstone, Detroit, Somerset 

County, Maine. 

1a. Crelidium cf. Loxonema planogyrata Hall. Mold of interior, showing the a1igular character of the whorls. 

Chapman sandstone. Presque Isle Stream, near end of Tweedy road, Chapman Township, Aroostook County, 

Maine. · 

2. Loxonema welleriana sp. nov. Exterior of a nearly complete specimen, showing the surface markings. Moose River 

sandstone, same locality as figure 1. 

3. Loxonema welleriana sp. nov. Exterior of small specimen, showing external markings. Moose River sandstone, 

same locality as figure 1. 

4. Loxonemajerseyense Weller. Exterior of specimen, showing surface markings. Same locality as figure 1. 

5. Loxonema welleriana sp. nov. Impression of the exterior in sandstone matrix, showing the initial portion of the 

spire of a nearly complete specimen with 12 whorls. Moose River sandstone, same locality as figure 1. 

6-11. Mesoccelia tenuella sp. nov. Molds of the interior of several specimens, showing slight difference in size. Figures 

9 and 10 show more distinctly than the others the slight angularity of the inner surface ofthe whorls.' 'Chapman 

sandstone; figs. 6, 9, 10, and 11 from locality 2 miles west of Presque Isle Stream, 7 and 8 from Presql.i.e Isle Stream, 

Chapman Township, Aroostook County, Maine. . 

12. Platyceras chapmani sp. nov. Internal mold, showing the broad sulcus on the outer side of the body whorl. Chapman sandstone, Edmunds Hill, Chapman Township, Aroostook County, Maine. · · 

13. Strophostylus cf. S. globosus· Hall. Side view of the specimen, showing depressed whorls and trace of columellar 

twisting characteristic of Strophostylus. Chapman sandstone, west side of Edmunds Hill, Chapman Township, 

Aroostook County, Maine. 

14. Platyceras (Orthonychia) hebes var. [3. A young specimen not exhibiting the specific·characters of the adult form, 

but referred to the same species on account of its similarity to the early stages of growth of the type. Chapman 

sandstone, same locality as figure 13. . · 

15. Platyostoma ventricosum Conrad. A small specimen viewed at right angles to the axis of the shell, apparently 

representing the younger portion of the same species as the form shown in figure \8. Moose River sand'3tone, 

same locality as figure 1. 

16. Platyceras chapmani sp. nov. Interior mold of a smaller specimen than that of figure 12, showing sulcus over part 

of the inner half of the body whorl as well as on the outer side, suggesting the explanation as a local thickening 

of the shell. Chapman ~andstone, same locality as figure 12. 

17. Orthoceras princiana sp. nov. Specimens showing four chambers in the midpart of the shell. Moose River sandstone, same locality as figure 1. 

18. Platyostoma ventricosum Conrad. A large specimen viewed from the apical end, showing the body whorl rapidly 

expanding, the surface markings, and the revolving undulations affecting the outer part of the body while the 

early stages of growth are not undulate. Moose River sandstone, same locality as figure 1. 

19. Platyceras edmundi sp. nov. A specimen showing the low spire and the sulcation on inner side of the body whorl. 

Chapman sandstone, same locality as figure 12. 

20. Platyceras (Orthonychia) hebes Clarke. A specimen presenting the characters of Clarke's species from the same 

locality, figured from a slightly different angle from that of his figures. Chapman sandstone, same locality as 

figure 13. 

318 
U. S. GEOLOGICAL SURVEY PROFESSIONAL PAPER 89 PLATE XIII 

1a 3 

4 

1 

5 

6 8 9 10 

11 

7 

14 

12 13 15 16 

19 20 

18 

17 

24 

21 

25 

22 23 26 
PLATE XIII. 319 

21. Orthocera.s cf. 0. parl·inense sp. nov. Specimens showing mold of interior of six chambers., Moose River sandstone, same locality as figure 1. 

22. Platyceras (Orthonychia) aroostooki sp. nov. A specimen showing the outer side of the shell opposite the aperture, 

the almost straight growth, and the angular expression of the body part of the shell. -Chapman sandstone, same 

locality as figure 12. 

23. Platyceras (Orthonychia) aroostooki sp. nov. Opposite side of the specimen shown in figure 22, showing the slight 

coiling of the initial portion of the shell, and the oval,· elongate aperture. Chapman sandstone, same locality 

as figure 12. 

24. Platyceras (Orthonychia) compressa sp. nov. A short specimen, with the same almost straight conical form asP. (0.) 

aroostooki, but with more compressed aperture. Chapman sandstone, same locality as figure 13. 

25. Ortlwceras parlinense sp. nov. A small specimen, showing eleven chambers; the type specimen of the species. 

Moose River sa.ndstone, Somerset CQ1mty, Maine, probably from the ledge along the side of Parlin Pond. 

26. Platyceras (Orthonychia) hebes var. a. A specimen corresponding to the apical portion of the type species. Chapman 

sn.ndstone, same locality as figure 13. 
PLATE XIV. 

[All the figures on this plate are of natural size except as otherwise indicated.] 

Figures 1, 1a, 1b, 12, 13, 17-19, 28, Bellerophon (Plectonotus) trilobatus Sowerby (p. 266). 

Figures 2, 11, Tropidodiscus minimus var. americanus var. nov. (p. 272). 

Figures 3-10, 16, 21, Tropidodiscus obex Clarke (p. 270). · 

Figures 14, 15, 20, 27, Bellerophon (Patellostium) revolvens sp. nov. (p. 265). 

Figure 22, Tropidodiscus ( Temnodiscus) somerseti sp. nov. (p. 271). 

·Figures 23, 24, Tentaculites schlotheimi Koken (p. 283). 

Figure 25, Cornuliies serpularius Schlotheim (p. 15). 

Figure 26, Tentaculites cf. T. elongatus Hall (p. 284). 

Figure 29, Cornulites (Ortonia) mainensis sp. nov. (p. 16). 

1. Bellerophon (Plectonotus) trilobatus Sowerby. A large specimen showing the shape of the outer whorl and the sinus 

cutting into the middle of the outer lip of the median lobe. Moose River sandstone, Somerset County, Maine. 

la. Bellerophon (Plectonotus) trilobatus Sowerby. Opposite view of the specimen shown in figure 1, showing the inner 

part of the outer whorl._ Moose River sandstone, same locality as figure 1. 

lb. Beller:ophon (Plectonotus) trilobatus Sowerby. A mold of the exterior of the outer whorl of a mature specimen, 

showing the sl.it .band in center of the middle lobe. Moose River sandstone, same ~ocality as figure 1. 

2. Tropidodiscus minimus var. americanus var. nov. A view of the front of a small specimen, showing the shape of the 

body whorl at the mouth. X 2. The same specimen is represented in figure 11. Chapman sandstone, 2 miles 

west of Presque lsle stream, Chapman Township, Aroostook County, Maine. 

3. Tropidodiscus obex Clarke. Cancellation of the external surface, showing the ornamentation of a very well preserved specimen. X 5. Chapman sandstone, Edmunds Rill, Chapman Township, Aroostook County, Ma.ine. 

4. Tropidodiscus obex Clarke. A lateral view of a complete shell. Chapman sandstone, same locality as figure 3. 

5. Tropidodisc'l.,tS obex Clarke.· Mold of the umbilicus. X 2. Chapman sandstone, same lo~al.ity as figure 3. 

6. Tropidodiscus obex Clarke. Mold of the inner face of the outer whorl, showing the groove formed by the ihne.r coil. 

Chapman sandstone, same locality as figure 3. · 

7. Tropidodiscus obex Clarke. Dorsal view of a small specimen. Chapman sandstone, same locality as figure 3. 

8, 9. Tropidodiscus obex Clarke. Dorsal and lateral views of another nearly perfect specimen. Chapman sandstone, 

same locality as figure 3. 

10. Tropidodiscus obex Clarke. Dorsal view of the spedmen shown in figure 4. Chapman sandstone, same locality as 

figure 4. 

11. Tropidodiscus minimus var. americanus var. nov. A lateral view of the coiled shell. Chapman sandstone, same 

locality as figure 2. 

12. Bellerophon (Plectonotus) triloba.tus Sowerby. A small specimen, lateral view, showing the latuallobe separated 

by regular impressed groove from the outer lobe. Chapman sandstone, same locality as figure 2. 

13. Bellerophon (Plectonotus) trilobatus Sowerby. A somewhat larger spedmen showing the median lobe and .the 

expansion at the open end of the shell. Chapman sandstone, same locality as figure 2. 

14, 15, 20, 27. Bellerophon (Patellostium) revolvens sp. nov. Specimens of varying size exhibiting the characterl.stics 

of the species. Figures 15 and 20 show the inner and exterior molds of the same (the type) specimen, showing 

the .evenly rounded body whorl and the broadly flaring mouth, with sulcus in the outer lip. Moose River 

sandstone, Detroit, Somerset County, Maine. 

16. Tropidodiscus obex Clarke. A specimen of the same outline as the typical Chapman form but with groove above 

the bulging umbilical ridge. Compare with figure 4. Moose River sandstone, same locality as figure 14. 

17. Bellerophon (Plectonotus) trilobatus Sowerby. Another specimen, lateral view. Chapman sandstone, same 

locality as figure 2. 

18. Bellerophon (Plectonotus) triloba,tus Sowerby. .Another specimen of about the same size as that shown in figure 12, 

showing the flattened median lobe and narrow lateral lobes. Chapman sandstone, same locality as figure 2. 

19. Bellerophon (Plectonotus) trilobatus Sowerby. A specimen of the same size and form as that shown in figure 13. 

Moose River sandstone, same locality as figure 14. 

20. See figure 14. 

21. Tropidodiscus obex Cl~rke. A small specimen showing the shape of the umbilicus and smaller whorls of the shell. 

Chapman sandstone, same locality as figure 3. o 

22. Tropidodiscus ( Temnodiscus) somerseti sp. nov. A large specimen showing part of the outer whorl and umbilical 

cavity but broken at the front. Moose River sa;ndstone, same locality as figure 14. 

23, 24. Tentaculites schlotheimi Koken. Two specimens in sandstone, showing the shape and size of the cone and the 

rings of the surface, but not the surface m..'\rkings,': Chapman sandstone, west side of Edmunds Hill, Chapman 

Township, Aroostook County, Maine.· 

320 
U. S. GEOLOGICAL SURVEY PROFESSIONAL PAPER 89 PLATE XIV 

1a 

• 3 

4 

2 

:) 6 

lb 

11 

9 

12 

7 8 10 

13 14 15 

16 17 

18 

19 

20 21 

22 

23 

27 28 

24 

25 26 29 
PLATE XIV. 321 

25. Cornulites serpularius Schlotheim. A fragment showing the characteristics of the species, partly embedded in· 

sa.ndstone. Chapman sandstone, same locality as figure 3. 

2G. 'l'entaculites cf. T. elongatus Hall. A slab of sandstone showing several specimens, some of them larger than the 

Chapman specimens; and smaller than Tentaculites elongatus, which they also closely resemble. Moose River 

sandstone, same locality as figure 14. 

27. See figure 14. 

28. Bellerophon (Plectonotus) trilobatus Sowerby. A small, narrow specimen showing the shape of the shell in young 

st.'tge of growth. Chapman sandstone, same locality as figure 2. 

29. Cornulites (Ortonia) mainensis sp. nov. A specimen showing the small conical shells attached to the surface of a 

Chonetes. Moose River sandstone, same locality as figure 14. 

50245°-No. 89-16-21 
PLATE XV. 

[All the figures on this plate are of natural size.] 

Figures 1-17, Actinopterella radialis (Clarke) (p. 184). 

Figures 1S-23, Actinopterella aroostooki (Ciarke) (p. 187). 

1. Actinopterella radialis (Clarke). Mold of interior of a right valve, showing the hinge area and teeth and anterior 

muscular impression. Chapman sandstone, Presque Isle Stream, Chapman Township, Aroostook County 

Maine. 

2. Actinopterella radialis (Clarke). Exterior of a left valve, showing hinge area, hinge teeth and nnterior muscular 

scar, and surface markings. Chapman sandstone, same locality as figure 1. . 

3-7. Actinopterella radialis (Clarke). Exterior of. left valves, showing considerable difference in shape, size, and 

proportions. Chapman sandstone, same locality as figure 1. 

8-10. Actinopterella radialis (Clarke). Different views of a single ·specimen of a mold of interior of both valves. 

Figure 8 shows view from front, both valves convex, though. left valve more convex than right; figure 9, view 

from apical end, showing similarity of the two valves; figure 10, mold of interior of right valve. Chapman 

sandstone, sam6 locality .as figure 1. 

II. Actinopterella radialis (Clarke). · Left valve, showing an~erior teeth and muscular scar. Chapman sandstone, 

same locality as figure 1. 

12. Actinopterella radialis (Clarke). Left valve, showing broad umbonal region and rather small posterior wing, 

Chapman sandstone, same locality as figure 1. 

13. Actinopterella radialis (Clarke). Left valve, showing both concentric and radial surface markings, mucronate 

· extension of posterior wing, and posterio~ tooth. Chapman sandstone, same locality as figure 1. 

14-17. Actinopterella radialis (Clarke). Four views of the same specimen, showing convexity of both valves but some 

d~fference in relative size, especially at early stage 0f growth. Chapman sandstone, same locality as figure 1. 

18-21. Actinopterella aroostooki (Cla,rke). Exterior views of left valves, showing the coarse surface marking, extending over the wings as well as the body of the shell. Chapman sandstone, west side of Edmunds Hill, Chapman Township, Aroostook County, Maine. 

22. Actinopterella aroo;took1' (Clarke). Mold of exterior of left valve. Chapman sandstone, same locality as figure 18. 

23. Actinopterella aroostooki (Clarke). Mold of interior of right valve, in which the posterior hinge tooth and the 

exterior surface markings are impressed. Chapman sandstone, same locality as figure 18. 

322 
U. S. GEOLOGICAL SURVEY PROFESSIONAL. PAPER 89 PLATE XV 

3 2 

1 

4 

5 6 7 

10 9 8 

11 

13 

12 14 

15 

18 

19 

17 16 

20 21 22 23 
U. S. GEOLOGICAL SURVEY PROFESSIONA L PAPER 89 PLATE XVI 

2 

l 

4 

6 5 
PLATE XVI. 

[All the figures on this plate are of natural size.] 

Ffg~,lj_6;, {C'IH.''.IJan'f!~!..lf!; "ra.i"."~'11:si.?, (Cl~rko) (p. 179). 

1. Follmannella mainensis (Clarke). Interior of a left valve in which the exterior markings are shown through the 

outer layer of the shell but do not affect the inner layers. The mature form of the shell is shown in this specimen. Moose River sandstone, Detroit, Somerset County, Maine. 

2. Follmannella mainensis (Clarke). An immature left valve, showing the characteristic surface markings over the 

body and on the wing. Moose River sandstone, same locality as figure 1. 

3. Follmannella mainensis (Clarke). Mold of interior of left valve, showing the hinge teeth and anterior muscular 

scar. Moose River sandstone, same locality as figure 1. .. 

4. Folbnannella mainensis (Clarke). Exterior of a left valve, similar to that shown in figure 3. Moose River sandstone, same locality as figure 1. 

5. Follmannella mainensis (Clarke). An exfoliated left valve of a mature massive specimen. Varietally differing 

from the typical sp.ecimens shown in figures 1 to 4, but presenting the same characters of general form. The 

concentric lines are too strongly represented in the figure; only· the in:riermost layers of the shell are present 

and only on a part of the original specimen. Moose River sandstone, same locality as figure 1. 

6. Follmannclla mainensis (Clarke). An exfoliated and crushed specimen of a mature left valve, showing the inner 

layers of shell without the characteristic surface markings of the outer layers. Moose River sandstone, same 

locality as figure 1. 

323 
PLATE XVII. 

[All the figures on this plate are of natural size.~ 

Figures 1-11, Follmannezla mainensi.s (Clarke} (p. 179}. 

Figure 12, Actinopterella concentrica sp. nov. (p. 190}. 

Figure 13, Actinopterella aroostooki var. planicosta var. nov. (p. 190). 

Figures 14-16, Actinoptcrella aroostooki (Clarke) (p. 187). 

Figure 17, Actinopterella aroostooki var. erecta var. nov. (p. 189). 

Figure 18, Actinopterella tenuiradiata sp. nov. (p. 191)." 

1. Follmannella mainensis (Clarke). A medium-sized left valve, showing the characteristic surface markings over 

the body and the contour of the posterior part of an immature shell and the posterior wing. Moose River sandstone, Detroit, Somerset County, Maine . 

. 2. Follmannella mainensis (Clarke). An exfoliated left valve, showing the outline and the beginning of retral extension of the basal part of the shell. Moose River sandst.one, same locality as figure 1. 

:3. Follmannella mainensis (Clarke). A small left valve of narrow, elongate form, exhibiting surface markings but 

not the retral extension of the base, characteristic of adult shells. Moose River sandstone, same locality· as 

· figure 1. 

4. Follmannella mainensis (Clarke). A small broad form, exhibiting the characteristic surface markings but not the 

characteristic form of mature shells. Moose River sandstone, same locality as figure 1. · 

1 -5. Follmannella mainensis (Clarke). A medium-sized left valve in which the mature characteristics-of form have 

been assumed early in growth· and are ~:xpressed in extreme dev.elopment. Moose River sandstone, same 

locality as figure 1. 

' ·6. Follmannella mainensis (Clarke). A small ~rect form, showing surface markings on the front part of the shell, and 

by removal of shell over the umbonal region exhibiting the hinge teeth and anterior muscular scar. Moose 

River sandstone, same locality as figure 1. 

·1. Follmanne.lla mainensis (Clarke). !Yfold of interior of left valve, showing .the hinge teeth and anterior muscular 

scar. Moose Riyer sandstone, same locality as figure 1. 

8. Follmannella mainensis (Clarke). Mold of interior of left valve, showing hinge teeth and both muscular scars .• 

Moose River sandstone, same locality as figure 1. 

9. Follmannella mainensis (Clarke). Mold of interior of right valve, showing the hinge teeth, anterior muscular scar, 

concave form of that valve, and faint impressions of radial markings on the interior of the basal part of the 

shell. These markings are very faint on the original, and their strength and regularity are exaggerated in 

the figure. No specimens showing the exterior of the right valve have beeri seen. Moose River sandsto~e, 

same locality as figure 1. · 

10. F8llmannella mainensis (Clarke). A partly exfoliated left valve. In the central part of the shell the superficial 

radial lineation is conspicuous. Near the basal margin the concentric lines dominate, showing the deeper 

layers of the shell, the surface having been removed. Moose River sandstone, same locality as figure 1. 

11. Follmannella mainensis (Clarke). A small specimen. The slightly greater coarseness of the radial lineation is 

due to removal of the outer layer·of the shell, on which the finer intercalated radial lines are better exhibited. 

Moose River sandstone, same locality as figure 1. 

12. Actinopterella concentrica sp. nov. An imperfect specimen of a left valve, showing the posterior part of the shell 

and its characteristic surface sculpture. The high arching of the umbonal and central part of the shell are not 

correctly reproduced by the figure. Chapman sandstone, west side of Edmunds ]Iill, Chapman Township, 

Aroostook County, Maine. 

13. Actinopterella aroostooki var. planicosta var. n_ov .. An imperfect specimen of a left valve, showing the form and 

surface character of the variety. Chapman sandstone, Edmunds Hill, Chapman Township, Aroostook· County, 

Maine. · 

14. Actinopterella aroostooki (Clarke). An erect specimen, showing the characteristic markings of the species. Chapman sandstone, same locality as figure 12. (See also Pl. XV, figs. 18-23.) 

15. Actinopterella aroostooki (Clarke). A specimen showing the lineation on the posterior wing. Same locality 

as figure 14: 

16. Actinopterella aroostooki (Clarke). A right valve, showing both wings, the posterior hinge tooth, the anterior 

muscular scar, and the characteristic convexity. Chapman sandstone, same locality as figure 12. 

17 .. Actinopterella aroostooki var. erecta var. nov. The type specimen of the variety, a left valve in which the broad 

and depressed convex umbonal region and coarser radial lineation are exhibited. Chapman sandstone, 2! 

miles west of'Presque Isle Stream, Chapman 'l'ownship, Aroostook County, Maine. 

18. Actinopterella tenu-i,radiata sp. nov. Mold of interior of left valve, showing the highly arched cylindrical body 

portion of the shell, the strong posterior hinge teeth, and the faintly impressed radial lineation, implying a distinct lineation on the exterior of the shell, although no exterior of this species has been seen. Moose River 

sandstone, Detroi~, Somerset County, Maine. · 

324 
U. S. GEOLOG ICAL SURVEY 

6 

• ) 

0 

11 

17 

7 

2 

10 

12 

14 

15 

PROFESSIONAL PAPER 89 PLATE XVII 

1 

4 

8 

9 

13 

16 18 
U. S. GEOLOGICAL SURVEY PROFESSIONAL PAPER 89 PLATE XVIII 

1 2 3 

5 6 

8 9 

7 

10 11 12 
PLATE XVIII. 

[All the figures on this pln.tc n.re of natural size.) 

Figures 1-6, 8, 11, .M"yalina maureriana sp. nov. (p. 213). 

Figures 7, ll, 10, 12, .Myalina maureriana var. lata var. nov. (p. 215). 

1. J,fyalinct ntattreriana sp. nov. Mold of the interior of a right valve, with part of the shell preserved across the· 

middle part of the valve. The flat striated hinge, the small deep pit of the ant~rior muscular scar, and a little 

of the pallial line arc visible. Chapman sandstone, Presque Isle Stream, Chapman Township, Aroostook 

County, Maine. · · 

2. Jfyal·ina maureriana sp. nov. Gutta-pcrcha impression of the mold of the exterior of a left valve, showing the 

surface character and the beak projected slightly beyond the edge of the hinge. Chapman sandstone, same 

locality as figure l. 

3. J,fyalina rnaureriana sp. nov. A specimen of a right.' valve showing the posterior muscular scar and mantle. 

Chapman sandstone, same locality us figure 1. 

4. Myal·ina. rna.ureriana sp. nov.~ Mold of the interior of a right valve, showing part of the hinge area., the outline 

of the edge of the mantle and the posterior muscular scar near the middle and the anterior muscular scar at the 

hinge margin. Chapman sandstone, same locality as figure 1. 

5. J,fyal·ina rnattreriana sp. nov. A specimen similar to that shown in figure 4, but somewhat more slcnder.and 

elongate, in which only the posterior scar is visible. Chapman sandstone, same locality as figure 1. · 

G. },fyal·ina m.aureriana sp. nov. Mold of the interior of a right valve. 

7. J,fyalina rnaureriana va.r. lata var. nov. A partly exfoliated right valve, showing the characteristic widening of 

the front part of the shell and the surface sculpture (on the left). Chapman sandstone, Presque Isle Stream, 

Chapmn.n Township, Aroostook County, Maine. 

8. Uyalina maureriana sp. nov. A small left valve, which apparently from thinness of the shell has left the impression of the surface sculpture on the matrix. In the specimen the shell substance is entirely removed. 

Chapman sandstone, same locality as figure 1. 

9. J,fyalina mattreriana var. lata var. nov. Mold of interior of left valve, showing outline of mantle but no distinct 

evidence of muscular attachments. Chapman sandstone, same locality as figure 7. 

10. Jfyalina 7rWttreriana var. lata var. nov. Mold of interior of a small right valve in which the pallial margin is evident but no distinct impression of muscular scar. Chapman sandstone, same locality as figure 7. 

11. Myalina rnaureriana sr). nov. Exterior surface of a right valve, somewhat exfoliated but exhibiting the rough 

surface of a mature shell. Chapman sandstone, same locality as figure 1. 

12. Myal•ina maureriana va.r. lata var. nov. Exterior of a left valve, showing the characteristic broadening of the 

anterior p~ut of the shell of this variety a.s contrasted with the slightly broadened form of the typical species 

shown in figure 11. Chapman sandstone, same locality as figure 7. 

32'5 

. .:. ........ ....,~~ . 
PLATE XIX. 

[All the ftgures on this plate are of natural size except figures 4, 7, and 8, whlch are enlarged. 1~ diameters.] 

Figure 1, Cleidophorus curtus sp. nov. (p. 160). 

Figure 2, Orthodesma carinifera sp. nov. (p. 126). 

Figures 3, 9, 11, 13, 15, 16, Tellinites gibbosa var. kayseri Beushausen (p. 165). 

Figure 4, Nuculoidea bellatula sp. nov. (p. 174). 

Figure 5, Tellinites chapmani sp. nov. (p.163). 

Figure 6, Nuculoidea cordata sp. nov. (p. 175). 

Figure 7, cf. Nuculoidea aquisgranensis Beushausen (p. 176). 

Figure 8, Nuculoideatrigonale sp. nov. (p. 176). · 

Figures 10, 12, 19, Paleoneilo (Ditichia) mainensis Clarke (p. 168). 

Figures 14, 17, Glossites barrandii sp. nov. (p. 144). 

Figlire 18, Goniophora kayseri sp. nov. (p. 230). 

Figure 20, Glossites amnigenoides sp. nov. (p. 145). 

Figure 21, Leiopteria reisiana sp. nov. (p. 211). 

Figures 22, 26, Myalina maureriana sp. nov. (p. 213). 

Figure 23, llfegambonia cardiiformis var. parviuscula var. nov. (p. 201). 

Figures24, 27, llfyalina maureriana var. pterin;eoides var. nov. (p. 215). 

Figure 25, cf. Cypricardella rotundata sp. nov. (p. 246). 

Figure 28, Myali7J,a maureriana var. lata var. nov. (p. 215). 

1. Cleidophorus curtus sp. nov. Mold of interior of left valve, showing the strong ridge on interior separating anterior 

muscular scar from umbone, and slight ridge on posterior side. Chapman sandstone, Edmunds Hill, Chapman 

Township, Aroostook County, Maine. 

2. Orthodesma carinijera sp. nov. Interior mold of a left valve, the supposed outline of the posterior and front margin 

is expressed by added line. Chapman sandstone, 2 miles west of Presque Isle Stream, Chapman Township, 

Aroostook County, Maine. 

3. Tellinites gibbosa var. kayseri Beushausen. Mold of interior of a small left valve, in which the anterior and front 

are preserved, but the beak and hinge portion are absent. Chapman sandstone, same locality as figure 2. 

4. Nuculoidea bellatula sp. nov. Exterior of a right valve, showing .the narrow erect form and surface markings. 

X 1!. Chapman sandstone, west side of Edmunds Hill, Chapman Township, Aroostook County, Maine. 

5. Tellinites chapmani sp. nov. Mold of inte_rior of right valve, near the upper posterior margin of which a part of 

the shell is preberved, ·showing the surface lineation. The coarser concentric undulations seen on the body of 

the shell evidently belong to the inner surface of the shell and are not expressed on the exterior. Chapman 

sand~tone, same locality as figure 2. · 

6. Nuculoidea cordata sp. nov. Exterior of a right valve, showing size, form, and surface markings. Chapman sandstone, same locality as figure 1. 

7. cf. Nuculoidea aquisgranensis Beushausen. An imperfect specin:ten showing the left valve without the umbonal 

portion. Tl;le form of the body of the shell, surface markings, pallial line, and anterior muscular scar are seen 

in the figure. Chapman sandstone, same locality as figure 4. 

8. Nuculoidea trigonale sp. nov. A small right valv.e, showing the thick umbonal portion of the shell and wellrounded front, with a single strong growth lamella. X 1~. Chapman sandstone, same locality as figure 4. 

9. Tellinites gibbosa var. kayseri Beushausen. Mold of interior of a small left valve, showing the concentric folds 

and the faint radiating lineation, which do not appear on the outer surface of the shell. Chapman sandstone, 

same locality as figure 2. · 

10. Paleoneilo (Ditichia) mainensis Clarke. Interior mold of left valve, showing the strong ridge on the inner side of 

both the anterior and posterior muscular scars and a low umbonal fold from beak to front on inner side of the 

internal ridge. The hinge margin is lacking. Chapman sandstone, same locality as figure 2. 

11. Tellinites gibbosa var. kayseri Beushausen. Mold of interior of left valve, showing almost complete outline of the· 

shell and the characteristic undulations on the posterior slope and mdial lines over the body of the shell on 

the interior surface. Chapman sands~one, same locality as figure 2. 

12. Paleoneilo (Ditichia) mainensis Clarke. Interior mold of right valve, showing the strong ridges inside the muscular scars, the anterior much deeper and broader than the posterior, indication of two of the cardinal teeth in 

front of the beak, and the slight undulations along the posterior slope. Chapman sandstone, same locality as 

figure 2. 

13. Tellinites gibbosa var. kayseri Beushausen. A specimen showing the form of the beak and front end of a left valve. 

Chapman sandstone, same locality as figure 2. 

14, 17. Glossites barrandii sp. nov. Mold of exterior and matrix of same specimen showing the form and surface markings of a left valve. Chapman sandstone, same locality as figure 4. 

326 ' 
U S. GEOLOGICAL SURVEY PROFESSIONAL PAPER 89 PLATE XIX 

l 2 

7 

3 4 5 8 

9 

10 11 

12 

13 

14 

15 16 

22 

26 27 
FAUNA OF THE CHAPMAN SANDSTONE OF MAINE. 

' 

327 

15. 1'ellinites gibbosa var. kayseri Beu.shausen. A right valve, pa.rtly a mold of interior but showing on the front and 

ru1terior the outer surface with fine sharp concentric lines. The posterior slope is crushed, so that evidence of 

the undulations is destroyed. Chapman sandstone, same locality as figure 2. 

16. Tellinites gibbosa var. kayseri Beushausen. Mold of interior of right ,valve, showing strong surface undulations on 

posterior slope, faint radiating lines over the body of the shell and distinct concentric lines of growth over the 

whole~ Chapman sandstone, same locality as figure 2. 

17. See figure 14. 

18. Goniophora kayseri sp. nov. A sandstone mold of a left valve, showing form, but devoid of either internal or 

external markings. Chapman sa.ndstone, same locality as figure 4. 

19. Paleoneilo (Ditichia) rnainens·is Clarke. An imperfect sandstone mold of a left valve. Chapman sandstone, same 

locality as figure l. 

20. Glossites arnnigenoides sp. nov. A right valve, the umbonal and cardinal part absent and theoretically reproduced 

by lines. Shows the surface markings and the anterior muscular scar. Chapman sandstone, same locality aa 

figure l. 

21. Leiopteria reisiana sp. nov. Exterior of a left valve showing concentric surface sculpture and the form and outline 

of the shell. Chapman sandstone, Presque Isle Stream, Chapman Township, Aroostook County, Maine. 

22. :Afyalina rnaureriana sp. nov. A small specimen, mainly an interior mold, of a left valve. Chapman sandstone, 

same locality as figure 21. 

23. Megambonia cf. M.cardiiforrnis var. parviuscula var. nov. Specimen showing the exterior form and markings of 

a loft valve. Moose River sandstone, Detroit, Somerset County, Maine. 

24. :Afyalina rnaureriana var. pterinreoides (Clarke). Interior mold of left valve, showing pallial line and (faintly) the 

posterior scar. Chapman sandstone, same locality as figure 21. 

25. cf. Cljpricardella rotundata sp. nov. A sandstone mold of a left valve, showing very little upon which to identify 

it, but referred with doubt to the species named. Chapman sandstone, same locality as figure 1. (See also 

Pl. XXI, figs. 14, 15.) 

26. :Myalina rnaureriana sp. nov. Internal mold of left valve, showing distinctly the two muscular scars and the pallial 

margin. Chapman sandstone, same locality as figure 21. . · 

27. :Afyalina rnaureriana var. pterinmoides (Clarke). Mold of a nearly perfect left valve, showing shell over right side 

of body and internal mold on left. Chapman sandstone, same locality as figure 21. 

28. :Afyalina rnaureriana var. lata var. nov. Mold of interior of left valve, showing pallial line and the posterior muscular 

scar; the anterior scar not -yisible. Chapman sandstone, same locality as figure 21. . (See also :£>1. XVIII, figs. 

7, 9, 10, 12.) 
PLATE XX. 

the figures on this plate are of natural size.) 

Figures 1-7, Modiomorpha.chapmanisp. nov. {p. 221). 

Figure 8, Grammysia (Grammysioidea) princiana sp. nov. (p. 136). 

Figure9, Schizodusf prunum sp'. nov. (p. 238). 

1. Modiomorpha chapmani sp. nov. Sandstone mold of a right valve. The s4ell substance is entirely removed and 

the concentric lineation, though it represents the surface markings, is probably less sharp than on the actual 

surface of the shell. Chapman sandstone, Edmunds Hill, Chapman Township, Aroostook County, Maine. 

2 .. Modiomorpha chapmani sp. nov. A somewhat weathered mold of a left valve on which the concentric markings 

are nearly obliterated. Chapman sandstone, westside of Edmunds Hill, Chapman Township, Aroostook County, 

Maine. 

3. Modiomorpha chapmani sp. nov. Mold of right valve on which the concentric lines on the posterior slope of the 

cardinal border of the shell and the coarser surface folding on the anterior end are distinctly preserved. Chapman sandstone, same locality as :figure 2. · 

4. Modiomorpha chapmani sp. nov. A left valve in which the margin is lacking except at the posterior end, but the 

body form is represented. Chapman sandstone, same locality as figure 1. 

5. Modiomorpha chapmani sp. nov. An imperfect left valve, the outlines of which are reconstructed. Chapman 

sandstone, same locality as figure 2. 

6. Modiomorpha chapmani sp. nov. Stone mold of a·left valve, much weathered, but still preserving the strong concentric growth llnes of the shell. Chapman sandstone, same locality as figure 1. 

7. Modiomorpha chapmani sp. nov. Posterior part of a left valve showing the broad sulcus on the median part of the 

shell. Chapman sandstone, same locality as :figure 2. 

8. ·Grammysia (Grammysioidea) princiana.sp. nov. Mold of th-e exterior of a large right valve, the surface considerably 

weathered but still showing the concentric growth varices, the posterior umbonal angular ridge, and the posterior 

muscular scar. Moose River sandstone, Detroit, Somerset County, Maine. 

9. Schizodus? prunum sp. nov. An imperfect stone mold, showing llttle of definite value but resembling in form the 

genus .Schizodus. Chapman sandstone, Edmunds Hill, Chap~an Township, Aroostook County, Maine. 

328 
U. S. GEOLOGICAL SURVEY PROFESSIONAL PAPER 89 PLATE XX 

1 

2 

3 

4 

5 

6 

7 

9 

8 
U. S. GEOLOGICAL SURVEY PROFESSIONAL PAPER 89 PLATE XXI 

14 

15 16 
PLATE XXI. 

(All the figures on .thiS plate are of natural s~e except figure 1, which is magnified 2 diameters.] 

Figure 1, Oypricardella bellatula sp. nov. (p. 244). 

Figures 2-7, 10-13, },fodiomorpha aroostooki sp. nov. (p. 219). 

Figure 8, Cypricardella transversa sp. nov. (p. 247). 

Figure 9, Cypricardella cf. C. bicostula Krantz (p. 248). 

Figures 14-15, Cypricardella rotundata sp. nov. (p. 246). 

Figure 16, Modiomorpha cf. },f. protea Clarke (p. 219). 

1. Cypr·icardella bellatula sp. nov. A well-preserved mold of this small species, showing well the form and surface 

characters X 2. Chapman sandstone, Presque Isle Stream, at end of Tweedy road, Chapman Township, 

Aroostook County, Maine. ·· 

2. :Afodiomorpha aroostooki sp. nov. Exterior of right valve, somewhat worn, the edges imperfect, but showing 

the form and surface markings. Chapman sandstone, Presque Isle Stream, Chapman Township, Aroostook 

County, Maine. 

3. Alodiomorpha aroostooki sp. nov. Ventral part of left valve, showing the concentric li:q.eation of the surface. 

Chapman sandstone, same locality as figure 2. · 

4. Modiomorpha aroostooki sp. nov. Another imperfect left valve, in which the form ·is more elongate in the 

direction of the umbonal ridge. Chapman sandstone, same locality as figure 2. 

5 . . Mocl-iomorpha aroostooki sp. nov. Fragment of a right valve, showing a piece of the shell and the mold of the 

interior, the pallial margin, and the inner edge of the posterior muscular scar. Chapman sandstone, same 

locality as figure 2. 

6. lllodiomorpha aroostooki sp. nov. Weathered fragment of left valve. Chapman sandstone, same locality as 

figure 2. 

7. Alodionwrpha aroostooki sp. nov. A nearly complete left valve, showing the form and surface markings. 

Chapman sandstone, same locality as figure 2. 

8. Cypricardf'lla transversa sp. nov. A sandstone mold showing form but very little of surface character, referred 

with doubt to the genus Cypricardella. Chapman sandstone, Edmunds Hill, Chapman Township, Aroostook 

County, Maine. · · 

9. Cypricardella cf. C. bicostula Krantz. A finely preserved fragment of the m9ld of· the exterior of a left valve. The 

specimen is concave. Chapman sandstone, same locality as figure 8. 

10. Modiomorpha aroostooki· sp. nov. Mold of interior of left valve, showing the anterior muscular scar. Chapman sandstone, same locality as figure 2. 

11. Modiomorpha aroostooki sp. nov. Mold of interior of left valve, showing umbonal ridge and anterior muacular 

scar. Chapman sandstone, same locality as figure 2. 0 

• • 

12. :Afodiomorpha aroostoolci sp. nov. Mold of interior of left valve, somewhat crushed, showing anterior and 

posterior(?) muscular scars. Chapman sandstone, same locality as figure 2. 

13. Modiomorpha aroostooki sp. nov. A left valve in which the surface of the· front part and the form of the umbo 

and umbonal ridge are well preserved. Chapman sandstone, same locality as figure 2. 

14-15. Cypricardella rotundata sp. nov. Stone molds of left valves; weathered specimens; the surface markings being 

removed. Chapman sandstone, west side of Edmunds Hill, Chapman Township, Aroostook County, Maine. 

16. Modiomorpha protea Clarke. ·Fragment of left valve, showing the form of Clarke's. species; Chapman sandstone. same locality as figure 8. · 

329 
PLATE· XXII. 

[All the figures on this plate are of natural size.) 

Figures 1, 3, Phacopidella chapmani sp. nov. (p. 287). 

Figures 2, 4, 7, 9, Polypora lilrea Hall (p. 20). 

Figure 5, Dalmanites (Synphoria?) sp. p (p. 289). 

Figur~ 6, Polypora psyche Billings (p. 20). 

Figure 8, Dalmanites (Synphoria?) sp. o: (p. 288). 

Figures 10, 12, 13, 15, 21, Homalonotus vanuxemi Hall (p. 286). 

Figures 11, 14, 17, 18, 22, Homalonotuslaticaudatus sp. nov. (p. )285. 

Figure 16, Favosites sp. indet. (p. 14). 

Figure 19, Asterolepis clarkei Eastman (p. 293). 

Figure 20, Trachyderma ( 1Gyrichnites) speciosa sp. nov. (p. 19). 

1. Phacopidella chapmani sp. nov. Cephal on, showing small size, elongate glabella, with only the third pair of furrows 

showing. Chapman sandstone, west side of Edmunds Hill, Chapman Tom:t.Bhip, Aroostook County, Maine. 

2, 4, 7, 9, Polypora lil::.ea Hall. Stone molds of incomplete fronds; showing the arrangement and size of the fenestrules. 

Chapman sandstone, same locality as figure 1. 

3. Phacopidella chapmani. sp. nov. Fragment of a small pygidium, showing resemblance to Proetus and Phacop~. 

Chapman sandstone, same locality as figure l. 

4. See fi~tre 2. 

5. Dalmanites (Synphoria?) sp. [3. Fragment of a pygidium of a small specimen, too imperfect for satisfactory 

specific definition. Chapman sandstone, same locality as figure 1. 

6. Polypora psyche Billings. Stone mold of incomplete frond, showing fenestrules of larger size than in P. lilrea. 

Chapman sandstone, same locality as figure 2. 

7. See figure 2. 

8. Dalmanites (Synphoria?) sp. a. Fragment of a pygidium, too imperfect for satisfactory specific definition. Chapman sandstone, Edmunds Hill, Chapman Plantation, Aroostook County, Maine. 

9. See figure 2. 

10. Homalonotus vanuxemi Hall. A small terminal part of a pygidium. Chapman sandstone, 2 miles west of Presque 

Isle Stream, 'Chapman Township, Aroostook County,"Maine. 

11. Homalonotus laticaudatus sp. nov. A small, nearly complete glabella, showing the eye lobes and occipital ring. 

Chapmari sandstone, same locality as figure 8. 

12. Homalonotus vanuxemi Hall. Portion of the right side of a glabella, showing part of the right eye lobe. Chapman sandstone, same locality as figure 10. 

13. Homalonotus vanuxemi Hall. A nearly complete pygidium of a· small specimen. Chapman sandstone, same 

locality as figure 10. 

14. Homalonotuslaticaudatus sp. nov. Posterior of a mediu:rn-sized pygidium, showing the wide axis and broad form. 

Compare with figure 13. Chapman sandstone, same locality as figure l. 

15. Homalonotus vanuxemi Hall. A hypostoma preserving a portion of the shell substance. Chapman sandstone, 

same locality as figure 10. 

16. Favosites ~P· indet. Mold of surface of mass of coral, showing ~he filling of the mouths of the coralites. Chapman 

sandstone, same locality as figure l. 

17. Homalonotus laticaudatus sp. nov. A fragment of a large pygidium. Chapman sandstone, same locality as figure l. · . · 

18. Homalonotuslatica-q,datus sp. nov. Stone mold of a fragment of a large pygidium, showing the broad axis. Chapman sandstone, same locality as figure 8. 

19. AISte1'0lepsis clarkei Eastman. A dorso-median plate, showi~g the closely crowded stellate tubercles and the anglilar 

median ridge, with rapidly sloping sides characteristic of the genus. Chapman sandstone, 2 miles west of 

Presque Isle Stream, Chapman Township, Aroostook County, Maine. 

20. Trachyderma (?Gyrichni'tes) speciosa sp. nov. A piece of the tubular skin molded in the sandstone block, showing 

the shape of the flattened tubular form and the broad wrinkles of the surface. Chapman sandstone, same locality 

as figure 8. 

21. Homa~onotus v(muxemi Hall. A fragment of the right free cheek. Chapman sandstone, same locality as figure 10. 

22. Homalonotuslaticaudatus sp. nov. Mold of !1 segment of the thorax. Chapman sandstone, same locality as figure 1. 

330 
U. S. GEOLOGICAL SURVEY PROFESSIONAL PAPER 89 PLATE XXII 

1 2 3 

4 5 

6 7 

8 9 10 

11 12 13 14 

16 

15 

19 17 

18 

20 

21 22 
U. S. GEOL OGICAL SURVEY PROFESSIONAL PAPER 89 PLATE XX III 

1 

:2 

4 

5 

6 

7 8 

~~-, . . 

9 

11 

15 

13 

14 

16 17 
PLATE XXIII. 

(All tho figures on this plate are of natural size except figure 10, which is magnified 2 diameters.] 

Figure 1, ??Conocardium dubia sp. nov. (p. 201). 

:Figure 2, Actlnoptorella sp. (] (p.-192). 

Flgur cs 3, 7, Actlnopterella sp. r (p. 192). 

Figures 4, 10, Limoptera pauciradiata Hull var. chapmani var. nov. (p. 204). 

Figure 5, Pteronitella quadrata sp. nov. (p. 196). 

Figures 6, 8, 9, 11-13, Actinopterella radialis (Cl.arke) (p; 184). 

Figures 14, 15, Cypricardites detroitense sp. nov. (p. 155). 

FJguros 16,17, Grammysia modiomorphre Clarke (p. 138). 

1. ??Conocardium dubia sp. nov. This fragment is supposed to represent the inflated middle portion of a right 

valve of a Conocardium, showing the longitudinal furrows over the body part of the shell. Chapman sandstone, 

Presque Isle Stream, Chapman Township, Aroostook County, Mai.ne. 

2. Actinopterella sp. a. Left valve, with imperfect surface. The figure does not exhibit the highly arched form of 

the shell which is characteristic of the original. Chapman sandstone, 2! miles west of Presque Isle Stream, 

Chapman Township, Aroostook County, Maine. 

3. Actinopterella sp. r. Fragment of a left valve ehowing in mold the exterior markings. Chapman sandstone, 

Presque Isle Stream, at end of Tweedy road, Chapman Township, Aroostook County, Maine. 

4, 10. Limoptera pauciradiata Hall var. chapmani var. nov. Molds of the interior and exterior of a single left valve. 

In figure 4 the outline is somewhat distorted by crushing, but the relation of body and wing is well seen; in figure 

10 (which is enlarged 2 diameters) the nature of the surface sculpture is seen. Chapman sandstone, Edmunds 

Hill, Chapman Township, Aroostook County, Maine . 

.5. Pteronitella quadrata sp. nov. Stone mold of the left valve, of which the contour, wing, and surface markings are 

exhibited. Chapman· &'l.ndstono, same locality as figure 1. 

·6. Actinopterella radialis (Clarke). Mold of interior of left valve, showing the posterior cardinal tooth and the anterior 

cardinal of this valve with cavity for articulation with its opposite tooth. Chapman sandstone, same locality 

as figure 1. 

7. Actinopterella sp. r. Mold of interior of left valve, showing the narrow, highly arched body of the shell. Chapman 

sandstone, same locality as figure 3. 

8. Actinopterella radialis (Clarke). Fragment of mold of exterior of left valve, showing part of the anterior wing 

and tho surface sculpture. Chapman sandstone, same locality as figure 1. 

9. Actinopterella radialis (Clarke). Mold of interior of left valve, showing wing and posterior tooth: Chapman sandstone, same locality as figure 1. 

10. See figure 4. 

:11. Actinopterello radialis (Clarke). Interior mold of a left valve, the beak of which is abruptly cut off, showing the 

striated hinge area and the posterior hinge tooth. Chapman sandstone, same locality as figure 1. 

12. Actinopterella radialis (Clarke). Direct view of mold of right valve, sho"wing the anterior teeth and the overarching beak of the left valve. Chapman sandstone, same locality as figure 1. 

13. Actinopterella radialis (Clarke). Mold of interior of another right valve of more regular form than the specimen 

shown in figure 12. Chapman sandstone, same locality as figure 1. 

'14. Cypricardites detroitense sp. nov. Mold of interior of two valves still joined at the hinge ·line. The left valve, 

showing hinge teeth, is in its natural form, but tho right valve is crushed. Moose River sandstone, Detroit, 

Somerset County, Maine. 

15. Cypricardites. detroitense sp. nov. 1\lold of interior of right valve, showing the form and exhibiting the posterior 

hinge teeth. Moose River sandstone, same locality as figure·l4. 

16. Grammysia modiomorphre Clarke. A worn, imperfect specimen of a right valve,. showing the anterior end and 

oblique sulcus across center of shell. Chapman sandstone, same locality as figure 4. 

:17. Grammysia modiomorphre Clarke. A worn specimen, showing faintly the concentric varices and the general form 

of a right valve. Chapman sandstone, same locality as figure 4. 

331 
PLATE XXIV. 

[All the figures on this plate are of natural size except figs. 1, 2, 3, 5, and 7, which are magnified 2 diameters.] 

Figures 1, 3, 5, 7, Paleosolen chapmani sp. nov. (p. 251). 

Figure 2, Pleurodictyum problematicum Goldfuss (p. 14). 

Figure 4, Megambonia cf. M. cardiiformis Hall (p. 199). 

Figure 6, cf. Edmondia (sp. indet.). 

Figure 8, cf .. Schizodus (sp. indet.) (p. 239). 

Figure 9, Sphenotomorpha rigidula sp. nov. (p. 234). 

Figure 10, Grammysioidea ellymelloides sp. nov. (p. 138). 

Figure 11, Elymella harrisi sp. nov. (p. 142). 

Figure 12, Grammysia acadica.Billings var. (p. 135). 

Figures 13, 15, Goniophora omega sp. nov. (p. 232). 

Figure 141 Anodontopsis maccoyiana sp. nov. (p. 236). 

Figure 16, Cimitaria cf. C. chapmani sp. nov. (p. 255). 

1. Paleosolen chapmani sp. nov. A nearly complete right valve, showing the general form and outline. X 2. Chapman sandstone, Presque Isle Stream, at end of Tweedy road, Chapman Township, Aroostook County, Maine. 

2. Pleurodictyum problematicum Goldfuss. A specimen showing mold of the interior of the tubules, too poorly preserved for close specific identification. Chapman sandstone, same locality as figure 1. . 

3. Paleosolen chapmani ·sp. nov. A nearly complete 'right valve, more slender that the one shown· in figure 1 and 

exhibiting the siphonal plication of the posterior part of the shell. X 2. Chapman sandstone, same locality 

as figure 1. 

4. Megambonia cf. M. cardiijorrnis Hall. An imperfect left valve, which in surface markings and. fqrm presents. 

the characters of Hall's species but is smaller. Moose River sandstone, Detroit, Somerset County, Maine. 

5. Paleosolen chapmani sp. nov. Left valve, showing the anterior end, umbo, surface markings, and siphonal plicationa. X 2. Chapman sandstone, same locality as figure 1. 

6. cf. Edmondia (sp. indet.). Stone mold of right valv-e, showing the general form and size but no marked specific· 

characters. Chapman sandstone, Edmunds Hill, Aroostook County, Maine. 

7. Paleosolen chapmap,i sp. nov.· A small right valve, showing the characters of the posterior half of the shell. X 2. 

Chapman sandstone, same locality as figure 1. 

8. cf. Schizodus (sp. indet.). An imperfect stone mold, showing the general form and size but nothing to determine accurately the specific characters. Chapman sandstone, west side of Edmunds Hill, Aroostook County, 

Maine. · 

9. Sphenotomorpha rigidula sp. nov. An imperfect right valve, showing form and surface markings. Chapman. 

sandstone, 2! miles west of Presque Isle Stream, Chapman Township, Aroostook County, Maine. 

10. Grammysioidea ellymelloides sp. nov. A crushed and otherwise imperfect· right valve, showing the general form.· 

of the shell. Chapman sandstone, same locality as figur-e 1. 

11. Elymella harrisi sp. nov. A nearly complete left valve, showing form and surface markings. Chapman sandstone, same locality as figure 6. 

12. Grammysia acadica Billlngs var. An imperfect stone mold of a left valve referred to as a variety of Billings's· 

species. Chapman sandstone, same locality as figure 6. 

13, 15. Goniophora omega sp. nov. Two specimens representing the left and right valves, upon which the outline, 

the surface form, and (indistinctly) the markings can be seen. Chapman sandstone, 2 miles west of Presque· 

Isle Stream, Chapman Township, Aroostook County, Maine. 

14. Anodontopsis maccoyiana sp. nov. Mold of interior of left valve, showing the hinge teeth and the flattened margin 

which may mark the limits of the pallial margin. · Chapma~ sandstone, same locality as figure 9. 

15. See figure 13. 

16. Cimitaria cf. C. chapmani sp. nov. A small specimen, showing the exterior of a left valve. The very abrupt fall 

from umbonal ridge to the posterior slope of the sheil, which is nearly flat, is not well brought out by this figure;. 

the sharp edge of the ridge is shown. Chapman sandstone, same locality as figure 1. 

332 
U. S. GEOLOGICAL SURVEY PROFESSIONAL PAPER 89 PLATE XXIV 

2 

4 

6 7 

8 

11 9 

10 

14 

13 15 

16 

12 5 
U. S. GEOLOGICAL SUR VEY PROFESSIONAL PAPER 89 PLATE XXV 

1 2 3 

4 

5 

6 7 8 

9 10 12 

11 

13 15 

14 16 

20 23 19 23a 24 

17 18 

26 

27 21 
PLATE L~V. 

[All the figures on this plate are of natural size except figures 17 and 18, which are enlarged 2 diameters.) 

FJguros 1, 3-5, 12, Tellinites gibbosa var. kayseri Beushausen (p. 165). 

FJgmcs 2, 10, Cleidophorus perovalis sp. nov. (p. 161). 

]!'igmcs 6, 0, 11, 13, Paleoneilo (Ditichia) mainensis Clarke (p. 168). 

]!'Jguro 7, ltfyoplusia chapmani sp. nov. (p. 162). 

FJguro 8, Tellinites gibbosa var. crassa Beushausen (p. 165). 

FJguro 14, Tellinites curta sp. nov. (p. 165). 

]!'Jgurcs 111, 10, Leda harrisi sp. nov. (p. 171). 

]?Jgurcs 16, 20, Paleoneilo (Ditichia) mainensis var. umbonata var. nov. (p. 170). 

FJgurcs 17, 18, ~ctinoptcrclla sp. p (p. 192). 

J?Jgurcs 21, 22, 25, 26, Preavicula oblonga Hall (p. 207). 

]?Jgurcs 23, 23a, 24, Paracyclas bulloides sp. nov. (p. 258). 

FJguro 27, Beachia chapmani sp. nov. (p. 71). 

l.. 1'ellinites gibbosus var. ka.yseri Beushausen. A mature elongate left valve, showing the umbonal ridge and sulci 

strongly developed, also along the posterior hinge the hinge teeth. Chapman sandstone, Presque Isle Stream, 

at end of Tweedy 1·oad, Aroostook County, Ma'tne. 

2. Cleidoplwrus perovalis sp. nov. An incomplete mold of interior of left valve, showing the clavicular ridge in front 

of the umbo. Chapman sandstone, west side of Edmunds Hill, Chapman Township, Aroostook County, Maine. 

3. Tellinites gibbosus var. kayseri Beushausen. A short young shell, showing right valve, the posterior end wanting. 

Chapman sandstone, same locality as figure 1. 

4. Tellinites gibbosus var. ka.yseri Beushausen. A mature elongate right valve, showing outlines and surface form. 

Chapman sandstone, same locality as figure 1. 

5. Tellinites gibbosus var. ka.yseri Beushausen. A small short left valve, showing teeth on hinge margin. Chapman 

sandstone, same locality as figure 1. 

6, ll. Paleoneilo (Ditichia.) rnainensis Clarke. A narrow and a broad form of the right valve, showing the anterior 

ridge. Chapman sandstone, same locality as figure 1. 

7. Jfyopl·usia cha.prnani sp. nov. An imperfect left valve, showing the general outline and the form of the anterior 

half of the shell. Chapman sandstone, same locality as figure 1. 

8. Tellinites gibbostts var. crassa Beushausen. An extremely short, small right valve. Chapman sandstone, same 

locality as figure l. 

9, 13. P.aleoneilo (Ditichia) rnainensis Clarke. Two specimens showing different outlines. The anterior ridge is 

evident in figme 9 but not in figure 13. These specimens and those repr~sented in figures 6 and 11 show 

extremes of expressions of this variable form. Chapman sandstone, same locality as figure 1. 

10. Cleidophonts perovalis sp. nov. Right valve, showing clavicular ridge, gently curving stirface, and the nearly. 

complete outline of the species. Chapman sandstone, same locality as figure 2. 

11. See figure 6. 

12. Tell'inites gibbostts var. kayseri Beushausen. A short left valve. Compare with figure 1. Chapman sandstone, 

same locality as figure 1. 

13. See figure 9. 

14. 1'ellinites eurta sp. nov. Right valve showing the broad, even arching of the body of the shell, the slight, narrow 

umbonal furrows, and on the anterior front a portion of the surface of the shell. Chapman sandstone, same 

· locality as figure 2. 

15, 19. Leda hanisi sp. nov. Two right valves, showing the form and size but not the surface characters. ·Chapman 

sandstone, 2 miles west of Presque. Isle Stream, Chapman Township, Aroostook County, Maine. 

Hi, 20. Paleoneilo mainensis var. umbonata var. nov. Two left valves, showing the produced narrow umbones, the 

decided ~ulcus inside the umbonal ridge, and the anterior ridge; also the extremes of long and short type of shell · 

observed in the series of specimens of the typical species. Chapman sandstone, same locality as figure 1. 

17, 18. Actinopterelht sp. [3. Two imperfect left valves, showing the short quadrate form, the large wing and ear, and 

the radiating ltnes over the body and slightly exhibited on the posterior wing, apparently lacking on the 

anterior car. X 2. Chapman sandstone,_ same locality as figure 1. . 

19. See figure 15. 

\ 20. See figure 16. 

21, 22, 25. P1'cavicula oblonga Hall. Partly exfoliated left valves, showing the form, partly restored qutlines, and 

faint radiating plication, which may pertain to the interior rather than exterior of the shell. Chapman sandstone, 2~ miles west of Presque Isle Stream, Chapman Township, Aroostook County, Maine. 

23, 23a, 24. Paracyclas bulloides sp. nov. Three interior molds of left valves. The anterior muscular scar and pallial 

line are best seen in figure 23, and the form and particularly the posterior slope are best exhibited by figure 24. 

Chapman sandstona, same locality as figure 15. 

25. See figure 21. 

2(). P1·eavicu.la oblonga Hall. Right valve, showing the pallial line and scar of the posterior muscuhir impression. 

Chapman sandstone, same locality as figure 21. 

27. BeacMa cltaprnani sp. nov. Stone cast referred with doubt to this species. Chapman sandstone, Edmunds Hill, 

Chapman 'l'ownsh.ip, Aroostook County, Maine. 

333 
PLATE XXVI. 

[All the figures on this plate are of natural size except figure 1, which is magnified 4 diameters.] 

Figure 1, Leda minuta sp. nov. (p. 172). 

Figures 2, 3, 5-7, 10, 12, 13, A nodontopsis maccoyiana sp. nov. (p. 236). 

Figure 4, Physetomya sp. indet. (p. 140). 

Figures 8, 9, Preavicula brevis sp. nov. (p. 208). 

Figures 11, 15, 16, Preavtcula oblonga (Hall) sp. et gen. nov. (p. 207). 

Figure 14, Modiomorpha cf. M. protea Clarke (p. 219). 

1. Leda miriuta sp·. nov. A minute right vahe, showing the form of the type specimen. X 4. Chapman sandstone, PJ;"esq1,1e Isle Stream, at end of Tweedy road, Chapman Township, Aroostook County, Maine. 

2, 3. Anodontopsi's maccoyiana sp. nov. Two small left valves, showing the form and imperfectly the exterior characters of the shell. Chapmansandstone,· 2 miles. west of Presque Isle Stream, Chapman Township, Aroostook 

County, Maine. 

4. Physetomya sp. indet. An imperfect left valve, showing the surface wrinkles and outline. Chapman sandstone, 

Edmunds Hill, Chapman Township, Aroostook County, Maine. 

5-7, 10. Anodontopsis maccoyiana sp. nov. Four medium-sized right valves, partly exfoliated, showing slight differences in outline. Chapman sandstone, same locality as figure 2. 

8. Preavicula brevis sp. nov. A f>artly exfoliated specimen, showing the narrow, elongate form and the concentric 

lines of growth. Chapman sandstone, same locality as figure 2. 

9. Preavicula brevis sp. nov. A larger specimen with more expanded front and no concentric lines evident on the 

surface. The two shells shown in figures 8 and 9, though differing in present appearance, are believed to represent a single species, as they come from the same locality. The illustrations exaggerate the differences; figure 9 

gives the typical form. Chapman sandstone, same locality as figure 2. 

10. See figure 5. 

11, 16. Preavicula oblonga Hall. Two specimens of right valves showing the ordinary characters of the species. (See 

also Pl. XXV, figs. 21, 22, 25, 26.) Chapman sandstone, same locality as figure 2. · 

12, 13. Anodontopsis maccoyiana, o3p. nov. Two large right valves, partly exfoliated, showing well the surface ~arkings over posterior hinge in figure 12, and the pallial line and muscular scars in both figures. Chapman sandstone, same locality as figure 2. 

14. Modiomorpha cf. M. protea Clarke. An imperfect left valve resembling in general form the :first of the specimens figured by Clarke under the name M:protea. (See also Pl. XXI, fig. 16.) Chapman sandstone, same 

locality as figure 4. 

15. Preavicula oblonga Hall. ·Mold of the interior of a large incomplete right valve, in which a ridge from the 

anterior muscular scar toward the front is particularly conspicuous; a wide.furrow separates this ridge from the 

body of the shell. Referred with doubt to this species. Chapman sandstone, same locality as figure 4. 

334 
U. S. GEOLOGICAL SURVEY PROFESSIONAL PAPER 89 PLATE XXVI 

1 2 3 4 

5 6 

7 

10 

8 9 

12 13 

11 

14 16 

15 
U. S. GEOLOGICAL SURVEY PROFESSIONAL PAPER 89 PLATE XXVII 

3 

4 5 

14 

8 9 

10 

15 

16 

18 19 
PLATE XXVII. 

fUn loss othorwiso stated all tl1e figures on this plate are magnified 10 diameters. All the specimen's were procured from the Chapman sandstone.) 

Figuros, 1-6, Zygobeyrichia devonica Jonos and Woodward (p. 291). 

J?iguros 7-10, Zygobeyrichia O..'Ctrema Ulrich (p. 292). 

Figures 11-16, Zygobeyrichia apicalis Ulrich (p. 292). 

Figures 17-19, Ctenobolbina (?) cornuta Ulrich (p. 289). 

l. Zygobeyrichia devonica. Jones and Woodward. Cast of the interior of a right valve tilted so as to obscure the central 

part of the ventral edge and cause the swollen upper end of the median lobe to appear as farther removed from the 

dorsal edge than in a view taken at a right angle to the plane of the edges of the valve. U. S. Nat. Mus. Cat. 

No. 61359. 

2. Zygobeyrich?:a dcvonic.a Jones and Woodward. View taken from a clay squeeze of a natural mold of a left valve, X 11. 

'l'he .flattened border is more sharply defined than usual. U. S. Nat. 1\f.us. Cat. No. 61360. 

3. Zygobmjrichia devonica Jones and Woodward. Drawing of a cast of the interior of a large left valve, X 11, with an 

outline sketch indicating relief of surface in a view of the posterior end. U. S. Nat. Mus. Cat. No. 61380. 

4. Zygobeyrichia devonica Jones and Woodward. Cast of the interior of a left valve of the female form of the species, 

showing the position and elongate form of the ventral pouch. U. S. Nat. Mus. ·cat. No. 61381. 

5. Zygobey·n:cMa de·vonica Jones and Woodward. Cast of the interior of a left valve, 'showing differences in the outline 

and in the posterior lobe thought to he clue chiefly to distortion subsequent to burial. U.S. Nat. Mus. Cat. No. 

61382. 

6. Zygobmjrichia devonica Jones and Wooclward. Another slightly distorted cast of the interior of a left valve. U. S. 

Nat. Mus. Cat. No. 61383. 

7. Zygobeyn:chia extrema illrich. · Cast of the interior of the right.valve of a female example of this species, the ventral 

pouch and median lobe slightly crushed by rock pressure. U. S. Nat. Mus. Cat. No. 61363. 

8, 9. ZygobmJrichia cxt·rmna Ulrich. Cru;t of the interior of a left valve and view of anterior end of same. U.S. Nat. 

Mus .. Cat. No. 61376. 

10. Zygobeyrichia etct1·mna Ulrich. Cast of the interior of a right valve. U. S. Nat Mus. Cat. No. 61377. 

11: 1:!. Zygobey1-ichia apicali.c; Ulrich. Casts of the interior of two right valves, showing small differences in outline, 

probably caused by distortion. 'l'he smaller specimen (fig. 12) is believed to be the more normal in form. U. S. 

Nat. Mus. Cat. Nos. 61361, 61384. 

13, 14. Zygobmjrichia apicalis Ulrich. 'l'estiierous left valve of the female form, as seen in side and ventral views. 

:Figure 13 shows the pitted ornament on the ventral pouch and adjacent parts of the broad anterior lobe. U. S. 

Nat. Mus. Cat. Nos. 61362, 61385. 

15, 16. Zygobeyn:chia apicalis illrich. 'l'estiferous right valve of the female form. The specimen is perfectly preserved 

except the anterior margin, which is broken away. 'l'he transverse undulations on the anterior lobe seem to be 

normal. U. S. Nat. Mus Cat. No. 61386. 

17. Ctenobolbina (?) cormtta illrich. Gutta-percha squeeze of a natural mold of the exterior of both valves. U. S. 

Nat. Mus. Cat. No. 61355. 

18. Ctenobolbina (?) cornuta Ulrich. Drawing of same with missing parts restored, X 11. 

19. Ctenobolbina (?) cornuta Ulrich. Diagrammatic outline drawing of the two valves in natural position. 

335 

INDEX. 

A. Page. 

Acrocullfl protei. ....................... :......................... 261 

subcarillfltfl.................................................. 261 

Actlnoptorla................................................ .. . . . 183 

boyd!........................................................ 184 

docussfltfl.... ... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ... . 183 

fronsflcifl ...•................................................. · 179. 

humboldt!. •............................................... 1'19, 182 

tonuistrmtr~ .................................................. , 184 · 

Actinoptorcllfl ................................................... 182-193 

flroostookl. ................................. 186, 187-189, 190,321,323 

vr~r. orecta .............................. · .............. 189,323. 

vflr. planicostfl .......................................... 190, 323 . 

boyd!........................................................ 184 

concontrlca .............................................. 190-191,323 

confortr~ns.................................................... 192 

mosoclathrfltfl................................................ 186 

rodlr~lls .....•....................... 184-186,187,191,192,195,321,330 

tonulrr~dir~ta ............................................ 191-192,323 

tonulstrlatfl.................................................. 192 i 

textilis ................................................. ,189, 190,192 ·. 

sp. fJ. . • . . . • . . . . • • • • . . • . . • . . . . • . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 192,332 · 

sp. 'Y. • • • • • • • • • • • • • • • • • • • • • • • • • • • • • . • • . • • • . • • • . . . • • • . • • • • • • • 192, 330 

sp. 6 •••• : ••••••••••••••••••••••••••••••••••••.•••••••••• 192-193,330. 

Adranarla socurirormls........................................... 168 

Agnr~thfl......................................................... 293 · 

Allorlsmu .................................................... ; ... : 130 : 

Allorlsmfl ................................................... , .. 130,133; 

pllcatclla. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . 134 : 

Ambonychifl..................................................... 198 . 

obtusfl....................................................... 149: 

Amltfl ........................................................ :.. 225 

Amnlgenla catskillensfs ....................................... :.. 146 

Anabflifl..... ..... ........ .. . . . . . . . . . . . . . .. . . . . . .. . . . . .. ... . .. .. . 115 

Angollum ................................................. ,...... 147 · 

cunoatum.................................................... 239 

Anodontopsfs .............................................. 236-:-238, 240 , 

angustifrons.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 236, 238, 240, 243, 244 ; 

bulla .............................. ~ .................... 240,257,259 · 

lrovis.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 240 · 

muccoyfana .................................... 220,236-238,331,333; 

qufl<lrotus..... .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . 240 1 

socurlformis ...... :........................................... 240 

vontrlcosa ... '................................................. 248 

Anoplothocfl ......................................... ~........... 119 

flabellites .................................................. 121,122 

Anthozoa ........................................................ 14-15 

Antfarcha..... .. ... ... .. . ..... .. .. .. .. . .. . . . . . . .. . . .. . . . . .. . .. .. . 293 

Antlsplrlfcr ..................................................... 114-118 

harrold!.. .......................................... 115,116-117,308 

var. trrulSvorsa ..................................... ·117-118,307 

ArU1ropoda .................................................... 285-293 

Astartacefl ..................................................... 239-249 

Astarte primula................... ... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 140 

Astartldro ...................................................... 239-249 

Astartopsfs rfchthofenl........................................... . 228 

Asterolepidre. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . , 293 

Asterolepls clarke! ........... , ................................. 293,329 

AU1yrldro ...................................................... 118-126 

Athyris aliena................................................... 126 

sp. nov. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 125 

Atremata .•.•.................................................... 20-21 

Atrypa flabellltes ............................................... 119,120 

palmata...................................................... 120 

singular is.................................................... 69 

ungulformls .................................................. 41,42 

Aucolla.......................................................... 206 

50245°-No. 89-IG-22 

Page. 

.Auriptygma ................................................... 280-282 

fortior ...................................................... 280, 282 

A vicula.. . . . . . . . . . . . . . . . .. .. . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . .. 178 

ala ••..•.•••.....•..... -.. .'.................................... 203 

ampliata ................................................... 178,194 

bohemica. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . 203 

carens........................................................ 211 

chemungensis ............................ : . . . . . . . . . . . . .. . . . . . 208 

comes........................................................ 194 

cometula..................................................... 194 

communis.... . .. . . . . . .. . . . . . .. . . . . . . . . . . .. . . .. . . . . . . . . . . . . . . . 186 

confortans ................. · ........... : . . . . . . . . . . . .. .. . . . . . . .. 184 

correcta.. . . . . . . . .. . . . . . . .. . . . . .. . . .. . . . . . . . . . . .. .. . . . . . . .. . .. 203 

crenatolamollosa var. pseudolrevis. .. . . . . . . . . . . . . . . . . . . . . . . . . 211 

danbyi.................................. ..................... 179 

demissa ...................... : . . . .. .. . . . .. . . .. . .. . . . . .. . . . . .. 194 

dispersa.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 194 

erecta........................................................ 194 

explanata .................................................. ;. 194 

gervillei...... . .. .. . . . .. . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . .. .. . 210 

gratior. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 211 

imperfecta. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 211 

impotens .................................. :.. . .. . . . . . . .. . .. .. 211 

inclinata. .. .. . . . .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . .. . 194 

invisa..... ... .. . . . .. . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . .. . . .... 211 

jacens........................................................ 194 

I revis... .. .. .. . .. .. .... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . 208 

marire....................................................... 184 

naviformis.. ... . . . .. . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . ..... ... ... 194 

obliquata .............................................. 179,181,182 

opportuna ................................................... · 211 

orbicularis................................................... 203 

pauciradiata. . . .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . .. . .. . . .. 203 

pseudolrevis. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 210 

pulchella..................................................... 210 

rectangularis ........................... .'. . . .. . . . . . . . . . . . . . .. . 195 ' 

reinformis.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 194 

reticulata. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 183, 184 

retrofiexa. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 193 

schrenki ... ~ . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 211 

serviens...................................................... 211 

sub plana. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 194 

subspatula..... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 210 

textilis....... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 184 

tristis........ .. . .. . .. . . . . . . . . . . . . . . . . . .. . . . . . . . . . . .. .. . . .. .. . 194 

whitfield! ............... :.................................... 194 

winteri....................................................... 211 

wurmi....................................................... 184 

sp................ ... ..... .. . .... ..... .. . .... ................. 179 

A viculopecten alcis ........................................ 179, 181-182 

fiammiger .............................................. 179,181-182 

incertus.. ... ... .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . .. .. 202 

B. 

Beachia.. .. ... ... .. . .. . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . ... .. . . 71 

amplexa..................................................... 71 

chapman! ................................................... 71,332 

suessana .................... _. . . . . . . . . . . . . . . . . . . .. . . . . . .. . .. . . 71 

Beecher, C. E., work of.......................................... 6 

Bellerophon bisulcatus. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 267 

carinatus... .. .. . .. .. .. . . .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 270 

compressus ............................... ·. .. . . . . . . . . . . . .. . .. 271 

curvilineatus ................................................ 269, 270 

cyrtolites .................................................. 269, 270 

gaspensis .... 0................................................ 268 

g.ill.etianus ... : . .. .. . .. . .. .. . .. .. . . . . . . . . .. .. . . . . .. .. .. . . . .. . . 272 

337 
338 INDEX. 

Page. 

Bellerophon macrostc;>mus........................................ 264 

natator... .. . .... ... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ... . . 264 

patulbs. . . . . . • . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 264 

quadrilobatus................................................ 267 

.revol vens. • . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 265, 320 

rhenanus ........................................... ·.......... 265 

trilobatus .......................................... 265,266-269,320 

var. tumidus ...................................... ·....... 267 

tumidus .•....•................................. .".......... ... 268 

sp. indet. .• .•...... .. . .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 268 

Bellerophontidre ..••........................................... 263-272 

Beyrichia buchiana .••......................................... 290,291. 

devonica .......•....................................... 290,291,292 

kloedena ................................................... 290,291 

ungula ................................. · ..................... 290,291 

Beyrichiidre.... . . . . . • . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 289-293 

Billings, Elkanah, on Cyrtodonta.. .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 149 

on Pteronitella ............ ; . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 193 

Bollia .......................................................... 290,291 

ungula........................................................ 291 

Brachiopoda ............................. ~ ...................... 2Q-126 

Broeckia ....................................................... 131,140 

dorsata...................................................... 141 

latissima..................................................... 141 

mutica....................................................... 141 

prisca.. ..... ...... .. . .. . . . .. . . . .. . . . .. .. . .. . ... .. . . . ... . . . .. . 141 

subequalis... .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 141 

Bryozoa.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19-20 

Bucania freitasi. ; . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 265 

trilobata.. .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 267 

trilobita . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 267 

trilobatus .......................... ·. . . . . . . . . . . . . . . . . . . . . . . . . . 267 

Bucaniella bohemica... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 266 

divergens ................................................... :"-': 266 

inflata ............................... ,....................... 266 

nana...................... ................................... 266 

reissi......................................................... 268 

trilobata• ................................. ."... . . . . . . . . . . . . . . . . 266 

trilobata var. viramundo ......... :. . . . . . . . . . . . . . . . . . . . . . . . . . 268 

Page. 

Chonetes cornuta ..................................... ·. . . . . . . . . . . 48 

~o:;~:~~-- .·: ~ ~ ~ ~ ~ ~ ~ ~::::::::::::::::::::::::::: :·~:::::::::::: ~: ~ deflecta ........................................... : . . . . . . . . . . 50, 51 

deflectus ........... · . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 51 

d.ilatata. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . • 35, 54 

dilatus.............. ...... ....... ........ ... ................• 52 

extensus. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . • 52 

falklandicus................................................. 47 

filistriata. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . • 45 

gibbosa . ." ................... : ..............................• · .. 47,50 

hardrensis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 7 

hemisphericus. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 54 

hudsonicus. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 53 

impensus. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 49 

lata ............................................ !............. 47 

laticosta ...................................................... 50,51 

latus......................................................... 45 

macrostriata, •....................................... ·........ 50 

macrostriatus....................... .. . . . . . . . . . . . . . . . . . . . . . . . 54 

manitobiensis.. .. . . . . . . ... ..... ... .. . ... .. . ......... ......... 57 

melonicus ............................................... 47,52,-53,04 

mucronata ............ : . ........................ , . . . .. . . . . .. . 50 

mucronatus .................................................. 50,51 

novascotica. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . • . . . . . . . . 45 

novascoticus ..................................... 45-4.8,312,314,315 

novascoticus var. canadensis .................... 49,182,314,315,316 

papilionacea.... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45 

plebeia .................................................... 35,47,52 

polytrichia.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47 

pusilla.... .. . . .. . . . .. . . . .. . . . .. . . . . . . . ... . . . .. .. .. . . .. ....... 50 

pusillus ....................................................... 50,51 

robustus................ .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 51 

sarcini.llata................................................... 47 

sarcinulatus. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45,47 

shumardianus.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45 

striatella .. · ................................................... 46,48 · 

striatissimus .................................. 44-45, 46,313, 314,315 

tenuicostata ..................................................• 45, 47 

venustus. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45 

C. vicinus ................................................ 51, 52, 54, 105 

Camarotrechia ................................................... 63-66 vicinus var. defiectus ...................................... 49-52,306 

congregata ................................ , . . . . . . . . . . . . . . . . . . 63 zephyrus. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 48 

contracta. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 63 Chonostrophia. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 55-57 

dryope ....................................................... 64,65 complanata ............................................. 55,182,315 

eximia........................................................ 63 dawsoni. .................................................. 55,56,57 

o.rbicularis... .. ... .. . . . .. .... .. . . . ... . . . . . . . . . . . . . . . . . . . . . . . . . 63 helderbergia.................................................. 56 

- prolitl.ca. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 63 jervensis ........................................... ~ . . . . . . . . . 55, 56 

Canada, Geological Survey of, acknowledgment to................ 5 jervisensis ....................... :............................ 56 

Capulidro.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 259-263 montrealensis ................................................ 56, 57 

Capulus crassus. . . . . . . . . . . . . . . . . . ... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 260 reversa ....................................................... 56-57 

kahlebergensis. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 260 sp..... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 55 

Cardiniidro .................................................... 236-238 Cimitaria ........................................... 131, 132,133,253-257 

Cardiomorpha. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 131 borealis. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 254 

alata ................................... ,. . . . . . . . . . . . . . . . . . . . . . 229 chapmani. ..................................... · .. :. 254, 255-257,331 

vetusta..... .. . . . . . . . . . . . . . . . . . . . . . . ... . . . . . . . . . . . . . . . . . . . . . . . 149 corrugata.............................................. .. . . .. . 253 

·Centronella bergeroni. .................... .' ....................... 75, 124 elongata ........... · ........ , ..... ~ .......................... 253,254 

glansfagea ... :., ....... : ..... , . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 76 karsteni. ........................................... 254, 255, 256-257 

Cephalopoda ................................................... 282-285 , recurva .............................................. ,....... 253 

Cercomyopsis .................................................. 132,254 Clarke, J. :r.f., species described by................................ 11 

Chronomya ..................... , .............................. 130,254 work of...................................................... 6,10 

leavenworthanus ........................ .".................... · 254 Cleidophorus ................................................... 159-162 

Chapman fauna, source of. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 299 brasilianus ..... ~ . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 162 

Chapman sandstone, exposure of................................. curtus .................................................. 16Q-161, 325 

Chondrites....................................................... 35. elliptica...................................................... 168 

Chonetes ...................................................... : .. 44-54 ellipticus..................................................... 163 

acutiradiata....... .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 52 neglectus .................... · ............................... 161,162 

acutiradiatus............................ .. . . . . . . . . . . . . . . . . . . . 54 perovalis ........................... : ................... 161-162,332 

arcei. ........................................................ 47,52 Clio~lya~~~a:~~~~~t~~:: :::::::::::::::::::::::::::::::::: :::::::·:: ;~: arcuata ........... ,.......................................... 53 arcuatus. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 52, 53-54, 105, 306 Cnidaria. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14-15 

armata...................................................... 50 Crelenterata ...................................................... 14-15 

aroostookensis... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45 Crelidium ...........................................•.......... 275,318 

bastini. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 48-49; 313 planogyratum.... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 275 

billingsi...................................................... 51 strebloceras.. .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 273 

bohemicus ................................... ~............... 45 tenue .................................................. 273,274,276 

canadensis ........ ·..........................................• 49 Crelocaulus...................................................... 275 

complanata .... · .............................................. 55,56 davidsoni. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . • . . . . . . . . 275 

comstocki.... .. . . . . . . . . . . . . . . . . . . . . ... . . . .. . ... ... . .......... 47 Crelospira .............................. :. . . . . . . . . . . . .. ... . .•.•.•• 119 
INDEX. ·339 

Page. . Page. 

Conchita rhomboldalls..... .. . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . . . . 32 Cypricard.ites .................................................. 147-156 

Conocardlldro .................................................. 201-202 caswelli................................................ •••••. 133 

Conocardlum .................................................. 201-202 curta .............................................. 148,149,152,154 

brachyplouro..... .......... ... . . . .. . . . . . . .. .. . . . . . . . . . . . . . . . 202 curtus. ..... . ... ... . . . . . . . . . . . ... . . .. . . . .. .. .. ... ............ 147 

dubla .................................................. 2:)1-202,330 detroitense ..... · ........................................ 151H5~330 

Conrad, 'r. A., on Cyprlcardltos.................................. 147 elongatus........................................... .. ....... 147 

on l{fcrodon ............................................... 239-240 modiolaris.................................. ... .............. 148: 

Corbula grogarla.... .. . . .. . . . . . . . .. . ..... . . . . . . . . . . . . . . .. . . . . . . . . 228 rugosa....................................................... 225· 

Comollltos flabella............................................... 194 Cyrtiarostrata ................................................... 76,77 

Comulltos ........................................................ 15-16 Cyrtina .................................................. 76-80,116-117 

chrysalis..................................................... 16 biplicata ..................................................... 79-80· 

clngulatus. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17 dalmani. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 78, ~ 

floxuosn.. . .. . . . .. .. . .. .. .. . . .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17 demarlii ............................................... :. . . . . 77 

floxuosus ....................... , . . . . . . . . . . . . . . . . . . . . . . .. . . . . . 17 hamiltonensis ................................................ 78, 79· 

var. grac_llls..... ... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16 var. recta .............. ,................................. 78 

malnonsls ................................................ 16-17,320 heteroclita 78 79 308 

J Var. alp. h. a. -_ -_ -_-_-_-_-_-_-_-_- _- _ .. __ .. __ .. _ -_ -__ : -_ -__ .. _ -_ -__ .. __ · .. _ __ -_- _- .- .. _ __ .. _ .· .· ·_ .·. -.'. ~,~so.· rna or ................................. ~ . . . . . . . . . . . . . . . . . . . . . . 15 tr"' 

proprius .................................. -... -.. ------. -. -. - 15 var. multicostatn ............ ·. . . . . . . . . . . . . . . . . . . . . . . . . . . . 77 

sorpularlus ................................... -- ....... -.- 15-16,320 var. multiplicata ............. ·.· ........................... 77,78 

C

Corro1IaUon of tho Chapman fauna ........................... --- 2925-

4

29

2

9

5 rvoarst1

·raa_t_a_ ._ ._ ._ ._ ._ ._ . __ .. _ ._ ._ ._ ._ ._ ._ ._ ._ ._ ._ . __ .. _ ._ ._ ._ ._ ._ ._ ._ ._ ._ ._ ._ ._ ._ ._ ._ ._ ._ ._ -_ .. _ ._ ._ ·._ ._ . __ .. _ ._ .7. 6-. _79

7

,

7

3

1 

o

7

s

8

. ran a........................................................... -

bella ........................................ --- ..... -.-.---.- 25 Cyrtodiscus............................................... ... .... 270 

pulcholla.. ................................. -.--- .. ------------ 25 Cyrtodonta ................................................ 147,148-155· 

sp. Jndot ........ · .............................. -..... ---.- 2·1-2.5,310 beyrichi............................................. ... ..... 152 

Cranlacoa .................................................. _., ..... 24-25 declivis.................................................. .... 152 

Cranlldro .......... --.--.---.------------------------------------- 24-25 dunensis ...................................... : ............ 153, 155 

Crustacea ......................................... ~- ..... ~·- .... 285-289 kayseri. ................ _. _ ... _. _. _. ______ . _. _ .. _. _........ ... 152 

Cryptonella oils!................................................. 76 orbicularis.·.................................................. 152 

Ctonobolblna .................................................. 289-290 rugosa ............. _. ______ ...... _. ______ . _ ... __ . ___ ......... 149 

Ctonc~~~~:~ ~ ~::: :::::::::::::::::::::::::::::::::::::::::: -~~-;:~~~:~ Cyrtodontidro .................................................. 147-156 Cyrtodontopsis ............................................ 147,152,153 

al borUnt\ .................................. ·. . . . . . . . . . . . . . . . . . . 173 kayseri. ............. _ . _ ............ _ .. .. . . . .. .. .. . .. .. .. .. .. 153 

astartroformls .... -........ --------.----------.--------------- 158 Cytherodon socialis ............................................ 234,236 

contracta.................................................... 15S 

crassa .................................................. 165,167,170 D. 

dalloldonso................................................... 162 Dalmanella. ·----------------------- ·--------------.---.-· ·-.-... 57~1 ologans .................. _. _ .. ____ ..... ___ ..... __ . _ ..... ____ 163, 164 circularis ................................................. 59-61,312 

glbborula ................. -........ -... ------ .......... --'--- 158 drevermanni. ............... -...... -.--.- .. -- ................ 58,60 

glbbosa .................... -.- ....... -- ... --.---- ... -.. -- .. 165, 166 elevata.- ... -...... -.. -...... -.--.---.- ...... ------.- 62,310,312,313 

ko.y~orl. ................... -......... -.. -- .... ---- ..... -----.. 165 lucia ................... -... -.. -........ -.- ..... -.- ... -- .. ·.... 58 

krotonls...................................................... 162 penouile.- ·-- .. -.. --- .. -------- .. -- ·------ .. ---------.... .... 63 

lovata ........... _ ....... _ .. _. __ ..... _ ....... _ ..... ____ ....... 173 planiconvexa ........................................ 57,58,310,312 

logan!. .......................... _. __ ........ _ ......... ___ .... 158 'planoconvexa ....................... ." .............. 57-59,60,61,312 

no.suta ................. ; ....... __ . _ ..... __ .... ___ ... ____ ..... 158 testudinaria.................................................. 58 

prlmrova ...................... _____ ........... ___ ..... _. ____ . 163 Dalmanites concinnus.... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2.89 

soclalls ................ '....................................... 173 meek!..- .... · .... ----------·------------- .. ---------:.-...... 289 

unlonlformls................... .. . . . . . . . . . . . . . . . .. . . . . . . . . . . . 165 phillipsi. .. -.. ·.· .. -- .. -· .. ------ .. ---- .. ---------------- ... .. 287 

Cucullollo. olllptlca ............................................. 161,168 stommatus var. convergens........................... ....... 289 

lntormodla .. -.. --.-.-----.---.- ·.·-------.-- ... ------.------.. 170 sp. a· .... · ........ --- .. --------------------------.----.-. 288-289,329 

oplma .............. -............... -..... ----..... -..... -. -. - 173 sp. fJ ••••••••••••••••• -• --• -• -•• -• --•••• ---. --•••• -••••••••• 289,329 

Cuncamya .......................... ___ .................... _ 131,132,255 Delthryris arenRria...................................... ......... 84 

Curtonotu~ grobcl................................................ 248 arenosa ...... -------- .. ---------- ·- .. ---------- .. --- ... ....... 84 

torosus .................... -........... -- ...... --- ....... -.... 248 duodenaria ........ -... -- .... -......... -.--.- .... -...... :..... 104 

Cyprlcnrdolla .................................................. 239-249 raricosta · · · · ·- · · · · · ·- ·---- ·-- · · · · .. -.- ·--.-------- .. -.- 101,106, 107 

bollatuil.l ........................................... 244-246,247,328 De Vemeuil on Grammysia hamlltonensis............... ......... 128 

blcost'ulo. ......................... ___ . _ ...... _. __ ... 247,248-249,328 Diaphorostoma...... .. ... . . ... .. .... .. .. .. . . . ...... .. ... ......... 262 

cantralnoana .............. _ ....... __ ...... ______ .. _. _ ... _. _.. 247 ventricosum......... ... .. . . . . . . . . . .. .. .. ........ ............. 263 

curta ............... _ ....... ___ ...... _ ..... __ .......... _ 245,246,247 Discina bainii....... ... . ... . . . . .. . . . .. .. .. .. .. .. .. .. ............. 24 

olongato...... ....... ...... ........ ..... ............. ... ... ... . 249 discus........................................................ 21 

grogarla 245 246 247 forbesii..-- ·----.. -- ·----.... · .. · .. -- · .. ·-- ·- .......... · ..... · 24 

hartll .. :::::::::::::::::::::::::::::::::::::::::::::::: .. __ '_ _ '247 Discinacea ....................................................... 21-24 

240 Discinidre ........................................................ 21-24 

240 Ditichia .................... ~---···············~---··············· 168 

nucloata ......................................... : .......... . 

oblongo. ..................................................... . 

parallola ...................... ·............................... 247 

pllcata. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 230,'240 

E. 

pohll. ................... ·..................................... 238 

rotundata ...................................... 246-247,248,326,328 

Eastm.an, Cha~les R., on Asterolepisclarkei...................... 293 

Eaton1a ..................... : .................................... 67-69 

subolllptica ............................ ·...................... 240 

subovato. ............................................... 245,246,247 

coulter! ........................... :. . . . . . . . . . . . . . . . . . . . . . . . . . 70 

henrici. ..................................... ·. . . .. .. .. . .. .. .. . 70 

tonuJstriata ............................................ 245-246,249 peculiaris................. ... . . . . . . . . . .. . . . . . . . . . ............ 70 

transversa ............................................. 247..:248,328 singularis .............................. ~ ................. 69-71,310 

unionlformis. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 249 EctenOdesma birostratum........................................ 204 

Cypricardia acuti carinata. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 230 Edmondia.. ............... ... . .. . . . . . . . . . . . . . . . . .. .. .. .. .. ....... 141 

contracta.................................................... 235 Edmondia amydalina............................................ 141 

cymbroformis. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 223;224, 256 · debilis ..................................................... 141,143 

glabro.tus. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 230 decorata .................................................. ·.... 141 

rhombea. •............... .. . ....... .. .. ... .. . . . . . . ... . . ... .. . 230 elliptica..................................... ................. 141 
340 INDEX. 

Page. 

'Edmondia grrelata............................................... 141 

nobilis....................................................... 141 

·' prrecox....................................................... 141 

prrelonga .......................... : ........................ 141,143 

0 pulchella..................................................... 141 

' subangulata ..................... ~---························· 149 

subtruncata.................................................. 149 

ventricosa ........................................... : . . . . . . . . 149 

sp. indet. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . 331 

Elymella ....................................................... 140-143 

fabalis ...................................................... 140,142 

harrisi. ................................................. 142-143,331 

Ievata............. .. .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . 142 

missouriensis................................................. 142 

nuculoides .................................................. 140, 142 

End~~:~~~~-~~~;;~~~~::::::::::::::::~:::::::::::::::::::::::: ;~~ cuneatum ............................ · ..... ·................... 222 

~~~~~~t~~::: ::::::::::::::::::::::::::::::::::: :·::::::::::: 

postlatum ................................................... . 

undosum .................................................... . 

Ensis americana ................................................. . 

ensis ........................................................ . 

222 

222 

222 

222 

253 

253 

gracilis. . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 253 

Eodevonaria. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 52-53 

Eodon.. ......................................................... 241 

Eotomaria hitchcocki .......................................... 277, 278 

Eunella................................. ..... ... ........ .. ... .... 76 

ellsi ........................ ·.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 76, 311 

sullivanti. • • • . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 76 

Euomphalopterus alata var. Iimatoidea... .. ... . . . . . .. . . . . . . . . . .. 277 

alatus..... .. .. .............. ... ... .. . .. . .. .. . . . . .. .. .. . . . . .. . 276 

conoidea .............................. ~....................... 277 

F. 

Favositessp. indet ........................................... 14-15,329 

Favositidre ....................................................... 14-15 

Fenestella lilrea .................. ~ . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20 

Folmannella ............................................... 178, 179-182 

danbyi....................................................... 179 

fronsacia . .. . .. . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 182 

mainensis.. . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . .. 179-182, 194, 322, 323 

ostreiformis ............................. .-. . . . . . . . . . . . . . . . . . 179, 182 

G. 

Gastropoda. . . . . . . • . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 259-282 

Glossites ....................................................... 143-147 

amnigenoides .......................................... 145-146,326 

amygdalinus. ~ .. ........ ...... .. .. . . . . .. . . . . . . . . . . . . . .. . . . ... 143 

barrandii ............................................... 144-145,325 

depressus .......................................... 144,145,146-147 

ellipticus..................................................... 143 

lingua lis .................................................... 143, 145 

patulus.... .... . . .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 146 

procerus............................................... .. . . . . . 146 

subtenuis..... .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 143 

teretis ...................................................... 143, 146 

Olyptodesma erectum............................................ 194 

Goniophora .................................................... 223-233 

acuta......................................................... 228 

applanata.................................................... 226 

bellula....................................................... 224 

binotata. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 225 

bipartita ................................................... 226,232 

crelata..... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 228 

carinata..... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 147, 225 

carpomorpha.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 229 

chemungensis. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 225 

consimilis. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 224, 225, 229 

crassa. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . .. 217, 229 

cymbreformis ........................... 223,224, 225, 226, 227, 228, 229 

dubia ...................................................... 229,230 

glauca ...................................................... 225, 226 

hamiltonensis ................ : . ........................ 225, 226, 228 

'· imperfecta............................................... ... . 225' 

kayseri. ............................................ 2.'30-232, 233, 326 

media........................................................ 225 

mediocris .................................................. 224, 230 

Page. 

Goniophom minax. ............................ ;................. 225 

minor ...................................................... 228, 230 

modiomorphoides. . . . . .. . . . . . . . .. . . . .. . . . . . . . . . . . . . . .. . . . . . . . 228 

obliqua...................................................... 227 

omega .................................................. 232-233, 331 

perangulata ................................................ 226,228 

phrygia ...................................................... · 225 

pugio .............. _.......................................... 225 

rara.......................................................... 225 

reluctans. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 225 

retrorsa...................................................... 225 

rhombea •................................................. , 223,228 

rugosa........................................................ 228 

scalena. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 225 

secans ...................................................... 225, 228 

soror...... .. .. .. . .. . . . . . . . . . . . . . .. . . . . . . . . . . . . . . .. . . . . . . .. . . . 225 

speciosa ............... .'...................................... 229 

testis......................................................... 225 

transiens ................................................... 224,225 

trapezoidalis ............................................... 230-231 

trentonensis.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 229 

trigonfa .................................... :. . . . . . . . . . . . . .. . . 233 

zephyrina.................................................... 225 

sp. indet. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 230 

Goniostropha. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. .. .. . 276 

chapmani. ................................................. 276,317 

Gosseletia. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 152 

Grammysia abbreviata . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 128 

acadica... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 135-136, 331 

alveata ..................................................... 134, 138 

anomala var. rhenana. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . 128 

arcuata...................................................... 132 

bisulcata ..................... : ......................... 128,129,134 

canadensis. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 133, 137 

cingulata.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. .. 136 

circularis. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. .. 130 

cotentina... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 129 

duplicata ................ :. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 134 

exarata...................................................... 136 

geologic range of.. .......................................... 132-133 

glabra.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 134, 139 

globosa... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 134 

hamiltonensis .............................................. 128-130 

history of. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 128 

inreq ualis. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 134, 137 

interplicatus. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 138 

irregular is .................................................. 128,129 

lrevis.... .. .... .. . .. . . . . . . . . . . . . . . . . . . . . . . . . . . . .. .. . . . . .. . ... . 128 

limits of.. .................... · .............................. 130-132 

lirata ....................................................... 134,138 

Iundi. .............................................. -:-......... 134 

marginata.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 128 

minor........................................................ 134 

modiomorphre. . . . . . . . . . . . ... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 138,330 

nodocostata var. eifeliensis................................... 128 

obsoleta ........................................... ·.. . . . . . . . 132, 134 

ovata. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 128, 129, 136 

prrecursor.................................................... 131 

princiana .............................................. 136-138,327 

species of.. ................................................. 133-139 

triangulata................................................... 134 

type species of.. ............................................ 128-130 

ulrichi. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 134 

undata ..................................................... 134, 139 

sp. indet ................ :............ .•. . . . . . . . . . . . . . . . . . . . . . . 134 

Grammysiidre .................................................. 127-147 

Grammysioidea.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 133-135 

elymelloides ............................................ 138-139,331 

Gyrichnites ....................................................... 17-19 

gaspensis ...........................••........................ 18, 19 

H. 

Hall, James, on Cimitaria. ...... ... . . .. ... . . ... . . .. . . . . . .. . . . . .. . 253 

on Cypricardella. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 240 

on Cypricardites .......................................... , 118, 150 

on Elymella ................................................... 140 

on Glossitcs ................................................ ·.. 143 

on Megambonia.............................................. 198 

on Modiolopsis ...................................... :. . . . . . . . 148 
INDEX. 341 

Page. 

Ball, I amos, on :Modiomorpha................................... 216 

·on Palrcarca ............................................... ,... 150 

on Sphcnotus. . .. . .. . .. . .. . . . . . . . . . . .. .. . . . . . . . . . . . . . . . . . . . . . 235 

on :.J'ciUnomyn .............................................. · . 157 

Bcldorborgio.n rauna, correlation or tho Cbapmo.n fauna wit.h .. 295-299 

Homlpronltos cllomungonsls var. arctostriata...... .. . . . . . . . . . . . . . 35 

Hercynian fauna, correlation or tllo CJ1apmo.n Janna with .... 29&-299 

Boxncomlla ...................................................... 14-15 

Hipparlonyx .................................................. 40,11-43 

proxhnus ................................................. 41,42,43 

unguirorrnls ................................................. 41,312 

Holopca.... . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 281 

bcushausonl.. ........................................... 281-282,317 

syrnrnotrlca .. , .. . . . . . . .. . . . . . . . . . . . .. . . . .. . . . . . . . . . . . . . . .. . . . 281 

Rolopclla obsolcta................................................ 273 

Bornalonotus .................................................. 28&-287 

dolphlnoccpllalns.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 286 

latlcaudatus ............................................ 28&-286,329 

vo.nuxomi. ....................................... : ..... 286,287,329 

Hughes, '1'. M., upper boundary of tile Silurian established by... 5 

I. 

Diona............................................................ 257 

Inoceramus mytilimerls .......... .'.. .. .. ..... .. . . . .. . . . . . . . . . . .. . 215 

Isooardlaolongata... ......... ... ... .. . . .. . . .. ... . . . . . . .. . . .. .. . . . 131 

fncumbons................................................... 131 

latlsshna....... .... . . .. .. .. .. .. . .. . . .. .. . . . . . . . . . . . . . . . . .. . . . 140 

I>ollons...................................... .. ............... 131 

Isoculla ........................................................ 131-132 

K. 

Koforstofn, Christian, on Mocy:nodon............................. 2'1:7 

Klpodonfa........................................................ 291 

Kochia.... .. .. .................. .. ....... ... .. .. .. .. .. . . .. . .. . . . . 225 

Kocnonfa ...................................................... 163-167 

L. 

Leda .......................................................... 171-172 

brovlrostrls.................................................. 172 

harris!. ................................................ 171-172,332 

minuta ..................................................... 172,333 

mira......................................................... 168 

Lcdopsis porobliqua..... ... . . . . .. . . . .. . . . .. .. . .. .. .. .. . .. . . . .. . . . 176 

trigona....................................................... 177 

Loiopteria .............................................. 178, 196, 208-212 

bigs by f.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 209 

Conradi....................................................... 209 

dokayi. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 208, 209 

gabbi. ............... ··········· .... .... .... ................. 209 

grandis........................ .. . . . . . . .. . . . . .. . . . . . . . . . . . . . . . 210 

grooni. .. .. . .. . .. .. .. . . . . . . . . .. .. . . . . . . . . . . . . . . .. . . . . . . . . . . . . . 209 

hawkinsi. .................................................. 210,212 

hlrundo...................................................... 210 

Imvis.... ... . . . . . . . . . . . . . . . .. .. . . . . . . . . . . . . .. .. . . . . . . . . .. . . . . . 209 

laminosa.... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 210 

loucosfa. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 210 

llnguiforrnls.................................................. 209 

Ungulata ................................................... : . 210 

longirostrls................................................... 210 

lnnulata...................................................... 210 

maccoyl... .. . . .. . .. . . . .. .. . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . '210 

mitchollf.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 209 

obtusa ....................................... · ........ : . . . . . . . 210 

phfllfpsl...................................................... 210 

I>icta............ ........ .......... ........................... 210 

raflnosquf. ................................................. 208,209 

rafi.nosqull............ .. . . . . . . . .... . . . . . . . . . . . . ... . .. ... ... ... 179 

rfosfo.na ............................................ 209,211-212,325 

sayl... .. .. . . . . . . .. . . . . . . . . . . . . .. . . . . . . . . .. . . . . . . .. . .. . ..... .. 209 

thompson!. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 210 

torrey!. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 209 

vfonnayi. .. . .. .. . . . .. . .. . . . . . . . . . . . . . . . . .. . . . . . . .. . . . . . . .. ... 210 

Lop trona ......................................................... 32-33 

bfpartita..... . . . . . . . . . . .. . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . .. 27 

doprossa........................... ... . . . . . . . . . . . . . . . . . . . . . . . . . 32 

devonica.. .. . . . .. . . . .. .. . . . . . . .. . . . . . . . . . . . . . . . . .. . . . . . . . . . . . 41 

orbicularis................................................... 00 

quadrllatora ...................... ,. .. .. . . . . . . . . . . . . .. . . . . .. . .. 32 

Page. 

Lcptrona rhomboidalis ....................................... 32-33,313 

tenuistriata ............................................. · ...... 32,33 

umbraculum................................................. 34 

unguiformis.................................................. 41 

vetusta......................... ... .. .. .. ...... .. ............. 34 

vicina........................................................ .49 

sp............................................................ 27 

Lcptocoolia ..................................................... 119-124 

acutiplicata ................................................ 120, 121. 

concava ........ ~ ......................................... .'... 119 

fimbriata..................................................... 120 

flabellites ........................... 31, 117, 119, 12~124, 182,308,309 

propria....................................................... 120 

Leptodesma ................. : .............................. 178,209,210 

aliform c .................................................... 195, 196 

extenuatum.................................................. 195 

hector........................................................ 195 

Leptodomus ............ , .............................. 130, 131, 132, 133 

barrosi. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . 229 

borealis. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . 254 

co.nadensis ................................................. 133, 134 

intcrplicatus . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 134 

latus.......................................................... 229' 

mainensis. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 131 

posterns...................................................... 229' 

truncata ............................... , . . . . . . . . . . . . . . . . . . . . . 131 

truncatus.................................................... 14<t 

Leptostropbia .................................................... 25-32 

bcckei.... .. ... . .. . .. .. . . . . . . .. .. .. . . . . . ... . . . . .. .. .. . .. . ... . . 30 

becki. ..................................................... 25, 28, 31 

bipartita ..................................................... 25, 32 

blainvillci.. ........................................... 25,30,31,182 

~:::::~~::.-. ~: : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : ~:: ~~ deltbryris.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25 

filosa .................... : ................................. 25,31,32 

fragilis....................................................... 25 

gilpeni. ...................... ....... ......................... 25 

interstrialis.................................................. 25 

irene ............................ :............................ 25 

julia......................................................... 25 

junia......................................................... 25 

lincklroni . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25 

magnifica .......... • .......................................... 25,31 

parva. .................... ............................... 29 

magniventer. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25 

nearpassi.... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25 

nervosa.. .................................................... 25 

oriskania .................................................. 25, 29,31 

omatella.·.................................................... 25 

perplana .................................. 25,27-32,182,298,313,316 

planulata ................................................. 25,31,32 

pleuristriata . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . 25 

prisca..... .. ............... .. . . . . . . . .. . . . . . . . . . . . . .. .. . . ..... 25 

tardifi... .. ........ .. .. . . . . . . . . . . .. . . .. ... . . ... .. ..... .. . . . . . . 29· 

textilis....................................................... 25 

tullia .................................................. 25,29, 31,32' 

tulliensis.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25 

Limoptera. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 202-205 

ala........................................................... 204 

bifida. ............................. .......................... 202· 

bohemica. . . .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 203 

gigantea...................................................... 203 

longialata. .. ................ .. . .. . . . . . . .. . . . . . . . . . . . . . . . . . . . . 202: 

macroptera .................... , ................... 183,202,.203,204 

obsoleta...................................................... 203. 

pauciradiata. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 203, 205 

var. chapmani ..................................... 204-205,330· 

pauperata.......... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 203. 

rhenana...................................................... 203 

sarmentica.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 203 

semiradiata .". . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 202 

volitans...................................................... 203-

Lingula . . . .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2Q-21 

artemis...................................................... 21 

cornea....................................................... 21 

ilsm.................... ..... .. . ... . .... ........ .............. 21 

ligea.. ............................................. ........... 21. 
342 INDEX. 

Page. 

Lingula longissima ...................................... :. . . . . . . 21 

minima...................................................... 21 

minuscula ............................................. :. 20-21,311 

Lingulacea .......................................... ·. . . . . . . . . . . . . 20-21 

~=~a00br~~i:::::: :·::::::::::::::::::::::::::::::::::::::::. i9~~:~ Lissopleura equivalvis ........................................... 74-75 

Localities where specimens were obtained ................... 7-10,12-13 

Loxonema ............................. -: .......... ·. . . . . . . . . . . . . 279-280 

compacta..................................................... 274 

jerseyense .............................................. 279, 280~ 318 

planogyrata ................................................ 275,318 

subtilistriata ........................... · . . . . . . . . . . . . . . . . . . . . . . 280 

welleriana ................................. _ ............ 279-280, 318 

Lucina elliptica var. occidentalis................................. 257 

prisca ................. ; ..................................... 257-258 

Lucinacea ...................................................... 257-259 

Lucinidre-................................. _ . . . . . . . . . . . . . . . . . . . . . 257-259 

M. 

McCoy, Fred~ric~, on A~o~ontopsis .......................... :... 240 

on Sangumolites demp1ens ........ , . . . . . . . . . . . . . . . . . . . . . . . . . . . 256 

·Macrochilina ................................................... 280-281 

acuta ........................... -. . . . . . . . . . . . . . . . . . . . . . . . . . . . . ' 280 

arculata. : . ............ -•.............. ~....................... 280 

Mapleton sandstone, exposure of. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 

Matercula....... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 225 

Matheria rugosa. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 218 

.tener .............................. : . . . . . . . . . . . . . . . . . . . . . . . . . . 217 

Mecynodon .•.......................................... 226,227, 228,229 

auriculatus ................... : ............................. 227,228 

carinatus ................................................ · ... 227, 228 

concentricus. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . · 228 

oblongus.... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 227 

Megalanteris .............................................. .' ..... 71,123 

ovalis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 71 

thunii. ........... -... -.... -. -...... -. ' ........ -.............. _. 71 

sp .....••................................................ 71,310,312 

Megalodon curvatus ........................................ 133, 138,223 

Meg~~~~~~-:::::::::::::::::::::::::::::::::: :: :::::::: ::::::::: ~~~ Megambonia ........................ .' .......................... 197-201 

aviculoidea................................................... 198 

bellastriata................................................... 199 

bellistriata •............................................ 198, 199,200 

cardiiformis ........................................ 198, 199-200,331 

var. parviuscula •....................................... 201,326 

_cordiformis............ . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 198 

crenistriata ........................................... _ ..... 199,200 

denysia. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 199 

lamellata..... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 198 

lamellosa.... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 198, 210 

lata ............................................... :. . . . . . . . . . 198 

mytiloidea. ........... .. . . . . . . . . .. . . . . . . .. . . . . . . . . . . .. ... . . . . 198 

oblonga ............................................ 198,205,207,208 

obscura. ·. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 198 

ovata ................................................ , . . . . . . . 198 

ovoidea .................................................... 199,200 

ovoides.............. .. . . . . .. . . . . . . .. . . . . . . .. . . . . . . .. . . . . . . .. . 19-i! 

parva ................................. ,.. ... .. ............... 199 

rhomboidea....... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 198, 199 

spinneri. ................ -.-.... .. .. . . . . . . . . . . . . .. . . . . . . .. . .. . . 198 

striatocostata....... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 198 

suborbicularis................................................ 198 

Megerlia lima.................................................... 75 

Merista bella . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 124 

oblata ................................................ '....... -125 

Meristella ...................................................... 124-1'25 

bella ................................................... 124-125,310 

didyma.·.......................... ........................... 125 

meta. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 125 

Mesocoolia ...................................................... 273-275 

compacta ..................... · ............................. 274-275 

compressa............. ...... .. .. . . . . .. . . . . . . . . . . . . .. . ... .. ... 274 

obsoleta...................................................... 274 

tenuella ..•.....•................ ; ...................... 273-274,318 

Mesomphalus hartleyi........... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 291 

Page. 

Microdon ......................... ~ ............................. 239-240 

bellistriata ..................... _ .. : .................... 239,241, 244 

complanatus ................... _ ..... _ .... _ ................ 241, 244 

gregaria, ........ __ ..... _ . _ .. __ . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 241 

major ................. _ . _ ..... __ ..... _ .... _ ............ 24'2, 243, 244 

reservatus .. _ .......... _ ................. _ . . . . . . . . . . . . . . . . . . . . 241 

. tenuistriata ........... _ ....... _ ..... _ ..... _ ................ _ . 241 

Microdonella ............... _ ..... _ ................. _ ..... _ .. .. .. . 241 

l\Iicropteria ......... _ ..... _ ........ _ .... __ ... _ ............ _ ...... · 178 

Modiola annulosa .......... _ ...... _ ............ __ . . . . . .. .. .. . . . . . 206 

antiqua ... .. : . ............................ _: ............... _. 154 

semisulcata .............................. _ .... _ . . . . . . . . . . . . . . 138 

Modiolodon ...................... _ ..... _ . _ . . .. . . . . . . . . .. .. . . . . . . . 218 

Modiolopsidre ............................................ _ . . . . . 216-236 

Modiolopsis ...... ~ ....................................... _ . . . . . .. 148 

antiqua ................................. : .. ................ 222,223 

carinata.... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 229 

dollfussi. ....................................... _ ...... _.. . . . . 216 

latus ......... ·................................................ 149 

modiolaris ........... : ... .... _ ....................... _....... 217 

recta .......... :. . . . . .. . . . . . . . . . . . . . . . .. . . . . . . . . . .. . . . . .. .. . . . 217 

subspatulus.................................................. 149 

thecoides...... .. .. . ... .. . .. . . . .. .. . . . . . .. . .. . .. . . . . . .. . .... . . 216 

Modiomorpha ....................................... _ .. 216-223,228,233 

affinis........................................................ 218 

alta ... :...................................................... 220 

aroostooki .......................................... 219-220, 237,328 

chapmani .............................................. 221-223,327 

complanata ............................................... _ 220, 221 

concentrica ................. _ .............................. 216,218 

elevata ...................................................... _ 218 

follmanni. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 153, 155 

hyalea... ... . . . . . . .. .. .. . . .. . . . . . . .. .. . . . . .. . . . . .. . . .. . . . . . . . 222 

IIllicilenta ..................... · ........................ _. . . .. . 218 

mytiloides .............................. _ ........... _ ...... 216,218 

protea ............................................ :. 219,220,328,333 

rigida. .... .. ... . . . .. . . . . .. ... . . . .. .. . . . . . .. .. . .. . . . . . . . . . . . . . 146 

schoharie... . . . . .. . .. . . .. .. . . . . . . . . .. . . .. . . . . . . . . .. . . .. . . . . .. . 221 

sellowi...... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 155, 156 

submissa ........ : . .......................................... _ 218 

subrectangularis.... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 239 

vulcanalis... .. . . .. .. . . . . .. . . . . . . . . .. .. .. .. . . . . . .. . . . .. . . .. . 219, 238 

sp. indet: ... .. . ..... . .. . .. .. . . . . . . .. .. .. .. . . . . .. . . . . ... . . .. . . 221 

Mollusca. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 126-285 

Molluscoidea.... . . . .. . .. . .. . . . .. .. .. .. .. .. . . . . . . . . . .. . . .. . . . . . . . 19-126 

Moose River sandstone, correlation of fauna of. ............ · ..... _. 299 

species from ................................................ 6,12-13 

Murchisonia..... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 273 

angulata ..... : ............................................. 274,276 

bivittata.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 275 

cingulata .. _ ................................................. _ . 275 

compressa .................................................. _ . 273 

egregia..... . . . .. .. . . .. . . . . . . .. . . .. .. . . .. . . . . . . .. .. . . . . . .. . .. . 275 

extenuata .................................................. ,. 276 

hebe......................................................... 273 

hercynia... .. . . . . . . . . . . . .. . . . . . . .. .. . . . . . .. . . . .. . . . . . . . . . .. . . 276 

logani..... .. . .. . . . . . .. .. . . .. .. . . . . . . . . . .. . . . . . . . . . .. .... ..... 274 

longispira. .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 274 

losseni................. .. . . . . .. .. . . . . . . . . . . .. . . . . .. .... .... ... 274 

macrospira. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 276 

micula. .. . . . . . . . .. . . . . . . . . . . . . . . .. .. .. . . .. . . .. .. . . .. .. . .. . . . . 276 

minuta....... .. . . . .. . . . . . . .. . . . . . . . . . . . . .. . . . . . . .. . .. . . .. . ... 276 

obtusangulata ................... ; .................. _ ....... _. 275 

Myacites ............. · ........................................... : 130 

Myalina.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 212-216 

angulata. ... . . . . .. . . .. .. . . . . . . .. . . . . . . . . . . .. . . .... . . . . .. . . . .. 214 

bilsteinensis................... .... . . . . . . .. . .. . . . . .. . ... .... . .. 212 

egregia ...... · ............................................. _.. . 215 

gooensis ................................ _ ..... _ .. _ .......... _. 215 

lodanen<>is ........................................... __ .. .... . 212 

~aureriana ..................................... 212,213-215,324,326 

var.lata ............................................ 215,324,326 

var. pterinreoides ................................ _ . . 215-216, 326 

pterinreoides ...................................... __ ...... _ 215,216 

rhenana .................... · ........... _ ...... _ . _ . . . . . . . . . . . . . 212 

subquadrata ......................................... _....... 215 

Myalinidre. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 212-216 
INDEX. 343 

Page. 

Myalinodontn .................................................. 202,203 

uor1nu.nlnnn .............................................. ~... 202 

Mynlinoptom orinlta ........... :. . . . . . . . . . . . . . . . . . . ... . . . . . . . . . . . . 199 

1\Iyall.noptorlo....... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 199 

alplnu......................................................... 199 

Myoplusla ...... · ................................................ 162-163 

ohapmmli. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 162-163, 332 

Mystrophorn.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 61 

clovutn. .. . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. .. .. . 62 

1\{ytllurcn ........................................... ·. . . . . . . . . . . . . 212 

Mytillmorphn ............. :...................................... 228 

Alytilltcs......................................................... 196. 

Mytilus gmdutus................................................. 154 

n1ytllin1cris.................................................. 215 

}Jcrovnlls ................................................... 257,258 

plntyphyllus vnr. fJ .......................................... · 222 

quadratus ................................................. 257,259 

N. 

Nniadacoa ...................................... ." .............. 236-238 

Nootr01nata ................................................. ~ .... 21-25 

Nucloosplm .................................................... 118-119. 

vontrlcosa ......................................... 118-119,123,309 

Nucuh\ ........................................................ 173-174 

bolllstriata................................................ ... 175 

coarctata..... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 161 

!ornicntn ................................................... 174,175 

grogaria... .. .. .. . .. . .. . . . . . . . . .. . . . .. .. . . . .. . . . . . .. .. .. . .. .. . 228 

houghton!.. . . . . . . . . . . . .. .. . . . .. . . .. . . . . . . . . . .. . . . .. .. .. .. .. . 173 

krachtte..................................................... 172 

llrnta........................................................ 173 

lodauonsls ..... :. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . • 175 

ophnt\ ........ · ......................... : ................... 173,174 

pohnonsls................................................... 174 

porcrossa ................................................... 1

• 174 

pornuln...................................................... 173 

rondalll...................................................... 173 

sandborgorl.................................................. 175 

shumardlana................................................ 173 

unlonlforn1ls............................. ... . .. . .... . . ... .... 165 

varicosa.. .. . . . ...... ........................................ 176 

Nuculucoa ....................... · .............. · ................ 156-177 

Nuculnna socuris................ ...... . . ... .... .. .. .. . . . ........ 168 

Nuculldm ...................................................... 172-177 

Nuculltos bronnorl............................................... 161 

coarctata.................................................... 160 

oblongus ................................. · .................. .'. 174 

r:~qn~~~o~~-- ·.:::::::::::::::::::::::::: :·;::::::::::::::::::::. i60, ~~~ Nuculoldoa .................................................... 173-177 

aquisgrononsis ......................................... 174,176,325 

bellntula ............................................ 174-175,177,325 

cordabt.. ........................................... 174,175-176,325 

dllfidons... ......................... ......................... 176 

lirota........................................................ 174 

nlotlca....................................................... 174 

ophua... .. ........................................... ....... 174 

putHia....................................................... 177 

rondalll...................................................... 174 

trigonalo ........................................... 174,176-177,325 

Nynssn subalata................................................. 155 

Nylander, Olaf 0.; collection by................................. 5 

0. 

Page. 

Orthis creuistria...... ........................ .. . . . ... . ... . ...... 34 

creuistrla var. devonica...................................... 41 

deformis. . . .. . .. . .. . .. .. .. .. .. .. .. .. .. . . . . . . . . . . . . . . . .. .. . .. . 40 

devonica ....... : .......................................... 34, 35, 41 

distorta. .. . . .. .. . . . . .. . . . . . . . .. . . . . . . . .. .. .. . . .. .. .. . . .. .. .. . 41 

elegantuln................................................... 59 

eminens ...... ·............................................... 63 

expansa.... ................................................. 57 

grondis...................................................... 57 

hipparionyx. ~ ......................................... 34,35,41,42 

hipponyx.... ... . . . . . . . . . . . . .. ... . .. .. . . .. .... .... .. ......... 34 

lewisi................ ........................................ 61 

lucia ...................................................... 57,58,59 

orbicularis. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . • • 59 

palmata.... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . • 120 

planiconvoxa..... ..... .. .................................... 58 

planoconvoxa ..................... , .......................... 57,58 

strigosa...................................................... 35 

sulivnni.............................................. .... .... 34 

sulivnnti. .............................................. :..... 36 

tenuis. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 55, 57 

umbraculum ................................................. '34, 35 

=~~~~i~::::::::::::::::::: :·:::::::::::::::::::::::::::::: 41, :~ Orthisina umbraculum... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35 

Orthoceras ......................................... · ............ 282-283 

norumbogm ........................................ I.. • • • • • • • • 282 

parlineuso ............. ·. . . . . . . . . . . . . .. . . .. .. .. . . .. .. .. .. . .. . 283, 319 

princiana. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 282-283, 318 

Orthocoratidm .......... ·.·.· .................................... 282-283 

Orthodesma .................................................. :.' 126-127 

carinifora .................................... · ........... 126-127,325 

recta.· .................................................. :.. . . . 126 

Orthonota carinata ............................................. 249,250 

ensiformis. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 249 

incerta..... . . .. .. . .. . .. . . . . . . . . . . . . . . .. .. .. .. .. . .. .. . .. .. .. .. 223 

pholadis. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 249 

rigidnn........................... ............................ 252 

siliquoidea ...............................................•• 249, 250 

simulnns ............................... :. . . . .. .. .. . .. .. .. • • • • 223 

solenopsis .. : .............................................. ~ 144, 145 

speciosa.............................................. .. . . . . .. 223 

undulata ............................................... 249,250,252 

Orthonotus cymbmformis. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 224 

nasuta ........................................ ,.............. 224 

semisulcatus .......................... , . . . . .. .. .. .. .. . .. . .. 138, 224 

Orthonycbia hobos............................................... 261 

Orthostrophia canadensis. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 63 

Orthothotcs agassizi.. .................................. ,.......... 37 

chemungeusis .......... ·. . . . . . . . . .. . . . . . . . .. .. .. . .. .. .. .. .. . • . 36 

arctistriatus .............................................. · 37 

var. pandora ..................... :. . . .. .. . . .. . .. .. .. . .. . . 36 

deformis ...... ·. .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. .. . . .. . .. .. .. 40 

hipponyx. .. . . . . . . . . . . . . . . . . . .. . . . . . .. . . . .. .. .. .. .. . . .. . . . . • • 36 

pandora ...................................................... 37,39 

sulivani............................................. .. . ....•• .37 

umbraculum................................................. 36 

woolworthana... . .. . . . . . . .. . . . . . .. . .. .. .. .. . .. . .. . .. . .. . .. . .. 36 

woolworthanus... .. . .. . . . . . . . . . . . .. . . . .. . .. . .. . .. .. . .. . .. .. .. 37 

woolworthanus gaspensis..................... ... ... .. ........ 37 

sp. a . . . ..................................................... 36 

sp. fJ ......................................................... 36 

Ortonia ..................................................... : .. . . 16 

Ontaria ......................................................... . 258 iutermedia..................... ........ ...................... 17 

225 Ostracoda ........... __ .......................................... 289-293 Onychia ........................................................ . 

Orblcula balnll. ................................................ . 24 Oxydiscus imitator.............................................. 270 

miuimus.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 272 

orbiculus... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 272 Orblculoidoa ..................................................... 21-24 

bnlull........................................................ 24 

discus ................................................... 21-24,311 

lllOiltls....................................................... 24 

Orthldm ....... .' .................................................. 57-63 

Orthls areola... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 61 

!\Ylllaro...................................................... 120 

cnllnctls...................................................... 120 

clrculnrls ................................................ 59,60,297-

conciuna...................................... ... ............ 27 

conrodL . . . . • .. .. • • . . . . .. .. .. . . .. .. . . . .. . . .. .. . . . . . . . . . .. .. .. 41 

P. 

Palmarca ................................................... 147,149,151 

saffordi. ................................................... 149, 150 

ventricosa .................................................. 149, 150 

Palmoneilo boyosei. . . . . . . . . . . . . . . . . . . . . . . .. . . .. .. . . .. .. .. .. . .. . .. 166 

folies ....................................................... 168,170 

mainonsis ......................................... :.~ ........ 168 

neg leota. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 165 

occulta. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 165 
344 INDEX. 

Page. 

PalaJoneilo orbignyi ............................................ 15, 167 

perplana .................................... ~ ............. : l63, 167, 

prisca ............................... , ... _.,... ... . .. . . . . . . . . . . . 170 

virginica ................................................... 163,167 

PalaJonustus ................................................... 276-277 

PalaJopinna ................................................. : .. . .. 196 

Paleoneilo ................................. · .................... ·168-170 

angusta.................................................. ... . 163 

bisulcata. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ... . . . . . . . . . . . . . . 163 

brevicula ............................................. ~... .•• 177 

circulus ................................................ _._ . . . . 166 

constricts .............................................. 163,170,174 

crassa.... .. . .. ... . . . .. . . . . .. . . . . . . . . . . . . . . . . . . . . . . .. . . . ...... 170 

illtermedia................................................... 170 

mainensis ...................................... 168-170,325,326,332 

var. umbonata .......... ; .............................. 170,332 

muricata...................................................... 163 

speciosa...................................................... 170 

sulcata ..................................................... 163,167 

sulcatina..................................................... 162 

Paleosolen ..................................................... 249-253 

belgica· ....................................................• ·. . 252 

chapmani .......................................... 2fl(), 251-253, 331 

costatus ..................................................... 250, 252 

eifeliensis. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 250 

occidentalis. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 250 

siliquoidea.................................... . . . . . . . . . . . . . . 250 

simplex..... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 250, 251 

Paracyclas ..................................................... 257-259 

bohemica. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 257 

bulloides ............................................... 258-259,332 

elliptica...................................................... 257 

lebesconti. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 257 

lirata ...................................................... 257,258 

occidentale.... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 257 

Paropsis ....................................................... 202,203 

Patellostium .... , . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 264-265 

Pelecypods. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . • • . . . 126-259 

Pentagonia ........ : . .......................................... 125-126 

unisulcata................................................ .. . 126 

Ph~~~~n:r;~~~~~: ~::::::::::::::::::::::::::::::::::::::::. ~~~~26, ~!~ downing!. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 287 

glockeri. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 287 

pupillus ...................................... ·.·. ..••.......... 287 

Phacopidella ................................................... 287-288 

anceps. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 287, 288 

brasiliensis .......................... ,........................ 287 

chapmani. ............................................. 287-288,329 

glockeri. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 287 

nylanderi. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 287 

Pholadella ................................................. -132, 133,254 

parallels ............................................ ·. . . . . . . . . 254 

Pholadomya .... : . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 130 

anomala..................................................... 128 

Phragmostoma. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . 264 

cunulaJ ................... , . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 264 

cymbula..................................................... 264 

incisum. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 264 

nata tor ............. ; . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 264 

Physetomya ................................................... 139-140 

acuminata ..... : . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 132 

sp. indet .................... : ................ · ........ < ••••• 140,333 

Planorbis trilobatus.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 267 

PlantaJ ........................................... ·............... 293 

Platyceras. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 259-262 

aroostooki. ................................................. 261,319 

chapmani. .. , .......................................... 259-260;318 

compressa .................................................. 262, 319 

conoideum ....................................... -............ 262 

edmundi. ........................................................ 260,318 

elongatum................................................... 261 

hebes. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 260, 261, 318 

var. a .......................... · ............... , .... 260-261,319 

var. {J • ••••••••••••••••••••••••••••••••••••••••••••••••• 261,318 

· kahlebergensis............................................... 259 

protei........................................................ 261 

Page. 

Platyostoma ................................................... 262-263 

arenosa...................................................... . 262. 

ventrico8a ..................... ·.· ........................... 262,263 

ventricosum ........................................... 262-263,318 

Plectambonites rhomboidalis. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33 

Plectonotus. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 265-269 

derby!....................................................... 268 

salteri. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 268 

trilobatus.................................................... 266 

Plethocardia..................................................... 225 

Piethomytilus.............. ... .. . ... ... . . . . . . . . . . . . . . .. .. . ....... 212 

Plethorhyncha speciosa.......................................... 75 

Pleurodictyum problematicum .................................. 14, 331 

Pleuromya. .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 130 

Pleurophorella papillosa................. .. . . . . . . . . . . . . . . . . . . . . . . 236 

Pleurotomaria eloroidea.......................................... 277 

praJtexta. .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 277 

togata.... ... . . . . . . . . . . . .. . . . . . . . . . . .. . . . . . . . .. . . . .. . . . ... .. . . 277 

PleurotomariidaJ ............................................... 273-276 

Polypora lilaJa .................................................. 20,329 

lilia.......................................................... 20 

psyche ...................................................... 20,329 

Posidonomya becheri. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 206 

rhomboidea ............................................ .-... 194, 197 

Preavicula ..................................................... 205-208 

annulosa..................................................... 208 

brevis ................................................. .-.... 208,333 

elliptica...................................................... 208 

oblonga ........................................ 205,207-208,332, 333 

Prince, Harold W., ·collections by .............. : ...... :. . . . . . . . . . 5, 12 

Priondesmacea ................................................. 126-239 

Producti. ....................................................... ~ 27,45 

ProductidaJ ..•.............................................. ; .... 44-54 

Productus silcifer.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32 

sulcatus...................................................... · 32 

:Prolobella ........................ ·................................ 199 

Prolucina........................................................ 257 

Promyalina hindi. . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . 215 

Prosocoolus .......................................... ,........... 132 

Protomya......... .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 131 

Protremata ............. , ........................................ 25-63 

Pseudedmondia..................... ... . .. ... . . . . . ... .......... .. 141 

PseudomelaniidaJ ................... : .......................... 279-282 

Pseudotectus. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 276-279 

comes........................................................ 277 

deciduus.· ......................... : ................... : 278-279,317 

hitchcocki. ............................................ 277,278, 317 

sp. indet ................................................... 279,317 

Psilophyton princeps..... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 293 

Pteria ........................... :. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 178 

Pteriacea.... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 177-236 

PteriidaJ ................................. : . ............... .'. . . . 202-212 

Pterinea ........................................................ 177-178 

ampliata ............................................ ;........ 195 

cardiiformis ................................................ 198,199 

bisulcata..................................................... 128 

concentrica.................................................. 216 

condor ..................................................... 193,194 

corrects...................................................... 179 

costata ........................................ ·:·............. 178 

cuneata...................................................... 179 

demissa .................................................... 178,195 

edmundi........ ... . ... . .. . . . . . . . . . . . . . . . . . . . .. . . . . . .. . .... .. 187 

var. subrecta. .. . . . . . ... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 189 

fascicula ta. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 178, 190 

flabella....................................................... 178 

grandis... .................................................... 203 

hercyniaJ.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 203 

hians.. ... . ............................ .......... ............ 183 

intercostata .................................. ~ ............ :.. 205 

kerfornci. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 210 

laJvis ........................................... 177-178,194,195,209 

var. praJcursor........................................... 195 

lineata. .. . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 178 

lindstroemi ......... ~ . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 183 

mainensis .................... .' ......................... 178,179,191 

mytiloides ............................................. ~06, 207,208 
INDEX. 345 

Page_ S. Page. 

Pt<'rhtoa obsoquons ................................. · ·· .... ······· 179 Salter, J. W., on Ctenodonta. .... ............ .............. ... ... 157 

ostroiformis ............................. · · · · · .. · · · .. · · .. · · · 178,179 Sanguin.olaria ............................. ~ ............ : . ...... 130,133 

radlnlls ............................................. 178,179,182,184 conccntrica.......... .. .. .. . .. . .. .. .. . . .. . . . . . . . . . . . . . . . .. . .. . 144 

rotrofloxa ............................... · ...... · ........... · · 194 gibbosa·..... .............................................. ... 165 

vm·. {J •• •••••••••••••••••••••••••••••• • • • • • • • • • • • • • • • • • • • • 195 Sanguinolites................ . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 130, 133 

var. 'Y· .............................. · • · • · • .. · • • · • · • .. • ·.. 1!14 acuta .................................................... C:.... 225 

rhonlbopsla ..................... · · · · · · · · · · · · · · · · · · · · · · · · · · · · · 184 amygdalinus ....................................... ·.......... 143 

soworbyi......... ........................ ............ ........ 183 angulatus................... ...... .... .. .... .. ... ... .. ....... 230 

strlatocosta .................................... · · · · · · · · · · · · · · 1tl9 arcmformis.. .. . . .. .. .. .. .. . . .. . . . . . . . . . .. . . . . . . . . . . . . . . . . . .. . 235 

subplMa ................................ · · · · · · · · · · · · · · · · · · · · · 194 bipartitus.................................................... '230 

tcnulstrinta ............................... · ..... · · · · · · · · · · · · · 184 combensis....... ... . . . . .. . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . ·250 

vcn tricosn ....................................... · · · · · · · · · · · · · 178 constrictus............ .. .. .. .. . . . . . . . . . . . . . . . . . . . . . . . . . .. .. .. 230 

sp ....................................... · · · · · · · · · · · · · · · · · · · · · 194 cuneatus ...................... ~.............................. 230 

Ptorinoidro ................................... · · · · · · · · · · · · · · · · · · 177-201 decipiens ........................................... ~.. 254, 255,'256 

l'torlnopocten aroostook!.. ................... : ................. 187,189 gracilis....................................................... '250 

Ptoronltolla ............................................ 178,193-197,209 hamiltonensis................................................ 225 

comotula ................................................. · · 194,197 lyollianus .......................................... :......... ·230 

condor .......................................... · ...... 195, 196, 197 prmsectus ...... · ................................... :.......... 230 

curta ...................................... · ...... :.: ... 193, 195, 197 Scaphiocoolia boliviensis.......................................... · 75 

orocta ................................... · .... · · · · · · .. : .. · · · · · 197 Scenidium ....................................................... 61-63 

hlrundo...................................................... 195 devonlcum ....................... : ........................... 62,63 

nav.Jforn1o ................................ · · · .... · · .... · 195,196, 197 SchizocrMia discus............................................... 22 

oblonga ........................................ 193, 194, 195,196, 197 helderbergim ...................................... :.......... 25 

passer ........................................ -............... 195 Schizodus ............................................... ; ...... 238-'239 

peninsnlro .................................. · ·- .... ·. · ...... 184,195 orbicularis ................................................. 246,247 

quad rata ........................................... 195,196-197,330 prunum ................................................ 238-239,'327 

retrofloxn ...................................... 193,194,195,196,197 sp. indet .................................................... 239,331 

roctangulnrJs ............................. ·................... 197 Schizophoria impressa............................................ ' 58 

vonustn ........................................ 193,194,195,196,197 multistriata............ ... .. . . . .. .. . .. . . . .. . . . . .. . . . . .. . . . .. 58 

Pteronites.... ............. ....... .......... ...................... 178 Schuchert,·Charles, work or...................................... 6 

inoptatus ...... · ... · · · · ·. · · · · · · · · ·- · · · · ·. · · · · · · · · · · · · · ........ 195 Schuchertella .................................................... 34-41 

profundus ............................... · ........... '......... 195 agassizi. ..................................................... 38,39 

rostratus ..................... ·.·.............................. 195 bainii. ................ : ...................................... 38,39 

Ptoropodt\ ......... · · · .. · · · .. · .. · · · .... · · · .. · · · · · · .. · · · · · · · · · .. · 283-285 chemungensis....... . . . . . .. . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . .. . ' 39 

l'ton1atls.... .. . .. . . . .. . .. . . . .. . .. . . . . . .. . . . .. . . . . . . . . . .. . . . . . .. . . 264 crenistria.... .. .. .. . .. . . . .. .. . . .. . . . . . . . . .. . . . . . . . . . . . . . . .. . .. 39 

Ptychodosma.................................................... 147 deckerensis................................................... 41 

Jmappianum .................................... : .. 153-154,155,156 deformis ................................... : ........ : . ... 40-41,312 

minor ..... · .. · · · .. · .. · ...... · .... · · · · · · · · · · · · · · ·. · · .. · · · .... · : 155 desiderata .................. '· . . . .. . . . . . . . . . . . . . . . . . . . . . . .. .. . 39 

nnnutn....................................................... 155 devonicos.................................................... 41 

nllssoni ............................................ : . . . . . . . . . 154 hipponyx. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39 

Pull1nrosvtr1a

8

·o·l·l·ip. -t~~---: .' .' .' .' .' .' .' .' .' .' .' .' .' .' .' .' .' .' .' .' .' .' .' :.·.· .' .' .' .' .' .': .' .' .' .' :.·.·.· .' :.· .

2

•

40,2524, 5

7 pandora ...................................................... 38,39 

R. 

Rensselar.ria .......................................... : ........... 72-75 

atiMtica. . • . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 72 

crassicosta .................. •. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 75 

mninensis ........................................ 72-75, 123,310,316 

mutabilis. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 75 

ovoidos ....................................................... 18, 75 

strigicops ......................................... : . . . . . . . . . . . 298 

stringlcops. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 75 

Rotoporn sp. nov................................................. 20 

Rhipfdomolla lucia................................................ 57 

Rhomboptorfa................................................... 206. 

Rhynchonolln... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 67 

ainslie!....................................................... 66 

allogania. .. .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . .. . 63 

capax........................................................ 66 

don tatum... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 66 

dryopo .......................................... * ............ 64,65 

formosa ...................................................... 64,65 

inroqulvalvo.................................................. 66 

Inticostatun1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 66 

::!~~j~:::::::::::::::::::::::::::::::::::::::::::::::::::. 67, 3~~ ottnwacnso.................................................. 66 

paltunbinn................................................... 67 

porlnmollosum. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 66 

subtrigonalls................................................. 66 

Rhyncllonollidro ................................................. 63-75 

Uhyncllotromn formosum ..................................... 64, 65, 66 

Rhytimyn.. .. .. .. .. .. ......... .. .. . . . . . . . . . . . . . . . .. ........... .. 133 

Roonlorolln ...................................................... 21-24 

allogllMia .................................................... 23-24 

grandis......................................... .............. 22 

Rutotiaelliptica ............................................. :... 206 

subplanus.................................................... 38 

sulivMi ...................................................... 38,39 

umbraculum .... · ............................................. 38,39 

woolworthana ............................................ 34-39,306 

Sedgwickia ..................................................... 130, 133 

Serpulites longissimus ......................................... 17, 18,19 

Sinuitopsis neglecta var. transgrediens .. ; ..................... , . . 272 

Solen ambiguus ............. .'.................................... 253 

costatus ................................................... 250,252 

gladiolus.................................................... 253 

siliqua....................................................... 253 

Solenacea .... : ............................................. :: .. 249-257 

Solenidm ....................................................... 249-257 

Solenopsidm ............................ · ........................ 126-127 

Solenopsis belgica .......................................... 250,251,252 

Spa thelia ....................................................... 132, 140 

Specimens, miscellaneous, localities of............................ 13 

Sphenolium .................. ·. . . . .. .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 132 

Sphenomya ............................. ·: .. . . . . ... . . . . . . . . . . . . . . . 131 

Sphenotomorpha.. .. .. .. . . .. .. . . . .. . . .. . . . . . .. .. . . . . . . . . . . . . . . . 233-236 

rigidula ; .............................................. 234-236,331 

Sphenotus. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 132, 235 

arcmfortnis .. . . .. . . . .. . . . .. .. .. . .. . . . .. . . . . . . . . . . . . . . . . . . . . . . . 235 

bodenbenderi. ......................................... 234, 235-236 

contractus.... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 235 

ellsi.. .. . .. .. . .. . . . . .. .. . .. .. .. .. .. . . . . . . .. . . . . . . . . . . . . . . .. . 254, 256 

gorceixi. . .. . . . . . . . . . . . . . . . .. .. . . . . . . . . . . . . . . . . . . . . . . . . .. .. . .. 127 

solenoides .................................................. 127,235 

Spirifer .............................................. SG-114, 115,116-117 

antarcticus .................... 96, 97,99-100,101-102,103,104,107,111 

arenosa .......................................... _. .. · ......... 84,85 

arenosus ................ 31, 53, SO, 81, 83,84-86,87,91, 114,305, 306,308 

var. simplex .......................................... 86-88, 306 

arrectus .......................... 93, 95, 96, 97, 98, ~100, 101, 102, 103 

var. antarcticus ......................................... 9fi, 102 

var. hawkinsii.... ... . .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 96 

billingsa.na..... .. .. . . . . . .. . . . . .. .. .. .. .. .. . . . . .. . . . . . . . . .. . . . 85 
346 INDEX. 

Page. 

Bpir~~~~:!~~ ~ ~ .· .· ~ ." .· .· ." ~ _· _· .· ." _- ." ." .· ." ." ." ." ." ." ." ." _" _" _" ." ." _" _" _" _" ~ ~ _" _" _" _" ." ." _" ." ." ." .". ~o~~i6~ . bragensi<~ .... :. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ... . . . . . . . . . . 91 

buarquianus ........................................... :. . . . . 108 

var.alata ... : .......................................... 108,111 

var. contracts ..... : .................................... 108,111 

capensis .................................................. 99, 103, 104 

carinatus .......................... ·........................... 83 

chuquisaca ........................................... 99, 101, 102, 104 

concinna. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 80 

concinnoides . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 82 

concinnus .................. 80-84,88,89, 114, 298,303, 305,306,307, 308 

crispa.· ............................................... :. . . . . . . 92 

crispus.............. .. ... . .. .. . . . . . .. .. . .. .. .. . ........... .. • 92 

cultrijugatus ........................ :. . . . . . . . . . . . . . . . . . . . . . . . 35 

cumberlandiro... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 110, 113 

cumberlandica. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 96 

cuspidata. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . 76 

cycloptera .. · ............ : . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 88 

cycl~pt~rus- .......... 45, 82, 83,88-95,98, 100, 106,298,303,304,305, 307 

cymmdis ............................... : . . . . . . . . . . . . . . . . . . . . . 89 

var. sparsa. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 105 

daleidensis ............ ~ . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 86, 91 

derbyi. .. .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 97, 101 

divarlcata....... .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 86 

dunensis...... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 108 

duodenarius ................................ 1()(}-101, 102,104-105,307 

engelmanni ...•..... ~ ................................... 95, 101, 107 

excavatus ................................................. 80,82-83 

gaspensis.... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 96, 101, 107-113, 307 

granulosus ................. : ............................... 113, 114 

grleri. ............. ······-· .. . .. . .. . .. .. . .. ....... .. . . . ... .... 84 

hawkinsii. .......................................... 95, 101, 102, 107 

hemicyclus .............................. : ............... 92, 101, 107 

hercynire ........ ~ ........................ 51, 52,101,107,108,112,113 

var. primreviformis .................................... 108,.112 

hesione.... ... . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 106 

hystericus.. ................................................ 91, 93,94 

ilsre ........................................................ 106-107 

inchoans ......................... · . . . . . . . . . . . . . . . . . . . . . . . . . . . . 70 

n1acropleurus. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 106 

macropterus ............................................... 107,112 

macrotbyris ................ .- ........................ 97,101,110-111 

mercurii. .............................................. :. . . . . 93, 95 

montrealensis ................. · ..................... 113-114,303,305 

murchison! ..... , ............•...................... 31, 52, 89,90-91, 

92,93-94,95-104, 105, 106, 107, 110, 115, 117, 182, 303,304, 305 

murchisonianus.... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 95 

nerei........ ...... .. .. . . . . . . .. .. . . . ... . . . . .. ... .. . . . .. .. ..... 83 

nictauensis ..................................... .". . . . . . . . . . . . . 108 

octocostatus.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 92 

orbignyi. ............................... 99, 101, 102, 104, 108, 111-112 

owcni. ...................................................... , 114 

paradoxus ............................................. 107,108,112 

.mut. prrecursor. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 108 

var. hercynire ..... :. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 108 

pedroanus .............................................. 102, 108, 111 

perimele ............ ·. . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . . 109 

pbalrena.... .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . 108 

pollens....................................................... 107 

primrevus .................................... ~. . . . . 52, 86, 93, 94, 104 

atlantica . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 109 

prohystericus. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . 94 

quicbua........ ....... .......... ............ ................. 95 

quichuus ................................................... 101, 103 

raricosta ........ ·............................................. 105 

satfordi. . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . . . . 92 

sparsus ................................. 102,105-107,303,304,305,307 

subcuspidatus latemcisus ................................. 81, 82,83 

subhystericus................................................ 94 

submucronatus. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 110, 113 

subsulcatus.................................................. 91 

superba ...... : . .............................................. 84,85 

tribulus ...................................................... 92,93 

unica ...... :................................................. 84 

unicus... .......... ...... ... .... .... ......................... 85 

undulatus..... ........ .. .... . . . . . . . . .. .. . .. ... .. . .. . .. .. ... .. 106 

. vanuxemi. ..•••..•••.•............................. 70, 90, 91, 93,124 

Page. 

Spir!~~e~i~~~~~~~~--.... ."~." ."." ." ." ." ." ."." ." ."."." ." ." .... ." ." ." .": ::::::::.::::::::::::.96, ~~~ winterii.. . . . . . . . . . . . . .. . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . . . 84 

worthenanus ................................................ 96, 101 

sp. a .................................................... 96,101,103 

Spirifera arrccta.. . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 95, 96. 

buarquiana ................................................ 107,111 

concinna. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . so 

cycloptera ............................... :. . . . . . . . . . . . . . . . . . . . 88, 95 

derbyii.... .. . . . .. . ... .. . .. .. . . . . . . .. .. .............. .. . . ... . . 95 

duodenaria..... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 104 

gaspensis ................................................... 107, lOS 

nictauensis... . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . 107 

raricosta ................................................ 95,105,106 

sp. indet. .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 108 

Spiriferacea ..................................................... 76-118 

Spiriferidre ..................................................... 76-118 

~!::~~:~~=~~~~~~~~:::::::::::::::::::::::::::::::::::::::::::: ~~ dryope ....................... :. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 66 

formosa. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 63, 64-66, 310, 311 

streptorhyncbus agassizi......................................... 35 

cbemungensis..... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36 

deforlllis. . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . 40 

devonicus .................................................... 35,41 

~~~~;;~~~---_· _. .... :::::::: .... :::::: .. ::::::::::::::::::::::::::: !~ pandora ................................................... 34,35,36 

umbraculum ................................................. 35, 36 

woolworthana ................................................ 35, 36 

woolwortbanus ...................... ·......................... 36 

woolworthanum.... ......................................... . 36 

Streptotrocbus. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 277 

incisum. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 279 

Stringocephalus burtuni..... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 70 

Stropheodonta bipartita.... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29 

blainvillei.. . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . 28 

conqina. .. .......................... .. ....................... 29 

macrostriata ... : . . . . . . . . . . .. . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . 51 

magnifica.................................................... . 25 

~~:~~:~.- _.: .. :::::: .. :::::::::: .. ::::::::::::::::::::::::::: :":·: ~~:: textilis....................................................... 29 

tullia............................ ... . . .. . . . . . . . . . . . . . . . . . . . . . . . 28 

Strophodonta intermedia ................... , . . . . . . . . . . . . . . . . . . . . . 42 

nearpassi... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27, 28 

perplana .................................................. 27, 28,29 

planulata ...................... : ............................. 27, 28 

textilis ....................................................... 27,28 

woolworthana... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36 

Stropbomena analoga..... .. . ... ..... ... .. .. .. . . . . .. . . . . .. .. ... .. 32 

bainii. .. .. .. ...... .. . . . . .. ... .. . .. . .. . .. .. . . . . . .. . . . . ... . . .. . 34 

bipartita ......................................•.............. 27,28 

blainvillei. ................................................... 27,-28 

depressa ................................ _. . . . . . . . . . . . . . . . . . . . . 32 

expansa...................................................... 57 

gibbosa ...................................................... 32,54 

grandis...... .. ...... ... ... . . . . .. .. . . .. .. . .. . . . . . . . .. . . .. . ... . 57 

mucronata................................................... 49 

obovata......................... ............................. 34 

perplana ..................................................... 27,28 

pleuristriata.... . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27 

rhomboidalis ................................................. 32,33 

rugosa....................................................... 32 

sulivani ..................................... .-................ 34 

tenuistriata ................................................. : 32,33 

tullia.................... .. . . . . .. .. .. . . . . .. .. .. .. . . . . . . . . .. . . . 27 

undulata.... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32 

undnlatus........... .. .. .. . . . . .. . . .. .. .. . . .. .. . . . . .. . . .. ... . . · 32 

undulosa.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32 

unguiformis........ ... . . .. . .. . . . .. .. . . . . .. .. . .. . . . . . . . . . . . . . . 41 

woolworthana ...... , ......................................... 34,36 

sp............................................................ 27 

Strophomenacea ................................................. 25-63 

Strophomenidre .................................................. 25-44 

Strophostylus ................................................... 262,263 

globosus ................................................... 263,318 

Synphoria ................ · ......................... .-........... 288-289 
INDEX. 347 

T. Page. Page. 

Teloodesmacoa ................................................. 239-259 Trachyderma .................................................... 17-19 

'l'olllmyn ................ ·......................................... 158 cla.rkii. ................... · ................................... 18, 19 

1'o1Unn blcostula ............................................... 243,248 coriacea ...................................................... 17,19 

'.rollinomyn .................................................... 157-159 dcpressa ..................................................... 18,19 

nnsuta ................................. : ................... 157-159 serrata .......................... ·............................. 18 

soclalis....................................................... 175 speciosa.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19, 329 

'rolllnltos ....................................................... 163-167 squamosa ............ , .................................... 17, 18,19 

affinls ...................................................... 163,164 Trigeria ochlerti.. .......................................... 122, 123-124 

chapman! .......................................... 163-164,165,325 Trigoniacea .................................................... 238-239 

curta.... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 163,165, 332 Trigoniidm ..................................................... 238-239 

ologans ................................................. 163, 164, 165 Trilobita ....................................................... 285-289 

gibbosa................................................... .. . 163 Trochidm ...................................................... 276-279 

vnr.crn.'lsa ......................................... 165-167,332 Trochus nstra.liforinis ......... ·. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 277 

var. kayscri ................................ 165-167,325,326, 332 incisus ........ · ......................... , . . . . .. . . . . . . . . . . . . . . . . 279 

orbigny!.... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 163 lundgreni. ................................................. 277, 278 

urllonl!ormls ............................................... W3,167 Tropidocyclus gratiosus. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 270 

Tolllnopsls subornarglnata ...................................... 163, 167 

subornarginatus.............................................. 163 

rotula. .. ...... .. . . .. . . . .. . . . . . . . . . . . .. . . . . . . . .. . .. ... . .. . . . .. 270 

Tropidodiscus .......................... , . . . . . . . . . . . . . . . . . . . . . . . 269-272 

Tolotrornata ..................................................... 63-126 minim us var. Americanus .................................. 272,320 

Tomnodlscus..... .. . . . . . . . . . . . . . . . . . . .. . .. . . . . . . . . . . . ... . .. .. ... 270 obex ................................................... 270-271,320 

Tontnculitos. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 283-285 somerseti. .............. :. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 271-272, 320 

annulatus .................................................. 283,284 Tubicola ......................................................... 15-19 

olongatus ........................................... HI, 2S4-285, 320 Turritella obsoleta.. . . . . . . . .. . . . . . . . . . . . .. . .. . .. . . . . . . . . . . . . . . . . . . 273 

grand is. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . .. . . . . . 284 u. 

gyracant11us... .... ..... .. .. .. ........ .. ... ................ .. 284 

.ningnronsis. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 284 

omntus ........................................ :. . . . . . . . . . . . . 284 

Ulrich, E. 0., on Modiomorpha. .. . .. .. .. .. .. .. . . . . . . . . . . . . . . . . . . 218 

on pstracoda .............................................. : 289-293 

scnlarirormls. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 285 v. 

scnlaris ................................................. 283,284,285 Van Ingon, Gilbert, coll<~ctions made by.. . . .. .. .. . . . . . . . . . . . . . . . 12 

schlothoirnl ........................................ 283--284,285, 320 Vanuxemia .................................................... 147, 154 

Tontaculltldro .................................................. 283-285 Vermes .......................................................... 15-19 

Torobratuh\ bullata.............................................. 75 Vertebrata ..... ·.·................................................ 293 

poruviMa.................................................... 120 Vitulina pustulosa.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 115 

schlothoirnil.................................................. 64 Vlasta........................................................... 132 

strJglcops.................................................... 75 w. Torobratulro .................................................... 107,120 Whitella......................................................... 225 

Toi"obratulidm .. ·.. . . . . . . . . . . . . . . .. .. .. . . . . . . . . . . . . . . . . . . . .. . . . .. . 76 z. To.robratullnm. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 76 Zygobeyrichia ......................... · ........................ 290-293 

TJlostono fauna, corroll\tion o! tho Chapman fauna with ........ 295-299 apicalis .................. · .............................. 291,292, 334 

TlogMa chmnungonsis........................................... 204 devonica ............................................... 291-292,334 

Tolmaia .•........... .'....................... ... .. ............... 178 extrema ............................................ 291,292-293,334 

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