SMITHSONIAN INSTITUTION

On the Crinoid Genus

SC YPHUCRINUS

And its Bulbous Root

CAMAROCRINUS

(With 9 Plates )

BY
FRANK SPRINGER

ASSOGIATE IN PALEONTOLOGY, U. S. NATIONAL MUSEUM

(Publication 2440)

CITY OF WASHINGTON
PUBLISHED BY THE SMITHSONIAN INSTITUTION

1QI7

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Presented by the

Smithsonian Institution
at the

Request of the Author

SMITHSONIAN INSTITUTION

On the Crinoid Genus

SCV HOC RINGS

And its Bulbous Root
CAMAROCRINUS

(With 9 Plates)

BY

FRANK SPRINGER
ASSOCIATE IN PALEONTOLOGY, U. S. NATIONAL MUSEUM

(Publication 2440)

CITY OF WASHINGTON
PUBLISHED BY THE SMITHSONIAN INSTITUTION

1Q17

The Lord Baltimore Dress

BALTIMORE, MD., U. 8. A.

FOREWORD

This paper, originally intended merely as an account of a remarkable dis-
covery in 1912, having a decisive bearing upon the distribution and morphology
of the genus Scyphocrinus, and its relation to the bulbous organism hitherto
called Camarocrinus, has by force of repeated further acquisitions of material
expanded into a memoir requiring for its illustration nine plates and numerous
text-figures. The drawings for the plates were executed by Mr. Kenneth M.
Chapman, now of Santa Fé, New Mexico, with his usual skill and fidelity. The
text-figures have been prepared with much care by my assistant, Mr. Herrick
E. Wilson, whose studies of the structural details have greatly facilitated the
present explanation of the internal characters of the Camarocrinus bulbs. For
the valuable aids thus contributed I wish to express to both these gentlemen
my acknowledgment and appreciation.

FRANK SPRINGER.
WASHINGTON, January 17, 1917.

CONTENTS

PAGE

Maer UC ELT | as veays a pee jchene sprees uerey ensure sumone ace lecwhe sere eew er ceuets eiepayederetotenal opel kelctetsvereweneyere I
TA SEO May OL GISCOVETYaieh epi siapatscciete isla yer sie iaasy see cet anereietet ciel chore er sterek-eueestak sete h Caro renee 3
Descriptionnabe ther SpecimenSun sa. esc ac ace mice mise reise reereren neve citensielsl korres 6
Gonclusionpasston CAsHarOcrinusmnnn wre een eee eee Ores 9
Construction and: probablevorioin of thembulbs) Sey ra lactase es se renctenersiev)eleleleiare 14
Modetofaunionibctweenplatestini sc pHOcrinusier ctu situate oielctlalsts Ve tereokekeieveken eres 19
(bhesAmenicanysSpeciesnOl SGV PHO GLI USN melee sievcteye elatocteled seotey ol betters evoked sn aehebelersaste ratte 21
DESEmiptomiOl they species! re qnem ilies diactytre: such a edaueen ulenaieliaeeyebetevalmnelos asa/aeskey seaiete eked ve fetes 30
Scyphocrinus elegans Zenker (Pls. 1; II; III, figs. 1-4; IV; V, figs. 1-5)....... 30
Hurther remarks: upon the fixed pinnulesk).i. 9. eyseio sis eee aie loiter eee 40
Scyphocrinus. spinifer; mew species (Pl TX, figs. ta-c) 2.0.08.) .2 ee eee ne 46
Scyphocrinus mutabilis, new species (Pls. VI, figs. 3-19; VIII, figs. 3, 4, 5)...... 47

Sey pnocrinus:srelatusn (Elall\i (el Vale esiiAgsD)) avec etre eietetstarct se teiceetel siete see 49

Scyphocrinus prattenti (McChesney) (Pls. VII, figs. 1a, b; VIII, figs. 1 2a, b)... 50
Scyphocrinus pyburnensis, new species (Pls. VII, figs. 2a, b, 3; VIII, figs. 6a, b, 7). 52
Seyphocrinus ulrichi, new species (Pl. IX, figs. 2a, b) .........0.....220 0000: 54
Scyphocrinus gibbosus, new species (Pl. IX, figs. 3a, b) ......... 0... sc eee eee 55
JOgukwenuoil Ohi WEWE! Sous donpbneongunaqoeauboomoboonupoGcHobonUcbucaocooueed 57

ON THE CRINOID GENUS SCYPHOCRINUS AND ITS
BULBOUS ROOT CAMAROCRINUS

By FRANK SPRINGER
ASSOCIATE IN PALEONTOLOGY, U. S. NATIONAL MUSEUM

(Abstract read before the Paleontological Society of America, December, 1912. Résumé by R. S. Bassler,
toc. U. S. National Museum, vol. 46 (Nov., 1913), pp. 57-59, plates 1 and 2)

INTRODUCTION

For more than half a century there have been known to paleontologists
certain bulb-like, supposedly crinoidal or cystoidal, bodies which were described
from American localities by Hall in 1869 as Camarocrinus. Similar structures
had been known long before that from rocks in Bohemia considered of Silurian
age, to which Barrande had given the name Lobolithus, without description.
For a full account, with ample illustrations, of their morphology and occurrence,
and of the pertinent literature, reference may be made to Professor Charles
Schuchert’s admirable paper of 1904, On Siluric and Devonic Cystidea and
Camarocrinus.

These organisms may be briefly described as large bulbous, chambered
bodies, with thick walls composed of irregular plates, and to one end of which
are attached roots and the terminal portion of a stem similar to those of
crinoids.

Hall’s interpretation of this structure was that the “probable theory in
regard to this fossil points to a functional similarity with a crinoidal root,
* * * Viewing it in this respect it may be regarded as a large chambered bulb,
with an attached column, on the distal extremity of which was a calyx having
characters unknown at the present time. In this aspect it must have been a
free floating organism, similar in its habits to the recent Meduse and
Comatule.” *

This view in substance has been generally held by subsequent authors.

Dr. Bather * in 1900 definitely associated Camarocrinus with the Camerate
genus Scyphocrinus, as a root, “ perhaps connected with a free-floating exis-
tence.” And Dr. Kirk* in 1911 considered it “ firmly established * * * that the

¢

*Smithsonian Miscellaneous Collections, vol. 47, pt. 2, pp. 253-272, 1904.
228th Report New York State Museum, p. 206, 1879.

*Lankester, Treatise on Zoology, pt. 3, p. 135, 1900.

“Proc. U. S. National Museum, vol. 41, pp. 54-56.

2 SMITHSONIAN INSTITUTION

bodies known as Camarocrinus or Lobolithus are the distal expansions of
Scyphocrinus.”

The following is a summary of the then known facts touching the occur-
rence and relations of Camarocrinus and Lobolithus, as marshaled by Schuchert
in the work above cited, with his correlations of the horizons at that time:

1. They occur in widely separated localities; viz., in Bohemia in étage E? to E? of
the Silurian, to be correlated with the American Rochester shales; in the Manlius division
of the Silurian of New York and West Virginia; in the Helderbergian of Tennessee
and Oklahoma.

2. In the Bohemian localities they occur in some beds associated with Scyphocrinus,
and in others where no Scyphocrinus has been found.

3. In America Scyphocrinus is unknown, and the Camarocrinus bulbs have never been
found associated with any other crinoid, except rarely the stemless Edriocrinus attached
as to any other foreign body.

4. They are frequently found in great numbers together in beds where there is no
sign of other crinoidal remains.

5. In no place throughout the formations in which these bodies occur are there
corresponding beds replete with crowns, stalks, or even accumulations of separated ossicles
of crinoids.

6. The great majority of the bulbs are found in the strata with the stalked end
downward.

Mr. Schuchert’s conclusion was as follows:

Camarocrinus thus appears to be the float of an unknown crinoid that was held
together after the death of the individual by the firmly interlocked double walls of the
exterior and the interior, while the crown and stalk dropped away. Under this hypothesis,
the float drifted with the sea currents, was finally filled with water, and, the attenuated
end being heavier, sank in that position?

This is substantially the same as Hall’s interpretation.

The supposition that these bodies were anchored in the mud with the
stalk end directed upward he thinks too much at variance with the facts stated
in paragraphs 4 and 6 above.

He adds finally:

This writer realizes that the last word has not been said in regard to Camarocrinus,
and the present work is offered with the hope that some paleontologist will attack the
problem from another point of view.

In 1906 Mr. F. R. Cowper Reed* noted the occurrence of Camarocrinus
at Yemeyé, Burma, in rocks designated as Ordovician, but of whose age he
said the evidence was “not quite conclusive,’ and described a new species,
C. asiaticus. In the accompanying remarks upon the genus the author observed:

‘

The nature of this curious fossil is still a matter of discussion, but the balance of
opinion is in favor of regarding it as a float of some crinoid or crinoids, as Hall originally
supposed.

*Smithsonian Miscellaneous Collections, vol. 47, pt. 2, p. 269, 1904.
*The Lower Palaeozoic Fossils of the Northern Shan States, Burma, Mem. Geol. Surv. India,
n. s., vol. 2, mem. 3, p. 88

CRINOID GENUS SCYPHOCRINUS 3

Later, in 1913, Mr. Reed’ described and figured from the same locality
another specimen of the same species with the base of the stem and its branch-
ing roots attached, but he still treated the stem-bearing side of the fossil as
the “lower surface ” and the opposite rounded side as the “ upper surface”;
although noting the opinions of Sardeson and others that these bodies are the
specialized roots of crinoids, a question which he says “can hardly be regarded
as finally settled.’ See also La Touche, 1913, who definitely proves the
association of Camarocrinus with Scyphocrinus in the rocks of Burma.

Upon the facts as known at the date of Schuchert’s paper I concurred in
his conclusion. But important information since obtained, culminating in a
very remarkable recent discovery, throws new light on the question—com-
pelling the abandonment of the above statements 3, 5, and 6, and a reconsidera-
tion of the conclusion based upon them. The newly discovered evidence shows
instead:

1. That the genus Scyphocrinus occurs abundantly in America.

2. That the Camarocrinus bulbs are directly connected at the distal end of the stem
with crinoids belonging to that genus.

3. That these bulbs when in their original position occur with the stalked end upward,
and not downward as before supposed.

c

HISTORY OF DISCOVERY

The facts in support of these statements are briefly as follows:

I have had for a long time, among collections made by Wachsmuth from
Helderbergian strata in Perry County, Tennessee, now designated as the
Linden formation, several fragments of a large crinoid belonging to the
Melocrinidz, of whose generic position we were uncertain. A few years ago,
thanks to the kindness of the late Professor Whitfield, I came into possession
of a cast of the type specimen of the form described by McChesney” as
Forbesiocrinus (Melocrinus in second edition*) pratteni, said to be from the
Carboniferous limestone of Alabama but the actual position and locality
unknown, the original of which was lost in the Chicago fire. On assembling
this and the above mentioned fragments it was apparent that they all belonged
to the genus Scyphocrinus, and I have no doubt that McChesney’s specimen
came from the same horizon somewhere near the Tennessee-Alabama line.
Later on, among other collections made in the Linden beds of Perry and
Hardin counties, Tennessee, was found an excellent large calyx, in all respects
like McChesney’s type, with two others probably of a different species. Some
other crinoids were found in the same exposures, and a number of Camaro-
crinus bulbs, but not im situ or in any definite association.

1Rec. Geol. Surv. India, vol. 43, pt. 4, Dp. 335-338.
?Mem. Geol. Surv. India, vol. 39, pt. 2, pp. 119-123.
Trans. Chicago Academy of Sciences, vol. 1, p. 29, 1860.

“Tbid., Republication, 1868, p. 22, pl. 5, fig. 4.
2

4 SMITHSONIAN INSTITUTION

During the season of 1910 Mr. Frederick Braun, while collecting for me
in western Tennessee, discovered at several localities of the same horizon in
Benton County numerous unmistakable fragments of Scyphocrinus associated
with those of Camarocrinus in the same deposits. They were in the much
disintegrated remains of what had evidently been a bed of considerable extent,
and the appearance of the specimens and their mode of preservation were so
similar as to indicate a common origin. All were fragmentary, and the strata
from which they were derived were not located in place. In Hardin County,
Dr. August F. Foerste had some years before collected from an equivalent bed
a number of unusually fine specimens of Camarocrinus; these were very firm,
globose, and heavy, much like those described by Schuchert from Oklahoma.
Their occurrence was noted in his paper on Silurian and Devonian Limestones
of Western Tennessee, but nothing was said about any other associated
remains.

Among later collections made by Dr. E. O. Ulrich in the Camarocrinus
bed of the Haragan limestone of Oklahoma were found two good calices of
Scyphocrinus, thus supplying the evidence of association in that region which
had before been wanting. In the meantime there had also been obtained among
collections made at the West Virginia locality part of the calyx of a small
species of Scyphocrinus, which established a similar association with the
Camarocrinus occurring in those beds. These last occurrences have been noted
by Dr. Kirk’ in his paper on Eleutherozoic Pelmatozoa.

In 1904 Dr. R. S. Bassler, as recorded by Schuchert, observed Camaro-
crinus associated with numerous large crinoid stems a few miles north of Cape
Girardeau, Missouri, along the bluffs of the Mississippi River, in a layer
belonging to strata of the Bailey limestone (considered to be about equivalent
to the New Scotland beds) of Helderbergian age; and in 1911 Dr. Ulrich found
a detached mass of limestone from the same layer composed almost entirely
of crinoid stems cemented together, among which was imbedded the well-
preserved calyx of a large Scyphocrinus. The condition of the specimen was
so promising of favorable results as to warrant a special investigation, in hope
of finding the fossiliferous bed at some place sufficiently exposed for careful
collecting.

Accordingly, during the season of 1912, Mr. Braun was sent to this
locality for the purpose of a thorough examination, and after protracted search
for several miles along the bluffs facing the Mississippi River, he succeeded
in locating the crinoidal layer at an accessible point.’ Here, with his usual

*Journal of Geology, vol. 11, p. 683, 1903.

* Proc. U. S. National Museum, vol. 41, p. 55, IOIT.

*Rep. U. S. National Museum, p. 80, 1913; Proc. U. S. National Museum (Bassler), vol. 46,
p. 58, 1913.

CRINOID GENUS SCYPHOCRINUS 5

skill and patience, he prosecuted quarrying operations for several weeks, which
resulted not only in the recovery of some of the most remarkable specimens
of fossil crinoids ever obtained, but in settling finally the facts upon which the
interpretation of Camarocrinus must depend. It was a work of no small
difficulty, as the physical obstacles were formidable. The layer could be readily
traced, but it was not everywhere fossiliferous, and when it was a place had
to be found with a soft seam underneath along which it could be easily separated
from the one next below. Even then it still remained to be seen whether good
specimens would be found exposed when the rock was lifted from its bed.
Several feet of overlying material had first to be removed, and it was then
found that the crinoids were limited to the lower 2 inches of a heavy bed of
impure argillaceous limestone, averaging 6 to 7 inches in thickness. This could
not be parted by splitting, and it was therefore necessary to remove the upper
half by the slow process of chipping with hammer and chisels, in order to
reduce the slabs to manageable weight. This done, the remaining part of the
layer was pried up in as large pieces as possible, parting readily from the
underlying rock along the line of an intervening seam of fine-grained clay,
which adhered closely to the lower surface of the slabs, where alone the crinoids
were found in good condition.

This fact is important to remember: that while the lower two inches of
the bed is chiefly composed of a dense mass of crinoid stems, firmly cemented
together with a scanty matrix passing gradually into the limestone above—the
calices and other parts scattered through them crushed, broken, and distorted
by pressure—it is only on the under side, where the adherent clay has acted
as a mould and protected them from the effects of the pressure, that the crowns
are found well preserved.

The material taken up was not all equally rich, some of it having to be
rejected because barren. The fossiliferous part of the layer proved to be
limited to a small area, and it is evident that the fossils found here are the
remnant of a thickly crowded colony, suddenly killed by some change in the
water or movement of the sea bottom, and imbedded in the soft mud without
much disturbance by currents. Four large slabs were selected of about 500
to 1,500 pounds weight each, together with some smaller pieces, the whole
weighing 4,500 pounds. Two of the slabs fit together, forming a single one
of nearly 4 by 7 feet, containing the most important specimens (PI. I).

The locality was several miles distant from any station or landing, and
it was necessary to transport lumber to make strong packing cases for the
slabs, bedding them in plaster to secure the specimens from injury in handling.
Then a chute 60 feet long was constructed to slide the packages down with
ropes and tackle over a sloping rock levee of about 35 feet (vertical) descent
to the water’s edge, where they were shipped on a passing river steamboat.

6 SMITHSONIAN INSTITUTION

All this was accomplished by Mr. Braun with perfect accuracy and without
the slightest mishap; and it is a pleasure to record my appreciation of the care
and skill with which, under many adverse conditions, he performed this diffi-
cult and laborious work.

Some of the specimens were partially exposed upon the slabs as first taken
out, but it was necessary after their arrival at the National Museum to clear
away the adherent clay with fine tools before their contents could be fully seen
or intelligently studied. Furthermore, the interbrachial spaces were filled with
a more or less hard calcareous matrix composed of innumerable arm and
pinnule joints forced down between the arms and firmly cemented by pressure
from above; this had to be removed by patient chipping to expose the interesting
structures in the region of the arm-bases.

DESCRIPTION OF THE SPECIMENS

The surface after removal of the clay seam was found to be in many
places completely covered with the crowns and stems of a very large Scypho-
crinus. The principal slab (Pl. 1) is 47 by 65 inches in size, and contains 24
crowns, 18 of them complete and several with the stem attached for part of
its length; some have the calyx fairly rotund, but most of them are considerably
flattened and often much distorted by contact with the bulbs described below.
All have the strong, many-branched arms more or less intact, often to a length
of 12 inches, densely fringed with exceedingly fine pinnules, which are so
delicate that they are not often exposed in good condition by cleaning. The
distal ends of arms are so slender and fragile that they are nowhere fully
preserved, but from measurement of the smallest brachials and calculation
of the taper of the terminal branches as far as seen, it is certain that the arms
were at least 18 or 20 inches long. The calices are remarkably regular in size,
measuring about 44 to 5 inches from base to the upper limit of fixed plates.
Besides these crowns several sets of arms are partly visible belonging to calices
which are entirely buried either under other individuals or in the limestone
matrix which becomes firm and hard a short distance inward. Some parts of
the slab are covered with a dense mass of stems lying parallel like stalks of
grain in a sheaf, and many of the crowns lie with their arms pointing in the
same direction, as if they had fallen over into the mud at the same time under
the common impulse of a gentle current. The deposition of the specimens,
however, was not wholly free from disturbance; some of them lie crosswise,
and most of the stems are more or less broken; in some closely contiguous parts
of the bed the crowns are much broken, the calices crushed and separated from
the arms. The fossils are mostly rather light colored, and with the darker
matrix for a background they present a very striking appearance.

CRINOID GENUS SCYPHOCRINUS 7

In no case can the stem be traced to the distal end; all of them at a short
distance from the crown either pass under other crowns, or become enveloped
in the general mass of remains. Therefore we do not know the full length of
the stem, but this must have been considerable, since incomplete portions are
seen for distances of 18 to 30 inches, and the quantity of stem remains is very
great in proportion to the number of crowns.

Intermingled with the crowns and stems are a number of Camarocrinus
bulbs; some of these are well exposed and appear of good size (PI. I, at
H and J), while in many cases only a part can be seen among the other objects
(Pl. I, at K). All of them are considerably flattened, and some are fractured
from the pressure of the overlying mass of remains which was consolidated
into the compact limestone deposit forming the main thickness of the heavy
layer. For this reason none have the complete rotundity and undistorted form
of the West Virginia, southern Tennessee, and Oklahoma specimens, of which
the stems and crowns have been detached and swept away by currents, and the
bulbs left buried in the mud. But the broken condition of many of the bulbs,
and of some of the calices in contact with them, is very similar to that of the
fragmentary remains found by Mr. Braun in Benton County, Tennessee, which
undoubtedly came from a colony deposited under like circumstances to this one.
Counting broken ones, there are about 15 of these bulbs more or less visible
upon the surface as now exposed. This slab, of which a photograph is herewith
given (Pl. I), is now installed for exhibition in the Hall of Invertebrate
Paleontology of the National Museum.’

In all there are about 50 of the bulbs to be seen in the material under
consideration. Most of them are well exposed on the lower surface of the
rock, and in general it may be remarked that in those areas where the bulbs
predominate in this condition crowns are scarce, and vice versa. Where they
have been lying side by side in the mud in close contact both are more or less
distorted or broken, as already explained; and it is evident that the bulbs in
their original condition were fragile structures, by no means so solid and rigid
as they appear when free; on the contrary, their walls were relatively light, thin,
and porous, easily crushed and broken, a large part of their volume consisting
of compartments containing soft parts or water.

In another piece from the same bed is a cluster of five bulbs within an
area of about one square foot; they are almost entirely free from stems or
other remains, and the matrix passes directly into the firm limestone, thus
indicating that they were near the edge of the colony; and when the forest of
crinoids went down before the destroying agency, whatever it was, the stalks
fell away from these roots, leaving them imbedded in the mud where they grew,

4Proc. U. S. National Museum (Bassler), vol. 46, p. 59, 1913.

8 SMITHSONIAN INSTITUTION

flattened, but otherwise intact. Four show the rounded end, and one the side.
And this brings us to the next important fact:

In not a single instance among the total of about 50 bulbs seen on all the
slabs is the stalk end directly exposed; in a few cases the bulb lies sidewise,
and indications of some of the root-branches may be seen at the edge; but in
no case is the stem directly traceable from a bulb zm situ, although rarely frag-
ments of broken bulbs are found with the root-branches attached. This accords
with Schuchert’s observations of slabs from West Virginia and Oklahoma;
but this fact in the light of the new knowledge we now possess leads to directly
the opposite conclusion from that which he deduced from it. For it must now
be recalled, as I have already emphasized, that these bulbs as we find them
are upon the under side of the layer, and therefore their rounded, non-stalked
ends, as they now appear after cleaning, were directed downward in their
actual position as originally imbedded in the mud. Hence they stood with
the stalked end uppermost, as they naturally would if growing in or resting
upon the soft sea bottom.

I have no doubt that this was also the case with the specimens mentioned
by Mr. Schuchert. From long experience in collecting in many formations,
I have observed it to be the general rule that whenever crinoids are found
adhering to a layer of hard limestone or chert, with the parts in relief bedded
in a seam of softer material, they are from the under side of the layer, and not
the upper; and their position as seen in the museum is exactly the reverse of
their original position in the layer, or on the sea bottom. This is perfectly
shown on all the slabs of Uintacrinus, as I have elsewhere described;* and I
have found the same to be the case with colonies adhering to cherty layers
in the Burlington and Keokuk beds, where the practice of collectors was always
to strip down to the layer so as to uncover it as much as possible, and then to
lift the slabs with pick or crowbar, expecting to find the crinoids on the under
surface. It was so at Beachler’s great locality on Indian Creek, Indiana, where
over 3,000 finely preserved crinoids were obtained, most of them from the
lower side of the layer.

The deposits of Pentacrinus at Lyme Regis, England, as described by
Buckland’ in 1837, were made in the same way, the perfectly preserved
Pentacrinites, found only on the lower surface of the slabs, having been
“buried in the clay that now invests them,” with a mass of stems above them
passing into a layer of lignite. There also, as here, “the greater number of
these stems are usually parallel to one another, as if drifted in the same direc-
tion by the current.”

* Uintacrinus, Mem. Mus. Comp. Zool. Harvard, vol. 25, no. I, p. 5, I9OI.
* Geology and Mineralogy (Bridgewater Treatise), p. 437.

CRINOID GENUS SCYPHOCRINUS 9

At the famous colony of Crawfordsville, where the soft layers are much
thicker and without any distinct capping of hard limestone, the crinoids were
more gradually deposited, and are found more generally diffused throughout
the beds. But in other cases as usually found the colonies were quickly
killed by a change in the content or condition of the water, and settled quietly
into the soft mud in a thick mass, followed by a calcareous or siliceous deposit
producing limestone or chert above them; thus the parts next to the mud were
largely preserved intact, while those above them were crushed, flattened, or
consolidated by the pressure and more or less cemented into rock, which would
thus form a firm backing for the specimens below it. If there were a strong
current, the stems and crowns of the crinoids would be swept away, while any
imbedded or firmly anchored roots would remain in the mud; and they might
or might not become attached to a firm layer above them according to the
character of the deposit immediately following. A limestone plate would not
be so likely to form, owing to the removal of the other calcareous parts of the
crinoids which would help to produce it.

The occurrence at Keyser, West Virginia, mentioned in Mr. Schuchert’s
paper (p. 260) where he saw ten Camarocrint upon a large slab detached from
nearly vertical strata by blasting, must be considered in the light of these facts.
I have not the least doubt that they were upon the under side of the layer as
originally situated, and that the unstalked end as presented by nearly all the
bulbs which he saw partly buried in the mud was the under part as they had
rested in the sea bottom. The small slab from Oklahoma, with five specimens
on the “upper” surface (ibid. p. 261, pl. 43), was no doubt in the same
condition; so that the bulbs, “not one of which had the stalk end turned
upward,” are actually seen from the under side, and not the upper. There is
no direct evidence of the original position of these slabs in the strata from
which they were derived, so that it cannot be positively asserted that the surface
carrying the specimens was the upper; whereas the overwhelming probability,
from analogy of similar occurrences elsewhere, is that that the reverse is true.

CONCLUSION AS TO CAMAROCRINUS

While, therefore, there can no longer be the slightest doubt that the
objects known as Camarocrinus were the bulbous distal ends of the stems of
Scyphocrinus, it is obvious that with the foregoing fact established as to the
position of these bulbs, the theory that they served as a float loses much of its
force. That supposition, always at best a somewhat forced one, is no longer
necessary, since the upright position of the bulbs is perfectly consistent with
the simpler and more natural idea that they served merely as enlarged roots,
by which the crinoids were permanently or temporarily fixed to the sea bottom.
The fact that these bulbs are often found in large beds without other accom-

10 SMITHSONIAN INSTITUTION

panying remains does not conflict, as this would only mean that when the
crinoids perished any moderate current would carry away the crowns and
stems, leaving the large roots more or less imbedded in the mud where they
_ grew, as already explained.

There was a tendency among some Paleozoic crinoids to enlargement of
the root, by which the terminal stem-branches were connected by a secondary
growth of calcareous matter, sometimes forming a mere flat-bottomed encrust-
ing mass adherent to other objects, and sometimes a complicated discoid body,
full of chambers or channels, resting in the mud. Such, for example, was the
Astroporites ottawensis described by Dr. Lambe * from the Trenton of Canada,
which I have found both attached to the rock and bedded in soft shale with the
lower surface undifferentiated. Dr. Sardeson* has described various forms
of such discoid roots, to which he has given the name Podolithus; and of which
he considers Camarocrinus to be a modified form. He traces its probable
origin by the aid of an interesting series of figures, supposing the spheroidal
mass to have ultimately become free, and to have floated in an inverted position.

In another case the terminal stem-branches form a rounded mass, with
lateral, hook-like projections which would admirably serve the purpose of a
grapnel or anchor; hence these bodies have been named Ancyrocrinus. But
no one knows to what crinoid they belong, as, though occurring quite abun-
dantly in the Hamilton beds at the Falls of the Ohio and elsewhere, no calyx
has yet been found associated with them. The statement sometimes made
that they belong to Myrtillocrinus is without the slightest authority. A more
plausible supposition would be that they belong to Arachnocrinus, which has
a similar quadripartite canal, and one species of which occurs in the same
horizon. Ancyrocrinus is found in the Hamilton of Clark County, Indiana;
Erie County, New York, and at Thedford, Ontario; but no authentic case of
it in the Onondaga. Myrtillocrinus occurs only in the Onondaga; Arachno-
crinus also occurs in the Onondaga of New York, and chiefly in that formation
at Louisville, Kentucky; but one species—very rare—occurs in the Hamilton
at the latter locality. Except this last, no calyx having a quadripartite stem is
known from the Hamilton of this country.

Other singular modifications in the distal growth of the stem are known
among fossil crinoids. Aspidocrinus Hall, a circular disk with radiating ribs

*Canadian Record of Science, Jan.-Apr., p. 287, 1896. Also F. Springer, Geol. Surv. Canada,
mem. 15-P (Trenton Echinoderm Fauna at Kirkfield, Ont.), p. 46, 1911.

*Journal of Geology, vol. 16, pp. 239-254, 1898.

* Hall, 15th Rep. New York State Cabinet (1862), p. 117.

“Springer (New American Fossil Crinoids), Mem. Mus. Comp. Zool. Harvard, vol. 25, no. 3,
p. 122, I9QII.

* Nat. Hist. New York, pt. 6, Pal. vol. 3, p. 122, pl. 5, figs. 15-20, 1859.

CRINOID GENUS SCYPHOCRINUS II

and wavy edge, is one. Lichenocrinus Hall, which Schuchert * says “ represents
the nearest approach of a modified crinoid root to Camarocrinus,” is another.
This curious disk-like body, composed of numerous rounded plates, has been
the subject of much discussion, but is now known to be the encrusting root of
a very small crinoid of the Heterocrinus type. Specimens with long stems
attached were figured by Meek, but not until recently has evidence of the
associated crown been obtained. This important discovery was made by
Dr. George M. Austin, of Wilmington, Ohio, who has generously placed his
material in my hands for description.

An analogous type of growth is seen in Edriocrinus, which has no stem,
but either is attached to other objects directly by the encrusting base (like the
Recent genus Holopus), or becomes free with the base rounded or extended
downward by secondary growth into a large, conical mass which might have
rested on the sea bottom or might have been moved about by currents.

That Camarocrinus is rounded and somewhat smooth below is not an
objection to the view that it served the function of fixation of the crinoid in
the mud. A perfectly analogous case may be seen in the living Alcyonarian
polyps, the Pennatulids, which have a very similar kind of bulbous root by
which they are habitually fixed to the bottom. In fact, a species of Pennatulid,
Umbellularia encrinus (Pennatula encrinus of Pallas), was treated by Ellis * in
1753, and by authors generally down to Lamarck as analogous to the stalked
crinoids. To show the resemblance of its permanently fixed root to the bulbous
Camarocrinus, I give herewith a photograph of a specimen of the Pennat-
ulid, Ptilosarcus brevicaulis Nutting, from Cape Tsiuka, Japan, 44 fathoms
(No. 30057 of the National Museum collections. Pl. VII, fig. 5). The exterior
of this bulbous root is smooth, as is that of Camarocrinus. Some forms of
Pennatulids have a long slender stalk with a root much more elongate than this,
but still of an essentially bulbous type. It is further significant that among the
Ccelenterates are found the same three modes of attachment as in the crinoids,
namely, by branching roots, flat disks, and bulbs.

Many such enlarged roots of marine organisms tend to develop some kind
of septa or partitions for greater rigidity, dividing them into chambers of more
or less irregular form and size. This is the case in Camarocrinus, where the
chambers are formed of walls which in large part seem to be double in the cross-
sections, as will be explained farther on. When the specimens occur in beds
by themselves, without other accompanying remains of the crinoids, they are
usually rotund, solid, and heavy; whereas when mingled with the stems and

*24th Rep. N. Y. St. Mus. Nat. Hist., p. 216, pl. 7, figs. 1-7, 1872; Meek, Geol. Surv. Ohio, Pal.,
vol. 1, pp. 44-51, pl. 3, figs. 1, 2, 1873.

2 Op. cit., p. 268.

* Nat. Hist. New York, pt. 6, Pal., vol. 3, p. 143, pl. 87, figs. 1-22, 1859.

“Philosophical Transactions, vol. 48, p. 305.

3

I2 SMITHSONIAN INSTITUTION

crowns, as in the recent discovery, they are more or less fragile, flattened, or
broken. This means that in the former case the bulbs, with the crowns and
stems swept away by currents, were left resting in the mud, where they
remained but little disturbed during fossilization until the organic soft parts
were replaced and the cavities filled by limestone or silica, like those of shells;
while in the latter they were distorted or broken by the weight of the other
remains piled upon them before they had time to solidify.

Upon the evidence of all these new facts, I think it may be considered that
our knowledge of the bodies called Camarocrinus is advanced to the extent of
proving that they belong to the genus Scyphocrinus, of which they formed the
bulbous distal end of the stem, having the functions of a root, and fixing the
crinoid habitually to the sea bottom.

After the first draft of this paper had been read before the Paleonto-
logical Society in December, 1912, and the first six plates to illustrate it pre-
pared, I learned from Dr. August Foerste that he had found some other crinoid
remains associated with the Camarocrinus at one of the Hardin County locali-
ties mentioned in his paper of 1903, before referred to, and he very kindly
sent them to me for examination. They proved to be fragmentary specimens
of two or three species of Scyphocrinus. As this is the region from which the
type of Scyphocrinus prattent was probably derived, and as the Camarocrini
collected by Dr. Foerste were in an unusually fine state of preservation, this
occurrence suggested the possibility of further discoveries, and I decided to
defer publication until I could have the territory carefully examined, in the
hope of obtaining better material for the illustration of the Tennessee species.
For this purpose I was so fortunate as to secure the cooperation of Prof. W. F.
Pate, of Kentucky, who had in former years made some remarkable collections
for me in the Tennessee Silurian’ and whose intimate acquaintance with the
Silurian and Helderbergian formations of that region renders his assistance
especially valuable. He spent nearly a month during the summer of 1915, and
further time in 1916, chiefly in Hardin County, with extraordinary results.

Mr. Pate readily identified the Camarocrinus horizons mentioned by
Foerste’* at localities on Horse Creek and at Pyburn’s Bluff, and traced the
finely preserved specimens to the layer producing them—a great bed filled with
Camarocrinus, but no other fossils except a few adhering to the bulbs. This
layer is composed of a rather friable, highly siliceous clay, interbedded among
a series of white limestones, and is the mud bed in which the bulbous roots once
rested on the sea bottom. Here the Camarocrinus occurred in great numbers,
firm, rotund, showing the irregularly plated surface of the bulbs in nearly their

*Journal of Geology, vol. 11, p. 683.
*The Late Niagaran Strata of West Tennessee, Pate and Bassler, Proc. U. S. National Museum,

vol. 34, p. 407, 1908.
"Op. cit. pp. 682-685.

CRINOID GENUS SCYPHOCRINUS 13

original condition, and little altered by chemical or other action, except in the
way of silicification and the filling of the cavities with solid matter. A repre-
sentative series was selected ranging from 25 to 110 mm. diameter, all with the
stem attachment and roots ramifying downward into the spheroidal mass,
surrounded by the peculiar projecting collar mentioned by Schuchert.’

Except when adhering to them by growth, no other remains of Scypho-
crinus or other crinoids were found associated with these bulbs. To some of
them are attached bryozoa, small brachiopods, the base of a small species of
Edriocrinus, and certain roots representing young stages of the Camarocrinus
hereinafter described; these are usually confined to mature specimens. In
others the surface is free from foreign organisms, being entirely composed of
irregular, polygonal plates, as illustrated by Schuchert in his plate 40. Such
individuals had probably been completely buried in the mud. The important
fact in this connection is that no other remains of this large colony of adult
crinoids were to be found in the deposit. It is thus evident that the crown and
stems belonging to them had been swept away, leaving the bulbous roots
imbedded in, attached to, or resting upon the mud, where their cavities became
filled with matrix and solidified by infiltration of mineral solutions. Contact
with the sea bottom might in many cases have been by a small area, leaving
much space for attachment of bryozoa and other adhering forms; and no doubt
some of the bulbs became dislodged by various agencies. The mode of occur-
rence at this locality is about the same as that described by Schuchert (op. cit.,
p. 263) for the occurrences in Oklahoma, as is shown by a large collection from
that field in the National Museum.

There are other Camarocrinus horizons in this region, as stated by Foerste,
and in these the bulbs are associated with the calices and stem fragments of
Scyphocrinus, usually in hard or cherty limestone, with occasional partings or
pockets filled with clay. Many of the remains in these beds are much disturbed,
broken, and intermingled. The bulbs are often crushed, some adherent to
calices (Pl. VII, figs. 2a, b); and both more or less encrusted with bryozoa—
showing that the organisms had been washed out of their original bed and
moved about upon the sea bottom before final deposition in the limestone
sediment. Some of the bulbs in this condition are geodized, and lined with
quartz and calcite crystals. No crowns were found intact, and in only a single
instance was any part of the arms preserved.

At five localities the calices occurred in considerable numbers, belonging
chiefly to two extremely well-marked species heretofore unrecognized in the
genus, and strikingly different from those of the Scyphocrinus elegans type.
These are the S. pratteni of McChesney, described from an imperfect calyx,
whose important characters have not heretofore been understood; and a fine

1Op. cit. p. 263, pl. 41, fig. 1.

14 SMITHSONIAN INSTITUTION ~

new species, S. pyburnensis. The former is remarkable for its extraordinary
size, being among the largest of known crinoids; and in both is presented a
new phase of crinoid morphology, in that the calyx is lobed by the protuberance
of the interradial areas instead of the radial. Some of the specimens are very
well preserved as to the calyx, and show the fixed pinnules of the interbrachial
pavement more plainly than is seen in the Cape Girardeau species. A third
species, S. mutabilis, of the elegans type, is well represented, and it also occurs
in Perry County and other localities to the north. The associated Camaro-
crinus bulbs and Scyphocrinus calices in this new material confirm most beauti-
fully the observations before made as to the relative size of the stem at the
proximal and distal ends, as will be shown further on. All these occurrences
are in the Ross limestone of the Linden formation (Helderbergian), which has
a thickness of more than 100 feet in two principal Hardin County areas,
Pyburn’s Bluff on the Tennessee River and Horse Creek to the eastward. There
are several beds of white, blue, and cherty limestones. The great Camarocrinus
clay bed is included within a series of white limestones in the lower part of the
formation in the Horse Creek area; these are followed by about 60 feet of hard
bluish- to yellowish-brown cherty limestones, disintegrating occasionally into
clay pockets, and in the upper 25 or 30 feet of these cherts is found the
S. prattent. S. pyburnensis occurs at the Pyburn Bluff area through about
35 feet of bluish-grey and cherty limestones, in the lower part of the formation
down to the water’s edge. Here the prattent beds are not exposed, and the two
species are not found in the same horizon or locality. S. mutabtlis occurs in
both areas, probably concurrent with the other two species.

So far as observed, the crinoids, both Camarocrinus bulbs and other
remains, occur rather indiscriminately throughout their respective limestone
and cherty strata, and not in a single clearly defined horizon as in the lower
clays.

CONSTRUCTION AND PROBABLE ORIGIN OF THE BULBS

Before proceeding to consideration of the species, it may be well to present
the result of studies upon the mechanics of these singular root structures.
Schuchert’s description, slightly condensed (op. cit., pp. 263-264), is as follows:

Inside of the bulb is a large, more or less pentagonal, medio-basal chamber, around
which are usually arranged five or six, and more rarely as many as II, variously shaped
chambers. The walls of the camarz have their origin in bifurcations of the roots beneath
the stalk. The walls of the chambers are double, and are made up of small, irregularly
shaped plates. Each lobe has a large opening leading to it from the axil of a root
bifurcation. The inner walls are surrounded by an outer integument of innumerable small
plates, devoid of regular arrangement. The origin of this outer wall is independent of
the roots. At the stalked end of the bulb is a projecting collar which bounds the area
occupied by the visible parts of the branching roots. Around the inner side of this collar,
and in the forks of the last visible bifurcations of the roots, are the openings into the

CRINOID GENUS SCYPHOCRINUS 15

chambers, there being thus as many openings, and as many chambers, as there are
ultimate root bifurcations inside the collar. The area within the collar is composed of
two sets of plates—one series consisting of larger pieces, fairly regularly arranged, and
restricted to the roots that radiate from the stalk; the other, of irregularly shaped smaller
pieces that fill in the spaces between the root radii. The axial canal of the stalk does
not pass through the base of the bulb and into the medio-basal chamber, but ends in the
primary root member, where it branches and connects with the canals of all the roots.
The latter canals pass through all the bifurcations and continue into the outer wall com-
municating with the open space between the two parts of the walls. In this way vascular
and nervous connection is maintained between all parts of the bulb. [See Schuchert’s
figures, op. cit., p. 264, text-fig. 43; pl. 41, figs. 1, 3; pl. 42, figs. 3, 4.]

This description is copied nearly verbatim, and except as to certain points
now better understood it is in the main substantially correct; it may now be
supplemented by the results of further information. Each pair of roots of the
peripheral dichotom within the collar divided further into numerous ramifica-
tions which were connected with each other by growth of undifferentiated
plates, producing a pair of curving, leaf-like extensions comparable to the con-
solidated rays of Crotalocrinus, which progressively met by their edges and
fused, forming a short, tubular opening which expanded into an ovoid sac,
composed of a single wall. Thus arose a circlet of four or more large sacs,
suspended from the edge of the pavement-like area bounded by the collar, and
mutually in contact toward the center. A polygonal space was left at the center
between the sacs, which is the “ medio-basal” chamber of Schuchert, as shown
by his figure 4 of plate 42; in this there are five sacs, with the openings toward
the stalked end away from the observer, not shown in the figure owing to the
deep shading.

Meanwhile other systems of plates derived from the principal root members
extended themselves by continuous multiplication in different directions so as
to form: (1) a projecting collar bounding the area occupied by the sac open-
ings and the root members leading to them; (2) a connecting pavement between
the root members within the collar; and (3) a wall enclosing all the sacs and
constituting the outer wall of the bulb as now seen. The last is also a single
wall. But wherever it touched the walls of the sacs, or wherever the walls
of two sacs came together, there, and only there, do we find a double wall. See
Hall’s figure 7 of plate 35 of the 28th Report, where in a cross-section the
walls of the sacs appear single around the “ medio-basal ”’ chamber, and become
double in the partitions where those of two sacs meet and where the latter meet
the exterior wall. These different walls are not independent structures, but
all have a common origin, being derived directly from the ramification and
inter-connection of the roots; and they are innervated by a common nervous
system. It is probable that the openings leading to the sacs were closed in
life by some kind of membranous structure, as no foreign objects are found
within the chambers except homogeneous matrix deposited during fossilization.

16 SMITHSONIAN INSTITUTION

As a result of these facts the bulbous root of Scyphocrinus (Camaro-
crinus) may be definitely characterized as follows:

A rigid, hollow, chambered root, consisting of a large spheroidal bulb with
a short projecting collar; a stem base with bifurcating roots resting in and
forming a large part of the floor within the collar; and several internal,
laterally apposed sacs which abut against the inner side of the bulb wall and
open separately to the exterior by large channels located between the collar
and the axils of the peripheral root branches; the whole innervated and nour-
ished by incorporated nervous and vascular systems. Within the collar are
the stem base, its proximal bifurcating roots, and a single floor-like layer of
root plates formed by the branching and union of lateral rootlets. The collar
and bulb wall consist of single layers of similar plates derived from rootlet
systems originating at the ends of the proximal root branches, some turning
upward and uniting to form the collar; others turning downward and similarly
uniting to form the bulb; while still others, springing from the root axillaries
and laterally coalescing, produce the internal sacs. The neurovascular systems
passed downward in the stem through the roots and out into the various rootlet
walls, forming a reticulated network of surprising magnitude which innervated
and nourished each plate of the root.

The wall structure as above described, the origin and position of the sacs,
and the relation of the collar and floor to the other walls, are illustrated by the
generalized figure (text-fig. 1), constructed by Mr. Wilson from sectioned and
fractured specimens in the collection, by which these details are fully disclosed,
and by other figures in connection with it. One of the most instructive of these
is text-figure 2, showing a part of the collar in which the plates have separated
along the suture lines; the striated joint faces of the plates and the pores for
the nerve cords are perfectly visible; and it is interesting to note how the upper
or finishing row of plates, being rounded except where in contact with the row
below it, resembles a strong root built up of radiately striated, discoid ossicles.

In connection with the development of the root branches are some further
curious facts. Sehuchert (op. cit., p. 264) noted that “the stalk is generally
placed a little eccentrically to the high, most prominent, or primary root
member.” This is shown by his figure 43 on the same page; and in that, as
well as in figure 44, may be seen a low, rounded cusp near the base of the stem,
projecting from a root branch that is decidedly larger than the others. This
cusp appears to be the remnant of what was the pointed distal end of the larval
stem before its attachment to the sea bottom; and its position results from the
fact that the branching of roots was not symmetrical, but took place at one
side because the young stem, too thin and pliant to attach itself at the extreme
point, made its lodgment at a curve a little way above, so that the stem at
that place was for a short distance recumbent. Thus the terminal point of the

CRINOID GENUS SCYPHOCRINUS 17

young stem was in many cases not attached or imbedded, but remained project-
ing above the general level of the roots, where it underwent a process of
gradual suppression and disappearance, frequently leaving a scar which is to

Fics. 1-2

1. Bulbous root (Camarocrinus) of Scyphocrinus. Generalized figure constructed from
sectioned and fractured specimens in the author’s collection. Showing the relation of the
stem and its outgrowths, viz., the pavement, the bordering collar, the branching roots and
sacs suspended from them with openings upward, all formed by extension and multiplica-
tion of root branches. Perforations for nerve cords may be seen on the exposed faces
of plates. Nat. 2. Part of fractured collar belonging to a large bulb, used in constructing
peel the plates have separated along the sutures, showing perforations for nerve
cords. X %.

be seen close to the stem upon some very mature specimens (see Hall’s
fig. 5, pl. 36, 28th Rep. N. Y. St. Mus. Nat. Hist.). Concurrently with this
process the stem in the opposite direction gradually changed its position from

Fics. 3-6

Stem and roots of Scyphocrinus, merging in bulbs not shown. Showing stages in
reduction and disappearance of primary terminal root at a, from a projection of several
segments with stem partly recumbent (3), to a mere flat scar with stem erect (6). All x 2.

recumbent to erect, the latter being often not attained until the projecting point
or cusp had disappeared.

Text-figures 3, 4, 5, and 6 show some of the stages of fixation of the stem
and disappearance of the terminal point.

18 SMITHSONIAN INSTITUTION

The first developed, or primary, root member usually took the same direc-
tion as the original point, and became the largest; it might divide and sub-
divide into strong branches at whose axils were formed one or two of the
openings and resulting sacs. Two to four other strong root members are given
off toward the opposite side of the point of attachment, forming with the
former ones the primary sacs; these may be followed by other and younger
roots giving rise to successively smaller sacs which lie around the upper
periphery of the bulb, but usually do not extend to the middle or lower zone.

Such a one-sided growth of root branches is not uncommon. It appears
in numerous unconsolidated roots of an otherwise unknown crinoid of the same
formation; and the same thing occurs in the Recent genera Rhizocrinus and
Bathycrinus, and probably in many forms which are fixed to the sea bottom by
delicate branching roots (see P. H. Carpenter, Challenger Report, Stalked
Crinoids, pl. 7, fig. 1; pl. 9, fig. 1).

This mode of distribution of the roots may explain the further curious
fact that whereas the axial canal in this genus is pentapetalous, the number
of principal chambers or sacs in the bulbs is usually not five, but four; addi-
tional ones irregularly, and occasionally to a total of 10 or 11, may develop
from younger roots, as already explained, or from further bifurcations. There-
fore, while a cross-section near the stalked end of a bulb may show eight or ten
chambers, a section taken toward the other end will usually have but four.
This is finely shown by figures 1, 2, 3 of Schuchert’s plate 44, giving three hori-
zontal sections at different levels in the same specimen, the upper two having
eight chambers, while in the lower one the number is reduced to four large
chambers with a faint remnant of a fifth. In three other specimens sectioned
above the middle there are four large chambers and two small ones. The weath-
ered specimen figured by Schuchert on his plate 43, and the section in Hall’s
figure 8 of his plate 35, show the four primary chambers as they will be found in -
probably 90 per cent of the specimens at a level in the lower third of the bulb.
Hall’s figure 1 of the same plate shows how there were four principal lobes,
with smaller ones added at the top. They are always unequal; sometimes one
is much larger than the rest, and sometimes three are large and one small.
Other irregularities are seen in Hall’s figures 3 and 7 of his plate 35. Where
there is a considerable increase in number of chambers above four or five, it
will usually be found that they are developed along the recumbent part of the
stem, or the primary member, as a sort of axis, instead of in a symmetric
radiation from a central stem. This is excellently shown by Schuchert’s
figure 3, plate 42, and Hall’s figures 1 and 3, plate 35.

Finally, we have some interesting information as to the growth of the
roots, derived from young specimens which have lodged upon the hard surface
of mature bulbs and become fixed to it. Being unable in this situation to

CRINOID GENUS SCYPHOCRINUS 19

develop according to their tendencies, the roots, instead of spreading symmet-
rically as is usual with encrusting roots, assumed most irregular shapes; in
some, relatively long branches are grown all on one side (text-figs. 7, 8) ; in
others, lateral connection has produced a flat plate for a certain distance mostly
on one side, beyond the edge of which the branching roots become separate
again (text-fig. 9); in a case still further advanced, a flat plate has been
formed with a similar one-sided growth which has followed the course of the
recumbent stem for a considerable distance, the stem being as it were half
buried in the plate (text-fig. 10). In this specimen some of the root branches
are partly separated from the floor, as they are occasionally seen within the
collar in the regular bulbs.

Fics. 7-10

Roots of young specimens of Scyphocrinus attached to hard surface of mature bulbs,
developing unsymmetrically and chiefly toward one side: 7, 8, long branches, X 2; 9, flat
plate followed by small branches, < $; 10, flat plate with similar one-sided growth follow-
ing course of recumbent stem, X 3.

These remains are not at all common considering the number of bulbs in
the collection, and it seems probable from the rounded appearance of the stem
joint-face where detached that the young did not long survive their fixation
in so unfavorable an environment.

MODE OF UNION BETWEEN PLATES IN SCYPHOCRINUS

Examination of the material in hand has yielded some information as to
the union between the various plates. Superficially each suture appears as a
fine denticulate line, formed by the interlocking of closely spaced crenule on
the apposed plate facets. In the calyx the facets usually consist of two or
more distinct areas for the insertion of ligaments. The first is a narrow,
usually continuous, often convoluted, band surrounding one or more depres-
sions, and forming the contact surface of the plate. The second area or areas
consist of the depressions or ligament fossee. The surface of each facet is
crenulated, the crenulz originating in the deepest portion of the ligament
fosse, radiating outward and crossing the contact band at right angles. The

4

20, SMITHSONIAN INSTITUTION

distal facets of the basals have single, deep, inwardly sloping fossz (text-
fig. 11). The proximal facets of the radials have single, very deep fossz
corresponding in outline to those of the basals, but with their floors divided
into a lateral series of conical pits from which the crenule radiate (text-
fig. 12). The facets of the primibrachs, lower secundibrachs, and inter-
brachials show still further modification, the walls of the pits having thickened,
and increased in height until they came into contact with similar walls in the
apposed facets. The contact areas between the upper portions of the small
ligament pits are usually deeply lobed by the depression of the surface along
the plate margins, thus forming a series of external pits between the plates,
and leaving the ligament fossz surrounded by narrow contact bands which

Fics. 11-16

Mode of union between plates in Scyphocrinus. 11, distal face of BB. 12, proximal face
of R. 13, distal face of IBr. 14, distal face of higher IIBr. 15, 16, distal and lateral faces
of TITBr;” All’ X 4:

project outwardly at right angles from the internal marginal band as a series
of loops (text-fig. 13). The facets of the higher secundibrachs have single,
deeply inward sloping fosse surrounded by a broad, smoothly outlined mar-
ginal contact band (text-fig. 14), but in the tertibrachs the fossa become
very shallow, merging imperceptibly with the contact band of the outer margin,
and in some examples completely surrounding the plates near the inner margin
of the inner contact band (text-figs. 15, 16).

This is a type of loose suture formed largely by interlocking crenulations
admitting slight mobility, similar to that between the usual discoid stem ossicles,
associated with a more or less pliant tegmen of undifferentiated small plates,
occurring in forms like Reteocrinus and Glyptocrinus, which exhibit variation
from the Camerate calyx toward that of the Flexibilia.

The internal surface of the calyx plates of Scyphocrinus is ornamented by
fine strize arranged at right angles to the sutures, forming trapezoidal areas

CRINOID GENUS SCYPHOCRINUS 21

coinciding at the plate angles, with or without folding of the surface (PI. VI,
figs. 18, 19). The fine, low ridges which cause the striation of the surface
terminate in the marginal crenule, and are apparently formed by the contin-
uous growth of the crenule during lateral increase of the plates. The internal
folds have no relation to the external folds or the ligament fosse, and their
purpose is doubtful.

The stem facets of Scyphocrinus are circular, the contact area narrow,
sloping gradually into the ligament fossa, with radiating crenule passing nearly
to the center (PI. V, figs. 2-5). In the root bulb (Camarocrinus), the plate
facets are slightly concave, and the crenule radiate outward from the central
axial canal (text-fig. 2).

THE AMERICAN SPECIES OF SCYPHOCRINUS

It is an interesting illustration of the progress of discovery, and of the
liability to change of opinion resulting therefrom, that this genus, so profusely
illustrated by Waagen and Jahn, and supposed by them as well as by Schuchert
to be unknown outside of Bohemia, now proves to be more widely distributed,
and represented by a far greater variety of species, in America than in Europe.

The genus Scyphocrinites was proposed by Zenker’* in 1833, based upon
specimens from Bohemia which he described under the name Scyphocrinites
elegans, which should therefore be the type. Schlotheim had previously, in
1820, applied the name Pentacrinites excavatus to certain specimens said by
him to be the “ Prague Encrinite,’ and to figure 2, plate 4, of Schroeter’s
Vollstandige Einleitung, 1778, but without other description. Passing over
various allusions to these fossils in the intermediate literature, we have as the
chief source of technical information the elaborate work of Waagen and Jahn
in 1899, based partly upon the unpublished researches of Barrande.’ Some 22
large quarto plates, with voluminous text, are devoted to the illustration and
description of the Bohemian forms of this genus, including a complete résumé
of antecedent literature.

For the purposes of the present paper Scyphocrinus may be briefly defined
as a Melocrinoid, with four basals; with branching, uniserial arms; and with
some of the tertibrachs, and perhaps higher brachials, incorporated in the
dorsal cup by means of a network or pavement of plates connecting those of
adjacent rays. This pavement is the most conspicuous feature of the calyx,
producing depressed, numerously plated, interbrachial areas above the level
of the axillary primibrachs, peculiarly modified by secondary growth, with

*+Since their work appeared, fragmentary remains of Scyphocrinus and Lobolithus have been

Bie from Cornwall, England, and also from Poland, Prussia, the French Pyrenees, Spain, and
ndia.

? Beitrage zur Naturgeschichte der Urwelt, p. 26.
° Systéme Silurien du centre de la Bohéme, vol. 7; Scyphocrinus, pp. 35-97.

22 SMITHSONIAN INSTITUTION

the arm-bases strongly elevated between them. Stem round, long, terminating
in a large, spheroidal, chambered body, having the functions of a root.

The literary status of the most important described species is unsatis-
factory. Messrs. Waagen and Jahn profess themselves unable from’ the
works of these authors to identify with certainty the two species of Zenker
and Schlotheim, and while in one place retaining the name elegans as a term
of convenience for a group of species, they ignore it as the name of the type
species, but assign excavatus to a form which they redescribe as probably
including that of Schlotheim and three new varieties. They also describe
Scyphocrinus subornatus of Barrande (MS.), and another new species of their
own, S. decoratus.

This course of the authors as to the type species was criticized by Bather *
in 1900; but while for the purpose of a review he might afford to accept it
“ for the sake of concord,” that cannot be done in this paper, which has to deal
with important new material for which a correct name is required. Zenker
gave both a description and recognizable figures of the form to which he
applied the name elegans. As to this Waagen and Jahn say, on p. 42: “The
description of Scyphocrinus elegans Zenker agrees perfectly with the greater
part of the specimens which we arrange in three new varieties: Scyphocrinus
excavatus var. typ., var. Schlotheimi, and var. Schroeteri; there is also a
remarkable agreement between the specimens and the figures given by Zen-
ker”; on the other hand, “the species of Zenker differs notably from the
crinoids * * * described by Barrande under the name S. subornatus and by
us under the name S. decoratus and S. excavatus var. zenonis.” But having
observed among their material several varieties no particular one of which
is indicated by the earlier figures, they conclude that “we cannot then apply
to our specimens either the name excavatus Schlotheim, which has priority,
or that of elegans, given later by Zenker; but from respect to the memory of
our predecessor we designate one of our species by the name excavatus.”’ And
this they proceed to do throughout, citing the species as of ‘‘ Schlotheim sp. p.”’
Now Zenker’s figures and description, instead of mere arm fragments like
those of Schroeter to which Schlotheim gave his name, were based upon speci-
mens quite sufficient to afford a generic diagnosis, and to show that the species
for which they formed the types is the one characterized by sharply sculptured
plates. The species S. excavatus, as described by Waagen and Jahn, is con-
fessedly not identifiable from the works of Schlotheim, and for the purposes
of credit it must date from Waagen and Jahn, 1899. Therefore Zenker’s prior
name, elegans, must hold for those forms which they admit to agree with his
description and figures—leaving excavatus to stand, if at all, for their variety
genonts, which they say does not so agree.

4Ann. and Mag. Nat. Hist., vol. 6, July, p. 115.

CRINOID GENUS SCYPHOCRINUS 23

On p. 77, as a result of a general discussion of the species, they arrive at
the following arrangement:

From what we have said it results that among the forms of Scyphocrinus there are
only three which can be exactly defined ; these are:

1. S. subornatus Barrande.

var. zenonis W. and J.
var. schlotheimt W. and J.
var. typica W. and J.

var. schroeteri W. and J.
3. S. decoratus Waagen and Jahn.

2. S. excavatus Schloth. sp. p.

As to the forms comprising no. 2 they say: ‘‘ We are constrained to con-

sider them all four only as varieties of a single species, Scyphocrinus excavatus
Schloth.”

It will be observed that while in the last arrangement they place their
variety zenonis along with the other three in a specific group distinguished
from that of S. subornatus, in the first arrangement, on p. 42, they consider
it as “differing notably” from those three. In my view of the relative
importance of the characters as elsewhere stated by them, it would be more
consistent to leave genonis as a separate species, and perhaps to place decoratus
with the other three as a variety.

Waagen and Jahn were much impressed by the singular conformation of
the interbrachial pavement, and through lack of understanding of its relations
were led to attach undue importance to its variations when disposing of zenonis.

Conformably to the above suggestion, the following summary made from
their detailed descriptions and figures, as well as from my own observations,
will show the characters and relations of the Bohemian species; they are
taken in reverse order for better comparison:

I. Group elegans: Calyx plates sculptured.
Species 1. S. elegans Zenker (excavatus W. and J., pars).

Calyx elongate, obconical, of medium size to very large. Plates in
lower part low-convex, with several fine, continuous, parallel ridges of
coste radiating from near the center, crossing the sutures and connecting
from plate to plate, forming triangular or rhombic figures. Interbrachial
plates are not recognized higher than four ranges, it being considered that
above that they are so small, and their sculpture so strong, that it is difficult
to distinguish their contours, and that their arrangement is generally
irregular. In the interbrachial areas from about the zone of the first
secundibrachs the ridges either tend to coalesce into single, strongly raised,
wide or narrow bands crossing the sutures with sunken areas between,
giving a more or less reticulate, cancellate, stellate, or transversely banded
appearance; or they may disappear, leaving the plates of the pavement
smooth or granular, flat or greatly rounded. These ridges are more con-
spicuous toward the margin of the plates, where they sometimes form a

24 SMITHSONIAN INSTITUTION

sort of crenulation; toward the center they are frequently somewhat
effaced. This plate sculpture is all a modification of a single plan; the
different varieties depend upon the degree to which the union and enlarge-
ment of the radiating coste proceed, and they may all be more or less
present in the same specimen. Some of the specimens have the brachials
beyond the lower secundibrachs perfectly smooth, others with a strong
transverse ridge, and still others with a girdle of detached granules.

Upon the predominance of the various kinds of plate sculpture in the
interbrachial pavement Waagen and Jahn have proposed the following varie-
ties, which they admit are not constant:

a. Plates of pavement rather irregularly convex in lower part; passing somewhat

abruptly into broad ridges forming several interrupted, transverse bands,
or rows, resembling chains, more or less parallel, arched downward.
var. schlotheimi.

b. Plates of pavement in upper part with more or less deep pits, forming a net-

work of rhombs; in lower part stelliform. var. typica.

c. In lower part a complicated network into which root-like prolongations from

the sides of the lower arm-brachials enter, and from which the arms appear
to rise suddenly, as if they emanated from roots. var. schroeteri.

Comparing the figures, it is impossible to identify these three varieties
with any certainty, as they all run into one another, the characters often being
all combined in one specimen.

Species 2. S. decoratus Waagen and Jahn.

Like elegans, but the radiating coste are formed of separate granules.
Calyx very large.

These characters are found intermingled in my specimens (see PI. II).

II. Group subornatus: Calyx plates not sculptured.
Species 3. S. zenonis Waagen and Jahn.
Plates smooth or granular, convex, with crenulated margins. Pave-
ment as in var. schlotheimi.
Species 4. S. subornatus Barrande (MS.).
Plates smooth or granular, flat or concave in the middle, straight or
irregularly plicated; interbrachial pavement of smooth, flat plates; arm
plates also smooth, and but slightly raised.

To these might be added another variety under S. elegans from a fine
specimen in my collection in which the plates of the iBr pavement are smooth
except for a pustulose center.

All of these species and varieties are derived from the transition beds
between étages E* and E* of Barrande’s section in central Bohemia, hitherto
called Silurian, but which Dr. Ulrich is now inclined to consider as more nearly
equivalent to the lowermost Devonian (Helderbergian) formation of this
country. In view of the recent discoveries in Tennessee, whereby the range

CRINOID GENUS SCYPHOCRINUS 25

of the genus is carried down into undoubted Silurian, it may be that this
correlation should await further revision by the stratigraphists. Although they
figure on plate 44, figure 3, a specimen of S. subornatus with a part of a
Lobolithus in contact, Messrs. Waagen and Jahn nowhere intimate the possi-
bility of their being parts of the same organism. But in 1904, in a letter quoted
in Schuchert’s paper (p. 259), Professor Jahn states that ‘“‘ certain Loboliths
belong to Scyphocrinus,” he having observed them “ connected by long columns
to Scyphocrinus calices.”

I have given the foregoing abridgement of Waagen and Jahn’s definitions
of the Bohemian species for the purpose of comparison with the American
species, in view of the remarkable parallelism that exists between them.

In this country there seem to be at least eight species based upon the
characters shown by the calyx, from four widely separated areas—all of
Helderbergian age; one from the lower, the Keyser beds, and the others from
the higher Linden, Bailey, and Haragan beds, one of which, however, goes down
into the Niagaran. They are divisible into two well-marked groups, distin-
guished by radically different types of calyx. The Missouri form, the only one
of which the arms are fully known, is in size, surface ornament, structural
details, and general habitus so remarkably like the leading Bohemian species
that no reliable differentiating characters can be found in the fossil state.
Most of the others are well characterized.

A further remarkable modification within the limits of the genus is seen
in the presence of articulated spines, as shown in S. spinifer.

The stratigraphic range of Scyphocrinus is considerable, extending from
the Decatur formation of the Niagaran to the close of the Helderbergian in
the Tennessee area. S$. mutabilis occurs in Perry County in a bed of yellow,
granular, crinoidal limestone referred to the Decatur limestone (the highest
member of the Niagaran), associated with the genera Clonocrinus, Desmido-
crinus, Gazacrinus, Eucalyptocrinus, Marsipocrinus, Lecanocrinus, and Piso-
crinus; and another indistinct species along with frequent Camarocrinus has
been found in a hard grey limestone underlying the yellowish layers.

Hence in these beds at the top of the Niagaran, intermingled with its char-
acteristic species, Scyphocrinus begins and from there continues throughout
the Linden to its highest beds in the northern part of Benton County, where
it is associated with Devonian species quite different from those of the other
Linden beds. Among these Devonian forms I have recently obtained a well-
marked specimen of Phimocrinus, the ancestral form of Synbathocrinus, a
genus not hitherto seen in America; and numerous weathered fragments
indicate the presence of a form like Stereocrinus, which would carry the Dola-
tocrinites a stage lower in the stratigraphic scale than has been hitherto known.

26 SMITHSONIAN INSTITUTION

The correlation of the different local formations containing Scyphocrinus,
according to the latest determination of the U. S. Geological Survey, may be
stated as follows:

| | Tennessee Missouri Oklahoma West Virginia
S
Z =
5 $ Linden formation Bailey ls. Haragan ls.
26 f (Ross ls. at base)
Qs S
Ha 3
fa) = Keyser ls.
=
a 5
io BS Decatur ls.
Se ahs
vi z

It is a question how to deal with the described species of Camarocrinus,
now that it is certain that they all belong to the genus Scyphocrinus. The
characters on which they are based, namely, the form and proportions of the
bulbous root and the different conditions of its external surface, are in my
opinion of little or no diagnostic value. The root in Paleozoic crinoids, when
it exists, is a generalized structure, usually not marked by specific differences
(even the stem as a whole having by no means the taxonomic value which it
has in the Recent crinoids); while as to surface characters, the differences
hitherto noted are largely due to chemical action and the effect of weathering.
This is well shown among specimens in my collection from the same locality.
Those which are apparently little altered from their original condition have
a smooth surface, composed of undifferentiated small plates, as shown in Hall’s
figure I of plate 36, in the 28th Report of the New York State Cabinet; if the
calcareous surface of these has been dissolved and the underlying structures
replaced by silica, various sorts of rugosities, more or less regular, will often
appear; e. g., as in Schuchert’s var. stellifer (op. cit., pl. 40, fig. a; pl. 41, fig. b).

The form and number of the lobes into which the bulbs are divided are
variable, and as specific characters these are of no importance whatever.
Usually the chambers developed from the root branches are represented by
more or less protuberant,. unequal lobes. The primary number is four, to
which others may be added to a total of about 11, as already explained; and
exceptionally the number is reduced to three. In case of five lobes, which is
the most frequent variation, the added lobe is usually much smaller than the
original four; a symmetrically quinquelobate bulb is the exception. In many
cases the external lobing is quite obscure, so that the bulb appears almost
regularly spheroidal. These facts are conclusively shown by the series of 70
finely preserved Camarocrini from the clay bed in Hardin County, Tennessee,
already mentioned. They are all from a single colony, found in the place of

CRINOID GENUS SCYPHOCRINUS 27

its original deposition, and undoubtedly belong to the same species. Of these,
46 have four lobes; 10 have four below and five above; 8 have five; 3 have six;
1 has seven; 1 has eight; while 3 have but three; thus 80 per cent have four
primary lobes or less, 11 per cent have five, and 7 per cent have over five in the
upper part. A similar irregularity is observed among specimens from Okla-
homa, and the variable character of the roots and chambers in them is thor-
oughly explained by Schuchert (op. cit., p. 264). Among 45 specimens, 90
per cent have four (or exceptionally three) lobes in the lower part of the bulb;
20 per cent have five at the stalked end, and 12 per cent have more than five.
At both localities the average height and width of the specimens are about as
I to 1.20, a few being as high as wide. The tendency to increase in number of
lobes is greater in the West Virginia specimens, where out of 29 about
80 per cent show more than five at the stalked end (from 6 to 10, or 11); but
nevertheless 70 per cent of the whole have only four lobes or less at the lower
end. The specimens here are also flatter, the average height to width being
about I to 1.40, often I to 1.50; and in no case equal.

Hence while in a large collection of the bulbous roots there may be a
general facies characteristic of some species, this is of little or no value when
judging from individual specimens; and while the facies might distinguish the
West Virginia specimens from those of Tennessee and Oklahoma, as above
shown, it would not distinguish the latter from each other. The only species
that I should undertake to identify with confidence from the bulbous root is
S. pratieni, whose great size is associated with a character in the primary
root member not observed in others.

As a rule, we do not know positively to which form of calyx any one of
the bulbs in the different localities belongs. Nevertheless, it is fair to assume
that a given bulb of Camarocrinus belongs to the calyx found in the same
bed; and in this way some of the specific names already in use may be retained.

Following this course, where practicable, the species may be characterized
as follows:

ANALYSIS OF THE AMERICAN SPECIES
(All from the Helderbergian ; but S. mutabilis occurs also in the Niagaran)

A. Calyx turbinate, expanding to IIBr.
iBr areas not protuberant.
Plates sculptured.
Calyx elongate, very large, height to width about 1.8
to 1; deeply lobed between arm-bases.

Plates thin, low-convex, with sharp costz, either
becoming smooth or passing into coarser orna-
ment above; interbrachial pavement either re-
ticulate, transversely banded, stellate, irregularly
rugose, or smooth.

IIBr about 20; median ridge broad. 1. S. elegans Zenker.
Bailey limestone, Missouri.

28 SMITHSONIAN INSTITUTION

Calyx rather narrowly elongate.
Plates deeply sculptured; with sharp continuous
coste from base up, surmounted with slender
spines.
IIBr about 12; median ridge narrow. 2. S. spinifer n. sp.
Linden formation, Tennessee.
Calyx variable, usually shorter than wide.
Lower part of cup turbinate, with sides usually some-
what convex.
Plates low-convex, usually without strong stellate
sculpture, but with crenulate margins and pits
at corners; rarely spiniferous.
IIBr about 12 to 15; median ridge broad. 3. S. mutabilis n. sp.
Decatur and Linden formations, Tennessee.
Calyx rather short, height to width about equal.
Plates low, more or less rugose, with prominent
connecting ridges alternating with deep pits
above, producing strongly stellate sculpture.
IlBr about 10; median ridge narrow. 4. S. stellatus (Hall).
Keyser limestone, West Virginia.
B. Calyx widest below IIBr, contracting and cylindrical toward
arm-bases.
iBr areas protuberant.
Calyx broad, robust, extremely large, about as wide as
high.
Plates smooth, broadly convex, often obtusely pus-
tulose. iBr areas sharply protuberant and [Br
deeply depressed between them.
IIBr about 12; median ridge broad. 5. S. prattent (McCh.).
Linden formation, Tennessee.
Calyx elongate, large.
Plates strongly convex, with obtuse stellate sculp-
turing, not pustulose. iBr areas obtusely pro-
tuberant.
IIBr 13 to 15; median ridge rather narrow.
6. S. pyburnensis n. sp.
Linden formation, Tennessee.
Plates smooth and flat, some with pustulose center.
Lower part of calyx broadly curving at wide
angle from base.
IIBr about 11; median ridge narrow. 7. S. ulrichi (Sch.).
Haragan limestone, Oklahoma.
Calyx small, spheroidal below IIBr. iBr areas not

protuberant.
Plates gibbous, thick, smooth to obtusely stellate.
IIBr about 11; median ridge narrow. 8. S. gibbosus n. sp.

Haragan limestone, Oklahoma.

The species of group A are directly comparable with the Bohemian forms
of that type; while those of group B are of a facies totally different from any

CRINOID GENUS SCYPHOCRINUS 29

known in Bohemia, and they introduce into the genus a decidedly new form of
calyx. The protuberant interbrachials are a feature thoroughly distinct from
anything heretofore observed in the crinoids; a lobed form of calyx caused
by the projection of the radial or brachial series is common enough, but the
converse condition found here is something quite unique.

The identical occurrence of such a highly specialized species of crinoids
as S. elegans in the two continental areas points to a remarkable parallelism of
formations so great a distance apart. A like close relation has been found
to exist in other fossils, notably among the Graptolites, of which I am informed
by Dr. Ulrich that one species occurring in the Cape Girardeau beds can scarcely
be distinguished from a Bohemian form of the corresponding stage.

30 SMITHSONIAN INSTITUTION

DESCRIPTION OF THE SRECIES

I. SCYPHOCRINUS ELEGANS Zenker

Plates I; IT; III, figs. 1-4; IV; V, figs. 1-5
1833. Scyphocrinites elegans Zenker; Beitr. Naturges. Urwelt, 26, pl. 4, figs. A-F.
1840. Scyphocrinites elegans Zenker; Miinster, Beitr. Petref., pt. 3, p. 112, pl. 9, fig. 8.
1850. Scyphocrinites elegans Zenker; Quenst., Handb. Petref., 621, pl. 55, figs. 1-3.
1852-54. Scyphocrinus elegans Zenker ; Roemer in Bronn’s Leth. Geog., ed. 3, vol. I, pt. 2,

p. 255, pl. 4, figs. 5a, b.

1879. Scyphocrinus elegans Zenker; Zittel, Handb. Pal., vol. 1, p. 372.

1881. Scyphocrinus elegans Zenker; Wachs. and Spr., Proc. Acad. Nat. Sci. Phil., 298
(GRevaePalsy pti, p 124).

1900. Scyphocrinus elegans Zenker; Bather, Ann. and Mag. Nat. Hist., ser. 7, vol. 6, July,

Hated
er (?) Syn. Scyphocrinus excavatus and varieties; WWaagen and Jahn in
Barrande, 1899. Systéme Silur. du centre Bohéme, vol. 7, pt. 2, pp. 80-88.
After the most careful comparison with the prevalent Bohemian form,
not only from the figures and descriptions of Waagen and Jahn, but with four
good specimens of my own from Bohemia, I am unable to point out a single
diagnostic character by which the Cape Girardeau specimens can be distin-
guished from it. In the general elongate form of the calyx (which does not
appear so constantly in Waagen and Jahn’s figures on account of the flattening
of many of the specimens), the extraordinary shortness of the brachials
beyond the secundibrachs, and the sharp sculpture of the lower plates, they are
identical; while substantially every one of the styles of the interbrachial pave-
ment upon which those authors base their three varieties of S. excavatus is to
be found among the specimens in this collection. The parallelism in this respect
is most extraordinary, as may be seen by a comparison of the figures here given
with the preceding description of those structures, and with the figures of
Waagen and Jahn on plates 40 to 60 of their Monograph.
The calyx is quite uniformly large and elongate, being usually from
112 to 125 mm. high, measuring from the base to the fork of the second
bifurcation of the ray, and about 92 mm. in width at the level of about the fifth
secundibrach, where the radial ridge leading to the arms usually begins to be
prominent. Among more than 50 crowns in this collection I have not found any
with calyx shorter than the smaller dimensions above stated ; but there are several
broken, or but partially exposed, which, from the relative size of the stem or lower
plates, must have been somewhat larger. The specimens are usually consider-
ably flattened, but several are sufficiently rotund to admit of accurate measure-
ment; these have been utilized in constructing the restored figure on Plate IV,

CRINOID GENUS SCYPHOCRINUS 31

figure 1, which gives the correct contour and proportions of a full-sized indi-
vidual if undistorted by pressure. The magnificent crown shown by the photo-
graph (Pl. III, fig. 1), reduced to two-thirds natural size in order to come
within the limits of the plate, has the calyx almost rotund, and its surface
ornament in perfect condition. Plate II shows two fine crowns with stems
attached, natural size, exhibiting almost every one of the different varieties
of plate sculpturing.

The surface of the plates to the level of the upper primibrachs, which are
all low-convex and thin, is conspicuously marked by sharp, rather low ridges
or coste, radiating in parallel sets of five or six from plate to plate, crossing
each sutural face at right angles, forming triangular or rhombic striated areas
(Pl. V, fig. 1). Above this the coste progressively coalesce through various
stages to a single narrow ridge, or until they become merely a broad convex
band; or they may sometimes disappear altogether. Between these parallel
sets, or single ridges—that is, at the angles of the plates—there are depressed
areas, or pits, which increase in depth and size concurrently with the coales-
cence of the coste. These various stages of the ridges and pits produce in the in-
terbrachial areas a stellate, reticulate, corrugated, banded, or smooth surface—
sometimes two or more of these kinds of sculpturing appearing in the same
specimen. If the pits enlarge about equally, and the single coalesced ridge
remains narrow, the plates will have a more or less stelliform appearance
(PI. III, figs. 1 and 3); if the ridges become about equally broad, a network is
produced (PI. III, fig. 4); if the pits at the upper and lower angles are most
enlarged, while the ridges develop chiefly in a transverse direction, the result
will be a series of conspicuous, downwardly curved, rope-like bands traversing
the space between the rays (Pl. II, figs. 1 and 2). The condition of wear at the
surface of the plates during fossilization, or perhaps in life, sometimes exposing
subsurface channels, has often much to do with the appearance of the sculptur-
ing. Occasionally the sharp costz on the lower plates tend to become inter-
rupted, leading to rows of fine granular pustules, on which Waagen and Jahn
based their species S. decoratus.

The number of secundibrachs is about 18 to 20, with little variation, being
more regular here than it appears in the figures of Waagen and Jahn, which
show variations of 15 to 25, some of them perhaps due to inaccurate observa-
tion or drawing. In this character the species differs from all the Tennessee
species, which rarely have more than 15 secundibrachs. The lower secundi-
brachs are of about equal width and length; they diminish in length until those
next to the axillary are about five or six times as wide as long, average length
at this level being about I mm. From about the sixth or seventh secundibrach
they gradually become wedge-form, the wider margin supporting a pinnule
which also abuts more or less on the short margin of the alternate brachial;

32 SMITHSONIAN INSTITUTION

as these plates become shorter the interpinnulars disappear, and the pinnules
abut for their entire length (PI. IV, fig. 1). The tertibrachs become shorter still
(about 0.7 mm.), until the thinner margins are knife-like, and there is no
interval between the brachials at their wider sides (Pl. IV, fig. 4). Toward the
distal end of the arms the brachials become relatively longer, so that the
pinnules are slightly separated (Pl. IV, fig. 10). The distal secundibrachs with
which the fixed arms begin, and the succeeding brachials, may be simply convex
exteriorly—the most usual case—or they may have a more or less raised trans-
verse girdle, sometimes beaded. Laterally, the brachials often have small,
buttress-like projections, which sometimes ramify into the interbrachial net-
work, in which the base of the arms entirely disappears, as if ending in branch-
ing roots.

The arms are very strong at their bases, tapering gradually to great
lengths. They are observed in several specimens for a distance of 300 mm.
without reaching the ends; calculating from the taper of the ultimate divisions,
and comparing this with the detached distal portions seen occasionally among
the specimens, it is clear that the arms were often at least 15 to 20 inches long.
They bifurcate at increasing intervals (longest at the inside of the dichotom)
three or four times, and frequently one of the last pair once again, thus giving
from 80 to 120 ultimate arms. The brachials from the tertibrachs up are
exceedingly short and wide throughout; their extreme shortness is a very con-
spicuous feature, probably characteristic of the genus. The arms are highly
rounded dorsally, and have a broad, shallow, ventral furrow, which becomes
more deeply notched distally; the cross-section is more or less crescentic; from
the truncated horns of the crescent proceed relatively large, closely abutting
pinnulars. The form and relative proportions of these plates in the different
divisions of an arm are shown by the series of figures on Plate IV.

There is so little difference between the anal interradius and the regular
areas that it is scarcely noticeable; one more plate in the second or third, and
in the fourth anal range is all that differentiates them.

The interbrachial pavement.—The most interesting morphological feature
of this species is the peculiar interbrachial network, or pavement, connecting
the lower portions of the arms, upon the different aspects of which Messrs.
Waagen and Jahn founded three of their varieties under the name excavatus.
They have described and figured its various forms in great detail (op. cit.,
pp. 63-88, pls. 43-55). These forms are all found to be substantially repeated
in the Cape Girardeau specimens, among which the interbrachial areas are either
(1) smooth (PI. III, fig. 2); (2) studded with more or less stelliform plates
(Pl. III, fig. 3) ; (3) reticulate, with round or rhombic pits (PI. ITI, fig. 4) ; (4)
transversely banded with rounded plates in parallel, crescentic, rope-like rows,
arching downward as if suspended from the arms (PI. II, and PI. III, fig. 4).

CRINOID GENUS SCYPHOCRINUS 33

Waagen and Jahn only recognized interbrachials sensu str. (interradials) up
to the fourth range, of which they describe the succession as being 1-2-3-3
usually in the regular areas, and 1-2 (or 3)-4-4 usually in the anal interradius.
Beyond that they found the plates to be so small, their sculpture so strong, and
their arrangement so irregular, that their contours could not be distinguished
(pp. 69-70). They viewed this part, constituting the pavage and the
réseau, as a structure sui generis, and they wholly failed to understand its
origin or relations. Bather, with his usual clear insight, perceived the probable
significance of this structure, and in the review above cited (p. 116) pointed
the way to its correct interpretation, although the material at his command did
not furnish him the complete solution which is now at hand.

The superficial aspect of these areas is certainly extremely deceptive, the
actual arrangement of the plates being often wholly obscured by the very
conspicuous rugose surface growth. This is especially the case with that type
which takes the form of transverse bands of strongly elevated plates (for ex-
ample, var. schlotheimi W. and J., pl. 44, fig. 1; and herein PI. II, fig. 1; Pl. III,
fig. 4), which while seeming to pass out from the sides of the arms in regular
rows do so ina manner altogether misleading and wholly unlike that of any kind
of branches or elements ordinarily connected with arms—curving downward
instead of up, and being continuous, like ropes suspended from one arm to
another. Nevertheless, the chief component parts of these areas are modified
pinnules, which by the upward growth of the calyx have become fixed as a
part of its solid wall, and thus have lost their original function.

The complete structure and relations of these parts are perfectly shown
by the natural size figure 1 on Plate IV, drawn with great care by Mr. Chapman
chiefly from specimens 4, B, C, of Plate I, and from the original of figure 1
of Plate V. There is a well-marked transition from the finely costate sculpture
in the lower plates, through strongly stelliform plates in the intermediate
region (lower IIBr), to the strong, rope-like bands above. In this figure, for
better comparison, the plates of the pavement in one-half of an interbrachial
and intersecundibrachial area are left in outline, with the interpinnulars dis-
tinguished by diagonal hatching; so that the position and relations of the
pinnules may be seen at a glance. When the arrangement is once understood
it may be readily traced in many specimens; in some, however, the plates have
been so greatly altered by secondary growth that it is very difficult to identify
the pinnules. We have carefully traced the pinnules in a number of specimens,
and find that their relation as shown by these figures is constant and without
exception, save for an occasional abnormal plate. They are well shown in
specimens of S. pyburnensis (for example, Pl. VII, fig. 2b).

The extraordinary modification of the surface by which the outward
semblance of pinnules is thus effaced is produced simply by the development of

34 SMITHSONIAN INSTITUTION

the connecting ridges crossing the sutures from plate to plate, and of the sunken
areas at the angles, forming pits or rhombs between them, as already explained
(Pl. IV, fig. 3). Owing to fixation and loss of function, the shape of the pinnu-
lars is more or less modified and often irregular, which adds to the difficulty
of identifying them. In some cases, the reticulate or banded surface com-
mences abruptly; in others, the sculpturing passes from the finely costate
marking of the lower calyx plates through an intermediate stage of stelliform
plates. This is sometimes much accentuated by erosion of the plates sufficient
to expose strong radiating channels in the substance of the plates crossing the
sutunesa@PINIM, fies 3s Pl V, fie2; Pl. VIM figs, 2a, 0):

Inspection of figure 1 of Plate IV shows that while the relation of the fixed
pinnules to the tertibrachs as stated by Bather is confirmed, there is a further
definite relation, not only with the distal secundibrachs, which he found it not
so easy to trace, but also with the lower secundibrachs, as to which he thought
it probable that the plates uniting them are true interbrachials. As to all these
it now appears that there is a fixed rule in the position and sequence of the
pinnules.

The sequence of pinnules—TVThe number of secundibrachs in these speci-
mens, as already stated, is quite uniformly about 18 to 20. They begin with
fairly large plates, resembling the primibrachs which precede them, with a
gradually increasing rugosity of sculpturing in the first five, beyond which the
surface is usually plain; there is also a gradual diminution in size, and a change
in proportions from about equal length and width in the lowest ones, to that
of extremely short and wide plates above. At about the fifth plate an increas-
ing convexity begins, marking the origin of a strong median elevation which
passes rapidly into the arms. At this point there is always a plainly noticeable
change of direction, or “ jog,’ in the brachials of each ramus toward the
outside of the dichotom (PI. V, fig. 1). Above this the plates rapidly become
shorter and wider, changing from a proportion of about 1:1.6 to about 1:12
next to the axillary; and they gradually become cuneiform and alternating.
This “jog” is a reliable guide in counting the number of secundibrachs in
imperfect specimens; we know that there are always four or five plates in the
series below it. For example, in Plate VI, figure 5d, with only a small fragment
of the ray preserved, we can tell that there were about 16 secundibrachs.

The I1Br: gives off a strong pinnule toward the outer side of the dichotom,
composed of elongate, more or less hexagonal plates extending to the distal
margin of the calyx; I[Br, gives off a similar pinnule to the inside of the
dichotom; IJBrs another to the outside. And from the fifth plate on, alter-
nating from side to side, each brachial bears a pinnule upon its wider end,
which may also abut upon the narrow end of the alternate brachial. The first
three to seven pinnules are more or less separated at their bases by interpinnu-

CRINOID GENUS SCYPHOCRINUS 35

lars diminishing in size and numbers upward; but their more distal parts, and
the whole length of those succeeding them, lie side by side, closely packed,
forming part of the calyx wall, until they gradually lose themselves in the
tegmen. This fixation of pinnules extends throughout the tertibrachs to the
quartibrachs, passing gradually into a free state, the exact limit of which
cannot be seen for lack of sufficient preservation of the tegmen. All these
pinnules are laterally united by what is probably a loose suture, and the plates
composing them, as high up as the distal tertibrachs, are very thick and flat,
forming by their union a strong wall. The proximal pinnular is joined to the
brachial which supports it, and the following pinnulars to each other by a
curved, non-muscular articulation, the remnant of the movable union lost by
fixation.

The free pinnules continue thus alternately, one from each wider end of
the brachials to the end of the arms; they are relatively short, as is the rule
generally in multibrachiate arms, rounded, composed of a few elongate pinnu-
lars; and they lie closely abutting, because of the extreme shortness of the
brachials; distally they become rounded, less closely abutting, and functioning
normally. The relation of these parts is shown on Plate IV by the enlarged
drawings at figures 4 to 10, with further explanatory text.

Thus the law of succession of the pinnules on the secundibrachs is:
2(t5-2)) outer, — 4 (2--4) inner! —*5 outer —-'6 inner, —- 7 outer, andisolon:
It may be expressed by the numeral 24567-+.

This arrangement appears in several of the other species, and is substan-
tially the same as in Melocrinidz, generally where it can be observed. It is
finely shown in the specimen of Glyptocrinus dyeri figured in my paper on
Cleiocrinus, which I reproduce for comparison (PI. III, figs. 5a, b). The suc-
cession of pinnules is the same, 2-4-5-6-7, etc., and their course is much more
plainly defined by the sharp longitudinal ridges. In this specimen the tegmen,
although distorted at one side by an imbedded stem-fragment, is well preserved,
and shows how the fixed pinnules merge into the finely plated perisome, which
passes into the tegmen so gradually that it is impossible to distinguish a
boundary at which the pinnules should become free. In a similar manner the
ridge-like series of anal plates is seen bending over, probably to a small central
opening. The same plan of tegmen structure no doubt existed in Scyphocrinus,
in which this part has not yet been found intact.

The sequence above described is also precisely the same as that of the
fixed pinnules in Uintacrinus, except that in the latter the plates 6 and 7 form
a syzygial pair, the pinnule being borne only on the hypozygal there as well as
in the higher parts of the arm. In Scyphocrinus there are no syzygies,
although it is possible that in the primitive form of these crinoids, in the inter-
mediate stage without interbrachial structures and with free arms beginning

-

ie)

36 SMITHSONIAN INSTITUTION

with the secundibrachs, the first four brachials were syzygial pairs. Or it
may be considered that the first two pairs of secundibrachs were simply repeti-
tions of the primibrachs, with the second plate of each pair an axillary, analo-
gous to what is seen in the divisional series of Recent crinoids, as pointed out
by Mr. Austin H. Clark in his luminous paper on the Homologies of the Arm-
joints and Arm-divisions in the Recent Crinoids.’

The tegmen.—This is not shown in any of our specimens, but it is cer-
tainly composed of numerous undifferentiated plates with the anal opening
directly through it; and is doubtless substantially the same as that of Glypto-
crinus, as shown by figure 5) of Plate III. It must extend quite high along the
rays, doubtless to the quartibrachs, and these upper extensions may be composed
almost entirely of the consolidated pinnules. Several specimens show where
the interbrachial pavement begins to curve rapidly to the tegmen, and at this
level the pavement is composed exclusively of fixed pinnules (PI. IV, fig. 1).
Messrs. Waagen and Jahn say that the tegmen (votite) is unknown in the
genus, but they direct attention to certain voiites isolees, figured’on their plates
49 and 64, of which they have not been able to find the calyx corresponding.
I have no doubt that these belong to some of their varieties of the genus, and
they clearly show the tegmen to be of the structure above indicated.

The stem.—The full length of the stem is not certainly known, but it was
at least 3 feet (go cm.). Among the Bohemian specimens described by
Waagen and Jahn it was rare to find any part of the stem attached, but Pro-
fessor Jahn in a letter to Mr. Schuchert quoted by him (op. cit., p. 259)
states that he has “observed at Kuchelbad on the exposed surfaces of the
strata Loboliths connected by long columns to Scyphocrinus calices.”’ Schu-
chert (op. cit., p. 262) records having seen at the same locality near Kuchelbad,
Bohemia, a poorly preserved theca of Scyphocrinus with a “long column
probably not less than 3 feet in length, extending toward and terminating
upon a Camarocrinus.”’ This evidence seemed to him at the time so convinc-
ing as to remove all doubt of “ Scyphocrinus and Camarocrinus belonging to
one species.” But a further study of the stem characters led him to revise
this opinion as follows: “ The writer observed that the long column of Scypho-
crinus lying across the Camarocrinus was at least twice as thick as any column
of the latter he had seen. Since then he has determined that the central canal
in the column of Camarocrinus is different in shape and very much smaller in
size than in the associated Scyphocrinus columns.” These differences he
illustrated by text-figure 42, showing transverse sections through the stalk of
Scyphocrinus elegans near the theca, and a thick stalk of Camarocrinus ulrichi
near the roots; the latter is about half the diameter of the former, and has a
small, sharply stellate, axial canal, contrasted with a large quinquelobate canal

*Proc. U. S. National Museum, vol. 35, pp. 113-131, 1908.

CRINOID GENUS SCYPHOCRINUS 37

in the former. And from these facts he concluded finally: “It therefore does
not appear that the two parts can belong to one animal.”

The material now at hand, while not furnishing any complete stem, gives
a thorough exposition of its characters, and enables me to remove the doubts
as to the identity of the two organisms caused by Schuchert’s observations
above cited.

As a matter of fact, the stem of Scyphocrinus—at least of the present
species—tapers gradually from the calyx until its diameter is reduced to
about one-half at the distal end; and it has, moreover, a form of axial canal
which is perfectly consistent with the differences in this respect observed
by Mr. Schuchert. The largest stems are about Io (occasionally 12) mm. in
diameter next to the calyx. The longest portion that can be traced directly from
a calyx and measured is 16 inches (40 cm.), and at this distance it has diminished
in diameter to 8 mm. Beyond this the dimensions cannot be traced continu-
ously, but there are many equally long detached parts of stems belonging
farther down in which the same taper is observed. Concurrently with this
decrease in diameter there is a similarly gradual increase in length of the stem
ossicles, or columnals. Proximal to the calyx where the stem is Io mm. thick
the columnals are very short—several specimens showing an average of
0.7 mm.; and at the distance of 40 cm., with diameter reduced to 8 mm., they
have lengthened to about 1.1 mm. A detached portion of stem about 45 cm.
long changes from 8 mm. in diameter with columnals 1 mm. long at the larger
end to 7 mm. diameter with columnals 1.2 mm. long at the smaller; this
indicates an intermediate position in the stem, where the taper is less than
above. Another of about the same length tapers from 7.5 mm. in diameter
with columnals 1 mm. long to 6.5 mm. diameter with columnals 1.6 mm.
long—representing a more distal section. Shorter portions of stems are found
with still less diameter, in some of which the columnals have increased to 2 mm.
in length for a diameter of 6 mm. If this were near the distal end of an
average mature specimen—as is possible for reasons appearing later—it would
indicate a length of about 3 feet, estimating from the decrease in diameter,
and somewhat more if calculated by the increase in length of columnals. Judg-
ing, however, from the appearance of the longest stem seen in this material,
which is attached to a very large calyx but not in condition for accurate
measurement, the total length in mature specimens must have been consider-
ably more than this.

Together with these external characters must be considered that of the
axial canal; it is very large, obtusely pentagonal in the upper part of the stem,
often appearing to occupy two-thirds of its diameter; and it diminishes more
or less (not always regularly) to a sharply stellate opening distally. This canal
may be described as composed of a series of circular, bi-concave chambers, or

38 SMITHSONIAN INSTITUTION

lenses, separated by a thin partition, or diaphragm, which is pierced by the
pentapetalous or stellate canal. To form these lenses each columnal is usually
excavated on both faces (the ligament fossz), leaving an outer band of the
joint-face flat (the contact area), across which the radiating crenule pass into
the depression toward the center; the apposed concave portions of the joint-
faces enclose the round lenticular chambers, resembling successive enlarge-
ments of the canal, which retains its smaller, pentagonal, or stellate form only
within the thin partition in the middle portion of the columnals (PI. V, figs.
2-5). Inthe upper part, where the columnals are extremely short, these cham-
bers are very wide, leaving only a narrow peripheral band of the full thickness,
and the canal through the partitions is also large; the partitions are very thin
in these parts, so that when the side of the stem is broken away for a consider-
able distance it looks as if there were a continuous canal filled with matrix,
almost the width of the stem (PI. V, figs. 2a, b, c). It is not improbable that
in these portions the partitions were so thin (perhaps membranous) that their
central diaphragms were destroyed during fossilization, or are indistinguish-
able from the matrix. Toward the distal end the concave excavated part
becomes gradually smaller, or may disappear, and the canal through the parti-
tions is more sharply stellate (PI. V, figs. ga, b, 5). In some intermediate por-
tions the chambers are sometimes as narrow as they appear at the distal part;
and in some cases also the chambers appear relatively large in fragments
apparently distal. There is doubtless some variation in this respect, and in
some parts of the stems the chambers are absent in a number of consecutive
columnals; but the general rule is undoubtedly as above stated. These struc-
tures are fully shown by the series of figures on Plate V, above cited, made
from specimens ground, or naturally eroded, which will explain the facts
better than any description. Now it is evident that when the canal and its
enlargements have by infiltration been replaced by firm matrix, if a cross
fracture in the upper part occurs along the joint-face, the resulting section will
show the canal large and round; if through the middle of the columnal, the
canal will appear smaller, pentagonal, or stellate. Similar cross-sections toward
the distal part will show a round or sharply stellate canal, according to the
position of the fracture, the latter predominating. This will account for the
different varieties of stem sections and isolated stem joints seen in various
parts of the material.

There is a frequent tendency in stems with a large axial opening and
branching or expanding root to become more and more modified toward the
distal end; and also for the columnals, after having increased in length for
most of the distance, to become shorter again at the end. This may be seen in
stems of Barycrinus, Anomalocrinus, and other forms.

CRINOID GENUS SCYPHOCRINUS 39

The bi-convex chambers in this stem are similar to those in the proximal
part of the stem of Apiocrinus (see de Loriol, Pal. Frangaise, Crinoids, vol. 1,
pl. 34, fig. 3).

Among the numerous restes indeterminés figured by Waagen and Jahn
the various stem characters above described are shown in profusion.

The terminal bulbs (Camarocrinus) are large, but all much flattened;
some of them in this condition are 13 cm. in diameter. Since for the reasons
already explained the side exposed upon the slabs is the lower or non-stalked
side as it rested in the sea bottom, and the stalked side is invariably buried in
a mass of stems, arms, and pinnules, compressed into a limestone matrix, we
do not in any case see the actual stem attachment. Some indications of the
branching roots appear in a few places, but nowhere sufficiently well preserved
for intelligent study. The bulbs are seen to be divided into compartments as
usual, and were probably generally similar to those found elsewhere. But
comparing specimens of Camarocrinus from other localities in which the stem
attachment is well preserved, and which are associated in occurrence with the
calices of Scyphocrinus in large numbers, it is now very interesting to note that
the size of the stem and form of the axial canal at the distal end are precisely
what we should expect to find in connection with the stem above described.
In upwards of 75 specimens of Camarocrinus bulbs from Tennessee, ranging
from minimum to maximum size, all preserving the stem attachment, I find that
the stem at the distal end varies from 2 mm. diameter in the smallest to 9 mm.
in the largest—in those of medium size being about 5 to 6 mm.; and in none
of those of maximum size does the stem equal in diameter that of the proximal
columnals in specimens of S. prattent found in the same beds. In the S. pyburn-
ensis locality the stem attachment of the largest Camarocrinus does not exceed
5 mm. in diameter, while that of average sized calices of that species is 9 mm.
In all cases the canal is stellate and relatively small, like that of figure 6 of
Plate V.

Types.—The specimen described by Zenker is in the University of Leipzig,
and those by Waagen and Jahn are in the Bohemian Museum at Prague. The
American specimens here figured are in the author’s collection in the U. S.
National Museum.

Horizon and locality—In America, Helderbergian; Bailey limestone,
perhaps equivalent to the New Scotland formation. A single imperfect speci-
men among the collections from Hardin County, Tennessee, may belong to
this species. Otherwise its occurrence is limited to the Cape Girardeau, Mis-
souri, region—although it is likely to be found in the same beds farther east-
ward, in Illinois, where the stems have been seen.

40 SMITHSONIAN INSTITUTION

FURTHER REMARKS UPON THE FIXED PINNULES

The study of the fixed pinnules in Scyphocrinus, as described in the fore-
going pages, led me to review the facts bearing upon analogous structures in
other genera, with some curious results:

In 1878 Wachsmuth and Springer* called attention for the first time to
certain openings in the test of crinoids located near the base of the arms
“pierced through at the edge of the plate and enclosed by the abutting margin
of an adjoining plate.’’ Those then described were observed in Eucladocrinus,
and it was stated that they are also found in Batocrinus, Actinocrinus, etc.,
and “ within the false arms of Ollacrinus” (Gilbertsocrinus). It was suggested
that they might have respiratory functions.

In the Revision of the Palaeocrinoidea, Part I (1879), p. 11, and
Part II (1881), pp. 51-53, we discussed these openings at length, giving to
them at the latter place for convenience the term “ respiratory pores.” After
stating the possibility of their being respiratory or ovarian openings, we
observed (p. 52): ‘‘ There are objections to this, and another interpretation
is at least possible. From what we now know of the ontogeny of the Palaeozoic
crinoids, we are inclined to think that the pores may have been originally
pinnules, which with progressing growth were soldered into the body.” We
suggested the desirability of tracing the pores in genera like Glyptocrinus,
“in which the fixed pinnules retained their forms after they became fixed ”’;
and we also referred to a possible analogy with the proximal pinnules in the
Recent crinoids (p. 53).

In North American Crinoidea Camerata (1897), p. 35, we stated that
the disk in many Camerata has “small respiratory pores or slits near the
arm-bases, piercing the sides of the plates’’; and on p. 122 we explained that
“the openings are always located between the rays and their main divisions,
a little above the arm regions,” and that “in Dolatocrinus they are slit-like, in
Batocrinus round, and in Gilbertsocrinus at the end of a long tube.”’

Bather, in Lankester’s Zoology (1900), Part III, Echinodermata, p. 130,
confirms the observations of Wachsmuth and Springer, giving one of our
figures and one of his own (fig. 45) which show the form and position of the
slits and pores in Dolatocrinus and Batocrinus; and he says that the supposition
“as to the existence in Camerata of a complicated water-vascular system, is
supported by the connection of the internal passages with small pores near
the arm-bases,” and that “the pores may possibly have replaced the hydropore
or the madreporite of certain Inadunata.”

Specimens acquired since the dates of the above-cited publications have
thrown new light upon the nature of these structures, and enable us, I think,

* Proc. Acad. Nat. Sci., Philadelphia, vol. 30, p. 248.

CRINOID GENUS SCYPHOCRINUS 4I

to definitely settle their relations. The descriptions of the openings given by
Wachsmuth and Springer, already mentioned, are quite complete for the genera
in which they had then been observed. The important points to remember
are: that these openings are situated at the margin of the tegmen, in the
brachial zone, where the dorsal and ventral walls meet; that they do not
penetrate the plates, but lie at their angles or within the sutures; and that they
stand in close relation to the arm-openings. Thus they have not the structure
of madrepores. Taking Batocrinus as a normal example, it will be seen that
the pores are small, enter the calyx wall obliquely at the side of the arm-
openings by passages which connect directly with the food canals; in other
words, the passages leading to the pores are branches of the food canals (see
Reva bal: vol 2; pl, 10, fig. 45 and) N., AceCrin. Cam», \pl:y274) neavea) alo
better show the exact relation of the grooves leading from these openings to
the food canals I give an enlarged transverse view of the calyx wall in
Batocrinus at the level of the arm-openings (text-fig. 17); thus they branch
from the food groove leading to the arms exactly as pinnule grooves would.

In Dolatocrinus the openings take the form of narrow slits, running ven-
tralwards from the dorsoventral margin where the main point of exit was
located (N. A. Crin. Cam., pl. 25, figs. 6b, c, d; pl. 26, figs. Ia, 5b, 6a): here
the number of openings is greatly increased, amounting to six or eight in
D. grandis M. and G. (Bull. 4, Ill. St. Mus. Nat. Hist., pl. 2, figs. 2, 3). The
appearance of the pores in Eucladocrinus and Cactocrinus respectively is shown
invNe AY Crin! Cam), pl) 84; fie. '5;pl. 57; fs. 10; (pl. 58; hey 6:

Coming now to the new material, a very instructive case is found in the
genus Cyphocrinus S. A. Miller (Hyptiocrinus W. and Sp.), one of the few
crinoids in which the biserial arm structure extends down into the calyx wall—
a fact which is seen only in very well-preserved specimens (text-fig. 18). The
cuneiform secundibrachs give rise to a series of plates from each longer face
which lead to elongate pores in the brachial zone, two pinnule ossicles being
incorporated in the dorsal wall; and further incorporation of pinnules upon
the tertibrachs occurs, producing as many as six pores to the interradius. The
course of these series is similar to that of the fixed pinnules in Glyptocrinus
as they would be in the early stages.

The decisive evidence, however, is found in the Silurian genus Marsipo-
crinus. On account of the silicified condition in which the specimens are
usually found in the American localities, the presence of the interbrachial
pores has not hitherto been noted; but some extremely fine specimens obtained
in recent years from Tennessee not only show their existence in this genus, but
demonstrate beyond the slightest doubt that these openings are in the sockets
of pinnules originating below the bases of the free arms. The openings them-
selves are small, usually obscure, and there is nothing on the dorsal side to

42 SMITHSONIAN INSTITUTION

indicate their position; but the branching ambulacra in the tegmen show it
perfectly. These, corresponding in position to brachials either actual or poten-
tial on the dorsal side, have a main series of covering plates leading to the
arm-openings, and from the sides of this smaller series branch off and lead
to two or more pores at either side of the arm-bases. The branching ambulacra
are well shown in Wachsmuth and Springer’s figure of the tegmen of Marsipo-
crinus radiatus (see N. A. Crin. Cam., pl. 8, fig. 15), reproduced by Bather in
Lankester’s Zoology (p. 124, fig. 32). The exact relation of the smaller
branches to the plates, and to the pores themselves, is better shown in text-
figure 19, diagrammatized from one of the Tennessee specimens figured on
Plate IX, figure 6. The first lateral branches and their pores are seen to belong
to the secundibrachs, with one large pinnule ossicle incorporated, and are
followed by those from the interlocking brachials of the arm. Ali that is
needed further is to show the pinnules themselves which we now have per-

Fics. 17-19
Fig. 17, Batocrinus clypeatus. Transverse section at arm-openings, plates separated
at sutures; the passages from the so-called “respiratory pores” connecting with the food
canals. X<§. 18, Cyphocrinus gorbyi. An interradius with adjacent arm-bases showing
pores in plates corresponding in position to pinnule ossicles. 4. 19, Marsipocrinus
striatus(?). Diagram of one ray of specimen figured on PI. IX, fig. 6, showing position
of pinnule openings and ambulacra leading to them. 3.

fectly preserved, both brachial and interbrachial, in the beautiful specimen of
M. tennesseensis figured on Plate IX, figures 5a, b.

An excellent example of secundibrach pinnules is seen in Platycrinus
huntsville, where they are often very conspicuous, and stand out distinctly
larger than those upon the arms (they are well shown in N. A. Crin. Cam.,
pl. 73, figs. 7b and g). In this species, as well as in the Marsipocrinus, it is
the first secundibrach which bears the pinnule, these being forms in which the
primibrach series is reduced to a single plate—the axillary.

In the foregoing text-figures 17-19 are shown various stages of develop-
ment in the incorporation of pinnules, and also the different methods by which
their ambulacra empty into the main ambulacra:

The first stage is that in which an arm ossicle is incorporated in the
dorsal cup without incorporation of its pinnule (Batocrinus, fig. 17). In this

CRINOID GENUS SCYPHOCRINUS © 43

stage the ossicle still shows its axillary character, and the ambulacrum of the
pinnule empties into the main ambulacrum within the ossicle.

In the second stage incorporation of the pinnulate arm ossicles is accom-
panied by incorporation of one (Marsipocrinus, fig. 19) or more (Cyphocrinus,
fig. 18) pinnule ossicles. Various changes are here necessitated in the position
of pinnule ambulacra in reference to their respective arm ossicles, as the upward
shifting of the mouth has caused a separation of the ambulacra from the plates
with which they were formerly in contact. Thus in Marsipocrinus and Cypho-
crinus the ambulacra on the incorporated pinnules of the first and second III Br
pass directly into the main ambulacra (note position of ambulacral covering
plates in Marsipocrinus), without grooving the arm ossicles from which the
pinnules are given off.

The third stage is that illustrated in Glyptocrinus and Scyphocrinus, in
which the lowest pinnules are almost completely incorporated in the cup.

In the first and second stages the openings of the pinnule ambulacra into
the cup are clearly defined; in the third stage, however, the opening is lost, as
the ambulacra have probably atrophied, or the pinnules become so merged in
the finely plated perisome passing into the tegmen that their openings cannot
be discovered.

From all these facts it is clearly evident that the openings in question in
Camerate crinoids represent the pinnules which developed immediately follow-
ing the first division of the ray in the young crinoid, and became afterwards
more or less incorporated by the growth of the calyx. They are comparable
to the proximal pinnules in the Comatulids, which differ in many notable
respects from those which succeed them. Mr. Austin H. Clark, to whom I
applied for detailed information, has been kind enough to furnish me a note
embodying numerous examples of this fact, which with his permission I am
here inserting:

Among the Comatulids the pinnules of the first pair, usually also those of the second,
frequently those of the third, and sometimes those of the fourth and fifth, are different
in structure and function from those succeeding. They are invariably sterile and without
ambulacral groove or tentacular apparatus, and are so modified that, instead of serving
as food collectors like the distal pinnules, or as sexual organs and usually also as food
collectors like the middle (genital) pinnules, they function as highly sensitive tactile
organs, or as spine-like organs of defense.

In certain genera, distributed in widely different groups (for example, in Antedon,
Florometra, Pontimetra, and Pentametrocrinus), the oral pinnules, composed of numerous
very short segments, are greatly elongated and of extraordinary flexibility, calling to mind
the antennz of certain crustaceans. In these genera they appear to serve simply as tactile
organs.

In one family (Comasteride) the outer segments of these tactile pinnules bear long
triangular processes which collectively form a prominent comb-like structure: the function
of this is not clearly understood; it may serve as a cleaning apparatus, or merely to
increase the intricacy and sensitiveness of the entanglement over the disk.

7

ANN SMITHSONIAN INSTITUTION

In a few species (mostly in the genera Stephanometra, Colobometra, and Oxymetra)
the pinnules of the first two or three pairs are stout, extremely stiff and spine-like, sharp
pointed, composed of very few elongated segments, and project diagonally outward over
the disk which is thus protected by a mass of sharp thorns.’

Usually, however, the protective function is confined to the pinnules of the second
and one or two following pairs, the pinnules of the first pair remaining many-jointed,
delicate and flagellate, tactile organs.

In most of the genera of the Thlassometride (as in Thalassometra) and in certain
species of Himerometra, the pinnules of the first pair are very stout for most of their
length, but end in a delicate flagellate tip, thus combining both tactile and protective func-
tions in the same organ.

In the Comatulids whenever the division series consist of four segments, the second
always bears a pinnule; whenever they consist of three segments (the palmar and sub-
sequent division series in Capillaster and Nemaster), the first bears a pinnule. The
pinnules borne on the division series always are of the same character as the first pinnule
of the undivided arm, but with its distinctive features accentuated; thus if the first arm
pinnule is larger and stouter than the second, the palmar pinnules will be in turn slightly
larger and stouter than the first pinnule, and the distichal pinnules slightly larger and
stouter than the palmar; if the first arm pinnule is smaller and weaker than the second,
the palmar pinnules will be still smaller and weaker, and the distichal pinnules smaller
and weaker than the palmar.

As the surface of the disk ordinarily reaches the level of the second brachial, it
naturally follows that before becoming free the pinnules of the division series must run
along over the dorsal perisome for some distance; but owing to the deep interradial
incision of the disk in most multibrachiate forms this means little more than that these
pinnules run diagonally upward to and beyond the edge of a much thickened brachial
perisome.

In a few multibrachiate types (as in Comaster belli and Comanthina schlegelii) the
disk is approximately circular, with the bases of the distichal and palmar pinnules incor-
porated in the dorsal perisome. This dorsal perisome may become heavily plated, in which
event the pinnule bases become invariably fixed in a pavement of very irregular polygonal
plates from which, however, the pinnulars are always readily distinguishable because of
their height, strong convexity, and regularity in size and shape; in other words, in recent
types the fundamental character of the pinnule as a free organ is never in the slightest
degree masked by incorporation in the perisomic wall.

It will be observed that the condition described in the last paragraph of
Mr. Clark’s note is substantially the same as that of the fixed pinnules in the
various fossil genera mentioned above, except for the greater tendency of the
pinnules in fossil forms to merge in the perisome.

From the various examples thus given of the form and function of the
proximal pinnules, it is seen that these organs frequently undergo a course of
development wholly different from those succeeding them at regular intervals
along the arms; and it is to this tendency to unequal growth that we must
look for an explanation of the extraordinary condition found in Gilbertsocrinus.
Most authors who have mentioned them have treated the tubular extensions
in this genus as analogous to the interbrachial pores in Batocrinus and other

*See Hartlaub (Comatuliden des Indischen Archipels), Nova Acta Ksl. Leop.-Carol. Deutsch.
Akad. Naturforscher, Band 58, Taf. 3, fig. 29, 1891.

CRINOID GENUS SCYPHOCRINUS 45

genera, and as performing the same function; but it is certainly a long road
from a pinnule, usually regarded as a miniature arm, to such ponderous struc-
tures as the interradially located tubes of a form like Gilbertsocrinus typus
(N. A. Crin. Cam., pl. 14, fig. 1), built up of circular segments like a stem.
Nevertheless, their common origin is clear.

In their earliest stages (Devonian and the base of the Lower Carbon-
iferous) the tubes were short (G. spinigerus, G. stellaris, and G. fiscellus (N. A.
Crin. Cam., pl. 15, figs. 3b, e, and 4; pl. 17, fig. 2a). In G. stellaris (deKoninck
and Lehon) we have a Rhodocrinus with the pores next to the arm-bases
extended into small tubes, of probably very few segments, without any ventral
groove; they are at the interradial sides of the ray. In other European species
of Lower Carboniferous age—for example, G. calcaratus Phill. (N. A. Crin.
Cam., pl. 15, fig. 5)—the tubes have become large, but are still separate and
radially located. In the upper Burlington limestone (N. A. Crin. Cam., pl. 14,
fig. 1) the tubes attained a size which dwarfs all the other parts of the crinoid,
being more than twice as long as the extreme length of the calyx, and as thick
as the stem. Those from adjacent rays unite above the interradius, coalesce
by zigzag sutures for a distance of six or eight plates, beyond which they
separate and taper gradually to a point. Thus while of radial origin, the
tube where doubled is interradial in position. Each tube is perforated through-
out by a central canal, and not only is it composed of circular undivided seg-
ments like the ossicles of a column, but the joint-faces are often somewhat
striated like those of stems—there being no semblance of the articulation
belonging to arms or pinnules, nor of any ventral groove. The construction,
therefore, is that of a stem appendage rather than of an arm appendage.

In the Keokuk limestone another curious change occurs (N. A. Crin.
Cam., pl. 16, figs. 1-6). The tubes from adjacent rays coalesce interradially as
before for a short distance and then separate; but instead of being com-
posed of undivided segments like a stem, they take on the construction of an
arm or pinnule, so that there is one plate (brachial) dorsally and two large
plates at the ventral side which interlock like covering plates. Of course,
where the tubes are joined the number of these elements appears doubled. The
tubes are longitudinally perforated by a fair-sized channel, but there is no
ventral groove. This change marks the end of the genus; and this type of
extreme aberrant growth of pore or pinnule is seen no more among the crinoids.

It is evident that this extraordinary development from a pinnule having
a tendency to irregular growth must be interpreted as a pure case of hyper-
trophy in which the original character of the organ was wholly lost, followed
by an effort at recovery in the expiring struggles of the genus. And it is now
most interesting that a condition comparable to this, and which gives a clue
to the strange tendencies which might give direction to the impulse of hyper-

46 SMITHSONIAN INSTITUTION

trophy toward such a singular result, is to be found among the Recent crinoids.
In Comatulella brachiolata (Lamarck), the delicate, regular pinnules alternate
with others which are much stouter, without any ventral grooves and wholly
unconnected with the ambulacral groove of the arm; they are composed of
circular segments which are solid except for a minute central perforation.
Mr. Austin H. Clark has figured a specimen of this rare species in Ergebnisse
der Hamburger sudwest-australischen Forschungsreise (Supplement, 1913,
pl. 4, figs. 1, 2); and in the Records of the Western Australian Museum
(vol. I, 1915, p. 117) he has given a full description based upon another fine
specimen not yet figured. Speaking of the ungrooved pinnules he says (p. 118):

At first they lie horizontally, but in the distal half or third they curve dorsally into
the form of a hook or spiral, exactly as do the cirri, forming tendril-like attachments all
along the arm whereby the animal fixes each arm securely to the organisms on the sea
floor in addition to fixing its central portion by means of its cirri. [And he adds on p. 119]
It is most instructive to see that in this specimen the ungrooved pinnules have approached
so closely to the cirri in structure that they have taken upon themselves the performance
of exactly the same functions.

In like manner the tubes of such a form as Gilbertsocrinus typus, while
occupying the position of proximal pinnules, may be considered as representing
enormously enlarged cirri.

While, therefore, the suggestion of Wachsmuth and Springer as to the
probable derivation of the so-called “ respiratory pores” from pinnules is con-
firmed, it is also true that these pinnules may have possessed respiratory
functions, since the proximal pinnules in many Recent crinoids are shown to
be lacking the usual functions of pinnules.

2. SCYPHOCRINUS SPINIFER N. Sp.
Plate IX, figs. 1a-c

Calyx narrowly elongate, widest about arm-bases; height to width about
as 4:3. Plates sharply sculptured, with conspicuous ridges traversing the plates
continuously from center to center, diminishing in number from five at the base
to one at the first axillary; these meet at the centers of the plates in small
elevations surmounted by long spines which frequently fork. Radial series
slightly elevated; median ridge of secundibrachs sharp and narrow. Secundi-
brachs 12 or 13.

Height of the only specimen, 40 mm.; width about level of arm-bases,
30 mm. Length of spines, 5 to 7 mm.; thickness at base, about I mm.

The remarkable character of this species is the spines which are entirely
different from the small pustulose elevations seen on specimens of S. pratteni;
they are relatively long, and slender at the base, many of them enlarging
distally and often forking, while others taper to a point. They occur on the
radial series to about the fourth secundibrach, and upon the interbrachials

CRINOID GENUS SCYPHOCRINUS 47

(and possibly pinnulars and interpinnulars) to the height of the arm-bases;
thus the interbrachial spaces appear thickly studded with the spines, which
diminish in size upward. There is a certain uniformity of direction in which
numbers of adjacent spines lie in clusters which leads to the conclusion that
they were articulated; this is confirmed by the appearance of the small, elevated
centers of the plates, which look like sockets, and by the proportions of the
spines themselves. The usual fixed spines, developed from pustulose growths
upon the plates, are broadest at the base, from which they taper conically;
whereas these are narrow at the base, cylindrical for the greater part of their
length, after which many of them expand or branch.

The species is represented by a single specimen in a remarkably good con-
dition, all the structures being sharply preserved. In the part originally
exposed only a few of the smaller spines were visible in the upper inter-
brachial region (PI. IX, fig. ta). But careful cleaning from the rather hard
matrix brought to view not only the fringe of long spines lying parallel in
clusters at either border of the same side, but also a good part of the opposite
side of the specimen, on which a forest of spines lie in place to the level of the
upper secundibrachs (Pl. IX, fig. 1b). On this side also the sharp sculpturing
of the lower calyx plates is beautifully shown.

The presence of articulated spines in this isolated species of so prolific a
genus is a most remarkable occurrence, suggesting comparison with the other
Devonian form, Arthracantha, in which the character seems to be constant for
all the species. The branching or distal enlargement in our species is, however,
a development for which no parallel is thus far known among the crinoids. In
view of the fragile nature of these structures, and the impediments to their
preservation in the fossils, it is quite possible that some of the other species may
have possessed similar spines; for example, S. stellatus, and the species repre-
sented by the fragments from Benton County, Tennessee (figured on Pl. VI),
in which the sculpturing is very similar.

Type.—The holotype is in the author’s collection.
Horizon and locality.—Helderbergian; Ross limestone of the Linden for-
mation, Hardin County, Tennessee.

3. ScyPHOCRINUS MUTABILIS n. sp.
Plates VI, figs. 3-19; VIII, figs. 3, 4, 5

A variable species of the elegans group, with strong surface sculpture.
Calyx of medium size, usually wider than high, but sometimes slightly elongate ;
lower part of cup broadly expanding, with sides usually convex, rarely about
straight, or slightly concave near the base. Secundibrachs 12 to 15, the upper
seven or eight very short and wide; median ridge varying from medium size

48 SMITHSONIAN INSTITUTION

to rather broad, in some cases appearing to ramify downward. Interbrachials
not protuberant. Plates low-convex, with crenulate margins, and radiating
ridges changing from fine to coarse upward, but with pits at the corners almost
everywhere sharp and specially conspicuous; those of the interbrachial pave-
ment often greatly modified by the sculpturing into strong bands, irregular
network, and stellate figures, in which the fixed pinnules can rarely be traced.

Dimensions of specimens as usually found: Height to axillary IIBr,
40 to 60 mm.; width at upper level, about the same; an average well-preserved,
rotund specimen, slightly elongate in appearance, is 60 by 55 mm.

I have proposed this species to receive a rather variable form which is
found in the Linden formation at several localities in Benton, Perry, and
Hardin counties, Tennessee. Only in the latter region have I been able to
obtain good specimens, but it must have been an abundant and well-distin-
guished species, to judge from the many fragments that have been seen in the
other regions mentioned. It is distinguished from S$. elegans by the less
elongate form and fewer secundibrachs, and of course from its associated
species of the pratteni type by the general form. S. stellatus, if we knew it
from better specimens, might be found to include these forms. The pits at the
corners of the plates seem to be the most constantly conspicuous feature in the
sculpturing. In some specimens little else is seen; in some the surface is dotted
more or less thickly with small knobs apparently formed by inorganic silicious
deposit. Chemical action has often greatly altered the superficial appearance,
producing a semblance of sculpture quite different from the normal. In some
cases the knobs lie chiefly upon the suture lines, exaggerating the connecting
ridges to such an extent that the plates appear to be surrounded by them.
In some the striz and crenulate margins are feebly shown; while in others they
are strong and sharp, coalescing upward as usual. Erosion has sometimes
made the plates appear smooth and almost flat, especially in the lower parts. In
some specimens the ridge of secundibrachs is very wide, and in others rather
narrow; in some the basal part of the calyx is rather narrowly conical, and in
others somewhat obtusely and irregularly curved; rarely small median spines
are seen. Upon some of these differences my inclination was at first to pro-
pose other species, but there is nothing constant about them. In the inter-
brachial pavement most of the types common to S. elegans are found among
these forms.

The species is rather widely distributed; in Hardin County, where the
best specimens were obtained, it is found chiefly in limestone layérs at both the
Pyburn and Horse Creek localities, more or less irregularly throughout the
pyburnensis and prattent beds. Occasional imperfect calices occur in Perry
County in the Decatur and Linden horizons, while in Benton County it is
numerously represented by weathered fragments from the large colony already

CRINOID GENUS SCYPHOCRINUS 49

mentioned filled with the remains of calices and bulbous roots, all broken into
small pieces. Many of these have the surface structures, both external and
internal, beautifully preserved, and I have figured several of them on Plate VI,
for various details. They show, among other things, pits resembling folds upon
the sutural edges of the plates in a dorsoventral direction, already described;
and also radiating striz upon the inner surface of the plates.

Types.—Author’s collection. The specimens figured on Plate VIII are con-
sidered the types rather than those on Plate VI, the figures of which were
drawn from imperfect specimens and printed before the later material was
obtained.

Horizon and locality.—Niagaran to Helderbergian, from the Decatur lime-
stone throughout the Linden formation; Hardin, Perry, and Benton counties,
Tennessee.

4. SCYPHOCRINUS STELLATUS (Hall)
Plate VII, figs. 4a, b

1879. Camarocrinus stellatus Hall; 28th Rep. N. Y. St. Mus. Nat. Hist., 270, pl. 35,
figs. 1-8.

1904. Rice elad. stellatus Hall; Schuchert, Smithson. Misc. Coll., vol. 47, pt. 2, pp. 269,
270, pl. 44, figs. 1-5.

1913. Camarocrinus stellatus Hall; Schuchert, Maryland Geol. Surv., Lower Devonian, 228,
pl. 31, figs. 1-5.

Calyx short, obconical, spreading gradually to the arm-bases; height about
equal to maximum width. Plates low, rugose, with indistinct radiating mark-
ings below, and strong connecting ridges and deep pits above, producing a low,
stellate sculpture. Secundibrachs about 10, the upper ones about half as long
as wide, being relatively longer than in many other species. Median ridge
narrow. Arms and stem unknown.

The form of Camarocrinus occurring numerously at Schoharie, New York,
and in the beds at Keyser, West Virginia, mentioned by Hall and Schuchert,
was described by the former under the above specific name. A single imperfect
calyx has been found in the Keyser locality, upon which I have undertaken
to characterize the species. Some of the fragments from Benton County,
Tennessee, may belong to this species. While the bulbs from the Keyser locality
contain numerous examples of the primitive four lobes, and variations from
that number to eleven, it must be said that taken as a whole they show a much
greater tendency to increase in number of lobes than those from Oklahoma
and Tennessee. Therefore, while a single bulb would prove nothing, the preva-
lence of the higher numbers in a considerable assemblage of specimens may
be taken as a specific character. Also on an average those of this locality are
relatively lower and broader than the others, and in general considerably
smaller.

50 SMITHSONIAN INSTITUTION

Holotype.—The calyx herein described is in the author’s collection.

Horizon and locality —Keyser division of Helderbergian, Schoharie, New
York; Keyser, West Virginia. Possibly also the Linden formation in Benton
County, Tennessee.

5. SCYPHOCRINUS PRATTENI (McChesney)
Plates VII, figs. 1a, b; VIII, figs. 1, 2a, b
1860. Forbesiocrinus pratteni McChesney ; Trans. Chicago Acad. Sci., Extract No. 1, p. 29.
1865. Forbesiocrinus pratteni McChesney; plates illustrating in part new species fossils,

ple Ssifige 4:
1866. Melocrinus pratteni (McChesney); Shumard, Trans. Acad. Sci. St. Louis, vol. 2.

p. 381.
1868. Melocrinus pratteni (McChesney) ; McChesney, Trans. Chicago Acad. Sci., vol. 1,

p. 22, pl. 5, fig. 4.
1881. Melocrinus prattent (McChesney) ; Wach. and Spr., Proc. Acad. N. S. Phil., 296

(Rev. Pal., vol. 2, p. 122).
(?) Syn. Camarocrinus saffordi Hall, 1879, 28th Rep. N. Y. St. Cab.

Nat. Hist., 208; pl. 36, figs. 1-6; pl. 37, figs. 1, 2; Schuchert, 1904, Smith-
son. Misc. Coll., vol. 47, pt. 2, p. 270, pl. 40, fig. Io.

Calyx extremely large, massive, lageniform; broadly conical from base
to widest part about the zone of axillary primibrach, thence contracting and
becoming cylindrical toward the arm-bases. Height about equal to maximum
width. Interbrachial areas at widest part strongly protuberant, with primi-
brachs and first secundibrachs deeply depressed between them; higher up this
condition is reversed, the secundibrachs being elevated into a broad median
ridge, while the interbrachial pavement (fixed pinnules) is low, rather flat,
with obscure sculpturing. Secundibrachs about 12, the first being elongate,
followed by gradual diminution in length until the upper ones are less than
one-eighth as long as wide; median ridge begins at about the fifth plate, passing
into a broadly rounded trunk toward the arms. Fixed pinnules strongly modi-
fied by surface sculpture, and not readily distinguishable. Primary inter-
brachials large, in about five or six ranges of I, 2, 3, 3, 2, I, with one or more
additional plates in the posterior interradius for the ranges above the second.
Plates in lower part thick, convex, smooth, with obscure connecting ridges,
often pustulose or obtusely spiniferous; in the upper interbrachial region flat
and without sculpturing. Arms and stem not preserved, except for a few of
the proximal columnals, which are extremely thin.

Dimensions of a maximum specimen: Height of calyx to axillary secundi-
brach, 90 mm.; width at widest part about 100 mm., reduced above to about
75 mm.; diameter of column proximal to calyx, 12 mm. Diameter of asso-
ciated root bulbs, 150 mm.

This species is the most striking example of the group to which it belongs,
and is so completely distinct in facies from those of the elegans group as not

CRINOID GENUS SCYPHOCRINUS 51

to require detailed comparison. Its most emphatic characters are the flask-
shaped calyx, swollen interbrachial areas, and extremely large size—all of
which are conspicuously shown in the unusually fine material now in my hands
as the result of Mr. Pate’s collecting in 1915. There are about 35 specimens,
from four localities within a limited area in Hardin County, Tennessee, several
of which by dint of hard cleaning have been completely freed from the matrix;
none have the arms preserved, but in several the secundibrach series is intact
in one or more rays up to the bifurcation. The size is remarkably constant at
a height and width of about 75 mm. or more, with a contraction of 20 to 25 mm.
above the strongly bulging interbrachial zone; but a single specimen was found
of materially less size than that stated.

The contour, ventricose in the middle, contracted and cylindrical above,
is similar to that of S. pyburnensis, but it is much more pronounced in this
species. It is chiefly caused by the swollen condition of the interbrachial
areas, projecting in some specimens as much as 10 or 12 mm. beyond the plane
of the primibrachs, which lie deeply and abruptly depressed between them, as
if sunken into the calyx wall.

The number of secundibrachs is a good character as distinguished from
that in S. elegans, being quite constantly about 12 or 13 in the specimens where
they can be counted—the smaller number according with the less elongate calyx.
The interbrachial pavement, being in the weaker part of the calyx, is complete
in but few of the specimens; so far as seen it is rather smooth, with low con-
necting ridges and shallow pits, which so strongly modify the plates that the
fixed pinnules are with difficulty identifiable. In one specimen they are quite
plain on the interior, with traces of ambulacra toward the distal ends.

The short, pustulose elevations in the center of many of the plates, while
generally present, are somewhat variable, and upon a set of five specimens
from a different locality from the others they are wanting; but the form is
otherwise indistinguishable from the prevailing type.

The Camarocrinus bulbs found in the prattent beds are in size commen-
surate with the dimensions of the calyx, far exceeding those of any other
horizon or locality. Many of them are 150 mm. or more in diameter and almost
as high, and none were seen less than about 100 mm., which is the usual
maximum for those of other species. The average diameter in 12 specimens
is 125 mm., while the average of 70 specimens from the clay beds below is
75 mm. It is also observed that the principal root members and their connect-
ing pavement stand at an acute angle toward the stem, forming a pyramidal
or conical mass within the collar, whereas in the other specimens the floor is
usually almost horizontal. Also the sinus between the lobes is usually more
sharply indented than in the others.

8

52 SMITHSONIAN INSTITUTION

While S. pratteni, in its extraordinary size and the anomalous develop-
ment of the interbrachial areas, represents the culmination but evidently not
the close, of the genus, it is interesting to note that there is a progression in
these characters within the species itself. The strata containing it consist of
blue and grey limestones in the lower part, passing into cherty beds above.
It is in the latter that the largest specimens with the greatest and most abrupt
interbrachial projections are found; while those from the lower bluish lime-
stones are in the average smaller and of a distinctly less rugose type.

The species was described from a fragment in which but a small part of
the calyx was preserved, and the leading characters were not disclosed. In
his original description McChesney stated that the horizon and locality of the
unique type specimen were not clearly known, but it was supposed to have
been from the Carboniferous limestone somewhere in Alabama. The horizon
is, of course, wrong; but as the same Linden beds in which the Hardin County
specimens occur extend along the Tennessee River into northwestern Alabama,
there is no doubt that the type specimen was derived from the same source.

Holotype.—Originally in the Chicago Academy of Science, was destroyed
by fire, but is represented by casts in the American Museum of Natural History,
New York; the Walker Museum of the University of Chicago; and in the
author’s collection at the National Museum. The other specimens here figured
are in the author’s collection.

Horizon and locality—Helderbergian; lower or middle part of Ross
limestone of the Linden formation; Hardin County, Tennessee, at various
localities along Horse Creek, near Grandview on the Tennessee River, and
probably also in northwestern Alabama. The species occurs in the upper
25 or 30 feet of a series of blue-grey and cherty limestones with clay partings,
of a total thickness of about 60 feet, in which are also found Camarocrinus
of maximum size. It is not found at Pyburn’s Bluff, where similar beds of
cherty limestone exist, but evidently lack the prattent member, which may at
that locality lie below the water’s edge.

6. ScYPHOCRINUS PYBURNENSIS Nn. sp.
Plates VII, figs. 2a, b, 3; VIII, figs. 6a, b, 7

Calyx large, elongate; low-convex in lower part, widest below secundi-
brachs, contracting and cylindrical toward the arm-bases; height to width at
zone of greatest width and to that above, 2.75 to 2.20 to 2. Interbrachial areas
slightly protuberant, giving an obtusely pentagonal cross-section at that level,
and unsymmetric by reason of greater and rather irregular enlargement of
posterior interradius, which usually has two or three additional plates above

CRINOID GENUS SCYPHOCRINUS 53

the second range. Secundibrachs about 13 to 15, with median ridge rather
narrow, commencing at about the sixth or eighth plate; fixed pinnules fre-
quently distinguishable in regular order. Plates thick, not pustulose; broadly
convex in lower part, with strong stellate sculpture above, produced by rather
broad connecting ridges and pits. Arms apparently rather slender.

Dimensions of a large specimen: Height of calyx, 70 mm.; width at widest
interbrachial zone 57 mm., reduced directly above to 50 mm., beyond which it
expands again to the arm-bases; diameter of stem at calyx, 9 mm.

This is a thoroughly well-marked and abundant species, of the type of
S. prattent, but differing consistently, and from a different horizon. At
Pyburn’s Bluff, on the Tennessee River, which is its typical locality, pratten:
does not occur at all, while at the four localities where that species is the
principal crinoid, pyburnensis was not found except for a single specimen in
the talus, clearly derived from higher beds. The material in hand consists of
35 specimens, many of which have one or more rays intact to the bifurcation
above the secundibrachs. In one an arm is preserved for two branchings,
much more slender than those of S. elegans. All the specimens are readily
distinguished from S. pratteni by the more elongate calyx, less prominent
protuberance of the interbrachial areas, greater asymmetry of the posterior
interradius, and lack of the spinose center on the plates. In very elongate
specimens, such as that of Plate VI, figures 2a, b, the secundibrachs retain the
elongate form and general aspect of calyx plates to the height of seven or
eight plates before passing into the median ridge; above that they become
very short and wide. There is not much variation in size, specimens being
rarely less than 50 mm. high, unless the few which I have mentioned under
S. gibbosus should prove to be the young of this species.

The fixed pinnules are better defined in this than in any of the other
Tennessee species. I have figured two specimens in which their course is
perfectly plain (Pl. VII, fig. 2b; Pl. VIII, fig. 6a). The latter of these exhibits
an interesting abnormality in which the first interbrachial on the posterior side
passes down to the basal, producing an anal area similar to that of the Actino-
crinide (PI. VIII, fig. 6b). The case is the converse of that of the abnormal
Teleiocrinus mentioned by Wachsmuth and Springer‘ in which the anal plate
between the radials is lacking, as in the Melocrinide.

In the matter of surface sculpture in this and other species found in the
Ross limestone, the observer must be on his guard against the effects of
chemical action and weathering, by which the aspect of the plates is sometimes
completely altered. Often the original calcareous surface is destroyed, while
certain structures, such as the channels, or ridges connecting the plates, are
replaced by silica, leaving an abrupt and rugose ornament totally different

1The North American Crinoidea Camerata, Mem. Mus. Comp. Zool. Harvard, vol. 20, p. 56, 1897.

54 SMITHSONIAN INSTITUTION

from that of the unaltered plates; the latter may often be seen when exposed
by cleaning in a part covered by matrix, so that the two kinds of surface
appear in the same specimen. See, for example, the specimen of S. pratteni
figured on Plate VIII, figures 2a, b.

Free specimens of the bulbous roots are not abundant at the pyburnensis
locality ; the few obtained are much smaller than those associated with pratteni.
Hall described Camarocrinus saffordi and C. clarki upon material from this
region, but as there is no evidence to indicate with which of several calices
either of them is associated, the names cannot be utilized for any of these
species.

Types.—In the author’s collection.

Horizon and locality—Helderbergian; Ross limestone of the Linden
formation, in blue limestone and associated cherty beds for 30 or 40 feet up
from the water’s edge, Pyburn’s Bluff, Hardin County, Tennessee.

7. SCYPHOCRINUS ULRICHI (Schuchert)
Plate IX, figs. 2a, b
1903. Camarocrinus ulrichit Schuchert; Amer. Geologist, vol. 32, October, p. 239.
1904. Camarocrinus ulrichi Schuchert; Smithson. Misc. Coll., vol. 47, pp. 263, 271, pl. 4o,
figs. 6-8; pls. 41-43, and text-figs. 43, 44.

Calyx large, ovoid, the larger end below, spreading by a very broad angle
from the base; widest about the second range of interbrachials, and con-
tracting slightly from there to near the zone of arm-bases. Plates flat, or low-
convex, some with pustulose center; lower interbrachial areas rather unevenly
and obtusely swollen, posterior area the largest. Secundibrachs relatively
narrower and longer than in S. pratteni, and apparently less than 10 in number.
Arms and stem unknown.

Dimensions of type specimen: Height of calyx, 62 mm.; greatest width,
50 mm.; width toward arm-bases, 43 mm.

This species is represented by a single calyx, found in the talus of beds
containing numerous Camarocrinus, to which Mr. Schuchert has given the
above specific name. As many of these are very large, it is assumed that they
appertained to individuals of this species rather than of the smaller S. gibbosus.

Owing to the surface condition of the rather flat plates, it is difficult to
identify the interbrachials in some places, but it is evident that the modification
of the lower pinnules due to fixation has proceeded much farther in this than
in the other species—so far in fact that all semblance of pinnule arrangement
is lost. At the same time there is an entire absence of the surface sculpture
produced by ridges or pits, so that the conspicuous pavage of the other species
is absent here. The secundibrach series leading to the first arm bifurcation is
also much less distinctly rounded.

CRINOID GENUS SCYPHOCRINUS 55

While distinctly of the type of S. pyburnensis, the zone of greatest width
is much lower, and the basal expansion of the calyx at a considerably wider
angle. The low, flat plates and absence of distinct sculpturing also distinguish
it, although this character must not be too much depended upon as the appear-
ance may be due to erosion.

Holotype.—In U. S. National Museum.
Horizon and locality.—Helderbergian; Haragan limestone, near Dough-
erty, Oklahoma.

8. SCYPHOCRINUS GIBBOSUS n. sp.
Plate IX, figs. 3a, b

Calyx small, broadly spheroidal below, widest about the middle, contract-
ing toward the arm-bases. Base very small. Interbrachials not protuberant.
Plates highly tumid, with strong connecting ridges and pits.

Dimensions of type specimen: Height of calyx to I[Brs, 25 mm.; width
at IIBr, 30 mm.

A single imperfect calyx found in the Camarocrinus horizon of Oklahoma
suggested the proposal of this species; it is preserved only to the height of the
third secundibrachs, and the basal plates are wanting. Among the Hardin
County, Tennessee, material from the Pyburn’s Bluff locality, there are three
small specimens of about the same size as this agreeing in the characters noted,
one of them a perfect calyx, which I have figured for comparison, Plate VIII,
figure 7. They have the facies of S. pyburnensis, without the projecting inter-
brachials, the absence of which, however, may be a juvenile character. The
two forms are evidently of a closely similar type, but whether identical can
only be determined by discovery of better material from the Oklahoma locality.

Holotype.—In the U. S. National Museum.
Horizon and locality.—Helderbergian; Haragan limestone, Franks, Okla-
homa, and (?) Hardin County, Tennessee.

CRINOID GENUS SCYPHOCRINUS 57

EXPLANATION OF PLATES

All figures, unless otherwise noted, are made from light prints of photographs direct
from the specimens, finished with India ink brush drawings. They are reproduced by
the heliotype process. Enlargements, if any, are indicated by an improper fraction placed
at the right lower corner of each figure; if not so distinguished the figure is of natural
size. All specimens, not otherwise noted, are in the author’s collection.

58

SMITHSONIAN INSTITUTION

SCYPHOCRINUS

PLATE I
ScYPHOCRINUS ELEGANS Zenker............. (i ire.
Helderbergian. Cape Girardeau, Missouri

The principal slab described in the text, about 120 by 165 cm. (4 by 5.5 ft.) in size.

It contains about 24 crowns, of which 18 have a large part of the arms intact.
Those which have been specially used for the descriptions and figures are
indicated by letters 4 to G. At H and J may be seen two Camarocrinus bulbs
with the stemless side exposed; at L and K are parts of other bulbs broken by
pressure and partly imbedded. For convenience of measurement a scale is added.
Reduced by photography to 3.

Photographed by Dr. R. S. Bassler of the National Museum, and somewhat
retouched by Mr. Chapman.

The slab is from a limestone layer about 4 to 6 inches in thickness, resting
upon a parting of shaly clay.

The specimens now visible were all partly imbedded in the underlying soft
clay layer, being attached to and gradually passing into the firm limestone above,
which for a thickness of about 2 inches is entirely composed of broken remains
of stems, crowns, and bulbs. In studying this photograph it must be remembered
that the surface now seen was the under surface of the slab as it lay in the
formation, and that the aspect of the fossils is that of their lower side as they
settled into the sea bottom.

Author’s collection. Now mounted in the Hall of Invertebrate Paleontology,
U. S. National Museum.

SPRINGER SCYPHOCRINUS

SCALE OF (Pe lzl=a7

SSS Se eee

RS Bassler Photo. KM Chapman dé

Laue
Pity te
sey anny

ay ‘t 0

ey | :

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Ae
Ap ain} hur

yh

5)

Oh ie i
oe

60 SMITHSONIAN INSTITUTION

PLATE II
SCYPHOCRINUS | ELEGANS) Zenker. cysts sister tye etal

Specimens B and C of the slab shown on Pl. I. Natural size
Fic. 1, specimen B; fig. 2, specimen C. To show the various types of surface sculp-
turing, both on lower calyx plates and in the interbrachial pavement.
In fig. 1 (B) the appearance of suspended chains is most prominent
(var. schlotheimi). In fig. 2 (C) it is a complicated network into which
enter root-like prolongations from the lower elevated brachials (var.
schroeteri) ; and at the lower left edge the coste are broken up into

separate granules, as described under S. decoratus W. and J.
Photographed by Dr. R. S. Bassler and carefully retouched by Mr.

Chapman.
Helderbergian. Cape Girardeau, Missouri.

SPRINGER SCYPHOCRINUS

Heliotype Co Boston

ne

rc

62

SMITHSONIAN INSTITUTION

PLATE III

SCYPHOGRINUS ELEGANS Zenker-no sec neni lae eee

Fic.1. Specimen A, from the slab on Pl. I. A nearly complete crown with calyx

about 10 cm. high, and arms to about 25 cm. in length; part of base
and proximal columnals in outline. Calyx but little flattened, and show-
ing about the normal contour ; interradial view. Interbrachial pavement
has the stellate type of sculpturing produced by progressive coalescence
of the slits crossing the sides of the plates; these disappear in the upper
part where the surface becomes nearly smooth; this is not due to any
erosion in the fossil state, as these parts were covered with a fine
calcareous mud which was carefully removed with delicate tools and
water. From the calculated taper of the arms to the highest part
visible, it is probable that they were at least twice as long as here
preserved. Reduced to2.

2. Detail from specimen F (PI. I), with the smooth type of interbrachial pave-
ment. Natural size.

3. Detail from specimen FE, interradial view, showing interbrachial pavement
with slits crossing margins of plates at the sides in lower part, and
depressions at angles in upper, producing both stellate and reticulate
sculpture (var. typica). Natural size.

4. Detail from specimen G, upper part of interbrachial pavement, showing
depressed areas at corners of plates disconnected in one area, and con-
nected in the other, producing reticulate (var. typica) and banded (var.
schlotheimi) sculpture in the same specimen. Natural size.

Helderbergian. Cape Girardeau, Missouri.

GEYPTOGRINUSsDVERT Elall bea eye eee tus e rT ne

(For comparison of fixed pinnules)

5a. R. ant. iR view of calyx, showing the fixed pinnules on IIBr 2-4-5-6-7,
their course marked by sharp median ridges. Natural size.
5b. Tegmen of same, showing probable nature of the Scyphocrinus tegmen.
The fixed pinnules are seen curving upon and merging into the tegmen.
Anal series in strong median ridge also merging into the tegmen. The
lower part of the tegmen is distorted by an imbedded stem frag-
ment. xX.
This figure should be compared with Pl. IV, fig. 1.
Ordovician. Cincinnati, Ohio.

YPHOCRINUS

NGER Sc

4

SPR

Liat)

ae Fe ‘
HEREIN

64

FST Gite

Io.

1S

SMITHSONIAN INSTITUTION

PLATE IV
CALYX PLATES, PINNULES, AND SCULPTURING
(All figures natural size unless otherwise stated)

SGYPHOCRINUS ELEGANS Zenkern see oie enero

A composite figure, constructed from the original of fig. 1, Pl. V, and speci-
mens A, B, C, D, E, F, G, of the slab shown on PI. I.

To show development of the fixed pinnules, and the way in which
they lose their identity by the progressive change in surface sculpturing
produced by modification of fine grooves and costz in lower part into
stronger depressions and ridges upward, until the appearance becomes
that of transverse bands suspended between the rami, instead of longi-
tudinal series. In one ray and part of an interradius the surface orna-
ment is omitted, and to facilitate identification the pinnulars are left
unshaded while the interpinnulars and intersecundibrachs are indicated
by diagonal hachure. Thus the succession of pinnules upon IIBr
2-4-5-6-7 is shown, until at about the eighth IIBr the interpinnulars
disappear, and from there on the pinnules are packed in close lateral
contact. The distal ends of the pinnules from the IIBr and lower IIIBr
bend over and become merged in the tegmen, as shown in PI. III,
fig. 5b. The extreme relative shortness of the IIIBr is well shown,
and also the manner in which the first few pairs of them are joined by
their inner margins. The limit of the calyx distally is seen to be
approximately just above the level of the IIIBr axil.

Part of a ray from IBr, to bifurcation at IIBr,,; showing the various
styles of sculpturing at different levels caused by progressive changes
in the size and form of pits and ridges passing from plate to plate.
Made from specimens A and E.

Portion of the right side of interradius above ilIBr; showing the change
in superficial appearance of the interbrachial pavement due to modifica-
tion of the depressed areas at the angles of the plates by lateral coales-
cence into continuous furrows, producing the transverse girdles or
chains. Constructed from specimens A and B, and fig. 1 of Pl. V.

Side view of section of a ramus at the lower IIIBr, with the pinnules
closely abutting proximally by angular faces. x 2.

Cross-section of brachial and pinnule at same level. x 2.

Oblique dorsal view of IIIBr, showing modified articular face of brachial
and connecting pinnules, also the angular faces of pinnulars abutting
upon those of adjoining pinnules. x 6.

8. Cross-section of pinnule on lower IVBr and VBr. x 2.

Cross-section of pinnule at lower VIBr. x 2.

Side view of portion of arm at VIBr between those of figs. 9 and 11, show-
ing pinnules rounded and beginning to be free from their fellows. x 2.

Cross-section at higher VIBr. x 2.

SPRINGER SCYPHOCRINUS

0782:
var 20,
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KM Chapraan dei.

CRINOID GENUS SCYPHOCRINUS

SCYPHOCRINUS ELEGANS Zenker—Continued...........

Fic.12. Cross-section, natural size, of brachials at different heights, to show the
taper of arm; a, IIJBr next above bifurcation, width 6.5 mm.; b, VBr
an inch below bifurcation, and 10 cm. above a, width 2.75 mm.;c, VIBr
15 cm. above b, width 2 mm. All from the same ray. d, a higher
VIBr from a similar specimen, width 1.15 mm., which at the same rate
of diminution would be about 22 cm. above the last. This would give
a length of about 48 cm. (18 inches) from lower IIIBr to a higher
VIBr of about 1 mm. width. As the distal part of the arm would
probably diminish to 5 mm., this would add at least 10 cm., making the
total probable length of arm in life about 55 to 60 cm., or at least
22 inches.

66 SMITHSONIAN INSTITUTION

PLATE V
STEM CHARACTERS

(All figures natural size unless otherwise stated)

SGYPHOCRINUS! ELEGANS) Zenker: byeracis viele cicleielasreciete
Cape Girardeau, Missouri
Fic.1. A free calyx to the height of about IIBr,,, radial view; showing character-
istic surface or ornament; used partly in construction of figures of
Pl. IV. Note the change of direction in the rami at the fifth IIBr.
2a, b, c. a, Cross-section of column proximal to calyx (12 mm. diameter, 13
joints to the cm.) ; showing the extremely wide axial canal (lumen)
and the short alternating columnals. x 2.
b, Joint-face of same, showing pentagonal outline of lumen, and
contact area forming the rim of the intercolumnal chamber (ligament
fossa) bordering it, with the radiating crenule traversing both. x 2.
c. Oblique view of same joint-face, further enlarged, with vertical
section ; to show the small remaining points of stellate lumen at angles
of the pentagon, and the relative thickness of the columnal from the
periphery to the flange-like part extending inward as a diaphragm
between the chambers. x 8.
3a, b, c. Similar views of section at median part of column (8 mm. diameter,
8 joints to the cm.); showing much narrower lumen, with stellate
radiations in the part of the columnal forming the diaphragm.
Figs. a and b X 2;¢ xX 6.
4a, b. Similar views of section near distal end of stem (6.5 mm. diameter,
5 joints to the cm.); showing smaller stellate lumen, with thicker
diaphragm. x 6.
5. Oblique view with vertical section of columnal of intermediate type toward
the distal end, having relatively narrow chamber and small stellate
lumen. x 6.

SCYPHOCRINUS ULRICHLI® (Schuchert)ieriiaeiiireeere ee ee
6. Distal end of stem with branches merging into a plated area within the
collar (broken away), being the upper part of a large bulb (not
included in figure) ; showing the small stellate lumen, and position of
large openings at bifurcations, leading to the chambers. U.S. National
Museum.
Helderbergian. Dougherty, Oklahoma.

AANCYROGRINUS BULBOSUS Hlall occ ic.c cre cteieis ats oteleyesstel sieteye
7, 8. Different forms of anchor-like distal end of the stem, with its four
grapnels.
g. Proximal view of another specimen showing the quadripartite stem lumen.
10. A transversely fractured specimen showing how the stem extends to the
bottom of the terminal structure.
Hamilton Group; Middle Devonian. Clark County, Indiana.

SPRINGER SCYPHOCRINUS

WAY

-ln

WW

KM Ghapraan del.

10

68

SMITHSONIAN INSTITUTION

PLATE VI
(All figures natural size unless otherwise stated)

ScyYPHOCRINUS PRATTENI (McChesney)...............205.

Fic.1. The holotype, showing base and lower part of calyx, formerly in the Chicago

Academy of Science, destroyed by fire in 1870. Left anterior radial
view; drawn from a sulphur cast of the original made by Whitfield,
now in the author’s collection.
Tennessee River, Northern Alabama.
2a. A large distorted calyx with rays to IIBr,, from posterior interradius.
2b. Basal view of same; r. post. iR upward; shows the protuberant iBr areas.
2c. Restoration of same, from r. post. R, to show the natural contour, and the
course of the fixed pinnules; iBr and iP from IJBr up marked by
diagonal hachure. Lower part of radial series not shown sufficiently
depressed.
Helderbergian. Hardin County, Tennessee.

SCYPHOCRINUS MUTABILIS( 1. (Spies ecstatic

3a. Lateral view of -eroded calyx from 1. ant. iR; base restored from other
specimens.
3b. Basal view of same; post. iR upward.
(See more characteristic specimens on Pl. VIII.)
4. Fragment showing base; 1. ant. iR upward.
Perry County, Tennessee.
5a-d. Detached fragments of calyx, not known to be from the same individual,
arranged in natural order; to show sculpturing of plates.
5e. Part of ramus above axillary IIBr from a larger individual.
6, 7. Detached bases, to show cost and grooves at margin of plates.
8, 9. Plates of interbrachial areas, to show sculpturing.
10-14. Separate plate showing surface sculpturing in different parts of the calyx.
15, 16. Edges of lower calyx plates, showing grooves or folds upon the margin,
but not penetrating the plates.
17. Similar view of plate enlarged. x 2.
18, 19. Inner floor of plates from different parts of the calyx, showing the
sculpturing on the inner surface.
Helderbergian. Benton County, Tennessee.

SPRINGER SCYPHOCRINUS Prete VI

pet oi.

/, gare

Ws
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ape

7O SMITHSONIAN INSTITUTION

PLATE VII
(All figures natural size unless otherwise stated)
ScyPHOCRINUS PRATTENI (McChesney)...................

Fic. 1a. Left anterior interradial view of a maximum specimen with one ray at
extreme left preserved to the axillary IIBr; showing the extreme pro-
tuberance of the iBr areas, and depression of the radial series ; also the
contraction in width of calyx toward the arm-bases. Short pustulose

spines, irregularly scattered, are shown.

1b. Basal view of same, 1. ant. iR side up.

Helderbergian. Hardin County, Tennessee.

ScYPHOCRINUS PYBURNENSIS n. [S) OS

2a. Right anterior radial view of the principal type specimen with rays com-
plete to the arm-bases, showing general contour of the calyx and
character of the unweathered sculpture of the plates; the radiating
coste coalesced into a single large ridge in upper part, producing
stellate ornamentation much modified upward by secondary growth.
In the matrix above the crinoid may be seen a portion of a Camaro-
crinus bulb which was imbedded in the limestone.
2b. The same specimen from r. post. R, on which the sculpturing appears
sharper from weathering, and the action of alge in deepening the pits;
the course of the fixed pinnules can be readily traced. The asymmetry
due to the greater distension of the anal interradius is well shown.
3. Basal view of another specimen, posterior interradius above; showing the
slight protuberance of the interbrachial areas, and the numerous con-
necting ridges in lower plates.
Helderbergian. Hardin County, Tennessee.

SCYPHOCRINUS |STELLATUS (Elall)) Merci toniverteriecict

4a. Lateral interradial view of distorted calyx with plates below axillary IBr
wanting. x 3.
4b. Oblique basal view from another side, showing the relatively narrow and
long IIBr as far as the bifurcation. Basal parts restored. x $.
Helderbergian. Keyser, West Virginia.

r
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SPRINGER SCYPHOCRINUS

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72

SMITHSONIAN INSTITUTION

PLATE VIII
(All figures natural size unless otherwise stated)
SCYPHOCRINUS PRATTENI (McChesney)

Fic. 1. Left anterior radial view of somewhat compressed specimen, showing the

surface characters of the plates, which have pustulose elevations irregu-
larly in lower part. The secundibrachs are seen in the ray to the right
up to the axillary. Some small knobs along the sutures in the upper
left corner may be silicious deposits made during fossilization, which
in some cases greatly modify the surface.

2a. A small specimen in which the calcareous test has been largely replaced by
silica, and much of the original surface destroyed by chemical action,
producing an unnatural rugosity of the sculpturing. The specimen is
uncompressed, and shows perfectly the characteristic contour of the
species.

2b. Basal view of same, showing some unweathered plates in which the original
smooth surface is preserved ; small spinous pustules are well represented
on the lower plates in both views.

Helderbergian. Hardin County, Tennessee.

ScYPHOCRINUS MUTABILIS n. sp

sole) elele) vie ein! e/le che) sje selisiieleialelle

3. A short specimen; from left anterior radius with surface in natural condi-
tion, having the turbinate contour of average specimens; sculpturing
in interbrachial regions greatly modified by secondary growth.

4. A more elongate specimen; from left anterior radius with lower part of
calyx less regularly conical; sculpturing intensified by weathering.

5. A strongly turbinate specimen; with surface studded with small knobs upon
the suture lines perhaps produced by silicious deposits during fossiliza-
tion. Lower part restored from other specimens.

Niagaran to Helderbergian. Hardin, Perry, and
Benton counties, Tennessee.

SCYPHOCRINUS PYBURNENSIS n. sp

6a. Abnormal specimen; lateral view of calyx, showing the fixed pinnules.

6b. Basal view, showing 6 plates in the radial circlet; posterior interradius up.
The posterior interbrachial passes down to the basal which is truncated
to meet it, producing an anal area similar to that of the Actinocrinide.
Slightly enlarged.

Helderbergian. Hardin County, Tennessee.

7. A small specimen, probably of this species, figured for comparison with

figs. 3a, b, of Pl. IX.

SPRINGER SCYPHOCRINUS

wD

uhaprodn del.

KM.G1

74

SMITHSONIAN INSTITUTION

PLATE 1X

(All figures natural size unless otherwise stated)

SCYPHOGRINUS) SPINIFER) NuiSPs sj a-letiscle eee

Fic. 1a. The holotype as seen from the side originally exposed, showing a few

scattered spines on the weathered surface in the median area, and the
fringes of long spines at either margin, some of them forking, which
have been brought to view by cleaning. Note the parallel position of
the spines in each cluster. x}.

1b. Opposite side of the specimen as exposed by cleaning, showing the sharply
sculptured plates and the numerous slender spines extending to the
region of the arm-bases ; many of them enlarging distally, some forking,
and others tapering to a point. Some are seen partially detached from
their sockets. x 4.

1c. Detail from same view as last, further enlarged. x 3.

Helderbergian. Hardin County, Tennessee.

SCYPHOCRINUS) ULRICHT-: ((Schuchert) has. e ese eeme

2a. Left posterior radial view of holotype; a large, broadly ovoid specimen,
with calyx intact to the lower I]]Br. The fixed pinnules are greatly
modified, leaving little semblance of their primitive form. U. S.
National Museum.

2b. Basal view of same; 1. post. R upward.
Helderbergian. Dougherty, Oklahoma.

SCYPHOCRINUS) GIBBOSUS/NS Spin-seeeion eset

3a. Left anterior interradial view of holotype, an imperfect calyx preserved
only to IIBr,. x .
3b. Basal view of same, post. iR upward; the basals, which were very small,

are wanting. xX.
Helderbergian. Franks, Oklahoma.

PLILOSARCUS! BREVICAULIS: Nutting. virions

4. Specimen of this Recent Pennatulid; for comparison, to show the form and
proportion of its bulbous root. No. 30057, U. S. National Museum.
Tsiuka, Japan: 44 fathoms.

MARSIPOCRINUS TENNESSEENSIS (Roemer)...............-.:

5a. Complete tegmen with arms and pinnules attached; r. ant. iR-upward.

55. Detail of same enlarged; parts of r. ant. and r. post. rays, showing the
regular brachial pinnules, and the interbrachial pinnules at either side
of the arms, with the ambulacra leading to them in the positions where
the pores are seen in text-fig. 19. X 3.

Silurian. Decatur County, Tennessee.

MaRSIPOCRINUS STRIATUS? Wachsmuth and Springer............

6. Unretouched photograph of part of tegmen of specimen from which text-
fig. 19 was made, showing the ambulacra, and openings for fixed
pinnules.

Silurian. Decatur County, Tennessee.

SPRINGER SCYPHOCRINUS

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