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UNITES SPATES DEPARTMENT OF THE INTERIOR 

Harold L. I ekes, Secretary

GEOLOGICAL SURVEY 

W. C. Mendenhall, Director

Professional Paper 186—B

FOSSIL FLORA

OF THE WEDINGTON SANDSTONE MEMBER 

OF THE FAYETTEVILLE SHALE

BY

DAVID WHITE

Shorter contributions to general geology, 1936

UNITED STATES

GOVERNMENT PRINTING OFFICE 

WASHINGTON : 1937

For sale by the Superintendent of Documents, Washington, D. C. ------ - Price 10 cents
CONTENTS

Page

Abstract ____ _________________________________________________________________________________________________ 13

Stratigraphy and distribution of the plant-bearing beds_______-_-_---_„_--__-_-__--_-____________-_-__---_-_-_-_ 13

Plant localities-___-_____-______________________________________________„____________________________________ 14

General composition of the Wedington flora,____________________________________________________________________ 14

Age of the flora of the Wedington sandstone member_____________________________________________________________ 15

Relations of the Wedington flora to that of the coal-bearing shale of the Morrow group of Washington County, Ark_____ 16-

Environment of the Wedington flora.____--_________________--____-_____--__--__-_--_______-___--___--_-_--___- 17

Descriptions of the species.___________________________________________________________________________________ 17

ILLUSTRATIONS

Page 

PLATES 4-9. Fossil flora of the Wedington sandstone member of the Fayetteville shale ______________________________ 42

n
FOSSIL FLORA OF THE WEDINGTON SANDSTONE MEMBER OF THE

FAYETTEVILLE SHALE

By DAVID WHITE 1

ABSTRACT

The Wedington sandstone member of the Fayetteville shale 

has yielded fragmentary remains of fossil plants at several 

localities in the Winslow quadrangle, Arkansas. These forms, 

though many of them are indifferently preserved, are extremely 

significant in that they represent the first Mississippian land flora 

to be reported in the Midcontinent region. The age of the beds 

containing the flora is established by invertebrates, as well as 

by plants, to be early upper or middle Chester. The flora is 

related to that of the Chester group of the Eastern Interior 

basin and to beds of Chester age in the Appalachian trough 

through certain of its filicinean, calamarian, and lycopodiaceous 

forms. Likewise it is similar, in certain features, to standard 

lower Carboniferous floras of Europe. The Mississippian aspect 

of the flora is modified somewhat by the presence of a lower 

Pottsville or Namurian element, pointing to upper Chester age. 

This flora, however, contains no forms in common with the large 

assemblage of plants described by Lesquereux from the Bloyd 

shale (middle Pottsville) of the same region.

It is suggested that the plants grew in an environment not 

entirely favorable to the development of large size. The climate 

was probably marked by a seasonal deficiency of rainfall.

The flora, as it is now known, includes 35 species. It contains 

representatives of the Filicales, the Lycopodiales, the Equisetales, the Sphenophyllales, and the Pteridospermae.

STRATIGRAPHY AND DISTRIBUTION OF THE PLANTBEARING BEDS

"Wedington sandstone" is the name given by 

Adams 2 to a sandstone in the upper part of the Fayetteville shale, a formation of upper Mississippian (Chester) 

age in northwestern Arkansas and eastern Oklahoma. 

It is classified as a member of the Fayetteville shale, 

though on account of frequency of repetition, it is 

often casually mentioned in this paper as the Wedington sandstone. The type locality of the sandstone is 

Wedington Mountain, in northern Washington County, 

Ark., in the southwest corner of the Fayetteville 

quadrangle.3 The sequence of the beds in the Winslow 

quadrangle,4 immediately adjacent on the south, 

from which the plant material has been obtained, is 

briefly summarized as follows:

1 This report was essentially completed by Dr. White before his death, Feb. 7, 

1935. The additions and corrections which have since been made are small editorial 

modifications.

2 Adams, G. I., Zinc and lead deposits of northern Arkansas: IT. S. Geol. Survey 

Prof. Paper 24, p. 27,1904.

3 Adams, G. I., and Ulrich, E. O., IT. S. Geol. Survey Geol. Atlas, Fayetteville 

folio (no. 119), p. 4, 1905. 

1 Purdue, A. H., TJ. S. Geol. Survey Geol. Atlas, Winslow folio (no. 154), 1916.

Sequence of beds in Winslow quadrangle, Arkansas

Pennsylvanian:

Morrow group: Feet

Bloyd shale: Blue shale, gray and yellowish 

shale, and carbonaceous shale, including 

two marine limestones—the Kessler 

above and the Brentwood below—and a 

thin dark intervening shale—the coalbearing shale—which includes the Washington County coal_________________ 100-220

Hale formation: Shale, sandstone, and thin

limestone, marine___________________ 100-200

Unconformity. 

Mississippian:

Pitkin limestone: Gray coarse-textured fossiliferous limestone,_________________________ 10-40

Fayetteville shale: Black thinly laminated carbonaceous shale containing calcareous concretions and limestone locally near base. 

(The Wedington sandstone member is a heavy 

light-gray to brown cross-bedded sandstone, 

normally capped by greenish to bluish shale,' 

at the top of the Fayetteville shale)_______ 150-300

Unconformity.

Boone limestone: Light-gray limestone, containing chert in beds and lenses._______________ 100+

Normally the Wedington sandstone member is 

overlain by bluish shale that weathers yellowish and 

has a maximum thickness of 60 feet. In some places 

in northwestern Arkansas the shale is lacking and the 

Pitkin limestone, the youngest Mississippian formation 

of the region, rests directly on the Wedington sandstone 

or even on underlying beds of the Fayetteville shale.

The sandstone is lenticular and is 150 feet or less in 

thickness. It reaches nearly its maximum thickness 

in the vicinity of Prairie Grove and Lincoln, in the 

northwest corner of the Winslow quadrangle, where 

the fossil plants here described were found. It is a 

hard, resistant sandstone, varying from white to rusty 

dark gray and greenish gray, is usually rather coarse, 

and in places is ripple-marked and cross-bedded. 

Certain layers carry considerable mica, and the plantbearing beds in the region contain numerous white to 

dark-blue clay pebbles of moderate size and generally 

well rounded, so that, locally at least, the Wedington 

sandstone member is conglomeratic.

13
14 SHOETER CONTRIBUTIONS TO GENERAL GEOLOGY, 1936

The distribution of the Fayetteville shale is shown 

approximately on the geologic maps of Arkansas 5 and 

Oklahoma 6 and is described by Croneis,7 who, on the 

basis of the marine invertebrates, correlates the Wedington sandstone member with the Chester group. 

Marine invertebrates are relatively rare in the sandstone, where the fossil plants are found in comparative 

abundance. Lists of invertebrate fossils are given by 

Purdue and Miser 8 and by Croneis.9 The sandstone is 

likewise regarded by the paleontologists of the United 

States Geological Survey as of Chester age.

The plants buried in the Wedington sandstone bear 

evidence of destructive water wear. The identifiable 

debris consists mainly of fragments of the resistant 

outer cortex and roots of Lepidodendron and pieces of 

woody species belonging to the calamarian group. 

Large numbers of seeds having a hard outer shell 

were washed into the sand here and there, and a few 

broken and badly worn fragments of cones also are 

found. Fernlike plants, probably belonging to the 

pteridosperms, were present, but only very small fragments have yet been found in the sandstones and interbedded shales, though portions of large water-worn 

petioles of at least two genera have been collected.

The occurrence of rather abundant plant debris 

together with numerous shale pebbles points to the 

probable contemporaneous exposure of land not far 

from the fossiliferous localities, in spite of the fact that 

a few brachiopods also are mingled with the vegetable 

fragments. Such exposures not remote from the plantbearing deposits accord with the description by Purdue 

and Miser of deformations taking place in the Harrison 

and Eureka quadrangles after the greater part of the 

Fayetteville shale had been deposited. 10 Apparently 

the Wedington sandstone marks a minor erogenic 

movement in this region near the end of Chester time.

PLANT LOCALITIES

Plants were first found in the Wedington by H. D. 

Miser in 1928 at localities near Lincoln, Ark. These 

and other places, some of them near Prairie Grove, 

Ark., he revisited in 1929 in company with C. L. Cooper 

and in 1930 in company with L. G. Henbest and me, 

when most of the present collection was gathered. 

The plant localities were revisited in 1931 by Mr. 

Miser, accompanied by Charles B. Read, and again in 

1932 by Mr. Miser. The collected material consisted 

mostly of sandstone but included some plant-bearing 

shale interbedded in the sandstone.

Owing apparently to the destruction of the more 

fragile plant material before its final burial in the sand,

5 Branner, G. C., Geologic map of Arkansas, Arkansas Geol. Survey, 1929.

• Miser, H. D., Geologic map of Oklahoma, U. S. Geol. Survey, 1926.

7 Croneis, Carey, Geology of the Arkansas Paleozoic area: Arkansas Geol. Survey 

Bull. 31, p. 69, 1930.

s Purdue, A. H., and Miser, H. D., U. S. Geol. Survey Geol. Atlas, Eureka SpringsHarrison folio (no. 202), p. 13,1916.

• Croneis, Carey, op. cit., p. 71.

10 Purdue, A. H., and Miser, H. D., op. cit., p. 16.

the Wedington flora admits the recognition of but few 

species, yet it is of unusual interest, for it is the first 

indubitably Mississippian land flora to be discovered 

in the Midcontinent region. Therefore the species 

are described and illustrated in detail in the following 

pages, in order that the record may be of use to stratigraphers as well as paleontologists who may be concerned with comparing the Wedington flora with others, 

especially those of the Jackfork sandstone and the 

Stanley shale in the same region, concerning the age of 

which there is wide difference of opinion.

The precise localities from which Wedington plants 

were obtained are as follows:

1. Bob Kidd Hollow, south of United States Highway 62. 

3.2 miles southwest of Prairie Grove, Ark.; collected by H. D. 

Miser, L. G. Henbest, and David White, 1930 (U. S. Geological 

Survey lots 8075 and 8140), and by H. D. Miser and C. B. Read, 

1931 (U. S. Geological Survey lot 8264).

2. Cane Hill, Ark.; collected by H. D. Miser, L. G. Henbest, 

and David White, 1930 (U. S. Geological Survey lot 8144).

3. About 2 miles southwest of Prairie Grove, Ark.; collected 

by H. D. Miser, L. G. Henbest, and David White, 1930 (U. S. 

Geological Survey lot 8145), and by H. D. Miser and C. B. Read, 

1931 (U. S. Geological Survey lot 8266).

4. Lincoln-Summers road, 4 miles west of Lincoln, Ark.; 

collected by H. D. Miser and C. B. Read, 1931 (U. S. Geological 

Survey lot 8267).

5. Six-tenths of a mile south of junction of State Highway 99 

and United States Highway 62, 4 miles west of Lincoln, Ark.; 

collected by H. D. Miser and C. B. Read, 1931 (U. S. Geological 

Survey lot 8268).

GENERAL COMPOSITION OF THE WEDINGTON FLORA

The flora here described is the first land flora to be 

made known from beds of unquestioned Mississippian 

age in the entire southwestern portion of the United 

States. Accordingly, its correlative value and its importance as a paleobotanic datum plane with which to 

compare other fossil floras of the upper Mississippian 

and lower Pennsylvanian of the region exceed its meager worth as illustrating the plant life of the region 

in Wedington time.

Though some of the species in this flora are adequately represented in the collections, there is an unfortunately large percentage of forms of which only 

few and very small fragments—too meager, in fact, 

for satisfactory identification or description—have 

been obtained. Most of these are ferns or fernlike 

types. In treating them I have leaned toward describing as new species those that are not recognized 

as old ones, often basing specific differentiations on 

glaringly insufficient material, and have illustrated 

them very fully. This treatment should promote the 

discovery of additional and more ample illustrative 

material, which in turn should lead to the more definite 

and permanent identification and description of the 

genera and species. This procedure will assure greater 

completeness and clarity of the systematic as well as 

the distributional records.
FOSSIL FLORA OF THE WEDINGTON SANDSTONE 15

The genera and species in the present collections are 

listed below:

Adiantites minima White, n. sp.

Cardiopteris hirta White, n. sp.

Cardiopteris sp.

Neuropteris sp.

Rhacopteris sp.

Khodea cf. R. subpetiolata (Potonie) Ngmejc.

Rhodea cf. R. moravica (Ettingshausen) Stur.

Sphenopteris cf. S. communis Lesquereux.

Sphenopteris (Palmatopteris) erectiloba White, n. sp.

Sphenopteris (Calymmatotheca) mississippiana White, n.

sp.

Sphenopteris cf. S. obtusiloba Brongniart. 

Sphenopteris cf. S. schimperiana Goeppert. 

Telangium? sp.

Rhynchogonium fayettevillense White, n. sp. 

Carpolithus inquirenda White, n. sp. 

Lepidodendron henbesti White, n. sp. 

Lepidodendron occidentale White, n. sp. 

Lepidodendron purduei White, n. sp. 

Lepidodendron cf. L. veltheimianum Sternberg. 

Lepidodendron wedingtonense White, n. sp. 

Lepidodendron sp. 1. 

Lepidodendron sp. 2. 

Stigmaria arkansana White, n. sp. 

Stigmaria wedingtonensis White, n. sp. 

Bothrodendron sp.

Lepidophyllum sagittatum White, n. sp. 

Lepidostrobus occidentalis White, n. sp. 

Lepidocystis chesterensis White, n. sp. 

Archaeocalamites fayettevillensis White, n. sp. 

Archaeocalamites gracilentus White, n. sp. 

Archaeocalamites umbralis White, n. sp. 

Archaeocalamites wedingtonensis White, n. sp. 

Archaeocalamites? sp.

Chlamidostachys chesterianus White, n. gen. and sp. 

Sphenophyllum? sp.

The Wedington flora is of mixed composition. It 

comprises ferns and fernlike plants, calamarian forms 

representing Archaeocalamites, and lepidophytes, of 

which Lepidodendron is the most abundant. No 

typical Pennsylvanian Catamites and no representatives 

of the genera Aster ophyllites, Annularia, Mariopteris, 

Alethopteris, Sigillaria, or Cordaites have yet been 

found.

Though most of the species in the Wedington flora 

are here described for the first time, nearly all are 

closely related to species previously known, either in 

the upper Mississippian or in the lowest Pennsylvanian.

AGE OF THE FLORA OF THE WEDINGTON SANDSTONE 

MEMBER

The age of the beds containing the Wedington flora 

is not now subject to question, being approximately 

established by the sequence of marine faunas, with an 

associated flora, in the series of formations which compose type sections of the upper Mississippian and lower 

Pennsylvanian for this region.

The plant-bearing sandstones of the Wedington are 

normally intercalated in marine shales which, where 

not eroded, are in turn overlain by 15 to as much

as 100 feet of Pitkin limestone, formerly known as 

the ^Archimedes limestone. 11 The Pitkin formation, 

rich in marine life, embracing a few Pennsylvanian 

forms in a fauna overwhelmingly Mississippian in 

facies, comprises the beds of latest Mississippian age 

yet recognized in the Southwestern Interior basin. On 

the evidence of the marine invertebrates, examined by 

many paleontologists, it is referred to the upper 

Chester, whereas the Fayetteville shale, which in its 

upper part embraces the Wedington sandstone member, is regarded as of middle and upper Chester age. 

A slight unconformity at the base of the Pitkin permits 

the limestone locally to rest directly on the Wedington 

sandstone member, or even on underlying shale of the 

Fayetteville.

From the paleobotanist's point of view, so far as the 

criteria are yet in hand, the Wedington is evidently 

bound to the upper Mississippian by its large-pinnuled 

Rhacopteris, which has very close relatives in the beds 

of Chester age in the Appalachian trough as well as in 

western Europe; by its species of Cardiopteris, which 

differ but slightly from one widely spread in the upper 

Mississippian of the Appalachian trough and the 

Eastern Interior basin; by its Archaeocalamites gracilentus and the possibly associated Chlamidostachys 

chesterianus, which have European relatives in the 

upper Mississippian Pothocites; by its Lepidodendron 

occidentale, which differs only in the greater altitude of 

its leaf scar from the typical Lepidodendron volkmannianum, found both in Europe and in the American 

Chester, where it is characteristic of that stage in the 

Appalachian trough and the Eastern Interior basin; 

by its Lepidophyllum sagittatum, which represents a 

group of rather small, narrow, tapering, sword-pointed 

leaves of the Old World and Appalachian upper Mississippian; by its Lepidocystis chesterensis, present in 

the beds of Chester age in the Appalachian trough and 

possibly specifically identical with a form in the Mississippian limestone of Silesia; by its Stigmaria wedingtonensis, a form with radiately areolate leaf scars 

associated with the L&pidodendron volkmannianum 

group; and by its Rhynchogonium fayettevillense, which 

is most closely related specifically to European forms 

from the Mississippian limestone of Silesia, the Calciferous Sandstone of Scotland, and the Mississippian of 

the Arctic zone. All these forms are characteristically 

and exclusively Mississippian. Furthermore, the distribution of the forms specified above in beds of Chester 

age in the Appalachian and Eastern Interior basins 

leaves no room for doubt as to the correlation of the 

Wedington with the Chester group, the upper division 

of the Mississippian series in the Eastern Interior 

basin. These plant forms would proclaim the Chester

11 A dagger (t) preceding a geologic name indicates that the name has been abandoned or rejected for use in classification in publications of the U. S. Geological 

Survey. Quotation marks, formerly used to indicate abandoned or rejected names, 

are now used only in the ordinary sense.
16 SHORTER CONTRIBUTIONS TO GENERAL GEOLOGY, 1936

age of the deposits even if there were no associated 

invertebrate fossils to point out the position of the 

Wedington in the Mississippian column of the Southwest.

On the other hand, the flora is connected with the 

Pennsylvanian by a large element present in the Namurian or the next higher stages of the lower Pennsylvanian, included in the American Pottsville group. 

Among these mention may in particular be made of 

Sphenopteris (Calymmatotheca) mississippiana, which 

approaches extremely closely the earliest phase of the 

group of forms generally included under Sphenopteris 

or Calymmatotheca hoeninghausii. In the same category may be placed the Adiantites, the Rhodea, the 

Neuropteris, the group Mesocalamites, in which most 

of the forms of Archaeocalamites from the Wedington 

find their place; also Lepidodendron wedingtonense, 

which appears to have direct ancestral connection with 

Lepidodendron wortheni and L. brittsii, at the base of 

the Allegheny formation; Lepidodendron cf. L. rimosum; Lepidostrobus occidentalis, closely related to Lepidostrobus variabilis Lindley and Button; and several 

lepidodendroid forms, including that showing a cone 

scar and tentatively assigned to Bothrodendron, which 

fall within the comprehensive group generally referred 

by paleobotanists under the collective term Lepidodendron veltheimianum.

Several of the plants enumerated above appear to 

be present in the uppermost Mississippian of Europe 

as well as of America, though they range upward into 

the Namurian and some of them into the Westphalian, 

which is nearly equivalent to the middle and upper 

Pottsville of the Appalachian trough. On the whole, 

however, though the flora in hand exhibits ties connecting it with the basal Pennsylvanian, and especially 

the Namurian, its exclusively Mississippian representatives are sufficient in type and in number to demand its 

reference to the Chester Mississippian, though if considered only from the present knowledge of the fossil 

flora, the Wedington sandstone would be classed as 

upper Chester.

RELATIONS OF THE WEDINGTON FLORA TO THAT OF 

THE COAL-BEARING SHALE OF THE MORROW GROUP 

OF WASHINGTON COUNTY, ARKANSAS

The geographically nearest flora of Pennsylvanian 

age which has been described and with which the flora 

of the Wedington sandstone member may be compared 

is the well-known flora recorded from what was formerly known as the coal-bearing shale of Washington 

County, Ark., which occurs in the same region and in 

the same vertical section as the Wedington sandstone.

The Morrow group, in which the coal-bearing shale 

has its place, is in this region not over 400 feet thick. 

It rests usually upon the Pitkin limestone, or where the 

Pitkin has been removed by erosion it may lie upon 

the Wedington sandstone member or even on the lower

part of the Fayetteville shale. At the base of the 

Morrow group is the Hale formation, consisting of 

shales, sandstones, and thin limestones, 80 to 300 feet 

in total thickness; above which lies the Bloyd shale, 

reaching a maximum thickness of 175 feet and containing near its base the Brentwood limestone member 

(whose maximum thickness in the Fayetteville quadrangle is 80 feet) and higher in the section the Kessler 

limestone member (in some places only 2 to 4 feet thick 

but reaching a maximum thickness of 70 feet in the 

Fayetteville quadrangle). Between these limestone 

members is an interval, usually 10 to 20 feet but in 

places 100 feet, occupied by shales that contain a thin 

coal formerly mined at several points in the Fayetteville 

quadrangle. This shale is known as the coal-bearing 

shale and the coal as the Washington County coal. 

More than 120 species, composing a well-balanced flora, 

were described or recorded by Lesquereux 12 as coming 

from this stage and vicinity. In his reports the plants 

are recorded as from a sub conglomerate stage, then 

believed to be upper Mississippian, as the base of the 

Winslow formation, which lies upon the Morrow group, 

a short distance above the Kessler limestone, is marked 

by a quartz conglomerate regarded at that time as the 

fMillstone grit, the base of the Pennsylvanian or upper 

Carboniferous.

A review of the plants from the coal-bearing shale by 

me in 1893 resulted in the reference of that shale to a 

stage in the upper part of the middle Pottsville or 

possibly the extreme basal portion of the upper Pottsville and the consequent transfer of the Kessler limestone and overlying beds to the Pennsylvanian. Later, 

on account of the large Pennsylvanian element in the 

fauna, the lower portion of the Bloyd formation, embracing the Brentwood limestone, with its associated 

shales and sandstones, and the Hale sandstone, were 

placed in the Morrow group and likewise referred to 

the basal Pennsylvanian. All the formations carry 

abundant marine local faunas, which are listed by 

Miser. 13 The general faunas of the Morrow group and 

their stratigraphic distribution have been discussed 

somewhat fully by Mather. 14

It is noteworthy that so far as the Wedington flora 

is known at the present moment, no species in it is 

found also in the large flora of the coal-bearing shale 

in the Morrow group. This fact accords with the 

length of the interval between the early upper or possibly 

the latest middle Chester and a stage lying probably in 

the upper part of the middle Pottsville. Certainly

» Lesquereux, Leo, Botanical and paleontological report on the Geological State 

Survey of Arkansas, in Owen, D. D., Second report of a geological reconnaissance of 

the middle and southern counties of Arkansas, pp. 295-399, Philadelphia, 1860; Description of the coal flora of the Carboniferous formation in Pennsylvania and 

throughout the United States: Pennsylvania 2d Geol. Survey Kept. P, 3 vols. 

and atlas, 1879-84.

" Purdue, A. H., and Miser, H. D., U. S. Geol. Survey Geol. Atlas, Eureka 

Springs-Harrison folio (no. 202), pp. 14-15, 1916. See also Croneis, Carey, Geology 

of the Arkansas Paleozoic area: Arkansas Geol. Survey Bull. 3,1930.

» Mather, K. F., The fauna of the Morrow group of Arkansas and Oklahoma: 

Denison Univ., Sci. Lab., Bull. 18, pp. 59-284.1915.
FOSSIL FLORA OF THE WEDINGTON SANDSTONE 17

the equivalent at least of the entire Lee formation, 

over 1,200 feet thick, embracing the lower part of the 

Pottsville group of the Appalachian trough, was deposited in the Appalachian region in Pennsylvanian 

time before beds contemporaneous with the coalbearing shale were there laid down.

Of the plant life of that portion of the Morrow lying 

below the coal-bearing shale very little is known. However, a small lot of specimens embracing Lepidodendron 

stems, for the most part in spongy sandstone with soft 

iron residues filling the cavities left by the macerated 

plants, was collected by H. D. Miser and now rests 

among the Geological Survey collections of fossil 

plants. No distinct leaf scars showing nerve traces and 

appendages remain. Even the outlines of the bolsters 

are obscure in some of the specimens. Their superficial 

features, however, associate these Lepidodendron stems 

with L. aculeatum, the comprehensive L. veltheimianum, 

the L. obovatum group, and possibly L. jaraczewskii. 

There is also present a single fragment apparently 

definitely referable to Archaeocalamites scrobiculatus 

as its characters are in close agreement with those of 

the form with sharply cut nodes and continuous ribs 

described as Archaeocalamites transitionis. The paleobotanic evidence is insufficient for a definite correlation, but it justifies the tentative assumption that the 

Hale formation is of basal Westphalian, if not, in fact, 

Namurian age.

ENVIRONMENT OF THE WEDINGTON FLORA

As to the environment in which the Wedington 

flora lived, little that is definite can be noted. The 

composition and distribution of the members of the 

Morrow group (Pennsylvanian), which succeeds the 

Pitkin limestone, suggest a nearly baseleveled Ozarkia, 

along the south flank of which were a series of shoalwater deposits that at times, at least, may have been 

barrier-lagoonal in nature. Scarcity of conglomeratic 

material negatives any considerable elevation of the 

northern land, which, as indicated by the relative 

freshness of the plant remains buried in the sandstone, 

must have been comparatively near.

Apparently most of the plants drifting into the shallow water of the Wedington sandstone environment 

were small; the calamarian stems were all small, the 

lepidophytes include very few impressions of large 

stems, no large stem referable to fern or pteriodosperm 

is present, and no Cordaites leaves have been detected.

As will be noted in the descriptions, the cuticles of 

most of the ferns and fernlike plants are rugose, and 

many of them are provided with spines or short bristlelike hairs, some scattered sparsely and some relatively 

closely on both pinnules and rachises, even of small and 

relatively delicate fronds. The leaf bases of most of 

the lepidophytes are very highly protuberant, in some 

specimens almost extraordinarily so. Furthermore, 

the outer covering of these plants was rather distinctly

horny as well as rigid. The branches of Lepidodendron 

henbesti were slender and crooked, and near the ends 

the branchlets were so close (less than 2.5 centimeters 

apart) as to suggest a tangled or matted yet rather 

rigid growth. The seeds classed as Rhynchogonium 

are provided with an extension of the outer integument 

in a group of narrow acute teeth, suggesting a closed 

calyx, but the inner and thicker testa is cut in short 

blunt teeth, which appear to have rolled outward at the 

time of maturity of the seed, when also the calyx 

opened, presumably to permit fertilization, after which 

the calyx seems to have closed, as, very likely, also did 

the teeth guarding the opening to the pollen chamber 

of the seed. It is perhaps noteworthy that the cones 

described as Chlamidostachys bore broad winged bracts, 

along which the sporangiophores were distributed, 

and that by means of these wings and the hoodlike 

expansion of the terminal portion of the bract the 

fructifications seem to have been tightly wrapped and 

protected.

Though practically nothing is known of the internal 

structure of the plants, the inference may be drawn that 

the environment was not wholly favorable to the development of large size in growth of plants and trees 

and that the climate was probably marked by a seasonal 

deficiency of rainfall. Such a conclusion appears to 

harmonize with the occurrence of hardened and wellrounded pebbles of clay and fine-grained silt, mingled 

with the plants in the sandstone, and with the slightly 

gypseous content of the enveloping Fayetteville shale.

DESCRIPTIONS OF THE SPECIES

Genus ADIANTITES Schimper, emended, 1869

In connection with my description 15 of the seed 

Wardia, borne on certain fernlike fronds from the 

lower Pottsville of southern West Virginia, I applied 

the name Aneimites (Dawson) Schimper to these fronds 

as the generic name properly applicable, the name 

Adiantites, by which similar fronds had most frequently been designated, being then regarded as nomenclaturally untenable. For reasons that follow I 

discontinue this application of the name Aneimites 

in favor of Adiantites, the use of which, though on 

none too secure foundation, seems preferable to the 

coinage of a new generic name, otherwise necessary. 

Briefly, the essential points in the history of its use 

are as follows:

Adiantites was proposed by Goeppert 16 in 1836 to 

include 20 species, embracing chiefly ginkgoes, cyclopterids, and sphenopterids. Since that date all the 

species which in accordance with the accepted rules of 

nomenclature might be regarded as types of Goeppert's 

genus have been transferred to other genera. Meanis White, David, The seeds of Aneimites: Smithsonian Misc. Coll., vol. 47, pt. 3, 

no. 1550, p. 323, 1904.

16 Goeppert, H. R., Systema fllicum fossilium; Die fossilen FarrnkrSuter: Acad. 

Caesarea Leopoldino-Carolina Nova Acta, vol. 17, Suppl., p. 216, Breslau, 1836.
18 SHORTER CONTRIBUTIONS TO GENERAL GEOLOGY, 1936

while Schimper,17 in 1869, proposed the genus Adiantides Schimper " (Adiantites auct.)", to which he 

referred either directly or as synonyms the species 

enumerated by Goeppert in Goeppert's final group. 18 

Under the nomenclatural rules formerly followed by 

most paleobotanists the retention of Goeppert's term 

for this final residual, which included but four species, 

was permissible, without regard to generic type. 

Inasmuch as Schimper in his new genus gives type 

status to one of the species brought forward from 

Goeppert's list, his revision is here accepted. However, as the name Adiantides proposed as new by 

Schimper is evidently a mere modification of the spelling of the earlier name in a form that is not permissible 

under the rules followed by most paleontologists, the 

term Adiantites as spelled by Goeppert must be 

retained, though the restriction and definition of its 

conception and scope as emended by Schimper are 

recognized.

The subgeneric name Aneimites, proposed and 

long used by Dawson, 19 was made to embrace several 

species from the Upper Devonian, the Mississippian, 

and the Pottsville. However, Cyclopteris (Aneimites) 

acadica Dawson,20 from the lower Mississippian of 

Nova Scotia, first published in 1860 and more fully 

describe'd and illustrated in 1873,21 is shown to have a 

bifurcated petiole, and the inferior ultimate pinnules, 

which are short petiolate, are remarkably recurved 

in a way that is characteristic of the subgenus. As 

Cyclopteris (Aneimites) acadica had, in connection with 

the description of other plants by Dawson, been 

designated as the type of the subgenus Aneimites,22 

and as the mode of division of the frond of this species 

seems to differ generically from that of the fronds 

under consideration, from the upper Mississippian 

and lower Pottsville, the use of Aneimites for the 

latter is precluded, in spite of the elevation of the term 

to generic rank by Schimper M in 1874, with priority 

given to Dawson's type species.

So far as known, Aneimites, restricted to accord with 

the generic characters of Aneimites acadica, is confined 

to the lower Mississippian, whereas Adiantites is apparently confined to the upper Mississippian, where 

it is represented by the plant here described as Adian-

" Schimper, W. P., Traite de paleontologie veg6tale, tome 1, p. 424, I860. 

18 Goeppert, H. R., op. cit., p. 226; "c. Frons tripinnata."

" Dawson, J. W., On an undescribed fossil fern from the lower coal measures of 

Nova Scotia: Canadian Naturalist, vol. 5, p. 461,1860.

20 Dawson, J. W., On an undescribed fossil fern from the lower coal measures of 

Nova Scotia: Qeol. Soc. London Quart. Jour., vol. 17, p. 5, 1860; On the conditions 

of the deposition of coal, more especially as illustrated by the coal formation of Nova 

Scotia and New Brunswick: Idem, vol. 22, p. 153, pi. 8, fig. 32,1866.

21 Dawson, J. W., Report on the fossil plants of the Lower Carboniferous and 

Millstone Grit formations of Canada, p. 26, pi. 7, figs. 52-63, Canada Geol. Survey, 

1873.

» Dawson, J. W., The fossil plants of the Devonian and Upper Silurian formations of Canada, p. 48, Canada Qeol. Survey, 1871.

a Schimper, W. P., op. cit., tome 3, p. 489, 1874. Schimper gives first place to 

Aneimiies acadica (Dawson), which is followed by Aneimites adiantoides, of which 

Ettingshausen's Adiantum antiquum (Die fossile Flora des mahrisch-schlesischen 

Dachschiefers, p. 98, pi. 7, fig. 1,1865) is made a synonym.

tites minima, and to the Pottsville, where are found 

Adiantites jertilis and several other related species.

The genus Adiantites is typified in Goeppert's 

Adiantites cuneatus 2* which Schimper made a synonym of Brongniart's Sphenopteris nervosa,25 placing the 

latter at the head of the genus "Adiantides." Characteristic of the genus is the species described by Ettingshausen 26 as Adiantum antiquum, which was more elaborately illustrated by Stur 27 under the name Adiantides antiquus (Ettingshausen). The essential generic 

characters are as follows:

Fronds tri- or quadripinnate with slender rachis; primary 

divisions alternate, often very open; pinnules cuneate to cuneate-obovate, truncate or rounded at the apex or divided into 

two to five cuneate lobes, usually slightly pedicellate with 

narrow, relatively terete, and sometimes very narrowly margined 

rachis; nerves numerous, flabellately divergent, or with imperfect development of a principal nerve strand in the lower portion 

of the pinnule or lobe, the nervilles being generally slender, 

several times dichotomous, and straight or slightly curved.

Adiantites minima White, n. sp.

Plate 4, figure 38

Major divisions not seen; penultimate rachis strong, 

rigid, dorsally low-rounded, and lineate with distinctly 

decuning nerve strands descending from the ultimate 

pinnae; ultimate pinnae alternate, oblique, at an angle 

of abont 60°, close, slightly overlapping, small, linearlanceolate, slightly acute, with relatively broad, rigid 

or slightly flexuose, very narrowly alate axis; pinnules 

small, alternate, slightly decurrent, broadly cuneate 

to obovate, cuneate when sublobate, slightly broadpedicellate, oblique, slightly outward-curved, slightly 

obliquely round-truncate or broadly rounded at the 

apex, 3 or 4 millimeters long and 2 or 3 millimeters 

wide, the lobes, two or three in number, about 2.5 

millimeters long and 1 to 2 millimeters wide, somewhat 

divaricate; lamina thick, very minutely rugose, nearly 

flat, and decurrent in a narrow border along the 

rachis; nervation partly flabellate without the development of a strong primary nerve, the secondary nerves 

being derived at a wide angle in the decurrent base 

of the pinnule or near the base of each lobe, the 

nervilles being nearly straight and forking low in the 

lobe to furnish generally two or three nearly straight 

nervilles to the lobe.

This species is remarkable for the small size of its 

pinnules and lobes. The lobes, though relatively 

broad and robust as compared with those of other 

species of Adiantites, are in their arrangement, mode 

of development, and nervation characteristic of the

« Goeppert, H. R., op. cit., p. 226.

zs Brongniart, Adolphe, Histoire des v6g6taux fossiles, tome 1, p. 174, pi. 66, fig. 

2, 1828.

& Ettingshausen, C. von, Die fossile Flora des mahrisch-schlesischen Dachschiefers: K. Akad. Wiss. Wien, Math.-naturwiss. KL, Denkschr., Band 25, p. 22, 

pi. 7, fig. 1, 1865.

27 Stur, Dionysius, Die Culm-Flora: K.-k. geol. Reichsanstalt Abh., Band 8, Heft 

I, p. 66, pi. 16, figs. 4-6, pi. 17, figs. 3-4, 1875.
FOSSIL FLORA OF THE WEDINGTON SANDSTONE 19

genus. On account of their very small size, the plant 

is suggestive of portions of Sphenopteris divaricata or 

some of the relatively large and cuneately lobed pinnules referred by some authors to the Sphenopteris 

hoeninghausii group.

The general aspect of the narrowly alate rachis is 

shown in figure 38, plate 4, as are some of the aspects 

of the pinnules. Although the pinnules approximate 

in size some of those characteristic of Sphenopteris 

hoeninghausii, they are readily distinguished by the 

flat lamina and the more distinctly cuneate lobes.

Among the known species of Adiantites, A. minima 

appears most closely related to Adiantites fertilis,28 

to the smallest pinnae and pinnules of which the 

fragments in hand are strikingly similar. The Arkansas plant differs, however, in its shorter and relatively 

broader pinnules, which are thicker and in general 

rather more open. In the Pottsville plant, Adiantites 

fertilis, the leaf is thin and the nervation slender and 

relatively distant.

The fruit Wardia, found attached to Adiantites 

fertilis and generically in association with other species 

of the genus at other localities in the Pottsville group, 

has not yet been found in the Wedington. It will 

probably be discovered on further search. The genus 

is characteristic of and mainly confined to the Pottsville (Westphalian).

Locality: Bob Kidd Hollow, south of United States Highway 62, 3.2 miles southwest of Prairie Grove, Ark.; collected 

by H. D. Miser, L. G. Henbest, and David White, 1930 (U. S. 

Geological Survey lot 8075).

Type: U. S. Nat. Mus. 39477.

Genus CARDIOPTERIS Schimper, 1869 29 

Cardiopteris hirta White, n. sp.

Plate 4, figures 29, 31, 32, 33, 34, 35, 37

Pinnules relatively small, mostly about 11 millimeters 

in length, rounded, somewhat polymorphous, ranging 

from ovate or broadly oval to very broadly ovate or 

even slightly reniform, the younger ones generally 

longer than broad, the older frequently as broad or 

even broader than long, occasionally very faintly sublobate in one or two rounded and hardly differentiated 

lobes; lamina usually overlapping or clasping at the 

base, nearly flat, slightly arched at the border, rather 

thick, minutely rugose and provided with numerous 

stiff, relatively coarse hairs generally about 2 millimeters in length, for the most part oriented parallel to 

the nervation, which they partly obscure; nervation 

flabellate from the narrow point of attachment; nerves 

rather coarse, frequently striate, forking three to five 

times, according to the size of the pinnule, at a very 

narrow angle, while passing nearly straight or but 

slightly arching to the margin and approximately 

equidistant in all parts of the pinnule.

28 White, David, The seeds of Aneimites: Smithsonian Misc. Coll., vol. 47, pt. 

3, p. 323, pis. 47, 48, 1904.

» Schimper, W. P., Traite de paMontologie vSgStale, tome 1, p. 451,1869. 

72044—37———2

Most common among the small fragments and 

detached pinnules of ferns in the collection are relatively small isolated pinnules of a species of Cardiopteris, obviously related to Cardiopteris polymorpha 

(Goeppert) Schimper. The pinnules, which are generally rounded, rarely exceed 12 millimeters in length, 

and the smallest are less than 6 millimeters and scarcely 

more than 5 millimeters in breadth. All are characterized by the presence of short, stiff hairs, generally 

parallel to and even obscuring the nervation.

The most common and characteristic form of this 

species is seen in figure 35, plate 4, in which two clasping pinnules are probably not far from their original 

position. Another specimen, viewed dorsad and exhibiting the characteristic overlapping of the lobes, is 

shown in figure 32, plate 4, and the details of venation 

of a relatively large pinnule, slightly sublobate at the 

distal margin, are seen in figure 37.

Some relatively broad specimens of Cardiopteris 

hirta show slight sublobation, and two of the smallest 

pinnules are illustrated in figures 29, 33, and 34, plate 

4. No fragments of rachis to which pinnules are 

attached have been noted in the collection.

The rugosity and hairs characteristic of the species 

are shown in the enlargements, figures 31 and 37, 

plate 4, as is the nervation.

Cardiopteris hirta is closely related to Cardiopteris 

polymorpha (Goeppert) Schimper, though its pinnules 

are generally much smaller than those of C. polymorpha and are, in particular, distinguished by the 

broad striate nerves on which are superposed the short, 

stiff hairs.

The average pinnule of this species rather closely 

resembles the smallest of the pinnules figured by Stur 30 

from the Waldenburg series as Cardiopteris sp. It is, 

however, much smaller than the larger Waldenburg 

pinnules, which are much more broadly reniform and 

much larger.

The ordinary pinnules of Cardiopteris hirta are rather 

strikingly similar in size, form, and even in nervation 

to some of the pinnules described as Cardiopteridium 

spetsbergense by -Nathorst,31 though there is no evidence 

that the more distinctly cordate or cyclopterid pinnules 

from the Wedington were associated with much larger 

heteromorphous pinnules, rather broadly attached or 

even p etiolate and provided in some specimens with 

midribs, as was the case with the plant made by 

Nathorst the basis for his genus Cardiopteridium, which 

is found in the Mississippian of Spitsbergen.

Locality: Bob Kidd Hollow, south of United States Highway 

62, 3.2 miles southwest of Prairie Grove, Ark.; collected by 

H. D. Miser, L. G. Henbest, and David White, 1930 (U. S. 

Geological Survey lot 8075), and by H. D. Miser and C. B. 

Read, 1931 (U. S* Geological Survey lot 8264).

Types: U. S. Nat. Mus. 39478-39482.

30 Stur, Dionysius, Die Culm-Flora: K.-k. geol. Reichsanstalt Abh., Band 8 

Heft 2, p. 182, pi. 11, fig. 6,1877.

»i Nathorst, A. Q., Nachtr&ge zur pal&ozoisehen Flora Spitzbergens: Zur fossilen 

Flora der Polarlander, Teil 1, Lief. 4, p. 16, pi. 9 (see especially figs. 14 and 15),1914.
20 SHORTER CONTRIBUTIONS TO GENERAL GEOLOGY, 1936

Cardiopteris sp.

Plate 4, figures 40, 41

The small fragment shown in plate 4, figures 40 

and 41, is one of two specimens comprising portions of 

torn leaves that apparently represent a species of 

Cardiopteris in which the leaves are much larger than 

in Cardiopteris hirta, already described. In this form 

the pinnule, which is apparently slightly thinner than 

in the other species, has, as will be noted on comparing 

the figures, somewhat more distant nervation, which 

is less equidistant in the interior of the pinnule as compared to the marginal region. In this specimen leaf 

hairs do not seem to be present.

Locality: Bob Kidd Hollow, south of United States Highway 

62, 3.2 miles southwest of Prairie Grove, Ark.; collected by 

H. D. Miser and C. B. Read, 1931 (TJ. S. Geological Survey 

lot 8264).

Types: TJ. S. Nat. Mus. 39483.

Genus NEUROPTERIS (Brongniart) Sternberg, 1825 32 

Neuropteris sp.

Plate 4, figures 26, 27, 28

Among the small fragments of pinnae and the detached pinnules found in the collections are several 

that are apparently referable to the genus Neuropteris, 

though they are inadequate for satisfactory identification or specific description. Like the pinnules of the 

earlier representatives of this genus, they are broadly 

attached, and near the apex of the pinna or in the very 

young pinnules they are more or less confluent. A 

sublobate terminal pinnule is illustrated in figure 28, 

plate 4. Young pinnules broadly attached and probably decurrent have likewise been observed. The 

nervation of these pinnules is distinctly neuropterid, 

with generally well-developed median nerves, even 

where some of the nervilles, especially in the decurrent 

parts of the lamina, are derived from the rachis. The 

nerves are coarse and slightly irregular. They fork 

once or twice at rather wide angles while bending 

outward toward the margin, which they generally 

meet at an oblique angle. As is shown in the enlargement, figure 26, plate 4, the nervation is partially 

obscured by the presence of numerous short bristlelike 

hairs scattered over both the dorsal and ventral 

surfaces of the pinnule. These hairs are relatively 

large at the base, are stiff, and taper rather rapidly 

upward to a sharp point. They are about 1 or 1.25 

millimeters in length, and they generally lie parallel 

to the nervation, but occasionally their disposition is 

irregular.

The form represented by these specimens appears 

rather more rounded at the apex, and the pinnules 

are generally smaller than those in the material from 

the Mississippian of Europe figured as Neuropteris 

antecedens, though the larger of the fragments from the

*• Brongniart, Adolphe, Mus. histoire nat. Paris Mem., tome 8, p. 233,1822. Sternberg, Kaspar, Versuch emer geognostisch-botanischen Darstelluog der Flora der 

Vorwelt, Tentamen, p. xvil, 1825.

Wedington sandstone is in many respects comparable 

to one of the specimens figured by Stur in plate 15, 

figure 4, of "Die Culm-Flora." Neuropterid forms of 

the type illustrated by Ettingshausen 33 as Neuropteris 

heterophylla Brongniart and by Stur 34 as Neuropteris 

antecedens date far back in Mississippian time. Assuredly, however, not all the fronds illustrated by Stur 

as Neuropteris antecedens Stur can have belonged to a 

single species.

The Wedington plant is further characterized by the 

rigid bristlelike hairs borne on both surfaces of the 

lamina, which itself is coriaceous.

Though the pinnules agree in form with some of 

those of the Neuropteris pocahontas group in the 

lower Pottsville of the Appalachian trough, all differ 

from that group, which is not provided with hairs, by 

the much more distant, more broadly forking, and 

less strongly arched nervation. *

Locality: Bob Kidd Hollow, south of United States Highway 

62, 3.2 miles southwest of Prairie Grove, Ark.; collected by 

H. D. Miser, L. G. Henbest, and David White, 1930 (TJ. S. 

Geological Survey lot 8075), and by H. D. Miser and C. B. 

Read, 1931 (TJ. S. Geological Survey lot 8264).

Types: TJ. S. Nat. Mus. 39484, 39485.

Genus RHACOPTERIS Schimper, 1869 TM 

Rhacopteris sp.

Plate 4, figures 1, 6

A single specimen in the collection embracing portions only of three consecutive pinnules, shown in 

figure 1, plate 4, rather clearly represents a largepinnuled species of Rhacopteris. As seen in the illustration and enlarged photograph, figure 6, plate 4, 

the leaf is thick, even leathery, and granular-rugose. 

It is shallowly dissected in very oblique or nearly 

vertical lobes which turn slightly outward. The 

overlapping pinnules represented in this specimen 

were probably 2 centimeters or more in length and 

1.25 to 1.5 centimeters or more in width. The coarse, 

gently arching, and rather evenly curved nerves are 

in relief on both the dorsal and ventral surfaces. They 

are rather distant, nearly equidistant one from another, 

and they appear to fork three to five times at a narrow 

angle in passing from the midrib, which is not well 

developed in the upper part of the pinnule, to the 

apex of the lobe.

In the size and-indicated shape of the pinnules and 

both the texture and the nervation, this plant approaches very closely an undescribed species in the 

Mississippian of the Appalachian trough.

Locality: Bob Kidd Hollow, south of United States Highway 

62, 3.2 miles southwest of Prairie Grove, Ark.; collected by 

H. D. Miser and C. B. Read, 1931 (U. S. Geological Survey 

lot 8264).

Type: U. S. Nat. Mus. 39486.

33 Ettingshausen, C. von, Die fossile Flora des mahrisch-schlesischen Dachschiefers: 

K. Akad. Wiss. Wien, Math.-naturwiss. Kl., Denkschr., Band 25, p. 20, text fig. 4, 

pi. 6, fig. 1, 1865.

34 Stur, Dionysius, op. cit., Heft 1, pi. 15.

*• Schimper, W. P., Traitfi de palfiontologie v6getale, tome 1, p. 481, 1869.
FOSSIL FLORA OF THE WEDINGTON SANDSTONE 21

Genus RHODEA Fresl, 1838 3« 

Rhodea cf. R. subpetiolata (Potonie) Nfimejc

Plate 4, figures 2, 3

A few small fragments, one of which is photographically illustrated! in plate 4, figures 2 and 3, are, on 

account of the asymmetry of the pinnules, in which the 

inner basal lobes are longer and larger, referred with 

some doubt to the genus Rhodea. Though the pinnules 

are small and the lobes fewer, less truncate, and less 

unequal, they are slightly suggestive of Rhacopteris 

subpetiolata Potonie1 ,37 transferred by Nemejc 38 to 

Rhodea.

In some of the specimens the pinnules have a generally rhomboidal outline. The lobes are rather deeply 

dissected, narrowly wedge-shaped, and more or less 

obliquely rounded, with slight indication of truncation 

at the apex. The distal basal lobe appears broader, a 

little larger, and less oblique than the proximate lobe. 

The lamina is slightly arched ventrad and very narrowly decurrent along the upper portion of the outer 

rachis. The larger lobes are provided with median 

nerves, from which nearly straight nervilles pass at 

relatively oblique angles, forking once, whereas the 

narrow upper lobes appear to be provided with but a 

single nerve.

Though much smaller, the pinnules in the specimen 

illustrated are most suggestive of Rhodea subpetiolata 

(Potoni6), from the Waldenburg series and the coal 

basins of central Bohemia,38 with which the Arkansas 

plant may be associated pending the discovery of 

specimens adequate for its definite identification and 

description.

Superficially the Wedington specimens resemble the 

specimen illustrated by Feistmantel 39 in plate 15, 

figure 14, of his paper on the plants from the Carboniferous limestone at Rothwaltersdorf under the name 

Hymenophyllites furcatus Brongniart. The resemblance is, however, remote, if dependence is put on the 

enlarged figure 14a of the same plate as illustrating the 

detailed lobation and nerves.

Locality: Bob Kidd Hollow, south of United States Highway 

62, 3.2 miles southwest of Prairie Grove, Ark.; collected by H. D. 

Miser, L. G. Henbest, and David White, 1930 (U. S. Geological 

Survey lot 8075).

Types: Figured specimens, U. S. Nat. Mus. 39487

Rhodea cf. R. moravica (Ettingshausen) Stur

Plate 4, figures 19, 24, 25

The collection from the Wedington contains several 

very small fragments of a sphenopterid with small 

pinnules cut as if skeletonized in very narrow, delicate,

86 Presl, Karl, in Sternberg, Kaspar, op. cit, Hefte 7, 8, p. 109, 1838.

37 Potonie, H., Ueber einige Carbonfarne: K. preuss. geol. Landesanstalt Jahrb., 

1889, p. 26, 1892; Die floristische Qliederung des deutschen Carbon und Perm: K. 

preuss. geol. Landesanstalt Abh., neue Folge, Heft 21, p. 21, fig. 6, 1896.

& Nemejc, F., Rhodea subpetiolata Pot. sp., a new leaf type in the coal basins of 

central Bohemia: Acad. tcheque sci. Bull, internat., annee 28, pp. 56-61, pi. 1, text 

figs. 1, 2, 1927.

19 Feistmantel, Ottokar, Das Kohlenkalkvorkommen bei Rothwaltersdorf in der 

Qrafschaft Qlatz und dessen organische Einschliisse: Deutsche geol. Qesell. Zeitschr., 

Band 25, pp. 463-551,1873.

rather broadly divergent but somewhat irregular 

lobes, which may fork widely in linear, slightly flexuose 

subdivisions very nearly equaling in width the mother 

lobes. The very small specimen seen in figure 19, 

plate 4, illustrates these features. The material is 

insufficient for definite specific determination.

It is, however, perhaps specifically identical with 

some of the specimens figured by Ettingshausen 40 as 

Trichomanes moravicum Ettingshausen, which was 

transferred by Star 41 to the genus Rhodea.

The fragment with the more open lobes is very 

closely comparable to one of the specimens from the 

Moravian-Silesian roofing slates illustrated by Stur 42 

as Rhodea goepperti (Ettingshausen) sp. There is, 

however, nothing else in the collection which closely 

resembles other specimens described by Stur under 

the same name.

Locality: Bob Kidd Hollow, south of United States Highway 

62, 3.2 nfiles southwest of Prairie Grove, Ark.; collected by 

H. D. Miser and C. B. Read, 1931 (U. S. Geological Survey 

lot 8264).

Types: Figured specimens, U. S. Nat. Mus. 39488, 39489.

Genus SPHENOPTERIS (Brongniart) Sternberg, 1825 43 

Sphenopteris cf. S. communis Lesquereux

Plate 4, figure 9

A single fragment of Sphenopteris, which in its mode 

of ultimate subdivision and, to some extent, in the 

form and aspect of its connate, oblique, and but slightly 

dissected pinnules, which are ovately rounded at the 

top and slightly cuneate, rather closely resembles the 

plant from the Morrow group described by Lesquereux 

under the name Sphenopteris communis. The fragment is shown in figure 9, plate 4. Like the Morrow 

species, 'this one is somewhat rugose-villous, with 

partly masked, oblique, somewhat diffused, and relatively close nervation.

Further specimens are needed for the proper characterization and identification of this plant.

Locality: Bob Kidd Hollow, south of United States Highway 

62, 3.2 miles southwest of Prairie Grove, Ark.; collected by 

H. D. Miser, L. G. Henbest, and David White, 1930 (U. S. 

Geological Survey lot 8075).

Type: Figured specimen, U. S. Nat Mus. 39490.

Sphenopteris (Palmatopteris) erectiloba White, n. sp.

Plate 4, figures 10, 16

Ultimate divisions alternate, linear, very oblique, 

parallel, rigid, with dorsally terete, ventrally shallowly 

depressed, narrow, straight rachis; pinnules very 

oblique, nearly erect, lineate to very narrowly cuneate 

obovate, dissected in two to five narrow cuneate lobes,

40 Ettingshausen, C. von, Die fossile Flora des mahrisch-schlesischen Dach, 

schiefers: K. Akad. Wiss. Wien, Math.-naturwiss. KL, Denkschr., Band 25, p. 100- 

pl. 6, fig. 4, 1865.

41 Stur, Dionysius, Die Culm-Flora: K.-k. geol. Reichsanstalt Abh., Band 8, 

Heft 1, p. 42, pi. 11, fig. 7,1875.

v Idem, pi. 11, figs. 3-7.

« Brongniart, Adolphe, Mus. histoire nat. Paris Mem., tome 8, p. 233,1822. Sternberg, Kaspar, op. cit., Tentamen, p. xv, 1825.
22 SHORTER CONTRIBUTIONS TO GENERAL GEOLOGY, 1936

which in turn are very deeply dissected in the larger 

units, which are slightly arched ventrad, round obtuse 

at the apex, with lateral margins nearly parallel; 

lamina rather dense, minutely rugose, sparsely provided with rather slender short bristlelike hairs on the 

dorsal surface, and decurrent to form a very narrow 

bordering wing along the rachis.

Owing to the small size of the fragments here 

described, the mode of division of the frond and the 

satisfactory generic reference of the species are not at 

present determinable. The very oblique position, the 

close spacing, and the rigidity of the narrow pinnae 

are shown in figure 16, plate 4, which includes portions 

of two ultimate pinnae, extremely oblique and parallel, 

attached to a penultimate axis. The lobes are r.pparently rapidly dissected in the course of their development into narrowly cuneate lineate divisions, in which 

the lateral borders converge very slowly in passing 

downward. Bidentate lobes, in which the division is 

incipient, are relatively rare in the specimens.

The fragment here described deserves comparison 

with the forms referred by authors to Palmatopteris, 

including P.furcata. It is also comparable to the plant 

from the Westphalian series in the Durham coal field 

of England described by Kidston M as Rhodea eltringhami. Similar erectness of the lobes of the skeletonized 

sphenopterid is found in the Mississippian as well as the 

Pennsylvanian both in the Old World and in America.

Among the lower Pennsylvanian species to which 

the plant in hand may be compared, mention should be 

made of Sphenopteris ettingshauseni Stur?, some of 

whose pinnules are small, fasciculate, and erect, though 

generally less compact and broader.45

In general form and mode of development of the 

very oblique ultimate pinnae and the pinnules, the 

species in hand agrees with the older Mississippian 

sphenopterids. It is particularly comparable to 

Sphenopteris schimperiana Goeppert as illustrated by 

Vaffier,46 and it suggests comparison with some of the 

figures of forms from the upper Culm referred by 

Bureau 47 to Diplotrnema furcatum.

Locality: Bob Kidd Hollow, south of United States Highway 

62, 3.2 miles southwest of Prairie Grove, Ark.; collected by H. D. 

Miser and C. B. Read, 1931 (U. S. Geological Survey lot 8264).

Types: U. S. Nat. Mus. 39491.

Sphenopteris (Calymmatotheca) mississippiana White, n. sp.

Plate 4, figures 4, 5, 11, 13, 14, 15, 17, 18, 20, 21, 22, 23, 30,36, 39

Mode of primary division unobserved; main axis 

rigid and having a width of 1 centimeter or more, with

44 Kidston, Robert, Fossil plants of the Carboniferous rocks of Great Britain: 

Great Britain Geol. Survey Mem., Paleontology, vol. 2, pt. 3, p. 236, pi. 58, figs. 4,4a. 

4b, 1923.

« Stur, Dionysius, Die Culm-Flora: K.-k. geol. Reiehsanstalt Abb.., Band 8, 

Heft 1, p. 29, pi. 7, fig. 1, 1875. •

« Vaffier, A., Etude geologique et paleontologique du Carbonifere inferieur du 

Maeonnais: Univ. Lyon Annales, nouv. ser. 1, Sci. mfd., fase. 7, pi. 4, figs. 1, la, Ib, 

Ic; pi. 5, figs. 1, la, Ib, Ic, 1901.

*" Bureau, Edouard, Bassin houiller de la basse Loire, fase. 2, Description des flores 

fossiles, atlas, pi. 24 bis, figs. 1, 2, 3,1913. (In the series "Etudes des gites mingraux 

de la France.")

rather thick carbonaceous residue, in which Dictyoxylon 

structure is apparent; petioles lineate, with rather thick 

carbonaceous residue, the surface of which is provided 

with rather distant fairly strong though moderately 

slender spines; ultimate pinnae small, mostly rather 

short, generally with rather broad rachis, which is 

ventrally shallowly and broadly sulcate and lineate, 

dorsally rounded, and slightly flexuose in the upper 

portions; pinnules small, ovate-deltoid to oval-ovate 

and oval-deltoid, very open, slightly pedicellate, generally close, alternate, nearly touching or slightly overlapping, shallowly cut in three to five or six divaricate 

lobes, which become broadly cuneate or slightly squarrose, truncated, or very shallowly sinused at the apices, 

some of which are creased or slightly reflexed, and 

slightly acute at the distal angle; lamina thick, faintly 

rugose, frequently depressed ventrally just within the 

border of the lobes, as if fertile, slightly inflated ventrad, very narrowly decurrent along the rachis in the 

ultimate divisions, and sparsely provided with short 

bristlelike spines situated on low round protuberances; 

nervation rather coarse and forking at a wide angle 

to provide a nerville for each lobe or tooth.

The thin deposits of shale interbedded with the 

Wedington sandstone contain rather numerous very 

small fragments of a Sphenopteris whose close relationship to the Sphenopteris (Calymmatotheca} hoeninghausii group is shown not only by the form and 

arrangement of the ultimate pinnae and the pinnules 

but by the associated impressions of Dictyoxylon stems 

and the carbonized remains or the impressions of 

fragments of petiole sparsely clothed with small slender 

thornlike spicules of the type found on S. hoeninghausii. 

All the frond fragments are very small, and none of 

them show the mode of primary division of the frond; 

but nevertheless their number and characters are such 

as to admit not only specific description but the confident consideration of the species as representing an 

early form of the Lyginopteris type of frond in this very 

late Mississippian deposit. The Lyginopteris (Dictyoxylon) type is found also in a species from the Carboniferous limestone (upper Mississippian) from Kothwaltersdorf, in Glatz, referred in 1873 "to Sphenopteris 

hoeninghausii by Feistmantel.48

Fragments illustrating the ordinary size of the ultimate pinnae and the relations and lobation of the 

pinnules in the middle or lower portions of the frond 

are shown in figures 13 and 17, plate 4. The photographic enlargement of the former, figure 14, plate 4, 

shows both the pits left at the bases of the spicules on 

the ventral surface of the specimen, from which the 

epidermal residue has in part been scaled, and the depressions that have the appearance of sporangia, located immediately within the margin of the sharply 

depressed or creased ventral surface of the lamina. The

« Feistmantel, Ottokar, Das Kohlenkalkvorkommen bei Rothwaltersdori in der, 

Grafschaft Glatz und dessen organisehe Einschliisse: Deutsche geol. Gesell. Zeitschr. 

Band 25, p. 504, pi. 14, figs. 7, 7a, 1873.
FOSSIL FLORA OF THE WEDINGTON SANDSTONE 23

small fragment, figure 22, plate 4, which apparently 

was borne in the lower part of a pinna, probably in the 

middle or basal portion of the frond, exhibits the largest 

pinnules observed in the collection. In this as in other 

specimens the locations of the bases of the short spines 

that occur also on the midrib and on the rachis, as well 

as the decurrent lamina, are visible.

The fragment seen in figure 30, plate 4, in which the 

pinnules are more elongated, is probably derived from 

the upper part of the frond. On account of the less 

truncate lobation, which is not so distinctly divaricate 

and distant in this specimen, there is some room for 

question as to its specific identity with the others figured. The rachis is, however, distinctly spinose. The 

lamina is marked by the bases of the minute spicules 

or spines, and indications of developing squarrose lobation may be seen. The fragment shown in figure 20, 

plate 4, representing a small apical portion of an ultimate pinna from the lower part of the frond, in dorsal 

view, illustrates the relatively minute size of the pinnules and their lobation, which will at once be recognized as characteristic of the early Sphenopteris hoeninghausii group. The midrib, somewhat flexuose, is 

seen in dorsal relief.

A rather elongated form of pinnule, agreeing with 

that in figure 30, plate 4, though very much smaller, 

is shown in figure 17, plate 4. These figures indicate 

the generally relatively small form and the comparatively delicate detail of lobation in this Mississippian 

form. The spicular bases and the impressions of 

several of the flattened spicules, which in comparison 

with the very small pinnule are relatively large, may be 

observed in the photographic enlargement, four times 

natural size, figure 21, plate 4.

A rather indistinct cluster of what appear to be 

sporangia, apparently of the Calymmatotheca type, is 

shown magnified four times in figure 15, plate 4. It has 

the aspect of rather compactly though irregularly 

arranged sporangia grouped in a roundish glomerule 

that may be pedicellate. The reference of this specimen as possibly representing the polleniferous capsules 

of the species is tentative. Yet the frond described 

is unquestionably referable to Calymmatotheca.

Figure 4, plate 4, shows a part of an axis in which the 

dictyoxylon cortex is seen both in the impression and 

in the carbonized residue. The anastomosing strands 

shown in the enlargement, figure 5, plate 4, are strong, 

and the areas enclosed by the mesh vary in size, 

some of them being relatively large. Traces of the probably glandular and spicule-bearing protuberances are 

plainly visible near the centers of some of these areas.

In form and general aspect the fragments in hand 

carrying the small pinnules are similar to some of the 

ultimate pinnae described by Gothan 49 as Lyginopteris

49 Gothan, Walther, Die Steinkohlenflora der westlichen paralischen Carbonreviere Deutschlands: Inst. Palflobotanik u. PetrograpMe der Brennsteine Arbeiten, 

Band 1, Heft 2, p. 72, pi. 21, fig. 1, Preuss. geol. Landesanstalt, 1931; Die oberschlesische Steinkohlenflora, Teil 1, Farne und farnahnliche Gewachse: K. preuss. geol. 

Landesanstalt Abh., neue Folge, Heft 75, pi. 13, fig. 1,1913.

hoeninghausii, but the pinnae in the Wedington form 

are more compactly placed and more fully lobate, notwithstanding their small size.

The average pinna of this species somewhat resembles 

in size and even in shape one of the fragments from the 

Waldenburg beds originally figured by Stur as Calymmatotheca stangeri Stur.50

Localities: Bob Kidd Hollow, south of United States Highway 

62, 3.2 miles southwest of Prairie Grove, Ark.; collected by H. D. 

Miser, L. G. Henbest, and David White, 1930 (U. S. Geological 

Survey lot 8075), and by H. D. Miser and C. B. Read, 1931 

(U. S. Geological Survey lot 8264). About 2 miles southwest of 

Prairie Grove, Ark.; collected by H. D. Miser, L. G. Henbest, 

and David White, 1930 (U. S. Geological Survey lot 8145).

Types: U. S. Nat. Mus. 39492-39500.

Sphenopteris cf. S. obtusiloba Brongniart, 1829 «

Plate 4, figure 12

Among the forms of Sphenopteris represented by 

small fragments, too incomplete for identification and 

description, are two small sections of ultimate pinnae, 

one of which is illustrated in figure 12, plate 4.

The nervation of the pinnules is mainly derived from 

a primary nerve that is relatively strong, especially 

toward the base of the pinnule. The nervilles fork two 

or three times, while arching more or less, in passing 

from the midrib or the base of the pinnule to the 

border.

As to the inclusion of this form in the group represented by Sphenopteris obtusiloba or Sphenopteris 

trifoliata, there is little room for doubt. The largest 

pinnule is rather distinctly subtrilobate. The fragment shown in figure 12, plate 4, accords with the more 

distal pinnules or those in the upper part of the ultimate pinnae of the above-mentioned group. Obviously, 

however, the fragments are not definitely referable to 

either of the above-named species.

In some respects the figured specimens are somewhat 

comparable with the specimens from the MoravianSilesian slates described by Stur 52 as Sphenopteris 

Joliolata, which is, however, rather more like an extremely lax phase of Sphenopteris obtusiloba, though it 

clearly is not referable to that species. In the Silesian 

material the pinnules are more nearly reniform and are 

more crowded and less decurrent.

The fragment illustrated is superficially comparable 

also to that figured by Bureau from the upper Culm of 

the basin of the lower Loire 53 as Sphenopteridium 

dissectum Schimper.

Locality: Bob Kidd Hollow, south of United States Highway 

62, 3.2 miles southwest of Prairie Grove, Ark.; collected by H. D. 

Miser, L. G. Henbest, and David White, 1930 (U. S. Geological 

Survey lot 8075).

Type: Figured specimen, U. S. Nat. Mus. 39501.

so Stur, Dionysius, op. cit., Heft 2, p. 155, pi. 9, fig. 4,1877. 

H Brongniart, Adolphe, Histoire des vegetaux fossiles, tome 1, p. 204,1829. 

82 Stur, Dionysius, Die Culm-Flora: K.-k. geol. Reichsanstalt Abh., Band 8, Heft 

1, p. 22, pi. 5, figs. 3-5, 1875. 

«3 Bureau, Edouard, Bassin houiller de la basse Loire, fasc. 2, atlas, pi. 7, fig. 3,1913.
24 SHORTER CONTRIBUTIONS TO GENERAL GEOLOGY, 1936

Sphenopteris cf. S. schimperiana Goeppert M 

Plate 4, figures 7, 8

A few small fragments, one of which is illustrated in 

figures 7 and 8, plate 4, though insufficient for reliable 

determination, offer such distinctive characters as to 

deserve illustration, in the hope that publication may 

lead to the discovery of more complete specimens. As 

shown in figure 7, one fragment shows a detached pinnule or possibly merely a lobe of a pinnule, fasciculate 

in type, in which the lobes, whose collective profile is 

rounded, are rather deeply cut, closely placed, cuneate 

in position, relatively rounded at the apex, and almost 

equally wide in all parts. The carbonaceous residue, 

a portion of which remains, is thick and slightly rugose, 

and the nerves fork at a rather narrow angle.

On account of the very close resemblance of the 

fragments described above to the details of the plant 

figured by Feistmantel 55 as Hymenophyllites schimperianus from the Carboniferous limestone at Rothwaltersdorf, in Silesia, I tentatively place them under 

that specific name, though the agreement with the 

descriptions and figures published by Goeppert M and 

Schimper 56 is more remote.

Locality: Bob Kidd Hollow, south of United States Highway 

62, 3.2 miles southwest of Prairie Grove, Ark.; collected by 

H. D. Miser and C. B. Read, 1931 (U. S. Geological Survey 

lot 8264).

Type: Figured specimen, U. S. Nat. Mus. 39502.

Genus TELANGIUM Benson, 1904 " 

Telangium? sp.

Plate 5, figure 2

Under the reference cited above is photographically 

illustrated what appears to have been a loose glomerule 

of fusiform, acutely tapering sacs. The single specimen in hand was evidently macerated, and the resulting hollows in the sand are filled with sand grains and 

loose limomtic powder. At the bottom and toward 

the upper border of the mold are seen the impressions 

of portions of clawlike appendages, which I interpret 

as probably sporangial. The inner surfaces of these 

sporangia (?) are relatively smooth. There is no 

trace of a median nerve or other vascular tissue in the 

sporangial impressions.

The small fragment in hand is probably referable 

to the genus Telangium, though it is rather closely 

comparable to some of the specimens described as 

Calymmatotheca. The example illustrated deserves 

comparison especially with Telangium qffine (Lindley

s* Goeppert, H. R., Ueber die fossile Flora der Silurischen, der Devonischen und 

unteren Kohlenformation oder des sogenannten Uebergangsgebirges: Acad. Caesarea 

Leopoldino-Carolina Nova Acta, vol. 27, p. 66, pi. 37, figs. 2a, 2b, 1859.

M Feistmantel, Ottokar, Das Kohlenkalkvorkommen bei Rothwaltersdorf in der 

Grafschaft Glatz und dessen organische Einschliisse: Deutsche geol. Gesell. Zeitschr., 

Band 25, p. 513, pi. 15, figs. 13, 13a, 1873.

" Schimper, W. P., Les vfigfitaux fossiles, in Koechlin-Schlumberger, 3., and 

Schimper, W. P., Le terrain de transition des Vosges, p. 341, pi. 29,1862.

" Benson, Margaret, Telangium scotti, a new species of Telangium (Calymmatotheca') showing structure: Annals of Botany, vol. 18, p. 162,1904.

and Hutton) Benson as illustrated by Kidston 58 

from the oil shale group of the Calciferous Sandstone 

series of Scotland.

Locality: Bob Kidd Hollow, south of United States Highway 

62, 3.2 miles southwest of Prairie Grove, Ark.; collected by 

H. D. Miser, L. G. Henbest, and David White in 1930 (U. S. 

Geological Survey lot 8075).

Type: Figured specimen, U. S. Nat. Mus. 39503.

'Genus RHYNCHOGONIUM Heer, 1876 TM

The seeds described below as Rhynchogonium 

fayettevillense are apparently indistinguishable generically both from those illustrated and described by 

Heer from the Mississippian of Spitsbergen as Rhynchogonium and specifically as R. crassirostre and R. 

costatum, on the one hand, and that described by 

Zalessky 60 from the Mississippian Msta stage of 

northern Russia under the name Boroviczia, on the 

other. Though admitting the very close similarity in 

characters and the obvious relationship of his genus to 

that much earlier described by Heer, Zalessky concluded, though not without doubt, that the Russian 

form was probably of true generic rank, by virtue of 

the apparently more elaborate integuments. Subsequently, however, Nathorst,61 after reexamination 

and redescription of Rhynchogonium and close comparison of the Spitsbergen seed with Boroviczia, rejected the structural distinction and concluded that 

the genera were extremely closely related, but that 

they might, however, be usefully separated by reason 

of the prolonged beak, which is more sharply differentiated in Rhynchogonium than in Boroviczia. He 

also uses the name Boroviczia for two species of seeds 

from Spitsbergen.

As will be seen in the description of Rhychogonium 

fayettevillense, its form, though comparable to that of 

Rhynchogonium costatum Heer, is intermediate between 

R. costatum and the ovate Boroviczia karpinskii. In 

the Wedington seed the lobes or segments marked by 

longitudinal costae prevailingly number 10 instead of 

8, as in the Arctic seed. The free lobes forming what 

Zalessky described as the "calyx" appear to be an 

extension of the outer vascular integument, which 

below the point of union of the teeth or lobes may 

be coherent with the very thick inner testa.

Boroviczia is represented by a species found in the 

upper Pottsville at Campbells Ledge, near Pittston, Pa., 

and in my judgment it is also distinctly congeneric 

with the fruits described by Lindley and Hutton 62 as 

Carpolithus sulcatus, which was referred by Kidston to

s8 Kidston, Robert, Memoir on the fossil plants of the Carboniferous rocks: Great 

Britain Geol. Survey Mem., Paleontology, vol. 2, pt. 5, p. 446, pi. 101, figs. 1, 5,1924. 

56 Heer, Oswald, Flora fossilis arctica, vol. 4, Abt. 1, p. 19, 1876.

60 Zalessky, M. D., Uber Friichte aus den Untercarbon-Ablagerungen des Msta, 

beckons in Nord-Russland: Acad. imp. sci. St.-Petersbourg Bull., tome 22, no. 3- 

p. 115, 1905. (See Boroviczia karpinskii, p. 114, figs. 1-9.)

61 Nathorst, A. G., Nachtrage zur palSozoischen Flora Spitzbergens: Zur fossilen 

Flora der Polarlander, Toil 1, Lief 4, p. 22,1914.

M Lindley, John, and Hutton, William, Fossil flora of Great Britain, vol. 3, pi. 

220, 1837.
FOSSIL FLORA OF THE WEDINGTON SANDSTONE 25

the genus Rhynchogonium.® To the same genus, 

further, is to be referred a specimen in the Lacoe 

collection, in the United States National Museum, 

representing Trigonocarpum ellipticum Goeppert, from 

the Carboniferous limestone of Rothwaltersdorf, in 

Silesia.

From the examination of the specimens in hand, 

there appears to be no adequate basis for the generic 

distinction between Boroviczia, and the earlier established genus Rhynchogonium, to which in the following 

pages I have given precedence.

Rhynchogonium fayettevillense White, n. sp.

Plate 8, figures 1-8, 12-14, 22

Seeds ovate-oval to ovate-triangular in longitudinal 

profile, 11 to 18 millimeters in length, 4 to 11 millimeters in width, round at the bottom, apiculate to 

tapering-acute at the top, with broad chalaza, above 

which originate 6 to 12 nearly equal ribs, which become 

sharper and crested or narrowly alate in passing upward, 

the intervening areas or segments being slightly concave, especially near the ribs, parted near the top in 

tapering narrow lobes, which may converge, though 

distinct, to a sharp point or which may be slightly 

reflexed or flared in a short funicular neck; outer 

surface rather finely and somewhat irregularly striate; 

inner surface of outer testa very finely striate with the 

rows of minute punctations, which are slightly elongated 

in the longitudinal direction.

The seeds here described occur in great numbers in 

portions of the plant-bearing Wedington sandstone, 

where they appear to have accumulated in pockets in 

the rapidly deposited sand. They differ greatly in 

size, as may be seen by a glance at the photographs, 

but in spite of these considerable differences I am 

disposed to regard most of them as belonging to a 

single species, in which many of the specimens are 

presumably very young. The small specimens seem 

to have been more easily compressed than the large 

ones, but I observe no specific character other than 

size in accordance with which they may be differentiated, and in the matter of size the gradational sequence appears to be complete.

Several seeds of average dimension are shown in a 

group in figure 2, plate 8. The larger specimens in 

this group are of the average dimension. Figure 7, 

plate 8, illustrates the comparatively large chalaza. 

Figure 3, plate 8, shows a large and apparently mature 

specimen in which the overlobes of the segments of the 

outer testa are converged to a point and prolonged 

with considerable delicacy. This specimen represents 

the extreme length of the tapering lobes. The free 

ends of the lobes of the outer integument, some of 

which appear short and blunt, as if shriveled or possibly

« Zalessky, M. D., op. cit., p. 120.

rolled backward somewhat, are seen in figures 1 and 

13, plate 8.

In several of the specimens, especially those of smaller 

size, the fruit is rather indistinctly, or rarely distinctly, 

triangular. However, the dominance of three primary 

ribs is nearly always lost in passing upward, so that 

the angles, usually 7 to 10 in number, are nearly equal 

in prominence. The crest simulates a wing but thickens rapidly backward from the edge. None of the seeds 

are attached to any fragment of stem or rachis. The 

relations of the seed to any one of the pteridospermatic 

types present in the flora is a matter of speculation. 

All but a small number of the specimens are in sandstone, and of these none are flattened, though many of 

them are somewhat deformed under pressure. Evidence as to the internal structure is lacking. However, 

from the aspect of the free upper portions of the segments of the outer test, it appears rather probable that 

the pollenic chamber was large, that the micropylar 

neck was relatively soft and nonresistant, and that the 

apices of the lobes, which flare outward in most of the 

specimens, may have turned upward and inward, 

covering, if not closing, the micropylar canal in the 

mature specimens after fructification. In fact, I am 

slightly inclined to believe that the free upper portions 

of the outer envelope may have opened and flared 

distinctly outward only at maturity of the ovule.

The seeds, though representing the old form genus 

Rhabdocarpos Goeppert and Berger, are possibly related 

to Hexapterospermum Brongniart or possibly even to 

Lagenostoma Williamson.

The seed from the Wedington is very closely related 

in its characters to that described by Goeppert as 

Trigonocarpum ellipticum, especially as that species is 

exemplified in the Lacoe collection of the United States 

National Museum by a specimen (no. 26795) from 

Rothwaltersdorf, in Silesia. The European form is, 

however, almost exactly oval and is less distinctly 

ribbed.

Congeneric with the plant described, above and 

rather closely related to it, though considerably larger, 

is the fruit from the upper Pottsville at Campbells 

Ledge, near Pittston, Pa., described by Lesquereux 64 

as Carpolithus cistula. The Wedington form agrees in 

size as well as other characters rather more closely 

with specimens collected near Colinton, near Edinburgh, Scotland, and presumably from the Calciferous 

Sandstone series, identified by Kidston, who transmitted the specimens to the Lacoe collection, now in 

the United States National Museum (nos. 26465, 

26466, 26467, and 26469) as Carpolithus sulcatus Lindley 

and Hutton. The Wedington seed should also be compared with that from the lower Carboniferous of Scot64 Lesquereux, Leo, Description of the coal flora of the Carboniferous formation in 

Pennsylvania and throughout the United States: Pennsylvania 2d Qeol. Survey 

Kept. P, vol. 2, p. 595, 1880.
26 SHORTER CONTRIBUTIONS TO GENERAL GEOLOGY, 1936

land described by John Walton as Holcospermum 

ellipsoideum, whose generic identity with Rhynchogonium, as suggested by Walton,65 is hardly to be doubted. 

To the genus Bhynchogonium should also be referred 

the fruit described by Bureau 66 as a sporangium of 

Lepidophloios laricinus Sternberg. The cleft calyxlike 

beak of the plant from the upper Culm of the basin 

of the lower Loire is plainly shown in Bureau's figure, 

which in form resembles Zalessky's Boroviczia, though 

in size the fruit closely resembles Rhynchogonium 

cistula (Lesquereux).

Localities: Bob Kidd Hollow, south of United States Highway 62, 3.2 miles southwest of Prairie Grove, Ark.; collected 

by H. D. Miser, L. G. Henbest, and David White, 1930 (U. S. 

Geological Survey lots 8075, 8140), and by H. D. Miser and 

C. B. Read, 1931 (U. S. Geological Survey lot 8264). About 

2 miles southwest of Prairie Grove, Ark.; collected by H. D. 

Miser, L. G. Henbest, and David White, 1930 (U. S. Geological 

Survey lot 8145).

Types: U. S. Nat. Mus. 39504-39513.

Genus CARPOUTHUS Linnaeus, 1768 

Carpolithus inquirenda White, n. sp.

Plate 8, figures 9, 10, 15

Seeds very small, ovate-round, 3 to 3.5 millimeters 

long and 2.5 to 3 millimeters wide, rounded at the base, 

slightly apiculate with rather thick envelope, which is 

sclerotic with radiating nerves at the base.

The fruit illustrated in figures 9, 10, and 15, plate 8, 

is represented by only two specimens in the collection. 

It might readily be mistaken for a small sporangium 

except for the fact that, as indicated in the photograph, plate 8, figure 9, the integumental residue is 

relatively thick and apparently thickest at the base, 

which is marked by rather strong, though not very 

distinct, longitudinal radial nervation. Further, the 

apex of the fruit is slightly apiculate. The specimen 

shown in figure 9, plate 8, is partly split longitudinally at the apex. That seen in figure 15, plate 8, 

is similarly beaked at the top and flattened at the base. 

There is, therefore, little room for doubt that the fruit 

is a seed.

The fruit here described is extremely close to those 

described by Lesquereux under the name Carpolithes 

perpusillus, from Campbells Ledge, Pa., and by 

Lindley and Hutton as Carpolithes ovoideus as identified 

by Lesquereux in English material. The specimens 

from Pennsylvania are generally somewhat smaller 

than the Wedington form, but the British specimens 

are distinctly larger, though strikingly similar.

Locality: Bob Kidd Hollow, south of United States Highway 62, 3.2 miles southwest of Prairie Grove, Ark.; collected by 

H. D. Miser and C. B. Read, 1931 (U. S. Geological Survey 

lot 8264).

Types: U. S. Nat. Mus. 39515, 39516.

65 Walton, John, Contributions to the knowledge of lower Carboniferous plants, 

pt. 3: Eoyal Soc. London Philos. Trans., ser. B, vol. 219, p. 368, pi. 26, figs. 40, 40a, 

Sept. 9,1931. __

68 Bureau, Edouard, Bassin houiller de la basse Loire, fasc. 2, Description des 

flores fossiles, atlas, pi. 74, fig. 6,1913. (In the series "Etudes des gltes mine'raux de 

la France.")

Genus LEPIDODENDRON Sternberg, 1820 67 

Lepidodendron henbesti White, n. sp.

Plate 6, figures 1, 4^9

Stems and branches of rather small size, very 

ramose, branches irregular, often unequal, at angles of 

about 60°, the branchlets sometimes but 2.5 or 3 

centimeters apart in the small twigs and not in the same 

plane; leaf cushions broadly diamond-shaped, rhombic 

in the small twigs, with rather strongly protruding 

leaf scar, which is situated considerably below the 

transverse axis of the bolster and which is very narrowly 

separated from those on either side; leaf scar relatively 

high on leaf cushion, generally facing slightly distad in 

the smaller branches and usually appearing at the 

extreme upper apex in the flattened specimens, very 

broad, the lower border nearly straight or slightly 

round dentate at the medial line; lateral angles acute 

and but faintly decurrent, the lateral borders convex 

above the lateral angles and passing nearly straight, 

with very slight inward curvature, to the slight obtuse 

upper angle, which appears slightly notched around 

the ligular pit; nerve trace and lateral cicatricules 

small, close to the lower margin of the leaf scar, or 

placed one-third of the altitude of the leaf scar; leaf 

cushions broadly rounded below the leaf trace and 

generally rather faintly round carinate, the lateral 

fields being relatively flat or gently arched; lateral 

appendages generally rather faint, though sometimes 

well marked in the impressions, narrow, relatively 

long, and slightly convergent downward; ligular pit 

generally distinct and marked in the impressions by a 

protruding point inclined slightly downward close to* 

the apex of the scar.

The general aspect of the bolsters and leaf scars of 

this species is shown in figure 5, plate 6, which represents the partial width of a branch that appears to be 

of moderate size. Not all of the fragment is shown in 

the photograph. As is shown in the change in the 

direction of the bolsters, this fragment is branching 

at the top. Another branch is indicated at the extreme 

left about 4 centimeters below the top, and the base of 

yet another branch appears on the opposite side nearly; 

10 centimeters above the top of the fragment shown 

in the photograph. The stem is slightly zigzag, to 

correspond to the ramification. The frequency of 

division of the small branches of the species is well 

illustrated in figure 6, plate 6, and the counterpart, 

figure 9 of the same plate, which exhibits certain features not shown in the other specimen. In one of the 

smaller branches seen in the collection, divisions appear 

to have been at intervals of 2 to 3 centimeters.

The leaf trace, usually partially concealed in the 

somewhat compressed bolsters, is shown in figures 4 

and 5, plate 6. In portions of both these specimens 

the parichnoian appendages are indistinctly seen. In"

67 Sternberg, Kaspar, Vorsuch einer geognostisch-botanischen Darstellung d& 

Flora der Vorwelt, Heft 1, p. 23,1820.
FOSSIL FLORA OF THE WEDINGTON SANDSTONE 27

some of the partly flattened bolsters the impressions 

of the appendages are not only made to overlap a little 

on the lower border of the leaf scar, but some of them 

are continuous with the internal mold of the lateral 

cicatricules.

As shown in figure 5, plate 6, the leaf cushion is 

ordinarily nearly flat or slightly convex, with a very 

poorly defined, slightly rounded keel, which, where 

more distinct, owes its prominence to the impression of 

the vascular sheath as much as to any actual keel on 

the outer surface of the bolster. In the specimen shown 

in figure 5 the lower border of the leaf scar is nearly 

horizontal or but slightly round-dentate on the medial 

line. The impression of the orifice of the ligular pit 

seen in many of the bolsters overlaps behind the tip of 

the leaf scar, so as to produce the effect of notching 

the leaf scar. It is probable, however, that the uncompressed leaf scar is but slightly round-notched.at the 

apex.

The impressions of the cortical neural tracts dilate 

broadly downward, so that the leaf cushions appear 

to be divided into a downward-broadening median and 

two relatively short lateral fields, which adjoin the 

border of the leaf scars. This appearance is probably 

incidental to the condition of preservation and the 

collapse of the neural sheath. Some of the parichnoian 

appendages seem to coalesce with the border portions 

of the neural sheath.

The very broad or nearly square outline of the bolster 

impressions of the smaller branches is illustrated in 

figures 1, 6, 7, 8, and 9, plate 6. The aspect of the leaf 

scar and its relative proportions are shown in figure 1, 

which illustrates a small fragment of branch impression. 

This represents nearly the smallest of the branches of 

this species yet found in the collection.

The species described above is characterized by the 

rather distinctly diamond-shaped outline of the bolster, 

by the very broad deltoid leaf scars, the lower borders 

of which are nearly straight, by the relatively flat or 

but slightly round-carinate configuration of the area 

below the leaf scar, and by the rather elongated and 

faint appendages, which are not visible in all specimens. 

The irregular closely spaced branching, which lies in 

different planes, also appears characteristic.

At the type locality, about 2 miles southwest of 

Prairie Grove, only fragments of the impressions of 

stems or branches of relatively small diameter appear 

to represent this species. Pieces of several larger stems 

that might at first be referred to this form are on close 

inspection found to be faintly transversely corrugated 

across the broadly rounded lower portion of the bolster. 

I have therefore placed them with Lepidodendron 

wedingtonense, notwithstanding close similarities between the leaf scars, which in these forms are very 

strongly protuberant and suggest those of Lepidodendron henbesti. On the other hand, the typical Lepido72044—37———3

dendron wedingtonense is very distinctly corrugated 

both above and below the leaf scar. The collection of 

additional material may point the way to a different 

taxonomic association of these fragments with much 

larger, more strongly protruding, and in some specimens faintly corrugated leaf cushions.

In its frequency of branching and the very broadly 

rhombic or nearly squarrose impressions of the bolsters, 

Lepidodendron henbesti is comparable superficially with 

some of the impressions of small branches from the 

Allegheny formation of the Pennsylvanian, referred by 

Lesquereux to Lepidodendron dichotomum. That species 

differs saliently, however, by its distinctly carinate 

bolsters and by the more rhomboidal form of leaf scar.

Localities: Bob Kidd Hollow, south of United States Highway 

62, 3.2 miles southwest of Prairie Grove, Ark.; collected by 

H. D. Miser, L. G. Henbest, and David White, 1930 (U. S. 

Geological Survey lot 8140). About 2 miles southwest of 

Prairie Grove, Ark.; collected by H. D. Miser, L. G. Henbest, 

and David White, 1930 (U. S. Geological Survey lot 8145).

Types: U. S. Nat. Mus. 39514, 39517-39522.

Lepidodendron occidentale White, n. sp.

Plate 5, figures 5, 8

Bolsters in rows, alined nearly vertical and transverse; leaf cushions contiguous, broadly ovate, with 

rather clearly marked sinuate lateral boundary lines, 

distally, rather obliquely, and broadly round-truncate 

a very short distance above the leaf scar, nearly flat 

or in the lower part slightly higher along a rather broad 

medial zone, which is transversely corrugated but not 

carinate; leaf scar rather prominent, facing slightly 

upward with both distal and proximate borders arched, 

relatively straight on the sides and forming acute 

lateral angles, which bend slightly downward to define 

a roughly obovate area that includes the leaf scar and 

the lower fields; vertical diameter of leaf scar approximately two-thirds that of the transverse; medial scar 

large, a little above the middle of the leaf scar; lateral 

traces at the same level and a little distant; lateral 

appendages slightly elongated vertically and relatively broad; ligular pit large, a little above the 

obscurely and shallowly sinused upper angle of the 

leaf scar.

Several fragments in the collection (lot 8145) from 

the locality about 2 miles southwest of Prairie Grove, 

two of which are illustrated in figures 5 and 8, plate 5, 

represent this form, which evidently falls within the 

somewhat comprehensive group generally identified as 

Lepidodendron volkmannianum. The larger fragment 

(fig. 5) is not sufficient to prove that the alinement of 

the bolsters is at once vertical and transverse, though 

assuredly it approaches close to those directions. The 

traces in the leaf scar are nearly midway of its height 

and are alined slightly above the lateral angles. In 

other words, the upper and lower halves of the leaf 

scar are hardly symmetrical, though they at first suggest
28 SHORTER CONTRIBUTIONS TO GENERAL GEOLOGY, 1936

symmetry. The generally round, sometimes even 

slightly indented upper border that appears to be 

characteristic of Lepidodendron volkmannianum Sternberg is not seen in the two specimens in this collection. 

On the impressions of several of the bolsters slightly 

elongated shallow depressions extending downward 

short distances from the upper borders of the field offset 

the lateral cicatricules and offer slightly questionable 

evidence of the presence of the lateral parichnoian 

appendages. On all the fragments in hand the transverse corrugation is mainly confined to the broad 

medial zone of the leaf cushion.

On account of the obviously close relationship of the 

Wedington tree to the Old World type of Lepidodendron 

volkmannianum Sternberg, I was at first disposed to 

refer it tentatively to that species. However, inspection of the original figure given by Volkmann,68 together 

with the descriptions and illustrations of the European 

type as given by Sternberg,69 the founder of the species, 

Presl,70 Stur,71 and others, shows that the tree from the 

Wedington sandstone differs from the European type 

in such significant respects as to prohibit its inclusion 

under the same name. As figured both by Volkmann 

and by Sternberg, the European plant is much shorter 

in the vertical diameter of its leaf scar, and the upper 

angle of the leaf scar is very much more rounded, so as 

to produce a curved profile, in alinement with which 

the lateral angles are somewhat extended. In the 

Wedington trunk, on the contrary, the distal angle is 

well developed, the vertical diameter is much longer in 

proportion, and the lateral angles not so prolonged. 

However, the European type as shown by Volkmann 

and Sternberg is transversely corrugated along a 

relatively narrow median zone, almost exactly as in 

the specimens here described.

The Old World species as generally described and 

figured appears to be present in the Chester group of 

the Eastern Interior basin and in the beds of Chester 

age in the Appalachian trough. Specimens with vertically short leaf scars apparently conforming to the 

European type are figured by No6 72 from the Chester 

group near Princeton, in western Kentucky.

The material from Kentucky deserves comparison 

with the fragments figured by Stur 73 as Lepidodendron 

volkmannianum from the Waldenburg series. The 

lateral appendages seem to be lacking in the European 

material representing the L. volkmannianum as generally illustrated, but points which are possibly construable as lateral appendages may be observed in 

Stur's plate 40, figure 2.

M Volkmann, G. A., Silesia subterranea, pi. 15, fig. 4, Leipzig, 1720.

68 Sternberg, Kaspar, Versuch einer geognostisch-botanischen Darstellung der 

Flora der Vorwelt, Tentamen, p. x, pi. 53, figs. 3a, 3d, 1825.

" Presl, Karl, in Sternberg, Kaspar, op. cit., Hefte 7, 8, p. 179, pi. 68, fig. 8,1838.

" Stur, Dionysius, Die Culm-Flora: K.-k. geol. Eeichsanstalt Abh., Band 8, 

Heft 2, p. 286, pi. 18, fig. 4; pi. 23, figs. 2-5,1877.

» Noe, Adolf, The flora of the western Kentucky coal field, in Weller, Stuart, 

Geology of the Princeton quadrangle: Kentucky Geol. Survey, ser. 6, vol. 10, p. 129. 

fig. 2, p. 130, fig. 4, Frankfort, 1923.

w Stur, Dionysius, op. cit. (Die Culm-Flora), Heft 2, p. 288, pi. 18. (See fig. 4.)

The species from Arkansas differs but little from that 

figured by Bureau 74 as Lepidodendron volkmannianum 

from the basin of the lower Loire, except that the latter 

has rather wider bolsters as well as somewhat shorter 

leaf scars.

A closely related species is that figured under the 

name Lepidodendron turbinatum Lesquereux.75

On account of the relatively large size of the leaf scar, 

the generally obovate configuration of the truncated 

bolster, and the relief of the leaf scar, the form in hand 

presents some superficial resemblance to the foreshortened bolsters of Lepidodendron clypeatum. That species differs, however, by the distinct keel, which is 

transversely notched, by the phyllotaxy, and by other 

features that are equally distinct though less conspicuous.

Locality: About 2 miles southwest of Prairie Grove, Ark.; 

collected by H. D. Miser, L. G. Henbest, and David White, 

1930 (U. S. Geological Survey lot 8145), and by H. D. Miser 

and C. B. Read, 1931 (U. S. Geological Survey lot 8266).

Types: U. S. Nat. Mus. 39523, 39524.

Lepidodendron purduei White, n. sp.

Plate 5, figure 9

Bolsters foliaceous, fusiform or narrowly acute, contiguous, very obliquely protruding, slightly overlapping, 

noncarinate, dorsally strongly and evenly rounded, 

slightly beaked at the summit at the point of emission 

of the nerve; leaves attached at the lateral margins 

around the upper third of the protruding cushion, 

slightly wider at the base than the bolster at the widest 

part, very oblique or nearly erect, about 5 millimeters 

wide and 2.5 centimeters long, tapering gently from a 

point abreast of the apex of the bolster to the acute 

tip, with wide medial nerve and apparently broadly and 

roundly sulcate ventrally toward the base; ligular pit 

distinct; appendages not observed.

A single fragment, shown in figure 9, plate 5, is the 

sole representative of what is apparently a very interesting species. The erosion of the specimen permits the observation of the impressions of the appressed 

and nearly erect leaves, both along the upper border of 

the fragment and near its base. The cortices of the 

cushions are apparently hard and rounded, except near 

the apex, which is slightly carinate; leaf scars are not 

clearly indicated, for the reason that the leaves are still 

attached to the extremely obliquely directed overlapping apical portions of the bolsters.

As shown in the figure, the leaves are attached along 

the upper third or more of the length of the bolster. 

Where the underlying bolsters are broken away, the 

leaves are seen to continue from the upper borders 

of the bolster with a slight dilation in width near the

" Bureau, £douard, op. cit. (Bassin houiller de la basse Loire), pi. 77, figs. 1-3, 

1913.

» Lesquereux, Leo, Report on the fossil plants of Illinois: Illinois Geol. Survey, 

Paleontology, vol. 2, p. 453, pi. 44, fig. 6,1866; Description of the coal flora of the Carboniferous formation in Pennsylvania and throughout the United States: Pennsylvania 2d Geol. Survey Kept. P, vol. 2, p. 382, pi. 64, fig. 5,1880.
FOSSIL FLORA OF THE WEDINGTON SANDSTONE 29

base, after which they taper gradually and evenly to the 

rather slender, acute apices. The leaf is ventrally 

round-sulcate over the midrib in the lower portion, 

and the lateral grooves, presumably holding the stomata 

and connecting with parichnoian developments, are 

rather narrow and faintly defined. The ligular pit is 

represented by a short needlelike protruding cast, 

seen on one or two of the bolster impressions. In a 

few places vague oval or rounded patterns, suggestive 

of the illustrations of leaf scars published in some of the 

earlier literature, are faintly indicated, but nothing 

which I can regard with confidence as outlining the 

vertical width of the foliar attachment or the parichnoian features is present.

Among other American species of Lepidodendron, 

this fragment appears to represent a form more closely 

related to Lepidodendron lanceolatum Lesquereux than 

to any other representative of the genus. Among the 

Old World types it is strikingly comparable to that 

described by Ettingshausen 76 as Lepidodendron hair 

dingeri.

The fragment from the Wedington sandstone is very 

similar both in the form of its bolsters and in the persistent broad, sharp-tapering upward-growing leaves 

to the specimen from the upper Culm figured by Bureau " as Lepidodendron lycopodioides from the lower 

Loire. It deserves comparison also with the leafy 

branches figured by the same author as Lepidodendron 

veltheimianum.78

Though represented by but a single fragment, the 

characters exhibited in the bolster and leaf of this stem 

appear to define a species hitherto undescribed. It is 

named in honor of the late Prof. A. H. Purdue, who 

for many years was engaged in the study of the geology 

of the region embracing the Wedington sandstone in 

northwestern Arkansas and who was author of the 

Winslow folio.

Locality: About 2 miles southwest of Prairie Grove, Ark.; 

collected by H. D. Miser and C. B. Read, 1931 (U. S. Geological 

Survey lot 8266).

Type: U. S. Nat. Mus. 39525.

Lepidodendron cf. L. veltheimianum Sternberg 79

Plate 5, figure 4

A slightly oval discoid impression of the attachment 

scar and border zone marking the position of a sessile 

lepidophytic cone is shown in figure 4, plate 5. The 

details of the scar are not well revealed by the sandy 

matrix.

The fragment is closely comparable to some of the 

cone scars left on the trunks of Lepidodendron of types 

referred by various authors to Lepidodendron veltheimianum, and in default of information showing to which

'6 Ettingshausen, C. von, Die Steinkohlenflora von Eadnitz in BShmen: K.-k. 

geol. Beichsanstalt Abh., Band 2, Abt. 3, p. 55, pis. 22,23,1854.

" Bureau, Edouard, op. cit., pi. 31, fig. 1; pi. 32; pi. 34, fig. 1.

«Idem, pi. 30 bis, fig. Ib, 1913.

" Stemberg, Kaspar, op. cit. (Flora der Vorwelt), Tentamen, p. xii, pi. 52, fig. 3, 

1825.

if any of the forms from the Wedington sandstone this 

is specifically referable,'I tentatively list it under the 

collective name. Comparisons may be made with the 

strobiliferous stems from the Waldenburg beds illustrated under L. veltheimianum by Stur.80 Similar cone 

scars have been described under Bothrodendron and 

Sigillaria, but without portions of the surrounding 

cortex bearing leaf scars characteristic of their respective genera the generic as well as the specific reference 

is questionable. Superficially the impression in hand 

is suggestive of the cone scars occurring on the rather 

large trunks described by Lesquereux from the Carbondale formation of Illinois under the name 

Ulodendron.

Locality: Bob Kidd Hollow, south of United States Highway 

62, 3.2 miles southwest of Prairie Grove, Ark.; collected by 

H. D. Miser, L. G. Henbest, and David White, 1930 (U. S. Geological Survey lot 8140).

Types: Figured specimen, U. S. Nat. Mus. 39526.

Lepidodendron wedingtonense White, n. sp.

Plate 7, figures 1-4, 6, 7, 9, 10; plate 9, figure 6

Trunks attaining moderately large size, branching 

rather frequently, often unequally, at a moderately 

wide angle; leaf cushions so arranged that those in the 

alternate rows are alined nearly transversely to the 

axis, fusiform in plan, slightly wider above the middle, 

very strongly and very obliquely protuberant, generally low-rounded dorsally, rarely slightly round-carinate along the medial line, irregularly and rather 

closely corrugated transversely both in the lower 

fields and above the leaf scar, and becoming separated 

at an early age by narrow marginal zones or borders 

which in the older parts of the trunk are clearly twisted 

at a low angle, each cushion being bounded by a separate strand; cushions appearing narrowly ovate with 

generally complete concealment of the leaf scar in the 

compressed specimen, by reason of the foreshortening of 

the upper part of the bolster; leaf scar borne at the 

summit of the protruding cushion and usually facing 

slightly upward, though sometimes inclined downward 

at a low angle, relatively broad, nearly straight across 

the base, laterally acute, and passing with very slight 

outward curvature of the margin to the high upper 

angle, which is rather narrowly rounded; vertical axis 

about two-thirds the transverse; nerve and parichnoian traces distinct and generally placed considerably below the medial line of the leaf trace, the nerve 

trace generally larger and slightly higher than the parichnoian traces, the distance between which is generally 

less than one-third of the width of the leaf scar; 

nerve sheaths ascending very obliquely in the cushions, 

appressed and acute in the Knorria stage; parichnoian 

appendages hardly visible in the impressions, invariably faint, rather narrowly elongated and convergent 

downward.

80 Stur, Dionysius, Die Culm-Flora: K.-k. geol. Beichsanstalt Abb., Band 8, Heft 

2, p. 278, pi. 22, figs, la, Ib, 2, 3a, 3b, 1877.
30 SHORTER CONTRIBUTIONS TO GENERAL GEOLOGY, 1936

The aspect of the fragments of this species is shown 

in figure 6, plate 7, in which 'the bolsters are slightly 

larger than the average, and figure 1, plate 7, in which 

they are smaller. Figure 1 illustrates the marked 

protrusion of the cushions in an obliquely ascending 

direction. Both of the figured specimens, which are 

impressions made by the bolsters as buried in the sand, 

show the corrugation of the cushions and the readiness 

with which the leaf scars may be totally concealed in 

compressed specimens. Only where the mold is slightly 

broken away is any portion of the leaf scar itself 

visible. A branch much smaller than the main axis or 

lower branched division is seen to emerge in the example shown in figure 1. The presence of elongated leaf 

cushions in the lower portion of the branch that is 

visible indicates probably a twig rather than the attachment of a cone. Both specimens show the characteristic diminution of the transverse corrugation as the 

leaf scar is approached from below. In fact, the 

cushion is in some specimens so nearly smooth below 

the leaf scar that in fragments completely compressed 

the upper part of the field might erroneously be taken 

for a part of the leaf scar which, owing to the rounded 

upper outline of the impression, might present a rather 

close similarity to the scars of Lepidodendron wortheni 

Lesquereux or some of the phases referred to Lepidodendron volkmannianum Sternberg.

In figure 4, plate 7, is seen the sandstone cast of the 

inner cortex of the specimen illustrated in figure 1. 

This shows the Knorria aspect, in which the neural 

tracts with surrounding transpiration tissue are seen to 

ascend very obliquely through the mesocortex. The 

end view of this cast of the partly compressed stem 

indicates approximately the very small size of the 

woody cylinder of the stem.

Leaf cushions of relatively large size are shown in 

figure 9, plate 7, and illustrate the ropy marginal zones 

bordering the bolsters as they become slightly distant 

in the older portions of the trunk. These marginal 

bands anastomose, but .the strands can generally be 

traced from cushion to cushion. Some of the bordered 

cushions of the old bark are somewhat elongated.

The form of leaf scar characteristic of Lepidodendron 

wedingtonense is shown uncovered in figure 9, plate 7. 

This specimen illustrates the relatively larger size of 

the nerve trace as compared with the lateral cicatricules. The traces appear to be relatively close to the 

lower border of the leaf scar on account of the slight 

deformation of the bolster under compression. The 

very broadly pyramidal profile of the upper border of 

the leaf scar as here shown is characteristic of the 

species.

The aspect of the smaller branches of the tree when 

they are partly compressed is illustrated in figures 2 

and 7, plate 7. As shown in figure 7, the transverse 

corrugation of the bolsters is evident, even in the relatively small branches. The phase in which the tissue 

underlying the outer cortex overlies the leaf scar and 

in Bergeria forms the outline of the leaf-cushion tract 

is illustrated by the specimen seen in figure 6, plate 9.

In the few specimens in which the cushions are but 

slightly compressed the leaf scars face nearly at right 

angles to the axis and protrude abruptly, some of them 

nearly 5 millimeters, from the general level of the leaf 

cushion. In fact, the protrusion of some of the leaf 

cushions is greater than their width.

Certain specimens have been observed which are 

interesting on account of the obscurity of the transverse 

corrugations in the lower portion of the cushions. 

The fields, which are but faintly carinate, appear to 

have been stretched slightly longitudinally.

This species, apparently the most common lepidophyte in the Wedington sandstone, is rather clearly a 

descendant of the Lepidodendron volkmannianum Sternberg stock, which is generally present in the upper and 

middle Chester wherever fossil plants have been found 

in beds of that age in the Midcontinent and Appalachian troughs. Many of the flattened impressions 

are strongly similar to the Old World species, though 

they are generally narrower, tapering more slenderly at 

the base. In the compressed stems the lower part of 

the bolster is rarely indented sufficiently to bring even 

a portion of the leaf scar into view. Besides the 

relative narrowness of the bolster and the much greater 

altitude and more pyramidal form of the leaf scar, the 

ropy marginal zones in the well-developed portions of 

the bark help readily to distinguish the species from 

Lepidodendron volkmannianum Sternberg. The faintly 

round-carinate form seen occasionally in the rounded 

leaf cushion also is distinctive.

On the other hand, though the angle of the leaf spiral 

is lower, it appears rather evident that the Wedington 

plant is closely related—perhaps lineally—to the 

Pennsylvanian species from the Midcontinent region 

described as Lepidodendron wortheni Lesquereux 81 and 

Lepidodendron brittsii Lesquereux.82 Both these forms 

appear to have shorter leaf scars that are of lower 

altitude and more rounded. The ropy marginal 

borders seen even in relatively young branches have 

not, I believe, been observed in either of the two 

Pennsylvanian species just mentioned. It is probable 

that neither of these species has so strongly protruding 

leaf cushions as those of Lepidodendron wedingtonense.

Another form of Lepidodendron with transversely 

corrugated bolsters is that from Macon erroneously 

illustrated by Vaffier 83 under the name L. acuminatum.

8i Lesquereux, Leo, Report on the fossil plants of Illinois: Illinois Qeol. Survey, 

Paleontology, vol. 2, pi. 49, figs. 4, 5, 1866; Description of the coal flora of the Carboniferous formation in Pennsylvania and throughout the United States: Pennsylvania 2d Qeol. Survey Kept. P, vol. 2, pi. 64, figs. 8, 9,1880.

8! Lesquereux, Leo, op. cit. (Coal flora), vol. 2, pi. 63, figs, l, 2,1880. White, David, 

Fossil flora of the Lower Coal Measures of Missouri: U. S. Qeol. Survey Mon. 37, 

p. 188, pi. 52, figs. 1, 2; pi. 53, fig. 1; pi. 64, figs. 1, 2,1899.

88 Vaflier, A., Etude gSologique et paleontologique du Carbonifere inferieur du 

Maeonnais: Lyon Univ. Annales, nouv. s6r., 1, Sci. m6d., fasc. 7, p. 133, pi. 9,1901.
FOSSIL FLORA OF THE WEDINGTON SANDSTONE 31

The characters of the leaf scars of Vaffier's specimens 

are not distinctly shown.

Lepidodendron henbesti is distinguished from Lepidodendron wedingtonense by its generally more distinctly 

diamond-shaped leaf cushions, by its closer crowding 

of the leaf cushions, apparently without intervening 

border zones even in the older stems,, by the small 

traces placed very low in the leaf scar, by the more 

numerous though generally not well-developed keels 

on the relatively flat cushions, and by the very slightly 

and irregularly zigzag branches, which divide much 

more frequently, at generally wider angles. In Lepidodendron henbesti the branches become very slender, 

hardly more than 3 millimeters in diameter, and 

branches 5 millimeters in diameter may give off subdivisions not more than 2.5 centimeters distant from 

one another. In this species, too, the leaf scar is 

relatively large, and the very young cushions, which 

may be nearly rhombic, are'not transversely corrugated.

Locality: About 2 miles southwest of Prairie Grove, Ark.; 

collected by H. D. Miser, L. G. Henbest, and David White, 

1930 (U. S. Geological Survey lot 8145).

Types: U. S. Nat. Mus. 39527-39535.

Lepidodendron sp. 1

Plate 8, figure 23

A single fragment in the collection offers characters 

such as apparently prohibit its reference to any of the 

forms described in the preceding pages. It is characterized by cushions that are not only slender but 

protrude so far and so obliquely as to give the frag*- 

ment the aspect of a Halonia. The details are shown 

clearly in the squeeze of the sandstone impression or 

mold photographed in plate 8, figure 23. The details 

of the leaf scar are indistinct, the leaves being still 

attached to the bolsters. The leaves, as indicated 

by the impression, are oblique and stand at an angle 

of less than 45° to the axis; they are relatively narrow 

and probably 8 or 10 centimeters in length, tapering 

gradually from the base to the slightly obtuse point. 

It may be assumed that the scars left by the detached 

leaves on the older stems will be relatively narrow in 

proportion to their height.

The plant in hand is easily distinguished from Lepidodendron purduei by the rigid, linear, elongated leaves. 

Apparently the cushions are relatively much narrower 

than in that species.

Locality: Cane Hill, Ark.; collected by H. D. Miser, L. G. 

Henbest, and David White, 1930 (U. S. Geological Survey lot 

8144).

Type: Figured specimen, U. S. Nat. Mus. 39536. 

Lepidodendron sp. 2 

Plate 7, figure 8

Represented only by the carbonized residue of a 

portion of a small branch; bolsters distant from one

another nearly one-third of their width, broadly 

diamond-shaped, acute at the base, slightly raised 

above the intervening cortex, a with somewhat protruded leaf scar above the middle or, in the compressed 

and foreshortened cushions, near the upper end, in 

which case the leaf trace and lower fields form a 

broadly ovate pattern, angular or obliquely truncated 

at the base; bolsters narrowly carinate a short distance 

below the leaf scar but some of them flatly arched as 

they approach the proximal angle; leaf scar relatively 

small, roughly rhomboidal in outline, right-angled or 

slightly obtuse-angled at the base, acute laterally, 

with drooping lateral crests, the upper borders slightly 

arched to form a rounded upper angle, the vertical 

diameter being about half the lateral; nerve trace near 

the center of the scar, punctiform; lateral cicatricules 

punctiform, nearly on the level of the nerve trace 

and distant from one another nearly half the longer 

diameter of the scar; lateral appendages faintly developed; ligular pit small, close to the upper angle of 

the leaf scar.

The single fragment of a small stem in which the 

cortical residue is preserved, as shown in figure 8, 

plate 7, is remarkable for the notable distance between 

the bolsters in contrast to the size of the stem. It is 

interesting as illustrating within the limits of a small 

fragment the foreshortening of the bolsters in its lower 

portion, those higher on the axis being broadly diamondshaped, with the exposure of the fields above the leaf 

scar. The form of the foreshortened bolsters, the relative size, and, to an extent, the shape of the leaf scar 

are comparable to those of the bolsters and leaf scars 

seen in some fragments referred by authors to Lepidodendron volkmannianum. There is, however, no 

trace of transverse corrugation in this specimen, even 

where the lower fields form a nearly flat area and the 

keels, some of which are seen below the leaf scars, are 

very nearly flat.

The small size and vertical shortness of the leaf 

scars preclude all reference of this fragment to Lepidodendron henbesti, and, on the other hand, there is no 

trace of the fusiform pattern or the transverse corrugation of Lepidodendron wedingtonense. Although no 

specimens showing the mature phases of the species 

represented by this fragment are at hand, and the 

fragment itself is none too well preserved, it is hoped 

that the illustration may aid in the recognition in some 

later collection of specimens that will more fully 

characterize the species and permit its satisfactory 

description or its identification with one already 

established.

Locality: Bob Kidd Hollow, south of United States Highway 

62, 3.2 miles southwest of Prairie Grove, Ark.; collected by H. D. 

Miser, L. G. Henbest, and David White, 1930 (U. S. Geological 

Survey lot 8140).

Type: Figured specimen, U. S. Nat. Mus. 39537.
32 SHOETEE CONTRIBUTIONS TO GENERAL GEOLOGY, 1936

Genus STIGMARIA Brongniart, 1822 84

Two species of Stigmaria have been found in the 

Wedington sandstone. In both, the root scars are 

relatively distant, though not so conspicuously remote 

as in the forms of Stigmaria in the lower zones of the 

Mississippian. In both the Wedington forms the 

umbilical scars are slightly smaller than in the typical 

Pennsylvanian species.

Stigmaria wedingtonensis is at once seen, by its 

coarse reticulation and the narrow zone of radiate 

areolation about the root scars, to be referable to the 

stellata group of Stigmaria, which is in general characteristic of the upper Mississippian. The other species, 

which for convenience is here called S. arkansana, is 

relatively smooth except where maceration and collapse have caused some irregular longitudinal wrinkling 

of the cuticle.

On the basis of the structure, which plainly was 

adapted to serve the purposes of transpiration as well 

as for maintaining the trunk in upright position, the 

application of the term "roots" to the upper subterranean divisions radiating from the base of the trunk, 

forking repeatedly and bearing the so-called "appendages" or true roots, has been questioned by some 

paleobotanists.

On account of its resemblance to the "roots" of 

Lepidodendron volkmannianum, which belong to the 

stellata group, and on account of the obviously close 

relation of Lepidodendron occidentale to Lepidodendron 

volkmannianum, it is believed that Stigmaria wedingtonensis is probably referable to L. occidentale, though 

it belonged possibly to Lepidodendron wedingtonense,vn.i}i 

which also it is associated. On the other hand, Stigmaria arkansana was perhaps attached to the tree here 

described as Lepidodendron henbesti.

Stigmaria arkansana White, n. sp.

Plate 5, figure 6; plate 9, figure 8

Surface relatively smooth with little indentation of 

the rootlet scars; surface of the parent "root" slightly 

rugose; umbilical scars relatively small, rather distant, 

with very narrow border rings.

The outer impression of the root of the species is 

shown in the small fragment illustrated in plate 9, 

figure 8, and a larger fragment, representing the subepidermal cast and embracing in its area the counterpart of the original of plate 9, figure 8, is shown in 

plate 5, figure 6.

The umbilical scars are slightly smaller in proportion 

to the size of the divisions of the "root" than in most 

of the later forms characteristic of the Pennsylvanian. 

The species is possibly to be associated with Lepidodendron henbesti, which is present at the same locality.

Locality: Bob Kidd Hollow, south of United States Highway 

62, 3.2 miles southwest of Prairie Grove, Ark.; collected by H. D.

84 Brongniart, Adolphe, Mus. bistoire nat. Paris M6m., tome 8, p. 228,1822.

Miser, L. G. Henbest, and David White, 1930 (U. S. Geological 

Survey lot 8140).

Types: U. S. Nat. Mus. 39538, 39539.

Stigmaria wedingtonensis White, n. sp.

Plate 5, figure 7; plate 9, figure 3

Root surface very coarsely pustulate-shagreened in 

short, broad areas which are close, irregular in arrangement, though in places roughly alined, and which vary 

but little in diameter with reference to distance from 

the root scar. Root scars relatively small and distant 

from one another, the umbilical cicatrix bordered by a 

narrow, rather sharply defined zone of small, radially 

slightly elongated tubercles.

This form of Stigmaria, which clearly is of Mississippian lineage, being related to the stellata group, is 

represented by but few fragments in the collection. 

The rather coarse meshing is shown on the mold, 

figure 7, plate 5, more distinctly than on the impression 

illustrated in figure 3, plate 9. The root scars, as 

shown in figure 7, plate 5, are apparently nearly in 

the plane of the intervening surface. The zone of 

small, radially arranged and pustulate-appearing areas 

is narrower than in most species of the stettata group. 

A notable feature, shown in figure 7, plate 5, is the 

smaller size and closer spacing of the root traces 

toward what is apparently the lower end of the parent 

"root", which, it may be inferred, is tapering in the 

same direction.

This species, which is believed to have been attached 

to Lepidodendron occidentale, is distinguished from the 

Pennsylvanian species of Stigmaria and from the one 

here described as Stigmaria arkansana by the coarsely 

pustulate-areolate surface of the parent root and by 

the narrow rings of radiate tubercles about the umbilical cicatrices. The species differs also from 

Pennsylvanian forms of Stigmaria by the slightly 

smaller and more distant umbilical scars, though this 

characteristic is not so marked as in the stellate forms 

from the earlier stages of the Mississippian.

Locality: About 2 miles southwest of Prairie Grove, Ark.; 

collected by H. D. Miser, L. G. Henbest, and David White, 

1930 (U. S. Geological Survey lot 8145).

Types: U. S. Nat. Mus. 39540, 39541.

Genus BOTHRODENDRON Lindley and Hutton, 1933 «« 

Bothrodendron sp.

Plate 7, figure 5

Leaf scars slightly raised on obliquely ascending, 

narrow, more or less faintly developed cushions, in 

relatively oblique alinement; leaf cushions oval, round 

at the base, deeply notched in V-shaped pattern at 

the top, apparently with distally radiating lines about 

the ligular pit; leaf scar situated in the upper part of 

the cushion, small; lateral cicatricules long, very

ss Lindley, John, and Hutton, William, The fossil flora of Great Britain, vol. 2 

pis. 80, 81 (description); pi. 117, p. 97,1833.
FOSSIL FLORA OF THE WEDINGTON SANDSTONES 33

narrow, rather distant, arching slightly outward, converging slightly at the lower ends, which are not far 

above the base of the leaf scar; cuticle apparently 

rugose.

Two fragments in the collections are rather clearly 

referable to the genus Bothrodendron. A cortical mold 

(pi. 7, fig. 5) shows very obliquely ascending vascular 

tracts terminating in none too well defined leaf scars. 

Though the details of the scar are by no means so 

well preserved as is desirable, the lateral cicatricules 

are fairly distinct, and there appears to be no doubt 

as to the presence of a ligular pit in the deep, acutely 

V-shaped notch at the upper end.

Another fragment, representing only a part of the 

width of an old stem, in which the cuticle had become 

irregularly torn longitudinally, probably in the natural 

process of growth, represents a welted or irregularly 

seamed impression broadly encrusted with carbonaceous residue. This phase of stretched cortex is of the 

type sometimes referred by Lesquereux to the genus 

Ulodendron. Here and there a few faint traces of leaf 

scars agree with the cortical impression shown in 

figure 5, plate 7.

Locality: Bob Kidd Hollow, south of United States Highway 62, 3.2 miles southwest of Prairie Grove, Ark.; collected 

by H. D. Miser, L. G. Henbest, and David White, 1930 (U. S. 

Geological Survey lot 8140).

Type: Figured specimen, U. S. Nat. Mus. 39542.

Genus LEPIDOPHYLLUM Brongniart, 1828 86 

Lepidophyllum sagittatum White, n. sp.

Plate 6, figure 3; plate 9, figure 2

Bract very narrowly triangular, acuminate, 4 millimeters wide at base, 3.5 centimeters long, tapering 

upward, with nearly straight or faintly concave margins, from the widest point, which is slightly above the 

base, and dorsally slightly round-convex, with distinct 

round midrib tapering upward and bordered by shallow 

and rather broad grooves; also marked dorsally by 

faint depressions slightly within the border; sporangiophore and sporangium uncorrelated.

The specimen illustrated in figure 3, plate 6, which 

is enlarged twice in order to show some detail, belongs 

to the Mississippian group of forms of Lepidophyllum, 

in which the bract, of moderate size, is narrowed more 

strongly and tapers gradually and more acutely than 

in the Pennsylvanian forms. In general size the bract 

in hand is comparable to the smaller representatives 

of the Lepidophyllum lanceolatum group of the Pennsylvanian. It is distinguished, however, by the narrowly triangular outline in which the margins pass 

nearly straight, with uniform convergence, from a 

point just above the base to the slender acute apex.

Locality: Bob Kidd Hollow, south of United States Highway 

62, 3.2 miles southwest of Prairie Grove, Ark.; collected by

is Brongniart, Adolphe, Prodrome d'une histoire des vfigetaux fossiles, p. 87,1828.

H. D. Miser, L. G. Henbest, and David White, 1930 (U. S. 

Geological Survey lots 8075 and 8140). 

Types: U. S. Nat. Mus. 39543, 39544.

Genus LEPIDOSTROBUS Brongniart, 1828 86 

Lepidostrobus occidentalis White, n. sp.

Plate 5, figures 1, 3; plate 8, figure 20

Cones linear, narrow, dense, rigid, round at the apex; 

bracts very delicate, about 11 millimeters long, 1 millimeter wide, linear-lanceolate, narrowed toward a 

relatively elongated distally protruding base or heel; 

sporangiophores in oblique spirals, apparently nine, 

nearly at right angles to the slender axis, very narrow 

just above the point of attachment, broadening gently 

in very narrowly obcuneate form, with relatively 

straight borders, to the base of the bract; sporangia 

narrow, elongated, slightly cordate at the distal end 

when compressed; spores not identified.

The species here described is represented by a few 

fragments only, which apparently fall within the comprehensive group generally rather loosely described under 

the term Lepidostrobus variabilis Lindley and Hutton.

The specimens have been badly water-worn, the bracts 

being nearly all abraded and generally even frayed. 

A fragment of stripped axis about 15 centimeters in 

length is incomplete. It indicates a linear, much 

elongated, rather rigid type of cone. As shown twice 

the natural size in figure 20, plate 8, which illustrates 

the detail of the impression of the axis, the ventral 

angle at the base of the sporangiophore is marked by 

a protruding narrow wedge or spine, which may be 

interpreted as ligular. The bases are relatively 

prominent. As seen in figure 3, plate 5, the sporangiophores stand nearly at right angles to the axis in all 

the fragments observed. Notwithstanding the advanced erosion, faint indications of the bracts, including the rather prolonged heels, are visible. At several 

points collapsed sporangial sacs appear to be present. 

These are narrow, smooth, and matte and, in the 

flattened state, have a rounded collar that does not 

appear to be closely adherent to the base of the 

sporangiophore. Unfortunately additional material 

illustrating the bracts, sporangia, and spores is lacking. 

The dark discoid object in the lower part of the cone 

seen in figure 3, plate 5, is a detached scar of Stigmaria 

lodged in the midst of the Lepidostrobus, as is shown also 

in the photograph of the counterpart, figure 1, plate 5.

Localities: Bob Kidd Hollow, south of United States Highway 

62, 3.2 miles southwest of Prairie Grove, Ark.; collected by 

H. D. Miser, L. G. Henbest, and David White, 1930 (U. S. Geological Survey lot 8140). About 2 miles southwest of Prairie 

Grove, Ark.; collected by H. D. Miser, L. G. Henbest, and 

David White, 1930 (U. S. Geological Survey lot 8145). Sixtenths of a mile south of junction of State Highway 99 and 

United States Highway 62, 4 miles west of Lincoln, Ark.; 

collected by H. D. Miser and C. B. Read, 1931 (U. S. Geological 

Survey lot 8268).

Types: U. S. Nat. Mus. 39545-39547.
34 SHORTER CONTRIBUTIONS TO GENEEAL GEOLOGY, 1936

Genus 1EPIDOCYSTIS Lesquereux, 1880 87 

Lepidocystis chesterensis White, n. sp.

Plate 6, figure 2

Sporangia small, rather narrowly obovate triangular, 

about 4.5 millimeters long and 3 millimeters wide, 

slightly rigid, with thin wall faintly rounded along the 

dorsal axis, which is longitudinal, shallowly and narrowly sulcate up nearly to the distal end, which is 

marked by a transverse oval depression just within 

the margin.

The aspect of the interesting and widespread form 

of sporangium here described is suggestive of a detached bolster related to Lepidodendron or Bothrodendron. The carinate dorsal axis rises to its highest 

point just beneath the transverse oval depression. 

This feature is illustrated in the impression of the 

specimen in figure 2, plate 6. In spite of the fact 

that the sporangial impression appears to be thin, it is 

nevertheless relatively rigid. Only occasionally is 

this fossil, which is common in the upper Mississippian 

of the Appalachian trough, deformed or folded. It is 

invariably isolated. The dimplelike depression at the 

upper end of the narrow dorsal crease may represent 

the ligular pit. The crease itself probably corresponds 

to the axis of the sporangiophore, and the transverse 

depression, present in all specimens and invariably 

characteristic of the type, may conform to the head of 

the sporangiophore or the heel of the bract. I have, 

however, never found Lepidocystis chesterensis in 

contact with the axis or sporangiophore; yet there can 

be little doubt as to its function as a spore holder. 

No megaspores are, however, in contact with the specimens in hand.

The American species just described is obviously of 

the same nature as the fossil from the Carboniferous 

limestone of Rothwaltersdorf described by Feistmantel 88 as Cardiocarpum rostratum.

Locality: Bob Kidd Hollow, south of United States Highway 

62, 3.2 miles southwest of Prairie Grove, Ark.; collected by 

H. D. Miser, L. G. Henbest, and David White, 1930 (U. S. 

Geological Survey lot 8075).

Type: U. S. Nat. Mus. 39548.

Genus ABCHAEOCAIAMITES Stur, 1875 »»

Calamarian remains, as might be expected from the 

arenaceous environment, are relatively common in 

the Wedington sandstone. Four types of stem fragments are found, all having rather clearly marked 

though not very thick woody zones, all essentially 

smooth or but faintly lineate or striate on the outer 

surface, and all marked by pith casts more or less

87 Lesquereux, Leo, op. cit. (Goal flora), p. 64,1880.

•» Feistmantel, Ottokar, Das Kohlenkalkvorkommen bei Rothwaltersdorf in der 

Grafschaft Glatz und dessen organische Einschliisse: Deutsche geol. Gesell. Zeitschr., 

Band 25, p. 640, pi. 17, fig. 38,1873.

89 Stur, Dionysius, Die Culm-Flora: K.-k. geol. Reichsanstalt Abb., Band 8, 

Heft 1, p. 9, 1875.

distinctly of the Bornia type, in which the nodes are 

relatively indistinct and foreshortened in some specimens to a mere transverse crease, whereas most of the 

pith ribs when exposed are seen to be continuous from 

internode to internode except as, in the enlarging 

stem, costae corresponding to the introduction of new 

vascular wedges are introduced in the internodes of 

increasing diameter.

Costae are seldom even faintly distinguishable in the 

impression of the exterior of the stem.

The larger stems from the Wedington seem all to 

fall within the range of variations to be found in the 

illustrations given by different authors under the name 

Bornia radiata (Brongniart) Schimper or Archaeocalamites scrobiculatus (Schlotheim) Seward. None of 

them agree, however, with the original illustration of 

Calamites scrobiculatus published by Schlotheim.90 

In the Old World type the pith ribs are much fewer and 

flatter, and the nodes are scarcely creased transversely, 

the cicatricules being punctiform, longitudinally elongated, and situated between the ribs. Schlotheim's 

type represents an earlier form and correspondingly 

lower stage.

In the type illustration of Bornia radiata, as published by Brongniart 91 under the name Calamites, the 

pith cast is sharply and deeply constricted at the nodes, 

and though the ribs are numerous and similar in aspect 

to those of Archaeocalamites wedingtonensis, the admission of the Wedington species under the same name 

is prohibited by its lack of the widely flaring, stellate, 

leafy nodal sheath illustrated and described very 

distinctly by the French author. It may be added that 

Brongniart's plant cannot, without violence to modern 

refinement in classification, be included under the same 

specific name with Schlotheim's Calamites scrobiculatus, 

which is further illustrated by Zeiller 93 in typical 

material.

In his great work on the Culm flora Stur 93 has described and figured a somewhat comprehensive series 

of stems representing several species, as I view them, 

under the name Archaeocalamites radiatus, the generic 

name being established for the group. Also he figures 

a large number of leafy stems with elongated dichotomously dissected Sphenophyttum-]itke leaves, including 

those described by Ettingshausen 94 as Schizaea transitionis. None of the stems from the Wedington sandstone are very close to those figured by Stur, though a 

leaf, possibly related to one of the stems and here

80 Schlotheim, E. F., Die Petrefactenkunde auf ihren jetztigen Standpunkt, p. 

402, pi. 20, fig. 4, 1820.

w Brongniart, Adolphe, Histoire des vSgfitaux fossiles, p. 122, pi. 26, fig. 4, Paris, 

1828.

•> Zeiller, Rene, VdgStaux fossiles du terrain houiller: Explication Carte gfiol. 

France, tome 4, pt. 2, p. 17,1879; atlas, pi. 169, fig. 2,1878.

* Stur, Dionysius, op. cit., Heft 1, p. 2, pi. 1, figs. 3-8; pis. 2, 3, 4; pi. 5, figs. 1, 2, 

1875; Heft 2, p. 74, pi. 2, figs. 1-6; pi. 3, figs. 1, 2; pi. 4, figs. 1, Ib; pi. 5, fig. 1,1877.

91 Ettingshausen, O. von, Die fossile Flora des ma~hriscb.-schlesiscb.en Dachschiefers: E". Akad. Wiss. Wien, Math.-naturwiss. KL, Denksehr., Band 25, pi. 17, fig. 

6, 1865.
FOSSIL FLORA OF THE WEDINGTON SANDSTONE 35

described as Archaeocalamites? sp., closely approaches 

Ettingshausen's Schizaea.

Associated with the Archaeocalamites stems are 

strobili bearing bifurcated sporangiferous bracts of 

sphenophylloid aspect, here described as a new genus, 

Cfdamidostachys. They have much the general superficial aspect of those first described as Pothocites Paterson and later assigned as fertile strobili to Archaeocalamites and are almost certainly related to them, 

notwithstanding some apparently important differences. The structure of these strobili is somewhat 

complicated, and on account of the partial maceration 

of the material and the gritty matrix, information as 

to the distal portions of bracts and the structure is still 

inadequate.

Though all the calamarian stems in the Wedington 

are referable to Archaeocalamites, the aspect of Archaeocalamites wedingtonensis and in particular of Archaeocalamites umbralis is suggestive of the developing 

typical calamitean stem, in which not only are the 

nodes distinct and the costae mainly alternate but the 

internodes are not so crowded one against the other and 

the interlacing of the lax vascular strands is usually 

easily observable. Evidence of leaf scars at the upper 

ends of the costae of the pith casts is distinctly observed 

only in Archaeocalamites umbralis. In Archaeocalamites 

wedingtonensis and Archaeocalamites fayettevillensis the 

presence of leaves is indicated only by neutral pits of 

pin-point size connecting with the trace of the vascular 

system between the costae. In the rather remarkable 

little stem described as Archaeocalamites gracilentus. 

however, some, at least, of the nodes are distinguished 

externally by protrusions of the outer woody zone that 

have the aspect of rapidly tapering blunt spines. These 

protrusions, which may be merely the bases of abraded 

appendages, are borne, few in number, in verticils at the 

conspicuously dilated nodes. In view of the thick wood 

of the plant it is possible that these are the remains of 

branches provided with thick wood at their very bases.

One only of the stem fragments, tentatively referred 

to Archaeocalamites wedingtonensis, is provided with 

distinct verticils of small oval nodal scars. None of 

the calamarian stems of the Wedington exhibit so 

frequent alternation of costae at the node as is seen in 

Calamites ramifer Stur and other forms, including most 

of those referred to Archaeocalamites in the basal 

Pennsylvanian of the Appalachian trough.

Archaeocalamites fayettevillensis White, n. sp.

Plate 9, figure 10

Stems of rather small size, smooth or finely striate 

externally, with moderately distant internodes, which 

are faintly indicated externallp and are marked with 

a very narrow, sharp, shallow depression in the pith 

cast, across which the very narrow, rather closely placed 

costae pass with relatively rare alternation.

This species, represented by but few specimens in 

the collection, one of which is shown in figure 10, plate 

9, is rather easily differentiated from the associated 

forms by the narrow and slightly crowded ribs. As 

seen in the illustration, the external impression of the 

stem is nearly smooth, with extremely faint indication 

of costation and, as in associated species, with faint 

expression of articulation. Articulation is, however, 

plainly seen in the pith cast, which is slightly constricted at the immediate node, which is very narrow. 

The costae are nearly as narrow as those in the larger 

fragments of the very slender species described below 

under the name A. gracilentus'. No evidence of branching or appendages is seen. Details as to leaf scars and 

appendages await the discoveiy of additional material.

The specimen illustrated invites comparison with 

one of the fragments figured by Stur 95 as Calamites 

ramifer, though that specimen is much more finely 

costate than the other pith casts described under the 

same name, besides which the nodes in the Arkansas 

specimen are much less distinctly calamarian in aspect.

Localities: Bob Kidd Hollow, south of United States Highway 

62, 3.2 miles southwest of Prairie Grove, Ark.; collected by 

H. D. Miser, L. G. Henbest, and' David White, 1930 (U. S. 

Geological Survey lot 8075). About 2 miles southwest of Prairie 

Grove, Ark.; collected by H. D. Miser, L. G. Henbest, and David 

White, 1930 (U. S. Geological Survey lot 8145).

Type: U. S. Nat. Mus. 39549.

Archaeocalamites gracilentus White, n. sp.

Plate 9, figures 1, 5, 9

Stems very slender, tapering downward extremely 

gently to a slender pointed base; rather distantly 

articulate, finely lineate on the outer surface of a thin 

woody outer cylinder, and dilated rather abruptly at 

the nodes, some of which are marked by verticils of 

several small rounded tubercular protrusions corresponding to short, extremely open, rapidly tapering 

bases of appendages or branches; pith cast slightlv 

constricted at the nodes, which become increasingly 

closer in the tapering base and distinctly costate, with 

very narrow, slender, straight, rather prominently 

rounded costae, some of which appear slightly crowded.

This very graceful and interesting species is rather 

rare at the localities at which collections of plants were 

made from the Wedington sandstone. It is, however, 

easily recognized by the very slender stems, the narrow 

costae of the pith cast, the closely and distinctly lineate 

impression of the outer cortex, and the dilation of the 

cortex at the nodes, many of which are marked, as 

shown in figures 1, 5, and 9, plate 9, by short, blunt, 

rapidly tapering processes that apparently represent 

the bases of appendages or bracts, and which are marked 

internally by small oval impressions suggesting tubercles in small numbers, forming verticils at some of the

M Stur, Dionysius, Die Culm-Flora: K.-k. geol. Reichsanstalt Abb., Heft 2, p). 

21, flg. 4, 1877.
36 SHORTER CONTRIBUTIONS TO GENERAL GEOLOGY, 1936

nodes. Such verticils are imperfectly shown in the 

upper part of figure 9. In this fragment, which is one 

of the largest seen among the specimens of this species, 

the rather typical sharply indented archaeocalamitian 

node is seen in the lower part.

The fragment illustrated in figure 5, plate 9, is so 

smooth on the outer surface that it might readily be 

passed as the slender petiole of a fern or some other 

plant. Careful examination reveals indications of the 

pith costae. The dilated node near the upper end of 

the fragment, from which the pith cast has been 

removed, shows a semispinous appendage or appendicular base on each side and pits marking the neural 

tract of two others in the slightly compressed mold. 

In the specimen photographed in figure 1, plate 9, 

is seen the rounded edge of a slightly flattened stem. 

Here the thickness of the carbonized outer cylinder is 

shown and the dilation of the cylinder at the node in 

the upper part of the fragment. In this example, 

as in that shown in figure 9, plate 9, the pith cast 

itself is constricted at the node, but the costae are 

continuous, the stem being nearly uniform in size. 

From the uniformity in size of the stem and the apparent absence of introduced costae at the node, as well 

as from the fact that the woody residue is in this form 

developed as in others, it is concluded that the stem 

is mature and of full size. The costae of the pith cast 

are faintly seen to be very finely lineate.

One unfigured specimen is unusually interesting in 

that it shows the long, tapering, slender bases of several 

stems which converge and which possibly were attached at a single node of a rhizome or parent stem. 

As with other specimens, the impression of the stem, 

in which the cuticle was in contact with the matrix, 

reveals no trace of costae. However, both the costation and the constricted nodes of the pith are well 

shown at the left. It should be noted that this impression extends, with very slight diminution in the 

extreme lower portion, very nearly to the lower edge 

of the rock fragment, and the dilations at the nodes 

are apparent nearly as far as the cast can be traced 

in place, though they are not so prominent at the lower 

end of the mold.

Archaeocalamites gracilentus differs so markedly from 

all other calamarian material in the collection that 

its differentiation is exceedingly evident. No other 

species has such marked nodal dilation as this, and 

none bears spinelike processes arranged in verticils at 

the nodes.

The similarity between the stems here described as 

Archaeocalamites gracilentus and those from the Moravian-Silesian roof slates described by Ettingshausen 96 

as Catamites tenuissimus Goeppert is remarkably close. 

Information is lacking, however, as to the pith casts 

of the plant from the roofing slates, but, on the other 

hand, no leaves such as those figured by Ettingshausen

«« Ettingshausen, C. von, op. cit., p. 16, text fig. 2, pi. 1, figs. 1, 2,1865.

are observable on the American material, which 

superficially resembles even more closely the stems 

described by Paterson 97 and Kidston 98 as belonging 

to Pothocites grantonii.

The slender stems here described invite comparison 

with the axes of the cones from the Wedington, to 

which the name Chlamidostachys is given, for both on 

account of the characters of those axes and the analogies 

between Chlamidostachys and Pothocites, which is borne 

by a stem very similar to Archaeocalamites gracilentus, 

it seems not improbable that A. gracilentus may have 

supported the strobili mentioned above. No trace of 

bifurcation, such as is reported in the stem of Pothocites, 

is observed in the Wedington specimens, but in both 

forms the stem is very slender, being comparable in 

size, with rather long internodes, which are striate 

externally, with costate piths, and which may be 

provided at the nodes with protuberant processes or 

short blunt spines, marking the origin of probable 

branches. Between the two types of cones also there 

are notable similarities, which are pointed out in the 

description of Chlamidostachys (p. 39). Therefore, the 

discovery of additional material may show union 

between Archaeocalamites gracilentus and Chlamidostachys chesterianus. Pothocites is regarded as the fruit 

of Archaeocalamites scrobiculatus (Schlotheim) Seward, 

its leaves being indentified by Kidston with Sphenophyllum tenerrimum Ettingshausen. However, the 

variation in the types of fruit and in the leaves referred 

to Archaeocalamites scrobiculatus or its synonym Bornia 

radiata only emphasizes the view already stated that 

this name covers an aggregate of species that should 

be susceptible of differentiation.

Locality: About 2 miles southwest of Prairie Grove, Ark.; 

collected by H. D. Miser, L. G. Henbest, and David- White, 

1930 (U. S. Geological Survey lot 8145). Fragments apparently 

referable to the species are included also in U. S. Geological 

Survey lot 8075, collected at Bob Kidd Hollow, 3.2 miles southwest of Prairie Grove, Ark.

Types: U. S. Nat. Mus. 39550-39552.

Archaeocalamites umbralis White, n. sp.

Plate 9, figure 4

Stems comparatively small, slender, tapering rather 

gently downward in the lower part, with relatively short 

segments two to three times as long as thick, dilated 

slightly at the nodes, with distinct outer vascular zone 

of moderate thickness, and nearly smooth externally 

between the nodes; articulations distinct in the pith 

cast, marked with thickening and slight dilation of the 

vascular cylinder; internodal pith cast slightly enlarged 

just above and just below the articulation and marked 

by about 20 comparatively broad, prominently rounded 

ribs that are rather obtusely rounded distally, though

87 Paterson, Robert, Description of Pothocites grantonii, a new fossil vegetable from 

the coal formation: Bot. Soc. Edinburgh Trans., vol. 1, p. 45, pi. 3,1841.

« Kidston, Robert, On the affinities of the genus Pothocites Paterson, with the 

description of a specimen from Glencartholm, Eskdale: Annals and Mag. Nat. 

History, 5th ser., vol. 11, p. 304,1883.
FOSSIL FLORA OF THE WEDINGTON SANDSTONE 37

generally alined across the node and marked a little 

below the node by rather large but generally faint leaf 

scars; intercostal or canilicular furrows narrow and 

rather deep; surface of ribs of pith cast very finely and 

apparently irregularly striate; outer cortex very finely 

lineate.

The type of stem illustrated in figure 4, plate 9, 

appears to be not rare in the upper part of the Mississippian of eastern America, though in the collection from 

the Wedington sandstone it is represented by only a 

few fragments that are clearly referable to this species. 

The nodes are slightly dilated and marked by thickening of the vascular cylinder, in which the articulations 

are relatively distinct. The thickness of the outer 

cylinder is especially notable toward the base of this 

specimen.

The species is further characterized by the short 

nodes and the relatively broad costae of the pith cast, 

which are rather distinctly rounded at the upper ends. 

The ribs are dorsally high-rounded, with relatively 

narrow intervening sulci. The articulation in this stem 

is more clearly shown in the pith casts than in any of the 

other species from the Wedington sandstone, though 

the internodes of the pith are closely set and the ribs 

generally in continuous alinement. The aspect of the 

pith cast is more distinctly calamarian than that of the 

associated species, yet the node itself lacks the prevalent 

intertwining of the neural strands seen in the later types 

found in the Pennsylvanian. The compactness of the 

articulations and the general continuity of the costae of 

the pith, combined with the rather thick vascular cylinder, associate the plant with the later forms of Archaeocalamites. The impression of the outer cortex, a portion 

of which is shown in figure 4, plate 9, shows little trace 

of costation and but faint evidence of articulation.

Archaeocalamites umbralis resembles in general form 

and size the lower portion of a stem figured by Stur " as 

Calamites haueri. In Stur's species, however, from the 

Waldenburg series, the ribs are partly alternate, with 

distinct leaf traces and well-marked nodes of the calamarian type.

Localities: About 2 miles southwest of Prairie Grove, Ark.; 

collected by H. D. Miser, L. G. Henbest, and David White, 1930 

(U. S. Geological Survey lot 8145). A portion of a pith cast 

nearly twice the size of that figured but presenting the same costal 

characters and tentatively referred to the species, although 

exhibiting undulation of the ribs, probably the result of mechanical deformation, is present in U. S. Geological Survey lot 8140 

from Bob Kidd Hollow, 3.2 miles southwest of Prairie Grove, 

Ark.

Type: U. S. Nat. Mus. 29553.

Archaeocalamites wedingtonensis White, n. sp.

Plate 9, figures 7, 12, 13

Stems of moderate size, tapering rather gently 

toward the base and divided into internodes varying

»• Stur, Dionysius, Die Culm-Flora: K.-k. geol. Reichsanstalt Abb., Band 8, 

Heft 2, p. 90, pi. 5, figs. 3a, 3b, 1877.

from three times to twice the diameter of the stem, 

the nodes being hardly visible in the external impression and marked by faint narrow transverse depressions on the pith cast; outer surface generally smooth, 

rather distinctly and distantly lineate, with minutely 

striate interspaces; pith cast distinctly costate where 

free from remains of external tissue, with straight 

and regular, generally low-rounded costae, dorsally 

rather distinctly lineate, nearly all in continuous 

alinement in the larger stems, and separated by rather 

broad sulci in which the casts of the canals are generally 

distinct and rather large; leaf scars apparently small 

and obscure.

This species is one of the commonest in the Wedington sandstone. The general aspect of the cast is 

shown in figure 12, plate 9. The distinctness of 

specific characters varies with the state of preservation and, in particular, according to the maceration 

of the outer cylinder with consequent masking of 

the characters. In some of the specimens, such as 

that shown in figure 7, plate 9, both costation and 

nodes are completely concealed beneath the residue 

of the outer tissue and cuticles. This feature is shown 

also in portions of the reverse of the specimen, seen in 

figure 12, plate 9, where the partly macerated woody 

cylinder shows little but the impression of the finely 

lineate cuticle, which is finely striate between the 

rather distinct lines. All expression of costation is 

lost, and the nodes are hardly discernible with certainty in the specimen shown in figure 13, plate 9, 

though some specimens clearly reveal the costation 

on a portion of the somewhat macerated pith. The 

external impressions of such examples may easily be 

mistaken for the impressions of petiolar fragments of 

ferns.

Evidence of the presence of leaves or branches is 

generally obscure. Minute pustular scars are visible 

at the upper ends of the ribs in some of the fragments, 

and small scars, hardly larger than pin points, mark 

corresponding connections with the pith cast. Several 

of the specimens show very faint and rather small 

depressions, apparently corresponding to branches or 

the attachment of fructifications at the joints. That 

illustrated in figure 7, plate 9, though somewhat 

macerated and deformed, shows the depressions more 

clearly than any other in the collection. In this 

example we see a row of very small, closely placed, 

slightly discoid impressions elongated somewhat in 

the longitudinal direction and marked by punctate 

neural scars somewhat above the middle. It is 

possible that the fertile strobili described on page 38 

as Chlamidostachys chesterianus were borne by the 

type of stems here distinguished as Archaeocalamites 

wedingtonensis, though it is probable that they were 

connected with Archaeocalamites gracilentus, for reasons 

stated under the heading of that species.
38 SHORTER CONTRIBUTIONS TO GENERAJy GEOLOGY, 1936

Archaeocalamites wedingtonensis is distinguished by 

the relatively large size of the stem as compared with 

the associated species; by the typical Bornia type of 

nodal demarcation, the node being, however, very 

slightly constricted; and by the low-rounded costae 

of the pith cast, which are distinctly lineate, whereas 

the intercostal sulci are moderately broad and the 

neural casts usually distinct and relatively large. 

Furthermore, the residues of the outer zone, including 

the woody cylinder and the external envelopes, usually 

completely mask the costation of the pith cast, frequently concealing also the presence of the nodes 

themselves. The stems are very much larger and the 

ribs narrower, less closely placed, and less distinctly 

marked at the nodes than in Archaeocalamites umbralis, 

in which the nodes are somewhat dilated. On the 

other hand, the costae of the pith cast are much 

broader and more distantly spaced than in Archaeocalamites fay ettevillensis.

The ribs of the pith casts of the species from the 

Wedington are proportionately considerably narrower 

than in the Old World specimens figured as Asterocalamites scrobiculatus (Schlotheim) Seward or its supposed 

synonyms. An exceptionally near approach to the 

stem in hand is found in one of the specimens figured 

by Schimper l as Catamites radiatus.

Localities: Bob Kidd Hollow, south of United States Highway 62, 3.2 miles southwest of Prairie Grove, Ark.; collected 

by H. D. Miser, L. G. Henbest, and David White, 1930 (U. S. 

Geological Survey lots 8075 and 8140), and by H. D. Miser 

and C. B. Read, 1931 (U. S. Geological Survey lot 8264). Cane 

Hill, Ark.; collected by H. D. Miser, L. G. Henbest, and David 

White, 1930 (U. S. Geological Survey lot 8144). About 2 

miles southwest of Prairie Grove, Ark.; collected by H. D. 

Miser, L. G. Henbest, and David White, 1930 (U. S. Geological 

Survey lot 8145).

Types: U. S. Nat. Mus. 39554-39556.

Archaeocalamites? sp.

Plate 9, figure 11

On account of its very close similarity to some of the 

foliage referred by various authors to Archaeocalamites 

scrobiculatus, the leaf fragment shown in figure 11, 

plate 9, is tentatively referred to the genus Archaeocalamites, with the recognition of the consequent 

implication that one species in the Wedington flora 

may be identical or very close to a European form 

gathered by authors into the group species Archaeocalamites scrobiculatus (Schlotheim) Seward. That 

not all the forms under this collective name are specifically identical is proved by the differences in their 

leaf characters and in then: fruits. The figured 

specimen is the sole representative Archaeocalamites 

leaf in the collections from the Wedington. There is 

no stem of Sphenophyllum or fern similar in leaf. The 

bracts and the sporangia of the associated cones, 

Chlamidostachys, are distinctly sphenophylloid.

i Schimper, W. P., Les vfigetaux fossiles, in Koechlin-Schlumberger, J., and 

Schimper, W. P., Le terrain de transition des Vosges, pi. 1 (see fig. a only), 1862.

Except that the Arkansas leaf is very much smaller, 

it agrees closely with the plant described by Ettingshausen 2 as Schizaea transitionis. It is three times 

dichotomously divided, but the greater part of the 

left lobe of the first subdivision is broken away. The 

divisions are relatively rigid, nearly equal in width, 

slightly flexuose, bifurcating at a narrow angle, and 

slightly divaricate. The terminal divisions taper and 

are acute, with slightly thickened margins. The 

lamina is not very thick and is nearly flat. The 

primary nerve bifurcates at a very narrow angle not 

far below the points of division of the leaf. The 

nerves passing into the tertiary divisions originate by 

bifurcation in the upper part of the secondary division 

and pass nearly parallel through the tertiary.

Both as to size and form the fragment illustrated 

may be compared especially with the illustrations 

given by Stur to show the foliate stems from the 

Moravian-Silesian roofing slates.3

Locality: Bob Kidd Hollow, south of United States Highway 

62, 3.2 miles southwest of Prairie Grove, Ark.; collected by 

H. D. Miser, L. G. Henbest, and David White, 1930 (U. S. 

Geological Survey lot 8075).

Type: Figured specimen, U. S. Nat. Mus. 39557.

Genus CHLAMIDOSTACHYS White, n. gen. 

Chlamidostachys chesterianus White, n. sp.

Plate 8, figures 11, 17, 18, 19, 21

Strobili large, reaching a length of 10 centimeters or 

more and varying in width from 2.5 to 3 centimeters 

or more; hardly rigid, cylindrical, rounded at the apex, 

with fluted axis 2.5 to 3 millimeters wide, articulated 

transversely at distances of 2.5 to 2 millimeters, thecostae being continuous in alinement on each side of 

the articulation; nodes provided with verticils of approximately nine sporangiophores; sporangiophores 

open nearly at right angles to the axis, some slightly" 

reflexed, some inclined slightly distad, thick, narrowest 

very near the base, broadening upward, slightly concave ventrally, low round-arched dorsad, forking or 

giving off narrow linear lateral branches, those in the 

lower portion very oblique, those at a distance of 

about 7 millimeters from the axis very open and dividing in four or five subdivisions, apparently arranged in. 

peltate form and splitting parallel to the main axis of 

the cone or at nearly a right angle to the basal portion 

of the sporangiophore; form of peltate subdivisions 

apparently variable, obcuneate-ovate to round-ovate 

and ovate-elliptical, some of them 5 millimeters or 

more in length, and invariably appressed so as to define 

the outer surface of the strobilus; lower portions of the 

sporangiophore provided with a broad, thin wing, 

which curves upward and slightly inward to form a 

cylindrical or semicylindrical chamber in which oval

» Ettingshausen, C. von, Die fossile Flora des mahrisch-schlesischen Dachschiefers: 

K. Akad. Wiss. Wien, Math.-naturwiss. KL, Denkschr., Band 25, p. 27, pi. 7, fig. 5,. 

1865.

'Stur, Dionysius, Die Culm-Flora: K.-k. geol. Eeichsanstalt Abh., Band 8, Heffe 

2, pi. 3, p. 8, 1877.
FOSSIL FLORA OF THE WEDINGTON SANDSTONE 39

or oblong-lanceolate sporangia, in groups of four or 

five, are borne in asteriform arrangement about short 

pedicels springing obliquely from point to point along 

the ventral side of the basal portion of the sporangiophore; sporangia, whose groups are sparsely scattered 

on the surface of the sporangiophore, dehiscent by a 

ventral slot or elongated opening, reaching from the 

base halfway or quite to the apex and varying in width, 

those on the upper divisions of the sporangiophore, 

including the lower portions of the broad peltate ultimate subdivisions, being generally smaller than those 

nearer the axis of the cone, though much elongated 

groups simulating soil appear to be borne on the 

ventral surface of some of the appressed outer lobes, 

so as to form low rounded prominences on the outer 

surface of the cone.

The fertile strobili here described present certain 

features strongly resembling the strobili of Pothocites 

as originally described by Paterson 4 and as later 

critically revised by Kidston.5 In fact, noticing 

rounded protuberances and obscure resemblances to 

scattered "stellate bodies" on the surface of the strobilus, I was at first disposed to place the Arkansas 

specimens in the Scotch genus. Further examination, 

however, showed cloarly that the American material 

belonged to a distinct undescribed genus. In both 

genera we have slender cylindrical cones with closely 

appressed bracts, arching in low rounded prominences, 

arranged in longitudinal series. As originally described 

some of these rounded protuberances, each corresponding to a bract, are capped by structures resembling 

quadripartite sporangia, in which the sporangia, lanceolate or linear-oblong in shape, are spread out flat 

about the central point of attachment and are open 

longitudinally for their entire length. Kidston, who 

reviewed the species, all from the Calciferous Sandstone 

series and mostly from Glencartholm, near Eskdale, 

near Edinburgh, described the sporangia as generally 

four in number, borne on the concave under surface of 

the quadrangularly peltate dilation of a sporangiophore 

that originates in the axis of the cone. The cone itself 

is borne by a slender rigid smooth stem, which is 

described as branching. Pothocites grantonii Paterson,4 

Pothocites patersoni Etheridge,6 and Pothocites calamitoides Kidston,7 together with an unnamed species of 

Pothocites described by Etheridge,6 were finally referred 

by Kidston to the single species Pothocites grantonii, 

which he ascribed to the single species Bornia radiata, 

more generally known as Asterocalamites scrobiculatus.

4 Paterson, Robert, Description of Pothocites grantonii, a new fossil vegetable from 

the coal formation: Bot. Soc. Edinburgh Trans., vol. 1, p. 45, pi. 3,1841.

5 Kidston, Robert, On the affinities of the genus Pothocites Paterson: Annals and 

Mag. Nat. History, 5th ser., vol. 10, pp. 404-405, 1882; On the affinities of the genus 

Pothocites Paterson, with the description of a specimen from Glencartholm, Eskdale: 

Idem, vol. 11, pp. 297-314, pis. 9-12, 1883; Bot. Soc. Edinburgh Trans. and Proc., 

vol. 16, pp. 28-38, pis. 1-4, 1885.

6 Etheridge, Robert, Note on the further discovery of a species of Pothocites 

(Paterson) in the lower Carboniferous rocks near West Calder: Bot. Soc. Edinburgh 

Trans., vol. 12, p. 151, 1874.

7 Kidston, Robert, On the affinities of the genus Pothocites Paterson: Annals and 

Mag. Nat. History, 5th ser., vol. 10, p. 404, 1882.

Much remains to be learned regarding the structure 

of the cone from the Wedington sandstone. The features exhibited, however, show that it differs generically from Pothocites, though it was, I suspect, similarly 

borne on a slender pipestemlike stalk, which in this 

paper is described as Archaeocalamites gracilentus. In 

Pothocites the axis of the cone is described as cylindrical, 

the sporangiophores being in 10 (?) vertical rows. 

Further, the sporangiophores are interrupted at regular 

intervals of about 2 centimeters (?), where a verticil of 

normal sterile filiform dichotomous bracts marks the 

abrupt constriction of the cone, the axis of which may 

be exposed for a very short interval. However, the 

most important generic distinction lies in the broad, 

sb'ghtly fleshy, and thinly alate sporangiophore of 

Chlamidostachys, which widens cuneately upward with 

branching nervation in sphenophylloid fashion and 

which becomes laciniately cut in sphenophylloid lobation at * the dilated and generally closely appressed 

upper portion. The sporangia, oval or round-oval, are 

borne in groups of four or five on short pedicils springing from the nerves on the ventral surface of the lower 

fertile portion of the bract. I have seen no evidence 

of any peltate enlargement at the top of the pedicil. 

In fact, in the flattened specimens the sporangia, which 

apparently open longitudinally, present an aspect suggestive of Asterotheca. In a few specimens the abruptly 

appressed upper portion of the bract presents a lowrounded surface comparable to the protuberances on 

Pothocites, and in a few specimens, owing possibly to 

the displacement of the tips of the lobes of the bract, 

the impression presents a roughly stellate configuration 

in which three or four lobes suggest the external patterns drawn by Paterson and Kidston from the Scotch 

specimens. It is not too much to say that these resemble canoe-shaped sporangia lying flat on the surface 

of the cone and opening longitudinally along their 

ventral axes, as in Pothocites. This aspect may be 

accidental and mechanical. The explanation awaits 

the collection and detailed examination of additional 

material. On the other hand, it does not appear to the 

writer that a satisfactory explanation has yet been given 

of the stellate structures on the outer surface of Pothocites, which are arranged in four or five vertical rows 

and also in distantly spaced verticils, while the groups 

of sporangia, several times as numerous, are crowded. 

Certainly they do not appear to accord with the quadrisporangiate group borne on short sporangiophores 

springing from the axis of the cone, as described by 

Kidston.

So far as the general structure of Chlamidostachys is 

revealed by the specimens in hand, it defines a type of 

fructification more nearly comparable to that of 

Sphenophyllum than to any of the equisetalean or 

calamarian genera. Certain features of the cone suggest Bowmannites or even Cheirostrobus. It will be 

noted that the axis of the cone of Chlamidostachys 

appears to be articulated, that the bracts springing
40 SHORTER CONTRIBUTIONS TO GENERAL GEOLOGY, 1936

from the nodes are verticillate, and that the internodes 

are distinctly fluted, as in the calamarian cone. In 

view of the sphenophylloid type of leaf, such as that 

described as Archaeocalamites sp. (pi. 9, fig. 11), associated with the branches of Asterocalamites, and in 

view of the structure, so far as at present known, of 

Chlamidostachys, the question arises whether there are 

not now classed under the term Bornia or its synonymns 

Archaeocalamites and Asterocalamites, plants which cannot properly be included among the Equisetales or 

Calamariales and which are more nearly related, though 

perhaps intermediate, to the Sphenophyllales. On the 

assumption that Chlamidostachys is really associated 

with the archaeocalamitean type of forked leaf and that 

the Wedington cone is borne on an archaeocalamitean 

stem, consideration should, according to my view, be 

given to the revision of the classification of the sphenophylloid group of Archaeocalamites and its possible 

systematic differentiation.

Asterophyltites spaniophyllus Feistmantel,8 from the 

Carboniferous limestone at Rothwaltersdorf, which was 

referred by Stur 9 as the fruit of Archaeocalamites 

radiatus, has a verticil of spiral leaves filling five verticils of fertile bracts but without constriction of the 

cone, as in the Scotch Pothocites.

Bureau argues that Archaeocalamites scrobiculatus is a 

comprehensive type which, like the genus Cordaites, 

produces a diversity of fruits representing species far 

more numerous than is indicated by the stems and 

foliage. To a fruit from the upper Culm of the basin 

of the lower Loire Bureau 10 gives the name Bornia 

pachystachys and regards it as associated with Bornia 

transitionis, under which he places Archaeocalamites 

scrobiculatus. However, in Bureau's Bornia pachystachys, as in Bornia grand'euryi Renault u and Bornia 

esnostensis Renault, 12 the cones are without bracts, the

8 Feistmantel, Ottokar, Das Kohlenkalkvorkommen bei Rothwaltersdorf in der 

Qrafschaft Qlatz und dessen organische Einschliisse: Deutsche geol. Qesell. Zeitschr., 

Band 25, p. 498, pi. 14, fig. 5, 1873.

» Stur, Dionysius, Die Culm-Flora: K.-k. geol. Reichsanstalt Abh., Band 8, Heft 2, 

p. 74, 1877.

10 Bureau, Edouard, Bassin houiller de la basse Loire, fasc. 2, Description des flores 

fossiles, p. 240; atlas, pi. 65, figs. 1, 2; pi. 66, figs. 1-5; pi. 67, figs. l-5a, 1914. (In the 

series "Etudes des gltes minSraux de la France.")

11 Bureau, Edouard, Les fructifications du genre Bornia: Soc. sci. nat. ouest France 

Bull., 3« ser., tome 3, p. 122, pi. 5, fig. 6, 1913.

12 Renault, B., Bassin houiller et permien d'Autun et d'Epinac, fasc. 4, pt. 2, 

Flore fossile, p. 82,1896; atlas, pi. 43, figs. 1-10,1893. (In the series "Etudes des gites 

minSraux de la France.")

sporangia being borne in groups of four to six on more 

or less distinctly peltate sporangiophores springing 

directly from the axis.

The diversity of fructification referred to the 

Archaeocalamites stock is further illustrated by Nathorst's Pothocitopsis, another type of cone, apparently 

without bracts, from the lower Carboniferous of 

Spitsbergen,13 regarded by its author as closely related 

to Pothocites.

Locality: Bbb Kidd Hollow, south of United States Highway 

62, 3.2 miles southwest of Prairie Grove, Ark.; collected by 

H. D. Miser, L. G. Henbest, and David White, 1930 (U. S. 

Geological Survey lot 8140).

Types: U. S. Nat. Mus. 39558-39562.

Genus SPHENOPHYLLUM Koenig, 1825 " 

Sphenophyllum? sp.

Plate 8, figure 16

A plant fragment photographically illustrated in 

figure 16, plate 5, though problematic and solitary, is 

of such unusual interest that attention should be drawn 

to it, if only for the purpose of encouraging the search 

for additional specimens. A single slender curved 

stalk or petiole broadens rapidly about 3 millimeters 

from the base into a lamina that is apparently cut 

nearly to the base in two lobes, one of which^is broken 

away but which were probably equal or nearly equal. 

The left lobe appears to present the characters of 

Sphenophyllum. It is cuneate, narrowing, with convex 

borders, rather rapidly at the base, the margins diverging but slightly in the upper part, and truncate and cut 

in four or five blunt sphenophylloid teeth at the apex. 

A single nerve forks at the base of the lobe and again 

at a very narrow angle somewhat higher, to furnish a 

nerve that passes upward into the marginal teeth. 

The lamina is thick and granular-rugose. It is of 

course possible that the fragment may belong to a 

dichotomous pinnule of a fern or pteridospermic leaf.

Locality: Bob Kidd Hollow, south of United States Highway 

62, 3.2 miles southwest of Prairie Grove, Ark.; collected by 

H. D. Miser and C. B. Read, 1931 (U. S. Geological Survey lot 

8264).

Type: Figured specimen, U. S. Nat. Mus. 39476.

is Nathorst, A. G., Nachtrage zur paMozoischen Flora Spitzbergens: Zur fossilen 

Flora der Polarlander, Teil 1, Lief. 4, p. 78, pi. 3, figs. 5 and 6,1914. (See Pothocitopsis 

bertillii.)

» Koenig, C., Icones fossilium sectiles, p. 42, 1825.
PLATES 4-9

41

U. S. GEOLOGICAL SURVEY PROFESSIONAL PAPER 186 PLATE 9

9 13

FOSSIL FLORA OF THE WEDINGTON SANDSTONE MEMBER OF THE FAYETTEVILLE SHALE.

1; 5; 9. Archoeocalamites gracilentus White, n. sp.

2. Lepidophyllum sagittatum White, n. sp.

3. Stigmaria wedingtonemis White, n. sp.

4. Archaeocalamites umbralis White, n. sp.

6. Lepidodendron wedingtonense White, n. sp.

7; 12; 13. Archaeocalamites wedingtonensis White, n. sp.

8. Stigmaria arkansana White, n. sp.

10. Archaeocalamites faiietteeillensis White, n. sp.

11. Archaeocalamites sp.
U. S. GEOLOGICAL SURVEY PROFESSIONAL PAPER 186 PLATE 8

21 

FOSSIL FLORA OF THE WEDINGTON SANDSTONE MEMBER OF THE FAYETTEVILLE SHALE.

23

1; 2; 3; 4; 5; 6; 7; 8, 22; 12; 13; 14. Rhynchogonium fayettevillense White, n. sp.

9,1O; 15. Carpoliihus inquirenda White, n. sp.

11; 17; 18; 19; 31. Chlamidostachys chesterianus White, n. gen. et sp.

16. Sphenophyllumf sp.

2O. Lepidostrobus occidentalis White, n. sp.

S3. Lepidodendron sp.
. S. GEOLOGICAL SURVEY PROFESSIONAL PAPER 186 PLATE 7

10

FOSSIL FLORA OF THE WEDINGTON SANDSTONE MEMBER OF THE FAYETTEVILLE SHALE. 

1; 2; 3; 4; 6; 7; 9; 1O. Lepidodendron wedingtonense White, n. sp. 5. Bothrodendron sp. 8. Lepidodendron sp.
C. S. GEOLOGICAL SURVEY PROFESSIONAL PAPER 186 PLATE 6

FOSSIL FLORA OF THE WEDINGTON SANDSTONE MEMBER OF THE FAYETTEVILLE SHALE.

1; 4; 5; 6, 9; 7, 8. Lepidodendron henbesti White, n. sp. 2. Lepidocystis'chesterensis White, n. sp 3. Lepidophyllum sagittatum White, n. sp.
U. S. GEOLOGICAL SURVEY PROFESSIONAL PAPER 186 PLATE 5

FOSSIL FLORA OF THE WEDINGTON SANDSTONE MEMBER OF THE FAYETTEVILLE SHALE.

1; 3. Lepidostrobus occidentalis White, n. sp.

2. Telangium(?) sp.

4. Lepidodendron cf. L. veltheimianum Sternberg.

5; 8. Lepidodendron occidental White, n. sp. 

6. Stigmaria arkansana White, n. sp.

7. Stwmaria wedingtonense White, n. sp. 

9. Lepidodendron purduei White, n. sp.
U. S. GEOLOGICAL SURVEY

31

FOSSIL FLORA OF THE WEDINGTON SANDSTONE MEMBER OF THE FAYETTEVILLE SHALE.

1. 6. Rhacopteris sp.

2. 3. Rhodea cf. R. subpetiolata (Potonie) Nemejc.

4, 5; 11, 18; 13, 14; 15; 17, 31; 2O; 22; 23, SO; 36, 39.

sippiana White, n. sp. 

7, 8. Sphenopteris cf. S. schimperiana Goeppert.

9. Sphenopteris cf. S. communis Lesquereux.

10. 16. Sphenopteris (.Palmatopteris) erectiloba White, n. sp.

12. Sphenopteris cf. 8. obtusiloba Brongniart.

19, 24; 25. Rhodea cf. R. moravica (Ettingshausen) Star.

26, 38; 27. Neuropteris sp.

39; 31, 33; 33, 34; 35; 37. Cardiopteris hirta White, n. sp.

38. Adiantites minima White, n. sp.

4O, 41. Cardiopteris sp.