/ 

SHORTER CONTRIBUTIONS TO GENERAL GEOLOGY, 1920. 

THE FAUNA OF THE CANNONBALL MARINE MEMBER OF THE 

LANCE FORMATION. 

By TIMOTHY w. STANTON. 

INTRODUCTION. 

The Cannonball marine member of the Lance 

formation was first recognized as a distinct 

stratigraphic unit by E. Russell Lloyd, of the 

United States Geological Survey, in 1912, 

when he was mapping the Cannonball River 

lignite field, in Morton, Adams, and Hettinger 

counties, N. Dak. Lloyd's report on this 

field, published in 1914,1 contains a brief description .of the member with a map which 

shows its distribution in parts of Morton and 

Adams counties. A fuller description and 

discussion by Lloyd and C. J. Hares 2 soon 

followed, in which the member was mapped 

from Missouri River near Bismarck, N. Dak., 

southwestward to Grand River, S. Dak., and 

westward to longitude 103°, thus covering 

almost all its known area. A larger-scale rna p 

of the western part of this area in South 

Dakota, ba8ed on the same field work, was 

published in 1916.3 

The map herewith presented (fig. 1) is a 

copy of Lloyd and Hares's map, supplemented 

on the north by data from a manuscript map 

by E. T. Hancock, based on his field work of 

1914 in the Heart River drainage basin west 

of Mandan, which has also been used by M. R. 

Campbell. 4 The tentative northern boundary 

on Missouri River and east of it (represented 

by a broken line) is added from observations 

which I made in 1914 on trips from Mandan to 

t U.S. Geol. Survey Bull. 541, pp. 243-291, 1914. 2 The Cannonball marine member of the Lance formation of North and 

South Dakota and its bearing on the Lance-Laramie problem: Jour. 

Geology, vol. 23, pp. 523-547, 1915. 

a Winchester, D. E., Hares, C. J., Lloyd, E. R., and Parks, E. M., 

The lignite field of northwestern South Dakota: U. S. Geol. Survey 

Bull. 627, 1916. 

i Guidebook of the western United States, Part A, Northern Pacific 

Route: U. S. Geol. Survey Bull. 611, sheet 7, 1915. 

Stanton and from Bismarck to Washburnthe latter in company with E. T. Hancock. 

The most northern point at which I have collected the characteristic marine fauna of the 

Cannonball member is on the west bank of 

Missouri River 1 mile south of Price, in the 

southern part of T. 142 N., R. 81 W., but 

rocks of the same general character, mainly 

dark sandy shales, continue in the low outcrops along the river almost to Fort Clark and 

are especially well exposed near Washburn. 

It is interesting to note in this connection 

the variations in the boundary between Cretaceous and Tertiary-that is, between Fox Hills 

and Fort Union-on Missouri River, as shown 

on the general maps of this region published 

by F. V. Hayden. On the small maps pubished in 185 7 5 and 1858 the boundary crosses 

the Missouri at the mouth of Heart River. 

The map accompanying the report on the geology and natural history of the upper Missouri 

published in 1863 6 extends the Cretaceous 

almost up to the present site of Washburn, 

and the map in the "Final report of the United 

States geological survey of Nebraska," published in 1872, carries it to Fort Clark. All 

these localities are considerably north of the 

actual ~limits of the Fox Hills sandstone as 

now known. The mapping was based on collections of marine fossils which Hayden had 

obtained "near the mouth of Heart River" 

and "near Fort Clark," consisting of five species formerly assigned to the Fox Hills fauna 

but now known to have been derived from the 

Cannonball marine member of the Lance 

formation. 

o Acad. Nat. Sci. Philadelphia Proc., vol. 9, p. 109; vol. 10, p. 158. 

& Am. Philos. Soc. Trans., new ser., vol. 12, pp. 1-218, 1863. 

1 
s 

% 

2l 

EXPLANATION 

Scale 

ro o ro oo oo~~ 

Fort Union and White River(wR) formation 

Complied by E. Russell Lloyd and C. J. Hares, with added 

mapping by E. T. Hancock in Tps. 137 to 140 N., Rs. 82 LJ to 86 W., and reconnaissance mapping by T. W. Stantol" · Cannonball marine member of Lance formation 

along Missouri River north of Mandan 

Ludlow lignit1c member of Lance formation 

~ Lower part of Lance formation 

li~{/t:h}C~I Fox Hills sandstone 

Pierre shale 

..-: f' t <P'? / C L / ~ < ":5 ~d cr;t' •L / ( ~'_4 (W{' 

FIGURE I.-Geologic map of part of western North and South Dakota. 

82 81 80 

toO 

rJ2 

Ill 

t?;j 

~ p.; 

Q 

0 

~ 

H 

s 

0 

t-3 

1-4 

0 

~ rn 

t-3 

0 

&-3 

~ 

~ &-3 

0 

t"' 

0 

0 

._.1<1 

1-' 

~ 
FAUNA OF CANNONBALL MARINE MEMBER OF. LANCE FORMATION. 8 

Part of the area covered by the Cannonball 

marine member was mapped by A. G .. Leonard 

in the Bismarck folio, published in 1911, before the member was distinguished from the 

rest of the Lance formation. Leonard has 

also published two small-scale generalized maps 

of North Dakota,t on both of which the boundary between Lance and Fort Union is shown 

as crossing the Missouri a few miles below 

W ~hburn. In the later map Lloyd's mapping 

of the Cannonball member west of Missouri 

River is copied and its area is extended to the 

northern limits of the Lance formation as 

drawn on the earlier map, but it is not ~hown 

on the east side of the Missouri, although it 

has been mapped by Campbell 2 with an indefinite lower boundary in the neighborhood 

of Bismarck. Farther east its limits are usually obscured by the heavy mantle of drift. 

The Cannonball member is the latest marine 

deposit known in the Great Plains province 

and thus adds one more item to the record of 

the sea's advances and retreats which mark the 

diastrophic history of the region that includes 

the Great Plains and the Rocky Mountains. 

It is intimately associated with some . of the 

continental deposits which lie near the boundary between Cretaceous and Tertiary and concerning whose exact age there has been and 

still is difference of opinion. For these reasons 

it will be profitable to describe the fauna of the 

Cannonball marine member of the Lance formation, to illustrate it fully, to consider its relations to other faunas, and to discuss other 

facts that may have a bearing on the determination of its age. 

In the preparation of this paper I have 

studied all known collections of animal fossils 

from the Cannonball member. These consist 

of (1) types of supposed Fox Hills species described by Meek and Hayden from Heart River 

and the vicinity of Fort Clark; (2) collections 

obtained by E. Russell Lloyd and party during 

the field seasons of 1912 and 1913 in the area 

extending from the neighborhood of Lemmon, 

S.Dak., to Mandan, N.Dak., including fossils 

collected by Lloyd, Knowlton, Berry, and 

Stanton during a field conference covering part 

of this area in 1913; (3) collections obtained by 

C. J. Hares in the upper Grand River valley of 

1 The geological map of North Dakota: North Dakota Univ. Quart. 

Jour., vol. 4, p. 4, 1913; The geological history of North Dakota: Idem, 

vol. 7, p. 232, 1917. 

I U.S. Geol. Survey Bull. 611, sheet 7, 1915. 

North and South Dakota in 1912; (4) collections made by E. T. Hancock while mapping 

several townships west of Mandan in 1914·; (5) 

collections made by myself in 1914 in the 

neighborhood of Mandan, near Price on the 

Missouri, 19 . miles north of Mandan, and near 

Solen on Cannonball River. 

STRATIGRAPIDC RELATIONS. 

GENERAL SECTION. 

The stratigraphic relations, lithology, and 

detailed stratigraphy of the Lance formation 

in western North and South Dakota have been 

well presented by Lloyd and Hares,3 from whose 

paper copious quotations are 'made below, including the table and detailed sections. 

In a large region west of Missouri River in North and 

South Dakota the Lance formation consists of two distinct 

parts-a lower nonmarine part containing a flora. very 

similar to if not identical with that of the Fort Union, and 

an upper marine member containing a fauna closely resembling but not identical with that of the Fox Hill sandstone. This upper part, on account of its pecul.iar fauna, 

has been mapped separately and named the Oanrionball 

marine member of the Lance formation. Faither west 

nonmarine· beds bearing lignite and occupying a similar 

stratigraphic position have been named the Ludlow lignitic 

member of the Lance. 

T~e general character and relations of the Cretaceous 

and Tertiary formations exposed in this part of the Dakotas 

are shown in Table 1. The areal distribution is shown on 

the map (fig. 1). 

CRETACEOUS SYSTEM:. 

PIERRE SHALE. 

The oldest formation exposed in the area 

covered by the map is the well-known and 

widely distributed Pierre shale, the upper part 

(about 300 feet) of which is seen in the valleys 

of the Missouri and Grand rivers, in the southeast corner of the area, and on the Little 

Missouri near the western margin. It is a 

dark-gray marine shale with a characteristic 

Upper Cretaceous fauna, including Inoceramus 

barabini, Baculites ovatus, B. compressus, Placenticeras whitjieldi, Scaphites nodo8U8, and 

many others. It is worthy of note., however, 

that the upper 200 feet of Pierre shale as 

mapped in Missouri and Grand river valleys 

does not contain the species just mentioned 

but is characterized by a Fox Hills fauna, including Sphenodiscus lenticularis, Scaphites 

conradi, and several related species of Scaphites 

with many species of littoral pelecypods and 

gastropods. (See partial list on p. 4.) 

a Jour. Geology, vol. 23, pp. 523-547, 1915. 
4 SHORTER CONTRIBUTIONS TO GENERAL GEOLOGY, 1920. 

TABLE I.-Cretaceous and Tertiary formations in western North and South Dakota. 

System. Series. Formation. Character. Thickness 

in feet. 

-

Oligocene. White River. Cross-bedded sandstone and fresh-water limestone •.••••...•...•...............•....... 140 

Tertiary. Unconformity, angular up to 20° and erosional up to 1,500 feet. 

Eocene. Fort Union. Yellow sandstone, shale, clay, and lignite ...... 1,025 

Cannonball marine member. Dark sandy shale 

dark ~h!l-lY lim~stone, and yellow sandstone: 

contammg manne shells ......••••..••..•... 0-300 

Tertiary? Eocene? Lance. Ludlow lignitic member. Light sandy shale 

calcareous sandstone and lignite .....••••.. :. 0-350 

Somber-colored shale, yellow sandstone and 

thin lignite beds ..•............•.•••• '•..... 400--525 

Fox Hills. Sandstone, yellow ............................ 25-400 

Cretaceous. Upper Cretaceous. 

Pierre. Dark marine shale ............... ................... 300+ 

FOX HILLS SANDSTONE. 

The Fox Hills sandstone of the eastern part 

of the area mapped is continuous with the 

typical exposures of the formation in Fox 

Ridge between Moreau and Cheyenne rivers, 

S. Dak .. It is made up of gray, yellow, and 

buff sandstone, locally in two or more distinct 

beds, separated by banded shale. The whole 

formation has ·a maximum thickness of about 

150 feet in the Standing Rock and Cheyenne 

River Indian reservations, but in some localities its thickness is apparently reduced to 25 

feet or less. This variation in thickness has 

been attributed by Knowlton/ Calvert/ and 

others to removal of the upper part of the formation by erosion before the overlying Lance 

formation was laid down. This opinion is 

supported by direct evidence of local erosion 

in many places at or near the top of the Fox 

Hills sandstone, but I have shown in a previous 

paper 8 that the eroded surface at many localities in this area is within the Fox Hills sand1 Knowlton, F. H., Further data on the stratigraphic position of the 

Lance formation(" Ceratflp8 beds"): Jour. Geology, vol. 19, pp. 362-371, 

1911; Cretaceous-Tertiary boundary in the Rocky Mountain region: 

Geol. .Soc. America Bull, vol. 25, pp. 326-327,1914. 2 Calvert, W. R., Beekly, A. L., Barnett, V. H., and Pishel, M.A., 

Geology of the Standing Rock and Cheyenne River Indian reservations: 

U. 8. Geol. Survey Bull. 575, pp. 18-20, 1914. 

a Stanton, T. W., Fox HillssandstoneandLanceformation (" Ceratops 

beds") in South Dakota, North Dakota, and eastern Wyoming: Am. 

Jour. Sci., 4th ser., vol. 30, pp. 173-182, 1910. 

stone and not above it, for the reason that the 

bed immediately above the irregular surface 

contains along with a brackish-water fauna 

several forms of Scaphites and other marine 

Cretaceous invertebrates characteristic of the 

Fox Hills fauna. Evidence was also given in 

this paper that the whole Fox Hills sandstone 

is the product of very irregular deposition such 

as must occur in the shallowing waters of a 

retreating sea. The variation in apparent 

thickness is due in part to the fact that the 

base of the sandstone varies in position because 

sands and shales were simultaneously deposited 

in neighboring localities. 

The most common and characteristic species 

of the Fox Hills marine fauna are as follows: 

Pteria linguaeformis Evans and Shumard. 

Pteria nebrascana Evans and Shumard. 

Cucullaea shumardi Meek and Hayden. 

Limopsis striatopunctata Evans and Shumard. 

Leda (Yoldia) evansi Meek and Hayden. 

Nucula cancellata Meek and Hayden. 

N ucula planimarginata Meek and Hayden. 

Lucina occidentalis (Morton). 

Tancredia americana Meek and Hayden. 

Protocardia subquadrata Evans and Shumard. 

Callista deweyi Meek and Hayden. 

Tellina scitula Meek and Hayden. 

Mactra warrenana Meek and Hayden. 

Cuspidaria ventricosa (Meek and Hayden). 

Lunatia occidentalis Meek and Hayden. 

Lunatia concinna Hall and Meek. 
FAUNA OF CANNONBALL MARINE MEMBER OF LANCE FORMATION. 5 

Lunatia subcrassa Meek and Hayden. 

Anchura (Drepanochilus). americana (Evans and 

Shumard). 

Pyropsis bairdi Meek and Hayden. 

Fasciolaria (Piestochilus) culbertsoni Meek and 

Hayden. 

:rasciolaria buccinoides Meek and Hayden. 

P~fusus newbenyi Meek and Hayden. 

Fus~ (Serrifusus) dakotensis Meek and Hayden. 

Cylichna volvaria Meek and Hayden. 

Hamine~:~. minor.Meek and Hayden. 

Cinulia co:B.cinna Meek and Hayden. 

Sphenodiscualenticularis (Owen). 

Scaphites conradi (Morton). 

Scaphites conradi var. intermedius Meek. 

Scaphites abyssinus (Morton). 

Scaphites nicolleti (Morton). 

Scaphites cheyennensis (Owen). 

The upper 200 feet of the Pierre shale as 

mapped along Missouri River and its tributaries in South Dakota contains the same fauna. 

In addition to this purely marine fauna there 

is the brackish-water fauna already mentioned, 

which at some localities contains an admixture 

of marine forms. It is found at the top of the 

Fox Hills sandstone in an irregular bed that 

has been assigned by some geologists to the 

overlying Lance formation, on account of the 

evidence of erosion at its base. I have considered it the topmost member of the Fox Hills 

sandstone, because its marine fossils are mostly 

characteristic Fox Hills species, and have attributed its irregular ·base and other irregularities 

to the action of tidal currents; but whether it 

is assigned to the one formation or the other, 

the character of its fauna is proof of a· gradual 

transition from marine to nonmarine conditions, the record of ·which would not have been 

retained if there had been a long period of erosion after the retreat of the Fox Hills sea. 

This brackish-water fauna with its associated 

marine forms includes the species named in the 

following list, in which * indicates marine 

species, t species that occur also in the Cannon- I 

ball marine member of the Lance and in older 1 

formations, and t species that occur also in the 

Ludlow lignitic member of the Lance and In 

older formations. 

tOstrea subtrigonalis Evans and Shumard. 

tOstrea glabra Meek and Hayden. 

Anomia micronema Meek. 

Modiola meeki (Evans and Shumard)? 

Corbicula occidentalis Meek and Hayden. 

Corbicula nebra8censis Meek and Hayden. 

tCorbicula cytherlformis Meek and Hayden. 

Corbicula subelliptica var. moreauensis Meek and 

Hayden. 

*Tancredia americana Meek and Hayden. 

*Tancredia? sp. 

tPanope simulatrix Whiteaves? 

Teredo sp. 

N eritina bruneri White. 

Neritina (Velatella) baptista White. 

Melania insculpta Meek. 

Melania wyomingensis Meek. 

*Lunatia obliquata Hall and Meek. 

t*Lunatia subcrassa Meek and Hayden. 

Melampus sp. 

*Scaphites conradi (Morton). 

*Scaphites conradi var. intermedius Meek. 

*Scaphites cheyennensis (Owen). 

This fauna through its marine element is 

directly connected with the Fox Hills fauna and 

through its brackiah-water element tends to 

connect a brackish-water facies of the Cannonball fauna with the brackish-water faunas of 

the Laramie, Mesaverde, Judith River, and 

other Cretaceous formations. In the course of 

the survey of the Standing Rock and Cheyenne 

River Indian reservations it was collected at 14 

localities and observed at many others scattered over an area extending 7 5 miles from 

north to south and 60 miles from east to west, 

as shown by the following list, in which localities yielding marine species mixed with the 

predominant brackish-water forms are indicated by t: 

tSec. 25, T. 11 N., R. 18 E., S.Dak. 

Sec. 18, T. 13 N., R. 18 E., S.Dak. 

tSec. 2, T. 13 N., R.19 E., S.Dak. 

Sec. 12, T. 13 N., R. 19 E., S.Dak. 

Sec. 6, T. 14 N., R. 18 E., S.Dak. 

tSec. 27, T. 14 N ., R. 19 E., S. Dak. 

Sec. 27, T. 14 N.; R. 20 E., S. Dak. 

Sec. 19, T. 14 N., R. 20 E., S.Dak. 

tSec. 12, T.15 N., R.18 E., S.Dak. 

tSec. 18, T. 17 N., R. 26 E., S.Dak. 

Sec. 12, T. 20 N ., R. 22 E., S. Dak. 

Sec. 27, T. 22 N., R. 24 E., S.Dak. 

Sec. 15, T. 22 N., R. 25 E., S.Dak. 

Sec. 20, T. 130 N., R. 80 W., N.Dak. 

The Cretaceous age of the Fox Hills sand 

stone is unquestioned, and the doubt as to its 

exact top involves only the few feet of beds 

containing the brackish-water fauna. Those 

who refer the brackish-water deposits to the 

overlying formation have suggested that· .the 

Scaphites and other characteristic Fox Hills 

species locally found in it were eroded from the 

underlying sandstone and redeposited, but it 

seems to me, after field examination of sev~ 
6 SHORTER CONTRIBUTIONS TO GENERAL GEOLOGY, 1920. 

eral of the localities, much more probable that 

they were carried by the tide up short inlets 

that were normally inhabited by brackishwater creatures only. 

TERTIARY ( 1) SYSTEM. 

LANCE FORMATION. 

The overlying rocks referred to the Lance 

formation are now classified by the United 

States Geological Survey as of Tertiary ( n 

age, but it is my opinion that they are Cretaceous. The following description is quoted 

from Lloyd and Hares: 1 

LOWER PART. 

It has been previously stated that the Lance formation 

in this region consists of three parts-a lo'\\ er group of 

shale and sandstone beds of continental origin and two 

contemporaneous upper members, one of sandstone and 

shale of marine origin, the other of sandstone, shale, and 

lignite of nonmarine origin. The lower part of the formation outcrops in a wide belt of country in Morton County, 

N. Dak. Northward it pas.<:es below the flood plain of 

Missouri River a few miles below Bismarck, and to the 

west it has been mapped to and beyond the MontanaDakota State line. It occupies a large area in Bowman 

and Billings counties, in southwest North Dakota, and in 

adjacent parts of Montana. Throughout this whole region 

it is essentially unHorm in character, consisting predominantly of somber-colored arenaceous shale intercalated 

with lenticular beds of brown or buff sandstone. Beds of 

brown carbonaceous shale, bog iron ore, and thin lignite 

a:re conspicuous in most outcrops. All the strata of the 

lower part of the Lance are lenticular in character, and a 

section exposed at one locality is different in most of 

its details from one even a short distance away. Crossbedding is common, especially in the sandstone. Irregularity of deposition is characteristic. Near Solen on Cannonball River, 9 miles above its inouth, the lower part cf 

the Lance bas a thickness of approximately 400 feet and 

on Little Missouri a thickness of about 525 feet. 

The fossils found in the lower part of the Lance in the 

western Dakotas consist of plant impressions and bones of 

reptiles. The plant remains are not abundant, but a few 

good collections have been made from widely separated 

localities. All of the species belong to the widespread 

Fort Union :f:lora. 2 The vertebrates include turtles and 

several genera of dinosaurs, 1 among which is the largehorned Triceratops, which is diagnostic of the Lance 

formation. The ceratopsian remains are especially abun-

.dan tnear the base of the formation in the Standing Rock 

Indian Reservation, but. on Little Missouri River several 

specimens of Triceratops have been found near the top of 

the formation and stratigraphically below the Ostrea glabra 

zone. 

1 Tour. Geology, vol. 23, pp. 527-5.'17, 1!115. 

2 For lists of plants and vertebrates coilected in the Standing Rock 

and Cheyenne River Indian reservations see U. s. Gcol. Survey Rnll. 

575, pp. 21, 22, 1914.-T. W. S. 

LUDLOW LIGNITIC liiEIIBEB.. 

The Ludlow lignitic member of the Lance formation 

occupies a large area in Harding County, S.Dak., and ea.!:!1-

ward into Perkins County, S. Dak., where it merges with 

the Cannonball marine memher. In the vicinity ofJudlow, S. Dak., its type locality, it consists of ~50 ~et of 

loosely consolidated buff and cream-colored cakareous 

sandstone and shale with interbedded lignite. · It contains most of the lignite of South Dakota, and t}le presence 

of this lignite is one of the chief criteria for cunsideringit a 

distinct member of the Lance formation- Its lithologic 

character jn South Dakota is very like And its fossil flora 

so far as determined is identical with· the Fort Union. 

Its flora is like that of the lower part of the Lance, but its 

lithology.is quite different. On the other hand, in North 

Dakota its flora has the same affinities as in South Dakota, 

but lithologically it resembles the lower part of the Lance, 

except for the presence of the numerous lignite beds. It 

is this variation in color and lithology of the Lance that 

renders its separation from the overlying Fort Union so 

difficult. 

The following sections show the lithologic character of 

the Ludlow lignitic member: 

Composite section in sees. 32 and 36, T. 22 N., R. 5 E. 

Black Hills meridian, 8. Dale. · 

Fort Union formation: Ft. in. 

Sandstone, yellowish, and shale .......... __ . 255 0 

Ludlo~ l~gnitic member of the Lance formation: 

Lignite ....................... __ ._.......... 8 

Sandstone, somewhat shaly.. .. . . . . . . . . . . . . . 45 0 

Shale, dark ..................... _ . _ .. _ .. _ . . 2 0 

Lignite ..................... _ .. _ ... __ . _... 2 4 

Sandstone, light colored, grayish, argillaceous 12 0 

S~nd.stone, buff, with ferruginous specks. . . . 15 0 

L1gmte. ................................... 2 

Sandstone, buff, fine grained, muscovitic... 11 0 

Lignite ................................ _.. 3 

Sandstone................................. 8 0 

Lignite ................ _.................... 6 

Sandstone, buff. . . . . . . . . . . . . . . . . . . . . . . . . . . 25 0 

Shale, bluish... . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 0 

Shale, carbonaceous ........ .' ..... _......... 10 

Shale, arenaceous ...................... _... 5 0 

Lignite ..................... _ .... _. _. . . . . . 1 

Sandstone, buff, soft ............. _.......... 5 4 

Sandstone .... _ .............. _ . _ .. _ . _ . . . . . . 1 0 

Shale, arenaceous with carbo:q.aceous streaks. 4. 0 

Sandstone, argillaceous ........... ___ ...... 6 0 

Lignite ..................... __ ... _ .... _ .. _ 1 0 

Concealed intervaL ........... _ ....... _.... 22 0 

Sandstone, drab, cross-bedded, ripple-marked 3 0 

Shale, arenaceous ................... _ . _ . . . . 4 0 

Lignite. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 5 

Shale, brown ...•.................... ·. . . . . . 3 0 

Lignite. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 1 

Shale, dark ................... _. _ ... _ .. ___ . 5 

Lignite ............................. ·...... 8 

Shale __ ........................... __ ..... _ . 1 3 

Lignite................................... 1 5 

Shale, brown.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 0 

Lignite ...••................ ·......•..••••• 2 3 

446 8 
FAUNA OF CANNONBALL MARINE MEMBER OF LANCE FORMATION. 7 

Section on west side of Little Missouri River, sec. 10, T. Ludlow lignitic member of the Lance formation: Ft. in. 

135 N., R. 105 W., N.Dak. 3. Lignite................................... 2 0 

0 

0 · Fort Union formation: 

, Sandstone, light ........................ .. 

Ludlow lignitic member of Lance formation: 

'~hale, dark ............................... . 

Hmestone, arenaceous .................... . 

Sh&l«;!, blue ..................... -.-.----.-

Sand~tone, gray, friable .................... . 

Shale, gray ............................... . 

Sandston~, argillaceous .................. .. 

S~l~, drab, hard ......................... . 

Lignite ................................. · .. 

Shale, dark, hard ......................... . 

S~al~, light, fossils, l~aves ................. . 

Lignite .................................. . 

Shale, carbonaceous ....................... . 

Sandstone ................................ . 

Shale ....••.•.............................. 

Sandstone and shale, alternately ............ . 

Lignite ................... · ............... . 

Sandstone and shale ....................... . 

Lignite .................................. . 

Sandstone ................................ . 

Lignite ............•...................... 

Sandstone, white, hard ................... . 

Sandstone in upper part, shale in lower part; 

Ostrea glabra above base (only representative found of Cannonball marine member). 

Lignite ................•.................. 

Sandstone and shale, sandstone in upper part 

and shale below .........•.....•.•.•...... 

Lignite ..............•.................... 

Shale ..................................... . 

Lignite ................................... . 

Shale ..................................... . 

S~nd.stone, hard ledge in upper part ...... . 

Lignite .................................. . 

Shale ..................................... . 

Lignite .................................. . 

Shale ..................................... . 

Lignite ..•................................ 

Shale .. · ................................... . 

Lignite .................................. . 

Shale ......•............................... 

Lignite .................................. . 

Shale ....••...... _ ........................ . 

Lignite .................................... . 

Sandstone .............. ~ ................. . 

Shale. 

Ft. in. 

15 2 

24 0 

2 10 

7 2 

4 0 

3 7 

1 4 

1 2 

4 5 

2 10 

2 10 

2 6 

1 8 

2 8 

1 8 

2 8 

1 0 

3 0 

6 

4 0 

1 7 

3 0 

33 11 

1 11 

27 0 

10 

11 0 

3 0 

3 4 

13 2 

5 3 

1 8 

1 2 

1 4 

5 0 

8 6 

6 11 

4 8 

6 

7 6 

5 4 

15 4 

250 11 

Section along North Fork of Grand River at Bloom, S. Dak. 

Fort Union formation(?): 

1. Sandstone, brown and yellow, fine grained, 

thin bedded, interbedded with lenses of 

compact bluish-gray limestone. 

Cannonball marine member of the Lance formation: 

2. Sandstone, dark gray, very calcareous; marine fossils Nucula planimarginata, Cal4. Shale and sandstone, interbedded. . . . . . . • 40 

5. Lignite........... . . . . . . . . . . . . . . . . . . . . . • • . 1 

53 0 

NOTE.-No. 1 was considered as Fort Union but veiy 

possibly is Cannonball, as indicated by more recent field 

work in other parts of the field. 

Generalized section along North Fork of Grand River between 

Bloom, S. Dak., and Haley, N. Dak.2 

Ft. in. 

1. Sandstone, brown and yellow, fine grained, thin 

bedded, and lenses of limestone .........•... 30. 0 

2. Sandstone, marine; burrows of Teredo selliformis, 

Anchura americana var. pusilla. . . • • • • • . . . . . . 10 

3. Shale....................................... 1 

4. Lignite........... . . . . . . . . . • . . . . . . . . . . . . . . . . . . 2 

5. Shale and sandstone, interbedded. Sandstone 

in lower part light brown, medium fine grained, 

micaceous, containing Halymenites major, Anatina subgracilis, Nucula subplana, Callista (Dosiniopsis) deweyi, Pholadomya haresi, imprints 

of pelecypods, and shark teeth .............. 40 

6. Lignite........... . . . . . . . . . . . . . . . . . . . • . . . . . . . . 1 

7. Shale........................................ 4 

8. Lignite....................................... 2 

9. Shale. 

90 

0 

0 

0 

0 

0 

0 

3 

3 

NoTE.-No. 1 was considered Fort Union ·but may be 

Cannonball; No.2 and part of No.5 are marine, and Nos. 

3, 4, 6, 7, 8, and 9 are considered fresh-water. 

CANNONBALL MARINE KEli(BE:S.. 

The Cannonball marine member of the Lance formation 

has been traced and mapped in an area. extending from 

near Mandan, N. Dak., to the vicinity of Ralph post office 

in Harding County, S.Dak., and 4 miles west of Haley, 

Bowman County, N. Dak. The presence of brackishwater fossils, Ostrea glabra, near Yule, on Little Missouri 

River in Billings County, N. Dak., shows that the sea 

probably extended some distance farther to the west than 

its sediments have been mapped. The extent of this 

member east of Missouri River is unknown. 

The marine member is composed predominantly of 

dark sandy shale or shaly sandstone with a subordinate 

amount of dark-yellow and gray sandstone. It also contains some thin limestones. All the strata are lenticular 

in character, and individual beds can be followed for only 

short distances. The member is typically exposed in the 

bluffs of Cannonball River in Tps. 132 and 133 N., Rs. 87 

and 88 W. The following sections measured in the type 

area. show the character of the strata of the Cannonball 

marine member and of the strata which underlie and lista (Dosiniopsis) deweyi, Pholadomya 

haresi, Corbula sp., Anchura americana var. Ft. 

pusilla 1 ••••••••••••••••••••••••••••••• 10 ~ overlie it: 

1 Names of fossils in all the quoted sections are revised in accordance 2 The last three sectiom expose the interrelations of the Ludlow Iignitic 

with nomenclature adopted in this paper. -T. W. S. and Cannonball marina membeiT. · 
8 SHORTER CONTRIBUTIONS TO GENERAL GEOLOGY, 1920. 

Section near base of the Cannonball marine member in south Section of lower part of Fort Union ftmnation and upper 

bluff of Cannonball River, sec. 33, T.132 N., R. 87 W. part of Cannonball marine member of Lanceformation in 

1. Sandstone and sandy shale, yellowish gray ..... Ft. in. south bluff of Cannonball River, sees. 31 and 32, T. 133 

23 0 N., R. 88 W. 

2. Sandstone, yellowish gray, unconsolidated, 

with thin lenses of shale near the bottom, 

containing poorly preserved leaf impressions. 22 

3. Shale, brown, sandy. . . . . . . . . . . . . . . . . . . . . . . . 22 

4. Shale, bluish brown. . . . . . . . . . . . . . . . . . . . . . . . . 2 

5. Lignite ..................................... . 

6. Shale, bluish brown ........................ . 

7. Sandstone, gray, unconsolidated ............. . 

8. Concealed to river level. ................... . 

4 

45+ 

15 

133+ 

Ft. fl1. 

Sandstone, yellow; upperpartmMSive, lowerpart 

0 thin bedded and near base interbedded with 

0 thin bands of gray shale. . . . . . . . . . . . . . . . . . . . . .SO 

0 Sandstone, dark gray to black.................. 3 

4 Sandstone, yellow, thin bedded, interbedded 

0 with gray shale .......................... , . . . 13 

Sandstone, gray, concretionary ................ . 

0 Shale, bluish gray and somber, sandy. . . . . . . . . . . 52 

Shale, dark gray. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 54 

Sandstone, yellowish gray, unconsolidated...... 5 

6 

6 

0 

6 

0 

In this section no definite line could be drawn between 

the lower part of the Lance and the Cannonball member. 

No.1 and probably No.2 belong to the marine member. 

Sandstone, yellow, hard at top, containing Lunatia obliquata, Turris cincta, Turris (Surcula) 

bacata, Fa..'lciolaria lloydi, Pyrifusus sp., and an 

undescribed coraL .......................... . 6 0 

Section in south bluff of Cannonball River about three-fourths Shale, sandy, dark gray, grading at top into sandof a mile west of foregoing section. stone....................................... 31 6 

Ft. in. 

1. Sandstone, yellow. . . . . . . . . . . . . . . . . . . . . . . . . . . 25 

2. Shale, containing poorly preserved plant remains...................................... 4 

3. Sandstone, gray •............................. 

29 

0 197 

The upper sandstone of this section probably belongs to 

0 the Fort Union formation and the remainder to the Cannonball member of the Lance formation. 

0 Sections similar in general character to those given 

The sandstone No. 1 in this section appears to be unconformable on the shale. It is probably the lowest bed of 

the Cannonball member. 

above are exposed in the bluffs of Heart River 1 and on 

Cedar Creek. The general appearance of the more sandy 

rocks is very much like that of the Fox Hills sandstone. 

The shale is very much like the Pierre. 

Section in bluffs of Cannonball River near Janesburg, N. A peculiar feature of both the Fox Hills sandstone and 

the Cannonball member of the Lance is the abundance 

Ft. in. of round concretions commonly known as "cannonballs." Dak., T. 132 N., R. 88 W. 

1. Sandstone, fine grained, containing "cannonball" concretions .................... . 

2. Shale, dark, sandy ......................... . 40+ 

10 

3. Sandstone and sandy shale, light colored, 

with ''cannonball" concretions........... 21 

4. Shale, dark, sandy, with Pedalion llvydi..... 4 

5. Sandstone and shale, light colored, thin 

bedded; the shale containing indeterminable vegetable remains...... . . . . . . . . . . . . . . 30 

6. Sandstone, consolidated.................... 1 

7. Shale, light blue .......................... . 1 

8. Sandstone and shale, alternating........ . . . . 15 

9. Shale, dark, carbonaceous................... 1 

10. Sandstone and shale, alternating; base concealed by talus at base of slope .......... . 

They are formed by cementation of the sandy shale by 

the deposition of calcium carbonate. These are true 

0 septarian nodules with radiating and concentric veins of 

calcite. The best examples observed are in a railway 

6 cutafewmileswestofRaleigh, N.Dak. Where the "can0 non balls" are exposed by stream erosion they are mostly 

weathered and broken to pieces. 

The rocks of the Cannonball member weather typically 

0 into rounded hills, and in the interstream areas natural 

6 rock exposures are very few. In a large part of the area 

6 where the member was examined in South Dakota the 

0 only evidences that the beds are of marine origin are a 

0 few thin beds of nodular fossilifero:us limestone, the presence 

of which is shown by the lines of reSidual boulders at the 

borders of level-topped hills. The topography is such, 

129+ 

No. 4 and the overlying beds of this section are undoubtedly of marine origin; the lowest beds may be nonmarine, 

but no definite line could be drawn. 

however, that these horizons can be followed for long distances. No definite line could be drawn in the field 

between the Cannonball marine member and the lower 

part of the Lance. The contact of the two groups of strata 

is exposed at only a few places, and in all such cases it 

seems to be impossible to tell where the beds of nonmarine 

o:igin stop and those of marine origin begin. It follows 

from the foregoing statement that there is no evidence 

of unconformity at this horizon. 

Section of part of Cannonball marine member in south bluffs 

of Cannonball River, E.! sec. 5, T. 132 N., R. 88 W. 

Ft. in. 

Shale, sandy, black, and brown, with Pyrijusus 

newberryi (?), fragments of Crassitellites, and a 

coral belonging to an undetermined genus... . . 16 

Sandstone, yellow, largely consolidated but with 

lenticular concretions of hard sandstone....... 31 

Shale, sandy, dark gray, nearly black.......... 52 

100 

The relationship of the Cannonball member with the 

6 underlying lower part of the Lance is well shown in the 

region northwest of Solen on Cannonball River, N. Dak. 

6 In this area the characteristic chaos of badlands formed by 

0 

1 For details or some of these sections see U. S. Geol. Survey Geol. 

0 Atlas, Bismarck folio (No. 181), p. 3, 1912.-T. W. S. 

/ 
FAUNA -OF CANNONBALL MARINE MEMBER OF LANCE FORMATION. 9 

the erosion of the- sandstone and shale of the lower part similar bones do not occur therein up through a stratiof the Lance is bordered on the north by a high, nearly graphic distance of perhaps 500 feet.'' 2 The T Croas 

level plateau which is capped by the lower fossiliferous lignite bed was mapped to the Montana State line, and 

saudstone of the Cannonball member. The top of the it is undoubtedly the same lignite as the "persistent 

plateau is approximately 500 feet above and only about lignite" referred to above. 

2miles distant from the river. The characteristic badland- The presence of numerous lignite beds in the upper part 

forming strata of the lower part of the_ Lance extend up of the Ladlow lignitic member of the Lance is in strong, 

to within about 100 feet of the top of the plateau, but here, contrast to the undifferentiated lower part of the formaas elsewhere, no sharp line of demarkation can be drawn. tion, and the absence of marine fossils in this member is in 

contrast to the Cannonball marine member. The Ludlow 

Lloyd and Hares make this additional state- lignitic and. the Cannonball marine members are considment about the interrelationships of the Lud- ered to be contemporaneous in age. 

low lignitic member .and the Cannonball marine It is evident from the above description that 

member of the Lance formation: the Cannonball marine member rapidly thins 

It has been shown that the Lance formation in a large toward the west until it is reduced to one or 

region immediately west of Missouri River consists of two thin beds which .extend as tongues into 

two parts, the upper of which, the Cannonball member, the predominantly continental deposits of the 

is marine and contains a fauna similar to but not identical 

with that of the Fox Hills sandstone. The Cannonball Ludlow lignitic member, and although the 

member becomes gradually thinner toward the west, and exposures are not sufficient to show the conthe sea in which it was deposited perhaps did not extend. nection it is reasonably certain that one of 

as far west as the Montana line. The oyster beds near these tongues is directly connected with the 

Yule in Billings County, N. Dale, first discovered by oyster bed near Yule, on the Little Missouri, Leonard and later described by Stanton, 1 may represent 

the westernmost limit to which the Cannonball sea ex- which must represent a brackish-water estuary 

tended. This region was studied in 1911, and it was found or inlet at the western margin of the Cannonball 

by Hares that the beds containing the oysters are about sea. 

700 feet above the base of the Lance. 

The zone in which Ostrea glabra and Ostrea subtrigonalis 

occur, in Tps. 135 and 134 N ., R. 105 W., is considered 

the westward extension (so far as known at present) of 

the strata of marine origin, as the oysters are brackishwater animals and consequently must have had some connection with the open sea. The most westerly collection 

of the ·Cannonball marine fauna is only 30 miles east of 

this place, in sec. 21, T. 129 N ., R. 100 W., 4 miles west 

of Haley, and occurs stratigraphically within 100 feet of 

the T Cross lignite bed, which was traced from T. 134 N ., 

R. 105 W., to the west side ofT. 129 N., R. 101 W. The 

oysters occur about 70 feet above the same lignite bed; it 

is assumed that the seaward connection was to the east. 

The oysters also occur about 120 feet below the base of 

the Fort Union formation, which in the Little Missouri 

region has the same characteristics (channel conglomerate, 

light-yellow, somewhat massive sandstone) as it does in 

the Cannonball River country, where it rests directly on 

the Cannonball marine member. It appears that the sea 

in which were deposited some 300 feet of marine sediments transgressed westward across the lignitic strata of 

the Ludlow member and that the position of its westward 

limit is underneath the divide between the drainage of 

Little Missouri and that of Grand and Cannonball rivers. 

All of the Triceratops collected in the Little Missouri 

country came from below the T Cross lignite bed and the 

oysters from above it. Calvert, however, states that in 

Montana "ceratopsian bones were found just above the 

lowest persistent lignite bed, but there is certainly nothing 

in the character of the overlying strata to suggest that 

1 Stanton, T. W,, The age and stratigraphic relation-;; of the " OeTatops 

beds" of Wyoming and Montana: Washington Acad. Sci. Proc., vol. 11, 

p. 249, 1909: Fox Hills sandstone and Lance formation('' Ct:ratops beds'') 

in South Dakota and eastern Wyoming: Am. Jour. Sci., 4th ser., vol. 30, 

pp. 1~184, 1910. 

TERTIARY SYSTEM. 

Lloyd and Hares discuss the Fort Union 

formation and overlying rocks as follows: 

FORT UNION FORMATION. 

West of Missouri River the Fort Union formation overlies the Cannonball member of the Lance, and on Little 

Missouri River it overlies the Ludlow lignitic member of 

the Lance. In this part of the Dakotas a large part of the 

formation has been removed by erosion, but in Billin:,c-s 

County, N. Da.L, one of the writers (Hares) has found a 

thickness of 1,025 feet. The formation consists of calcareous sandstone and shale of continental origin, containing 

numerous thick persistent beds of lignite and an abundant 

flora and fresh-water invertebrate fauna. Some of the 

thick lignite beds have burned extensively,- and great 

numbers of red hills composed of fused and baked rock 

are characteristic features of the formation. The lower 

100 feet of the formation is made up almost wholly of partially consolidated yellow and gray fine-grained sandstone, which is in some localities indistinguishable from 

the sandstone at the top of the Cannonball member. At 

numerous other exposures, h'owever, where the upper bed 

of the Cannonball member is a sandy shale, the contact is 

easily followed. At one locality on the north bank: of 

Heart River in T. 136 N., R. 88 W., there is an erosion 

channel from 30 to 50 feet deep in the Can:rionball member 

filled with the channel deposits of a Fort Union stream. 

Similar channel sandstones at the base of the Fort Union 

were seen along Little Missouri, near Yule, and at the 

mouth of Deep Creek, and also on Sand Creek, in Billings 

2 Calvert, W. R., and othE>rS, Lignite in ea..~tem Montana: U.S. Geol. 

Survey Bull. 471, p. 197, 1912. 

• 
• 

10 SHORTER CONTRIBUTIONS TO GENERAL GEOLOGY, 1920. 

County, N. Dak. These strata show evidence of-a rapid 

change in the character of the sedimentation. They consist predominantly of coarse sandstone containing lenses 

or pockets of conglomerate and of soft clay shale. The 

conglomerate consists of pebbles derived from the strata 

of the surrounding region and contain numerous waterworn bon~, teeth, fish scales, fragments of silicified wood, 

and lignite in the form of tree trunks. Among the vertebrate remains are two mammalian teeth wh,ich have been 

identified by Dr. J. W. Gidley, of the U. S. National 

Museum, as Euprotogonia sp., second lower molar of left 

jaw, and Pantolamda cavirictus, upper premolar. Both of 

these species are found in the Fort Union beds of Sweetgrass County, Mont. The remaining fragments are identified as representing Champsosaurus, a crocodile, a turtle, 

and Lepisosteus. 

Lenses of conglomerate similar to the one. ~ascribed above 

were seen at other localities near the base of the Fort 

Union along Heart River, a.nd in one exposure a bed of 

conglomerate a few inches thick forms the base of the 

formation. Along Little Missouri in sec. 31, T. 138 N., 

R. 102 W., a conglomerate at the base of the Fort Union 

contains boulders up to a foot in diameter. The unconformity shown in these exposures is such ae would be 

expected in a transition from marine to continental sedimentation. 

ROCKS OF POST-FORT UNION AGE. 

The rocks of post-Fort Union age in this region embrace 

(1) small re:ri:mants of sandstone, marl, and limestone of 

the White River formation on the tops of a few high buttes; 

(2) sand and gravel beds on the tops of high buttes, probably deposited by streams previous to the present cycle 

of erosion and deriv-ed in part from the White River formation; (3) terrace gravel in the valleys of the larger streams 

from 50 to 250 feet above the present valley floors; and 

(4) a large number of scattered glacial boulders, the remnants of the drift of one of the earlier glacial epochs. These 

later rocks occupy small areas ap.d are not shown on the 

accompanying map. 

FAUNAL RELATIONS. 

SPECIES COLLECTED. 

The following species have been collected in 

the Cannonball marine meml?er of the Lance 

formation: 

Nodosarla sp. 

Cristellaria sp. 

Trochocyathus dakotaensis Vaughan, n. sp. 

Trochocyathus? neumani Vaughan, n. sp. 

Paracyathus lloydi Vaughan, n. sp. 

Paracyathus thomi Vaughan, n. sp. 

Paracyathus kayserensis Vaughan, n. sp. 

Steriphonotrochus leithensis Vaughan, n. sp. 

Solemya bilix White. 

Nucula planimarginata Meek and Hayden. 

Nucula subplana Ueek and Hayden? 

Leda mansfieldi Stanton, n. sp. 

Yoldia scitula Meek and Hayden. 

Y oidia evansi Ueek and Hayden. 

Yoldia thomi Stanton, n. sp. 

Cucullaea shumardi Ueek and Hayden. 

Cucullaea nebrascensis Owen? 

Culcullaea solenensis Stanton, n. sp. 

Trigonarca? hancocki Stanton, n. sp. 

Glycimeris subimbrica~ (Meek and Hayden) .. ' 

Pedalion lloydi Stanton, n. sp. 

Pteria linguaeformis (Evans and Shumard). 

Modiolus schallerensis Stanton, n. sp. 

Crenella cedrensis Stanton, n. sp. 

Crenella elongata Stanton, n. sp. 

Pholadomya hares:i. Stanton, n. sp. 

Anatina subgracilis (Whitfield). 

Arctica ovata (Meek and Hayden). 

F..riphyla mandanensis Stanton, n. sp. 

Crassatellites evans:i. !leek and Hayden. 

Corbicula cytheriformis Meek and Hayden. 

Corbicula berthoudi White. 

Lucina cedrensis Stanton, n. sp. 

Callista (Dosiniops:iB) nebrasceruds Meek and Hay· 

den. 

Callista (Dosiniops:i.s?) deweyi Meek and Hayden. 

Corbula mactriformis Ueek and Hayden. 

Panope s:i.mulatrix Whiteaves? 

Teredo selliformis Ueek and Hayden. 

Teredo globosa Ueek and Hayden. 

Dentalium pauperculum Meek and Hayden. 

Turbonilla cordensis Stanton, n. sp. 

Epitonium dakotense Stanton, n. sp. 

Lunatia obliquata Hall and Meek. 

Lunatia subcrassa Ueek and Hayden. 

Turritella haresi Stanton, n. sp. 

Anchura (Drepanochilus) americana var. pusilla 

Stanton n. var. 

Anchura (Drepanochilus) perveta Stanton, n. sp. 

Anchura (Drepanochilus) perveta var. gracilis Stanton, n. var. 

Calyptraphorus septentrionalis Stanton, n. sp. 

Cantharus (Cantharulus) vaughan.i (Meek and Hayden). 

Pyrifusus (Neptunella) newberryi (Meek and Hayden). 

Pyrifusus (Neptunella) gracilis Stanton, n. sp. 

· Levifusus? tormentarius Stanton, n. sp. 

Pyropsis hancocki Stanton, n. sp. 

Fasciolaria lloydi Stanton, n. sp. 

Fasciolaria? mandanensis Stanton, n. sp. 

Fasciolaria? cordensis Stanton, n. sp. 

Fasciolaria .(Mesorhytis) dakotensis Stanton, n. sp. 

Psilocochlis? occidentalis Stanton, n. sp. 

Turris lloydi Stanton, n. sp. 

Turris cordensis Stanton, n. sp. 

Turris? tormentaria. Stanton, n. sp. 

Turricula janesburgensis Stanton, n. sp. 

Turricula textilis Stanton, n. sp. 

Turricula baca.ta Stanton, n. sp. 

Turricula cincta Stanton, n. sp. 

Turricula? contorta (Meek and Hayden). 

Ringicula dubia Stanton, .11. sp. 

Cylichna scitula Meek and Hayden? 

Cylichnella dakotensis Stanton; n. sp. 

Lamna cuspidata Agassiz. 

Otodus obliquus Agassiz. 
FAUNA OF CANNONBALL MARINE MEMBER OF LANCE FORMATION. 11 

In the above list the following five forms 

suggest brackish-water deposits because the 

identical or closely related species are known 

with only brackish-water or fresh-water associates in other formations: 

Modiolus schallerensis. 

Corbicula cytheriform.:.S. 

Corbicula berthoudi. 

Panope simulatrix. 

Corbula mactriformis. 

In the Cannonball collections, however, they 

are all associated at ·the same localities with 

marine species, and in only one small lot 

(from sec. 22, T. 132 N., R. 86 W., 1 mile west 

of Schaller, N. Dak.) is there a predominance 

of Modiolus, Oorbicula, and Oorbula so as to 

suggest a brackish-water deposit. There are 

no oysters except in the extralimital area on 

Little Missouri River, where the beds containing Ostrea glabra Meek and Hayden and 

Ostrea subtrigonalis Evans and Shumard are 

believed to be contemporaneous with the 

Cannonball member. With these exceptions 

the fauna is strictly marine. It includes 2 

species of Foraminifera, 6 of corals, 60 of 

mollusks, and 2 of sharks. The Foraminifera 

and the corals belong to genera that range from 

Mesozoic to Recent. The sharks (represented 

by teeth only) are identified with species that 

are recorded from Upper Cretaceous, Eocene, 

and Miocene. 

COMPABISON WITH CRETACEOUS FAUNAS. 

Of the 60 molluscan forms 33 (including one 

variety) are described as new and 27 are identi:fied with previously described forms, of which 

5 were originally attributed to the Fox Hills 

sandstone but came from localities now known 

to belong to the-Cannonball marine member of 

the Lance formation, as follows: 

Glycimeris ~ubimbricata. 

Arctlca ovata. 

Teredo selliformis. 

Teredo globosa. 

Cantharus ( Cantharulus) vaughani. 

Arctica ovata has since been recorded from 

the Bearpaw shale, and Oantharus. ( Oantharulus) vaughani from the Fox Hills sandstone. It 

will be profitable to group all the 25 species 

having an outside distribution according to the 

formations in which they are found. The 

largest list is in the Fox Hills fauna, as follows: 

Solemya bilix. 

N ucula planimarginata. 

Y oidia scitula. 

Y oidia evansi. 

Cucullaea shumardi. 

Cucullaea nebrascensis. 

Pteria linguaeformis. 

Callista (Dosiniopsis) nebrascensis. 

Callista (Dosiniopsis?) · deweyi. 

Panope simulatrix. 

Dentalium paupercubm. 

Lunatia obliquata. 

Lunatla subcrassa. 

Anchura (Drepanochllus) americana. Represented 

in Cannonball by \lar. pusilla. 

Cantharus (Cantharulus) vaughani. 

Pyrlfusus (N eptunella) newberryi. 

Turricula? contorta. 

Cylichna scitula. 

Several of the same species with a few others 

are found in the Pierre shale, as follows: 

N ucula sub plana. 

Yoldia scitUia. 

Y oidia evanai. 

Pteria linguaeformis. 

Anatina subgra.cilis. 

Crassatellites evansi. 

Callista (Dosiniopsis) nebrascensis. 

Callista (Dosiniopsis?) deweyi. 

Dentalium pauperculum. 

Lunatia obliquata. -

Anchura (Drepanochllus) americana. Represented 

in Cannonball by var. pt~silla. 

Pyrifusus (N eptunella) newberryi. 

In areas farther west where the Pierre shale 

is represented by several formations, in part 

marine, such as the Bearpaw, Lewis, and Claggett shales, and in part continental, such as the 

Judith River and Mesaverde formations, these 

equivalents also have several species in common with the Cannonball member. The following species occur in the Bearpa w shale: 

N ucula plani:m.argin.ata. 

Nucula subplana. 

Callista (Dosiniopsis?) deweyL 

Lunatia subcrassa. Type from Claggett shale. 

Anchura (Drepanochilus) americana. Represented 

in Cannonball by var. p·usilla. 

Arctica ovata. 

The following species oc{{ur m the Judith 

River formation: 

Corbicula cytheriformis. Found also in Mesaverde. 

Panope simulatrix? 

The brackish-water beds in the Laramie 

formation, which overlies the Fox Hills sandstone in northeastern Colorado, also have 
12 SHORTER CONTRIBUTIONS TO GENERAL GEOLOGY, 1920. 

yielded three species found in the Cannonball 

member: 

Corbicula cytheriform.is. 

Corbicula berthoudi. 

Panope simulatrix? 

The fauna contains one species, Oorbula 

mactrijormis, which is found in the basal part 

of the overlying Fort Union formation associated with fresh-water mollusks. This is the 

only species in the Cannonball fauna that is 

known to range into a later formation, presumably because it was the only.one that was 

able to adapt itself to a fresh-water habitat. 

All the others with an outside distribution are 

found in older formations of 'the Upper Cretaceous in the same general region. A considerable proportion of the species described 

as new are also more or less closely related 

to Cretaceous species. It is evident, therefore, 

that a large element in the Cannonball fauna 

is directly descended without specific change 

or with only slight change from the preceding 

Cretaceous faunas of the Rocky Mountain and 

Great Plains region. These late Cretaceous 

faunas show a progressive modernization due 

to the gradual elimination of distinctive 

Mesozoic generic types and the concurrent 

introduction of modern generic types which 

continued through the Tertiary and are still 

living in the Recent fauna. For example, the 

strictly Cretaceous Inoceramus, Baculites, and 

Placenticeras, which are so abundant in the 

Pierre shale, are not knoWn in the Fox Hills 

sandstone, and many of the much more diversified gastropods and other new elements in 

the Fox Hills fauna have so modern an aspect 

that Meek and Hayden said in one of their 

early papers: 1 

Many of the species approximate so closely to Tertiary 

forms that did we not find them everywhere associated 

with Ammonites, Scaphites, and other genera which are 

known not to have existed later than the Cretaceous 

epoch, we should at once pronounce the formation in 

which they occur Tertiary. 

The ammonite Sphenodiscus and the various 

forms of Scaphites which characterize the Fox 

Hills fauna. and prove it to be Cretaceous were 

not descendants of earlier species in the Interior province but were immigrants from some 

other area, probably the Gulf province, which 

arrived about the beginning of Fox Hills time. 

1 Acad. Nat. Sci. Philadelphia Proc., vol. 9, p. 113, 1857. 

They have not been found in the Cannonball 

marine member of the Lance formation, and 

the direct evidence of its Mesozoic age that 

their presence would afford is therefore lacking. The genus Anchura, which is a conspicuous element in the Cannonball fauna, may be 

claimed as a strictly Mesozoic type, though the 

related genus Aporrhais continued on to the 

present. The Cannonball forms of Anchura 

appear to be direct descendants from those in 

the Pierre and Fox Hills. 

To recapitulate, 40 per· cent of the molluscan species in the Cannonball fauna are 

known in the combined Pierre and Fox Hills, 

or Montana fauna of the same general region, 

and 30 per cent of them have been found in 

the Fox Hills fauna. In earlier statements I 

have spoken of the Cannonba11 fauna as a 

modified Fox Hills fauna, and the relationship 

is close enough to justify that term, but the 

fauna clearly belongs to the open sea and was 

modified after Fox IIills time by the extinction or emigration of the ammonoids and a 

few other Mesozoic types and by the introduction of a considerable number of new types 

that are not known in the Fox: Hills and 

Pierre faunas. The modification therefore can 

not be attributed to isolation and a long time 

interval under changed conditions, as has been 

suggested 2 by some who seek an easy explanation of the disagreement in age determinations 

based respectively on the fossil animals and 

the fossil plants of the Lance formation. 

COMPARISON WITH TEB.TIABY FAUNAS. 

The single species which ranges into the 

overlying Fort Union formation .(Oorbula mactriformis) has already been mentioned, but as 

the Cannonball member is marine and the Fort 

Union and all other known Eocene formations 

of the Great Plains and Rocky Mountain 

region do not contain marine deposits, it is 

necessary to make comparisons with marine 

Eocene faunas of other areas. . The Eocene 

faunas of the Pacific coast evidently belong to 

2 This suggestion has been published by M. R. •'campbell (Griid&. 

book of the western United States, Part A,.Northern Pacific Route: 

U. S. Geol. Survey ~ull. 611, p. 53, 1915) in the following form: "Although the question is not firiany settled, it seems probable 'that the 

Cannonball member of the Lance formation is Tertiary and that the 

Cretaceous fauna w:hich occurs in it is merely a surviving remnant of 

an old Cretaceous fauna which formerly lived in the open sea but which 

as this sea became more and more restricted and eventually inclosed 

by land preserved its old form even into Tertiary time." 
FAUNA OF CANNONBALL MARINE MEMBER OF LANCE FORMATION. 13 

a totally different province and offer no basis for 

specific comparison. In the Gulf Coastal Plain 

the marine Tertiary faunas are well developed, 

and those of the lower Eocene (Midway and 

Wilcox groups), which are the only ones that 

need be compared with the Cannonball fauna, 

have been monographed in a preliminary way 

by G. D. Harris.1 

These faunas apparently contain no forms 

that are specifically identical with any of those 

found in the Cannonball fauna, though there 

are a few somewhat closely related species and 

there is some general faunal resemblance caused 

by the fact that the faunas have a large proportion of genera in common. These common 

genera were almost all introduced in unquestioned Cretaceous deposits and are present in 

the Pierre and Fox Hill faunas. As an example the Turritidae may be cited. This family 

is represented in the Cannonball fauna by a 

number of forms described as Turris and Turricula. In both the Midway and Wilcox faunas 

the family has a still greater development, including several species, especially in the Wilcox, of the same general aspect as some of the 

Cannonball species. Thus Turris lloydi Stanton may be compared with Pleurotoma nebulosa 

Harris, and Turricula janesburgensis Stanton 

with Pleurotoma nasuta Whitfield, but the ancestors of these groups are found in the Fox 

Hills and Pierre faunas. In other molluscan 

groups Pholadomya haresi Stanton may be 

compared with P. mauryi Harris, Levifusus? 

tormentarius Stanton with L. trabeatus Conrad, 

and Oalyptraphorus septentrionalis Stanton with 

0. velatus Conrad. The genus Oalyptraphorus, 

which is represented in the Cannonball collections by a single fragmentary specimen, has 

heretofore been known in American rocks only 

in the Eocene ranging from Midway to Jackson, 

·but in India it is apparently presQnt in the Cretaceous (Trichinopoly and Arrialoor groups), 

because, in my opinion, Gabb was justified in 

referring Rostellaria palliata Forbes to Oalyptraphorus. The genus Oylichnella, represented 

by 0. dakotensis, has not been recorded in rocks 

older than Tertiary. Some of the other genera 

found in the Cannonball fauna, such as Leda, 

Yoldia, Nucula, Oucullaea, Glycimeris, Pedalion, Pteria, Modiolus, and Orenella, have been 

represented by similar types from the Cretaceous to the present time and do not mean 

much unless specific identity is involved, when 

they may become important in showing direct 

connection between faunas. 

The Cannonball fauna has the general aspect 

of a Tertiary fauna on account of the absenc~ 

of most of the exclusively Mesozoic types and 

the preponderance of long-lived modern types, 

but its close relationship with the Cretaceous 

is shown by the fact that 24 of its species ( 40 

per cent of its known molluscan fauna) are 

identified with species found in the late Cretaceous . formations of the same general region, 

and 18 of the species (30 per cent) are known in 

the Fox Hills fauna. This rather close faunal 

relationship is interpreted to mean that the 

time interval between the Fox Hills and the 

Cannonball was not very long. 

CONTRAST BETWEEN CRETACEOUS AND EOCENE 

FAUNAS OF ATLANTIC AND GULF COASTAL 

PLAIN. 

The ammonite genus S phenodiscus, the types 

of Scaphites, and some other fossils found in 

the Fox Hills sandstone indicate that the Fox 

Hills is the approximate equivalent of the 

upper part of the Exogyra costata zone, which 

lies near the top of the Cretaceous in the 

Atlantic and Gulf Coastal Plain. It will 

therefore aid in fixing the place of the Cannonball member in the general time scale to compare the faunal relations between it and the 

Fox Hills, as briefly presented above, with the 

relations existing between the Iatest Cretaceous 

and earliest Eocene faunas of the Coastal 

Plain. The latter subject is ably discussed by 

Stephenson, 2 from whose paper ~he following 

statement is quoted: 

At no place known between Maryland and the Rio 

Grande are the Upper Cretaceous deposits immediately 

below the Eocene contact markedly younger than the 

upper part of the Exogyra costata zone of the eastern 

Gulf region, nor are the Eocene deposits immediately 

above the contact older t~ the Midway. In this connection it should be stated that the Rancocas and Manasquan formations of New Jersey, which carry only a meager 

fauna, are thought to be somewhat younger than the 

Exogyra costata zone, and the upper part of the Escondido 

formation of southwestern Texas may be a little younger 

than that zone, although its fauna 1s composed of strictly 

Mesozoic types, of which the genus Sphenodiseus is the 

1 The Midway stage: Bull. Am. Paleontology, vol. 1, pp. 17-270, pis. 2 Stephenson, L. W., The Cretaceous-Eocene contact in the Atlantic 

11-25, 1S96; The lignitic stage: Idem, vol. 2, pp. 195-294, pis, 7-20, 1897; and Gulf Coa~tal Plain: U.S. Geol. Survey Prof. Paper 90, pp. 155-182, 

vol. 3, pp. 1-128, pis. 1-12, 1899. 1915. 

43595°-21-· 2 
14 SHORTER CONTRIBUTIONS TO GENERAL GEOLOGY, 1920. 

most striking example. The time represented by the 

unconformity at other places throughout the Coastal Plain 

is therefore approximately equal to or greater than the 

time represented by the unconformity in the eastern Gulf 

region. As the faunas above and below the contact are 

best known in the Gulf region the available data relating 

to that region form the chief basis for the statements which 

follow. 

During the time represented by the unconformity 

separating the Cretaceous and Eocene strata of the eastern 

Gulf region some very important changes took place in 

the molluscan life of the region. A preliminary study of 

the faunas has shown that 168 or more species belonging 

to the subkingdom Mollusca existed in the zone of Exogyra 

costata of the Upper Cretaceous. Of these not a single 

species is known with certainty to have been found in the 

basal Eocene or Midway formation. Several species 

of Cretaceous mollusks have been reported from basal 

Eocene beds at different places in the Atlantic and Gulf 

Coastal Plain, but when the records are critically examined 

more or less uncertainty is found in each record, either 

as to the correctness of the identifications or as to the 

authenticity of the localities at which they were reported 

to have been found. 

The 168 species of mollusks in the zone of Exogyra 

costata represent 89 genera. At least 20 of the more 

common of these genera became extinct before the Midway 

formation began to be "deposited, and these are enumerated 

in the list which follows. One whole order, the 

Ammonoidea, which included five or more genera, 

entirely disappeared. 

Genera common in the zone of Exogyra costata (Upper 

Cretaceous), which became extinct before the deposition 

of the Midway formation (Eocene). 

Breviarca. 

Nemodon. 

Gervilliopsis. 

Inoceramus. 

Exogyra. 

Paranomia. 

Liopistha. 

Cyprimeria. 

Legumen. 

lEnona. 

Linearia. 

Leptosolen. 

Penssolax. 

Pugnellus. 

Belemni tella. 

Order Ammonoidea: 

Baculites. 

Scaphites. 

Sphenodiscus. 

Hamites. 

Turrilites. 

The genus Trigonia, which is common in the zone of 

Exogyra costata, does not appear in the Eocene of the 

Atlantic and Gulf Coastal Plain but occurs rarely in the 

post-Cretaceous in other parts of the world. One genus, 

Hamulus, belonging to the subkingdom Vermes, or worms, 

became extinct. Some of the smaller forms of life, such 

as Foraminifera, Bryozoa, and Ostracoda, have not been 

studied critically, and it is not known what changes may 

have taken place among them. However, R. S. Bassler 

has found that a bryozoan fauna which occurs in the 

Rancocas, the youngest but one of the Upper Cretaceous 

formations of New Jersey, reappears in part with certain 

varietal changes in the A quia formation (Eocene) in 

Maryland. 

Although practically all the species of mollusks in the 

Midway formation are 'different from those found in the 

underlying Cretaceous, the number of genera that make 

their first appearance in the Midway is probably less than 

the number of Upper Cretaceous genera that became 

extinct in the interval represented by the unconformity. 

However, using Harris's paper, already cited, 1 as principal 

authority, the writer has been able to note at least seven 

common genera in the Midway that are not found stratigraphically below that level in the eastern Gulf region; 

these are Chama, V enericardia, Meretrix, Mazzalina, 

Calyptraphorus, Mesalia, and Enclimatoceras. Some of 

th€'se genera are known in the Upper Cretaceous in other 

parts of the world. 

Of the seven genera listed by Stephenson as 

common in the Midway fauna and not found at 

a lower level in that region only one, Oalyptraphorus, has been recognized in the Cannonball 

fauna (represented by a single broken specimen), and of the 20 genera common in the 

zone of Exogyra costata which became extinct 

before Midway time only Nenwdon, Linearia, 

Belemnitella, Scaphites, and Sphenodiscus are 

known in the Fox Hills fauna, and none of them· 

has been found in the Cannonball fauna. The 

considerable differences between the Fox Hills 

fauna and the fauna of the Exogyra costata zone 

are probably due in part to the differences in 

lithologic facies, in part to geographic separation, and possibly in part to differences in 

climate. Though both faunas belong to Atlantic 

waters as contrasted with the Pacific, there was 

certainly no direct broad connection in late 

Cretaceous time between the Mississippi ·embayment and the waters which covered the 

Great Plains area. 

The point to be emphasized in the preceding 

comparisons is that the connection between the 

Fox Hills and Cannonball faunas is closer than 

that between the faunas of the Exogyra costata zone and the Midway. Stephenson further 

discusses the magnitude of the faunal changes 

in passing from Cretaceous to Eocene in the 

Gulf region, compares the known floras, and 

finally concludes his interpretation of the 

hiatus in the following words: 

It is pretty generally conceded by paleontologists that 

evolutionary changes have proceeded more rapidly at cer- . 

tain times during the earth's history than at other times, 

but if this quickening of development is admitted the 

hiatus, in order to produce the observed changes, must 

have been of great duration even when measured in terms 

of geologic time. How much of that time should be 

classed with the Cretaceous and how much with the Tertiary can not be determined with the available data. It 

is reasonable to conclude, however, that Cretaceous time 

did not end with the deposition of the uppermost Cretaceous strata now preserved, nor did Tertiary time begin 

with the deposition of the lowermost Eocene strata. The 

line separating the two periods probably lies somewhere 

toward the middle of the hiatus. 

1 Harris, G. D., The Midway stage: Bull. Am. Paleontology, vol. 1, 

156 pp., 15 pl'3., 1898. 
FAUNA OF CANNONB.(LL MARINE MEMBER OF LANCE FORMATION. 15 

It is my opinion that the fauna of the Cannonball marine member of the Lance formation indicates that the formation belongs 

within the hiatus discussed by Stephenson and 

below the line which he postulates as separating Cretaceous from Eocene. It is certainly 

somewhat younger than the zone of Exogyra 

cpstata and most probably considerably older 

than the Midway formation. 

PALEOGEOGRAPIDC RELATIONS. 

Another line of evidence concerning the age 

of the Cannonball member is dependent on the 

geographic location of the Cannonball marine 

deposits and the geologic history of the region 

in which they are found. To state the facts 

bluntly, the Cannonball deposits are in the 

midst of a great area of marine Cretaceous 

rocks and a thousand miles from the nearest 

known marine Eocene rocks. The same facts 

are graphically presented in figures 2 and 3, 

which are adapted from Schuchert's paleogeographic maps 1 with the approximate area of 

the Cannonball member added. The characteristic feature of North American geography 

in Upper Cretaceous time was the great epi-

. continental sea which extended from the westem part of the Gulf of Mexico across the larger 

part of the Great Plains and Rocky Mountain 

regions far into Canada and probably connected with the Arctic Ocean. It began with 

the deposition of the Dakota sandstone and 

continued with some variations in area throughout the Colorado and Montana epochs. Figure 

2 shows its approximate form within the United 

States at the time the Pierre shale or lower part 

of the Montana group was laid down. It was 

then not quite so extensive as it had been in 

erfJd by the epicontinental sea of Pierre and 

Fox Hills time. 

Other marine areas of Upper Cretaceous time 

covered the Atlantic and Gulf Coastal Plain, 

with the Mississippi embayment extending up 

to the mouth of the Ohio, and the narrow 

Pacific Border region broadening into an embayment in Oregon. 

The Eocene map (fig. 3) shows relatively 

little change from the Cretaceous in the coastal 

border regions. The form of the Mississippi 

embayment remains about the same. The 

other submerged areas of the Atlantic and 

Gulf Coastal Plain and on the Pacific Border 

show only minor changes. But the great epicontinental sea ·of the western interior, which 

is so conspicuous on all Upper Cretaceous maps, 

has disappeared. There is no marine Eocene 

(unless the Cannonball member is Eocene) nor 

marine Tertiary of any kind between the 

Coastal Plain and the Pacific Border province; 

neither is any marine Eocene known between 

the Mississippi embayment and the Arctic 

coast. 

The comparatively small area in which the 

Cannonball member has been found lies about 

a thousand miles from the nearest Coastal 

Plain Eocene at the head of the Mississippi 

embayment and about the same distance from 

the nearest Pacific Border Eocene in Oregon 

and Washington. No other point in the 

United States is farther from known marine 

Eocene. Geographically and historically, therefore, the Cannonball marine member of the 

Lance formation is connected with the Cretaceous rather than the Eocene. 

SUMMARY. 

the Colorado epoch and there were varying The Cannonball marine member of the Lance 

areas within it of swamp, estuary, and flood formation lies immediately beneath the Fort 

plain with possibly some higher lands during Union formation and rests on continental 

both Colorado and Montana time. Its area deposits of the Lance formation, which in turn 

in Fox Hills time, though not quite so definitely overlie the marine Cretaceous Fox Hills sanddetermined, was probably somewha-t smaller stone. 

than in Pierre time, but Fox Hills deposits are Its fauna is strictly marine and includes 2 

known from southern North Dakota through species of Foraminifera, 6 of corals, 60 of 

eastern Montana and eastern Wyoming to mid- Mollusca~ and 2 of sharks. While its molluscan 

die Colorado east of the Front Range. The fauna has a modern aspect, on account of the 

Cannonball marine member of the Lance forma- lack of ammonoids and other distinctively 

tion is well within the area that had been cov- Mesozoic groups, it is conn'3cted with the 

1 SchuchHt, Charles, Paleogeography of North America: Geol. Soc~ preceding late Cretaceous faunas of the same 

America Bull., vol. 20, pls. :!5, 913, 1908. region by the specific identity of 40 per cent 
Cannonball 

-

marine member 

of Lance formation 

0 100 300Scale 500 700Mile.s 

Pacific marine 

Upper Cretaceous 

Interior ~ marine 

Upper Cretaceous 

Atlantic .~ and Gulf marine 

Upper Cretaceous 

FIGURE 2.-Ske,ch map showing position of marine J,ance dr-posits with reference to Upper Cretaceou:'l Pierre sea. 

1-' 

~ 

w. 

~ 

~ ~ 

a 

0 

~ 

~ ~ 1-1 

0 

z 

r:n 

1-3 

0 

c;':) 

t;lj 

~ t;lj 

~ 

~ 

~ 0 

~ ....... 

~ 

!! 
, 100 JOOScale 500 700 Miles 

-

Cannonball marine member Pacific ~ marine Eocene Atlantic and .~ Gulf marine Eocene 

of Lance formation 

FIGURE 3.-Sketch map showing position of marine Lance deposits with referen,ca to Eocene seas. 

"'::! 

> q 

!2l 

> 

0 

"'::! 

n 

~ !2l 

0 

~ 

~ 

~ ~ 

tr.l 

~ tr.l 

t:= 

td 

tr.l 

t:d 

0 

l'%_j 

t""' 

~ a 

tr.l 

"'::1 

0 

t:d 

~ 

~ 0 

~ 

~ 

-:r 
18 SHORTER CONTRIBUTIONS TO GENERAL GEOLOGY, 1900. 

of its species. No Eocene species have been 

identified in it except one from the Fort Union. 

Geographically and historically the Cannonball member is much more closely connected 

with the Cretaceous than with the Eocene, for 

the reason that it is in the midst of an area 

that was covered by the sea practically throughQUt Upper Cretaceous time, while it is a 

thousand miles distant from recognized marine 

Eocene deposits. 

The conclusion is therefore reached that the 

Cannonball marine member and consequently 

the whole of the Lance formation is of Cretaceous age. 

In subsequent pages the species will be 

described and illustrated, so that others may 

see the paleontologic evidence and form an 

independent judgment of the validity of the 

·conclusions based upon it. 

No attempt is here made to harmonize or 

explain away the evidence of the flora found 

in the nonmarine portions of the Lance fornlation, which has led to a different age determination. Knowlton 1 says: 

The Lance flora embraces about 100 named and described species, as well as a considerable number not yet 

described. Of these 100 species, over 75 are typical Fort 

Union species that have never been found in older beds 

and most of them only in the Fort Union. 

As the Fort Union formation is generally 

accepted as Eocene this close relationship of 

floras was naturally held to be proof that the 

Lance formation is Eocene also. It is noteworthy that the Fort Union flora of about 500 

species, collected mainly in the Dakotas, 

Montana, and Wyoming, shows comparatively slight specific relationship with the more 

southern floras that have been referred to the 

Eocene. Thus the post-Laramie floras of the 

Denver Basin (Arapahoe with about 30 species 

and Denver with nearly 200 species) have 

about 30 species in common with the Fort 

Union according to Knowlton.2 The same 

author 3 states that the Raton flora of 148 

species contains only 10 Fort Union species, 

and Berry 4 reports only 12 Fort Union species 

1 Knowlton, F. H., Cretaceous-Eoc-ene houndary in the Rocky Mountain region: Geol. Soc. America Bull., vol. 25, p. 334, 1914. 

2 Knowlton, F. H., Succession and range of Mesozoic and Tertiary 

floras: Jour. Geology, vol. 18, p. 114, 1910. 

a Knowlton, F. H., Fossil floras of the Vermejo and Raton formations 

()f Colorado and New Mexico: U. S. Geol. Survey Prof. Paper 101, p. 

239, 1917. • Berry, E. W., Lower Eocene floras of southeastern North AmPxica: 

U. S. Geol. Survey Prof. Paper 91, p. 149, 1916. 

in the Wilcox flora of over 300 species. These 

statistics indicate that the number of Fort 

Union species found in other American lower 

Eocene floras is little if any larger than the 

number common to the western Cretaceous 

and Eocene floras 5 as determined by paleobotanists and suggest that the differences between the floras on either side of the "postLaramie unconformity" are not necessarily 

due to a long lapse of time. In my opinion 

the combined evidence from all sources is 

opposed to the existence of a very long unrepresented interval anywhere between Fox Hills 

and Wasatch deposition. 

Whatever may be the final verdict concerning the exact boundary between Cretaceous 

and Eocene in the interior of the United States, 

the Cannonball marine member of the Lance 

formation and its fauna record an important 

episode in the history of the region, and their 

evidence must be given full weight before a 

correct decision can be made. 

DESCRIPTION OF SPECIES. 

Phylum PROTOZOA. 

Class RHIZOPODA. 

Order FORAMINIFERA. 

Family LAGENIDAE. 

Genus NODOSARIA Lamarck. 

Nodosaria sp. 

Plate I, figure 13. 

A small, slender, slightly curved, strongly 

costate species of Nodosaria resembling N. 

zippe·i Reuss is represented by five specimens 

preserved as natural molds in sandy clay shale 

collected in the Cannonball marine member of 

the Lance formation at locality 8388, in a railway cut 4 miles southwest of Lark, N. Dak., 

in the SW. i sec. 15, T. 134 N., R. 86 W. 

The figure is made from a gutta-percha 

squeeze or" a small fragment which retains the 

surface sculpture fairly well. It measures 2.5 

millimeters in length and consists of seven 

chambers. The largest specimen collected is 

10 millimeters long and has about 20 chambers. 

Genus CRISTELLARIA Lamarck. 

Cristellaria sp. 

A single specimen of OristeUaria about a 

millimeter in diameter was collected in the 

5Knowlton gives the number as 21 or 22: Geol. Soc. America Bull., 

vol 25, p. 332, 1914. 
FAUNA OF CANNONBALL MARINE MEMBER OF LANCE FORMATION. 19 

Cannonball marine member of the Lance formation at locality 8463, in theSE. ! sec. 19, T. 136 

N., R. 87 W., on· Heart River 7 miles southwest 

of AliDDnt, N. Dak. Unfortunately the specimen was lost while under study, but it 

resembled 0. mamilligera Karrer as figured in 

Geological Survey of New Jersey, Paleontology, 

volume 4, plate 3, figure 8. 

Phylum COELENTERATA. 

Six species of corals belonging to the family 

Caryophylliidae are described by T. W. Vaughan 

in the accompanying paper (pp. 61-66). 

Phylum MOLLUSCA. 

Class PELECYPODA. 

Family SOLEMYACIDAE. 

Genus SOLEMYA Lamarck. 

Solemya bilix White. 

Plate I, figures la and lb. 

Solemya bilix White, U. S. Nat. Mus. Proc., vol. 3, p. 158, 

1881; vol. 4, pp. 137, 139, pl. [not numbered], fig. 9, 

1882. 

Original description: 

Shell about two and a half times as long as high, broader 

anteriorly than posteriorly; both ends rounded, the 

They differ from the type only in their smaller 

size (length 9 to 15 millimeters) and better 

state of preservation, and they seem to have 

been correctly identified. 

The five specimens collected at three different 

localities in the Cannonball member range in 

length from 15 to 24 millimeters. They agree 

perfectly in form with 8. bilix and are confidently referred to that species, though none 

of them shows the surface sculpture well 

enough to determine whether or ·not the 

radiating l~es have a paired arrangement on 

the middle part of the shell. The internal 

casts among the Colorado specimens, as well as 

those from North Dakota, fail to show this 

feature, although they bear numerous very 

fine radiating lines. 

Locality and position: The figured specimen 

was collected near the top of the hill in the 

northern edge of Mandan, a short distance 

west of the courthouse. Other specimens were 

obtained on Heart River 11 miles north of 

Flasher and on the west bank of Missouri River 

1 mile south of Price and 19 miles north of 

Mandan, N. Dak., all in the upper part of the 

Cannonball marine member of the Lance 

formation. 

posterior one more narrowly so than the other; both dorsal Family NUCULIDAE. 

and basal margins gently convex or nearly straight; test Genus NUCULA Lamarck. 

thin and fragile; valves moderately convex from above 

downward, the greatest convexity in that direction being Nucula planimarginata Meek and Hayden. 

near the dorsum; beaks having the usual inconspicuous Plate I, figures 2 and 3. 

character comrnon to the genus, situated near posterior 

end; ligament necessarily short but apparently well Nucula planomarginata Meek and Hayden, A cad. Nat. 

developed and resting upon a fulcrum of support of the Sci. Philadelphia Proc., vol. 8, p. 85, 1856 

usual character in each valve. Surface bright and, Nucula planimarginata (Meek and Hayden) Meek, U.S. 

besides the· usual lines of growth, marked by numerous Geol. Survey Terr. Rept., vol. 9, p. 101, pl. 15, 

faint radiating lines, which are visible to the unassisted figs. 8 a, b, an~ pl. 28, fig. 16, 1876. 

eye but are satisfactorily seen only under a lens, nearly Meek's description: 

uniformly distributed over the whole surface, but upon 

the middle portion they are arranged in pairs. Shell transversely subovate or subelliptic, compressed; 

Length, 20 millimeters; height at the broader part, posterior or shorter side obliquely truncated above and 

which is in front of the middle, 8 millimeters. abruptly rounded or subangular below the middle; ante- . rior or longer side cuneate and rather narrowly rounded; 

This description is based on a single specimen base forming a regular semielliptic curve, not crenate 

from a locality about 4 miles north of Golden, within; dorsum declining gently with a gradual convex 

Colo., where it was found in strata belonging to curve from near the beaks to the anterior extremity; beaks 

the Fox Hills sandstone or the upper part of small, incurved, nearly contiguous, and located about 

halfway between the middle and the posterior side; sur- the Pierre shale. In the second publication face marked by very fine, irregular, radiating, and minute 

cited White records the species as occurring at concentric striae; hinge forming at the beaks an angle of 

about the same horizon near Julesburg, Colo., about 110°, having in the adult some 26 or 27 denticles on 

but the collection referred to, consisting of the longer or anterior side of the beaks and aboutlObehind · 

about 50 well-preserved specimfm.s, all con- in each valve; lunule-like area behind the beaks lanceovate, flattened along each side, and a little convex in the siderably smaller than the type, is in the middle. 

National Museum labeled "Narrows of South Length, 0.95 inch [24 millimeters]; height, 0.66 inch 

Platte River, 50 miles east of Greeley, Colo." [16.75 millimeters]; convexity, 0.38 inch [9.6 millimeters] 
20 SHORTER CONTRIBUTIONS TO GENERAL GEOLOGY, 1920. 

Locality and position: The types came from 

the Fox Hills sandstone on Moreau River, 

S. Dak., and near Long Lake, N. Dak. The 

species has also been collected in the Fox Hills 

sandstone in northern Colorado west of Greeley, 

in about the same stratigraphic position on 

Deer Creek near North Platte River, Wyo., 

and in the Bearpaw shale on Fish Creek and 

5 miles north of Musselshell post office, Mont. 

The specimens here figured were collected in 

the Cannonball marine member of the Lance 

formation in the SW. ± sec. 34, T. 23 N., R. 17 

E., 9 miles east of Lemmon, S.Dak., and on the 

west bank of Missouri River 1 mile south of 

Price and 19 miles north of Mandan, N. Dak. 

Other specimens were obtained 3 and 6 miles 

east of Flasher, N. Dak.; 5 miles southeast of 

Strain, in sec. 21, T. 136 N., R. 82 W., N.Dak.; 

and in sec. 24, T. 23 N., R. 9 E., one-fourth 

mile east of Bloom, S. Dak. 

Nucula subplana Meek and Hayden? 

Plate I, figures 4-7. 

Nucula sub plana Meek and Hayden, A cad. Nat. Sci. 

Philadelphia Proc., vol. 8, p. 85, 1856. 

Meek, U. S. Geol. Survey Terr. Rept., vol. 9, p. 99, 

pl. 17, figs. 7 a, b, 1876. 

Meek's description: 

Shell small, broad ovate, approaching subtrigonal, much 

compressed, with height about four-fifths the length; 

posterior or shorter side obliquely truncated above and 

narrowly rounded below; anterior side longer and more 

broadly rounded; basal margin semiovate in outline, not 

crenulate within; dorsum declining a little with a slightly 

convex curve from the beaks anteriorly, and a little concave and sloping abruptly behind; beaks moderately 

prominent, compressed, and located about halfway between the middle and the posterior or shorter side; teeth 

of the hinge about 15 in each valve in front of the beaks 

and a smaller number behind; muscular and pallial impressions faintly marked. (Surface unknown.) 

I~ength, 0.37 inch [9.4 millimeters]; height, 0.26 inch 

[6.6 millimeters]; breadth, 0.12 inch [3 millimeters]. 

In the collection from the Cannonball member there are numerous specimens of Nucula 

which are of about the same size as N. planimarginata and in the preliminary lists were 

referred to that species. Closer study and 

comparison have shown that they differ from 

N. planimarginata in several particulars, being 

relatively higher, more compressed, and with 

the posterior end more obliquely truncate, but 

the two species agree in having the ventral 

border smooth within and the surface marked 

only by very fine radiating and concentric 

lines. In form and outline these specimens 

agree so closely with the types of N. subplana 

that they are doubtfully referred to that 

species on the assumption that Meek and 

Hayden's types are immature specimens. 

One of the shells figured, which is of about 

average size, measures 20 millimeters in length, 

16 millimet~rs in height, and about 8 millimeters in convexity. 

Locality and position: The types of the species came from the upper part of the Pierre 

shale on "Yellowstone River, 150 miles from its 

mouth," near Glendive, Mont. The larger shells 

here figured are especially abundant in the 

upper part of the Cannonball marine member 

of the Lance formation on the west bank of 

Missouri River 1 mile south of Price and 19 

miles north of Mandan, N. Dak. The form has 

also been collected in the Cannonball member 

7 miles south of Leith, N.Dak.; 7 miles southwest and 8 miles southeast of Lemmon, S. Dak. 

(fig. 7); 3 and 6 miles east of Flasher, N. Dak; 

and 3! miles west of Haley, N. Dak.; also in 

the Bearpaw shale on Fish Creek and 5 miles 

north of Musselshell, Mont. 

Family LEDIDAE. 

Genus LEDA Schumacher. 

Leda mansfieldi Stanton, n. sp. 

Plate I, figure 8. 

Shell small, transversely sublanceolate, compressed; anterior end broadly rounded; pos- · 

terior end narrowly subangular; anterior third 

of basal margin broadly rounded, rest of base 

nearly straight but bending up in a slight curve 

to the posterior end; dorsal margin nearly 

straight and horizontal in front of the beak, 

descending in a concave curve behind; beaks 

not conspicuous, very slightly in advance of 

the middle. Surface marked by very fin·e concentric lines which are about equal to the 

inters paces. 

Length of type, 10 millimeters; height, 5 

millimeters; convexity of both valves, about 

2 millimeters. Another specimen with about 

the same proportions is 13 millimeters long. 

The species is named for Mr. W. C. Mansfield, 

of the United States Geological Survey, who 

collected the type specimen. 

Locality and position: Cut on Northern Pacific Railway in the SW. ± sec. 15, T. 134 N., 

R. 86 W., about 4 miles southwest of Lark, 
FAUNA OF CANNONBALL MARINE MEMBER OF LANCE FORMATION. 21. 

N.Dak., in bluish shale very near the top of the 

Cannonball marine member of the Lance formation. It was also found in the lower part 

of the member in T. 134 N., R. 81 W., about 6 

miles northwest of Solen, N. Dak., and 7 5 feet 

below the top of the member in the SE. f 

sec. 10, T. 138 N., R. 83 W., on Heart River 

abo~t 15 miles southwest of Mandan, N. Dak. 

Genus YOLDIA Moller. 

Yoldia scitula Meek and Hayden. 

Plate I, figures 9 and 10. 

Nut:Ula scitula Meek and Hayden,· Acad. Nat. Sci. Philadelphia Proc., vol. 8, p. 84, 1856. 

Leda scitula Meek and Hayden, idem, vol12, p. 185, 1860. 

Leda (Yoldia) scitula Meek and Hayden, idem, vol. 12, p. 

428, 1860. 

Yoldia scitula Meek, U. S. Geol. Survey Terr. Rept., vol. 

9, p. 110, pl. 28, fig. 9, 1876. 

Meek's description: 

Shell transversely subovate, gibbous in the central and 

umbonal regions; anterior extremity rather narrowly 

rounded; posterior side narrower and more co:Qlpressed, 

subangular or very narrowly rounded in outline, the most 

prominent part being above the middle; base forming a 

semiovate curve, sometimes very slightly sinuous near the 

middle; dorsum declining from the beaks; cardinal border 

of each valve having a distinct marginal groove behind 

the beaks, which forms, when the valves are united, a 

lanceolate, escutcheon-like depression; beaks rather obtuse, not oblique, placed a little in advance of the middle; 

surface marked by regular, fine, distinct, concentric lines, 

which are nearly equal to the grooves between, and more 

strongly defined on the middle than toward the extremities 

of the valves. 

Length, 0.40 inch [10 millimeters]; height, 0.21 inch 

[5.5 millimeters]; convexity, 0.20 inch [5 millimetersl 

Meek adds that the pallial sinus seen on 

internal casts is rather distinct though not 

deeper than is sometimes seen in the genus Leda 

and that the species is referred to Y oldia because the form of the shell agrees more nearly 

with that group. 

A few specimens in the Cannonball fauna 

agree so closely in size and form with this 

species that I do not hesitate to refer them 

to it, although the surface sculpture is not perfectly preserved. 

Locality and position: The types cam,e from 

Moreau River, S. Dak., and Long Lake, N. 

Dak., where they were found in the Fox Hills 

sandstone. The species is common in that for.;. 

mation and in the upper part of the Pierre shale. 

In the Cannonball marine member of the 

Lance formation it has been collected in sec. 

7, T. 22 N., R. 17 E., 8 miles southeast of 

Lemmon, S. Dak. (fig. 10), and in the SE. i 

sec. 10, T. 138 N., R. 83 W., on Heart River 

about 15 miles southwest of Mandan, N. Dak., 

where it occurs in a brown sandstone 75 feet 

below the top of the formation. 

Yoldia evansi Meek and Hayden. 

Plate I, figure 11. 

Nucula evansi Meek and Hayden, Acad. Nat. Sci. Philadelphia Proc., vol. 8, p. 84, 1856. 

Leda evansi Meek and Hayden, idem, vol. 12, p. 185, 1860. 

Leda (. Yoldia) evansi Meek and Hayden, idem, vol. 12, 

p. 429, 1860. 

Yoldia evansi Meek, U. S. Geol. Survey Terr. Rept., 

vol. 9, p. 117, pl. 28, figs. 10 a-c, 1876. 

Meek's description: 

Shell transversely elongate-subelliptical, depressed, 

rather compressed, or a little gibbous in the central and 

umbonal regions; both extremities narrowly rounded, the 

most prominent part of each being above the middle; 

basal margin nearly straight, parallel to the cardinal border 

along the middle, and rounding up gradually in front and 

behind; dorsal margin nearly straight, provided, behind 

the beaks, with a shallow groove in each valve; beaks 

depressed, small, and almost in contact, located a little 

in ad vance of the middle of the shell; surface smooth, 

excepting very obscure traces of fine concentric striae. 

Length of largest specimen, 0.77 inch [19.5 millimeters]; 

height, 0.36 inch [9 millimeters]; convexity, 0.26 inch 

[6.6 millimeters]. 

Locality and position: Types from Moreau 

River, S. Dak., in Fox Hills sandstone. The 

species is also common in·the upper part of the 

Pierre shale, in the Bearpaw shale, and other 

equivalents of the upper part of the Pierre. 

Two small specimens, one of which is figured, 

were found in the upper part of the Cannonball 

marine member of the Lance formation in a 

bluff on the north side of Heart River 1 mile 

west of Mandan, N.Dak. 

Yoldia thomi Stanton, n. sp. 

Plate I, figures 12a-12c. 

Shell small, transversely elongate subovate, 

moderately convex, especially in the umbonal 

region, · slightly gaping behind; .anterior end 

narrowly rounded; posterior end more narrowly 

rounded or subangular; base forming a regular 

gentle curve; dorsal margin descending from 

the beaks with a slightly convex curve in 

front and a slightly concave curve behind; 

lanceolate escutcheon bounded by a narrow 

obscure ridge in each valve; beaks prominent, 

obtuse, median in position; sUrface almost 
22 SHORTER CONTRIBUTIONS TO GENERAL GEOLOGY, 1920. 

smooth, marked only by extremely fine, somewhat irregularly spaced, concentric grooves 

which are much narrower than the intervening 

spaces. 

Length, 13 millimeters; height, 8 millimeters; 

convexity of both valves, 6 millimeters. 

·This species in a general way resembles 

Y. scitula Meek and Hayden, with which it 

was at first confused, but it is somewhat larger, 

relatively slightly higher, and less convex, and 

the surface sculpture is less conspicuous and 

differs in other details. There are also differences in outline due to more conspicuous 

beaks and a more symmetrical posterior end. 

The specific name is g~ven in honor of Mr. 

W. T. Thorn, jr., of the United States Geological 

Survey. 

Locality and position: On Cannonball River 

in sec. 28, T. 133 N., R. 88 W., about 7 miles 

southeast of Kayser, N.Dak., in the upper part 

of the Cannonball marine member.of the Lance 

formation. 

Family PABALLELODONTIDAE. 

Genus CUCULLAEA Lamarck. 

Cucullaea shumardi Meek and Hayden. 

Plate II, figures la and lb. 

Area (Cucullaea) shumardi Meek and Hayden, Acad. Nat. 

Sci. Philadelphia Proc., vol. 8, p. 86, 1856. 

Cucullaea shumardi Meek and Hayden, idem, vol. 8, p. 

285, 1856. 

Cucullaea fibrosa Sowerby, Meek and Hayden, idem, vol. 

12, p. 428, 1860. 

Cucullaea (Idonearca) shumardi Meek, U. S. Geol. Survey 

Terr. Rept., vol. 9, p. 86, pl. 28, figs. 15 a-g; pl. 29, 

fig. 4, 1876. 

This species, which is abundant in the Fox 

Hills sandstone at a numher of localities in the 

type area of that formation, is represented in 

the Cannonball fauna by the cast of a right 

valve, which is figured. At the posterior end 

it retains. a small portion of the shell including 

part of the hinge and ligamenta! area. In all 

the preserved features this specimen agrees 

with the types of the species, which are well 

illustrated in Meek's report above cited. 

Locality and position: In the NW. l sec. 9, 

T. 130 N., R. 90 W., about 10 miles southwest 

of Pretty Rock, N. Dak., in the upper part of 

the Cannonball marine member of the Lance 

formation. 

Cucullaea nebrascensis Owen? 

Cucullaea nebrascensis Owen, Report of a geological survey 

of Wisconsin, Iowa, and Minnesota, p. 582, pl. 8, 

figs. 1, la, 1852. 

Cucullaea (Idonearca) nebrascensis Meek, U. S. Geol. 

Survey Terr. Rept., vol. 9, p. 88, pl. 29, figs. 5 a, b, 

1876. 

Two small, ·fragmentary specimens, which in 

preliminary lists were referred to 0. shurnardi, 

more probably represent young individuals of 

0. nebrascens·is, with which they agree in general form and in details of the hinge. The 

published descriptions of the species are based 

on the large mature shells that do not show 

radiating sculpture, though 1feek states that 

"young individuals are probably provided 

with radiating costae.'' The two specimens 

here recorded are thin shelled, thus indicating 

immaturity, and are covered in the umbonal 

region with numerous small, flat radiating ribs 

which are just visible to the unaided eye. 

Locality and position: In the NW. ! sec. 9, 

T. 130 N., R. 90 W., about 10 miles southwest 

of Pretty Rock, N. Dak., in the upper part of 

the Cannonball marine member of the Lance 

formation. 

Cucullaea solenensis Stanton, n. sp. 

Plate II, figures, 2a, 2b, and 3. 

Shell of moderate size, transversely subovate 

in outline, convex, with prominent incurved 

beaks; anterior margin forming nearly a right 

angle with the long hinge line, regularly 

rounded below; basal margin broadly rounded, 

strongly crenulate within; posterior margin 

obliquely subtruncate; ligament area large, 

marked by very fine longitudinal lines, crossed 

by three strong, oblique, divaricating grooves. 

Surface marked by concentric lines of growth 

and by somewhat stronger but obscure radiating ribs. 

Length of best-preserved specimen, 35 millimeters; height from base to top of beak, 30 

millimeters; convexity of both valves, about 

35 millimeters. 

This species, which is represented in the collections by only three specimens, resembles 

C. .Yhuma.rdi in size and general appearance, 

but it is easily distinguished from that and all 

other described species from the upper ~Missouri 

country by the fact that its ventral margin is 
FAUNA OF CANNONBALL MARINE MEMBER OF LANCE FORMATION. 23 

•distinctly crenulated within. The crenulations are conspicuous on the casts of all three 

of the specimens and are also seen on the 

exfoliated edge of the shell in the specimen 

represented by figure 3. 

Locality and position: Near the top of the 

high mesa 6 to 7 miles northwest of Solen, 

N. Dak., in T. 134 N., R. 81 W., about 100 

feet. above the base of the .Cannonball marine 

member of the Lance formation. 

Family ARCIDAE. 

Genus TRIGONARCA Conrad. 

Trigonarea? haneoeki Stanton, n. sp. , 

Plate II, figures 4 and 5. 

Genus GLYCDriERIS Da Costa. 

Glyeimeris subimbrieata (Meek and Hayden). 

Plate II, figures 6a, 6b, and 7. 

Pectunculus subimbricatus Meek and Hayden, A cad. Nat. 

Sc., Philadelphia Proc., vol. 9, p. 146, 1857. 

Axinaea subimbricata Meek and Hayden, idem, vol. 12, 

p. 185, 1860. 

Meek, U. S. Geol. Survey Terr. Rept., vol. 9, p. 95, 

pl. 28, figs. 14 a-d, 1876. 

}..feek' s description: 

Shell subcircular or slightly longer than high, ,moderately convex, extremities rounded, the posterior side 

sometimes being a little broader and less regularly rounded 

than the· other; base forming a very nearly semicircular 

curve, and strongly crenulate within; hinge area rather 

small, marked by about five to seven distinct grooves; 

beaks almost central, rather gibbous, obtuse, and neither 

oblique nor distinctly incurved; hinge a little arched; 

Shell very small, subquadrate, very convex, teeth distinct, lateral ones oblique and curved, the con-

'\\tith height and length about equal; dorsal cave sides being turned outward from the middle; musmargin straight, nearly as long as the shell; cular impressions rather large but shallow. Surface ornaventral and anterior margins forming a nearly mented by distinct lines of growth, crossed by numerous regular, simple, depressed, radiating costae, about twice 

regular curve; posterior margin sub truncate as broad as the grooves between. 

and forming an angle of about 100° with the Length, 1.55 inches [39 millimeters]; height, 1.36 

dorsal margin; beaks prominent, submedian, inches [3Q millimeters]; convexity of the two valves, 1.03 

with a small furrow, more distinctly marked inches [26 millimeters]. 

on the cast than on the shell, descending from· This description is apparently based on a 

the point of t~e beak toward .the middle of the single valve (U.S.N. M. catalogue No. 309), 

ventral margin. Surface marked by fine both sides of which are figured, though from 

growth lines and by about 25 relatively strong the description of the plate it would be natural 

radiating ribs which are not quite as broad as to infer that Meek's figures 14a and 14d repthe interspaces. Hinge and other internal resent different specimens. A much smaller 

features unknown. specimen is also figured and described as a 

Length, 4 millimeters; convexity of single young individual of the species, though slight 

valve, about 2 millimeters. differences are pointed out which suggest the 

This species is represented by only two mi- possibility that it ·may belong to another 

nute valves, which may be immature individu- species. That there is some variation in form 

als of a larger species, though they can not be and proportions is shown by the specimens now 

the young of any of the species of OucuUaea or figured from recent collections. One of these 

Glycirneris here described. As the character (figs. 6a, 6b) is almost an exact duplicate of the 

of the hinge and of the muscular impressions is type and measures 39 millimeters in length, 36 

Un.known, the generic reference is questionable. millimeters in height, and 28 millimeters in 

· The name is given in honor of Mr. E. T. convexity. .Another specimen (fig. 7) is higher 

Hancock, of the United States Geological and more convex in proportion to its lengtn, 

Survey, who collected the types. measuring 40 millimeters in length, 42 milli-. 

Locality and position: In the SE. l sec. 10, meters in height, and 30 millimeters in conT. 138 N., R. 83 W., on Heart River about 15 vexity of both valves. In other respects all 

miles southwest of Mandan, N. Dak., 75 feet these specimens resemble one another so 

below the top of the Cannonball marine mem- closely that I have no hesitation in treating· 

her of the Lance formation. them as one species. 
24 SHORTER CONTRIBUTIONS TO GENERAL GEOLOGY, 1920. 

The genus Glycimeris, usually described as 

Pedunculus or Axinaea, forms a somewhat conspicuous feature of the Ripley fauna of the 

Gulf and Atlantic Coastal Plain, but in the Cretaceous of the region of the Great Plains and 

Rocky Mountains it has been found at but few 

localities, and only two other species have been 

described-G. wyomingensis (!\feek), from the 

1\fesaverde formation on Cooper Creek, Laramie Plains, and G. holrnesiana (White), from 

the same formation at Point of Rocks, Wyo. 

G. u:ryomingensis does not differ greatly in general appearance from G. subimbricata, but it is 

a heavier, somewhat more convex shell, with 

relatively broader though less conspicuous radiating ribs. 

Locality and position: The published descriptions state that the types came from Heart 

River in the "upper part of the Fox IIills beds," 

but it is now known that all the marine deposits 

on Heart River are in the Cannonball marine 

member of the Lance formation. The type 

specimens are catalogued and labeled (probably 

incorrectly) as from Long Lake, which is a Fox 

Hills locality. The species has not sirice been 

found at any true Fox Hills locality, but 

it has been found in the Cannonball member at six localities distributed over a considerable area ranging from T. 132 N. toT. 

139 N. and from R. 82 W. to R. 88 W. 

in North Dakota. The specimens figured are 

from theSE. l sec. 11, T. 136 N., R. 82 W., 5 

miles southeast of Strain, N. Dak. (fig. 6), and 

from sec. 11, T. 132 N., R. 88 W., in the valley 

of Cannonball River about 7 miles south of 

Leith, N. Dak. (fig. 7). 

Family PERNIDAE. 

Genus PEDALION Solander. 

Pedalion lloydi Stanton, n. sp. 

Plate IV, figures 1a, lb, and 2. 

Perna sp. Stanton, Geol. Soc. America Bull., vol. 25, 

p. 352, 1914. 

Shell of moderate size, compressed/ elongate 

subovate, with acute terminal beak; test very 

thick, especially near the middle of the hinge; 

hinge area relatively broad, with numerous 

shallow cartilage grooves which are slightly 

broader than the spaces between them; surface 

marked only by inconspicuous lines of growth. 

Height, about 95 millimeters; length, about 

49 millimeters; thickness of test in fragment represented by figure 2, 15 millimeters. 

The fragmentary material on which thil 

species is based evidently belongs to the genus 

best known as Perna or Melina, for which W. 

H. Dall has revived the earlier name Pedalion. 

The genus ranges from the Triassic to the Recent· 

seas and is represented by several species in 

American Cretaceous and Tertiary formations. 

This is the first record of its occurrence in the 

region of the Great Plains and Rocky Mountains 

but it is represented by another undescribed 

species in the Frontier formation of the Wind 

River region. The species is abundant at the 

type locality in a layer of soft, friable sandstone 

about a foot thick. On account of the fragile 

character of both the shells and the matrix it 

has not been practicable to collect' specimens 

showing the complete form and the restored 

outline may not be strictly accurate, but the 

fragmentary shells in the collection show that 

it differs in details of outline and other features 

from all the described American species. 

The specific name is given in honor of Mr. E. 

Russell Lloyd, of the United States Geological 

Survey, who collected the first specimens. 

Locality and position: The types were collected in the lower part of the Cannonball marine member of the Lance formation in sec. 13, 

T. 132 N., R. 88 W., on the south bank of Cannonball River about 1 mile west of J anesburg, 

N. Dak. Specimens have also been found a 

quarter of a mile south of Janesburg, and at 

another locality about 15 miles east, near Schaller post office. 

Family PTERIIDAE. 

Genus PTERIA Scopoli. 

Pteria linguaeformis (Evans and Shumard). 

Pl~te III, figure 1. 

A 'vicula linguaejormis Evans and Shumard, A cad. Nat. 

Sci. Philadelphia Proc., vol. 7, p. 153, 1854. 

Meek, in Hind, Report on the Assiniboine and Saskatchewan exploring expedition, p. 183, pl. 1, fig. 

6, 1859. 

Pteria linguiformis (Evans and Shumard) Meek, Check list 

of invertebrate fossils of North America, Cretaceous 

and Jurassic, p. 9, 1864; U. S. Geol. Survey Terr. 

Rept., vol. 9, p. 32, pl. 16, figs. 1 a-d, 1876. 

'\"\-"'hitfield, in Newton and Jenney, Geology and resources of the Black Hills of Dakota, p. 384, pl. 7 

figs. 2, 3, 1880. 

Whiteaves, Contr. Canadian Paleontology, vol. 1, p. 

31, 1885. 

Pteria petrosa (Conrad) Weller, New Jersey Geol. Survey, 

· Paleontology, vol. 4, p. 429, 1907. 

This species, which is so widely distributed 

in the Pierre shale and the Fox Hills sand-
FAUNA 0~' CANNONBALL MARINE MEMBER OF LANCE·FORMATION. 25 

stone, is very rare in the Cannonball fauna. 

The specimen figured was collected in the 

SW. i sec. 30, T. 130 N., R. 88 W., in North 

Dakota, 7 miles north of Morristown, S. Dak. 

Another specimen was found on Heart River 

three-quarters of a mile west of Mandan, 

N. Dak., in the upper part of the Cannonball 

marine member of the Lance formation. 

Weller treats P. linguaejormis as a synonym 

of P. petrosa, which Conrad described in 1853 

from an imperfect specimen collected along the 

Chesapeake & Delaware Canal. P. petrosa 

has been described and figured from New 'Jersey specimens (also imperfect) by both Whitfield and Weller. Although it is obviously related to the western form, the published figures of P. petrosa do not seem to justify the 

application of the same name to P. linguaeformis. 

Genus MODIOLUS Lamarck. 

Modiolus sehallerensis Stanton, n. sp. 

Plate III, figure 6. 

Shell small, elongate ovate in outline, moderately convex; beak nearly terminal, not conspicuous; dorsal margin straight or very 

beaks; short dorsal margin behind the beaks 

almost straight and descending slightly to its 

subangular junction with the broadly rounded 

posterior margin; anterior margin also broadly 

rounded, base more narrowly rounded; surface 

marked by numerous fine radiating lines, which 

are vi5ible under a lens on well-preserved internal casts, and by very fine growth lines and 

more distinct and somewhat irregular concentric furrows. 

Height. from beak to base, 14 millimeters; 

greatest breadth, 12 millimeters; convexity of 

both valves, 9 millimeters. 

This species is related to 0. elegantula Meek 

and Hayden, but it is a stouter shell and differs 

in other details of outline. The radial sculpture 

also is less distinct, at least on the internal 

casts. 

Locality and position: The types were collected in the·Cannonball marine member of the 

Lance formation on Cedar Creek, N. Dak., in 

the SW. i sec. 30, T. 130 N., ·R. 88 W., 7 miles 

north of Morris~own, S. Dak. Another specimen was found near the top of the Cannonball 

member on Heart River three-quarters of a 

mile west or Mandan, N. Dak. 

broadly convex; ventral margin distinctly Crenella elongata Stanton, n. sp. 

arcuate near the middle; posterior end regu- Plate II, figures Sa and Sb. 

larly rounded; anterior end subtruncate; sur- Shell large, elongate · subovate in outline, 

face. marked by numerous fine radiating lines moderately convex, with prominent incurved 

which become coarser and tend to bifurcate beaks; dorsal margin descending rapidly with a 

toward the posterior end. broad .curve into the nearly straight posterior 

Length, 5 millimeters; greatest breadth, 7 margin; basal margin somewhat. narrowly 

millimeters; convexity of both valves,. about 6 rounded; anterior margin broadly convex 

millimeters. · below, excavated above under the beak; surface 

The species is represented by nine specimens with very fine radiating lines, which are obsoof approximately the same size from a single lete on the cast and the exfoliated shell, and 

locality. Their small size suggests that they ·with finer lines of growth and other concentric 

may be immature. In outline the species re- markings. 

sembles M. meeki (Evans .and Shumard)' from Height from beak to base, 25 millimeters; 

the Fox Hills; in sculpture it is more like M. greatest breadth, 15 millimeters; convexity of 

regularis (White), from the Laramie. both valves, about 14 millimeters. 

Locality and position: One mile west of This species differs from 0. cedrensis in its 

Schaller post office, N. Dak., in the NW. i sec. larger size, more slender and less convex form, 

22, T. 132 N., R: 85 W., near the base of the and less pronounced radial sculpture. It, is 

Cannonball marine member of Lance forma- even more slender than 0. elegantula, from which 

tion. Genus CRENELLA Brown. it differs in all other details. 

Locality and position: The type, which is Crenella eedrensis Stanton, n. sp. slightly distorted by pressure, was collected in 

Plate II, figures 9a-9c. the upper part of the Cannonball marine memShell of moderate size, broadly subovate in ber of the Lance f.ormation in a bluff on the 

outline, very convex, with prominent incurved west bank of Missouri River 1 mile south of 
26 SHORTER CONTRIBUTIONS TO GENERAL GEOLOGY, 1920. 

Price and 19 miles north of Mandan, N. Dak. found in several of the Upper Cretaceous 

Some small specimens which may be immature formations of New Jersey and in the Ripley of 

individuals of this species were obtained on the ~fississippi. In my opinion that species also is 

north fork of Grand River in the SW. i sec. 11, a Pholadomya. 

T. 21 N., R. 14 E., 10 miles south of White Locality and position: The type was colButte, S.Dak. lected 3! miles west of Haley, N.Dak., at the 

Family PHOLADOMYACIDAE. 

Genus PHOLADOMYA Sowerby. 

Pholadomya haresi Stanton, n. sp. 

Plate III, figures 2a, 2b, and 3. 

Shell small, transversely subovate in outline, 

very convex in umbonal region of anterior 

third but narrowing and flattening somewhat 

rapidly toward posterior end; beaks prominent . . ' approXlillate, situated about one-third of the 

length from the anterior end, a sub angular 

umbonal ridge descending from the beaks with 

a slight forward direction almost to the ventral 

margin; posterior end slightly gaping and narrowly rounded; anterior end broadly rounded 

and closed, though the type specimen, probably 

on account of accidents in preservation, has an 

apparent anterior gape; surface (of the cast) 

with about eight relatively strong radiating 

ribs on the anterior third, with more obscure 

radiating lines on the middle third, and with 

moderately strong but irregular concentric 

sculpture over the entire surface. 

Length, 26 millimeters; height, 18 millimeters; 

greatest convexity of both valves, 18 millimeters. Another fragmentary specimen indicates dimensions about one-third larger. 

The species is named for Mr. C. J. Hares, 

who collected the types. When first examined 

it was identified as Pholas sp. and was so recorded in Lloyd and Hares's paper on the 

Cannonball marine member of the Lance formation.1 On further study it seems to be referable to Pholadomya and to belong to the same 

group with P. semicostata Agassiz, of the 

European Lower Cretaceous. In form and 

sculpture it also has considerable resemblance 

to P. mauryi Harris, 2 from beds of Midway age 

in Tennessee, but it differs in its more pronounced anterior umbonal ridge, straighter 

ventral margin, and narrower posterior end. 

Except in details of sculpture it does not differ 

greatly from Pholas cithara ~{orton, which is 

1 Jour. Geology, vol. 23, p. 533, 1915. 

2 Harris, G. D., The Midway stage: Bull. Am. Paleontology, vo!. 1, 

p. 158, pl. 6, fig. 17. 1896. 

common· quarter corner of sees. 21 and 28. T. 

129 N., R. 100 W. The only other specimen, 

which is also figured, was collected on the· 

south hank of North Fork of Grand River a 

quarter of a mile east of Bloom, S. Dak., in Rec. 

24., T. 23 N., R. 9 E. The two localities are 

about 12 miles apart and in the Cannonball 

marine member of the Lance formation. 

Family ANATINIDAE. 

Genus ANATINA Lamarck. 

Anatina subgracilis (Whitfield). 

Plate III, figures 4a, 4b, 5a, and 5b. 

Thraeia subgraeilis Whitfield, Preliminary report on the 

paleontology of the Black Hills, p. 36, 1877; in 

Newton and Jenney, Geology and resources of the 

Black Hills of Dakota, p. 419, pl. 11, figs. 29, 30, 

1880. 

Thracia sp. Stanton, Geol. Soc. America Bull., vol. 25, 

p. 352, 1914. ' 

Shell small, transversely subovate, moderately convex, almost equivalve, the portion 

behind the beaks more compressed and much 

smaller than the rest of the shell, slightly 

gaping at posterior end; beaks rather prominent, transversely fissured, directed backward, 

and situated considerably behind the middle; 

dorsal margin gently convex in front· of the 

beaks and slightly concave behind; anterior 

end broadly rounded; posterior end narrower 

and subtruncate; ventral margin broadly and 

regularly rounded in the anterior two-thirds ' nearly straight and more rapidly ascending in 

the posterior third; test thin and nacreous · - ' surface marked by somewhat irregular concentric ribs or undulations and-by fine lines of 

growth, all of ~hich are about as conspicuous 

on the internal cast as on the exterior of the 

shell itself. 

Length of type specimen, 20 millimeters; 

height, 15 millimeters; convexity of both valves 

7 millimeters. The corresponding measure~ ments of a specimen in the Cannonball fauna 

are 24, 18, and 9 millimeters, respectively. 

In referring this species to Throcia Whitfield 

compared it with T. gracilis Meek and Hayden, 
FAUNA OF CANNONBALL MARINE MEMBER OF LANCE FORMATION. 27 

but the fissured beaks, which he described and 

figured, and other features preserved differ 

from those of Thracia and agree better with 

.Anatina, to which it is here referred. Thracia 

gracilis is apparently a true Thracia. 

The best preserved of the three specimens 

found in the Cannonball member agree in every 

detail with the type of the species except that 

the type is smaller and its ventral margin, as 

described by Whitfield, is ''constricted or sinuate behind," a feature which is obviously caused 

by an accidental break.. 

Locality and position: The type (fig. 4) 

came from the Pierre shale (probably upper 

part) on Cheyenne River near French Creek, 

S. Dak. In the Cannonball marine member of 

·the Lance formation two specimens, one of 

which is figured, were found 7 miles southwest 

of Lemmon, S. Dak. ; another was obtained in 

a high bluff in the SW. l sec. 5, T. 129 N., 

R. 89 W., south of Cedar Creek, N. Dak., and 

three others 3! miles west of Haley, N. Dak. 

Family PLEUB.OPHOB.IDAE. 

Genus AB.CTICA Schumacher. 

Aretica ovata (Meek and Hayden). 

Plate IV, figures 4, 5, 6a, and 6b. 

Cyprina ovata Meek and Hayden, Acad. Nat. Sci. Philadelphia Proc., vol. 9, p. 144, 1857. 

Meek, U. S. Geol. Survey Terr. Rept., vol. 9, p. 146, 

pl. 29, figs. 7 a-c, text fig. 8, 1876. 

Whiteaves, Contr. Canadian Paleontology, vol. 1, 

pt. 1, p. 40, 1885; pt. 2, p. 175, 1889. 

Cyprina compressa Meek and Hayden, Acad. Nat. Sci. 

Philadelphia Proc., vol. 9, p. 144, 1857. 

Cyprina ovata var. compressa Meek, U. S. Geol. Survey 

Terr. Rept., vol. 9, p. 147, pl. 30, fig. 11, 1876. 

Meek's description: 

Shell transversely ovate, compressed or moderately 

convex, rather thin; extremities somewhat narrowly 

rounded; basal margin semioval; dorsal border declining 

with a gently convex outline posteriorly and more abruptly 

in front; beaks not much elevated, rather small, moderately oblique, and located about halfway between the 

middle and the anterior end; surface marked hy distinct 

lines of growth. 

Length, 2.35 inches [57.15 millimeters]; height, 1.95 

inches [49.53 millimeters]; convexity, 1.15 inches [29.21 

millimeters]. 

Meek called attention to the very close agreement of the hinge of this species with the hinge 

of the recent species .A. islandica, which leaves 

no doubt concerning the reference to the genus 

Arctica, more commonly called Oyprina. 

The specimen that was described as a distinct 

species under the name Oyprina compressa 

(fig. 5) and later classified as a variety of 

ovata does not differ enough from the type to 

warranteven varietal separation. Meek says: "It 

agrees with the species in all respects, excepting 

in the greater elevation and more nearly central 

position of its beaks, which are also a little less 

oblique," but even these apparent differences 

are partly due to incorrect posing of the imperfect internal cast. The outlines of the two 

specimens are almost exactly of the same shape, 

and the difference in ratio of height to length is 

less than 1 per cent. Meek states in his final 

publication that the two shells were found associated at the mouth of Heart River, but on 

account of an obvious blunder in the arrangement of the paper containing the original descriptions the type of the variety compressa has 

been credited to the Fox Hills sandstone on 

Moreau River. The description of Oyprina 

compressa should have followed that of 0. 

ovata. Then the statement that the locality 

and position are "same as last" would have 

correctly indicated the mouth of Heart River. 

Locality and position: The type locality, as 

above indicated, is at or near the site of the 

present town of Mandan, N. Dak., and is now 

known to be in the upper part of the Cannonball marine member of the Lance formation. 

The species is common in the bluffs on the 

north side of Heart River 1 mile west of Mandan. The hinge of~ left valve represented by 

figure 4 was obtained near the top of Mitchell 

Butte, 3 miles east of Flasher, N.Dak. Other 

localities are the site of old Fort Lin,coln, 4 

miles south of Mandan; 3 and 5 miles east of 

Strain, in T. 136 N., R. 82 W.; 6 miles east of 

Flasher; 7 and 8 miles northwest of Solen; and 

Heart River 10 miles north of Flasher, all in 

the Cannonball marine member of the Lance 

formation. 

Whiteaves reports both the typical form and 

a variety, which he named alta, as abundant at 

many localities in Alberta ia the formation now 

known as the Bearpaw shale. Through the 

courtesy of the Geological Survey of Canada I 

have examined five specimens of the variety 

alta from Ross Coulee, South Saskatchewan, 

and 5 miles above Swift Current, Belly River, 

St. Marys River, and Bow River, Alberta. The 

specimens (internal casts) from the first two 

localities have almost the proportions of typical 
28 SHORTER CONTRIBUTIONS TO GE.NERAL GEOLOGY, 1920. 

C'. ovata except that the valves are slightly Meek's description: 

more convex and the posterior end is not quite 

so broadly rounded. The other specimens are 

relatively higher, having the form of Whiteaves's figure of the variety alta. All are larger, 

and most very much larger, than any that have 

been found in the Cannonball member. I have 

not been able to see any of the Canadian specimens referred to the typical form of the species. 

Family ASTARTIDAE. 

Genus ERIPHYLA Gabb. 

Eriphyla? mandanensis Stanton, n. sp. 

Plate IV, figure 3. 

Shell very small, relatively thick, rounded 

subtrigonal in outline; with length and height 

almost equal; anterior side rounded below and 

slightly concave above; posterior side more 

broadly rounded; base forming a regular curV-e· 

beaks prominent, located a little in front of th~ · ~iddle. Surface ornamented by fine growth 

hnes and about seven broad, concentric ribs 

separated by much narrower grooves. Hinge 

and other internal characters not seen. 

Length and height each, about 5 millimeters· . ' convexity of both valves, about 3 millimeters. 

This species is of about the same size as the 

upper Pierre species E. gregaria Meek and 

Hayden, from which it may be distinguished 

by its relatively greater height and especially 

by its much coarser and less numerous concentric ribs. 

Locality and position: Near top of bluff on 

Heart River about a mile west of Mandan 

N. Dak., in the upper part of the Cannonball 

marine member of the Lance formation. 

Family CRASSATELLITIDAE. 

Genus CRASSATELLITES Kruger. 

Crassatellites evansi Hall and Meek. 

Plate III, figure 7a-9. 

Crassatella evansii Hall and Meek, Am. Acad. Arts and Sci. 

Mem., new ser., vol. 5, p. 383, pl. 1, figs. 9 a-e, 1856. 

Crassatella (Pachythaeru§l) evansi (Hall and Meek) Meek, 

U.S. Geol. Survey Terr. Rept., vol. 9, p.ll7, pl.17, 

figs. 6 a-d, 1876. 

Astarte evansi Whitfield, in Newton and Jenney, Geology 

and resources of the Black Hills of Dakota, p. 413, 

pl. 11, fig. 131, 1880. 

Cf. Cytherea missouriana Morton, Acad. Nat. Sci. Philadelphia Jour., 1st ser., vol. 8, p. 210, pl. 11, fig. 2, 1842. 

Shell ovate-sub trigonal, rather gibbous thick~ anterior 

side obliquely truncated and generally a llttle c~ncave in 

outline above and abruptly rounded below; base semiovate, being usually slightly more prominent before than 

behind the middle; posterior side longer than the other 

sloping from the beaks above, and rounded or verticall; 

subtruncate at the extremity; lunule oval, ther deep; 

escutcheon narrow lanceolate, defined by an o scure ridge 

o~ ~ch ~ide; :gallial margins regularly and ely crenate 

Within; beaks prominent, gibbous, and locat about halfway between the middle and the anterior extr mity. Surface marked by fine, irregular lines of growt , which are 

sometimes gathered into small, obscure wrin les near the 

borders; muscular and pallial impressions stro gly marked. 

I.ength, 1 inch [25.4 millimeters]; height, 0. Oinch [22.8 

millimeters]; convexity, 0.71 inch [18 millim tersJ. 

The original types described by Hall and 

Meek were somewhat larger, the mea urements 

recorded being length 1.4 inches, h ight 0.97 

inch, and convexity 0. 70 inch. · Th best-preserved specimen from the Cannonba member 

measures 33 millimeters in length, 28 millimeters in height, and 19 millimete in convexity. Other imperfect specimens la.re somewhat larger. f, 

Although there is slight variation n propor-

~ions the 20 specimens representing six localities in the Cannonball member are referred 

without question to 0. evansi. · 

Morton's figure of Cytherea missouriana resembles this species closely enough to cause a 

~uspicion that it may be identical, and if the 

Identity could be established the earl~er specific 

name missouriana should be used, . but with 

only Morton's obviously inaccurate! figure for 

comparison a change of name is not justified. 

Locality and position: The types came from 

the upper part of the Pierre shale on Cheyenne 

River at the mouth of Sage Creek, S.Dak., and 

the specimens figured by Meek came from the 

same position and nearly the same locality. 

In the Cannonball marine member of the Lance 

formation the species was collected in T. 133 

N., R. 88 W., about 6 miles south of Kayser, 

N.Dak. (figs. 7a, 7b); in the NE. i sec. 3, T. 

134 N., R. 83 W. (:fig. 9); about 20 feet below 

the top of the plateau 6 miles east of Flasher, 

N. Dak. (fig. 8); 9 miles southwest of Leith, 

N.Dak., 7 miles southeast of Kayser, N.Dak.; 

7 miles southwest of Pretty Rock, N. Dak.; and 

on Heart River, about 12 miles south of Almont, 

N.Dak., on the south line of sec. 20, T. 136 N., 

R. 86 W. 
FAUNA OF CANNONBALL MARINE MEMBER OF LANCE FORMATION. 29 

Family CYRENIDAE. Corbieula berthoudi White. 

Genus CORBICULA :Megerle. Plate V, figures 1a-3. 

Corbicula cytheriformis Meek and Hayden. n J.:-.z b tho-·.:~· Whi u s N t M Proc I vOTuwu a e:r u,u,t te, . o a o US. # ., VO o 

Plate v, figures 4a and 4b. 5, p. 94, pl. 4, figs. 1-3, 1882; U. S. Geol. Survey 

Third Ann. Rept., p. 438, pl. 21, figs. 1-3, 1882. 

Cyrena ( Corbicula%) cythe:rijormis Meek and Hayden, A cad. 

Nat. Sci. Philadelphia Proco, vol.12, p.176, 1860. Original description: 

Corbicula cythe:riformis Meek, U. S. Geol. Survey Terr. Shell very large, subtrigonal in marginal outline, modRe.pt., vol. 9, P· 520, pl. 40, figs. 5 a-c, 1876. erately gibbous; nont concave immediately in front of 

White, U. S. Geol. and Geog. Survey Terr. Twelfth the beaks; front margiJI regularly rounded; basal margin 

Ann. Rept., pt. 1, P· '74, pl. 21, figs. 4a-d, 1880; broadly rounded; postero-basal margin abruptly rounded 

U. S. Geological Survey Third Ann. Rept., p. 437, up to the postero-dorsal margin, which latter margin 

pl. 22, figs. 1-6, 1883. slopes obliquely downward with a gentle convexity from 

Sta.nton, U. S. Geol. Survey Prof. Paper 98, p. 316, between the beaks; hinge strong; all the teeth well depl. 82~ fig. 4, 1916. veloped, the lateral ones especially being long and large 

Meek's description: and crenulated upon their edges, as is usual with all the 

known species of Corbicula of the Lara'mie group; muscular 

Shell attaining a large size, transversely ovate-sub- and pallial impressions having the usual characteristics; 

trigonal or varying to subcircular but always a little longer surface marked with the usual concentric lines. 

than high, moderately convex, rather thick and strong; Length of one of the largest examples in the collections, 

extremities more or less rounded, or the posterior some- 62 millimeters; height from base to umbo, 54 millimeters; 

times faintly subtruncated; basal outline forming a semi- thickness, both valves together, 44 millimeters. 

ovate curve, the most prominent part of which is generally This fine large species, the largest yet known in North 

in advance of the middle; dorsal margin sloping unequally America, has been found only in the Laramie strata east 

from the beaks, the anterior slope being more abrupt and of the Rocky Mountains in Colorado. tt is named in 

slightly concave in outline, and the posterior convex; honor of Capt. E. L. Berthoud, .the first discoverer of the 

beaks moderately prominent and placed more or less in· rich shell deposits of the Laramie group in that region. 

advance of the middle; surface only marked by lines of 

growth, without distinct concentric furrows. The locality is given as ''valley of South 

Length of a medium-sized rather transverse specimen, Platte River, northeastern Colorado," but the 

1.20 inches [30.5 millimeters]; h_eight, 1.05 inche8 [26.67 type specimens in the National Museum are 

millimeters]; convexity, 0.77 inch [18.5 millimeters]. more definitely labeled "15 miles north of FreThe specimens from the Cannonball member monts Orchard, valley of South Platte, Coloagree in every detail with the type, which came rado." Fremonts Orchard is presumably the 

from the Judith River formation. (Compare same as Orchard station on the Julesburg 

fig. 4a, which is a photograph of the best- branch of the Union Pacific Railroad. This 

preserved shell, with Meek's fig. 5a, which is is the only locality from which the species has 

drawn from the type specimen.) Associated been recorded, and its presence in the Cannonwith the figured specimen are numerous others ball fauna was not suspected until careful prepof about the same size and a few that are much aration of the hinges of some specimens that 

larger. had been referred to Veniella (~).showed that 

Locality and position: In the Cannonball they belong to OorbicUla. Direct comparison 

marine member of the Lance formation the of these specimens with the types of Oorbicula 

species is common in the NW.! sec. 22, T. 132 berthoudi showed so close an agreement in size, 

N., R. 85 W., 1 mile west of Schaller post office, form, sculpture, and hinge character that I 

N. Dak. A few additional specimens were have no hesitation in referring them to the 

obtained on the site of old Fort Lincoln, 4 same species, though its associates at .the North 

miles south of Mandan, N. Dak. The types Dakota localities are all marine while in Colocame from the Judith River formation near rado they are brackish-water forms. · 

Judith, Mont., and the species occurs in the Locality and position: The specimens figMesaverde formation of southern Wyoming, in ured were collected in the NW. l sec. 11, 

theBlackButtescoalgroupofthesameregion, T. 132 N., R. 88 W., about 7 miles south of 

and in the lower part of the Fruitland forma- L~ith, N. Dak., and on the west bank of Mistion in San Juan County, N.Mex. Closely re- souri River 1 mile south of Price and 19 miles 

lated forms are also found in the Laramie for- north of Mandan, N. Dak., in the Cannonball 

mation of northeastern Colorado. marine member of the Lance formation. Other 

43595°-21-3 
30 SHORTER CONTRIBUTIONS TO GENERAL GEOLOGY, 1920. 

specimens were obtained in the SE. i sec. 11, 

T. 22 N., R. 19 E., 4 miles south of Morristown 

S.Dak. ' 

Family LUCINIDAE. 

Genus LUCINA BruguH~re. 

Lucina cedrensis Stanton, n. sp. 

Plate III, figures 10a-llb. 

Lueina oceidentalis (Morton). · Stanton, Geol. Soc. America Bull., vol. 25, p. 352, 191A. 

Shell rather large, subcircular, with height 

nearl:y equal to length, moderately convex; 

anterior, basal, and posterior margins forming 

a nearly regular subcircular curve· dorsal ' margin declining slightly in a convex curve 

behind the beak, concave to the end of the 

deeply excavated lunule in front; beaks small, 

nearly median in position; posterior groove 

bordering the posterodorsal margin, rather obscure; hinge with well-developed cardinal and 

anterior lateral teeth, and very small posterior 

lateral tooth; ligament deeply sunken, border~d interiorly by a conspicuous ridge which 

simulates a third cardinal tooth. Surface 

maPked by very fine, closely arranged concentric lines. Exfoliated specimens also ·show 

rather prominent radiating lines on the inner 

laminae of the shell. 

Length of type, 39 millimeters; height, about 

36 millimeters; convexity of both valves about 

18 millimeters. A larger specimen from ~nother locality believed to belong to the same species 

is about 45 millimeters in length, 4 7 millimeters in height, and 24 millimeters in convexity 

of both valves. 

This species is of about the size of L. occidentalis (Morton), and in preliminary lists of 

the Cannonball fauna it was referred to that 

species. It may be distinguished from L. occidentalis by its greater proportional height, 

smoother surface, and shorter and mY.ch more 

deeply excavated lunule. 

Locality and position: The type (fig. 10) 

was obtained north of Cedar River in the 

NW. i sec. 9, T. 130 N., R. 90 W., about 10 

.. miles southwest of Pretty Rock, N.Dak. The 

other figured specimen and three others were 

collected in sec. 7, T. 4 N., R. 83 W., near the 

top of Mitchell Butte, 3 miles east of Flasher, 

N. Dak. Another specimen possibly belonging 

to the same species was found in T. 133 N., R. 

88 W., about 6 miles south of Kayser, N.Dak. 

All these localities are in the Cannonball 

marine member of the Lance formation. 

Family VENERIDAE. 

Genus CALLISTA Poli. 

Callista (Dosiniopsis) nebrascensis (Meek and Hayden). 

Plate V, figures 5-10. 

Cytherea nebrascensis Meek and Hayden, Acad. Nat. Sci. 

Philadelphia Proc., vol. 8, p. 83, 1856. 

Dione nebrascensis Meek, Check list of invertebrate fossils 

of North America, p. 13, 1864. 

Callista (Dosiniopsis) nebrascensis Meek (in part), U. S. 

Geol. Survey Terr. ltept., vol. 9, p. 184, 1876 .. 

. Probably not the figured specimens. 

Originai description: 

Shell subcircular, much compressed; beaks somewhat 

elevated, small, a little in advance of the center; ligamentary cavity long and very narrow lanceolate; surface 

marked with rather faint lines of growth. 

Length 0.70 inch [17.78 millimeters]; breadth 0.28 inch 

[7.11 millimeters]; height 0.60 inch [15.24 millimeters]. 

The much more compressed form of this shell will serve 

to distinguish it at once from the last [C. deweyt]. 

Locality and position: Moreau River, No.5 of the series 

[that is, Fox Hills]. 

The type, which is represented by figure 8, 

has never before been figured. It is labeled in 

Meek's handwriting "Cretaceous 4 (upper), 

Cheyenne and Moreau rivers, 343," and is accompanied by another specimen on which is 

printed "Chey," indicating that it is from 

Cheyenne River. Whether it came from No. 5, 

the Fox Hills sandstone, as stated in the original description, or from the upper part of the 

Pierre shale, as stated on the label and in 

Meek's final publication, the species is certainly abundant in the upper part of the Fox 

Hills sandstone on Cannonball River and in 

neighboring railroad cuts 4 to 5 miles east of 

Solen, N. Dak. 

Most of the more extended description and 

all of the illustrations in Meek's volume last 

cited are based on much larger specimens from 

Deer Creek, on North Platte River in Wyoming, 

which in Meek's opinion "represent only a 

more robust growth of one speoies, 0. nebrascensis, which was founded upon young or less 

developed and slightly more compressed individuals; though it is barely possible that they 

may be distinct." This larger, more convex 

form had previously been separated by Meek 

and Hayden 1 as a distinct species under the 

name Oallista robusta, and it is my judgment 

that this name should be revived. 

At two localities in the Cannonball marine 

member of the Lance formation· 0. nebrascensis 

1 Acad. Nat Sci. Philadelphia Proc., vol. 13, p. 443, footnote, 1861. 
FAUNA OF CANNONBALL MARINE MEMBER OF LANCE FORMATION. 31 

is a common species. The specimens are not 

as Wf'll preserved as those from the Fox Hills, 

but s9 far as can be determined from direct 

comparison they agree in shape, sculptlll'e, 

and details of the hinge. The localities are a 

bluff on the north side of Heart River 1 mile 

west of Mandan, N.Dak., and the west bank 

of Missouri River 1 mile south of Price and 

19 miles north of Mandan. At the latter 

locality it is associated with 0. deweyi. It was 

also collected 1 mile west. of Schaller post 

office, N. Dak. 

The generic reference of this and the following species has been left as Meek placed it, 

Dosiniopsis being tr~ated as a subgenus under 

Callista. All questions concerning the validity 

and rank of Dosiniopsis, Callista, Dione, Meretrix, and other names that have been applied 

to these and similar shells are for the present 

held in abeyance, though attention may be 

called to the fact that Woods 1 recognizes 

Dosiniopsis as a distinct genus and that the 

hinge of D. subrotunda (Sower by) as figured by 

him agreeS closely in every detail with the 

hinge of C. (D.) nebrascensis. 

Callista (Dosiniopsis?) deweyi (Meek and Hayden). 

Plate V, figures 11 and 12. 

Cytherea deweyi Meek and Hayden, A cad. Nat. Sci. Philadelphia Proc., vol. 8, p. 83, 1856. 

Meretrix deweyi Meek and Hayden, idem, vol.l2, p.l85, 

1860. 

Callista deweyi Meek and Hayden, idem, vol. 13, p. 143, 

1861. 

Dionedeweyi Meek, Smithsonian check list of invertebrate 

f.ossils of North America, p. 13, 1864. 

Callista (Dosiniopsisf) deweyi Meek, U. S. Geol. Survey 

Terr. Rept., vol. 9, p. 182, pl. 17, figs. 15a-e, 1876. 

Whiteaves, Contr. Canadian Paleontology, vol. 1, pt. 

1, p. 42, pl. 6, figs. 4(?), 5, 5a, 1885. 

Dosinia missouriana? (Morton) Whitfield, in Newton and 

Jenney, Geology and resources of the Black Hills 

of Dakota, p. 416, pl. 11, figs. 25, 26, 1880. 

Not Cytherea missouriana Morton, Acad·. Nat. Sci. Philadelphia Jour., 1st ser., vol. 8, p. 210, pl. 11, fig. 2, 

1842, which is probably a Crassatellites. 

Meek's revised description: 

Shell subcircular, or very broad suboval, rather thin, 

moderately convex; lateral margins rounded, the posterior 

'3ide being a little broader than the other; dorsum sloping 

~adually with a slightly convex outline behind the 

1 Woods, H., :Monograph of Cretaceous Lamellibranchia of England, 

vol. 2, pt. 5, pp. 181, 182, pl. 281908. 

beaks, and concave and more abrupt in front; base semioval; escutcheon lanceolate; beaks not very prominent, 

somewhat gibbous, incurved, nearly touching, and placed 

a little in advance of the ·middle; muscular impressions 

shallow, anterior one narrow oval, posterior one broad 

ovate; sinus of the pallial impression broad, triangular, 

its sides converging at an angle of about 35°, extending 

obliquely forward and upward nearly to the middle of 

the valves, very slightly obtuse at the immediate extremity. Surface marked by fine, regular, prominent lines of 

growth. 

Length, 0.96 inch (24.38 millimeters]; height, 0.83 inch 

[21.08 millim.eters];gibboaity, 0.55i~ch[13.97millimeters]o 

The species originally described from specimens obtained in the Fox Hills sandstone on 

Moreau River is common in that formation 

and in the upper part of the Pierre shale and 

its equivalent. It is especially abundant in 

the Bearpaw shale of northern Montana and 

southern Alberta. The measurements given 

by Meek were taken from a specimen somewhat below the average in size. This type 

specimen is almost exactly duplicated in size, 

form, and all other features preserved by the 

specimens in the· Cannonball fauna here 

figured. 

Whitfield tentatively identified this species 

with Cytherea missouriana Morton and reJerred 

it to the genus Dosinia, but, as Whiteaves 2 

remarks, it is not like Morton's figure and it 

clearly does not belong to Dosinia. Morton's 

figure of Cytherea missouriana has a very 

different outline and shows a deeply excavated 

lunule and a conspicuous escutcheon, in all 

these features strongly suggesting Crassatellites evansi Meek and Hayden. 

Locality and position: In the Cannonball 

marine member of the Lance formation the 

species is common on the west bank of Missouri River 1 mile south of Price and 19 miles 

north of Mandan, N. Dak., where the figured 

specimens were collected. It was also obtained in sec. 28, T. 133 N., R. 88 W., about 

7 miles south of Kayser, N.Dak., and at two 

localities on the North Fork of Grand River 

3! miles west of Haley, N.Dak., and a quarter 

of a mile east of Bloom, S. Dak. Imperfect 

specimens not so positively identified were collected 6 miles east of Flasher, 5 miles southeast of Strain, and 6 miles northwest of Solen, 

N. Dak., and 1 mile east of Morristown, 

S.Dak. 

11 Op. cit., p. 43. 
32 SHORTER CONTRIBUTIO~S TO GENERAL GEOLOGY, 1920. 

Family CORBULIDAE. 

Genus CORBULA Lamarck. 

Corbula mactriformis Meek and Hayden. 

Plate VI, figures 1-2b. 

Corbula mactrijormis Meek and Hayden, Acad. Nat. Sci. 

Philadelphia Proc., vol. 8, p. 117, 1856. 

Meek, U. S. Geol. Surv~y Terr. Rept., v~l. 9, p. 528, 

pl. 43, figs. 7a-f, 1876. 

White, U. S. Geol. and Geog. Survey Terr. Twelfth 

Ann. Rept., pt. 1, p. 80, 1880; U. S. Geol. Survey 

Third Ann. Rept.,· p. 442, pl. 18, figs. 12-15. 

Whiteaves, Contr. Canadian Paleontology, vol. 1, 

pt. 1, p. 27, 1885. 

Corbula (Potamomya) mactrijormis Meek and Hayden, 

Acad. Nat. Sci. Philadelphia Proc., vol. 12, p. 

432, 1860. 

Meek's description: 

Shell ovate-sub trigonal, moderate~y convex; right valve 

a little shorter, thicker, and more gibbous than the other; 

anterior side of both valves obliquely subtruncated, 

slightly concave in outline above and narrowly rounded 

into the base below; posterior side longer, and narrowing 

toward the extremity, which is narrowly rounded, or 

very obscurely subtruncated, base semiovate, being most 

prominent a little in front of the middle; beaks rather 

elevated, poin~d, and incurved with a forward obliquity; 

posterior umbonalslopes h~ving an obscure ridge extending obliquely from the beaks to the pootero-basal margin; 

surface ornamented by moderately distinct lines of 

growth, which are most strongly defined behind the 

oblique umbonal ridge. 

Length, 0.64 inch [16.25 millimeters]; height, 0.54 inch 

[13.7 millimeters]; breadth, about 0.34 inch [8.6 millimeters]. 

Locality and position: The types were collected at Fort Clark, N. Dak., and have 

usually been assigned to the Fort Union formation, though it is now known that the Cannonball marine member of the Lance formation 

extends up Missouri River about to that point. 

The species has been collected near the top 

of the high butte 1 mile south of Price and 

19 miles north of Mandan, N. Dak., in supposed basal beds of the Fort Union, where it 

is associated with Vivipa'T"UB leai, Oampeloma 

multilineata, and Thaumastus limnaeiformis, 

and at about the same horizon and with the 

same associates at several other localities in 

North Dakota. The specimens here figured 

are from the Cannonball marine member of 

the Lance formation in the NW. l sec. 22, T. 

132 N., R. 85 W., 1 mile west of Schaller post 

office, N.Dak., where this species is associated 

with Pedalion? sp., Modiolus schallerensis, Oorbicula cytheriformis, and Oallista (Dosiniopsis) 

nebrascensis. 

Small specimens of Oorbula which may be 

young of this species or possibly represent one 

or two distinct species were collected at several 

other Cannonball localities in North Dakota. 

Family SAXICA VIDAE. 

Genus PANOPE Menard. 

Panope simulatrix Whiteaves1 

Plate VI, figure 3. 

Panopaea simulatrix Whiteaves, Contr; Canadian Paleontology, vol. 1, pt. 1, p. 11, pl. 2, figs. 2, 2a, 1885. 

Tellina sp. Stanton, Geol. Soc. America Bull., vol. 25, p. 

352, 1914. • 

Original description: 

Shell slightly inequivalve, the' umbo of the right valve 

being a little larger and more tumid than that of the left~ 

valves compressed at the sides, thickest on the anterior 

umbonal slope and narrowing very gradually to the posterior end but more rapidly to the anterior; posterior termination gaping; lateral outline elliptic ovate, the length 

being fully twice the maximum height inclusive of the 

beaks, and the posterior side a little longer, narrower, and 

more pointed than the anterior. Umbones broad, obtuse, 

and depressed; beaks small, subcentral, but pl~ed a 

little in advance of the middle, that of the right valve 

curved inward and downward with a slight inclination for• 

ward, that of the left valve curved inward and a little forward but not downward; ligament apparently short and 

externaL Surface concentrically striated; inner layer of 

test not nacreous;. hinge teeth and muscular impressions 

not known. 

Length of the most perfect example collected (the one 

figured), 52 millimeters; greatest height of the same, 2!) 

millimeters; thickness of the same, 16.5 millimeters. 

The type was obtained in the Edmonton 

formation of Alberta, and Whiteaves records 

the species from the approximately equivalent 

St. Mary River formation. Closely related if 

not identical forms are found in the Judith 

River, Laramie, and uppermost Fox Hills or 

basal Lance beds. The hinge has not been seen 

on any of these specimens, but a deep, broad 

pallial sinus has been observed in spooiJ:nens 

from both the Judith River and Laramie formations. Neither the hinge nor the p~llial line 

has been seen on the few specimens found in the 

Cannonball member, but in form and surface 

features they so closely resemble Whiteaves's 

species that they are tentatively referred to it, 

all questions concerning the correctness of the 

generic reference being left. until· better ·material furnishes full details of the hinge and other 

internal features. 

Locality and position: The specimen figured 

and five other less perfect valves wero collected 
FA UN A OF CANNONBALL MARINE MEMBER OF LANCE FORMATION. 83 

in the bluff on the north side of Heart River 1 

mile west of Mandan, N.Dak. A few-imperfect 

casts were obtained on the west bank of Missouri River 1 mile south of Price and 19 miles 

north of Mandt,tn, N. Dak., and 8 miles southeast of Lemmon, S.Dak. All these localities 

are in the Cannonball marine member of the 

Lance formation~ 

Family TEREDINIDAE. 

, Genus TEREDO Linne. 

Teredo selliformis Meek and Hayden. 

. Plate VI, figure 4. 

Teredo sellijormis Meek and Hayden, Acad. Nat. Sci. 

Philadelphia Proc., vol: 12, p. 178, 1869. 

Meek, U. S. Geol. Survey?;err. Rept., vol. 9, p. 262, 

pl. 17, figs. 19 a-d, 1876: · 

Meek's description: 

Shellsubglobose; posterior side narrowly rounded above 

and provided with a broad angular notch below; anterior 

ventral side having a very large hiatus, formed by a similar 

but deeper rectangular notch, which extends from the 

base nearly halfway up to the beaks and back almost to 

the middle of the valves; base between the anterior and 

posterior notches extended downward in the form of a 

narrow prolongation, which curves under and is the only 

part of the ventral borders of the two valves that comes in 

contact; beaks elevated, gibbous, incurved, and located 

between the middle and the anterior margin. Surface 

ornamented by small concentric lines, which are curved 

and deflected parallel to the great irregularities of the free 

borders and croBBed by two radiating grooves, the posterior 

of which paBSes from the back part of the beaks obliquely 

downward and backward to the comer of the posterior 

notch, and the other, which is more distinct, extends almost directly downward to the extremity of the ventral 

prolongation. 

Length of medium-size specimen, 0.16 inch [4 millimeters]; height, 0.14 inch [3.55 millimeters]; convexity, 

0.13 inch [3.3 millimeters]. 

Locality and position: As originally published, "Fort Clark on the Missouri in formation 

No.5," but in Meek's final description the formation is inadvertently given as "Fort Pierre 

group, or formation No. 5," and the figures are 

on a plate with Pierre species. The labels in 

Meek's handwriting read "near Fort Clark." 

It is now known that the only marine beds on 

the :Missouri between Mandan and Fort Clark 

belong in the upper part of the Cannonball 

marine member of the Lanoe formation, ~d the 

specimens of T. selliformis must have come 

from this horizon. The actual type ~pecim.en 

represented by }.{eek's figures 19a and 19b has 

been assumed to be lost because none of the 

specimens in the National Museum are as large 

as figure 19a, which is said to be of natural size. 

On measuring the best-preserved shell, however, it was found that its dimensions agree 

perfectly with the measurements given by 

Meek, though a third smaller than those of his 

figure. It is therefore highly probable that 

this specimen, represented in figure 4, enlarged 

4 diameters, is the type. There are several 

specimens in the type ·lot, including. the tubes 

which were figured. A collection from a bluff 

on the east side of Heart River 12 miles south 

of Almont, N. Dak., consists of numerous 

slender Teredo tubes in which several small 

shells were found whlch are identified as immature specimens of T. selliformis, as they show 

a shallow posterior notch in the ventral margin 

and, on the cast, a wen..:marked posterior 

groove-two features which distinguish this 

species from T. globosa. The species was also 

collected by C. J. Hares in sec. 36, T. 23 N., 

R. 9 E., near Bloom, S. Dak. This lot was 

reported as "burrows of a Teredo-like shell," 

but when some of the burrows were broken up 

identifiable shells were found in sorr1.e of them. 

Teredo globosa Meek and Hay9en. 

Plate VI, figures 5a and 5b. 

Teredo globosa Meek and Hayden, A cad. Nat. Sci. Philadelphia Proc., vol. 10, p. 53, 1858. 

Meek, U.S. Geol. Survey Terr. Rept., vol. 9, p. 264, 

pl. 30, fig. 13, text figs. 31, 32, 1S.76. 

Meek's description: 

Shell globose-cordate, thin; posterior side rounded or 

subtruncated, and not very widely gaping; anterior hiatus 

large, rectangular, extending from the middle of the base 

halfway up the valves; dorsum rounding posteriorly: 

umbonal region gibbous; beaks distinctly incurved obliquely forward, located in advance of the middle. Surface ornamented by concentric lines, which follow the 

curves and angular flexures of the free border and are 

crossed by an obscJll'e, small groove, descending from the 

ooaks. . 

Length, 0.23 inch (5.84 millimeters]; height, 0.24 inch 

[6.1 millimeters]; convexity, 0.22 inch [5.6 millimeters]. 

This species will be distinguished from the preceding 

by the absence of a notch or sinus in the border of its 

posterior side and by having its dorsal margin rounding 

regularly down oohind instead of nearly horizontal. It 

also differs in having no trace of the obscure, oblique 

posterior sulcus on internal casts, and in the annular or 

ringed appearance of its tubes, which are also larger than 

those of that species. 

Locality and position: In origmal description given as "Square Butte, near Fort Clark, 

upper part of No. 5"; in later publication 

"same as last" -that is, Fort Clark. The 
34 SHORTER CONTRIBUTIONS TO GENERAL GEOLOGY, '1920~ 

horizon of the types must have been in the 

upper part of the Cannonball marine member 

of the Lance formation, for the reasons given 

in relation to T. seTliformis. Shells that seem 

to belong to this species, though smaller than 

the type, have been collected on the hill in 

the northern edge of Mandan,· N. Dak.; in a 

bluff on the north side of Heart River, 1 mile 

west of Mandan; and on Mitchell Butte, 3 

miles east of Flasher, N. Dak., all in the Cannonball member. 

Class SCAPHOPODA. 

Family DENTALIIDA_E. 

Genus DENTALIUM Linne. 

Dentalium pauperculum Meek and Hayden. 

Plate VI, figures 6 and 7. 

Dentalium pauperculum Meek and Hayden, Acad: Nat. 

Sci. Philadelphia Proc., vol. 12, p. 178, 1860. 

Entalis? pauperculum Meek, U. S. Geol. Survey Terr. 

Rept., vol. 9, p. 269, pl. 18, fig. 14, 1876. 

Entalis sp. Stanton, Geol. Soc. America Bull., vol. 25, 

p. 352, 1914. 

Meek's description: 

Shell small, 'arcuate, tapering rather gradually; section 

circular; substance comparatively thick; surface smooth 

but showing under a magnifier extremely fine oliscure 

lines of growth, which pass around somewhat obliquely. 

Length of an imperfect specimen, measuring from the 

apex, 0.36 inch [9.14 millimeters]; diameter of same at 

apex, 0.03 inch [0.76 millimeter]; diameter at larger 

extremity, 0.06 inch [1.52 millimeters]. 

Although this smooth arcuate little species 

is not a typical Dentalium, the specimens 

examined, including the type, are not well 

enough preserved to justify its reference to 

any of the described subgenera, and as Entalis 

is now usually either treated as a synonym or 

applied to a group with longitudinal striae it 

seems best to refer this species again to Dentalium until better material is obtained. I 

have not seen ~ specimen in which the posterior end is well enough preserved to show 

whether it has a slit. A slight indication of 

swelling toward the anterior end with contraction at the aperture suggests that it may be a 

Oadulus. 

Meek's figure is misleading because,although 

said to be of natural size, it is almost twice as 

long (17 millimeters) as the type specimen 

(9.14 millimeters). It is also more slender and 

does not show the maximum curvature. The 

type has been prepared by removing more of 

the matrix, and the enlarged figure now given 

is a photograph. 

Locality and position: The type came from 

the Fox Hills sandstone . on Moreau. River, 

S. Dak., associated on the sam~ specimen with 

Scaphites cheyennensis, Yoldia evansi, and 

other typical Fox Hills species. Fragmentary 

specimens from the upper part of the Pierre 

shale on Yellowstone River [near Glendive], 

Mont., were doubtfully referred to the species 

by Meek. Four specimens, one of which is 

figured, were obtained 7 5 feet below the top of 

the Cannonball marine member of the Lance 

formation on Heart River in sec. 10, T. 138 N., 

R. 83 W., about 12 miles southwest of Mandan, 

N. Dak. They seem to agree with the type in 

all particulars. A fragmentary imprint, pos-

~ibly of this species, was collected in the 

SW. -l sec. 15, T. 134 N., R. 86 W., about 4 

miles southwest of Lark, N. Dak. 

Family PYRA:MIDELLIDAE. 

Genus TURBONILLA Risso. 

Turbonilla? cordensis Stanton, n. sp. 

Plate VI, figures Sa and 8b. 

Cerithium sp. Stanton, in Lloyd and Hares, The Cannonball marine member of the Lance formation: Jour. 

Geology, vol. 23, p. 537, 1915. 

Shell small and slender, consisting of seven or 

eight flattened whorls, each of which bears 

about 13 strong longitudinal ribs crossed by 

closely arranged, fine, threadlike spiral lines, of 

which 15 are visible on the penultimate whorl; 

ribs not quite so broad as the interspaoes; base 

rounded and bearing only the spiral lines; 

nuclear whorls not ·preserved; aperture ovate. 

No columellar plication is visible in the aperture nor on the broken whorl near the apex, so 

that if present at all it must be very slightly 

developed, and for this reason the generio 

reference is questioned. 

Height, 11 millimeters; greatest oreadth, 3.5 

:millimeters; height of aperture, 2 millimeters; 

breadth of same, 1.5 millimeters. 

Locality and position: Heart River on the 

south line of the SW. t sec. 20, T. 136 N., R. 86 

W., about 12 :miles south of Almont, N.Dak., 

in the Cannonball marine :me:mber of ~he Lance 

formation, where the single type specimen is 

associated with Orassatellites evansi, Lunatia 

subcrassa, and Anchura americana var. pusilla. 
FAUNA OF CANNONBALL MARINE MEMBER OF LANCE FORMATION. 35 

Family EPITONUDAE. 

Genus EPITONIUM Bolten. 

Epitonium dakotense Stanton, n. sp. 

Plate VI, figures 9a and 9b. 

Scala? sp. Stanton, Geol. Soc. America Bull., vol. 25, p. 

352, 1914. 

Shell of moderate size, with about eight wellrounded rather stout whorls, each of which 

bears about 17low ribs, which are crossed by an 

~qual number of :finer somewhat variable spiral 

hn~; base bounded by a small sub angular 

carina and also bearing :fine spiral lines that are 

not quite as conspicuous as those on the rest 

of the whorl; no umhilicus; ribs not quite as 

?ro~d as the interspaces and varying slightly 

m size, a few of them longitudinally furrowed 

probably indicating a rest stage in growth; 

aperture almost circular with entire peristome. 

-Height, 28 millimeters; greatest breadth 

15 millimeters; diameter of aperture, 7 milli~ meters; apical angle, 30°. 

. This species, which is represented by a 

single well-preserved specimen, has a superficial resemblance in form and sculpture to the 

Fox Hills species Ohemnitzia? cerithiformis 

Meek and Hayden, from which it :may be dis-

~inguished even in fragmentary specimens by 

Its :mo~e regularly rounded whorls, straighter 

and shghtly broader ribs, and :more closely 

arranged spiral lines. The aperture also is 

very different in form. 

Bolten's generic name Epitonium has been 

revived by Dall 1 for the group usually called 

Scalaria or Scala, to which the shell here described obviously belongs. 

Locality and position: From a low bluff on 

Cannonball River in the SW. l sec. 29, T. 133 

N., R. 88_ W., about 6 miles south of Kayser, 

N. Dak., In the Cannonball marine member of 

the Lance formation, associated with Anchura 

amerieana and a few other forms. 

Family NATICIDAE. 

Genus LUNATIA Gray. 

Lunatia obliquata (Hall and Meek). 

Plate VI, figures lOa and lOb. 

Natica obliquata Hall and Meek, Am. Acad. Arts and Sci. 

Mem., vol. 5, p. 389, pl. 3, figs. 1 a, b, 1854. 

Natica moreauensis Meek and Hayden, A cad. Nat. Sci. 

Philadelphia Proc., vol. 8, p. 64, 1856. 

1 Dall, W. H., The Miocene of Astoria and Coos Bay, Oreg.: u. s. Geol. Survey Prof. Paper 59, p. 52, 1909. 

Natica (Lunatia) 'fftfffeauensis Meek and Hayden, idem, 

vol. 12, p. 422, 1860. 

Lunatia moreauensis Gabb, Synopsis of the Mollusca of the 

Cretaceous formation, p. 58, 1861. 

Lunatia concinna Meek, U. S. Geol. Survey Terr. Rept., 

voL 9, p. 314, pl. 32, figs. ll a-c, 1876. 

Cf. Lunatia concinna Hall and Meek, Am. Aead. Arts and 

Sci. Mem., vol. 5, p. 389, pl. 3, figs. 2 a-d, 1854. 

Meek's description: 

Shell obliquely rhombic subovate, or subglobose; spire 

moderate; volutions three and a half to four, convex, and 

separated by a deep suture; last one comparatively large; 

surface marked by fine, rather obscure lines of growth, 

cro_ssed by nearly obsolete, minutely flexuouS, revolving 

stnae, only seen on well-preserved specimens; aperture 

subovate, being straighter on the inner than the outer 

side; umbilicus small and sometimes showing a slight 

tendency to develop a small revolving ridge within; inner 

lip a little thickened and slightly reflected upon the body 

volution above the umbilicus. 

Length of a mature, rather gibbous specimen, 0.90 inch 

[22.8 millimeters]; breadth of same, 0.76 inch [19.3 millimeters]. 

This description and the figures published 

by Meek are drawn from the types of Natica 

moreauensis Meek and Hayden, which Meek 

referred to L. concinna Hall and Meek. Direct 

comparison of these specimens with shells from 

the Cannonball marine member of the Lance 

formation shows very close resemblance in 

every particular except that the Cannonball 

specimens are very slightly stouter and none 

of them is as large as the largest of Meek's 

specimens. The specimen here figured, which 

is one of the largest in the collection, is 15 

millimeters in length and 15 millilneters in 

greatest breadth. The recorded dimensions of 

Hall and Meek's type are length 0.36 inch 

[9.14 millimeters]; breadth 0.32 inch [8.12 

millimeters]. 

I do not doubt the specific identity of the 

Cannonball specimens with Lunatia moreauensis, but there lnay be reason for a difference 

of opinion concerning the name that should be 

applied to them. Meek's :final opinion was 

that L. moreauensis is a synonym of L. concinna, though he also called attention to the 

close relationship with L. obliquata, which 

seemed to differ chiefly in the presence of "an 

opercular groove along the columella." The 

types of L. obliquata and L. concinna are preserved in the .Amerioan Museum of Natural 

History, and through the courtesy of Dr. E. 0. 

Hovey, curator of invertebrate paleontology, 

I have been permitted to examine them and 
36 SHORTER CONTRIBUTIONS TO GENERAL GEOLOGY, 1920. 

to compare them with Meek's figured specimens and with the specimens of Lunatia from 

the Cannonball member. My opinion is that 

t~e Fox Hills specimens which have been called 

L. moreauensis and L. concinna and certain 

of the Cannonball specimens should be referred 

to L. obliquata. The fact that a single Cannonball specimen shows the opercular groove almost as well developed as in the type of L. 

obliquata, while all the others which agree in 

otner features fail to show it, seems to indicate 

that this imprint of the operculum is not of 

specific importance. Meek stated that he had 

sometimes suspected that the original L. concinna should be regarded as belonging to L. 

obliquata, and on the evidence of the description and figures it would be reasonable to make 

this disposition of the species, as the two types 

ar~ so nearly alike, and the description of L. 

obliquata stands first on the page. ~ The status 

of L. concinna is further complicated, however, 

by the fact that the specimen preserved as the 

type of that species is stated by Whitfield and 

Hovey 1 to be " a very young individual of a 

recent form, nqt a fossil." The state of preservation of the specimen, which appears to 

be scarcely at all altered, seems to justify this 

statement, but on the other hand I am assured 

by W. H. Dall and Paul Bartsch that it does 

not belong to any recent species represented in 

the United States National Museum. Furthermore, some undoubted Cretaceous shells 'are 

almost as well preserved. Whether this particular shell is a Cretaceous fossil or not it 

certainly is very closely related to the type of 

L. obliquata. 

Locality and position: The original type 

came from the upper part .of the Pierre shale 

on Sage Creek, S.Dak., and Meek and Hayden's 

specimens described as Natica moreauensis were 

collected in the Fox Hills sandstone on Moreau 

River, S. Dak. The species is represented in 

the collections from 11 localities in the Cannonball marine member of the Lan~ formation as 

follows: 

Sec. 31, T. 133 N., R. 88 W., about 6 miles so~th of 

Kayser, N.Dak. (figured specimens and others). 

Sees. 17 and 28 in same township. 

Sec.ll, T. 22 N., R.15 E., 7 miles southwest of Lemmon, 

S.Dak. 

Sec. 9, T. 130 N., R. 90 W., 10 JD.iles southwest of Pretty 

Rock, N. Dak. 

1 Am. Mus. Nat. Rist. Bull., vol. 11, p. 429, 1901. 

Sec. 17, T. 134 N., R. 81 W., 7 miles northwest of Solen, 

N.Dak. 

Sec. 16, T. 136 N., R. 84 W., on Heart River 10 miles 

north of Flasher, N. Dak. 

Sec. 29, T. 136 N., R. 86 W., 12 miles south of Almont, 

N.Dak. , 

Sec. 19, T. 136 N., R. 87 W., 7 miles southwest of Almont, 

N.Dak. 

Sec. 10, T. 138 N., R. 83 W., on Heart River about 12 

miles southwest of Mandan, N. Dak. 

T. 141 N., R. 81 W., on Missouri River about 1 mile 

south of Price and 19 miles north of Mandan, N ., Dak. 

Lunatia suberassa (Meek and Hayden). 

Plate VI, figures lla and llb. 

Natica sub(JI'assa Meek and Hayden, Acad. Nat. Sci. 

Philadelphia Proc., vol. 8, p. 87, 1856. 

Natica (Lunatia) subaassa Meek and Hayden, id.em; vol. 

12, p. 422, 1860. 

Lunatia sub~assa Gabb, Synopsis of the Mollusca of the 

Cretaceous formation, p. 58, 1861. 

Meek, U.S. Geol. Survey Terr. Rept., vol. 9, p. 316, 

pl. 39, figs. 3 a-c, 1~76. 

Meek's description: 

Shell rather thick, obliquely compre~ed subglobose or 

subovate; spire short; volutions three and a half to four, 

last one comparatively large, sloping obliquely outward 

and downward almost immediately from the f)Uture above, 

and rounded below the middle; suture distinct but not 

deep; aperture large, subovate, being angular above, 

rounded below, forming a semiovate curve on the outer 

Side, and nearly straight on the inner; outer lip very 

oblique, being much produced forward above and extending obliquely backward, with a broad and slightly sinuous 

outline near the middle; inner lip nearly straight, moderately thick, and a little reflexed upon the body volution 

above the umbilical perforation; surface showing (on 

slightly weathered specimens) distinct, very oblique lines 

of growth. 

Length, 1.08 inches [27.43 millimeters]; breadth, 0.90 

inch [22.86 millimeters]; length of aperture, 0.85 inch 

[21.59 millimeters]; breadth of same, 0.57 inch [14.47 millimeters]. 

This shell will be at once distinguished from the foregoing [L. concinna and L. oceidentalis] by its greater 

thickness, shorter spire, obliquely compressed body 

volution, and the more oblique outline of its outer. lip. 

Its suture is also less deep than in either of the preceding 

species, owing to the fact that th~ volutions do not round 

into it but slope more immediately below it, nearly in the 

direction of the general slope of the spire. 

The specimen here figured, which is the 

largest one collected from · the Cannonball 

member, is 27 millimeters long and 25 millimeters broad, with an aperture measuring 22 

millimeters long and 14 millimeters wide. It 

agrees with the types in general form and all 

other features except that the umbilicus is 

slightly broader than in the types or any pre-
I 

FAUNA OF CANNONBALL MARINE MEMBER OF LANCE FORMATION. 37 

Lance specimen, although there is some variation in that respect, so that occasional specimens from the Claggett have the umbilicus 

almost as wide open as it is in the Lance 

specimens. 

Locality and position: The types were collected near Judith, Mont., in rocks long supposed to represent the Fox Hills sandstone but 

now known to be in the upper part of the 

Claggett formation. The species is also locally 

abundant in the same region in sandy beds at 

the base of the Bearpaw shale immediately 

overlying the Judith River formation. It has 

been reported from the Fox Hills sandstone 

of northern Colorado, and good examples of it 

have been obtained in the upper part of the 

typical Fox Hills in Tps. 20 and 21 N., R. 25 E., 

north of Grand River, N.Dak.. In the Cannonball marine member of the Lance formation it 

has been collected on Heart River threequarters of a mile' west of Mandan (figured 

specimen), 12 miles south of Almont, in sec. 9, 

T. 133 N., R. 85 W., and in T. 133 N., R. 88 W., 

all in North Dakota. 

Family TURRITELLIDAE. 

Genus TUB.RITELLA Lamarck. 

Turritella haresi Stanton, n. sp. 

Plate VI, figure 12. 

Turritella ap. Stanton, Geol. Soc. America Bull., vol. 25, 

p. 352, 1914. 

Shell small, slender, ·with obliquely flattened 

whorls; sculpture consisting of four rather 

prominent, minutely tuberculated spiral lines, 

the lowest of which borders the suture and on 

the upper whorls may be concealed, while the 

next one above it is the largest and forms a 

carina on the last whorl; space above the larger 

spiral divided by the other spirals into three 

equal parts, the upper of which is beveled to 

the suture. 

The type specimen, consisting of about nine 

whorls, is 10 millimeters in length and 3 

millimeters in greatest breadth. A crushed 

specimen supposed to belong to the species is 

over 20 millimeters long. 

In size, general form, and sculpture this 

little shell resembles the Fox Hills species 

Oerithiopsis moreauensis Meek and Hayden 

closely enough to suggest relationship, but the 

points of resemblance are only superficial. T. 

haresi has no anterior canal and apparently 

there are no plaits or ridges on the columella. 

The specific name is given for Mr. C. J. 

Hares. 

Locality and position: In a high bluff south 

of Cedar Creek, in the NW. i sec. 5, T. 129 N., 

R. 89 W., N.Dak., in the Cannonball marine 

member of the Lance formation. 

Fam.Uy APORRHAIDAE. 

Genus ANCHUB.A Conrad. 

Anchura (Drepanochilus) americana (Evans and Shumard). 

Plate VI, figure 13. 

Rostellaria americana Evans and ShumaJ,'d, St. Louis 

Acad. Sci. Trans., vol. 1, p. 42, 1857. 

Aporrhais americana Meek and Hayden, Acad. Nat. Sci. 

Philadelphia Proc., vol. 12, p. 423, 1860. 

Anchura (Drepanochilus) a-mericana Meek, Smithsonian 

check list of North American Cretaceous fossils, 

p. 19, 1864; U. S. Geol. Survey Terr. Rept., vol. 

9, p. 325, pl. 32, .figs. 8 a, b, 1876. 

This species was included in my preliminary 

list of the Cannonball fauna 1 as represented 

by both the typical form and a robust variety. 

As a result of further study and comparison 

these two forms are now described respectively 

as a new variety of Anchura americana and as 

a distinct new species, though it is believed 

that certainly the variety and possibly the 

species were directly derived from A. americana. 

The original types of the species came from 

Grand and Moreau rivers, S.l)ak., presumably 

from the Fox Hills sandstone. The specimens 

figured and more fully described by Meek also 

came from the Fox Hills sandstone on Moreau 

River, and it is noteworthy that these specimell:s served as the types of the subgenus 

Drepanochilus, which. does not seem to differ 

from the subsequently described DVmorphosoma 

of Gardner. The species is common in the 

Fox Hills sandstone, in the upper part of 

the Pierre shale, and in the Bearpaw shale. 

The figure here given for comparison with 

the new variety pusilla is a photograph of a 

somewhat immature specimen taken from the 

same lot which furnished the shells figured by 

Meek. 

1 <reol. Soc. America Bull., vol. 25, p. 352, 1914. 
38 SHORTER CONTRIBUTIONS TO GENERAL GEOLOGY, 1920. 

Anchura (Drepanochilus) americana var. pusilla Stanton, miles south of Leith, 12 miles south and 19 

n. var. miles southwest of Almont, and 6 miles northPlate VI, figures 14 and 15. west of Solen, N. Dak., all in 'the Cannonball 

marine member of the Lance formation. Anchura americana (Evans and Shumard) Stanton, Geol. 

Soc. America Bull., vol. 25, p. 352, 1914. 

Shell small, fusiform, consisting of about 

seven volutions; spire about equal to length of 

aperture and canal, with rounded volutions; 

last whorl with a strong carina above the 

middle and two successively smaller carinae 

below, the lower of which is sometimes obsolescent; anterior canal short and straight; expanded outer lip with a pointed, slightly 

upturned process that bears the continuation 

of the main upper carina to its end, above 

which the margin is concave, while below it 

forms a very gentle sigmoid curve or is almost 

straight to the end of the canal; no posterior 

canal, though the winglike outer lip extends 

upward and is applied to part of the penultimate whorl; inner lip moderately thick and 

connected above with the outer lip; surface 

marked by numerous small curved ribs crossed 

by fine, threadlike spiral lines, there being 25 

or more of the ribs and from 13 to 17 of the 

lines visible on each of the larger whorls of the 

spire. On the last whorl the ribs are gradually 

reduced to tubercles on the principal carina 

and the spiral lines are increased by the intercalation of smaller ones until on the outer part 

of the wing there are about 10 above the upper 

carina, 6 between that and the middle carina, 

4 between the middle and lower carinae, and 

about 15 below the lower carina. 

Height, 11.5 millimeters; breadth of last 

whorl exclusive of wing, 5 millimeters; apical 

angle, about 30°. 

This little shell agrees with A. (D.) americana in almost every detail except size, and it 

is therefore regarded as only a dwarfed variety 

of that species, as the varietal name selected 

suggests. A comparison of the enlarged figures 

(14 and 15) of the variety with the natural-size 

figure (13) of a somewhat immature specimen 

of the typical form emphasizes the agreement. 

Locality and position: The figured types 

with numerous other specimens were collected 

near Gr!tnd River post office in sec. 12, T. 22 

N., R. 12 E., S. Dak. The species has also 

been collected 9 miles east, 8 miles southeast, 

and 7 miles southwest of Lemmon, S.Dak.; a 

quarter of a mile east of Bloom, S. Dak.; 7 

Anchura (Drepanochilus) perveta Stanton, n. sp. 

Plate VII, figures, la-3b. 

Anchura americana (Evans and Shumard), robust variety, 

Stanton, Geol. Soc. America Bull., vol. 25, p. 352, 

1914. 

Shell of medium size, fusiform, consisting of 

eight or more whorls; spire considerably shorter 

than combined length of aperture and canal, 

with strongly rounded whorls tending to become subcarinate; last whorl with three conspicuous carinae, of which the uppermost is 

largest and extends to the upturned pointed 

end of the winglike outer lip, and the lowest 

one is smallest; anterior canal short, narrow, 

and straight; lower and outer margin of the 

expanded outer lip forming a broad sigmoid 

curve, upper margin strongly concave, with 

varying curvature in different individuals, and 

extended upward on the spire to the antepenultimate whorl; no posterior canal; inner 

lip connected above with the outer lip and 

thickened by a heavy callus, which is especially 

prominent over the middle and lower carinae, 

beneath which it is suddenly contracted; outer 

lip also greatly thickened by an internal 

deposit on mature specimens; surface of the 

spire marked by strong oblique or slightly 

curved ribs crossed by fine, inconspicuous, 

closely arranged spiral lines, there being about 

15 or 16 ribs and 30 or more lines on each larger 

whorl of the spire. On the last two whorls the 

ribs are gradually shortened until on the back 

of the last whorl they are reduced to strong 

tubercles on the upper carina and cease entirely 

before the carina reaches the wing. 

Height of medium-sized specimen, 29 millimeters; breadth of last whorl exclusive of 

wing, 13 millimeters, with wing, 21 millimeters; 

apical angle, about 30°; greatest thickness of 

outer lip, 4.5 millimeters; callus on inner lip, 

3.5 millimeters. Slight variations in the proportions of the shell and in the form of the 

outer lip are shown by the other two figured 

specimens. 

This species is probably the most abundant 

gastropod in the Cannonball fauna. In the 

preliminary lists it was treated as a variety of 
FAUNA OF CANNONBALL MARINE MEMBER OF LANCE FORMATION • 89 

.A.nchura americana in which the whole shell 

had become more robust, with exaggerated 

sculpture and thickened callus deposits suggesting the old-age characteristics-of an overgrown· individual. The type of .A. americana 

var. pusilla if enlarged a little more than two 

diame~ers and with all the sculpture much 

emphasized would make a similar shell, but 

closer comparison shows that the two species 

are not so closely related and .A.. peTVeta can 

be easily distinguished by its larger and less 

numerous vertical ribs, more numerous and 

less conspicuous spiral lines, and much stronger 

carinae, as well as by its greater size. Even 

small young specimens showing only the spire 

are easily separated by the differences in 

sculpture. 

Locality and position: The type and figured 

specimens came from Cannonball River in T. 

133 N., R. 88 W., about 6 miles south of Kayser, 

N. Dak., where the species is abundant. It 

has been recognized in collections from about 

15 other localities distributed over most of the 

area of the Cannonball marine member of the 

Lance formation from a point 4 miles south 

of Morristown, S.Dak., to a point on Missouri 

River 1 mile south of Price and 19 miles north 

of Mandan, N. Dak. It is not known to range 

outside of the Cannonball member. 

Anchura (Drepanochilus) perveta var. gracilis 

Stanton, n. var. 

Plate VII, figures 4a and 4b. 

This variety differs from the type of the 

species in its more slender form, its straighter 

outer lip or wing, and its much longer anterior 

canal, though the last-named feature may be 

in part due to the accident of preservation. 

In some ·specimens of the typical form the 

canal or beak looks as if it may have been 

broken or worn off during life. In ,all other 

details the variety agrees with the type. 

Height of figured specimen, 39 millimeters; 

breadth of last whorl exclusive of wing, 11 

millimeters, with wing about 21 millimeters; 

apical angle, about 25 °. The anterior can,al 

below the expanded outer lip is 9 millimeters 

in length, which is about twice as long as in 

the typical form. 

Locality and position: The figured specimens and several others were obtained on 

Cannonball River in the SW. i sec. 29, T. 133 

N., R. 88 W., about 6 miles south of Kayser, 

N.Dak., in the Cannonball marine member of 

the Lance formation. Several specimens were 

also collected from the same member on 

Cedar Creek in the NW. i sec. 9, T. 13 N., R. 

90 W., N. Dak. 

Family STROMBIDAE. 

Genus CALYPTRAPHORUS Conrad. 

Calyptraphorus septentrionalis Stanton, n. sp. 

Plate VII, figures 5a-5d and 6. 

Helicaulax? sp. Stanton, Geol. Soc. America Bull., vol. 

25, p. 352, 1914. 

Shell of medium size, consisting of about 10 

nearly flat whorls which in immature shells are 

covered by numerous fine, threadlike spiral 

lines and less conspicuous curved costae, which 

become obsolete on the later whorls. In the 

adult a heavy flat callus covers the entire front 

side of the spire, completely concealing the 

whorls, and a thinner deposit glazes the dorsal 

aspect, obscuring but not entirely concealing 

the sutures ang. the surface sculpture. 

The fragmentary type, consisting of · the 

larger part of the spire, ·is 33 millimeters in 

height and 16 millimeters in greatest breadth 

and has an apical· angle of about 25°. A 

smaller specimen which is believed to represent 

an immature stage of this species before the 

callus was developed is 12 millimeters in height 

and 8 millimeters in greatest breadth.· These 

two specimens from the same locality are the 

only known examples of the species. 

In the preliminary list of the Cannonball 

fauna this form was doubtfully referred to 

H elicaulax, but further comparison has shown 

so close a resemblance to Oalyptraphorus velatus 

Conrad in form, sculpture, and the nature of the 

callus which envelops the spire that there can 

be little doubt that the two species belong to 

the same genus, even though the form of the 

aperture is entirely unknown in 0. septentrionalis. Specifically 0. septentrional is may 

be distinguished even in such fragmentary 

specimens as are here figured, by its slightly 

flatter whorls and the much weaker sculpture, 

particularly the costae of the spire, when not 

concealed by the callus. If the entire shell were 

preserved doubtless other differences would be 

evident. 

The occurrence of the genus Oalyptraphorus 

in the Ca~onball fauna is interesting and im-
40 SHORTER CONTRIBUTIONS TO GENERAL GEOLOGY, 1920. 

portant from the fact that so far as the United 

States is concerned the genus has been considered characteristic of the Eocene. 0. velatus 

was described from specimens found in the 

Claiborne, but it occurs also in the Jackson and 

is represented by the variety compressa Aldrich 

in the Midway or lowest Eocene of the Gulf 

Coastal Plain. This variety is a stouter shell, 

though its sculpture does not differ greatly from 

that of 0. septentrional'is. The other American 

species, 0. trinodiferus Conrad and 0. jacksoni 

Clark, are found in Eocene formations later 

·than Midway. Rostellaria palliata Forbes, a 

Cretaceous species found in the Trichinopoly 

and Arrialoor groups of India, has been referred 

to Oalyptraphorus by Gabb,l and the figures 

published by Stoliczka 2 make this reference reasonable, although Stoliczka says 3 that it" does 

not seem to be fully justified for the present," 

and it is specifically, very different from all the 

American species. 

Locality and position: The type of O.septentrionalis was found in a hluff on Cannonball 

River in the SW. ! sec.- 17, T. 133 N., R. 88 W., 

about 5 miles southeast of Kayser, N. Dak., in 

gray shales of the Cannopball marine member 

of the Lance formation. 

Family BUCCINIDAE. 

Genus CANTHARUS Bolten. 

lens, forming, with the fine lines of growth, a faint textile 

marking, entirely subordinate to and distinct from the 

greatly coarser network formed by the crossing of the folds 

and revolving bands; aperture rather narrow oval; . outer 

lip faintly cross sulcated at the edge within and slightly 

s.inuous above; inner lip united to the outer bne above a.nd 

rather closely connected with the smooth, .tortuous, and 

arcuate columella. 

Length, 1.43inches [36.3 millimeters]; breadth, 0. 75 inch 

[19 millimeters]; apical angle convex, divergence about 

540. 

Four or- five of the revolving bands on the body whorl 

and two of those on each turn of the spire are larger than 

the others and form rather distinct nodes at the points 

where they cross the folds. Below these four larger bands 

on the body volution there are about five or more smaller 

ones, which diminish in size and become-more oblique on 

approaching the canal, while on the obliquely flattened 

upper part of the whorls there are (:lOme three or four much 

smaller and less prominent bands or lines. 

Locality and position: Meek and Hayden's 

single specimen was collected near the mouth 

of Heart River, N. Dak., in beds supposed to 

belong to the Fox Hills sandstone but now 

known to belong in the Cannonball marine 

member of the Lance formation. A .small 

specimen has been obtained in the same member in T. 33 N., R. 88 W., about 6 miles south 

of Kayser,.N. Dak., and a very small specimen, 

10 millimeters long, which is believed to be a 

you,ng individual of this species, was collected 

in the Fox Hills s~ndstone about 4 miles northwest of Wakpala, S.Dak. 

Cantharus (Cantharnlus) vaughani (Meek and Hayden). Genus PYRIFUSUS Conrad, 

Plate VII, figures 7a and 7b. Pyrifusus (Neptunella) newberryi (Meek and Hayden). 

Fusus vaughani Meek and Hayden, Acad. Nat. Sci. Philadelphia Proc., vol. 9, p. 138, 1857. 

Cantharus? vaughani Meek, Smithsonian check list of 

North American Cretaceous fossils, p. 22, 1864. 

Cantharus ( Cantharulus) vaughani Meek, U. S. Geol. Survey Terr. Rept., vol. 9, p. 377, pl. 32, !J.gs. 5 a, b, 

text fig. 48, 1876. 

Meek's description: 

Shell oval-fusiform, rather thick; spire turreted, moderately elevated, composed of six to six and a half convex 

whorls, which are obliquely a little flattened or very 

slightly concave above; last turn tapering quite abruptly 

into the rather narrow, moderately produced canal; suture 

distinct; surface of each volution ornamented by about 

fifteen small, equidistant, vertical folds, equaling the 

depressions between; crossing these are a series of small, 

rather elevated, regular, revolving bands, leBB than the 

intermediate spaces; over the entire surface very fine, 

obscure, revolving striae may also be seen by the aid of a 

1 Gabb, W. M., Am. J.our. Conchology, vot 4, p. 142, 1868. 

2 s~oliczka, F., Palaeontologia Indica, Cretaceous 'fauna of southern 

India, vol. 2, pl. 2, figs. 18-20, 1868. 

~ Idem, p. 24. 

Plate VII, :figures Sa. and 8b. · 

Fusus newberryi Meek and Hayden, Acad. Nat. Sci. 

Philadelphia Proc., vol. 8, p. 66, 1857. 

Fusu,s (Pyrijusus'f) newberryi Meek and Hayden, idem, 

vol. 12, p. 421, 1860. 

Pyrijusus newberryi Jr.[eek, Smithsonian check list of North 

Ameriq~.n Cretaceous fossils, p. 22, 1864; 

Pyrijusus (Neptunella) newberryi Meek, U: S. Geol. Survey Terr. Rept., vol. 9, p. 346, pl. 31, figs. 6 a.-f, 

text fig. 39, 1876. 

Meek's description: 

Shell rhombic-subfusiform, rather thick; spire conical, 

acute at the apex when not eroded; volutions five, 

obliquely flattened or a little concave above and convex: 

around the middle, where they are orna.men~ by a row 

of more or less prominent, vertically elongated nodes, or 

costae; last turn comparatively large and tapering rather 

abruptly into the rather short, straight caiull below; surface marked by distinct lines of growth, crossed by nu;. 

merous well-defined, round, threadlike, revolving linea; 

suture linear; aperture rhombic-obovate, rather obtusely 

angular above and narrowing more gradually below; outer 

.. 1 
FAUNA OF CANNONBALL MARINE MEMBER OF LANCE FORMATION. 41 

lip beveled; inner lip scarcely distinct from the slightly 

arcuate columella. 

Length, 1.43 inc~es (36.3 millimeters]; breadth, 0.81 

inch [20.57millimeters]; length of aperture and canal, 0.87 

inch (21.1 millimeters]; breadth of aperture, 0.32 inch 

(8.13 millimeters]; apical angle convex, regular, or even 

a little concave; divergence variable but usually about 

60° to 65°. 

This species varies more or lees in form, as well as in the 

prominence of the nodelike costae. In some individuals 

the spire is more elevated and the body whorl proportionally much narrower than in others. The nodes, or 

costae, of which about 15 may be counted on the last 

tum are usually quite distinct on all the whorls, but in 

som~ specimens they become obsolete on the last one. 

* * * On the upper sloping part of the whorls the revolving lines are in most cases smaller and about equal to 

the spaces between; farther down, however, they are generally a little larger, rather more distant, and often have 

between each two of the principal ones a S'maller line. 

Locality and position: This species was orig-

. inally described from specimens collected in 

the Fox Hills sandstone of Moreau River and 

the Fox Hills, S. Dak. All except one of the 

specimens later figured by Meek are labeled 

Moreau River, and the exception (6e of Meek's 

figures) is one of a lot labeled "Yellowstone, 

150 miles above mouth," which doubtless came 

from the upper part of the Pierre shale a few 

miles west of Glendive, Mont. In the Cannonball marine member of the Lance formation 

·the few imperfect and immature specimens referred to the species are very similar in form 

and sculpture to those from the Yellowstone. 

The best of these, which is figured, was collected by Mr. E. T. Hancock on Heart River in 

.yellowish-brown sandstone 110 feet above water 

in the SW. ! NW. ! sec. ,6, T. 137 N., R .. 83 E., 

about 15 miles southwest of Mandan, N.Dak. 

Although much smaller than the type, it agrees 

well in form and sculpture and is believed to 

be a young shell. 

Pyrifusus (Neptunella) gracilis Stanton, n. sp. 

Plate VIII, figures la and lb. 

Shell small, fusiform, consisting of about 

five whorls which are closely appressed, slightly 

flattened above, and convex around the middle; 

last whorl tapering gradually into the moderat~ly long canal. Surface ornamented by 

about 13 short vertical ribs on the middle 

convex part of each whorl and by numerous 

fine, threadlike spiral lines; outer lip simple, 

inner lip inconspicuous; aperture .lance-ovate. 

Height, 26 millimeters; greatest breadth, 12 

millimeters; height of aperture and canal, 17 

millimeters; breadth of aperture, 5 millimeters; 

apical angle, about 50°. 

This species has about the proportions of 

Pyrifusus ( Neptunella) intertextus Meek and 

Hayden, but it is a smaller shell and differs in 

details of sculpture. 

Locality and position: The type was collected near the top of a bluff .on the north side 

of Heart River three-quarters of a mile east of 

Mandan, N. Dak., in the upper part of the 

Cannonball marine member of the Lance formation. Two fragmentary specimens, one of 

which represents a shell about 38 millimeters 

high, were obtained at about the same horizon 

in sec. 11, T. 132 N., R. 88 W., about 7 miles 

south of Leith, N.Dak. 

Genus LEVIFUSUS Conrad. 

Levifusus? tormentarius Stanton, n. sp. 

Plate VIII, figures 2a, 2b, and 3. 

Turris sp. related to T. contortus Meek and Hayden, 

Stanton, Geol. Soc. America Bull., vol. 25, p. 352, 

1914. 

Shell small, rhombic-subfusiform, consisting 

of about six rapidly increasing whorls; last 

whorl forming nearly two-thirds the length of 

the shell, bluntly bicarinate around the middle, 

gradually narrowing into the short canal; upper 

carina, which is also visible on the whorls of the 

spire just above the suture, with about 20 

small nodes to each whorl; lower carina also 

minutely nodose; upper slope of the whorl 

concave; outer lip apparently smooth within, 

broadly sinuous between the suture and the 

upper carina, as shown by the fine lines of 

growth; columella slightly twisted below; 

surface covered by numerous fine, threadlike 

spiral lines which show a tendency to alternation in size. 

Height, 28 millimeters; breadth, 11 millimeters; height of aperture, 12 millimeters; 

breadth of aperture, 5 millimeters. . 

This species is ·apparently congeneric with 

Levifusus trabeatus Conrad and L. pagoda ( Heilprin), both of which are found in the Midway 

and Wilcox groups of the Gulf Coastal Plain 

Eocene. In form and sculpture it especially 

resembles the variety of L'. trabeatus figured by 

Aldrich 1 and by Harris 2 from the Midway of 

1 Aldrich, T. H., Bull. Am. Paleontology, vol.l, No.2, pl. 4, fig. 6,1S95. 

2 Harris, G. D., idem, vol. 1, No. 4, pl. 9, fig. 10, 1896. 
42 SHORTER CONTRIBUTIONS TO GENERAL GEOLOGY, 1920. 

Alabama, but it differs in having more numerous and smaller nodes on the carina and in 

lacking internallirae on the outer lip. 

Locality and position: The type was found 

Family FUSIDAE. 

Genus FASCIOLARIA Lamarck. 

Fasciolaria lloydi Stanton, n. sp. 

in the Cannonball marine member of the Lance Plate VIII, figures na and llb. 

formation in the SW. l sec. 29, T. 133 N., R. . . . ' 

88 W., on Cannonball River about 6 miles Fasc-iolaria bu.ccin:oides Meek and Hayden, Stanton, Geol. 

h f K N D k An th . . Soc. Amenca Bull., vol. 25, p. 352, 1914. 

sout o ayser, . a . o er specnnen, 

which is also figured, was found in the same 

member in the SW. l sec. 34, T. 23 N., R. 17 

E., 9 miles east of Lemmon, S.Dak. 

Genus PYROPSIS Conrad. 

Pyropsis hancocki Stanton, n. sp. 

Plate VIII, figure 4. 

Shell small, pyriform, consisting of about 

four rapidly increasing convex whorls; spire 

low, conical; sutures distinctly impressed; 

whorls flattened above, the last one faintly 

tricarinate around the middle and abruptly 

contracted into the long, slender, slightly 

curved anterior canal; surface bearing in addition to the carinae slender, somewhat distant 

vertical ribs (about 15 to the whorl), which 

tend to be nodose at the intersections with the 

carinae, and many fine, threadlike spiral lines, 

of which there are four on the upper surface of 

the last whorl, three between the upper and 

middle carinae, and more than a dozen below 

the lower carina. 

Height, 15 millimeters; greatest breadth, 8 

millimeters. 

This species, which is represented by a single 

specimen collected by Mr. E. T. Hancock, of 

the United States Geological Survey, has 

almost the form and proportions of Pyropsis 

whitfieldi Weller 1 from the Navesink marl, 

but it is slightly more slender as well as smaller 

and has relatively finer sculpture. 

Locality and position: On Heart River in 

theSE. ! sec. 10, T. 138 N., R. 88 W., about 12 

miles southwest of Mandan, N. Dak., in a 

brown sandstone about 75 feet below the top of 

the Cannonball marine member of the Lance 

formation. 

Shell small, short fusiform, consisting of 

about five convex whorls; last whorl gibbous, 

forming about two-thirds the length of the 

shell. and contracting rather abruptly into the 

short, slightly curved canal; suture slightly 

channeled; surface marked by vertical ribs, of 

which there are 14 on the last whorl, crossed 

by relatively strong spiral lines, which are 

slightly narrower than the interspaces and 

tend to be tuberculated at the intersections 

with the ribs; 12 spiral lines on the last whorl 

and only 4 visible on the spire; aperture narrow 

oval, tapering below; outer lip thin, not crenulate within; columella slightly twisted and 

bearing two distinct oblique plaits. 

Height, 1!1 millimeters; greatest breadth, 9 

millimeters; apical angle, about 60°. A larger 

specimen is 22 millimeters in height and 13 

millimeters in breadth. 

This species is dosely related to F. buccinoides Meek and Hayden, especially the 

costate variety/ with which it agrees in general form and in the character of the two plaits 

on the columella. Its sculptme also is similar 

but is relatively coarser. The vertical ribs are 

longer and better developed, and the spiral. 

lines are coarser and more widely spaced, so 

that only four of them are visible on the next 

to the last whorl, as compared with seven in 

F. buccinoides. On account of these differences 

in the sculpture and the smaller size it has been 

deemed necessary to recognize this form as a 

distinct species. 

Locality and position: The type was found 

in sec. 31, T. 133 N., R. 8 W., about 6 miles 

south of Kayser, N.Dak. The larger specimen 

above mentioned was collected in sec. 5, T. 22 

N., R. 20 E., about 4! miles southeast of 

1 Weller, Stuart, New Jersey Geol. Survey, Paleontology, voi. 4, 1 Meek, F. B., U. S. Gi.Ol. Survey Terr. Rept., vol. '9, p. 358, pl. 31, 

p. 750, pl. 88, figs. 14-16, 1907. fig. sc, 1876. 
FAUNA OF CANNONBALL MARINE MEMBER OF LANOE :FORMATION. 48 

Morristown, S. Dak. Another specii;nen was 

obtained in the NW. l sec. 11, T. 132 N., R. 88 

W., about 7 miles south of Leith, N. Dak., and 

a fragmentary specimen in the SW. l sec. 15, 

T. 134 N., R. 86 W., about 4 miles southwest 

of Lark, N. Dak., all from the Cannonball 

marine member of the Lance formation. 

Fasclolaria? mandanensis Stanton, n. sp. 

Plate VIII, figures 5-7. 

Shell rather small, short fusiform, consisting 

of about six moderately convex whorls, which 

are somewhat flattened on the upper third 

especially of the last whorl, which forms about 

two-thirds of the total length of the shell; 

canal short and slightly curved; suture distinct; surface marked by prominent vertical 

ribs, of which there are 16 on the last whorl, 

crossed by strong spiral lines, which are about 

equal to the interspaces and of which 6 are 

visible on the spire and about 20 on the last 

whorl; aperture narrow oval, tapering below; 

outer lip thin, rather coarsely crenulate 

within; columella. with two oblique plaits, of 

which the upper one is the stronger. 

Height of most nearly complete specimen, 

about 30 millimeters; greatest breadth, 15 

millimeters; apical angle, about 60°. The 

other specimen indicates a height of about 35 

millimeters and breadth of 17 millimeters. 

This species appears to be related to both 

F. buccinoides and F. lloydi, but it differs from 

both sufficiently in details of form and sculpture to justify its recognition as . a distinct 

species. 

Locality and position: Represented by only 

the two figured specimens, which were collected 

near the top of the bluff on the north bank of 

Heart River about a mile west of Mandan, 

N. Dak., in the u~per part of the Cannonball 

marine member of the Lance formation, and a 

fragment from the NW. l sec. t1, T. 132 N., 

R. 88 W., about 7 miles south of Leith, N. Dak. 

Fasclolaria? eordensis Stanton, n. sp. 

Plate VIII, figures Sa-10. 

Shell very small, consisting of about five 

moderately convex whorls, which tend to be 

slightly shouldered at the top; last whorl with 

short anterior canarl forming nearly two-thirds 

of the length of the shell; surface marked by 

numerous fine, closely arranged spiral lines, 

which are slightly broader than the intervening 

grooves, and by sn1all, narrow vertical ribs 

which on the type specimen are fairly well 

developed on the next to the last whorl but 

become obs-olete on the last whorl; 14 spiral 

lines on the last whorl and 7 visible on the spire; 

outer lip thin, smooth within; columella with 

two distinct oblique plaits , below which there is 

an incipient fold or denticle that does not continue back inside the shell. 

Height, 6 millimeters; greatest breadth, 4 

millimeters; apical angle, about 50°. 

The type is a very small shell, believed to be 

an immature individual, which is congeneric 

with F. buccinoides and F. lloydi but differs 

from both in details of sculpture. Two other 

specimens from the type locality, one of which 

is figured, have the vertical ribs better preserved. ' 

Locality and position: In the Cannonball 

marine member of the Lance formation in the 

SW. l sec. 24, T. 13() N., R. 88 W., on Heart 

River about 19 miles southwest of Almont, 

N.Dak. Another specimen (fig.10), which was 

collected on Heart R:iver in the SW. l sec. 20, 

T. 136 N., R. 86 W.:· about 12 miles south of 

Almont, differs from the type- in its more distinctly shouldered whorls and its lack of vertical ribs and may belong to another species. 

Fasciolaria? (Mesorhyti:s) dakotensis Stanton, n. sp. 

Plate VIII, figures 13a-14b. 

Fasciolaria (Piestockilus) (:ulbertsoni Meek and Hayden. 

Stanton, Geol. Soc. America Bull., vol. 25, p. 352, 

1914. 

Shell elongate fusiform, consisting of about 

nine moderately convex whorls; spire produced, 

about equal in length 1~0 the aperture and canal; 

whorls each with about 15 rather prominent, 

nearly straight, vertical ribs, which are narrower than the interspaces and on the last whorl 

do not extend below the middle· and tend to 

become obsolete tow:a,rd the outer lip; canal 

nearly straight, moderately produced; columella almost straight, bearing opposite the 

·middle of the apertur~~ three distinct, not very 

oblique folds or plaits, of which the uppermost 

is smallest and is separated from the middle 

one by a slightly narrower interval than that 

between the middle n.nd the lowest; aperture 

lance-oval; surface m:u-ked by very fine lines 

of growth parallel to the ribs and by fine, some-
44 SHORTER CONTRIBUTIONS TO GENERAL GEOLOGY, 1920. 

what irregular spiral lines which are considerably broader than the very fine impressed lines 

separating them. 

Height of type, 38 millimeters; greatest 

breadth, 12 millimeters; apical angle, about 30°. 

The smaller figured specimen is 15 millimeters 

in height and 5.3 millimeters in · greatest 

breadth. 

This species is closely related to Fasciolaria? 

. ( Jfesorhytis) gracilenta Meek, which was described 1 as the type of the subgenus Mesorhytis 

and was collected from the upper part of. the 

Pierre shale on "Yellowstone River 150 miles 

above mouth," probably near Glendive, Mont. 

Apparently Meek failed to label the type of 

Fasciolaria ( Mesorhytis) gracilenta, and some 

years later it was identified as F. (Piestochilus) 

culbertsoni. With this false label it has remained in the collections of the United States 

National Museum until January, 1918, when it 

was recognized as the original of Meek's figure 

and description during the critic'al study of 

the Cannonball specimens that had been identified as Fasciolaria. (Piestochilus) culbertsoni, 

partly on account of the confusion occasioned 

by the wrong labeling of F. ( Mesorhytis) gracilenta.. Meek described Jlesorhytis as nearly 

agreeing with Piestochilus .in form but distinguished from it by stronger and less oblique 

columellar plaits, which are exposed directly 

opposite the middle of the aperture. In 3/. 

gracilenta as in M. dakotensis there are three 

strong columellar plaits. The typical costate 

form of Piestochilus culbertsoni has four moderately developed plaits on the columella (seen 

in two specimens of the type lot), but the larger 

form, with vertical costae almost lf:l.cking, has 

only one well-developed columellar plait, with 

an obscure one above it as observed in several 

broken specimens that show this feature. If 

this difference should prove to be constant the 

two forms should not be referred to the same 

species, and Evans and Shumard's name 

haydeni should then be revived for the larger, 

noncostate form. 

Fasciolaria ( Mesorhytis) dakotensis may be 

distinguished from F. (JI.) gracilenta by its 

much finer and less conspicuous spiral sculpture 

and its less numerous and somewhat stronger 

vertical ribs. 

Some of the Eocene species that have been 

described as Jlitra appear to be closely related 

1 U. S. Geol. Survey Terr. Rept., vol. 9, p. 864, text fig. 45, 1876. 

to Mesorhytis. Good examples of these are 

Jfitra pomonkensis and M. potomacensis, described by Clark and lfartin 1 from the Eocene 

of Maryland. Meek probably had such forms 

in mind when he said that" Mesorhytis occurs 

in the Cretaceous and, apparently, also in the 

Tertiary." He further stated concerning the 

type of Mesorhytis: 

J am not at all mtisfied with the reference of this shell 

to the genus Fasciolaria, owing to the fact that the plaits 

of its columella are stronger and much less oblique and 

occupy so much higher a position than in Faswlaria 

proper. I do not beUeve, however, that such shells can 

be properly referred to any section of Mitra or Turricula, 

as is sometimes done. 

Locality and position: The type specimen of 

Fasciolaria (Mesorhytis) dakotensiswascollected 

in T. 133 N., R. 88 W., about 6 miles south 

of Kayser, N.Dak., and the other figured specimen was obtained in the SW. l sec. 17 of the 

same township. The species is also represented in collections from the west bank of 

Missouri River 1 mile south of Price, N.Dak.; 

Heart River in sec. 6, T. 137 N., R. 83 W., sec. 

16, T. 136 N., R. 84 W., and sec. 29, T. 136 N., 

R. 86 W.; sec. 28, T. 133 N., R. 88 W.; river 

bluff near Janes burg, N. Dak.; sec. 15,- T. 134 

N., R. 86 W.; sec. 9, T. 130 N., R. 90 W., 10 

miles southwest of Pretty Rock, N~ Dak.; and 

sec. 7, T. 22 N., R. 17 E., 8 miles southeast of 

Lemmon, S. Dak.-all in the Cannonball marine member of the Lance formation. 

Family VASIDAE. 

Genus PSri.OCOCHLIS Dall. 

Psilocochlis? occidentalis Stanton, n. sp. 

Plate VIII, figures 15a and 15b. 

Shell small, pyriform, consisting of about 

four whorls, the last one comparatively large, 

very convex on the periphery, flattened and 

abruptly contracted below into the short, 

slightly curved canal; columella with three 

very strong folds, of which the uppermost is 

the strongest; surface with inconspicuous 

growth lines and numerous fine,. closely ar-

·ranged spiral lines that are just visible to the 

unaided eye. . 

Height, 12 millimeters; greatest breadth, 11 

millimeters; height of aperture, 9 millimeters. 

This little shell, which is represented by the 

single type specimen, is unlike anything hitherto 

1 Clark,· w. B., and Martin, G. C., Maryland Geol. Survey, Eorene, 

pp. 132, 133, pl. 21, figs. 10, 11, 1901. 
FAUNA OF CANNONBALL MARINE MEMBER OF LANOE FORMATION. 45 

reported from the faunas of the Rocky Mountains or Great Plains. On the suggestion of W. 

H. Dall it is referred with some doubt to his 

genus Psilocochlis, which it resembles in form 

and especially in the character of the columellar 

plaits. The type and only described species of 

that genus is Psilocochlis mccalliei, which was 

found in rocks of Claiborne age near Hephzibah, 

Ga. . It is much larger than the shell here described and differs in two other important characters in having a distinct umbilicus and a 

coating of enamel that covers the spire and 

conceals the sutures. It is possible, of course, 

that Psilocochlis 1 occidentalis is an immature 

shell which would develop the enamel coating 

in the adult st&ge, but probably well-preserved 

adult specimens of both species would show 

. that though somewhat related they really belong to distinct genera. 

Locality and positi9n: North of Cedar River 

about 10 miles southwest of Pretty Rock, N. 

Dak.,in the NW.i sec. 9, T. 130 N., R. 90 W., 

in the Cannonball marine member of the Lance 

formation. 

Family TURBl'l'IDAE. 

Genus T"'l.UUS Bolten. 

Turris lloydi Stanton, n. sp. 

Plate VIII, figure 16. 

Turris minor (Evans and Shumard)? Stanton, Geol. 

Soc. America Bull., vot 25, p. 352, 1914. 

Shell small, slender, fusiform, consisting of 

about ten subangular whorls, with the spire 

considerably longer than the apertl!re and canal; 

sinus of outer lip comparatively deep and broad, 

situated on the most convex part of the shell, 

which also bears about 17 short curved ribs or 

nodes on each whorl; upper part of whorl somewhat constricted, suture minutely channeled; 

surface marked by relatively strong spiral lines,. 

of which about 12 are visible on the spire, and 

by sinuous lines of growth, which are strongest 

on the upper slope of the whorl just below the 

suture. 

Height, with most of the canal missing, 11 

millimeters; breadth, 4.5 millimeters. 

This species resembles Pleurotoma nebulosa 

Harris,t from the Wilcox group, but it differs 

in its more numerous ribs and other details of 

sculpture. 

1 Bull. Am. Paleontology, vol. 3, p. 13, pl. 2. fig. 1, 1899. 

·13595°-21----4 

Locality and position: The type was collected on Cannonball River in the SW.isec.ll, 

T. 132 N., R. 88 W., about 7 miles south of 

Leith, N. Dak., in the Cannonball marine member of the Lance formation. A smaller specimen was obtained at about the same horizon on 

Heart River 1 mile west of Mandan, N. Da.k. 

Turris eordensis Stanton, n. sp. 

Plate VIII, figure 12. 

Shell small, fusiform, consisting of seven or 

eight subcarinate whorls, with carina on spire 

slightly below the middle of visible part of 

whorl; spire about equal to aperture and canal 

in height; sinus of outer lip narrow and slitlike, situated on the carina; surface marked by 

many fine spiral lines, which on the last whorl 

below the carina tend to alternate in size. 

Height, 14 millimeters; breadth, 7 millimeters. 

Locality and position: The single type specimen was collected on Heart River in the 

SW. l sec. 24, T. 136 N., R. 88 W., about 19 

miles southwest of Almont, N. Dak., in the 

Cannonball marine member of the Lance 

formation.' 

Turris? tormentaria Stanton, n. sp. 

Plate IX, figures 1a and lb. 

Shell of medium size, slender fusiform, consisting of about 10 strongly carinated whorls 

with the high, narrow carina just above the 

suture; spire about equal in height to aperture 

and canal; growth lines not well enough preserved to show form of sinus; surface ·marked 

by fine closely arranged spiral lines which tend 

to become obsolete. 

Height, 35 millimeters; breadth, about 11 

millimeters. 

Locality and position: The single type specimen was collected on Cannonball River in T. 

133 N., R. 88 W., about 6 .miles south of 

Kayser, N. Dak., in the Cannonball marine 

member of the Lance forn1ation. 

Genus TURRICULA Schum.'acher. 

Turricula janesburgensis Stanton, n. sp. 

Plate IX, figures 2a and 2b. 

Shell of medium size, moderately stout 

fusiform, consisting of seven or more carinated 

whorls; spire not quite as long as the aperture 
46 SHORTER OO~TRIBUTIONS TO GENERAL GEOLOGY, i920. 

and canal; carina with about 14 obliquely 

elongated nodes or tubercles on each whorl 

and situated a little above the closely appressed 

suture on the spire; upper slope of the whorl 

above the carina concave and marked by the 

curved growth lines, which indicate the form 

of the broad, moderately deep sinus of the 

outer lip; surface also covered with fine, somewhftt irregular spiral lines, which tend to alternate in size. 

Height, 30 millimeters; breadth, 12 millime,. 

ters; height of aperture, 17 millimeters; 

breadth of aperture, about 5 millimeters. 

In general aspect thi~ species resembles 

Surcula na8'Uta (Whitfield), from the Wilcox 

group of Alabama, but it is a stouter shell and 

differs, in the details of sculpture. 

According to W. H. Dall 1 Turri.mtla is the 

valid name for the generic group usually 

called Surcula,.to which this shell apparently 

belongs. 

Locality and position: The type was collected with a smaller specimen from gravel in 

a bluff on Cannonball River near J anesburg, 

N. Dak., where it was evidently redeposited 

from a neighboring .exposure of the Cannonball 

marine member of the Lance formation. 

Turricula textills Stanton, n. sp. 

Plate IX, figures 3a and 3b. 

. Shell resembling Turricula janesburgensis in 

general form and coarser sculpture, but it has a 

relatively shorter canal, the upper slope of its 

Turricula bacata Stanton, n. sp. 

Plate IX, figures 4 and 5. 

Shen of medium _size, rather stout fUBiform, 

consisting of about six: or seven whorls; last 

whorl with a prominent suban.gular ridge above 

the middle bearing about 14 short ribs or nodes, 

which on the whorls of the spire become a row 

of beadlike nodes situated just above th~ appressed suture; slope above the row of nodes 

slightly concave and bearing the sharply 

curved growth lines that indicate the form and 

position of the broad and moderately deep sinus 

of the outer lip; surface also marked by fine 

spiral lines, not well preserved on the type, 

whiQh are mostly much narrower than the 

in terspaces. . 

Height of type, which lacks both apex ·and. 

the larger part of the canal, 27 millimeters; 

breadth_, about 24 millimeters. 

This species is related to Turricula janesburgensis, which differs in its more slender form, 

more distinctly carinate whorls, and more 

spinous nodes situated farther from the suture. 

Locality and position: The type was collected on Cannonball River in sec. 31, T. 133 

N., R. 88 W., about 6 miles south of Kayser, 

N. Dak. Another fragmentary specimen, which 

is also figured, was obtained ou lieart River 

in sec. 20, T. 136 N., R. 86 W., about 12 miles 

south of .Almont, N.Dak., both in the Cannonball marine member of the Lance formation. 

Turricula cincta Stanton, n. sp. 

whorls is more deeply concave, the carina is Plate IX, figures 6a and 6b. 

nearer to the suture, and the spiral sculpture is Shell smali, fusiform, consistmg' ()'of about six 

much finer, with more nearly equal and more 

closely crowded irregular lines. These dif- whortls, withd spireal abohut lsequ~ 1. in length tlo 

f b li d · if ifi aper ure an can ; w or Wit11 a varrow y , erences are e eve to JUSt y spec · c separa- ded · b h hi h · · d · h h · · 'bl th f roun carma, eneat w c 1s an rmpresse twn, t oug It IS possi e at uture collec- b d ul hi h · · h · h h · d' · · an or s cus, w c IS conspicuous on t e tiOns may s ow enoug mterme mte forms to 1 t h 1 b t th · h · 1 

th h diff. . · as w or u on e spire as Its ower marprove at t e erences are only of varietal . al d b th di h 1 · 

1 Onl · f h . gm conce e y e succee ng w or ; carma 

va ue. y one specunen o eac species has ul t th lin t 1 d th 

b 

cren a e; grow es s rong y curve on e 

een seen. 1 h uld f h h 1 h · Height, 24 millimeters; breadth, 10 millime- uppers ope or s ? er o t e w or' s oWing 

t h · ht f t 14 5 milli' · the form of the smus; surface also marked by 

ers; eig o aper ure, . meters; 1 t' el 1 1 d · alli 

b dth f t 4 millim. t re a IV y coarse, c ose y arrange sp1r nes, 

rea o aper ure, e ers. hi h d b b 1 h 

L lit d •t• 0 C b 11 R' w c ten to ecome o .so ete on t e upper . oca y an posi ton: n annon a IVer slope. 

~ T. 133 :·,DRk88 .w., :bo~t 6 miblesllsouth_ of Height of imperfect type, 11 millimeters;. 

ayser, ... · a ., In t e ~nnon a D1arme breadth, 5 millimeters; height of aperture, about 

member of the Lance formation. 7 millimeters; breadth of aperture, 2 mi.lli1 U.S. Nat. Mus. Proc., vol. 54, pp. 315,332,1918. meters. 

.. 
FAUNA OF CANNONBALL MARINE MEMBER OF LANOE FORMATION. 47 

The most distinctive feature of this species one-fourth longer ·than the. measured type. 

is the sulcus or furrow just beneath the carin·a Turris (SurC'I.ila) o8trarupis Harris,1 from the 

, on the last whorl. It is represented in the col- Midway formation, seems to be a related 

lections by only two specimens. species. 

Locality and position: The type was co}- Locality and position: The types of the 

lected in the Cannonball marine member of the species were collected in the Fox BinS sandLance formation on Heart River in sec. 29, stone on Moreau River, S. Dak! The speciT. 136 N., R. 86 W., about 12 miles south of mens now :figured were collected in theCannonAlmont,. N. Dak. The other specimen was ball marine member of the Lance formation on 

found at about the same horizon on Cannonball Heart River 10 miles north of Flasher, N. Dak., 

River in sec. 31, T. 133 N., R. 88 W.,. about 6 in the SW. 1 sec. 16, T. 136 N., R. 84 W. 

miles south of Kayser, N. Dak. 1 Other specimens were obtained on Heart River 

Tarrlcula? eontor:ta (Meek and Hayden). 

Plate IX, figures 7 and 8. 

F'uBul contortm Meek and Hayden, Acad. Nat. S.ci. Philadelphia Proc., vol. 8, p. 65, 1856. 

Pleurotomaria contorta Meek and Hayden, idem, vol. 12, 

p. 185, 1860. 

Turri8 contortm Meek and Hayden, idem, p. 422. 

Meek, Smithsonian check list of North American Cretaceous fOssils, p. 22, 1864. 

in the NW. i sec. 6, T. 137 N., R. 83 W.; in 

sec. 20, T. 136 N., R. 86 W., about 12 miles 

south of Almont, ·N. Dak.; and in T. 133 N., 

R. 88 W., about 6 miles south of Kayser, 

N.Dak., all in the Cannonball marine member. 

Family lUNGICULIDAB. 

Genus BINGICULA. Deshqea. 

Ringieula. dubbi Stanton. :a. sp. 

71uni8 (Surcula1) contortm Meek, U. S. Geol. Survey Plate IX, fi.gurea 9a, 9b. 

Terr. Rept., vol. 9, p. 885, pl. 31, figs. 7 a-c, text . . • 1ig. 49, 1876. · Cinuluz sp. Stanton, Geol. Soc. Amenca Bull., vol. 25, 

M k' d . . p. 352, 1914. 

ee s escnptlo:a.: Sh 11 ll l b · · f hr · e sma , g o ose, consiStmg o t ee or 

Shell. rather abort fusiform; spire turreted, moderately f 'dl · · elevated but not quite equaling the length of the aperture our rap I y 1ncreasmg convex volutions; spire 

and canal; volutions five and a half to six, distinctly con- short; sutures distinct, slightly channeled; apcave above, and convex around the middle, where they erture auriform, naiTOW above and broadly 

are each ornamented by about eleven oblique, flexuous, rounded below, without any anterior canal or 

elongated nod'ea, or costae, equaling the sinuosities be- emargination; outer lip greatly thickened, beartween; lut turn prominent around the· middle and taper- • · · urf · · ing obliquely into the rather abort, nearly straight canal Ing on Its Inner s ace a smgle relatively prombelow; suture distinct; aperture narrow subovate, angular inent denticle which is located below the middle 

above, moat convex on the outer aide, and tapering into of the aperture and opposite the space between 

the canal below; outer lip broadly prominent in outline the columellar plaits; inner lip thickened 

along the middle, somewhat contracted below, and again throughout and rather broad and flat below; 

curving backward into the broadly rounded, rather deep 1 11 · h 

sinus between the angle of the volutions and the suture co ume a Wit two strong transverse plaits; 

above; surface marked by fine but distinctlines of growth, surface smooth. 

which are crossed by numerous rather small, threadlike, Height and breadth, each 3 millimeters; 

revolving linea. height of aperture, 2 millimeters. 

Length, 1.09 inches [27.68 millimeters]; breadth, 0.55 This little shell has the globose form of a 

inch [13.97 millimeters]; length of aperture and canal, 0.7 o· A.l.' d l"k h 

inch [17.78 millimeters]; breadth of aperture,o.24 inch ~n·UNm an 1 e t at ·genus lacks an anterior 

[6.1 millimeters]; slope of spire nearly straight, with diver~ canal or notch, but its two strong eol1ll1lellar 

gence of about 42° in adult examples. folds, denticulate outer lip, and smooth surThis species as represented in the six speci- face seem to ally it more closely to Ringicula, 

mens of the type lot shows some variation in to which it is now tentatively referred. Posthe strength of the sculpture, especially of the sibly it should be made the type of a new 

vertical ribs. Those with more subdued sclllp- genus or subgenus, because it l~ks ·the anteture, such as the one depicted by Meek's text rior notch or canal that seems to be present in 

figure 49, are very similar to the specimens all described species of Ringicula and is usually 

from the Cannonball fauna, some of which as considered an important feature. 

indicated by imperfect specimens are about 1 Bull. Am. Pnleontology, vol.l, p.192, p1.17, flg.ta, 1896. 
48 SHORTER CONTRIBUTIONS TO GENERAL GEOLOGY, 1920. 

Locality and position: The type was collected in the Cannonball marine member of the 

Lance formation near Heart River in the SW. 1 

sec. 24, T. 136 N., R. 88 W., about 19 miles 

southwest of Almont, N. Dak. Other specimens were obtained in the same member on 

Heart River. about 1 mile west of Mandan, 

N. Dak., and in the SE. i sec. 10, T. 138 N., 

R. 83 W., about 12 miles southwest of Mandan; in theSE. i sec 8, T. 136 N., R. 83 W., 5 

miles east of Flasher, N. Dak.; and in the SE. 1 

sec. 21, T. 136 N., R. 82 W., 5 miles east of 

Strain, N. Dak. 

Family SCAPBANDBIDAE. 

Genus CYLICJINA LovEn. 

CyDehna scltula Meek and Hayden? 

Plate IX, figure 10. 

Oylichna scitula Meek and Hayden, Acad. Nat. Sci. Philadelphia Proc., vol. 12, p. 178, 1860. Meek, U. S. 

Geol. Survey Terr. Rept., vol. 9, p. 276, pl. 31, figs. 

3 a, b, 1876. 

Meek's description: 

Shell small, rather solid, narrow subelliptica.l, approaching subcylindrica.l; summit truncated and occupied by a 

comparatively large umbilicoid depression; aperture very 

narrow, arcuate, widening little below; umbilical region 

slightly impressed; inner lip reflexed and twisted, so as 

to form a small indistinct fold at its base; surface marked 

by fine, obscure lines of growth, which are crossed by 

impressed transverse striae separated by spaces about two 

or three times their own breadth near the middle of the 

outer whorl but becoming much more closely crowded 

toward the extremities. 

Length, 0.24 inch [6.1 millimeters}; breadth, 0.14 inch 

[3.55 millime~]; widest part of aperture, 0.07 inch [1.78 

millimeters]; breadth of same near upper extremity, only 

0.02 inch [0.5 millimeter]. 

The above description is drawn from a specimen found in the Fox Hills sandstone on Moreau River, S. Dak. ~ Oy~ichna-like shell found 

in the Cannonball marine member of the Lance 

formation agrees so well with 0. scitula in size, 

form, and sculpture that it is tentatively referred to that species, though it is slightly distorted by pressure and its true generic character is not determinable because ·the inner lip 

and columella are not visible. This specimen 

is figured. A much smaller specimen is probably the young of the same species. Four 

other fragmentary specimens representing as 

many localities are too poorly preserved for 

specific identification. 

Locality and position: The figured specimen 

was collected near Heart River in theSE. 1 sec. 

10, T. 138 N., R. 83 W., N.Dak., about 75 feet. 

below the top of the Cannonball marine member of the Lance formation. The small specimen was obtained in theSE. l sec. ·21, T. 136 

N., R. 82 W., 5 miles southeast of Strain post 

office, N. Dak. The other undetermined Oylickna specimens were collected on Heart River 

in sec. 8, T. 136 N., R. 84 W.; in the SW. 1 see. 

30, T. 130 N., R. 88 W., 7 miles north of Mor;. 

ristown, S.Dak.; in sec. 7, T. 22 N., R. 17 E., 

8 miles southeast of Lemmon, S. Dak.; and on 

Heart River, 1 mile west of Mandan, N.Dak. 

Genus CYLICIINBLLA Gabb. 

CyDehnella dakotensls Stanton, n. sp. 

Plate IX, figures lla and llb. 

Shell of moderate size, subcylindrical, with 

rather broadly round~ base; apex subtruncate, with narrow umbilicoid depression; aperture very narrow above, .slightly broadened 

. below; inner lip thickened and reflexed at the 

base; columella with two distinct folds; surface 

marked by numerous fine, impressed spiral 

lines, which are finer and more closely arranged 

on the middle third than toward the ends. 

Height about 15 millimeters; breadth 8 

millimeters. 

The genus Oylichnella, which ~ distinguished 

from Oylichna by the presence of two folds on 

the columella, is repreSented by a number of 

:recent and Tertiary species.· The Cretaceous 

forms referred to Oylichna -are often not well 

enough preserved to show the folds, and it may 

be that some of them really belong to Oylichnella. 0. dakotensis may be distinguished 

from Oyliihna scitula by the finer and more 

closely. arranged spiral striae, especially on the 

middle part of the shell, even when -the internal 

features are not visible. It is also larger and 

more nearly cylindrical. 

Locality and position: The type was collected in the Cannonball marine member of 

the Lance formation on Heart River about 12 

miles south of Almont, N. Dak., in the SW. i 

sec, 20, T. 136 N., R. 86 W. A smaller specimen doubtfully referred to this species was 

obtained from the same member on Heart 

River in the SW. l sec. 16, T. 136 N., R~ 84 W., 

10 miles north of" Flasher, N.Dak. 

.:,.: 
FAUNA. OF CANNONBALL MARINE MEMBER OF LANCE FORMATION. 49 

Phylum VEBTEBBATA. 

Class PISCES. 

Subclass ELASMOB:&ANCBD. 

J'amUy L.Al'rtiNIDAE. 

Genus LA:MNA Cuvier. 

Lamna cuspidata Agassiz. 

Plate IX, figures 12 and 13. 

Lamna tu8pidata Agassiz, Poissons fossiles, t. 3, p. 289, 

pl. 35, figs. 1-5; pl. 37a, :fig. 59, 1843. 

Fowler, New Jersey Geol. Survey Bull. 4, p. 43, figs. 

12-15, 1911. 

Odontaspis cuspidata (Agassiz) Eastman, Maryland Geol. 

Survey, Eocene, p. 105, pl. 14, figs. 1a, 1b, 6a, 6b, 

1901. 

NOTE-For more complete synonymy of this and the following species see U. S. Geol. Survey Bull. 179, 

and the Eocene and Miocene volumes of the Maryland Geological. Survey. 

Ten shark teeth representing as many localities in the Cannonball marine member of the 

Lance formation seem to be referable to 

Lamrw, cuspidata, which is reported from the 

Cretaceous, Eocene, and Miocene of both New 

Jersey and Maryland. 

Locality and position: The figured specimens came from Heart River 11 miles north of 

Flasher, N. Dak:.,,in sec. 8, T. 136 N., R. 84 W., 

and in a railway cut 1 mile east of MoiTistown, 

S. Dak:. Other specimens were found 5 and 6 

miles east of Flasher, in sees. 3 and 4, T. 134 

N., R. 83 W.; on Heart River 12 miles south of 

Almont, N. Dak:., in sec. 29, T. 136 N., R. 86 

W.; on the west bank of Missouri River 1 

mile south of ·Price and 19 miles north· of 

Mandan, N. Dak.; in sees. 20 and 21, T. 136 

N., R. 82 W.; in sec. 31, T. 135 N., R. 83 W.; 

and in sec. 10, T. 138 N., R. 83 W. 

Genus OTODUS Apssiz. 

Otodus obDquus Agassiz. 

Plate IX, figure 14. 

Otodm obliqum Agassiz, Poissons fossiles, t. 3, p. 267, pl. 

31, pl. 36, :figs. 22-27, 1843. 

Eastman, Maryland Geol. Survey, Eocene, p. 106, pl. 

15, figs. 1-4c, 1901. 

Otodm lanceolatum (Morton) Fowler, New Jersey Geol. 

Survey Bull. 4, p. 57, figs. 23-25, 1911. 

· A specimen, which is figured, agrees very 

well with the figure of a specimen of Otodus 

obliquus from the Eocene of Maryland. The 

species is reported in the Eocene and Miocene 

of Maryland and in the Cretaceous, Eocene, 

and Miocene of New Jersey .. 

Locality and position: In the Cannonball 

marine member. of the Lance formation near 

the top of Mitchell Butte, in sec. 7, T. 134 N., 

R. 83 W., about 3 miles east of Flasher, N. 

Dak. A smaller, less perfect specimen was 

obtained in sec. 24, T. 136 N., R. 68 W. 

PLATES I-IX. 

51 
PLATE I. 

Solemya billx White (p. 19). 

FIGURE la. Left side of specimen from Mandan, N. Dak. 

lb. Dorsal view of same. 

U.S.N. M. catalogue No. 32380. 

Nueula planbnarginata Meek and Hayden (p. 19). 

FIGURE 2. Gutta-percha squeeze from mold of left valve, X 2. 

U. S. N. M. catalogue No. 32381. 

3. Gutta-percha squeeze from mold of right valve, natural size. 

U.S.N. M. catalogue No. 32382. 

Nucula subplana Meek and Hayden (p. 20). 

FIGURE 4. Internal cast of left valye, natural size. 

5. Internal cast of right valve, natural size. 

6. Squeeze from mold of right valve, natural size. 

U.S.N. M. catalogue No. 32383. 

7. Right side of a small internal cast from another locality, natural size. 

U.S.N. M. catalogue No. 32384. 

Leda mansfteldl Stanton (p. 20). 

FIGURE 8. Type specimen, X 2. 

U.S.N. M. catalogue No. 32385. 

Yoldia scltula Meek and Hayden (p. 21). 

FIGURE 9. Left valve of type from Fox Hills sandstone, X 2. 

U.S.N. M. catalogue No. 302. 

10. Right valve of specimen from Cannonball member, X 2. 

U. S. N. M. catalogue No. 32386. 

Yoldia evansi Meek and. Hayden (p. 21). 

FIGURE 11. Cast of small right valve, X 2. 

U.S.N. M. catalogue No. 32387. 

Yoldia thomi Stanton (p. 21). 

FIGURE 12a. Left valve of type, X 2. 

12b. Dorsal view of both valves of same, X 2. 

12c. Interior of left valve of same, X 2. 

U.S.N. M. catalogue No. 32388. 

Nodosaria sp. (p. 18). 

FIGURE 13. Gutta-percha squeeze from small mold, X 4. 

U.S.N. M. catalogue No.32389. 

52 
U. S. GEOLOGICAL SURVEY PROFESSIONAl, PAPER 128 PLATE I 

lb 

la 

I 

2 

4 

5 

7 I 

8 

I 

10 13 

I 

12a 12b 

FAUNA OF THE CANNONBALL MARINE MEMBER OF THE LANCE FORMATION. 

43595°-21--5 

3 

6 

I 

9 -. 

I 

11 

I 

12c 
U. S. GEOLOGICAL SURVEY PROFESSIONAL PAPER 128 PLATE II 

Ib 

la 2a 

I 

4 

I 

3 

5 

6a 6b 

7 

_I 

9a 9b 9c 

8a 8b 

FAUNA OF THE CANNONBALL MARINE MEMBER OF THE LANCE FORMATION. 
PLATE II. 

Cucullaea shumardi Meek and Hayden (p. 22). 

FIGURE la. Cast of right valve retaining bit of shell near posterior end. 

lb. Hinge view of same. 

U.S.N. M. catalogue No. 32390. 

Cucullaea solenensis Stanton (p. 22). 

FIGURE 2a. Left side of an imperfect, somewhat distorted specimen. 

2b. Posterior view of same. 

U. S. N. M. catalogpe No. 32391. 

3. Left side of another specimen showing character of crenulations of free margiu . 

U. S. N. M. catalogue No. 32392. 

Trigonarca? hancocki Stanton (p. 23). 

FIGURE 4. Right valve (type), X 4. 

5. Left valve of another specimen, X 4. 

U.S.N. M. catalogue No. 32393. 

Glycimeris subimbricata (Meek and Hayden) (p. 23). 

FIGURE 6a. Left valve of typical form. 

6b . Hinge and interior of same: 

U.S.N. M. catalogue No. 32394. 

7. Larger, more convex, left valve. 

U.S.N. M. catalogue No: 32395. 

Crenella elongata Stanton (p. 25.) 

FIGURE Sa. Side view of type. 

Sb. Profile view of same. 

U . S. N. M. catalogue No. 32396. 

Crenella cedrensis Stanton (p. 25). 

FIGURE 9a. Right valve of type. 

9h. Profile view of both valves of same. 

9c. Sculpture near middle of right valve, X 4. 

U.S.N. M. catalogue No. 32397. 

53 
PLATE III. 

Pteria linguaeformis (Evans and Shumard) (p. 26). 

FIGURE 1. Small left valve. 

U. S. N. M. catalogue No. 32398. 

Pholadomya haresi Stanton (p. 20). 

FIGURE 2a. Right side of type. 

2b. Dorsal view of same. 

U. S. N. M. catalogue No. 32399. 

3. Anterior view of another specimen from squeeze of natural mold. 

U.S.N. M. catalogue No. 32400. 

Anatina subgracilis (Whitfield) (p. 26). 

FIGURE 4a. Left side of type from Pierre shale. 

4b. Dorsal view of same. 

U.S.N. M. catalogue No. 12253. 

5a. Left side of larger specimen from Cannonball member. 

5b. Dorsal view of same. 

U. S. N. M. catalogue No. 32401. 

Modiolus schallerensis Stanton (p. 25). 

FmuRE 6. Left valve (type), X 2. 

U.S.N. M. catalogue No. 32402. 

Crassatellites evansi Meek and Hayd~n (p. 28)o 

FIGURE 7a. Left side of a large well-preserved specimen. 

7b. Dorsal view of same. 

U. S. N. M. catalogue No. 32403. 

8. S::nallleft valve enlarged to show details of sculpture. 

U. S. N. M. catalogue No. 32404. 

0. Hinge of small specimen, X 2. 

U. S. N. M. catalogue No. 32405. 

Lucina cedrensis Stanton (p. 30)o 

FIGURE lOa. Left valve (type). 

lOb. Hinge and interior of same. 

U. S. N. M. catalogue No. 32406. 

lla. Left side of large imperfect specimen. 

llb. Profile view of same. 

U.S.N. M. catalogue No. 32407. 

54 
U. S. GEOLOGICAL SURVEY PROFESSIONAL PAPER 128 PLATE III 

1 2a 

2b 3 

4b 

4a 5b 

5a 

I 

6 7b 

7a 

I lOb 

8 

I 

9 lla llb 

FAUNA OF THE CANNONBALL MARINE MEMBER OF THE LANCE FORMATION. 
U . S. GEOLOGICAL SURVEY PROI<'ESSIONAL PAPER 128 PLATE IV 

la 

I 

3 

5 

6a 6b 

FAUNA OF THE CANNONBALL MARINE MEMBER OF THE LANCE FORMATION. 
PLATE IV. 

Pedalion lloydi Stanton (p" 24)~ 

FIGURE la. Small right valve, partly restored. 

lb. Interior of same showing part of hinge. 

2. Fragment showing part of hi11ge of left valve. 

U.S.N. M. catalogue No. 32408. 

Eriphyla? mandanensis Stanton (p. 28). 

FIGURE 3. Type, X 2. 

U. S. N. M. catalogue No. 32409. 

Arctica ovata Meek and Hayden (p. 27)o 

FIGURE 4. Hinge of left valve. 

U. S. N. M. catalogue No. 32410. 

5. Type of variety compressa, cast of right valve. 

U. S. N. M. catalogue No. 306b. 

6a. Type of species. Small right valve. 

6b. Hinge and interior of same. 

U.S.N. M. catalogue No. 306. 
FIGURE la. Imperfect left valve. 

lb. Hinge of same. 

PLATE V. 

Corbicula berthoudi White (p. 29). 

U. S. N. M. catalogue No. 32411. 

2. Hinge of a right valve. 

U.S. N; M. catalogue No. 32412. 

3. Cast of a left valve. 

U. S. N. M. catalogue No. 3241:3. 

Corbicula cytheriformis Meek and Hayden (p. 29). 

FIGURE 4a. Small left valve. 

4b. Hinge and interior of same. 

U. S. N. M. catalogue No. 32414. 

Callista (Dosiniopsis) nebrascensis (Meek and Hayden) (p. 30). 

FIGURE 5. Large right valve from Fox Hills sandstone. 

6. Hinge and interior of medium right valve from same formation. 

7. Small left valve from same formation. 

U. S. N. M. catalogue No. 32415. 

Sa. Left side of Meek and Hayden's type specimen from Pierre shale or Fox Hills sandstone. 

8b. Dorsal view of same. 

U. S. N. M. catalogue No. 343. 

9. Imperfect right valve from Cannonball member. 

U. S. N. M. catalogue No. 32416. 

10. Squeeze from mold of left valve from Cannonball member. 

U.S. N. M. catalogue No. 32417. 

Callista (Dosiniopsis) deweyi (Meek and Hayden) (p.- 31). 

FIGURE 11. Squeeze from mold of right valve. 

12. Cast of right vlave. 

U.S.N. M. catalogue No. 32418. 
U. S. GEOLOGICAL SURVEY PROFESSIONAL PAPER 128 PLATE V 

4a 

3 

5 

6 

Sa 8b 

10 11 

12 

FAUNA OF THE CANNONBALL MARINE MEMBER OF THE LANCE FORMATION. 
U. S. GEOLOGICAL SURVEY PROFESSIONAL PAPER 128 PLATE VI 

1 2a t 

2b 4 

3 

I 

5a 5b 

7 

6 

I I 

8a 8b 9a 

lOa lOb 

lla llb 

l 

14 15 

12 13 

FAUNA OF THE CANNONBALL MARINE MEMBER OF THE LANCE FORMATION. 
PLATE VI. 

Corbula mactriformis Meek and Hayden (p. 32). 

FIGURE l. Small left valve. 

2a. Right side of an internal cast. 

2b. Dorsal view of same. 

U.S.N. M. catalogue No. 32419. 

Panope simulatrix Whiteaves? (p. 32). 

FIGURE 3. Left valve. 

U.S.N. M. catalogue No. 32420. 

Teredo selliformis Meek and Hayden (p. 33). 

FIGURE 4. Right valve (type), X 4. 

U. S. N. M. catalogue No. 421. 

Teredo globosa Meek and Hayden (p. 33). 

FIGURE 5a. Right valve of type, X 4. 

5b. Posterior view of type, X 4. 

U.S.N. M. catalogue No. 422. 

Dentalium pauperculum Meek and Hayden (p. 34. ) 

FIGURE 6. Type specimen from Fox Hills sandstone, X 2. 

U.S.N. M. catalogue No. 311. 

7. Specimen from Cannonball member, X 2. 

U.S.N. M. catalogue No. 32421. 

Turbonilla? cordensis Stanton (p. 34.) 

FIGURE Sa. Dorsal vie·.v- of type, X 2. 

8b. Aperture view of same, X 2. 

U.S.N. M. catalogue No. 32422. 

Epitonium dakotense Stanton (p. 35). 

FIGURE 9a. Aperture view of-type, natural size. 

9b. Dorsal view of same. 

U.S.N. M. catalogue No. 32423. 

Lunatia obliquata Hall and Meek (p. 35). 

FIGURE lOa. Aperture view of large specimen from Cannonball member, natural size. 

lOb. Dorsal view of same. 

U.S.N .. M. catalogue No. 32424. 

Lunatia subcrassa Meek and Hayden (p. 36). 

FIGURE lla. Aperture view of a large specimen, natural size. 

llb. Dorsal view of same. 

U. S. N. M. catalogue No. 32425. 

Turritella haresi Stanton (p. 37). 

FIGURE 12. Aperture view of type, X 2. 

U.S.N. M. catalogue No. 32426. 

Anchura (Drepanochilus) americana (Evans and Shumard) (p. 37). 

FIGURE 13. Dorsal view of immature specimen from Fox Hills sandstone, natural size. 

U.S.N. M. catalogue No. 274. 

Anchura (Drepanochilus) americana var. pusilla Stanton (p. 38). 

FIGURE 14. Dorsal view of type, X 2. 

15. Aperture view of another specimen which lacks the wings, X 2. 

U.S.N. M. catalogue No. 32427. 

57 
PLATE VII. 

Anchura (Drepanochilus) perveta Stanton (p. 38). 

FIGURES la, lb. Opposite views of type specimen. 

2a, 2b, 3a, 3b. Similar views of two other specimens showing variations in,form and sculpture. 

U. S. N. M. catalogue No. 32428. 

Anchura (Drepanochilus) perveta var. gracilis Stanton (p. 39}. 

FIGURES 4a, 4b. Opposite views of type specimen. 

U . S. N. M. c~talogue No. 32429. 

Calyptraphorus septentrionalis Stanton (p. 39). 

FIGURES 5a, 5b, 5c, 5d. Opposite views of fragmentary type specimen, natural size and X 2. 

6. Spire of immature specimen, X 2. 

U.S.N. M. catalogue No. 32430. 

Cantharus (Cantharulus) vaughani (Meek and Hayden) (p. 40). 

FIGURES 7a, 7b. Opposite views of type specimen, natural size. 

U. S.N. M. catalog11e No. 255. 

Pyrifusus (Neptunella) newberryi (Meek and Hayden) (p. 40). 

FIGURES Sa, 8b. Opposite views of a small specimen, X 2. 

U. S. N. M. catalogue No. 32431. 

58 
U. S. GEOLOGICAL SURVEY PROFESSIONAL PAPER 128 PLATE VII 

la lb 2b 

2a 

3a 3b 

4a 4b 

I 

6 I l 

7a 7b 8a 8b 

FAUNA OF THE CANNONBALL MARINE MEMBER OF THE LANCE FORMATION. 
U. S. GEOLOGICAL SURVEY PROFESSIONAL rAPER 128 PLATE YIII 

la lb 3 

l 

5 7 

4 

8a 

llb 

I I I 

14b 14a 

8b lla 

13b 13a 

fr 

9 

I I l I 

10 12 15b 15a 16 

FAUNA OF THE CANNONBALL MARINE MEMBER OF THE LANCE FORMATION. 
PLATE VIII. 

Pyrifusus

1 

(Neptunella) gracilis Stanton (p. 41). 

F i GURES la, lb. Opposite views of thF type, natural size. 

U. S. N. M. cata]@gue No. 32432. 

. Levif~sus? tormentarius Stanton (p. 41). 

FIGURES 2a, 2b. Opposite views of the ype, X 2.() 

U.S.N. M. catal<Dgue No. 3.:.433. 

3. Dorsal view of anothet specimen, X 2. 

U.S.N. M. c::ttalogue No. 32434. 

P+psis hancocki Stanton (p. 42). 

FIGURE 4. Dorsal view of the type, X !2. 

U.S.N. M. catalt guo No. 32435. 

Fasciolaria? mandanensis Stanton (p. 43). 

FIGURE 5. Aperture view of type, natl al size . 

6. Dorsal view of same. [ 

U. S. N. M. catalogue No . 32436. 

7. Dorsal view of larger fragmef tary specimen. 

U.S.N. M. catall gue No. 32437. 

Fasc olaria? cordensis Stanton (p. 43). 

FIGURES Sa, 8b. Opposite views of tyge, X 2. · 

9. Dorsal view of speci~en with better-preserved vertical ribs, X 2. 

U. S. N. M. catal~g.ue No. 32438. 

10. Aperture view of spe<.i:imen doubtfully referred to this speciet:, X 2. 

U. S. N. M. catal ~gue No. 32439. 

FJsciolaria lloydi Stanton (p. 42). 

F 1 11b 0 · · f I · 1 · 'IGURES 1 a, . ppos1te v1ew o type specimen, natura Size. 

U. S. N. M. cataldgue No . 32440. 

Thrris cordensis Stanton (p. 45). 

FIGURE 12. Type specimen, X 2. I 

U.S.N. 1\f. catalJgue No. 32441. 

Fasciolaria (Mesorhytis) dakotensis Stanton (p. 43). 

FIGURES 13a, 13b. Opposite views oft pe, X 2. 

U.S.N. M. catal~gue No. 32442. 

14a, 14b. Op'i>osite views of~ ~all specimen, X 2. 

U.S.N. M. catalogue No. 32443. 

PsilocochlJs? occidentalis Stanton (p. 44). 

FIGURES 15a, 15b. Opposite views of t*pe, X 2. 

U. S. N. M. catal~gue No. 32444. 

ITurris Uoydi .Stanton (p. 45). 

FIGURE 16. Aperture view of type, X 2. 

U.S.N. M. I catalogue No. 32445. 

59 
PLATE IX. 

Turris? tormentaria Stanton (p. 45). 

FIGURES la, lb. Opposite views of type, natural size. 

U.S.N. M. catalogue No. 32446. 

Turricula janesburgensis Stanton (p. 45). 

FIGURES 2a, 2b. Opposite views of type, X 2. 

U.S.N. M. catalogue No. 32447. 

Turricula textilis Stanton (p. 46). 

FIGURES 3a, 3b. Opposite views of type, X 2. 

U. S. N. M. catalogue No. 32448. 

Turricula bacata Stanton (p. 46). 

FIGURE 4. Dorsal view of type, natural size. 

U.S.N. M. catalogue No. 32449. 

5. Aperture view of another-imperfect specimen, natural size. 

U. S. N. M. catalogue No. 32450. 

Turricula cincta Stanton (p. 46). 

FIGURES 6a, 6b . Opposite views of the type, X 2. 

U. S. N. M. catalogue No. 32451. 

Turricula? contorta (Meek and Hayden) (p. 47). 

FIGURE 7. Aperture view of medium specimen, natural size . 

8. Dorsal view of smaller specimen. 

U. S. N. M. catalogue No. 32452. 

Ringicula dubia Stanton· (p. 47). 

FIGURES 9a, 9b. Opposite views of the type, X 4. 

U.S.N. M. catalogue No. 32453. 

Cylichna scitula Meek and Hayden? (p. 48). 

FIGURE 10. Dorsal view of small specimen, X 3. 

U.S.N. M. catalogue No. 32454. 

Cylichnella dakotensis Stanton (p. 48). 

FIGURES lla, llb. Opposite views of type specimen, X 2 

U.S. N. M. catalogue No. 32455. 

Lamna cuspidata Agassiz (p. 49). 

FIGURE 12. Outer face of small tooth, natural size. 

U.S.N. M. catalogue No. 32456. 

13. Inner face of smaller tooth, X 2. 

U.S.N. M. catalogue No. 32457. 

Otodus obliquus Agassiz (p. 49). 

FIGURE 14. Inner face of tooth, natural size. 

U.S.N. M . catalogue No. 32458. 

60 
U. S. GEOI,OGICAL SURVEY PROl?ESSIONAL PAPER 128 PLATE IX 

la lb 

2a 2b 

4 5 

3a 3b 

T 

9a 

I I 

6a 6b 8 I 7 

9b 

1 

10 

I J lla 

llb 12 13 

FAUNA OF THE CANNONRALL MARINE MEMBER OF THE LANCE FORMATION. 
• 

CORALS FROM THE CANNONBALL MARINE MEMBER OF THE LANCE 

.FORMATION. . 

By THoMAs WAYLAND VAUGHAN. 

INTRODUCTION. 

Mr. T. W. Stanton has submitted to me for 

description a small lot of corals from the 

Cannonball marine member of the Lance formation. The species, all of which belong to 

closely related genera of the family Caryophylliidae, are as follows: 

Trochocyathus dakotaensis Vaughan, n. sp. 

Trochocyathus? neumani Vaughan, n. sp. 

Paracyathuslloydi Vaughan, n. sp. 

Paracyathus thomi Vaughan, n. sp. 

Paracyathus kayserensis Vaughan, n. sp. 

Steriphonotrochusleithensis Vaughan, n. sp. 

As several of 'the species have considerable 

resemblance to one another, a synopsis of some 

of the differences may aid in identification. 

Synopsis of differential characters of species of corals here 

described. 

Corallum short, height leBB than 8 millimetelll, costae 

unequal: 

Height leBB than longer diameter of calice, corallum 

straight, smaller costae indistinct or obsolete, 

Trochocyathus dakotaensis. 

Height slightly greater than longer diameter of calice, 

corallum curved, smaller costae well developed, 

distinct .................. Trochocyathusf neumani. 

Corallum elongate, exceeds 8 millimeters in height, costae 

equal: 

Corallum straight, inversely subconical: 

Calit!e shallow, depth about 1.75 millimeters, 

Paracyathus kayserensis. 

Calice about 3.5 millimeters deep: 

Pall very distinct. . . . . . . . Paracyathus lloydi. 

No pali, but rounded, more or less twisted 

lobes on inner edges of long septa, 

Steriphonotrochus leithensis. 

Corallum slightly curved in plane of shorter calicular 

axis, form subflabellate, greater transverse axis of 

calice longer than in any of the other species. 

Calice 5.5 millimetersdeep ... Paracyathus thomi. 

All the species are easily separable on external characters except Paracyathus lloydi and 

Steriphonotrochus leithensis, which are distinguishable chiefly by the differences in their 

septal margins. The type of P. lloydi is more 

compressed than S. leithensis, but this differ-

. ence may not be original. 

43595°-21-6 

These corals afford no basis for an inference 

as to the precise age of the sediments in which 

they were embedded, for they might be either 

of Tertiary or Cretaceous age. 

DESCRIPTION OF SPECIES. 

Famlly CARYOPHYLLIIDAE Verrill. 

Genus TROCHOCYATHUS Milne Edwards and Haime. 

Trochocyathus dakotaenis Vaughan, n. sp. 

Plate X, figures l=lb. 

Description of holotype: Corallum short, turbinate, straight; transverse outline eliiptical; 

basal scar of attachment rather large. Height, 

5.5 millimeters; greater diameter of the calice, 

8 millimeters; lesser diameter of the calice, 6.5 

millimeters; basal scar, 3.5 by 2 millimeters in 

diameter; depth of calice, about 2 millimeters. 

Wall rather stout, externally costate. Costae 

alternately distinct, well developed, and small 

or obscure. There are 24 large costae, all of 

which extend to the margin of the basal scar; 

low, triangular in profile; edges rather sharp, 

rather irregularly beaded. The small costae 

are low and thin; on each side of each of them 

there is a small raised line nearly equal in thickness and height to the costa but without any 

coiTesponding septum. 

Septa in four complete cyles; the primaries 

and secondaries are of the same thickness and 

length and reach the columella; the tertiaries 

are thinner and extend to or almost to the 

columella; the quaternaries are still thinner, 

are fused to the sides of the tertiaries, and 

usually reach about two-thirds the distance 

from the wall to the columella. Interseptal 

loculi open. Septal margins not very prominent; those of the largest septa exsert 1 millimeter; those of tertiaries and quaternaries 

low, subequal. Granulations on septal faces 

rather small, rather tall, and obtuse on the 

ends. 

Pali appear to be in . two crowns. A perfectly preserved naiTOW palus, rounded above, 

61 
62 SHORTER CONTRIBUTIONS TO GENERAL GEOLOGY, 1920. 

stands before one secondary septum, and Type: U. S. N. M. catalogue No. 32375. 

although the inner ends of the septa are broken, For reasons made obvious in the foregoing 

there appear to have been wide pali before the .description the genus of this species can not be 

tertiary septa. positively determined, but its costal charactere 

Columella rather small, papillate. and form show that it is distinct from any of the 

Locality and geologio occurrence: Station other corals collected in the Cannonball marine 

7962, river bluff in the SW. i sec. 17, T. 133 member of the Lance. 

N., R. 88 W., about 5 miles southeast of Kayser, 

N.Dak.; collected by W. T. Thorn, jr., September 18, 1912. Cannonball marine member of 

the Lance formation. 

Type: U. S. N. M. catalogue No. 32374. 

Trochocyathus? neumani Vaughan, n. sp. 

Plate X, figures 2-2c. 

Genus PARACYATHUS Milne Edwards and Haime. 

Paracyathus lloydi Vaughan, n. sp. 

Plate X, figures 3-3b. 

Description of holotype: Corallum somewhat 

compressed, inversely conical, straight; transverse outline elliptical; base rather sharppointed. !!eight, 13.5 millimeters; greater 

Descriptionofholotype: Corallumshort,sub- diameter of calice, 10.25 millimeters; lesser 

turbinate, curved, asymmetric; transverse out- diameter of calice, 7 millimeters; depth of 

line subelliptical; basal scar large, covered, calice, 3.5 millimeters. 

irregular in shape. Height on outside curvature 'Vall at its upper edge thin between the 

of corallum, 7.5 millimeters; height on inside distal ends of the septa. Costae correspond 

curvature, 6 millimeters; greater diameter of to all septa; they are low, rounded in profile 

calice, 6.5 millimeters; lesser diameter of calice, and equal or subequal, separated by narrow 

5 millimeters; depth of calice in plane of longer intercostal grooves; their sides and edges. 

calicular diameter, about 2 millimeters. granulate, the granulations elongate tra.nsW all rather thin between the distal ends of versely to the costal courses. 

the septa, externally rather strongly costate. Septa 50 in number, four complete cycles 

Costae correspond to all septa; distinct almost and two quinaries; primaries and secondaries 

to the tip of the base; rather thick; their sides equal, appreciably but not greatly thicker than 

steep, interspaces narrow; edges obtuse, beaded; the members of the higher cycles, extending to 

the beads with their longer axes transverse to or almost t'o the columella; tertiaries and qua-. 

the costal courses; every other or every fourth ternaries decidedly thin and shorter than the 

costa somewhat more prominent than the inter- members of the lower cycles; quaternaries seem 

mediate costae. to join the tertiaries about two-thirds the disSepta about 45; the fourth cycle seems almost tance from the wall to the columella. Interbut not quite complete, but the holotype is not septal loculi relatively wide in upper part of 

in perfect condition and there may be a few the calice, wider than the thickness of the 

more septa than were counted; the normal septa. The septa are not nearly so thick, only 

nu~ber is probably f~ur complete cycles. Pri-~ ~alf or less than half as thi~k as the correspondmaries and secondaries equal or subequal; ter- 1ng costae. Septal margins not prominent, 

tiaries thinner; quaternaries shorter and thinner exsert only about 0.5 millim~ter. Granulathan the tertiaries. Septal margins very tions on the septal faces tall, rather crowded, 

slightly exsert. nipple-shaped or subcylin<h,-ical. 

Palar characters indefinite, a condition which Pali well developed and conspicuous. The 

explains the doubtful identification of the genus widest form a crown before the tertiary septa; 

of the species. these stand up almost half the depth of the 

Columella small. calice above the bottom of the calicular fossa, 

Locality and geologic occurrence: Station are rounded above, and are a little less than 

7964, sec. 31, T. 133 N., R. 88 W., about 6 miles 0.5 millimeter wide. Narrower pali seem to 

south of Kayser, N. Dak.; collected by L. M. be present before the secondary and primary 

Neuman, September 23, 1912. Cannonball septa, and these are not sharply differentiated 

marine member of the Lance formation. from the columellar papillae. 
E'AUNA OF CANNONBALL MARINE MEMBER OF LANCE FORMATION. 63 

The top of the colum~lla is sunken in a deep, 

rather narrow fossa; its upper surface is papillate; the papillae are small and rodlike, and are 

not sharply differentiated from the innt'rmost 

palar crowns. 

Locality and geologic occurrence: Station 

7961, in the NE. i SW. l sec. 5, T. 132 N., R. 

88 W., about 9 miles southwest of Leith, N. 

Dak.; collected by W. T. Thorn, jr., September, 

1912. Cannonball marine member of the 

Lance formation. 

Type: U.S.N. M. catalogue No. 32376. 

Paracyathus thomi Vaughan, n. sp. 

Plate X, :figures 4-4d. 

Description of holotype: Corallum subflabellate; slightly curved in the plane of the 

shorter transverse axis of the calice; transverse outline elliptical; base with a distinct, 

elongate, but not very large scar of attachment. Height, 13.5 millimeters, measured 

with callcular margin in a horizontal plane. 

As the corallum has been slightly crushed the 

measurements of calicular diameters ~t the 

calicular margin are not as they would be in an 

undamaged specimen, but they are as follows: 

Greater diameter, 12.5, millimeters; lesser diameter, 7.75 millimeters. At a height of 8.5 millimeters above the base the diameters are as follows: Greater diameter, 10 millimeters; lesser 

diameter, 7.75 millimeters. The greater cliameter normally is between 1.25 and 1.30 times as 

long as the lesser diameter. Basal scar 3 millimeters long and 1 millimeter wide. Depth of 

calice, 5.5 millimeters. 

Wall rather thin at its upper edge. Costae 

well developed, thicker than the width of the 

intercostal furrows, subequal in thickness and 

height, edges subacute, sides granulate. Although the costae are somewhat thicker than 

the corresponding septa inside the calicular 

cavity, the difference between the thickness of 

septa and ·costae is not so pronounced as in 

Paracyathus lloydi. 

Septa 58 in number, four complete cycles and 

10 quinaries; primaries and secondaries equal 

or subequal, considerably thicker than the 

members of the higher cycles, extending to the 

columella; tertiaries and qua ternaries thinner 

and shorter than the members of the lower 

cycles; there are no obvious septal groups; of 

the quinaries it can only· be said that they are 

small. In terseptalloculi open and rather wide in 

the upper part of the calice, slightly wider than 

the thickness of the larger septa, much wider 

than the thickness of the smaller septa. Septa 

not greatly different in thickness from their corresponding costae. Margins only moderately 

exsert, taller ones project about 1.2 millimeters. 

Granulations on the septal faces rather crowded 

and rather tall, nipple-shaped or subcylindrical. 

There are before the tertiary septa rather 

wide, very thin, curly pali, which stand fairly 

high up in the calice; pali before the secondary 

and primary septa are not so definite, but there 

are on the lower part of the inner edges of at 

least some of these septa processes or curly 

lobes that appear to ~ade into the columellar 

papillae, as is usual in species of Paracyathus. . 

. The columella is at the bottom of a deep, 

narrow fossa; it is rather small, and its upper 

surface is finely papillate, the columellar papillae not sharply distinguishable from the innermost small pali. 

Locality and geologic occurrence: Station 

7961, in the NE.! sec. 5, T. 132 N., R. 88 W., 

ahout 9 miles southwest of Leith, N. Dak.; 

collected by W. T. Thorn, jr., September, 1912. 

Cannonball marine member of the Lance formation. 

Type: U.S.N. M. catalogue No. 32377. 

Paraeyathus kayserensis Vaughan, n. sp. 

Plate X, :figure 5-5b. 

Description of holotype: Corallum inversely 

conical, straight; transverse outline broadly 

elliptical; basal scar distinct. Height, 9.5 millimeters; greater diameter of the calice, 7.5 

millimeters; lesser diameter of the calice, 6.75 

millimeters; basal scar, about 1.25 millimeters 

in diameter; depth of calice, about 1.75 millimeters. 

Wall rather strong but not especially thick, 

externally costate. Costae distinct but not 

prominent, correspond to all septa, equal; intercostal grooves nar.row; costal edges subacute; faces with some granulations. 

Septa 48 in number, four complete cycles; 

primaries and secondaries equal, a little thicker 

than the tertiaries and quaternaries; the quaternaries seem as a rule to fuse to the sides of the 
64 SHORTER CONTRIBUTIONS TO GENERAL GEOLOGY, 192()j1. 

included tertiary septum. Interseptal loculi 

wide, much wider 'than the thickness of the 

septa. The septa are thin, not nearly so thick 

as the corresponding costae. Septal margins 

not at all exsert. Granulations on the septal 

faces unequally distributed and of unequal 

height; some are tall and slender, others low 

and conical. 

Wide, rather thin, more or less sinous pali 

before the tertiary septa; before the primaries 

and secondaries apparently there are narrow, 

small pali which are not sharply distinct from 

the columellar papillae. 

Columella rather large, about 1.5 by 2 millimeters in diameter, upper surface papillate, the 

papillae rather small. 

Locality and geologic occurrenQe: Station 

7965, in T. 113 N., R. 88 W., about 6 miles 

south of Kayser, N. Dak.; collected by W. T. 

Thorn, jr., September 23, 1912. Cannonball 

marine member of the Lance formation. 

Type: U.S. N. M. catalogue No. 32378. 

Genus STERIPHONOTROCHUS Vaughan. 

Steriphonotrochus leithensis Vaughan, n. sp. 

Plate X, figures 6-6b. 

Description of holotype: Corallum Inversely 

conical, straight, transverse outline broadly 

elliptical; base a rounded tip on which a few 

septa are visible. Height, 13.5 millimeters; 

greater diameter of the calice, 9 millimeters; 

lesser diameter of the calice, S.5 millimeters; 

depth of calice, about 3.5 millimeters. 

Wall not very thick, externally· costate. 

Costae distinct but low, equal, separated by 

narrow intercostal grooves, edges rather obtuse 

but not flat. 

There are 48 septa, four.~omplete cycles; all 

septa equal or subequal at:.~he wall and at least 

22, probably one or two ~*tore, extend to the 

columella-that is, the primary, secondary, and 

most or all of the tertiary septa reach the 

columella; the quaternaries are shorter. Although the septa are not weak, their thickness 

at the wall is less than the width of the interseptalloculi, and they are not so thick as the 

corresponding costae. Septal margins slightly 

exsert, about 0.75 millimeter. There are no 

clearly differentiated pall in the holotype of 

this species, but beginning about 1.25 millimeters below the top of the septal arches and 

continuing to the periphery of the columella 

there are on the inner edges of all the long septa 

curly lobes-there ar~ about six of these lobes 

within a distance of about 3 millimeters measured along the septalmargin; therefore a lobe 

and an interlobar spac8J.a.re about 0.5 millimeter 

across on an average. ~:i ;. Some of the lobes are 

curled so that the measure perpendicul~r to the 

septal plane exceeds th:at parallel to it. These 

lobes are smooth edged and resemble the lobes 

on the. inner ends of some septa in some species 

of Paracyathus~· they do not resemble the septal dentations of Montlivaltia, ..Antillia, etc. 

Septal faces with low granulations. 

Columella well developed, of moderate size, 

almost 2 millimeters in diameter; upper surface finely papillate; papillae not sharply distinguishable from the innermost septal lobes. 

Locality and geologic occurrence: Station 

7963, north of the NW. i sec. 11, T. 132 N., 

R. 88 W., about 7 miles south of Leith, N.Dak.; 

collected by W. T. Thorn, jr., and L. M. Neuman, September 20, 1912. Cannonball marine 

member of the Lance formatioJ:l. 

Type: U.S.N. M. catalogue No. 32379. 
PLATE X. 

65 
FIGURE 1. Corallum, X 2. 

la. Costae, X 4. 

lb. Calice, X 4. 

Trochocyathus dakotaensis Vaughan, n. sp. (p. 61). 

U.S.N. M. catalogue No. 32374. 

Trochocyathus? neumani Vaughan, n. sp. (p. 62). 

FIGURE 2, 2a. Two views of the corallum, each X 2. 

2b. Costae of edge, X 4. 

2c. Calice, X 4. 

U. S. N. M. catalogue No. 32375. 

FIGURE 3. Corallom, X 2. 

3a. Costae, X 4. 

3b. Calice, X 4. 

Paraeyathus lloydi Vaughan, n. sp. (p. 62). 

U.S.N. M. catalogue No. 32376. 

Paracyathus thomi Vaughan, n. sp. (p. 63). 

FIGURES 4, 4a, 4b. Three views of the corallum, each X 2. 

4c. Costae, X 4. 

4d. Calice, X 4. 

U.S.N. M. catalogue No. 32377. 

FmuRE 5. Corallum, X 2. 

5a. Costae, X 4. 

5b. Calice, X 4. 

Paracyathus kayserensis Vaughan, n. sp. (p. 63) •. 

U.S.N. M. catalogue No. 32378. 

FIGURE 6. Corallum, X 2.· 

6a. Costae, X 4. 

6b. Calice, X 4. 

Steriphonotroehus leithensis Vaughan, n. sp. (p. 64). 

U.S.N. M. catalogue No. 32379. 

66 
U. S. GEOLOGICAL SURVEY PROFESSIONAL PAPE R 128 PLATE X 

1 la 2 2a 

lb 

2c X4 

3 

3a 2b 

3b 

4 4a 4b 

5a X4 

4c 4d 

5 

6a 

6 

6b 5b 

CORALS OF THE CANNONBALL MARINE MEMBER OF THE I,ANCE FORMATION.