Additions to the Flora of the 

Spotted Ridge Formation 

in Central Oregon 

GEOLOGICAL SURVEY PROFESSIONAL PAPER 274-I 

Additions to the Flora of the 

Spotted Ridge Formation 

in Central Oregon. 

By SERGIUS H. MAMAY and CHARLES B. READ 

A SHORTER CONTRIBUTION TO GENERAL GEOLOGY 

G E 0 L 0 G. I CAL S U R V E Y P R 0 F E S S I 0 N A L P A P E R 2 7 4-I 

The U. S. Geological Sur'vey' s previously 

undescribed collection of fossil plants 

from the Spotted Ridge formation is 

fully described and illustrated, 

including three new species. 

UNITED STATES GOVERNMENT PRINTING OFFICE, WASHINGTON : 1956 
UNITED STATES DEPARTMENT OF THE INTERIOR 

Fred A. Sea ton, Secretary 

GEOLOGICAL SURVEY 

Thomas B. Nolan, Director 

For sale by the Superintendent of Documents, U. S. Government Printing Office 

Washington 25, D. C. 
CONTENTS 

Page 

Abstract------------------------------------------------------------------------------------------------------ 211 

Introduction-------------------------------------------------------------------------------------------------- 211 

Stratigraphy of the Grindstone-Twelvemile Creeks Paleozoic Inlier___________________________________________________ 212 

Systematic descriptions_________________________________________________________________________________________ 214 

?Lepidodendroid branchlet---------------------------------------------------------------------------------- 214 Genus M esocalamites Hirmer _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ 214 

Genus Phyllotheca Brongniart ______________________________________________________________________________ ~ 216 

Genus AsterophylUtes Brongniart----------------------------------------------------------------------------- 218 Genus Pecopteris Brongniart __________________________________________ ·_ _ ___ _ _ ____ ____ __ ___ _ ____ __ ___ _ _ ___ _ _ _ 219 

Genus Dicranophyllum Grand'Eury ________________________________________________________ ------- __ __ _____ _ _ 219 

Problematica---------------------------------------------------------------------------------------------- 221 I>iscussion____________________________________________________________________________________________________ 222 

Literaturecited------------------------------------------------------------------------------------------------ 223 

Index-------------------------------------------------------------------------------------------------------- 225 

ILLUSTRATIONS 

[Plates 34-37 follow index] 

PLATE 34. Mesocalamites and Phyllotheca. 

35. Phyllotheca paulinensis Mamay and Read, n. sp. 

36. Pecopteris, 'I Schizopteris, ? Cordaianthus, Asterophyllites, and ?lepidodendroid branchlet. 

37. Undetermined roots and Dicranophyllum rigidum Mamay and Read, n. sp. 

• 

A SHORTER CONTRIBUTION TO GENERAL GEOLOGY 

ADDITIONS TO THE FLORA OF THE SPOTTED RIDGE FORMATION IN CENTRAL OREGON 

By SERGros H. MAMAY and CHARLES B. READ 

ABSTRACT 

The U. S. Geological Survey's previously undescribed collection of fossil plants from the Spotted Ridge formation ( Pennsylvanian) in central Oregon is fully described and illustrated. 

This includes three new species: Mesooalamites crookensis, 

n. sp., PhyZlotheca paulinensis, n. sp., and DicranophyZZum 

rigidum, n. sp. The collection also contains an abundance of 

Pecopteris oreuonensis Arnold and M esocaZamites hesperius 

(Arnold) Mamay and Read, as well as a minor representation 

of a few other plants, some problematical. The flora contains 

unusually few species, and comparisons of its components with 

other Pennsylvanian floras prompt the conclusion that on the 

basis of the fossil plants alone, the precise age of the Spotted 

Ridge formation within the Pennsylvanian cannot be determined with any great degree of confidence. 

INTRODUCTION 

In 1938 S. A. Berthiaume and C. W. Merriam discovered abundant :fossil plants in a sequence o:f upper 

Paleozoic sedimentary rocks exposed on the ranch o:f 

Orin Mills, about 15 miles southeast o:f Paulina, in 

Crook County, Oreg. The following year Merriam and 

Read revisited the locality and made a large collection 

o:f the :fossil plants. The announcement o:f this discovery was published by Read and Merriam ( 1940) ; this 

preliminary report included a tentative list o:f the components o:f the flora, along with a short discussion o:f 

their geographic relations and stratigraphic implications. 

The geology o:f this region was later described in a 

report by Merriam and Berthiaume (1943), in which 

this Paleozoic sequence was divided into three stratigraphic units: the Coffee Creek, Spotted Ridge, and 

Coyote Butte :formations. On the basis o:f marine invertebrate :fossils, the Coffee Creek :formation was assigned to the lower Carboniferous, and the Coyote 

Butte :formation, to the Permian. The interposed 

Spotted Ridge :formation, however, was :found to be 

barren o:f invertebrate :fossils; and consequently, the determination o:f its age was made on the basis o:f its :fossil 

plant contents. This :formation was assigned to the 

Pennsylvanian, with Pottsville age provisionally indicated. A more detailed account o:f the stratigraphy of 

this region is given on page212. 

In 1949 Chester A. Arnold and a group :from the University o:f Michigan visited this locality and made a 

collection o:f the :fossil plants. This collection was recently described by Arnold (1953), who has advised 

us (1954, oral communication) that the University o:f 

Michigan collection was obtained at the site o:f Read 

and Merriam's original excavation; thus, there is no 

doubt that the two collections represent portions o:f the 

same flora. 

Arnold described two new species. The first, Pecopteris oregonensis Arnold, is a delicate :fernlike plant 

with dactylothecoid :fructifications and highly variable 

foliage; fragments of this plant make up all but a 

small part o:f the total plant material in both the University of Michigan and the U. S. Geological Survey's 

collections. The other, 0 alamites hesperius Arnold, is 

a calamarean stem species based on internal casts; the 

foliage and :fructifications are unknown. Arnold also 

briefly described the detached vegetative and reproductive parts o:f P_hyllotheca sp.; although he made no 

specific determination, Arnold reiterated the opinion 

given by Read and Merriam that the Plvyllotheca material most closely resembles the Tnrkish species P. rallii 

Zeiller. 

In their preliminary analysis o:f this flora, Read and 

Merriam listed the genera .Asterophyllites, Oalatllllites, 

Dactylotheca, DicraJIWphyllwm, Phyllotheca, and Sphenopteri8 (several species), as well as "Material referable 

to two new genera of cordaitalean affinities" and "some 

problematica not definitely assignable at present" 

(Read and Merriam, 1940, p. 109'). Arnold, however, 

included the dacty lothecoid fructifications, as well as 

sterile :foliage reminiscent o:f certain sphenopterid 

species within the specific limits o:f Pecopteris oregonensis. Arnold reported neither Asterophyllites nor 

cordaitalean material; and although :fragments o:f Dicranophyllum and Phyllotheca were present in the 

University of Michigan's collection, they were appar211 
212 CONTRIBUTIONS TO GENERAL GEOLOGY 

ently too incomplete and poorly preserved to warrant 

full description or specific determinations. 

The U. S. Geological-Survey's collection of Spotted 

Ridge plants has not yet been described in full detail; 

nor, to the best of the writers' knowledge, have further 

collections of this material been made. It thus seems 

that the publication of a full description of this collection and complete illustration of the flora, as a supplement to Arnold's studies, should constitute a note of 

more than casual interest. The flora is especially significant in view of the rarity of Pennsylvanian plant 

records in the Western United States, as contrasted 

with their abundance.in the Eastern and Midwestern 

States, and because of the presence of certain floristic 

components that occur only rarely in any of the known 

Pennsy I vanian floras. A detailed know ledge of the 

flora of the Spotted Ridge formation also appears desirable as a complement to Merriam and Berthiaume's 

description of the geology of the area involved, especially since thefr determination of the age of the 

Spotted Ridge formation was so entirely dependent on 

this fossil-plant collection. The descriptions that follow are presented for the purpose of amplifying as 

much as possible our knowledge of the Spotted Ridge 

flora, primarily by discussion of those floristic elements 

not found by Arnold. 

STRATIGRAPHY OF THE GRINDSTONE-TWELVEMILE 

CREEKS PALEOZOIC INLIER 

The Grindstone-Twelvemile Creeks Paleozoic inlier, 

Crook County, Oreg., comprises parts ofT. 18 S., Rs. 24: 

and 25 E., and T. 19 S., Rs. 24 and 25 E., and is about 

15 miles southeast of Paulina. On the Upper Mills 

Ranch in an area of about 20 square miles, strongly 

folded Mississippian, Pennsylvanian, and Permian 

strata are exposed. Resting unconformably on these 

older rocks are less strongly folded Triassic and Jurassic strata. Nearly horizontal middle and late Tertiary 

extrusive volcanic and pyroclastic rocks apparently 

once completely overlay the Paleozoic and Mesozoic 

sequence but have now been locally eroded. 

First observed and reported by Packard ( 1928, 

1932) , the general stratigraphy and structure of the 

Paleozoic inlier was first described in some detail by 

Merriam and Berthiaume ( 1943). The following 

statement of the stratigraphic sequence is transcribed 

from their more detailed account. 

COFFEE CREEK FORMATION, LOWER CARBONIFEROUS 

General description.-The Coffee Creek formation is named 

for exposures on a minor tributary of this name which enters 

Grindstone Creek south of 'Y a de Butte. A.t the type section 

in sec. 30, T. 18 S., R. 25 E. ~ mile east of the spring at Mills 

sheep camp a line of limestone outcrops trend roughly northeast-southwest. In general the formation consists of wellbedded fairly pure limestones, caTbonaceous limestones, argilla-

·ceous to sandy limestones, and calcareous sandstone. Exposures of the type Coffee Oreek area were traced intermittently 

along the strike for a distance of about 11;4 miles from locality 

93 on the south to locality 98 on the north. * * * 

Thiokness.-Estimates of thickness are greatly handicapped 

by deformation, and nowhere has the base of this formation 

been recognized. Conservative figures of 900 to 1000 feet are 

based on width of outcrop in the anticlines of Coffee Creek, and 

north of Coyote Butte, where in the last instance the strata 

stand in nearly vertical position. 

Stratigraphio relations and age.-The Coffee Creek formation 

represents the oldest Paleozoic division recognized in this 

region. Judging from the lithologic and paleontologic criteria 

its relationship to the overlying Spotted Ridge Pennsylvanian 

is one of disconformity. Overlap of the partly land-laid 

Spotted Ridge upon the Coffee Creek is suggested by distribution of the two units, though stratigraphic evidence is inadequate. In some localities the Coffee Creek is directly overlain 

by either Permian or Triassic beds. These unconformities are 

discussed below. The age of the Gigantella horizon is based 

on the listed fa una and is Lower Carboniferous, roughly Visean, 

in terms of the British succession. That the lower sands of 

this division are not older than Lower Carboniferous is attested by presence of the product Striatitm·a, not known in 

strata of greater age. The preliminary faunal list is as 

follows: 

Dibunophyllum oregonensis Merriam 

Lithostt·otion ( f,ithostrotion) packardi Merriam 

Lithostrotion ( Siphonodendron) oregonensis Merriam 

Oampophyllum readi Merriam 

Gigantella sp. 

Striatifera sp. 

Spirifer cf. striq,tus (Martin) 

Tetrataxis sp. 

Small loxonemoid gastropods 

Lithistid sponge spicules 

A.ll but the spirifer are very abundant, Striatifera the commonest form ranging throughout. Gigantella bas been found 

only in the key limestone bed about 45 feet below the top of 

the formation as shown at locality 2, where the bed is crowded 

with these shells in association with the corals listed. The 

Foraminifera, small gastropods, and sponge spicules are abundant at the same horizon; they are silicified and can be prepared 

by the acid-etching treatment. 

SPOTTED RIDGE FORMA'I'JON, PENNSYLVANIAN 

General description.-Sediments of the Spotted Ridge formation are exceedingly variable in both vertical and horizontal 

direction, ranging from compact mudstones and cross-bedded 

sandstones to very coarse boulder conglomerates. Locally 

much bedded chert is present. The members thicken and thin 

in various directions or may pinch out completely within a short 

distance. Good exposures are rare because the outcrop belts 

are in alluviated valleys or somewhat depressed areas between 

strike ridges formed by more resistant Permian rocks. The 

best exposures are in the type section on the west flank of 

Spotted Ridge, extending south about 2 miles to locality 83. 

Plant-bearing sandstones and mudstones.-Sandstones with 

much carbonaceous material and recognizable plant remains 

appear to range throughout the formation, while the lenticular 

plant-bearing mudstones were found only in the upper part. 

The lowest sands with plants occur at locality 96 near the 

Coffee Creek contact. These basal deposits are sands of 

medium-grain and light neutral-gray color on fresh surface, 

weathering to various tones of limonite brown. Feldspar grains 

are abunda:at. Plant remains range from finely divided carbonaceous debris to flattened stems several inches in length. 
ADDITIONS TO THE FLORA OF THE SPOTTED RIDGE FORMATION IN CENTRAL OREGON 213 

That a similar facies persists locally or recurs in some situations is indicated by the presence of plant-bearing beds of much 

the same character at locality 108 within about 75 feet of 1the 

top of this division, possibly 900 feet stratigraphically above 

the locality :first mentioned. 

Lenticular distribution of sedimentary types is appartmt 

within the plant-bearing deposits. At the main plant locality 

on the west side of Spotted Ridge are :fine sandstones, siltstones, 

and mudstones in varying order within a thickness of 5 feet. 

Intergradation from one layer to another is recognized. ]'ollowing the same approximate horizon southward a distalllce 

of lh mile to locality 7 one finds crossbedded sandstone lenses 

within a heavy conglomerate including 2-foot boulders. Some 

of the finer sands here contain plant remains in direct assodation with small nuculid bivalves, small gastropods, and what 

appears to be a scaphopod about lh inch in length. 

The lenticular mudstones and siltstones at locality 115 are! of 

an unusual shade of medium-grayish olive green. Lamination 

is usually not well defined, and :fissility is undeveloped. ~l'he 

sediment is very compact and brittle. In general the plants 

lie more or less parallel to bedding though occasional leaves 

and stems are decidedly oblique in position. The plants occur 

as coaly films; stems are much flattened but retain evidences 

of vascular structure. Impressions of leaves below the earbonaceous films are sharply defined. The fine state of preBervation of the dark leaves surrounded by a relatively light 

matrix lends added value to the plants for study purposes. 

While certain tongues or lenses within the plant-bearing beds 

are marine or brackish it is believed that most of the St~diments in this facies are land-laid, though an estuarine origin 

in part is not unlikely. The plants do not appear to have suffered transportation; in fact, some calamite stalks with whorls 

of twigs appear to be essentially in position of growth. * * * 

Thicknoos.-In view of intense folding and lack of continuous 

outcrop it was not found possible to arrive at accurate figures 

regarding thickness. Variability in lithology from place to place 

along the outcrop belts suggests great differences in thickness 

of the entire section and of its individual members. This applies particularly to the conglomerates, and to the cherts, which 

last are entirely absent at certain localities in horizons where 

they would be expected. Judging roughly from width of outcrop the formation at the type section, extending through locality 115, is probably 1000 feet thick. Southward along 

Twelvemile Creek the thickness is at least 1000 feet, while· on 

the north slope of Coyote Butte it may, with the included che·rts, 

exceed 1500 feet. 

Stratigraphic relations and age.-"-The lowest exposed Spotted 

Ridge beds recognized lie in the vicinity of locality 96 where 

plant-bearing sands were found within a few feet of a wellexposed limestone bed of the Gigantella horizon and thereJcore 

near the top of the Coffee Creek Lower Carboniferous. Uplift 

and emergence following deposition of the purely marine upper 

Coffee Creek is suggested by the probable terrestrial or estuarine 

nature of these lower Spotted Ridge deposits. Nothing conclusive has, however, been determined regarding the magnitude of 

the break separating Coffee Creek from Spotted Ridge beyond 

the fact that the marine faunas of the upper Coffee Creek are 

of Lower Carboniferous age, while floral evidence suggests a 

Lower Pennsylvanian age for the upper Spotted Ridge beds. 

The Coyote Butte Permian is unconformable upon the Spotted 

Ridge. Judging from fossil evidence there is in all probability 

a hiatus representing a portion of the Lower Permian and perhaps most of the Upper Pennsylvanian. A sharply defined contact between Spotted Ridge sandstones and relatively pure limestone of the Coyote Butte is exposed at locality 105 in the 

southwestern portion of the area. There is here a slight angular 

discordance between the two divisions. The Coyote Butte formation is regarded as marine in contrast to the partly estuarine~ 

terrestrial and alluvial or delta-plain character of the underlying Spotted Ridge. 

While no determinable marine fossils were discovered in 

the Spotted Ridge formation, reliable evidence regarding its 

age is provided by the flora found at locality 115 in a horizon 

within the upper 400 feet. * * * 

Read and Merriam conclude that the flora is Lower Pennsylvanian, stafing, however, that the possibility of its being Upper 

Pennsylvanian cannot be completely ruled out. If the flora 

ultimately proves to be Lower Pennsylvanian, it is likely that 

no great gap exists between the Coffee Creek and Spotted Ridge 

formations. 

COYOTE BUTTE FORMATION, PERMIAN 

General description.-The youngest Paleozoic beds of the area 

comprise a sequence in which massive limestones form the most 

conspicuous exposures. These produce prominent ridges, buttes, 

and small circular hills or knobs subsidiary to the main ridge 

slopes. Steeply dipping strata forming the crest of Coyote 

Butte near the southern limit of the map constitute the type 

section of the division. The Coyote Butte beds here lie in the 

north limb of a tight syncline overturned toward the south. 

Another bold outcrop of the formation is found in the belt of 

limestone extending north-northeast about 4 miles from the 

vicinity of Tuckers Butte to the spring at locality 92. A third 

area of Permian beds includes the limestone exposures in the 

northeast portion of the map, one tongue of which extends 

southwest 'beyond Twelvemile Creek where it is covered by 

Tertiary lava. 

At the type section the lower portion of the Coyote Butte is 

generally a light olive-gray limestone, often crinoidal and locally 

containing abundant fusulinids. Higher in the section, at the 

summit of Coyote Butte, the limestone becomes purer, finergrained, deep olive-gray and more distinctly bedded. In this 

upper portion ·there are fewer fusulinids, while brachiopods are 

common. * * * 

Limestones of the Coyote Butte formation are interbedded 

with large amounts of sandstones. Furthermore the discontinuous nature of some of the limestone exposures leads to the 

impression that these deposits are lenticular within the more 

arenaceous facies. Generally speaking, exposures of the sands 

are poor, while the limestones form prominent linear or circumscribed exposures. Northeast of locality 123 in the center 

of the map several zones of sandstone float alternate with fusulinid limestones. * * * 

Thickness.-At the type section on Ooyote Butte approximately 900 feet of the Permian beds is exposed. Estimates 

of thickness on Spotted Ridge and north of Tuckers Butte are 

approximately the same. However, exact thicknesses cannot 

be given since bedding is poor and folds within the massive 

limestone are difficult to work out. Where the formation is 

largely arenaceous the exposures are poor. Unconformable 

relation of the Permian to overlying beds further eliminates 

true thickness estimation. 

Stratigraphic relations and aue.-The Ooyote Butte formation is unconformable on the Spotted Ridge Pennsylvanian, 

as suggested by pinching out of the Pennsylvanian strata in 

sec. 5, T. 19 S., R. 25 E., where the contact between Coyote 

Butte limestone and the Lower Carboniferous Coffee Creek 

formation is apparently depositional. At locality 105 north 

of Tuckers Butte an exposure of the lower contact of the Permian shows a slight angular discordance and a definite truncation of the conglomeratic and sandy beds of the underlying 
214 CONTRIBUTIONS TO GENERAL GEOLOGY 

formation. On the basis of lithology and position the latter 

beds are presumed to be the Spotted Ridge formation. Furthermore, on the west side of Spotted Ridge and at several other 

localities the basal Coyote Butte strata are very pebbly limestones and calcareous conglomerates, probably indicating reworking of subjacent Pennsylvanian clastics. 

Fusulinids, corals, and brachiopods from the Coyote Butte 

formation indicate a Permian age for these beds. Several 

faunal zones are undoubtedly represented but have not been 

. differentiated in view of the complex structure and lenticularity 

of sedimentation. More refined studies of structure, stratigraphy, and sedimentation will be required to work out the 

details of this zonation. Since the Spotted Ridge plant-bearing beds a short distance below the Coyote Butte formation 

are regarded as Lower Pennsylvanian, a hiatus of some magnitude is indicated between the two formations. Nearly all the 

localities in the lower part of the formation have yielded a 

new species of Parafusulina. In addition, species of Schwagerina are found at several localities as well as forms tentatively 

referred to as Fusulinella and Triticites. Field evidence shows 

that several of the fusulinid types are either associated or 

QCCUr in almost the same horizon. The fusulines imply that 

the Coyote Butte is not lowest Permian. 

Dr. G. Arthur Cooper is now completing a detailed study 

of the Coyote Butte brachiopods and rePQrts that most of the 

species are of Asiatic affinity; a few are almost exact identities 

witb Russian forms from the Urals and Timan. According 

to Cooper the brachipods indicate Lower Permian. The following identifications were supplied by Cooper: 

Productus cf. P. mammatus Keyserling 

P . . aff. P. porrectus Kutorga 

Avonia tuberculata Schellwieu 

Linoproductus cf. L. sinuata King 

Juresania aff. J. juresanensis Tschernyschew 

lVaagenoconcha n. sp. 

Krotovia pustulata Keyserling 

Koyserlingina sp. 

MMginifera cf. M. involuta Tschernyschew 

Rhyncho-pora n. sp. 

Oamarophoria mutabilis n. var. 

0.. biplicata Stuckenberg 

0. karpinskyi Tschernyschew 

N otothyris nuoleola Kutorga 

N otothyi-is n. sp. 

M artiniopsis sp. 

Spit'iferella n. sp. 

In a recent study of rugose corals from the Coyote Butte 

formation Merriam (1942) has described the following forms: 

Waagenophyllum washbwrni Merriam 

Waagenophyllum ochocoensis Merriam 

Waagenophyllum sp. a. 

Waageno-phyllum sp. b. 

Lithostrotion (Lithostrotionella) occidentalis Merriam 

Lithostrotion (LithostroUonella1) berthiaumi Merriam 

The species of Waagenophyllum support a Permian age and 

point to an Old World relationship of the faunas. 

The ammonoid Eoasianites merriami Miller and Furnish was 

found in the region covered by the present survey, but whether 

it came from the Spotted Ridge Pennsylvanian or the Coyote 

Butte is not known. According to Miller and Furnish * * * it 

appears to be of either Upper Pennsylvanian or Lower Permian 

age. 

SYSTEMATIC DESCRIPTIONS 

Division LYCOPSIDA 

1Lepidodendrid branchlet 

Pia te 36, figure 13 

This small specimen represents the terminal part 

of a slender leafy twig, probably of lepidodendrid affinity. It is 4.5 em long, with a maximum diameter of 

6 mm, measured so as to include the leaves in the foliated part. The lower half or so of the specimen 

bears no appendages or scars of attachment; on the 

upper half, however, there are a number of small (reaching 4 mm in length), closely imbricated leaves, whose 

shape cannot be made out satisfactorily. 

A part of the upper half of the specimen was apparently defoliated before preservation, and in this 

part a few vertically elongated, spirally arranged depressions may be seen faintly (pl. 36, fig. 13,); these 

are strongly suggestive of lepidodendrid leaf cushions. 

Aside from Arnold's observation of a single impression of a stigmarian rootstock in the University of 

Michigan's collection, the specimen discussed here, if 

properly identified, represents the only suggestion of 

the presence of an arborescent lycopodiaceous element 

in the Spotted Ridge flora. 

Division SPHENOPSIDA 

Genus M:ESOCALAKITES Hirmer 

In their monograph of the calamitaleans of western 

Europe, Kidston and Jongmans (1917) recognized that 

certain species of Calamites were characterized by the 

occurrence of directly superposed ribs at some of the 

nodes, in contrast to the more typically alternating ribs 

of most of the species. These forms with superposed ribs were segregated, without nomenclatural 

distinction, into a group referred to as "Section II'1 

(1917, p. 188); it was pointed out that they represent 

a morphologically and chronologically intermediate 

stage between the typical Calamites and the older, supposedly more primitive Asterocalamites, in which all 

the ribs are superposed. 

In a subsequent publication Hirmer (1927, p. 382) 

gave formal recognition to the six species placed in 

IGdston and Jongmans' "Section II'' of Calamites (C. 

roemeri Goeppert, C. cistiiformis Stur, 0,. taitianus 

l(idston and J ongmans, C. haueri Stur, C. rami fer Stur, 

and C. approwimatiformis Stur), erecting the new genus 

M esocalamites for their accommodation. This treatment may prove objectionable to some paleobotanists 

on the grounds that there is insufficient comparative 

know ledge of the foliar and fruiting parts to warrant 

a generic separation of Mesocalamites from Oalamites. 

In supporting Hirmer's adoption of the name Meso-
ADDITIONS TO THE FLORA OF THE SPOTTED RIDGE FORMATION IN CENTRAL OREGON 215 

calamites, however, the present writers feel that this is 

justifiable from the standpoint of convenience in referring to two types of calamarian pith casts that may 

be readily distinguished from each other on the basis 

of nodal organization. It is simpler and less confusing 

to use the descriptive designation M esocalamites than 

the noncommittal term "Section II of Calamites." 

Mesocalamitean pith casts, in most cases not too well 

preserved, constitute a conspicuous element in the U.S. 

Geological Survey's collection of Spotted Ridge plants. 

~lost of these conform closely with Arnold's description 

of Calamites hesperius, but a few specimens clearly indicate that more than 1 and probably 3 species are 

actually present in this assemblage. 

Although M esocalamites is mentioned in Arnold's 

discussion of this species, it is used only as an informal· 

group designation. In conformity with the authors' 

views regarding the desirability of maintaining 

Hirmer's distinction between pith casts of Calamites 

and M esocalamites, the following nomenclatural adjustment is proposed. 

:Mesocalamites hesperius (Arnold) Kamay and. Read, n. comb. 

Pia te 34, figure 3 

Calamites hesperius Arnold, 1958, Palaeontgraphica, Band 93, 

Abt. B, p. 62-63, pl. 24, figs. 1, 6-8. 

Although a few specimens in the U. S. Geological Survey's collection are rather larger than any reported by 

Arnold, most of the specimens present nothing in 

the way of features that might sugge1st a necessity 

for expansion or emendation of Arnold's original diagnosis. A specimen of M esocalamites l.1esperius from 

the U. S. Geological Survey's collection is shown In 

plate 34, figure 3. 

lrlesocalamites crookensis lrlamay and Read, n. sp. 

Plate 34, figures 4, 4a 

This description is based on a single specimen, which 

consists of one side of a flattened internal stem cast. 

Although the specimen is not well preserved, it nonetheless clearly exhibits the more critical features upon 

which the identification of calamitean species is chiefly 

based; that is, the organization of the ribs and nodes. 

The specimen is a straight segment of the stem, 14 em 

long, with a maximum width of 2.0 em. It seems probable that the entire width of the stem is represented, for 

differences in width of the fragment are negligible 

throughout its length. Nine nodes are present, with 

eight complete internodes and an incomplete one at 

either end of the specimen. The internodes are all 

shorter than the width of the specimen, ranging only 

from 1.4 to 1.5 em in length. The specimen shows no 

evidence of branch scars, tubercles, or lea.ves. 

The ribs are essentially straight. They range from 

1.0 mm to more usual widths of 1.5 m1n and are sep379717-56-2 

arated from each other by distinct grooves. The number of ribs on the exposed side of the specimen ranges 

from 10 to 12 on each internode. The nodes are clearly 

defined but lack any distinguishing features other than 

the transverse grooves that mark their positions. The 

overall aspect of this specimen is shown in plate 34, 

figure 4. 

This specimen is interesting chiefly because the ribs 

are preponderantly in direct superposition at the 

nodes, thus providing a close approach to the type of 

nodal organization that distinguishes Asterocalamites 

from the true Calamites. Alternation of the ribs is, in 

fact, evident at only 4 of the 9 nodes present in the 

specimen. In each of these 4, only 3 or 4 of the total 

of 10 or 12 ribs may be seen to alternate with those of 

the next internode. The few ribs that do show alternation have bluntly pointed or rounded ends, while the 

preponderantly nonalternating ribs are distinctly truncated at the nodes. (See pl. 34, fig. 4a.) Some of the 

ribs can be traced through nearly the entire length of 

the specimen without an alteration occurring; 

most of the ribs may, in some part of the specimen, 

be followed over 3 or 4 nodes before finding an alternation. 

Among the six species included by Hirmer in Mesocalamites, M. crookensis may be most closely compared 

to M. approaJ:i!mati/01"'J1'1;is on the basis of the relative 

rarity of alternating ribs common to both of these 

species. However, the regular occurrence of tubercles 

at the ends of the ribs of M. approwimatiformis, and 

their apparently complete absence in M. crookensis in 

itself seems to constitute a sufficient basis for distinguishing the two species ; but aside from this difference 

and that of relative sizes, the holotype of M. arookensis 

compares very closely to the specimen of M. approwimatiformis shown in text figures 79 and 80 of Kidston 

and Jongmans' monograph (1917, p. 205). 

M. crookensis is distinguished from M. hesperius on 

the basis of the broader ( 2.5-3.0 mm) ribs, longer 

(2.3-3.5 em) internodes, the presence of tubercles at the 

apical ends of the ribs, and the apparently higher frequency of alternating ribs in M. hesperius. Arnold 

makes no mention of the relative frequencies of alternating and superposed ribs, but his photographs of the 

holotype of M. hesperius (1953, pl. 24, figs.l, 6, 7, and 8) 

show a much more nearly equal distribution of the two 

than present in M. arookensis. 

Insofar as they are presently known on the basis of 

the limited amount of material at hand, the features 

of M esocalamites arookensis are summarized below. 

Specific diagnosis.-Internal casts at least 2 em in 

diameter; internodes reaching 1.5 em in length, consistently wider than long, and differing little in length 

in the same specimen. Ribs straight, lacking tubercles, 1.0-1.5 mm wide, and separated by distinct 
.216 CONTRIBUTIONS TO GENERAL GEOLOGY 

grooves. Ribs preponderantly superposed, usually 

continuous over several nodes; alternating ribs with 

bluntly pointed apices, superposed ribs truncated. 

Branch scars not known. 

H olotype.-USN!f 40708. 

Mesocalamites sp. indet. 

Pia te 34, figures 1, 1a, 2 

The presence of still a third mesocalamitean species 

in this flora is indicated by a few specimens which, although too fragmentary for positive specific determination, display some features that strongly oppose their 

identification with either JJ. hesperirl.ts or lJl. crookensis. 

The largest specimen, shown in plate 34, figure 2, is 

a fragment of the flattened impression of a stem, 13 em 

lono- · the widest part of the specimen measures 1.7 em, b' 

but it is not clear whether this represents the entire 

·width of the specin1en or not. 

Only two nodes are preserved ; the intervening internode is quite long, 1neasuring 5.8 em. The ribs are 

straight and very narrow in proportion to their length, 

in no instance exceeding 1.0 mm (and most typieally 

frmn 0.5-0.7 mm) in width. The nodal relations 

of the ribs cannot be made ont in this specimen. 

The fragmentary speeimen shown in plate 34, figures 

1 and 1a, is 4.8 em long and contains only 1 node (the 

2 nearly transverse lines, 1 near each end of the 

speeimen, are not nodes, but fractures in the matrix) ; 

the internodes were thus at least 2.8 em long, measured 

from the single node to the farthest end of the specimen. 

As in the specimen deseribed in the preeeding paragraphs, the ribs of this one are proportionately narrow, 

measuring no more than 0.6-0.8 mm in width, and 

chiefly on this basis it is assumed that both speein1ens 

represent the same species. 

Although it is only a small fragment, this speei1nen 

dearly exhibits nodal superposition of its ribs, which 

limits the possibilities of its generic identity to Jf esocalmnites. As shown in plate 34, figure 1a, all the ribs 

are in direet superposition, and some of them converge 

toward a common point on the nodal line, as frequently 

occurs in the im1nediate area of calamitean branch 

scars. In this instance, however, there is no clear evidence of a branch scar, unless the shallow depression 

present at the point of convergence of the ribs 1nay be 

interpreted as such. 

Even though their superposed ribs indicate a relationship of these specimens to both lJJ esocalamites hesperius 

and 11/. crookensis, they appear to represent a different 

species by virtue of the great length of the internodes 

and the proportionately s1nall width of the ribs. On 

the other hand, they show some resmnblances to both 

Jf. rramifer (Stur) Hirmer, as illustrated by Kidston 

and Jongmans (1917, pl. 141, fig. 4), and lJJ. cistiiforrnis 

(Stur) Hirmer (compare with I~iclston and Jongmans, 

1917, pl. 142, fig. 2, and pl. 147, fig. 1), but n1ore satisfactory specimens are necessary before either of these 

two species can be positively identified in the Spotted 

Ridge flora. 

Genus PHYLLOTHECA Brongniart 

Although more than 2 dozen species of Phylloth.eca 

have been previously reported from different parts of 

the world, to the best of the writers' knowledge, the 

Mills' Ranch locality is the only source of this genus 

known in the United States at present. 

Phyllotheca aetually constitutes a problematical and 

poorly understood genus, in spite of the frequency with 

,vhich it has been reeorded in the literature. According to Seward's ( 1898, p. 281-283) discussion of this 

genus, it ean be distinguished from the related calamarian genus A nnruiaria only on the basis of relative 

development of the leaves of one whorl and the attitude 

of the whorls; in Phyllotheca the basally fused leaves 

of any one whorl are all the same size and spread equally 

in all directions from the supporting axis, but those 

of Annularia are unequally developed and tend to lie 

in one plane. 

On the basis of this distinction the Oregon material 

is referable to Phyllotheca; 1 it is described below in 

detail because of the unusual nature of some specimens 

that illustrate the actual organic continuity between 

stems, leaves, and frnctifieations. Such a continuity 

\Vas apparently not demonstrable in the University 

of 1\iichigan's collection, for which reason Arnold made 

no definite specific determination. 

Phyllotheca pa ulinensis :M:amay and ltead, n. sp. 

Plate 34, figures 6-8, plate 35, figures 1-6 

PhJJllothcca sp. ( cf. P. rallii Zeiller), Arnold, 1953, Palaeontographica, Band 93, Abt. B, p. _63, pl. 24, fig. 2-5, 1953. 

'Vith the exeeption of the fern Pecopterris oregonensi8 

Arnold, Phyllotheca paulinensis appears to have been 

the most ubiquitous element of the Spotted Ridge flora, 

judging from the large nmnber of fragments in the 

U. S. Geological Survey's collection. Most of these 

consist of isolated leaves or parts of leaf whorls. 

Detached cones are abundant, and there are also a few 

fairly large stem fragments, some with lateral branches 

and fruetifications attached. 

The general attitude of the leaves is shown in plate 

34, figures 6 and 7, where they can be seen arising from 

1 The phyllothecoid affinity of the Turkish species Phyllotheca mllii 

Zeiller, which the Oregon material very closely resembles, wag. quet;-

tioned by Gothan (1927, p. 150), primarily on the basis of the organization of the cones of P. rallii. As the result of a res,tudy, as yet unpublished, of the Carboniferous floras of Turkey, Jongmans has recently 

shared Gothan's views ; he has "expressed the opinion that P. rallii is a 

peculiar form of Annularia, probably related to A. radiata (oral communication delivered before the Eighth International Botanical Congress, Paris, 1954). The present writers, however, prefer to tentatively 

consider both P. mllii and the Oregon material as truly phyllothecoid, 

in the absence of clearly demonstrable unequal formation of leaves or 

foliar mosaics. 
ADDITIONS TO THE FLORA OF THE SPOTTED RIDGE FORMATION IN CENTRAL OREGON 217 

the stem fragments at several of the nodes. The leaves 

generally stand out from the stem at a nearly perpendicular angle, with their tips gently bending upward 

to describe a shallow saucerlikewhorl. 

The. leaves range in length frmn 5 mm on the smaller 

branchlets (pl. 34, fig. 6) to 1.5 em on the larger axes 

(pl. 34, figs. 7, 8; pl. 35, figs. 3, 4). All the leaves of 

any given whorl, however, appear to be equally developed. Their basal widths range from about 

0.75 mm to 1.5 mm, but this does not seem to be consistently proportional to length, for the shorter leaves 

are usually relatively broader than the longer ones. 

The leaves are consistently widest at their bases and 

taper gently toward their tips, without any abrupt 

narrowing of the lamina. 

The basal fusion of the leaves into the collarlike 

structure that constitutes one of the distinguishing 

features of Phyllotheca is difficult to demonstrate because, in instances where the leaf whorls are attached 

to a stem fragment, the presence of the stmn itself obscures this feature. However, in a few whorls that were 

compressed in the plane of the node that bore them, 

the fusion can be seen between 3 or 4 members of a 

whorl (pl. 34, fig. 8, and pl. 35, fig. 3). The fusion is 

restricted to the very basalmost parts of the leaves and 

results in an extremely narrow collar that could easily 

be overlooked; the collar has not been observed to exceed 1.5 mm in width. 

Although none of the specimens include a complete 

foliar whorl compressed in such a way that would facilitate the determination of the exact number of leaves 

in a whorl, one nearly complete whorl (pl. 35, fig. 4) 

contains parts of 20 leaves, and less complete ones contain from 12 to 18. It thus seems likely that 2 dozen 

or more leaves constitute the full foliar complement 

of a node. The venation of the leaves is not preserved. 

J\1:ost of the nu1nerous cones are detached specimens, 

but a few were preserved in organic connection with 

leafy stem fragments, so that there exists no doubt concerning the relationship of these parts. 

The cones differ considerably in size; some are only 

2.5 em or so in length (pl. 35, fig. 2), but others reach 

lengths of 7 em (pl. 35, fig. 6). The largest specimens 

are inc0mplete, suggesting that total lengths of considerably more than 7 em may have been attained. The 

smallest specimens are only 6 or 7 mm wide, Ineasured 

bebveen the tips of the extended sterile appendages, 

while one incomplete specimen (pl. 35, fig. 5) is nearly 

2 em wide. The average width, however, is about 1 em. 

The sterile appendages (bracts) are clearly sho\vn 

by every cone specimen, but determining the number 

of bracts to a whorl has not been possible. In the 

lnrger specimens the whorls of bracts are usually spaced 

about 2 min apart, and the free parts extending beyond the sporangia reach 4mm in length (pl. 35, fig. 6). 

They usually stand out from the cone axis at nearly a 

right angle, with their tips gently bent upward toward 

the apex of the cone. 

None of the critical dPtails of the sporangia were observed; and it was impossible to isolate spores by chemical maceration, although several attempts \Vere made 

with the more promising specimens. The fertile parts 

of the cones merely appear as dark masses interposed 

between the whorls of bracts (pl. 35, figs. 1, 5, and 6) ; 

in some places these masses show•ronncled outlines or 

a series of rounded depressions or protuberances that 

indicate the original positions of the sporangia. In 

this connection, see the specimens sho,vn in plate 34, figure 5. Each specimen consists of a circularly arranged 

group of small rounded bodies less than 0.5 mm in 

diameter. In the better specimen, shown at the bottom 

of the photograph, there appear to be 8 or 9 of these 

objects, which may represent sporangia; opposite each 

there is a faint line which probably indicates the presence of an accessory organ, perhaps a subtending bract. 

These two specimens quite possibly represent vd10rls 

of Phyllotheca sporangia that were compressed transversely to the axes of the cones that produced them, 

exposing the sporangia in such a way that the individuals may be made out fairly well. If so, however, these 

must have been produced by very small cones, for the 

circlets each measure only 2 mm or so in diameter, 

which is significantly smaller than the width of the 

smallest cone specimens present in the collection. There 

is also the further possibility that these represent the 

fructification of still another genus of articulates. 

The attachment of cones to vegetative parts is clearly 

illustrated in plate 35, figure 1. Here the terminal part 

of a slender branch fragment is shown, with parts of 

four eones attached. The largest of these is 5.5 em 

long in its incomplete condition and appears to represent a direct continuation of the tip of the vegetative 

axis ; fron1 the base of this cone arises a second, rather 

smaller one. The two nodes below these cones are apparently sterile, since only the ordinary foliar leaves are 

seen here. Each of the next two lower nodes, however, 

is fertile, one cone arising from each. In all cases 

where lateral cones have been seen, they are sessile, 

arising directly from the axil of a foliar whorl. 

The large specimen shown in plate 35, figure 2, is of 

interest in that it bears at least one slender lateral 

branch, to which three small cones are attached; this 

branch is seen arising from the left side, at about the 

middle of the specimen. A short distance below this 

branch is another, also fertile; although the actual 

organic connection of this branch to the main axis cannot be seen, their relative positions strongly suggest an 

original organic connection. At some places on the 

specimen, ordinary foliage arises from the nodes. The 

attachment of sterile foliage to the stem, however, may 
218 CONTRIBUTIONS TO GENERAL GEOLOGY 

be seen still more clearly in the specimen shown in 

plate 34, figure 6. This specimen is 17 em long and 

contains 21 nodes, from several of which arise small 

sterile lateral branches; the remainder of the nodes 

show p3rts of ordinary foliar whorls. 

The largest stem fragment, shown in plate 35, figure 2, 

lacks part of its width through nearly half of its total 

length of approximately 24 em, but at either end the 

specimen appears to ·be nearly complete. Its width 

ranges from 2 to 3 em, but this may be due to relative 

degrees of compaction at different parts of the specimen. The internodes average about 1.5 em in length 

and are thus consistently wider than long. Details of 

the ribbing and nodal organization are not clear. At 

the upper part of plate 35, figure 2, the ribs appear 

very narrow, but at the bottom of the same illustration 

they are appreciably wider; they seem to alternate at 

some of the nodes and continue uninterruptedly over 

others. The stems of Phyllotheca paulilnensis thus 

display nodal features of Hirmer's M esocalamites, but 

in the absence of information regarding the relative frequencies of alternating and superposed ribs, there is no 

clear basis for a comparison to the pith casts referred to 

M esocalamites earlier in this paper. 

The proposal of the new specific name Phyllotheca 

paulinensis for the Oregon material is based largely 

on comparisons with the three previously described species that are known in the fertile condition: P. deliquescens Schmalhausen (1879), P. uluguruana Gothan 

(1927), and P. rallii Zeiller (1899). The fructifications of P. deliquescens and P. 1.tluguruana closely resemble each other in the presence of elongated fertile 

zones between the sterile whorls of bracts, to which 

large numbers of fertile units were attached at random. 

In this feature these species stand apart from P. rallii 

and P. paUlinensis, in which the arrangmnent of both 

sterile and fertile whorls is much more compact, each 

internode producing only one whorl of fertile units. 

Although the cones of P. rallii and P. paulinensis thus 

show a typically calamostachyan organization in this 

respect, the reference of these species to Phyllotheca 

seems preferable on the basis of leaf characters, which 

are typically neither annularian nor asterophyllitean. 

P. paulinesis is extremely similar toP. rallii. However, the two species are distinguishable from each 

other on the basis of the following points of contrast : 

Internodes of P. paulinensis do not exceed 2 em in 

length and are consistently wider than long, but .those 

of P. rallii are from 4 to 8 em long and always longer 

than wide; cones of P. paulinensis reach 7 em or more 

in length, but those of P. rallii reach a maximum length 

of 4 em; cones of P. paulinensis are borne sessile in 

the axils of foliar whorls, but those of P. rallii are 

pedicellate. 

The known characters of Phyllotheca pauUnensis 

are summarized below. 

. Specific diagnosis.-Largest known stem fragments 

to 3 em in width; internodes averaging 1.5 em in 

length, consistently wider than long; ribs apparently 

alternating or directly superposed at the nodes. Leaves 

produced as many as 20 or more in a whorl; leaves 0.5-

1.5 em long, basally 0.75-1.5 mm wide, tapering gently 

toward their tips; basally fused parts of leaf whorls 

producing a narrow sheath, usually not more than 1.5 

mm wide. Cones 2.5-7 em or more inlength, 6 mm to 

nearly 2 em wide, measured between tips of bracts; 

bracts extending to 4 mm beyond fertile units, produced in whorls usually 2 mm apart; sterile whorls 

apparently separated by single whorls of fertile units, 

but mode of attachment of sporangia and nature of 

spores unknown; cones produced terminally on side 

branches or laterally, the lateral ones borne sessile in 

the axils of foliar whorls. 

Syntypes.-USNM 40710-40718. 

Genus ASTEROPHYLLITES Brongniart 

Ct. A. equisetiformis (Schlotheim) Brongniart 

Pia te 36, figures 11 and 12 

The surfaces of several slabs in the U. S. Geological 

Survey's collection are covered with numerous specimens of this delicate foliage; the best of this material , 

is shown in plate 36, figure 12. 

Most specimens consist of detached parts of foliar 

whorls; however, one very unsatisfactorily preserved 

specimen, not illustrated here, shows the attachment of leaves to the axis. The specimen contains 6 

internodes, each about 1 em long and 8 mm wide; each 

node bears a few leaves, but it is not possible to deter .. 

mine the full number of leaves produced by a node. 

The ribbing and nodal organization of this specimen 

are obscure. 

The leaves range from 4 to 12 mm in length. They 

are very narrow, scarcely exceeding 0.5 mm in width 

in the larger specimens. The leaves taper gently, terminating in sharp points; the acicular appearance of 

the leaves is shown best in plate 36, figure 11, which 

shows the tip of a small branchlet, thickly clothed with 

small, immature leaves. 

Because of its imperfect preservation (and particularly in the absence of branching foliated axes that 

would demonstrate what differences exist between the 

leaves produced by the different orders of branches), 

this material cannot with any degree of confidence be 

specifically determined. There is little doubt, however, that its reference to the genus Asterophyllites 

is correct. The specimens are somewhat reminiscent 

of some of the smaller leaved examples of Asterophyllites equisetiformis, which is perhaps the most common 

species of this genus. 
ADDITIONS TO THE FLORA OF THE SPOTTED RIDGE FORMATION IN CENTRAL OREGON 219 

Division PTEROPSIDA 

Genus PECOPTERIS Brongniart 

Pecopteris oregonensis Arnold 

Plate 36, figures 1-7 

This species comprises perhaps 75 percent of the plant 

material in the U. S. Geological Survey's collection and 

is briefly mentioned here for the purpose of clarifying 

one point in Read and Merriam's preliminary report of 

1940. They tentatively listed "several species of Sphenopteris" and "Daetylotheca" as components of the flora 

(1940, p. 109). Arnold, however, has treated the 

sphenopteroid foliar elements as variants of the more 

typically pecopterid pinnules of Pecopteris oregonensis, 

and the "Dactylotheca" as the fructification of that species. Careful reinspection of the U.S. Geological Survey's collection has revealed no basis for variance with 

.... L\.rnold's treatment of these elements. It is thus apparent that truly sphenopterid leaves are absent :from 

the Oregon flora, and all the fernlike :foliage with its 

abundant fructifications almost certainly belongs to the 

single species Pecopteris oregonensis. Several specimens of this species are illustrated in plate 36, figures 1-7. 

Arnold's description of this species may be amplified 

by the U. S. Geological Survey's collection with regard 

to one minor point. Arnold described the aphlebiae 

of P. oregonensis as being "only one centimeter or more 

long." Several specimens in the U.S. Geological Survey's collection, however, illustrate that these appendages were sometimes larger, more conspicuous structures. While many of the specimens do :fall within the 

size range given by Arnold, they are typically well over 

2 em in length (pl. 36, fig. 6) , and 1 incomplete specimen, shown in plate 36, figure 5, measures 3.3 em to its 

broken tip. If it had been complete, this particular 

aphl~bia would probably have been more than 4 em long. 

In this respect, the aphlebiae of P. oregonensis compare 

much more closely with those of Dactylotheca plwmosa, 

as illustrated by Kidston (1924, pt. 5, pl. 93, figs. 2 

and 3). 

Genus DICRANOPHYLLUM Grand'Eury 

This genus, still of problematical affinities, now contains at least 24 species, with occurrences having been 

reported in Asia, western Europe, Great Britain, Australia, and North America. Dicranophyllum is :found 

chiefly in strata of Pennsylvanian or Permian age, although Dawson ( 1881) reported one species (D. australicum Dawson) from the Devonian of Australia. 

There is considerable doubt that the reference to Dicranophyllwm is correct in the latter instance. 

Dicranophyllum is rare in North American rocks. 

Before Read and Merriam's announcement of its presence in the Oregon flora, only six other occurrences had 

been recorded. These were D. dichotomwm Lesquereux 

( 1880, p. 553), D. dimorphum Lesquereux ( 1880, 

p. 554), D. glabrum (Dawson) Stopes (1914, p. 79; Bell, 

1940, p. 132), D.f garnettensis Elias (1936, p. 12), and 

some questionable specimens doubtfully referred to 

Dicranophyllu1n by White (1899, p. 272). 

Dicranophyllum rigidum Kamay and Read, n. sp. 

Plate 37, figures 3-lOa 

This species is represented in the U. S. Geological 

Survey's collection by a fairly large number of specimens, including several large fragments of stout 

branches, apparently with most of their leaves preserved intact. Most of the material, however, consists of detached leaves and small stem :fragments, some 

partly denuded of their leaves before preservation. 

None of the specimens demonstrate the fruiting habit 

of this plant. 

The branch fragments range up to about 1 em in 

diameter, but most of the specimens are more 

slender than this, usually measuring only 2-5 mm in 

thickness. In only one specimen has branching been 

observed; however, the type of branching (sympodial 

or monopodia!) cannot be determined from this specimen. 

Details of the leaf cushions are not well preserved 

in this material ; in only one specimen, sho:wn in plate 

37, figure 4, can they be seen at all. The exposed surface of this branch fragment appears to have been completely decorticated before preservation and shows 

only a faint pattern of shallow leaf cushion impressions 

that give the specimen a superficially lepidodendroid 

aspect through their vertical elongation and spiral disposition. As shown in this figure, the phyllotaxy is a 

fairly close spiral. 

The leaves were apparently persistent, for the decorticated stem fragment shown in plate 37, figure 4, 

is the only specimen in the collection in which the 

leaves are not attached. The leaf bases are decurrent ' a feature that is best seen in the smaller branches, where 

the leaves are not very densely arranged. Decurrence 

of the leaves is illustrated in plate 37, figures 3, 9, 10, 

and lOa. 

The leaves differ considerably in length, ranging 

from about 1.5 to 4.5 or 5 em long, and the stoutest 

specimens are about 1.5 mm wide at the base. Some examples of the longer leaves may be seen in plate 37, 

figure 6. The branch· :fragment toward the right of 

this figure is densely covered with leaves, which makes 

it difficult to follow any individual leaf :from its tip 

to the point of its attachment to the axis. However, 

it is quite evident that some of the leaves approach 

5 em in length. In contrast to these, the leaves shown 
CONTRIBUTIONS TO GENERAL GEOLOGY 

in plate 37, figures 10 and lOa, are not only much more 

loosely arranged on the axis but are also much shorter, 

measuring only 1.5 em or so in length. 

The specimen shown in plate 37, figure 9, is of interest because it represents the apex of a branch, preserved before complete elongation of the axis and extension of the leaves. This fragment is 4 em long, 

and its apical half is so densely covered with leaves 

that it is difficult to distinguish the individual leaves 

from each other. The identity of this specimen as 

Dicranophyllum is nevertheless established by the 

forked tips clearly visible in some of the leaves. These 

leaves average about 2 em in length, and their straightness gives the impression that they must have been 

fairly rigid in life, perhaps as much so as the needles 

of a spruce or fir. The same impression is lent by most 

of the other leaves in the collection, including the longer 

speCimens. 

The chief distinguishing characteristic of D·icranophyllum (repeated bifurcation of the leaves) is well 

illustrated in plate 37, figures 7, 7a, 8, and Sa. The 

smaller leaves bifurcate twice, resulting in four essentially equal divisions at their tips. This point, however is not clearly demonstrable in the longest leaves, 

for it is difficult to trace the entire length of one leaf 

in the longest specimens. These bifurcate at least 

twice; in consideration of their greater length, however, it is quite possible that they were more divided 

than the smaller leaves. 

Isolated leaves, each with a double bifurcation, are 

shown in plate 37, figures 7 and 8. The specimen shown 

in figure 8 probably represents part of one of the longer 

leaves; this fragment is 15 min long, and each of the 

4 ultimate segments is about 5 mm long. In the latter 

feature this specimen differs frmn that shown in plate 

37, figure 7, for there the ultimate divisions are considerably shorter (less than 2 min long) , and n1ore 

spinelike. Despite such differences as this, however, 

all the complete leaf specimens in the collection appear 

to be consistent in the following features : The two 

foliar segments resulting from each bifurcation always 

include a fairly narrow angle (usually between 30° 

and 40°), and each bifurcation of the lamina occurs 

above the middle of the foliar segment involved. 

Det~ils of the venation are difficult to determine because of faulty preservation. Some of the leaves contain coalified median streaks that give the impression 

of broad midveins when viewed with the naked eye. 

(See pl. 37, fig. 7.) These streaks may be as much 

as half the width of the lamina; they divide in accordance with the foliar divisions and proceed almost to 

the tips of the leaves. If these are vascular strands, 

there is no evidence that more than one was present 

in each laminar division. 

Although several of the previously recorded species 

of Dicranophyllum are too incompletely known for a 

satisfactory comparison to the Oregon material, the 

latter can be distinguished from most species primarily 

on the basis of leaf size, even though other points of 

contrast also exist. SeYeral species have leaves tl)at 

are considerably larger than those of D. rigidun~ j in 

this respect, the greatest contrast is shown by D. striatum Grand'Eury (1877) and D. latifoliWJ~~ Sterzel 

(1907), leaves of which have been reported to exceed 

20 em in length. In the opposite extreme, we find the 

2 species D. domini Nemejc (1929) and D.? brevifoliurm 

l{awasaki (1931), whose relatively small dimensions 

preclude a conspecific identification with D. 1·igidum; 

neither of these 2 species produced leaves longer than 

17mm. 

With regard to leaf size, D. rigiduuL may perhaps be 

most closely compared to D. gallicum Grand'Eury 

(1877), the most completely understood representative 

of this genus. Although the leaves of these two species 

correspond rather closely in size, they differ in manner 

of foliar division, those of D'. rigidunL displaying a consistently more symmetrical pattern of bifurcation than 

those of D. gallicun'b. 

Dicranophyllu1n rigidwn is so named with reference 

to the generally rigid aspect of the leaves, and is diagnosed below. 

Specific Diagnosis.-Foliage apparently persistent, 

rigid, arranged in closely crowded spiral phyllotaxy, 

and seated upon slightly elevated vertically elongated 

leaf cushions. Leaves 1.5-5.0 em long, not more than 

2111111 wide at their bases. Shorter leaves bifurcating 

only twice; the resultant four ultimate divisions sharply 

pointed, 2 mm or less in length ; longest leaves possibly 

bifurcated more than twice, with ultimate segments 

reaching 5 or 6 mm in length. All bifurcations essentially symmetrical and occurring beyond the middle of 

the dividing segment; 1nembers of each division including an angle of approximately 30°-40°. Vascularization of leaves apparently consisting of a single median 

vein, bifurcating according to laminar divisions. Reproductive organs unknown. 

Syntypes.-USNM 40733-40740. 

It should be pointed out here that in view of the 

range of leaf size, some authors may prefer the treatment of the two extren1es as distinct species, but such 

a distinction cannot, in the writers' opinions, be clearly 

demonstrated with the present Inaterial. The fact that 

several examples of leaves of intermediate length are 

present in the collectioi1 suggests, rather, that a single 

variable species is represented, possibly complicated by 

genetic polymorphism or by eeologically stimulated 

variation of the foliage. 
ADDITIONS TO THE FLORA OF THE SPOTTED RIDGE FORMATION IN CENTRAL OREGON 221 

PROBLEMATICA 

?Cordaianthus Grand'Eury (cf. C. longibracteatus Florin) 

Plate 36, figure 10 

This tentative determination is offered on the basis 

of the single specimen illustrated in plate 36, figure 10, 

which appears to represent the top part of a poorly 

preserved cordaitean inflorescence. The axis of the 

fragment presents a rather slender appearance, being 

5.5 em long and only 2.5 mm wide at its base. It bears 

about a dozen alternately arranged bractlike appendages, which arise from the axis at intervals of 7-11 mm. 

The bracts depart at wide angles and assume gently 

ascending positions. The largest bract, apparently 

complete, is 2.8 em long; the most, however, are incomplete, consisting of only the basal parts. 

A small budlike structure, 3-4 mm long, 1nay be 

faintly se.en in the axil of nearly every bract. The 

preservation of these structures is especially poor; but 

although their organizational details are completely obscured and no actual fruiting organs are preserved, they 

are sufficiently consistent in relationships of their size 

and position with the subtending bracts that they can 

scarcely be considered to be the results of accidental 

preservation. Even in the absence of any knowledge of 

the critical details, the gross appearance of this specimen is strongly reminiscent of a Oordaianthus inflorescence, with its sterile bracts and axillary dwarf 

shoots. 

A tentative comparison to Oo1•daianthus longibracteatus Florin is suggested here, on the basis of the long 

bracts present in this specimen. In certain other features, such as its more slender main axis and less 

crowded appendages, the Oregon specimen presents a 

somewhat. less robust, more lax aspect than that of 

0. longibracteatus ( cf. pl. 36, fig. 10, with Florin, 1950, 

pl. 1, fig. 1) ; these contrasting features suggest that the 

Oregon specimen might actually be determinable as a 

new species of Oordaianthus, were it more satisfactorily 

preserved. 

Cf. Schizopteris trichomanoides Goeppert 

Plate 36, figures 8-9 

The specimens illustrated in plate 36, figures 8 and 

9, are mentioned here because of a notable similarity to 

a specimen figured by Zeiller ( 1892, pl. 1, fig. 8) under 

the binomial Schizopteris trichmnanoides and apparently accepted by him as the remains of a genuine fern. 

The Oregon material consists of several fragments of 

a repeatedly bifurcated structure that are preserved as 

. a clark stain on the surface of the rock, with only here 

and there a thin fleck of carbonaceous residue to suggest 

a truly vegetable origin. The largest fragment (pl. 36, 

fig. 9) is a fan-shaped structure with a dozen or 1nore 

ultimate divisions, which are the result of regular hifurcation at intervals of 3-7 mm. The individual segments are narrow and straplike, not exceeding 2 mm in 

width, and essentially equal in dimensions to their 

counterparts resulting from the bifurcations. (See pl. 

36, fig. 8.) In some parts of the specimens there 

are indications of a narrow clark band traversing the 

middle of the segments, suggesting a median nerve or 

some other type of mechanical thickening in the original 

organism. There is no indication of attachment to 

an axis, for the basal parts of the fragments are not 

present. 

Numerous examples of similarly bifurcated structures have been recorded in paleo}Jotanicalliterature, 

as, for example, Schizopteris dichotoma Gumbel (see 

Zeiller, 1892, pl. 1, fig. 7) or M archantites. erectus 

(Leckenby) Seward (Seward, 1898, fig. 49). However, 

the comparison made here is suggested because the overall appearance of the Oregon material seems to resemble 

most closely Zeiller's figure of Schizopteris trichomanoides. 

The question of natural affinities of such fossils is 

difficult. They have been variously interpreted as 

lichens, ·liverworts, algae, and ferns, but in many instances, as in the present one, there has been little more 

than the gross outline of the plant preserved as a basis 

for its systematic interpretation. 

Roots of unknown affinity 

Plate 37, figures 1-2 

These structures are briefly brought to attention here 

because they constitute a conspicuous element among 

the other plant fragments in the Spotted Ridge flora 

and because certain features of appearance could pos-· 

sibly lead to misinterpretation and the unwarranted 

assumption of a nonexistent element in the flora. 

The collection contains numerous fragments of long, 

straplike organs measuring from 2 mm to 2 em or more 

in width. (See pl. 37, fig. 2.) The longest fragments 

reach 7 em in length; these show little difference· in 

width throughout their length. They are p:reserved 

as very thin carbonaceous films, and one of their more 

conspicuous features is the finely striated nature, of 

their surface, best shown in plate 37, figure 1. The 

striations are very closely spaced and run parallel to 

the length of the fragments. In most instances the 

edges of the specimens are smooth and unbroken; their 

overall appearance at first gives the impression that 

we are dealing with a group of poorly preserved small 

to medium parallel-veined leaves, perhaps of cordaitean 

affinity . 

Other features, however, establish these specimens 

as roots rather than leaves. Each specimen contains 

a single thick, usually centrally located strand, which 

is without doubt the vascular system of the root. This 
222 CONTRIBUTIONS TO GENERAL GEOLOGY 

structure is clearly shown in plate 37, figure 1. The 

absence of any considerable substance to the specimens 

suggests that compaction of the specimens was preceded by nearly complete decay of the cortical tissues, 

with the result that the vascular system is clearly seen 

and is only slightly obscured by the remains of the 

dermal layer, represented by the parallel striations. 

In some specimens the central strand crosses diagonally from one side of the root to the other, while the 

fine striations of the dermal layer uninterruptedly follow their courses parallel to the length of the root. 

Such a displacement in position of the vascular strand 

would not be unusual if, by decay of the surrounding 

cortical tissues, the strand were deprived of organic 

connection with the dermal layers. 

The specimen shown in plate 37, figure 1, is of further interest in that it illustrates the departure of a 

lateral rootlet from the right side of the specimen; the 

vascular strand of the lateral rootlet may be seen originating from the central strand of the parent root. The 

surface of this specimen also contains several circular 

punctations that are interpreted as scars of attachment 

of rootlets. 

Although the rootlike nature of these specimens is 

quite obvious, it is not possible to correlate them with 

any of the foliar species already described. 

DISCUSSION 

The composition of the Spotted Ridge flora now may 

be systematically summarized as follows: 

Lycopsida 

?Lepidodendroid branchlet 

Stigmarian rootstock 

Sphenopsida 

Asterophyllites sp. ( cf. A. equisetiformis) 

Mesocalamites hesperius 

M esooalamites crookensis 

M esocalamUes sp. indet. 

Phyllotheca paulinensis 

pteropsida 

Pecopteris oregonensis 

fCordaia;nthus ( cf. 0. longibracteatus) 

Dicranophyllwm rigidum 

P:roblematica 

Of. Bchizopteris trichomanoides 

Undetermined roots 

It again should be emphasized here that the flora is 

strongly dominated by four of the above-named elements (Mesocalamites hesperius, Phyllotheca paulinetnsis, Pecopteris oregonensis, and Dicranophyllum 

rigidwm) ; all the other entities are represented in the 

collection by single or, at the most, a very few specimens. It is our opinion that this floristic picture is 

not an artificial one that has been distorted by insufficiently thorough collecting, for the U. S. Geological 

Survey's collection is a large one, extremely rich in 

plant fragments. The Spotted Ridge flora is, then, of 

primary interest from the point of view of its relatively 

few recognizable species as compared with the highly 

diversified plant assemblages that are more usually 

characteristic of the Pennsylvanian period. The pteridosperms and sphenophylls are completely lacking; 

the lycopods and cordaitaleans are only weakly represented by a few questionable specimens_ and a single 

species represents the ferns. 

The small number of species present in the flora 

stimulates even further interest when one compares the 

dominant forms with other Carboniferous florasAmerican or European-for the purpose of deriving 

conclusions regarding the geologic age of the Spotted 

Ridge formation. It soon becomes apparent that, 

apart from the limited composition of this assemblage, 

it is further unique because its dominant elements 

cannot be compared to any American flora of wellestablished stratigraphic position. The prehlem of the 

geologic age of this flora is, therefore, much more complex than it first appears and demands a reconsideration of the few identifiable species contained in the 

assemblage. 

Read and Merriam (1940) expressed the opinion that 

this flora is of early Pennsylvanian age; at the same 

time, however, they allowed the possibility of a late 

Pennsylvanian age designation. This opinion was 

based in part on negative evidence; that is, the apparent absence from the flora of certain genera diagnostic of strata of late Pennsylvanian age. Arnold 

(1953, p. 67) also stated the opinion that the flora 

most likely represents early Pennsylvanian time. 

A consideration of the geologic occurrences of those 

species which can be most favorably compared with 

the Spotted Ridge flora reveals a conflicting· and rather 

puzzling set of circumstances, described below. 

1. lllesocalamites is a· genus that appears to be restricted to strata of Pottsville or pre-Pottsville age. 

I\::idston and Jongmans (1917, p. 188) point out that 

with the exception of M. rom.eri, which is known to 

occur in the basal part of the European Lower Carboniferous, the species belonging to this group are 

characteristic of the upermost part of the Lower Carboniferous (equivalent to the American Mississippian). 

To this may be added the evidence of known North 

American occurrences, cited by Arnold ( 1953, p. 

62-63) ; },f esocalamites has been reported from the 

Pottsville of Pennsylvania and West Virginia, the 

Canso group (lower Pennsylvanian) of Nova Scotia, 

and the Namurian of Greenland. On the basis of similarities of M. hesperius and 111. crookensis to previously 

described members of this genus, then, one might readily assume a lower Pennsylvanian or even upper ~ississippian age for the Spotted Ridge formation, especially if the associated floristic elements were not known. 
ADDITIONS TO THE FLORA OF THE SPOTTED RIDGE FORMATION IN CENTRAL OREGON 223 

2. Insofar as it is presently understood, primarily 

on the basis of detached foliage or defoliated stem fragments, the genus Phyllotheca has predominantly Permian or early Mesozoic stratigraphic distribution. P. 

paulinensis, however, most closely resembles P. rallii, 

a species that is known only from the Westphalian A 

of Turkey. Thus, the evidence of Phyllotheca paUlinensis appears to support an early Pennsylvania age assignment for the Spotted Ridge formation. 

3. Pecopteris oregonensis is perhaps the most enigmatic element in the flora, from the standpoint of 

stratigraphic significance. Although it combines features reminiscent of several European species, its overall aspect is suggestive of a closer relationship to Pecopteris pl!urmosa (Kidston's Dactylotheca pl!wmosa) 

than to any other species. This would seem to suggest 

Pottsville age, according to present information on 

North American floras; White ( 1900, p. 884) has reported this species from the Sewanee coal of Tennessee, 

and Bell (1944, p. 84) has reported it as a common 

element in the Cumberland group (lower Pennsylvanian) of Nova Scotia. In Great Britain, where this 

species is much better understood, however, it is known 

to range throughout the entire upper 0arboniferous; 

and, according to Kidston ( 1924, p. 391), "In the Radstock Series it occurs as a common and characteristic 

plant." It thus appears that little confidence may be 

placed in Pecopteris oregonensis as an age indicator. 

4. The presence of Dicranophyllwm injects an element of decidedly late Pennsylvanian affinity into the 

Spotted Ridge flora. In the absence of satisfactory 

North American records of this genus, this again is 

largely based on the known stratigraphic occurrences 

of European species. In Europe Dicranophyllwm is 

well known from many localities, and although several 

species have been reported from Permian strata, 

Seward ( 1919, p. 93) has pointed out that it is more 

characteristically a Stephanian (upper Pennsylvanian) 

genus. Read and Merriam (1940, p. 111) suggest that 

the presence of Dicranophyllwn in the Oregon flora 

may be interpreted as indicating a mesic upland facies 

instead of younger age. Although such a possibility 

should not be denied, the great preponderance of the 

fern Pecopteris oregonensis would seem to discourage 

that interpretation. 

The set of facts presented above impresses the present 

writers with the apparent futility of attempting to determine the stratigraphic position, within the Pennsylvanian, of the Spotted Ridge formation. A reliable 

interpretation of this paleontologic situation is doubtJess hindered by imperfections in our understanding of 

the stratigraphic ranges of North American Paleozoic 

plants and their relationships with European floras and 

by the uniquely limited specific composition of the flora. 

As it now stands, however, the floristic evidence appears to weigh almost as heavily for a late Pennsylvanian age determination as for an early one. For these 

reasons, it is the writers' opinion that pending the discovery of more complete paleontologic evidence, the age 

of the Spotted Ridge formation should be designated 

simply as Pennsylvanian, without further speculatory 

qualification. 

LITERATURE CITED 

Arnold, 0. A., 1953, Fossil plants of early Pennsylvanian type 

from central Oregon : Palaeontographica, Band 93, Abt. 

B, p. 61-68, pls. 24-25. 

Bell, '\V. A., 1940, The Pictou coal field, Nova Scotia: Canada 

Geol. Surv. Mem. 225. 

-- 1944, Carboniferous rocks and fossil floras of northel'n 

N-0va Scotia: Canada Geol. Surv. Mem. 238. 

Dawson, J. W., 1881, Notes on new Erian (Devonian) plants: 

Geol. Soc. London Quart. Jour., v. 37, p. 299-308, pls. 12-13. 

Elias, M. K., 1936, Character and significance of the late Paleozoic flora at Garnett, p. 9-23, in Moore, R. C., Elias, :M. K., 

and Newell, N. D., A "Permian" flora from the Pennsylvanian rocks of Kansas: Jour. Geol., v. 44, no. 1, p. 1-31. 

Florin, Rudolf, 1950, On female reproductive organs in the 

Cordaitinae: Acta Horti Bergiani, v. 15, no. 6, p. 111-134, 

pls. 1-6. 

Gothan, Walther, 1927, Fossile Pflanzen aus den Karru-Schichten der Umgebung des Ulugurugebirges in Deutsch-Ostrafrika: Palaeontographica, supp. 7, p. 145-152, pls. 18-19. 

Grand'Eury, F. C., 1877, Flore Carbonifere du departemente de 

la Loire et du centre de la France: Mem. Acad. Sci. Inst. 

France, v. 24, p. 1-624, pls. A-D, 1-34. 

Hirmer, Max, 1927, Handbuch der PaUiobotanik: Munich and 

Berlin. 

Kawasaki, Shigetaro, 1931, The flora of the Heian system, part 

2: Chosen (Korea) Geol. Surv. Bull., v. 6, no. 2, pls. 16--99. 

Kidston, Robert, 1924, Fossil plants of the Carboniferous rocks 

of Great Britain: Great Britain Geol. Surv. Mem., Paleontology,v.2,pt.5,p.377-522,pls.92-122. 

Kidston, Robert, and Jongmans, W. J., 1915-1917, A monograph 

of the Calamites of western Europe: Meded. van de Rijksopsporing van Delfstoffen, no. 7, text, p. 1-207, 1917; 

atlas, pls. 1-158, 1915. 

Lesquereux, Leo, 1880, Description of the coal flora of the Carboniferous formation in Pennsylvania and throughout the 

United States, Volume 2: Pennsylvania 2d Geol. Surv. Rept. 

p. p. 355-694. 

Merriam, C. W., 1942, Carboniferous and Permian corals from 

central Oregon: Jour. Paleontology, v. 16, no. 3, p. 372-381. 

Merriam, 0. W., and Berthiaume, S. A., 1943, Late Paleozoic 

formations of central Oregon: Geol. Soc. America Bull., v. 54, 

no. 2, p. 145-172. 

Miller, A. K., and Furnish, W. M., 1940, Studies of Carboniferous ammonoids, parts 5-7: Jour. Paleontology, v. 14, 

no. 6, p. 521-543. 

Nemejc, Frantisek, 1929, On some discoveries of fossil plant 

remains in the Carboniferous· districts of centr.al Bohemia 

(II): Bull. Int. Acad. Sci. Boheme, v. 30, p. 131-138, 

pls. 1-2. 

Packard, E. L., 1928, A new section of Paleozoic rocks in central Oregon: Am. Jour. Sci., 5th ser., v. 15, p. 221-224. 

-- 1932, A contribution to the Paleozoic geology of central 

Oregon : Carnegie Inst. Washington Pub. 418, p. 105-113. 

Read, C. B., and Merriam, C. W., 1940, A Pennsylvanian flora 

from central Oregon: Amer. Jour. Sci., v. 238, no. 2, 

p.107-111. 
224 CONTRIBUTIONS TO GENERAL GEOLOGY 

Schmalhausen, Johannes, 1879, Beitrage zur Juraflora Russlands: Mem. A.cad. Imp. Sci. St. Petersbourg (7), v. 27, 

no. 4, p. 1-96, pis. 1-16. 

Seward, A.. C., 1898, Fossil plants, Volume 1: Cambridge. 

--- 1919, ibid, Volume 4. 

Sterzel, J. T., 1907, Die Karbon- und Rotliegendflora im Grossherzogtum Baden: Grossh.-bad. geol. Landesanstalt Mitt., 

Band 5, no. 2, p. 347-892, pls.14-68. 

Stopes, M. C., 1914, The "Fern Ledges" Carboniferous flora of 

St. John, New Brunswick: Canada Geol. Surv. Mem. 41. 

White, David, 1899, Fossil flora of the lower coal measures of 

Missouri: U.S. Geol. Surv. Mon. 37. 

---1900, The stratigraphic succession of fossil floras of the 

Pottsville formations of the southern anthracite coal field : 

U.S. Geol. Surv. 20th A.nn. Rept., pt. 2. 

Zeiller, Rene, 1892, Etudes sur Ia tlore fossile des depots 

houillers et Permiens des environs de Brive: Etudes des 

gites mineraux de la France, v. 2, p. 1-132, pis. 1-15. 

--- 1899, Etude sur Ia fiore fossile de bassin houiller 

d'Heraclee (A.sie Mineure): Mem. Soc. Geol. France, 

Paleont., v. 9, no. 1, p. 57-91, pis. 16-22. 
INDEX 

Page 

Abstract ____ --·- __________________________________ ---------------______________ 211 

Annularia ____ _____ ---------- __ ---------------------------------- ___ __ ________ 216 

approximatijormis, Calamites _____________________ --------------_______________ 214 

Mesocalamites. _ _ _ ______ _____ _ ______ _ ____ __ _ __ _____ __ _ __ _____ _ _ __ _____ ____ 215 

Asterocalamites. __ --------- _________ ----------- ___ ---------- ______ ___ _____ ____ 214 

Asterophyllites _ --------- _______________________ --------------------------- __ 211, 218 

equi&etijormis. _______ --------- _______ ----------- _____ ---------- _________ !18, 222 

australicum, DicranophyUum _____ _____________________ -------------- ___ ___ ____ 219 

Avonia tuberculata _____________________________________ -------- ____ __ __ __ _ __ __ 214 

Berthiaume, S. A., Merriam, C. W., quoted ________________________________ 212-214 

berthiaumi, Lithostrotion (Lithostrotionella) ----------- _______ ___ ____ ___ ____ _____ 214 

Bibliography _______ -------------------- ____________________________________ 223-224 

biplicata, Camarophoria. ______ --------------------------------------- _____ ____ 214 

brevifolium, Dicranophyllum ____________ __________ ------------------- ___ _______ 220 

Calamites ____ ------ _________________________________________________________ 211, 214 

approximatiform'l8 ___ _______________________ ---.------------------ ___ ------- 214 

cistiijormis_ --- ________________________ ----------------- ____ ___ _______ _ ____ 214 

haueri. ___ --- ____________________________ -------------- _ __ _ __________ _____ 214 

hesperius __________________________________ ------------- _________________ 211, 215. 

ramijer ___ ------- _____________________ --------------- __ _ ___ _______ _ __ _ ____ 214 

roemerL __ ------ _____________________________ ----------- ______ _ _ _ ____ _ __ _ _ 214 

taitianus __ ____________________________ -------------------------- _ ____ _ __ _ _ 214 

Camarophoria biplicata__ _____ _ ______ _ ________ _ _____ ____ _______ _______ __ __ _____ 214 

karpinskyL ____________________________________________ ------------ __ _____ 214 

muta~ilis ____________ ______________ ---------- __ ________ _________ __________ _ 214 

Campophyllum readL ___ ____________ --------------------- ___ ------------ _____ 212 

cist#formis, Mesocalamites ____ _____________ ------------------------------------ 216 

Coffee Creek formation ____________________ -------------------------------- 211,212 

Cooper, G. Arthur, identitlcations bY-------------------------------------__ _ 214 

Cordaianthuslongibracteatus •• ------------------------------------- ___ 221,222, pl. 36 

Coyote Butte formation.----------------------------------------------- 211,213-214 

cistiijormis, Calamites_________________________________________________________ 214 

crookensis, Mesocalamites. ---------------------------------------- 215,216,222, pl. 34 

Dactylotheca ____________________ -------- _ -------------------------- ______ ____ _ 211 

plumosa ________________________________________________ -------'------ ___ 219, 223 

deliquescens, Phyllotheca____ __ ___ _____ __ _ ___ ___ __ _ ___ ______ ___ _ ________ _ _______ 218 

DibunophyUum oregonensis _____ __________________ ----------------- ___ __ _____ __ 212 

dichotoma, Schizopteris. ___ _ ___ __ ________ ___ __ _ __ _ _________ _ __ ___ _ __ _ ___ ____ _ __ 221 

dichotomum, Dicranophyllum ____ ______________________ ------------ _ _ _ ________ _ 219 

Dicranophyllum ____________ ______________ ------ _____________________________ 211, 219 

australicum___________ __ _____ ____ _ ___ __ _ _____ _ ______ ____ __ _________ ______ _ 219 

brevifolium __ _ -_- _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ __ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ __ _ _ _ _ _ 220 

dichotomum _________ _____________________ --------------------- ____ -------- 219 

dimorphum. ___________________________________________ ------------------- 219 

domini____________________________________________________________________ 220 

gallicum. _ -- __________ ------ _________ ------ _______________________ -------- 220 

garnettensis. _______________________ --------- _____________ --------------- __ 219 

glabrum ______ ________________________________ --------- _________ ----------- 219 

latifolium. _ --- ____________________________________________ --------------- _ 220 

rigidum ________ _______________ -------- ____________________________ 219, 222, pl. 37 

striatum. __ ---------- __________________ -------------------------------____ 220 

dimorphum, Dicranophyllum. _____________________ -------- ___ _____ ___ ___ __ ____ 219 

Discussion ____ ----------------------- _______________________________________ 222-223 

domini, Dicranophyllum_______________ _____ _ __ _ ______ __ _ __ ______ __ _ ___ ________ 220 

Eoasianites merriamf. ____________ __________ ----------------------------------- 214 

equisetijormis, Asterophyllites ____ ____________________ ------------ ____________ 218, 222 

erectus, Marchantites. _________________________________ --------------------- ___ 221 

Fusulinella. __ ------ ________________________ --------- ____ ------------------- __ 214 

gallicum, Dicranophyllum __ ______________________________________ ------------- 220 

garnettensis, Dicranophyllum ___ ___________ --------------- ______________ ------- 219 

Gigantella horizon ___________________________ ----- ________________ ---------- 212, 213 

sp ___ -- __ -------- _ _ __ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ __ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ 212 

glabrum, Dicranophyllum. __ -------------------------------------------------- 219 

Page 

haueri, Calamites _______ -----_------------------------------------------------- 214 

hesperius, Calamites _____________ -------------- ______ --- ____ --_-------------- 211, 215 

Mesocalamites ... --------------------------------------------- !15, 216,222, pl. 34 

Introduction _____ ------ ____________________ --- ___ ------- ____ ---------------- 211-212 

involuta, Marginijera ___ ______ • _____________ ----------------------------------- 214 

juresan.ensis, Juresania ____ ___________________ -____ ------ _- -------------------- 214 

Juresania juresanensis .• ------------------------ _ ------------------------- --- 214 

karpinskyf, Camarophoria .. -------- ______ ------------------------------------- 214 

Keyserlingina sp. ________________________ -- _______ - _-------------------------- 214 

Krotovfa pustulata _____ _______________________________ --- ____ ------------------ 214 

latifolium, Dicranophyllum _______ ----------------------- _ --------------------- 220 

Lepidodendrid branchleL------------------------------------------- 21-t 222, pl. 36 

Linoprodttctus sinuata ________________________ --------------------------------- 214 

Lithostrotion (Lithostrotion) packardL .. _____________ ------ __ ------------------ 212 

(Lithostrotionella) berthiaumL _________________ ---------------------------- 214 

gccidentalis ________ _ --------------------------- _______ ----------------- 214 

(Siphonoden.dron) oregonensis _____________________ __________ --------------- 212 

(Lithostrotion) packardi, Lithostrotion ________________________ ------------------ 212 

(Lithostrotionella) berthiaumi, Lithostrotion ___________ _ ------------------------- 214 

oecidentalis, Lithostrotion. -------------------------------- ______ ----------- 214 

longibracteatus, Cordaianthus. ________ ----- ________ -- __ --- ------- 221, 222, pl. 36 

Lycopsida ______________________ -------------------- __________ --- _____ ------_- 222 

mammatus, Productus. __________________ ------- ______ ------- ________ --------- 214 

Marchantites erect us. ------------ ___ -------------------------------- ___ ------- 221 

Marginifera involuta ________ _______________ ------------------------------------ 214 

Martiniopsis sp ______________ -------------------------- __________ -- _ ---------- 214 

Merriam, C. W., quoted .. ---------------------------------------------------- 214 Merriam, C. W., and Berthiaume, S. A., quoted ___________________________ 212-214 

merriami, Eoasianites _______ _______________ ---------- _____________ -____ -------- 214 

Mesocalamites _______ _________________________ -_______ --- ___ ------------------- 214 

approximatijormfs ___ _____________________________________________________ - 215 

cistiijormis _________________________________________ -_____ ----- __ ---------- 216 

crookensis.--------------------------------------------------- 215,216,222, pl. 34 

hesperius ... -------------------------------------------------- 215 216,222, pl. 34 

ramijer ____ ------------------------------------------------------·--------- 216 

roemeri. _____ ------------------------------------------------------------- 222 

sp ______________________________ --------------- __________________ 116, 222, pl. 34 

mutabilis, Camarophoria. ____________ -------- _________________ ---------------- 214 

Notothyrts nudeola _____ _ ---------------------- ___ ----------------------------- · 214 

n. sp __________ ----------------------------------------------------------- 214 

nucleola, Notothyris. ---------------------------------------------------------- 214 

occidentalis, Lithostrotion (Lithostrotionella) _____ _____ --- _____ .. - _-.-------- 214 

ochocoensis, Waagenophyllum __________ ---------------------------- _ ----------- 214 

oregonensis, Dibunophyllum ________ ------------------------------------------- 212 

Lithostrotion (Siphonodendron) ______ --------------------------- _ ---------- 212 

Pecopteris ________________________ ---------- ________ -~211;216, 219, 222, 223, pl. 36 

packardi, Lithostrotion.(Lithostrotion) ____ ___ -- __ --------------------------- 212 

Parafusulina, new species of___________________________________________________ 214 

paulinensis, Phyllotheca ______________________________________ 216, 222, 223, pis. 34, 35 

Pecopteris oregonensis------------------------------------ 211,216,219, 22:!, 223, pl. 36 

plumosa. _ -------- __ ------------------------------------------------------ 223 

Phyllotheca. __ -------- __________________ ------- _______ ---------------------- 211, S16 

deliquescens ______________________________ -_______ --- _ ------------- __ ------ 218 

paulinensis n. SP----------------------------------------- S16, 222,223, pis. 34,35 

rallii ______________ --------------------------------------------- 211, 216, 218, 223 

uluguruana ------------------ __ ------------- _ ---------------------------- 218 

plumosa, Dactylotheca ____________ ___ ---------------------------------------- 219, 223 sp _ _ _ _ _ _ _ _ _ _ _ _ _ _ __ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ __ _ _ _ ___ __ ___ _ _ _ _ _ _ __ 211 

Pecopteris _____________________ -____ ------- ___ ------- __ -------- __ --------__ 223 

porrectus, Productus. _____________ ---------------- __ -------------------------- 214 

Problematica ________________________ --------------------- ____ -------------- 221, 222 

Productus mammatus __ __________________ ------------------------------------- 214 porrectus __ ______________________________ -- ___ ------- ______ -__ -__ -------- _ _ 214 

225 
226 INDEX 

Pteropsida ___________________________________________________________________ _ 

pU8tulata, Krotovia ___ ______ --------- _______________________________ -----------

Page 

222 

214 

rallii, Phgllotheca. __________________________________________________ 211, 216, 218, 223 

ram~;s~~:===~~~~~::~ ~: ~ ~ ~ ~ ~: ~ ~ ~ ~ ~ ~ ~ ~ ~: ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~~ ~ ~ ~ ~ ~ ~ ~ !~ ~ ~ ~ ~ ~ ~: ~~: ~ ~ ~~: readi, Campophgllum. _ _ ___ ___ _ ___ ____ __ _ __ _ _ __ _ __ _ __ __ _____ ___ _ _ ___ ___ _______ 212 

Rhgnchopora n. sp_ ----------------------------------------------------------- 214 rigidum, Dicranophyllum _____________________________________________ 219,222, pl. 37 

roemeri, Calamites ___ ----- _____________________________________________ ------- 214 

Mesocalamites ___ ----- ________ ------ _____ ------------- _______ ------------- 222 

Roots of unknown affinitY-------------------------------------------- 221-222, pl. 37 

Schizopteris dichotoma ______ __________________________________________ --------- 221 

trichomanoides _____________ ____ ----------------------------------- 221,222, pl. 36 

Schwagerina __ ------------------ _ __ _ ___ _____ _ ___ _ ___ __ _ __ _ __ _ _ ___ _______ ______ 214 

sinuata, Linoproductus____________________ _____ __ __ __ ____ _ __ _ ___ _ __ ______ _ ____ 214 

(Siphonodendron) oregonensis, Lithostrotion__ ____ __ __ __ _ __ _ _ __ _____ __ _ ____ __ ___ 212 

Sphenopsida__________________________________________________________________ 222 

Sphenopteris__________________________________________________________________ 211 

Spirijer striatus. --------- ____________ ------------ _______ _ __ __ _ ____ ___ __ _ ___ __ _ 212 

Spiriferella, n. sp ___ ------------- _ _ ______ ___ _ ___ ____ ___ __ _ _ __ _ _______ __ ______ _ 214 

Spotted Ridge formation.---------------------- _________________ --------- __ 211,212 

0 

Page 

Stigmarian rootstock. ______________ ------_---_------------------------------- 222 

Striatijera ___ _________________________________ ------ __ -- __ --------------------- 212 

Stratigraphy, Grindstone-Twelvemile Creeks Paleozoic Inlier _______________ 212-214 

striatum, Dicranophgllum_ ------ _ --------------------------------------------- 220 

striatus, Spirifer --------------------------------------------------------------- 212 Systematic descriptions ________________________ --- _________________ --------- 214-222 

taitianus, Calamites ___________ ----- ____ --------------------------------------- 214 

Tertiary lava _________ ------ ____ --------_------------_------------------------ 213 

Tetrataxis sp ______ ------------------ _ ----------------------------------------- 212 trichomanoides, Schizopteris __________________________________________ 221,222, pl. 36 

Triticites ___ ______________________________ -- ______________ ----- __ ---- _--------- 214 

tuberculata, Avonia ____ ---------------- _ --------- _ --- _ ------------------------- 214 

Tuckers Butte _______ ---------------- __ --------- ____ ------_------------------- 213 

uluguruana, Phyllotheca ____________ ______ ----- ___ ------------- _ -- _______ -- __ -- 218 

Waagenoconcha n. SP--------------- ____ ------- ___ --- _ --- ______ -- _ ------------- 214 

Waagenophyllum ochocoensis. _ ------------------------------------------------ 214 

washburni. __ ------------------------------------------------------------- 214 sp. a______________________________________________________________________ 214 

sp. b ______________________ --------------------------- _________ ---- __ --- _ __ 214 

washburni, Waagenophyllum._ ------ ___ ------- ________ -------- ________ -- _- _ _ _ _ 214 
PLATES 34:-37 
PLATE 34 

[All figures natural size unless otherwise indicated on plate] 

FIGURES 1-2. Mesocalamites sp. (p. 216). 

1. Fragment of a mesocala:rnitean pith cast, containing one node. USNM 407'05. 

1a. Same specimen, enlarged to show the superposed ribs and convergence of the ribs toward a common point on 

the nodal line. · 

2. Fragment of a mesocalamitean pith cast, containing two nodes and one complete internode. Note the long, 

narrow ribs. USNM 40706. 

3. Mesocalamites hesperius (Arnold) Mamay and Read, n. comb. (p. 215). Fragment of pith cast, shown for comparison 

with Mesocalamites crookensis Mamay and Read. USNM 40707. 

4, 4a. Mesocalamites crookensis Mamay and Read, n. sp. (p. 215). 

4. General view of the holotype. USNM 40708. 

4a. Part of the holotype enlarged to show the preponderant superposition of the ribs at the nodes. 

5. Two whorls of small (?) sporangia, possibly from an articulate cone. In the whorl shown at the bottom of the photograph, the faint lines opposite the sporangia are suggestive of subtending bracts. USNM 40709. 

6-8. Phyllotheca paulinensis Mamay and Read, n. sp. (p. 216). 

6. A large stem fragment, showing attachment of lateral branches and foliage. Syntype, USNM 40710. 

7. A stem fragment with a small lateral branch attached, showing the general attitude of the leaves. Syntype, 

USNM 40711. 

8. A specimen with four leaf whorls; basal fusion of leaves is shown in the two lowermost whorls. Syntype, 

USNM 40712. 

l 
GEOLOGICAl, SURVEY PROFESSION AL PAPER 2i4 PLATE 34 

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MESOCALAMITES AND PHYLLOTHECA 
PLATE 35 

[Ail figures natural size unless~otherwise indicated on plate) 

FIGURES 1-6. Phyllotheca paulinensis Mamay and Read, n. sp. (p. 216). 

1. Fragment of an axis bearing a terminal cone and three lateral ones, with interposed sterile whorls. Syntype, 

USNM 40713. 

2. Large fragment of a stem (slightly reduced), showing the attachment of leaves, lateral branches, and cones. 

The branch departing from about the middle of the left side of the axis bears three small cones. Syntype, 

USNM 40714. 

3. Part of a foliar whorl, showing basal fusion of the leaves. Syntype, USNM 40715. 

4. A foliar whorl containing parts of at least 20 leaves. Syntype,-USNM 40716. 

5. Fragment of an unusually thick cone. Syntype, USNM 40717. 

6. An unusually long cone fragment, showing distribution and attitude of the bracts. Syntype, USNM 40718. 
GEOLOGICAL SURVEY PROFESSIONAL PAPER 274 PLATE 35 

1 

3 

PHJ:LLOTHECA PAULINENSIS MAMAY AND READ, N. SP. 
PLATE 36 

[All!figures natural size unless otherwise indicated on plate] 

FIGURES 1-7. Pecopteris oregonensis Arnold (p. 219). 

1. Fragment of rachis, showing surface punctations and spinelike emergences. USNM 40719. 

2, 3. Specimens of sterile foliage, illustrating differences in size and shape of pinnules. Figure 2, USNM 40720; 

figure 3, USNM 40721. 

4. Fertile specimen; laminar tissues apparently decayed before preservation, leaving only the sporangia. USNM 

40722. 

5, 6. Large aphlebiae. Figure 5, USNM 40723; figure 6, USNM 40724. 

7. Frond fragment, illustrating the typical aspect of this species. USNM 40725. 

8-9. Cf. Schizopte1·is trichomanoides Goeppert (p. 221). 

8. Specimen showing the pattern of repeated bifurcations. USNM 40726. 

9. Fragment showing fanlike general outline. USNM 40726. 

10. Cf. Cordaianthus longibracteatus Florin (p. 221). 

Fragment of an axis bearing several bracts and faintly preserved axillary budlike structures. USNM 40727. 

11-12. Cf. Asterophyllites equisetiformis Brongniart (p. 218). 

11. Tip of a vegetative branch, thickly covered with young leaves. USNM 40728. 

12. Rock slab bearing numerous specimens of foliage and fragments of two poorly preserved axes. USNM 40729. 

13. ?Lepidodendroid branchlet (p. 214). 

Slender axis bearing small leaves and showing faint surface ornamentation reminiscent of Lepidodend1·on leaf cushions. 

USNM 40730. 
GEOLOGICAL SURVEY PROFESSIONAL PAPER 274 PLATE :lti 

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PECOPTERIS, ?SCHIZOPTERIS, ?CORDAIANTHUS, ASTEROPHYLLJTES, AND ?LEPIDODENDROID BRANCHLET 
PLATE 37 

[All figures natural size unless otherwise indicated on plate] 

FIGURES 1-2. Undetermined roots (p. 22). 

1. Specimen showing the median vascular strand, longitudinal striations of the dermal layer, and circular punctations on the surface. A lateral rootlet is shown departing from the left margin of the specimen; the connection of the vascular strand of the lateral rootlet with that of the parent root is also shown. USNM40731. 

2. Rock slab containing several root fragments of different sizes. USNM 40732. 

3-lOa. Dicranophyllum rigidum Mamay and Read, n. sp. (p. 219). 

3. Fragment of a foliated axis, showing decurrent leaf bases. Syntype, USNM 40733. 

4. Fragment of a defoliated axis, showing vertically elongated leaf cushions. Syntype, USNM 40734. 

5. Fragment of a long, slender axis, bearing loosely arranged leaves. Syntype, USNM 40735. 

6. Rock surface bearing two axes. The axis toward the right is densely covered with long leaves, some of which 

bifurcate twice toward the left. Syntype, USNM 40736. 

7, 7a. Single leaf. Note the spinelike ultimate divisions, as contrasted with the longer ones shown in figures 8 

and Sa. Syntype, USNM 40737. 

8, Sa. Single leaf, showing twice-bifurcated lamina with four ultimate segments. Syntype, USNM 40738. 

9. Tip of an axis, thickly clothed with leaves. Note the rigid aspect of the foliage. Syntype, USNM 40739. 

10, lOa. Fragment of a leafy axis. Note the bifurcation of the leaves, their shortness, and their lax arrangement as compared with the specimen shown in figure 6. Syntype, USNM 407 40. 
GEOLOGICAL SURVEY PROFESSIONAl, PAPER 274 PLATE 37 

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UNDETERMINED ROOTS AND DICRANOPHYLLUM RIGIDUM MAMA Y AND READ, N. SP.