r

/B E R K E L E Y

LIBRARY

UNIVERSITY OF
'v CALIFORNIA

EARTH

SCIENCES
LIBRARY

LIBRARY CATALOGUE SLIPS.

Illinois. (Geological Surrey,)

Geological Survey of_ Illinois, A. H. Worthen, Director. Volume vm. Edited
by Josua Lindahl, Ph. D., State Geologist— Plates.— Published by authority of
the Legislature of Illinois July, 1890.
8vo. Plates I-LXXVDI, and explanations.

"Worthen, (Amos H.)

Geological Survey of Illinois, A. H. Worthen, Director. Volume VIII. Edited
by Josua Lindahl, Ph. D., State Geologist— Ptates.-Published by authority of
5 the Legislature of Illinois. July, 1890.
< 8vo. Plates I-LXXVEH, and explanations.

6

•g Palaeontology.

Geological Survey of Illinois. A. H. Worthen, Director. Volume VIII. Edited
•J, by Josua Lindahl. Ph. D,. State Geologist-P/afes.-Published by authority of
« the Legislature of Illinois, July, 1890,
fi 8vo. Plates I-LXXVIII. and explanations.

GEOLOGICAL SURVEY OF ILLINOIS,

A. H. WORTHEN, DIRECTOR.

VOLUME VIII.

GEOLOGY AND PALEONTOLOGY,

Edited by JOSUA L1NDAHL, Ph. D., State Geologist.

GEOLOGY,

BY A. H. WORTHEN.

BY A. H. WORTHEN, CHARLES WACHSMUTH, FRANK SPRINGER.
E. O. ULRICH AND OLIVER EVERETT.

WITH AX APPENDIX.

TEXT.

PUBLISHED

BY AUTHORITY OF THE LEGISLATURE OF ILLINOIS.
JULY, 1890.

C\Q

.\ft

EARTH

ILLUSTRATED

BY E. O. ULRICH,
NEWPORT, KENTUCKY.
~T

FEINTED

BY H. W. ROKKER,
SPBINGFIELD, ILLINOIS.

TABLE OF CONTENTS

Table of Contents iii-iv

Letter of Transmittal v-xi

PART I. GEOLOGY.

CHAPTER I.
Drift Deposits of Illinois, A. H. WORTHEX 1-24

CHAPTER II.

Economical Geology (Coal: Natural Gas and Oil; Artesian
Water), A. H. WORTHEX 25-67

PART II. PAL.EOXTOLOGY.

SECTIOX I.
Description of Fossil Invertebrates. A. H. WORTHEX (>9-154

SECTIOX II.

New species of Crinoids and Blastoids from the Kinder-
hook group of the Lower Carboniferous Rocks at Le-
Grand, Iowa: and A new genus from the Niagara group
of Western Tennessee, CHARLES WACHSMUTH and FRAXK
SPRIXGER 155-208

SECTIOX III.
American Palaeozoic Sponges, E. O. ULRICH 209-241

SECTIOX IV.

Sponges of the Devonian and Carboniferous Systems. E.
O. ULRICH... ...243-251

IV

SECTION V.

Descriptions of Lower Silurian Sponges, E. O. ULRICH and
OLIVER EVERETT 253-282

SECTION VI.

Palaeozoic Bryozoa, E. O. ULRICH 283-678

Index to Part I 689-691

Index to Part II, Sections I, II 693-699

Index to Part II, Sections III, IV and V... 701-706

Index to Part II, Section VI 707-727

Table of Contents to Part II, Section VI 728

Plates I-LXXVIII and explanations.

APPENDIX.

The Private Life and Scientific Works of PROF. AMOS HENRY
WORTHEN, by N. W. Bliss and C. A. White, with a portrait
of Prof. Worthen, by Jacques Reich 3-37

General Index to Geological Survey of Illinois, A. H. WOR-
THEN, Director, Vols. I-VIII, by Josua Lindahl 39-151

Approximate Geological Map of Illinois.

LETTER OF TRANSMITTAL.

To His Excellency, JOSEPH W. FIFER,

Governor of Illinois:
Sm:-

I have the honor to submit herewith the Eighth Volume
of the Geological Survey of Illinois.

This volume, exclusive of the "Appendix," was prepared by the
late Professor A. H. WORTHEN, in accordance with an Act of the
Thirty-Fourth General Assembly of the State of Illinois, ap-
proved June 27, 1885, which provided ''That the Curator of
the State Historical Libraiy and Natural History Museum, who
is required to perform such duties as may be by Jaw required of
the State Geologist, shall during the ensuing two years, collect

and pi'epare for publication a volume to be entitled Volume 8

of the Geological Surrey of Illinois." For certain reasons the
contract with the State Printer was not signed until late in
1888, and in this interval Professor WORTHEN had died, May
6th, 1888. My commission as his successor, bears the date of
June 9th of the same year, and it became my duty to edit this
volume.

The printing was commenced early in 1889. Neither I, nor
any of the authors could have foreseen that more than a year
and a half would be needed for its completion. The new

VI

genera described in Part II, Section 3, bear the date of 1889,
which, as it now happened, is apparently a case of antedating.
However, as all the new species in the volume were recorded in
Mr. S. A. MILLER'S "Korth American Palaeozoic Fossils," which
work was published in November, 1889, this may be taken as
an excuse for omitting corrections of the above dates, in the
"Errata."

The plates illustrating Part II, were printed before Prof.
WORTHEN'S deach. Mr. CHAS. K. WORTHEN made the origi-
nal drawings for plates IX-XXV1II, the remaining 58 were drawn
by Mr. E. 0. ULRICH, who also contracted for and lithographed
all the 78 plates. The KREBS Co. did the printing. Mr. ULRICH
informs me that a strike among the pressmen, and the conse-
quent necessity of employing inexperienced hands hi printing
plates XXXVIII-LX, was the cause of the less satisfactory ap-
pearance of these plates.

As this volume not only forms the final report of the Geo-
logical Survey of Illinois, but also represents the last work of
its venerable Director, it seems appropriate to close these eight
volumes with a biographical sketch and portrait of Prof.
WORTHEN, and to add a general index to the entire series of
his reports.

Mr. N. W. BLISS, Attorney at Law, a near relative of the de-
ceased and his most intimate friend from childhood, was re-
quested, at the suggestion of Prof. WORTHEN'S family, to sketch
his private life, and Prof. C. A. WHITE, M. D., of the United
States Geological Survey, to likewise treat the scientific work of
Prof. WORTHEN, and both of them willingly responded. Their
sketches will be found in the "Appendix."

It is my pleasant duty hereby to render thanks officially to the
heirs — the 6 sons— of Professor WORTHEN, who defrayed all ex-
penses for the excellent portrait of their lamented father, which

VII

adorns the "Appendix." The original pen-and-ink drawing; by the
eminent artist JACQUES REICH, of New York, which drawing is
the property of this office, was placed at their disposal for the
purpose of being reproduced.

The index of the PAL^OCRINOIDEA in Vol. VIII, Part II, Sec-
tions 1 and 2, was revised by Mr. CHARLES WACHSMUTH, and
those of the SPOXGLE and BRYOZOA in Sections 3-6, by Mr. E.
0. ULRICH. In preparing the "General Index," I at first simply
consolidated the indices of the eight volumes into one. But
finding that such a consolidation would by no means answer
the purpose, I undertook to revise every item and make numer-
ous additions and re-arrangements, as well as orthographic
corrections of pateontological names. This extremely tedious
and time consuming work was done last fall when I had reasons
to hope that the volume would be published before the end of
last year. The index is therefore less elaborate than I would
have made it, had I known then that I could spend much more
time on it without delaying the printers. As it is, I trust it
will still be found of value.

The Geological Map of Illinois, published in 1875, and distri-
buted with Vol. VI. of these reports, has long been out of print,
and I have been unable to fill the frequent requisitions from
scientists, schools, libraries and private applicants, most of
whom have stated that they have the set of reports but not
the map. I have therefore added to this volume a reproduc-
tion of the old map but on a smaller scale (32 miles =1 inch
—the scale of the old map being 6 miles =1 inch) and with
the geological formations represented by a system of lines of

•

shading, instead of by colors. Although the map is copied
with as much accuracy as was regarded practicable and desir-
able, I have prefixed the word "Approximate" to its title.
It is evident that even the original map was never intended to

— B

'VIII

be considered as more than an approximate representation of
the areas of geological formations in the State. An accurate
geological map of the State is still a desideratum.

In this connection I beg to make a few suggestions for some
of the most important work that the State ought to undertake
as a continuation of its Geological Survey. In part these sug-
gestions are the same as those I had the honor to make in
my report to your Excellency and the Board of Trustees
of the State Museum, in January, 1889. They were also used
as the substance of two bills introduced in the last Assembly of
the State Legislature, but, although seemingly meeting the apt
proval of the Legislature, were "tabled" at the third reading.
I would suggest:

1. That a continued collection be made of logs of all borings,
shafts, etc., in the State. Owing to the imperfect character of
the records of such undertakings, as usually made, each locality
where a boring or sinking of a shaft is in progress should be
visited, or, at least, arrangements should be made with those
in charge of the work, for the proper preservation and identi-
fication of samples of the strata.

2. That a detailed topographic, or at least hypsometric survey
of the State be made on a plan conforming to similar surveys
already made, either wholly or in part, by New Jersey, New
York, Massachusetts, Wisconsin and Michigan, and now in pro-
gress in Pennsylvania and Minnesota.

Thus would be furnished the necessary data for elucidat-
ing many problems of the greatest economical import-
ance to such industrial pursuits as require a correct insight into
the geological structure of the State. I would therefore suggest:

IX

3. That the facts thus obtained, and further supplemented,
when necessary, by local investigations, be used as the basis of
a series of either annual or biennial reports on the Geology of
Illinois, with special reference to the underground topography
of the different coal beds, water bearing-, and other strata,
showing their distribution and depth below the surface in. the
various parts of the State.

It is pretty well settled that our coal beds were not laid down
in broad sheets of even thickness over large areas, but were
formed on the low lands of the then surface, while the higher
portions were left bare. The investigation, above suggested,
would go far to indicate the position and extent of these bar-
ren grounds. It would also give the best guidance in deter-
mining where artesian water, oil, gas, etc., may be expected —
or. at least, where they cannot reasonably be expected.

In connection with these investigations particular attention
should be given to the quaternary deposits in the State. Much
interest is being manifested in the glacial geology of the United
States: our State ought to cooperate with her sisters by making
a thorough study of her moraines and other glacial deposits.
The subject is large and has hitherto received little attention.
Indeed, our present knowledge of these deposits in Illinois is
merely rudimentary. We know but little even about the distri-
bution of drift clays, marls, sands, gravels, and other elements of
the "drift." That treasures of incalculable value to our com-
merce and industries lie hidden therein, within easy reach, can-
not be doubted.

Within the last few years many new facts have been brought
to light in connection with the dynamics of the lead region.
Wisconsin has made a very thorough survey of so much of this
region as lies within her borders, and our State should supple-

ment it by equally thorough work in the light of the new facts,
on this side of the line.
I would also suggest:

4. That careful laboratory tests, physical and chemical, be
made of our coals, rocks clays, etc., to ascertain their pro-
perties and adaptability to various uses. The character of the
coal from various mines and veins is continually changing;
yearly analyses with regard to their fuel value should be made
and published. The tests of building-stones should determine
their strength and resistance to frost and hea,t; and their re-
sistance to ordinary atmospheric agencies should be studied at
their natural outcrops and in buildings where they have been
used. The immense importation of cement from other States
and from Europe, in face of the fact that we undoubtedly pos-
sess, within the limits of our own State, excellent raw material,
as well as cheap fuel, for its production at home, in unlimited
quantities, amply warrants a careful investigation of the pos-
sibilities of building up a cement industry in Illinois.

The State possesses many valuable deposits of fire, potter's
and paint clays and of shales, whose properties have never
been tested. These should be analyzed and practical tests made
to ascertain their usefulness. Such tests of the clays of Ohio
and New Jersey may be taken as models.

In order to increase the usefulness of the work already done
by the Survey, and to adapt it to the wants of the people, I
beg, finally, to suggest:

5. That the State should issue, as soon as possible, a sys-
tematic palaeontology, which shall contain a brief description
and, where possible, an illustration of each species found within
her borders, together with its horizon or horizons and a refer-
ence to the work in which the original description may be found.

Such a work as well as all other reports of the State Survey,
including also all maps and diagrams, should be placed on the
market at actual cost by the State, and would, I am sure, meet
with ready sale to students and others interested in the sub-
jects treated in these publications.

I cannot close these remarks without expressing my obliga-
tion to Professor CHARLES W. ROLFE, of the Geological De-
partment of the Illinois State University, at Champaign, for his
valuable suggestions and frequent manifestation of interest in

my work.

I have the honor to be,

Sir,

Your obedient servant,

JOSUA LIXDAHL.

ILLINOIS STATE MUSEUM OF NATURAL HISTORY,
SPRINGFIELD, ILL, July 10, 1890.

PART I.

GEOLOGY OF ILLINOIS,

BY A. H. WORTHEN.

u: r

CHAPTER I.

DRIFT DEPOSITS OF ILLINOIS.

In the preceding volumes of my report on the Geological Sur-
vey of Illinois, no exhaustive discussion of the character and
extent of the superficial deposits of this State was attempted,
because the i. y data were not attainable from an exami-

nation of the natural exposures of the formation alone.

Subsequently, in the development of our coal resources, many
shafts were sunk through the superficial deposits in various por-
tions of the State, which, with other artificial excavations, have
afforded all the - y data for a more comprehensive treat-

ment of the subject: and some of the most instructive sections
of the drift deposits obtained in this way we shall present in
detail in the following pa-

These deposits consist mainly of clay, sand and gravel, which
oread uuconformably over the stratified rocks, covering
them to the depth of from ten to more than three hundred and
fifty feet. Over large aivus in the central portions of the State
they extend far below the drainage level of the streams, and
consequently only the upper portion of the deposit can be seen
in the bluffs and' banks of the water com-

The drift deposits are important in an economical point of
view : Fhft— Because they determine the character and produc-
tive capacity of the soil upon which all other industries are
!y dependent. Soils consist mainly of pulverized rock, to
which is added such organic substan result from the

growth and decay of animal and vegetable organisms upon the
surface, and the soils of Illinois, being the result of disintegra-
tion of the limestones, sandstones, shales, etc., which constitute
the various paheozoic formations of the Mississippi valley, con-
tain all the essential mineral ingredients that are required to
constitute a soil of surpassing fertility.

2 DRIFT DEPOSITS OF ILLINOIS.

Second— The drift deposits are also the main source of our
water supply, and of those homely but indispensable products,
sand, clay and gravel, which enter so largely into the industrial
pursuits of the laboring classes. Every man who sinks a well,
digs a cellar or a ditch, or grades a roadway, penetrates this
formation, and hence it becomes the one with which the people
are most frequently brought in contact, and therefore the one
in which they are more directly interested than in any other of
the geological formations.

In order to arrive at a satisfactory solution of the phenomena
presented by the drift deposits, it will be necessary to consider,
briefly, the condition that prevailed at the commencement of
the period which they represent.

At the close of the carboniferous era, nearly the whole area
of the State of Illinois, as well as that of the adjacent States
on the north and east, was elevated above the ocean's level,
beneath which it has not since been submerged. During all thai
vast period of time, during which the Jurassic, Cretaceous and
Tertiary formations were deposited over such portions of the
continent as were still beneath the ocean, nearlv the entire area
of Illinois was above the ocean's level, and subject to the erosive
agencies that are always prevalent upon the land.

During the earlier portion of this period, the river valleys
were excavated, as well as others that are now filled with drift
material, the existence of which is entirely unknown and unsus-
pected until revealed by artificial excavations. The eroding-
forces of this period were not confined to the excavation of the
river valleys, but they carried away a vast amount of solid
rock strata, not only from the northern portion of the state,
where the evidence of erosion is most apparent, but probably
over nearly the whole area of the state as well.

Prof. D. J. Whitney7, in his report on the lead region, in the
first volume of the geology of AVisconsin, estimates the amount
of solid rock strata removed by erosive agencies over the region
south of the AVisconsin river, at three hundred and fifty to four
hundred feet, and it is highly probable that even this estimate,
large as it may seem, does not fully represent the extent of the
erosion that has taken place not only in northern Illinois, but
over the greater portion of its entire area.

DRIFT DEPOSITS <»F ILLINOIS. 3

The Niagara limestone, that caps the mounds in JoDa
county, was no doubt continuous over the whole of that and
adjacent counties, and it is also highly probable that the Hamil-
ton shales. whirh now overlie the Niagara in the vicinitv of
Milwaukee, originally extended wes' to unite with the

\ onian beds of northern Iowa, and hence the full extent of
the- erosion to which the northern portion of Illinois and the
adjacent regions in Wisconsin and Iowa was subjected, may far
• •ed the estimate of Prof. Whitney, as it probably embraced
all the palaeozoic rocks from the top of the Devonian to the
middle of the Calciferous formation inclusive.

Moreover the occurrence of Cretaceous fossils in the drift clays
point to the existence of deposits of this age far beyond the
known limits of this system, and it is almost certain that ex-
tensive deposr a raceous strata have been swept away by
erosive agencies in the region now under consideration.

These marine organisms may be properly termed "intrusive
-ils." and belong to an age far more remote than the beds
of clay and sand from which they were obtained, and they seem
to show conclusively that beds of fretareous. and possibly of
Tertiary age as well, once extended over areas in the Mi>
sipni valley, where they do not exist 772 situ, at the present time.
Whether these marine strata extended generally over a lanre
surface ami. or were confined to the valleys of the main water
courses, is an unsettled problem.

The specimens figured on the following page embrace three or
four species of shark's teeth, fragments of an Ammonite, a
Bekmnite and an Ecbinoid. The last three, and the tooth of
Ptrrboilu*. are undoubtedly of Cretaceous a ire. and were found in
the boulder clay far above the flood plain of the Mississippi
river.

Figures 1. 2 and 3 represent forms that may belong to a
later period and were found in the sands of the Mississippi val-
ley, h s^ems probable that the valleys of our great rivers may
have been partially filled with Tertinry deposits before the drift
clays \\ere laid down, and that the strata of this age may still
form the lowest beds under the alluvial deposits of the Missis-
sippi and other large rivers of the Xorthw

DRIFT DEPOSITS OF ILLINOIS.

These fossils show so little of the wearing effects of transpor-
tation, as to impress one with the conviction that they were
derived from strata originally deposited at a locality not very
remote from the places where they were found.

The following wood cuts represent the fossils now in the
author's possession, that were obtained from the drift clays of
Illinois, Iowa and Missouri.

Nos. 1, 2 and 3 belong to the genus Lainna, a genus com-
mon to the Chalk and to the Eocene Tertiary. No. 8 belongs,
apparently, to the genus Oxyrhina, and closely resembles O,
crassa, Agassiz.

DRIFT DEPOSITS OF ILLINOIS. 5

Xo. 1 was found on Skunk river, near its mouth; No. 2, in
the river sand at Warsaw, 111.; Xo. 3 is embedded in a nodule
of hard ferruginous sandstone, and was found at the mouth of
the DesMoines river: Xo. 8 was obtained near St. Francisville,
Mo., from drift clays above the flood plain of the river.

Nos. 4. ."> and 6 were found in the blue clays of the drift at
Golden Bluff Vineyards, about two miles south of Warsaw, and
their Cretaceous aspect will, no doubt, be readily conceded. No.
4 is a Belemnitv, Xo. 5, a fragment of an Ammonite, and No.
6 is a tooth of Ptychodus polygyrus, of Agassiz, an undoubted
Cretaceous form.

Xo. 7, is a characteristic Cretaceous Echinoid belonging to the
genus Ananchytes, and was found near Petersburg, in Menard
county.

In addition to the Cretaceous fossils above mentioned, I have
seen in the collection of the Hon. Wm. McAdams, of Alton, a
very large shark's tooth measuring nearly three inches in length,
that was found in sinking a well in the valley of the Illinois
river, a few miles above the mouth of that stream, at a depth
of more than twenty feet below the surface; and also the ver-
tebra of a shark found in sinking a cistern on a sand ridge in
the same county, at a depth of fifteen feet, taken out in Mr.
McAdams' presence. This bone has the dark brown color char-
acteristic of the Ichthyic fossils usually found in Cretaceous and
Tertiary strata.

In further proof of the supposition that pre-existing Creta-
ceous strata were broken up and partially redeposited at local
points in the Mississippi valley during the drift period, we may
cite the frequent occurrence of beds of paint and potter's clays
at the base of the drift deposits. These clays are generally
composed of a fine silicious sediment of various colors, that are
KthologicaJly quite unlike the sediments that would result from
the erosion of any of the paleozoic rocks occurring in the adja-
cent region.

Hence it seems highly probable, as has been suggested by Dr.
White, in the Second Geological Survey of Iowa, that the Cre-
taceous deposits once covered a much wider area in the Missis-
sippi valley than they now occupy.

6 DRIFT DEPOSITS OF ILLINOIS.

In the report a.bove cited, Volume 2, page 212, Dr. White
sums up his conclusions as to the probable extent of the Cre-
taceous strata in Iowa before they were subjected to denuding
forces, as follows:

"How far the Cretaceous strata which a-ppear upon the south-
western margin of the region, extend over the remainder of it
unseen beneath the surface now covered with the drift, is not
now known, because no exposures of them are found there. AW
have, however, many reasons to believe that the last named
strata once covered nearly, if not quite, the whole region, and
a large part of them, being all very friable, were removed by
erosion during the Tertiary age, and much more swept away
by glacial action during the drift or glacial epoch, and the re-
mainder are now mostly covered by the drift. Besides more or
less indistinct indications of the correctness of this view, galh-
ered from observations within the region itself, we find traces
of Cretaceous strata at several points within the State of Minne-
sota, extending as far as, or farther to the eastward than the
eastern border of the region under discussion. Frequent expo-
sures of strata of Cretaceous age exist to the southward of it,
and also to a point in Gut.hrie county as far eastward as the
eastern border of this region ; and, although no exposure of
these strata now appear at the surface in the intermediate
space, judging from the uniformity of the surface, and from our
knowledge of the position that the underlying strata must
necessarily assume, it is inferred that the whole intermediate
region originally received deposits of Cretaceous strata continu-
ous with those that now appear.

These Cretaceous strata everywhere, both in Minnesota and
Iowa, show evidence of extensive glacial and other denudation.
This has been accomplished with facility in consequence of the
great softness and friability of all the strata of the age. The
denudation of these strata have been so great that their re-
mains now exist in some parts only as scattered outlines rest-
ing upon older rocks."

The facts observed in Illinois would seem to fully sustain Dr.
White's views in regard to the former extent of the Cretaceous
formation, and it is highly probable that the local patches of
Cretaceous strata may have been deposited as far eastward as

DKIFT DEPOSITS OF ILLINOIS. 7

the borders of the Mississippi valley, and southward until they
united with strata of the same age south of the Ohio river.

After this brief view of the conditions that probably prevailed
during the earlier portion of the drift period, we may now pro-
eeril to note briefly the several subdivisions of the drift deposits.
Taking them up in the descending order, they are as follows:

First — we have the alluvial deposits of the river valleys, or
those below the ordinary flood plain of our large rivers. These
deposits consist mainly of sand and fine silicious sediment, held
in suspension by the water during periods of inundation, and
were deposited over the flood plain as the waters receded to
their ordinary level.

Second— We have the river terraces that were formed in a
similar manner to the river bottoms, but at a time when the
flood plain was from thirty to forty feet higher than at the
present time. Those terraces form eligible sites for man}' of our
river towns, among which we may mention Naples, Meredosia
and Havana, on the Illinois river, and Oquawka and New Bos-
ton on the Mississippi. The terrace ''epoch" is probably nearly
synchronous with that of the loess.

Third — Modified drift and loess. The term modified drift is
applied to beds of sand, gravel and clay that have been formed
from the older members of the series by the sifting process of
wave action or water currents. This deposit generally forms
the upper portion of the river bluffs, and often fills lateral val-
leys on the main water courses.

The bluffs at Warsaw in Hancock county, presents an instruc-
tive section of modified drift and loess. These deposits are
there from forty-five to fifty feet in thickness, and were cut
through in grading Main street to the river landing, showing
the following section:

Ft. In.

Ash-colored marly clay 10

Brown clay 10

Brown sand stratified 8

Blue sandy clay 2 G

Fine gravel and clay 2 6

Yellow sand 2

Gravel and boulders 8

Bluish clay— exposed 5

8 DRIFT DEPOSITS OF ILLINOIS.

On a ravine a short distance south of Main street, the bluish
clay at the base of the above section is filled with fragments
and branches of wood, and a bone, thought by its finder to be
the femur of a human skeleton, was obtained from it, but un-
fortunately was allowed to crumble to fragments from a lack
of the knowledge required to preserve such fragile specimens
from destruction.

The "loess" consists of buff and gray marly sand, and usually
caps the river bluffs, imparting to them the bald, knobby char-
acter so noticeable on the main water courses of the West. Its
maximum thickness in Illinois probably does not exceed sixty
to seventy feet, and is usually much less.

At Quincy, the loess ranges in thickness from thirty to forty
feet, and is underlaid by a foot or more of chocolate colored
clay and a feAV feet of chert and brown clay, (local drift),
derived from the decomposition of the underlying Burlington
limestone. The chocolate colored clay contains twigs and other
vegetable remains, indicating that it was originally a surface
soil, and it is probably the equivalent of the "Forest-bed" of
the Ohio reports.

The loess is not restricted to the vicinity of the rivers, but is
spread over wide areas in the central and southern portions of
Illinois. In the vicinity of Springfield it consists of two beds,
one of brown silicious clay, and the other gray marly sand,
aggregating a thickness of six to eight feet.

In the western part of the county, and the adjacent portion
of Menard, these beds, frequently attain an aggregate thickness
of ten to fifteen feet, according to the statements of professional
well-diggers, and are usually underlaid by a black, mucky soil,
varying in thickness from two to three feet.

The fossils of the loess comprise nearly all common species of
terrestrial, and a few species of fluviatile mollusca, and in addi-
tion to these it has afforded the largest portion of the fossil
mammalia hitherto found in this State. The Hon. Win.
McAdams, who has given especial attention to the fossils of
this horizon, has obtained a fine collection of mammalian re-
mains at Alton and Chester, embracing the bones of the Mas-
todon, Mammoth, Megalonyx, Bos primigenius, Castoroides

DRIFT DEPOSITS OF ILLINOIS. 9

nhioensis and several sp» •<•]»•> of rodents, some of which belong
To extinct species. These discoveries seem to fix the age of the
loess ;is not later than The close of the Pliocene.

The smaller teeth are usually found attached to, or embedded
in. the calcareous nodules that abound in the loess, which are
known under the popular name of "petrified potatoes." Locally
these nodules assume fantastic forms, similar to the common
"clay stones" That abound in the stratified clays of The Con-
necticut valley, and if they were of the same color, could not
be readily distinguished from the New England specimens.

Fourth — The fourth division of the drift of Illinois comprises the
boulder clays. These are usually yellowish at the top and bluish
gray below, and contain numerous boulders mostly of small size,
that are partly derived from foreign material, and partly from
the bed-rock of the adjacent region. This division of the for-
mation ranges in thickness from twenty, to more than a hun-
dred feet, and the embedded boulders vary in size from a few
inches, to two feet or more. Some of these transported ma-
are angular, as though they were embedded in shore ice, and
then transported by water currents to the spot where they
were finally dropped, while most of those of foreign material
are rounded and sometimes striated, as though brought in vio-
lent contact with angular fragments of still harder material.

Trunks of large trees are sometimes met with in sinking wells
through the boulder clay, but no animal remains have been
authentically reported from it, to my knowledge, in this State,
except the Cretaceous fossils illustrated on a preceding
page. The boulder clay is frequently underlaid by a
black, peaty soil, varying jn thickness from two to thirteen
feet, filled in many places with twigs, branches, occasionally
whole trunks of trees, the wood in many cases being in a good
state of preservation.

Fifth — The fifth division comprises the ancient soil above men-
tioned, and the underlying stratified clays and sands, which lo-
cally includes a second soil, similar in character to that imme-
diately below the boulder clays. This division fills the ancient
valleys formed by erosive agencies during the earlier portion
of the drift period, and consequently is somewhat local in its
development.

10 DRIFT DEPOSITS OF ILLINOIS.

The drift deposits, as may be seen by the sections to be found
on the following pages, attain their maximum thickness in the
central portions of the State and thin out to the southward,
all the beds, except the loess, disappearing before reaching the
Ohio river.

Throughout the southern counties of the State, the loess, in-
cluding the sandy marl and the brown clay which lies above
it. with a few feet of local drift beneath it, the whole aggregat-
ing a thickness of ten to thirty feet, are the only remaining
representatives of the drift deposits of Central Illinois. The
local drift appears to be entirely derived from the country rock
on which it rests, for where the underlying rock is limestone, the
embedded fragments of the superincumbent bed will be com-
posed of the cherty material derived therefrom. Where the un-
derlying rock is sandstone or sandy shale, sand and nodules of
sandstone will be found to constitute the main portion of the
overlying deposit.

The sections that are to follow, extend over two-thirds of the
entire area of the State, including the central and northern
portions, where the greatest accumulation of foreign drift occurs.

In Carroll county, on the northwestern border of the State,
the following section of a well in Mt. Carroll, was obtained by
the Hon. James Shaw, and is given in his report on the geology
of that county, as typical rof the drift deposits of that region:

Feet.

Black prairie soil 2

Yellow flue grained clay 13

Common blue clay 2

Reddish clay and gravel 15

Tough blue clay 2

Coarse stratified gravel 3

Pure yellow sand 11

Black mucky clay , 5

Total S3

If there is any representative of the boulder clay in the above
section, it must be the fifteen feet of clay and gravel near the
middle of the section.

In the counties to the eastward of Carroll, Mr. Shaw esti-
mates the average thickness of the drift deposits in Stephenson
and Winnebago counties at about twenty-five feet, while in Ogle
county he places its maximum thickness at "more than a hun-

DRIFT DEPOSITS OF ILLINOIS. 11

dred feet." and lie says, "it is largely composed of coarse gravel
and fine white sand. The gravel beds contain numerous bould-
ers, some of foreign material, and some derived from the lime-
stones of the adjacent region."

In his report on Lee county, the same author gives the fol-
lowing section of a well in the town of Palmyra:

Feet.

Black mcmkl and subsoil 6

Finely- comminuted buff yellow clay 12

Blue compact laminated clay 10

Black muck full of sticks, etc •"•

Total 33

The same author says further: •'Over the southern portion
of the county, the drift clays are probably thicker than in the
vicinity of Rock river. Where thickest, the blue clay is much
the heaviest de-posit, and is often underlaid by the black mud
of the above section, or a bed of gravel and dirt of variable
thickness."

In his report on Whiteside county. Mr. Shaw says, in speak-
ing of the drift deposits: "At one locality, a well was sunk
twelve or fifteen feet through yellow unctuous clay, then blue
clay was struck, and in about fifty feet more a great quantity
' of sticks and wood, apparently cedar and pine, was found. The
water in the well had, of course, a brackish taste. This woody
deposit was about at the base of the drift."

In the survey of Kankakee and Iroquois counties, the late
Prof. Frank H. Bradley found conclusive evidence of the exist-
ence of an ancient channel which he supposed to have been a
western outlet for the waters of Lake Michigan, and I quote
the following description of it from his report, Geol. Survey of
111., Vol. IV, page 229, et seq: "The depth of this channel in
its northern part is unknown; but its western bank is seen on
the Kankakee, just above Momence, wrhere the rock suddenly
breaks off, and probes forced to considerable depths found no
solid bottom. These facts were ascertained in 1867, by Col.
James Worrall, then of the Illinois River Survey, now of Har-
risburg. Pa., who also informs me that the same 'shoulder' of
rock is found on the Calumet, nearly due north from Momence.
In this part of its course, passing through very solid rocks, the
channel is rather narrow, rock having been found upon its east
side and south of the Kankakee, within seven miles of Mo-

12 DRIFT DEPOSITS OF ILLINOIS.

mence; the exact location of its eastern bank is unknown.
From this point the course of the channel is not certain; but
it proba.bly keeps near the State line until it nearly or quite
reaches the valley of the Iroquois, then runs westerly to the
valley of Spring creek, having a depth of one hundred and
sixty feet near Sheldon (as reported by H. S. Wing, Esq., of
Kankakee City,) and then turns south with a depth of two
hundred and sixty-eight feet between Onarga and Oilman, of
'over four hundred feet' between Onarga and Spring Creek Sta-
tion' and of 'over three hundred feet' between Paxton and Ean-
toul, as reported by John Faulds, Esq., of Catlin, Vermilion
county."

"As the western bank wras found at Chatsworth, Livingston
county, with its top eighty-eight feet and its bottom two hund-
red feet below the surface, thus giving a width of fifteen miles
or more, it is evident that the softer materials of the Devon-
ian, Sub-carboniferous, and Coal Measure shales and sandstones
have afforded less resistance to the denuding agent than the
solid Silurian limestones which confined it to less than seven
miles at Momence. Champaign and Urbana, in Champaign
county, are located over this old channel, and from one hund-
red and seventy-five to two hundred and twenty-five feet above
its floor, but are probably near its eastern border. Here and
at Chatsworth we find, among the drift-beds, a single layer of
old mucky soil, with leaves and trunks of trees. At Blooming-
ton, in McLean county, the channel is two hundred and fifty
feet deep, and the beds which fill it include two beds of old soil,
which I am inclined to accept as indications that this point is
near the middle of the old valley, or at least near its principal
channel."

Dr. Bannister, in his report on the northwestern counties of
the State, gives no artificial sections of the drift, but he gives
the following as an approximate section of this deposit in the
bluffs of Lake Michigan, near Lake Forest:

Ft, In.

Clay 10 to 14

Hand and clay intermingled 9 to 12

Clay 1 to 1 C

Sand 1

Clay 50

Maximum 78 6

DRIFT DEPOSITS OF ILLIXolS. 13

In regard to the boulders scattered through the drift clays of
this region, Dr. Bannister says: ".\ Tost of the large boulders in
this vicinity are of limestone; the masses of the primary or in-
irusive rocks are generally of comparatively small size, or when
of considerable size are but rarely met with."

So much must suffice our present purpose to illustrate the
prevailing character of the drift in the extreme northern por-
tion of the State, where we might expect to encounter the most
unmistakable evidence of glacial action, if these superficial de-
posits were really due to the action of land ice.

Coming south, within the northern boundary of the coal field,
we find an increased thickness of the drift deposits, and the
numerous artificial excavations that penetrate entirely through
them, afford the most satisfactory evidence of their general
character and extent.

In sinking the coal shaft at Wenona, in Marshall county, the
following drift beds were encountered:

Feet.

Soil and yellow clay 10

Blue clay (boulder clay) 46

Sand 10

Hard-pan 34

Red clay 3

Total 103

The red clay at the base of the drift at this locality was prob-
ably derived from the shales of the coal measures on which it

rests.

At the gas well near Clinton, in DcAYitt county, the following
beds of drift were encountered without quite reaching the bed
rock :

Feet.

Soil and yellow clay 15

Hard blue clay (boulder clay) • 30

Black mould with wood 2

Dry drab colored clay 8

Drift-wood and black mould 8

Drab colored clay 16

Drift-wood, etc 2

Drab colored clay 26

Hard-pan 12

Drab colored clay 4

Green copperas colored clay 10

Total... 133

14 DRIFT DEPOSITS OF ILLINOIS.

Dry sand and pebbles were thrown out upon the surface by
the pressure of the gas, indicating the presence of sand and
gravel beds beneath the green clay, the gravel beneath and the
clay above furnishing the necessary conditions for the reception
and retention of the gas, which was probably generated in the
bituminous shales of the coal measures beneath.

The well at the railroad station at Odell, in Livingston county,
passed through the following beds, according to the record as
reported, without reaching bed rock:

Ft. In.

Soil and yellow clay 9

Blue clay (boulder clay) 66

Gravel and sand 5

Blue clay 15

Gravel and sand 2

Blue clay • 8

Gravel 4

Blue clay 22 8

Gravel 4

Blue clay 2

Total 130 4

The coal shaft at Bloomington, in McLean county, was carried
down through the thickest deposit of superficial material pene-
trated by any coal shaft in this State. This extraordinary
thickness of drift fills the old channel, already mentioned, by
which the waters of the great lakes found an outlet into the
valley of the Illinois river, and thence, through the valley of
the Mississippi, into the Gulf of Mexico. The following is a copy
of the record of the superficial material in this shaft:

Feet.

Soil and brown clay 10

Blue clay 40

Gravelly hard pan (boulder bed) (iO

Black mucky soil 13

Clay hard-pan 89

Black soil 6

Blue clay 34

Quicksand

Total 254

The wood found in the mucky soil at the depth of one hun-
dred and ten feet proved to be in a remarkably fine state of
preservation, and belonged apparently to a species of cedar.
The quicksand at the bottom of the above section contained
the comminuted fragments of terrestrial arid fluviatile mollusca,

DRIFT DEPOSITS OF ILLINOIS ir,

of which only one specimen was obtained in a condition to be
determined, This specimen was submitted to the late Dr. St imp-
son, of Chicago, for examination, and was by him decided to be
a Helif-ina ocnilta.

One of the first attempts to shaft for coal in this State was
made at Coatslmrg. in Adams county, and this shaft afforded
the first evidence obtained of the existence of a bed of soil
beneath the boulder clay. The following is a copy of the record
of this -shaft :

Ft In.

boil and yellow clay 6

Clay with gravel and boulders 85

Black soil 2 6

Stratified clay 6

Tough blue clay 20

Total 119 6

This shaft was located on the high prairie that forms the
divide between the Illinois and Mississippi rivers.

At Decatur. in Macon county, two beds of soil were p,
through in sinking the coal shaft at that point, and the follow-
ing is a copy of their record as published by the local pr-

Ft. In.
Soil and clay 31

Sand, with two clay bands 11

Quicksand 2 6

Tough clay 4

Black soil 2 ,;

Sand -2

Clay ""/_' 3

Greenish sand .-. 6

Gravelly hard-pan H

Black soil 2

Quicksand 4

Gravelly clay 24

Quicksand 6 g

Total 109 6

At Pana. in Christian comity, about thirty miles south of
Decatnr. the two ancient soils of the above section were also
encountered in their shaft as is shown by the following record:

Soil and clay 11

Blue clay 4

Sand and gravel 12

Hard red clay 18

Black soil

Blue clay J7

Black soil 2 ,;

Blue clay i<»

To?al 127

16 DRIFT DEPOSITS OF ILLINOIS.

The following average section of the drift deposits in the
western part of Sangamon and eastern portion of the adjacent
county of Menard, was furnished by Mr. Joseph Mitchell, a
professional well-digger, and probably fairly represents the gen-
eral character of the drift in Central Illinois wrhere no unusual
amount of erosion had taken place. This section, however,
does not represent the full thickness of the drift, as the wells
were not continued quite down to the bed rock:

Ft. In.

No. 1. Soil and yellowish subsoil 5 to 10

No. 2. Gray sandy clay (loess) 6 to 8

No. 3. Mucky clay with wood, etc 2 6

No. 4. Bluish boulder clay lo to 15

No. 5. Soft blue clay 20 to 40

Maximum , 75 6

No. 3 of the foregoing section is not identical with either of
the old soils found at Blooming-ton, Decatur or Pana, but it
probably holds the same stratigraphical position as the "Forest
bed" of the Ohio reports, and the chocolate-colored clay be-
neath the loess at Quincy.

At Virginia, in Cass county, however, one of the older soils
was found, as shown by^ the following record of the shaft at
that locality:

Ft. In.

Soil and brown clay 9 6

Blue clay and hard-pan 57 6

Black soil 3

Hard-pan 46

Total 116

At the Palmer shaft, in Christian comity, the following record
was preserved of the drift beds passed through:

Soil and yellowish clay

Feet.
16

Hard boulder clay

22

Soft brown clay

7

Sand :

10

Gravel . ,

i

Boulder clay . .

4

Total...

60

Two boulder beds are reported in the foregoing section, the
first immediately below the yellow clay of the sub-soil, where

DRIFT DEPOSITS OF ILLINOIS. 17

it is usually found, and the other at the bottom o! the drift,
and directly above the bed rock. Nothing is said in the record
in regard to the size or number of the boulders contained in
either bed, but, if we may form any conclusion from the char-
acter of the fundamental bed of the drift deposits at all the
other localities given, we should be led to suspect that the
lower bed here might be more accurately described as a bed of
gravelly clay, rather than a bed containing boulders of any
considerable size.

The record of the coal shaft at Sidney, in Champaign county,
shows the following beds of drift occurring at that point:

Feet.

Sand and yellow clay 17

Boulder clay 18

Gray hard-pan 5

Yellow hard-pan 15

Coarse sand and gravel 5

Hard-pan 35

Total 95

In a boring with the diamond drill at Tuscola, in Douglas
county, the following divisions of drift material were encount-
ered:

Feet

Surface soil and yellow clay 20

Blue clay 5

Hard-pan 6

Blue clay 10

Hard-pan 7

Blue clay 9

Brown clay 5

Yellow clay 8

Blue clay 6

Blue and yellow clays 31

Blue clay 22

Gravelly blue clay 80

Blue clay 13

Sand... 6

Total 178

In sinking the coal shaft at Sandoval, on the O. & M. rail-
road, in Marion county, the following beds of drift material
were passed through according to their published record :

-2

18 DRIFT DEPOSITS OF ILLINOIS.

Soil and yellow clay

Ft.

11

In.

Sandy clay . . . .

4

6

Blue clay and gravel

20

Blue clay

78

Black soil

2

I

Blue sandy clay

6

6

Cemented gravel

1

Total 129

The bed of cemented gravel at the bottom of this section may
be a bed of ferruginous conglomerate belonging to the coal
measures, as such a bed is frequently encountered in the upper
part of that formation.

At Odin, four miles east of Sandoval, a similar bed of black
soil was encountered near the base of the drift, but no detailed
record of the overlying beds was preserved.

South of the 0. & M. railroad the drift deposits diminish in
thickness, and the following section, obtained from a boring for
coal at Lementon, in St. Cla'r county, will afford a general
idea of their average thickness and diversified character in
Southern Illinois:

Feet.

Soil : 3

Ye'low clay .- 14

Sand and gravel 1

Blue clay 20

Blue clay (soil?) 1

Blue and yellow clays 11

Bed and yellow sand 7 1

Total - ; 51

The foregoing sections afford a fair exhibit of the superficial
deposits of this State, all of which may be included in the gen-
eral term drift. They cover more tha.n two-thirds of its entire
area, including the central and northern portions of the State,
where these deposits attain their greatest development.

In the southern portion of the State, for a distance of fifty to
seventy-five miles north of the Ohio river, foreign material is
comparatively rare, and often absent altogether, arid when
found the boulders are of small size, seldom exceeding a few
inches in diameter.

DRIFT DEPOSITS OF ILLINOIS. 19

Specimens of native copper have been found in this portion of
the State, but their presence there may be due to human
agencies, as it is Avell known that copper wa\s an article of com-
merce among the primeval races of the Mississippi valley.

The conditions under which the drift deposits were accumu-
lated, and the agencies employed in their deposition, are still
unsettled questions, and the complex character of the phenomena
presented affords a wide field for speculation.

It has been generally conceded that a colder climate than that
of the present time prevailed over the northern temperate zone
when the boulder clays were deposited, and that ice was an im-
portant factor in the transportation of the foreign material
contained therein.

Two rival theories, known respectively as the "glacial" and
the ''ice berg" theories, have been advanced to explain the
origin of the drift, both of which have found able advocates to
urge their respective claims. The latter theory attributes the
accumulation of the drift and the foreign materials occurring
therein to floating ice and water currents during a period of
submergence, when the entire surface over which the drift extends
was beneath the water.

The ''glacial theory," on the other hand, attributes the ac-
cumulation of the boulder clays to the action of land ice, and
is based upon the assumed conditions of an arctic climate, and
a vast continental "glacier" or "ice cap," that was supposed
to have covered all the North American continent north of the
fortieth parallel of latitude.

Prof. Dana, in his Manual of Geology, 2d ed., page 544, gives
the following as the conditions supposed to prevail over the
northern portion of the continent during the ''glacial period":

"During a glacial epoch of the kind here supposed, the whole
northern portion of the continent down to the southern limit of
the Drift, would have been covered by a vast and almost unin-
terrupted glacier. This is now the case in North America with
the return of nearly every winter. But the depth, instead of
being as now, but a few feet, and that mostly of snow, must
have been, judging from the height on the hills to which the
striie extend, at least 4,000 to 5,000 feet, and the material, as
in all such thick accumulations, would have been ice, and above

20 DRIFT DEPOSITS OF ILLINOIS.

this there may have been other hundreds of feet of snow.
Glaciers of so vast extent and thickness, would have moved
downward wherever the conditions would permit, like the glaciers
of the Alps, and all the more readily for their enormous weight."

A glacier is usually defined as "an immense mass of ice, or
snow and ice, moving slowly down mountain slopes or valleys,"
and it is probable that the earliest advocates of glacial theory
in this country formed their conclusions mainly from an exami-
nation of the phenomena presented in New England, and other
mountainous regions, where the conditions necessary for the
formation of typical glaciers were prevalent, but as such condi-
tions were not found in the broad plains of the northwest, the
"ice sheet" or "ice cap" was substituted for the glacier, to ex-
plain the occurrence of foreign material in the drift deposits of
the northwest.

The glacial theory requires for its support, a supposititious
elevation of the surface, to the extent of several thousand feet,
of all that portion of the continent over which the drift is dis-
tributed. This was necessary in order to obtain the conditions
of an arctic climate in a temperate zone, a supposition with no
evidence to sustain it except what is afforded by the so-called
glacial phenomena.

As has been clearly shown by the preceding sections of the
drift deposits of Illinois, the boulder clays invariably overlie
an old soil, which covers such a wide area as to justify the con-
clusion that it was originally spread over the whole surface of
the State, and it seems highly improbable that a vast ice sheet,
of enormous thickness, could push its way over a nearly level
surface, and leave the soil intact beneath. Moreover, wherever
a good section of the drift clays, overlying the black soil, is
well exposed, the evidences of a more or less distinct stratifica-
tion is observable, a fact which does not accord with the "gla-
cial theory," but indicates clearly that water was an active
agent in their accumulation.

Foreign boulders are comparatively -rare in the central portion
of the State, except in the vicinity of the old valleys, where they
are more abundant than elsewhere, though seldom exceeding a
diameter of two feet, and in the extreme southern portion of
the State, those exceeding a few inches in diameter are seldom

DRIFT DEPOSITS OF ILLINOIS. 21

found. This is precisely what we might anticipate if they were
trail sported by floating ice, whereas if their occurrence was due
to the southward movement of land ice, they should be equally
or more abundant at the southern extremity of the ice sheet
than elsewhere.

Dr. Drake, of Cincinnati, in an essay published in the Trans-
actions of the American Philosophical Society, in 1825, ad-
vanced the theory ';that the boulders of foreign material in
Ohio, with the clavs in which thev were imbedded, were brought

«/ «/

from the north by floating ice during a period of submergence:"
and Sir Charles Lyell, on his first visit to America, adopted a
similar view, and explained the drift phenomena observed by
him in Canada, as the probable result of floating ice, loaded
with the rocks and detritus of the north.

Prof. Dawson, of McGill College, in his Acadian Geology, ad-
vocates a similar theory in explanation of the drift phenomena
observed by him in Nova Scotia. In discussing the probable
origin of the drift, on page 64 of the volume above cited, the
author says: "Let us suppose then, the surface of the laud,
while its projecting rocks were still uncovered by surface de-
posits, exposed for many successive centuries to the action of
alternate frosts and thaws, the whole of the untraveled drift
might have been accumulated on its surface. Let it then be
submerged until its hill-tops should become islands, or reefs of
rocks, in a sea loaded in winter and spring with drift ice, floated
along by currents which, like the present Arctic current, would
set from X. E. to S. W., with various modifications, produced
by local causes. We have in these causes ample means for ac-
counting for the whole of the appearances, including the trav-
eled blocks, and the scratched and polished surfaces."

The enormous transporting power of floating ice is well known
to be fully adequate to explain the occurrences of boulders, and
any other foreign material occurring in the drift deposits, and
the low temperature prevailing in the high northern latitudes,
from which the foreign material in the drift, of the Mississippi
valley has come, furnishes the essential conditions for the break-
ing up of solid rocks, reducing the broken masses to the condi-
tion of boulders, and transporting and distributing them as far
as the drift deposits extend.

22 DRIFT DEPOSITS OF ILLINOIS.

The scratching and polishing of the hard rock surfaces be-
neath the drift, as well as the striation of some of the bould-
ers, may be readily explained by floating ice, with embedded
angular fragments of still harder material, that would act as
gravers upon whatever solid substances with which they were
brought in contact.

The "iceberg" theory requires the assumption of no extraor-
dinary conditions to explain the drift phenomena, and it is a
generally accepted principle in geological science that no resort
to extraordinary suppositions is justifiable, where phenomena
can be explained by the operation of well known causes.

The gradual change of level in the relations of land and water,
is a dynamical fact universally admitted, and a general sub-
mergence of the surface after the disappearance of the conti-
nental glacier, or ice sheet, is admitted by the advocates of the
glacial theory; and, if the date of this submergence should be
carried back to the period immediately following the formation
of the ancient surface soil, beneath the boulder drift, we obtain
the essential conditions required for the accumulation of the
succeeding deposits of the drift period.

From the facts presented in the foregoing pages, we may as-
sume that the drift period represents a vast epoch in geologi-
cal time, during which a considerable portion of the Mesozoic
formations were in process of deposition over such areas as
were still submerged beneath the ocean; and hence the term
Post Pliocene can only be applied to the latest formed of these
deposits, the loess, which contains the oldest fossil mammalia
hitherto found in the superficial deposits of Illinois.

The succession of events transpiring in the northwestern por-
tion of the United States during the drift epoch, we may assume
to be somewhat as follows: First, the gradual elevation of the
surface above the ocean level at the close of the carboniferous
period, followed by the extensive denudation of the palaeozoic
rocks, and the excavation of extensive valleys, which seems to
have been the prevailing condition in the region now under
consideration during the Triassic and Jurassic periods.

The next occurrence in the order of succeeding events was the
partial filling of the valleys with clay, sand and gravel, and
the formation of the lowest bed of ancient soil beneath the
boulder clay. This was followed by a partial or entire submer-

DRIFT DEPOSITS OF ILLINOIS. 23

gence of the surface, and the accumulation of the sands, clays,
etc., that underlie the soil which occurs immediately beneath
the boulder clays.

Then the surface was elevated and the marshy swamp soil
under these clays was formed. A second submergence then fol-
lowed and through the agencies of water currents and ice-floes,
the boulder clays were deposited.

This was followed by a partial elevation of the surface and
the prevalence of lacustrine conditions, resulting in the deposit
jof the loess, while the adjacent dry land was inhabited by now
extinct forms of mammalia, associated with some of those still
existing in the same region. This was followed by the final
emergence of the whole area, and the commencement of the ex-
isting order of things.

The mammoth and mastodon were certainly coeval with spe-
cies of mammalia still existing in the Mississippi valley. This
fact has been clearly established by the collection of fossils made
by Mr. Me A dams from the loess, and by the fossil bones found
between Illiopolis and Niantic, near the east line of Sangamon
county. At this locality beneath a black mucky surface soil
only four feet in depth, the remains of a mastodon consisting
of the jaws with the teeth intact, both tusks, and several of the
large bones were found associated with bones of the buffalo,
elk and deer, all embedded together in a bed of quicksand that
had probably once formed the bottom of a pool of water to
which these animals resorted, and in which they perished. The
writer was present during the disinterment of these remains,
and some of the small bones of the mastodon and all those of
the smaller animals except the antlers of the elk are now pre-
served in the cases of the State Museum of Natural History.

No well authenticated discovery of the remains of mammalia
in this State in beds older than the loess or modified drift, has
come to the knowledge of the writer, and in every case where
such finds have been reported, investigation has shown that
they were obtained from beds more recent than the boulder
clays. Isolated bones and teeth are often obtained from the
alluvial banks of the streams, but more frequently they occur
in the black peaty soil or subsoil of the marshes, in which they
seem to be better preserved than when buried elsewhere.

24 DRIFT DEPOSITS OF ILLINOIS.

In the early part of our investigations in Illinois and Iowa,
the writer was inclined to accept the "glacial theory," as a prob-
able explanation of the conditions under which the boulder clays
were deposited, mainly in deference to the ability of its able
advocates, but later and more widely extended observation have
compelled its rejection as a reasonable or necessary explanation
of the phenomena presented, after a careful study of the super-
ficial deposits of this State.

When the advocates of the "ice cap" theory are able to pre-
sent some tangible evidence of the former elevation of the
northern portion of the American continent to the height of
several thousand feet above its present level, independent of
drift phenomena, or can point to some other plausible fact
going to show the prevalence of arctic conditions at a former
period over the temperate regions of North America, that theory
may be generally accepted, but until then, it is but fair to
assume that diverse opinions will prevail in regard to the
agencies by which the drift deposits of the Mississippi valley
were deposited.

It has seemed probable to the writer that many of the advo-
cates of the "ice cap" theory became converts to the theory
before commencing field investigation, and their researches were
consequently devoted to obtaining such facts as were believed
to have a favorable bearing upon the accepted theory. If they
have gone into the investigation of the drift phenomena of the
Mississippi valley entirely free from all preconceived ideas as to
its origin, it is a question whether either "glaciers" or an "ice
cap" would have been suggested as the most probable theory to
explain the phenomena of the drift, as it is distributed over the
vast plains of the northwest.

ECONOMICAL GEOLOGY. 25

CHAPTER II.

ECONOMICAL GEOLOGY.

COAL.

Since the publication of Vol. VII, of these reports, numerous
experiments have been made for the development of our coal
resources, the great majority of which have proved successful.
Among the most notable failures were those made at Tuscola
in Douglas, and Sidney in Champaign counti< -

Tuscola is situated some forty miles or more within the east-
ern border of the coal field, and also within the region supposed
to be underlaid by the upper coal measures, but, a boring made
there with the diamond drill to the depth of 792 feet, failed to
reveal the presence of coal, or any clearly defined strata be-
longing to the coal measures.

The drift deposits were found to be 186 feet thick at the point
where the boring was made, and if beds belonging to the coal
measures were originally deposited there, they were removed by
erosion at the commencement of the drift period, and the first
layers of bed-rock encountered by the drill appeared to be of
Lower Carboniferous age. At the depth of 645 feet a white
crystalline limestone containing Favosites was encountered,
which undoubtedly belongs to the Devonian or Upper Silurian
formations.

The oblique fracture of the core taken from this boring, showed
that the limestones passed through, dip at an angle of about
20°, which would give an exaggerated thickness to the beds as
reported, and shows that this boring is on, or very near the
center of the great anticlinal axis, which crosses northern Illi-
nois diagonally through the counties of Ogle and LaSalle, but
— o

26 ECONOMICAL GEOLOGY.

is hidden in its southeastern extension by the superincumbent
deposits of drift material. The following is a copy of the record
of this boring:

Ft. In.

1. Superficial deposits 186

2. Sandy shale 7

3. Sandstone 14

4. Green shale 20 7

5. Hard rock 4

6. Sandstone 46 1

7. Conglomerate 6 6

8. Sandstone with blue bands 14

9. Shale , H8 1

10. Soapstone (clay shale) 15

11. Sandstone 20

12. Sandy shale 10

13. Clayshale ." 42 6

14. Hard rock 6

15. Clayshale 9

16. Slate and shale 101 6

17. Blackshale 12 6

18. Limestone 140

19. White sandstone 20

Total depth 792 9

There is probably a considerable area along the line of the
above mentioned axis extending through the counties of Livings-
ton, Ford, Champaign and Douglas, that is colored as coal
measures on the map, where no valuable deposit of coal will be
found, such deposits having been removed by erosion if they
formerly existed over this axis as seems probable, but the
boundaries and extent of this barren area, can only be deter-
mined by the drill, or artificial excavations, as there are no
natural outcrops that will help to define its extent. There are
hundreds of square miles in this portion of the state, where
there are no natural exposures of the bed rock, and consequently
no definite knowledge in regard to the character of the under-
lying formations can be obtained by surface explorations, the
banks of the water courses revealing nothing but the upper
portion of the drift deposits.

Sidney in Champaign county, is about fifteen miles north, and
twelve miles east of Tuscola, and is probably on the eastern
side of the axis. In the published record of the boring there,
four coal seams were reported in a total depth of 256 feet, the
lower seam six feet in thickness, and the others ten, twenty and

ECONOMICAL GEOLOGY. 27

twelve inches respectively. This boring was made with an ordi-
nary drill, and on sinking a shaft it was found that the six foot
seam of coal reported in the boring, proved to be mainly a
bituminous shale.

If the Diamond drill had been used the expense of sinking a
shaft might have been avoided. The following record of this
boring was furnished and sworn to by Mr. E. Bobbins, the con-
tractor in charge of the work :

Ft. in.

1. Soil

2. Yellow clay

a Blue clay

18

4. Gray hardpan

5

5. Yellow hardpan

6. Coarse sand and gravel

5

7. Hardpan

8. Clay shale

„

9. CoaL

0

10. Clay shale

27

11. Coal

1

12. Shale

85

13. Coal

1

14, Limestone

16

15. Sandstone

4

16. Hard shale

2

17. Coal

6

Total depth.

256~

10

At Urbana and Champaign, borings have been made for coal
and favorable results reported, but all attemps to cany a shaft
down through the water-bearing sand and gravel beds of the
drift, have hitherto been unsuccessful.

The following beds of drift were encountered in attempting to
sink a coal shaft at Champaign, the details of which were pub-
lished in the report of Prof. Frank H. Bradley on the geology
of this county in Vol. IV. page 272 of these reports.

Feet.

1. Soil, clay and quicksand 17

2. Red and blue clay 73

3. Peaty soil

4. Quicksand 9

5. Soft yellow clay 9

6. Sand

7. YeUow clay ?

8. Quicksand and gravel 59

Total ~~

28 ECONOMICAL GEOLOGY.

In discussing the character of the drift deposits of this county
Prof. Bradley says: "The purity of the white water-bearing
quicksand which underlies the drift calls to mind the character
of the St. Peters sandstone at its outcrop in LaSalle county,
in which region it supplies several large artesian wells. The
southern continuation of the anticlinal axis which brings this
rock to the surface at that point, would pass not far from
Champaign; and it is altogether probable that the aforesaid
quicksand is really a part of the disintegrated outcrop of that
bed distributed over the bottom of the ancient channel* which
must have exposed it at some point in this region."

How far south this axis extends is a point as yet undeter-
mined, and its effect upon the productive coal measures in the
counties lying to the southeast of Douglas can only be deter-
mined by the drill, or the more expensive method of shafting.
If it extends to the Wabash river it would cross that stream in
the vicinity of Vincennes.

The record of the following borings in Livingston county were
furnished by D. E. Morgan, Esq., of Strawn.

Boring at the lumber yard in Strawn by H. Clarke.

No. Ft. In.

1. Soil 3

2. Gravel 1

3. Yellow clay 3

4. Blue clay 17

5. Sand and gravel with water 10

6. Light brown clay 20

7. Hard pan 2

8. Coarse gravel 8

9. Brown clay 14

10. Blue clay 9 6

11. Sandstone 8

12. Clay shale 13

13. Coal 2 6

14. Fireclay 3 6

Total depth 114 6

ii

Another boring near the section house west of the creek gave
the following result:

No. Ft. In.

1. Soil 3

2. Gravel 2

* For further remarks on this ancient channel the reader is referred to the preced-
ing chapter, page 11, and also to page 273 of vol. iv, of these reports.

ECONOMICAL GEOLOGY. 29

Ft. In.

3. Yellow clay 7

4. Gravel with water 2

5. Blue clay 7 6

6. Brown clay 17

7. Sand with water 3 6

8. Brown clay 8

9. Coarse gravel 2

10. Brown clay and sand 8

11. Sandstone and clay 4

12. Limestone (boulder) 0 3

13. Hard brown clay 12

14. Soft blue clay 2

15. Hard blue clay shale 25

16. Sandstone and shale 11

17. Dark clay shale 8

18. Coal -2 9

19. Fire clay 2 3

20. Clay shale 2

Total depth 129 3

A boring- at Cullom near the eastern line of the county made
by Mr. Bennett Reeder for the Livingston county Coal Pros-
pecting Company gave the following result:

No. Ft. In.

L

Soil

1

1

2.

Yellow clay

8

3.

Blue clay

32

1

4.

Sand

1

5.

Blue clay

24

l'..

Solid gray silt

12

7.

Blue hard pan

4

S.

Sand

0

a

ft,

Blue hardpan :

4

9

10.

Brown hardpan

(5

11.

Sand

0

6

12.

Brown hardpan

2

13.

Hardpan and silt

2

14.

Sand

0

6

15.

Hard silt

3

1

It'..

Hardpan.

5

17.

Clay

0

1

IS.

Hardpan

3

19.

Hardpan and gravel

2

20.

Brown hardpan very hard

53

21.

Bed clay

5

22.

Clay shale

19

23.

Coal ,

3

11

24.

Fire clay

4

Total depth 197 11

30 ECONOMICAL GEOLOGY.

The boring at^Strawn in the south eastern part of the county
failed to find a workable seam of coal, as shown by the follow-
ing copy of the record. The boring was made by Mr. Bennett
Eeeder :

No.

Ft. ]

1.

Soil

2

2.

Sand and clay

6

3.

Gray hardpan

2

4.

Blue hardpan

9

5.

Sand

0

8

C.

Blue hardpan ,

17

10

7.

Sand and gravel with water

7

6

8.

Blue hardpan

17

9.

Brown hardpan

16

10.

Sand and gravel ,

1

11.

Brown hardpan ,

3

12.

Sandy shale and sandstone ,

23

13.

Clay shale

12

14.

Sandy shale ,

6

15.

Pink shale ,

29

16.

Blue shale ,

10

17.

Sandstone hard and soft

17

18.

Clay shale with iron pyrites

8

19.

Sandy shale

20

20.

Dark clay shale

44

7

21.

Coal

1

2

22.

Bluish gray clay shale

7

23.

Eeddish brown clay shale

5

24.

Sandstone

23

3

25.

Sandy shale

12

26.

Bluish gray clay shale ,

2

Total depth 302

The boring at Saunemin in 1882 opposite the hotel, was not
carried deep enough to reach the workable coal, wrhich at that
point is 373 feet below the surface, while the boring was only
carried to the depth of 250 feet. There is probably but one
workable coal in the eastern portion of the county, which is
No. 2 of the general section. It is the equivalent of the lowest
seam in the shafts in LaSalle county, and is the one mainly
worked in Grundy county, and the southwestern portion of Will
and the northwestern township in Kankakee counties.

A boring made at Forest since the foregoing pages were
written, the details of which were furnished by Carmon Bros.,
found a coal seam, probably No. 2 of the general section, at a
depth of about 214 feet below the surface. The following details
were furnished by the parties above named:

ECONOMICAL GEOLOGY. 31

Ft. In.

Drifts clays, etc HO

Sandstone (boulder?) 1

Coal 0 10

Shale 3 6

Coal 0 10

Clay shale 98

Bituminous shale 0 g

Coal 3 2

Total depth 217 10

A boring made in Livingston county by Mr. B. Reeder, at Saune-
min reached a three foot six inch coal seam, probably No. 2 of
the general section, at a depth of 373 feet, 3 inches.

The following record of the Saunemin boring was furnished
by the Hon. Charles Ridgely of Springfield:

No- Ft. In.

1. Black soil 1 6

2. Yellow clay 10 6

3. Blue clay 4

4. Sand and gravel 3

5. Blue clay 14

6. Sand 2

7. Blue clay 9

8. Gravelly clay 2

9. Blue clay 54 g

10. Sand 4

11. Blue hardpan 28 6

12. Brown hardpan 3

13. Blue hardpan 26

14. Sandstone 13 g

15. Sandy clay 9

16. Sand and gravel with water 1

17. Clay shale 54 g

18. Alternating sandy and clay shales 6

19. Clay shale 2

20. Coal slate 1 g

21. Fire clay 2

22. Clay shale 78 g

23. Alternations of sandy and clay shales 6

24. Sandy shale : 8

25. Clay shale 2

26. Limestone 3

27. Sandy shale 3 g

28. Hard standstone 1 3

29. Sandy shale 3

30. Clay shale 13

31. Coal, No. 2 3 «

Total depth 373 3

If Nos. 15 and 16 of this boring are sand, clay and gravel, as
reported, underlying sandstone, it must be located on the

32 ECONOMICAL GEOLOGY.

border of one of the ancient valleys which are by no means un-
common beneath the drift, and the sandstone, No. 14, formed a
projecting ledge, from beneath which the strata had been removed
by the denuding agencies of the drift period, and replaced by
drift deposits. The drift is here one hundred and sixty feet in
thickness, and forms twelve distinct beds between the surface
soil and the sandstone.

The thickness of the coal and the character of the roof, leads
to the conclusion that the coal found here is No. 2 of the gen-
eral section, which is the lowest workable bed developed on the
north-eastern borders of the coal area.

Mr. T. S. Cummins of Gardner, who has been engaged in pros-
pecting for coal in the northeastern portion of the Illinois coal
field, has very kindly furnished me with the following short
account as the result of his observations in that portion of
the coal area:

"GARDNER, ILL., Jan. 12, 1885.
Prof. A. H. Worthen:

•'DEAR SIR: — I have read with interest your Economical Geol-
ogy of the State, especially that part of it relating to the county
in which I reside, and where it has been my privilege to do a
great deal of prospecting for coal, and boring for water, from
which I have gleaned facts which may be of use to you in de-
termining where the seam of coal in the Wilson shaft belongs,
which I believe to be identical with that found on the lower
Au Sable in Sec. 19. The principal characteristic of this seam
is its black shale covering. It overlies the main seam, and is
separated from it by sandstone and argillaceous shales aggre-
gating 70 to 80 feet in thickness, except near the outcrop
to the north and east, where the rocks between get thinner, and
the seams of coal come closer together. I have bored through
both seams south and west of the Wilson shaft, in South Grove
township, Livingston county, on the farms of Messrs. Clover,
Eldred and Pratt. The drift in that neighborhood was about
100 feet, then four feet of black slate, then the coal about 2
feet 6 inches. The other seam is 75 feet lower and 3 feet thick.
I have traced it from this point to within a half mile of Brace-
ville, where it is found in a well south of the old Augustine
shaft at a depth of 48 feet. I also found it on the south line of

ECONOMICAL GEOLOGY. 33

Braceville township, sec. 35. I found only 14 inches af coal at
this point at a depth of 65 feet. At the same point we got 3
feet 4 inches of coal at a depth of 146 feet. On sec. 19 in Essex
township, Kankakee county, north and east of the Wilson shaft,
the upper seam is found at a depth between forty and fifty feet.
This is its eastern boundary, and as the strata rise rapidly to
the eastward, both seams crop out within a short distance from
each other. The upper seam is best developed on sections 13,
24 and 25 in Greenfield township. On sec. 25, and on the farm
of Mr. Savage a little southwest of the Wilson shaft, the depth
is 106 feet; at the shaft on sec. 24, 80 feet; on 13 near the
center, 80 feet, and north about 80 rods from the east line of
the township, 69 feet, and on sec. 12 only between 40 and 50
feet. I have found it as far north as sec. 4, Felix township,
and the main seam below it, and so you will see that although
it is not a general deposit, it is distinct from the main coal and
belongs above it, as I have demonstrated.
Hoping this information may be of some use to you, I remain,

Respectfully yours,

T. S. CUMMINS."

The upper coal described by Mr. Cummins, is no doubt identi-
cal with that which outcrops on Waupecan creek in Grundy
county, and was referred to No. 3 of the Illinois section. Owing
to the irregularity in the development of coal seams on the
northern and northeastern borders of the coal field, the exact
position to which this seam should be assigned is somewhat
problematical, and it may represent a higher coal than No. 3,
and the character of its roof and its distance from the lower
seam, which evidently increases away from the border of the
field, render its identity with coal No. 5 of the LaSalle section
not improbable.

The boring at Clinton, made with the diamond drill, probably
penetrated to the ba,se of the coal measures, and passed through
352 feet of drift, showing that Clinton is located above one of
the ancient valleys, by which the surface of the state was in-
tersected anterior to the accumulation of drift material. The
following is a detailed copy of the record of this boring:

-4

34 ECONOMICAL GEOLOGY.

No. Ft.

1. Surface soil 5

2. Quicksand 15

3. Sand with gravel and boulders 17

4. Sand and clay mixed 53

5. Hardpan 12

6. Gravel 1

7. Hardpan 4

8. Clay and sand 4

9. Gravel and clay 7

10. Hardpan 3

11. Clay and sand 7

12. Clay and gravel 14

13. Clay 4

14. Hardpan <>

15. Clay and gravel 8

16. Quicksand 5

17. Sand and gravel 2

18. Coarse gravel 2

19. Clay «

20. Gravelly hardpan 25

21. Quicksand 6

22. Sand and clay 7

23. Gravel 9

24. Sand 11

25. Gravel 9

26. Sani 9

27. Quicksand and gravel 101

Total depth of drift 352

This is probably the same valley described in the foregoing
chapter, which was traced by Prof. Bradley into Champaign
county from whence its course was apparently west through
DeWitt, and thence northwardly through McLean county where
it was again penetrated in the Blooniington coal shafts.

The following strata of coal measure rocks were passed
through in the Clinton boring.

No. Ft. In.

1. Black slate 1

2. Fire clay 3

3. Limestone 19

4. Fire clay 1

5. Gray shale 1

6. Bed and gray shale 10

7. Gray shale 2

8. Sandstone 36

9. Gray sha'.e ., 32

Dark shale 6

10. Gray shale 5

11. Coal 2 9

12. Coal and slate 0 9

ECONOMICAL GEOLOGY. 35

Ft. In.

13.

Fire clay

7 3

14.

Limestone

22

15.

Sandstone

6

1C.

Gray clay shale

11

17.

Sandstone

11

18.

Grav shale

8

19.

Black slate and coal

3

20.

Limestone

7

21.

Sandstone

19

±!.

Gray shale

10

23.

Black slate

3

M,

Black slate and coal

4

25.

Gray shale

15

20.

Sandstone

50

27.

Gray shale

14

28.

Black slate

2

29.

Grav shale

5

30.

Sandstone -.

23

31.

Gray shale

21

32.

Black slate

3

33.

Coal

1

34.

Black slate and trace of coal

2

35.

Gray clay shale

3

36.

Coal

1

37.

Black slate and trace of coal

3

38.

Gray shale ,

16

39.

Hard impure limestone

1

40,

Hard sandstone

3

41.

Gray shale

5

42.

Black slate

8

43.

Sandstone

10

44.

Gray shale

3

45.

Black slate

2

46.

Gray shale

8

47.

Sandy shale

11

48.

Gray shale

9

49.

Hard limestone

1

50.

Hard sandstone

2

51.

Dark shale

3

52.

Gray shale

3

53.

Sandy shale

3

54.

Sandstone

6

55.

Black slate with trace of coal

2

56.

Gray shale

82

57.

Coal

1

58.

Gray shale

10

59.

Sandstone and shale

25

Thickness of coal measures

587 9

Total depth of boring

942

Another boring made previous to the one given above, located
just north of the town, and carried to the depth of 539 feet,
enconnteml only 270 feet of drift, showing that this deposit

36 ECONOMICAL GEOLOGY.

had increased in thickness about 70 feet in a distance of about
half a mile, the increased depth being in a southerly direction.
This would indicate that Clinton is located near the northern
slope of this ancient valley.

I am inclined to regard the 2 feet 9 inches coal reported in
this boring (No. 11) as probably the equivalent of the upper
workable seam in the Bloomington shaft, and also of that in
the shafts at Lincoln, Mt. Pulaski, and Decatur, and if so, it
is much thinner at Clinton than at the points above named.
Nos. 33 to 37 inclusive, represent a lower seam, that may be
equivalent to Nos. 2 or 3 of the general section, and No. 57
may be regarded as No. 1.

After the publication of Vol. VII, the proprietors of the coal
shaft at Mattoou put down a boring with the diamond drill to
the depth of 203 feet, which probably reached the bottom of
the coal measures.

For a detailed report of this boring, I am indebted to Walton
Rutledge, Esq. Commencing below the coal in the shaft, which
has been referred to coal seam No. 2 of the general section, the
details of the boring are as follows:

Ft. In.

1. Fire clay 15

2. Gray shale 70

3. Black slate 1

4. Coal 1 8

5. Fireclay 3 4

6. Dark shale 4

7. Coal 0 4

8. Fireclay : 1 8

9. Light shale 12

10. Hard sand rock 4

11. Sandy shale 27

12. Dark shale 45

13. Black slate 9

14. Dark green shale 6

15. Limestone 8

Total thickness 203

This, added to the 800 feet of coal measures passed through
in the shaft, gives a total of about one thousand feet, and rep-
resents probably about three-fourths of the entire thickness of
the coal measures in this State. Nos. 4 and 7 of the above
record represent probably coal No. 1, which is often a double
seam, and the limestone at the bottom belongs to the Lower
Carboniferous formation.

ECONOMICAL GEOLOGY. 37

A shaft at Srnithboro, in Bond county, passed through two
of the main coal seams in a depth of 498 feet, and a boring
can led down from the bottom of the shaft reported another
st-am about forty-five feet below the lower seam in the shaft.
The following is a copy in detail of the strata passed through
in this shaft :

.)

Hardpan

60

1

Blue clav

10

4.

Hardpau

10

5.

Limestone

6

0.

Light colored .shale

12

7.

Sandstone

12

8.

Dark slatv ^hale

23

ft.

Very hard limestone

2

0

10.

Black slate

2

11.

Coal, No. 9

1

12.

Light yellow shale

30

13.

Dark shale

... 17

14.

Coal, No. 8

1

15.

Slate, "

1

i<;.

Coal, "

1

17.

Shale and slate

62

18.

Hard sandstone with salt water

.. 100

lit.

Red shale

8

20.

Clay shale

2

21.

Sandstone

16

22.

Shale ,

31

23.

Limestone alternatinglwith shale

12

24.

Shale, broken coal and fragments of sandstone ; horizon of coal No. 7

7

2.x

Brown flre clay

2

20.

Light shale

8

27.

Black slate ,

4

2>.

Limestone

4

Lit.

Hard calcareous shale

4

30.

Band of concretionary iron stone

1

31.

Coal. No. 6

5

4

32.

Fire clay

2

0

33.

Gray limfist.nn« ,. ... ,,-,,--,, ..... ........

9

34.

Dark shale ,

3

3-".

Fire clay

4

30.

Limestone

4

37.

Coal. No. 5

4

1

K.

Fire clay

2

Total depth 498 10

The band of concretionary iron stone in the roof of coal No.
r». varies in thickness from six to twelve inches, and if the
quantity was sufficient to justify its exploitation, it would be
valuable for the production of iron. No. 24 seems to represent

38 ECONOMICAL GEOLOGY.

the horizon of another coal, which had been broken up and re-
deposited along with the bituminous shale and sandstone with
which it was associated, find it probably represents the horizon
of coal No. 7 of the general section. Coal No. G is the seam
being worked here at this time, and it affords a product of fair
quality. A heavy flow of salt water issues from the white sand-
stone No. 18, which is here a hundred feet in thickness.

A boring at Greenville, the county seat of Bond county, re-
ported five and a half feet of coal at a depth of 488 feet from
the surface. At this point the drift was found to be 200 feet in
thickness, consisting largely of sand and gravel with so great
an amount of water percolating through it that the parties in-
terested were deterred from attempting to sink a shaft for the
present. For the following record of this boring I am indebted
to the Hon. J. P. Slade of Greenville:

Ft. In.

1. Surface clay and soil 10

2. Sand and clay 20-

3. Coarse sand 10

4. Gravel 20

5. Conglomerate 90

6. Clay and sand 20

7. Sand 8

8. Light colored clay and sand 8

9. Dark colored clay and sand 18

10. Gray limestone 5

11. Hard black slate 5

12. Light and dark shales 77

13. Sandstone and sandy shale !»9

14. Clay shale 17

15. Sandy shale , 5

16. Clay shale 27

17. Limestone 1

18. Clay shale 5

19. Limestone 9

20. Clay shale and green clay 10

21. Black fault 5

22. Clay and sandy shales 10

23. Limestone 3

24. Clay shale 4

25. Limestone 2

2C. Coal 5 G

27. Shale... 7

Total depth 500 6

It is probable the coal seam at the bottom of this boring is
No. 6, and the stratum numbered 21, which is described in the
record as a black fault, represents the horizon of coal No. 7.

ECONOMICAL GKOLOGY. 39

Greenville is undoubtedly located upon the line of one of the
ancient valleys that were excavated either at the commence-
ment of the drift period, or during the elevation of the surface
above the carboniferous sea beneath which the coal measure
rocks \\ere formed, and by comparing the boring at Greenville
with the shaft at Smithboro, we find the ancient valley attained
a depth of about one hundred feet more at Greenville than at
the latter point. A notable feature of the drift at Greenville, is
the great amount of sand and gravel which it contains, and
the small amount of clay. The 90 feet described as conglom-
erate by the men in charge of the boring, was probably a bed of
gravel, cemented either with ferruginous or calcareous material
such as may be frequently observed in surface outcrops of the
drift deposits.

The coal shaft at Sorento, in Bond county, at a depth of 373
feet, penetrated a coal seam 8 feet in thickness. For the fol-
lowing copy of the n-conl J am indebted to Mr. Walton Kut-
ledge the mine inspector of that district:

No. Ft

1. Soil and clay 17

2. Conglomerate 28

3. Clay shale 20

4. Limestone I

5. Clay shale 4

6. Light gray limestone 20

7. Light limestone and chert 8

X. Fin- clay j

9. Black slate

I", i 'lay shale w

11. Red shale

1 1'. ('.'•< >al "m"m j

13. Fire clay „

14. Brown shale ^

15. Light shale ,„

Iti. Clay sha!< •

17. Magnesian limestone

18. Clay shale '.'.'..'".'. 20

19. Brown shale

20. Light shale

NoTE.-The sections of drift reported in connection with the coal shafts and
borings given in this chapter, were mainly obtained after the preceding chapter was
written, and tend to confirm the position hitherto assume,! jn regard to the origin of
the drift beds, and demonstrate very clearly to the mind of the writer, that they are
not the accumulations of land ice, but are largely if not wholly due to aqueous agencies.
— A. H. \\ ,

40 ECONOMICAL GEOLOGY.

No. Ft.

21. Fire clay 8

22. Light shale 27

23. Light hard limestone 9

24. Fire clay and slate ' 1

25. Coal : 8

26. Fire clay and shale (dump) 20

Total depth 401

The boring made at Sorento previous to sinking the shaft
was carried to the depth of 612 feet without finding any other
seam of coal of practical value. The following beds were passed
through by the drill below the bottom of the shaft, as pub-
lished in the Greenville Sun:

No. Ft. 1

1

Light shale

20

'>

Clay shale

30

3

Hard limestone

4

\

Slate

20

">

Brown shale

18

(

Limestone

]

7

Sandy shale and sandstone

52

8

Coal blossom?

4

0

Hard yellow stone

4

in

Slate

23

11

Soft shale

as

211
Shaft 401

Total depth 612

Although SorentO and Smithboro are but a few miles apart
there is a marked change in the character of the beds encount-
ered in the two shafts at these points. At Smithboro three
seams of coal were found in a depth of 537% feet while at
Sorento a single seam only was encountered in a depth of 612
feet. Such sudden changes in the character of the strata are
not of common occurrence in the Illinois coal field, though they
have been rarely encountered at other localities.

Three coal shafts were commenced without a preliminary bor-
ing in Marion county, and all have been prosecuted to a suc-
cessful issue; one at Kinmundy, and the others at Odin and
Salem respectively. The shaft at Kinmundy, although the
deepest of the three, was the first completed, reaching the hori-
zon of coal No. 6 at the depth of 869 feet. The seam at this
point was found to be divided by a parting of shale and lime-
stone about seven feet in thickness, the upper division of the

ECONOMICAL GEOLOGY. 41

seam having a thickness of two feet two inches, and the lower
of four feet two inches of good coal, while at Odin it is a solid
seam of nearly seven feet in thickness.

The record of the Kinmundy shaft was very accurately kept
by the gentleman in charge of the work, and it is a very im-
portant one, as it gives more than two hundred feet of upper
coal measure strata not found at Odin or Sandoval. This is
in part due to the greater elevation of the surface at Kinmundy,
which according to the railroad level is 96 feet above Sandoval,
and in part to the absence of the heavy deposit of drift, which
was found both at Sandoval and Odin, and to the easterly dip
of the strata.

The following is a slightly condensed copy of the record of
the Kinmundy shaft.

No

Ft.

In.

1.

Soil and brown clay

12

2.

Sandstone and shale

134

5

3.

Pebbly limestone

1

4

4.

Black slate

9

7

5.

Coal, No. 15

1

2

6.

Fire clay

7

7.

Gray shale

19

7

8.

Black slate

11

9.

Coal, No. 14

1

f.

10.

Fire clay

2

11.

Shale

37

10

12.

Black slate

5

13.

Bituminous limestone

2

14.

Coal, No. 13

0

ti

15.

Limestone and black shale

6

16.

Coal

0

2

17.

Clay shale

5

6

18.

Gray and black shales with bands of limestone ,

51

19,

Black slate

1

6

20.

Coal, No. 12

1

21.

Fire clay

1

6

22.

Limestone

3

23.

Gray shale

15

9

24.

Black slate ,

3

25.

Coal, No. 11

0

2

26.

Fire clay

2

10

27.

Shale and sandstone

66

6

28.

Coal, No. 10

0

4

29.

Fire clay

4

30.

Limestone

3

31.

Shale

81

32.

Limestone (Shoal Creek) ,

9

10

33.

Black shale with 2 inch coal No. 9

2

34.

Pebbly fire clay

5

5

42 ECONOMICAL GEOLOGY.

Ft. ]

tn.

35.

Sandstone and shale

76

36.

Pebbly limestone

1

6

37.

Bituminous shale and & inch coal

2

6

38.

Fire clay

5

39.

Sandstone and shale

69

40.

Black shale

0

10

41.

Coal, No. 8

0

7

42.

Fire clay

2

43.

Limestone, sandstone and fire clay

8

6

44.

Blue shale

14

2

45.

Limestone

21

6

46.

Fire clay

2

47.

Green shale

1

6

48.

Pebbly 'limestone

6

49.

Sandstone and shale

84

2

50.

Coal, No. 7

2

51.

Fire clay

11

52.

Sandstone and shale

30

53.

Coal

2

2

54.

Black shale

3

55.

Hard dark gray limestone

4

56.

Coal

4

2

Total depth 859 7

The limestone and shale parting in the coal at Kinmundy, is
a feature that I have observed nowhere else in the state. It is
probably a local development only, and may wedge out in some
direction in a short distance. In whatever direction the coal
thickens ' as the work of exploitation progresses, it should be
followed, with the expectation that the two divisions will gradu-
ally approach each other by the thinning out of the stony
parting until they finally come together.

A boring to the depth of about 130 feet from the bottom of
the shaft, reported only one seam of coal about eighteen inches
thick about seventy feet below the main coal.

An analysis of two samples of coal from the Kinmundy shaft,
by Prof. Barrett of the University of Illinois, gave the following
result :

FIEST SAMPLE. SECOND SAMPLE.

Ash 12.54 Ash 13.13

Moisture 8.40 Moisture 8.32

Fixed carbon 48.04 Fixed carbon 48.66

Volatile matter ... 30.26 Volatile matter ... 30.03

99.24 100.04

Per cent, of sulphur in coal 2.85

Per cent, of sulphur in coke 0.97

ECONOMICAL GEOLOGY. 43

The following copy of the record of the Odin shaft will be of
interest for comparison:

1.

2.

3.

4.

5.

6.

7.

8.

9.
10.
11.
12,
13.
14.
15.
16.
17.
18.

20.
21.
22.
23.
24.
25.
26.
27.
28.
29.
30.
31.
32.
33.
34.
35.
36.
37.
38.
39.
40.

Nodular shale

1

3

Coal, No. 12

0

9

Shale and fire clay

39

Coal and black shale

3

10

Shale and fire clay

14

G

Coal, No. 11

0

7

Sandy shale and sandstone

20

Blue clay and flre clay

12

G

Calc. sandstone, fossiliferous

8

Blue shale

3

Coal (local)

0

2

Fire clay ,

0

G

Sandy shale

14

2

Coal, No. 10

0

7

Sandy and arg. shales

63

Limestone (Shoal Creek)

10

Black slate and 2 in. coal. No. 9

3

2

Fire clay ,

5

Sandstone and shale

56

6

Blue shale with limestone bands

11

10

Fire clay

5

Slate and limestone

8

Clay shale

10

Sandstone ,

, 63

Blue shale

28

Nodular black shale ,

7

Coal, No. 8

0

10

Fire clay

2

G

Sandstone and shale

117

Pebbly shale and flre clay ,

11

Limestone, partly hard

14

Blue shale

10

G

Coal (local)

1

4

Fire clay and shale

10

8

Coal, No. 7

3

2

Fire clay

4

Alternations of shale and limestone

26

Black shale

4

Coal, No. 6

7

Total depth ...................................................................... 701 4

The Kinmundy shaft is eleven miles north, and about twelve
miles east of Odin, and the subjoined condensed vertical section
of the coal measures encountered at these two points, placed
side by side for comparison, will serve to show the uniformity
of their development in this portion of the State.

44

ECONOMICAL GEOLOGY.

Odin Shaft.

Ft. In.
Shale 1 3

Shale, slate, etc 48

Shale, fire clay, etc 58

Shale, limestone, etc 72

Sandstone, shale, etc 196

Limestone, shale, eto 155

Limestone, shale and slate 34

Coal No. 6 . . ,

Kinmundy Shaft.

Ft. In.
Sandstone and shale 140

Shale and slate 38

Limestone, shale, eto 62

Shale, slate, etc 23

Shale, slate, etc 68

Shale, limestone, etc 88

Sandstone, shale, etc 160

Limestone, shale, etc 142

Limestone, shale and slate 41

Coal No. 6 . . 64

At Salem the shaft was sunk to the depth of 886 feet, and
the following details were furnished by Mr. R. S. Dingle who
was in charge of the work.

The drift deposits were found to be 126 feet thick with the
ancient soil in place about ten feet from the bed rock.

No,

Ft. ;

[n.

1.

Soil and subsoil

i

10

2.

Hardpan

3

3.

Yellow clay

9

4.

Yellow clay and sand

10

5.

Blue clay and gravel

50

6.

Brown clay with wood

30

7.

Blue clay, sand and wood

12

8.

Black soil

1

9.

Blue mud and sand

9

2

10.

Sandstone

0

6

11.

Clay shale

8

12.

Black limestone

1

10

13.

Coal

1

2

14.

Fire clay

1

7

15.

Conglomerate of lime and sand

4

7

1C.

Blue shale and slate

26

17.

Clay shale

17

18.

Sandy shale

10

19.

Dark blue shale

11

2

20.

Coal

0

5

21.

Fire clay

0

7

22.

Dark blue shale with sand partings

9

23.

Light blue limestone

7

8

24.

Fire clay

3

ECONOMICAL GEOLOGY. 45

No.

Ft.

In.

25.

Sandy shale

3

26.

Clay shale

8

27.

Coal

0

4

28.

Fire clay

0

10

29.

Sandstone and sandy shale

54

30.

Blue shale

7

31.

Gray shale

5

6

32.

Dark blue shale

5

4

33.

Gray limestone •

5

34.

Fire clay

2

3

35.

Sandstone

11

36.

Clay shale

14

9

37.

Bituminous shale

2

6

38.

Coal

0

9

39.

Fire clay

0

3

40.

Conglomerate of lime and sandstone

3

(i

41.

Sandstone and sandy shale

35

42.

Clay shale

22

43.

Light gray limestone

12

44.

Hard massive sandstone

8

45.

Sandy shale

21

46.

Clay shale

23

47.

Coal

0

4

48.

Fire clay

1

2

49.

Conglomerate lime and sandstone

7

50.

Shale and slate

25

4

51.

Limestone (Shoal Creek)

14

52.

Black slate

3

53.

Coal

0

2

54.

Fire clay

4

6

55.

Sandstone and sandy shale

61

6

56.

Blue shale

8

57.

Conglomerate of lime and sandstone

1

6

58.

Black slate

2

2

59.

Gray limestone

0

6

60.

Coal

0

1

61.

Fire clay

4

3

62.

Nodular clay shale

8

63.

Blue slate

1

64.

Coal

0

4

65.

Blue slate

1

8

66.

Hard sandy shale

10

4

67.

Dark blue slate

2

8

68.

Conglomerate of lime and sandstone

5

3

69.

Sandy shale and sandstone

16

3

70.

Shale and slate

31

71.

Brown limestone

0

2

72.

Clay shale and slate

6

4

73.

Limestone

1

74.

Blue slate

6

75.

Coal

1

4

76.

Fire clay

1

6

77.

Nodular shale (calcareous)

8

78.

Sandstone and sandy shale

33

9

79.

Blue shale

44

46 ECONOMICAL GEOLOGY.

No.

Ft.

In.

80.

Fire clay

1

5

81.

Conglomerate of lime and sandstone

3

82.

Fire clay

7

83.

Dark gray limestone

, 9

84.

Clay shale

19

6

85.

Coal

0

0

86.

Fire clay

3

6

87.

Limestone with clay partings

19

G

88.

Sandy shale

33

89.

Blue slate

0

4

90.

Coal

2

2

91.

Fire clay

0

10

92.

Black slate

2

2

93.

Gray limestone

2

94.

Black slate

1

6

95.

Coal

4

G

96.

Fire clay

4

3

Total thickness .................................................................. 899 3

The strata reported above seem to be about 13 feet more in
thickness than the depth of the shaft as measured after the
completion of the work.

A boring at Hillsboro, in Montgomery county, made by the
Chicago Diamond Drill Company, was carried to the depth of
769 feet, and penetrated through the lower coal measures, and
into the upper division of the Lower Carboniferous formation.
The following is a copy of this boring kindly furnished by Mr.
Geo. C. Bryce:

Ft. In.

1. Yellow clay, sand and pebbles ...................................................... 14

2. Hardpan .............. ................................................................. 23

3. Quicksand ............................................................................ 1

4. Hardpan ............................................................................... 16

5. Yellow clay ........... '. ............................................................... 7

6. Sand and gravel ...................................................................... 20

7. Blue clay .............................................................................. 26

8. Coarse sand and gravel .............................................................. 16 6

9. Limestone ............................................................................. 8

10. Clay shale ............................................................................. 52 6

11. Limestone (Shoal Creek) ............................................................. 8

12. Bituminous shale ..................................................................... 1 8

13. Coal, No. 9 ............................................................................ 0 8

14. Clay shale ............................................................................. 29 8

15. Sandy shale and sandstone .......................................................... 65

16. Fireclay. (Horizon of coal No. 8) .................................................. 8

17. Sandy shale ........................................................................... 24

18. Sandy slate ............................................................................ 78

19. Clay shale, upper part nodular ..................................................... 9

20. Hard limestone ....................................................................... 5 6

21. Clayshale .............................................................................. 11 6

22. Limestone ............................................................................. C

Kn )X()MICAL GEOLOGY. 47

No. Ft. In.

23.

Bituminous shah'

3

21.

Limestone

5

8

25.

Clay shale

7

1

26.

Hard limestone

7

6

27.

Bituminous shale

6

28.

Coal, No. 6

5

29.

Sandy sh^lo and sandstone

8

30.

Argillaceous limestone

, 11

31.

Clay shale

9

32.

Argillaceous limestone

10

33.

Slate with hard bands

19

34.

Sandy shale

33

3*.

Coal 1 foot, slate 6 in., coal 1 foot— No. 5

2

e

36.

Slate ,

2

6

37.

Sandstone

8

6

38.

Slate

33

39.

Sandstone ,

5

40.

Limestone

1

41.

Bituminous shale and coal

2

42.

Fire clay

8

43.

Bituminous shale and coal

2

44.

Fire clay

5

45.

Slate with clay bands

10

4ti.

Coal

1

47.

Fire clay

12

48.

Sandstone

8

49.

Fire clay

1

50.

Bituminous shale

1

51.

Sandstone

131

52.

Limestone

10

Total depth 769

The drift at Hillsboro was found to be 123% feet in thickness.
and contains some very clean beds of gravel near the bottom,
which outcrop at the base of the hill near the railroad depot.

The stratum, numbered 35, is probably coal No. 6, which
holds about its average position here below the Shoal Creek
limestone. Coal Xo. 8 belongs above the fire clay No. 16 of the
section, but no bituminous matter seems to have been brought
up from that horizon by the drill.

From an examination of the core taken from the bottom of
this boring, it was evident that it had penetrated the Chester
division of the Lower Carboniferous, the purple shale and argil-
laceous limestone of that formation, being readily recognized.
A portion and possibly the whole of the sandstone No. 51 of
the record, and the underlying limestone. No. 52, belong to
that horizon.

48 ECONOMICAL GEOLOGY.

Since the publication of Vol. VII, an air shaft was sunk at
Decatur, the details of which were furnished for publication by
Charles Hansel, Esq., resident engineer of the middle division of
the Wabash, St. Louis and Pacific Railway. It is published as
a correction of the boring made with a common drill before the
coal shaft was sunk, a copy of which was published in Vol. VII,
page 17 et seq. of these reports. The air shaft is located about
half a mile south-west of the coal shaft., near the bluffs of the
Sangamon river. The following is a copy in detail of the record
kept:

No

Ft. ]

[n.

1.

Soil and loamy clay

25

2.

Sand and water (flow of 400 gallons per minute)

30

3.

Blue clay

4

4.

Drift wood and soil

2

5.

Green sand

4

6.

Gray sand

6

7.

Hard blue clay

9

8.

Sand and gravel (five strata)

37

9.

Hardpan

23

10.

Sandstone

1

6

11.

Soft shale

6

12.

Gray and blue sandy shale

28

13.

Clay shale

15

14.

Blue slate

17

15.

Ferruginous fire clay

6

16.

Conglomerate limestone

7

17.

Brown slate

10

18.

Flint stone

2

6

18.

Black slate

1

19.

Flint rock

2

6

20.

Coal, No. 11

0

10

21.

Fire clay

8

22.

Blue sandy shale

10

23.

Flint stone

3

24.

Clay shale

5

25.

Sandy shale

21

26.

Black slate

2

6

27.

Coal, No. 10

1

28.

Fire clay

6

29.

Black shale and 1 inch of coal

8

1

30.

Fire clay

6

31.

Black shale

3

32.

Impure limestone

1

33.

Brown shale

8

34.

Sandstone

1

35.

Black slate

4

36.

Flint stone

11

37.

Black slate

12

38.

Fire clay

4

39.

Limestone (Shoal Creek)

10

40.

Black slate (coal No. 9)

2

41.

Fire clay

8

ECONOMICAL (JKOLOGY. 41)

Ft. I

11.

42.

Clay shale

13

BL

Sandstone

5

41.

Flint stone

2

45.

Blue slate

8

46.

Clay shale

39

47.

Blue sandstone

1

Black slate

3

49.

Coal, No. 8

1

4

50.

Fire clay

6

51.

Sandy shale

10

HL

Black shale

33

53.

Hard black slate

5

54.

Coal (local)

0

:;

55.

Fire clay

4

56.

Limestone

11

57.

Black shale

4

58.

Clay shale

2

59.

Coal (coal No. 7)

0

4

60.

Fire elay

2

61.

Conglomerate stone

3

62.

Gray and blue clay shale

14

63.

Black slate and % inch of coal

4

64.

Fire clay

4

65.

Sandstone

7

66.

Gray shale

6

67.

Black slate

2

68.

Coal (Coal No. 6)

I

4

69.

Clay shale, ( " ' ")

i)

6

TO.

Coal ( " " ")

, '2

1"

71.

Hard gray shale

8

72.

Limestone

2

6

73.

Bituminous shale and coal ,

0

6

74.

Fire clay

4

75.

Sandstone

17

7ti.

Clay shale

3

77.

Sandstone

13

78.

Dark clay shale

8

79.

Black slate

1

6

80.

Coal, No. 5

4

6

Total depth 528 6

No. 49 of the above record is the equivalent of No. 35 iu the
boring at Decatur, published in Vol. VII, page 18, and repre-
sents coal No. 8 of the general section. In the record of the
boring it is described as a six-foot seam of coal, but is really
a thin coal, overlaid by four or five feet of bituminous shale.
It ivquirt-s ,-i very close and careful inspection to distinguish
coal from bituminous shale in the pulverized material brought
to the surface in the sand pump from a boring with the com-
mon drill, and in the majority of the borings of that kind

made in this State, the reported results have- proved mislead-
— 0

50

ECONOMICAL GEOLOGY.

ing when a shaft has been sunk to the horizon of the coal re-
ported, entailing in many cases a heavy loss to the company
undertaking the work. With the diamond drill this uncertainty
is easily avoided.

The beds described as flint rock in the air shaft record, are
probably hard silicious limestones which are not uncommon in
the Illinois coal measures, while beds of true chert (miscalled
Hint) are of rare occurrence.

Two experiments for the developement of coal in Morgan
county, were undertaken shortly after the publication of Vol.
VII. Both extended to the bottom of the coal measures, and a
condensed copy of the two records is herewith given side by
side for comparison. The experiment made at Franklin was by
a shaft, and that at Waverly by boring.

Franklin.

No. Ft. In.

1. Drift clay 35

2. Sandstone 25

3. Coal 0 9

4. Fire clay shale etc 131

5. Limestone 7

6. Coal 4 C

7. Fire clay, shale, etc 85

8. Coal 1 2

9. Fire clay, shale, etc 40

10. Coal 2 (i

11. Fireclay t>

12. Limestone...

Waverly.

Ft. In.
Drift clay 25

Sandstone and slate ... . 17 (i

Coal 0

Fire clay, shale, etc 153

Limestone 6

Coal 1

Fire clay, shale, etc 141

Coal 3

Fire clay, shale 55

Coal 1

Fire clay 1

Limestone. . . ,

No. 6 probably the equivalent of the Springfield coal, No. 5
of the general section, while the lower seams Nos. 8 and 10
represent coals 1 and 2, and No. 12 the upper bed of the lower
carboniferous group.

About the same time a shaft was sunk at Mt. Pulaski in
Logan county and one about a mile; northeast of Lincoln in
the same county. Of the latter I have been unable to obtain
a record, and for that at Alt. Pulaski I am indebted to Mi-.
Beard of Springfield under whose supervision the work was
done :

i:n>\<>MI('AL (IKOLOCY. 51

No. Ft. In.

1. Drift clay and gravel (details not preserved) <»•_>

2. Sandy shalo 20

3. Limestone 1

4. Fire clay 1 6

•">. (.iray slate -_>d

ii. Sandy shale 40

7. Limestone ;>

8. Black shale 1

!». C'.-.al No. 8 1 o

H>. Fire clay 2

11. Clay shale 4

12. Gray shale (sandy) 60

13. Conglomerate limestone 15

14. Clay shale 2

1.-.. Black slate !

li;. Coal 6 inches, fire clay 6 inches 1

17. Black slate 10 inches, coal 4 inches 1 2

18. Fireclay o $

1'.'. Reddish shale 10

-andstone 30

21. Sandy clay shale 30

22. Black limestone g

23. Coal No. 5 4

24. Fire clay 4

Total depth 351 10

The Medora shaft is located on the west line of Macoupin
county, and readies the bottom of the coal measures. The fol-
lowing strata \vere passed through at that point.

No. Ft. In.

1. Black soil 4

2. Yellow clay 20

3. Blue clay 30

4. Drift gravel 20

5. Clay shale 10

6. Shale 4

7. Blue limestone 2

8. Black slate 3

9. Coal 0 5

1". Fire clay 4

11. Gray slate 5

12. Sandstone 5

13. Clay shale 5

14. Shale 5

15. Black slate 3

1C. Coal 1

17. Fire clay 4

18. Red clay shale 0 8

ly. Sandstone 8

20. Limestone 2

21. Nodular clay 5

22. Clay shale 5

23. Clod?... 1

52 ECONOMICAL GEOLOGY.

No.

Ft.

In.

24.

Limestone

6

25.

Clay shale

2

26.

Black slate

2

6

27.

Clay shale

6

28.

Light shale

9

6

29.

Blue fire clay

C

4

30.

Clay shale

2

10

31.

Sulphur band

0

8

32.

Fire clay

H

33.

Nodular clay

4

34.

Fire clay

14

7

35.

Sandstone

12

4

36.

Shale

50

2

37.

Gray shale

19

5

38.

Clay shale

6

6

:«».

Gray shale

7

6

40.

Black slate

1

4

41.

Sandy shale

6

4

42.

Gray shale

30

7

43.

Black slate

2

44.

Coal

X

45.

Fire clay

1

8

46.

Hard limestone

6

Total depth 351 4

No. 44 is the lowest seam developed in this portion of the
State, and is probably identical with that of the Roodhouse
shaft in Greene county, and the Alton coal of Madison county.
It varies in thickness from two to four feet, and has a good
roof of hard bituminous shale which at some points cont;iins
beautiful fossil shells, in wThich the calcareous matter is replaced
with bright yellowr pyrites of iron. The coal itself is also more
or less impregnated with the bi-sulphurate of iron.

A shaft at Elkville, in Jackson county, reports nine feet of
coal at the depth of 110 feet below the surface. The folio wing-
record of this shaft was furnished by Mr. Robert Winning, mine
inspector of that district:

No, Ft. In.

10

in

1

Drift clay and soil

33

'>

Sandstone

7

Clay shale

15

4

Black slate

1

5

Fire clay

2

o

Limestone

7

7

Dark blue slate

8

Coal

2

Fireclay

0

10.

Sandstone . . ,

4

ECONOMICAL <;i:<>LOGY. 53

Ft. In.

11. Dark slate ............................................................................. 4

12. Fire clay ............................................................................... 3 g

i:i. Coal ................................................................................... i 2

14. Fire clay .............................................................................. g 10

1"'. Limestone ............................................................................ 4

Hi. Blue slate .............................................................................. 2 1<>

17. Limestone ............................................................................. 4 4

18. Dark slate ............................................................................. ! 6

1!'. Black limestone .................................................................... 4

A>. Blat-k slate ............................................................................ 7

21. Clay shale ........................................................................... 0 9

±i. Coal .................................................................................... 9 2

To-al depth of shaft ............................................................ 129

This is probably the same coal that outcrops four miles north-
east of Ora. on Rattlesnake creek, which I have referred to the
horizon of coal No. 1 of the Illinois section. The reported thick-
ness of the seam in this shaft is greater than it has been found
elsewhere in the state, but it is usually a very irregularly
developed seam.

One of the most important developments of coal in Southern
Illinois within the past two years, is the opening up of the out-
rrops on Rattlesnake creek in Jackson county, referred to above.
near the renter of township 7 south. 3 west. This outcrop was
mentioned in the report on Jackson county. Vol. 3, page 74 of
these reports, but no attempt to work the seam, except in a
very limited way. was made until recently, for the want of
proper facilities for transportation. Since the construction of
what was formerly known as the St. Louis and Cairo Narrow
Gauge Railroad, now known as the Mobile and St. Louis Rail-
road. a tramway has been constructed two miles north of Ora,
extending from the above named railroad to the mines, a dis-
tance of about two miles.

This was done by Messrs. J. C. Bryden & Co., who have estab-
lished a plant on the outcrop of the seam, capable of furnishing
from three to four hundred tons of coal per day, with a mining
force of one hundred to one hundred and twenty-five men. The
M-am varies in thickness at the several outcrops in this town-
ship from four to seven feet, and is enclosed between two beds
of sandstone. Sometimes the upper sandstone rests directly on
the coal, and at other points is separated from it by a thin bed
of argillaceous shale.

54 ECONOMICAL GEOLOGY.

The coal is quite free from the bi-sulphuret of iron, yields a
white ash, and is said to leave no clinker when used for do-
mestic purposes. On sec. 22, its position is rather above the
drainage level of some of the small streams, and consequently
has been cut out by erosive agencies in the creek valleys.

This seam appears to hold about the same stratigraphical
position as that known as the Battery Rock coal in Gallatin
county, which is the lowest workable seam in Southern Illinois.
Its development in Jackson county is somewhat local, and
appears to be restricted to the township in which the mines are
located. It has not been found in Randolph county, though the
lower portion of the coal measures are there well exposed. At
Murphysboro, twelve miles southeast of the Rattlesnake mines,
no indications of its presence has been found, though it may be
the equivalent of the seam near Makanda, in the south-east
corner of Jackson county.

The two following borings in Southern Illinois were made and
reported by Mr. Wm. McDonald. One was made three miles
southwest of Harrisburg in Saline county, and the other near
New Burnsjde in Johnson county. The latter probably com-
mences below the lowest stratum reached in the former, mid
ends before reaching the bottom of the coal measures.

The following is a condensed copy of the record of the boring
in Saline county:

No. Ft. In.

1. Surface soil and clay 14

]. Sandstone and shale Cl

3. Limestone 0 <>

4. Black slate 0 9

£5. Coal, (Coal No. 6) 2 4

«. Fire clay 1

7. Sandy shale and sandstone 29 7

8. Limestone 1 9

9. Blackslate 3 8

10. Shale with limestone bands 22 4

11. Blackslate 0 6

23. Coal (coal No. 5) 4 10

Total depth 142 3

The following is a condensed copy of the record of the boring
near New Burnside:

ECONOMICAL (JKOLOUY. .-,.->

Ft. In.

1. Surface soil 1

2. Sandstone and shale

3. Black shale 3 n

4. Coal , 1 3

5. Soft gray shale 2 1

al 3

7. Black shale 3 4

8. Fire clay 1 2

Total depth 75

A boring at Effing-ham, which commences in about the highest
strata of the upper coal measures, was carried to the depth of
1.170 feet, passing through three workable coals in that dis-
tance. For the following copy of the record of this boring I am
indebted to Walton Rutledge, Esq., Mine Inspector of that dis-
trict :

No. Ft. In.

1. Yellow clay 16

2. Hardpan 10

3. White sandstone , 6

4. Sandstone and shale %

5. Blue limestone 2

6. Black shale 3

7. Sandstone and shale 187

8. Limestone 2

'.'. Shale 7;.

10. Bituminous shale 1

11. Coal 0

12. Shale 35

13. Coal 1

II. Fire clay :>

15. Sandstone and shale 19

1C. Coal 0 8

17. Calcareous shale 6 4

18. Limestone 7

19. Blue shale 7

20. Limestone 7

21. Calcareous shale 3

22. Shale 44

23. Coal o :-j

21. Sandy shale 4 9

25. Coal 0 8

26. Shale 71 4

27. Black slate •>

28. Shale and sandstone i:;

29. Coal 1 2

30. Blue shale 7 KJ

31. Black slate 2

32. Shale, part sandy 53

33. Limestone 6

31. Black shale 4

35. Gray shale 52

56 ECONOMICAL (JKOLOGY.

No

Ft. 1

[n.

IJfi.

Black slate ,

12

157.

Shale, part sandy

=57

38.

Limestone

3

39.

Shale

23

40.

Limestone and calcareous shale....

30

11.

Gray shale and slate

117

42.

Black shale

10

9

43.

Coal

3

41.

Dark shale

3

45.

Limestone

3

46.

Slate ,

4

4

<J7.

Coal

4

ti

<!8.

Fire clay

3

2

09.

Limestone

10

70.

Sandstone

9

71.

Slate

2

72.

Coal

1

2

73.

Fire clay

, 0

10

74.

Dark slate

3

4

75.

Coal

4

8

70.

Gray shale

2

77.

Limestone

19

78.

Sandstone and shale

09

79.

Black shale

10

80.

Gray shale

7

Total depth 1,176

I regard the three coals near the bottom of this boring- as
the equivalents of coal numbered 5, 6 and 7 of the general sec-
tion, No. 5 being here a divided seam, and represented by Nos.
72 to 75 inclusive of the above record. They are all of suffi-
cient thickness to be advantageously mined, but the depth at
which they are found may prove a detriment to their i in me-
diate exploitation.

At Mount Veruon a boring with the diamond drill penetrated
a seam of coal 5% feet thick at the depth of 546 feet. No de-
tailed copy of the record could be obtained.

Record of a diamond drill boring at Galum creek, Perry
county, on the W. C. & W. K. II.

Surface soil and clay ...

Ft. In
17 0

Black shale ....

1 10

Dark blue limestone

8 8

Black shale

•_> (i

Coal No. 0

5 10

Fire clay

1 0

Limestone

1 3

Soft white shale...

2 3

ECONOMICAL GEOLOGY. 57

Ft. In.

Light gray limestone

2

Sandy shales

7

10

Hard white limestone

6

7

Hard gray shale

2

Hard blue limestone

0

6

Coal No. 5

4

S

Fire clay

11

1

Limestone

0

9

Shalo

2

Sandv shale and sandstone

52

6

Blue shales with limestone nodules ,

5

3

Fossiliferous limestone

1

4

Black shale

8

3

Coal (Coal No. 4)

3

1

Gray clay shale ( " " ")

1

8

Coal ( )

0

a

Dark shales with sulphur nodules

2

4

Gray shales

1

7

Black shale with limestone nodules

6

3

Shale

13

ID

Black slate

2

1

Coal No. 3 ,

2

2

Shale

8

6

Limestone

0

9

Shale and sandstone

3

9

Shales with thin bands of limestone

15

7

Shale

9

8

Coal (Coal No. 2)

1

6

Clay shale and limestone. ( " " ")

1

5

Coal ( )

2

6

Fire clay

1

7

Gray shale and sandy limestone

1

4

Shales with limestone nodules

9

9

Shale

12

9

Sandstone

4

6

Black shales

1

11

Coal No. 1

3

j

Black slate

0

5

Dark sandy shales

8

7

Gray shale with limestone nodules

1

9

Shale

13

5

Coal (local)

1

7

Dark shale with limestone nodules

2

2

Sandy gray shales

6

9

Slate and shale with traces of coal

5

E

Shale s i

28

9

White sandstone with traces of coal

1

Coarse sandstone

14

s

Pebbly conglomerate

1

Total depth ...................................................................... 344 4

The boriiig of which the above is a correct record was made
on the line of the Wabash, Chester & Western R. R. in Perry
county. It shows the presence at that point of all the lower
-7

58 ECONOMICAL GEOLOGY.

coals from No. 6 to the bottom of the measures the boring
terminating in the pebbly conglomerate which lies at the base
of the coal measures in southern Illinois. For a copy of this
record I am indebted to the Hon. C. B. Cole of Chester.

NATURAL HAS AND OIL.

Deposits of natural gas have been found at various localities
in the State, but they were generally in the drift days that
overlie the stratified rocks. This fact has led the writer to
conclude that such deposits did not originate in the older form-
ations of Devonian and Silurian age, from which the main sup-
ply of this material is obtained in Ohio and Pennsylvania, but
had been generated in one of the old peaty soils, which are in-
terstratified with the drift clays, and are found intact over ex-
tensive areas in Illinois.

Since the publication of Arol. VII of these reports, several dis-
coveries of this kind have been made, among which are two in
the edge of DeWitt county, eight miles west of the city of Clin-
ton, which are worthy of special notice. In the summer of 1885,
Mr. James Barnet, who resides at the locality given above,
while boring for water, found gas at two localities on his farm.
The first well was carried to the depth of ninety-six feet below
the surface, when a flow of gas was encountered with a pressure
of about twelve pounds to the square inch. Abandoning his
search for water there, he moved his tools to another locality
but a short distance away, and at the depth of 137 feet he ob-
tained another flow of gas with a pressure of thirty pounds 1o
the square inch. This hole wa.s tubed and pipes laid to his
dwelling, where the gas was utilized for heating and cooking-
purposes. When the gas producing stratum was reached, sand
and pebbles where thrown to the surface, indicating clearly the
porous character of the material in which the gas had been
confined. The following beds were encountered in boring the
deepest well:

Ft.

Soil and yellow clay 15

Blue clay 30

Black soil with wood, &c 3

Drab clay 8

Black mold and drift wood 8

Drajb colored clay 20

ECONOMICAL GEOLOGY. 59

Drift wood (log?) 2

Drab colored clay 21

Hardpan 12

Drab colored clay 3

Greenish clay 10

San*), &e 5

Total depth 137

The sand bed at the bottom of this well served as a recepta-
cle for the gas. which was held imprisoned by the impervious
given clay above until it was penetrated by the drill, and thus
given a free outlet to the surface.

Indications of the presence of gas in the drift clays have been
ol iserved at several localities in northern and central Illinois,
but whether it is generated in the deposit where it is found, or
in the stratified rocks below, is an unsolved problem, that must
b«> settled by future investigations. Its presence is purely local,
and two boring's with the diamond drill at Clinton, which
passed entirely through the drift deposits, and extended into
the underlying coal measures failed to reveal the presence of
gas at either point.

In 1871, gas was found on the farm of Win. A. Wilson, in
Macon county, ten miles south-east of Decatur, at the depth of
forty-five feet below the stir-face. It was stored in a bed of
quick sand below a deposit of hardpan, and was encountered at
several localities on the farm. The bed of quicksand was pene-
trated to the depth of fifteen feet without reaching the bottom.
The character of the underlying bed was not determined, but if
it was shown to be one of the old mucky soils frequently inter-
stratified with the drift beds, that would furnish a possible ex-
planation of the origin of the gas. Mr. Wilson utilized the flow
by conveying it to his dwelling, where it was used for a time for
both light and fuel.

A quarter of a mile east of this gas well a boring was made,
which passed through a bed of black soil, but no gas was found.
This might be due to the character of the overlying stratum,
which may have been too porous to prevent the escape of the
gas to the surface.

(las from the superficial deposits of drift clay and gravel, has
been found in numerous localities in Illinois, but generally not
in such quantity as to justify any attempt to utilize it for do-
mestic uses. The counties of Champaign, Bureau. LaSalle, Liv-

60 ECONOMICAL GEOLOGY.

ingston, McLean and Madison are among those in which such
discoveries have been made.

The only localities in this State where productive gas wells
have been obtained in the stratified rocks are Litchfield, in
Montgomery county, and in a well but just completed at Beards-
town, on the Illinois river. The discovery at Litchfield was
made in 1879, by the Litchfield Coal Co., of which Mr. H. H.
Beach is President. -It was made in a boring at the bottom of
their coal shaft, carried down to the depth of 168 feet below
the coal seam mined at that point, and the gas was encoun-
tered in a light colored sandstone, about 100 feet below coal
No. 1. No attempt was made to develop this gas deposit for
several years after its discovery by the Litchfield Coal Co., but
eventually a company was formed for the purpose of de-
veloping the oil and gas deposits of Montgomery county, under
the name of "The Litchfield Oil, Gas, and Fuel Company," and
at the commencement of the current year sixteen wells had been
sunk there, three of which were productive in gas, and three in
oil.

The productive wells are all on a nearly north and south line,
and those sunk on either side of this line, though but a short
distance from it, failed to prove productive. This fact indicates
the existence of an anticlinal, and the probable fracture of the
lower strata thus permitting the gas to rise to the sandstone
in which it is found. Hence the formation in which the gas is
generated cannot be certainly determined, and may be either of
Lower Carboniferous, Devonian or Silurian age.

The boring at Olney, the deepest one hitherto reported in
Southern Illinois, produced no gas, although carried down about
seven hundred feet below the base of the coal measures, and two
thousand feet below the surface.* It probably did not reach
Devonian strata, and therefore affords no evidence for deter-
mining whether or not the Devonian and Silurian rocks will
afford productive gas wells in Southern Illinois.

The Litchfield Oil, Gas and Fuel Company have succeeded in
introducing gas as fuel in many of the dwellings in Litchfield,

*The record of this boring may be fotmd on page 8, of Vol. VII, of these reports.

!!i "\nMTf AL GEOLOGY. (51

•

and at t IIP present time (February, 1887,) they have about 4no
meters in use with an average consumption of about 1,500 feet
each per (lay.

Three oil wells were in operation at the above date, affording
an average yield of seven or eight barrels of crude oil per day.
oi' a little more than two barrels j>er day to each well.

The well recently sunk at Beardstown to the depth of 1,070
feet, obtained a flow of artesian mineral water amounting to
about 800 barrels per day. Both oil and gas was found here,
the latter, although not fully te>te<l. is supposed to have a
-ure of several hundred pounds to the square inch, but the
quantity of oil is only about half a gallon per day. The princi-
pal flow of gas appeared to come from the Trenton limestone.*
The following record of this well was furnished by Dr. H. Ehr-
hardt. President of the company:

Feet

1. Drift clay, sand and gravel w

2. Limestone (Lower Carboniferous) 145

3. Kinderhook and Hamilton shales 250

4. I'.-rous Magnesian limestone (Niagara) 70

5. Shales and slat* (Cincinnati group) 125

6. Trenton limestone 375

7. St. Peters sandstone, penetrated only 15

Total depth 1,070

The first flow of oil and gas was said to have come from the
lower portion of No. 3. which probably represents the horizon
of the Devonian system, but the principal flow of water came
from the St. Peters sandstone. The company will probably put
down some additional wells to further test their territory.

The gas question has excited considerable interest in the pub-
lic mind for the last two or three years, in consequence of the
discoveries made in Ohio and Pennsylvania, and several experi-
mental wells have been sunk in search of this much desired fuel,
but with the exception of the one at Beardstown. none of them
have proved successful. Most of the borings made in central
and northern Illinois for artesian water have b««en carried down

*The first flow of oil and gas was found in the Devonian rocks, but was thought to
increase in quantity when the drill penetrated the Trenton limestone.

62 ECONOMICAL GEOLOGY.

into the St. Peters and Potsdam sandstones, but none of them
hitherto reported, except the well at Beardstown, have pro-
duced either gas or oil in paying quantities.

The boring at Rivertou, seven miles east of Springfield, was
carried to the depth of 2,004 feet below the horizon of coal No.
5, and about 1,380 feet below the base of the coal measures.
From the detailed record furnished by Mr. Swan, under whose
direction the work was done, it is impossible to define the exact
horizon where the bore terminated, but it undoubtedly passed
entirely through both the productive gas horizons of Ohio mid
Pennsylvania. Neither oil, gas or artesian water was found in
this well.

The artesian well at Carthage, in Hancock county, encoun-
tered the St. Peters sandstone at the depth of 975 feet, where
a fine flow of mineral water was obtained, but no indication of
the existence of any productive deposit of oil or gas was ob-
served.

The artesian well at Monmouth reached the St. Peters sand-
stone at the deptji of 1,088 feet, but no flow of water was ob-
tained, and no indication was found of the presence of gas or
oil. At Canton in Fulton county a well was bored through
both the gas producing horizons without obtaining either gas
or artesian water, and in northern Illinois many successful
artesian wells have been sunk, all passing through the Trenton
limestone, the lowest formation from which gas has as yet been
obtained, without in a single instance obtaining gas sufficient
to justify its utilization.

At Canton, a boring was made to the depth of 2,333 feet by
Messrs. Atwater & Co. in search of artesian water, which proved
a failure. The St. Peters sandstone was reached at the depth
of 1,415 feet, but no flow of either water or gas was obtained

from it.
The following is a condensed copy of the record of this well.

No. Feet.

1. Drift, clay, etc 92

2. Coal measure shales, etc 208

3. Lower carb. limestone 299

4. Kinderhook shales 171

5. Limestone (Devonian) 64

ECONOMICAL GEOLOGY. 63

Feet.

6. Limestone (Up. Silurian) 150

7. Shale, etc., (Cincinnati group) j50

v Trenton limestone 280

t». St. Peters sandstone 273

10. Calciferous limestone 100

11. Potsdam sandstone 54.5

Total depth 2 332

In all the artesian wells of northern Illinois, and they may be
counted by the score, not one except the well at. Beardstown
already referred to, has yielded any notable quantity of gas,
and with .such facts before me I have felt it to be my duty to
discourage any large expenditure of money in central or north-
ern Illinois, in attempts to develop productive gas wells in
those portions of the State.

In the eastern and southern portions of the State the condi-
tions are more favorable, but no experiments have as yet been
made that would justify the expression of a decided opinion
upon the gas question there. The only deep well bored in
southern Illinois of which I have been able to obtain the record
is that at Olney. which is given in detail on page 8, of Vol.
VII. of these reports. Although this boring was earned to the
depth of 2.000 feet, yet it did not reach the base of the lower
carboniferous limestone, and therefore affords no evidence in re-
gard to the development of the gas producing formations of
Ohio and Pennsylvania, which lie from 1.000 to 1,500 feet
below the lowest stratum penetrated in the Olney boring.

The Devonian system is fairly well developed in southern Illi-
nois, attaining a maximum thickness of 350 to 400 feet. The
following divisions of the system have been recognized :

Feet.

Hamilton limestone g<j

Mair-ellus shale 20

Corniferous limestone 25

Onondaga limestone 30

Oriskany sandstone -jOo

All these divisions are highly fossiliferous, and some of them,
notably the corniferous limestone, possess the dark color and
fetid odor which usually characterize the oil and gas produc-
ing rocks. These beds thin out rapidly to the northward, and
at the mouth of the Illinois river in Jersey county, the only

64 ECONOMICAL GEOLOGY.

representative of the entire series is about ten or twelve feet of
Hamilton limestone, intercalated between the Niagara and the
lower carboniferous series.

The next outcrop in a northerly direction is in Rock Island
county, where the Hamilton limestone and shale is somewhat
thicker, attaining a thickness above low water level of the Mis-
sissippi of fifty to sixty feet. On the eastern border of the
State no outcrop of this formation is known, but it was pene-
trated with the diamond drill at Tuscola in their search for
coal.

In LaSalle, county the coal measures overlie unconformably
the Trenton limestone, both the Devonian and Upper Silurian
systems being absent, a phenomenon probably due to erosion
anterior to the carboniferous period. The geographical extent
of this erosion we have no data for determining at the present
time, but no great thickness of Devonian strata have yet been
revealed by the drill, either in central or northern Illinois, and,
as the lower gas horizon, the Trenton limestone, has failed to
yield it in notable quantity in any of the numerous borings
made through it, the writer has not been disposed to encourage
any considerable expenditure of capital in searching for natural
gas in this State.

ARTESIAN WATER.

Three successful attempts to obtain artesian water have been
made in western Illinois since the publication of Vol. VII, of
these reports. Two of these are in Hancock county, one at the
Riverside Sanitarium near Hamilton, which is located at the
top of the bluff of the Mississippi river nearly opposite the city
of Keokuk, and the other at Carthage on the prairie which
forms the watershed between the Mississippi and the Illinois
rivers.

The Hamilton well obtains its flow from the Niagara lime-
stone which was reached by the drill at the depth of 680 feet.
The flow from this well is estimated by Dr. Ringland, the pro-
prietor of the Sanitarium, at 50,000 gallons per day, which I
feel inclined to regard as an over-estimate. The water was said
to rise in a rubber tube to the height of sixty-three feet above
the surface.

ECONOMICAL GEOLOGY. 65

The record of this boring describes the formations passed
through as follows :

Feet.

1. Earth (soil, clay, etc) 25

2. Limestone 100

3. Flint 05

•L Limestone 150

5. White soapstone 125

6. Blue soapstone 175

7. Mostly flint 55

8. Lime, sand and water 25

Total depth 680

a. 2 and 3 are undoubtedly Keokuk limestone. No. 4 Bur-
lington limestone. Xos. 5 and 6 Kinderhook shales, and Nos. 7
and 8 are Devonian and Upper Silurian limestones.

When the stratum from which the Hamilton flow comes was
penetrated in the ^ Carthage well, the water raised to within
fifteen feet of the surface and remained there, indicating a dif-
ference in the surface level at the two localities of about 75 feet.
This well was continued down to the depth of 975 feet, when,
on reaching the St. Peters sandstone, a fine flow of water was
obtained, but it failed to rise more than about five feet above
the surface. Subsequently the boring was continued down to
the Potsdam sandstone, without obtaining, however, any
decided increase in the flow of water.

Unfortunately no accurate record of this well was kept, but
the following data to the St. Peters sandstone was given me
from memory by the foreman in charge of the work:

Feet.

1. Drift clay, sand and gravel 214

•_'. White limestone 70

3. Shale 355

4. Limestone 336

- • . Peters sandstone

No. 2 is undoubtedly the Burlington limestone. No. 3 includes
the Kinderhook shales, the Devonian and Upper Silurian and
tht- Cincinnati shales, and No. 4 the Trenton limestone.

The water from both these wells is so highly charged with
mineral matter as to render it unfit for culinary use.

The third well was sunk tt Beardstown on the Illinois river
and but a few tVet above the flood plain of that stream. This
-8

66 ECONOMICAL GEOLOGY.

well was undertaken in the expectation of finding natural g«-is
in which the company were measurably successful, and the
details of the record are given on a preceding page. The first
ilow of water, gas and oil was obtained soon after passing
through the Kinderhook shales and in strata that are probably
of Devonian age, but this was thought to be increased on pass-
ing through the Trenton limestone. The flow of water is esti-
mated at 800 barrels per day, but no successful attempt lias
been made to measure the pressure of the gas. The production
of oil is only about one-half gallon per day.

A boring at Moumouth in Warren county failed to obtain a
flow of water, although carried down through the St. Peters
sandstone, which at that locality was reached at the depth of
1,078 feet. The following record of this boring was furnished
by Mr. J. H. Southwell of Rock Island.

No. Feet.

1. Drift clay 07

2. Coal measure shale 5

3. Burlington limestone %

4. Kinderhook shale 121

o. Devonian shale and limestone 109

0. Niagara limestone 08

7. Cincinnati shale 83

8. Trenton limestone 52(i

'J. St. Peters sandstone 151

Total 1,232

No indications of natural gas or oil were observed in this
well.

A boring was made at Jacksonville a few years since in search
of coal, but as it commenced near the bottom of the coal meas-
ures, the prospect of a successful termination of the experiment
was far from encouraging to any one conversant with the
geology of Morgan county. This boring was carried to the
depth of about a thousand feet, and I am indebted to Prof. H.
E. Storrs for a copy of their record, which I have summarized
as follows:

No. Feet.

1. Drift clay, &c 15tt

2. Coal measures, with one coal seam 100

3. Lower carboniferous limestone 433

ECONOMICAL GEOLOGY. . G7

4. Kinderhook shale 222

5. Devonian shale and limestone 19

G. Niagara limestone 75

Total depth. 1.002

The boring now being prosecuted there in search of natural
irns. is said to be down 1,600 feet, which, if true, would carry
the drill into the sandstones below the Trenton limestone, and
therefore quite through all known gas-producing horizons. The
St. Peter's sandstone which was encountered at the depth of
1,055 feet at Beardstown, must be found within thirteen or four-
teen hundred feet of the surface at Jacksonville, and below that
sandstone neither gas or oil has been found as yet in the Uni-
ted States in sufficient quantity to render ite exploitation a
matter of practical importance.

PART II.
PALEONTOLOGY OF ILLINOIS.

SECTION I.

DESCRIPTION OF FOSSIL INVERTEBRATES.

BY A. H. WORTHED.

INVERTEBRATES. 71

ORDER ZOANTHARIA.

GEM'S ZAPHREXTIS. Rafinesque.

ZAPHKENTIS DALEI. Edwards and Haime.

Zaphrentis spinuJifera. Hall.

PI. X, Figs. 12-12a.

This coral was described in the first Iowa report, Vol. 1, part
2, page 650. PI. 22, figs, la, Ib. Its date is 1858.

In 1851 Edwards and Hairae published a species which they
named Z. dalei (Mon. d. Pol. Foss. d. Ter. Pal.) from the same
locality, (Warsaw, 111.,) which is probably the same as Z.
spuiulifera, in which case the specific name dalei should have
precedence in accordance with the well established rules of
nomenclature. Hall's description is given below.

"Coral in the form of a reversed cone, curved. Calyx slightly
oblique, circular or sub-circular, the cavity deep ; septal fossette
strongly marked, situated on the inner side of the curvature.
Radiating lamellae strongly defined, somewhat irregularly curved,
numbering at the margin from forty-two to fifty, and uniting
in fascicles of two, three, four or more before reaching the
center; outer walls of the calyx thin at the upper margins, be-
coming very thick and strong below. Externally somewhat
rugose, and often swelling abruptly at intervals; the stages of
growth marked by somewhat regular rows of nodes or short
spines/'

The following is a free translation of Edwards and Haime's de-
scription of Z. dalei, from the same locality: ' 'Coral in the form
of an elongated cone, moderately curved ; external ridges irregu-
lar. Calyx oblique, sub-circular with a profound cavity. Fossette
rather deep and situated on the side of least curvature. La-
mellae sixty to seventy, well developed, thin, alternately a little

72 PALEONTOLOGY OF ILLINOIS.

unequal, generally reaching to the center where they are a little
curved, especially those adjacent to the septal fossette. Height
5 to 6 cent., diameter of the cup 2% to 3 cent. Locality, Warsaw,
111."

This description corresponds well with the form described sub-
sequently as Z. spinulifera, the principal difference being in the
larger number of lamellae in E. and H.'s specimen. This charac-
ter, however, is a variable one, and as there is no other form
known from that locality that has even as many as fifty
lamellae, it becomes almost certain that their specimen was
specifically identical with that subsequently described as Z.
spinulifera,.

The form from the Keokuk limestone that has usually been
called Z. dalei, has only about 36 to 42 lamellae, and agrees
well with the form described by the above named authors under
the name Z. centralis, to which I have no hesitation in referring
it. The specimen figured on PL X, figs. 12-12a, belongs to the
lower or Warsaw division of the St. Louis limestone, and was
found by the writer at Warsaw, 111.

No. 2556 of the Illinois State Museum.

ZAPHRENTIS CENTRALIS, Edw. and Haime.

PI. IX, Figs. 1-la. PL X, Figs. 13-13a.

Coral in the form of a curved cone, moderately elongated,
without prominent transverse ridges; cup deep, circular; septal
fossette large, central, and prolonged on the side of least curva-
ture; lamellae forty to forty-two, strongly developed and arranged
usually in four groups.

Heighth of a mature specimen 3 inches; breadth of the cup
1% inches. A smaller specimen measures 2% inches in length, and
breadth of cup 1% inches.

Position and locality: Keokuk limestone, Warsaw and near
Plymouth, 111.

Collector, A. H. Worthen.

No. 2563 of the Illinois State Museum.

NOTE.— Edwards and Haime in their description of Z. dalei, do not mention the short
s' incs that ma be observed on specimens that have not been weathered, but the^eare
oiten obliterated on specimens that have been long exposed to atmospheric influences.

INVERTEBRATES. 73

ZAPHRENTIS SPINULOSA, Edw. and Haime.

PL X, Figs. 6-tia.

Coral turbinabe, moderately elongated, a little curved and
slightly distorted, with a few irregular external ridges; epitheca
thin and on the lower portions ornamented with little sub-
spiniform points; cup circular, moderately profound; fossette
moderately developed, situated near the wall but in a variable
position from conforming to the curvature ; lamellae about thirty,
very feebly curved near the septal fossette, with an equal number
of rudimentary lamellae.

Height of an average size specimen, 1% inches ; breadth of cup,
about % to % inch.

Position and locality: Chester, 111., Chester limestone.

Collector, A. H. Wort-hen.

No. 2559 of the Illinois State Museum.

ZAPHRENTIS CHESTERENSIS. (sp. nov.)

PL IX, Figs. 3-3a.

Corallum elongated, moderately curved, gradually and regu-
larly tapering; calyx circular, not deep, fossette deep, and
situated on the side of shortest curvature. Lamellae in four
divi visions, the two on either side of the fossette to the number
of seven or eight coalesce before reaching the bottom of the
calyx. On each side of the strong septum opposite the fossette,
there are twelve or thirteen lamelke that extend singly to the
bottom of the cup. Surface slightly rugose, with traces of short
spines scattered irregularly over it.

This is a vnricty of Z. si>inuloxa, K. and H., but may be
distinguished by its more elongated and symmetrically
form, and greater number of lamellae.

Height 211/]«; diameter of calyx, 1% in.

Position and locality: Chester limestone, Monroe and Ran-
dolph counties.

Collector, A. H. Worthcu.

Xo. 2560 of the Illinois State Museum,

—1)

74 PALAEONTOLOGY OF ILLINOIS.

ZAPHRENTIS PELLAENSIS. (sp. uov.)

PI. IX, Figs. 6-Ga and PI. X, Fig. 11-lla.

Corallum turbinate, regularly curved, height of an average
specimen 1% in., diameter of calyx about % in., depth of cup %
in.; sides descending abruptly, the lamellae on each side of the
fossette to the number of four to six coalescing, while the others
extend singly nearly to the center of the cup. Fossette narrow
and situated obliquely to the curvature of the corallum. Whole
number of the principal lamelke 32 to 36 with about the same
number in the secondary series. Surf ace moderately rugose and
often marked by a few short scattering spines that are usually
restricted to the lower portion of the corallum.

This form is closely related to Z. spinulosa, E. & H. from the
Chester beds, but is usually shorter in proportion to its dia-
meter, and coming from a different geological horizon it is entitled
to be considered as a distinct variety.

Position and locality: St. Louis shales, near Pella, Iowa.

Collector, A. H. Worthen.

No. 2605 of the Illinois State Museum.

ZAPHRENTIS CALCARIFORMIS. Hall.

PI. X, Figs. 2-2a.

This form was described in the Thirty-fifth Annual Report of
the New York State Museum of Natural History, page 33, as a
Devonian species, from the Falls of the Ohio. The following is
the original description.

"Corallum simple, narrowly turbinate, regularly curved; dia-
meter of calices in individuals of the same height varying from
ten to fifteen millimeters; height twenty-five millimeters: ex-
terior with frequent undulations and low rounded annulations:
fossette narrow, very deep, commencing at the center and con-
tinuing to the posterior margin ; the lamellae extend to the
margin; coalescing and forming vertical walls; number of
lamellae fifty, alternating in size; at a distance of two milli-
meters from the margin the smaller lamellae coalesce with the
others."

The specimen figured is an unusually long one, but presents
the usual characters of the species.

INVERTEBRATES. 75

Position ami locality: Wnrsnw division of the St. Louis
limestone, Coalsburg, Ky.
Collector, E. O. Ulrich.
No. 2558 of the Illinois State Museum.

ZAPHRENTIS CAKINATUS (sp. nov.)

PL X, Figs. 3-3a.

Corallum curved, strongly compressed laterally; calyx deep,
ovate; septal fossette extended on the side of least curvature.
Primary lamella? about thirty, with about the same number of
very short secondary lamellae intercalated between the primaries.

Length 1% inches; breadth of calice on its widest diameter %
inch; opposite diameter of the same % inch; depth of calice %
inch.

Position and locality : The specimen figured was obtained at
Beutousport, Iowa, and probably belongs to the Keokuk or
St. Louis limestone, both of which outcrop in the vicinity.

Collector. A. H. AYorthen.

Xo. 2564 of the Illinois State Museum.

ZAPHRENTIS CLIFFORDANA. Edw. and Haime.

PI. X, Figs. l.la. Ib.

• •Corallum in the form of a curved cone, external ridges not
prominent, epitheca thin, making visible the ribs series of which
;)?•«• «'qual, plane and rather elosp. (Yilicc circular and rather
dcpp; fossette rather large and situated on the side of least
curvature: lamella? thirty-two to thirty-six, sub-equal, strong,
a little thickened outwardly and thinning towards the interior,
reaching generally to the center of the upper floor on which
tlipy are a little curved, and not elevated. Their free border
appears to be cut obliquely. One distinguishing feature of the
species is the equal number of rudimentary and primary
Lamellae."

The above description applies very well to a common form of
Zaphrentis in the Kinderhook beds of Illinois, and the speci-
mens figured are from that horizon in Monroe county.

Collector A. H. Worthen.

Xo. 2570 of the Illinois State Museum.

7C PALAEONTOLOGY OF ILLINOIS.

/AI'HRENTIS ULUICHI, (sp. HOV.)
PI. X, Figs. 10-10a.

Corallum small, pointed, compressed and slightly curved; cup
ovate, shallow; septal fossette comparatively wide, extending
from the center to the margin of the cup on the side of least
curvature.

Lamellae fifty-two to fifty-four on the outer margin, but coal-
escing in pairs about one-third the distance from the margin to
the center of the cup, so that only about twenty-six reach the
central fossette.

Length of a medium size individual % inch ; width of the cup
across the greatest diameter % inch; in the opposite direction
%6 inch.

This species is closely related to Z. cakariformis, Hall, from
the same horizon, (erroneously assigned by the author of the
species to the Corniferous limestone,) but differs from that in
its compressed, and more rapidly expanding form.

Position and locality: Warsaw division of the St. Louis lime-
stone, Coalsburg, Ky.

Collector, E. O. Ulrich.

No. 2573 of the Illinois State Museum.

ZAPHRENTIS LANCEOLATUS. (sp. nov.)

PL X, Figs. 4-la.

Corrallum small, pointed at the lower extremity, com pressed,
lanceolate, widening regularly from the pointed extremity to the
upper margin of the cup; septal fossette well developed, and
ranged in direction with the greatest diameter of the cup.
Lamellae twenty-two to twenty-four, all reaching to the border
of the septal fossette.

Length of an average size specimen 13/i0inch; breadth across
the greatest diameter of the cup, %« inch; the broadest speci-
men seen measured in length 10/iG inch; breadth of cup across
its greatest diameter, °/16 inch; in the opposite direction, °/ln
inch.

Position and locality: Warsaw beds of the St. Louis group,
Spergen Hill, Indiana, and Coalsburg, Ky.

Collector, E. O. Ulrich.

No. 2572 of the Illinois State Museum.

INVERTEBRATES. 77

/Al'HKKNTIS ILI.1NOIEXSI8. (sp. DOV.)
PL IX, Figs. 4^4a.

Corrallum very broadly turbiuate, cup oblique, surface marked
•veral transverse undulating ridges and numerous longi-
tudinal stria-. Septal fossette deep and situated on the side of
least curvature; lateral fossettes narrower but distinct, separat-
ing The lamelhe into three well marked divisions, the two on
either side of the septal fossette consist of ten or eleven each,
and the other of twenty-eight, making thirty-eight to forty
primary lamelhe in the entire cup.

This species was evidently sessile, and was attached near the
lower extremity to some cylindrical body, the scar of attach-
ment being visible on nearly all the individuals seen.

Length of a large individual 2% indies : breadth of cup 2Vi«
inches; depth of the same about 1 inch.

Position and locality: Keokuk limestone. Warsaw, and near
Plymouth. Hancock Co., 111.

Collector, A. H. Worthen.

NO. 2.~>G2 of the Illinois State Museum.

ZAPHRENTIS SPERGENENSIS. (sp. nov.)

PL X, Figs. 8-8a.

Corallum small, tnrbinate. straight or slightly curved at the
lower extremity. Surface striated longitudinally, and charac-
terized by numerous short spines irregularly distributed over
the entire corallum. Cup circular and proportionally rather
dec].: septal fossette well defined, with a narrow lateral fosset te
on cither side, separating; the lamella* into three divisions.

Primary lamelke twenty-two, with about an equal number of
ondary order, the latter coalescing with the others at
about half the distance from the border of the cup to the cen-
ter. On each sidfi-of the septal fossette, and between that and
the lateral foe there are five primary and five secondary

lamella-, that coalesce into one before reaching the center of

the cup.

Length of a medium size specimen % inch : breadth of cup, %
inch: depth of the same, 3/16 inch.

78 PALEONTOLOGY OF ILLINOIS.

Position and locality: This little coral is common in the
Warsaw beds at Spergen Hill, Indiana, and at Warsaw, 111.
Collector, A. H. Worthen.
No. 2574 of the Illinois State Museum.

ZAPHRENTIS VAKSOVIENSIS. (sp. nov.)

PL X. Figs. 9-9a.

Corallum small, turbinate, pointed below, and slightly curved;
epitheca thin, external stria? distinct ; height of corallum 1 inch;
breadth of cup, 7/ie inch; depth of the same, % inch.

Septal fossette nearly central, and extended on the side of
greatest curvature; primary lamellae comparatively strong, and
numbering about twenty-six, all reaching the thickened border
of this septal fossette.

Position and locality: This symmetrical little species is quite
common in the Keokuk limestone, at Warsaw, Hamilton, Nnu-
voo and Keokuk.

Collector, A. H. Worthen.

No. 2557 of the Illinois State Museum.

ZAPHRENTIS CYLINDRACEUS. (sp. nov.)

PL IX, Figs. 5-5a.

Corallum long, cylindrical, slightly curved, tapering at the
lower extremity. Surface marked by numerous transverse un-
dulations and fine longitudinal striae. Cup shallow', the center
slightly elevated as in the genus Anisophyllum. Septal fossetle
situated on the side of least curvature, and not reaching to the
center of the cup. Lamellae about thirty-two to thirty-four,
which coalesce in several groups before reaching the central
elevation.

Length, 2% inches; breadth of cup % inch.

Position and locality: Chester limestone, Chester, 111.

Collector, A. H. Worthen.

No. 2561 of the Illinois State Museum.

ZAPHRENTIS REVERSA. (sp. nov.)

Coral very broadly turbinate, the length being but little more
than the breadth of the cup; moderately curved, epitheca thin
and interspersed with numerous rather stout spiniform points,

INVERTEBRATES. 79

irregularly distributed over the whole surface; cup nearly cir-
cular, moderately profound: fossette large and situated on the
side of greatest curvature: lamella? about forty-four, those on
either side of the fossette to the number of about ten coalescing
before reaching the center of the cup.

This species may be distinguished from the large allied forms
by tin.1 size and position of the septal fossette.

Height.. 1°/1(, inches; breadth of cup, 1% inches.

Position and locality: Warsaw division of the St. Louis
group, near Columbia, Monroe Co., 111.

Collector, A. H. Worthen.

No. 2567 of the Illinois State Museum.

ZAPHREXTIS PARASITIC A. (sp. nov.)

PL X, Figs. 5-5a.

Corallum small, truncated at the lower extremity, slightly
expanded and compressed: breadth of the calice a little more
than the length: surface marked with strong longitudinal
striae: septal fossette comparatively large, central, extending
laterally on the side of greatest curvature; about twenty strong
lamella? extend from the border to the central fossette. Calice
deep, and irregularly ovate in form.

Length 3/1(. inch; greatest breadth of calice about % inch.

The specimen figured is parasitic on the ventral valve of Pro-
diH-tus pyxiflatus.

Position and locality: Kinderhook group. Clarksville, Mo.

Collector. A. H. Worthen.

Xo. 2571 of the Illinois State Museum.

GENUS LOPHOPHYLLUM, Ed. & Haime.

LOPHOPHYLLUM PROFUNDUM. (sp. HOV.)
PL X. Figs. 1-l-Ma.

Corallum turbinate, straight or curved, tapering regularly to
a pointed base: epitheca thin ; surface marked by a few distinct
encircling wrinkles, and numerous longitudinal striae. Calice
circular and deep, frequently occupying one-half the entire length
of the corallum: columella prominent, pointed and lanceolate:

80 PALAEONTOLOGY OF ILLINOIS.

lamellae about fifty, each alternate one comparatively robust,
and extending to the bottom of the calice, while the others
become obsolete before reaching the bottom.

Length of an average size specimen % inch; breadth of calice
°/10; depth of the same 7/i« inch.

Position and locality: Coal measures. Lower division of the
LaSalle limestone, LaSalle, 111.

Collector, A. H. Worthen.

No. 2565 of the Illinois State Museum.

GENUS ANISOPHYLLUM. Edwards & Haime.
ANISOPHYLLUM? IOVAENSIS. (sp. iiov.)

PL IX, Fig. 7.

Corallum rather narrowly turbinate, slightly curved and
pointed at the extremity. Central node prominent. No clearly
defined septal fossett can be seen.

Lamellae about thirty, three of which are elevated above the
bottom of the cup, dividing it in four unequal divisions.

Height 1% inches ; width of cup % inch ; depth of the same % inch.

I am not aware that any examples of the above named genus
have hitherto been found in carboniferous strata, and hence
refer the above described species to Anisophyllum with some
doubt. It seems to be clearly distinct from Zaphrentis, and its
affinities seem to be with the above named genus. In some
respects it resembles the species described under the name
Zaphrentis cylindraceus, from the Chester limestone, but differs
from that in its shorter form, more elevated central node, and
in the possession of three elevated lamellae.

Position and locality. Calcareous shales of the St. Louis
limestone, Pella, Iowa.
Collector, A. H. Worthen.
No. 2568 of the Illinois State Museum.

INVERTEBRATES.

GENUS TRACHYPORA. Edw. & Haime.
TKACHYPOKA AUSTIN:, (n. sp.)

PI. XI, Figs. 1-la. Ib. Ic, Id.

Corallum deiidroid, the branches generally cylindrical, some-
times irregular, from 15 to 25 rnm. in diameter, and infre-
quently divided. Corallites conical, diverging- from an imagi-
nary axial line to open on all parts of the free surface. The
calices all oval or circular, very variable in size, the larger
ones about 1.1 mm. in diameter, and either level with the
general surface, or with an elevated margin. Each orifice
is adorned with small tubercles or short ridges arranged in a
radiate manner around the calice margin. Openings of the
rorallites separated by dense calcareous tissue, of variable thick-
ness, but apparently always as wide ais, or wider than the
diameter of the tube orifices.

Sections show that the tubes are prismatic and in contact
uith each other, that their walls are greatly thickened by a
calcareous deposit on the inner side of the tubes, and that the
amount of the thickening increases toward the orifices. Mural
pores of large size are present, but apparently not numerous.
Tab uke are best developed in the axial region, where they cross
the tube cavity at intervals equalling once or twice the diam-
eter of the tubes. Tangential sections show that the corallile
cavities are surrounded by blunt, thick septal ridges. The
walls are now composed of fibre-crystalline calcite, and the
change lias destroyed the finer details of structure.

In all important respects the species here described resembles
the Trachypora ornata, Rorninger sp., from the Hamilton gr.
and I do not think any reasonable objection can be urged
against placing them in the same genus. Specifically they are
quite distinct, the corallum of Romiuger's species being much
smaller, the calices less variable in size and not so prominently
margined, nor are the interspaces so thick.

Position and locality: Coal Measures. Labette Co., Kansas.

Collector, A. C. Austin.

No. 2596 of the Illinois State Museum,

-10

82 PALEONTOLOGY OP^ ILLINOIS.

(JKxrs AMPLKXUS. Sowci-hy.
AMPLEXIS GKXICULATUS. (sp. nov.)

PI. X, Fig?.. 7-7a.

Coral cylindrical above the geniculate portion and pointed
below, and abruptly bent about half an inch above the lower
extremity so as to form nearly a right angle with the upper
part of the coral. Cup comparatively deep; lamellae twenty -four
or more; septal fossette not distinct on the specimens in lunid ;
septa rather thicker than the intervening spaces.

Surface marked by a few undulating transverse ridges, and
numerous longitudinal striae.

Its geniculate character alone will serve to readily distinguish
this species from any other known in the carboniferous rocks.

Position and locality: Chester limestone, Pope county, 111.

Collector, A. H. Worthen.

No. 256G of the Illinois State Museum.

INVERTEBRATES. 83

PAL.EOCRINOIDEA. Wachs, and Spr,

GENUS BATOCRINUS, Casseday.
BATOORINUS MONTGOMERYENSIS. (sp. nov.)

PL XII, Figs. 2-2a.

Batocrinus montgomeryensis, Worthen, March. 1884. Bui etin No. 2 of the Illinois State
Museum of Natural History, page 25.

Body below the arms spreading into a saucer-like form, more
than twice as wide as high, and composed of slightly convex
granulose plates. Dome inflated, nearly twice as long as the
body below,, and composed of nearly flat plates, each of which
has a small obtusely pointed node in the center. Ventral tube
central and apparently rather slender.

Basals short and forming a projecting rim around the colum-
nar facet. First radial series 3X5; the first one hexagonal or
heptagonal, nearly twice as wide as long. The second is quad-
rangular, about the same length as the first, and two-thirds as
wide; the third wider than long, axillary, and supporting the
first of the secondary series. The anterior ray has three second-
ary radials in each division. In the postero-lateral rays, the
secondary radial series consists of five plates, three on one side
and two on the other, the second plate on one side being an
axillary plate which supports on each side the tertiary radials.

The antero-lateral rays have two series of secondary radials,
consisting of two plates each, the upper one of which is axillary,
and supports a double series of tertiary radials.

This gives an arm formula of two arms to the anterior ray,
three each to the postero-lateral rays, and four each to the
antero-laterals.

First anal plate as wide as long, heptagonal, supporting three
plates above in the first series, five in the second, and three in
the third, the middle one of the last series projecting about one-
half its length above the others.

84 PALAEONTOLOGY OF ILLINOIS.

First interradial about as large as the first anal, and supports
twojmialler interradials above.

This species in its general form resembles Batocrinus biturbina-
tus, but the body is more spreading below the arms, the dome
is more inflated, with flat nodose instead of convex plates. Arm
openings directed upward.

Position and locality : Keokuk limestone, Montgomery county,
Indiana.

Collection of A. H. Worthen.

BATOCRINUS SUBCONICUS. (sp. nov.)

PI. XIII, Figs. 4-ia.

Batocrimts sulconicus, Worthen. March, 1881. Bulletin No. 2 of the Illinois Stato
Museum of Natural History, p. 20.

There is another form occurring near the same horizon as the
preceding, which resembles it somewhat in general form, but
possesses characters that render it clearly distinct. The calyx
is more expanded in proportion to its height than that of Ji.
montgomeryensis, and is composed of flat instead of convex
plates, with no projecting rim formed by the basal plates as in
that species.

The dome is obtusely conical, composed of convex plates, and
twice as long as the calyx below the arms, sloping up regularly
and symmetrically into a rather stout, central ventral tube.

The calyx below the a,rms is nearly four times as wide as high,
with the arm openings directed outward, and arm formula about
the same as in B. montgomeryenxis,. The specimen is so highly
silicified that the form and number of Ilic secondary <md teHiai-y
radials cannot be clearly determined.

Collection of A. H. Worthen.

BATOCRINUS UNIONKNSIS. (sp. nov.)

PI. XII, Figs. 5-5a, and PI. XIII, Fig. 3.

Body depressed globose, width at the base of the arms a little
greater than the height to the base of the ventral tube.

Plates of the calyx strongly beveled on their borders, leaving
a deep suture between them on all sides.

Dome elevated, composed of plates that are elevated in the
center, forming short and rather stout nodes.

INVERTEBRATES. 85

Basal plates very small and concealed in the basal cup. First
m dials once and a half as wide as the second, and projecting; so
as to form a prominent rim around the basal cavity.

Second radials quadrangular, nearly twice as wide as long.
Third radials pentagonal, axillary, and supporting on their upper
sloping sides the secondary series.

The secondary and tertiary radial series, consist of three
plates each, the last one of the third series giving support to
the first arm plates.

First anal plate hexagonal, and succeeded by two smaller ones
in a double series.

Arms composed of a double series of closely interlocking
plates.

Ventral tube slender; column unknown.

Position and locality: St. Louis division of the Lower Car-
boniferous. Union county, Illinois.

No. 2581 of the Illinois State Museum.

BATOTRINUS NASHVILL.E, Troost, sp.

PL XIII, Fig. 5.

This magnificent crinoid wa.s described and figured in the
(Jeology of Iowa, Vol. I, part 2, page G09, pi. XV, fig. 4, and
pi. XVI, figs. 4, a & b, under the name Actinocrinus nashvillte
Troost; but none of the specimens known at that time had the
remarkable ventral tube belonging to this species preserved,
and an individual in which that organ is well preserved, is here
illustrated.

The following is the original description of the species: "Body
urn-shaped, rounded at base and excavated for the reception of
the column, contracted above, and somewhat rapidly expanding
at the brachial margin; dome moderately elevated, with a strong
central proboscis. Basal plates more than twice as wide as
long, spreading in a broad thickened rim, indented at the line
of suture. First radial plates large, wider than long, tubereu-
lose transversely, and prominent above the other plates. Second
radials wider than long. Third radials supporting on the two
upper oblique sides, two hexagonal supra-radial plates, and these
support two brachial plates, from the upper sides of which pro-
ceed the arms, giving uniformly four arms to each ray. A small

86 PALEONTOLOGY OF ILLINOIS.

heptagonal intersupra-radial plate rests on the adjacent edges
of the first supraradials.

First interradial plates heptagonal or octagonal; the anterior
ones large, supporting two or three plates in the second and
third range each. First anal plate as large as the first radials,
strongly tuberculiform, supporting in the second range three
plates, and in the third range four, with some small plates in-
tercalated between the arms. Dome large, becoming proboscidi-
form. Surface granulose, the granules sometimes pustuliform.

Column large, consisting of strong joints separated by thinner
ones, and, farther from the body, by two, three, four or more
thinner ones."

In addition to the above description, I would add the follow-
ing: Ventral tube long, gradually tapering and rising symmet-
rically from the center of the dome, composed of massive hex-
agonal plates, nearly all of which are produced into a short
spiniferous node, and occasionally into a slender spine, half an
inch or more in length. About half the length of the ventral
tube above the dome a single row of six plates is replaced by
stout spines % of an inch in length, and about r>/ir> mcn in Di-
ameter at the base. These long spiniferous plates probably sur-
round the anal opening. Above this the plates are less massive
and diminish in size to the apex.

This fine species is only found in the Keokuk limestone, and
for the use of the specimen figured I am indebted to Mr. L. A.
Cox, of Keokuk, by whom it was kindly presented to the nuthor.

GENUS POTERIOCRINUS, Miller.

POTERIOORINUS SPINULIPERUS. (sp. UOV.)
PL XIV, Fig. 3.

Poteriocrinus spinnUferns, Worthen, March, 1884. Bulletin No. 2 of the Illinois State
Museum of Natural History, page 27.

Body of medium size, short, width three times as great as the
height to the top of the first radials; base depressed, under-
basals small and concealed under the first columnar joint. Col-
umn obscurely pentagonal near its upper extremity, becoming
round below, slender and composed of alternate thin and thicker
joints near the base, beyond which it is unknown.

INVERTEBRATES. 87

Basal plates forming a flat disk with slightly curving angles
above and below, so that the body if detached would rest on
the central portion of these plates. First radials short, penta-
gonal, twice as wide as high, angular below to fill the depres-
sions between the basals. Under a good lens they show rude
striations around their lower borders, with a slight depression
in the upper margin, forming a well defined suture between them
and the second radials. Second radial series on four of the rays
as long as their greatest breadth below, angular in front, and
compressed at the sides, the apex produced into a rather prom-
inent node, and support on the upper angles the first divisions
of the rays. The right antero-lateral ray divides again on the
sixth plate, and again on the sixth and twelfth, while the left
antero-lateral divides the second time on the sixth plate, and
the outer division again on the seventh or eighth plate, while
the inner one continues simple beyond the second bifurcation.

The anterior ray has five radial plates, the first correspond-
ing in form and size with those of the other rays, the second is
quadrangular, longer than wide, narrower above than below,
the third and fourth are quadrangular, about half as long as
wide, the fifth is about as long as wide, axillary and produced
into a strong node like the axillary plates of the other rays.

The right division of this ray divides again on the tenth plate,
while the left continues single as far as it is preserved.

All the axillary plates of the arms are nodose, and longer than
the others, which are slightly wedge-formed and give off strong
pinnules from their longer sides.

Position and locality: Chester limestone, near Columbia, Mon-
roe county, 111.

Collector, A. H. Worthen.

No. 2492 of the Illinois State Museum.

POTERIOCUIXUS ULRICHI. (sp. 11OV.)
PI. XVII, Fig. 2.

Calyx below the second radial plates cup shaped, about twice
as wide as high. Base concave, and underbasals concealed by
the column. Basals on the posterior side pentangular slightly
projecting on their upper margins, leaving a well defined suture
between them and the second radials. The second radials are

88 PALAEONTOLOGY OF ILLINOIS.

about twice as long as wide, strongly constricted in the middle
and sharply angular above.

Arms two to each of the posterior rays, the only ones pre-
served in the specimen in hand, composed of long rounded
joints, arranged in a somewhat zigzag position, and decreasing
in length towards their extremities. Pinnules strong.

Anal plates arranged as usual in this genus, and united above
to form a slender ventral tube, only the lower portion of which
is visible.

Column round, composed of short pieces that decrease in
diameter as the distance from the base increases.

Position and locality: Keokuk limestone", Keokuk, Iowa.

No. 337 of Mr. L. A. Cox's collection.

I take pleasure in dedicating this pretty species to my friend
Mr. E. O. Ulrich of Newport, Ky.

ELSAHENS1S. (sp. 11OV.)
PI. XIV, Fig. 5.

Calyx obconical, with straight gradually expanding sides.
Base truncated, the under basals forming a shallow cup about
three times as wide as high.

Basals large, the two on the anal side heptagoual, the others
a little smaller and pentagonal or hexagonal.

First radials rather smaller than the basals, pentagonal, and
excavated on their upper borders for the reception of the second-
ary radials.

Anal plates three, the first nearly as large as both the others,
and situated as is usual in this genus, the first resting between
the basals, the second resting on the summit of the left pos-
terior radial, and the third on the summit of the first.

Secondary radials, arms and column unknown.

Position and locality: Kinderhook group near Elsah, Jersey
county, Illinois.

Collector, A. H. Worthen.

No. 2560 of the Illinois State Museum.

INVERTEBRATES. 89

POTERlorUl.NTS XODOHASA US. (sp. UOV.)
PL XII, Figs. 3-3a, and PI. XIII, Pig. 6.

Calyx short, forming- a broad shallow cup below the brachial
series. Fnder basals visible around the column where they form
a small five-rayed star. Base depressed, basals prominent, and
projecting- below so as to form short transverse nodes. Radials
short, twice- as wide as long, pentagonal, and truncated squarely
across their upper margins.

Brachials one to each ray. pentagonal, rather larger than the
radials. wider than long and supporting on their upper angles
the first arm plates.

On the left antero-lateral ray. both divisions bifurcate again,
one division on the second, and the other on the fifth plate,
beyond which they appear to be simple to their extremities.

Anal plates five visible, arranged as is usual in this genus.

Column composed of thin pieces, and pentagonal where it
joins the body.

Position and locality: St. Louis limestone, Monroe county,
Illinois.

Collector, Henry Tolbot, Esq.

No. iTtTT of the Illinois State Museum.

PoTKIUOCRIXrS BUFFALOEXSIS. (sp. 1IOV.)
PL XII, Fig. 1.

Calyx small, obconic below the summit of the radial plates.
or about once and a half as wide as high. Basals small,
pointed above, forming a low pentagonal cup.

Badials two on each of the two rays visible, the first pentagonal
wider than high : the second quadrangular, and about twice as
wide as high.

Brachials pentagonal, wider than high, pointed above, and
supporting on their upper sloping sides the first arm phn •

Arm two to each of the rays visible, composed of rather stout
joints that are longer than wide, and project slightly at their
upi>er inner margins where they support stout pinnul

Anal series unknown.
—11

90 PAL.KX OTOLOGY OF ILLI N< >IS.

Column rather stout where it joins the body, composed of
slightly projecting plates that diminish gradually in size below.
Position and locality : Devonian shales, Buffalo, Iowa.
Collection of A. H. Worthen.

POTERIOCRINTJS ROWLEYI. (sp. 11OV.)
PI. XIV, Fig. !>.

Calyx short, cup shaped, twice as wide as high, with a well
defined suture betwreen the radial and brachial series.

Brachials on the anterior ray two, a little longer than wide.
the first quadrangular, and the second pentagonal, giving sup-
port on its upper angles to the first arm plates. These arms
continue single after their first bifurcation.

The right antero-lateral and the left postero-lateral rays,
have but one brachial each, which is pentagonal, length and
breadth nearly equal, and gives support to the first division
of the rays. These divisions bifurcate again on the fourth
plate, giving four arms to each of these rays.

Arms stout for a species of this size, composed of joints about
as wide as high, gradually tapering to their extremities. Anal
side not visible.

Column round, and composed of alternately thick and thinner
pieces, the former slightly projecting.

Position and locality: Chester limestone, Monroe county,
Illinois.

Collector, A. H. Worthen,

No. 2575 of the Illinois State Museum.

Named in honor of Mr. R. R. Rowley, of Louisiana, Mo.

POTERIOCRINUS SPINULIFERUS. (sp. 11OV.)
PI. XVII, Figs. 1-la.

Body short, saucer shaped, about three times as wide as high,
and composed of rather massive plates separated by well-defined
sutures.

Base depressed, and uuder-basals concealed in the basal de-
pression. Basals proportionally stout, pentagonal, the lower
angles curving into the basal depression. Radials short and
pentagonal, truncated squarely on their upper margins for the

INVERTEBRATES. 91

reception of the succeeding- plates. Brachials one each to the
posterior and antero-lateral rays, while the anterior ray has
four. The first brachial on this ra3' is about as long' as wide,
quadrangular, and like the corresponding plate on the other
rays, is constricted, rounded on the outer surface, and succeeded
by two short plates, the upper one giving- support to a nodose
axillary plate on which the first division of the ray takes place.
In this ray the outer division bifurcates a.gain on the tenth
plate, but the inner continues single as far as it is preserved.
The right antero-lateral ray bifurcates the second time on the
sixth plate, and both divisions again on the sixth to the
eleventh plate above, giving eight divisions to this ray. The
left antero-lateral ray has its first bifurcation on the sixth plate,
the inner division dividing again on the eighth plate, the outer
one continuing single as far as it can be seen, giving but six
divisions to this ray. The poster o-lateral rays bifurcate in the
same manner as the left antero-lateral ray, giving six divisions
to each of these rays, and twenty-nine to the entire animal.
The rays are composed of rather short, wedge-shaped pieces, that
decrease very gradually in width towards their extremities.

Five anal plates are visible, the two lower ones resting appar-
ently on one of the basals, an appearance that is probably due
to the partial displacement of the body plates by pressure.

Column round or slightly pentagonal, and composed of alter-
nate thin and thicker joints.

This crinoid has the general form of Zeacrinus, as defined by
\Vachsmuth and Springer, the only difference observable being
the mode of bifurcation of the rays.

Position and locality: Chester limestone, Monroe county, 111.

Collector, A. H. Worthen.

No. 2492 of the Illinois State Museum.

POTERKH KINTS MAMM.KFOHMIS. (sp. UOV.)

Body small, obconic or mamilhpform below the base of the
arms and squarely truncated below where it is united with the
column. Under-basals long and narrow, slightly angular at their
summits, forming a little cup about once and a half as wide as
high. Basals scarcely as long as the under-basals, but wider,
probably hexagonal and heptagonal. Primary radials two, the

92 PALEONTOLOGY OF ILLINOIS.

first nearly quadrangular, about twice as wide as high, the
second narrower, angular above, and supporting the first divi-
sion of the rays.

Whether a second bifurcation takes place above this cannot be
determined from the specimen in hand, but one arm is preserved
to the ninth plate without division. Anal series unknown.

Column composed of thin circular plates, with a, thicker one
intei'ealated at intervals of six to eight plates below its summit.

The only example of this species \ve have seen is too much
crushed for a complete diagnosis to be given, but its mamillate
form, and long under-basals, will serve to distinguish it from any
species known from this horizon.

Position and locality: Warsaw beds of the St. Louis forma-
tion, Warsaw, Illinois.

Collector, A. H. Worthen.

No. 2."i78 of the Illinois Stale Museum.

(iK\rs CALCKOCRTNUS. Hall.
CALCEOCRINUS ROBUSTTS. (sp. nov.)

PI. XII, Fig. 7.

Calyx subqnadrate with the upper lateral angles truncated
and sides constricted. Basal plate triangular, about three times
as wide as high. Lower dorsal plate triangular, .of about the
same width as the basal, and beveled below to fit the basal
plate. Dorso-lateral pieces twice as wide as high, with the upper
inner angles truncated for the reception of the succeeding plate.
Upper dorsal plate triangular, about once and a half as wide as
high, and slightly rounded at the lateral angles.

Dorsal arm robust, composed of six stout first radial plates,
the upper of which is axillary, giving support to the secondary
series of which there are three, the upper one an axillary plate
supporting the arms. The outer division continues single while
the inner one divides on the third or fourth plate, giving six
arms to this ray.

Lateral rays five, four of which are nearly equal in size, the
fifth quite small, and not preserved beyond the first bifurcation.
The first radial plate in the lateral rays is twice as long as wide,
that of the first lateral resting obliquely on the excavated outer

INVERTEBRATES. 93

angle of the dorso-lateral pieces. This is succeeded by a series
of radials so thoroughly anchylosed that the exact number can-
not be determined, two of which are protuberant, including the
axillary plate. One division of the ray probably divides again,
but the other remains single to its extremity.

Column round, comparatively rather stout, and composed of
slightly projecting pieces.

The specimen is silicious, and the surface markings, if any
existed, are thus obscured.

Position and locality: Keokuk limestone. Keokuk, Iowa.

Collection of Mr. L. A. Cox.

CAT/'KorKi\rs TUXK'ATrs, Hall, sp.

PI. XII, Fig. 6.

Calyx less massive than in the preceding species, basal plate
triangular, and about twice as wide as high. Lower dorsal
plate short, or about three times as wide as high. Dorso-lateral
plate six-sided, with a strong constriction on ther outer lateral
borders, and their inner angles truncated above for the recep-
tion of the upper dorsal plate. This plate is triangular, about
twice as wide as high, and slightly protuberant. The three first
plates of the dorsal ray are shorter than the six succeeding ones,
which are a little wider than long, and slightly protuberant.
The ninth plate is axillary, and supports the arms, which ap-
pear to be simple to their extremities.

Lateral rays five, of which only four are well preserved. First
radial series in these rays eight, including the long narrow series
that is arranged somewhat obliquely around the lateral sides of
the calyx. One or two of these in each ray, including the ax-
illary plate, are protuberant. Arms single above the first di-
vision on all the rays visible.

We refer this form to the species described in the Thirteenth
Report to the Regents of the N. Y. University, under the name
of Cheirocrinm tunicatus.

Position and locality: Keokuk limestone, Keokuk, Iowa.

Collection of Mr. L. A. Cox.

94 PALAEONTOLOGY OF ILLINOIS.

GENUS AGARICOCRINUS. Troost.
AGAKICOCRINUS NODULOSUS. (sp. nov.)

PL XIII, Figs. l-la.

Calyx of medium size, base deeply depressed, the basal de-
pression including; the basals, first radials, and the lower part
of the second radial plates. All the plates in the basal depres-
sion are smoother, and all above are strongly nodose. This
species has a tertiary series of radials, smaller than the second-
ary, giving; support to the first arm plates, which are also
nodose.

Dome pyramidal, with a series of large, strongly nodose, plates
immediately above the arm bases, the number of which is de-
termined by the number of arms in the ray. When the ray has
four arms, there are three of these plates, two immediately
above the base of the arms, and the third above and partly
between those below. When the ray has three arms, there are
two of these plates, and over the anterior ray, which has but
two arms, there is only a single large plate. These plates are
succeeded by about three rows of smaller plates, that extend
up to the large apical plate which crowns the summit. Anal
opening small, and situated just below the apical plate. The
anterior ray has two arms, the right anterior and t\vo pos-
terior rays four each, and the left anterior three, making seven-
teen altogether, which is probably an abnormal number.

This species may be distinguished from A. americanus, by its
tertiary radials, and by the strongly nodose character of all
the plates of the calyx, except those included in the basal de-
pression.

Position and locality: Keokuk limestone, Keokuk, Iowa.

Collector, Mr. L. A. Cox.

Collection of A. H. Worthen.

AGARICOCRINUS MACADAMSI. (sp. nov.)

PL XIII, Figs. 2-2a.

Calyx large, strongly inflated above the arms, and depressed
below, the basal depression including -the entire basal and radial
series.

INVERTEBRATES. <r>

I>asals and first radials smooth, second radials and succeed-
ing arm plates slightly nodose.

The anterior and left anterior rays have three arms each, and
the right anterior and the two posterior rays four each, making
altogether eighteen arms, which is probably the normal number.

Immediately above the arm openings there are from three to
four rather large nodose plates, while those forming the upper
part of the dome are smooth or but slightly elevated in the
center.

Anal area large, protuberant, and composed of twenty-four
or more nearly smooth plates, above which the anal opening is
situated.

The basal and radial plates are obscured by cherty material,
so that their relative size and form cannot be determined.

\Ve dedicate this fine species to the Hon. Wm. McAdams, of
Alton, by whom it was found.

Position and locality: Keokuk limestone, Jersey county, Illi-
nois.

Collection of A. H. Wortheu.

GENUS CENTROCRINUS. Wachsm. and Spr.

CKNTKOCKLXUS TEXNESSEEXSIS. (sp. nov.)

PI. XIV, Fig. 1.

Calyx broadly turbinate, breadth at the base of the arms
equal to once and a half its height.

The basal plates form a low pentagonal cup, about twice as
wide as high, with projecting lower borders, which form a rim
around the columnar facet.

The first radial plate is as large or larger than the second
and third combined, and has seven distinct angles.

Second radials quadrangular, about twice as wide as long;
third radials about the same size as the second, axillary, and
supporting the succeeding radial series, which in rays visible on
our specimen consists of a single axillary plate, giving four
arms to each ray.

One long oval plate fills each of the interradial spaces on the
free side of the specimen in hand.

The arms are not preserved beyond the fifth or sixth joint,
and the fifth plate on one arm seems to be an axillary plate.

'.)<> PALEONTOLOGY OF ILLINOIS.

and possibly a second division takes place in all the arms in
perfect individuals. Arms as far as can be seen, composed of
short quadrangular joints, about twice as wide as long.

Column round, and composed of alternately thick and thinner
joints, the former slightly projecting.

Position and locality: Niagara limestone, near Clifton, Wayne
county, Tennessee.

Collection of A. H. VVorthen.

GENUS AMPHORACRINUS. Austin.
AMPHOKACRINUS JEKSEYENSIS. (sp. nov.)

PI. XIV, Figs. 8-8a.

Calyx short, the radial series spreading laterally so as to form
a low shallow cup, more than three times as wide as the height
to the base of the arms. The basal plates project slightly below,
so as to form a rim around the columnar facet.

The specimen in hand has an abnormal structure, the anterior
ray being obsolete. The right posterior and the left anterior
divisions of the calyx have the normal number of three radials
to each ray; while the left posterior and the right anterior
divisions have but two radials each, the second being as large
or larger than the first and supporting the first arm plates.

Anal plates three, the first hexagonal, the second smaller and
quadrangular, resting upon the first, with two larger anals on
either side which rest partly on the lateral sides of the first
radials, and partly on the first anal plate. Above these four
anals, there are six "slightly protuberant plates arranged around
a small anal opening.

In the normal divisions of the calyx there is a single large in-
ter radial plate.

On the anterior side there are four plates rather larger than
the first four on the anal side, and arranged in the same
manner.

Summit composed of numerous nodose plates, a massive one
crowning the summit, as in some species of Agaricocrimm.

The specimen has six arms, one each to the posterior, and two
each to the antero-lateral rays.

Position and locality: Kinderhook group, Jersey county.

Collector, A. H. Wort hen.

No. 2582 of the Illinois State Museum.

INVERTEBRATES. 97

<ii:.Ms ACTINOCRINUS. Miller.

AiTIXOTIMXUB LOBATUS. Hall.

PI. Xn, Figs. 8-8a.

Body large, urn-shaped below the arms, and conical above, the
dome gradually diminishing- into a strong ventral tube com-
posed of strongly protuberant plates.

Masai plates nearly as large as the first radials, thickened
below so as to form a slightly projecting rim around the
column.

First radials large, length and breadth nearly equal, hexagonal
and hepta-ronal : second radials about half as large as the first,
and hexagonal: third radials smaller than the second, giving
support to two brachials. These are succeeded by a second and
third series of small brachials of which there are four or more
to each ray.

First interradial hexagonal, about the same size as the second
radial, succeeded by two smaller interradials, with a third and
fourth scries of still smaller interradials of three each.

First anal plate smaller than the first radials, hexagonal with
two smaller hexagonal plates in the second series, three in the
third series, and four in the fourth.

Surface of the plates traversed by ridges, which, joining to-
gether near the center of the plates, form short flattened nodes.

Arms composed of a double series of short interlocking plates,
and, on one of the specimens figured, showing numerous bifurca-
tions.

Position and locality: Keokuk limestone, Greene county, 111.

Collector, Henry Talbot, Esq.

No. 2583 of the Illinois State Museum.

GEMS EUPACHYrUIM S. Meek and Wortheu.
EupACHYCRraus ORBICULAIUS. Hall sp.

PL XIV, Figs.

This species was described in 18GO, in the Boston Journal of
Natural History as ScapbJOCTMUS orbirnlurix. The following is
the original description:
-12

98 PALEONTOLOGY OF ILLINOIS.

"Body below the arms very broadly basin-shaped, or de-
pressed hemispheric, with the upper margins inflected; articular
scar for the column attachment sharply impressed, extending
one-half or two-thirds the diameter of the basal plates.

Basal plates pentagonal, obtusely angular above, forming by
their union a pentagon with scarcely concave margins. Sub-
radial plates exceedingly large, extending from the edge of the
column to near the top of the first radial plates, three sub-
pentagonal and two heptagonal (or hexagonal from the straight-
ness of the lower sides), length somewhat greater than breadth.
First radial plates proportionally small, sub-triangular; the
lateral edges of the adjacent plates slightly truncating each
other. First anal plate large and massive, pentagonal, resting
between the two heptagonal sub-radials, and supporting one
side of the adjoining first radial plate. The two remaining anal
plates, (all of which are seen in the specimen,) are smaller and
hexagonal.

Arms and column unknown. Surface of plates depressed con-
vex, sutures distinctly marked. The body plates are very
massive, the internal cavity being less than half the whole
•iiameter."

Position and locality: Keokuk limestone, Keokuk, Iowa.

The specimen figured is in the collection of A. H. Worthen.

EUPACHYCRINUS? SANCTI-LUDOVICI. (sp. UOV.)

We have obtained from the St. Louis quarries some crushed
specimens of a form apparently belonging to the above named
genus, none of which are quite well enough preserved to admit
of a clear and full diagnosis, but differing so much from all
other crinoidal forms known from this horizon, that the crushed
specimens may be easily recognized when the general form is
known.

Body of medium size, basiii-shaped, base depressed, the under-
basals concealed in the basal concavity. Basals prominent, the
lower angles curving upward into the basal depression, their
upper angles extending nearly to the summit of the first radial
plates. First radial s pentagonal, their lower angles fitting into
the depression between the bawals, widest at their summits where
they are squarely truncated for the support of the second

INVERTEBRATES. 99

radials. Brachials as long as wide at bottom, constricted in
the middle, and supporting the first division of the rays. These
plates are all prominent in the center or sub-nodose, the axil-
lary plates more so than the plates below.

Some of the rays after their first division on the second radial
divide once or twice more on the fifth and sixth plate, and pos-
sibly all may do so, though that cannot be determined from the
specimen at hand.

Anal plates and column unknown.

Position and locality: St. Louis limestone, St. Louis, Mo.

Collector, A. H. Worthen.

No. 2579 of the Illinois State Museum.

GENUS BARYCRINUS, Wachsmuth.
BARYCRINUS SPURIUS. Hall. sp.

PI. XIV, Fig. 4.

Calyx broad basin-shaped, composed of massive depressed
convex plates. Uuder-basals spreading horizontally beyond the
columnar facet form a pentagonal disc. Basals hexagonal
counting three angles on their lower margins, except the one
on the anal side which is heptagonal.

First radial plates wide, the autero-lateral ones longer than
the others; second radials very short; third radial somewhat
longer, and both nearly as wide as the first. The third radial
is angular above, and gives support to two stout arms, com-
posed of massive plates about as long as the second radials.

First anal plate as large as the anterior basals, and hexa-
gonal counting thr/e angles on the lower margin. In the typi-
cal specimen figured in the Geology of Iowa, Vol. 1, part 2,
plate 18 figs. 7 and 8, there is a small quadrangular anal plate
intercalated between the large first anal and the right posterior
basal, but this seems to have been an abnormal character not
usually observed in this species.

This specimen has been figured to show the character and
arrangement of the arms.

Position and locality: Keokuk limestone, Warsaw, Illinois.

Collection of A. H. Worthen.

100 I 'A L/EONTOLOGY OF ILLINOIS.

BARYORINUS TUMIDUS. Hall. sp.

PI XIV, Fig. G.

Cyathocrinus tnmidus Hall. Geology of Iowa, Vol. 1, part 2, pago (i2l. I'l. XVIII, Figs.

1, a. b.

"Calyx basin form, shallow, the plates thick and tumid.
11; i sal plates small; their area nearly occupied by the column,
and presenting a small pentapetalous opening in the cenler.
Subradial plates with the bases nearly straight, pentagonal,
except the one on the anal side which is hexagonal; each plate
prominently convex or tumid. Radial plates somewhat un-
equal, very thick and broad, convex in the middle; articulating
faces nearly in a plane with the axis. First anal plate quad-
rangular, small.

Surface finely granulose or grauulose-striate towards the mar-
gins of the plates.

The base is more prominent than the surrounding subradi;il
plates; in which character it differs from ('. buUntiin, the sub-
radials being less prominent, and the radials larger and more
equal in size."

The above is the original description of this species, the type
specimen consisting of the calyx only. In the figured specimen
on PI. XIV, the arm formula is clearly shown. On three of the
rays, to-wit, the anterior and the posterior laterals, there are
two brachials, the first one very short and nearly as wide as
the radials, the second a little longer, obtusely angular above,
and giving support to the two divisions of these rays. On the
other rays there are no brachials, each sustaining a single arm
supported on the upper surface of the radial plates, giving eight
arms to each individual. Arms composed of massive plates,
decreasing very gradually in breadth from their base upwards.

Position and locality: Keokuk limestone near Hamilton,
Hancock county, Illinois.

Collection of A. H. Worthen.

GENUS DORYCRINOS. Itemer.
DORYCRINTTS MississiPPiENSis. Roemer.

PL XII, Fig. 4,

Body broadly urn-shaped, dome convex, with six long slender
spines, five of which are situated immedialy above the summit

INVERTEBRATES. 101

of the rays, while the sixth crowns the summit of the dome.
These spines are sometimes bifurcated as seen in the example
figured.

Bawal plates massive, spreading at their lower margins and
separated by clearly defined sutures. First radial plates hexa-
gonal, about twice as wide as long. The left antero-lateral ray
in the specimen figured has but two radials, the second of which
is an axillary plate, supporting on its upper sides two secondary
radials. In the other rays there are three radials, the second
of which is quandrangular in outline, the third pentagonal,
and gives support to two pentagonal secondary radials. These
are succeeded by four tertiary radials that support the arms,
the normal number of which is four to each ray. The plates
forming the dome are more convex than those below the arms.

Interradial plates three visible below the arms, the first large,
and heptagonal, the other two smaller and hexagonal. First
anal plate heptagonal, length and breadth nearly equal, and
supporting three smaller anals in the second series.

Column round and consisting near the summit of alternating
thicker and thinner joints, the latter increasing in number as
the distance from the body increases.

Position and locality: Keokuk limestone, Hamilton, Illinois.

This magnificent specimen was collected • by Mr. L. A. Cox,
by whom it was presented to the author.

Collection of A. H. Worthen.

102 PALEONTOLOGY OF ILLINOIS.

BRACHIOPODA.

GENUS DISCINA. Lamarck.
DISCINA VARSOVIENSIS. Worthen.

PL XI, Fig. 7.

Discina varsoviensis, Worthen, March, 1884. Bulletin No. 2 of the Illinois State Mu-
seum of Natural History, page 23.

Shell of medium size, ovate in outline, anterior and posterior
margins nearly equal in width. The larger or free valve is
crushed so that its general form cannot be clearly determined;
its surface, however, is ornamented around the borders with ten
to twelve or more rather strong and sharp concentric ridges,
which become less conspicuous or obsolete towards the apex.

The lower valve is nearly flat and marked around the border
by fine concentric ridges rather less conspicuous than those on
the other valve, with a long narrow slit or foramen extending
from about the center of the valve more than half way to the
posterior extremity, and surrounded by an elevated margin.

Length of an average size lower valve % inch; greatest breadth
of the same 10/16 inch.

Position and locality: Keo'kuk limestone, Warsaw, 111.

Collector, A. H. Worthen.

No. 2545 of the Illinois State Museum.

GENUS TEREBRATULA. Llwyd.
TEREBRATULA ROWLEYI. Worthen.

PL XI, Figs. 6,6a,6b.

Terebratula rowleyi. Worthen, March. 1884. Bulletin No. 2 of the Illinois State Museum
of Natural History, page 23.

Shell below the medium size, iuequivalve, conical; ventral valve
strongly convex in the middle from the beak to the basal mar-
gin, and rapidly sloping on either side to the lateral borders.

INVERTEBRATES. 103

Beak of the ventral valve pointed, slightly recurved, and ex-
tending beyond that of the opposite valve; both valves longer
than broad and sinuate in front. Dorsal valve slightly convex
at the umbo, where a shallow depression commences and widens
downward, and at the front occupies nearly the entire width of
the valve. Surface smooth or showing only very fine lines of
growth.

Length of ventral valve from beak to base 7/1B inch; greatest
breadth 6/1H inch; thickness of the shell with the valves united
about one-third the length from the beak to the front, % inch.

Position and locality: From a cherty bed near the base of
the Burlington limestone, Pike county, Mo.

Collector, R. R. Rowley.

No. 2526 of the Illinois State Museum.

GENUS ATHYRIS. McCoy.
ATHYRIS SQUAMOSA. Worthen.

PL XI, Fig. 2.

Athyris sqttamosus, Worthen, March, 1884. Bulletin No. 2 of the Illinois State Museum
of Natural History, page 24.

Shell of medium size, broadly ovate transversely, or nearly
circular in outline; valves depressed, and showing externally
five heavy imbricating or overlapping plates, that were covered
originally with short, coarse spines. Beaks depressed and closely
approximate, that of the ventral valve rather the most promi-
nent, and projecting beyond the other, with a perforated ex-
tremity.

Length from beak to base 10/1H inch^ greatest width of the
valves n/i<5 inch; thickness about 5/1H inch. This unique form
differs so strongly from all others in the Carboniferous forma-
tion that a comparison is unnecessary.

Position and locality: Oolitic beds of the St. Louis limestone,
Monroe county, 111.

Collector A. H. Worthen.

No. 2527 of the Illinois State Museum.

104 PALAEONTOLOGY OF ILLINOIS.

GENUS BHYNCHONELLA. Fischer.
RHYNCHONELLA ILLINOIENSIS. Worthen.

PI. XI. Figs. 3-3a,3b,3c.

Rhynchonella illinoiensis, Worthen, March, 1884. Bulletin No. 2 of the Illinois State
Museum of Natural History, page 21.

Shell of about medium size, transversely ovate to sub-circular,
wider than long, front nearly straight in the middle, beaks ob-
tusely pointed. Ventral valve t-lightly elevated near the beak,
and depressed towards the front into a broad, shallow nx'shil
sinus, which is occupied by about eight sub-angular plications
that interlock in front with those of the opposite valve. There
are also from eight to ten similar plications on each side of the
sinus.

Dorsal valve sharply depressed at the sides, nearly flat from
the beak to the front, which is elevated into a broad mesial
fold on which there are about eight elevated plications that in-
terlock with those of the opposite valve, and about the same
number on each side of the mesial fold. Length of an average
size specimen 6/1H inch; width % inch; thickness in front about
equal to the length. The small individuals of this species, if
found in Upper Silurian strata, might be mistaken for R. wil-
soni.

Position and locality: Coal Measures, Peoria county, 111.

Collector, Mr. Giffprd and W. H. Adams.

No. 2537 of the Illinois State Museum.

GENUS LINGULA.
LINGULA VARSOVIENSIS. Worthen.

PL XI, Fig. 8.

Liugula carsovieusis, Worthen, March, 1884. Bulletin No. 2 of the Illinois State Mus-
eum of Natural History, page 24.

Shell of medium size, longitudinally oblong, more than one-
third longer than wide, with sub-parallel sides, the broadest
part being a little below the middle of the shell.

Basal margin broadly rounded, beak rather prominent, an-
terior margin more narrowly rounded than the basal, but not
quite perfect in the specimen in hand.

IXVKKTEBRATKS. 105

Surface ornamented with numerous concentric striae, or fine
liii^s of growth that are most conspicuous on the borders of
the shell.

Length ir> ,„ inch: greatest breadth 9/le inch.

This species resembles in its general form the L. mrtiloides of
the Coal Measures, but differs from that in its uniformly much
larger size and relative proportions.

Hare, and hitherto found only in the Warsaw beds of the St.
Louis group at Warsaw and near Hamilton, 111.

Collector. A. H. Wort hen.

No. 2495 of the Illinois State Museum.

GENUS SPIKIFEKA. Sowerby.
SPIHIFERA MLXTIGRAXOSA. (sp. nov.)

PL XI, Figs. 5-oa, 5b.

Shell of medium size, ventral valve strongly convex, length a
little more than the width: hinge line about equal in length to
the greatest width of the valve. Beak strongly arched, and re-
curved beyond the cardinal area.

A profound sinus commences at the beak, and gradually widens
and deepens to the frontal border where it occupies about one-
third of the entire width of the valve. There are two rather
obscure costte on each side of the sinus, one of which extends
nearly to the beak, while the other becomes obsolete about half
way from the frontal margin to the beak. On each side of the
sinus there are from 8 to 10 unequal sized rounded plications
that are wider than the intervening spaces. Cardinal area
moderately wide.

Dorsal valve less convex than the ventral, beak depressed, in-
curved, and not projecting beyond the hinge line, area narrow.
A strong mesial fold commences at the beak with a rather broad
flat cost a. having a central depression that continues to the
frontal margin. On each side of this there is an obscure costa,
that becomes obsolete before reaching the beak. The two first
plications on each side of the mesial fold are much stronger
than those on the lateral borders. The entire surface of the

shell is thickly set with small granules.
-13

106 PALAEONTOLOGY OF ILLINOIS.

Position and locality: Coal measures, Rolls Ford, Sangamon
county.

Collector, A. H. Worthen.
No. 2597 of the Illinois State Museum.

GENUS ORTHIS. Dalman.

;

ORTHIS RESUPINOIDES. Cox.

PI. XI, Figs. 4-4a,4b.

Shell transversely ovate to subquadrate in outline, hinge line
straight, and scarcely more than half as long as the greatest
breadth of the shell; cardinal angles rounded, cardinal area
narrow, and widest on the dorsal valve.

Dorsal valve depressed, convex towards the beak, and strongly
depressed at the front, giving a sinuous outline to the frontal
margin.

Ventral valve convex, the greatest convexity rather nearer
the beak than the front. Beaks depressed, incurved, and pro-
jecting slightly beyond the hinge line.

Surface of the valves marked by numerous fine thread-like
stride, and several transverse lines of groAvth.

This shell is so closely allied to Martin's species, O. rexupinata,,
that it can hardly be regarded as specifically distinct. The only
external differences observable, on a comparison of the American
with authentic examples of the European shell are, the compara-
tively shorter hinge line and somewhat finer striae of the Ameri-
can shell.

Position and locality: Lower Coal Measures, Mercer county,
Illinois.

Collector, Tyler McWhorter, Esq.

No. 2600 of the Illinois State Museum.

INVERTEBRATES, 107

LAMELLIBRANCHIATA.

GENUS LEPTODOMUS. McCoy.
LEPTODOMIS? MAI;. NTS. Worthen.

PI. XYIII, Fig. 2.

Schizodus magnus, Worthen. March, 1884, Bulletin No. 2, of the Illinois State Museum of

Natural History, page 9.

Shell large, ovate sub-quadrangular, convex, the greatest con-
vexity being about half-way from the beaks to the ventral mar-
gin; anterior extremity comparatively long and broadly rounded,
posterior side about once and a half the length of the anterior,
obliquely flattened behind the beaks with a well defined umbonal
ridge extending diagonally from the beak to the posterior ex-
tremity of the ventral margin. Dorsal margin straight from
the beaks to the obliquely truncated posterior margin.

Beaks long, strongly recurved, and projecting about % of an
inch beyond the dorsal margin.

Length 7/i6 inches; height 2%6 inches; convexity of the valve
about % inch.

This is from one of the upper divisions of the Chester lime-
stone, about two miles below the mouth of Mary's river, Ran-
dolph county; 111.

Collector, A. H. Worthen.

No. 2498 of the Illinois State Museum.

GENUS SCHIZODUS. King.
SCHIZODUS VARSOVIENSIS. Worthen.

PL XIX, Fig. 7.

Schizodus varsoviensis, Worthen, March, 1884. Bulletin No. 2, of the Illinois State
Museum of Natural History, page 10.

Shell of medium size, transversely ovate, moderately convex
in the anterior and umbonal regions, cuneate posteriorly ; anter-

108 PAL/EONTOLOGY OF ILLINOIS,

ior side very short and regularly rounded; basal margin form-
ing a very gentle curve that is most prominent near the anterior
margin; posterior extremity contracted and narrowly rounded;
dorsal margin nearly straight, beaks 'depressed, incurved and
located about one-third the length of the shell from the anterior
margin. Surface markings unknown.

Length of an internal cast in limestone 1% inches; height of
same % inch, convexity about % inch.

This species may be readily distinguished from S. cliesterpnsis,
which it approaches in size and form, by its relative proportions
and more depressed beaks.

Position and locality: The upper part of the Keokuk lime-
stone, Warsaw, 111.

Collector, A. H. Worthen.

No. 2500 of the Illinois State Museum.

SCHIZODTJS NAUVOOENSIS. WortllPll.

PL XX, Fig. 3.

Schizodiis nauvooensis, Worthen, Match, 1884. Bulletin No. 2, of the Illinois State
Museum of Natural History, page 10.

This shell is only known from a cast of a single valve in lime-
stone, but it differs so decidedly from all others of this genus,
that it may be readily characterized as follows:

Shell above the medium size, obliquely sub-ovate, rather
strongly convex from the beak obliquely downward for about
half the length of the valve, and thence gradually depressed to
the ventral margin, anterior extremity regularly rounded from
the dorsal to the ventral margin, posterior side oblique, the
marginal line curving in below the beak; ventral margin not
entire, beak pointed, elevated and incurved, and situated near
the anterior margin, surface markings unknown. A well-defined
ovate muscular scar is conspicuous just below the beak, and
near the anterior border of the shell.

Length from the beak to the ventral margin measuring obli-
quely, 2 inches; greatest breadth !•% inches.

Position and locality: Keokuk limestone, Nauvoo, 111.

Collector, A. H. Worthen.

No. 2499 of the Illinois State Museum.

[OTERTEBRATE8. 109

SCHIZODUS DEPRESS!-*. Worthen.

PI. XVIII, Fig*. S-«a.

Schizodus depresses, Worthen, March. 18&4. Bulletin No. 2. of the Illinois State Museum
of Natural History, page II.

Shell below the medium size, transversely ovate, .slightly con-
vex, beak depressed, posterior extremity cuneate, anterior ex-
tremity regularly rounded into the semi-ovate curve of the basal
region. Posterior side a little longer than the anterior, and
rather sharply rounded at the extremity : dorsal margin rapidly
sloping towards the anterior extremity; surface smooth.

Length of an average size specimen 9/16 inch; height from
beak to basal margin " li; inch: convexity of the valves about
% inch.

This species may be readily distinguished from all previously
described species by its generally depressed form.

Position and locality: Oolitic beds of the St. Louis group,
Monroe county, 111.

Collector, A. H. Worthen.

No. 2520 of the Illinois State Museum.

Si Hizoors? ciRruLrs. Wort hen.

PI. XIX. Fig. 1.

circulus. Worthen. March, 1884. Bulletin No. 2, of the Illinois State Museum
of Natural History, page 11.

Ill the collection from the oolitic beds of Monroe county, there
are three or four detached valves of a small shell, that are doubt-
fully referred to the genus Scbizodus, and which may be charac-
terized as follows:

Shell small, nearly circular in outline, slightly inequilateral,
valves slightly convex, beaks depressed, and extending slightly
beyond the cardinal border. A very slight umbonal ridge is
apparent on some of the specimens that becomes obsolete before
reaching the basal margin. Surface smooth. Height from beak
to base "/•,« inch: length % inch.

This shell resembles the form figured and described by Prof.
M'-i'uy in his "Synopsis of the Garb. Fossils of Ireland," PI. XI,
fig. 13, but is much more nearly circular than his Dolabra orbi-
cnlaris.

110 PALAEONTOLOGY OF ILLINOIS.

Position and locality: Oolitic beds of the St. Louis group,
Monroe county, 111.
Collector, A. H. Worthen.
No. 2521 of the Illinois State Museum.

SCHIZODUS ULRICHI. (sp. 11OV.)
PL XXI. Figs. 1-la. Ib. PL XX. Fig. 9.

Shell above a medium size, ovate, valves moderately com-
pressed; beaks strongly incurved forward, and situated a little
less than one-half the length of the shell from the anterior mar-
gin. Anterior border evenly rounded up from the basal margin
to the beaks. Hinge line short ; basal margin rather long, and
gently curving behind to the rather narrow posterior extrem-
ity. Lunule clearly denned, but not deep. A slightly elevated
umbonal ridge extends from the beaks to the posterior extrem-
ity. Surface smooth except some faint lines of growth near
the basal margin.

Anterior adductor muscular scar nearly circular, and situated
about half way from the beak to the base of the anterior mar-
gin; posterior muscular scar not so well defined, and situated
about equi-distant from the beaks to the posterior extremity.

Length of a specimen of average size, l9/ie inches; breadth
from the beaks to the cardinal border 1% inches ; thickness with
the valves united 1 inch.

This shell has been confounded with S. wheeleri, Swallow sp.
but differs from that shell as usually figured in its larger size,
depressed umbonal slopes and ovate outline.

Position and locality : Upper Coal Measures, Fairfield, Wayne
county, Illinois.

No. 2584 of the Illinois State Museum.

SCHIZODUS RANDOLPHENSIS. (sp. nOV.)
PL XX, Fig. 12.

Shell elongate ovate, truncated at the anterior extremity and
narrowly rounded behind. Beak depressed, projecting beyond
the hinge line, and situated close to the anterior extremity.

INVERTEBRATES. Ill

Hinge line about two-thirds as long as the valve with a wide
cardinal area nearly equaling it in length. Basal area regularly
curved from the truncated anterior margin to the posterior ex-
tremity.

Anterior muscular scar, situated close to the anterior extrem-
ity, and about midway from the beak to the basal margin.
Dorsal scar about twice as large a.s the anterior one, and
located midway between the beak and the posterior extremity.

Surface markings unknown.

Length 2% inches: height about 1* 1H inches.
Position and locality: Chester limestone, Chester, 111.
Collector, A. H. Wort hen.
No. 2590 of the Illinois Sun.- Museum.

GENUS PINNA, Linnaeus.
PINNA SAN< TI-LVDOVICI. Worthen.

PL XIX, Fig. 6.
Pinna St. Ludorici Worthen, 1883. GeoL Survey of Illinois Vol. VII, page 336.

Shell comparatively short, lanceolate; length about twice MS
much as the greatest width. Section ovate-elliptical, valves
traversed longitudinally by about twelve to fifteen rather strong
ribs that are most prominent on the middle portion of the shell,
and become obsolete towards the ventral and dorsal margins.
Spaces between the ribs narrow, beak unknown. Angle formed
by the dorsal and ventral margins about 40°.

This rare species is only known from a single specimen pre-
served in chert, with both extremities wanting. It may be
readily distinguished from P. inisfiouriensix. of the Chester lime-
stone, and from any other species known in our carboniferous
rocks, by its shorter form and greater proportional width.

Position and locality: St. Louis limestone. Monroe county,
Illinois.

Collector, H. F. Henckler.

No. 2490 of the Illinois State Museum.

112 PALAEONTOLOGY OF ILLINOIS.

GENUS CONOCARDIUM. Bronn.

CONOOARDIUM PARRISHI. (sp. DOV.)
PI. XX, Fig. 7.

Shell obliquely triangular, hinge line straight, beaks depressed
umbonal ridge elevated into a strong rounded fold with faint
traces of fine striae towards the lower extremity. Anterior side
evenly and rapidly sloping from the umbonal fold to the ex-
tremity, and traversed by radiating costae only four or five of
which extend to the hinge line, but increasing by division and
implantation so that ten or more may be counted on the mar-
gin of the shell, the one nearest the umbonal ridge being some-
what stronger than the others.

Posterior side flattened towards the extremity, and marked
by eight or more flattened striae nearly all of which extend to
the hinge line.

Length about 5/i« inch.

Position and locality: Oolitic limestone of the upper Coal
Measures near Kansas City, Mo.

Collector, W. J. Parrish, of Leavenworth, Kansas, to whom
we have dedicated the species.

No. 2605 of the Illinois State Museum.

GENUS AVICULOPECTEN. McCoy.

AVICULOPECTEN ORESTES. Wortlieil.
PI. XXII, Fig. 6.

Aviculojirftcn (irt'xtea Worthen, March, 1884, Bulletin No. 2 of the Illinois State Museum
of Natural Hislory, page 18.

Shell below the medium size, equilateral, broadly ovate when
divested of the ears; hinge line about equal to the greatest
breadth of the shell ; ears of moderate size and smooth or
showing only faint lines of growth; lateral sides diverging for
a short distance below the ears, and then broadly rounded into
the basal border.

Surface ornamented with about 18 to 20 even, stout, rounded
ribs or costae, that are about twice as wide as the intervening
spaces.

INVERTEBRATES. 113

Length from beak to base 15/16 inch; breadth 1 inch; length
of hinge line about % inch. This shell may be readily distin-
guished from otlu-i-.- <>r.urring in the same horizon by its broad
rounded cost*.

Named in honor of my Mend Prof. Orestes St. John, of Topeka,

Kan-

Position and locality: Keokuk limestone, Warsaw, 111.

Collector, A. H. Worthen.

No. 2504 of the Illinois State Museum.

A vii TLOPECTEN NiOTENSis. Worthen.

PL XXH. Fig. 10.

Acteidopecten niotense Worthen, March, 18&4, Bulletin No. 2, of the Illinois State Museum
of Natural History, page 19.

Shell large, orbicular, nearly or quite equilateral, length and
breadth about equal, hinge line shorter than the greatest width
of the shell. Left valve moderately convex, basal margin
broadly and evenly rounded, anterior ear short, triangular, and
separated from the lateral margin by a well-defined sinus. Pos-
terior ear more than twice as long as the anterior, and pointed
at the extremity. Surface of the valve ornamented with numer-
ous fine radiating cost*?, of which about fourteen may be
counted near the basal margin in the space of half an inch.
These cost* appear to become obsolete on the ears and on the
lateral borders of the shell.

Length 2;\ inches; breadth about the same; length of hinge
line about 2 inches.

This shell may be readily distinguished from the .1. vansovi-
ensis. described and figured in Vol. VII of these reports, by the
much finer radiating cost* with which it is ornamented.

Position and locality: Keokuk limestone, Niota, Hancock
county, Illinois.

Collector, A. H. Worthen.

No. 2505 of the Illinois State Museum.

114 PALAEONTOLOGY OF ILLINOIS.

AVICULOPECTEN MONROENSIS. Worthen.

PI. XXII, Fig. 8-8a.

Aviculopecten monroensis Worthen, March, 1884, Bulletin No. 2 of the Illinois State
Museum of Natural History, page 21.

Shell below the medium size, left valve moderately convex,
sub-ovate or nearly circular below the ears, the lateral borders
gradually rounding into the broadly rounded basal margin.
Ears nearly equal in size and ornamented with five or six rad-
iating costse similar to, and continuous with those on the body
of the shell, and also with delicate concentric lines that are
plainly visible under an ordinary lens. Surface of the valve or-
namented with 60 to 70 irregular sized rounded costae that are
usually a little wider than the intervening spaces, and fine
transverse striaa similar to those on the ears, which are only
visible under a lens. A right valve belonging apparently to
this species is nearly flat, radiating costa? very fine, anterior
ear longer than the other and defined by a deep narrow sulcus,
and both ornamented with costse and concentric striae that are
a litttle less conspicuous than those on the opposite valve.

Length of left valve 1:1/16 inch; breadth about the same;
length of hinge line °/16 inch.

Position and locality: Oolitic beds of the St. Louis group,
Monroe county, 111.

Collector, A. H. Worthen.

No. 2509 of the Illinois State Museum.

AVICULOPECTEN TALBOTI. Worthen.

PI. XXII, Fig, 11-lla.

Aviculopecten talboti Worthen, March, 1884. Bulletin No. 2 of the Illinois State
Museum of Natural History, page 21.

Associated with the A. monroensis, there is a smaller form
that seems to be clearly distinct, and may be characterized as
follows :

Shell small, broadly ovate in outline, left valve moderately
convex, ears short and not well defined from the lateral bor-
ders. Surface apparently smooth, but under a good lens min-
ute radiating and concentric lines may be seen, which are most
conspicuous on the ears and lateral borders of the shell.

INVERTEBRATES. 115

Length of the largest individual seen % inch ; breadth about
the same: length of hinge line about % of an inch. This form
differs from the A. monroenxix in its smaller size and nearly
smooth surface. Named in honor of my friend Henry Talbot,
Ksq.. of Waterloo.

Position and locality: Same as the last.

Collector. A. H. Wort hen.

No. 2510 of the Illinois State Museum.

AvirrLopErTEN ELSAHE.vsis. "Worthen.

PL XXII, Fig. 3.

Aviculovecteii rlfahpnsit, Worthen, March, 18*4. Bulletin No. 2 of the Illinois State
Museum of Natural History, page 19.

Shell of medium size, left valve moderately convex, and ex-
clusive of the pars presenting a slightly oblique sub-trigonal
outline: hinge line equaling about two-thirds the greatest width
of the valve: basal outline forming a somewhat oblique semi-
circular curve; posterior margin straight from the base of the
ear to the basal curve where the valve attains its greatest width.
Anterior margin regularly rounded; anterior ear small and ob-
tusely angular: posterior ear large, triangular, and sharply
pointed at the extremity. Surface of the ears apparently with-
out ornamentation. Surface of the shell ornamented with nu-
merous radiating cost.e that increase by implantation, and are
somewhat variable in size, being usually about equal to the in-
tervening Spaces.

Length I1" u- inches: breadth I11/™ inches: length of hinge
line I1* inches.

Position and locality: Kiuderhook group? half a mile above
Elsah. Jersey county. 111.

Collector. A. H. Worthen.

No. 2506 of the Illinois State Museum.

AvifTLOPEtTEN CHESTEREXSIS. Woi'theU.
PI. XXI, Pig. 5-Sa.

Aviculopecten chesterensis, Worthen, March, 1884. Bulletin No. 2 of the Illinois State
Museum of Natural History, page 20.

Shell above the medium size, nearly equilateral, broadly ovate
or semi-circular in outline, a little wider than long; left valve
moderately convex, beak depressed and extending slightly be-

116 PALEONTOLOGY OF ILLINOIS.

yond the cardinal border. Anterior ear broken away, posterior
ear small and ornamented with fine lines of growths. Surface
of the valve ornamented with 36 to 40 radiating unequal-sized
costae the alternating ones nearly twice as wide as the others,
and all traversed for more than half their length by smaller
costoe which become obsolete before reaching the cardinal bor-
der. Traces of numerous transverse striae are also visible where
the surface of the shell is well preserved.

Length 2% inches; breadth 2% inches.

This shell is closely allied to A. provifk'iisis, Cox, sp. from
the Coal Measures of Kentucky, but differs from that in its
smaller and more numerous costap and transverse striae.

Position and locality: Lower division of the Chester lime-
stone, Chester, 111.

Collector, Mrs. J. C. Salter.

No. 2507 of the Illinois State Museum.

AVICULOPECTEN SPINULIFERUS. Meek and Worthen.

Pf XXII. Pig. 1.

Aviculopecten spinuli ferns , Meek and Worthen. 1870, Pro. of the Acad. of Nat. Sc., Phila.,
and Bulletin No. 2 of the Illinois State Museum of Natural History, page 20.

Shell of medium size, inequilateral, obliquely ovate; left valve
moderately convex, and ornamented with about fify angular
spiuuliferous costoe, each alternate one being about twice as large
as the others, the small ones coalescing with the large ones
before reaching the cardinal border. Beak moderately elevated,
and located about one-third nearer the anterior than the pos-
terior termination of the hinge line. Anterior ear sharply tri-
angular, about half as large as the posterior, and ornamented
with three or more spiniferous costae similar to those on the
body of the shell. Posterior ear large and not clearly defined
from the lateral border, the spiuiferous costae extending without
interruption to the cardinal border. Anterior lateral border
neatly rounded from the sinus below the ear to the ventral border.

Length measuring obliquely from the beak to the basal mar-
gin l^/io inches; breadth 1% inches; length of hinge line 1%
inches; posterior ear 15/le inch; anterior ear J1/1(. inch. Right
valve unknown.

Position and locality: Keokuk shale, Crawfordsville, Indiana.

Collector, Frank H. Bradley.

No. 2508 of the Illinois State Museum.

INVERTEBRATES. 117

AVICULOPECTEN MAZONENSIS. (sp. nOV.)
PL XXII. Pig. 9.

Shell rather below medium size, ovate, slightty inequilateral;
left valve moderately convex, the greatest convexity being about
2/5 the distance from the hinge line to the cardinal border.

Hinge line straight, beak depressed, extending slightly bej^ond
the hinge line, and situated a little forward of the middle.
Ears nearly equal in size, triangular, and marked by about
eight radiating costie, much smaller than those on the body of
the shell. Anterior lateral border regularly rounded from the
base of the~anterior ear to the cardinal border.

Cardinal border regularly rounded; posterior lateral border
nearly straight from the base of the posterior ear to the point
where it joins the rounded cardinal border.

Surface of the left valve ornamented with about thirty rounded
costae on the cardinal border, which on the middle of the shell
are about as wide as the intervening spaces, but unequal in
size. A portion of the cost* becomes obsolete before reaching
the hinge line.

Length of a large individual l6/ie inches; breadth about the
same; length of hinge line 1 inch.

Position and locality: Coal Measures, Mazon creek, Grundy
county, 111.

No. 2952 of the Illinois State Museum.

AVICULOPECTEN HARDINENSIS. (sp. nov.)

PI. XXII, Figs. 5-5a.

Shell of medium size, obliquely ovate in form, the length ex-
ceeding by about one-tenth the lateral diameter. Basal and
lateral margins regularly rounded.

Left valve moderately convex, beak obtuse, hinge line straight,
and equal in length to about four-fifths of the greatest lateral
diameter. Anterior ear rather narrow, triangular, and sharply
defined from the lateral border. Posterior ear broken away.

Test thin and ornamented with longitudinal rays of which
about four to five may be counted on the basal border in the
space of one-fourth of an inch. The longitudinal rays are

118 PALEONTOLOGY OF ILLINOIS.

crossed by rounded stria* about half the diameter of the rays,
giving a strong reticulated character to the surface where the
test is well preserved.

Length 2% in., greatest breadth 2% inch., length of hinge line
about 1% infix's.

Position and locality: St. Louis limestone, Hardin county,
Illinois.

Collector, A. H. Worthen.

No. 2951 of the Illinois State Museum.

AVICULOPECTEN MAC-VVHORTERI. (sp. nOV.)
PI. XXII, Fig. 4.

Shell of medium size, inequilateral; obliquely sub-circular in
outline, a little broader than long; hinge line about equal to
the greatest breadth of the shell.

Left valve moderately convex, in the umbonal region, and
flattened towards the lateral and basal borders. Anterior ear
narrow, and clearly defined: posterior ear broader, and not
clearly defined from the postero-lateral border, and both orna-
mented with rounded striae, similar to those on the body of the
shell.

Surface of the valve ornamented with about sixty to sixty-four
rounded striae, each alternate one smaller than the others, and
becoming obsolete about half way from the basal margin to the
hinge line.

Length 1% inches, greatest breadth 111/10 inches.

Position and locality: Kinderhook group, Kinderhook, Pike
county, 111.

Dedicated to Tyler McWhorter, Esq., of Aledo, Mercer county,
111., in consideration of his meritorious services as an industrious
collector of western fossils.

Collector, A. H. Worthen.

No. 2583 of the Illinois State Museum.

INVERTEBRATES. 119

AVICTJLOPECTEN coLLETTi. AVorthen.

PI. XXII, Figs. 13 and 8b.

Arii-iii<jpecten coUetti, Worthen. March, 1884. Bulletin No. 2, of the Illinois State Museum
of Natural History, page 22.

Shell below the medium size, inequilateral, ovate. Left valve
slightly convex, ears well defined and unequal in size. Anterior
ear small, triangular, posterior ear rather larger than the
anterior, ornamented with four or five longitudinal costse and
fine transverse lines of growth, with a well defined notch at its
junction with the lateral border. Lateral borders straight nearly
to the middle of the valve and thence rounding into the ventral
border.

Surface of the valve ornamented with 35 to 40 slightly convex
radiating cost* which increase in size towards the free borders
of the shell.

Right valve nearly flat, ears rather more prominent than on
the opposite valve, and radiating costae less distinct. Length
from the beak to the ventral margin % inch; greatest breadth
11 1(i inch; length of hinge line, % inch.

.Vanied in honor of Prof. John Collett, the able State Geolo-
gist of Indiana.

Position and locality : From the shaly beds of the Keokuk
group, fYawfordsville, Indiana.

Collector, Frank H. Bradley.

No. 2512 of the Illinois State Museum.

A VICULOPECTEN EDWARDSi. Worthen.

PI. XXII, Fig. 2.

Aviculopecten edwardsi, Worthen, March, 1884. Bulletin No. 2, of the Illinois State
Museum of Natural History, page 22.

Shell of medium size, obliquely ovate, right valve very convex,
breadth a little more than the length ; anterior ear rather large,
triangular, posterior oar not preserved ; posterior border oblique,
and extending in a nearly straight line from the beak to the
basal margin; anterior border moderately rounded from the ear
to the basal margin.

Surface of the valve ornamented with ten or twelve rather
sharp prominent costce,"with two or three indistinct ones in the
intervening spaces on the lower portion of the shell.

120 PALAEONTOLOGY OF ILLINOIS.

Length from beak to base 1 3/16 inches ; greatest breadth !5/i6
inches; length of anterior ear %« inch.

Position and locality : From the upper division of the Keokuk
limestone, Warsaw, 111.

Collector, A. H. Worthen.

No. 2511 of the Illinois State Museum.

AVICULOPECTEN MENARDi. Worthen,

PL XXII. Fig. 12.

Lima? menardi, Worthen, March, 1884. Bulletin No. 2, of the Illinois State Museum of

Natural History, page 22.

Shell small, thin, obliquely ovate, very inequilateral ; ears small,
nearly equal in size, triangular; hinge line straight, and about
half as long as the greatest width of the shell. Right valve
nearly flat; anterior side projecting forward, with a nearly
straight margin to the regular curve of the basal margin; pos-
terior side shorter than the anterior, and rounding up from the
basal margin nearly to the ear, where it makes a slight back-
ward curve, forming a slight sinus just below the ear.

Surface marked by numerous transverse stria?, that extend
from the hinge line quite around the borders of the shell, cover-
ing apparently its entire surface. Left valve unknown.

Length from the hinge line to the basal margin, % inch ; great-
est breadth about the same; length of the hinge line % inch.

The only specimen of this pretty shell in the State collection,
was obtained from the bituminous shale forming the roof of the
Greenview coal in Menard county.

Collector, A. H. Worthen.

No. 2513 of the Illinois State Museum.

GENUS LIMA, Bruguiere.
LIMA CHESTERENSIS. (sp. nov.)

PI. XXII, Fig. 7. '

A single valve of a shell belonging apparently to the genus
Lima was obtained by the Avriter from a thin layer of ferru-
ginous limestone intercalated in the shales which separate the
main limestones at Chester. The specimen represents the right
valve with the posterior ear broken away.

INVERTEBRATES. 121

This genus has not hitherto been recognized so far as known
to the writer in strata below the Coal Measures in this country,
but in Europe it has been found in Lower Carboniferous strata,
and two specjes have been described and figured by Prof. L. G.
de Kouiuck from the Carboniferous limestones of Belgium.

Description: Shell of medium si/e. ovate, umbones depress* •• 1 .
valves moderately convex, the greatest convexity being some-
what nearer the hinge line than the basal margin. Hinge line
straight, and about two-thirds as long as the antero-posterior
diameter of the valves. Posterior side shorter than the anterior
and gradually rounded from the hinge line to the basal margin.

Surface ornamented with 28 to 30 rounded striie. each alter-
nate one being smaller than the others, and extending only
about half way to the hinge line.

Height 1:j ]f. inch: breadth % inch; length of hinge line 7/i6
inch.

Position and locality: Chester shale, Chester, 111.
Collector. A. H. Worthen.
No. 2593 of the Illinois State Museum.

GENUS EDMONDIA, DeKoninck.
EDMONDIA VARSOVIKNSIS. Worthen.

PL XX, Figs. 11-lla.

Edmondia varsovienses, Worthen, March, 18&4. Bulletin No. 2 of the Illinois State

of Natural History, page 18.

Shell above the medium size, compressed ,-uid evenly rounded
at the extremities; length about one-third greater than the
height: basal margin broadly semi-ovate in outline, dorsal mar-
gin sloping abruptly from the beaks in front, and nearly straight
behind for about two-thirds the entire length of the shell, and
thence rounding into the posterior margin: beaks depressed and
located near the anterior extremity.

The surface of the cast shows traces of delicate closely ar-
ranged concentric stria*, and a few more distinct lines of growth.

Length of the typical specimen 2's inches: height 1% inches.
This shell is only known from limestone cae
—15

122 PALEONTOLOGY OF ILLINOIS.

Position and locality: From the upper part of the Keokuk
limestone, Warsaw, 111.
Collector, A. H. Worthen.
No. 2502 of the Illinois State Museum.

EDMONDIA ILLINOIENSIS. Worthen.

PL XVIII. Figs. 7-7a.

Edmondia UUnoiensis, Worthen, March, 1884. Bulletin No. 2 of the Illinois Slate Mus-
eum of Natural History, page IN.

Shell of medium size, transversely sub-oval, convex, broadly
rounded at the extremities; dorsal margin straight behind the
beak for a.bout two-thirds its length, and thence rounding into
the posterior border; basal margin slightly sub-ovate; beak de-
pressed and located about one-third the entire length of the
shell from the anterior extremity. Surface of the cast marked
by distinct parallel lines of growth.

Length 1% inches; height lVi« inches; convexity of the valves

about 5/i6 mcn-

This is a smaller and more convex shell than the preceding
species, and shows none of the fine concentric stria? that appear
on the E. vaiKoviennix.

Position and locality: Same as the preceding species.

Collector, A. H. Worthen.

No. 2503 of the Illinois State Museum.

CLINOPISTHA KADIATA. Hall, sp.

PI. XIX, Fig. 3, and PI. XXI, Fig. 2.

Shell elongate oval, height rather less than two-thirds the en
tire length; valves moderately convex; posterior extremity
truncated, anterior rounded; hinge line straight and equaling
about one-half the entire length of the shell.

Beaks depressed and incurved posteriorly. Ventral margin
slightly sinuate near the posterior extremity, and sub-parallel
with the dorsal.

Surface ornamented with obscure lines of growth and numer-
ous radiating stria? that cross the shell diagonally from the
beaks to the anterior and ventral margins.

Length l°/]6 inches; height Ir>/,(! inch; thickness n/i(5 inch.

Position and locality: Coal measures, Mercer county, 111.

Collector, Tyler McWhorter, I0s<|.

No. 2586 of the Illinois State Museum.

INVERTEBRATES. 123

GENUS MACRODON, Lycett.
MACRODON SANGAMONENSIS. (sp. nov.)

PL XXI, Figs. 3-3a.

Shell large, transversely elongated, hinge line equal to about
4/s of the entire length of the shell.

Posterior margin compressed and obliquely truncated, so as
to meet the hinge line at a rather acute angle; posterior ex-
tremity quite narrow, and rounding gently downward to the
basal margin.

Anterior margin regularly rounded from the anterior extrem-
ity to the basal margin, which is slightly sinuous about the
middle.

Beak depressed, strongly incurved, and placed about one-fifth
the length of the hinge line from the anterior extremity.

A gradually widening depression extends from the beaks to
the posterior extremity on the dorsal margin, and on this flat-
tened portion six or seven strong striae may be seen, which ex-
tend from the beak to the posterior extremity. Strong lines of
growth extend around the basal margin, and minute transverse
striae are visible under a lens, especially on the anterior portion
of the shell.

Length 2% inches; length of hinge 1% inches: height 15/1(. inch;
convexity of valves 7/l6 inch.

Position and locality: Coal Measures, Rolls Ford, Sangamon
county, 111.

Collector, A. H. Worthen.

No. 2585 of the Illinois State Museum.

GENUS PLEUROPHORITS, King.
PLEUROPHCRUS CHESTERENSIS. Worthen.

ri. XX, Fig. C.

Pteurophoma chesterensis, Worthen, March, 1884. Bulletin No. 2 of the Illinois State
Museum of Natural History, page 16.

Shell of medium size, nearly cylindrical when the valves are
closed, almost three times as long as high, most strongly con-
vex on the anterior half of tlic shell; cardinal margin straight

124 PAL/EONTOLOGY OF ILLINOIS.

and about equaling three-fourths the entire length of the valves;
basal margin slightly sinuous near the middle; anterior ex-
tremity broadly rounded and wider than the posterior; beaks
depressed and located very near the anterior extremity. An
ill-defined radiating ridge extends from behind the beaks
obliquely to the posterior margin, between which and the car-
dinal margin some indistinct traces of longitudinal costa1 may
be seen.

The specimen is a cast in limestone of both valves slightly
displaced. Minute surface markings unknown.

Length 19/10 inches, height from beak to base % inch.

Position and locality: Chester limestone, Chester, 111.

Collector, A. H. Worthen.

No. 2501 of the Illinois State Museum.

PLEUROPHORUS MINIMUS. Worthen.

PI. XX, Figs. 4-4a.

Pleurophorun minimus, Worthen, March, 1884. Bulletin No. 2 of the Illinois State
Museum of Natural History, page 17.

Shell small, about twice as long as high, moderately convex.
Outline elongate ovate. Anterior margin slightly produced
forming an obtuse point, posterior margin obliquely truncated ;
dorsal and ventral margins nearly straight and sub-parallel,
the latter rounding up to the obtuse anterior extremity. Beaks
depressed, and placed about one-fourth the length of the valve
behind the anterior extremity.

Posterior umbonal slopes sub-angular from the beaks obliquely
backward and downwa-rd to the posterior extremity, with a
decided depression between their slopes and the cardinal mar-
gin. Surface marked by linear lines of growth, crossed by rad-
iating costs?, which are most strongly defined on the depression
of the cardinal area, and on the posterior portion of the shell.

Length 5/16 inch ; height % inch; convexity of the valves about
Vie incn-

Position and locality: Oolitic beds of the St. Louis limestone,
Monroe county, Illinois.

Collector, A. H. Worthen.

No. 2524 of the Illinois State Museum.

INVERTEBRATES. 125

PL,ETJROPHORUS MONROENSIS. Worthen.

PI. XVIII, Fig. 3-3a.

Pleurophorus monroensis, Worthen, Marsh, 1884. Bulletin No. 2, of the Illinois State
Museum of Natural History, page 17.

Shell elongate-oblong, moderate!}' convex ; umbonal ridges
forming- the most convex part of the valves ; length about twice
as much as the height ; a well-defined ridge commencing at the
beak extends diagonally to the posterior extremity; anterior
ventral region depressed ; cardinal margin straight, and rather
more than half the entire length of the shell; basal margin
nearly straight in the middle, but rounding up in front to the
anterior extremity : beaks depressed to the hinge line, and
placed about one-fourth the length of the shell behind the an-
terior extremity, surface smooth.

Length % inch; height % inch; convexity about % inch.

Position and locality : Oolitic beds of the St. Louis group,
Monroe county, 111.

Collector. A. H. Worthen.

No. 2523 of the Illinois State Museum.

GENUS MODIOLA, Lamarck.
MODIOLA ILLINOIEXSIS. Worthen.

PL XX, Fig. 2-2a.

Modiola HUnoirnsis, Worthen, March, 1884. Bulletin No. 2 of the Illinois State Museum
ot Natural History, page 16.

Shell below medium size, length from the anterior to the pos-
terior extremities a little more than twice the width of the
valves, narrowing rather rapidly behind the posterior extremity
of the hinge line; valves strongly convex in the umbonal region,
and obliquely across the valve to the ventral margin, com-
pressed behind; beaks depressed, hinge line equal to three-fifths
the entire length. A shallow depression extends from the beak
obliquely to the ventral margin in front of the umbonal ridge
posterior margin narrowly rounded, anterior extremity obtusely
pointed, ventral margin slightly sinuate in the middle, hinge
line straight, surface nearly smooth but showing a few obscure
lines of growth.

126 PALEONTOLOGY OF ILLINOIS.

Length of an average size specimen ir>/i« inch; breadth at the
posterior extremity of the hinge line 7/i« inch; convexity of the
valve about 3/1(, inch.

Position and locality : From the oolitic beds of the St. Louis
group, Monroe county, 111.

Collector, A. H. Worthen.

No. 2518 of the Illinois State Museum.

GENUS CARDIOMORPHA, DeKoninck.
CARDIOMORPHA? PELLENSIS. Worthen.

PI. XIX, Figs. 9-9a, 9b.

Cardiomorpha pellaensis, Worthen, March, 1884. Bulletin No. 2 of the Illinois State
Museum of Natural History, page Hi.

Shell longitudinally sub-ovate, length less than once and a
half the height; dorsal and ventral borders sub-parallel, dorsal
margin nearly straight, ventral margin moderately curved ;
valves convex, the greatest convexity being about one-third the
distance from the beaks to the ventral margin ; beaks depressed
and placed close to the anterior extremity which is nearly straight
above, and curving below into the ventral margin; posterior
extremity cuneate.

The specimen is a cast in a calcareous shale, and shows no
surface ornamentation.

Length 11/le inch; height 7/i« inch; thickness 5/16 inch.

Position and locality : Shaly limestone of the St. Louis group,
Pella, Iowa.

Collector, A. H. Worthen.

No. 2516 of the Illinois State Museum.

GENUS BAKEVELLIA, King.
BAKEVELLIA ILLINOIENSIS. Worthen.

PI. XVIII, Fig. 4-4a.

Bakevellia ittinoiensis, Worthen, March. 1884. Bulletin No. 2 of the Illinois State Museum
of Natural History, page 14.

Shell about medium size, elongate sub-rhomboidal, left valve
moderately convex from a ridge which extends from the beak
about two-thirds the distance to the cardinal border where it
becomes obsolete.

INVERTEBRATES. 127

This ridge slopes abruptly to the dorsal margin, and more
gradually to the anterior portion of the shell. Posterior wing
equal to about two-fifths of the entire length of the shell. Um-
boiial region squarely truncated at the apex, upper portion of
the anterior margin nearly straight to the point where it joins
the ventral portion of the valve, or about one-fourth its entire
length. Surface ornamented with numerous concentric lines of
growth, which are closely arranged on the umbo, but become
more widely spaced on the lower margins of the shell. Right
valve unknown.

Length 1'x inches: greatest breadth about % inch; convexity
of left valve % inch.

Position and locality: Upper Coal Measures, LaSalle, 111.

Collector, A. H. Wort hen.

No. 2525 of the Illinois State Museum.

GEMS MYALINA, DeKoninck.
MYALINA MONKOENSIS. Worthen.

PL XX, Figs. 10-lOa.

Myalina monroensis, Worthen, March, 18*1. Bulletin No. 2, of the Illinois State Museum
of Natural History, page 15.

Shell small, nearly equi valve, moderately convex on the um-
bonal slopes from the beaks two-thirds the distance to the
posterior extremity, becoming gradually depressed below. Pos-
terior and postero-lateral regions cuneate; cardinal margin
nearly straight, and about half as long as the valves, gradually
rounding below to the basal extremity. Beaks small, slightly
oblique, and not projecting beyond the cardinal margin. Angle
of the anterior and posterior margin about 50°. Surface smooth,
or with very obscure traces of lines of growth. Length of a
medium size specimen *- ](i inch; greatest width of the valve 7/ie
inch, convexity of valve about % inch.

Position and locality: Oolitic beds of the St. Louis group,
Monroe county. 111.

Collector, A. H. Worthen.

No. 2522 of the Illinois State Museum.

128 PALEONTOLOGY OF ILLINOIS.

GENUS NUCULA, Lamarck.
NUCULA ILLINOIENSIS. Worthen.

PL XIX, Figs. 4-4a.

Xui'iilti Hlinoiensis, Worthen, March, 1884. Bulletin No. 2, of the Illinois State Museum
of Nalural History, page 15.

Shell small, transversely ovate, depressed convex, the greatest
convexity about the middle of the valves ; slightly excavated in
front of the beaks ; anterior end regularly rounded to the ventral
margin, dorsal outline declining moderately from the beaks to
the posterior extremity ; ventral margin slightly curved ; beaks
depressed and situated about one-third the distance from the
anterior to the posterior extremity.

Length 6/1(5 inch; height 4/ie inch. Surface nearly smooth, but
in some of the specimens, faint lines of growth may be seen with
a good lens around the borders of the shell.

Position and locality : Oolitic bed of the St. Louis limestone,
Monroe county, 111.

Collector, A. H. Worthen.

No. 2519 of the Illinois State Museum.

GENUS AVICULOPINNA, Meek.
AVICULOPINNA ILLINOIENSIS. Worthen.

PL XX, Figs. 5-5a.

Aviculopinna iUinoiensis, Worthen. March, 1884. Bulletin No. 2, of the Illinois State
Museum of Natural History, page 13.

Shell rather larger than the typical species, valves moderately
and about equally convex, cardinal and ventral margins curved,
and converging gradually from the base to the apex. Surface
ornamented with numerous thread-like lines or lamellae that
curve gracefully round to the dorsal margin, and are separated
liy rather broad spaces on the dorsal portion of the valve. The
apex is broken away so that its form cannot be determined.

Length 19/10 indies; greatest width % inch; greatest thickness
% inch. This species differs from the A. americana, in the cur-
vature of its margins and the greater convexity of the valves.

INVERTEBRATES. 129

Position and locality: Coal Measures, Peoria county, 111.

Collector, Mr. Gifford.

No. 2529 of the Illinois State Museum.

GENUS SANGUINOLITES, McCoy.

SANGUINOLITES ? MULTISTKIATUS. Worthen.

PL XIX, Fig. 2.

Sanguinolites? multistriatus, Worthen, March, 1884. Bulletin No. 2, of the Illinois State
Museum of Natural History, page 14.

The specimen from which the following- description is drawn,
is a cast from the shaly sandstone of the Keokuk group, and
may be characterized as follows :

Shell below the medium size, oblong, valves moderately convex;
beaks depressed, and situated about one-third the entire length
of the shell behind the anterior extremity.

Dorsal line straight, basal border slightly rounded, extremities
obtusely pointed and apparently gaping, surface marked by
numerous fine concentric striae that are most conspicuous on the
posterior portion of the valves. The specimen is somewhat dis-
torted by pressure, so that its exact proportions cannot be de-
termined.

Length 1 inch; height % inch.

Position and locality- Keokuk shales near Crawfordsville, In-
diana.

Collector, Frank H. Bradley.

No. 2528 of the Illinois State Museum.

SANGUIXOLITES? BURLINGTOXEXSIS. Worthen.

PI. XX, Figs. 8-Sa.

Sangninolites? burling tonens is, Worthen, March, 1884. Bulletin No. 2 of the Illinois State
Museum of Natural History, page 14.

Shell of medium size, longitudinally elongate-ovate, more than
twice as long as high, moderately and evenly convex anteriorly,
and regularly depressed towards the posterior extremity. Car-
dinal margin slightly depressed in the middle and elevated
behind, giving a greater breadth to the posterior than the
anterior region.

-16

130 PALAEONTOLOGY OF ILLINOIS.

Beaks not prominent, and situated close to the anterior ex-
tremity. The specimen is a cast, and shows no surface mark-
ings.

Length !7/ie inches; greatest height ri/i6 inch.

Position and locality: Burlington limestone, Calhoun county,
Illinois.

Collector, A. H. Worthen.

No. 2541 of the Illinois State Museum.

SANGUINOLITES RANDOLPHENSIS. Worthen.

PL XX, Figs. l-la.
Cypricardia? randolphensis, Worthen, 1883, Geol. Surv. of Illinois, Vol. VII, page 326.

Shell oblong, height from beak to the ventral margin about
equal to half the length, valves moderately convex on the an-
terior portion of the shell, and depressed towards the posterior
extremity, where the valves were apparently closely joined.
Beaks rather large, depressed, and incurved beyond the dorsal
margin, and situated about two-fifths the distance from the an-
terior to the posterior extremities. A broad and slightly flat-
tened depression appears on some of the specimens, extending
from the beak to the ventral margin of the shell.

Dorsal margin nearly straight, ventral margin parallel with
the dorsal for about two-thirds of its length, curving abruptly
upward on the anterior and more gently on the posterior ex-
tremity. Lunule ovate; surface markings unknown.

Length of an average size specimen 2% inches; height 1%
inches; thickness 15/16 inch.

All the specimens obtained are casts in limestone.

Position and locality. Chester limestone, upper bed at Chester,
Illinois.

Collector, A. H. Worthen.

No. 2491 of the Illinois State Museum.

INVERTEBRATES. 131

GENUS SOLENOMYA. Lamarck.
SOLENOMYA VARSOViENSis. Worthen.

PL XIX, Fig. 8.

Solenomya Varsoriensis, Worthen, March, 1884. Bulletin No. 2 of the Illinois State
Museum of Natural History, page 12.

Shell rather large, elongate-oval or sub-elliptical in outline,
moderatety convex, and apparently closed at the extremities.
The greatest convexity of the valves is in the umbonal region,
and thence obliquely to the ventral margin, and, in front of
this elevated region, a slight depression may be seen which ex-
tends nearty to the anterior extremity. Beaks depressed and
recurved towards the posterior margin, and located a little less
than one-third the entire length of the valve behind the an-
terior extremity.

Dorsal and ventral margins nearly straight and sub-parallel,
anterior extremity rather narrow, and the posterior broadly
rounded.

Surface of the cast marked by a few obscure wrinkles near
the umbo, and lines of growth towards the ventral margin.

Length about 3 inches; height from the beak to the ventral
margin 1% inches; convexity of the valves about 7/1Q inch.

Position and locality; Keokuk limestone, Warsaw, Illinois.

Collector, A. H. Worthen.

No. 2539 of the Illinois State Museum.

SOLENOMYA MONROENSIS. Worthen.

PI. XVIII, Fig. 5-5a.

Solenomya Monroensis, Worthen, March, 1884. Bulletin No. 2 of the Illinois State
Museum of Natural History, page 13.

Shell below the medium size, oblong, the length being a little
more than twice the height from the beak to the ventral mar-
gin; valves moderately convex, the greatest convexity being
obliquely along the umbonal slopes from the beaks to the ven-
tral margin; cardinal margin straight and about three-fifths
the entire length of the valve; basal margin slightly sinuous,
from a shallow depression that extends obliquely from the beaks

132 PALEONTOLOGY OF ILLINOIS.

to the opposite margins, extremities rounded ; beaks depressed,
oblique, and located about one-sixth the entire length of the
valves behind the anterior extremity.

Surface smooth or showing only a few obscure lines of growth.

Length of the largest specimen obtained 13/ieinch; height
from beak to base 6/16 inch.

Position and locality : Obtained from the oolitic beds of the
St. Louis limestone 011 Fountain Creek, Monroe county, 111.

Collector, A. H. Worthen.

No. 2515 of the Illinois State Museum.

SOLENOMYA? iGWENSis. Worthen.

PL XIX, Fig. 5-5a.

Solenomya? lowensis, Worthen, March, 1884. Bulletin No. 2 of the Illinois State
Museum of Natural History, page 13.

Shell small, narrow, oblong, valves apparently closed at each
extremity.

Dorsal and ventral margins nearly parallel, beaks depressed
and situated close to the anterior extremity. Surface markings
unknown.

Length of the largest specimen 7/io inch; height \ inch;
thickness % inch. This little shell is only known from a few
casts obtained from the shaly layers of the St. Louis limestone
near Pella, Iowa, where it was associated with Allorisma, marion-
ensis, RhynchoneUa ottumwa, Spiriier littoni and Zaphrentis sp?

Collector, A. H. Worthen.

No. 2517 of the Illinois State Museum.

GENUS ALLORISMA, King.
ALLORISMA ILLINOIENSIS. Worthen.

PL XVin, Pig. l-la.

Allorisma illinoiensis, Worthen, March, 1884. Bulletin No. 2 of the Illinois State Mus-
eum of Natural History, page 11.

Shell large, elongate-ovate, length a little more than twice the
height; valves moderately convex, extremities broadly rounded;
dorsal margin straight and nearly parallel with the base; an-
terior extremity short and rather more narrowly rounded than
the posterior, and descending obliquely from the beaks. Beaks

INVERTEBRATES. 133

compressed, extending beyond the cardinal border, and located
about one-fourth the entire length of the shell behind the an-
terior extremity. Surface of the cast ornamented with rather
strong parallel lines of growth.

Length 39/16 inches; height from the beak to the basal mar-
gin 1% inches: convexity of the valves about T/i6 inch.

This species resemblns .1. subcuneata in size and form, but
larks the concentric undulations of that species.

Position and locality: Keokuk limestone, Warsaw, 111.

Collector, A. H. Wort hen.

Xo. 2540 of the Illinois State Museum.

ALLOT? SMA ELOXUATA. Wort-hen.

PI. XIX, Fig. 10.

Allorisma elongata, Worthen. March, 1884. Bulletin No. 2 of the Illinois State Museum
of Natural History, page 12.

Shell large, very elongate, dorsal and ventral margins nearly
straight and parallel: length three times as great as the height;
greatest convexity in the umbonal region: cuneate and perhaps
a little gaping behind, with a rather narrowly rounded outline.
Beaks recurved, approximate, and located near the anterior ex-
tremity. Anterior margin evenly rounded. The surface of the
cast shows numerous concentric undulations that are much
smaller and more numerous than in .4. subcuneata. its nearest
representative form.

Length 315/16 inches: height 15/16 inches; breadth near the
umbo 1% inches.

Position and locality: Keokuk limestone, Warsaw, 111.

Collector. A. H. Worthen.

Xo. 254:2 of the Illinois State Museum.

134 PALEONTOLOGY OF ILLINOIS.

PTEROPODA.

GENUS CONULARIA. Miller.
CONULARIA CHESTER KXKIS. Worthen.

PL XI, Fig. <M»a.
Conularia chesterensis Worthen, 1883. Geol. Surv. of Illinois, Vol. VII, page 325.

Shell attaining a medium size, long and rather slender, grad-
ually tapering, nearly equally four-sided, the four angles being
distinctly and rather deeply furrowed, while a slight furrow
marks the median line on each side. The sides are crossed by
numerous raised costae, which arch slightly forward from the
angles to the median line, making an angle with that line of
about 14°. These costae do not cross the angular furrows, but
are alternately arranged so that those on one side terminate
at the intervening space between those on the opposite side.

These spaces are about twice as wide as the costae, and are
widest at the median line.

The aperture is not well preserved in any of our specimens,
but the shell was evidently notched at the angles, and was pro-
bably contracted at ttie aperture.

Length of a rather large individual, 5 inches; breadth between
the angles near the aperture, 1 inch; number of costae in the
space of an inch near the aperture, 20: near the apex, 30.

Position and locality: Chester limestone, Chester, Illinois.

Collector A. H. Worthen.

No. 2489 of the Illinois State Museum.

ENVERTEBRATES. 135

GASTEROPODA.

GEMS PLEUROTOMARIA, Defrance.
PLEUROTOMARIA ILLI.NOIKNSIS. Wort-hen.

PL XXIII, Figs. 6-6a-6b.

Plenrotomaria illinoifnsis, Worthen, March. 1884. Bulletin No. 2, of the Illinois State
Museum of Natural History, p. 4.

Shell disroiclal. s]>ire but slightly elevated; outer angle of the

volution sharp, volutions about five, aperture ovate.

Suture line marked by a row of small nodes, of which about ten

may be counted on the last volution. A revolving slightly im-

•<1 baud may be seen with a good lens above the outer

angle of the last volution, which probably joins the sinus in the

lip: umbilicus shallow.

This shell is most nearly related to the flat variety of P.

sphferulatci, described by Prof. Cox, under the name of P. de-

pirssn. but differs from that in its more flattened volutions,

the impressed band on the lower volution, and its smaller and

< onspicuous nodes.

Breadth of an average size specimen 9/16 inch; height 3/16
inch.

Position and locality: From a black limestone over one of
the lower coal seams in Mercer county. 111.

Collector, A. H. Wort hen.

No. 2530 of the Illinois State Museum.

PLEUROTOMARIA GIFFORDI. Worthen.

PL XXIH, Figs. 8-«a.

<nria giffordi, Worthen. March, 1884. Bulletin No. 2, of the Illinois State
Museum of Natural History, page 5.

Shell small, conical, volutions about seven, spire sharply ele-
vated, the last volution forming less than half the entire length,

136 PALAEONTOLOGY OF ILLINOIS.

and ornamented below the spiral band with nine or ten revolving
lines, that decrease in number on the succeeding volutions.

Spiral band concave and located a little above the middle of
the lower volution, and defined by two strong revolving lines,
the upper one of which is the strongest. There are also two or
three revolving lines within the spiral band, and three or four
on the upper angle of the volution, the last one of which is
much stronger than the others.

Length 6/i6 inch, diameter of the outer volution about 4/ie
inch; spiral angle about 43°.

This shell is nearly related to P. subconstricta,, Meek and Wor-
then, described and figured in Vol. II of these reports, page 351,
PI. 28, fig. 6, but differs from that in its surface ornamentation,
and especially in its spiral angle.

Position and locality: Coal Measures, Peoria county, 111.

Collector, Mr. Gifford.

No. 2535 of the Illinois State Museum.

PLEUROTOMARIA MONTEZUMA. Worthen.

PI. XXIV, Fig. 2.
Pleurotomaria montezumn, Worthen, 1883. Geol. Surv. of Illinois, Vol. VII, page 324.

This fine shell is only known from an imperfect cast of the
last volution.

Shell attaining a large size, broadly conical in outline ; whorls
three or more, diminishing rapidly in size towrards the apex.
Last whorl obliquely flattened, showing a lateral surface about
two inches in breadth. This is traversed by about eight rather
strong revolving striae, separated by shallow depressions that
are about % of an inch wide near the aperture. The under side
of this volution was also traversed by revolving striae about
half as widely separated as those on the side of the volution,
but their number cannot be accurately determined from the im-
perfect state of preservation of the only individual yet obtained.
A raised line around the inner side of the volution, indicates the
presence of a rather wide and deep umbilicus.

Greatest diameter of the last volution, 4% inches; height of
the volution 1% inches.

INVERTEBRATES. 137

Position and locality : Burlington limestone, Montezuma, Pike
county, Illinois.
Collector. A. H. Worthen.
No. 2487 of the Illinois State Museum.

PLEUROTOMARIA ADAMSI. Worthen.

PL XXm, Figs. 5-5a.

Pleurotomaria adamsi, Worthen. March, 1884. Bulletin No. 2, of the Illinois State
Museum of Natural History, page 5.

Shell small, trochiform, conical; length a little more than the
diameter of the lower volution. Volutions about six, the last
one flat and smooth below the spiral band, umbilical region
concave: spiral band prominent, deeply groved, and occupying
the angle on the periphery of the lower volution, becoming
shallower and less prominent on those above. The elevations
defining the upper and lower margins of the spiral band are
marked by one or two revolving lines visible with an ordinary
glass, which continue on the succeeding volutions where the
spiral band becomes obsolete.

Length 516 inch ; diameter of the last volution 4/16 inch; spiral
angle about 60°.

Named in honor of Mr. W. H. Adams of Peoria county, from
whom some of the specimens were obtained.

Position and locality: Coal Measures, Peoria county, 111.

Collector. W. H. Adams.

No. 2536 of the Illinois State Museum.

PLEUROTOMARIA NAVVOOENSIS. Worthen.

PL XXV, Fig. 3.

Pleurotomaria nauoooensis, Worthen, March, 1884. Bulletin No. 2, of the Illinois State
Museum of Natural History, page 5.

This form is represented in the State collection by a single
cast in limestone from the upper part of the Keokuk limestone
at Navoo.

Shell above the medium size, consisting of about four obliquely
flattened volutions, the lower one forming about half the entire
length. The periphery of the lower volution shows a flattened
space about a quarter of an inch in width that was probably
occupied by a spiral band. Form of aperture and surface mark-
ings unknown.
—17

138 PALAEONTOLOGY OF ILLINOIS.

Length of the three lower volutions 1% inches ; greatest breadth
1% inches.

Collector, A. H. Worthen.
No. 2493 of the Illinois State Museum.

PEUROTOMARIA IOWENSIS. (sp. nov.)

PL XXIV. Fig. 2.

Pleurotomaria Coxana, Worthen, March, 1884. Bulletin No. 2 of the Illinois State
Museum of Natural History, page 6.

When this species was described in 1884, the fact that the
specific name coxana, was already occupied for a Coal Measure
form was overlooked, and therefore the name iowensis is
now substituted for the one originally proposed.

Shell large, broadly umbilicated, spire moderately extended,
its length being equal to about one-third the full length of the
shell; volutions about four, strongly and evenly convex above,
and increasing gradually in size, the last one abruptly rounded
below into the umbilicus; aperture apparently subovate. The
specimen is a cast in limestone, and the surface was probably
nearly smooth, as the fragments of the adhering test show no
external markings.

Length 2% inches; breadth 1% inches; diameter of the last
volution 16/1(J inches.

Position and locality: Keokuk limestone, Keokuk, Iowa.

Collector, Mr. L. A. Cox.

No. 2547 of the Illinois State Museum.

GENUS PORCELLIA, Leveille.
POECELLIA PEORIENSIS. Worthen.

PL XXIII, Fig. 4-4a, 4b.

Porcellia Peoriensis, Worthen, March, 1884. Bulletin No. 2 of the Illinois State Museum

of Natural History, page 6.

Shell small, volutions about five, closely embracing and very
gradually enlarging, the last one marked by a narrow dorsal
band, defined by a sharp elevated ridge on either side. Outer
volution ornamented also with a row of about nine small nodes

INVERTEBRATES. 139

on either side, which are situated about one-third the distance
from the inner margin to the dorsal band. Umbilical depres-
sion broad and shallow.

The surface of the shell in some of our specimens is thickly
pitted with small rounded depressions that are plainly visible
under a good lens, but they may, however, be due to some
secondary cause.

Greatest diameter of the shell % inch; transverse diameter of
the outer volution % inch.

Position and locality : This rare and beautiful little shell was
found in the lower Coal Measures of Peoria county, 111.

Collector, Mr. Gifford.

No. 2531 of the Illinois State Museum.

GENUS LOXOXEMA, Phillips.
LOXONEMA PEORIENSE. Worthen.

PI. XXin, Fig. lo-lOa. lOb.

Loionema Peoriensis. Worthen. March, 18S4. Bulletin No. 2 of the Illinois State Museum

of Natural History, page 7.

Shell below the medium size, elongate conical, spire very grad-
ually tapering to a minute point. Volutions about sixteen, con-
vex, increasing very gradually in size; the lower ones a little
flattened above the middle. Suture moderately deep, surface
smooth. Aperture nearly round.

Length % inch; diameter of the lower volution 3/16 inch.
Spiral angle 16°.

This species is nearly related to L. cerithifonnis of Meek and
Worthen. described and figured in Vol. II of these reports, page
379, PI. 31, fig. 13, a, b, c, but may be readily distinguished
from that, by its more slender form and more numerous volu-
tions.

Position and locality: Coal Measures, Peoria county, 111.

Collector, Mr. Gifford.

No. 2532 of the Illinois State Museum.

140 PALEONTOLOGY OF ILLINOIS.

LOXONEMA QUADRI-CARINATUM. Worthen.
PL XXIH, Fig. 9-9a.

Loxonema quadri-carinatus, Worthen, March, 1884. Bulletin No. 2 of the Illinois State
Museum of Natural History, page 7.

Shell long, cylindrical, gradually tapering; volutions eight or
more, convex, the last one sloping abruptly to the umbilical
region below, and more gradually to the suture above. Volu-
tions ornamented with three strong revolving carinse on the
lower portion of the volutions, and a less defined one on the
upper sloping side below the suture. Transverse lines of growth
are visible under a lens on the abruptly sloping under side of
the last volution. Aperture ovate.

Length of a specimen preserving six volutions 13/io inch;
diameter of the lower volution 6/1(5 inch. Spiral angle 25.°

Position and locality: Coal Measures, Peoria county, 111.

Collector, Mr. Gifford.

No. 2534 of the Illinois State Museum.

GENUS LEPETOPSIS, Whitfield.
LEPETOPSIS CHESTEBENSIS. Worthen.

PL XXV, Pigs. 1-la,

Lepetopsis chesterensis, Worthen, March, 1884. Bulletin No. 2, of the Illinois State
Museum of Natural History, page 25.

Shell of medium size, longitudinally ovate, anterior and pos-
terior portions regularly rounded and about equal in length, a
little broader behind than in front, apex pointed, and directed
slightly backward, height equal to about one-third the greatest
length; A shallow depression or sinus commences immediately
behind the apex and increases rapidly in width the posterior
margin. Surface ornamented with numerous somewhat irregular
sized concentric lines that arch upward in crossing the sinus-like
depression behind the apex.

Length 9/10 of an inch; greatest breadth 7/w inch; height
about 3/10 inch.

This species is related to L. levetti, of the Warsaw beds, but
may be distinguished by its more elongate form, and the sinus-
like depression behind the apex.

INVERTEBRATES. 141

Position and locality: Lower division of the Chester lime-
stone, Chester, 111.
Collector. Mrs. J. C. Salter.
No. 2514 of the Illinois State Museum.

GENUS MURCHISOXIA, D'Arch. and Vern.

MURCHISOMA KEOKUK. (sp. nOV.)
PL XXTTT. Fies. 2-2a.

Several casts of a long spiral shell have been found in the
Keokuk limestone, which seem to belong to the genus Murcbi-
sonia, but none of them retain any portion of the test, and
consequently nothing is known of their external characters.

These casts all have an elongated form that tapers very grad-
ually to the apex. Volutions about six, the upper ones rather
more regularly rounded than the last: suture wide and deep.
Aperture apparently ovate.

Length of a cast with five volutions, nearly 4 inches; great-
est breadth of the last volution 1% inches: transverse diameter
of the same % inch.

Position and locality: Keokuk limestone. Keokuk. Iowa.

The specimens figured were kindly loaned by Mr. L. A. Cox,
of Keokuk.

MURCHISOMA LASALLEXSIS. (sp. nov.)

PL XXV, Figs. 7-7a.

Shell turriculate, slender, spire pointed at the summit, com-
posed of eleven or more volutions, which are elevated in the
middle into a prominent carina, and separated by a profound
suture.

On the last volution there is a flattened band below the ca-
rina. which is bounded below by a slight elevation. Neither the
flattened band nor the elevation below extend to the other vo-
lutions.

Length of the shell *4 inch: breadth of the last volution •'' 16
inch; spiral angle about 22°.

This little shell is closely related to M. sub-angulata, of Ver-
neuil and Keyserling*, but differs in the greater number of its

* Geology of Russia and the Ural Mountains, VoL II, page S40, PL XXII, Fig. 6.

142 PALEONTOLOGY OF ILLINOIS.

volutions, more strongly prominent carina, and in the flattened
band on the lower volution.

Locality and position: Upper Coal Measures, LaSalle, Illinois.

Collector, A. H. Worthen.

No. 2603 of the Illinois State Museum.

GENUS STRAPAKOLLUS. Montfort.
STRAPAROLLUS SUB-UMBILICATUS. (sp. nov.)

PL XXIV, Figs. 3-3a-3b.

Shell small, conical, whorls five, flattened above, rounded on
the periphery and sharply rounded below into the umbilicus.

Umbilicus deep and rather wider than the diameter of the
outer volution near the aperture. Surface without ornamenta-
tion, except some faint lines of growth.

Diameter of a medium size specimen 6/16 inch; height of the
same 5/16 inch.

This little shell is closely related to the £ umbilicatus, Meek
and Worthen, of the Coal Measures, but differs from that spe-
cies in its comparatively narrow umbilicus, and much smaller
size. Of more than twenty specimens obtained, none attain a
diameter of more than half an inch.

Position and locality: Calcareous shales of the Chester group,
near Evansville, Randolph county, 111.

Collector, A. H. Worthen.

No. 2602 of the Illinois State Museum.

STRAPAROLLUS VARSOVIENSIS. (sp. nov.)

PL XXV, Figs. 2-2a.

Shell lenticular, whorls about four, gradually increasing in
size; spire moderately elevated above the body whorl. Volu-
tions somewhat flattened above, and regularly rounded on the
periphery, and more gently below into the umbilicus.

The umbilicus is filled with the stony matrix, but is appar-
ently somewhat less in width than the diameter of the outer
whorl.

The specimen is a cast in limestone, and no external mark-
ings are apparent.

INVERTEBRATES. 143

Height 7 1H inch; greatest breadth 13/16 inch; breadth of the
aperture 6/16 inch.

Position and locality: Upper beds of the Keokuk limestone,
Warsaw. 111.

Collector, A. H. Worthen.

No. 2599 of the Illinois State Museum.

GENUS MACROCHEILUS. Phillips.
MACROCHEILUS ALTONENSIS. (sp. nov.)

PL XXIV. Figs. l-'a.

Shell of medium size, subfusiform, symmetrically conical
above the last volution.

Volutions about six. moderately ventricose. the last one about
equal to the length of the spire above. Suture well denned.
Aperture elongate ovate; surface markings unkown.

The specimen is a cast in limestone, but clearly shows the
characteristics of the genus.

Length 1% inches; length of the last volution 1 inch; breadth
of the same % inch ; length of aperture % inch ; greatest breadth
of the same % inch.

Position and locality : St. Louis limestone, Alton. Illinois.

Collector. A. H. Worthen.

No. 2598 of the Illinois State Museum.

GENUS BELLEROPHON, Montfort.
BELLEROPHON GIGANTEUS. Worthen.

PI. XXV, Figs. 5-oa.

Bellerophon giganteus Worthen, March, 1884. Bulletin No. 2 of the Illinois State
Museum of Natural History, page 8.

Shell very large, sub-globose: volutions expanding rapidly,
rounded over the dorsum and sides ; umbilical region deeply ex-
cavated. Aperture reniform or sublunate, mesial band not
shown on the cast. Fragments of the shell adhering show that
it was comparatively thick.

144 PALAEONTOLOGY OF ILLINOIS.

Greatest breadth of the aperture about 4 inches; height of
the same 2% inches; length from front to back 313/16 inches.

This shell is only known from a cast in limestone, but it may
be readily distinguished by its size and general form from all
known American species.

Position and locality : Lower Coal Measures, Monroe county,
Illinois.

Collector, A. H. Worthen.

No. 2543 of the Illinois State Museum.

GENUS NATICOPSIS. McCoy.
NATICOPSIS MADISONENSIS. Worthen.

PL XXV, Figs. 4,6.

Naticopsis madisonensis, Worthen, March, 1884. Bulletin No. 2 of Ihe Illinois State
Museum of Natural History, page 9.

Shell large, sub-rhomboidal or sub-rectangular in outline ; vol-
utions about three, the last one comprising more than two-
thirds the entire length of the shell, all rounded, and the last
quite gibbous; umbilicus deep, aperture apparently subcircular.
The specimen is a cast in limestone, and shows no external
markings except some faint lines of growth.

Length 21/16 inches; breath of the last volution 15/16 inches.

In form and size this shell approaches most nearly to N.
giganteus of the Coal Measures, but it differs from that in
having one less volution, and it also lacks the flattened depres-
sion on the outer volution which characterizes that species.

Position and locality: St. Louis limestone, Madison county,
Illinois.

Collector, A. H. Worthen.

No. 2546 of the Illinois State Museum.

GENUS POLYPHEMOPSIS. Portlock.
POLYPHEMOPSIS? KEOKUK. Worthen.

PL XXIII, Fig. 3.

Polvphernopsis? Keokuk, Worthen, March, 1884. Bulletin No. 2 of the Illinois State
Museum of Natural History, page 9.

A cast of this shell in limestone from the lower portion of
the Keokuk limestone in the vicinity of Keokuk presents the
following characters :

INVERTEBRATES. 145

Shell about the medium size, consisting of about five moder-
ately convex volutions, the last one constituting more than
one-half the entire length. The volutions taper gradually, and
present no indications of external ornamentation.

Exact form of aperture unknown. Length of the four volu-
tions preserved, 2% inches; length of last volution, 1% inches;
breadth of the same where it seems to be somewhat flattened
by pressure, % inch.

Collector, Mr. L. A. Cox, of Keokuk.
No. 2494 of the Illinois State Museum.

GENUS DENTALIUM. Linnams.
DENTALIUM ILLINOIENSE. Worthen.

PL XXIII, Fig. 1.
Dentallum illinoiense, Worthen, 1883. GeoL Surv. of Illinois. VoL VII, page 325.

Shell above a medium size, long, straight, cylindrical, slightly
tapering, scarcely inflated at the aperture. Surface apparently
smooth originally, but slightly roughened by weathering in the
specimen under examination.

Length 5% inches; width near the aperture, 7/io inch.
This species differs from D. missouriense of Swallow, in its
larger size, smooth surface and straight form.
Position and locality: Chester limestone, Chester, 111.
Collector, A. H. Worthen.
No. 2488 of the Illinois State Museum.

GENUS ORTHONEMA. Meek and Worthen.

ORTHONEMA CARBONARIUM. Worthen.
PL XXIV, Figs. 4-4a.

Orthonema carbonaria, Worthen, March, 1884. Bulletin No. 2, of the Illinois State
Museum of Natural History, page 7.

Shell very elongate, gradually tapering from the base to the
apex, with nine or more flattened volutions that are defined
—18

146 PALAEONTOLOGY OF ILLINOIS.

above and below by a narrow suture, and a strong revolving
carina. Under side of the last volution obliquely flattened; um-
bilicus closed. Form of aperture not clearly defined, but appar-
ently subovate. Lines of growth are clearly visible on the flat
portions of the volutions. Length of a specimen showing seven
volutions, 10/16 inch; diameter of lower volution % inch. Spiral
angle about 20°.

This shell is known only from an imperfect example, and is
nearly related to O. salteri, of Meek and Worthen, Vol. II, of
these reports, page 381, PI. 31, fig. 14, a, b, c, but differs from
that, in its surface ornamentation and its spiral angle.

Position and locality: Coal Measures, Peoria county, 111.

Collector, Mr. Gifford.

No. 2533 of the Illinois State Museum.

GENUS TRACHYDOMIA. Meek and Worthen.

TRACHYDOMIA NODULOSA. Worthen.
PL XXIII, Figs. 11-lla.

Trachydomia nodulosa. Worthen, March' 1884. Bulletin No. 2, of the Illinois State
Museum of Natural History, page 8.

Shell of medium size, obliquely ovate or sub-rhomboidal in
outline, volutions four, the last one comparatively large and
comprising more than two-thirds the entire length, rounded
below and slightly flattened above to the nearly perpendicular
lower border of the rather deeply impressed suture. Aperture
nearly sub-ovate with a well defined notch at its lower ex-
tremity; lip sharp, columella flattened and smooth; surface
thickly covered with prominent rounded nodes that are largest
on the upper edge of the volution, and increase in number as
they decrease in size towards the umbilical region. The nodes
become obsolete on the lower extremity of the last volution,
leaving a limited space around the lip that is ornamented only
with a few rather coarse h'nes of growth.

Length of an average size specimen 10/16 inch; breadth 7/lQ
inch.

INVERTEBRATES. 147

This shell is about midway in form and size between T.
wbeeleri and T. hollidayi, but differs from both in the form of
its aperture, and from the latter also in its more numerous and
differently formed nodes.

Position and locality: Coal Measures, Peoria county, HI.

Collectors, W. H. Adams and Mr. Gifford.

No. 2538 of the Illinois State Museum.

148 PALEONTOLOGY OF ILLINOIS.

CLASS CEPHALOPODA.

GENUS NAUTILUS. Breynius.
NAUTILUS MONTGOMERYENSIS. Worthen.

PL XXVI, Fig. 2 and XXVII, fig. 1.

Nautilus montg ornery ensis, Worthen, March, 1884. Bulletin No. 2, of the Illinois State
Museum of Natural History, page 4.

Shell of medium size, sub-globose, volutions two or more,
rapidly expanding ; outer septum regularly rounded in front and
on the sides, wider than long, with a wide and deep sinus in
the middle of its dorsal border for the reception of the broad
tongue-like projection of the next septum. The succeeding septa
are much narrower, and more broadly curved on their dorsal
sides, with a long and broad tongue-like projection in the
middle that fills the sinus of the preceding septum. Position of
the siphuncle unknown. The specimen is a cast in clay iron-
stone and shows no surface ornamentation.

Aperture reniform in shape, and 33/34 inches in breadth by
1% inches in height. Length of the shell from front to back 3%
inches.

Position and locality: Upper Coal Measures, Montgomery
county, 111.

Collector unknown.

No. 2544 of the Illinois State Museum.

GENUS OETHOCERAS. Breynius.
ORTHOCERAS ILLINOIENSE. Worthen.

PL XXVI, Figs. l,la, Ib.
Orthoceras illinoiense, Worthen. 1883. Qeol. Surv. of Illinois, Vol. VII, page 323.

Shell of medium size, gradually enlarging from the apex; sec-
tion slightly ovate, siphuncle rather large, and placed near the

INVERTEBRATES. 149

margin of the shell. Septa moderately convex and oblique to
the axis, being arched strongly upward on the siphuncular side,
and equaling in width about one-fifth the shortest dianfeter of
the shell. Surface markings unknown.

Length of the largest specimen seen, about 6 inches; greatest
width at the apex % inch ; diameter of outer chamber 2% inches.

Position and locality: Chester limestone, Chester, 111.

Collector, A. H. Worthen.

No. 2484 of the Illinois State Museum.

ORTHOCERAS OKAWENSE. Worthen.

PL XXVI. Fig. 3.
Orthoceras okawense, Worthen. 1883. Geol. Surv. of Illinois. VoL VII, page 324.

Shell elongate, slender, very gradually tapering to the apex;
septa concave, about four of them in the space of one diameter.
Siphuncle sub-central; surface markings unknown.

This shell has a general resemblance to O. rushense, Mc-
Chesney of the Upper Coal Measures, but differs from it in the
position of the siphuncle, which in our species is decidedly sub-
central.

Position and locality : Chester limestone, near Red Bud, Ran-
dolph county, 111.

Collector, A. H. Worthen.

No. 2485 of the Illinois State Museum.

ORTHOCERAS LASALLENSE. Worthen.

PL XXVL Figs. 4-te.
Orthoceras lasallense, Worthen. 1883. Geol. Survey of Illinois, VoL Vli, page 324.

Shell small, gradually tapering. Surface ornament with trans-
verse ridges or elevations, situated at regular distances from
each other, and with delicate thread-like striae which cover the
transverse ridges as well as the spaces between them.

The ridges and striae will serve to distinguish this species from
any hitherto described from the Coal Measures, its ornamenta-
tion resembling a Silurian form, O. undulatum, of the Niagara
limestone, more closely than any other known American species.
The fragment preserved and figured seems to belong to the non-
septate portion of the shell.

150 PALEONTOLOGY OF ILLINOIS.

Position and locality: Roof of the middle coal seam, LaSalle,
Illinois.

Collector, A. H. Worthen.
No. 2486 of the Illinois State Museum.

GENUS GONIATITES. DeHaan.

GONIATITES MONROENSIS. (sp. nOV.)
PL XXVI. Fig. 5.

Shell of medium size, discoid, compressed, whorls about four,
contiguous, sides slightly rounded, but narrowly rounded on the
dorsum.

Lateral diameter of the whorls, slightly less than the dorso-
ventral at the middle of the last volution ; width of the umbilicus
equal to about once and a half that of the dorso-ventral diame-
ter. The lower margins of the volutions are sharply rounded
into the umbilicus.

Septa composed of two rounded lobes on each side with an
obtusely pointed projection between them. Surface smooth.

Greatest diameter 1% inches; lateral diameter of outer whorl
% inch; dorso-ventral diameter near the aperture 9/16 inch.

Locality and position : This species is represented by a single
specimen only, which was obtained from a thin bed of partly
brecciated limestone that forms the upper part of the St. Louis
limestone near Waterloo, Monroe county, Ills.

Collector, A. H. Worthen.

No. 2589 of the Illinois State Museum.

GENUS SOLENOCHEILUS, Meek and Worthen.

SOLENOCHEILUS INDIANENSE. (sp. nOV).
PI. XXVIII, Figs. 1-la.

Shell moderately large, sub-globose in form; umbilicus deep
and about two-thirds as wide as the dorso-ventral diameter;
test thin and without ornamentation.

Septa comparatively wide, two and a half equaling in width
the dorso-ventral diameter, the outer ones curving gently for-
ward on the dorsal portion of the shell.

INVERTEBRATES. 151

The outer chamber is only partially preserved, but must have
measured from seven to eight inches in width when complete.

Siphuncle small and situated near the dorsum.

We have seen but a single specimen of this fine shell, which
was obtained from the upper beds of the St. Louis limestone at
Greencastle, Indiana, where it was associated with Temnocheilus
coxanum, Solenocheilus collection. Orthoceras, etc.

Collector, A. H. Worthen.

GENUS TEMXOCHEILCS. McCoy.
TEMNOCHEILUS SCOTTENSE. (sp. nov.)

PL XXVH, Figs.3-3a.

Shell of medium size, subdiscoidal, sides of the volutions
broadly rounded, dorsum nearly flat on the chamber of habita-
tion: and depressed convex on the remainder of the outer volu-
tion ; volutions about three and a half ; umbilicus wide and
deep, showing nearly the whole of the second volution; test
thin, and apparently without external ornamentation. The
outer chamber occupies nearly one-half the outer volution.

Septa arching slightly backward on the sides, and separated
on the dorsum, by a space equal to about one-fourth the trans-
verse diameter of the volution.

Greatest diameter of the specimen in hand, 3% inches; trans-
verse diameter of the chamber of habitation, 1% inches; dorso-
ventral diameter of the same !5/i6 inches.

Position and locality: Warsaw beds of the St. Louis lime-
stone, near Winchester, Scott county, Illinois.

No. 2587 of the Illinois State Museum.

GENUS ASCOCERAS. Barrande.

ASTOCERAS SOUTHWELLI. (sp. nOV.)
PI. XXVII, Figs. 2-2a.

This rare species is represented by two imperfect specimens
only, the one figured being the most perfect of the two in hand.
This shows only the chamber of habitation, the form of the
septate portion, and the extremity of the siphuncle.

152 PALAEONTOLOGY OF ILLINOIS.

Shell small, cylindrical at the upper extremity, and slightly
inflated below, giving it when the septate portion is preserved
a slightly ovate outline.

Dorso-ventral diameter a little more than the lateral, and
greatest about midway between the two extremities. Septa
not preserved but apparently about two. Siphuncle proportion-
ately large, septate, and situated close to the dorsal side.

Length of the best preserved specimen, incomplete at the
upper extremity 1%6 inches; breadth of the dorso-central side
about midway of its length 7/16 inch; breadth of opposite side
6/16 inch.

Position and locality: Niagara limestone, Port Byron, 111.

Collector, J. H. Southwell.

No. 2588 of the Illinois State Museum.

INVERTEBRATES. 153

ORDER CRUSTACEA.

GENUS COLPOCARIS. Meek.
COLPOTARIS CHESTERENSIS. Worthen.

PI. XXVIII, Fig. 2.

arii* chesterentis, Worthen, March, 1884. Bulletin No. 2 of the Illinois State
Museum of Natural History, page 3.

Carapace valves, large, elongate, ovate in outline, more than
twice as long as high, the widest portion being about the
middle: broadly and evenly curved from end to end on the
dorsal margin: ventral margin nearly straight for about two-
thirds its length, and then gradually curving upward to the
evenly rounded anterior extremity.

The posterior extremity of our specimen is broken away so
that it.s form cannot be clearly determined.

Length 2\ indies: givatest width. 1 inch.

Position and locality: From the lower division of the Chester
limestone. Chester. Illinois.

Collector. A. H. Worthen.

No. 2496 of the Illinois State Museum,

SOLKXHCAKIS. Meek.

•ENOCABIti >\M TI-I.l Uoviri. Worthen.
PL XXVIII, Fig. 3.

<<. Ludorici. Worthen. March, 1881. Bulletin No. 2 of the Illinois State
Museum of Natural History, page.

Carapace valves narrow and elongated, the length being equal

to about three times the height, probably slightly convex

though flattened on the surface of the limestone: dorsal and

ventral margins nearly straight and parallel: anterior end

—19

154 PALAEONTOLOGY OF ILLINOIS.

curving1 regularly upward to the dorsal margin; posteflfor
terminating in an obtuse point, the ventral margin being more
strongly curved at both extremities than the dorsal. The sur-
face is covered with round pits which are most numerous and
conspicuous near the margins, with traces of delicate longitu-
dinal striae along the center of the valve when viewed under a
good lens.

Length 14/10 inch; height, 4/i« inch.

Position .and locality: St. Louis limestone, South St. Louis,
Mo.

Collector, A. H. Wortheu.

No. 2497 of the Illinois State Museum.

PART II.
PALEONTOLOGY OF ILLINOIS.

SECTION II.

NEW SPECIES OF CRINOIDS AND BLASTOIDS FROM THE KINDER-
HOOK GROUP OF THE LOWER CARBONIFEROUS ROCKS
AT LE GRAND, IOWA.

AND

A NEW GENTS FROM THE NIAGARA GROUP OF
WESTERN TENNESSEE.

BY CHARLES WACHSMFTH AND FRANK SPRINGER.

I'ltlXDiriS AND BLASTOIDK. 157

CRINOIDS AND BLASTOIDS.

Quite a number of Oinoids and Blastoids, witli one or two
exceptions representing new species, have been recently dis-
covered at Le Grand on the Chicago and Northwestern Railroad .
a few miles east of Marshalltown, in Marshall county. Iowa.
The quarries at that locality have been in operation for many
years, yielding- a most excellent limestone, in part oolitic.*

The exposure at Le Grand embraces about fifty feet of verti-
cal thickness. The base of the quarries consists of a fine-grained
blue sandstone, which has been used for curbing. This is suc-
ceeded by about 18 feet of heavy bedded, whitish grey oolitic
limestone, containing many shells and remains of fishes. Above
this is a succession of limestone beds of about 35 feet total
thickness. The lower part is subcrystalline, bedded in layers of
moderate thickness. It is succeeded by a fine-grained, brownish
or buff magnesian limestone, which at first is somewhat irregu-
larly bedded in rather thin strata, but toward the top occurs
in massive layers from 2 to 4 feet thick. Below the heavy beds
there are several thin layers of soft, sandy limestone, and these
contain the remains of Crinoids in remarkably fine preservation,
as the specimens herewith illustrated abundantly show, and
they occur in large quantities.

*The oolitic layers, which are easily cut and polished, have been used ox ensively
for ornamental work and heavy masonry. The stone has proved to be a good building
material, and its dut ability is said to be well established by tests of many years. It has
outlived the prejudice which arose against it when first brought into use, based upon
the tendency of oolite in some other localities to crumble, a fault from which the Le
Grand rock appears to be free.

158 PALEONTOLOGY OF ILLINOIS.

A few Crinoids have been discovered in irregular deposits both
above and below this bed, and they are for the most part of
distinct species.

Next in order are some thin beds of impure limestone, inter-
spersed with bands of chert, and a thin bed of oolite half way
up. They contain fish remains, including some large teeth and
fragments of spines of enormous size, and from this portion of
the quarry we obtained a Crinoid apparently belonging to the
Lower Burlington fauna.

The rocks at Le Grand have long been understood to belong
to the Kinderhook epoch, and among other characteristic fossils
a few Crinoids had been collected; but it was not until re-
cently that the rich crinoidal bed to which we have alluded was
discovered.

Within the last two years fine collections have been made by
Hon. Delos Arnold, Dr. N. S. McBride, Dr. N. B. Waters, of
Marshalltown, and by one of the authors. The quarries are
worked by a company, of which Mr. G. F. Kirby is President,
Mr. H. J. Howe, Secretary and Treasurer, and Mr. Gregg, Super-
intendent. The above named gentlemen have formed a scientific
association, which has exclusive control of the collection and
disposition of the specimens. It is to their courtesy that one
of us is indebted for the opportunity to examine the fossiliferous
deposits in situ, to study the specimens, and to make some
interesting collections for himself. He avails himself of this op-
portunity to tender to Messrs. Arnold, McBride and Waters his
grateful acknowledgments for the invitation to make the excur-
sion with them, to Mr. Kirby for unusual facilities most
generously placed at our disposal, and to all these gentlemen
for their many acts of personal kindness and hospitality.

The geology of this locality has been very clearly described
by Dr. C. A. White, in his Report on the Geology of Iowa, 1870,
Vol. I, pp. 196-7, where he points out the relation between the
rocks in the neighborhood of Le Grand and Indiantown, and
the Kinderhook beds at Burlington. He concludes that the
heavy oolitic bed represents No. 6, and the superincumbent
strata No. 7, of his Burlington section. We see no reason
to differ with the distinguished author in this reference, further

CKINOIPS AND BLASTOIDS. 159

than to observe that the upper part of No. 3 of the Le Grand
and Indiantown section is, in our opinion, very probably the
representative in part of the Lower Burlington limestone.
Dr. White, indeed, notes this resemblance 'in his explanation of
the Indiantown section, on p. 196. In the upper layers we found
a specimen of Actinocrinux prohowidnliH which is one of the
most characteristic species of the Lower Burlington.

By reference to Dr. White's admirable description of the beds
at Burlington, in 'the Boston Journal of Natural History, Vol.
VII, No. II, p. 21"), ft .s-fv/, published in 1860, it will be seen
that his bed No. 7 is divided into three portions, without, how-
eve?-, any definite line of separation. The lower portion is irregu-
lar in character, being partly magnesian limestone, in some
places somewhat silicious, in others tolerably pure limestone.
The middle portion is a rather pure limestone composed to a
great extent of the remains of Crinoids more or less solidly
cemented together. The upper portion consists of impure cherty
limestones and silicious shales. The division between the lower
and middle portions of this bed was taken as an imaginary line
between the true Devonian (as these Kinderhook beds were then
considered,) and the Carboniferous strata, indicating approxi-
mately the limits of the two systems. The middle portion is
what has since been known as the Lower Burlington limestone,
and the upper portion as the beds of passage into the Upper
Burlington. In other words, in practice, all beds below Dr.
White's imaginary line are Kinderhook, and all above it Bur-
lington.

Comparing these features writh what we have observed at Le
Grand, we are inclined to think that the strata from the oolitic
bed up to the top of the brown and buff magnesian limestone,
represent the lower portion of White's No. 7, and that the thin-
bedded cherty limestone above is equivalent to the upper part
of that bed: the middle or crinoidal Lower Burlington being
feebly developed. This, if correct, would make the Le Grand
exposure Kinderhook, as far up as the top of the magnesian
limestone only.

Very few Echinoderms have been found in the Kinderhook
elsewhere. In the paper above referred to, Dr. White gives a

160 PALAEONTOLOGY OF ILLINOIS.

list of the genera discovered at Burlington, in which he notes
."» genera of Oiuoids, and one of Blastoids as occurring in the
lower portion of bed No. 7, and 3 genera in No. 6. Our obser-
vations are to the effect that Kinderhook Crinoids in this
region are extremely rare, and that the authenticity of some of
the few that have been reported from that horizon since the
appearance of Dr. White's paper, is very doubtful.

The Waverly beds in Ohio, which are probably the equivalent
of some member of the western Kinderhook, have yielded a very
interesting crinoidal fauna, to which in general features the Le
Grand crinoids bear a certain resemblance, though no identical
species have been observed. Still closer, however, is the resem-
blance between the Le Grand and Lower Burlington species; but
even among them we have not been able to positively recognize
more than one or two species characteristic of both beds,
besides the specimen from the upper layers to which we have
alluded. However, there are several other species which are
closely allied, and the same genera occur in both beds; but, as
a rule, those from Le Grand indicate in one way or another a
somewhat lower state of development. This is most readily ob-
served among the species of Batocrinus and DorycrimiN, in
which some of the generic characteristics are, as yet, partly
undeveloped, although the tendency toward them is manifested,
ll is also shown in Megistocrinus, of which both Le Grand
species have a subceutral anal opening like the Devonian species
of this genus, instead of a lateral one placed within the brachial
zone, as in the Burlington species.

It appears that the LeGrand Crinoids were deposited in very
quiet waters, and in many cases were imbedded just as they died.
They occur in nests or colonies, and the genera and species are
commingled indiscriminately. It is therefore a curious fact, that
while the specimens of some species are of a pure calcareous com-
position and of a very light color, those of others, under pre-
cisely similar conditions, lying side by side with them, some-
times even with stems and arms intertwined, are harder and of
a very dark, brownish grey color. The contrast between some
of them, indeed, is very marked, and so far as observed, con-

CRINOIDS AND P,LAST< >IDS. 101

stant for the species, so as to be quite a reliable character for
identification. There are of course intermediate shades of color
between the lightest and darkest, but. as a general thing, speci-
mens of the same species have a uniform shade.

The conditions of preservation of the LeGrand Crinoids are
such as to give unusual opportunities for examining the stems.
We found there a number of specimens having the stems intact
almost to the extremities of the roots and cirrhi. The stem in
all of them is short — shorter than has generally been supposed
to be the case among Paheocrinoidea of this period.

In all species >»f the Camerata which have come to our notice,
the lower portion of the stem is provided with small irregular
cirrhi. given off at intervals singly from different sides. In a
species of Graphiocrinns, however, we found the cirrhi thickly
distributed all along the stem from the basals down : and a
similar structure we observed in certain species of Seapbiocrwns
lately found by us in Kentucky. It is also worthy of note that
in all our perfect specimens from LeGrand. as in those from
Burlington and CYawfordsville. the stem tapers to a tine point,
giving off rootlets in all directions, and that there is in no in-
stance any indication of an attachment by the column to a
solid substance. Similar observations have been made by us
upon detached steins ami roots, which at Burlington are found
in countless numbers, but among all the specimens which we
have examined there were only a few — not a half dozen in all —
showing a place of attachment, and in these exceptional c.-i
the stem terminated not in form of a plate, such as we find in
the Pentacrinoid larva of Antedon, but in a mass of flattened
roots. This seems to us of considerable importance as bearing
upon the question whether the Pakeocrinoids generally wen-
attached permanently, or perhaps in their adult state led a
kind of semi-free life, somewhat similar to recent species of
Pentacrinux (Challenger Report on the Stalked Crinoids. pp. 18
and 10. PL 10. Fig. 1.) Taking everything into considera-
tion, it seems to us the numerous small rootlets, spreading in
all directions lead to the conclusion that those Crinoids,
with but few exceptions, either lived upon a soft oozy bottom,

—20

162 PALAEONTOLOGY OF ILLINOIS.

in which they were rooted like plants, or that the rootlets
served as an anchor, by which the animal attached itself to
foreign bodies.

Since the above was written we have discovered in the main
bed at LeGrand another well marked species of Dichocrinus
and a small species of Scaphiocrinua, both new, which remain
undescribed.

CHIXOTDS AND BLASTOIDS. 163

CLASS PELMATOZOA.
ORDER CR1XOIDEA.

SUBORDER CAMERATA.

FAMILY ACTINOCRINID.E.

GENUS ACTINOCRINUS.

AtTIXOCRIXUS ORXATISSIMUS (llOY. Sp.) W. & Sp.

PI. XVI, Fig. 9. A specimen with arms, showing the posterior side.
PI. XVII. Fig. 3. A specimen without arms; anterior view.

This beautiful species has close affinities with Actinocrinus
tenuisculptus McChesney. from the Lower Burlington limestone,
which Hall redescribed in 1860, under the name of A. chloris. It
has a similar style of ornamentation, and the same number of
arms.

In A. temrisculptus, however, the arms are arranged in clus-
ters, the interradial spares are wide and deeply depressed, and
this depression, which extends ventrally to the proximal plates,
gives to the calyx a decidedly lobed appearance not observable
in our species, neither dorsally nor ventrally. It also resembles
Actinocrinus ihiphne from the Waverly group of Ohio; but A.
ornutissimus has tooth-like processes on the back of the arms,
which are wanting both in the Burlington and Waverly species.
The specimens are always light colored.

Dorsal side of the calyx somewhat depressed, sides convex as
far as the top of the secondary radials. whence they spread
more rapidly to the arm bases. Basals short; scarcely notched
along the sutures, extending outward and forming a rim.

164 I'AL.KONTOLOGY OP ILLINOIS.

Primary radials decreasing in size in ascending order, all
three wider than high. First radials hexagonal and heptagonal;
the second quadrangular with convex sides; the third axillary.
Secondary radials 1x10; axillary; supporting the two main
divisions of the ray. Each of these plates is succeeded by two
pieces, of which only the inner one of each ray bifurcates again,
giving off two simple arms; while the outer ones, which are
truncate above, support a row of fixed cuneiform brachials.
The latter are alternately arranged, and interlock on becoming
free. There are six arms to the ray, or thirty in all. Excep-
tions to this rule are not unfrequent, some of the rays having
occasionally five, others seven arms.

Arms long; moderately stout, rounded along the back; their
tips curved and folded inwards. They are composed of two
series of joints, alternately arranged. About every second to
fourth joint of each series is longer and bears a conspicuous
tooth-like node, giving two alternating rows of nodes on the
back of each arm. The intervening joints are very short and
connected vertically by waving sutures. Pinnules closely packed
together, contiguous. They are composed of short joints, each
one provided laterally with a short, tooth-like projection.

Interradials variable in size; the first comparatively large;
occupying fully one-half or more of the interradial space in the
dorsal cup, and extending up to the middle of the third radials.
The first supports two very small pieces in the second range,
.succeeded by two still smaller ones, and others which constitute
a part of the ventral covering. The ventral side consists of
small, irregular pieces, interspersed with larger ones which are
tuberculous. The first anal plate is as large as the first radials
or larger, and generally higher. It supports two plates which
are smaller than the first interradial of the four regular sides.
The next row consists of three much smaller pieces, two of
them interradials, which enclose a second anal plate, with two
small plates above. All succeeding pieces are ventral in position
and form part of the anal tube. The regions above the arm-
has* 's arc hemispherical, not turbinate as in the allied Burling-
ton species, and the anal tube, at its base, is comparatively

CRIXOIDS AND BLASTOIDS. 105

small, and apparently short. There are generally also two or
three interaxillaries. and frequently a small interbrachial between
the arm ba-

Summit plates larger than their surrounding pieces and nodose,
but smaller than in allied forms. The central plate and proxi-
mals, although distributed with the usual regularity, are com-
paratively small.

The ornamentation gives to this species a beauty which is
not surpassed by any other Actinocrinus. The plates of the
calyx are comparatively thin, and the suture lines difficult to
distinguish : they are not convex, but their surface is marked
by a system of sharply elevated, very prominent ridges, pass-
ing from plate to plate, meeting in large stellate clusters on
the interradial spaces. The ridges follow the middle of the radial
series, they are very conspicuous, and pass without interruption,
from the basi-radial suture into the arms, increasing a little in
width toward the arm bases. There are also bead-like elevations,
definitely arranged over the plates, and sometimes surmounting
the ridges. The sculpturing formed by this combination of
ridges and beads is very remarkable and constitutes a most
interesting feature of the species.

Column round, composed of joints alternating in size; edges
of the internodal joints sharp, the intermediate ones rounded
and crenulated. A similar crenulate structure is found around
the projecting rim of the basals, giving it a resemblance to a
stem joint.

Geological position, etc.: Kinderhook beds of the Lower Car-
boniferous, LeGrand, Marshall County, Iowa.

Our own collection.

Af.TINOORIXrS XODOBRACHIATUS (nOV. Sp.) W. & Sp.

PI. XV, Fig. 5. Specimen with arms, from the anterior side.

PL XVI, Fig. 10. Specimen without arms, from the posterior side.

Of the type of Actinocrinus proboscidalis Hall, but with a
larger number of arms, which are less robust, and ornamented
on the back with conspicuous nodes, of which no trace is found
in the Burlington species. It also resembles our A. ornatisxi-
mus. especially in the arm structure, but the nodes are dis-

!(>(> PALAEONTOLOGY OF ILLINOIS.

tributed at greater intervals and are longer. The two species
also differ in their style of ornamentation. The calyx plates of
A. nodobraclriatus, are strongly convex, the suture lines deeply
excavated, and the radiating ridges which cover the plates are
not continuous. The ridges, though generally well defined along
the edges of the plates, either disappear entirely in the central
portion, or become indistinct even in the best specimens, and
appear as if they had been worn off by attrition. The specimens
are light colored with a slight brownish tint.

Dorsal side of the calyx bell-shaped, sides moderately convex,
spreading on approaching the arm bases. Basals short, ex-
panding into a conspicuous rim with a sharp edge, which pro-
jects beyond the limits of the column. Interbasal sutures
deeply notched, making the basal disk distinctly tripartite.

Primary radials decreasing in size upward; the first plate as
high or higher than wide; the second wider than high, hexangu-
lar, exceptionally pentangular, or even quadrangular when not
in contact with the interradials of the second range; the third
twice as high as wide. Secondary radials 1X2X5, almost as
large as the preceding axillaries. There are 1X2X10 tertiary
radials; the inner ones axillary, giving off t\vo arms, one from
each side; the outer ones truncate; supporting a single arm;
thus giving six arms to every ray or thirty to the species, with oc-
casional exceptions. The higher radials retain the embryonic
character of arm plates; they are cuneiform, and immediately
on becoming free change into two series of transverse pit M-OS.

Arms equidistant, crowded at their bases, and taking an out-
ward direction ; they are very long, rounded on the back, taper-
ing upward, the tips deeply infolded, sometimes reaching down
to the calyx. They are biserial, the places of each series united
longitudinally by straight sutures. Upon the back of the arms
there is a series of large tooth-like nodes, whose sharp points
are directed upwards. They are larger, but not so regularly
arranged as those of the preceding species, and are farther
apart, occurring usually either on the sixth, eighth or tenth
joint. These nodes are not confined to one plate only, but
generally extend over two or more, sometimes covering even a

CRINOIDS AND BLASTOIDS. 167

portion of the vertical suture which unites the two series of the
arm. Pinnules long, constructed and arranged as in A. orna-

tisshuus.

Interradials five to seven up to the arm bases. The first is
hexagonal, in size equal to the second radials. The second and
third ranges consist of two pieces, which are comparatively
large. First anal plate about the size of the first radials, but
angular above instead of truncated. It supports two interra-
dials. succeeded by ranges respectively of three, two and two
plates. There is one interaxillary, but no interbrachial piece.

The ventral side is hemispherical, composed of a large number
of very small, smooth plates, interspersed with prominent
spiniferous ones representing the summit plates. The various
summit plates are separated from one another by the smaller
pieces, as in Mcgixtocrinus. and so are also the different orders
of radials. which are represented likewise by spiniferous plates.
The central plate forms the base of the ventral tube: the latter
is located almost centrally, and does not extend to the tips of
the arms.

The surface of the plates on the dorsal side is marked by
numerous broad, indistinct ridges, passing singly or in pairs
from the middle portions of the plates to adjoining pieces.
Those connecting the radials and ascending to the arm bases,
are not stronger than any of the others, a character by which
this species is readily distinguished from A. ornatissimus.

Column round, moderately strong, and composed of alter-
nately large and small joints, rounded at their edges. In a
specimen in our collection, apparently of full growth, in which the
column is preserved to its termination, it is about fifteen inches
long. The upper half of the stem is stouter than the lower half,
which ultimately terminates in a sharply pointed root. At the
upper end. the nodal joints project largely over the intermediate
ones, which are also shorter, but the latter grow gradually in
length and width, until at the middle of the stem they equal in
size the nodal ones, which appear to be correspondingly somewhat
diminished. This change goes on more rapidly toward the end of
the stem, where the joints lose that convexity which is so marked
in the proximal region, and become uniform. The lower por-
tions of the stem are provided with a few thread-like lateral

168 PALEONTOLOGY OF ILLINOIS.

cirrhi; there are no regular branches such as we find in most
of the Burlington species, and we doubt if this specimen, and
several others of other groups, occurring in the same locality,
were firmly attached when they died.

Geological position, etc.: The same as that of the preceding-
species.

Our own collection.

ACTINOCKINUS ARNOLDI (nOV. sp.) W. «fc Sp.
PL XVII. Fig. 10. A somewhat flattened specimen with arms and column.

Of large size, with long, slender, spreading arms, and fan-like
fringes of pinnules. Form of calyx subovoid, gibbous below,
somewhat spreading at the arm bases.

Basal disk low, discoid, convex toward the margins, with
slightly retreating angles to meet the radials; flattened for the
attachment of the column, but without projecting rim.

First primary radials large, heptagonal; second hexagonal,
not more than one-half the size of the former; the third still
smaller. Secondary radials apparently small.

Arms six to the ray on the anterior side; long, tapering
abruptly toward the top and growing very thin. They are
composed of a double series of very short interlocking pieces,
with waving suture lines. In the lower and middle portion of
the arms, every third to fifth arm piece bears on the back,
close to the longitudinal suture, a small, sharp, hook-like spine,
pointing upward. Toward the upper part, the arms have more
or less serrate edges, and the plates overlap each other, form-
ing at the back small, pointed hooks.

Pinnules very numerous, long, slender, and in close contact as
if forming a reticulate fringe; each joint bearing a prominent
sharp hook, pointing at right angles to the pinnules. These
hooks, which run in 8 or 10 regular rows, parallel to the arms,
give to the mass of the pinnules, as they lie spread out, a
marked reticulate appearance.

Interradials five or more, comparatively large. The first
equal in size to the second radials, the two in the second range

CRINOIDS AND BLASTOIDS. 169

to the third radials ; the succeeding ones comparatively smaller.
Azygous interradius unknown and likewise the ventral cov-
ering.

The surface ornamentation of this species is different from
that of any other with which we are acquainted. The surface
of the plates is indented with numerous shallow polygonal pits
and short grooves, whose rims, which are somewhat rounded
off, connect with one another from plate to plate, and on the
same plate, in intersecting wrinkles. There is no very definite
arrangement of either pits or wrinkles, but the whole surface
has a somewhat irregular cancellate sculpturing, not unlike the
appearance of the parasitic Chastetes.

Column round, composed of very short joints of nearly uni-
form diameter so far as we have observed them, and alternat-
ing in thickness.

Geological position, etc.: Same as last.
Collection of Hon. Delos Arnold.

GENUS MEGISTOCRINUS Owen & Shum.
MEGISTOCRINUS NOBILJS (nov. sp.) W. & Sp.

PI. XVI, Fig. 6. A large specimen with arms.
P . XVI, Fig. 7. Another specimen. Ventral view.

Calyx large, broadly urnshaped, truncate at the bottom, with
deep constrictions or depressed areas at the brachial zone
between the rays and their divisions. Vault usually but little
convex, forming almost a plane, except along the azygous side,
which is more or less depressed, while the plates surrounding
the anal aperture are slightly elevated. The specimens are of a
light grey, intermediate between the lightest and darkest fossils
of this locality.

Basals comparatively small, resting within a shallow cavity,
produced by the bending in of the lower portions of the first
radials. They form a very regularly hexagonal disk, with a
conspicuous rim enclosing the upper stem joint. The plates are
closely anchylosed, and the interbasal suture but indistinctly
visible, while the basi-radial sutures are deeply beveled.

170 PALEONTOLOGY OF ILLINOIS.

Primary radials large ; the first and second hexagonal ; the
third or axillary one pentagonal. The lower portion of the
first radial and the interposed first anal plate somewhat
abruptly bent inward to form the basal concavity, while the upper
portions are slightly bent upward in such a manner that the
calyx rests upon the median portions of the plates. Second
radials somewhat smaller than the first, but much larger than
the third. Secondary radials 2x2x5, about as large as the pre-
ceding axillary. They support upon their nearly truncate upper
sides two rows of tertiary radials, of which, however, only the
lower ones take the form of radials, the others resemble closely
free arm plates.

Arms short, the tips bending inwards; bifurcating soon after
they become free, and two or three times above. At their
bases in the calyx the arms are very robust, but they diminish in
size rapidly from each bifurcation upwards. They are composed
of a double series of low transverse pieces, longitudinally
arranged, and alternating. The pinnules are closely packed to-
gether and composed of short joints.

Interradials 12 to 15 or more up to the arm bases, the lower
one as large or larger than the second radials, hexagonal, sup-
porting on its sloping upper sides two plates of the size of the
third radials; hexagonal or heptagonal according to whether
there are two or three pieces in the third range. The plates of
the third range resemble in size the secondary radials against
which they rest. They are of large size compared with
the plates of the upper ranges, especially those of the equa-
torial zone, which comprise the fifth and sixth ranges. Axygous
interradius much larger than the four regular ones. First
anal plate a little higher than the first radials, and narrower.
It supports three large plates, and above several other ranges
of considerably smaller pieces. There are six or more interax-
illaries, the lower one as large as the interradials of the third
range, the upper ones like the succeeding interradials.

Vault composed of slightly convex plates, almost of uniform
size. Summit plates a little larger ; continuous in mature speci-
mens; never separated by the intercalation of small plates.
They consist of a central piece and six proximals, of which four

CRINOIDS AND BLASTOIDS. 171

are placed over the four regular sides, and two over the azygous
one. \vith a radial dome plate interposed above each of the postero-
lateral rays. The arrangement of these plates is not correctly
represented in The figure. In two of our specimens, the ventral
covering of the arms is beautifully shown for quite a distance.
It consists of two rows of rather robust covering -pieces, form-
ing a well defined ridge, and there is at each side of them a some
what smaller row of side pieces. These four rows commence at the
edge of the vault, being continuous with it, and extend ap-
parently to the full length of the arms. It is the first instance,
to our knowledge, that side pieces have been observed in the
Camerata.

Column large, round, composed of alternate thicker and thinner
joints, with a large pentalobate axial canal, in which the lobes,
instead of being rounded, are angular.

Geological position, etc. : The same as in the last species.

Collection of Hon. D. Arnold, and our own.

MEGISTOCRINUS PARVUS (nov. sp.) W. & Sp.

PI. XV. Fig. 7. A fine specimen with arms and column. (One of the rays has excep-
tionally but two primary radials.)

A comparatively small species. Calyx bowl-shaped, with con-
vex sides, swelling regularly from the basals up. Arms long.
This species differs from the preceding one in the form of its
calyx, which is not impressed at the bottom, and in having
longer arms and a smaller column. Calyx plates convex, without
ornamentation; the suture lines well marked. The only two
specimens known to us are light in color.

Basals closely anchylosed, forming a low. almost flat disk.
Primary radials large, decreasing in size upwards. Secondary
radials 2x2x5. supporting ten primary arms. Arms biserial from
their base up. constructed of comparatively long pieces, longitu-
dinally arranged, the plates- alternating. The arms are long,
heavy, but decrease in size after each bifurcation. The two
proximal arm-plates, although regularly interlocking, form
generally a part of the calyx. Pinnules rather strong, composed
of joints twice as long as wide.

- 172 PALEONTOLOGY OF ILLINOIS.

Interradials ten to twelve to each area; the first one as large
as the third radials, or larger, the upper ones, which form a
shallow impression along the calyx, much smaller. There are
two plates in the second range, three in the third, and generally
two or three smaller pieces above. Interaxillaries three, small.
Azygous interradius much wider, consisting of three large plates
in the second range, three or four in the third, with several rows
above. The exact position of the anus is not known, but it evi-
dently was not placed laterally, as it cannot be seen between the
arm bases. Nothing is known of the construction of the vault.

Column and axial canal small for this genus. The joints near
the basals are all large, while further down long and short joints
alternate.

Geological position, etc. Same as the last species.

Our own collection.

GENUS BATOCRINUS Casseday.
BATOCRINUS MAC-BRIDEI (nov. sp.) W. & Sp.

PL XV, Fig. 4. Specimen with arms, column and cirrhi.

PL XVII, Fig. 12. Anterior side of another specimen.

PL XVII, Fig. 11. A side view of the calyx, from its anterior side.

This is the earliest and smallest known species of Batocrinus,
but it possesses all the characteristics of the genus. Height of
calyx and arms rarely more than an inch. The plates are but
slightly convex, and without ornamentation. Dorsal cup sub-
turbinate, broadly truncate at the base, with straight sides to
the arm bases. The vault is somewhat lobed, with a con-
spicuous depression toward the arm bases. The specimens have
a brownish color, much lighter, however, than those of Dicho-
crinus inornatus and Rhodocrinus kirbyi.

Basals forming a shallow cup, truncated at the lower end, and
excavated for the reception of the column. The plates are
rounded upon the surface; deeply beveled at theinterbasal sutures,
forming notches, two of which are occupied by radials, the third
by the first anal plate. The upper margins are excavated to re-
ceive the lower convex sides of the three other radials.

First primary radials one and a half times as wide as high, the
second short, quadrangular, more than twice as wide as high; the
third pentangular, not higher than the second but wider. Sec-

CRINOIDS AND BLASTOIDS. 173

ondary radials 2x2x5, the upper ones axillary; succeeded by two
cuueate fixed brachials, each supporting an arm, giving normally
four arms to the ray, or twenty in all. Arms biserial, moderately
strong, rounded, the tips slightly incurved and somewhat flattened.

Interradials rarely more than three, sometimes but two. The
first one very large, extending to the full length of first secondary
radials: those of the second range small. None of these plates
connect with the interradials of the vault, except those of the
azygous side, and therefore the plates forming the bases of the
arms are united laterally. The first anal plate has the form of
the first radials, and supports upon its truncate upper side
another anal piece, which rests between two large interradials.
All three plates are nearly of equal size, and as high, if not quite
as wide, as the corresponding single plate of the four regular
sides. There are two or three small plates above, and a single
piece between the arm bases. The interradials of the ventral side
are numerous, small, slightly convex. Ventral tube subcentral,
long, slender, extending beyond the tips of the arms. Ventral
side broadly convex, somewhat lobed; composed of numerous
small convex plates, among which the summit plates are well de-
fined, the central one forming the base of the tube.

Column short, the nodal joints in the upper part large, rounded
on the edges; the intermediate joints comparatively small and
short, contrasting strongly with the others. At the lower
end the joints are more uniform. The column has been ob-
served by us to its full length in several specimens, and in all of
them it is short, not to exceed six inches. It tapers all the way
gradually to its distal end, where it terminates in a sharp point.
The lower part, to about one-third of its whole length, bears
short lateral cirrhi, which are arranged singly, not in whorls, there
being but one to a joint.

Geological position, etc. The same as the preceding species.

Our own collection.

GENUS DORYCRINUS Roemer.

The three species of Dorycrinus herein described are very in-
teresting as illustrating the close affinities which exist between
B&tocrinns, Eretmocrinus and Dorycrinus, for which we pro-

174 PALEONTOLOGY OF ILLINOIS.

posed (Kev. of the Palaeocr., Pt. II, p. 96,) the group Bato-
crinites. If it was not for the fact that Dorycrinus immaturus
has but two arms in the anterior ray,* and Batocrinus mac-bridei
four, the two species could not be easily separated without see-
ing the posterior side of the calyx and the ventral covering.
The azygous interradius is much wider, and in the arm regions
forms a large gap between adjoining rays. At the four regular
sides, also, the interradials of the dorsal cup are continuous
with those in the vault, but the gap between those arms is much
smaller. Another small gap is found between the main divisions
of the rays; while the two arms comprising each division are
laterally connected with one another for quite a distance. The
pairs of arms are given off from a small bifurcating radial, each
arm having a separate ambulacral opening, but the openings
placed closely together. We allude to all these details to show
that Dorycrinus immaturus , and the two succeeding species from
the same horizon, have single arms, contrary to all later species
of Dorycrinus, in which, as a rule, two arms proceed from one
arm opening. The double-arm structure — two arms from one
opening — which we have observed only in the Batocrinites, was
introduced in the course of time from the single-arm structure,
as shown (Rev. of the Palaeocr., Pt. II, pp. 47-50,) in Bato-
crinus and Eretmocrinus, in which both forms are found fre-
quently side by side, and accompanied by most remarkable
transition forms.

A comparison of the Le Grand species writh those in the Bur-
lington and Keokuk limestones, reveals the fact, that the former
have but half as many arms as the latter. Among the species
of the two beds the arms are distributed fundamentally on the
same principle, those, however, of the lower horizon have single
arms, while the others have two arms from each arm opening.
Another differentiation between the species of the different hori-
zons is shown by the fact that in species of the Burlington and
Keokuk the arm joints are extended into lateral spines; while
in the Le Grand species the tips of the arms are merely com-
pressed and flattened.

* Since the above was written, we have found in a layer nine feet above the
main crinoidal bed a number of specimens of a variety of this species having uniformly
four arms to the anterior ray, but otherwise undistinguishable from it.

CRIXOIDS AND BLASTOIDS. 175

DOHYCRI.VUS IMMATURUS (nOV. 8p.) W. & Sp.

PI. XYII. Fig. 17. Posterior sides of a specimen with arms.
PI. XVII. Fig. 6. Another specimen, showing anterior side.
Pi. XVI, Fig. 5. The calyx, showing the position of the anal opening.

The specimens are below medium size, measuring from an inch
to an inch and a half to the tips of the arms. Dorsal sidi of
the calyx subturbinate with slightly convex sides; the lates
convex and without ornamentation. The vault is conical, some-
what flattened posteriorly. Color of the specimens rather dark.

Basals short, truncated, extending laterally beyond the limits
of the column; suture lines distinctly defined. First radials
comparatively large, almost as wide as high ; the lower margins
convex, the upper concave; upper corners truncated. Second
and third radials very short, not more than half the width of
the first, but twice as wide as high; the second quadrangular;
the third pentangular. Secondary radials 2x2x5; resembling in
form the two upper primary radials, but somewhat smaller.
The upper plates are axillary in the four lateral rays, where they
support 2x2 tertiary radials with two arms each ; in the anterior
ray quadrangular, with only one arm to each side, thus giving
18 arms to the species.

Arms biserial. arranged in groups around the calyx, and sepa-
rated interradially by small plates. There are no inter-axillary
plates although the main divisions of the rays are readily
identified. The two arms which constitute these divisions are
in four of the rays arranged in pairs, being connected laterally
by the proximal arm plates.

Interradials three in the dorsal cup, two of them at the
brachial zone, and others above. First iiiterradial very large,
extending beyond the limits of the third primary radials; twelve-
sided, and nearly as wide as high. The two plates above are
elongated, small, but larger than those succeeding them in the
vault. First anal much the largest plate in the calyx; sup-
porting three plates in the second range, which are nearly as
larg*-1 as the first regular iiiterradials: the middle one, or second
anal plate, smaller than the other two. These again are suc-
ceeded by several smaller plates forming a protruding subcentral
anus which is lateral, but placed above the arm bases.

176 PALAEONTOLOGY OF ILLINOIS.

Vault subconical, pentalobate; summit plates prominent, the
central one sharply tuberculous, showing a tendency to become
spiniferous.

Column round, composed of long joints with rounded edges,
which alternate near the calyx with very short and narrow
pieces.

Geological position, etc.: The same as the preceding species.

Our own collection.

Remarks : It is possible that this Kinderhook form is specifi-
cally identical with Dorycrinus (Actinocrinus) helice Hall from
the Waverly group of Ohio.

DORYCRINUS RADIATUS (nov. sp.) W. & Sp.

PI. XVII, Fig. 5. A specimen with arms from the posterior side.
PL XVII, Fig. 5a. The same from the 'anterior side.

Dorycrinus radiatus somewhat resembles D. immaturus, but
differs from that species in the arm formula, and in being the
only species of this genus which has radiating ridges along the
plates. From every first radial two low, rounded ridges pass
to the basals, two to the adjoining radials and anal plate, and
one to each first interradial. The interradials have nine ridges
two connecting with the first radials ; two with the second, and
two with the third radials, while the remaining three which are
smaller pass into the three interradials of the second range.
The ridges are well defined next to the margins of the plates,
but become indistinct, or disappear entirely, in the middle.
Color rather lighter than in the last species.

Dorsal side of the calyx subconical, wider than, high, truncate
at the base, a little convex along the sides. Basal cup short,
broad, with projecting lips, extending in width considerably be-
yond the limits of the column, and slightly beyond the lateral
walls of the calyx.

First radials somewhat lower than those of the preceding
species, the second and third radials proportionately a little
higher. The secondary radials vary among the rays, consisting
in the anterior ray, which has but two arms, of two com-
paratively large, transverse pieces, which are succeeded by
free, cuneiform plates, interlocking, and gradually turning into
two series of transversely arranged arm pieces. The other four

CRINOIDS AND BLASTOIDS. 177

rays have three arms each, with, exceptionally, four in one pos-
terior ray. In these rays the upper secondary radial toward
the posterior side is an axillary, and supports two arms, that
directed toward the anterior side quadrangular, with one arm
only. The arms are scarcely as long as those of the preceding
species: they are round and composed of medium sized pieces,
with straight transverse sutures.

The interradials dorsally consist of six to eight plates in three
ranges. The first plate is large, and extends to the top of the
third radials. There are three much smaller plates in the second
range, and two in the third, the latter resting between the arm

see. At the azygous side, the plates are arranged as in Dory-
crinus im ma turns. The first anal plate is as large as the first
radials. and the three succeeding plates fully equal in size to
the single plate at the four regular sides. The second anal
plate extends in height slightly beyond the level of the inter-
radials adjoining it. and is generally a little larger throughout.
This row is followed by several rows of smaller plates, which
lead to a subcentral anal opening. The arrangement of the
plates forming the vault is not known.

Geological position, etc.: The same as the preceding species.

Our own collection.

DORYCRLNUS PARVIBASIS (nOV. 8p.) W. & Sp.

PL XVII, Fig. 7. Specimen with arms from the anterior side.

PL XVn, Fig. 9. Lateral aspect of the calyx.

PL XVH, Fig. 9a. The same specimen, showing the ventral surface.

This species differs from the two preceding in the form and
proportionate size of the basals. and in the form of the calyx.
It is of the type of Dorycrinus concavus from the Lower Bur-
lington limestone, for which Meek and Wort-hen in Vol. II, of
this Report, p. 214. proposed the genus Ccelocrinus. This spe-
cies was supposed to have no secondary radials, and upon this
character principally, and a slight variation in the arrangement
of its interradial and anal plates, the new genus was founded.
With regard to the absence of secondary radials. Meek and
Worthen were evidentlv misled. On page 214. they say: "there
-23

178 PALAEONTOLOGY OF ILLINOIS.

being but a single brachial piece to each division of the ray,
soldered into the walls of the body, and these rest directly
upon the third radials." What else could these plates be but
secondary radials?

General form, without the arms, oblate-spheroidal, truncate
below. Dorsal cup in form of a basin which rests upon the basals
and portions of the first radials; wider than high, and spread-
ing but little at the sides. Plates moderately convex, without
ornamentation, suture lines well defined, with a small pit at
each angle of the plates. In color not distinguishable from D.
immaturus.

Basals forming a very small disk, resting in a shallow con-
cavity, not visible in a side view. First radials large, hepta-
gonal, narrow below and wide above, so as to present an ob-
tusely triangular aspect; the upper corners truncate; upper
margins concave to receive the second radials. Second and third
radials small, of about equal size. Secondary radials 1x2x5,
succeeded in the three anterior rays by fixed brachials. In the
posterior ray to ward the anal side the secondary radial is axillary,
supporting two rows of arm plates, thus giving twelve arms to
the species.

Arms biserial, with one or two cuneate joints succeeding the
radials, of which those of the same ray are laterally united.
The arms are proportionally more robust than in the two preced-
ing species, and resemble those of Agaricocrinus.

Interradials in three ranges; the first very large, reaching to
the top of third radials. It supports two long, narrow plates,
which extend to near the arm-bases, and by still smaller plates
in the vault. First anal plate larger than the first radials,
hexagonal, higher than wide; the second anal, and the two in-
terradials on either side of it, about equal in size to the first
regular interradial. They are followed by about four ranges of
small plates, which lead to a circlet of very minute pieces, sur-
rounding a subcentral protuberance with a small lateral opening.

Ventral side depressed, convex, summit plates nodose and
prominent; the central one large and projecting, in form of a

CRINOIDS AND BLASTOIDS. 179

small spine; the four regular proximals much larger than the
two at the anal side, which are separated from the former at
each side by a radial-dome-plate.

Column round, slender; composed near the calyx of alternat-
ing joints, the larger ones with rounded edges.

Geological position, etc.: Same as preceding species.

Our own collection.

180 PALEONTOLOGY OF ILLINOIS.

FAMILY MODOCRINID.E.

GENUS RHODOCRINUS.
KHODOCRINUS KIRBYI (nov. sp.) W. & Sp.

PL XV, Fig. 10. A specimen with infolded arms, and column.

PL XVI, Fig. 3. Another specimen with spreading arms, showing the pinnules.

This species is characterized by its barrel-shaped calyx, robust
arms for the genus, short arm joints, and rapid widening of the
arm bases up to the first bifurcation. The color of the speci-
mens is very dark.

Calyx elongate, truncate below; the sides nearly straight,
swelling but little from the lower edge of the basals on which it
rests to the top of the third radials, above which it contracts
rapidly, producing the form of a barrel. Some specimens are
almost cylindrical, about equal in diameter at top and bot-
tom. Viewed from above or below, the outline is obscurely pen-
tagonal.

Base sharply impressed. Underbasals small, resting in a shallow
concavity concealed by the column. Basals very large, their
lower margins sharply bent inward, forming the edge of a rim
on which the cup rests. Sutures distinct.

First primary radials much smaller than the basals; the
second and third about half as large as the first, and equal to each
other. Secondary radials 2x2x5, quadrangular, narrow, rising
above the surface in prominent ridges, which increase in width
upward. They are succeeded by three very short, transversely
arranged brachials, which also successively widen upward. The
upper one is axillary, giving off two branches. The inner branch
of the rays bifurcates again, generally on the third plate, thus
giving three arms alternately arranged to each main division

CRINOIDS AND BLASTOIDS. 181

of the ray, thirty in all, with occasionally an additional one in
one or both posterior rays. The arms are proportionately
heavier than in other species of the genus, but taper rapidly at
their tips. They are composed of a double series of very short
interlocking pieces, with deeply indented suture lines so as to
give to the back of the arms a file-like appearance. Pinnules
strong, continuous, composed of elongate joints.

Interradials 7 to 9 in four or five ranges; the first plate
smaller than the first radials. This is succeeded by two, rarely
three, plates of nearly the same size, and two or three ranges
of smaller plates. Azygous interradius wider and easily distin-
guished. It has always three plates in the second range, of
which the middle one is an anal, higher than the first radials
and fully as wide. There is a second anal plate in the third
range, which is but little more than half the size of the first.
Succeeding plates small and more or less irregular. Anal aper-
ture placed at the end of a very short, wart-like, somewhat
tubular and almost central protuberance, which is directed up-
wards, and surrounded by small spiniferous plates. The plates
at the azygous side are similar in proportion but greater in
number than at the other sides. Vault slightly elevated and
rounded, with small depressions toward the interradial spaces.
It is composed of numerous, very small tumid pieces, among
which the summit plates are with difficulty distinguishable.

Surface of plates convex or slightly angular, covered with
ridges passing from plate to plate. The ridges following the
radials pass into the arms, growing sharper and higher on
approaching the arm bases.

Column large, round, joints short, of uniform diameter; cen-
tral opening small, round or obscurely pentagonal.

This is one of the most characteristic species of the Le Grand
beds, and we take pleasure in naming it in honor of G. F.
Kirby, Esq., of Marshalltown, Iowa, the President of the Le
Grand Quarry Co.

Geological position, etc.: Same as the last species.

Our own collection.

182 PALEONTOLOGY OF ILLINOIS.

RHODOCRINUS NANUS Meek and Worthen.

PI, XVI, Fig. 4. Specimen with arms from the anterior side.

PL XVII, Fig. 15. Another specimen from another side.
1866, Meek and Worthen, Proc. Acad. Nat. Sci. Phila., p. 254.

1868, Geol. Surv. Ill, Vol. III. p. 476, PL 18, Figs. 2 a, b.

This species was described by Meek and Worthen in Vol. Ill,
of these Reports, p. 470, PI. 18, Fig. 2 a, b, from a single speci-
men without arms. It was found by one of us in the Kinder-
hook beds near Burlington, just above the oolitic layer, but by
mistake it was stated in the description to be from the Lower
Burlington. It remained unique until the Le Grand discoveries
brought to light a number of specimens, which apparently be-
long to the same species, and as they present the characters of
the species more fully, we have thought it best to redescribe it
briefly.

Rhodocrinvs nanus is nearest allied to A. kirbyi, from
which it is distinguished by its more globose form, more slender
arms, and these composed of longer and more uniform pieces,
as well as by the ridge-like series of anal plates. In the Le
Grand beds this species is readily identified by its color, which
is invariably light.

Calyx subglobose, sides regularly convex, except in specimens
with protuberant basals, in which the sides are nearly vertical.
Base truncate, slightly impressed.

Underbasals small, projecting but little beyond the column.
Basals large, sometimes protuberant, the cup resting on their
lower edges, which are rounded and form a low rim around the
shallow basal depression.

First primary radials nearly as large as the basals; second
and third about equal, and one-third the size of the first radials.
Secondary radials 1x2x5, followed by about five rounded quad-
rangular brachials of uniform size.

Arms bifurcating on the fifth joint, and the inner branches of
the ray once again on the third joint, with an occasional bifur-

CRINOIDS AND BLASTOIDS. 183

cation of the outer branch in a posterior ray, giving normally
6 ultimate arms to the ray, or 30 in all. The free arms are
biserial, slender, tapering very gradually; the arm pieces pro-
portionately longer and narrower than in Jt. kirbyi, and the
back of the arms more rounded and smoother. Pinnules strong,
not so closely packed as in the last named species.

Interradials 8 to 10; the first one half as large as the first
radials, and the two in the second range almost equaling it in
size. There are several more ranges of plates above, which are
irregularly arranged and decrease in size upwards. The anal
interradius is wider. It contains a row of anal plates, longitu-
dinally arranged, which rest upon the truncate upper face of the
first interradial, and extend up to near the anal aperture,
forming a kind of ridge, which is readily distinguished from the
surrounding slightly depressed interradial plates. The first anal
plate is as large as the first radials, the interradials on either
side of it smaller than the corresponding plates at the four
other sides. Anus excentric, protuberant, tube-like, composed
of rather large plates; opening directed upwards;

Ventral side rising somewhat above the dorsal cup, depressed
in the interradial spaces, and composed of small, irregular convex
pieces. Summit plates very indistinct, if represented at all.

The surface of the calyx is marked by rounded radiating
ridges, which are continuous along the radial series, and extend
into the arms. The ridges vary somewhat in prominence among
specimens, and in some are almost entirely confined to the
radial series, giving to the calyx a pentagonal outline ; while in
others they also pass to the basals, interradials and anals.
The plates as a rule are convex, and the suture lines well de-
fined.

Column small, round, composed of alternate joints; perfora-
tion small, apparently round.

Geological position, etc. : Kinderhook beds of the Lower Car-
boniferous, Le Grand ; also, Burlington, Iowa.

Our own collection.

184 PALAEONTOLOGY OF ILLINOIS.

RHODOCRINUS WATERSIANUS (sp. nov.) W. & Sp.

J3!. XVII, Fig. 16. Specimen with arms. Anterior view.

This species is of the type of R. wortheni Hall, (Geol. of Iowa,
1859, Vol. I, Pt. 2, p. 556), which is its nearest congener. It differs
from that species in its more concave base, the proportionally
smaller size of basals and first radials, and in its globose form .
All specimens known to us are light colored.

Calyx globose, truncate below, and slightly concave. Plates
decreasing in size from the basals up. The underbasals are small
and concealed by the column. The basals moderately large; their
lower end abruptly deflected inward, forming the rim of the basal
cavity on which the cup rests.

First primary radials slightly smaller than the basals. Second
and third plates still smaller, decreasing gradually upward.
Secondary radials 1x2x5, not more than half the size of the third.
They support a series of slightly cuneate arm joints, the fifth of
which is axillary. In the type specimen, and the most of those
observed, there is but one bifurcation, giving four ultimate arms
to the ray, or 20 in all, but we have observed specimens, probably
more mature, but otherwise not distinguishable, which have five
arms in place of four.

Arms rounded, slender, tapering gradually, the joints pro-
portionally longer and narrower than in R. kirbyi, and the pin-
nules stouter. The interradial areas are not depressed, but form
an even surface with the other calyx plates. They are composed of
about six plates, of which the first is a little more than half the
size of the first radials, the succeeding plates decreasing in pro-
portion to their rank. Azygous interradius occupied by a median
series of three or more comparatively large anal plates, which are
hexagonal, and bordered by interradials of about the same size
as the corresponding ones in the other areas. They are succeeded
by smaller plates extending up to the anal opening, which is small,
subcentral, protuberant, and directed upward.

Ventral side convex, abruptly constricted above the arm bases,
with no marked depressions in the interradial spaces. It is com-
posed of numerous small, smooth plates.

CRINOIDS AND BLASTOIDS. 185

Surface of the plates granular, but otherwise devoid of orna-
mentation: suture lines indistinct.

Column small, rounded, with a small axial canal. The specific
name is in honor of Dr. W. B. Waters, of Marshalltown. Iowa.

Geological position, etc.: Kinderhook beds of the lower carbon-
iferous. LeGrand. Iowa.

Our own collection.

23

186 PALAEONTOLOGY OF ILLINOIS.

FAMILY PLATYCRINID.E.

GENUS PLATYCRINUS.
PLATYCKINUS SYMMETRKTS (nov. sp.) W. & Sp.

PL XV, Fig. 8. Specimen with arms, column and root.

This species is of the type of P. burlingtonensis O. & Sh. (Geol.
Surv. Wisconsin, Iowa and Minnesota, 1852, p. 589,) and may
possibly be identical with some one of the various smooth species
that have been described from the Burlington limestone. Several
of these species were based upon specimens in which neither the
vault nor the arms were preserved, and from the meagre informa-
tion we obtain from mere descriptions of the basal and first radial
plates, it is not easy to identify them satisfactorily. Our species
differs from the P. burlingtonensis, as described by Owen and
Shumard, in having a proportionally smaller basal disk, longer
and narrower first radials; and from specimens identified by the
Burlington paleontologists as representing that species, it differs
in the form and structure of the ventral side, which in all Burling-
ton specimens is considerably elevated above the arm bases, and
occupied chiefly by the extremely large summit plates and the
base of a large anal tube. In P. symmetricus the ventral covering-
is low, to a large extent formed by rows of rather prominent cov-
ering plates, and the anus is represented by a simple subcentral
opening. It agrees with P. hurlingtonensis, however, in having
thirty arms. From P. pileiformis Hall, it differs in the vault
structure, in its truncate base, and, besides, that species, as shown
in our collection, has but twenty, and much heavier arms. The
new species bears a strong resemblance to an undescribed species
from the Lower Burlington limestone of New Mexico, not only
in the shape of the radials, but also in the proportionate size of
the basal disk, and the outline of the calyx generally. It agrees

S AND P.LASTOTDS. 187

in a marked degree with P. truncntiilus Hall, from tlie Lower
Burlington, i Inscribed in the Report on theGeology of Iowa, 1858,
Vol. I. Pt. '2. p. .~>:ix. and we should regard the two as identical, if
it were not for the fact that Hall's species has three primary
radials instead of two. as all other known species of the genus
with the exception of one from the Devonian, of New York. This
feature was indicated by Hall — Iowa Report, supra— who described
the second radial as of "quadrangular form, with a single groove
on the inside, showing that there was no bifurcation from this
plate." This was so great a departure from the normal type of
the genus, that we regarded it as an aberrant individual until re-
cently, when we obtained two specimens of that species with parts
of the arms preserved, which have a quadrangular second and
pentagonal third primary radial in every ray. This character
being thus apparently constant for the species, the LeGrand form
cannot be referred to it, and must be regarded as distinct.

The color of the specimens is very light, in marked contrast
with Rhodocriuus kirbyi and Dichocrinus iuormitns.

The species is of rather small size, its general form more
elongate than discoid ; the rays rising vertically in symmetri-
cal clusters, by equal divisions, from the upper portions of the
first radials.

Calyx cup-shaped or subturbinate. spreading uniformly to the
top of the cup; truncate below, with a slight elevated rim for
the attachment of the column; plates convex; interradial and
basi-radial sutures beveled and indented. Basal disk small, con-
vex, margins slightly concave, the plates so closely anchylosed,
that no traces of sutures can be discovered.

First radials a little higher than wide, increasing in width
upward; articular facets facing upward, and occupying a little
more than one-third the width of the plate. Second radials
triangular, sometimes pentangular, completely filling the facet.

Arms given off from the second plate above the second radial,
and on the inner branches again from the second plate above,
making six arms to the ray in equal divisions, or 30 in all.
Two or three joints above the last bifurcation are usually
cuiieate, in single series, and above these the arms are biserial,
rounded, slender, tapering gradually to the tips. Pinnules
strong, not in very close contact.

188 PALEONTOLOGY OF ILLINOIS.

Interradial plates of moderate size, resting on the corners of
the first radials. Anus in form of a simple subcentral opening
in the vault. The opening is very small, surrounded by a num-
ber of minute plates.

Vault depressed-convex, composed of small, smooth plates.
It is conspicuously marked by five strongly elevated ridges,
radiating from the center to the armbases. They are composed
of small covering plates, which in the two posterior rays ex-
tend to the central plate, but in the others rest between the
proximals. There are two proximals at the anal side, but ap-
parently no special anal plate, or, if present, it is not distin-
guishable from the other small plates bordering the anal open-
ing. Nearly the same structure is found in a specimen of P.
truncatulus, in which two of the rows of covering pieces, at
least, extend to the central plate.

Column short, large, rapidly twisted, composed of transverse
elliptic joints, as usually in the genus. It tapers to a point, and
near the end is provided Avith numerous short rootlets; which
taper in a similar manner. Perforation minute.

Surface of plates and arms smooth, without any ornamenta-
tion.

Geological position, etc. : Kinderhook beds of the Lower Car-
boniferous, LeGraiid, Iowa.

Collection of Wachsmuth and Springer.

PLATYCRINUS PLANUS Owen and Shumard (?).

PL XVI Fig. 8. A specimen with arms.

1860, Journ. Acad. Nat. Sci. Phila. (Ser. II.), Vol. II, p. 573.

1852, U. S. Geol. Surv. Wise., Iowa and Minn., p. 587, PI. 5a, Fig. 4.

1858, Hall. Geol. Surv. Iowa, Vol. II, Pt. II. p. 533.

1868, Meek & Worthen, Geol. Surv. 111., Vol. Ill, p. 467.

1873, Meek & Worthen, Ibid, Vol. V, PI. Ill, Fig. 5.

The specimen figured under the above name belongs to a type
not uncommon in the LeGrand beds. It is larger and more
elongate than the preceding species, and characterized by a
rather low, gently swelling subturbinate basal disk, above which

CRINOIDS AND BLASTOIDS. 189

the calyx is nearly cylindrical, expanding a little at the arm
The first radials are a third longer than wide, and their
upper margins generally of equal height, forming a straight
transverse line all around, without any truncation of the cor-
ners for the iuterradial plates. The articular facet is small,
rather shallow, facing upward, without any prominent rim.

Arms usually six to the ray. with some exceptions: long,
comparatively strong and with closely packed pinnules. The
plates are smooth and thin, sutures not indented. The basal
disk has a sharp prominent circular lip for the attachment of
the column, forming a part of the basal cup. although having
the appearance of an auchylosed upper stem joint. The basal
cup appeal's as a single plate, no traces of sutures being visible.
Vault uukown. Specimens all light colored.

The specimen figured is of about medium size, some being
considerably larger, others smaller. It has only 5 arms in three
of the rays, and the upper margins of the radials are not so
uniformly rectilinear as in most of the others, but otherwise it
fairly represents the form herein described.

Whether this is really P. planus is uncertain. The difficulty
arises from the confusion in which the literature of that species
is involved. Owen and Shumard described it in the report on
the Geology of Wisconsin, Iowa and Minnesota, p. 587, from
the Lower beds at Burlington as a thin plated, elongate spe-
cies, with subturbinate base, long radials with small and deep
articular facets, and the point of attachment for the column
slightly excavated. They figure on PI. 5a. Fig. 4, two speci-
mens : one of moderate size answering the description fairly well
except that there is no excavation for the column ; the other of
a very much larger form, which has been described by Prof.
Wortheu as P. pmtteni. They also speak of specimens having
been seen nearly two inches in diameter, which would be an ex-
traordinary size for any Lower Burlington Platycriuus. Hall,
in the Report on the Geology of Iowa. 1858, Vol. II, Pt. '2, p.
533. PI. 8, Fig. 6, figured and described the species with some
doubt as to the specific identity of his specimen. His figure
shows very plainly that he was describing a specimen of P.
halli Shumard. from the Upper Burlington, a very different

190 PALEONTOLOGY OF ILLINOIS.

form, with heavy plates and somewhat indistinct surface mark-
ings. Meek and Worthen, in Vol. Ill of this Report, p. 469,
PL XVI, Fig. f>, described and figured as P. planus a well pre-
served specimen with large, elongate calyx, of the form of P.
pratteni, having similar slender arms; and again in Vol. V,
PI. Ill, Fig. 5, they figured under the name of P. pJanus, but
without description, a good specimen having many diameters
in common with the form under consideration. The truth is,
there are probably several species of these elongate smooth
forms of I'lntycrinus. The plates of those in the Lower Bur-
lington are very thin and fragile, so that specimens in good
preservation are rare, and the vault is for the most part un-
known. More abundant collections will no doubt throw new
light upon their affinities, but for the present we are inclined
to think the form herein illustrated comes as near to the origi-
nal description of Owen and Shumard as any that have since
been referred to it.

Geological position, etc.: Same as the last species. Our own
collection. P. planus, as recognized by the Burlington Geolo-
gists, is a leading fossil of the Lower Burlington limestone, and
has been found at the various localities where that formation
is exposed. It has been collected by us in New Mexico, and we
have seen specimens from different places in Missouri.

GENUS DICHOCRINUS.

DlCHOORINUS INORNATUS (sp. nOV.) W. & Sp.

PI. XVI, Fig. 1. A specimen with arms, showing the posterior side.
PI, XVI, Fig. 2. The same from the anterior side.

This is the earliest Dichocrinus known to us from America,
and perhaps precedes any known from Europe, but nevertheless
it has all the characteristics of the genus. Dichocrinus inorna-
tus probably has its closest affinities with D. ovatus 0. &
Shum., which, however, is beautifully ornamented, the calyx,
and especially the radials, are more elongate, and the large anal
plate less constricted between the arm bases. It also resembles
D. simplex Shum., but the proportions of the plates in the two

AND BLASTOIDS. 191

species are very different, the basal cup in our species occupy-
ing one-third the height of the calyx, besides being deeply ex-
cavated for the reception of the column. />. moral us is a very
characteristic fossil of the locality, and is found in excellent
preservation. The color of the specimens is very dark.

Height of specimens, without the stem, ranging from an inch
and a quarter to two inches and a half in the larger ones.
Calyx subglobose, truncated at the arm regions: the sides curv-
ing very uniformly from the column to the arm bases. Larger
specimens comparatively more elongate than smaller on
Surface of plates devoid of ornamentation or any kind of mark-
ings, except the first radials have a small angularity following
the middle portion of each plate in a vertical direction, which
extends frequently into the basals. Sutures, although quite
distinct between the radials, not marked by indented lin>

The basals occupy fully one-third of the height of the calyx;
they form a rounded cup or basin, which, seen from above, has
a strictly hexagonal outline. Interbasal suture passing from
the posterior to the anterior side; frequently obscure.

First radials one-quarter to one-half higher than wide. Sides
slightly contracted at both ends, somewhat bulging at their
middle portions, and abruptly inflected toward the vault, which,
including the first interradials. lies in a plane at right angles
to tlie sides of the calyx. Facets for the attachment of the
higher radials above one-third the width of the plates. Second
radials small: twice as wide as high or even wider: upper and
lower sides convex: rounded like arm plates. Third radials a
little larger: triangular, bifurcating: upper angle very sharply
pointed, and the upper part bent inward so as to separate the
two divisions: the sloping sides of the plates concave. The third
radials support from each side a short quadrangular pi»
which, together with the preceding plates, form a part of the
calyx, being connected with their fellows by the intercalation
of interradial plates. They are succeeded by a cuneate free
plate, and again by two rows of interlocking arm pieces. First
anal plate about the size of the first radials, but more strongly
inflected towards the vault.

Arms biserial, two to each ray: about twice as long as the
height of the calyx or a little more; comparatively stout: grad-
ually tapering to their tips. The arm plates have parallel

192 PALAEONTOLOGY OF ILLINOIS.

upper and lower sides, and are of medium height. Pinnules ex-
tremely long, rather stout, closely packed together. They are
composed of from 10 to 15 cylindrical joints, about three times
as long as wide.

Interradials apparently five to each side, all forming a part
of the ventral surface, which is flat and placed on a level with
the inflected upper edges of the first radials. The first range
of interradials consists of three plates, two of them facing the
adjoining radial; the third placed between the two others.
There seem to be two, perhaps more, small interradials above,
meeting with the summit plates. The azygous side apparently
has 5 plates in the lower range, the middle one being an anal
plate. The summit plates — their exact arrangement could not
be ascertained — are scarcely convex, they form together a con-
spicuous elevation, from which six well defined ridges pass out
to the sides; five of them divide again and follow the arms, the
sixth one leads to the anal aperture, which is directed upwards
and excentric in position. The ambulacral ridges, those lead-
ing to the arms, are formed of irregular covering pieces, the
anal ridge by numerous convex or wrinkled plates. Between
the ridges are six depressions, four of them located above the
regular interradii, the two smaller ones above the azygous side.

The column of this species is not very long. From our ob-
servation in two specimens it varies from 9 to 10 inches. The
joints increase at first a little in width, but soon taper again,
until at the distal end the column runs to a fine point, giving
off at intervals a small, short cirrhus from one side only. The
joints throughout are very even, and the nodal joints can be
distinguished only along the upper part of the stem. Axial
canal minute.

Geological position, etc.: The same as in the last species.

Our own collection.

CRIXOIDS AND BLASTOIDS. 193

> [BORDER IX ADO AT A.

BRANCH FISTULATA.

FAMILY POTERIOCRIXID^E.

GEXUS GRAPHIOCRIXUS.

LONGICIRRIFER (nOV. 8p.) W. & Sp.

PL XY, Fig. 12. Specimen with arms, from the anterior side.
PI. XTII, Fig. 14. The same from the posterior side.

This species is of the type of Graphiocrinus (Scaphiocrinus)
wachsmuthi (M. & "W.). and Graphiocrinus (Scaphiocriuus) spino-
brachiatus (Hall), but differs from both in having cirrhi along
the upper portions of the stem. Besides, the former has a de-
cidedly bell-shaped calyx — the upper part of the radials flanging
outward : also the brachials are much less constricted, the suc-
ceeding: arm plates considerably higher, and the outlines of the
arms less waving. G. spinobrachiatus has a more depressed
dorsal cup. the underbasals are covered by the column, it has
stouter arms, and these are covered with small spines. The
specimens are always of a light color.

Calyx short, depressed, saucershaped, with slightly convex
sides; scar for the attachment of the column but slightly im-
pressed. Uuderbasals. although small as in almost every other
species of Graphiocrinus, extending slightly beyond the limits
of the column. Basals large ; four of them hexagonal, about as
wide as high : that of the azygous side considerably larger and
heptagoual, supporting upon its truncate upper face a large
anal plate, which extends far beyond the top of the radials,
and actually forms a part of the ventral tube. There is no
az3'gous plat P.
—24

194 PALAEONTOLOGY OF ILLINOIS.

Radials once and a half as wide as high, and about of equal
size, but differing somewhat in form although all are penta-
gonal; the two facing the anal piece, owing to the greater
length of the posterior basal, irregular. The upper face of the
radials, throughout the full width of the plates, truncated and
slightly concave. Brachials one, of the same height as the radials ;
pentangular, but subtrigonal in outline, upper angles sharply
pointed; line of articulation toward radials and also first arm
plates widely gaping.

Arms ten, long, moderately stout, gradually tapering. They
are composed of rather short, sharply cuneate pieces, which at
the upper margins form a thickened rim, which projects beyond
the lower end of the succeeding joint. The rim increases grad-
ually in prominence in the upper parts of the arms, especially
at the pinnule-bearing side of the plates where it bulges out
considerably, giving to the arms their characteristic zigzag ap-
pearance. The proximal arm plates, next to the brachials, are
longer than the succeeding ones, at their lower face as wide as
these, and somewhat constricted along their middle portions;
the others are at their longest side about equal to their width.
Pinnules long, and close to the arms very strong. They con-
sist of about ten joints, of which the proximal ones are short,
the others from twice to three times their width.

The form and size of the ventral tube is not known, near its
base it is composed of longitudinal rows of very regularly
arranged hexagonal pieces.

Column small, indistinctly pentangular ; nodal joints consider-
ably higher, especially the lower ones, and projecting laterally.
Each nodal joint, from the calyx down, gives off radially sev-
eral cirrhi, which are long, slender and directed upward. Near
the calyx where the nodal joints come very close together, the
cirrhi are so tightly packed that they frequently hide the
column, and extend beyond the calyx to the arms. Farther
down the column they are wider apart, and reach a length of
an inch and a half or more, while their length above is not
more than an inch. They are composed of numerous short
joints, and end in a sharp point.

Geological position, etc.: The same as the last.

Our own collection.

CRINOIDS AND BLASTOIDS. 195

GENUS SCAPHIOCRINUS Hall (emend. W. & Sp.)

SCAPHIOCRINUS ELEGANTTILUS (nOV. Sp.) W. & Sp.
PL XVII, Fig. 13. A beautiful specimen with arms and portions of the stem.

This small and elegant Crinoid resembles very closely Scaphio-
crinus nanus M. & W. from the Lower Burlington limestone,
and perhaps should only be considered a variety of that species.
The Burlington form, however, differs in having a more de-
pressed calyx, larger underbasals and higher brachials.

The LeGrand specimens are always light in color.

Calyx turbinate, the sides very slightly convex ; a little wider
than high; without ornamentation. Underbasals projecting be-
yond the column; the upper angles turned upward to meet the
basals. Four of the basals are hexagonal, about as wide as
high, the fifth one heptagonal, and larger throughout. Radials
but little larger than the basals, and almost as high as wide;
the upper face truncated throughout the width of the plates.
Brachials one to the ray ; axillary ; nearly twice as high as the
radials; obtusely angular for the reception of the first arm-
joints; not constricted in the middle, and, when the arms are
closed, their lateral faces almost meeting with those of their fel-
lows from adjoining rays.

Arms dividing once from the brachials up, the division taking
place generally from the sixth plate. The arms are com-
paratively strong, waving in outline, and composed of cuneate,
slightly convex and rounded pieces, about as high as wide or
nearly so. Pinnules very conspicuous, long, unusally stout,
and composed of cylindrical joints twice as long as wide. Azy-
gous side exceptionally wide. The posterior basal extends to
one-half the height of the radials, and supports upon its trun-
cate upper side the anal plate, which to a large extent forms a
part of the ventral tube. The azygous plate, to the right of
the anal plate, is also unusually large, pentagonal, and extends
very nearly to the top of the right postero-lateral radial,
although that plate, as in most of the Poteriocrinidae, occupies
a higher level than the radials of the other rays.

196 PALEONTOLOGY OF ILLINOIS.

The column, as observed in two specimens, is from 4 to 5
inches long. It tapers gradually from the calyx down, and ter-
minates in a fine needle point. It is round, and composed of
rather long segments, the nodal joints more prominent. Only
the lower portions of the stem, for about two-thirds of its
length, are cirrhus-bearing. The joints which bear the cirrhi are
higher than the intermediate ones, and while increasing in length
they decrease in width downward; the cirrhi are given off singly,
and are directed upwards, contrary to those of the preceding
species which hang downward; they are long, threadlike and
taper at their ends.

Geological position, etc.: The same as that of the last species.

Our own collection.

SCAPHIOCRINUS GLOBOSTJS (nOV. Sp.) W. & Sp.
PL XVII, Fig. 8. A specimen of unusually large size.

A small species. Calyx semi-globose ; the plates without orna-
mentation or convexity.

Underbasals minute, resting within a concavity formed by the
basals; rounded at their lower end; covered completely by the
column. The basals are comparatively large; four of them
regularly pentagonal, the fifth somewhat larger and hexagonal,
supporting upon its truncate upper face the anal plate.

Radials short, twice as wide as high. Brachials triangular,
meeting their fellows of adjoining rays; the two sloping upper
sides forming an acute angle; each side supporting from four
to six arm-plates of a second order, the upper one axillary.
There are two more branches above, making four arms to each
ray, the anterior one being not distinct. They are composed of
strongly wedge-shaped pieces, slightly swelling toward their
larger end; the axillaries more prominent. Pinnules strong;
tubular.

Anal plate larger than the azygous piece; ventral sac unknown.
Column unusually small, round, its diameter less than that of
the arms near their tips.

Geological position, etc. : The same as the last.

Our own collection.

CRINOIDS AND BLASTOIDS. 197

SUBORDER ARTICULATA.

FAMILY ICHTHYOCRINID^.

GENUS TAXOCRINUS.
TAXOCRINUS FLETCHERI Worthen.

PL XV, Fig. 6. A specimen with arms and stem.

PL XV, Fig. 9. Another specimen from the posterior side.

1883, Worthen. GeoL Rep. Dlinois, VoL VH p. 308, PL XXX, fig. 2.

Of about medium size ; rather short for its width ; arms stout,
short, closely folded together. The nature of the arms, and
still more the unusual size of the stem, gives to this species
that solid and robust aspect by which it is characterized, and
readily distinguished from all other species of this genus. The
specimens which we examined are all light in color.

Underbasals entirely covered by the column, and also por-
tions of the basals. The exposed parts of the latter are penta-
gonal, twice as wide as high, obtusely angular above, except
the posterior plate which is slightly truncated. The basals,
together with the first and second primary radials, form a
conical cup with broadly truncate base.

Primary radials three, transversely arranged, increasing in
width upward; their lines of articulation, like those of the
succeeding orders of radials and all arm-plates, strongly undu-
late, with short but wide patelloid pieces* interposed between
them. The first and second plates are about twice, and the
third three times as wide as high. The third radials, which

*The patelloid pieces, although well defined in the specimens, were omitted in the
figures.

198 PALEONTOLOGY OF ILLINOIS.

are axillary, are sharply angular at their upper faces, and pro-
vided with two articular facets and two impressions for the
reception of patelloid plates. Secondary radials three; by one-
half narrower than the preceding ones, and somewhat shorter,
but not in proportion to the decrease in width, except the
axillary one, which is comparatively shorter and also wider.

The next order of plates consists variously of from 3 to 5 or
6 pieces, with another bifurcation above. These plates are all
arranged on the plan of the primary radials, like them they are
flat at their outer sides, and united in a similar manner as
those, which makes it difficult to ascertain the actual com-
mencement of the arms. This difficulty is increased by the
fact that the rays are free from the top of the primary
radials, while their main divisions remain united all along the
secondary radials by means of interaxillary plates. Perhaps
these rays formed a kind of free appendage like those of the
Platycrinidse and Hexacrinidse, a question, however, which can-
not be solved unless we find the ventral covering intact.

Interradials three; elongate; the two upper ones much smaller,
extending to the top of the primary radials. There are gener-
ally three somewhat smaller interaxillaries, arranged longitu-
dinally, which unite the secondary radials. Smaller specimens
have but one or two. The azygous side is composed of a row
of from 3 to 4 or more tube-like anal plates, longitudinally ar-
ranged, which rest upon the truncate upper face of the poster-
ior basal. There are no traces of interradials to connect these
plates with the radials.

Column extremely stout, almost large enough to support a
species of twice the size of this. It is inflated near the calyx,
and, along the upper part for about an inch, is composed of
rather short, very uniform joints, wrhen suddenly the aspect of
the column changes entirely, the joints, at their margins,
become more convex, and larger and smaller joints alternate
with one another, the larger ones extending conspicuously be-
yond the smaller ones.

Geological position, etc. : The same as that of the last species.

Our own collection.

CRINOIDS AND BLASTOIDS. 199

TAXOCHIXT s IXTERMEDIUS (nov. sp.) W. & Sp.

PL XV. Fig. 11. A fine specimen with arms and stem.

A transition form between Onychocrinus and Taxocrinux, but
apparently nearer the latter: larger than the preceding species;
in its usual condition, with the arms bent inward, wider than
hi.irh. The rays widely divergent: the arms so long that their
incurved tips hang down to the top of the primary radials.
Color of specimens comparatively light; the plates devoid of
ornamentation.

['nderbasals three, unequal; the smaller one placed in a ver-
tical line with the right postero-lateral radial: almost completely
covered by the column, there being only a small rim exposed
laterally.

Basals large, subequal in size; regularly pentagonal: forming
a shallow cup. with five salient and five reentering angles.

Radials four in four of the rays, five in the right postero-
lateral one (constant in both specimens); wide but compara-
tively short for the genus, about three times as wide as
high, the upper and lower plates somewhat wider and pro-
portionately higher; the axillary one with obtuse upper angles.
Secondary radials three, a little more than half the width of
Thf preceding plates: the lower ones laterally connected in the
same ray. but not with their fellows of adjoining rays: the
second separated by three interaxillaries; the third free, widely
apart. Third order of radials variously composed of from 3 to
5 plates, of similar proportions to those of the preceding
orders, with one or three small interbrachials between the second
plates: the succeeding radials free. There are apparently three
more divisions above, the proximal plates above each bifurca-
tion connected laterally, the upper ones free.

All articular lines between the radials of the first and second
orders undulating, owing to the presence of short but wide
patelloid pieces: the lines between the succeeding plates straight,
the patelloid pieces either being absent or very minute.

The interradial plates can be traced in both specimens to the
ventral side: they are very interesting as throwing light upon
the ventral covering of the Ichthyocrinidae generally. In four of
the interradii, interposed between the primary radials, there are
five to seven comparatively large, slightly convex plates vari-

200 PALEONTOLOGY OF ILLINOIS.

ously arranged; the lower one which is larger generally
deeply wedged in between the first radials, so as to almost
touch the upper angles of the basals. There are two, three or
four plates in the second range, which abut laterally against
the adjoining second and third radials, and these are succeeded
by 4 or 5 plates of a third row, which are abruptly bent inward
at their upper ends almost at right angles, so as to form a
sharply defined edge, against which the plates of the ventral
covering rest. The latter plates are very minute and irregular
in their arrangement, they form a pliable integument, which prob-
ably extends over the whole surface and along the rays. The
free rays at their ventral side are provided with large pouches
which apparently contain the ambulacra. At the azygous side
the arrangement of plates is very different; the posterior basal
is shorter, truncated instead of angular, and excavated at the
upper end for the reception of three or more anal pieces, which
are longitudinally arranged and connected with the radials at
each side by small plates.

Column stout; slighely tapering; its upper end composed of
very short and even joints, all of equal size and prominence.

Geological position, etc.: The same as the last.

This is probably the rarest species at LeGrand, only two spe-
cimens having been found; that figured is from the collection
of Hon. Delos Arnold, the other in our possession, being
kindly presented to one of us by Mr. George Cull, the station
agent at LeGrand.

CRIXOIDS AXD BLASTOIDS. 201

CLASS PELMATOZOA.
ORDER BLASTOIDEA.

FAMILY CODASTERID.E.
GENUS OROPHOCRINUS.

1864. Orophocrinus, Von Seebach. Nachr. k. Gesellsch. zu Gottingen, p. 100.

1879. Orophocrinus, Zit;eL Handb. d. Paheont I, p. 434.

1882. Orophocrinus, Ether, and Carp., Ann. and Mag. Nat. Hist (Apr., 1882), p. 249.

1883. Orophocrinus, Ether, and Carp., Ibid. (Apr., 1883), p. 226.

1885. Orophncrinns, Wach«muth, GeoL Rep. Illinois. VoL VH, p. 317.

1886. Orophocrinus, Ether, and Carp., Blast. Catalogue, p. 2S3.

Syn. Pentremitfs. (in part) Munster.1839, Beitrage z. Petrefactenk, p. 1 ; also DeKoninck
and Lehon, 1853, Recherch. sur les Crin. du Terrain Garb, de laBelgique, p. 189; also Owen
and Shumard, 1&52. GeoL Rep. of Wise., Iowa and Minn., p. 333.

When Meek and Worthen. in 1869, proposed the name Codo-
nitvs for Owen and Shumard's Penti-emitf*$ st^lliformis and their
new species f'\ ^j\-n-i]is. they were not aware that Von Seebach
had previously proposed for the former the <jenus Orophocrinus,
which, having- priority, must be accepted. Since then Etheridge
and Carpenter have placed under Orophocrinus several Euro-
pean species, which had likewise heretofore been referred to
Pentremitee.

OROPHOCRIXUS roxirrs (nov. sp.) W. & Sp.

PI. XV, Fig. 1. Specimen with the pinnules and part of column preserved.
PL XV, Fig. 2. Another specimen, profile view. Enlarge 1 two diameters.
PL XV, Fig. 3. The same specimen from the ventral side. Enlarged as above.

This and the succeeding species are readily distinguished from
all othpr known species of this genus by their more slender
-25

202 PALEONTOLOGY OF ILLINOIS.

form, resembling therein Troostocrinus and Met&blasiw.
O. conicus differs from O. fusiformis in the form of its ventral
side, which is hemispherical, in the latter conical. Besides it
has shorter ambulacra, and a less number of pinnules.

O. conicus has the form of an elongate inverted cone with
nearly straight sides; ventral side depressed, hemispherical.
Surface of the plates smooth, or in well preserved specimens
marked by indistinct concentric lines around the plates. Basal
portions occupying more than two-fifths of the general height
of the calyx, or fully one-half the length up to the radial lips.
Neither the interbasal nor basi-radial sutures are marked
by any sort of identation, and both are therefore rarely observed;
The interradial sutures, however, are slightly depressed, especi-
ally along their upper portions, where they form an obtuse re-
treating angle, thus giving to the section across the lips an
obscurely stellate outline.

Radials or forked plates almost twice as wide as high; their
lateral faces nearly parallel; the lower sides in the three plates
facing the interbasal sutures angular, in the two others rounded.
The limbs of the radials extend to about one-half the length of
the ambulacra; they bend inward, and leave a comparatively
wide radial sinus.

The interradials or deltoids are partly visible in a side view;
they are double-diamond shaped, constricted along the middle,
so as to appear almost like two separate plates. The plate at
the azygous side is slightly bulging, pierced by a large elliptic
anal aperture, which in three of our specimens is completely
closed by a disk, composed of a large number of very minute
irregular pieces, which rest somewhat deeper than the surround-
ing plates, leaving no trace of an opening. The oral opening is
sharply pentangular and moderately large — much larger than
in O. stelliformis. It is covered in perfect specimens by com-
paratively large, very regularly arranged summit plates, con-
sisting of a central piece, and four large and two smaller proxi-
mals, from which irregular rows of covering pieces extend to
the ambulacra, arching over the food groves.

Ambulacra short, more or less petaloid, only partly visible in
a side view. They extend laterally to the slit-like openings or
clefts, and present an even surface with the surrounding calyx

CRINOIDS AND BLASTOIDS. 203

plates; being neither - elevated nor depressed. The lancet piece
extends to the sides of the radial sinus ; it is rounded along its
outer face, forming a longitudinal groove at each side, at the
bottom of which the clefts are placed. The lancet piece is
completely covered by the side pieces, which embrace the food
grooves, except near the oral center, where the grooves grow
deeper and are placed between the edges of two adjoining del-
toids. There are about fifteen side pieces to each side of the
ambulacrum, and an equal number of pinnules, but no pores
exist along the sides. The clefts are formed between the ambu-
lacra and the constricted portions of the deltoids, and hence do
not extend to the full length of the ambulacra. The clefts are
wider at their proximal end, and slightly curved, wrhich gives to
the ambulacra their petaloid form, The pinnules are longer
than those of any previously described Blastoid, their length
being twice that of the calyx. They are of uniform thickness
throughout, and composed of two rows of pieces, alternately
arranged. Their ventral furrow is wide and apparently covered
by small plates.

The column has been observed by us to a length of seven
inches, and was apparently much longer. It is stout close to
the calyx, whence it tapers rapidly; afterwards it remains nearly
uniform, with a few scattering cirrhi toward the end. The stem
joints at the upper end are extremely short, with a very sharp
edge, but they gradually grow longer and cylindrical.

Geological position, etc.: The same as the last.
From our collection.

OROPHOCRINUS FUSIFORMIS (sp. nov.) W. & Sp.

PI XVII, Fig. 4. A fine specimen having its pinnules preserved, and portions

of the stem.

Calyx elongate, biturbinate. Dorsal side up to the radial
lips, longer than wide; angular radially; the sides undulating;
the lips projecting. Ventral side, from the radial lips upward,
nearly as long as the dorsal, but the sides convex, curving
gently. Cross section through the radial lips decagonal, with
five salient and five retreating angles, and this is the case, to a

204 PALEONTOLOGY OF ILLINOIS.

less extent, from the deltoids down to about half the height of
the basals, giving to the species an angular outline, by which
it is readily distinguished from 0. conicus.

The surface ornamented with delicate concentric lines, finer
than those of the preceding species. The specimens are light in
color.

Basals nearly as high as the radials to their lips; forming
jointly a subconical cup with slightly convex sides; angular
above for the reception of the radials ; two of the upper faces
moderately concave, the other three angular.

Forked plates or radials elongate ; the prongs or limbs nearly
as long as the handle or bod}^; width across the lips almost
twice as great as at the two ends; the lateral faces as well as
their outer face gently and uniformly curving upwards and
downwards; the median line toward the sinus somewhat angu-
lar; the lips projecting, flanging outward so as to give to the
calyx up to the lips a reversed bell-shaped form. The sinus is
longer than in the preceding species, increasing in width up-
ward; its edge distinctly beveled. Interradial and basi-radial
sutures well defined.

Deltoids long, about as high as the basals, the upper sides
deeply constricted near their upper end for the admission of a
large spiracle; the lower sides less than half the length of the
upper.

Ambulacra long, somewhat wider than usual in this genus;
their sides almost parallel except at the distal end. They occupy
fully one-half the length of the calyx, and rest deeply within
the radial sinuses, which have steep sides, Lancet pieces visible
throughout their full length; the exposed part at the proximal
end equal to one-third the width of the plate. Food grooves
deep, especially near the mouth, however, when closed by covering
pieces these form conspicuous ridges, which extend inward as
far as the summit plates. Side pieces with a well marked
tubercle in the direction of the lancet piece, and superficial
grooves toward the pinnules, which rest within shallow pits.
The pinnules are composed of single joints, rather flat, scale-
like, upper and lower faces undulating. There are ten groups

CRINOIDS AND BLASTOIDS. 205

of hydrospires, eight to each group. The spiracles are reduced
to an elongate slit-like opening, wider above than below, not
visible when the pinnules are in situ, but quite conspicuous when
these are wanting, large enough that we could observe at the
bottom of two of them the clefts of four and six hydrospires
respectively. Anal opening very narrow, decidedly slit-shaped,
and strictly lateral.

Geological position, etc. : The same as the last.

The figured specimen is in our own collection : the description
of the ambulacra and hydrospires was made from a beautiful
specimen kindly presented to us by Prof. W. H. Harris, which
we received too late for illustration.

March. 1887.

P. S. This paper was placed in the hands of Prof. Worthen
early in the spring of 1887, before we had made the discovery
that the so called "central plate" and the four "proximals" at
the summit of Blastoids and Crinoids represent the orals, and
this accounts for the fact that the old terms are used in the
descriptions.

206 PALEONTOLOGY OF ILLINOIS.

A NEW GENUS FROM THE NIAGARA GROUP OF
WESTERN TENNESSEE.

ALLOCRINUS. (nov. gen.) W. & Spr.

"A A A. o s another ; H p i v o v a lily.

AHocrinus belongs to a group of Crinoids which is sparsely
represented in America, but of which several genera and a num-
ber of species are known to have existed during the Upper
Silurian period in Sweden. It belongs to the Camerata, family
Melocrinidte, division Stelidiocrinites. Its closest affinities are
with Patelliocrinus and Dolatocrinus. It differs, however, from
both of them in the form and size of the various calyx plates,
in the arm structure, and in the column. The genus is most
remarkable for its regularly pentamerous symmetry and
uniserial arms.

Generic diagnosis. Calyx small; the arms very stout. Sym-
metry of the dorsal side strictly equilateral. Basals probably
three; small; almost completely covered by the column. Primary
radials 3x5 ; the first very large ; the other two much smaller,
rounded along their outer face so as to appear like arm plates.
Secondary radials two or three ; rounded ; quadrangular. Arms
strong; uniserial; composed of large transverse plates. Inter-
radials two or more, large, deeply impressed between the
radials. Column small, round, with a rather small pentangular
central canal.

CKLVUDS AND BLASTOIDS. 207

ALLOCRLMS TYPCS (nov. sp.) W. & Sp.

PI. XIV, Fig, 7. A specimen with arms.
PL XIV, Fig. 7 a, b. Calices of the same.

Below medium size. Calyx depressed, very small, without or-
namentation: the arms massive, comparatively stouter than
those of any other Crinoid known to us. Basals small, almost
covered by the column; disk-like, bending neither inward nor
outward; suture lines indistinctly marked. First priniar3r
radials large, abruptly curved, the lower portions forming an
inverted shallow basin, of which the basal disk forms the
bottom part. The upper half of the plates is bent upward, and
forms, together with the other plates of the calyx, a shallow,
somewhat spreading cup with straight sides, resting on the pro-
jecting median portions of the plates. The second and third
primary radials have almost the form of brachials, but are con-
nected laterally by interradials. They are very short and rest
upon the first radials in a similar manner as the brachials of
the Cyathocrinidae upon their radials, and, owing to the deeply
depressed interradial spaces and the peculiar form of these
radials. it looks as if they were free plates.

Arms ten, uniserial: composed of transverse pieces of a similar
form but larger than the preceding radials. and like them with
parallel upper and lower faces. The arms are much wider mid-
way. than at the two ends, tapering considerably, and uniform-
ly toward the tips, and in the same proportions toward the
first radials. where the arms actually commence.

The interradial spaces are deeply depressed; they are com-
posed of two large plates, vertically arranged, of which the first
piece is smaller and nodose, and extends to the top of the pri-
mary radials, while the other rests between the secondary
radials and forms, to some extent, a part of the ventral sur-

208 PALAEONTOLOGY OF ILLINOIS.

face. There is no anal plate, and nothing is known of the anal
aperture nor of the summit structure.

Column small, round; axial canal pentangular, the angles
directed interradially.

Geological position, etc. From the age of the Niagara group
of Eastern Tennessee. The original is from the collection of
Prof. A. H. Worthen, and was found by him at Clifton, Wayne
Co., Tenn.

PART II.

PALEONTOLOGY OF ILLINOIS,

SECTION III.

AMERICAN PALAEOZOIC SPONGES.

BY E. O. ULRICH.

—26

SPONGES. 211

AMERICAN PALEOZOIC SPOXGES.

Although the spongia? attained the height of their develop-
ment in Mesozoic and subsequent eras, they were also very nu-
merously represented in palaeozoic times, in fact, much more so
than is generally known or suspected. As a rule they cannot
be considered common fossils, and, generally, belong to the
rarities. There are, however, several notable exceptions, such
as the Dictyophyton layers of the Chemung in New York, the
Astrlospongia beds in the Niagara of Tennessee, and the more
recently discovered sponge layer near the base of the Trenton
in northern Illinois, which has delivered up to the untiring
efforts of Dr. Oliver Everett, of Dixon, 111, the most varied and
interesting collection of sponges so far discovered in America.
The author, too, has during the last ten years, diligently
searched the lower rocks for remains of these long neglected
fossils. The material found was carefully preserved, and, since
the publication of Prof. ZitteFs sj^stem of classification, much
time has been spent in the attempt to work out the microscopic
structure. Owing to the poor state of preservation, the at-
tempt often proved quite unsuccessful, yet on the whole the re-
sults were satisfactory. They seem to establish, that the ma-
terial at hand from horizons below the Devonian represents no
less than thirty-four genera.* Of these, twenty-two have been
described: Protospongiti by Salter; Arch&ocyathus, Calathium,
Eospongia, Trachyum, Trichospongia and Avlocopina by
Billings: Aulocopium by Oswald; Brachiospongia by Marsh;

* Including ArchceocyatJnis and Ethmophy Hum, two genera that may not be true
sponges, certain features of their structure, lately pointed out. seeming to indicate a
closer relationship with the corals.

212 PALEONTOLOGY OF ILLINOIS.

Ethmophyllum by Meek; Astylospongia, Palaeomanon and As-
trasospongia by Koemer; Hindia by Duncan; Pattersonia and
Dystactospongia by S. A. Miller; Leptomitus and Cyathophycus
by Walcott, Astroconia by Sollas; Cyathospongia, by Hall;
Lepidolites, by Ulrich; and Climacospongia, by Hinde. The
twelve generic groups remaining, appear to be new to science.
No doubt it would have enhanced the value of this report had
it been possible to define all of them at this time, but a lack
of space, but more especially, the unwillingness to describe them
without proper illustration, necessitated a restriction to ma-
terial occurring within the limits of the State, or contained in
the State collection. In consequence, only six of the twelve new
Cambrian or Lower Silurian genera are defined in the following
pages.*

The Devonian and Carboniferous deposits have been much
less carefully searched, but the diversity of the fragments ob-
tained, indicate that these organisms were not less prolific in
those ages than in Silurian, Cambrian and Taconic times.

A few introductory remarks upon the preservation, geological
distribution, and classification of palaeozoic sponges, may prove
of interest to students, and it is hoped that our humble efforts
to bring this neglected branch of our palaeozoic fauna before the
scientific world will stimulate other collectors to an apprecia-
tion of their value.

PRESERVATION.

The structure of the sponges of the Palaeozoic rocks, the same
as of those from Jurassic and Cretaceous horizons, was often
so much altered during the process of fossilization, that it is
sometimes extremely difficult to determine its original nature.
The mineral constituents of the spicules are apparently never
the same as in the recent state, though the extent of the
changes varies greatly. The least alteration is where the origi-
nally amorphous silica, or calcite, has been changed into the
crystalline form of these minerals. The change most frequently
met with consits in the substitution of crystalline calcite for

* Since writing the above, the author has published descriptions of the other new
genera in the April, 1889. number of the "American Geologist." The names applied to
them are Havffella, Leptopoterion, Heterospongia, Saccospongia, and Cylindroccelia.

SPONGES. 213

the silica. At other times the silica is replaced by the peroxide
of iron, or, more rarely, by iron pyrites. On the other hand, a
few instances have been noticed where the original calcite has
been completely, or only partially replaced by siliceous ma-
terial.

Another condition, in which the mineral substance of the
sponge has been entirely dissolved and removed, leaving the
empty moulds of the spicular mesh in the matrix, is not un-
common, but more frequent in specimens from Upper Silurian
than other deposits.

As stated, the most common change in the mineral substance
of the sponge skeleton is the replacement of silica by calcite.
Examples of this replacement occur in all the great geological
divisions, but seem to be confined to calcareous and shaly de-
posits. The calcite which has taken the place of the silica is
crystalline, and probably infiltrated the moulds after the silice-
ous skeleton was dissolved and removed. When the spicules
were large or the spicular mesh not too closely interwoven, the
change has been effected without effacing the character of the
structure; but where the sponge skeleton was composed of
small and closely united spicules, not only the finer details of
the skeleton have been destroyed but in many instances the
entire internal structure is, if not obliterated, at any rate too
undefined to be satisfactorily determined. In no palaeozoic
sponge have I been able to distinguish the canals of the spi-
cules, and in but few instances their method of union, but
usually have had to rely upon a general idea of the spicules
and what the specimen preserved of the canal system.

The undoubted siliceous sponges from the Lower Silurian
strata of northern Illinois are good examples of the replace-
ment by calcite. In these the spicular mesh retains sufficient of its
original structure to give us a fair idea of its details, while the
canal systems, though often very complicated, are clearly de-
fined and readily determinate. A number of the same species
occur at Beloit, Wisconsin, but here the specimens are so poorly
preserved that nothing whatever can be made out of their in-
ternal structure. I have also obtained several closely related

214 PALEONTOLOGY OF ILLINOIS.

species from Safford's Central Limestone, in Tennessee.* There, in
common with the associated fossils, the specimens are siliceous,
but the silica has undergone so much alteration that the inter-
nal characters are no longer distinguishable. The silica in these
specimens has been much more changed than in the similarly
preserved sponges from the Astylospongia, beds of western Ten-
nessee. Here, the entire sponge consists, usually, of a flinty
mass in which the spicules and canals can often be traced out
with comparative ease.

Sponges from which the siliceous skeleton has been dissolved,
leaving perfect moulds, is another very common condition of
preservation, especially among those of the Niagara group. In
these specimens the siliceous spicular network has been entirely
removed so that, instead of the solid spicule rays and nodes,
we have only empty cavities that conform, however, most per-
fectly to the structures which formerly filled them. These moulds
generally occur in a matrix of chert or flint which is eminently
suitable for retaining the form of the sponge skeleton. In fact,
I regard this method of preservation as being more favorable
than any other met with in palaeozoic rocks since, by pressing
heated gutta-percha into the empty moulds, very perfect casts of
the spicules are obtained. By this means I have been enabled
to work out the structure of Hindia,, Aulocopium, Astylospongia,,
Palteomanon, and other genera. In several instances the arti-
ficial casts of Astylospongia, are so perfect, that they show
clearly the branching of the spicule rays. Numerous examples
are found in the Niagara strata of Tennessee, Kentucky and
Indiana, while at Spring Valley, Minnesota, in beds of the same
age, it appears that all the sponges are preserved in this condi-
tion. In the Burlington limestone of Illinois and Iowa, the
Monactinellid sponge described in this report is often preserved
in a similar manner.

The changes produced by fossilization in the structure of the
calcareous sponges is generally more serious in its effects than

* The beds from which these specimens were collected are regarded by Safford as
forming part of his Central limestone. Eecent investigations make me doubt that this
is their true position. So far as the evidence at hand permits me to judge I should say
that they constitute a distinct horizon between his Glade and Carters Creek limestones

SPONGES. 215

in the siliceous form*, though but little change may have oc-
curred in the mineral substance. As a rule the calcareous spi-
cules were minute and intimately united in the sponge fibre, so
that it required but a slight amount of alteration to obliterate
their form in the resulting fibre-crystalline mass of calcite. So
far as observed, the spicules are never recognizable in the palaeo-
zoic calcareous sponges, excepting where they are isolated or
project from the walls into the canal cavities. Some instances
have also been met with in which the calcareous skeleton has
been more or less completely replaced by silica. Several
species of Heterospongia, a new genus with affinities to Dystac-
tospongia and Strotospongia, and a general resemblance to
Jurassic species of Corynella, present examples of this condition .
These, as they occur at Cincinnati, Ohio, are always calcareous
but at several localities in central Kentucky, where most of the
fossils are also silicified, the same species are found having
their skeletons strongly charged with siliceous material. The
sponge fibre of such specimens is rough and preserves scarcely
a trace of the spicular structure though in some the course of
the canals and twisted walls can be distinguished with approxi-
mate certainty. Generally, however, this style of preservation
is anything but favorable.

GEOLOGICAL DISTRIBUTION.

As may be expected, sponges make their appearance in the
earliest fossiliferous rocks, and they are more or less numer-
ously represented in all the succeeding great divisions of the
geological scale to the present time. They attain the height of
their development in the Jurassic and Cretaceous periods, in
which rocks they form an important feature of the fauna. Their
importance is less marked in Palaeozoic and early Mesozoic
groups, though they played a less subordinate part in Palaeozoic
times than is generally supposed. The fact is, they have been
too much neglected by palaeontologists, perhaps, because the
specimens are rarely showy and in most cases appear as unsat-
isfactory, shapeless masses, little calculated to enthuse the col-
lector. But the true naturalist should see beauty in all of
Nature's handiwork, and I feel convinced, when once an interest
is aroused in the study of these obscure fossil remains, their im-

216 PALAEONTOLOGY OF ILLINOIS.

portance as factors of the palaeozoic fauna will soon manifest
itself. Thousands of specimens are now relegated to the "trash
boxes" of collectors, nearly all of whom have something among
their undetermined fossils, that would add to the list. Again, I
suspect very much, that many of the so-called "Fucoids" really
represent the remains of sponges, as has already been shown of
Dictyophyton Hall, (Hydnoceras Conrad,) Uphantsenia Van-
uxem, and Cyathophycus Walcott.

THE TACONIC SYSTEM, according to Walcott*, already repre-
sents a sponge fauna comprising six genera and thirteen species.
The figures of Leptomitus zitteli Walcott, (loc. cit.) suggest
Monactinellid affinities, or, what is perhaps more likely, they
represent basalia of some Hexactinellid sponge. The spicules of
Protospongia have all the essential characters of the Hexacti-
nellidse. The peculiar genera, Archseocyathus Billings, and
Ethmophyllum, Meek, are referred to the class with much doubt.
In certain respects they suggest a line of evolution through
Beatrices into the Stromatoporoids, wrhile other peculiarities
remind us of the Zoantharia Rugosa.

CAMBRIAN SYSTEM.! — Sponges are somewhat disproportionately
distributed in Cambrian strata, but this is in part due to the
unequal care exercised by collectors in searching for them. Thus
the Trenton and Cincinnati groups have for many years been
subjected to the most energetic searchings, and from these strata
we have a correspondingly large number of sponges. None are
as yet known from the Potsdam, but from the Calciferous group
five species are described by Billings, belonging to the genera
Calathium ?, Ethmophyllum, Rhabdaria and Trichospongia.
Billings also describes from the uncertain Quebec group, five
other species of Calathium, and the genus Trachyum, with two
species.

* C. D. Walcott, 2d Contr. to the Cambrian Faunas of N. A. Bull. U. S. Geol. Surv.,
No. 30.

t The term Cambrian as here used is equiyalent to the Lower Silurian of Mur-
chison and of the majority of American geologists; of the Ordovician of Lapworth, and
of the Cambro- Silurian of the Canadian geologists. This arrangement seems to me to be
the only just and practical settlement of the Taconic- Cambrian controversy which is re-
ceiving so much attention from geologists at present.

SPONGES. 217

The Trenton period, including the rocks between the top of
the Calciferous and the base of the Silurian, introduces a largely
increased and much better preserved sponge fauna. The HEXACTI-
XELLIDA are represented here byCyathophycus,Rauffella,Brachio-
spongia, Hyalostelia, Calathium (pars), Leptopoterion, Recepta-
cuUtes. Lepidolites and isolated spicules of a genus probably iden-
tical with Astrseospongia; the LITHISTIDA by Hindia, Astylo-
spongia(?), Anthaspidella, Zittelella, Edriospongia, Streptosolen
and Aulocopium, the last by an undescribed species from the
upper beds of the Trenton limestone in central Kentucky; and
the CALCISPONGLE, probably, by Strotospongia, Saccospongia,
Dystactospongia, Cylindroccelia and Camarocladia in the Tren-
ton limestones of Illinois and Kentucky; and byDystactospongia,
Heterospongia . Strep tosp ongia and Cylin droccelia in the Cincinnati
rocks of Ohio and Kentucky. The systematic position of Pat-
tersonia S. A. Miller, which seems identical with the lately
proposed Strobilospongia of Beecher*; and of Eosp ongia, Bil-
lings, has not yet been determined.

SILURIAN SYSTEM. — Among Silurian deposits the Niagara group
offers a number of localities where fossil sponges abound. They
are most prolific in Western Tennessee, (Perry and Decatur
counties) where the surface of the ground is sometimes thickly
strewn with good specimens of Astylospongia, Palseomanon,
Astraeospongia, and Hindia, while the genera Aulocopium,
Climacospongia, and at least one other genus, occur more
rarely. None of the strata of this system below the Niagara
have, so far as I am aware, furnished remains of sponges. It
is. however, not at all unlikely that some at any rate of the
numerous "fucoids" of the Clinton will prove eventually to be
sponges and not plants. From above the Niagara, the Lower
Helderberg contains sponges at certain localities. Hindia
sphseroidalis Duncan (Astylospongia inornata Hall) is the
principal form. This species seems to be identical with the
common Niagara form of the genus.

* Memoirs of the Peabody Museum of Yale University, vol. n, pt I, p. 14, 1889. In
this excellent contribution Mr' Beecher establishes the position of Brachiospongia. He
shows the genus to belong to the HexactineUidse and proposes a new family, Brachio-
spongidae, including, besides the type genus, also the new Strobilospongia^

—27

218 PALAEONTOLOGY OF ILLINOIS.

DEVONIAN SYSTEM.— Except in one formation, sponges are very
rare in the rocks of this age. The Hexactinellid genus Die-
tyophyton is common at several localities in the Chemung
group of New York, while Astr&ospongia is occasionally found
in the Hamilton group of Illinois and Iowa. The new genus
Syringophyllum, from Hamilton strata of Northen Michigan,
recalls the Silurian Anthaspidellidae. A few specimens, not
nearer determined, have been found among the silicified fossils
at the Falls of the Ohio. The Devonian rocks of Europe are
also very poor in sponge remains. Hinde describes Lasiocladiu,
a Monactinellid sponge from Belgium, while the Calcareous
sponges are represented, according to Zittel, by a species of
Peronella. The Lithistidae are not represented unless the cast
of a sponge from the Lower Devonian of Germany, named by
Kayser Lodanella mira, belongs here.

CARBONIFEROUS SYSTEM. — European, and more especially the
English authors, have paid considerable attention to the sponges
of this system. Carter describes from the Carboniferous lime-
stone of Scotland, the three Monactinellid genera Pulvillus,
Raphidistia and Reniera, also Holasterella. belonging to the
HEXAOTINELLIDA; and Steinman furnishes the three genera Sollacia,
Amblysiphonella and Sebargasia, which he regards as Calci-
spongise.

In American strata the MONACTINELLIDA are represented by
Belemnospongia in the Burlington limestone of Illinois, and two
species in the shales of the Keokuk group, one of which is pro-
visionally referred to Lasiocladia. The new Hystriospongia
carbonaria, from the Lower Coal Measures of Illinois, seems to
be a Tetractiuellid sponge in which the number of four-rayed
spicules is exceedingly limited, while the general character of the
skeleton of Batospongia, from the same horizon, strongly sug-
gests the CALCISPONGI^E. The HEXACTINELLIDA are represented by
species of Dictyophyton in the Waverly group of Ohio, and the
Keokuk group of Indiana and Illinois, as well as the fragments
belonging to several related genera obtained from Lower Car-
boniferous localities in Illinois and Kentucky. Uphant&nia
dawsoni is described by Whitfield from the Keokuk group of
Indiana.

SPONGES. 219

CLASSIFICATION.

While the methods of investigation demanded by the advanced
state of the study of natural science, make a natural classifica-
tion possible, they add also very largely to the labors of the
investigator. This is especially true of the student of palaeozoic
sponges, not only because the fossils of this class preserve so
little of their structural details, but also because these early
forms are ancestral types in which the characters, that in
Mesozoic and more recent times have been separately developed
into permanent structural characteristics, are as yet illy defined
and generally blended together. The commingling of subse-
quently differentiated characters, even with the best preserva-
tion, imparts a degree of uncertainty to many of our determi-
nations, but as we have in every instance sought to work out
the minute structure as fully as the state of preservation of the
fossils would admit, we hope the authorities on the subject will
not take our views too much to task when they find it neces-
sary to differ with us.

It is not deemed essential to refer to the classifications of D'Or-
bigny, Fromentel, and others, beyond stating that all have
proven utterly inadequate because of their artificial character.
This is clearly shown by the heterogeneous composition of the
groups proposed in their systems. To Prof. Zittel belongs the
honor of discovering the principle of a natural classification for
fossil sponges. He accepts as the fundamental basis of his sys-
tem the characters of the minute spicular bodies of which the
sponge skeleton is composed. The validity of the system has
already demonstrated itself by the excellent results of its appli-
cation, since, where we formerly had a chaotic intermingling of
distinct types, we now find the most harmonious arrangement.

According to the classification proposed by Prof. Zittel*, and
adopted by Dr. Hindet, and others, the Class SPONGLE is
divided into the following Orders:

* "Studien uber fossile Spongien" I. II, in, Abh. d. Bay. Akad. d. Wiss. Bd. 13. 1877-
78, and "Handbuch der Palasontologie."

t Catalogue Foss. Sponges, British Museum, 1883,

220 PALEONTOLOGY OF ILLINOIS.

1. Myxospongise Haeckel. Sponges unprovided with a solid
skeleton.

2. Ceraospongise Bronn. Skeleton consisting solely of horny
fibres.

3. Monactinellidse Zittel. Skeleton consisting entirely of uni-
axial siliceous spicules, or of horny fibres enclosing an uniaxial
siliceous core.

4. Tetractinellidss Marshall. Skeleton consisting principally
of four-rayed siliceous spicules, one usually elongated to form a
shaft. Uniaxial and stellate spicules are also present.

5. Lithistidse Schmidt. Skeleton composed of four-rayed or
irregular siliceous spicules, which are often branchy and always
closely interwoven so as to form a continuous mesh.

6. Hexactinellidse Schmidt. Skeleton composed of isolated,
or united and interwoven six-rayed siliceous spicules.

7. Calcispongiae Blainville. Skeleton composed of calcareous
spicules, either uniaxial, three or four-rayed.

Of these divisions five are known to be represented in the
palaeozoic rocks of America.

Zittel's system, as it is based mainly upon mesozoic and recent
forms, fails, like Busk's and other classifications of the Bryozoa,
to make full provisions for the palaeozoic species, and many of
them require some pressure to fit them into the accurately drawn
divisions. However until something approaching a complete
series of palaeozoic sponges can be studied, it would be worse
than useless to propose any serious changes from the arrange-
ment adopted by Prof. Zittel in his "Handbuch der Palaeontolo-
gie," excepting in such cases where the system has been improv-
ed upon by himself and other authorities on the subject.

Under this heading we desire to introduce a list of American
palaeozoic sponges, as nearly arranged according to the classi-
fication adopted as the present state of our knowledge would
admit. As several changes and innovations are proposed, some
remarks upon them are necessary to establish our claims. In
order that the list may be as available for reference as possible,
we prefer to give them here, rather than in the body of the
catalogue.

SPONGES. 221

The genera Anthaspidella, Zittelella, etc., described further on,
have certain peculiarities which forbid classing them with any
family of sponges known to me. A new family is therefore pro-
posed for their reception, and defined as follows :

ANTHASPIDELLIDJE, n. fain.

Sponges attached, simple or compound, saucer to funnel-
shaped, often turbinate, more rarely sub-cylindrical, frondescent
or sub-globose. Canal system often complicated, usually con-
sisting of two sets, crossing each other at right angles. Skele-
ton composed of four-rayed spicules, consisting of a rod-like
central portion and rapidly diverging bifurcations at each end,
the form resulting being nearly J— { shaped. The central por-
tion is placed horizontally, with the bifurcations directed parallel
with each other and at nearly right angles with the connecting
bar. The bifurcations uniting to form radial columns and the
connecting of the latter by the horizontal rods, results in form-
ing what might be called a minutely tubular skeleton.

The family above characterized is proposed for the reception
of a number of genera, mainly from Silurian strata, which in
their various characters suggest affinities with very diverse
types. Generally, the form of the sponge recalls the most typi-
cal Lithistidae.

The species of Zittelella, for instance, in their macroscopic
features resemble Jurassic Cnemidiastrum species so closely, that
the microscope is required to prove their generic distinctness.
On comparing the spicules of their internal skeletons, it becomes
evident that they do not only belong to distinct genera, but
that they really represent two very different families. On the other
hand the arrangement of the spicules in columnar series, vividly
recalls some of the Stromatoporoids. On plate VII we have
illustrated for comparison the microscopic structure of two spe-
cies of Actmostroma , Nicholson.* Recognizing the high authority
of the men who advocate placing the Stromatoporoids with
the Hydroida, it would be presumptuous on our part to deny

* In his several papers on the Stromapotoroidea, Dr. Nicholson has figured a num-
ber of species that would have served the purpose better.

222 PALEONTOLOGY OF ILLINOIS.

their conclusion, yet we may be allowed to express our views to
the effect, that the extraordinary resemblance between the co-
lumnar arrangement of the spicules in the Anthaspidellidse and
"radial pillars" of Actinostroma, etc., is due to homological
affinities rather than the result of mere accident.

With two exceptions all the genera which it is proposed to
include in the family are here described as new. Anthaspidella,
Zittelella, Streptosolen and Edriospongia are from Cambrian
strata, Aulocopium Oswald, and the very closely related Clima-
cospongia Hinde, from Silurian, and Syringophyllum from
Devonian beds. Besides these, several species now referred to
Calathium Billings belong here. That genus contains, we think,
at least two structurally distinct types. The first species des-
cribed C. formosum Billings resembles Craticularia and may be,
as has been suggested by Dr. Zittel, an early representative of
the Euretidae. C. canadense Billings or at any rate specimens
from the Trenton limestone of Tennessee which we have identi-
fied with that species, have the characteristic spicular structure
of the Anthaspidellidse. The specimens are silicified and show a
few spicules in a fairly satisfactory manner.

With the exception of Climacospongia, all the genera are
characterized by more or less well marked canal systems. Two
sets, radial and vertical, prevail in Anthaspidella, Zittelella,
Aulocopium and Edriospongia. In Streptosolen the canals in-
tertwine to such a degree, that it is difficult to separate the two
sets, while in Syringophyllum, the radial system is represented
by superficial channels only. In Climacospongia, the larger
canals are wanting, but, instead, the spicules are larger, the
horizontal bar longer, and, in consequence, the tubular mesh of
more ample construction. This genus was described by Dr.
Hinde* as a Monactinellid sponge. Specimens obtained from the
typical locality clearly demonstrate that he misinterpreted
the character of the interior skeleton, and that instead of ver-
tically and horizontally arranged simple bi-acerate spicules, they
are in reality four-rayed, and arranged in columnar series.
These are formed by the intertwining of the vertically, or rather,

*Cat. of the Poss. Sponges in the Brit. Museum, p. 18, 1883.

SPONGES. 223

radially directed end divisions of neighboring spicules. The
spaces intervening between the "columns" are traversed by the
horizontal bars imparting an irregular scalariform appearance
to the spicular network in vertical sections. In transverse sec-
tions an irregular radial arrangement is obvious. In short the
structure of the interior skeleton agrees very closely with that
of Aulocopium, and, in all essential respects, with that of the
remaining Anthaspidellids.

Figures 1 to 4 of the accompanying plate of cuts, illustrate
the structure of Climacospongia as it appears in gutta-percha
casts prepared by firmly pressing this pliable material into the
empty moulds. The casts are not perfect representations of the
original spicules, because the moulds of the "columns" are not
entirely empty; but contain patches or particles of the peroxide
of iron beside thin plates or threads of the siliceous matrix
representing minute interstices between the spicule rays, which
by their union form the columns.* Enough is shown, how-
ever, that we are not dealing with a Monactinellid sponge, but
one that is, if not a true member of the Lithistida, at any rate
very much like them.

In transverse sections the radial arrangement of the skeleton
somewhat resembles the appearance of the spicular network of
Astyloepongia and Palseomanon, but, as has been shown by
Martin and other observers, the spicules of those genera have
from six to nine rays with minutely branched terminations.
Their structure, therefore, conforms to that of the sponges in-
cluded in the Lithistid family, Anomocladina. The spicule ele-
ments of the AnthaspidellidiP, however, are very different, being
more like those which characterize the Megamorina and Tetra-
cladina and, perhaps above all, are to be considered as altogether
peculiar.

*Fig. 1 shows a feature that is likely to prove misleading. I refer to the perfora-
tions at the ends of the horizontal portion of the spicules. Similar impressions or per-
forations were noticed in sections of the Trenton genera (pi. 5, flg. 3a). The appearance
presented is sometimes rather suggestive of the "node perforations" of Becksia and
other hexactinellid genera. These perforations are, however, too irregular to be of
such a nature. Besides, the whole arrangement and character of the spicule elements
of the new family as described above would in that case have to be abandoned, a course
not to be entertained for a moment, since they are readily explained by assuming them
to represent nothing further than mere interstices left between the diverging rays of th *
spicules. That the latter are fundamentally of the four-rayed type (in the same sense as
are the skeleton elements of the Rhizomorina and Megamorina families) seems also
scarcely within the ranee of doubt.

224

PALAEONTOLOGY OF ILLINOIS.

Fig. 1.— Two columns of spicules of CZimacosponffia radiata Hinde, magnified 25 times.
Drawn from a gutta-percha cast taken from a natural mould. The specimen
is from the Niagara group of Perry county, Tenn. The finer details of struc-
ture are not preserved.

Fig. 2.— End view of several columns of same, showing their arrangement and the con-
necting bars.

Fig. 3.— Spicules of Astylospongia proemorsa Boemer, mag. 25 times, as shown in
gutta-percha casts. Niagara group, Perry county, Tenn.

Fig. 4. — Taken from another gutta-percha cast of CUmacotpongia radiata Hinde; x 25.
In this cast the structure of the columns is shown in a very satisfactory man-
ner. Position and locality same as for fig. 1.

Fig. 5.— End view of a single column of preceding; x 25.

Fig. 6.— Diagrammatic view of a spicule of Climacospongia and of the Anthaspidellidas
generally.

SPONGES. 225

Fig. 7.— Spicule of Aulocopium sp.. x55. Silurian of Gotland.

Fig. 8.— Spicule of Bhizomorine sponge (Seliscothon mantelli Goldf.. Cretaceous of Ger-
many), showing axial canal and its division at each end ; x 55. Introduced for
comparison with the Anthaspidellidae.

Fig. 9.— Small portion of surface of Hindia sphceroidalis Duncan, x 55, showing mouth
of one of the radiating canals and three spicules. Niagara group, Spring
Valley, Minn.

Fig. 10.— Portion of a gutta-percha cast taken from a vertically fractured example of
the same ; x 55.

So far as known, Aulocopium agrees in one character more
nearly with the Tetracladine and Rhizomorine sponges than do
the other genera here referred to the new family, the ends of its
spicule rays, namely, being branched. In that respect, as well
as in being considerably smaller, the spicules of Aulocopium
differ from those of Climacospongia, the rays in the latter being,
apparently always, simple and smooth. In none of the Trenton
genera could the construction of the columns be determined, all
the finer details having been destroyed during the process of
calcification.

As regards the systematic position of the proposed family
every character strongly favors a reference to the Lithistida?.
But when it comes to saying to which of the four already
established families of the order the new division is the near-
est related, we cannot speak with the same confidence. In
the first place the comparatively regular form and grouping
of the spicules suggests the Tetracladina, but the fact that
these bodies are built upon a totally different plan, at once
negatives the idea that any very intimate relationship exists
here. In the Tetracladina the four arms of the spicules diverge
from a center at angles of 120°. In the Anthaspidellidae, on
the other hand, the four rays are thrown off in pairs from the
ends of what might be called a profoundly elongated node
(the horizontal central bar).

The swollen central node and the general irregularity of the
skeleton elements distinguish the Anomocladina.

-28

226 PALEONTOLOGY OF ILLINOIS.

In the Rhizomorina the branchy or nodulose and irregularly
divided character of the spicules imparts a very distinctive ap-
pearance to them, yet when closely examined they are often
found to be comparable with those of the Anthaspidellidae.
Thus, in Jerieca, Zittel, a central rod and two principal divi-
sions at each end are frequently determinable. Lastly, in the
Megamorina, the large spicules from which the family takes
its name, occasionally also present points for comparison.

In the canal system and outer form of the spongarium the
Anthaspidellidae agree best with the Rhizomorine sponges. Since
the skeleton elements also appear to resemble those of that
family more than they do those of the Tetracladina, Megamo-
rina and Anomocladina, it seems advisable to regard the new
family as the initial one of the Lithistidae, and as the best re-
presented section of the order in the palaeozoic rocks.

HINDIA Duncan.

Microspongia Miller and Dyer, Jour. Cin. Soc. Nat. Hist. vol. I. p. 37, 1878.

The genus Hindia was originally described in 1879, by Duncan
as a calcareous sponge.* This view of the nature of the sponge
was in my estimation successfully combated by both Hindet
and Rauff$. These two observers, however, differ in the position
assigned by them to the genus, the former being inclined to re-
gard the genus as belonging to the Lithistid family Anomalo-
cladina, while the latter refers it without question to the Te-
tracladina. My own investigations lead me to accept Dr. Rauff's
conclusions as the most probable. In the main, my conclusions
respecting the minute structure of the sponge agree very closely
with those of both Rauff and Hinde, causing a detailed discus-
sion of the genus to be almost superfluous. Still, as the
points on which we differ will be brought out to better advan-
tage, and, particularly since no account of this important fossil

* Ann. and Mag. Nat. Hist., ser. 5, vol. 4, p. 84.

\ Catal. Foss. Sponges, Brit. Mus., p. 57, 1883; and Ann. Mag. Nat. Hist, for Jan. 1887.

J "Ueber die Gattung Hindia Duncan;" Sitzungsb. der Niederrh. Gesell. zu Bonn;
Bitzung vom 10 Mar. 1886.

SPONGES. 227

sponge havS yet appeared in any American publication, I need
not apologize for the following brief statement of facts relating
to the genus and the several species known to me.

The type of Hindia is the H. sphseroidalin described by Duncan
from Lower Helderberg specimens collected by Dr. G. J. Hinde,
in New Brunswick. The same were previously described by Dr.
Hinde as a tabulate coral and named SphaeroHtes nicbolsoni.
Of this paper nothing further than an abstract has ever been
published!. The same species had been described and figured
fifteen years before by Roemer from the Niagara of western Ten-
nessee, and identified by him with Goldfuss' Calamopora fibrosa*.
Again, it appears that Hall's description of his Astylospongia
inornata (16th Reg't Rep't, 1863) is founded upon specimens of
the same species from Lower Helderberg localities in New York.

We have here then a fossil which has received no less than
four distinct specific names, and it is really a very difficult mat-
ter to decide which of them should be retained. Hinde and
Rauff use fibrosa, but as Roemer clearly regarded the Tennessee
specimens as specifically identical with Golfuss' Calamopora
fibrosa, I cannot see why he should be credited with a name of
which he is not the author.

That he gave a sufficiently clear description of the Tennessee
specimens cannot be denied, but that point has no bearing
upon the real question, and it is of no consequence in the issue
whether we decide his figures and description to be inadequate,
or complete and sufficient for the identification of the species.
The course almost universally adopted in cases of this kind (to
my mind also the only rational and just one) is to give a new
name to the species which upon subsequent investigation proves
to have been erroneously identified with another. When they
belong to the same genus the giving of a new name is, of course im-
perative. Why should the proceedings be any different when it
happens, as in this case, that two species so confounded belong
to different genera?

t Abstract of the Proc. Geol, Soc., No. 3«.i5, 1875.

* F. Roemer, "Silur. Fauna des WestL Tenn. p. 20, pi. 2, fig. 2, 1860.

228 PALAEONTOLOGY OF ILLINOIS.

Hall's name inornata has a better claim to be retained, since
not only did its author recognize the fossil as a sponge, but he
also proposed a new name for it. The only objection to the
adoption of Hall's name is that his description (no figures
accompanying it) is not sufficient for the recognition of the
species. The form is described well enough by the terms "globose
or subglobose," but the statement that "from the point which
appears to be the base, there are, in well preserved specimens.
a few indistinct radiating lines," is misleading. Of the interior
Hall says only that "a transverse section exhibits the charac-
teristics of other species of the genus" (L e. Astylospongia); now
this statement not only does not aid in distinguishing the spe-
cies, but is opposed to the facts, since the Helderberg specimens
really belong to Hindia, and the interiors of that genus and of
Astylospongia are in no respect alike.

Hinde's name, Sphserolites nicholsoni, would have been accept-
able and appropriate enough had it been established, but as-
nothing more than only a short abstract of his paper on the
fossil was published, neither the specific nor generic name is
available.

Up to this time only Duncan's work on the species fulfilled all
the requirements of proper publication, and, as he was the first
to recognize the essential characters of the fossil, and to give
us an adequate diagnosis of it, his name Hindia sphseroidalis
is justly entitled to be retained for the species.

From the above we see that the species under consideration
was first referred to Calamopora, then to Astylospongia, and
subsequently formed the foundation of two new genera.
Of the latter, Sphaerolites, as has already been stated, has no
claim to recognition, the author of the name having failed to
publish his paper, and thus failed to establish his genus.

There is, however, another generic name that may dispute the
title with Hindia. I refer to Microspongia, a genus proposed in
1878 by Miller and Dyer. Their description on page 37, vol. I,
Jour. Cin. Soc. Nat. Hist., reads as follows:

"A free calcareous sponge, destitute of an epitheca. The tex-
ture is finely porous, without large canals or openings on the
surface. Spicules (?) very minute and needle-shaped."

SPONGES. 229

This description would scarcely lead anyone to suspect that
the genus was founded upon a species which there is reason to
believe, is congeneric with Hindia sphaeroidalis. This belief is
based upon the fact that only one globular sponge is known to
me from the Cincinnati group, and that is unquestionably a
Hindia. I have also seen specimens of this species which had
been identified by Mr. Miller with his Microspongia gregaria.

If the originals of Microspongia are indeed the same as Hindia
then we must decide whether the former name, which was pro-
posed a year or more before the latter, is or is not entitled to
recognition. If it is essential that a species or genus to be es-
tablished must be described so that it can be recognized, then
Microspongia cannot stand. There is nothing in the above
quoted description, save the assertions that it is a calcareous
sponge with (?) very minute needle shaped spicules, which would
not apply equally well to Astylospongia, Aulocopium and one
or two other palaeozoic subspherical free sponges; and, taking
for granted that the two names are really founded upon con-
generic species, the description is false in the very points ex-
cepted, since Hindia is an undoubted siliceous Lithistid sponge
with spicules of the Tetracladine type. Besides, the most im-
portant distinguishing features are not mentioned at all. Thus,
while there are many reasons for abandoning the name Micro-
spongia (always granting, of course, that the two names relate
to one and the same genus) I see none of sufficient importance
to justify its adoption at the expense of Hindia.

Hindia is represented in Cambrian and Silurian strata by at
least three distinguishable varieties or species. The earliest, so
far as known, is from near the base of the Trenton group
(?Birdseye limestone) of northern Illinois. This is described in
this volume by Dr. Everett and the author as Hindia insequalis
its main distinctive character being an unusual inequality in
the size of the radial tubes. A nearly related smaller species
(H. parva Ulrich) occurs at numerous localities in the upper
or Galena division of the Trenton limestone, while a supposed
variety of the same is occasionally found in the upper beds of
the Cincinnati group at several localities in Illinois and Ohio.
The third species is the H. sphteroidalis. This species, which

230 PALEONTOLOGY OF ILLINOIS.

must be regarded as the type of the genus, has a wide geograph-
ical distribution, and is common at many localities. It is known
from the Silurian of Russia, Gotland, Germany, New Brunswick,
New York, Indiana, Kentucky, western Tennessee and Minne-
sota. Of the specimens from American localities, those coming
from the western states are in most cases silicified. In a large
proportion of these again the skeleton has been more or less
completely dissolved away, leaving only the empty moulds. In
all of these, however, the superficial layers of spicules are pre-
served, but it is only in rare instances that the spicules were
not distorted during the changes in mineral composition which
nearly all fossil sponges have undergone during the process of
fossilization.

In the calcareous examples of the genus, like those from the
Cincinnati and Lower Helderberg groups, and part of those
from Trenton and Niagara deposits, the minute details of struc-
ture are not clearly recognizable, but they serve very well in
giving an idea of the general plan of construction. They show,
for instance, that the skeleton is tubular and that the tubes,
which in the same species (H. intequalis) may vary in diameter
from 0.2 to 0.7 mm., radiate in all directions from a central
point. These tubes or canals enlarge very slightly toward the
outer surface, and new canals are continually interpolated. In
cross section they are obscurely hexagonal or subcircular, with
their walls thin and perforated by six rows of minute round
pores. Occasionally, also, sections of these calcareous examples
may afford obscure evidences of the individual spicules, but they
are never so conclusive as in the siliceous specimens and natural
moulds.

The most perfect moulds seen by me come from the Niagara
beds at Spring Valley in southern Minnesota. From these I
have prepared a number of gutta-percha casts that for sharp-
ness and beauty leave little to wish for.

Fig. 10, of the plate of cuts on page 224, represents an accu-
rate camera lucida drawing of a small portion of one of these
casts magnified 55 diameters. The specimen from which this
cast was prepared is fractured vertically through the center and
consequently exhibits the appearance of the skeleton on the
inner side of the broken tubes. To understand this illustration
it is necessary to study it in conjunction with fig. 9, which

SPONGES. 231

represents a small portion of the actual skeleton as it appears
at the surface of one of the specimens from the same locality.

These figures, I believe, show in a reasonably clear manner
that we are dealing with a Lithistid sponge of the Tetracladina
type. The spicules are distinctly four-rayed, though the fourth
ray is much less developed than the others and rarely is more
than a mere stump.

In the typical Tetracladina the rays of the spicules diverge
from a center at angles of about 120°. In Hindiathe rays are
similarly disposed, but the regular arrangement of the spicules
into superimposed radial series so as to form tubes, appears
not yet to have been noticed in any other genus of the family.
It is a feature in which the genus may be said to simulate the
Anthaspidellidae.

The individual spicules have, as has been stated, four rays or
arms extending from an inflated center. Three of the rays are
nearly straight, of nearly equal length, with their extremities
expanded mostly in a vertical direction. By their union a tripod-
shaped body is formed from the upper surface of which the short
fourth ray projects.

The connected structure of the skeleton is easily understood
after we have once determined the true form of the individual
spicules. In the first place the spicules form rather regular con-
centric layers, in which the individuals are arranged alternately
so that any portion of each spicule is placed directly over or
beneath the corresponding portion of the spicules of the third,
fifth, seventh and ninth layers. The stumpy fourth ray is
always directed toward the exterior, while the three tripodal
rays extend toward the central nodes of three adjacent spicules
of the layer immediately beneath. The upper portions of the
expanded terminations in each case clasps about one-third of
the fourth ray of the latter, while the lower portion extends
downward in a recurving manner to the node or fourth ray of
the spicule directly beneath itf. This process is carried on inde-
finitely, so that while each spicule is connected by three rays

+ According to Dr. Bauff, the terminations are toothed and the junction of the spicules
effected by the interlocking of the dentate portions. Although my material does not
permit me to corroborate his observations on this point, I am not by any means ready
to assert that he has misinterpreted the appearance of his specimens.

232 PALEONTOLOGY OF ILLINOIS.

with three spicules of the layer next below it, it in like manner
supports, on the upper side of its node and arms three rays of
different spicules belonging to the series or layer next above.

The Minnesota specimens, which are in a better state of preser-
vation than any others seen by me, exhibit at the surface great
numbers of exceedingly minute, apparently acerate spicules,
besides a small number of large Hexactinellids that are treated
of in the next paragraph. The minute forms may represent a
dermal layer, or so-called "flesh spicules;" or they may belong
to an altogether different sponge, in which case their associa-
tion with Hindia sphseroidalis would be purely accidental.

On plate II, fig. 4c represents a magnified view of a large
Hexactinellid spicule, which is generally found with Hindia
sphaeroidalis, and not infrequently adheres to the surface of that
sponge. At one time I supposed, because of their association,
that they might belong to the surface layer of that species, but
since the totally different character of the spicules of Hindia
was ascertained, I have concluded that I was in error, and that
the isolated spicules belong to a very different sponge. They
resemble the regular six-rayed spicules of Hyalostelia, but as
yet, I have not found with them any of the rod-like, stellate,
nor anchor shaped spicules, which likewise occur (with the
simple Hexactinellid forms) in H. smithi Y. & Y., the type of
the genus. Provisionally, the spicules may be named Hyalostelia
solivaga. In searching a slab of Lower Silurian limestone from
near Cape Girardeau, Mo., for Bryozoa, I found smaller, but
otherwise very similar spicules. Such spicules are also occasion-
ally found associated with H. parva Ulrich, in the upper beds
of the Trenton in Kentucky.

SPONGES.

233

TABULAR LIST AND CLASSIFICATION OF
AMERICAN PALEOZOIC SPONGES.

The arrangement in families and orders is provisional, as
future investigations will no doubt necessitate changes. Species
marked with an asterisk to the left, are described or discussed
in this volume.

~ —

Class SPONGL^.

Order MONACTINELLIDA Zittel.
LEPTOMITUS Walcott, 1886

L. zitteli Walcott. (This genus is perhaps
founded upon the basalia of some Hexac-
tinellid sponge)

BELEMXOSPONGIA Ulrich, 1889.
*B. fascicularis Ulrich...

LASIOCLADIA Hinde, 1884.
'L. hindei Ulrich...

Order TETRACTINELLIDA Marshall.

HYSTRIOSPONGIA Ulrich, 1880

hH. carbonaria Ulrich

—29

2.34

PALEONTOLOGY OF ILLINOIS.

Order LITHISTIDA O. Schmidt.

Family ANOMOCLADINA Zittel.
ASTYLOSPONGIA Roomer, 1860

A. Christiana Meek and Worthen

A. imbricato-articulata Eoemer

A. inciso-lobata Eoemer

A.? parvula Billings

A.? perryi Billings

*A. praemorsa Goldfuss

A. praeraorsa var. nux-moschata Hall.

A. roemeri Hinde

A. stellatim-sulcata Eoemer...

PALJSOMANON Eoemer, 1860

P. cratera Eoemer

P. bursa Hall. ..

EOSPONGIA Billings, 1861.

E. roemeri Billings

E. varians Billings...

CYATHOSPONGIA Hall, 188-\
C. excrescens Hall...

Family TETRACLADINA Zittel.
HINDIA Duncan, 1879

*H. inaequalis Ulrich and Everett.

*H. parva Ulrich

*H. sphseroidalis Duncan

Family ANTHASPIDELLID.E Ulrich.
ANTHASPIDELLA U. & E., 1889

*A. florifera. U. .(; E

*A. firma U. & E

*A. fenestrata U. & E.

*A. grandis U. & E

SPONGES.

235

-'£•

*A.? magnifica U. & E

*A. marnillata U. & E.....
*A. parvistellata U. & E.

*A. obliqua U. & E

*A. scutula U. & E...

ZlTTELELLA U. & E., 1889.

*Z. inosculata U. & E

*Z. lobata U. & E

*Z. trentonensis Wort hen, sp

*Z. typicalis *7. <£ JE

*Z. typicalis var. pistilliformis U. & E.
*Z. typicalis Far. subrotunda Z7. & E ..
*Z. typicalis var. turbinata U. & E

EDRIOSPONGIA U. & E., 1889.
'E. basalis U. & E...

STREPTOSOLEN U. & E., 1889.
*S. obconicus U. & E...

SYRINGOPHYLLUM Ulricb, 1889.
S. wort herd Ulrich..

CLIMACOSPONGIA Hinde, 1883
* C. radialis Hinde...

CALATHIOI Billings, 18651.

C. affine Billings

C. anstedi Billings

C. ?canadense Billings

C. fittoni Billings

C. formosum Billings

C. pannosum Billings

C. paradoxicum Billings

*C. ??infelix U. & E ..

t Only the doubtful species of this genus belong to this family. The typical species
probably belong with the Hexactinellida.

236

PALAEONTOLOGY OF ILLINOIS.

Order HEXACTINELLIDA O. Schmidt.
Suborder LYSSACINA Zittel.

Family DICTYOSPONGID.E HalR.

CLEODIGTYA Hall, 1884

C. gloriosa Hall

C. ?mohri Hall...

RATJFFELLA Ulrich, 1889.

R. filosa Ulrich

B. palmipes Ulrich

CYATHOPHYCUS Walcott, 1879

C. reticulatum Walcott

C. subsphericum Walcott

C. quebecense Dawson

DICTYOPHYTON Hall, 1863.

•>*

abacus Hall

annulatum Hall...

baculum Hall

cinctum Hall

conradi Hall

D. cylindricum Whit field.

D. fenestratum Hall

D. filitextile Hall

D. hamiltonense Hall

D. irregulare Hall

D. nodosum Hall

parallelum Hall

patulum Hall ,

prism aticurn Hall

D.
I).
D.

D. ? redfieldi Hall.

: In the 35th Regt. Eept., Prof. Hall defines the family and a number of genera which
he proposes to place in it. At this time I am not prepared to offer an opinion as to the
validity of the proposed genera, nor of the numerous species which accompany them.

237

D. rude Hall

D. sacculns Hall

D. telumHall

D. tenue Hall

D. tuberosum Conrad

ECTEXODICTYA Hall, 1884.

K. burlingtonensis Hall

E. eccentrica Hall

E. expansa Hall

E. implexa Hall

LYRODICTYA Hall, 1884

L. romingeri Hall

PHEAGMODICTYA Hall, 1884

P. catilliformis Whit field.

P. lineata Hall

P. patelliformis Hall

PHYSOSPONGIA Hall, 1884.

P. alternata Hall

P. colletti Hall

P. dawsoni \Vhitfield sp.

THAMNODICTYA Hall, 1884

T. newberryi Hall

UPHANT.ENIA Vanuxem, 1843.
U. chemungensis Vanuxem

Protospongia Salter, 1864

P. fenestrata Salter

P. ? minor Matthew

P. ? minor var. distans Matthew
P, tetraneina Dawson

238

PALEONTOLOGY OF ILLINOIS.

FAMILY MONAKID^ Marshall
ASTILEOSPONGIA Roemer, 1860,

A. hamiltonensis Meek and Worthen.
A. meniscus Roemer...

FAMILY POLLAKIDvE Marshall

HYALOSTELIA Zittel, 1878.

* H. delicatula Ulrich...
H. metissica Dawson.

* H. solivaga Ulrich

•>*

ASTROCONIA Sollas, 1881.
A. grant! Sollas

FAMILY BRACHIOSPONGID^E Beecher.

BRACHIOSPONGIA Marsh, 1867.
A. digitata Owen, sp

FAMILY RECEPTACULITID^ Hinde.
RECEPTACULITES DeFrance...

Mr. S. A. Miller gives a list of 24 species of
this genus in his "American Palaeozoic Fossils"
(edition of 1883). How many of these will
prove to be valid species, and what forms, if
any, are referable to Ischadites Murchison,
and Acanthoconia Hinde, I am unable to say.
I am, however, aware that Dr. Hinde has re-
viewed nearly all the American species in his
valuable memoir on the Receptaculitidse, but
as this work is, unfortunately, not within
my reach at present, I must be content with
simply referring the reader to it.

SPOX(;I:S.

239

Taconic

Cambrian . . .

Silurian

Devonian —

II

= -.

_ —

• 5

• o-

• o

. p

0

o

K
a>
P

1C

LEPIDOLITES Ulrich. 1879

*

L. dickhauti Ulrich

*

L. elongatus Ulrich :

*

LEPTOPOTERION Ulrich, 1889

*

L. mammiferum Ulrich

*

Order CALCISPONGI^ Blaineville.
Family PHARETROXES ZitteL
BATOSPONGIA Ulrich, 1889

*

* B spicata Ulrich

*

CAMAROCLADIA U. & E., 1889

*

* C dichotoma, U & E

*

DYST \CTOSPO\GI\ S A. Miller, 1882

*

* D insolens S A Miller

*

D minima Ulrich

*

* D minor U & E.

*

* D rudis U. & E

«

HETEROSPOXGI v Ulrich, 1889

*

H subram osa Ulrich

*

H knolti Ulrir-h

*

H aspera Ulrich

*

S^CCOSPOXGII Ulrich, 1889

*

S rudis Ulrich

*

S danvillpnsis Ulrich

*

STROTOSPOXGIA U & E 1889

*

* S. maculosa U. <£- E...

*

240

PALEONTOLOGY OF ILLINOIS.

STREPTOSPONGIA Ulrich, 1889.
S. labjrinthica Ulrich

CYLINDROCCELIA Ulrich, 1889.

C. endpceroidea Ulrich....

C. covingtonensis Ulrich.

C. minnesotensis Ulrich..

C. minor Ulrich...

INCERT/E SEDIS.
ARCH.EOCYATHUS Billings, 1862

A. atlanticus Billings

A. billingsi Walcott

A? pavonoides Matthew

AULOCOPINA Billings, 1875.
A. granti Billings

EOCORYNE Matthew.
E. gemina Matthew

ETHMOPHYLLUM Meek, 1868.

E. minganense Billings, sp

E. profundum Billings, sp

E. rarum Ford, sp

E. rensselaericum Ford, sp

E. whitneyi Meek

PATTERSONIA S. A. Miller, 1882.
P. difficilis S. A. Miller...

RHABDARIA Billings, 1865.

R. fragilis Billings..
R. furcata Billings.

SPONGES.

241

Ta«onio...

Cambrian

Silurian...

Devonian.

—00

H

- •

.M

• cr
• o

Q

;
g_

2

•

. D

:

RIBEIRIA Sharpe, 1853

*

R .? calcifera Billings

*

R.? longiuscula Billings

*

TRACHYUM Billings, 1865

*

T. cyathif orme Billings

*

T. rugosum Billings

*

TRICHOSPONGIA Billings, 1865

*

T. sericea Billings

*

-30

PART II.

PALEONTOLOGY OF ILLINOIS,

SECTION IV.

SPONGES OF THE DEVONIAN AND CABBONIFEROUS SYSTEMS.
BY E. 0. ULRICH.

SPONGES. 245

SPONGES OF THE DEVONIAN AND CARBON-
IFEROUS SYSTEMS.

HYSTRIOSPONGIA CARBONARIA n. gen. et sp.

PL VI, Fte. 3.

The specimens which \ve propose to designate as above, are
associated with species of the bryozoan genera Fenestella, Poly-
pora and Prismopora, on a small slab of bituminous limestone.
Their original form seems to have been sub-globular or ovoid,
and less than 12 mm. in diameter, with the spicules arranged
in a radiate manner from the base, sometimes parallel but at
other times more irregular than those figured. The bulk of the
sponge skeleton is composed of small Macerate spicules, about
1 m.m. in length, and 0.03 mm. in thickness. They are straight
and taper each way to the pointed ends. Among them may be
noticed a small number of similar spicules having one end trifid.
A few four-rayed spicules of larger dimensions were also ob-
served. In these the shaft is about 2 mm. long and 0.07 mm.
thick, while the head rays are short and form the outline of an
inverted three-sided pyramid. Acerate spicules 2 or 3 mm. long
also occur among the smaller ones.

This sponge, as defined above, differs from Tetbyopsis Zittel,
and more especially from Pachastrella Schmidt, in the very
limited number of the trifid spicules, and the small size of the
acerate spicules. In Ophiorbapbidites Carter, the four-rayed
spicules are also few, but the uniaxial forms are much longer
and wavy.

246

PALEONTOLOGY OF ILLINOIS.

In the residue left after freeing one of the specimens from the
matrix by means of acid, I found, beside the spicules above de-
scribed, a number of others, which could scarcely have belonged
to this sponge. Some belong to the genus Batospongia, founded
upon specimens from the same locality and supposed to be a
calcareous sponge.

Another kind, represented in
the accompanying wood-cut,
is of regular Hexactinellid
form, and probably belonged
to a delicate sponge of the
(type of Hyalostelia Zittel.
This supposition is strength-
ened by the fact that they
are associated with numerous
fragments of linear spicules or

Fig. 1. A triflcl spicule of Hysti iospongia car- rods, fl'Om 0.07 to 0.12 Him.

bonaria,*x 25.
Fig. 2. Small six-rayed spicule of Hyalostelia thick. The longest fragment

delicatula, x 25.

Fig. 3. one of medium size, x25. observed has a length of 5 mm.

These spicules, being more slender and in all respects more
delicate than those of the several species of that genus known,
I propose to designate, provisionally, with the name Hyalo-
stelia delicatula.

Position and locality: Near the base of the coal measures at
Seville, 111.

BATOSPONGIA SPICATA n. gen. et sp.

PL VI. Figs. 2-2a,2b.

Sponge sub-hemispherical or sub-globose, consisting of small
in osculating sub-cylindrical or flattened branches, 0.5 mm. to 1.5
mm. in diameter, which arise from a reticulated basal portion,
and give the sponge a brushy appearance. In the perfect state
the base is covered with a dense dermal layer, which, when
separated, exhibits on its inner side a network of substellate or
irregularly branched spicule fibre. The meshes of the reticulated
basal portion of the sponge, (PI. VI, fig. 2,) vary in size from

SPONGES. 247

0.5 mm, to nearly 2, mm., and are arranged in an obscurely
radiate manner. The branches are composed of small irregularly
branched spicules (fibre?) which are compactly interwoven in
the central region of the branches, but more loosely near the
surface, where their form is approximately determinable. The
branchlets of the spicules are slender and pointed, and project
in all directions, so that the branches, when magnified, have a
very spiny appearance. Extremely minute a/cerate spicules,
scarcely 0.5 m.m. long, occur between the branched spicules, and
in the matrix filling the space between the sponge branches.

So far as they can be made out the spicules of this species,
agree, in a general way, with those belonging to the Lithistid
family Rhizomorina. On the other hand the magnified branches
are not unlike the spiny fibres of some of the Calcispongiae
(e. g. Peronella). and I do not consider it at all improbable,
that better preserved examples will show that, instead of irregu-
lar four-rayed spicules with bifurcated rays, the spicules are
really three-rayed. Their association with numerous minute
acerate spicules, is more indicative of the Calcispongiae than the
Lithistida. Another circumstance suggesting an originally cal-
careous skeleton, was observed in freeing fragments of the sponge
from the rock by treating with acid. One specimen proved to
be siliceous, a fragment of another was so only in part, while
the third (the specimen represented by fig. 2) proved, unfortu-
nately, to be entirely calcareous, as it was nearly destroyed
before its character was noticed. The residue of a part of the
last specimen contained, beside numerous spicules of Hystrio-
spongia, also several small partially silicified fragments of
bryozoa.

None of the Calcareous or Lithistid genera of sponges with
which I am acquainted, sufficiently resemble Batospongia to
necessitate detailed comparisons.

Position and locality: The specimens are contained in a slab
of bituminous limestone obtained from a layer near the base of
the Coal measures, at Seville, 111., where they are associated with
Hystriospongia carbonaria, Hyalostelia delicatula, and numer-
ous brvozoa.

248 PALEONTOLOGY OF ILLINOIS.

BELEMNOSPONGIA nov. gen.

Sponges free (?), composed of elongate acerate spicules, which
radiate upward and outward from a pointed base. The spicules
are large, sub-equal and joined to each other by short processes,
while they tend to arrange themselves into fascicles.

I am not acquainted with any genus of this order of the
sponges from which Belemnospongia is not distinguished by the
large size of the spicules, coupled with their tendency to become
fasciculate, and in being united to each other by short lateral
processes.

In a letter to the author, Dr. Hinde suggests that this genus
might be compared with his Climacospongia. During the past
summer (1886), I made extensive collections of the sponges
from the Niagara group of Tennessee, and among them I found
no difficulty in detecting several specimens of C. radiata. Upon
careful examination I find that instead of belonging to the
Monactinellida, as asserted by Dr. Hinde, Climacospongia is a
real Lithistid, comparing favorably in the arrangement of the
spicular mesh with the Anthaspidellidre, to which family I pro-
pose to refer the genus.

BELEMNOSPONGIA FASCICULARIS n. sp.

PL III, fig. 2, 2a, 2b.

Sponges consisting of rather large acerate spicules, that radi-
ate upward and outward to form a loose sub-hemispheric or
discoid mass, with the base pointed, and the centre of the upper
surface depressed. The spicules are straight, cylindrical, taper-
ing gently to both extremities, 4 mm. to 8 mm. in length, 0.18
mm. in diameter, and united to each other by a small number
of lateral processes, exhibiting at the same time, a more or less
marked tendency to arrange themselves into bundles of three
or more. At the surface of the best example the spicules are
as a rule, smaller than those in the inner portions of the skele-
ton.

The specimens are preserved in chert nodules, and in all, save
the one figured, the spicules have been dissolved and removed,
leaving only the empty moulds. As is shown by a fracture,

SPONGES. 249

they are likewise gone in the interior of the mass of the illustrated
example (PI. Ill, fig. 2a). At the surface, however, the spicules
themselves are preserved.

Position and locality: Rare in the cherty layers of the Bur-
lington limestone, at Burlington, Iowa, and Montezuma, Pike
county, Illinois.

From the shales of the Keokuk group I have collected speci-
mens of two additional Monactinellid or possible Hexactinellid
sponges, which, however, are generic-ally distinct from Belemno-
spongia faxcicularis. One is composed of extremely fine parallel
fibres, or spicules, the length of which could not be determined.
The other, as it is not uncommon, and easily recognized, I pro-
pose to name Lasiocladia hindei. A brief description is as
follows :

LASIOCLADIA HINDEI, n. sp.

Sponge skeleton composed of elongate, slender, straight,
acerate spicules, pointed at both ends, and closely arranged
in sub-parallel series; their size is generally quite uniform, and
varies little from 6 or 7 mm. in length, by 0.12 mm. in diameter.

The broken spicules of this species, are frequently seen scat-
tered over the surface of slabs between the fronds of Fenestella
and other bryozoa. A small slab, about two and one-half inches
square and more than one-half inch thick, from Nauvoo, Illi-
nois, is almost entirely composed of them. In this condition
they present no recognizable arrangement, and only one speci-
men has been observed in which their normal arrangement is
preserved. This is a very thin elongate fragment about 35
mm. long, by 7 or 8 mm. in width, which, under the ordinary
pocket lens, presents the appearance of being composed of long-
itudinal fibr

The type of the genus (L. compmssa Hiude, from the Lower
Devonian of Belgium) differs from L. hindei, in having stouter
and shorter spicules. They are also differently arranged, in
being directed upward and outward, instead of in longitudinal
series.

—31

250 PALEONTOLOGY OF ILLINOIS.

Position and locality: In the shales of the Keoknk group at
Nauvoo, Illinois; Keokuk, Iowa; and Kings Mt. tunnel, on the
C. S. R, E., Lincoln county, Kentucky.

SYRINGOPHYLLUM nov. gen.

Sponges frondescent, with both sides deeply channeled. Chan-
nels parallel, increasing in number by interpolation. Vertical
canals, arranged in linear series, pass through the expansion
from side to side, opening into the bottom of the channels. In-
terspaces minutely tubular, the small canals originating in the
central region of the expansion, and proceeding to each surface in
a curved direction. Spicules and minute characters of skeleton
apparently indistinguishable from Antlinxjiidclla.

This genus, though clearly a member of the Anthaspidellidse,
differs greatly from the typical genera of the family, in the form
of the sponge, arrangement of the canals, and the absence of
distinct oscula.

Several sponges now referred to Calathiuni (e. g. C. canadense
Billings and C. infelix U. & E.) are, perhaps, the nearest rela-
tives known. From these Syringophyllum is distinguished by
the frondescent form of the sponge.

SYBINGOPHYLLVM WOBTHENI n. sp.

PI. VII, figs. 4, 4a, 4b, 4c, 4d, 4e.

Sponge frondescent, consisting of an expansion several inches
in diameter and 5 mm. thick. Both sides are deeply channeled
in a like manner. The channels are parallel, radiately arranged
from the base, five or six in 10 mm., increasing in number by
interpolation.

The mouths of vertical canals, passing through the frond from
side to side, are arranged in linear series, five to seven in 10 mm.,
along the bottom of the channels. The ridges between the rows
of canals which, when worn, appear to be striated, are com-
posed of a finely tubular spicular mesh, the spicules being-
arranged so as to form columnar series, extending from the

SPONGES. 251

centre of the expansion in a gently curved direction to each
.surface. In sections the spicular mesh is somewhat irregular,
but the true Anthaspidellid type is often observable. (PI. VII,
fig. 4b.) The spicules in the spaces between the vertical canals
an- smaller and much more irregular, than those in the radiat-
inir ridges.

The specific name is given in honor of our distinguished chief,
Prof. A. H. Worthen, who collected the unique example figured.

Position find locality: In shales of the Hamilton group, asso-
ciated with numerous corals and bryozoa, at Thunder Bay
Island, Michigan.

PART II.

PALAEONTOLOGY OF ILLINOIS.

SECTION V.

DESCRIPTIONS OF LOWER SILURIAN SPONGES,
BY E. 0. ULRICH AND OLIVER EVERETT.

SPONGES. 255

DESCRIPTIONS OF LOWER SILURIAN SPONGES.

The collection described on the following pages, comprises,
without doubt, the most interesting and important addition to
our knowledge of Palaeozoic sponges ever made. The collection
is so varied, and the preservation of the numerous specimens
in ii^neral so favorable, that we have been able to make out
witli reasonable certainty, representatives of no less than three
orders and ten genera. The Lithistida include by far the great-
est number of the species, and the genera Hindis, Antbaspidella,
Zittrfella, Edriospongia, and Streptospongia, as well as a section
of Calathium. The minute structure of these genera, though
mostly of a type not well recognized before, always contains
the essential characters of the order. The remaining genera
Strotospongia. Dyataetospongia and Camerocladia, apparently
belong to the Calcispongiae.

All the specimens were collected by Dr. Everett at a quarry
situated three miles northwest of his home in Dixon, 111. They
a iv found only in a shaly layer of Trenton limestone, from
one to four or five inches thick, lying between heavy layers of
sub-crystalline limestone, about twenty-five feet above the top
of the St. Peter's sandstone. It is called the mud layer by the
quarry men, but on examination it is found to be largely made
up of organic remains. The shale is crowded with the stems of
Pal&ophj-cus and Biithotrephis, while the enclosed thin slabs of
limestone contain many of the characteristic fossils of the
Trenton group. The sponges may be scattered all through the
layer, or confined to particular spots in which they are es-
pecially abundant. Some of the slabs from these favored spots
are literally covered with fragmentary and complete specimens.

25G PALAEONTOLOGY OF ILLINOIS.

The following list of characteristic Lower Trenton fossils have
been recognized in the sponge layer:
Buthotrephis succulens Hall.
Palaeophycus simplex Hall.
Monotrypa undulata Nicholson.
Homotrypa arbuscula Ulrich.
Poteriocrinus gracilis Hall.
Strophomena camerata Conrad.
Strophomena deltoidea Conrad.
Streptorhynchus filitextus Hall.
Orthis bellarugosa Count d.
Orthis pervetus Conrad.

O. (Platystrophia) lynx Eichwald (small var.)-
Raphistoma lenticulare Emmons.
Pleurotomaria rotuloides Hull.
Pleurotomaria subconica Hall.
Fusispira vittata Hall.
Fusispira subfnsiformis? Hall.
Subulites elongatus Conrad.
Murchisonia gracilis Hall.
Maclurea bigsbyi Hall.
Ormoceras tenuifilum Hall.
Lituites undatus Emmons.
Cyrtoceras subannulatum D'Orbigny.
Illsenus ovatus Conrad.

ANTHASPIDELLA nov. gen.

Sponges compound, saucer or funnel-shaped, supported by a
short sub-cylindrical stem. Both surfaces of sponge wall with
numerous inosculating radiating channels. As growth proceeds
those of the upper surface are arched over by the spicular skel-
eton and form radial canals, which, by bending downward at
their outer extremities, pass through the sponge wall, and open
into the channels of the lower surface. These radiating canals
are closely arranged in vertical series, each series being sepa-
rated from the others by vertical sheets composed of spicular
structure. The canals of each series communicate with each
other sparingly, but more freely with those of the next series.
Upper surface presenting a greater or less number of oscula,

SPONGES. 257

each provided with its individual system of radiating channels,
which, however, gradually merge into the prevailing radiate ar-
rangement. The depressed central portion of each osculum is
occupied by the apertures of a limited number of rather large
thin-walled vertical tubes, which traverse the sponge wall to
half or less than half its thickness. Those in the central oscu-
luni extend throughout the stem.

Interior skeleton composed of } — { shaped spicules, arranged in
linear series so as to leave minute canals of triangular, quad-
rate, or polygonal form. Just below the centre of a vertical
section of the sponge wall, these capillary canals run nearly
parallel with the lower margin. From this region they proceed
in a gradually diverging and curved direction to each surface.*

Both surfaces sometimes covered with a dense dermal layer.

Types, A. florifera and A. mammulata.

The minute internal structure of the species referred to this
genus and described on the following pages, is practically iden-
tical in all. This we believe to be largely due to the destruc-
tion of the finer details of structure, consequent to the replace-
ment of the original siliceous material by crystalline calcite.
The same may be said of the spicular mesh of Zittelella, Edrio-
spongia and Streptosolen when compared with that of Anthas-
pirtella. We were, therefore, obliged to depend entirely upon
external features and variations in the systems in distinguish-
ing the genera and the species referred to each. As these char-
acters are often unreliable among the sponges, we will not be
surprised if future investigations prove that we have made
more species and, perhaps, even genera than was necessary.
The field being comparatively new and exceedingly difficult, we
expect our work to prove faulty in some respects; yet, what-
ever errors we may have fallen into, we will find consolation in
the conviction that we have done the best we could under the
circumstances.!

* For further information respecting the interior see discussion on the Anthispidel-
lidae, on pages 221 to 226,

t Since the above wa- written Mr. Ulrich visited Dixon and succeeded in collecting
a considerable number of these sponges. Their study proved very gratifying to us,
since we found no difficulty whatever in placing every specimen save a few, belonging
to as yet undescribed species.

—32

258 PALEONTOLOGY OF ILLINOIS.

ANTHASPIDELLA MAMMULATA U. & E.

PI. I, Pig. 1, la, Ib, Ic, Id.

Sponge having the shape of a widely expanded funnel, with
the margin abruptly rounded. Upper surface deeply concave.
Oscula numerous, occurring at intervals varying from 5 to
20 mm. They occupy the summits of more or less elevated
monticules, and when the compact dermal layer is preserved,
their abruptly depressed apertures, having a diameter of 2.5 mm.
or less, are rounded and sharply margined. When the outer
layer is wanting, they are surrounded by from six to ten radiat-
ing canals. As usual, the oscula are most numerous in the
central portion. The furrows of the radiating canals inosculate
rather freely. Under surface comparatively even, with the sides
nearly straight or faintly convex, and marked by radiating
furrows, of which seven to nine occur in 0.5 of an inch. The
margins of these furrows may be entire, more often serrated, and,
less commonly, connected with those adjoining by transverse
canals.

The canal system, as brought out by sections, consists princi-
pally of the radiating canals, which, penetrating the sponge
wall in a curved direction and a;t right angles to the minute
canals formed by the spicular mesh, are arranged in vertically
superimposed series. Those of adjoining series are connected
with each other at more or less frequent intervals by short
canals, arranged in such a manner that they might be mistaken
for another series of canals running parallel with the capillary
canals. This, however, is not their true nature, as the section
clearly shows that each of the supposed canals is formed by a
series of closely approximated connecting canals. (See PI. I.
fig. Ib.)

Diameter of an ordinary sized example, 100 mm.; entire height
about 38 mm.; depth of cup, 25 mm.; thickness of wall from 7
to 10 mm.

The greater concavity or depth of the upper surface and
general form of the sponge, separate A. mammulata from such

SPONGES. 259

species as A. florifera, A. scutula and A. parvistellata, while
the pustulate form of the oscula furnishes the most characteristic
feature of the species.

Position and locality: Twenty-five feet above the base of the
Trenton limestone, near Dixon, 111.

ANTHASPIDELLA FLORIFERA U. & E.

PI. I, Fig. -2. and PL IY. Fig. 2.

Sponge saucer-shaped, usually very shallow and abruptly ex-
panded above the short stem. Margin sharp or narrowly
rounded. Under surface comparatively even, sometimes with a
fesv irregular shallow radiating and concentric depressions. The
channels on the under surface are united at frequent but irregular
intervals by cross furrows. Their width usually equals about
one-half that of the intervening wall-substance. Upper surface
gently concave, with a central osculum, surrounding which, at
a radius of from 18 to 25 mm., is an irregular circle of similar,
but slightly smaller oscula. In very large specimens a second
series is developed at about the same distance from the first
circle. In the first circle the oscula number from six to eight
and are separated from each other by 12 mm. or more. The
center of each is slightly, but rather abruptly depressed, and
occupied by the apertures of a group of six or more vertical,
very thin-walled canals, about 0.7 mm. in diameter.

Radiating in all directions from the oscula, the surface pre-
sents a series of canals which sometimes anastomose rather
freely with each other, but, more commonly, are connected at
more or less remote intervals by transverse furrows or canals.
The width of these channels sometimes nearly equals that of the
intervening sponge tissue, but generally is not more than half
as wide. In the central portion of the sponge seven or eight of
the radiating canals may be counted in the space of 10 mm.,
while near the outer margin five or six suffice to fill the same
space. A section, dividing the sponge vertically through the
centre, shows that the tubes occupying the central osculuin are
continuous from the base of the stem to the upper surface,
while those occupying the other oscula do not penetrate the

260 PALEONTOLOGY OF ILLINOIS.

walls of the sponge more than half its thickness. On each side
of the central tubes the section shows a number of radiating
canals at distances apart of 1.2 mm. or more, which run
parallel with the upper surface, and therefore curve downwards
at their outer ends, and open into the radiating furrows ob-
served on the lower surface. They are occasionally united with
each other by vertical, but, more frequently, by transverse
canals. A distinct series of capillary canals is formed by the
regular arrangement of the spicular tissue. These proceed to
each surface in gradually diverging curved directions from a
line parallel with, and much nearer the lower than the upper
surface.

Entire height of an ordinary specimen 37 mm.; height of
stem 12 mm.; diameter of cup 88 mm.; depth of cup 10 mm.;
thickness of wall about 12 mm.

More specimens of this beautiful species were obtained than
of any of the others here described. They are easily recognized
by the comparatively few oscula, and regularity of the radiating
canals around the large central one, which is also more defined
than in any of the other species.

Position and locality: Twenty-five feet above the base of the
Trenton limestone near Dixon, 111.

ANTHASPIDELLA PARVISTELLATA U. & E.

PI. I, flg. 3.

Sponge patelliform, very shallow and abruptly expanded
above the short stem. Walls thin, with a few irregular concen-
tric and radiating depressions on the lower side. Margin sub-
acute. Upper surface gently concave in the central portion, and
slightly convex towards the margin. Oscula comparatively
small, numerous, numbering at least seventy. Nearly all of
these occur in the inner two-thirds of the diameter, they being
but sparingly or not at all developed in the outer third. Where
they are most numerous, more than twenty may be counted in
one inch square. Each is surrounded by from five to nine radi-
ating furrows, giving them a decidedly stellate appearance. Be-

SPONGES. 261

t\veen and beyond the oscula the surface is radiately furrowed.
The furrows are usually half the width of the intervening
sponge substance. They bend down toward the lower surface
more abruptly than usual. It is due to the last fact that when
but slightly worn, the sponge presents the appearance of being
traversed by vertical canals, the rounded apertures of which
are closely arranged in radiating series (see PL I, fig. 3.) The
canals on the lower side of the sponge wall are usually irregu-
larly serrated at their sides, or they may inosculate with each
other without losing their distinctly radial character. From
six to eight occur in a space 10 mm. wide.

The internal structure conforms with that given for the genus.

Diameter of a specimen 88 mm.; thickness of wall from 5 to
8 mm.; height of expanded portion of sponge 13 mm.; height
of stem unknown, apparently not more than 15 mm.

The small size and great number of the oscula characterize
this species, and serve to distinguish it from A. scutula. and
A. florifera, both of which have a somewhat similar form.

Position ;uid locality: Twenty-five feet above the base of the
Trenton limestone, near Dixon, Illinois.

AXTHASPIDELLA SCfTULA U. & E.
PL m. fig. 1. la.

Sponge large, saucer shaped, rather shallow, and abruptly ex-
panded above the short sub-cylindrical stem. Margin sharp.
Under surface veiy uneven, with rough, irregular prominences
and depressions, which are often arranged in a somewhat con-
centric manner. On account of the irregularity of the under
surface, the radial character of the furrows is less distinct than
usual. Upper surface concave throughout, excepting just at the
inside of the outer margin where it is convex. Oscula of mod-
erate size, numerous, from 5 to 12 mm. apart, and surrounded
by from eight to fifteen radial canals. On account of the great
number of the oscula, the radiating furrows or canals inoscu-
late freely with each other. This is especially the case over the
central region of the surface ; nearer the margin their arrange-
ment in series radiating from the centre of the sponge becomes
more apparent.

262 PALAEONTOLOGY OF ILLINOIS.

Canal system and interior skeleton like that of A. mam-
mulata.

Diameter of a large specimen 168 mm.; entire height about
50 mm.; night of expanded portion 37 mm.; depth of cup 28
mm.; thickness of wall from 10 to 18 mm.

This species is readily distinguished from all others here des-
scribed, by its extremely roughened under surface.

Position and locality: Twenty-five feet above the base of the
Trenton limestone, near Dixon, Illinois.

ANTHASPIDELLA GRANDIS U. & E.

PL II. fig, 2, 2a.

Sponge very large, consisting of a discoidal expansion, the
upper surface of which is flat, or very slightly concave. Outer
margin sub-acute or rounded. The entire upper surface is
marked by frequently connected radiating furrows, the regu-
larity of which is more or less disturbed at very unequal inter-
vals by the development of an osculum. Oscula rather incon-
spicuous and unequal, from 12 to 50 mm. apart. Lower sur-
face somewhat roughened, and traversed by frequently con-
nected or only serrated radiating furrows. Over limited portions
of the surface they are sometimes almost labyrinthically inter-
twined, when their radial character may be entirely obliterated
or, at least, much obscured.

No complete specimen of this species has as yet been found,
but judging from the fragments before us the sponge attained a
diameter of no less than 500 mm., while its entire height does
not appear to have been more than perhaps two or three
inches. The fragments show further, that, though the sponge
was extremely expanded, the thickness of the wall never exceeded
20 mm., while it is usually not more than 12 or 15 mm.

The shape and large size of the sponge, as well as the irregular
disposition of the oscula, serve readily to distinguish this spe-
cies from any of the associated forms.

Position and locality : Twenty-five feet above the base of the
Trenton limestone, near Dixon, Illinois.

SPONGES. 263

ANTHASPIDELLA FIRMA U. & H.

PL H, fig. 3, 3a.

Of this sponge the specimen figured is the only one observed.*
Its shape is obliquely depressed-obconical, the cup shallow, and
its margin acute, the stem strong, and apparently very short.
The under surface shows two faint constrictions, besides several
nodular protuberances. The furrows are strong, four to six in
10 mm., and more or less irregularly interrupted, being espe-
cially so upon the shorter side. The comparatively large, oval
or circular mouths of the radiating channels, are visible in the
bottom of the furrows. About seven occur in 10 mm.

The oscula of the upper surface are deeply impressed, irregu-
larly stellate, of moderate size, and the twenty-seven that can
be determined are confined to the inner two-thirds of the cup;
the canals which radiate from them, are strong and usually
proceed but a short distance when their diameter is diminished,
and their identity lost in the confused canal-network prevailing
over the central portion of the surface. It is only toward the
margin of the cup that the channels assume a common radiate
arrangement : yet. even here, they inosculate rather freely.

The canal system, as shown by cutting the specimen vertically
through the centre, proves to be in all important particulars
considerably like that of A. florifera. The canals, however, are
larger and the radiating canals less curved downward at their
outer ends, appearing also, much less continuous in the section.

Height of sponge about 50 mm.; greatest diameter of cup,
92 mm.; depth of same 13 mm.; diameter of stem, where broken
about 25 mm.

The canals of this species are larger and more widely separ-
ated than in any other of the species here described, and as
the type specimen differs more or less obviously in other re-
spects from them, it is difficult to decide to which A. firma is
the most closely related. These peculiarities, however, are only
of specific importance, and the species is clearly congeneric with
A. mammulata.

* Another specimen of this species was collected lately by Mr. TJlrich.

264 PALAEONTOLOGY OF ILLINOIS.

Position and locality: Twenty-five feet above the base of the
Trenton limestone, near Dixon, Illinois.

ANTHASPIDELLA FENESTRATA U. & E.

PI. ii, fig. i.

Sponge infundibuliform or campanulate, with the cup rather
deep. Above the comparatively large and irregularly sub-cylin-
drical stem, the sides diverge with a gentle outward curve to
the acutely rounded and slightly oblique margin of the cup.
Wall about 10 mm. in thickness. Outer or under surface, where
unworn, with distinct vertical furrows, seven or eight in 10
mm., into which the radiating canals open. On the stem the
furrows are irregularly disposed and united at frequent inter-
vals by short transverse channels.

Upper surface deeply concave, with a large central osculum,
from which ten or twelve strong channels radiate. Over fifty,
similar, but smaller oscula are unequally distributed over the
remaining surface of the cup; each is surrounded by from five
to ten radiating channels, which proceed but a short distance
before they merge into the principal furrows; these, despite the
numerous interruptions, always maintain a general outward
direction from the centre of the cup.

Entire height of a good example about 90 mm.; greatest
diameter at margin of cup 80 mm.; diameter of stem 20
mm. or a little less; depth of cup about 23 mm.

In external form this species somewhat resembles both A.
obliqua and A. magnifica. From the first of these it differs in
its larger size, less expanded cup, and much more numerous
oscula, while the radiating furrows communicate by means of
transverse channels rather than by anastomosis. From A. mag-
nifica it is distinguished by its smaller size, furrowed outer sur-
face, and generally larger canals and oscula.

Position and locality: Twenty-five feet above the base of the
Trenton limestone, near Dixon, Illinois.

SPONGES. 265

ANTHASPIDELLA OBLIQUA U. & E.

PL IY, flg. l.la.

Sponge funnel-shaped, gradually expanding above the sub-
cylindrical stem. Margin of cup narrowly rounded and some-
what oblique. Upper surface depressed, and sloping gradually
towards the centre, where the best specimen shows a group of
three oscula, each surrounded by from twelve to sixteen radi-
ating canals, which inosculate with each other and bifurcate
rather freely toward the outer margin of the sponge. The
sponge tissue between the canals is thinner than usual, being
generally of less width than the diameter of the canals. Outer
and under surface apparently smooth or even, with the sides
concave and traversed by vertical furrows in which the closely
arranged apertures of the radiating canals, which have pene-
trated the walls of the sponge from the upper surface, are
plainly to be seen. On portions of the stem the canals are very
irregular.

Only two imperfect specimens of this species have been observed
but as they show decided peculiarities, it has been thought
desirable to describe them. Judging from the form of the speci-
mens, the affinities of the species lie with A. fenestrata, from
which, however, it is easily distinguished by the smaller size,
more expanded cup, and different arrangement of the canals
and oscula on the upper surface.

Diameter of cup of best specimen 40 mm.; entire height 53
mm.; diameter of stem about 15 mm.; depth of cup 9 mm.

Position and locality: Twenty-five feet above the base of the
Trenton limestone, near Dixon, Illinois.

ANTHASPIDELLA? MAGNIFICA U. & E.

PL VIII, fig. 2, 2a, 2b. 2c.

Of this fine species the collection affords but a single example,
which is figured, partly in outline, on plate VIII. By sawing it
vertically through the centre we were enabled to free the deep
cup of the enclosed rock, and to trace out the canal systems
which are well shown in the wall sections, The entire specimen
-33

266 PALAEONTOLOGY OF ILLINOIS.

is funnel or goblet-shaped, the stem strong, sub-cylindrical,
irregularly expanded below, and marked by the more or less
confluent and irregularly distributed apertures of small canals,
rarely more than 0.5 mm. in diameter. Above the stem on the
outer side of the cup, the same irregularity pertains to the dis-
tribution of the canal openings and continues to within one
inch of the cup margin, where they arrange themselves into
vertical series. The outer surface of the cup, especially just
above the stem, is faintly mammulated, the broad eminences
low and with an obscure vertical arrangement. The cup is deep,
and on its sloping sides presents a large number of small
slightly raised stellate oscula, 1.5 to 2 mm. in diameter; ten
or more may be counted in a space one inch square. Below the
dense cortical substance which covers the intermediate spaces
in the perfect state, the canal furrows inosculate freely, but a
tendency to follow lines radiating from the centre of the cup to
the margin is always maintained. A vertical section of the
specimen shows that the central portion of the stem is traversed
by vertical canals opening into the base of the cup. The same
series of canals continues on into the walls of the cup. Here
they originate along an imaginary line dividing the sponge wall
into two layers, an inner one that nearly maintains its thick-
ness throughout the cup-wall, and a thinner outer layer that
gradually diminishes in thickness from the base of the stem to
the margin where it is wanting. The canals in question pass
through the inner layer in a curved direction and open at right
angles with the surface into the cup cavity. The outer layer is
traversed in an opposite direction by similar, but shorter and
more numerous canals. A third series is shown in the upper
portion of the section figured (PI. VIII, fig. 2c). These proceed
apparently from the oscula, and passing through the inner
layer in an opposite direction from those already described, ter-
minate, at the line marking the beginning of the outer layer.
The spicular structure does not differ, so far as observed, from
that of A. florifera and the other species.

Height of specimen 150 mm.; diameter of stem 35 mm.; ap-
proximate diameter at cup margin 140 mm.; depth of cup 70
inni.; average thickness t)f cup wall 17 mm,; thickness of inner
layer about 10 ram,

SPONGES. 267

This species differs considerably in its canal system from A.
florifera and A. mammulata. In those species the vertical
canals are almost entirely restricted to the oscula, while the
radiating canals are much the more numerously met with in
sections. The opposite is the case with A. magnifica, since the
radiating canals are but rarely seen in the sections, while the
vertical ones are numerous. None of the other species seem to
have been provided with an outer layer like that described
above, as in all, (so far as their preservation will admit of de-
termining this point) the radiating canals open on the outer
surface into the vertical grooves. Except at or near the margin
of the cup, this is not the case in A. magnifies,, since in this
species they do not pass through the outer layer. The func-
tions of the latter was probably the same as that of the ordi-
nary dermal layer of the sponges. The differences may indicate
another genus of this peculiar family of sponges, but till they
are proven to be of generic importance by finding them in other
forms, we prefer to place the species, at least provisionally, with
AnthaspideHB.

Position and locality: Twenty-five feet above the base of the
Trenton limestone, near Dixon, Illinois.

ZlTTELELLA nOV. gen.

Sponges simple, pedunculate and attached, varying in shape
from depressed obconical, turbinate or sub-spherical, to sub-
cylindrical : rarely lobate. Upper surface with a shallow central
depression into which a variable number of thin-walled vertical
tubes, extending through to the base of the sponge, open.
Canal system consisting principally of a series of radiating
canals, which may inosculate freely with each other, or only to
a limited degree in their passage through the walls of the sponge
from the outer surface to the vertical central tubes. The radi-
ating canals are closely arranged in vertical series, separated
by spicular tissue from one to three times as wide as the canals.
This arrangement of the canals gives the sponge the appear-
ance of being divided by vertical fissures. Interior skeleton as

268 PALEONTOLOGY OF ILLINOIS.

in Anthaspidella, excepting that the capillary canals run parallel
with the sides of the sponge wall, and open only at the upper
surface.

Under surface sometimes covered with a dense dermal layer.
Type Z. typicalis*

ZlTTELELLA TYPICALIS U. & E.
PL V, fig. 5, 5a.

Sponge vase or funnel-shaped, with a comparatively long sub-
cylindrical stem. Upper surface slightly depressed, and marked
by somewhat regular radiating canals uniting more or less freely
with each other by means of lateral divisions, or by inoscula-
tion. The width of the channels is about 0.6 mm., while from
eight to ten occur in 10 mm. The depressed centre of the cup
surface exhibits the apertures of nearly fifty vertical tubes, each
about 0.8 mm. in diameter, having very thin walls. The sides
of the sponge spread rapidly above the stem, and usually ex-
hibit a number of shallow vertical depressions, as well as the
vertical channels. About five of the latter occur in a space 10
mm. wide. The vertically arranged mouths of the radiating
canals are shown in the place of the channels when the speci-
mens are worn; six or seven in a series 10 mm. long. On the
stem the channels are short, numerous, and irregularly arranged.
From the fact that the radiating channels of the upper surface
are more numerous than those on the sides, it appears that
many of the radiating canals are blind, (L e. terminate before
reaching the outer surface) or, that all of the radiating channels
are not converted into internal canals.

The best specimen (a small one) is 44 mm. in height, and 60
mm. in diameter; the stem about 18 mm. long, and 20 mm. in
diameter.

The above describes the typical form of the species, but the
collection contains a number of sponges from the same locality,
which, while they do not appear to be distinguishable by specific

* The absence of radiate oscula distinguishes this genus from Anthaspidella.
Aulocopium and Climacospongia, have different canal systems.

SPONGES. 269

characters, can, nevertheless, be recognized by peculiarities of
form and other features of minor importance. For these we
propose the varietal names pistilliformis, turbinata and sub-
rotunda.

var. PISTILLIFORMIS U. & E.

PL V, fl«. 4.

This variety is distinguished from the typical form of the
species by having a more distinct stem, the radiating channels
less regular, and oftener united by inosculation, the vertical
cloacal tubes somewhat larger and much less numerous, and
the upper surface convex instead of flat. The three specimens
referred to the variety are also smaller, the largest being only
36 mm. high, while the greatest diameter is 35 mm.

var. TURBINATA U. & E.

PL V, Fie. 3, Sa, 3b, 3c. 7. 7a.

The turbinate form of the sponge is the distinguishing charac-
ter of this variety. In all other respects a close resemblance to
the typical form prevails. Six specimens are referred to the
variety. The two examples, illustrated on plate V, are of
medium size.

var. SUBROTUNDA U. & E.

PL V, Fte. 2, 2a.

This form is related to var. turbinata, but differs from it, and
to a greater degree from var. pistilliformis, and the typical
form of the species, in the subglobose body of the sponge. The
central or cloacal depression is deeper than usual, and it does
not appear that the sponge was prolonged below into a stem.

We have seen only two specimens which could be referred to
this variety, and both are much worn and imperfect. In their
present condition they present very little resemblance to Z.
typicalis, but fearing the differences might in part be due to the
poor state of preservation, and as the var. turbinata is an in-
termediate form, we preferred to class them as above.

270 PALEONTOLOGY OF ILLINOIS.

This species and varieties is, perhaps, more closely related to
Z. trentonensis Worthen sp.*, than to any other of the species
found at Dixon, 111. They are easily distinguished by the de-
pressed obconical form of that species, and the very short or
rudimentary stem. The channels are also separated by wider
interspaces than in the present species.

Position and locality: Twenty,five feet above the base of the
Trenton limestone, near Dixon, 111.

ZlTTELELLA LOBATA U. & E.

PL IV. Figs. 3, 3a, 3b, 3e.

Sponge of an irregular obconical form, with the upper surface
flattened, the sides or lower surface deeply sulcate or irregularly
lobate, and abruptly expanded above the stem. The radiating
channels of the upper surface are moderately regular, with an
average of seven in 10 mm. The cloacal tubes are 1 mm. in
diameter, and ten or more in number. The outer portion of
the upper surface also exhibits a number of shallow impressions,
arranged in an irregularly radiate manner around the centre.
On account of the irregular lobate character of the under sur-
face the channels here are also irregular. In the perfect state
they are covered by a dermal layer, the characters of which have
not been ascertained.

A large specimen has a height above the stem of 30 mm.; the
greatest diameter of the upper surface is 90 mm. The stem is
compressed and of unknown length. The longest and shortest
diameters are, respectively, 22 mm., and 13 mm.

This well marked species is readily distinguished from all
associated forms by the irregularly lobate character of the under
surface.

Position and locality: Twenty-five feet above the base of the
Trenton limestone near Dixon, 111.

* Cnemidium? trentonensis, Worthen, 111. Geol. Sur, Bep'ts, Vol. VI. p. 491. 1875.

SPONGES. 271

ZlTTELELLA INOSCULATA U. & E.
PL V. Figs. 6-6a.

Sponge pestle-shaped, the stem large, subcylindrical, the upper
portion expanded, with the margin narrowly rounded into the
convex upper surface. The vertical channels on the sides of the
sponges are very irregular and frequently united. The inter-
spaces vary in width from one to three mm., and the number
of channels in a space 10 mm. wide, from four to seven, while
the average number is about five. The central portion of the
upper surface is abruptly depressed, the depression stellate, and
exhibiting at the bottom the mouths of from four to eight
cloacal tubes. The radiating furrows are wavy, bifurcate and
inosculate freely with each other, and from 0.5 mm. to 0.8 mm.
in width. The interspaces which are narrow wedge-shaped in
the region about the cloacal depression, vary in width from 0.2
mm. to 2 mm., being widest at the margin.

Height of a medium sized specimen, 33 mm.; diameter of stem
varying from 14 to 18 mm.; height of same 21 mm.; diameter
of upper portion, about 27 mm. Another example is about 25
mm, in diameter; height of expanded upper portion 10 mm.;
diameter of stem where it is broken from the body of the sponge,
about 11 mm. The form of this specimen appears to have been
very much like that of Z. typicalis var. pistilliformis, figured on
the same plate with this species (PI. V, fig. 4,).

The distinguishing characters of the species are found in the
wavy and inosculating surface channels, and the generally wider
interspaces. The form of the sponge approximates to that of
Z. typicalis var. pistilliformis, but none of the four specimens
are so much expanded above. A comparison of their respective
surface channeling^ will readily distinguish them.

Position and locality: Twenty-five feet above the base of the
Trenton limestone near Dixon, 111.

EDRIOSPONGIA nov. gen.

Sponge massive, lobate, attached by a broad base, with the
sides irregularly indented. Canal system irregular, consisting

272 . PALAEONTOLOGY OF ILLINOIS.

of closely arranged radiating canals, connected by tortuous
vertical canals passing through them. Minute canals, formed
by the arrangement of the spicules in linear series, traverse the
sponge in a direction parallel with the radiating canals. When
perfect the sides of the sponge are covered with a minutely
porous dermal layer. When this is removed the irregularly
arrayed apertures of the radiating canals are exposed. Spicu-
lar structure between the canals, of unequal thickness, usually
narrow.

The distinguishing characters of this genus may be summed up
as follows: (1) The massive form, (2) broad base, (3) absence
of stellate oscula and vertical cloacal tubes, and (4) the irregular
arrangement of the canals, when compared with those of An-
thaspidella and Zittelella. From Streptosolen the genus is
separated by the three peculiarities first noted, as well as by
the smaller and less tortuous radiating canals.

EDKIOSPONGIA BASALIS U. & K.

PL VI, fig. 1. la, lb, lc.

Sponge massive, irregular in outline, and attached to foreign
bodies by a broad base; the sides are irregularly and often
deeply indented, so as to impart to the mass a rudely pillared
aspect. Upper surface with irregular depressions, but without
oscula save those of the radially arranged vertical canals.
These usually alternate with the radiating canal furrows, and
form close series between two of the latter. Five or six mouths
occur in the length of 5 mm., while the diameter of each is
about 0.6 mm.

Upon grinding the surface it will be noticed that the radiate
furrows are replaced by rows of vertical canal apertures, and
the series of the latter by radiating canals. This changing
from one to the other repeats itself if the grinding is continued,
and proves that the two sets of canals pass through each other,
and are alternately developed at the surface. The sides of the
sponge, when the dermal layer is removed, often show the sub-
Circular mouths of the radiating canals arranged in irregular

SPONGES. 273

vertical series. Portions of the more or less tortuous vertical
canals also may be presented to view. Generally, however, the
sides present a very irregular network of canals.

Height of largest example varying between 18 and 40 mm.;
greatest width about 90 mm.

The three specimens of this species contained in the collection
before us, are in too poor a state of preservation to admit of
satisfactorily determining all the details. One of them is very
det-Hptive. as it is attached to the lower surface of a species of
Anthaspidella and has adapted itself so neatly to it that the
osculiferous face was supposed to belong to the Edriospongia.
This mistake was not discovered till some time after the speci-
men had been lithographed (PI. VI, fig. 1, la) and the plate
printed. It then occurred to us to saw the perplexing specimen
vertically through the centre. When this was accomplished the
duplex character was made manifest, as the section clearly
shows a divisional line between the two sponges. Another diffi-
culty, now presented, was to determine whether the Edriospongia
had grown upon the Anthaspidella, or the former been accidentally-
deposited upon the upper surface of the latter. All the facts
seem to point to the second explanation as the true one. Every
character of the lower surface of the specimen as it is repre-
sented by fig. la, brings evidence against the conclusion that
we are dealing with the upper surface of the sponge, but on
the contrary, agrees in every respect with our idea of the base
of a parasitic sponge. It therefore appears that during the
lifetime of the Edriospongia the Anthaspidella was deposited
upon its upper surface, without seriously interfering with the
functions till the gradual increase of the sponge mass had
stopped the water circulation by closing the canal outlets.

Position and locality: Twenty-five feet above the base of the
Trenton limestone, near Dixon. Illinois.

STREPTOSOLEX nov. gen.

Sponges simple or compound, obconical, pedunculate. Central
oscula showing the mouths of five or six thin walled tubes,
which extend'through the sponge to the base. The oscula are
-34

274 PALEONTOLOGY OF ILLINOIS.

surrounded by an irregularly radiating series of large canals;
between these are also a few apertures of vertical canals. Sides
of sponge with very irregular branching canal furrows. Minute
structure of skeleton like that of Zittelella and Anthaspidella.

The character principally relied upon in distinguishing this
genus from Anthaspidella, is found in the very irregular dispo-
sition of the canals. The radiating canals are not, as in that
genus and Zittelella, arrayed in vertical series, but pass through
the sponge ma,ss in every direction, and the vertical furrows, so
characteristic of those genera, are therefore wanting.

STREPTOSOLEN OBCONICUS U. & E.

PL IV, fig. 4, 4a, 4b.

Sponge obconical, gradually widening above the strong and
slightly expanded base. Upper surface flat or slightly depressed
with the margin rounded. The collection contains two speci-
mens of which the smaller one was figured. This has but one
osculum, sub-centrically situated, and around it a number of tor-
tuous interrupted and branching radiating canals. The larger
specimen has three oscula, each of which is surrounded by its
own irregular system of radiating canals. The average width
of the canals is about 1.2 mm. The sides of both specimens
present a very irregular system of tortuous branching canal
furrows. Near the base of the larger specimen there are evi-
dences of a dense dermal layer. The dimensions of this example
are as follows: height 75 mm.; greatest width about 60 mm.;
diameter of stem 17 mm. by 24 mm.

None of the associated sponges resemble this species suffi-
ciently to necessitate detailed comparisons. The irregular in-
tertwining of the canals will distinguish it at a glance.

Position and locality: Twenty-five feet above the base of the
Trenton limestone, near Dixon, Illinois.

CALATHIUM?? (?ZITTELELLA) INFELIX U. & E.

PL V, flg. 1. la.

Of this species only two imperfect examples have been observed,
but as they seem to be quite different from any of the associ-

SPONGES. 275

ate<] sponges, it was deemed advisable to name and illustrate
them. The form is obliquely conical, about a.s wide as high;
the cup very deep, with the margins rounded. Sides of cup pre-
senting the apertures of large radiating canals, arranged seri-
ally in the bottom of vertical channels, four or five in 10 mm.
The outer surface of the sponge wall is much weathered, but
preserves enough to show that though the radiating canals
pass through the wall they are less regularly arranged here
than on the inner surface. The spaces between the canals are
poriferous, but the form of the spicules could not be determined,
with certainty. A transparent section seems to show, however,
that they are not unlike those of the ANTHASPIDELLID.E. Sponge
wall gradually increasing in thickness from below up\vards.
The greatest thickness, 10 mm., is in the upper one-third of the
height.

This sponge is placed provisionally in the genus Calathium of
Billings, because it is most probably congeneric with his C.
ruiicidense, from the Chazy. Question signs are added because
we believe C. formosuw, the type of the genus, is generically
distinct from these forms, but till the spicular structure of the
various species has been determined, it will be impracticable to
separate the groups. Perhaps the genus Zittelella should be
extended so that it would include species of this type.

Position and locality: Twenty-five feet above the base of the
Trenton limestone, near Dixon, Illinois.

HINDI A IX.EQVALIS F. ».V: E.

PI. H. fig. 4. 4a, 4b.

Sponge free, of spherical form, with the surface evenly rounded.
The diameter of the largest specimen is 13 mm. Other examples
apparently belonging to the same species, vary from 7 to 10
mm.

The centre of the sponge is occupied by loose tissue, from
which extend small straight canals to all parts of the surface.
The radiate canals increase in number, and very slightly in size,
a.s the sponge grows larger, are sub-circular in section, and vary

276 PALAEONTOLOGY OF ILLINOIS.

in width from 0.2 to 0.7 mm.; their walls are thin and consist of
cemented spicules. The skeleton, being calcined, gives but a
faint idea of the individual spicules.

The internal character of the species, as they appear in thin
sections, are well shown in figs. 4a and 4b. In transverse sec-
tions, the angles of junction between the canals, are alternately
composed of: ( 1 ) clear crystalline calcite, representing the nodes
of the spicules, and (2) the matrix which passes through the
connecting pores. In fig. 4a the latter are represented by a
darker shade. It would, perhaps, have been better to have
left them out of the drawing altogether, as the irregular shad-
ing by which we intended to imitate the limestone matrix,
might be interpreted to represent details, of skeleton structure
not intended.

The distinguishing feature of this species is found in the un-
equal size of the radiating canals. The larger ones are gener-
ally surrounded by one or two series of the smaller canals, but
their arrangement with relation to each other is quite as vari-
able as their width.

Position and locality: Twenty-five feet above the base of the
Trenton limestone, near Dixon, Illinois.

STROTOSPONGIA nov. gen.

Sponges compound, funnel-shaped, composed of thin, intri-
cately intertwined vertical leaves. The upper surface with more
than one osculum, around which the undulating vertical leaves
are arranged in a radiate manner. Cloacal depressions of vari-
able depth; the apertures of several vertical tubes occupy the
bottom of each. Lower or outer surface with large sub-circular
and closely arranged canal apertures, arranged in somewhat
regular longitudinal series, while the interstices between them
are occupied by smaller canal apertures of variable size and
form.

Vertical sections show that the sponge wall is travered by
labyrinthically intertwined canals, having irregularly perforated
thin walls.

SPONGES. 277

Owing to changes produced during the process of fossilization
the minute structure of the canal walls cannot be determined
satisfactorily. Where the walls are thinnest, traces of the spi-
cules are preserved. They appear to have been very minute,
and mainly three-rayed. Also a few extremely small uniaxial
spicules seem to belong here.

In the form and general aspect of the sponge, Strotospongia
resembles species of Anthaspidella so closely, that the utter
disagreement in their respective internal structures (so far as it
has been determined) is very surprising. On the other hand,
we are again surprised to find that the internal structure of Stro-
tospongia corresponds very closely with that of the massive
sponges for which Mr. S. A. Miller proposed the genus Dystac-
tospongia. Both of these genera, we believe, belong to the CAL-
CISPONGLE, which they resemble more than any other group of
sponges. At any rate, none of the characters so far determined
present any serious objections to our view, but on the contrary
all seem to justify a provisional classification with the calcare-
ous sponges.

STROTOSPONGIA MACULOSA U. & E.

PI. VIII, fig. 1, la, Ib. Ic, Id,

Sponge depressed funnel-shaped, expanding rapidly above the
sub-cylindrical stem, which is of unknown length. Upper sur-
face concave, with the margin acutely rounded. Near the centre
there is a deep cloacal cavity or osculum, while six others, of
smaller size, and less deep are situated at varying distances
from the central osculum. Around each there is a series of
thin-walled canals, arranged in a radiate manner, from 1 to 1.5
mm. wide. The radiating canals extend but a short distance
from the oscula when they bend downward and are lost in the
confused plexus which prevails throughout the interior of the
sponge. Beyond them the thin sponge substance forms a very
irregular network, with large angular meshes.

The under surface exhibits the apertures of numerous canals,
0.7 to 1.2 mm. in width, which are arranged in subregular longi-
tudinal series on the expanded portion of the sponge. On the

278 PALEONTOLOGY OF ILLINOIS,

surface of the stem their arrangement is much less regular,
while they are also somewhat larger aud more angular than those
occupying the space for some distance above the stern. Here
their mouths are sub-circular, and separated by sponge tissue
less than half their diameter in width. Near the margin of the
upper surface the canal apertures again become more angular,
and the sponge substance thinner. Numerous smaller canal
apertures occupy the spaces between the larger caimls.

A vertical section shows that the sponge walls are traversed
by labyrinth ically intertwined canals. The separating sponge
substance, which is generally not more than 0.1 mm. thick, has
been replaced by crystalline calcite, and the process has effectu-
ally destroyed nearly all the finer details of structure. Where
the walls are thinnest, or less compact than usual, obscure
traces of the spicules and sponge fibre are preserved. So far as
the unsatisfactory conditions will admit of determining their
characters, it seems that the fibres contained both three-rayed
and uniaxial spicules.

The above describes the characters of the specimen we have
illustrated. The collection contains, besides, two other examples
which differ considerably in the size and arrangement of the
canals, and may belong to another species of the genus.
Although we were tempted to add another species to this pecu-
liar genus, we have concluded to await the discovery of other
specimens, before deciding them to be distinct.

Position and locality: Twenty-five feet above the base of the
Trenton limestone, near Dixon, Illinois.

DYSTACTOSPONGIA MINOR. U. & E.

PL Yin, Fig. 3. 3a, 3b.

Sponge lobate massive, composed of irregular vertical leaves,
which combine to form a tubular mass. The tubes or canals
radiate from the base to the upper surface of the specimen,
where their walls, which have a thickness varying from 0.1 to
0.4 mm., present the appearance of short, beaded lines of cal-
cite, forming an incomplete net work, with small and irregular
meshes, not exceeding, apparently, 1 mm. in width.

SPONGES. 279

in vertical sections the canal walls decrease slightly in thick-
ness from below upwards. They are pierced at frequent but
unequal intervals by large irregular openings. The canal cavi-
ties are traversed by fine branching or simple fibres of calcite,
which we suppose to represent spicules. In transverse sections
the sponge substance is represented by small irregular masses
of crystalline calcite.

Of this species Ave have seen only the small lobate example,
illustrated on plate VIII.* The figure gives an oblique view of
the specimen and shows, on the left side, vertical canals running
from the base to the rounded upper surface. The vermiculate
lines on the half to the right, represent their incomplete walls.
On account of the great irregularity of the internal structure, it
is difficult to draw up satisfactorily descriptions of the species of
this genus. The same difficulty is experienced in describing the
internal construction of Strotospongia. The structure of these
sponges might, perhaps, have been better defined by saying,
that the sponges are composed of irregular reticulate fibres so
arranged that they form labyrinthically intertwined canals, or,
more or less irregular, vertical tubes.

Position and locality: Twenty-five feet above the base of the
Trenton limestone near Dixon, 111.

DYSTACTOSPONGIA RUDIS U. & E.

PL Vm, Figs. 4-4a.

Of this species also, the collection contains but one example.
This is massive, of oval shape, three and one-half inches long,
two and one-half inches wide, and one and five-eighths inches
high. It is composed of reticulate sponge fibre arranged in
such a manner that it forms very thin, cribrose leaves, .1 mm.
or more in thickness, which combine with each other at unequal
intervals, so as to produce an irregularly tubular mass. The
canals so formed vary in width from 1.5 mm. to 4 mm., and
traverse the mass in an irregular radiate manner from the
base.

•Since this was written Mr. E. O. Ulrich visited Dixon and succeeded in collecting
several other specimens of this and the following species. These agree in all respects
with the ones described.

280 PALAEONTOLOGY OF ILLINOIS.

In sections the cribrose character of the intertwining sponge
leaves is quite obvious, but the component parts of the fibres
have been so much obscured during fossilization, that they can-
not now be determined. But in the matrix which fills the canal
cavities, a large number of minute needle-shaped bodies, as well
as a few three-rayed forms, were observed.

This distinct species is separated from I), minor by the thinner
leaves, and much larger canals. From D. insolens Miller, the
type of the genus, it is distinguished by the same characters.
That species also presents a limited number of large radiate
oscula on the upper surface, which are not observable on the
species here described.

Position and locality: Twenty-five feet above the base of the
Trenton limestone, near Dixon, 111.

CAMAROCLADIA nov. gen.

Sponges consisting of small subcylindrical branching stems.
Interior with comparatively large, but short sub-cylindrical
canals, or cavities, which wind about in an irregular manner
before opening at the surface of the branches. The canals are
separated by thin cribrose walls.

The walls are now composed of crystalline calcite, and preserve
only very faint traces of the spicular fibre. In the canal cavi-
ties a number of minute, mainly isolated three-rayed forms were
observed.

This genus is proposed to include small branching fossils that
are quite numerous in the Dixon sponge layer. In their general
appearance they resemble species of Buthotrephis, a genus of the
so-called "Fucoids." Whether any of these supposed plants are
really fossil Algae remains to be seen. That many are not, will
be shown, we think, when their obscure remains are examined
and studied as they should be.

Some will probably turn out to be inorganic, others may be
trails and burrows, while not a few will prove to be sponges, as
has already been shown of Dictyophyton and Cyathophycus.

The systematic position of Camarocladia, while not positively
determined, is nevertheless, sufficiently indicated by the known
characters, to induce us to classify the genus with the calcareous
sponges, in the neighborhood of Peronella and Verticillites.

SPONGES. 281

CAMAROCLADIA DICHOTOMA U. & E.

PL VII, Figs. 1. la. Ib.

Sponge ramose, branching dichotomously at intervals of 10
mm. (more or less). Branches sub-cylindrical, 2 mm. or a little
more in diameter, with the surface smooth or minutely rough-
ened, and irregularly porous. Among the minute pores, which
we regard as interstices between the reticulate skeleton fibre,
a small number of larger ones may be detected.

Sections show that the interior of the branches is mainly
occupied by more or less confluent short sub-cylindrical cavities,
with the separating partitions very thin. The cavities seem to
wind about in an irregular manner before they open at the
surface. Their width varies but little from 0.4 mm.

The cluster of branches shown on plate VII, illustrates the
usual appearance of this peculiar sponge. The branches are
generally matted together and much broken in the rock or on
the surface of Antbaspidelhi species. In this condition the speci-
mens rarely show any recognizable structure.

There are, probably, two or three other species of this genus
in the Trenton rocks of the western states. Though very
abundant in certain layers, the conditions of preservation were
in every case so unfavorable that none of the specimens pre-
serve more than the merest traces of the sponge skeleton. Two
of them are more robust than C. dichotomy, while the third is
a smaller form and its branches divide more frequently.

Position and locality: Twenty-five feet above the base of the
Trenton limestone, near Dixon, 111.

-35

282 PALAEONTOLOGY OF ILLINOIS.

STOMATOP0110IDS.

ACTINOSTROMA? TRKNTONENSE U. & E.
PL VII. Fig. 3, 3a, 3b.

The specimen which we propose to designate as above, is a
rounded sub-hemispheric mass, 47 mm. in diameter, by 23 mm.
in height. It consists of superimposed layers, from 1 to 3 mm.
thick.

Sections are somewhat obscure, but show thai? the mass is
composed of minute irregular vertical rods, of stellate form in
cross section. At varying intervals the rods throw out from
four to six slender rays which may or may not unite with the
rays of the surrounding rods.

In its minute structure this fossil resembles the ANTHASPIDELLID.E,
but the fact that the hemispheric mass is made up of superim-
posed layers, seems to indicate a more decided affinity with the
Stromatoporoid section Actinostroma,, proposed by Dr. Nichol-
son. The typical species of Actinostroma,, one of which is illus-
trated on plate VII, differ from our species in having the rays
of the "radial pillars" placed at corresponding levels. Up to
the present time the genus wras not known to have representa-
tives in older rocks than those of the Wenlock limestone of
Britain. From that horizon two species are mentioned by Dr.
Nicholson. In Devonian deposits the species are more numerous.

Position and locality: Twenty-five feet above the base of the
Trenton limestone, near Dixon, 111.

PART II.
PALEONTOLOGY OF ILLINOIS.

SECTION VI.
PAL.EOZOIC BRYOZOA.
BY E. O. ULRICH.

BRYOZOA. 285

LETTER OF TRANSMITTAL.

To Prof. A. H. Wortben, State Geologist:

DEAR SIR: When I undertook this work it was with the in-
tention of preparing a complete monograph of the Bryozoa
found in the Palaeozoic rocks of the State. It soon became
apparent, however, that this could not be carried out, since the
class proved to be so numerously represented that neither space
nor the appropriation would suffice for the purpose. In view of
this I decided to select only the typical and most important
species and upon these to base a system of classification enabling
the student without much trouble to arrange his long neglected
material. To facilitate the study I found it necessary to write
a comprehensive introduction, containing a short bibliographic
sketch of the subject to date, an account of the general and
comparative structure of Palaeozoic Bryozoa, and a chapter on
their classification with notes upon recent methods of investiga-
tions. My classification is based almost entirely upon the
microscopic and really fundamental characters and I need not
therefore apologize if my system differs widely from those hitherto
employed. The time has arrived when some convenient and
natural arrangement for this large branch of the Palaeozoic
fauna is not only desirable but a pressing necessity if we would
use them to further the progress of stratigraphical geology.
There is no class of fossils better entitled to that distinction
than the Bryozoa, as they are more than usually persistent in
their characters. Those of the suborder TREPOSTOMATA are even
servicable where other fossils are too imperfect, since in most
cases they can be identified by means of thin sections.

286 PALAEONTOLOGY OF ILLINOIS.

The material upon which the present report is based is mostly
contained in the State Museum at Springfield. A few illustra-
tive species not in the museum were loaned for description from
private collections. Of these, whenever possible, I have placed
typical examples into the State collection, so that it may be
claimed with truth, that as a collection of Upper Palaeozoic
Bryzoa at any rate, it stands unsurpassed. The numerous thin
sections required for the work, were all personally prepared by
me. The illustrations, too, have all been drawn, and many of
them transferred to stone, by myself. On the remainder the
lithographic work was done, under my personal supervision, by
Mr. Charles Schuchert, to whom I am much indebted for the fidelity
and skill he has shown in the performance of his difficult task.

To Mr. J. M. Nickles of Sparta, Illinois, who has not only
amassed a large collection of Palaeozoic Bryozoa but also is
conversant with their structure, I am especially indebted for
much valuable assistance both by way of advice and specimens.

And to you, my dear sir, I cannot sufficiently express my
gratitude for the encouragement and many kindnesses that I
have received at your hands, nor can I forget the marked
patience and sympathy that you have shown me throughout
the progress of my work.

Very respectfully yours,

E. O. ULRICH.

BRYOZOA. 287

PREFACE

For reasons pointed out in my letter of transmittal, the pre-
sent work falls considerably short of being a "Monograph" of
the Palaeozoic Bryozoa of Illinois, and much umvrought material
still remains in the State Museum. Many new and important
forms are also contained in private collections, while in my
own there are over two hundred Palaeozoic species (many of
them from Illinois) that must await opportunities for publica-
tion. This, however, was not so much a cause for regret as the
loss of much time that was consumed in selecting just such
forms as would show the characters and limits of the genera in
the best manner. My desire to establish the generic divisions
in such a manner that they would readily appeal to the mind
of the student I sought to fulfill by incorporating into the re-
port as many diagnostic species as possible. On this account
the plates, especially the latter ones, are more crowded, and
some of the species less fully illustrated, than I had originally
intended. The crowded condition of the plates, on the other
hand, bears witness to the fact that I have done what I could
in the way of illustration, and in most cases, I have no doubt,
it will be found to suffice for present needs, or until a "Mono-
graph" of the Palaeozoic representatives of the class can be
prepared.

Palaeontologists have now universally conceded that in the
determination of such difficult groups of organisms as the fossil
Bryozoa the microscopic structure is the most essential ele-
ment. The superficial characters may vary greatly in differently
preserved specimens, or they may not be recognizable, while
the mere external form or habit of growth is too treacherous a
guide to be relied upon. The older palaeontologists, without

288 PALEONTOLOGY OF ILLINOIS.

exception, relied upon these delusive external characters in dis-
tinguishing their species, and the result is that it is now almost
impossible to identify a large number of forms which they have
described and named. Their names have become current, but
we have no assurance that we are really dealing with the forms
to which the names were originally applied. Frequently, too,
the names have been applied by subsequent observers to totally
different organisms, so that no little amount of confusion has
resulted. The ill effects of this state of things upon stratigraph-
ical geology, can scarcely be exaggerated, since it is often quite
impossible to be sure of the identification by various authors
of the characteristic fossils of particular horizons. Thus, one
often finds Chsetetes lycoperdon Say, Stenopora fihrosa Gold-
fuss, S. columnaris Geinitz, and Monticulipora or Chsetetes petro-
politanus Pander, quoted in lists as typical fossils of certain
stratigraphical horizons; but it is safe to say, that in almost
every instance there is no surety that the indentification of the
species rests upon anything beyond the worthless characters of
external form and general composition.

This confusion will continue so long as such illy characterized
and unidentifiable species are recognized by palaeontologists.

Some indulgences might be extended to early authors but I
hold that there is absolutely no excuse whatever for such work
at the present time when our facilities for giving our work
a permanent value, by doing it well, are so much better than
they were in former years. Of greater value, at present, than
the mere addition of new species to our lists, is the proper elu-
cidation of those already named.

Until within the last ten years the Palaeozoic Bryozoa did not
receive the attention from palaeontologists that they deserve,
and previous to 1875, Dr. Hiram A. Prout was the only Ameri-
can author who aimed to introduce some system into their
classification. Unfortunately, his labors were almost exclusively
confined to the Bryozoa of the Carboniferous rocks, and consist
mainly of careful delineation of species and genera. On account
of his limited acquaintance with the Silurian, Devonian and
Mesozoic forms, his conclusions were often faulty. However,
when we consider the time and the primitive methods of inves-
tigation then employed, we are forced to credit him with fine

BRYOZOA. 289

powers of discrimination and observation. To Dr. H. A. Nichol-
son the student of Palaeozoic TREPOSTOMATA is more indebted
than to any other naturalist, since to him belongs the credit of
being the first to recognize the absolute necessity of thin sec-
tions. His works mark a new departure, an epoch in the study
of these intricate fossils, and it is upon the outlined basis first
drawn by this brilliant naturalist, that my own work has been
built. We agree admirably upon fundamental principles and
the facts involved, and if we differ more or less in our conclu-
sions, I think it is mainly because Dr. Nicholson has not gone
into the comparative anatomy of the subject as deeply as I
have found it necessary to do. Nor can he have had any ade-
quate idea of the vast variety and number of the forms under
consideration.

To enhance the value of my work I have extended my inves-
tigations so as to embrace not only Palaeozoic, but also all
available Secondary, Tertiary, and recent material. The ex-
haustive works of D'Orbigny, Busk, Reuss, Manzoni, Hagenow,
Hincks and other authorities on the subject, were carefully
studied and searched for information which might throw some
light upon the early representatives of the class here treated.
Much success has attended my endeavors in this direction and
the classification now offered, though essentially the same as
the scheme published in my "American Palaeozoic Bryozoa," is
nevertheless much improved and more natural, as the whole is
based upon the microscopic and really fundamental characters
of the organisms. Nearly four thousand thin sections were
prepared, illustrating the internal characters of between six
and seven hundred species.

It is not claimed that the system adopted applies correctly in
all cases, but I am convinced that the outlines as herein drawn
will recommend themselves to all who will undertake the study
of the Palaeozoic Bryozoa with an unprejudiced mind and a firm
determination to master them. Such a student will quickly
learn that, as soon as he has accustomed himself to taking
note of every variation, and grasped the fundamental principles
of the system, the subject is less difficult than it at first seemed,
as he will find that his specimens usually drop naturally enough
—36

290 PALEONTOLOGY OF ILLINOIS.

into their proper divisions. In the chapters on general struc-
ture and classification some notes on methods of investigation
may prove of interest and, perhaps, of value.

An abridged bibliographical sketch, as well as a chapter on
comparisons between Palaeozoic and more recent Bryozoa, has
been prepared, but on account of a lack of space they could not
be printed in this volume.

TERMINOLOGY.

ZOARIUM (=polyzoarium and ccenoecium auctt.): — The compo-
site structure formed by repeated gemmation.

ZotEciuM (= cell auctt.): — The true cell or chamber in which
the polypide is lodged.

MESOPORES (= interstitial cells auctt.): — The angular or irregu-
lar cells which occupy the spaces between the zocecia in many
of the TREPOSTOMATA and some of the CRYPTOSTOMATA.

VESICULAR TISSUE: — The vesicles which occupy the space between
the zocecia in the FISTULIPORID.E and other Palaeozoic Bryozoa.

ACANTHOPORES (= spimform coralHtes Nicholson, spinifonn
tubuli Ulrich, Wandrohrchen Dybowski):— The tubular spines
which are found in so many Palaeozoic Bryozoa, notably De-
kayia, Leioclema and Rhombopora.

MEDIAN TUBULI (= Wandstrlingn Dybowski): — Very slender
tubes which are present between the zocecial walls and the
median laminae of certain double leaved forms (e. g. STICTOPO-
RID^E). Their apertures at the surface are slightly elevated and
present the appearance of series of minute granules. The small
granules in Rhombopora, Stenopora and other genera, are sup-
posed to be of the same character.

COMMUNICATION PORES:— Small pores which pass through the
walls of the zooecia and establish communication between adja-
cent cells.

O(ECIUM (= ovicell, gonocyst, goncecium auctt.):— A modified
zoGeeium set apart for reproductive functions, the inflation of

BRYOZOA. 291

the surface of the zoarium in which the embryoes are developed,
or a special receptacle which is attached to the zooecium and
serves the same purpose.

DIAPHRAGMS (=ttibul& and septa auctt.): The straight plates
which cross the tubular zocecia and mesopores in the TREPO-
STOMATA.

CYSTIPHRAGMS: — The convex plates which line the walls of the
zooecia in some of the TREPOSTOMATA.

OPERCULA or PERFORATED DIAPHRAGMS: — Horizontal plates,
perforated su been t rally, closing the mouths of the zooecia. As
growth proceeds in the colony these are left behind in the tubes
and mark the successive stages.

SUPERIOR HEMI-SEPTUM: — A plate or laminar projection which
forms the posterior border of the primitive zooecial aperture,
in the typical CRYPTOSTOMATA.

INFERIOR HEMI-SEPTUM: — A small plate often present in the
CRYPTOSTOMATA, springing from the anterior wall or the medium
laminae of double leaved forms, at a point a short distance
below the "Superior hemi-septum".

LUNARIUM: — A more or less thickened portion of the posterior
wall in mam* Bryozoa which is curved to a shorter radius and
usually projects above the plane of the zooec-ium aperture. It is
of crescentic form, and represents the "notch" which is such a
characteristic feature of the aperture of some of the recent
CHEILOSTOMATA. In the Palaeozoic Bryozoa it is variously modi-
fied and drawn out trough-like.

PRIMARY APERTURE:— "The original orifice" of the zooecium in
the CRYPTOSTOMATA.

SECONDARY or SUPERFICIAL APERTURE: — The superficial orifice
of the tubular prolongation of the original aperture.

OBVERSE and REVERSE: — Two terms employed to designate,
respectively, the celluliferous and non-celluliferous faces of the
zoaria of the FENESTELLID.E, ACAXTHOCLADIID.E, and PHYLLOPO-

RINID.E.

DISSEPIMENTS: — Short non-celluliferous bars connecting the cell-
bearing branches in the FENESTELLID.E, and developed at regu-
lar intervals. The rounded, hexagonal or quadrate meshes of
the net work thus formed are known as the "fenestrules".

292 PALEONTOLOGY OF ILLINOIS.

CHAPTER I.

GENERAL AND COMPARATIVE STRUCTURE OF PALEO-
ZOIC BRYOZOA.

To get a correct idea of the structure of Palaeozoic Bryozoa,
it is absolutely necessary that they be studied with the aid of
thin sections.

The following is a simple method for preparing sections:

The materials required are, (1) a piece of sandstone (not too
gritty) eight or ten inches wide, eighteen or twenty inches long,
and of sufficient thickness to insure solidity; (2) a piece of water
hone one inch thick, a little wider, and four or five inches long;
(3) a block of wood (walnut is the best) one inch thick, two
inches wide and four and one-half inches long. The edges of the
upper side is rounded to fit the hand, while in the lower side a
shallow excavation one and one-sixteenth inches by three and
one-eighth is made to fit the ordinary glass slip. The excava-
tion must be made so that the central portion of the glass slip
will bear upon the block, while the ends may have a little play.

With a strong pair of "wire nippers" a fragment is pinched
from the specimen of which sections are desired. This is taken
into the fingers, rubbed upon the sandstone until the surface is
perfectly flat. This is the most important part of the process,
and the greatest care must be exercised to retain (or obtain, as
the case may be,) the desired angle. This surface is now rubbed
smooth upon the hone, when the fragment is ready for mount-
ing. A drop of Canada balsam is placed upon the glass slip
and the ground face of the fragment into it. The slip is now
heated (on a heating stage or over a lamp) and the Canada
balsam allowed to boil five or six seconds, when the slip is laid
upon a horizontal piece of wood to cool. After it is cold the

BRYOZOA. 293

balsam should be tested, and, if it is not hard and brittle, must
be reheated. If of the proper hardness, the block is moistened,
the slip placed into the excavation, and the superfluous material
rubbed away upon the sandstone. When nearly thin enough it
is taken out of the block and finished upon the hone. After
thoroughly cleaning and drying the section may be covered
with a thin sheet of glass, or only a film of balsam, when it is
again heated and the air bubbles, if any are present, expelled
by faint pressure upon the section with some pointed instru-
ment.

Of course it requires a certain amount of experience and time
to make good sections, yet even the beginner ought soon to be
able to make from twenty to thirty sections daily, while an
expert may increase the number to forty and even fifty.

For reasons which will become apparent to the reader further
along, these sections must be prepared with a knowledge of
certain peculiarities which are common to the Bryozoa, other-
wise the sections will be misleading. Take for example any
ramose or palmate form, and the student will find that the
zoarium of such Bryozoa is composed primarily of two distinct
zones, an inner or axial region where the zooecia are tubular,
with very thin walls, and more or less nearly vertical, and an
outer or peripheral region composed of the same tubes bent
outwards at varying angles in order to reach the surface. In
this outer region the zooecia are supposed to have entered the
mature condition, and it is here only that such accessory
features as the acanthopores and mesopores are developed. The
necessity of two sections, a vertical and a transverse, is at once
obvious, but as neither of these sections will give us a cross
section of the zooecia in their peripheral region, where the adult
and consequently the most important characters are to be
found, it is evident that a third section must be prepared,
which will enable us to investigate these characters. This sec-
tion, which is called ; 'tangential," must divide the zoarium along
a plane paralled with the surface, and only a little below it. Of
bifoliate forms two tangential sections ought to be made, one
passing through the zoarium just below the surface, and the
other just above the median lamina. In thin examples of this

294 PALEONTOLOGY OF ILLINOIS.

style of growth one large section can be made to show the
characters of the zocecia from their origin to the aperture.

For massive, parasitic, or discoid zoaria, two sections (verti-
cal and transverse) will ordinarily suffice to bring out the
principal characters, but it is advised that two or more trans-
verse sections be prepared, dividing the zoarium at different
heights.

I. Mode of growth. — In considering the general structure of
fossil Bryozoa, the mode of growth and the form ultimately as-
sumed by the zoarium, though generally of but sub-ordinate classi-
ficatory value, may very appropriately be mentioned first. The
out ward form of the zoarium, though extremely variable, when the
whole class is taken into consideration, is tolerably constant for
each species, and not infrequently all or most of the species belong-
ing to one genus may adhere more or less strictly to some particu-
lar method of growth. The importance of variation in outer
form as a factor in classification is very much diminished by
the fact that many species may vary considerably in shape, and
but very slightly in their minute structural characters, while on
the other hand structurally diverse species may assume the
same outward form. We must admit, however, that in many
Bryozoa the ultimate form of the zoarium is largely determined
by the shape and reproduction of the zooficia, and in these the
external form is of the first importance, since it is indicative of
variations in structural characters.

The zoaria of Palaeozoic Bryozoa usually exhibit one or the
other of the following conditions:

1. The incrusting or parasitic zoa.rium, in which the colony
is parasitically attached by the whole of the lower surface to
foreign bodies, such as shells corals other Bryozoa or stones.
The zooecia are short, usually tubular, and by the formation of
successive layers the zoaria may form large masses. Examples
are several species of Leptotrypa, Spatiopora, Palseschara,
Atactopora, Ceramoporella, Eridopora, Stomatopora, etc.

2. The laminar zoarium, differs from the encrusting only in
being free and in having the lower surface covered with a
wrinkled or striated epithecal membrane. The colony usually
commences its growth upon some small object. This type of

BRYOZOA. 295

growth is represented by many species of Fistulipora, Monticuli-
pora cincinnatiensis Nicholson, and several species of Steno-
pora.

3. The massive zoarium, which may be free, attached only at
the base, or growing around some foreign body. The zooecia
form long tubes, divided at more or less frequent intervals by
diaphragms. The massive zoarium is seen in Monticulipora
mammulata D'Orbigny, some species of Leptotrypa, Mono-
trypa, Fistulipora and Crepipora.

4. The discoid zoarium has the form of a plano-convex or
concavo-convex disc. Generally the convex surface is cellulifer-
ous and the flat or concave surface covered Avith a striated and
wrinkled epitheca. Monotrypa? petasiformis Nicholson, Lepto-
trypa discoidea Nich., Diplotrypa petropolitana Pander, and
Prasopora lycoperdou are examples. More rarely the upper or
celluliferous surface is concave or flat, and the lower side con-
vex. Of this condition Scenellopora radiata, and Proutella dis-
coidea (Prout sp.) examples. The same type of zoarium per-
tains to species of Aspidopora, Discotrypa and Cyclopora, but
in these the height when compared with the width is propor-
tionately much less than in the examples first cited. In all,
the adult form was essentially free, but that the majority were
originally attached to some small foreign body usually admits
of demonstration.

5. The bifoliate zoarium, in which the zooecia diverge from a
double median lamina or basal plate, and open upon the two
surfaces of a foliate expansion, or of flattened branches. This
type of growrth is very common, being characteristic of the
PTILODICTYOXID.E and STICTOPORID.E. Among the CYSTODICTYO-
NID.E, Prismopora, Glyptopora and Evactinopora offer peculiar
modifications of this type of growth.

6. The dendroid or ramose zoarium, in which the entire free
surface is covered by the apertures of zooecial tubes, is very
common among the TREPOSTOMATA. The tubes radiate in all
directions from an imaginary axis, or from an axial tube. A
ramose zoarium is seen in Rhombopora, Batostomella, Am-
plexopora, Monotrypella, Diamesopora, Nematopora, etc., etc.

296 PALEONTOLOGY OF ILLINOIS.

7. The frondescent or palmate zoarium is intimately con-
nected with the ramose, the arrangement of the zocecia being
the same. It usually consists of leaf-like expansions with the
edges rounded and celluliferous. Good examples are Heterotrypa
frondosa D'Orbigny, sp., and Homotrypa dawsoni Nicholson.

8. The segmented zoarium is characteristic of a number of
Palaeozoic Bryozoa. In these the complete zoarium is com-
posed of more or less numerous, simple or branched segments,
with each end slightly bulbous and subsolid. This type of
growth is seen in ArthrostyJus, Arthropora, Arthroclema, Dicra-
nopora and Helopora, all Silurian genera. It has also been
observed in a new form from the Hamilton group of New York.

The species of Ptilodictya may also be included with the seg-
mented Bryozoa, since the basal extremity of the zoarium in
this genus is pointed and was inserted in the socket-like depres-
sion of an attached basal expansion.

9. The fenestrated zoarium, in which the colony is composed
of slender branches, celluliferous on one side, which anastomose
with each other as in Phyllopora and Phylloporina, or are
united at regular intervals by non-poriferous processes (dis-
sepiments) the whole forming a flabellate, spiral or infundibular
expansion. Fenestella, Polypora and Semicoscinium are ex-
amples.

Archimedes and Lyropora are modifications of this type of
growth. In the first there is a solid spiral axis; in the second
two strong diverging supports, between which the reticulate ex-
pansion is spread.

10. The pinnate zoarium differs from the preceding in being
composed of a straight central branch and more slender lateral
branches, which spring from the sides of the main stem. Acan-
thocladia and Pinnatopora.

11. Surface characters. — Aside from the superficial characters
of the zocecia, which will be treated in another place, the sur-
face of a large number of Palaeozoic Bryozoa presents certain
peculiarities, which, on account of their conspicuousness, demand
special consideration. Foremost among these are the structures
commonly known as "monticules" and "maculae" which, though
properly enough applied to designate distinct conditions, are

BRYOZOA. 297

morphologically the same. In a strict sense the "monticules"
are circumscribed areas on the surface of the zoarium which are
elevated to a variable degree above the general level and con-
stitute a more or less regularly distributed series of conical
rounded or elongated eminences. Usually the "monticules"
are occupied by zooecia more or less decidedly larger than those
of the average size in the intervening spaces, though in some
cases the difference in this respect is quite inappreciable. Ap-
parently always, however, the cells on the monticules are dis-
tinguished by some peculiarity, so that if they are not larger
they may be recognized by their thicker walls, or by the greater
width of the spaces between them. Monticules having the struc-
ture here described are present in Afonticulipora mammulata
D'Orb., M. cincinnatiensis Nicholson, Callopora ramosa D'Orb.,
Monotrypa? filiosa D'Orb., Discotrypa elegans, Spatiopora
montifera and Homotrypa dawsoni Nicholson.

The "maculae" like the "monticules" are circumscribed spaces
on the surface of the zoarium, but differ from them in being
composed of aggregations of mesopores or vesicular tissue, in-
stead of groups of large zooecia. It is a fact, however, that
the zooecia which surround the "maculae" are almost invaria-
bly appreciably larger than those farther removed from the
centre of a "macula." The surface of the maculae may
be finely porous (e. g. Heterotrypa subpulchella NicholsoD,
Crepipora impressa), with the mesopores visible but closed
(e. g. Dekayella obscura and Peronopora decipiens Rom-
inger). apparently solid and elevated above the general
level of the surface (e. g. Atactopora maculata, Crepipora
solida), or smooth and depressed. The last condition is the
most typical and common, and is represented in a more or less
marked manner by all of the FISTULIPORIDJ;, and many of the
CYSTODICTYONID.E. In these families the interspaces between the
zooecia are occupied by lenticular vescicles which, at any rate
in the perfect adult state, are not visible at the surface. The
'•maculae" are depressed, often stellate and quite regularly
arranged, when they impart a very characteristic and orna-
mental appearance to the zoarium. Though of rare occurrence,
"maculae" are also occasionally present among the STICTOPO-
(e. g. Pachvdictya and Phyllodictya) , but the non-porifer-
-37

298 PALEONTOLOGY OF ILLINOIS.

ous margin, which is so characteristic a feature of the zoarium
of that family as well as of the PTILODICTYONID^ and CYSTO-
DICTYONIDJE, is essentially the same thing, since its minute structure
is precisely similar to that of the maculae. The non-poriferous
margin further agrees with the "maculae" in the fact that the
zocecia which are nearest to the margin are almost invariably
larger than those occupying the central region of the stipe. In
Prismopora serrata Meek, and P. trifolia Rominger, the mor-
phological identity of the non-poriferous margin and the "mac-
ulae" is clearly shown, the two being confluent.

As regards the uses of the "monticules" and "maculae," the
only suggestion that seems at all applicable, is that they had
something to do with the reproductive functions. The large
cells which occupy the monticules or surround the maculae must
in that case have been the receptacles in which the embryo were
developed into the larval stage. This explanation is made very
plausible by a comparison with the goncecium of Crisia, which
is nothing more than a slightly modified zooecium set apart
for reproductive functions. The ocecium of many other Cyclo-
stomatous Bryozoa is simply an inflated Zooecium, which also
may be slightly modified in other respects. In Strotopora, a
new genus of the FISTULIPORID^E, the surface exhibits more or
less numerous cells which are curiously modified in having the
apertures abruptly expanded to two or three times the normal
width. In the perfect state the aperture is arched over and
presents the appearance of a small vesicle. That these struc-
tures represent ooecia will scarcely admit of doubt.

III. Mesopores and vesicular tissue. — The term "Mesopores"
was proposed by Nicholson and Foord for the cells which oc-
cupy the spaces between the true Zooecia previously known as
interstitial cells and cancelli.* They applied the term equally
to the interstitial tubes of CaUopora, Prasopora, Diplotrypa,
Eeterotrypa, etc., and to the vesicular cells of Fistulipora. These
structures are, however, very distinct and ought to be known
by different names. I propose, therefore, that the use of the
term "mesopores" be restricted to the tubular interstitial cells,

* Prof. Busk and other authors applied the name "cancelli" to the interstitial tubes
ol Heteropora and other Bryozoa of that type. Mesopores is supposed to be a more
appropriate term, and is used by me in its stead.

BRYOZOA. 299

and that the lenticular vesicles provisionally retain the more
appropriate designation "vesicular tissue."

In this restricted sense the mesopores are tubular cells occu-
pying the interspaces between the true zooecia. Their number
and size varies greatly in different species, being quite variable
even in species of the same genus. In some they are very small
and occur only at the angles of junction between the zooecia,
while in other forms the latter are completely separated from
each other by one or more series. When closely examined they
are found to be, perhaps in all cases, more or less decidedly
angular and of irregular shape, though it is not infrequently
found that the angles are blunted and the cavity rounded by
an internal deposit of sclerenchyma. This is the case in all
those forms in which the cell walls are thick. Numerous ex-
amples might be cited, but Stictoporella and Batostomella will
suffice. In longitudinal sections the tubes of the mesopores are
generally distinguished from the true zooecia by their compara-
tively more numerous diaphragms, which are always horizontal
and "complete.'' From a morphological point of view the most
important character of the mesopores is found in the fact that
they do not occur in the axial region of the zoarium, but first
make their appearance in the cortical portion after the original
zooecia have commenced to bend outward (or upward as the
case may be) in their course to the surface.

The structure known as "vesicular tissue" is composed of
lenticular cells, which fill the interspaces between the zooecia in
the FISTULLIPORID.E and CYSTODICTYONIDJS. Unlike the mesopores
they originate already in the axial region, being, howrever, more
numerous as well as smaller in the superficial portion of the
zoarium. They are never arranged so as to form tabulated
tubes like the mesopores, but occur in horizontal layers, the
constituent cells of which are quite independent of those of the
preceding layer. Near the surface of an adult zoarium they are
largely filled with sclerenchyma, which more or less completely
obliterates their individuality. This deposit, however, is
traversed by minute vertical tubuli, that seem to serve the pur-
pose of maintaining communication between the open cells and
the surface to which their prominent terminations impart a
minutely granular aspect. Vesicular tissue is also developed in
the older regions of species of Semicoscinium between the "ca-

300 PALAEONTOLOGY OF ILLINOIS.

rinse," and especially in the footstalk. The discovery of that
structure in such unequivocal Bryozoa as the FENESTELLHXE is
of the greatest importance in its bearing upon the question of
the zoological position of the FISTULIPORULE. In the proper
place we will consider it in greater detail.

IV. Acanthopores. — A large number of Palaeozoic Bryozoa,
especially among the TREPOSTOMATA, present, when in a good
state of preservation, a greater or less number of blunt spine-
like structures, which are placed around the zocecia apertures,
usually at the angles of junction between adjoining cells Some-
times they also occur at some point between the angles, while
in other forms, notably such as Leioclema species, in which the
mesopores are very numerous, they are apparently included
within the substance of the walls of the zocecia. These peculiar
appendages present themselves at the surface as so many blunt
projections, varying considerably in prominence and size in
different species, In the genus Dekayia, they attain a greater
size than in any other, being in some species almost or quite
as large as an average zooecium. Ordinarily they are much
smaller than this, while in some forms they are so much re-
duced in size that it is difficult to distinguish them from the
elevated surface terminations of the "median tubuli" (e. g.
Rhombopora species, and Leioclema? araneum). Thin sections
show conclusively that they were all originally hollow, and the
apical aperture of the spines may in rare instance be detected.
Generally, however, the summit of the spines appears to be solid,
but this fact may be easily accounted for by the readiness with
which the excessively minute apertures would be filled up by the
matrix or by infiltrated calcite. As stated, sections prove beyond
a doubt that we are not dealing with mere superficial ornaments,
but that they extend into the substance of the peripheral region
of the zoarium, in which they can be traced to a depth equal
to that reached by the "mesopores". As seen in tangential
sections they appear as circular spots of somewhat darker or
lighter shade than the wall substance immediately surrounding
them.

301

Fig. I. Leioclema foliatum, UL Warsaw beds, Warsaw, DL— a, Vertical section x28.
showing entire thickness of zoarium, tabulation of zocecia and mesopores, and struc-
ture of the aeanthopores : b, tangential section x28, showing distribution of acanthopores,
mesopores and zooecia; c, small portion of wall x50: d, acanthopore x50, showing its
structure.

Further examination shows that they are composed of lami-
nated sclerenchyma, disposed in a concentric manner around a
circular clear or dark central space. In vertical sections the
minute central canal is often clearly seen, as well as the struc-
ture of the thick walls. The concentrically laminated structure
noticed in tangential sections proves to be produced by a succes-
sion of overlapping conical layers of sclerenchyma. This arrange-
ment of the laminae proves conclusively that the aperture of the
spines was at all times approximately of the same diameter,
and completely overthrows the supposition advanced by Dr.
Nicholson (''The Genus Monticulipora", p. 47), that these
spines were a peculiar form of corallites, the mouths of which
became closed by secondary deposit as the corallum assumed its
final characters. On the same page he also says: ''It is not, of
course, essential that we should suppose these singular struc-
tures to be occupied by polyps; but I think them to be modified
zooids in the same sense as is true of the 'avicularia' of the
Polyzoa''. I am perfectly willing to accept Dr. Nicholson's
view as it is expressed in the above quotation, since I am fully
convinced that in the "acanthopores" we are dealing with
structures that supported appendages most likely of identical
nature and functions with the avicularia or vibracula found on
recent Bryozoa. This explanation possibly applies only to the
large acanthopores as they are seen in Dekayia,, species of
Leioclema. and other forms. The smaller and closely arranged

302 PALAEONTOLOGY OF ILLINOIS.

ones, characterizing the genera Batostomella, Amplexopora,
Atactopora and Rhombopora, were most probably occupied by
somewhat different yet homologous appendages. These may
find an explanation in the stout, chitinous or calcareous bristles
which are found upon the walls of the zooecia in many CHEILO-
STOMATA. After the death of the zooid these bristles fall off,
leaving minute pits in the summits of small blunt spines.

True acanthopores are also present in a large proportion of
the FENESTELLID^E and ACANTHOCLADIID^E. In Fenestella, Ptylo-
pora and Septopora, the mesial carina very often bears strong
spines, which sections prove to have been hollow and con-
structed upon the same general plan as the "acanthopores" of
the TREPOSTOMATA.

In Polypora and other genera having more than two rows of
zooecia they are distributed among the cells jWith greater or
less regularity.

The apical apertures are not often preserved, but they are
shown in a beautiful manner in specimens of several species de-
scribed in this volume (Fenestella wortheni, PI. 52, fig. 5, 5a,
and Ptylopora cylindracea, PI. 66, fig. 2). While I regard these
"acanthopores" as probably having been occupied by vibracular
structures, some other explanation seems necessary to account
for the peculiar "dimorphic pores" occurring so abundantly upon
the non-poriferous side of the branches in Septopora, Acantho-
cladia fruticosa and Semicoscinium infraporosum. These pores
are also present on the celluliferous side of several species, where
they are scattered among the zooecia. In the species last men-
tioned, we find them on each side of the prominent mesial keel.
These cannot have contained the same kind of modified zooid
as the acanthopores, since they are generally much larger than
the latter, and because in most cases (notably Septopora
biserialis Swallow) both kinds of pores occur in the same
species. If in the "acanthopores" we see the supports of vibracu-
lar structures, would it be unreasonable to suppose that the
"dimorphic pores" were the receptacles of "avicularia"? I see
nothing in their structure to negative the supposition, nor
would these be the only instances in which both avicularia and
vibracula occur together, as, according to Hincks, both kinds
of appendanges are present in two genera of the CHEILOSTOMATA.

BRYOZOA. 303

We now pass on to the consideration of other sets of minute
tubuli, which, though often strongly resembling the "acantho-
pores'', must have had very different functions. Until they are
better understood I propose to designate them by the term
''median tubuli", the name having reference to their position in
the zoarium.

V. Median tubuli. — In its strictest sense the term applies to
certain exceedingly slender longitudinal tubes which are present
between the two median laminae in many of the STICTOPORID.E.
In Stictopora and P achy diet y a they are of sufficient size to be
recognized with ease in transverse sections. So far as observed
here, they do not seem to be provided with distinct walls, but
appear to have been produced by an equal longitudinal grooving
of the laminae, so that half of the tube is on each side of the
divisional line between the laminae. Another set, which I con-
sider as essentially of the same nature as those just described,
traverses the walls of the zooecia (or the interspaces between
them) in a vertical direction. These are arranged in crowded
series and very much resemble small "acanthopores''. In Sticto-
pora and some species of Pachydictya they are usually arranged
in a single series along the middle of the walls between the
zooecia. In certain species of Stenopora, Rhombopora and
Anisotrypa they are also arranged in a single series, but in
these they are confined to a distinct linear space which sepa-
rated the walls of adjoining zooecia. Structures of probably the
same type, but slightly modified, occur in the walls of Idiotrypa
parasitica and Nicholsonella ponderosa.

The spine-like structures of Fistulipora utricula Rominger, F.
spinulifera Rominger. and other species of the genus, which
Nicholson and Foord identified with the "acanthopores" of
Dekayia, are, most probably, of a veiy different nature. That
in tangential sections they resemble small acanthopores is true,
yet certain peculiarities, which they often show in an unmis-
takable manner, indicate functions decidedly different from those
here attributed to the true acanthopores. On plates 4(5 and 48
I have figured sections of various species of Fistulipora, some
of which are provided with the structures in question. Upon
close examination we find that the cover of the interstitial vesi-
cles is perforated by one or more minute openings that look

304

PALEONTOLOGY OF ILLINOIS.

Fig. 2. — a, Transverse section x50 of Ptilodictyavariabilis,* showing the basal portion
of the two layers of zocecia, and the duplex character of the median lamina; between
the plates there is no series of median tubuli.— b, small portion of a tangential section
of Tceniodictya cingulata, x 50, showing a transverse lining of the central region of the
walls, a character often present among the PTILODICTYONID^;.— c, deep tangential section
of Stictopora mutabilis, VI., x 50, showing the primitive portion of the zooscia and the
median tubuli in their walls.— d, tangential section of same showing characters of zooecia
just beneath the superficial aperture.— e, transverse section of a young example of same,
x 50, showing median tubuli.— f, transverse section of old example of same, x 50.— g, Ver-
tical section through one zooecium of an old example of same, x 50.— h, vertical section
section of a young specimen of same, x 50.

"This name is proposed instead of Ptilodictya nodosa for the form figured in my
"Amer. Pal. Bryozoa," under that name, Hall's Escharopora nodosa (Pal. N. Y. vol. 1,
1847.) having proved to belong to Ptilodictya,

BRYOZOA. 305

just like the supposed acanthopores; and, when the section
passes through the zoarium just beneath the surface of a fully
matured example, where the vesicles are filled with a dense
deposit of sclerenchyma, they cannot be distinguished from each
other. Precisely the same conditions prevail in Coscinium,
Eractinopora, Phyllodictya, Pachydictya. Idiotrypa, Nichol-
sonella and Constellaria, and, with the addition of true acantho-
pores, in species of Trematopora. On account of their excessive
minuteness and consequent liability to obliteration, I have found
it extremely difficult, if not impossible, to determine whether these
structures are ever actually tubular (i. e., like the acanthopores,
passing in a continuous line through successive stages of the
zoarium). The evidence afforded by vertical sections is generally
opposed to this view, excepting in some sections of Cystodictya,
and other genera, in which the secondary deposit that filled the
interstitial vesicles exhibits a finely lined appearance, making it
not unlikely that calcification was arrested by the pores and
only extended around them, so that with the continuation of
the deposit, they gradually formed tubular shafts*. Taking all
the evidence at hand into consideration, the only plausible ex-
planation would seem to be that we are dealing with small per-
forations in the calcareous covers of the mesopores and inter-
stitial vesicles. Whether these were closed at the termination
of each stage, or remained open so as to maintain communica-
tion throughout the zoarium, is a problem we may never be
able to solve.

In species of Ptilodictya of the type of P. pavonia D'Orb.,
and P. falciformis Nicholson, and Tseniodictya, (n. gen.) and
Cyclopora fungia Prout, the intra-mural space is crossed by
numerous dark lines, which tangential sections, taken from ex-
ceptionally preserved specimens, show to be composed of closely
arranged spots. Whether these spots represent extremely min-
ute vertical tubes or moniliform tubuli, which traversed the

*In the Ann. & Mag. Nat Hist. 5 ser. vol. 13, p. 213, Rev. T. Hincks, the eminent
authority on recent Bryozoa, describes a very similar condition in the development of
his Mitcronella spinosissima var. major. After stating that in the young state there are
two or three rows of pores around the margin of the zocecia, he says, "As calcification
proceeds it is arrested by the pores and only extends around them and not over them;
so that they continue open and form at last tubular shafts piercing the stony cru.s
which has been piled up about them,"

--38

306 PALEONTOLOGY OF ILLINOIS.

walls in a transverse direction, is a point not yet determined.
The evidence at hand favors the last possibility more than the
first

Sections oiRhomboporalepidodendroides, E. crassa, Bactropoi-a,
simplex, Stenopora? signata and several other species, exhibit a
most peculiar character, which is perhaps best shown in the
species last mentioned. In tangential sections of these forms,
the portion af the wall immediately surrounding the zocecial
cavity displays one or two series of minute spots with a dark
or lucid central space, while each ''acanthopore" is likewise en-
circled by a row of the same spots, which again in the central
region of the walls are arranged is closely approximating clus-
ters of six or more. As viewed in vertical sections, they still
present only the appearance of minute spots, and I have not
observed anything showing that they communicated either with
each other or the zooecia, nor can I offer any explanation of
the singular structures-

In a large proportion (perhaps all) of the FENESTELLID/E the
non-poriferous side of the branches as well as the spaces between
the zooecia apertures are pierced (?) by very minute vertical
tubes, which compare with the surface pores of both the CYCLOS-
TOMATA and CHEILOSTOMATA.

VI. Structure of the walls of the zocecia. — From a zoological
point of view the minute structure of the cell walls is of the
first importance. Unfortunately, however, the process of fossili-
zation has so often obliterated the finer details, that great
caution and careful examination are necessary if we would
obtain a correct idea of their structure. Still, with the aid of
good sections the differentiations are determinable and may be
utilized with great advantage in the framing of our classifica-
tion. Before we proceed to discuss the more common modifica-
tions in the minute structure of the zooecial walls, it is necessary
to notice a very important feature of zoarial anatomy.

a. "Mature" and ''immature7' regions. In the TREPOSTO-
MATA and CRYPTOSTOMATA, namely, the tubular zooecia which
make up the zoarium become more or less modified in their
structure as they approach the surface and pass into their final
stage of growth. In all cases, whatever their structure may be

BRYOZOA. 307

in the final and most developed condition, they commence with
thin and apparently indivisible walls. This I have called the
"immature" portion of the tubes; in the ramose, frondescent,
and bifoliate forms, it occupies the axial and deeper regions of
the zoarium The peripheral or what I have termed the "ma-
ture" region commences near the point at which the tubes bend
outward and from there extends to the surface. Generally, the
two regions differ widely from each other. Thus in the "im-
mature" region the tube walls are exceedingly thin and the dia-
phragms, if not entirely absent, are always separated by longer
intervals than in the "mature" region, while none of the accessory
elements, such as the inesopores and acanthopores, are developed
until the zootria have passed out of this region. On the other
hand, in the "mature" region the walls of the zooecia become
more or less extensively thickened, and if at all present, such
structures as the cystiphragms and perforated diaphragms, meso-
pores and acanthopores are developed. As already mentioned, the
diaphragms are also comparatively more numerous and, as I
will endeavor to show in the section on diaphragms and oper-
cular structures, in some forms at any rate appear to be of a
different nature from those which cross the tubes in the "im-
mature" region. The thickening of the walls of the tubes by a
secondary deposit and a general increase in the deposition of
calcareous material is one of the most conspicuous features of
the "mature"' region.

The thin walled basal or prostrate portion of the zooecia of
the bifoliate, encrusting and fenestrate species, is equivalent to
the "immature" region of the dendroid forms, while the erect por-
tion represents the "mature" region. Among massive forms the
two regions are often readily distinguished. This is especially so
when the zoarium is composed of numerous layers as in Stenopora
polymorphfi Prout. In cases of this kind each layer is divisible
into a prostrate or immature and an erect or mature region.
Less easy is the task with species like Monotrypa? filiosa D'Orb.,
and Monticulipora mammulatti D'Orb., in which the layers are
so intimatelv connected that the tubes form continuous lines

v

through the mass. Yet even in these, the two zones are distin-
guishable, the walls being slightly thicker and the diaphragms
more closely arranged in the "mature" region than in the im-

308

PALEONTOLOGY OF ILLINOIS.

mature. I have seen specimens of these species in which it was
possible to distinguish more than twenty successive zones, with
out a break in the continuity of the tubes. A separation of
the zoarium into different zones is apparently not possible with
the true species of Monotrypa (e. g. M. undulata Nich., M. rec-
timuralis). In these extremely simple forms the walls of the
tubes remain excessively thin throughout their length, the dia-
phragms are separated by wide and unequal intervals, and
neither mesopores nor acanthopores are present.

b. Independence of the Zocecia walls. — Theoretically it may
be said that the zocecia of all the Palaeozoic Brj'ozoa had per-
fectly independent and complete walls. In many cases this in-
dependence of the wall of each individual cell or tube is clearly
preserved throughout the entire growth of the zoarium and in

Fig. 3. Tangential sections of Palaeozoic Bryozoa showing variations in wall struc-
ture, x50. a. Monotrypa rectimuralis Ul., showing the extreme simplicity that marks
that genus. 6. Monotrypella cequalis Ul., showing structure of walls just beneath the sur-
face, c, a similar section of Amplexopora cingulata UL, showing slightly more complex
structure, d, similar section of Callopora subnodosa UL, showing apparent amalgama-
tion of walls, e, Arthropora shafferi Meek, /, Heliotrypa bifolia UL, showing the most
complicated structure yet seen.

BRYOZOA.

309

thin sections of such forms, of which Monotrypella pulchella Ed.
& H.. Amplexopora cingulata, Anisotrypa symmetrica, Steno-
pora carbonaria "Worthen, Ptilodictya pavonia D'Orb., Nema-
topora lineata Billings, Pachydictya everetti, Batostoma varia-
bile and many others are examples, the visceral chambers of
each zooecium is seen to be surrounded by its own calcareous
investment, and to be separated from its immediate neighbors
by a more or less clearly marked dark or light line. The
actual thickness of the walls inside of the divisional line varies
with the species, but in a comparatively small number of forms,
represented by the species like Monotrypa rectimuralis, Diplo-
trypa petropolitana Pander, and D. patella, they are so thin
that their duplex character cannot be made out in thin sections,
appearing in them merely as delicate dark lines. However, as
Nicholson truly says, "rough fractures will demonstrate what
thin sections fail to show.'' In rough fractures of the zoaria of
these species the tubes always separate clearly from one another,
each carrying with it its own wall, a phenomenon which could
not be possible if the primitively duplex condition of the walls
of adjoining tubes had in reality been destroyed.

In another group of forms comprising mainly thick walled
species, and, with others, the species of Batostomella, Leioclema,
Atactopora, many of Rhombopora and several of Stenopora,
there is no distinct divisional line in the centre of the partition
between contiguous tubes and the walls appear to be actually

Fig. 4. Vertical sections x50, showing variations in wall structure, a, Monotrypella
cequalis UL; 6, Stenopora americana UL: c, Amplexopora cingulata Ul.; d, Monotrypa
rectimuralis UL

310 PALEONTOLOGY OF ILLINOIS.

amalgamated. That there is no real fusion of the walls in
these cases is shown by abundant and conclusive evidence, fur-
nished, however, only by exceptionally preserved material. Or-
dinarily the visceral cavity is surrounded by concentrically
laminated sclerenchyma, while the central portion of the parti-
tion seems absolutely structureless. After a careful examination
of numerous sections, I find that this condition of parts is
mainly due to two causes, (1) imperfect preservation, (2) to
slight irregularities in the deposition of the internal laminae of
the sclerenchyma. The first cause needs no explanation, as
better specimens will show the median line in the wall which we
know to be double. The second occurs only in forms having
the partition rounded at the surface (e. g. Stenopora carbon-
aria, Worthen) and never in those in which they are carinate
(e. g. Anisotrypa symmetrica). When observed in longitudinal
sections, the partitions between the zooecia are seen to be com-
posed of a succession of superimposed conical layers, which are
deposited one upon the other as the growing margin of the
wall is carried upwards. When the centre of the partition is
carinate at the surface, then a more or less distinct straight
line passes through the apices of the conical laminae, but in
those forms that have the superficial termination of the par-
titions rounded, the separating line or primitive wall is often
made slightly zigzag by the alternate overlapping of the de-
posit on each side. This peculiarity sufficiently explains the
fact that while the divisional line may be quite distinct at one
point of a tangential section, it is scarcely or not at all per-
ceptible in other portions of the section. In considering the
wall structure of Bryozoa with numerous "mesopores," like
Callopora, Trematopora, Constellaria and Leioclema, we find
no difficulty in demonstrating the independence of the walls of
each zooecium, since, even when in contact with each other, a
divisional line is generally traceable. To show the duplex
character of the partitions between the mesopores, is a far
more difficult task, yet, that they are really double, will scarcely
admit of question. Like the thin-walled tubes of Monotrypa
and Diplotrypa, as well as the extremely thin partitions of the
tubes in the axial or immature region of nearly all the Palaeo-
zoic Bryozoa, the double condition of the mesopore walls is
conclusively shown by the fact that fractured surfaces almost

BRYOZOA. 311

invariably exhibit the exterior of the tubes. On the contrary,
rough fractures of Bryozoa with interstitial vesicles like Fistu-
lipora, Cystodictra, etc., expose the interior of the cells. I am,
therefore, not inclined to regard these as each having its own
complete investment. The only portion of the confining invest-
ment which can be said to be strictly its own, is the convex
plate which forms its upper boundary*

If actual fusion of the walls of contiguous zooecia ever oc-
curs among Palaeozoic Bryozoa, it is to be looked for in the
CERAMOPORID.E. This family is distinguished by a wall struc-
ture differing obviously from that observed in such Bryozoa as
Leptotrypa, Stenopora, Rhombopora, Amplexopora or Bato-
stomella. In the CERAMOPORIDJE, namely, the walls of adjoining
zooecia and mesopores seem to be perfectly amalgamated, and,
so far as observed, rough fractures always exhibit the interior
of the tubes. In species with thick walls (Diamesopora coin-
munis) the central portion of the partitions, as seen in tan-
gential sections, is sometimes apparently structureless, but gen-
erally a more careful examination will reveal a peculiar granu-
lar or intermittent appearance, while in species with thin walls
(e. g. Crepipora simulans and C. hemispb&i-ica,) the whole wall
is of this composition. Very nearly the same granular wall-
structure is observed in species of Monticulipora, but in these
the duplex character of the partitions is demonstrated by rough
fractures. In all these cases the appearance here described as
granular or intermittent, is most probably due to the imperfect
preservation of excessively minute pores in the walls of the
tubes. Being a feature of some importance, it will be referred
to again.

The most obvious peculiarity of the Ceramoporoid wall is
found in the irregularly laminated deposit immediately sur-
rounding the tube cavity. The lines which separate the con-
centric lamina* rarely extend around the wall, and in most in-
stances are not parallel. Sometimes they even appear to inter-
twine. When examined in vertical sections the walls present
the appearance of being composed of narrow, super-imposed,
alternately light and darker bands of sclerenchyma, which slope
backward and downward. A narrow structureless and often
nearly colorless band which hues the inner side of the posterior

312 PALEONTOLOGY OF ILLINOIS.

wall, represents the lunarium, which (among the CERAMOPORID.E)
is usually distinguished from the rest of the zooecial investment
by its lighter color.

The primitive duplex character of the zocecia walls of the
FENESTELLHLE and ACANTHOCLADIID^ is generally shown in deep
tangential sections, but, after they have passed into the erect
stage, the divisional lines are rapidly obliterated by the deposit
of layers of calcareous material in the spaces between the aper-
tures. As is seen in transverse and vertical sections, these
layers are deposited equally over all portions of the original
zooecia, appearing as parallel bands, conforming with the shape
of the primitive zoarium. Among the bifoliate genera of the
CRYPTOSTOMATA, Stictotrypa is built up upon very nearly the
same plan. Here, also, the originally thin cover of the zooecium
is thickened by the deposition of successive horizontal or con-
cave layers of sclerenchyma. Vertical sections of this genus,
therefore, are very different from those of Stictopora and Ptilo-
dictya, in which the walls are constructed upon the same plan
as in Rhombopora, etc.

Lastly, the walls of the CYCLOSTOMATA genera Stomatopora,
Protocrisina, Miioclema, etc., have that finely granular appear-
ance in thin sections, which I consider as indicative of an
originally porous condition of the wall. That the walls were
really pierced by fine pores is clearly shown by numerous speci-
mens from Cincinnati, O., and elsewhere. So far as the inde-
pendence of the walls of contiguous zooecia is concerned, the
sections studied offer no positive evidence.

c. Connecting foramina or communication pores. — While evi-
dence showing that the zooids of a colony communicated freely
with each other is abundant, it is nevertheless true that it is
rarely or never so conclusive with Palaezoic Bryozoa as to de-
termine this point beyond dispute. Only now and then a speci-
men is found furnishing any evidence whatever to bear upon
the question, and in the great majority of cases the observer
is left in total ignorance upon this important point of bryozoan
anatomy. Of the most typical CYCLOSTOMATA, some of which
were represented in Palsezoic times, we know that the parti-
tions between adjoining zooecia are perforated by numerous
minute pores, and it is of these forms that we may regard the
evidence bearing upon the point in question (presented by thin

BKYOZOA. 313

sections), as reasonably conclusive. But if the peculiar granu-
lar structure of the walls of these Bryozoa is admitted to be
conclusive evidence of their originally porous condition, we must
also admit that the walls of Monticulipora (restricted) and the
CERAMOPORID.E were porous as well, since thin sections of those
forms exhibit precisely the same granular wall structure. The
same also applies to many FISTULIPORHLE.

Nicholson and Ethridge jun. claim to have discovered "mural
pores'' in species of Stenopora*. Unfortunately for the discovery
the very illustrations which these observers give to show these
structures, also show in on unmistable manner that the dis-
covery is founded upon faulty observation. Their new species
S. jackii is said to exhibit the "mural pores" in a more satis-
factory manner than any of the others studied by them. Three
figures are given, two of them (b, c) enlargements of a, repre-
senting a vertically split branch. The explanations to the
figures set forth that b and c show the annulations of the tubes
in their outer portions and the mural pores. A knowledge of
the minute structure of Stenopora,, such as we must believe these
authors possessed, should immediately have explained certain
peculiarities which are presented by the specimen figured. The
authors ought furthermore to have seen that the form of the
tubes ascribed by them to S. jackii is totally different from
that of £ ovata, Lonsdale, in being brought into contact with
each other only at subregular intervals by periodic ring-like
swellings, instead of being in contact throughout their length.
On the other hand, a little more careful examination would,
perhaps, have revealed the fact that the interspaces between the
supposed tubes correspond exactly with the walls of a Steno-
poroid as they appear in vertical sections. The fact of the
matter is that these usually so cautious observers were mislead
bj* a peculiar, yet not uncommon state of preservation, con-
sisting, namely, of the dissolving or wearing away of the actual
walls of the zoarium, whereby the siliceous or semi-siliceous
casts of the interior of the tubes is exposed to view. Specimens
of S. carbonaria Worthen, from the Coal Measures of Illinois,

*Ann. & Mag. Nat. Hist. 1879, VoL IV, p. 275.

—39

314 PALEONTOLOGY OF ILLINOIS.

exhibit the same condition precisely when they have undergone
some weathering. With this new light upon the subject, Steno-
pora once again reverts to the imperforate forms, since we have
no conclusive evidence showing that any true species of the genus
possessed perforate walls.

That some at least of the structures mentioned in the section
devoted to "median tubuli" aided in the inter-communication
of the zocecia, I cannot doubt, but nothing comparable to the
communication plates of the CHEILOSTOMATA has yet been recog-
nized in their Palaeozoic ancestors. As only the "immature" or
prostrate region of the zocecia of Ptilodictya, and other genera
of that type, is equivalent to the ordinary Cheilostomatous
cell, the communication plates, if they existed at all, ought to
be found in the thin walls that separate the zooecia in that
region.

VII. Opercular structures, diaphragms and cystiphragms. —
Opercular structures seem to have been present in most Bryo-
zoa, yet among fossil forms they are of extremely rare occur-
rence. Among the CHEILOSTOMATA their absence is readily ac-
counted for by the fact that the operculum in these is incapa-
ble of preservation, since it is composed of horny substance. In
the CRYPTOSTOMATA, which are Palaeozoic representatives of the
CHEILOSTOMATA, the operculum was most probably also horny.
In many cases, however, notably the FENESTELLID.E, the second-
ary or superficial aperture was closed by a thin centrally per-
forated plate, which, most probably was not developed till at
the final period of growth. This seems to be shown by the
absence of diaphragms in the tubular orifice beneath it, and the
fact that the plate has been observed in fully matured examples
only. This plate has also been detected in tangential sections
of very old examples in which the zocecial orifices are covered
with a dense layer of sclerenchyma having the same structure
as the dense substance of the non-poriferous side of the branches.
In these sections the central perforation in the operculear plate
is surrounded by numerous minute dark spots, which probably
represent former pores. Among the CYCLOSTOMATA the zocecial
tube is similarly closed by a perforated frail calcareous plate
situated usually a short distance from the aperture. This plate

BRYOZOA.

315

I have detected in the tubes of several Palaeozoic CYCLOSTOMATA,
but unless it is terminal (see pi. XXIV, fig. 2,) the closest
search may fail to reveal it.

Fig. 5.— Six illustrations showing various forms of opercular covers, x 50. a, perfect
aperture of Pinnatopora stellipora Y. & Y. b, perfect aperture of Callopora ramosa
d'Orb. c, aperture of Stenopora tuberculata Prout. d, aperture of Polypora bisermta,
having the central perforation of the cover closed, e, Meekopora clausa UL; /, Fistuli-
pora foordi UL

In typical CYSTODICTYONID.E and some FISTULIPORIDJE (e. g. F.
foordi, PI. XLVIII, fig. 7,) the larger portion of the aperture is
often found closed by a plate. The remaining open portion is
of circular outline and occurs immediately within the lunarium.
In Meekopora, clausa (pi. LXXVII, fig. 7,) and other FISTULJ-
PORID.E, the perforation in the opercular plate is sub-central.
When in a good state of preservation the zooecial tubes of
Callopora, Stenopora and several species of Batostomella are
closed by a centrally perforated opercular structure. Ordinarily
the perforation is surrounded by a slight rim and the whole
plate may be either slightly concave or convex and smooth. In
Cnllopora elegantula Hall, C. ramosa d'Orb, and other species
of the genus, six to ten small ridges radiate from the perforated
centre to the margin, giving the false appearance of a septate
aperture. These structures, as they occur in the TREPOSTOMATA,
are most certainly not developed only at the final period of
growth, as some authors have thought, but we have abundant
evidence to show that what at one time served the purpose of
a cover to the zocecium, next formed the floor of the succeed-
ing cell; in other words, became a "diaphragm." Furthermore,
there appears to be no reason to doubt that this process was
carried on throughout the extent of the "mature region" since

316 PALEONTOLOGY OF ILLINOIS.

in tangential sections of these forms the opercula of previous
cell-layers are often recognizable. Their recognition is especially
easy in Stenopora, since in species of that genus the central per-
foration generally remains open. Occasionally an exceedingly
thin membrane is stretched across. In Callopora the perfora-
tion is closed by a secondary deposit and cannot be detected
excepting when it differs in color from the rest of the plate.
The calcareous plates which cross the tubes in the immature
region of the zoarium in the Bryozoa under consideration, seem
to have been without perforations of any kind, but so far as we
can determine, they are precisely like the true "diaphragms."
The latter are probably the most characteristic feature of the
TREPOSTOMATA, occurring, perhaps without any exception, in
all the members of this suborder. They consist of simple calca-
reous plates, flat, or convex, which cross the zocpcial tube at
near a right angle. In all cases they occur at shorter intervals
in the mature region than in the immature, while in the meso-
pores the diaphragms are also comparatively more numerous
than in the zocecia. Idiotrypa parasitica is an exception to the
last rule, since in that species the diaphragms occur upon the
same level in all the tubes. In Dekayia and Dekayella, at
certain periods in the growth of the zoarium, a thin pellicle is
drawn over greater or smaller patches of the surface, while
other portions have the cell-apertures open. This membrana-
ceous covering was doubtlessly developed at the final period in
the existence of the zooids of each layer of cells, and after form-
ing the floor of the succeeding layer, ultimately became a
diaphragm.

True diaphragms are of very rare occurrence among the
Cryptostomata, but in species of Ptilodictya Lonsdale (Hetero-
dictya Nich.), the larger specimens are composed of more than
one layer of cells. Each layer is marked by an inferior and
superior hemiseptum (just the same as the original cell) which
in vertical sections might be mistaken for diaphragms.

BRYOZOA.

317

Fig. 6. a, vertical section of Ptllodictya variabilis TJL, x 35, showing several hemi-
septa; b, half of a slightly oblique vertical section of Ptilodictya maculata UL, showing
peculiar hollow spine-like processes projecting into the zocecial cavity.

Upon careful examination it will be noticed that the supposed
diaphragms spring alternately from the two walls, and that
they do not extend to the opposite wall but terminate at some
point between them.

The peculiar structures which I have called cystiphragms are
very characteristic of some of the most typical TREPOSTOMATA.
They are best shown by and almost restricted to the MONTI-
CULIPORID.E, comprising the genera Afonticulipora, Peronopora,
Prasopora, Homotrypa, Homotrypella and AtactoporeUa.
When examined in vertical sections of these genera, the cysti-
phragms are seen to form a series of lenticular vesicles on one
(rarely both) sides of the zocecial chamber. They are usually
joined to each other in such a way that they present the ap-
pearance of overlapping curved lines. In tangential sections the
vesicles are seen to extend around about two-thirds of the cir-
cumference of the cell chamber (or sometimes to encircle it)
their cut edges giving the appearance of an enclosed eccentric
tube within the zooecial cavity. The space between the inner
margin of the cystoid series and the opposite wall is inter-
sected by horizontal plates or ordinary diaphragms, which may
be as numerous as the cystiphragms. In species of Prasopora
(e. g. P. oculata and afiinis Foord, and P. selwyni Nich.,) the
cystoid diaphragms are often isolated so that they do not touch
each other at all. In this condition the structures compare very

318

PALEONTOLOGY OF ILLINOIS.

favorably with certain interzooecial vesicles which I have ob-
served in Ceriocava ramosa d'Orb., from the Cretaceous of
France.

Fig. 7. a and 6, transverse and vertical sections of Prasopora lycoperdon Vanuxem,
showing the usual type of cystiphragms. c, vertical section of Prasopora affinis Foord,
showing the isolated cystiphragms. d, small portion of a zooecial tube of Amplexopora
robusta UL, showing a funnel-shaped diaphragm supposed to be a modified cystiphragm.
e and /, transverse and vertical sections of Ceriocava ramosa, d'Orb., showing, beside
the spinelets and peculiar wall- structure, two vesicles that are supposed to be homologous
with the cystiphragms.

In the accompanying cut I have figured sections of this species
for comparison with sections of Silurian forms having cysti-
phragms. In the Cretaceous form the vesicles are sub-spherical
and may be attached to the zocecial wall, or suspended from
the radiating spinelets so as to hang apparently free in the
zocecial chamber. In the first instance they resemble the
isolated cystiphragms of Prasopora affinis Foord, in a marked
manner, and I do not think there can be any question that we
are dealing wish structures in every way homologous with
true cystiphragms*.

* Since the above was written I have detected very similar structures in an unde-
termined species of Fistulipora from the Hamilton group of New York.

BBYOZOA. 319

Lastly in Amplexopoia, cingulata, A. robust a, and other
forms, we have certain structures which may be peculiar modi-
fications of the ordinary cystiphragms. These occur in the tubes
near the surface of the zoarium. In vertical sections of these
species (fig. 7d) the first or innermost appears as two convex
lines which spring out from each wall and extend about one-
third of the diameter of the zooecium into its cavity. Above
these another pair of convex lines run parallel with the outer
half of the first pair, and after approaching each other quite
closely form a tubular prolongation, which extends some dis-
tance down into the space between the first pair. In tangential
sections they appear in the zooecial cavity as too circular lines,
of which the larger one encloses the smaller. From these ap-
pearances, it is clear that the first was of hour-glass shape, and
the second funnel-shaped.

At the present time I am not prepared to offer a satisfactory
explanation of the cystiphragms. I may be permitted, however,
to suggest that they were in some way connected with the re-
productive functions.

VIII. Lunarium— This important character, with slight
modifications, is found in the CERAMOPORIILE, CYSTODICTYONID.E
and most of the FISTULIPORID.E. In its typical and most com-
mon form it is a more or less nearly semicircular portion of
the posterior half of the zooecial walls. The ends of the semi-
circle or crescent project into the zooecial chamber to a variable
degree, depending upon the comparative length of the radii,
being greatest when the radius of the semicircle is shortest.

320

Fig. 8. Six illustrations showing modifications of the lunarium. a. Fistulipora
astrica TJL; b, Crepipora simulans Ul.; c, Anoloteichia ponderosa UL; d, Cystodictya
occellata Ul., one of the zooecia divided horizontally just above the primitive orifice ;
e, vestibule of a cooecium of Cystodictya gilberti Meek, cut transversely just beneath
the external aperture; /, zooecium aperture of Buskopora.

In the above cut, a, representing a tangential section of a
zooecium of Fistulipora astrica UL, shows the lunarium in its
normal form; b, shows the true "crescent" as it appears in
Crepipora and other Ceramoporids. Here the outer or convex
line of the crescent is sharply defined, the inner much fainter,
and the intermediate space filled with nearly transparent struc-
tureless substance; c, is apparently intermittent, or traversed
in a longitudinal direction by minute tubuli, which vertical
sections (pi. XLI, fig. 3c,) show to have been intersected by
numerous diaphragms - d, represents a zooecium of Cystodictya
just about to pass in the mature stage ; e, the cell just beneath
the external orifice. These show that the lunarium is not devel-
oped excepting in the vestibular portion of the zooecium. In
Buskopora (fig. f.) we see a decided modification. In this re-
markable genus the lunarium is formed by the channeling of an
internal ridge which projects far into the zooecial chamber. In
Cystodictya gilberti Meek, and Coscinium cribriformi Prout, (PI.
XLIII, fig. 7, 8) the crescent is also very prominent (especially
near the edge of the zoarium) but it is a much less separate
structure.

IX. Wall inflections. — Nothing that will compare with the
' 'septa" of a coral, nor even the imperfect spiniform septa of

BRYOZOA. 321

so many of the FAVOSITID.E has yet been detected in any bryo-
zoan. In a number of forms, however, there are indentations
of the wall which a superficial observer might mistake for such
structures. In most cases these inflections are produced by the
developement of "acanthopores" in the walls of the zooecia.
They are well shown in Atactopora, Atactoporella, Amplexopora
septosa, Batostoma implication Nich., and Heterotrypa inflecta.
In a few other cases of which Actiuotrypa peculiaris Rominger
(PI. LXXVII, fig. 3, 3a, 3b) and Glyptopora keyserlingi Prout,
may be mentioned, there are vertical ridges on the inner side
of the walls, which are not produced by acanthopores. In A.
peculiaris these ridges terminate at the surface as spine-like
projections on the peristome of the cell. Their number, though
varying from six to ten, is usually eight or nine. When exam-
ined in tangential sections they are found to be best developed
near the surface, and that, as the section cuts the zoarium at
a deeper level, they gradually become more and more obtuse
till they are no longer recognizable, the cell aperture having at
the same time been traced to its primitive circular form. In
Glyptopora keyserlingi the inflections are both less numerous
and less defined, as well as much more irregular. Ordinarily
two of them occupy positions in the wall opposite to the
lunarium.

In the species of Ptilodictya (especially the section of the
genus typified by P. pavonia D'Orb., and P. maculata) I have
often observed certain tooth-like processes which project, from
the walls into the interior of the visceral chamber. In large ex-
amples of P. maculata and P. MH, they are often very numer-
ous, several tangential sections of the first species now before
me exhibiting from two to four in each cell. I have also re-
cognized them in vertical sections of this species, (see fig.
6b) but here they sometimes look so much like perforations in
the wall that I originally described them as such.* Perhaps it
is not now possible to give a satisfactory explanation of these
singular projections, still a comparison with several recent Bry-
ozoa may give us a clue to their nature. In the first place we
find that the spine-like projections are developed at correspond-

* Am. Pal. Bry. Jour. Gin. Soc. Nat. Hist. voL V, p. 163, 1882.

—40

322 PALEONTOLOGY OF ILLINOIS.

ing levels in contiguous tubes. This brings us to a point which
ought never to be lost sight of in the study of Palaeozoic Bry-
ozoa. Namely, that in the TKEPOSTOMATA and many CRYPTO-
STOMATA, the tubular zooecium really represents a series of super-
imposed cells. This fact is very well shown in fig. Ga represent-
ing a vertical section of P. vari&bilis. Upon examination, it
is clear that each tube in this section contained two successive
zocecial chambers, each of which was provided with its own
superior and inferior hemiseptum. In P.pavonia and P. maculata
the last structures are repeated at much shorter intervals, but
on account of their extreme delicacy are rarely preserved. Re-
turning to the consideration of the spine-like projections, I find
that they resemble the radiating spines which occur in the
tubes of several species of Heteropora and Ceriocava ramulosa,
D'Orb. In these also the spines are developed at correspond-
ing levels in contiguous tubes. Next I would suggest a com-
parison with the spines which project from the walls and over
the cells in a number of recent species of Membranipora (e. g.
M. spinifera Johnston, M. lineata Linn. (Hincks.)

BRYOZOA. 323

CHAPTER II.

CLASSIFICATION AND INTERRELATIONS OF FAMILIES

AND GENERA.

As thjs work deals solely with Palaeozoic Brjozoa it is quite
unnecessary to enter into the various systems of classification
that have been proposed for the arrangement of Secondary,
Tertiary, and recent representatives of the class, excepting in a
general way. and more in detail when these classifications in-
cluded some of the Palaeozoic types.

D'Orbigny's elaborate classification shows a knowledge of
bryozoan form that stands unrivaled even to-day. His lucid
descriptions and excellent plates reveal a wonderful variety of
structure and an almost endless array of beautiful forms. How
very unfortunate then that a work so laudible should be ac-
companied by an extremely artificial classification, and a
nomenclature so complex that it is bewildering.

D'Orbigny's first attempt at a systematic arrangement is found
in his "Cours elementaire de Palaeontologie," which was shortly
followed by a more comprehensive synopsis of the fossil forms
in the "Prodrome de PalaeoDtologie." Lastly in the ''Palaeon-
tologie Francaise, vol. V" he publishes his completed classifica-
tion, embracing all the forms known up to 1852, making in all
two hundred and nineteen genera and one thousand nine hun-
dred and twenty-nine species. Upon this vast array of bryozoan
diversity he based a wonderfully artificial system, which has
been abandoned, perhaps without an exception, by all subse-
quent authors who have made a special study of Bryozoa. His
two grand divisions, the BR YOZOAIRES CELLTJLINES and BR YOZOAIRES
CENTRIFUGIXES correspond very nearly with Busks CHEILOSTOMATA

324 PALEONTOLOGY OF ILLINOIS.

and CYCLOSTOMATA. and to him, therefore, belongs the credit of
being the first to delineate the two principal divisions of the
GYMNOL.EMATA. His family and generic groups, on the other
hand, have little to recommend them, as they are largely based
upon the most trivial characters, such as the presence or
absence, position and number of the "special pores," complete
and incomplete calcification of the anterior wall, while even in-
dividual peculiarities or conditions due to age are credited with
generic importance. As, however, d'Orbigny is the only author
who has sought to account for the entire field of fossil and re-
cent Bryozoa, the palaeontologist has been obliged, in the
absence of a more natural system, to accept that of this em-
minent French naturalist as an indispensible basis.

With a single exception (Hippothoa inflata Hall,) all the
Palaeozoic species known to d'Orbigny, were placed by him in
his order CENTRIFUGINES (CYOLOSTOMATA Busk) . None of them,
however, really belong there, though true Cyclostomatous Bry-
ozoa were not uncommon in some of the Palaeozoic rocks. As
instances of the unnatural collocations often found in his sys-
tem I may mention Omniretepora (generally supposed to be a
synonom for Fenestrella) Archimedipora (Archimedes Leseur),
the Fenestellid genera Fenestrella, Fenestrellina, Reteporina and
Polypora McCoy, and the ACANTHOCLADIID^E Keratophytes
Schlotheim (Acanthocladia King), Penniretepora, Ptylopora
McCoy, and Ichthyorachis McCoy. The first is found among
the CRESCISIDJE with Heteropora and genera of that type, the
second with the TUBIGERHLE, and all the rest among the SPAR-
SIVM where they are total strangers.

Busk's skillfully devised system* has rendered most important
service in promoting the study of fossil and recent Bryozoa.
For D'Orbigny's CELLULINES he proposed the appropriate name
CHEILOSTOMATA, and this division especially, he sought to divide
into natural families and genera, taking the zoarial characters,
or in other words, the result of the mode of combination of the
zocecia, as of the first importance. With such characters as a
basis he succeeds in dividing the class into convenient and
readily recognized groups, which are particularly adapted for

* "British Museum Catalogue, 3 pts.," "Crag Polyzoa," Palaeontographical Soc. Pub."

BRYOZOA. 325

the easy identification of species. In this respect the system is
not surpassed by any other, but being very largely an artificial
arrangement, it too often gives the student no clue to the nat-
ural relations of his species, which after all must be the first
aim of classification. For this reason, therefore, however well
adapted to the wants of the collector, the system can hold only
a provisional place. In his last worksf Mr. Busk has modified
his system to a considerable extent, so that it now seems much
more in accordance with nature than formerly. Still, while I
am not ready to admit that zooecial characters alone, should
be consulted in the framing of a system of classification, I am,
nevertheless, convinced that even now Mr. Busk credits zoarial
variations with more importance than they deserve. Palaeozoic
Bryozoa have received very little attention from this eminent
authority, and beyond placing some of the well known genera
into his suborder CYCLOSTOMATA, he does not account for them.
Hincks. whose work applies almost exclusively to recent re-
presentatives of the class, foEows and greatly enlarges the
system first proposed by the Swedish naturalist, Prof. F. A.
Sinitt. The latter aims at a genealogical classification, start-
ing with the supposition that the variations of species follow
the line of their development, and may be in a great measure
explained by it. In accordance with this theory he would ar-
range the Bryozoa in series according to the law of their evo-
lution. This doubtlessly opens a most interesting and im-
portant field for inquiry, one that I believe deserves more at-
tention than it has yet received. Still in the present stage of
our knowledge, the morphology of the class will be better ad-
vanced by recognizing and clearly discriminating between the
more constant variations than by uniting them upon grounds,
which only in rare instances can be unquestionable, into com-
prehensive specific groups under a single name. If a genealog-
ical arrangement in detail is ever possible, it will only be after
we have taken into account every departure from the simple
and more permanent types. Hincks himself thinks that Smitt's
arrangement of the Bryozoa in genealogical groups is prema-
ture, and his reduction of species excessive, as well as often
confusing, because unwarranted.

t Challenger Reports.

326 PALEONTOLOGY OF ILLINOIS.

After the feature of Prof. Srnitt's work just noted, the next
important is the value he assigns to the zocecium in the forma-
tion of families and genera, the zoarial characters being on the
other hand treated as perfectly subordinate. His claim is that
the cells themselves, and not the mode in which they combine,
furnish the true test of relationship, and the essential basis of
a natural classification.

As Busk's three orders of the GYMNOL^EMATA are founded upon
structural peculiarities of the cell, they are accepted by both
Smitt and Hinck's. When however it comes to the farther di-
visions of the order into families and genera, we find that the
new system departs very widely from the classifications of Busk
and d'Orbigny. As none of their families are represented in
Palaeozoic Rocks, it is not necessary, at this time, to follow the
system in greater detail.

Unfortunately, none of the supporters of the new classifica-
tion have in any way sought to account for the Palaeozoic
types, so here we find a perfectly free and unoccupied field.
With respect to these the first question that arises is, which
system or classification gives the best results, that in which
the zoa,rial characters are assigned a high degree of import-
ance, or the other in which the zocecium alone furnishes the
test of relationship. If it was necessary to make an absolute
choice between the two systems, I would not hesitate very long
before accepting the second, for it can not be questioned that
differentiations in the cell or actual home of the polypide are
more trustworthy structural variations than the form of the
zoarium. Still, since the latter in a large measure must be due
to deviations in cell structure, it follows that zoarial as well as
zooecial peculiarities should be taken into account in the fram-
ing of a classification, and while it also follows that in their
relative values, the former must necessarily be subordinate to
the latter, we should not overlook the individuality of the
zoarium as a continuous whole or entity, since we do not fully
understand the comparative significance of zoarial and zooecial
characters.

An extended study of Palaeozoic Bryozoa shows me that in
classifying these early types much caution must be exercised,
and that no character or set of characters has the same classi-
ficatory value throughout when applied to a large number of

BRYOZOA. 327

forms. The value of a character must be determined by its
constancy and degree of prevalence, and experience will show
that the value is not by any means the same when observed
in different groups of species. Thus a character may be suffi-
ciently constant in one set of forms to be considered of generic
importance, while in other species the same peculiarity may be
found so variable that its value is almost over estimated, when
we call it specific. As an instance of this variability in the
significance of a character I may mention the two "mesopores"
whir-h are constantly present between the ends of the cells of
Ph&nopora, Hall. In other respects this genus is almost identi-
cal with Ptilodictva Lonsdale. In this case, therefore, the
position and number of the "mesopores" is a generic character.
In Stictoporella and Intrapora Hall, precisely the same kind of
"mesopores" are constantly present, but as they vary in num-
ber and position (even in the same species) their arrangement
in these cases is only of specific value.

This naturally suggests the question, when are we justified in
considering a variation as having generic, specific or only
varietal importance? In the first place, the answer depends
very much upon the views held by the individual who is to
make the divisions. Some authors make genera and species
upon a very small margin, while others give their divisions un-
due latitude. My own plan is simple enough, and so far as I
can see, fills all the requirements of classification, as the result
is a system that is convenient as well as natural. Convenience
is a necessity, and, in the framing of a classification, must be
taken into consideration just as much as the natural relations
of the organisms we seek to arrange. These two necessary fea-
tures of a permanent classification I have sought to furnish in
the system here proposed. With what success will be determined
by future research. That it will be lacking in many points of
minor detail I do not doubt, yet, taken as a whole, I feel con-
vinced that it will meet with favor. Some of the older palaeon-
tologists will doubtlessly object to what they consider my ex-
cessive multiplication of species and genera. The same com-
plaint will come from other naturalists who are endowed with
more than ordinary ability in solving genealogical problems.
The first class of dissenters belong to the old school of natur-
alists, the second are extremists of the new. Opposed to these

328 PALAEONTOLOGY OF ILLINOIS.

is the steady growth of a tendency to provide for all the re-
cognizable stages in the development or evolution of organic
nature.* Perhaps the principal cause for this tendency is found
in the fact that now, more than ever before, naturalists con-
fine themselves to the study of special groups, and it is well
known that specialists, at any rate modern ones, make species
and genera upon small provocation. Their great familiarity
with the minor details of structure may perhaps magnify the
points of difference, but, on the other hand, we must not for-
get that this same familiarity gives them an insight into the
relative values of structural variations which the ordinary stu-
dent cannot possess. As good illustrations I have but to men-
tion the admirable system recently proposed by Zittel for the
classification of the Sponges, Haeckel's work on the RADIOLARIA,
and Wachsmuth and Springer's excellent work on the PAL^EO-
CRINOIDEA. Some of the older authors too, who have kept pace
with the remarkable progress of natural history, and have
adopted modern methods of investigations, offer striking in-
stances of the "tendency." Take for instance Hall's recent
works on Devonian Fossils, Barrande's last, and De'Koninck's
magnificent contributions to the Carboniferous fauna of Bel-
gium. Even more striking in this respect is Davidson's supple-
mentary work on British Brachiopoda. He was, perhaps, the

* Every classification must, to a certain extent, be artificial and arbitrary, since it is
impossible to draw up a system that will follow out all the intricacies of evolutional ex-
istence. Again, the "vanishing lines" of nature forbid our looking for sharply defined
groups or species, consequently our divisions are necessarily more or less arbitrary _
In practice, species gradate almost insensibly by means of intermediate species and
varieties into each other, while the same instability of characters gradually effaces the
separating lines between genera and groups of higher rank. Some authors upon find-
ing the intermediate links between closely allied species are not content with the
knowledge thereby gained, but make use of it by reducing the "excessive" number of
species. I take a different standpoint, and would like to see every recognizable stage
in the evolution of organic beings distinguished from the next by its own name. Now,
whether this stage is ranked as a variety or species, is a matter of very little moment
to me, since in most cases, the palaeontologist at any rate, finds it almost a hopeless
task to define just what constitutes a variety and what ought to be called a species.
My idea of a genus is a more or less arbitrary group of species, having intimate natural
relations to each other. In other words, a greater or less number of species having
certain structural peculiarities in common. Sub-genera I hold are a useless encum-
brance of nomenclature, as there is very little, if any, need for intermediate divisions
between species and genera. So far as I can see they only serve to destroy the uni-
formity of classification in giving an undue rank and latitude to the genera to which
they belong. In many cases these subdivided genera may be said to assume the rank
of families.

BRYOZOA. 329

most conservative of all palaeontological specialists, yet in the
la.st five years of his life he established more new genera than
during the preceding thirty years. With such illustrious pre-
cedents, I feel justified in presenting the following classification
of Palaeozoic Bryozoa, subject to the decision of future workers
in the field.

In making my divisions I have sought to follow nature as
nearly as possible, starting with the propositions, (1) that the
classificatory value of a character is determined by its con-
stancy, (2) that in the aggregate of characters is found the true
test of relationship. From the first proposition it follows that
the constant characters, whether zoarial or zooecial are the
significant ones, that their relative values are according to the
degree of constancy, the degree being determined only by a
comparative study of numerous individuals, species or genera,
as the case may be. By experience we learn that modifications
of certain features are generally more significant than of
others. Thus among th CHEILOSTOMATA the variations of the
apertures, the degree in which the primitive opening is pre-
served or obliterated, and the modifications in the form of the
orifice are very important. In the CYCLOSTOMATA, however, the
zooecium is extremely simple and uniform, so that here the
:natist must depend almost entirely upon variations in the
mode of combination of the cells. When we come to the TREPO-
STOMATA. both the zocecium and zoarium supply us with impor-
tant characters. The same may be said of the CRYPTOSTOMATA,
but among these, perhaps as much as with the CYCLOSTOMATA,
must we take zoarial variations into consideration in making
generic and family divisions. In a general sense this sub-order
may be regarded as representing the Escharina group of the
CHEILOSTOMATA. but the characters which serve so well in class-
ifying the recent forms are almost always obliterated by subse-
quent deposits of calcareous material. Thin sections, of course,

—41

330

PALEONTOLOGY OF ILLINOIS.

Fig. 9. a, Eschara artemis, d'Orb. b, E. argyrias, d'Orb., from the Cretaceous of
France (after d'Orbiguy). c, diagrammatic vertical section of a Cryptostomatous zore-
cium showing the "vestibule" at v, the superior hemiseptum at sh, and the inferior
hemiseptum at ih. d, outline of the primitive porfion of a Cryptostomatous zooecium,
showing the primitive orifice at o, the superior hemiseptum at sh, and the line of the
inferior hemiseptum at ih. e, Small portion of zoarium of a typical Cyclostomatous
bryozoan, (Idmonea serpens Linn., after Hincks).

give us an approximate idea of the primitive cell and aperture,
but as these features are often of quite uniform construction,
we must look to other characters for generic points. These are
supplied by the superficial orifice, the presence or absence of
mesopores, acanthopores, median tubuli and hemisepta, and by
modifications in the form of the zoarium, which, as I have
already indicated, are very constant in this sub-order. The
bilaminar zoarium is very persistent and, perhaps, the most
typical, but the fenestrated forms are more numerous as well as
exceedingly constant in their zoarial peculiarities. This is fortu-
nate, since the small, yet readily recognized variations in the
construction of the zoarium, supply us with excellent points
upon which to found our genera. On the other hand the in-
dividual zooecia of the fenestrated forms, excepting Pliylloporina,
are so uniform that no recognizable peculiarities can be said to

BRYOZOA. 331

distinguish those of one genus from those of another. (Com-
pare sections of fenestrate genera figured on pi. 54 and 56).
Taking this uniformity into consideration it seems evident that
the Silurian species which 1, have united under the genus Pbyl-
loporina, are sufficiently distinguished from the FEXESTELLID.E
to rank as a separate family. Indeed, the tubular zocecia, which
are occasionally intersected by diaphragms, suggest a decided
affinity with the TREPOSTOMATA and CYCLOSTOMATA. Granting
this relationship, we must not lose sight of the fact that a
tubular primitive cell is also characteristic of many of the
ARTHROSTYLOXE, and all of the RHABDOMESONTID.E as well as
occasionally in other families of the sub-order (e. g. Stictoporella,
and Phyllodictya ) . It also appears highly probable that in
Fhylloporina we see the ancestors of the more highly developed
FEXESTELLID.E. A comparative study of that family brings to
light some important facts. Thus the earliest of the species
really belonging to the restricted genus Fenestella, differ from
the typical Devonian and Carboniferous species in having the
thin walled primitive cell more inclined to be tubular; or per-
haps it would be better to say, that the anterior and posterior
walls are less nearly vertical than we find them in later repre-
sentatives of the genus. On plate 54, fig. 2, represents a deep
tangential section of a branch of F. bellistrmTa (?) Hall, from
the Niagara shales at Waldon, Ind. This should be compared
with 16 on same plate, representing a similar section of Pbyllo-
porina ? dawsoni, from the Trenton group at Montreal, Canada,*
and it will be seen that they have one peculiarity in common
which is not possessed by the Devonian and Carboniferous
species represented by figures 3, 4, 5. Namely, the partitions

PHYIXOPOBIXA DAWSONT, n. sp. Branches lax, very slender, 0.3 to OJ> num. wide,
irregularly inosculating, often united by non-poriferous dissepiments. Fenestrules
acutely elliptical, usually wider than the branches and from 1.5 to 3.0 m.m. long. Reverse
convex, smooth or faintly striate. Poriferous side with a sharply angular! mesial ridge
and one range of cells on each side. Zocecia sub-tubular, with rather prominent sub-
circular apertures. 0.18 num. in diameter, five or six in 2 m.m. Tangential sections show
a number of minute accessory pores in the interspaces between the apertures.

The reverse of this species very much resembles that of P. reticulato. Hall, from
the same foi mation, but sections of the two forms cannot be confounded. Hall's species
has three ranges of zooecia and generally has smaller fenestrules.

Quite abundant in the Trenton strata at Montreal, Canada, and Chimney Point, Ver-
mont Specimens were received from Sir Win. Dawson and Prof. H. M. Seely.

332 PALEONTOLOGY OF ILLINOIS.

between the ends of the cells are directed obliquely upward and
outward from the mesial line, instead of at a right angle. P. ?
dawsoni, agrees also with Fenestella in having only two series
of cells separated by a mesial carina, and the branches united
by non-poriferous dissepiments. Taking all these characters
into consideration, I think we are justified in regarding P. ?
dawsoni as one of the ancestral types of Fenestella. On the
other hand, the rather prominent and but slightly contracted
cell-orifice point to a relationship with the Cyclostomatous
genus Protocrisina, sections of which are figured on plate 53.

A careful study into the minute structure of the various spe-
cies of Phylloporina almost forces the conviction upon us that,
at some time before the commencement of the Trenton epoch,
there existed Bryozoa \which combined characters that during
subsequent ages became separately specialized and characteristic
of widely different groups. Take for instance P. trentonensis
Nicholson sp. Sections of this remarkable form remind us very
strongly of typical TREPOSTOMATA, the angular cells, their long
"immature" region, and the closely tabulated mesopores, all
being present in species of that suborder. The resemblance is
heightened in vertical sections of P. corticosa, by the addition
of diaphragms in the tubular zooecia. The last species has also
a very prominent mesial carina running along the centre of the
branches very much as in Semicoscinium. The relationship
thereby suggested is, however, in no wise born out by further
comparison.

In P. aspera Hall, P. reticulata Hall, F. dawsoni n. sp. and
P.asperato-striata H.,the zooecial tubes are shorter, approaching
the Cryptostomatous cell. In the last species the interstitial
spaces are occupied by angular mesopores which have been
filled by secondary deposits of sclerenchyma. In Drymotrypa
dichotoma n. sp. we have a species in which the zooecial struc-
ture is not unlike Phylloporina, but the branches bifurcate fre-
quently and are not united by anastomosis as in that genus. The
general aspect, therefore, is not at all unlike that of a small
species of Thamniscus. That genus, however, has the short
cells characteristic of the FENESTELLID^E and never has dia-
phragms. There are some points also which suggest comparison
with Protocrisina.

BRYOZOA. 333

The theory which is suggested in the foregoing paragraph is
corroborated by similar comparisons between early Palaeozoic
and more recent representatives of perhaps every class of the
Invertebrata. It is well shown in the Mollusca and is especially
apparent in those classes that are largely represented in recent
seas. The student of Palaeozoic fossils is continually beset with
obstacles in his endeavor to classify his species, finding over
and over again that the rules which serve so well arrange
recent material, do not apply to the Palaeozoic faunas. To this
is attributable much of the confusion which pertains to palaeo-
zoology, since, according as the student emphasizes one or the
other character, the fossil is removed from one family to another.
Is there no remedy for this deplorable state of affairs? The
remedy will be at hand when palaeontologists generally will
have come to realize the vastness of their science, and the im-
portance of accurate and discriminative observation of the min-
ute details of structure. This is the pressing necessity, a min-
ute inquiry into the morphology of Paloeozoic life, and the in-
evitable result, — a better idea of Palaeozoic geneaology, — can-
not fail to produce harmony wThere we now have utter confu-
sion. A superficial observer determines the affinities of a fossil
very quickly; not so the careful student. He has learned to
esteem caution, because he sees how very easy it is to misin-
terpret a character, and how extremely difficult the task of cor-
relating the ancient types with the living. A full appreciation
of this difficulty may have led me to propose and adopt divi-
sions that workers on recent Bryozoa may object to in the be-
ginning. Thus the suborder CRYPTOSTOMATA lately proposed
by Mr. Vine, includes forms which there can be little doubt are
to be regarded as the ancestral types of a large proportion of
the CHEILOSTOMATA. In fact, the CRYPTOSTOMATA really repre-
sented that suborder in Palaeozoic times, and we might with
with much propriety unite the two groups. Still, as all the
Palaeozoic forms have certain peculiarities in common in which
they differ from the true CHEILOSTOMATA, the better course, at
any rate now, is to keep them separate.

The order GYMNOLJSMATA includes, so far as known, all the
fossil Bryozoa. The bulk of those in the Palaeozoic rocks I

334 PALAEONTOLOGY OF ILLINOIS.

have arranged under three suborders: CYCLOSTOMATA, TREPO-
STOMATA and CRYPTOSTOMATA, while the CTENOSTOMATA and
CHEILOSTOMATA also seem to have had a meagre representation.

I. Ctenostomata. — These Bryozoa as they are known in the
recent state, are characterized by a horny or membranous test;
on which account it is generally supposed that they have not
been capable of preservation by fossilization. One of their lead-
ing characteristics is the curious opercular mechanism of the
zooecium. The upper portion of the cell wall is thinner than the
rest, and terminates above in a number of delicate setae held
together by a thin transparent membrane. When the polypide
retreats the whole of this anterior portion is drawn in, and the
setae, being brought close together, form an operculum-like cover-
ing above the tentacles. The zoarium is often creeping, with
the flask-shaped zooecia arranged in single series resembling
Hippothoa and Stomatopora. Frequently the zooecia stand erect
upon a cylindrical stem, while in other cases they are immersed.

As already stated the horny membranous test is strongly
against finding fossil remains of CTENOSTOMATA, still there are
two Palaeozoic genera that agree so nearly in habit with certain
recent members of the suborder that I can not do otherwise
than place them together. These genera are Ascodictyon Nich.
and Eth. jr., and Rhopalonaria* The genus Ascodictyon was
established by the authors cited for the reception of certain
problematic fossils which occur usually as radially arranged,
extremely delicate fibres on shells, etc. The fibres vary in length
and are sometimes bulbous or inflated at intervals. In a few
cases, too, the fossil consists of small clusters of bulbous vesicles
which are arranged in a radial manner. When more than one
cluster is preserved they seem to be connected to each other by
a thread-like fibre. The substance of the fossil appears to be
corneo-calcareous. Ascodictyon may be compared with species
of Valkeria, Bowerbankia and Cylindrcecium, as figured by
Hincks (British Marine Polyzoa). The Silurian genus Rhopalo-
imitates Hippothoa in its zoarial habit. The zooecia are

* Since the above was written I have learned that in the Ann. & Mag. of Nat. Hist
for Aug., 1884, Mr. Vine in discussing these two genera, suggests a comparison with the
stoloniferous VESICULABID^: (CTENOSTOMATA).

BRYOZOA. 335

slender spindle-shaped, united to each other by their extremely
attenuated terminations, or by an uninflated filiform tube. The
substance of the zoarium is very thin, dark brown or black,
and only rarely preserved, but on account of its curious habit
of excavating the substance of the body upon which it grew,
the form of the zoarium, as well as that of the zocecia is gen-
erally clearly defined and recognizable. The orifice is small, in-
distinct, and readily overlooked in the best specimens at hand.
Khopalonaria compares favorably with species of Arachni-
diuni Hincks; A. clavatum Hincks (loc. cit. pi. 71, figs. 3,4,5)
is especially recommended.

The species of Ascodictyon and Rhopalonaria should perhaps
be placed in distinct families, but, as it is not probable that
either one of the genera belongs to any of the recent families,
and as our opportunities for comparison between fossil forms of
the suborder are necessarily very limited and unsatisfactory, I
regard it sufficient for present needs to arrange the Palaeozoic
species in one family, the ASCODICTYONID^E.

II. Cyclostomata. — The forms of this suborder are character-
ized throughout by simplicity of structure, the zocecia being
always tubular, with the mouths simple, rounded, inoperculate,
and generally exert; the walls thin, of nearly uniform thickness
throughout, and minutely perforate; all appendicular organs
are wanting. The polypide also is more than usually simple in
structure, has comparatively a small number of tentacles, while
the larva? of the principal families are almost identical. It is
really a very difficult matter to divide this suborder into satis-
factory families and genera. On account of the extreme sim-
plicity and uniformity of the zooecium, we must depend almost
entirely upon variations in zoarial habit and mode of zooecial
aggregations. These are generally striking, and among Palaeo-
zoic forms at any rate, usually reliably indicative of true rela-
tionship. Thus, while in Mitoclema the zooecial tubes are long
and radiate equally in all directions to open on all sides of a
cylindrical stem, they are shorter, beaded proximally, and those
opening on each side of the compressed branches, are separated
by an axial plane in Diploclema. Protocrisina again differs
from both in having one side of the branches without cell aper-
tures.

336 PALAEONTOLOGY OF ILLINOIS.

True CYCLOSTOMATA appear already in the Chazy horizon of
the Lower Silurian, from which the author has described Mito-
clema cinctosum. This species, though probably belonging- to
the same family as Entalophora Larax., differs from species of
that genus in several important particulars*. The axial region
of vertical sections is more like what we find among ramose
TREPOSTOMATA or CRYPTOSTOMATA.

In the Trenton proper we find already a fair representation,
the following genera having been determined: Stomatopora
Bronn, Berenicea Lamx., Scenellopora, Protocrisina, Diploclema
and Phacelopora, each with one or two species. Individuals
of these forms are rather uncommon, but with the beginning of
the Cincinnati group both species and individuals become more
abundant. Scenellopora is not yet known from these rocks, but
another group of species nearly related to Stomatopora, and
apparently congeneric with the species for which Audouin pro-
posed the genus Proboscina, now make their appearance. In
Upper Silurian deposits I have detected only Berenicea (Sage-
nella Hall) two species, Stomatopora, one, Diploclema one or
perhaps two. For Devonian forms that may belong here, Hall
proposes several genera, but no true CYCLOSTOMATA are as yet
known from the Carboniferous rocks. Thus it seems that the
suborder was better represented during Silurian times than at
any subsequent time before the beginning of the Jurassic de-
posits. Several interesting facts are brought out by a compari-
son of these ancient types with their much more numerous
Mesozoic relatives.

*In a paper on Australian Bryozoa, Mr. A. W. Waters not only thinks Mitoclema
the same as Entalophora, but he identifies the Chazy form with E.verticillata Goldfuss,
a Cretaceous species. Mr. G. B. Vine (Kep't on Eec't. Poly.), however, thinks the species
distinct and only the genera synonymous. These gentlemen arrived at their hasty and
erroneous conclusions without examining specimens, and as the internal structure of
Mitoclema cinctosum had not yet been made public, they should have deferred their
condemnation. When I proposed Mitoclema I was acquainted with over twenty species
of Entalophora (Spiropora). All of these possessed one peculiarity which I could not
find in my species, namely, all the zooecial tubes of EntalopJiora originate along the
axial line of the branch, and gradually increase in diameter as they curve outward
toward the surface. An end view of the branch shows the very characteristic arrange-
ment of the tubes in intersecting curved radial lines. As I have said, this peculiar ar-
rangement is not present in the Silurian species, and I consider myself justified in pro-
posing a new generic name for it.

BRYOZOA. 337

Species of Stomatopora and the closely allied divisions Pro-
boscimi and Bei-enicea from Cincinnati, Ohio, differ in no appre-
ciable manner from Jurassic and Cretaceous species, while
Mitoclema, Diploclema, Protociisina, and Scenellopora, closely
resemble Entalophora, Bidiastopora, Crisina, and Defrancia, re-
spectively. Of all the Silurian forms the two species of Phace-
lopora are probably the most distinct, yet, even these admit of
comparison with some of the TUBULIPORHXE.

The large size of most of the Devonian forms makes it some-
what doubtful that they are really Bryozoa, still their general
aspect is so much like that of typical CYCLOSTOMATA that I do
not see how they can be placed elsewhere. To determine the
question beyond dispute requires a more minute study than I
have found time to give them.

III. TREPOSTOMATA: — The zoaria of this suborder are com-
posed of prismatic or cylindrical tubes, that change more or
less in character as they pass from the "immature'' into the
"mature" region. In the ''immature" region the tubes have
extremely thin, prismatic and simple walls, while horizontal
diaphragms may or may not be developed here. The "immature"
region of a zooecial tube is longer in the ramose forms, than
in the lamellar and parasitic, and is equivalent to the primitive
cell of the CHILOSTOMATA and CRYPTOSTOMATA. The transition
from the "immature" to the "mature" condition is often grad-
ual, but more generally rather abrupt, though never so much
so as in the CRYPTOSTOMATA. The change consists of (1) a
thickening of the walls, (2) the development of mesopores, and
(3) an increase in the number of diaphragms. Opercular struc-
tures and perforated diaphragms also only occur in the mature
region. Each stage in this region marked by the diaphragms,
represents a layer of zooecia, each of the individual chambers
having been developed in direct sequence from the zooecium im-
mediately beneath it. By repeating the process a tabulated
tube resulted.

This suborder, though having living representatives, attained
its irreatt'-T development during Palaeozoic times. In Mesozoic
and more recent times the distinctive characters are largely
subdivided, and, by equal concessions on the part of the CY-
CLOSTOMATA, the dividing line between the divisions has become
-42

338 PALEONTOLOGY OF ILLINOIS.

somewhat shadowy and certainly much less sharp than we find
it to have been during the early periods of their existence. So
little is known of the internal structure of Mesozoic CYCLOSTO-
MATA and TREPOSTOMATA that it is not now possible to dis-
tinguish satisfactorily between them. It would be presumptive
on my part to attempt it. In a general way. however, it may
be said that the Mesozoic types which are provided with meso-
pores, such as the majority of the genera referred by d'Orbigny
to his families, CLAUSED js, CAVEID.E, CAVID.E and CRESCISID.E, are
not true CYCLOSTOMATA but rather TREPOSTOMATA.

The Palaeozoic genera I have grouped under the nine families,
MONTICULIPORID.E, HETEROTRYPID^E, CALLOPORID^E, TREMATO-
PORID.E, BATOSTOMELLULE, AMPLEXOPORID.E, DIPLOTRYPID.E, CER-
AMOPORID.E, and FISTULIPORHLE. The first may be considered
as the most typical, as the forms which constitute the family
contain all the more characteristic features of the sub-order.

(1) MONTICULIPORHLE: — The zoarium in this group comprising
the genera Monticulipora, Peronopom, Atactoporelki , Praso-
pora, Homotrypa and Homotrypella, may be massive, discoid,
lamellar or incrusting, while the bifoliate and ramose forms are
also frequent. The zocecia are prismatic, rounded, or irregu-
larly petaloid. with comparatively thin walls, having a peculiar
granular structure. The mesopores vary greatly in number,
being sometimes apparently absent or very few, at other times
very numerous. Occasionally they are obscured by a secondary
deposit of sclerenchyma. Zooecia with cystiphragms, the meso-
pores with horizontal diaphragms. The acanthopores are nearly
always small, and generally numerous.

The family as above restricted contains a large number of
mainly Lower Silurian Bryozoa, whose principal character, the
cystiphragms, has, so far, proved an almost infallible distin-
guishing mark. In the genus Monticulipora (e. g. M. lamellosa
and M. winchelli) these structures are often modified so that
they might be mistaken for simple, oblique or slightly curved
diaphragms. Experience, however, will soon dispel the illusion.
The genera of the family are separated from each other mainly
by constant zoarial peculiarities, though each also has its own

distinguishing zooecial features.

*

BRYOZOA. 339

(2) HETEROTRYPID.E: — The zoarium in this family is fronde-
scent, ramose or iiicnisting. Usually the zooecia are polygonal,
more or less contiguous, with comparatively thin walls. In
other cases rounded or oval. The mesopores, though always
present, vary greatly in number, being exceedingly few in some

(Dekayia). and quite numerous in others (species of De-
kayella.) Acanthopores are always present, sometimes being
of very large size (Dekayia). Generally they are small and
placed at the angles of junction between the zooecia. Their
cavity, too, is usually very small, but in species of Batostoma
it is larger than in any other member of the TREPOSTOMATA.
No cystiphragms are present, and the diaphragms are always
horizontal and conspicuously more numerous in the meso-
pores than in the zooecial tubes. Another peculiarity fre-
quently met with, especially in species of the typical genera
of the family, is the closing of the cell apertures on limited or
extended portions of the surface by a thin, apparently imper-
forate calcareous pellicle.

The four genera, Heteroti'ypa Nicholson, Dekayia Ed. & H.,
Dekayella. and Petigopora constitute the family as here under-
stood. These genera clearly have natural affinities, differing
from each other only in the number of mesopores, thickness of
zooecial walls, and in the form of the zoarium. Thus Hetero-
trypa is characterized by moderately thick-walled zooecia, com-
paratively few mesopores, and a frondescent or compressed
habit of growth; Dekayia by its thin walled zooecia, a ramose
or subramose zoarium, and by the practical absence of meso-
pores: Dekayella by the numerous mesopores, and two sizes of
acauthopores: and Petigopora by the parasitic habit of growth
and nou-celluliferous epithecal margin.

(3) CALLOPORID.E:— The zoarium in this family may be dend-
roid, subfrondescent, discoid, or, rarely, sub-pyriform. The
zo<Hda are sometimes polygonal, bu.t usually sub-circular, and
separated from each other by numerous angular mesopores,
which, when the zooecia are rounded, more or less completely
isolate them. Zooecial walls generally thin, rarely thickened
and ring-like in transverse section. Cystiphragms are wanting,

340 PALEONTOLOGY OF ILLINOIS.

while small acanthopores are only occasionally present. The
apertures of the Booecia are closed by centrally perforated plain
or radially striated opercula.

This family is proposed provisionally for the reception of the
three genera Callopora Hall, (restricted, Ulrich), Calloporella,
and Aspidopora, which have the above noted peculiarities in
common. The opercular covering of the zooecial aperture is
considered the principal distinguishing feature. The genera are
separated by easily recognized characters, Callopora having a
ramose zoarium, thin walled, polygonal or sub-circular zooecia,
a varying number of mesopores, and no acanthopores. The
last structures are developed in moderate numbers in both
Calloporella and Aspidopora, the zoarium in both again being
discoidal and free, with a concentrically marked epithecal mem-
brane on the concave under side. The first is distinguished
from the second by having thick ring-like walls to the zooecia
and different mesopores.

(4) TREMATOPORID.E: — Ramose, irregularly frondescent, or para-
sitic zoaria pertain to forms of this family. The zooecial tubes
are thin- walled, adjoining and prismatic in the "immature"
region, subcylindrical or more or less completely isolated by
abundant angular mesopores in the "mature" region. The
zocecia apertures are circular, oval, or petaloid, with a more
or less distinct peristome, while the mesopores are closed at the
surface by numerously perforated closures, the perforations ap-
pearing as small hollow spines or granules. Both sets of tubes
are intersected by horizontal diaphragms, but acanthopores are
often wanting. Neither cystiphragms nor opercula have been
observed in any of the species.

The family comprises a number of peculiar and several very
beautiful Bryozoa, that suggest affinities, more strongly than
any other Palaeozoic genera, with Mesozoic types of the TRE-
POSTOMATA. Thus Trewatopora compares well with Heteropora
and other genera of that type, while Constellaria and Stellipora,
closely resemble d'Orbigny's genera Multicava, Domopora and
Radiopora.

The family includes besides the three genera already mentioned
also the new genus Nicholsonella, Idiotrypa, and most prob-
ably Dittopora of Dybowski. The last is little known, and I

BRYOZOA. 341

have not met with any species having the characters ascribed
to the genus by its author. The others are distinguished by
easily recognized structural peculiarities and corresponding
zoarial features. Leioclema, now referred with some doubt to the
next family, may prove to have closer affinities with Tremato-
pora than I am at present disposed to admit.

(5) BATOSTOMELLID.E. The zoaria of this family vary ex-
ceedingly in shape, but are never bifoliate. The ramose habit
of growth pertains to a majority of the species. In the "ma-
ture" region the zooecia have thick walls, usually appearing
here as though fused together. Here too the diaphragms are
centrally perforated, having originally functioned as covers to
the zooecia apertures. Specimens preserving the opercular covers
are rare, and it is only in some of the Carboniferous forms that
the perforations are invariably shown by good thin sections of
the peripheral or mature region. Mesopores are usually present
and sometimes abundant, but they are often intermittent, and
generally without distinct walls and diaphragms. Acanthopores
well developed. Intramural dots are also shown in tangential
sections of most species.

The six genera Batostomella, Stenopora Lonsdale, Aniso-
trypa, Bythopora Miller and Dyer, Callotrypa Hall, and Leio-
clema almost seem an incongruous assemblage, yet after a very
careful comparison, I do not see how they are to be kept separate.
Being intermediate in its construction, Batostomella, is selected
as the type of the family. From that genus we can trace easy
gradations into Callotrypa, through Bythopora. On the other
hand Batostomella nitida, from the Chester group, is not at
all far removed from good species of Stenopora, while again it
is easy to show a very decided affinity between Stenopora and
Anisotrypa. On account of the diverse structure of the different
genera comprised in the family, I have found much difficulty in
grasping the really significant characters of the group, and I
am not certain that they are all mentioned in the above brief
definition. Still I believe our present requirements are satis-
fied.

Comparing the BATOSTOMELLID.E with other families, I find,
first, that the Lower Silurian species of Batostomella are related

342 PALEONTOLOGY OF ILLINOIS.

to Homotrypa of the MONTICULIPORHLE; second, several species
of Stenopora to the AMPLEXOPORIDJE ; and, third, several other
species of Stenopora and Anisotrypa to the RHABDOMESONTID.E
of Vine. The last comparison, if complete and thorough, es-
tablishes a close chain of connecting links between the TREPO-
STOMATA and CYRPTOSTOMATA.

(6) AMPLEXOPORID.E.— The zoarium in this group, comprising
the genera Amplexopora, Monotrypella, Petalotrypa, Lepto-
trypa, Atactopora and Discotrypa, may be ramose, bifoliate,
encrusting, massive or discoidal. The zocecial characters are
more simple than in any other family of the suborder, the
colony being composed of subequal, usually thin-walled, pris-
matic tubes, crossed by variously disposed horizontal dia-
phragms. The divisional line between adjoining zocecia is
generally distinctly marked, and in a few cases, (e. g. Mono-
try pella crassimuralis) the zocecia become rounded near surface,
leaving triangular tabulated interspaces, that closely simulate
mesopores in vertical sections. True mesopores are, however,
wanting, but small abortive cells, usually filled internally by a
calcareous deposit, sometimes occur among the zooecia forming
the monticules. Acanthopores are absent in Discotrypa, but
in the other genera they are more or less abundant and some-
times conspicuous.

On account of the simplicity of construction, we are forced to
depend very largely upon zoarial variations in dividing the
family into generic groups, Of microscopic characters the pres-
ence or absence of acanthopores is of the first importance in
distinguishing the genera.

(7) DIPLOTRYPID^E. This family is proposed provisionally
for the reception of Diplotrypa, Batostoma and Monotrypa,
three genera that have given me no little trouble to place
satisfactorily. Though fully persuaded that their association
in one family is natural, I am still not prepared to discuss
their inter-relations and affinities with other Bryozoa.

(8) CERAMOPORID^. In the typical genera of this family the
zoaria form thin parasitic expansions, but other modes of

BRYOZOA. 343

growth are frequent. Thus, in Crepipora, lamellate, discoidal,
and massive species occur, while a ramose zoarium character-
izes species of Diamesopora. The bifoliate and frondescent styles
of growth are also met with. The zocecia usually form short
tubes, but in Crepipora, Anolotichia and Chiloporella, they
are much longer and occasionally traversed by a small number
of diaphragms. A complete peristome sometimes surrounds
their apertures, but in most cases, only the posterior margin
projects. The lunarium. which is situated on this side, is nearly
always easily recognized, being of a decidedly lighter color in
sections than the rest of the zooecial investment. The irregu-
larly laminated construction of the walls, which appear also to
have been minutely porous, is the most striking, as well as, the
most constant character. The irregularity of the mesopores
and the absence of diphragms in them are other features that
aid in distinguishing this peculiar family of Silurian Bryozoa.
The affinities of the family are clearly with the FISTULIPORIDJE,
and the superficial resemblance between, for instance, (eramo-
porella and Eridopora is very marked, yet the internal char-
acters above mentioned are so constant and distinctive that
they demand recognition.

(9) FISTULIPORID.E. — In this large and important family the
zoarium varies greatly, but the massive and laminar with a
rugosely wrinkled epitheca on the under side, are the common-
est forms. Bifoliate and ramose species are less frequently met
with. The zooecia too vary considerably in the form of the
aperture, but in a majority of cases it is sub-oval, or sub-trian-
gular. In other cases the sub-pyriform or circular aperture
may prevail. Usually the apertures appear oblique, the degree
of obliquity being largely governed by the relative prominence
of the lunarium or hood. When they appear direct, the lunar-
ium is as a rule obsolete. Diaphragms are rarely numerous
being in most cases almost absent. In the perfect and mature
condition the interspaces always seem solid at the surface and
frequently granulose. Thin sections, however, show that the
zooecia are always separated from each other by from one to
three rows of vesicular cells, which, near the surface of mature
examples, are nearly or quite filled by a deposit of vertically

344 PALAEONTOLOGY OF ILLINOIS.

lined calcareous material. The vesicles generally decrease in
height outward, and, at least partially, already separated the
zocecia at their origin. True acanthopores and cystiphragms
never or only rarely occur, but certain peculiar spines of Li-
chenotrypa, cavernosa Nich, very much resemble the first. It also
appears that in the perfect state the zooecia apertures are cov-
ered by eccentrically perforated closures, and the perforation
itself seems at last to have been closed by a knob-like stopper.

In all, ten Palaeozoic genera are included in this family, two
of them, Pinacotrypa Ulrich, and Botryllopora Nich., with
some doubt. As the student will perceive by referring to the
sub-joined synopsis of classification, each genus is distinguished
from the other by certain zooecial as well as zoarial peculiarities.

A monographical study of the FISTULIPORID.E is very much
needed, and till the numerous and diverse forms of this exceed-
ingly difficult family have been subjected to a thorough investi-
gation, it will be utterly impossible to arrive at any satisfactory
conclusion with regard to the limits and really distinctive
peculiarities of the several generic groups now regarded as com-
prising the family.

IV. CRYPTOSTOMATA:* — In the typical section of this sub-order
the zoarium is bifoliate, consisting of two thin layers of zooecia
that have grown together back to back into ramose or foliar
expansions. In other groups the zoaria form fenestrated expan-
sions, consisting of only a single layer of cells, the reverse being
covered by a dense layer of striated or minutely granulose

This suborder was proposed in 1883, by M. G. B. Vine, in his 4th report to the Brit.
ASFOC. on fossil Polyzoa. His Ptilodictya lonsdalei, which seems to belong to Phceno-
pora Hall, rather than to Ptilodictya of Lonsdale, is regarded as the type of the sub-
order, but his idea of the true relation and the extent of the proposed division must
have been vague, for he places here only the five geneia Ptilodictya, Arcanopora
(Cystodictya), Glauconome (Vine, non auct.), Stictoporella and Rhabdomeson, while the
FENESTELLED.E and ACANTHOCLADIID.S: and other allied Bryozoa are left with the Cyclosto-
mata. In "Notes of Joredale Polyzoa of North Lancashire," 1885, he increases the list
of genera to nine by the addition of Rhomlopora Meek, Hyphasmopora E. Ethridge
jun., Streblotrypa Ulrich, and Goniocladia E. Eth. jr. In my "Am. Pal. Bry.," I placed the
PTrLODicTYONiD-s; as th<i first family of the TEEPOSTOMATA, immediately following the

FENESTELLID.33, ACANTHOCLADIID^ and ABTHROSTYLID.E (ARTHBONEMID.K) which W6r6

arranged at the end of the CYCLOSTOMATA. Now, recognizing Mr. Vine's suborder,
those three families and the PTILODICTYONID.E and STICTOPORID.S;, as there arranged,
go to form the bulk of the CBYPTOSTOMATA as here understood.

BRYOZOA. 345

sclerenchyma. In the remaining sections the zoaria are ramose,
with the zocecia arising from a real or imaginary axis and
opening on all sides of the cylindrical stems. Usually the zoaria
are continuous; but in some of the bifoliate and ramose forms
they are composed of a greater or smaller number of segments.
The variations in the form of the primitive cell suggest a rough
division of the suborder into three sections. In the first, con-
taining only the CYSTODICTYONID.E, the cell is semi-cordate or
obovate-acuminate in outline; in the second, comprising the
PTILODICTYONID .E. STICTOPORHXE, FENESTELLIIXE and ACANTHOCLA-
DIIIKE, it is oblong quadrate, hexagonal or rhomboidal; the
third section, to which the PHYLLOPORINID.E, ARTHROSTYLID.E and
RHABDOMESONTID.E belong, is distinguished by the tubular form
of the primar}* cell. In this respect several members of the third
section make a close approach to the TREPOSTOMATA.

All positive evidence goes to show that the primitive cell of
the CRYPTOSTOMATA corresponds to the entire zooecium of the
ordinary CHILOSTOMATA. The only ground upon which the
new suborder can be distinguished from Busk's well estabh'shed
division is the production of the primary orifice into a tubular
shaft ("vestibule"). Whether this will be regarded as a suffi-
cient reason for the separation of these Bryozoa into two equal
divisions, may be well questioned, since several genera now
classed with the CHILOSTOMATA (e. g. Steganopora and Distega-
nopora of d' Orbigny. and SteganoporeUa of Sinitt) exhibit practi-
cally the same peculiarity. Provisionally at least, it seems
desirable to hold them as distinct, because the feature pertains
to such a large number of Palaeozoic Bryozoa, which have re-
ceived through it a decidedly different aspect from that ex-
pected of CHILOSTOMATA. The fact that the peculiarity is so
rare in secondary and more recent ages, in which the true CHI-
LOSTOMATA are so abundant, also argues strongly in favor of the
separation by allowing us to assume that such genera asStegano-
pora are only the remnants of an extinct Palaeozoic type of
structure.

In a large proportion of the CRYPTOSTOMATA the primitive

aperture is marked by the development of an incomplete plate

which extends downward and forward from the posterior side

of the base of the vestibule into the primitive or true cell. This

-43

346 PALEONTOLOGY OF ILLINOIS.

I have termed the superior hemiseptum. The inferior hemisep-
tum is less frequently met with. When present it springs from
the bottom of the cell or from near the base of the anterior
wall. The disposition of parts will be better understood by
referring to the diagrammatic section of the cryptostomatous cell
given in fig. 9(p. 330); see also fig. 10 (p. 351), and, on plate LV,
figures 7 and 8: The vestibule is the cylindrical portion of the cav-
ity that is included between the external aperture and the super-
ior hemiseptum. The latter is best developed in forms having a
sloping area around the external orifice, yet, even among these,
(e. g. Stictoporella, fig. 13,) it may be quite obsolete or entirely
unrecognizable. When the external aperture is surrounded by a
peristome the superior hemiseptum is nearly always wanting,
but the inferior may be present.

The material which I propose to arrange under this suborder
is divided into eleven families, comprising together seventy or
more genera, — some of them very prolific. The PTILODICTYONID^E
may be regarded as the most typical.

(1) CYSTODICTYONHLE: — In this family the zoaria are composed
of two or three layers of cells, that grew together back to back,
forming by their union either bifoliate expansions or triangular
branches, the particular zoarial habit assumed by the various
genera being very constant. The margins are non-poriferous
and finely granulo-striate, while the zocecial apertures over the
basal portions become gradually covered by the same kind of
calcareous deposit. The form of the primitive cell is probably
the most distinctive feature of the family, being semi-cordate or
obovate-acuminate in outline, both forms being found in the
same example. They are always arranged in longitudinal series,
between vertical plates, usually alternating and, either entirely
separated from each other, or in contact at only limited por-
tions of their circumference, the intermediate spaces being
occupied by vesicles. The primitive orifice was terminal, of
sub-circular form and somewhat eccentric, while the front of the
cell Avas slightly convex, and appears to have been minutely
punctured (fig. 8,d). As growth proceeded the orifice was drawn
out into a tubular vestibule, and the spaces between the aper-
tures, keeping pace with the development, were filled by vesi-
cular tissue. Just below the surface of mature examples this
tissue was itself more or less completely filled by a calcareous

BRYOZOA. 347

deposit. Here the vertical plates between which the primitive
cells are arranged are also obsolete, although they may still be
represented at the surface by ridge-like elevations. A complete
peristome usually surrounds the superficial aperture, but some-
times the lunarial side only is elevated. A peculiar feature
about the lunarium is that it is always directed away from the
non-poriferous margins.

In internal structure and zocecial characters the various
forms of this family show great uniformity, so that we are
forced to rely almost solely upon zoarial peculiarities in draw-
ing the generic divisions. Fortunately these are very constant,
and, being conspicuous, readily serve the purpose of classifica-
tion.

The affinities of the family are with the FISTULIPORID.E on the
one hand and the STICTOPORID.E on the other. Pachydictya, has
all the characters of the CYSTODICTYONID,E, excepting the luna-
rium, and it seems highly probable that they had a common
origin. The FISTULIPORID.E, however, approach closest in their
later representatives (e. g. Meekopora), a fact apparently indi-
cating that the agreement is due to the moulding influences of
surrounding conditions rather than to ancestral relationship.*

(2) STicTOPORir.E: — The bifoliate zoaria of this important
family formed compressed, dichotomously dividing, continuous
or segmented branches, or palmate or leaf-like expansions. The
primitive cell is subquadrate, and with or without superior
hemiseptum. The inferior hemiseptum and mesopores are ap-
parently always absent, but vesicular tissue is sometimes pre-
sent. The median tubuli between the divisional laminae are
probably to be regarded as the most important peculiarity of
the family, though their true nature and functions have not yet
been determined satisfactorily. Likewise the granular termina-
tions of the vertical tubuli, (which I believe to have communi-
cated with those between the median laminae and to have
formed part of a system of communication between the pri-
mary cells and the external surface,) are more or less conspicu-

* Many instances might be mentioned to show that like surroundings are apt to
produce similar variations in really widely different organisms. For instance, in the
Cincinnati group at Delafleld, Wis., where mouticuliferous TBEPOSTOMATA prevail, several
species occur that are represented by nearly smooth forms in the Ohio exposures of
the same formation. At the Ohio localities the mammulated forms are comparatively
less abundant.

348 PALEONTOLOGY OF ILLINOIS.

ous features of tangential sections, and, when the same is suffi-
ciently well preserved, of the surface. The superficial aperture
is sometimes circular, but usually of a broad elliptical form,
and surrounded by a narrow sloping area, wanting in Pachy-
dictyae, where it is replaced by a faint peristome.

The family as now restricted comprises the following six
genera: Stictopora Hall, Eurydictya, Dicranopora, Pachy-
dictya, Phyllodictya and Euspilopora Ulrich. The first three
are distinguished by zoarial differences, the remainder by slight
zocecial modifications as well. I find that Pachydictya ap-
proaches the CYSTODICTYONID^E in having vesicular tissue, the
anterior end of the primitive cell sometimes rounded, and a
slight peristome around the superficial aperture. Opposed to
these points of resemblance is the absence of the lunarium, the
presence of median tubuli, and the fact that the prevailing
form of the primitive cell is often either sub-quadrate or hexa-
gonal. The chain of evidence showing the relation of the genus
to Stictopora* and Eurydictya is completely established through
the intermediate species Pachydictya splendens and P. firm a
Compared with the PTILODICTYONID.E we find a general agree-
ment in the arrangement of parts, but a closer examination
will reveal important differences. Of these the absence of
median tubuli among the genera of that family, alone need be
mentioned here.

(3) PTILODICTYONID.E: — Bifoliate zoaria, continuous or jointed,
forming leaf-like expansions or compressed branching stems;
thus having the same range of zoarial characters as the CYSTO-
DICTYONID^E and STICTOPORHLE. The outline of the primitive cell
is oblong hexagonal or quadrate, or rhomboidal. In the typical
genera both the inferior and superior hemisepta are well devel-
oped, but in other divisions either one or both are apparently
wanting. In old examples of Ptilodictya they may be repre-
sented at successive levels, so as to simulate diaphragms (see
fig. 6 and 11). Vestibular portion of zooecia with thick walls,
the central region between the cavities being usually also of
conspicuously lighter or darker color than the rest. In typical
forms this region is transversely lined and margined on each

*Kegarding Stictopora fenestrata as the type of the genus. If, however, 8. ele-
gantula is insisted upon as the type, then;the reader will please read lihinidictya Ulrich,
where I have written Ktictopora Hall.

BRYOZOA. 349

side by two close rows of exceedingly minute dots (see fig. 2ft).
Untabulated mesopores occur frequently, but in no case known,
vesicular tissue. The following genera are placed here: Ptilo-
dictya Lonsdale, Clathropora Hall, Tseniodictya, Phzenopora
Hall, Ptilotrypa, Graptodictya, Artbropora, Stictoporella, In-
trapora Hall, and Stictotrypa. Of these, the first, second and
third are distinguished mainly upon constant zoarial peculiari-
ties; the fourth has two mesopores occupying the transverse
space between the ends of the zooecia apertures; the fifth, very
oblique apertures and a small accessory cell in front; the sixth
and seventh have a filiform peristome and vermicular striae on
the interspaces; the eighth has more or less numerous meso-
pores, very thick-walled tubular zooecia, with dilating apertures,
and no hemisepta; the ninth also has numerous mesopores, but
thinner walled zooecia, with quite an abrupt aperture and an
inferior hemiseptum; the tenth has a decided peristome. The sys-
tematic position of the last (Stictotrypa) is somewhat doubtful.
(4) FEXESTELLID-E: — This very characteristic Palaeozoic group
of Bryozoa presents us with an almost endless array of beauti-
ful forms, whose delicate net-work generally affords us proof of
the exceeding constancy with which, what may appear to the
uninitiated as very trivial zoarial features, recur in species after
species. The exceeding abundance of specific modification causes
a continual effacenient of sharp divisional lines, and I know of
no group better calculated to show that such do not occur in
nature. On the contrary, the more our investigations are ex-
tended, the more evident it becomes that our classifications are
necessarily largely based upon arbitrary divisions. Obviously
then, that classification is the best which offers the most con-
venient and at the same time the most natural (genealogical)
arrangement possible, a desire not by any means easily realized.
In my subdivision of the family I have been guided by the test,
that the value of a character is determined by its degree of
prevalence. Accordingly, when I have found a number of species
that agreed in one or more features without disagreement in
others known to have greater importance, I have regarded them
as entitled to recognition as a separate genus. Subgeneric di-
visions, being both inconvenient and useless, I am opposed to,
and have not adopted them excepting in such cases where they
seem to merit generic distinction.

350 PALEONTOLOGY OF ILLINOIS.

With the single exception of Thamniscus, in which the
branches are usually free, the zoaria of this family form reticu-
lated expansions of which only one side is celluliferous, the
other being finely granulo-striate. Commonly, the branches are
more or less rigid and united to each other by solid processes,
which are developed at such regular intervals that their num-
ber in a given space affords a good test in the discrimination
of species. In other cases the branches are sinuous and united
by anastomosis. The fenestrules vary from circular to acutely
elliptical, but when the dissepiments are thin, a quadrate form
prevails. The primitive cell, or true home of the polyp, is either
oblong quadrate or hexagonal, or rhomboidal, and never com-
mences, as claimed by Waagen and Pichl, (Pal. Indica, ser.
XIII, Salt Range Foss. p. 772) "in a long thin point." On the
contrary, in all cases when the cell is not of rhombic form, the
proximal end is truncated, being, furthermore, vertically parallel
with the anterior wall. As seen in longitudinal sections, the
cell is directed more or less obliquely upward and forward, the
angle of divergence from the basal plate varying between the
extremes of 45° and 90°. Generally the height of the cell is
considerably less than its length, yet in a few instances the two
dimensions are almost equal. The inferior hemiseptum is often
present, and springs (apparently always) from the anterior
wall near its base. Sometimes it is so strong that in deep
tangential sections (PI. LV, fig. 7) the cell appears as though
divided into two apartments.

Another peculiarity that may be seen in a tangential section
of almost any Fenestellid (see figures on PL LIV and LV), is
due to the presence of a superior hemiseptum. Namely, at op-
posite points on the sides of a cell through which the sect on
passes, just beneath the level of the primary orifice, the wall is
more or less sharply bent in, the inflections being in some cases
sufficiently extended to unite, so as to separate an anterior
subcircular space from the remaining posterior portion of the
cell. Generally, however, the inflection appears strongest on
the upper side (especially in Fenestella) giving to the cell a
rather marked kidney-form outline (see PI. LI, fig. 5a, and PI.
LIV, fig. 5). This appearance is not due to a greater develop-
ment of the internal ridge on the outer side, but to the obliquity

BRYOZOA.

351

with which the tangential section necessarily passes through
the somewhat laterally directed cells. This is shown in Poly-
porn, where the inflections on each side are about equal in the
central row or rows of cells, while in those of the marginal rows,
which are directed laterally, they appear unequal as in Fene-
stelki and other genera having only two ranges of zooecia (see
PI. LY. fig. 4). The superior hemiseptum, to which these inflec-
tions are due, forms a ridge-like thickening on the inner side
of the cell, which becomes obsolete, or nearly so, toward the
center of the posterior side of the primary aperture, and en-
tirely so at about the middle of the vertical sides, being strong-
est in the region of the angle, formed by the union of the lat-
eral walls and the slightly convex front or top of the cell. The
accompanying digrams will probably serve better to show the
peculiarities in question than any verbal explanation.

This peculiar feature
(whose functions unless
it acted as a support to
the cell front, is unknown)
was noticed in 1878 by
Mr. A. W. Waters and
described and figured by
him in the transactions
of the Manchester Geol.

Fig. 10. Diagrams illustrating the different ap- ^OC. for that year, also

pearances presented in thin sections by the zoce- |)y ^{r John Young who

cium of a Fenestellid having both hemisepta. a and .,«*,•, r< i a

b. side and end sectional views of the zooecium crossed in the Trans, (reol. SoC.

by five dotted lines, a, b, c, d and e. Drawings a", b", * fMa«soY\tr fr>r- 1 «7Q

c", d" and e" represent the zocecial cavity as it ap- ( ° ' y'

pears in tangential sections at levels corresponding gives a short description

to the dotted lines, c, represents a "nest" of the , . „,, .

outlines. °f ^- The former found

two identations but the latter failed to notice that the appar-
ent inflection on the one side of the cell of species of Fenestella
is caused by the slight lateral direction of these walls in such
form.*

d'

* In this connection it seems proper to show how imperfect observations of certain
defective specimens have led the Messrs. Young and Young into an error, which ap-
pears not only to have been overlooked by Mr. Vine, but induced him to propose a new
family for the sub-generic division proposed by those authors. In 1875 they publif l:ed a

352 PALAEONTOLOGY OF ILLINOIS.

The primary orifice is of sub-circular form, somewhat nar-
rower than the width of the cell, and occupies the anterior
third (or a little more) of its length. As growth proceeded the
front of the cell was gradually thickened by a deposit of lami-
nated sclerenchyma ; this calcareous addition being built up
about the orifice so as to draw it out into a vertical tubular
shaft, called the "vestibule" by Mr. Vine. The superficial aper-
ture is circular, and, with few exceptions, surrounded by a peri-
stome.

In transverse sections of the branches the original basal or
germinal plate is generally quite distinct from the subsequently
added layers of calcareous tissue. A number are figured on
plates LIV and LY, that show how sharply the plate is often dis-
tinguished. Almost invariably the lower side of the plate pre-
sents a number of tooth-like projections that represent transverse
sections of former longitudinal striations. It is a fact that the
reverse of many Fenestellids show strong striae on very young
examples, which are wanting or nearly obsolete on old specimens.

description and figures of Glauconome marginalis, for which they proposed the new
subgenus Diplopora, upon the ground that there is a small secondary pore immedi-
ately beneath the true apertme. Similar secondary pores they mentioned as oc-
curring in their Glauconome (Acanthopora) stellipora and Fenestella (Actinostoma)
fenestrata. This secondary pore I consider the result of attrition combined with
a paucity of calcareous secretion by the zooids. The Messrs. Young and Young
show in their figure of the first that the supposed pore varies much in size, and rightly
attribute the variation to the state of preservation. Had they investigated a little far-
ther, I think they would have seen that there is a good reason for the presence of the
"pore" in their species. These (especially D. marginalis) are forms in which the de-
posit of cal areous material over the primitive cell was much less than usual. Polypora
whitei and var. sevillensis are likewise such forms, and, as will be seen from fig. Ib
and 2 on plate LXII, frequently present what Waters suggests might be compared with
the suboral pore found in so many CHILOSTOMATA. I am really sorry that I flnd it so
often necessary to differ with my esteemed English collaborers in this difficult branch
of palseozoology. Indeed, in this instance I am particularly grieved, since it would have
pleased me much to be able to corroborate so important a point for comparison be-
tween Pateozoic and Recent Bryozoa. But, being convinced that their conclusion is
based upon defective specimens, I must dissent.

Comparing examples of the several species in question with shallow tangential sec-
tions of ordinary Fenestellids we find that with a little diagrammatic restoration of the
section, there is no essential difference, while the supposed "pore" is explained by the
wearing away of the thin and slightly convex1 portion of the front of the cell. The dark
matrix which has entered the cell is then clearly seen, and the weathered portion might
readily be mistaken for a suboral pore. The thin septum which is said to separate the
lower from the true aperture is nothing more or less than the superior hemiseptum,
and when the attrition has proceeded to the extent that even this is removed then the
general appearance of the cell with its two inflections looks precisely like what we see
in tangential sections of most FENESTELLIDS.

BRYOZOA. 353

All the dense portions of the zoarium, such as the base, the
spiral axis of Archimedes, and diverging supports of Lyropora,
a< well as the stony deposit over the front and reverse of the
zooecia exhibit essentially the same structure. A finely lami-
nated composition prevails throughout, and very delicate ver-
tical tubuli, penetrating the laminae, can, as a rule, be demon-
strated. The tubuli again are generally arranged in series, and
though varying in number are always abundant.

A- regards zoarial features the genera Semicoscinium Prout,
Isotrypa and Unitrypa Hall, and Hemitrypa Phillips, present
several peculiarities that have at various times been called into
question. The most serious objection to Hemitrypa, which was
the only genus of the group generally known, comes from Eng-
lish palaeontologists. In a paper entitled "A Review of the
British Carboniferous Fenestellidav' published in the Quart.
Jour. Geol. Soc. for May. 1879, Mr. G. W. Shrubsole. after
quoting some remarks by Lonsdale upon the genus, writes as
follows: "There can be no doubt that the interior portion of
the Hemitrypa hiheruica (McCoy), is a Fenestella > nor need we
be in any doubt as to the species. The difficulty has always
been the external sheath. It is important to mention that the
same form is parasitic on brachiopods and crinoids, as well as
Fenestella. Its connection therefore with Fenestella is accidental
and not structural. It is without doubt a small coral common
to the limestone, very similar to Flustrx palmata McCoy, the
empty calices of which cover over and conceal the Fenestella
underneath. Hemitrypa, as we have seen, has Fenestella mem-
branacea Phillips for the ground work, and a microscopic
coral or polyzoon for the super-structure/' The next year in
reviewing the Upper Silurian species of Fenestella. he treates of
specimens of F. prisca, Lonsdale, which "are disfigured by the
enveloping coral." This species most probably belongs to Uni-
trypa. ''The growth of F. prisca is readily detected by the
peculiar shape of the so-called fenestrules which are often twice
as broad as long. What I take to be the tabulae (!) of the
coral occur more frequently than the dissepiments of the Fenes-
tella." As regards Mr. S. R. Vine's stand-point it is enough to
say he appears to have accepted Mr. Shrubsole's ultimatum

without examining into the facts for himself.
—44

354 PALAEONTOLOGY OF ILLINOIS.

When I think of the hundreds of exquisitely preserved examples
of species of the genera in question that I have seen and
studied, it seems almost ridiculous that argument is necessary
to show them to be a structural unity and not composed of
two separate and distinct organisms. It seems to me that Mr.
Shrubsole must be lacking sadly in caution, as well as in respect
for the work of others, or he would not express himself so
dogmatically as in the above samples upon a question that
manifestly he can scarcely have touched. Both Mr. Shrubsole
and Mr. Vine could easily have verified the structural unity of
the Fenestella interior and the supposed parasitic coral by mak-
ing a few judicious thin sections of specimens preserved in lime-
stone, those in shale being usually so much compressed that the
union between the two fenestrated expansions is broken. Had
they had an opportunity of examining some of the silicified spec-
imens from the Falls of the Ohio river, which show the delicate
net-work perfectly free from the matrix, I am sure their present
views upon Hemitrypa and Unitrypa would never have been
published. Still, as the outer structure of Hemitrypa, etc., is
by many regarded as of the nature of a parasite, some refuta-
tion is required. I will therefore ask a few questions.

If the structure is viewed as a parasitic bryozoan similar to
Paleschara Hall, or to Monticuliporoids of the type of Lepto
trypa, upon what grounds is the supposition based? The
zooecium of a bryozoan raust before all things have a bottom
or basal plate. Is this present on the inner side of the external
net-work? I answer emphatically, no. On the contrary the
little openings communicate without any interruption with the
interior space between the two expansions. It is true, of course,
that over the basal portion of old examples of Hemitrypa and
Unitrypa, the fenestrules on both surfaces of the zoarium are
covered by a thin calcareous membrane, but this fact has no
bearing whatever upon the question. Again, if the suspected
expansion is of the nature of Leptotrypa, why do we not find
clusters of large cells, which are invariably present in such
forms? And why do the little openings in the superficial net-
work of Hemitrypa correspond so exactly both in position and
number with the zocecial apertures beneath them in the cellu-
liferous expansion? Surely this is not simply a coincidence.

BRYOZOA. 355

Further, why is it impossible to detect a divisional line between
the supposed parasite and the "disfigured"' Feuestella? Upon
what ground does Mr. Shrubsole base his assertion that the
same parasite is found upon brachiopods and crinoids? In this
country it is less erratic, besides being an exceedingly- constant
type, Hewitrypa fenestellids ranging from the Upper Silurian
to the Carboniferous. Lastly if the cross bars of Unit ry pa. are,
as claimed by Mr. Shrubsole, the tabulae of a coral, will he not
oblige us by publishing a description of the unique form? But
let us pass on to something more interesting than this rather
impertinent inquisition.

In Semicoscinium we have a type that commenced already, in
the Niagara group, with such aberrant forms of Fenestella as
F. tenuiceps and F. acmea. In all its representatives the keel is
very high, while, especially in the more typical forms, the
branches are not rigid on the reverse side of the zoarium but
appear to inosculate. The zoarium is funnel-shaped, with the
upper portion more or less undulated and often decumbent.
The poriferous side is the outer one, and the strong keels of the
branches give this surface a vertically lined appearance. The
base of the funnel, particularly in old examples, is smooth and
spreads somewhat over the body to which it is attached. The
smoothness is due to a thin membrane which is spread over
the keels sometimes a considerable distance up the side of the
inverted cone, the space between the keels and under the mem-
brane being filled with vesicular tissue. The keels themselves
are very thin immediately above the top of the branches, but
are much thickened towards the summit, which in some cases
is quite flat, but in others varies from obtusely to acutely
ridge-shaped. The sides of the flattened keel summit is usually
smooth, but in some they are crenulated (S. planodorsatum
Ulrich. PL 44, fig. 3). By producing these crenulations into
transverse connecting bars, we realize through certain interme-
diate species (e. g. Fenestella ? precursor Hall, and F. bigeneris
Ulr.) what Hall has described as Unitrypa. The transverse
bars that characterize this genus are really vertical plates \\hich
occur at very regular intervals (corresponding to the zooecia)
and are usually, if not always, suddenly bent backward, so as
to give the intervening spaces the appearance of imbricating

356 PALAEONTOLOGY OF ILLINOIS.

cell mouths. In Isotrypa Hall we have the same general con-
struction as in Unitrypa, but the external aspect of the two
expansions are so much alike, that it is sometimes difficult to
distinguish between them. Indeed, the summits of the keels and
the connecting bars are rounded and longitudinally striated, so
that they might readily be mistaken for the reverse side of an
ordinary species of Fenestella. Sections of a species of this
genus are figured on plate LIV.

In the much disputed Hemitrypa, we find a somewhat differ-
ent construction. In this genus the carina (which in Semico-
scinium, Unitrypa and Isotrypa is a continuous plate) carries a
close series of small pillars that support the favose super-
structure. A regular series of arches connect the pillars and
combine to form a longitudinal crest at intervals corresponding
to the number of zocecia. Short transverse bars proceed from
each side of this crest and extend to the center of the space
between two branches where they unite with a false crest which
is usually somewhat thinner and more decidedly zigzag than
the true crest. This arrangement of the bars and crests pro-
duces a delicate net- work, pierced by small and exceedingly
regular hexagonal, petaloid, or circular openings, This brief
description of the structure of Hemitrypa may be advantage-
ously supplemented by a study of the sections figured on plates
LIV and LVII. None of these are in any way diagrammatic
but are drawn as near to nature as possible.

The free condition of the branches in species of Thamniscus in-
duced King to establish another family for their reception.* In
this course he is followed by Vinef and by Waagen and Pichl$.
Zittel, however, places the genus as a synonym under Acantho-
cladia King§, being under the erroneous impression that the
two genera are distinguished only by differences in the arrange-
ment of the zooecia apertures. All of these authors agree in

* Mono. Perm. Foss. (Pal. Soc. Pub. vol. Ill, 1849.)

t 4th Kept. Brit. Assoc. on Foss. Poly. 1883 and Notes on Joredale Poly, of N. Lan-
cashire, 1885.

+ Palseontologica Indica, ser. XIII, part 5, 1885.
§ Handbueh der Pal. 1880.

BRYOZOA. 357

placing Acanthocladia in the immediate vicinity. My arrange-
ment is quite different. I find that there exists between Tham-
niscus and Polypora a very close chain of intermediate links.
Examples of T. dubius (the type of the genus) now before me,
clearly show that non-poriferous dissepiments occasionally con-
nect the branches. In cell structure there is no difference be-
tween T. dubius and such species of Polypora, as P. tubercu-
lata Prout, P. cestriensis and P. spinulifera. In species of
Thamniscus the branches bifurcate in precisely the same man-
ner, though as a rule more frequently than they do in Poly-
pora. Such a slight difference can, of course, scarcely be taken
into account as of even generic importance. Now as to the
presence or absence of dissepiments, we must, because of their
constant development in so many forms, regard them as a
character of considerable value. But here again the ''vanishing
lines of nature" come into play, giving us an inkling of geneo-
logical relation. For instance, in Polypora halliana Prout, we
have a true species of the genus, but upon comparison, it is
found that the species is closely related to P. maccoyana, and
this to P. distinct a and P. gracilis (Prout.) The last is brought
into close relation with Thanmiscus divaricans by an unde-
scribed form from the Keokuk group of Keutucky. In P. halliana
and P. maccoyana there are from two to six dissepiments to
each bifurcation, in P. distincta and P. gracilis, generally two,
while in T. divaricans there are rarely two, generally one, and
sometimes none. The same mav be said of T. ramulosa*

* T. ramulosa belongs to another line of development tending the same way through
P. cestriensis and P. tubercitlata. It is my opinion, and good evidence can be brought
to support it, that the majority of the Carboniferous and Permian species of Thamni-
sc»s (including the type species) were developed from Devonian and early Carboniferous
species of Polypora, such as I have mentioned, and not from Silurian and Devonian
species now referred to Thamniscus. When it comes to the latter, we have but little
evidence to show that they were derived from Polypora, yet the inference is fair
that they were, and that Polypora always had within itself the tendency to assume the
characters of Thamniscus. If this is admitted then we can admit that Fenestella also
had a continual tendency to run into Polypora. Again many problems present them-
selves which can only be explained by supposing that the changed form reverted back
into the parent stem. (A Fenestella gradually assumed the characters of Polupora and
vice versa). Hence, in all formations from the Niagara to the Coal Measures, there were
intermediate forms between Polypora and Fenestella. These species, the evidence leads
me to believe, were more often derived from typical species of the genera than from
each other.

358 PALEONTOLOGY OF ILLINOIS.

From whatever point the question may be viewed, no one can
deny the relation between the genera as here outlined. As re-
gards the relation generally supposed to exist between Acantho-
cladia and Thamniscus, my investigations have convinced me
that it has no real foundation in nature. That the branches in
the two genera are free is of little consequence, since there are
differences of far greater import. In fact, Acanthocladia is con-
structed upon the same plan as Pinnatopora Vine (Glauconome
of authors), Synocladia King, and Septopora Prout. In these
four genera comprising the bulk of the ACANTHOCLADIIDJE, as
here denned, the zoarium consists of primary and secondary
branches, the latter being smaller and arranged in a pinnate
manner on each side of the former. In the two first the second-
ary branches are never united, bnt in Synocladia and Septo-
pora, those which spring from adjacent primary branches coalesce
so as to produce a reticulated expansion.

As Mr. G. R. Vines arrangement of the Bryozoa under consid-
eration is quite different from that adopted by me, it is but
justice to the student that some mention be made of it. He
restricts the family FENESTELLID^E to fenest rated or non-fenes-
trated forms in wThich the zocecia are "arranged biserially in
the branch." The four genera Fenestella, Ptilopora McCoy,
Pinnatopora and Septopora, he groups under this head. The
new family DIPLOPORID^E he proposes for the reception of Diplo-
pora, Acanthopora and Actinostoma, three genera previously
proposed by Messrs. Young and Young as subgenera of Fenes-
tetta and Glauconome. For Polypora and Phyllopora King
he proposes the POLYPORID^E. Lastly, Kings family THAMNI-
SCID.E, containing Thamniscus, Acanthocladia and Ichthyorachis
McCoy, is accepted by him.

This classification is so obviously artificial that the proba-
bilities are very much against its acceptance by any one who
will undertake an extended study of the forms in question. His
definition of the FENESTELLID.E would include Phylloporina daw-
soni, and the Permian Phyllopora ehrenbergi since in both the
zocecia are arranged in two series. What would he do with
such forms as Polypora whitei, P. radialis, P. biserialis, P.
celsipora Hall, P. art a Hall, and P. incepta Hall? They would

BRYOZOA. 359

figure equally as well under his FENESTELLIDJE as under the POLY-
PORID.E. Lyropora Hall, would go partly in one family, and the
remainder in the other. And why separate Pinnatopora and
Septopora from AcantbocJadia and Ichthyorachis? Simply
because the former have only two rows of zooecia, and the lat-
ter three or more? Such a difference is surely not sufficient to
outweigh the important points of agreement above mentioned;
no, it does not require a very extended knowledge of the Fene-
stellids to become convinced of the inadequacy of variations in
the number of ranges of cells as foundations for families, yes,
scarcely even for genera. As to the three genera which he
groups under the name DIPLOPORID.E, I should say that Actino-
stoma is founded upon a species of Fenestella, in which the
radial ribs of the opercular closures of the zocecial orifice were
not obliterated by deposits of calcareous material. I have
seen these more or less distinctly preserved in a number of the
FEXESTELLID.E (species of Fenestella, Polypora, Lyropora and
Pinnatopora) and believe that they were generally present in
these Bryozoa. Acanthopora Y. & Y., stands in the same re-
lation to Pinnatopora* As regards Diplopora Y. & Y., I shall
view the division in the light of a valid genus, but not upon
the characters mentioned by Mr. Vine and the authors of the
genus. For discussion of this point see remarks upon the genus
further on. With regard to the POLYPORIU.E and THAMNISCIDJE,
nothing farther need be said, as my opinion of them is already
sufficiently expressed.

Waagen and PichPs arrangement of the FENESTELLID.E differs
somewhat from that proposed by Tine. They divide the family
into three sub-families, of which the first, the FEXESTELLIN.E, con-
tains, FenesteUa, Fenestralia Prout, Septopora, Lyropora,
Ptilopora McCoy, Helicopora Claypole, and Archimedes
Lesueur. In the POLYPORIN.E they propose to include Poly-
pora. Phyllopora, Synocladia and Dendricopora DeKoninck,

* The name Acanthopora has priority over Pinnatopora of Vine, having been pro-
posed in 1875, but as it is less appropriate than the latter and was erected upon what I
believe to be defective specimens, and only as a provisional subgenus under Glauco-
nome, it seems desirable to drop the name in favor of Vine's, which was well charac-
terized and established for the reception of species not intended to be covered by
Acanthopora,

360 PALEONTOLOGY OF ILLINOIS.

while for Goniocladia Ethridge and Ramipora Toula the sub-
family GONIOCLADINJE is erected.

This classification has as little, or even less merit than Vine's,
being based upon the presence or absence of a median keel, a
character shown by experience to be unreliable. All the genera
in the first and second divisions, excepting Septopora, Syno-
cladia, and, probably, Ptilopora and Dendricopora, belong to
the FENESTELLID.E as here defined, but Goniocladia is very differ-
ent, being related to the CYSTODICTYONID.E, where I would place
it provisionally. Ramipora is doubtful, and before its position
can be determined, must be subjected to recent methods of in-
vestigation.

The typical genera of this and the following family have
heretofore been regarded, I believe, universally, as CYCLOSTO-
MATA. This now seems to be a wrong collocation, resulting
from defective observation of certain deceptive peculiarities in
their structure. In the first place the zooecia have always been
described as tubular. This, however, is an error, as only the
vestibular prolongation of the orifice is tubular, the true ZOCB-
cium being an horizontal cell of quadrate or hexagonal form,
with both ends truncated. The aperture, furthermore, is not
situated at the end of a tubular zooecium as in the CYCLOSTO-
MATA, but occupies the anterior portion of the upper side
(front) of the cell; in short, the cell agrees in form with those
of the Escharine group of the CHILOSTOMATA, to the same ex-
tent as those of Ptilodictya and other genera referred to the
new sub-order CRYPTOSTOMATA. Vine, in briefly discussing the
subject, brings out another point in their structure, which he
compares to the foraminated condition of the walls of the
TUBULIPORHLE, namely, the minute tubuli which penetrate the
dense deposits of laminated sclerenchyma on both the front of
the zooecia and the basal plate on the reverse side of the
zoarium.

Admitting provisionally the propriety of the comparison, I
ask, will it not apply fully as well to the CHILOSTOMATA, since a
foraminated cell front is well known to be present in many
genera of the sub-order? Why should the answer not be yes,
and, if we take other points of structure into consideration,
better? My space being limited, I am not at liberty to enter

BRYOZOA. 361

into any extended discussion of this and other points bearing
upon the question,, but as it is an important one, I will men-
tion briefly some of uiy reasons for removing the families from
the CYCLOSTOMATA.

First, the zooecia of the FEXESTELLID.E and ACANTHOCLADIID.E
are not tubular, but agree closely in form and general structure
with those of the PTELODICTYOXID.E and ESCHARID.E.* Second,
the primary orifice is drawn out into a shaft-like vestibule, pre-
cisely as in typical members of Mr. Vine's new sub-order CRYP-
TOSTOMATA. Third, the structure of the secondary deposit over
the cells and basal plate, differs in no essential manner from
that of the dense tissue which forms the non-poriferous margins
aud pointed base of Ptilodictya. and the deposit over the basal
portions of the zoaria of many CYSTODICTYOXID.E. Fourth, one
or both of the structures that I have called superior and in-
ferior hemisepta are usually (perhaps always) present. These
four- reasons refer to such weighty points of structure that I
am content to rest the question upon them without detailed
explanation. The critical student can, without much labor,
corroborate at least some of the abundant evidence relating to
the points at issue given on the plates attached to this volume.

(5) ACANTHOCLADIID.E: — The minute structure of this family
is so much like that of the preceding, that for present needs it
is sufficient to point out the features upon which the family is
maintained.

The zoaria are generally pinnate, often fenestrated, and rarely
dendroid, differing from those of the FEXESTELLID.E in consisting
of primary and secondary branches, and in being without non-
poriferous dissepiments. The primary branches are strong
straight stems, which usually remain simple, but in a few cases
are known to bifurcate. The secondary branches are nearly
always considerably smaller than the primary ones, from the
two opposite margins of which they are given off. In Syno-
dadia and Septopora the secondary branches unite with those
of adjacent branches, thus forming reticulate expansions. From

* In a few species the secondary deposit upon the cells was very slight. These re-
semble Chilostomatous Bryozoa in a marked degree. In describing one of these forms
(Pinnatovora? simpler* Mr. Vine states (Notes on Yoredale Poly.) that it reminds one of
Chilostomatous rather than of Cyclostomatous Bryozoa.

-45

362 PALAEONTOLOGY OF ILLINOIS.

the margins of the primary branches new ones are given off at
the same angle as the secondary branchlets, and these again
are provided with branchlets the same as the original stem
(see PL LXVI, figs. 7 and 8).

From the above it will be seen that the ACANTHOCLADIID.E and
FENESTELLHLE are distinguished by a zoarial difference, but this
difference is merely the result of some peculiarity in the de-
velopment of the zooecia, causing celluliferous branchlets to
take the place of solid dissepiments. In Ptilopora McCoy,
which might with equal propriety be arranged with the FENE-
STELLID.E, we have intermediate conditions. It is a type that
commenced in early Devonian times with species of FenesteUa,
in which some of the branches were disproportionately thick-
ened, and the thinner branches at the same time arranged in
an indistinct pinnate manner. The type cannot rank as a sep-
arate family, and the ultimate position of the genus depends
largely upon the relative importance attached to the presence
of dissepiments on the one hand and the pinnate arrangement
of the zoarium on the other. (See remarks on the genus fur-
ther on).

(6) SPHRAGIOPORID.,E: — This family is proposed for the re-
ception of a single genus, of which, so far as I have seen, only
one or possibly two species are known. This is, however, so
distinct from all the previously established families, that I feel
justified in adopting the course here pursued. For particulars
relating to the structure of this unique bryozoan, the reader is
referred to the specific description further on.

(7) PHYLLOPORINHXE: — The genera comprised in this family
have been established upon species usually referred, heretofore,
to the FENESTELLID^E. A minute comparison of their interiors
having brought to light certain peculiarities in zooecial struc-
ture, a new family seems to be demanded for them. These dis-
tinctive features have already been pointed out in my general
remarks on classification, and to prevent repetition, the reader
is referred there, and to the descriptions in the subjoined synop-
sis of classification.

(8) ARTHROSTYLID.E.— This interesting family of Bryozoa,
especially in its typical members, reminds one of the recent
CELLARID.E, yet beyond the articulated zoarium and a general

BRYOZOA. 363

external resemblance, but little can be brought showing true
relationship. On the contrary, in the form of the zooecia there
is close agreement between them and the STICTOPORHLE. It also
appears highly probable that the ARTHROSTYLID.E constituted a
distinctively Silurian type, since no representatives are as yet
known from either the Devonian or Carboniferous systems.

The jointed condition of the zoarium is the most conspicuous
and perhaps also the most important feature of the family. It
is well shown in all the genera excepting Nematopora, in which
the zoarium is a dichotomously branching stem above the basal
articulating extremity. (PI. XXIX, fig. lla). In Helopora
Hall, Sceptropora Ulr., and Arthrostylus Ulr., the segments are
simple and terminally joined together. In Arthroclema Billings,
the zoarium forms a plumose expansion, and is divisible into
numerous primary, secondary and tertiary segments, those of
the first and second order being connected terminally and ranged
in straight lines. A deep socket occurs on two opposite sides
of each of the joints of the first and second series, in which the
first of the series of the second and the third order is inserted.

The zooecia are arranged in a radial manner around a central
axis, and, excepting Arthrostylus, open on all sides of the sub-
cylindrical segments. In the excepted genus one of the sides is
marked only with longitudinal striae. The primitive cell is
wedge-shaped, but inclined to be tubular in the larger species.
As nearly all of the zooecia commence at the center of the zoar-
ium the reason is obvious; their form must adapt itself to the
distance between the axis and the surfaces, and as it is greater
in the large species than in the smaller, the primitive cell ap-
pears, consequently, somewhat tubular (compare figs. 15 and
18) . Ordinarily they are oblong quadrate or hexagonal in out-
line, and aside from their wedge-like shape (due to their arrange-
ment) agree closely with those of the STICTOPORID.E. "Hemi-
septa" I have not observed.

(9) RHABDOMESONTID.E:— This interesting family must be re-
garded as forerunners of the VINCULARID^. Indeed the external
resemblance to species of that later type is often so very striking
that a real affinity between them is forcibly suggested. Minute
comparisons show, however, that the differences which distin-
guish the groups of Palaeozoic Bryozoa from their more recent

364 PALAEONTOLOGY OP ILLINOIS.

representatives also prevail in this case. Namely, the zocecia
are more tubular than those of the Vincularids, while the
secondary deposit which gave rise to the "vestibule" of the
CRYPTOSTOMATA is wanting in them. In other respects the closest
agreement can be shown. On the other hand the RHABDOME-
SONTID.E are intimately connected with the BATOSTOMELLID.E of
the TREPOSTOMATA, and it is sometimes very difficult to draw
the line between Rhombopora and the genera of that family.
The genus Rhombopora also embraces species that compare
very favorably with Streblotrypa. In fact the genus contains
some very diverse yet intimately related forms of which each
points in widely different directions.

In Rhabdomeson Y. and Y., the zocecia are arranged round an
axial tube precisely the same as in the cretaceous Siphonella of
Hagenow. Such an axis does not exist in Rhombopora nor
have I yet seen an American species of this family in which it
is present. The structure of the zooecia is about as follows:
Their primitive portion is always tubular and enclosed by ex-
ceedingly thin walls. Their proximal ends may be attached to
an axial tube (Rhabdomeson}, or they may originate along an
axial line around which they are wedged in a radial manner
(Rhombopora incrassata, PI. LXX, fig. 12d) or they are pro-
duced by germination throughout the axial region (R. suban-
nulata, PI. XLV, and R. tabulata and R. minor, PL LXX).
Here too the longer tubes may be intersected by one or more
complete diaphragms. These structures must not be confounded
with the hemisepta which are usually present at the point of
outward bending and thickening of the walls. As in PtUodidyn,
two or more pairs of hemisepta may be developed in old exam-
ples, but in most cases the inferior hemisepta appear to be
absent, (PI. XLV, fig. Ih, and PI. LXXI, fig. 3c). The aper-
ture is circular or elliptical and, with only few exceptions, sur-
rounded by a sloping area, typically rhombic or hexagonal in
outline, causing the inter-apertural space to be ridge-shaped.
The summit of the ridge carries from one to three series of
minute granules, while an acanthopore is commonly found at
the angles of junction.

As already intimated the family foreshadows the VINCULARID/E.
Among Palaeozoic Bryozoa the BATOSTOMELLID^E offer the most

BRYOZOA. 365

points of resemblance. The relationship to Stenopora would
scarcely be even suggested by a comparison between the typical
species of that genus and of Rbombopora, yet, when the com-
parison is extended to a large number of species, it becomes
clear enough. For instance, Stenopora ramosa and Rhombo-
pora crassa Ulr., may be compared through Stenopora? signata.
A clear line of relation passes from— say, Rhombopora dicho-
toma. through R. incrassata, Anisotrrpa? elegantula Ulr., and
A. solida, to Stenopora ramosa. Again, if we pass from R.
siwulatrix, R. decipiens, R. tabulata and R. minor to R. ?
n*]>erula, but a short step is required to bring us to Batosto-
inella nitida and B. spinulosa.

Despite the close relationship suggested by the above lines of
comparative inquiry, I have placed the two families in different
suborders. My reason for doing so is that, notwithstanding
the numerous points of agreement, there always remains one
peculiarity to disting-uish them. This is the presence of hemi-
septa in the RHABDOMESOXTID.E, and their absence in the BATO-
STOMELLID.E. These structures are known only among the CRYP-
TOSTOMATA, of which they constitute one of the most important
and characteristic features. That the primitive portion of the
zooecia of this family is tubular, is, I believe, largely accounted
for by the fact that the distance from the center of the branches
to their surface is too great to admit of short cells. The much
shorter zooecia of the new genus Coeloconus, which compare
favorably with those of the STICTOPORID.E, lend plausibility to
this view. Still I would not for a moment deny the importance,
from a morphological point of view, of the relationship above
shown.

(10) STREBLOTRYPID.E: — In this family the zoarium may be
ramose, bifoliate, or unilaininar, the primitive portion of the
zocecia tubular in the first, and sub-tubular in the other modes
of growth. Hemisepta may be present or wanting. The aper-
ture which is usually circular, or elliptical is in other forms
decidedly truncated at the posterior margin. The front of the
cell back of the aperture, is simply depressed or exhibits from
two to twelve or more small pits. When the latter are numer-
ous they are generally arranged in two longitudinal series.

366 PALEONTOLOGY OF ILLINOIS.

This family will provisionally include Streblotrypa, Wortheno-
pora, Cydopora Prout, Proutella and Hyphasmopora R.
Ether, jr., the last mainly upon the authority of Mr. Vine, who
considers the genus related to Stivblotrypa.

As regards the systematic position of the genera, I should
say that Cydopora fungia Prout, is related to the Ptilodictyo-
nidae (compare fig. 2b and lie in text with fig. 3c, d, and e, on
PI. LXVIII); Streblotrypa compares on one side with Ehombo-
pora, and on the other agrees in important features with Intra-
pora basalis. In Worthenopora and Proutella, I believe we see
the nearest approach to the Escharidze yet known from Palaeo-
zoic rocks, but as careful search of many specimens has failed
to reveal accessory cells of any kind, it has appeared better to
arrange the genera with the STREBLOTRYPHLE than with that
family.

(11) HELIOTRYPID.E: — This provisional family is founded upon
the peculiar genus Heliotrypa. For its characters the reader is
referred to the original description and figures* and to the fol-
lowing synopsis of classification.

V. CHILOSTOMATA: — Paleschara Hall, is the only Palaeozoic
genus that my present views will admit of placing in this sub-
order. As near as I can determine, the affinities of the genus,
for which the new family PALESCHARiDJi; is proposed, are nearer
to the MEMBRANIPORID^E than to any other.

*Am. Pal. Bry., Jour. Gin. Soc. Nat. Hist, vol. 6, p. 277, 1883.

BRYOZOA. 367

SYNOPSIS OF CLASSIFICATION.

Order GYMXOL-EMATA Allinann.
Sub-order CTEXOSTOMATA Busk.

Family ASCODICTYOXUXE Ulrich.

Zoaria adnate, consisting of radially arranged filiform, fusi-
form, or bulbous zooecia; or of sub-fusiform uniserial cells.
Substance? corneo-calcareous.

< >DICTYON Nicholson and Ethridge, jr. — Zooecia consisting of
radially arranged, fusiform or bulbous zooecia, or filiform threads
with periodic swellings.

Type: A. fusiforwe Xich. and Ethr. jr. Range, Cincinnati
group to Coal Measures.

RHOPALOXARIA Ulrich. — Cells slender, fusiform, arranged in a
single anastomosing series. Cell mouths small, near one end of
the cells. The animal had the power of excavating the sub-
stance of the body upon which it grew.

Type: E. venosa Or. Range, Trenton and Cincinnati.

Suborder CYCLOSTOMATA Busk.

Family TUBULIPORID-E Busk.

STOMATOPOBA Bronn. — Zoaria adnate. with the zooecia in a
single branching series. Zooecia tubular, the apertures circular,
more or less elevated, subterminal. Walls finely porous.

Type: S. dicbotoma Larnx. Range, Trenton to Recent.

368 PALAEONTOLOGY OF ILLINOIS.

PROBOSCINA Audouin. — Like the preceeding, but with the cells
in two or more series, and the apertures slightly constricted.

Type: — ? — Range, Cincinnati to Recent.

BERENICEA Lamx. (SageneUa Hall). — Zoaria forming delicate
incrustations upon foreign bodies; sometimes consisting of sev-
eral superimposed layers. Zooecia as in the preceding.

Type: B. diluviana Lamx. Range, Trenton to Recent, but
not as yet known from Devonian and Carboniferous strata. The
same is true of Stomatopora and Proboscina.

Clonopora, Cystopora, Hederella, Ptilionella* and JHernodm,
are genera lately proposed by Prof. Hall. Judging from his
brief descriptions only, it seems probable that they refer to
Bryozoa having affinities with the TUBULIFORILLE. All are from
Devonian deposits.

Family FRONDIPORIDTE Reuss.

SCENELLOPORA Ulrich. — Zoaria broad-obconical, the under side
with an epitheca, the upper slightly concave and celluliferous.
Zooecia with subcircular apertures, occupying the summits of
radiating ridges. Intermediate spaces smooth, without cells.

Type: S. radiata Ulr. Range, Trenton.

Family PHACELOPORID^E n. fam.

Zoaria segmented; the zooecia conical, combined in bundles
of two or more to form conical segments.

PHACELOPORA n. gen. — Zoarium articulated; segments short,
conical, consisting of two or more equal, conical zooecia, with
slightly contracted circular apertures.

Type: P. pertenuis Ulr. Range, Trenton to Cincinnati.

Family ENTALOPHORIDJS Reuss.

DIPLOCLEMA n. gen. — Zoaria ramose, ovate in cross section.
Zooecia tubular, long, apparently moniliform proximally, separ-
ated internally by an axial lamina from which they gradually
diverge to open up on the two sides of the compressed branches.
Apertures prominent, isolated, somewhat constricted and cir-
cular. External wall thin.

"This genus is the same as Reptaria proposed Rolle in 1851. (See Pal. N. Y. Vol. 6.)

BRYOZOA. 369

Types: D. trentonense n. sp.,* from the Trenton group of
NV\\ York, and D? sparsum (Trematopora sparsa Hall) from
the Niagara group.

MITOCLEMA Ulrich. — Zoaria ramose, slender, subcircular in
transverse section. Zooecia tubular, very long, gradually diverg-
ing in all directions from an imaginary axis. Apertures prom-
inent, circular, arranged in transverse series around the stems.
AYalls thin.

Type: M. cinctosum Ulrich. Range, Chazy. (For internal
structure see PI. LIII).

PROTOCRISINA n. gen. — Zoaria ramose, celluliferous on one side
only. Zooecia subtubular, with prominently exerted circular aper-
tures. Reverse finely grano-striate. Small pores, apparently
communicating with the interior of the zooecia, are rather irre-
gularly distributed over both sides of the branches. Axis thin,
cruciform in transverse section. External walls thick.

Type: P. exigua n. sp. (PI. LIII, fig. 11-llc). Range, Tren-
ton and Cincinnati.

Sub-order TREPOSTOMATA Ulrich.

Family MONTICULIPORID.E Nicholson.
(Emended and restricted.)

Zoaria massive, discoid or lamellar, ramose or bifoliate.
Zooecia with thin and probably minutely perforated walls, the
peculiar granular structure exhibited in thin sections being
strongly indicative of an originally porous condition. Aper-
tures polygonal, rounded, or irregularly petaloid. Mesopores

* DipJocleina trentonense TTlr.— As this spec-ies has not yet been described, I append
here a brief diagnosis of its characters. Zoarium slender, ramose, dividing dichoto-
mously at an angle varying from 70 to 90 degrees; intervals between divisions, 5 mm., a
little more or less. Branches 0.55 mm. wide, 0.35 to 0.4 mm. thick. Zooecia tubular, in
tangential sections faintly moniliforni near their origin. Apertures slightly constricted,
p eminent, circular. 0.1 mm. in diameter, in three or four rows on each side of the
branch; generally arranged in oblique rows, less commonly transversely; at other times
irregular, four or five in 2 mm. measuring longitudinally; transversely the interspaces
are shorter.

The species is Quite common at Trenton Falls, N. Y. The internal structure of i
D. trentonense and D. sparsum is figured on PL LIII.

-46

370 PAL/EONTOLOGY OF ILLINOIS.

occasionally wanting, in other cases numerous; when present
they are angular and intersected by crowded horizontal dia-
phragms, often obscured by a secondary deposit. Acanthopores
abundant. Cystiphragms always present in the mature region.

MONTICULIPORA d'Orbigny. — Zoaria massive, lobate or lamel-
late, incrusting or free. Surface with monticules, or even.
Zooecia polygonal, thin-walled. Mesopores very few, generally
entirely absent. Acanthopores more or less numerous.

Type: M. mammulata d'Orb. Kange, Trenton to Hamilton.

ATACTOPORELLA Ulrich. — Zoaria generally forming thin crusts
over foreign bodies, rarely lobate, or subramose. Surface with
monticules. Zooecia with very thin inflected walls, the apertures
irregularly petaloid. Mesopores numerous, frequently isolating
the zooecia, and largely filled, especially near the surface, by a
secondary deposit. Acanthopores very abundant, generally en-
croaching upon the zocecial cavity.

Type: A. typicaJis Ulr. Kange, Trenton to Cincinnati.

HOMOTRYPELLA Ulrich. — Irregularly ramose. Monticules want-
ing, small maculae usually present. Zooecia with moderately
thick or thin walls. Apertures sub-circular, sometimes faintly
petaloid. Mesopores abundant, more or less completely isolat-
ing the zooecia. Cystiphragms generally developed only in the
median region of the zooecial tubes, being usually absent just
beneath the surface and never present in the axial region.
Acanthopores numerous.

Type: H. instabilis Ulr. Range, Trenton to Clinton.

PERONOPORA Nicholson. — Zoaria bifoliate, the surface even,
usually with small maculae. Mesopores and aeanthopores vary-
ing in number. Cystiphragms abundant, present throughout the
mature region in the zooecial tubes. Apertures circular or poly-
gonal. Zooecial walls comparatively thick, sometimes ring-like
in transverse section.

Type: P. decipiens Rominger, sp. — Cincinnati group.

HOMOTRYPA Ulrich. — Ramose to frondescent, with or without
monticules. Mesopores occasionally wanting, always few, some-
times gathered into clusters. Zooecial tubes with verv thin walls
and remote diaphragms in the large axial or immature region ;

BRYOZOA. 371

cystiphragms are developed just before opening at the surface.
Apertures subcircuiar or polygonal, the shape depending on the
thickness of the interspaces. Under favorable circumstances tan-
gential sections exhibit what appears to be large communica-
tion pores.
Type: H. curvata Ulrich. Range, Trenton to Niagara.

PRASOPORA Nicholson and Ethridge. — Zoaria forming hemi-
spheric, discoid, or, irregular masses, and, more rarely, thin ex-
pansions; usually free, with an epithecal covering on the lower
side. Zooecial tubes prismatic or cylindrical, thin-walled, largely
separated from each other by small angular mesopores, which
are generally quite inconspicuous at the surface. Acanthopores
usually present, but only occasionally either numerous or strong.
Cystiphragms in all the zooecial tubes. Diaphragms crowded in
the mesopores.

Type: H. grayte Nich. and Ethr. Range, Trenton to Cincin-
nati.

Family HETEROTRYPHLE n. fam.

Zoaria frondescent, ramose or parasitic. Zooecia polygonal,
walls comparatively thin and more or less contiguous; rarely
sub-oval, with thick walls. Line of separation between adjoin-
ing zooecia more or less clearly defined. Mesopores varying
from very few to numerous. Acanthopores present, sometimes
of large size. Diaphragms numerous, usually horizontal. Cysti-
phragms wanting.

HETEROTRYPA Nicholson. — Zoaria frondescent, sub-ramose, or,
rarely, incrusting. Zooecial tubes prismatic, sometimes sub-
cylindrical. Apertures angular, sub-circular, or slightly peta-
loid. Walls moderately thin. Mesopores varying in number,
sometimes abundant, with illy defined walls. Acanthopores
small, generally numerous. Diaphragms well developed, usually
horizontal; sometimes a few may be concave or recurved.

Type: H. frondosa d'Orb. sp. Cincinnati group.

DEKAYIA Edwards and Haime.— Ramose; branches cylindrical
or compressed. Zoo?cia polygonal, walls thin. Mesopores few.

872 PALEONTOLOGY OF ILLINOIS.

restricted to the monticules or maculae. Acanthopores originat-
ing in the axial region, sometimes very large, in other cases
more numerous and smaller. Apertures closed at intervals by
a thin calcareous pellicle.

Type: D. aspera Edwards and Hairne. Range, Trenton to
Hamilton.

PETIGOPORA Ulrich. — Zoaria parasitic, with a narrow non-po-
riferous band along the outer margin. Mesopores absent.
Acanthopores well developed, abundant.

Type: P. gregaria Ulr. Range, Trenton to Cincinnati.

DEKAYELLA Ulrich. — Ramose, branches sometimes compressed.
Mesopores more or less numerously distributed among the
zocecia, and often aggregated into irregular "maculae." Acan-
thopores of two sizes, the smaller ones the most abundant and
only present in the peripheral region. Those of the large size
commence in the axial region. Diaphragms horizontal.

Type: D. obscura Ulr. Cincinnati group.

Family CALLOPORIDJE, n. fam.

Zoaria ramose, sub-frondescent, or discoidal. Zooecia gener-
ally sub-circular, rarely polygonal, separated from each other
more or less completely by angular mesopores. Walls usually
thin, sometimes thickened and ring-like in transverse section.
Apertures closed by centrally perforated covers, which, as
growth proceeds, are left behind in the tubes to form the floors
of the succeeding chambers. Acanthopores wanting in the typi-
cal forms, very small when present.

CALL/OPORA Hall. — Ramose to sub-frondescent, or sub-pyriform,
smooth or tuberculated. Zooecia with thin walls varying,
according to the number of mesopores, from circular to poly-
gonal. Apertures in the perfect state closed by opercular covers;
perforation small, central, generally surrounded by radiating
ridges. Mesopores angular or rounded, more or less numerous,
sometimes completely isolating the zooecia, with crowded dia-
phragms. Zooecial tubes slowly attaining their full development,
closely tabulated near their origin in the axial region; the dia-

BRYOZOA. 373

phragms more distant farther along in the tubes. Transverse
sections show that' the tubes in the axial region are of two
sizes, the larger ones sub-circular, the smaller set angular. This
is one of the most characteristic features of the genus.

Type: C. eleg&ntula Hall. Range, Trenton to Lower Helder-
berg.

ASPIDOPORA Ulrich. — Very thin free expansions, with a con-
centrically and radially striated epitheca covering the lower side;
rarely parasitic. Typically composed of (according to age)
from one to many unequal spaces. Cells gradually increasing
in size from the margin of each convex space to near the center
of same. Mesopores numerous. Both kinds of tubes crossed
by diaphragms. Small acanthopores present.

Type: A. areolata Ulr. Cincinnati group.

CALLOPORELLA Ulrich. — Free or encrusting, thin expansions.
Surface smooth or undulated. Zocecial tubes cylindrical, with
thick walls, separated by one or two rows of angular meso-
pores. Zooecia apertures sub-circular, arranged in regular inter-
secting series. Diaphragms numerous, straight. Acanthopores
small and few.

Type: C. harrisi Ulrich. Cincinnati to Niagara.

Family TREMATOPORID.E n. fam.

Zoaria ramose, irregularly frondescent, or parasitic. Zooecial
tubes thin-walled and prismatic in the immature, sub-cylindri-
cal in the mature region. Apertures circular, oval, or petaloid,
with a more or less distinct peristome. Mesopores angular,
abundant, usually isolating the zooecia, closed at the surface ;
the closure with numerous perforations showing as small hollow
spines or granules. Acanthopores often wanting. Zooecial tubes
and mesopores with diaphragms.

TREMATOPORA Hall. Zoaria ramose; branches solid, even or
montiferous. Zooecia with oval or sub-circular apertures, sur-
rounded by a more or less elevated peristome. Interspaces de-
pressed, sometimes exhibiting the closed mouths of the abun-
dant mesopores. Zooecial tubes with thin walls and few dia-
phragms. Mesopores irregularly angular, generally exhibiting

374 PAL/EONTOLOGY OF ILLINOIS.

an obscurely beaded appearance in vertical sections, with a
diaphragm at the constriction. Acanthopores of moderate or
small size usually present.

Type: T. tuberculosa Hall. Range, Trenton to Niagara.

NICHOLSONELLA n. gen. — Zoaria consisting of irregularly inter-
twining flattened branches or fronds, sometimes laminated. Zo-
cecia tubular, with a few diaphragms in the "mature" region.
Apertures circular, with a faint granose peristome. Interspaces
wide, occupied by numerous angular mesopores, that more or
less completely isolate the zooecia. Walls of both the zooecia
and mesopores thin, and in the mature region traversed longi-
tudinally by minute tubuli. The interzocecial spaces are filled
with a calcareous deposit, into which the minute tubuli con-
tinue, but in which the mesopore walls become unrecognizable.
Mesopores with rather thick and numerous diaphragms.

Type: N. pondurosa n. sp. Range, Trenton and Cincinnati.

CONSTELLARIA Dana. — Subramose or frondescent zoaria. Sur-
face with stellate maculae, the spaces between the rays more or
less elevated and occupied by .two or three short rows or clus-
ters of closely approximated zocecial apertures. Zooecia with
rather thin walls, small, circular apertures and peristome,
equally distributed and partly in contact with each other in
the spaces between the stellate maculae. Mesopores abundant,
aggregated in the maculae, always closed at the surface, with
gradually crowding horizontal diaphragms. Zooecial tubes with
few or moderately numerous diaphragms. True acanthopores
wanting.

Type: C. florida, Ulr. Range, Trenton to Cincinnati.

STELLIPORA Hall. — Zoaria forming thin crusts over foreign
bodies. The upper surface exhibiting at rather irregular inter-
vals stellate monticules. Zooecia with sub-circular apertures
occupying only the summits of the radially arranged short
ridges, the depressed central space and furrows between the
ridges, as well as the intermacular spaces, appearing non-cellu-
liferous at the surface. Thin sections, however, show them to
have been occupied by rather small, angular mesopores, which
are more closely tabulated than the zooecial tubes, and like
them arise from the epithecal membrane.

BRYOZOA. 375

Type: S. antheloidea Hall, from the Trenton limestone.

IDIOTKYPA Ulrieh. — Zoaria parasitic. Zooecia sub-circular, with
a faint peristome, separated from each other by a series of
large irregular closed mesopores,. Zooecia and mesopores not
distinguishable in vertical sections, both being crossed by thick
parallel diaphragms, occurring at short and regular intervals.
Diaphragms apparently perforated by numerous minute fora-
mina. Walls with numerous minute vertical tubuli or cells.

Type: /. parasitica Ulrich. Trenton and Niagara.

Family BATOSTOMELLID.E n. fam.

Zoaria multiform, often consisting of superimposed layers;
never bifoliate. Zooecia with thick walls in the mature region,
where they usually appear fused together. Diaphragms hori-
zontal, those in the peripheral region centrally perforated,
originally functioning as covers to the cell apertures. Meso-
pores usually present, often intermittent, generally without dia-
phragms and distinct walls; when abundant they are small.
Acanthopores well developed.

BATOSTOMELLA Ulrich. — Ramose, branches slender, without
monticules. Zooecia thick-walled in the peripheral region, inter-
sected by remote, delicate, originally perforated diaphragms.
Apertures small, circular or oval. Interspaces rounded, thick,
spinulose: the acanthopores small and usually very numerous.
Mesopores subcircular, small, varying in number.

Types: B. spinulosa n. sp., and B. gracilis Nicholson. Tren-
ton to Coal Measures.

STENOPOKA Lonsdale. — Zoarium ramose, sublobate, massive,
laminar or parasitic. Surface even or montiferous. In the
mature region the zooecial tube walls are periodically thickened
so as to appear moniliform in vertical sections. Comparatively
large acanthopores are developed at the angles of the cells.
Diaphragms straight, more or less numerous, with a large cen-
tral perforation; a few irregular mesopores occasionally present.

Type: S. tfMiifinieiifiifi Lonsdale. Ranges through the Car-
boniferous svstem.

PALEONTOLOGY OF ILLINOIS. -

ANISOTRYPA Ulrich. — Zoaria ramose; branches irregular, hollow,
and lined on the inside with an epithecal membrane; or more
regular and solid. Zooecia with subcircular apertures. Inter-
spaces ridge-like, the comb sometimes with a series of extremely
minute granules. Acanthopores and mesopores wanting.

Type: A. symmetries Ulrich. Range, Keokuk to Chester.

BYTHOPORA Miller and Dyer. — Zoaria consisting of very slen-
der ramulets. Zooecial apertures oblique, lanceolate, narrowing
above. Interspaces varying in thickness, often channelled. Dia-
phragms practically wanting. Mesopores very few or absent.
Acanthopores comparatively strong, not numerous, rarely more
than one to each zooecium, sometimes wranting.

Type: B. fi'uticosa M. and D. Range, Trenton to Lower Hel-
derberg.

CALLOTRYPA Hall. — Zoaria ramose, slender, solid. Zooecia small,
oval, separated by one or two series of shallow often elongated
mesopores. An acanthopore sometimes present at the inferior
margin of the aperture.

Types: C. unispina Hall, and C. multiseriata Hall. Range,
Lower Helderberg to Hamilton. The genus will include, beside
the two species named, Hall's C. heteropora, and C. oculifera.

LEIOCLEMA Ulrich. — Zoaria ramose, lamellar, sub-globose, or
parasitic. Surface frequently exhibiting distinct monticules or
maculae. Zooecia with sub-circular or irregularly petaloid aper-
tures, separated by abundant angular mesopores, which appear
to be open at the surface in the typical species and closed in
others. Acanthopores numerous, situated in the walls of the
zocecia, strong in the typical forms, (giving the surface a spi-
nous character) and very small and inconspicuous in another
group of species. Diaphragms few in the zooecial tubes, fairly
abundant in the mesopores of the typical section, crowded in
the majority of the species now provisionally referred to the
genus.

Type: Callopora punctata Hall. Range, Cincinnati to Chester.

Family AMPLEXOPORIDJS n. fam.

Zoaria ramose, incrusting, discoidal, or massive, rarely bi-
foliate. Zooecia comparatively simple, prismatic, with a well

BRYOZOA. 377

marked divisional line between the walls of adjoining cells.
Mesopores practically absent, but small abortive cells some-
times occur among the large zooecia forming the monticules.
Acanthopores sometimes absent, generally abundant.

AMPLEXOPORA Ulrich.— Zoaria ramose. Zooecia polygonal,
forming prismatic tubes, which are thin-walled in the axial
region and more or less strongly thickened in the peripheral.
Mesopores wanting. Acanthopores always present, varying in
size and number. Diaphragms complete, horizontal.

Type: A. dngulata Ulrich. Range, Trenton to Hamilton.

MOXOTRYPELLA Ulrich.— In most respects like Amplexopora,
but differing in the absence of acanthopores. In one section of
the genus, the zooecia are often separated from each other in the
peripheral region by closely tabulated interspaces, that simu-
late mesopores.

Type: M. sequalis Ulrich. Range, Trenton to Hamilton.

PETALOTRYPA n. gen. — Zoaria bifoliate, consisting of irregular,
compressed branches or simple fronds, celluliferous on both
sides. Zooecial tubes prismatic, arising from a strongly flexu-
ous mesial line. Apertures subcircular or polygonal. Mesopore-
like interspaces that do not differ in their tabulation from the
zooecia may occur. Very small acanthopores (?) occupy many
of the angles of junction.

Type: P. compressa n. sp. Range, Lower Helderberg to Ham-
ilton.

ATACTOPORA Ulrich. — Zoaria thin, incrusting, often composed
of more than one layer. Zooecia with moderately thick walls,
the apertures indented or floriform, a peculiarity due to the
position of the very abundant acanthopores. These always
encroach upon the visceral cavity. Rather large solid maculae
or monticules, composed of numerous abortive cells, completely
filled by calcareous deposit, stud the surface at rythmical inter-
vals. Diaphragms thin, few, sometimes wanting.

Type: A. Im-suta Ulrich. Range, Trenton? and Cincinnati.

LEPTOTRYPA Ulrich. — Zoaria varying from thin incrustations
to free forms of discoidal, spiral, or elongate conical shape;
irregularly massive species occur also. Zooecia polygonal, with

—47

378 PALAEONTOLOGY OF ILLINOIS.

thin walls, and a variable number of delicate diaphragms.
Zooecia walls appreciably thickened in the mature region. Acan-
thopores small, more or less numerous, but nearly always re-
stricted to the angles of junction between the zooecia. Meso-
pores wanting.
Type: L. minima Ulrich. Range, Trenton to Hamilton.

(?) DISCOTRYPA Ulrich. — Zoaria consisting of very thin, free or
parasitic circular expansions. Surface with low broad monti-
cules, or even. Zooecia gradually decreasing in size from the
center of the monticules, very regular in their arrangement,
with thin walls, direct and generally hexagonal or rhomboidal
apertures. Mesopores and acanthopores entirely absent.

Type : D. slogans Ulrich. Range, Cincinnati to Upper Helder-
berg.

Family DIPLOTRYPID^E n. fam.

Zoaria hemispheric, massive or ramose. Zooecia forming com-
paratively large tubes of which the walls are more or less flexu-
ous and mostly very thin. Mesopores and acanthopores pres-
ent or wanting. Diaphragms very thin, developed at rather ir-
regular intervals. No cystiphragms.

DIPLOTRYPA Nicholson. — Zoarium generally free and of hemi-
spheric or discoid shape; in other cases massive, or forming thin
crusts. Zooecia with thin walls and rather irregularly distributed
horizontal or oblique diaphragms. Acanthopores wanting in
the typical species, but present in some of the others.

The genus as now understood, embraces at least three generi-
cally distinct sections, differing so much from each other as to
suggest affinities with as many different families.

The typical section comprises, so far as known, only two species,
the European type of the genus, D. petropolitana, Pander, sp.,
and D. westoni Ulrich, a species lately described from rocks in
Manitoba supposed to be of the age of the Cincinnati group.

Another section, typified by D. infida Ulr., from the Trenton
shales of Minnesota, is closely related to Praxopora, while the
Niagara species, D. milleri Ulr., is just as closely allied to Callopo-

BRYOZOA. 379

i-ella. It is difficult to place D. dubia Ulr., and one or two other
species, yet I am satisfied that they are not really congeneric with
D. petropolitana.

BATOSTOMA Ulrich. — Irregularly ramose, with a large basal
expansion. Zooecia with thin irregularly flexuous walls in the
axial region, more or less thickened in the peripheral. Typic-
ally the walls are irregularly ovate and ring-like, with those of
neighboring cells in contact only at limited points; the meso-
pores numerous, irregular in shape and size, and the acantho-
pores abundant and with a larger central cavity than usual.
Species vary from these to forms with polygonal, thin-walled
zoopcia and very few mesopores and acanthopores. Diaphragms
strong, horizontal, incomplete in several species.

Type: B. implicatum Nicholson. Range, Trenton to Cin-
cinnati.

MOXOTRYPA Nicholson, (Ptychonema Hall). — Zoaria irregular-
ly massive, discoid or subglobose, not divisible into mature and
immature regions. Zooecia comparatively large, prismatic, with
walls very thin throughout and often undulating or wrinkled
transversely; diaphragms remote. Both mesopores and acan-
thopores missing.

Type: M. undulata Nicholson. Range, Trenton to Lower
Helderberg, perhaps also in Devonian and Carboniferous de-
posits.

Family CERAMOPORIDJE Ulrich.

Zoaria usually incrusting, at other times discoid, lamellate,
massive, or forming more or less regular hollow branches;
rarely bifoliate. Zooecia with lunarium, the apertures usually
oblique, of subtri angular, ovate, or, more rarely, polygonal
form. The lunarium generally appearing at the surface as a
prominent over-arching hood. In forms with direct apertures
it appears as a slightlj- elevated portion of the margin, of cre-
scentic form, with the ends projecting more or less into the
apertures. Mesopores usually present, sometimes abundant,
always irregular and without diaphragms. In the zocecial tubes

880 PALEONTOLOGY OF ILLINOIS.

a few horizontal diaphragms are often present. Walls ap-
parently minutely porous, composed of irregularly laminated
tissue.

CERAMOPORA Hall. — Zoaria discoidal; free or attached by the
center of the base to foreign bodies. Under surface with one or
more layers of small, irregular, inter-communicating cells, which
do not form tubes. Zooecia large, oblique, imbricating, ar-
ranged in a radial manner around the depressed center, com-
municating with each other and the mesopores by means of
remote perforations in their walls. Mesopores irregular, short,
numerous at the center of the colony, decreasing in number
toward the margin.

Type: C. imbricata Hall. Niagara group.

CERAMOPORELLA Ulrich. — Zoaria incrusting, becoming massive
by super-imposition of numerous thin layers. Zooecial tubes
short, the Vails thin. Apertures more or less oblique, hooded,
commonly of oval shape. The hoods are directed away from
the centers of small maculae marking the surface at rythmical
intervals. Mesopores abundant, often completely isolating the
zooecia. In the fully matured state their apertures are closed
by a thin membrane. Diaphragms occasionally present in the
z official tubes.

Type: C. distinct^ Ulrich. Range, Trenton to Niagara.?

CREPIPORA Ulrich. — Usually incrusting, sometimes lamellate or
massive, with a wrinkled epitheca on the lower side; in one
case forming regular hollow branches. Surface exhibiting, at
subregular intervals, maculae of mesopores, appearing as min-
utely porous or subsolid elevations or depressions. Zooecia very
little oblique, the apertures varying from rhomboidal to sub-
pyriform. Lunarium well marked in perfect examples, but
easily overlooked when a little worn; best shown in tangential
sections. Mesopores usually restricted to the macula?. Dia-
phragms are developed in moderate numbers.
Type: C. simulans Ulrich. Range, Trenton to Upper Silurian.

DIAMESOPORA Hall. (Coeloclema Ulrich).— Zoaria ramose,
branches hollow, lined internally with a striated epitheca. Sur-
face with or without maculae. Zooecia with rather thick walls,
and sub-oval apertures. Peristome complete, but highest at

BRYOZOA. 381

the posterior side, making the aperture appear more oblique
than it actually is. Lunarium scarcely distinguishable in tan-
gential sections. Mesopores fairly numerous, rather equally dis-
tributed among the zooecia. Diaphragms usually absent; occa-
sionally one may be observed closing the apertures.

Type: D. dichotomy Hall. Range, Trenton to Lower Helder-
berg.

CHILOPOKELLA Ulrich. — Zoaria rising up into flabellate fronds
or compressed branches, from a greatly expanded heavy crust.
Zoopcial tubes long: very thin-walled, large, and of irregular
shape in the axial region. Walls much thickened near the sur-
face. Apertures ovate, the lunarium conspicuously elevated.
Mesopores numerous. Diaphragms few, generally absent.

Type: C. flabellata Ulrich. Cincinnati group.

AXOLOTICHIA n. gen. — Zoaria large, irregularly ramose or
digitate. Zooecia comparatively large, forming long sub-poly-
gonal tubes, intersected by remote diaphragms. Walls thin,
transversely lined in vertical sections. Apertures sub-oval, di-
rect, with the lunarium, which occupies about two-fifths of the
margin, elevated. Thin sections show the lunarium to have
been traversed vertically by from three to six minute, closely
tabulated tubes. Mesopores of irregular form, moderately
abundant, rather equally distributed among the zooecia.

Type: A. ponderosa Ulrich. Range, Trenton to Cincinnati.

SPATIOPORA Ulrich.— Zoaria forming thin parasitic crusts upon
foreign bodies, the shells of Orthoceras being the most favored.
Surface even or with monticules. Zoo?cia short with direct ir-
regular apertures. Lunarium scarcely perceptible even in thin
sections. Mesopores very few, usually absent. Interspaces often
with large blunt spines (?acanthopores). Walls of zooecia mod-
erately thin, with the characteristic structure pertaining to the
family.

Type: S. aspera Ulrich. Range, Cincinnati group; possibly to
the Niagara.

382 PALEONTOLOGY OF ILLINOIS.

Family FISTULIPORIDJS Ulrich.

Zoaria massive, laminar, bifoliate or ramose. Zocecia with a
more or less developed "lunarium," causing many modifications
in the form of the apertures; diaphragms horizontal. Inter-
spaces occupied by vesicular tissue. Cystiphragms and acantho-
pores wanting; eccentrically perforated opercular covers close
the perfect zooecial aperture.

FISTULIPORA McCoy, Lichenalia Hall, Thallostigma Hall,
Didymopora Ulrich.— Zoaria massive, lamellate, parasitic or
free, with a wrinkled epitheca below; less commonly sub-ramose,
the branches solid or hollow. Zocecia subradially arranged
about the surface maculae, with ovoid, sub-triangular, or pyri-
form apertures, the variations being due to the degree in which
the lunarium is developed; internally with thin walls and a
small number of complete horizontal diaphragms. Interspaces
smooth or granular, internally occupied by one or more series
of vesicular cells.

Type: Calamopora incrustans Phillips (Fistulipora minor Mc-
Coy). Range, Lower Silurian to Carboniferous.

A section of the genus that ought, perhaps, to be separated,
differs in having the zooecial apertures circular and the luna-
rium obsolete.

Type: F. communis Ulrich.

ERIDOPORA Ulrich, Pileotrypa Hall (pars). — Zoaria thin, para-
sitic. Zocecia with oblique, sub-triangular or ovoid apertures.
Lunarium very prominent.

Type: E. macrostoma Ulrich. Range, Niagara to Coal Meas-
ures.

CHILOTRYPA Ulrich (Coelocaulis Hall.) — Zoaria ramose, the
branches with a small, irregularly contracting and expanding
central tube. Zooecia with the posterior portion of the wall
thickest and strongty elevated hood-like, gradually thinning on
the sides, becoming linear at the front; the aperture elliptical
and oblique. Interstitial vesicles filled by a dense calcareous
deposit near the surface. Diaphragms few or absent.

Type: C. hispida Ulrich. Range, Niagara to Coal Measures.

BRYOZOA. 383

MEEKOPORA Ulrich.— Zoaria bifoliate, sometimes branching;
the median lamina? thin, flexuous. Zooecia not arranged : in
radial series around the solid maculae, but with their oblique
apertures directed towards the distal margin of the expansion.
Lunarium moderate or obsolete. Zocecial tubes oblique, the
anterior walls thinnest and flexuous. Diaphragms numerous,
often recurved. Ooeciuni a large oval cell, showing as a convex
space with a small apical perforation.

Type: M. eximia Ulrich. Range, Keokuk, St. Louis and Ches-
ter.

STROTOPORA Ulrich. — Zoarium ramose, branches large, irregu-
lar, solid or hollow. Large abruptly spreading cells, which are
supposed to represent ooecia, are distributed among the ordi-
nary zooecia. When well preserved they appear on the zoarial
surface as strongly convex nodes, about 0.5 mm. in diameter,
with an opening on one side.

In all other respects like Fistulipora^

Type: S. foveolata Ulrich. Range, Devonian to Lower Car-
boniferous.

LICHENOTRYPA Ulrich. — Zoaria thin, incrusting, with two dis-
tinct stages of development. In the first the colony resembles
an ordinary species of Fistvlipora, the zooecia having subcircu-
lar apertures, surrounded by a peristome that is thickest and
most elevated on the posterior side, the interspaces concave and
smooth. As growth proceeds, the peristomes of the adjacent
zooecia are united by thin irregular walls, which traverse the
interspaces and gradually form an elevated and very irregular
net -work, with still greater elevations at numerous points in
the shape of strong spines. Many of the zocecia keep pace with
the formation of this superficial structure, while others occup\r
the bottom of large cavities. Numerous subangular pores or
vesicles are interspersed among the zooecial apertures; the two
kinds of cells not easily distinguished.

Type and only specie's known: L. cavernosa Dlrich. Middle
Devonian.

BUSKOPORA Ulrich, (Odontotrypa Hall, Glossotrypa Hall,
Pileotrypa Hall (pars). — Zoaria thin, lamellate, incrusting or free.

384 PALEONTOLOGY OF ILLINOIS.

Zooecia with sub-circular apertures and a faint peristome; pos-
terior margin slightly more elevated than the anterior, with a
strong bidenticulate process (lunarium), extending nearly half
across the aperture, forming a ridge on the inner side of the
zooecia. The ridge is channelled along its inner termination.
A variable number of small accessory cells, with elevated sub-
circular apertures, is present, also a few large tumid cells
(ovicells?) occur among the ordinary zocecia.

Type: Fistulipora lunatu Rominger (B. dent at a Ulrich.)
Range, Devonian.

SELENOPORA Hall, Favicella Hall. Zoaria laminar or incrust-
ing. Inter-zooecial spaces occupied by two series of small vesicles,
separated by strongly elevated walls, forming the borders of
hexagonal concave spaces at whose centers the sub-circular
zooecia apertures are situated. The latter are surrounded by a
thin peristome, but the lunarium is obsolete.

Type: L. circincta Hall. Range, Upper Helderberg and Ham-
ilton.

? BOTRYLLOPORA Nicholson.— Zoaria simple or compound; when
simple, consisting of small circular parasitic disks, the upper
surface slightly convex, and marked by numerous radiating
ridges which terminate before reaching the depressed center.
Each ridge carries two rows of small contiguous rather thick-
walled zooecia. The depressed interspaces are smooth at the
surface, but internally are occupied by comparatively large
vesicles. When the zoarium is compound, it may consist of a
large number of such disks and, by superimposition of layers
of them, may eventually form small masses. The spaces be-
tween the disks a,re mainly occupied by very large vesicles,
possibly of the nature of ooecia. Diaphragms, several times
their diameter apart, cross the zooecial tubes.

Type. B. socialis Nicholson. Hamilton group.

PINACOTRYPA n. gen. — Zoarium consisting of thin contorted
expansions, with a wrinkled epitheca below. Zooecia with sub-
circular apertures, a well developed granose peristome, thin
walls and, so far as observed, no lunarium. Interspaces wide,
occupied by a single series of very large angular mesopores,

BRYOZOA. 385

which never present the appearance of vesicular tissue. Dia-
phragms horizontal, few in the zocecial tubes, numerous in the
mesopoi

Type: Fistulipora elegans Rominger (F. proporoides Nich.).
Range. Hamilton group.

Sub-order CKYPTOSTOMATA Vine.

Family CYSTODIOTYONID.E Ulrich.

Zoaria consisting of two or three layers of cells grown to-
gether back to back, forming thin foliate expansions or trian-
gular branches. Primitive cells semicordate or obovate-acumi-
nate in outline, arranged in longitudinal series between ver-
tical double plates. Primitive aperture subcircular, being some-
what truncated on the posterior side. As growth proceeds the
aperture is drawn out shaft-like, forming a tubular vestibule,
and the longitudinal plates become obsolete. Superficial aper-
ture with peristome and more or less developed lunarium. In-
terspaces between zooecia and vestibules occupied by vesicular
tissue, the vesicles more or less completely filled with a minutely
perforated calcareous deposit near the surface. Margin of
zoarium sharp or rounded, and like the basal portion, non-
cell uliferous.

CVSTODICTVA riridi. — Zoaria ramose, .bifoliate, the branches
acutely elliptical in cross section, with sub-parallel, sharp, non-
poriferous, striated, granulose, or smooth margins. Zoopcia
apertures generally arranged in longitudinal series between
ridges, sometimes in more pronounced oblique rows. Apertures
sub-elliptical, partially closed in the fully matured condition
with a more or less developed lunarium, that is always situated
upon the side nearest to the margin of a branch. Interspaces
finely striated, granulose, or smooth, and never with pits or
cells, excepting when worn.

Type: (.'. ocellntn Tlr.. and ('. piUwti Meek. Range, Upper
Helderberg to Coal Measures.

Cosrixir.M Keyserling, (Coscinotrypa Hall.— Zoaria composed
of flattened branches, celluliferous on both sides, which inosculate

—48

386 PALAEONTOLOGY OF ILLINOIS.

at short intervals till there is produced a broad frond per-
forated at rythmical intervals by circular or elliptical feuestrulcs.
In other respects like Cystodictya.

Type: C. cycJops, Keyserling. Range. Upper Helderberg to
Carboniferous.

DICHOTRYPA n. gen. — Zoaria consisting of large, thin, bifoliate
expansions. The surface with solid macuke. Zocecial structure
in conformity with that given for the family.

Type: D. foliata Ulr. Range, Niagara to St. Louis.

ACTINOTRYPA n. gen. — Zoaria very much as in Dlcliotryjm.
Zocecia apertures showing the projecting ends of from eight to
ten vertical septa-like ridges, that extend down on the inner
side of the tubular vestibule nearly or quite to the primitive
apertures.

Type and only known species A. peculiaris (Fistulipora pecu-
liaris Rom.), of the Keokuk group.

T.ENIOPORA Nich. — Zoaria consisting of dichotomously divided
branches as in Cystodictya, but differing from that genus in
having a strongly elevated longitudinal central ridge on each
face, causing the transverse section of the branch to be diamond
shaped. The ridges may be obtusely angular, or sharp, thin
and prominent. The zooecia apertures are arranged in a pin-
nate manner or in longitudial rows, and increase in size out-
ward.

Type: T. penniformis Nich. Hamilton group.

PRISMOPORA Hall. — Zoaria consisting of triangular branches
di-or trichotomously divided at irregular intervals; sides equal
or unequal, concave or flat, each celluliferous ; margins sharp,
straight or serrated, with a narrow solid border. In transverse
section the zooecia are seen to arise from internal laminap, which
radiate from the center to each angle, and divide the branches
into three subequal triangular portions. Apertures varying in
arrangment, frequently occupying the summits of small papillae.
Minute structures as given for the family.

Type; P. triquetra Hall. Range, Upper Helderberg to Coal
Measures.

BRYOZOA. 387

SCALARIPORA Hall. — Zoaria in every respect like those of Pris-
mopora, excepting that the faces of the triangular branches are
crossed by salient transverse ridges.

Type: S. scalariformis Hall. Range, Upper Helderberg to
Hamilton.

EVACTINOPORA Meek and Worthen. — Zoaria free, consisting of
four or more vertical leaves, which radiate from an imaginary
axis so as to present in transverse section a star-shaped or
cruciform outline. Rays thin, double, celluliferous on both faces,
and free in the upper half; united, thick and non-poriferous in
the basal portion; thickest and most dense at the outer and
under edges. Zooecia with subcircular apertures. Interspaces
apparently solid at the surface, occupied by vesicular tissue in-
ternally. As growth proceeded, a gradually increasing deposit
of minutely perforated calcareous laminae covered the lower and
older portions of the zoarium.

Type: E. radiata Meek and Worthen. Range, Burlington to
Keokuk group.

GLYPTOPORA Ulrich, (Ceramella Hall.) — Zoaria consisting of
thin bifoliate expansions, having both surfaces divided into
larger or smaller cup-shaped cavities, by the bifurcation and
coalescence of salient ridges; or of unilamellate bases, having
the coalescing ridges of the upper surface developed to such
a degree that they themselves form large expansions. The
ridges in both cases consist of two layers of cells growing in
opposite directions from a mesial lamina. The surfaces of
the ridges and the bottom of the cups exhibit rather regularly
distributed and more or less elongate solid maculae, which, as
thev are commonly depressed below the level of the surface,
have been called "dimples." Minute structure conforming with
that given for the family.

Type: G. plumosa and G. keyserlingi Prout. Range, Bur-
lington to Chester.

The following genera are placed here provisionally :

GONIOCLADIA Ethridge, Jr. Carboniferous of Great Britain.

CRISINELLA Hall. Lower Helderberg.

THAMNOTRYPA Hall. Lower Helderberg.

888 PALEONTOLOGY OF ILLINOIS.

ACROGENIA Hall. Hamilton. Founded upon a remarkable
species in which the zoarium is segmented very much as in
Dicranopora Ulr.

COSCINELLA Hall. Hamilton.

Family RHINOPORID.E n. fam. (Provisional.)

RHINOPORA Hall. — Zoaria bifoliate; forming large undulating
expansions, having the free lateral margins thickened and non-
poriferous. Surface without maculae or monticules, but when
perfect, exhibiting slender rounded bifurcating ridges, which,
when the zoariuin is a little worn, appear as shallow grooves.
The tubular structure thereby indicated is borne out by an ex-
amination of thin sections. These show further that they are
crossed by rather remote partitions. Zooecia apertures subcir-
cular, occupying the summits of prominent papillae, arranged
in more or less regular intersecting lines. Mesopores small,
about equal in number to the zocecia, sometimes showing at
the surface (?due to attrition). Large median tubuli between
the mesial laminae.

Type: JR, verrucosti Hall. Range, Clinton and Niagara.

Family STICTOPORID.E Ulrich. (Emended).

Zoaria bifoliate, consisting of compressed branches, or leaf-
like expansions. Primitive cells subquadrate, arranged in longi-
tudinal series. Both primitive and superficial aperture elliptical
or subcircular, sometimes a little truncated posteriorly when
the superior hemiseptum is more than usually developed. In-
ferior septum wanting. Median tubuli present between the
median laminae, and the longitudinal rows of zooecia vestibules.
Mesopores absent, but vesicular tissue sometimes present.

STICTOPORA Hall, (Rhinidictya Ulricn). — Zoaria composed of
narrow, compressed, dichotomously divided branches, with the
margins sharp, straight and essentially parallel; attached to
foreign bodies by a continuous expanded base. Zooecia aper-
tures sub-circular or elliptical, arranged alternately in longitu-

BRYOZOA. 389

dinal series between slightly elevated, straight or flexuous
ridges, carrying a^ crowded row of small blunt spines. Space
immediately surrounding apertures sloping up to summits of
ridges.

Type: S. fenestrata Hall. Range, Chazy to Cincinnati, and
perhaps also in Lower Helderberg.

EURYDICTYA n. gen. — Zoaria forming broad, simple or irregu-
larly divided, bifoliate expansions, without non-poriferous parallel
margins. Surface with more or less conspicuous, small, solid
maculae or monticules. Zocecial structure very much as in
Stictopora, the differences being of small importance and due to
zoarial habit.

Type: E. montifera Ulr. Range, Trenton to Cincinnati.

DICRANOPORA Ulrich. — Zoaria jointed; segments ligulate, rarely
simple, usually divided dichotomously at the upper end. Each
extremity somewhat thickened and solid. Minute structure and
arrangement of zocecia apertures as in Stictopora.

Type: D. internodia Miller & Dyer. Range, Trenton to Cin-
cinnati.

GONIOTRYPA Ulrich.— Like Dicranopora in all respects save
that there is a prominent median ridge on each of the two faces
of the double-leaved segments.

Type: G. bilateralis Ulrich. Cincinnati group.

EUSPILOPORA n. gen. — Zoaria consisting of small, flattened,
irregularly divided branches. Zooecia apertures subcircular or
elliptical, arranged in four or more rows over the central por-
tion of the branches between slightly elevated longitudinal
ridges, bearing numerous, small nodes. At brief intervals, occur-
ing alternately on each side of the branch, there are several
short rows of apertures directed obliquely upward and outward
from the central rows, extending nearly to the sharp margins.
Between these lateral rows the margin of the frond is more or
less indented, but a wide depressed non-poriferous space remains.
This is covered with exceedingly fine granulose striae. Thin sec-
tions show that between the ends of the zooecia there is a verti-
cal series of shallow lenticular vesicles, separated from each
other by a thick layer of tissue. All the remaining interspaces
are traversed vertically by exceedingly numerous minute tubuli.

390 PALAEONTOLOGY OF ILLINOIS.

Type: E. serrata Ulrich. Range, Hamilton group.

PACHYDICTYA Ulrich. — Zoaria varying from parallel margined
narrow branches to large undulating expansions. The edges
are acute and have a non-celluliferous border. In the larger
species the surface exhibits solid granulose maculae. Zooecia
rising rather abruptly from the mesial laminae, near which they
have very thin walls, are broad elliptical or subquadrate in out-
line, arranged in longitudinal series and partially separated
from each other by small vesicles. Toward the surface their
walls are thickened, ring-like, and usually completely isolated,
and the interspaces solid. Median tubuli well developed between
the mesial laminae, and in one or two rows between the zooecia.
Apertures plain or with slight peristome. Diaphragms cross
the zooecia tubes.

Type : P. robusta Ulr. Range, Trenton to Lower Helderberg.

PHYLLODICTYA Ulrich. — Zoaria leaf-like, or consisting of irregu-
lar broad branches. Zooecia tubular, the prostrate portion
long; apertures circular, slightly oblique, with the posterior
margin elevated. Interspaces wide, solid, granulose, traversed
vertically by numerous minute tubuli. A few diaphragms pres-
ent.

Type: P. frondosa, Ulr. Range, Trenton.

Family PTILODICTYONID.E Zittel.

Zoaria segmented or continuous, bifoliate. Zooecia sub-tubular,
the primitive cell more or less elongated, subquadrate, rhombic,
or hexagonal in outline, with thin walls. Both superior and
inferior hemisepta generally present. Vestibular portion with
thick and often ring-like walls, the central region between the
cavities usually of conspicuously lighter or darker color than
the rest. When wide the region usually appears transversely
lined; at other times occupied by untabulated mesopores.
Median tubuli wanting.

PTILODICTYA Lonsdale. (Escharopora Hall, Heterodict.va
Nich.) — Zoaria segmented, consisting of a small, radially striated
basal expansion which is attached to foreign bodies, and has
at the center of the upper surface a socket for articulation with
1lie sub-solid extremity of the erect and unjointed frond. Frond

BRYOZOA.

391

commonly lanceolate or falciform, sometimes a broad undulat-
ing expansion, at other times dichotomously branched with the
margins parallel. Proximal extremity longitudinally striated,
pointed or wedge-shaped. Lateral margins of frond acute, non-
celluliferous, smooth or obliquely striated. Small monticules
usually present in the large species. Zocecia with subcircular or
elliptical superficial apertures, surrounded by a sloping area of
quadrate, rhombic or hexagonal outline. Apertures arranged
in a plumose manner, with longitudinal series in the center and,
diverging from these on each side, oblique lateral rows; or
simply in regular diagonally intersecting series. Both hemisepta
usually well developed.

Type: P. lanceolata Goldf. Range, Trenton to Upper Helder-
berg.

F:^. 11. Sections of Ptilodictya. All the figures are magnified x25.— a. Portion of a
vertical section of Ptilodictya magnified S. A. Miller, showing several zooecia with hemi-
septa ;— b, b', and b". three portions of a tangential section of same, showing structure of
zoarium at various depths below rhe surface :—c, zooecium of same sectioned just be-
neath the aperture, and showing slightly different structure from what is seen in 6."—
d, vertical section of Ptilodictya lanceolata Goldf.. from Gotland;— e. tangential section
of the American representative of the species; Clinton gr., Dayton, Ohio. (P. erjtanfn
Hall, Ind. Geol. Sur., voL 12, 1882, not Phaenopora expansa Hall and Whitfleld. Pal. Ohio,
voL n, 1875).

392

PALEONTOLOGY OF ILLINOIS.

CLATHROPORA Hall. — Zoaria composed of anastomosing
branches, forming a regular net-work with round f,:iestrules.
Minute structure essentially the same as in Ptilodictya,.

Type: C. frondosa Hall. Range (?) Trenton to Upper Hel-
derberg.

PILENOPORA Hall.— Zoaria as in Ptilodictya, from which they
differ in having two mesopores between the ends of the zooecia
apertures.

Type: P. explamitn Hall. Range, Cincinnati to Lower Hel-
derberg.

0- V

Fig. 12. Sections illustrating the internal structure of Phcenopora; allx25.— a, tangen-
tial section of P. constellata Hall, showing structure of zoarium just beneath the sur-
face;— l>, half of a vertical section of same;— c, deep tangential section of P. expansa H. &
W., showing structure of zoarium just above the median laminae;— d, tangential section
of P. lindstromi n. sp., showing the pitted margin and three rows of zocecia;— e, vertical
section of same.*

* Phasnopora lindstromi is from the Upper Silurian deposits of Gotland. It grows
into narrow, parallel-margined, compressed branches, about 1.5 mm., thick, 3.8 to 4.5
mm. wide, bifurcating at intervals of 10 mm. more or less. Margins wide, rather
sharp, with several rows of small pits. Zocecia apertures elliptical, about 0.19 mm. long,
arranged in 9 to 12 longitudinal series, 14 in 5 mm. Between the ends of the apertures
are the usual two mesopores.

I am indebted to the eminent palaeontologist, Dr. Gustav Lindstrom, of Stockholm,
Sweden, for an excellent example.

BRYOZOA. :>,'.>:',

<ii;Ai'T<uu<TYA I'lrich. — Zoaria rising from a pointed articulat-
ing base into continuous dichotomously divided narrow fronds.
Zo'i'cia with sulK-ircular aperture, surrounded by a low pc-ris-
tome subpolygonal in outline. Inters] >ac»>s depressed, generally
linear, sometimes with one or two fine tortuous elevated lines;
vertically lined in longitudinal sections, but with the lines in-
terrupted. Median lamina? straight in transverse sections.

Type: G. pei-elegnns Ulrich. Range, Trenton to Cincinnati.

ARTHROPORA Ulrich.— Zoaria bushy, spread in a plane, coin-
posed of numerous segments; joints sometimes simple, usually
with several short lateral branchlets. some of which may be
tipped for articulation with succeeding segments. Zocecia with
elliptical or subpyriform apertures and elevated margins. In-
terspaces with one or more vermicular stria?. Apertures, when
perfect, closed by centrally perforated opercular structures.
Median lamina? zig-zag in transverse sections.

Type: Stictoporti shnfferi Meek. Range, Trenton and Cincin-
nati.

T.EMODHTYA ii. gnu. — Zoaria growing from a basal expansion
into dichotomously divided narrow branches or broad fronds.
Zooecial structure very much as in some species of Ptilodictyn
(P. pavomn D'Orb.). Apertures elliptical or subcircular, sur-
rounded by a sloping area. Interspaces ridge-like. Both ''hemi-
sppta" present.

Type: T. ramulosx n. sp. Range, upper Helderberg to St.
Louis.

PIILOTRYPA n. gen. — Zoaria forming large ramose expansions.
Zooecial tubes and apertures very oblique. At the upper ex-
tremity of the acutely ovate aperture there is a small cell which
is best seen in tangential sections. Surface with irregular, longi-
tudinally channelled spots.

Type and only known species: P. obliquatu n. sp. Cincinnati
group.

STICTOTRYPA n. gnu. — Zoaria consisting of dichotomously di-
vided, narrow, compressed branches. Zooecial apertures circular
or elliptical, surrounded by a distinct, evenly elevated peristome.
Interspaces flat or concave, composed of horizontally laminated
solid tissue.

Tvpe: Stictopora similis Hall. Range, Trenton to Niagara.
-49

394

PALEONTOLOGY OF ILLINOIS.

Fig. U. a. tangential section of Sticto-
porella interstincta Ul. (Gin. gr.); b, ver-
tical section of same.

Fig. 13.— a, vertical section of Stictotrypa punctipora Hall (sp.).— b, vertical section
of Stictotrypa similis Hall (sp.).— c, tangential section of same. All x25.

STICTOPORELLA Ulrich.— Zoaria
branching, cribrose, or leaflike.
Zooecia with the primitive por-
tion tubular and unusually long.
Superior hemisepta wanting; the
inferior ones sometimes present.
Apertures placed at the bottom
of a wide sloping area. More
or less numerous thick-walled
and untabulated mesopores oc-
cur between the zooecia apertures
and line the zoarial margin. In
the frondose species they also form clusters. Tangential sec-
tions show that both the zooecia and mesopores are separated
from each other by a sharply defined line.
Type: 8. interstincta Ulrich. Range, Trenton to (?) Chester.

INTRAPORA Hall, (Cosinella, Hall.) — Zoaria cribrose, branch-
ing, or sub-frondose. Zooecia with moderately thin walls, which
are not sharply distinguished from those of the numerous tabu-
lated mesopores which occupy the interspaces. Apertures sub-
circular, without area but enclosed by faintly elevated peri-
stomes. A short distance below the plane of the zooecia aper-
tures perfect specimens show a perforated diaphragm. Meso-
pores usually open at the surface, but sometimes completely
closed by a deposit of horizontally laminated calcareous
matter.

Type: /. puteolfita, Hall. Range, Devonian.

BRYOZOA. 395

Family FENESTELLID.E King.

Zoaria forming reticulate expansions, celluliferous on one side
only, composed of rigid branches united to each other by
regular non-poriferous bars called dissepiments; or they may
l»tj sinuous and anastomose; or even remain free. Primitive por-
tion of zoupcia of oblong quadrate or hexagonal outline. Su-
perior hemiseptum usually present, the inferior one less fre-
quently. Primitive aperture semi-elliptical, being truncated at
the posterior side. Superficial apertures rounded, with peris-
tome, and. in the perfect state, closed by centrally perforated
opercula.

FE.VESTELLA Lonsdale. — Zoaria flabellate to infundibuliform,
poriferous on the inside (always?); branches nearly straight,
and connected with each other at rhythmical intervals by non-
poriferous dissepiments. Zooecia in two rows, separated by a
more or less developed median keel.

Accepted type: F. plebeia, McCoy. Range, Cincinnati to Per-
mian.

SEMICOSCIXIUM Prout, (Carinopora Nicholson) — Zoaria funnel-
shaped, poriferous on the outer side. Dissepiments wide, very
short, the branches appearing on the non-poriferous side to
anastomose. Here, also, the fenestrules are sub-rhomboidal or
rounded. Zo<ecia in two ranges. Median keel very high and
more or less expanded at the summit.

Type: S. rhomboideum Prout. Range, Niagara to Hamilton.

FENESTRAPORA Hall. — In all respects like Semicoscinium, ex-
cepting that the reverse of the zoariurn and the expanded sum-
mits of the carinse bear large pores or pits.

Type: F. biperforata Hall. Range, Upper Helderberg and
Hamilton.

ISOTRYPA Hall (emended). — Zoaria infundibuliform; branches
connected by dissepiments. Keel at first very thin, then
abruptly expanded; at intervals corresponding to the true dis-
sepiments, the thickened summits are connected by strong pro-

3g 8, giving to the superstructure an appearance very much
like that of the reverse faee of the frond. Zocecia in two ranges.

Type: /. conjunctiva Hall. Range, Niagara to Hamilton.

396 PALAEONTOLOGY OF ILLINOIS.

I'NITRYPA Hall. — Zoaria infundibuliform; zocpcia in two ranges.
Keels as in Semicoscinium, but with their summits connected
by sub-imbricating transverse bars or plates, which may be as
numerous as the zooecia, or only two to each fenestrule.

Type: U. lata, Hall. Range, Lower Helderberg to Hamilton.

HEMITRYPA 1'hillips. — Zoaria funnel-shaped or undulating-
foliar expansions; branches rigid. Zocecia in two ranges, their
apertures separated by a moderately developed keel. The latter
is elevated at regular intervals into small pillars, which, when
the superstructure they support is worn away, appear as spine-
like prominences. The superstructure consists of straight or
zigzag longitudinal bars, of which one is placed over each
branch upon the row of pillars, and another usually somewhat
thinner, suspended midway between the branches. These bars
are then connected by transverse processes, so as to leave regu-
lar, small, generally hexagonal openings, corresponding in num-
ber and position Avith the zooecial apertures beneath them.

Type: H. oculata Phillips. Range, Clinton to St. Louis.

HELICOPORA Claypole. — Zoaria spiral, the inner edge thickened
and non-poriferous, without, however, forming a solid central
axis. Other characters as in Fenestella.

Type: H. latispiralis Claypole. Range, Niagara and Devonian.

ARCHIMEDES Lesueur. Zoaria like those of Helicopora, but
differing in having a solid central axis.
Type: A. wortheni Hall. Range, Keokuk to Chester.

LYROPORA Hall. — Zoaria flabellate, the fenestrated portion
spread between two strong, non-celluliferous. diverging supports.
Zooecia in from two to five rows. Median keel obsolete.

Type: L. quincuncialis Hall. Range, Burlington to Chester.

FENESTRALIA Prout. — Zoaria strong, with two rows of cells on
each side of the median keel. In other respects like Polypom.

Type and only known species: F. sancti-ludovici Prout. St.
Louis group.

POLYPORA McCoy. — Zoaria in most respects like Fenestellfi,
but differing in having from two to six or even eight rows of
cells, and in wanting the characteristic median keel. The latter

BRYOZnA. 397

is sometimes represented by a row of strong tubercules. Such
species approacli Fenextralia Prout.

Original type: P. dendroides McCoy; accepted type: P. schn-
murdi Prout. Range. Niagara to Coal Measures.

THAMNisrrs King.— Zoaria differing from those of Polrpora,
in wanting the dissepiments entirely, or in having them recur
at very irregular and much longer intervals; besides, the branches
bifurcate more freely.

Type: T. dubius Schlotheim sp. Range Niagara to Permian.

PHYLLOPORA King. — Zoaria infundibuliform, consisting of an-
astomosing branches, which form a regular, round-meshed net-
work. Zooecia in two or more rows.

Type: P. ehrenbergi King. Range. Devonian to Permian.

(?) CRYPTOPORA Nicholson. May be the same as Henritrypn.
PTILOPORINA Hall.
PTILOPORELLA Hall.
(?) LOCULIPORA Hall.

Family ACAXTHOCLADIHXE Zittel (Ulrich emend).

Zoaria poriferous on one side only, dendroid, pinnate, or
forming feuestrated expansions; consisting of strong central
stems and numerous lateral branches which proceed from their
opposite margins. The lateral branches are free, or may unite
(in the feuestrated genera) with those of the adjacent branches.
Non-poriferous dissepiments absent. Zoupcia and minute charac-
ters as in the FEXESTELLID.K.

PIXXATOPORA Vine. (Glauconome of authors) —Zoaria small
and delicate. Lateral branches short, free. Cells in two rows,
one on each side of a moderately developed median keel, which
is fainter or wanting on the lateral branches.

Type: Glauconome elegans Y. & Y. Range, Lower Helder-
berg to Upper Coal Measures.

SEPTOPORA Prout. — Zoaria feuestrated, flabellate or leaf-like.
Primary branches numerous, increasing by bifurcation or inter-
polation, and so arranged that the smaller lateral branches
which proceed from their opposite margins unite with those of
the adjacent brandies. Reverse, or non-celluliferous side usually

898 PALAEONTOLOGY OF ILLINOIS.

with fine striae, and a variable number of scattered dimorphic
pores. Celluliferous side, with two rows of zocecia arranged as
in Pinnatopora. Apertures large.

Type: S, cestriensis Prout. Range, Chester, Lower and Upper
Coal Measures.

ACANTHOCLADIA King. — Zoaria like those of Pinnatopora, but
larger and with three or more rows of cells. Between these the
surface is elevated into small longitudinal ridges or series of
tubercles.

Type: A. anceps Schlotheim. Range, Upper Coal Measures to
Permian.

SYNOCLADIA King. — This genus differs from Acanthocladia in
the same manner as Septopora does from Pinnatopora, in
having the lateral branches of adjacent stems unite with each
other, thereby forming of the whole a fenestrated frond.

Type: S. virgulacea King. Permian.

DIPLOPORA Young & Young. Zoaria consisting of very slender-
straight stems, which throw off a few lateral branches of equal
dimensions; Cells in two rows. Median keel moderately de-
veloped.

Type: D. marginalia Y. & Y. Range, Chester and Coal Meas-
ures.

PTILOPORA McCoy. — Zoaria pinnate, the median branch
stronger, particularly on the reverse, than the oblique lateral
branches. The latter are united to each other at frequent in-
tervals by non-poriferous dissepiments. Zocecia in two ranges.

(?) Type: Retepora flustriformis Phillips (P. prouti Hall, is a
typical form.) Range, Hamilton to St. Louis.

Icthyorachis McCoy, Penniretepora D'Orb., and Ramipora
Toula probably belong here.

Family SPHRAGIOPORID.E n. fam.
Zoaria parasitic; zooecia of the same type as in the FENE-

STELLID,E.

SPHRAGIOPORA n. gen. — Zoaria parasitic, forming very small,
sub-hemispheric patches on foreign bodies. Zooecia with circular

BRYOZOA. 399

apertures and slight peristome, arranged in a sub-radial manner,
in single or double rows.

Type: S. parasitica n. sp. Range. Chester to Upper Coal
Bfeasun

Family PHYLLOPORINID.E n. fam.

Zoaria retiform and consisting of anastomosing branches; at
other times dichotomously branched; celluliferous on one side,
the other finely striated. Zocecia tubular, rather long, often
with diaphragms. Without hemisepta.

PHYLLOPORIXA n. gen. — Zoaria consisting of somewhat irregu-
larly anastomosing branches, with from two to eight ranges of
zocecia on the celluliferous side. Reverse convex, longitudinally
striated. Zocecia tubular, with or without diaphragms. Meso-
pores generally present, sometimes numerous, always closed at
the surface; with diaphragms.

Types: Retepora trentonensis Nich., and E. asperato-stiiata
Hall. Range, Chazy to Niagara.

CHAINODICTYON Fcerste. — Much like the preceding but the
zocecia somewhat shorter. Mesopores and diaphragms wanting.
Reverse flattened, concentrically undulated or striated.

Type: C. laxum Fcerste. Coal Measures.

DRYMOTKYPA n. gen. — Zoaria branching dic-hotomously at fre-
quent intervals. Reverse longitudinally striated. Zooecia in
several ranges, tubular,, thick-walled in tangential sections,
sj (ringing from a thin double plate, beneath which a number of
vesicles (? aborted zocecia) are present. Superficial apertures
angular, becoming oval a short distance within on account of
the thickening of the walls.

Type: Retepora diffusa Hall, (Pal. N. Y. vol. II, p. 160).
Niagara group.

The genus will also include Thamniscus cisseis Hall, (Lower
Held.) and T. niagarensis Hall. A fourth species from the Trenton
of Canada not yet described, I propose to name Drymotrypa
dichotoma*

*Drymotrypa dichotoma n. sp. PI. LIII, flg. 6.— Zoarium spreading in a plane, con-
sisting of frequently branching lax ramulets, one side of which is finely striated, the
other bearing the mouths of four ranges of zooecia; intervals between bifurcations

400 PALEONTOLOGY OF ILLINOIS.

Family ARTHROSTYLID.E Ulrich.

Zoaria articulated, ramose, consisting of numerous sub-cylindri-
cal segments, or, if dichotomously divided, of continuous branches,
which articulate with a slightly expanded attached base. Zo-
cecia sub-tubular, more or less oblique, radially arranged around
a central axis, opening on all sides of the segments; more
rarely, one side is non-celluliferous and striated longitudinally.

ARTHROSTYLUS. n. gen.* — Zoaria dichotomously divided, com-
posed of numerous slender equal segments, joined to each other
by terminal articulation ; poriferous on one side only ; opposite
side longitudinally striated. Zooecia arranged in three or more
rows, between carinse.

Type: Arthronema tenue Ulrich ("Amer. Pal. Bry.") Range,
Trenton and Cincinnati.

ARTHROCLEMA Billings. — Zoarium articulated, composed of
numerous sub-cylindrial segments arranged in a pinnate man-
ner, those forming the central stem the largest. Each of the
primary segments with one or two sockets on each side for
articulation with the smaller secondary segments; these again
in like manner articulate with still more slender tertiary seg-
ments. Celluliferous on all sides. Zooecia somewhat oblique,
with nearly direct oval apertures, arranged between elevated car-
inae. A diaphragm may intersect the tube at about the middle
of its length.

Type: A. pulchellum Billings. Range, Trenton and Cincinnati.

SCEPTROPORA 11. gen. — Segments club-shaped, the lower half
striated, non-celluliferous, the extremity bulbous ; upper half ex-
panded, the center of the top with a large socket. Zooecia tub-
ular, arranged between vertical lines; apertures sub-ovate.

about 1.5 mm. ; width of branches about 0.5 mm. Zooecial tubes arranged bilaterally
two on each side of a vertical lamina, not observed at the surface. Celluliferous face
not seen. Zooecia (as shown by tangential sections) tubular, with broadly oval aper-
tures, their longer diameter 0.12 mm., about four in one mm. Walls thin within, rapidly
thickening toward the aperture. One or two diaphragms in most of the tubes.

This interesting species I obtained from the Peter Bedpath Museum of Montreal,
Canada, through the kindness of Sir Wm. Dawson. The specimens were collected by
Mr. T. Curry, at Montreal, from the Trenton limestone.

* This name is proposed instead of Arthronema which was pre-occupied by sch-
scholtz.

BRYOZOA.

401

Type : #. fucula n. sp. Cincinnati group. Manitoba, and Wil-

mington. 111.

Fig. 15. Sceptropora facula n. sp. Cincinnati group, Stony Mountain, Manitoba.*— a.
A segment of the average size and appearance. — b. A vertical section, showing tubular
zooecia and central axis . — c. Transverse section of lower half of a segment, —d. Transvers e
section of expanded portion of a very large segment. All magnified to 18 diameters.

The segments vary in length from less than one mm. to nearly two mm.; the width
of the expanded top from 0.7 mm. to 2.0 mm. I am indebted to Prof. J. F. Whiteaves,
the palaeontologist to the Geological and Natural History Survey of Canada for the
opportunity of describing this unique species.

HELOPORA Hall. — Zoaria composed of subequal cylindrical
segments, articulating terminally, poriferous all around. Zooecial
tubes somewhat oblique, straight or geniculated. Apertures
sub-oval, arranged between slightly elevated lines, or in dia-
gonally intersecting series. Inferior border often prominent,
sometimes also bearing an acanthopore.

Type: H. fragilis Hall. Range, Trenton to Niagara.

XEMATOPORA n. gen. — Zoaria very slender, ramose, continuous
above the pointed basal extremity. Zooecia sub-tubular, short,
arranged in a radial manner around one or two minute axial
tubes. Apertures ovate or sub-circular, with peristome, gen-
erally arranged between longitudinal ridges. One or two dia-
phragms occasionally present.

Type: N. quadrats, n. sp. Trenton group. Range, Trenton
to Niagara.

Family RHABDOMESONTID.E Vine.

Zoaria ramose, solid, or with an axial tube. Zooecia with the
primitive portion tubular; hemisepta usually developed. Aper-

* I have lately collected this species at Wilmington, 111., a locality that has proven
exceedingly rich in Bryozoa. Also at Savannah, I1L

—50

402 PALEONTOLOGY OF ILLINOIS.

tures regularly arranged, oval or circular, placed at the bot-
tom of a sloping area, rhombic or hexagonal in outline, or
between straight or fiexuous longitudinal ridges. Acanthopores
and smaller spines generally present, but mesopores are absent.

RHOMBOPORA Meek, (Orthopora Hall.) — Zoaria slender, ramose,
solid. Zooecia with the vestibular or outer portion thick-
walled. Apertures arranged regularly in diagonally intersecting
or longitudinal lines. Strong acanthopores often present at the
angles of junction and more numerous, smaller spines, generally
occupy the summit of the ridge-like interspaces between the sub-
elliptical apertures. Diaphragms sometimes present in the axial
region.

Type: R. lepidodendroides Meek. Range, Niagara to Upper
Coal Measures.

RHABDOMESON Young and Young. — This genus differs from
Rhombopora only in having a slender axial tube, to which the
proximal ends of the zocecia are attached.

Type : Millepora gracilis Phillips. Carboniferous. This genus
is not known from American deposits.

CCELOCONUS n. gen. — Zoaria simple, hollow, expanding grad-
ually from the striated and sub-acute basal extremity; sub-
stance thin. External characters of zocecia as in Rhombopora;
primitive portion short. Hemisepta well developed.

Type: C. rhombicus n. sp. Range, St. Louis to Chester.

NEMATAXIS Hall. Upper Helderberg and Hamilton.

AOANTHOCLEMA Hall (pars.) Upper Helderberg to Warsaw.

BACTROPORA Hall. — Zoaria simple, unbranched, the lower ex-
tremity pointed. In other respects like Rhombopora.

Type: B. granistriata Hall. Upper Helderberg to Keokuk.

(?) TROPIDOPORA Hall. Upper Helderberg.

Family STREBLOTRYPIDJE Ulrich.

Zoaria variable. Zorecia with the primitive portion sub-tub-
ular or tubular; apertures sub-circular, often truncated pos-
teriorly, surrounded by a slightly elevated rim. Front, or
outer surface of cell back of the aperture, simply depressed, or
with from two to twelve or more small pits. Diaphragms
wanting.

BRYOZOA. 403

STREBLOTRYPA Ulrich. — Zoaria ramose, slender, solid. Zooecia
radiating from an imaginary axis, their primitive portion long,
tubular ; or from a linear axis when they are somewhat shorter.
Inferior hemisepta best developed, situated rather far down.
Apertures regularly elliptical, or somewhat truncated at the
posterior margin, surrounded by a slight peristome and, within
this, sometimes a narrow sloping area; arranged usually in
rather regular longitudinal series. Just back of the aperture,
occupying the depressed front of the cell, there are from one to
twelve or more small pits, which, when numerous, are arranged
in two or three rows. Very small acanthopores occasionally
present.

Type: S. nicklesi n. sp. Range, Hamilton to Chester.

WORTHENOPORA n. gen. — Zoaria bifoliate, branching or pal-
mate. Zoopcia very regularly arranged, sub-tubular, or rather,
elongate rhomboidal, with the aperture semi-elliptical. On the
surface the line of junction between the cells is marked by an
elevated ridge. The truncated posterior margin of the aperture
is raised into a less strong transverse bar. The elongate trian-
gular depressed front appears perfectly plain.

Type: W. spinosa n. sp. Range, Keokuk to St. Louis.

CYCLOPORA Prout. — Zoaria unilaininar, parasitic or free. Pri-
mitive portion of zooecia. sub-tubular. Apertures sub-circular or
somewhat truncated posteriorly, surrounded by a moderate,
granose or smooth, peristome; arrangement various. When
regularly developed there is a large oblong more or less shallow
depression between each four adjacent zooecia. With a less regu-
lar development, this space may be divided into two smaller
ones; or it may appear that the apertures are separated by
unequal and irregularly situated depressions. With growth
these interspaces are drawn out into tabulated mesopores.
(PI. LXYIII, fig. 3f.) Hemisepta very little developed.

Type: C. fungia Prout. Range, Keokuk and Warsaw beds.

PROUTELLA n. gen. — Zoarium discoid, thin, free, the lower sur-
face convex and lined with a concentrically wrinkled epitheca.
Primary zocpcia sub-tubular, the succeeding ones shorter, all
rather thin-walled. Aperture broad-elliptical, surrounded by a
very narrow sloping area, hexagonal in outline; when perfect,

404 PALEONTOLOGY OF ILLINOIS.

with a depressed delicate calcareous plate, that closes a little
less than two-thirds of the opening, the orifice left being sub-
triangular in form, without thickened margins, and situated at
the anterior side. With age, a second, third and more layers
of zooecia are developed directly over the first, so that they
gradually form a zocscial tube seemingly having the cavity in-
tersected by incomplete diaphragms. These appear to spring
from the posterior wall and extend about one-half the distance
across.

Type and only known species: Cyclopora discoideti Prout.
Keokuk group.

? CYCLOPOKELLA n. gen. — Zoarium a thin discoidal expansion.
Zooecia sub-tubular, with a succession of superior hemisepta in
the vestibular portion. Irregular mesopores abundant. Acan-
thopores of large size, numerous.

Type: C. spiinfera Ulrich. Keokuk group.

Family HELIOTKYPID.E Ulrich (Provisional.)

HELIOTRYPA IJlrich. — Zoarium bifoliate. Primitive portion of
zooecia sub-tubular, thin-walled and prostrate upon the median
laminae. Superior hemiseptum moderately developed. Vestibu-
lar or outer portion of the zooecia thick-walled, the walls tra-
versed obliquely by radially arranged minute tubuli. Inter-
spaces of variable width, occupied by numerous, irregular,
rounded, thick-walled and tabulated mesopores, which are also
aggregated at intervals to form maculae. Walls of mesopores
and zooecia vestibules amalgamated. Median tubuli present be-
tween the median laminae. Superficial apertures circular, sur-
rounded by a sloping area. Interspaces flat between the meso-
pore apertures.

Type and only known species-: H. bi folia Ulrich. Chester
group.

BBYOZOA. 405

DESCRIPTIONS OF SPECIES.

PROTOCRISINA Ulrich.

(For generic diagnosis see page 369).

PROTOCRISIXA EXIGTJA Ulrich.*

PI. XXIX, flg. 4-4c, and PL T.TTT, fig. n-iie.

Zoarium ramose; branches slender 0.6 mm. wide, 0.3 to 0.45
mm. thick, dividing dichotomously at a very acute angle afc in-
tervals varying from two to seven mm. Celluliferous side
strongly convex, smooth, with four, occasionally only three,
series of zooecia. Reverse faintly convex, flattened or slightly
concave in the central part, finely striate, the striae often
minutely granulose. Zooecia subtubular, thin-walled within, with
prominent tubular mouths. Apertures subcircular, 0.09 mm. in
diameter, five or five and one-half in two mm. vertically: ar-
ranged in oblique rows. A small number of circular pores, 0.04
mm. in diameter are scattered over both the reverse and cellu-
liferous faces.

Position and locality*. — This species is rare at Wilmington,
111., where it is associated with typical Cincinnati group fossils.
It is more common and in a better state of preservation in
Trenton group strata at Montreal, Canada, and Trenton Falls,
X. Y.

This form can scarcely be regarded as more than a variety of a rather common
Trenton group species, in New York and Canada, where it is generally identified with
the form to which Hall applied the name of Gorgonia ? perantiqua (Pal. N. Y., vol. I,).
This identification is probably erroneous since neither the figures nor the description
agree with the specimens. These consist of numerous rigid, remotely bifurcating
branches, which are spread upon a plane about their own width apart, with four rows
of pores. 4 Hall says the branches are "lax" and carry two laterally opening rows of
cells. Under these circumstances it seems to me better to propose a new name for the
species than to perpetuate what is obviously an error.

406 PALAEONTOLOGY OF ILLINOIS.

PHACELOPORA Ulrich.

(For generic diagnosis see page 368.)

PHACELOPORA PERTENUIS Ulrich.

PI. XXIX, flg. l-lc.

Zoarium articulated ; exceedingly slender, consisting of numer-
ous, elongate conical segments, arranged in linear series. Often
two segments are developed instead of one, when the zoarium
is diehotomously branched. Zooecia tubular, compressed coni-
cal, suboval in transverse section, with an average width of
0.12 mm., arranged in pairs, each pair constituting a segment;
apertures contracted, circular, about 0.06 mm. in diameter.
Sutures between zooecial tubes more sharply impressed on the
anterior side than on the posterior where the minute axial tube
is situated. Segments 0.6 to 0.8 mm. long, 8-shaped in cross-
section just below the apertures; here the lateral diameter is
from 0.2 to 0.25 mm. and the smaller about 0.15 mm., while
at the proximal extremity of each segment the diameter is only
0.07 mm. Segments are developed from the minute axial tube.

This very interesting bryozoan is so unique, that no compar-
isons are required. Its thread-like zoarium is readily over-
looked.

Position and locality: — Upper beds of the Trenton group.
Thebes, 111. Rather rare, associated with several species of
Nematopora and Crinoids.

PHACELOPORA CONSTRICTA Ulrich.

PI. XXIX. flg. 2.

Of this species I have seen only the fragment figured. This
consists of five short segments, having each the appearance of
being set into the expanded upper end of the one preceding it.
The segments vary slightly in length, but do not exceed 0.3 mm.;
the diameter expands from about 0.13 mm. below, to 0.25 mm.,
or a little less, at the apertures. Each is composed of five
(possibly six) subcylindrical zooecial tubes, the sutures being
sharply impressed, and most of the slightly contracted circular
apertures apparently closed by a convex lid. The diameter of

BRYOZOA. 407

the aperture is about 0.07 mm., that of the zooecial tube just
beneath the aperture a little less than 0.1 mm.

Position and locality: — The specimen came from the upper
beds of the Trenton group in Central Kentucky.

MONTICULIPORA d'Orbigny, 1849.

(Prod. Pol., p. 25.)
(For generic diagnosis see page 370.)

The genus Monticulipom was founded by the distinguished
French naturalist, d'Orbigny, for the reception of four charac-
teristic species of the Lower Silurian rocks about Cincinnati,
Ohio. Of these, M. mammulata, being the first species to follow
the generic diagnosis, is universally regarded as the type. The
original descriptions are so meagre that palaeontologists are
compelled to rely upon Edwards and Haime's identification of
the species. These authors give good figures of three of the
species, and of the fourth (M. filiosa) a description only. As all
four of the species are common and marked by easily recog-
nized external characters, collectors have had little difficulty in
identifying them.

The genus, as defined and used by me, is founded upon M.
mammulata and does not include any of the other species de-
scribed by d'Orbigny. His M. ramosa belongs to Callopora,
M. filiosa to Leptotrypa, or, possibly, Monotrypa; and M. fron-
dosa to Heterotrypa. In this restricted sense Monticulipora
can, of course, include only a small proportion of the large
number of Bryozoa that have from time to time been referred
to the genus. It is only another instance showing the absolute
necessity of clearly describing and illustrating the minute charac-
ters, both external and internal, of the typical species of all
genera. At least sixteen species are known to me having the
essential characters of M. mammulata. Of this number only
nine have been described, the remainder being new and awaiting
opportunities for proper publication.

Position and locality: — So far as known, the genus is first
met in Trenton strata, but before the close of the Lower Silurian
age, i. e., the deposition of the Cincinnati group, it had already
reached the culminating point in its development, since only a
single species, the M. wmchelli from the Hamilton group of
Michigan, is known from rocks of later date.

408 PALEONTOLOGY OF ILLINOIS.

MONTICULIPORA LAMELLOSA UMch.

PI. XXXII, fig. 4-4fc.

Zoarium large, growing upon some foreign object, composed
of one or more layers, each from one to four or five mm. in
thickness; the type specimen is a large mass composed of six
or seven layers. Surface smooth, showing the surface projec-
tions of the acanthopores. Walls of zooecial tubes thin, of about
the same thickness throughout, though a little thickened at the
surface. Zooecia, except just at their origin, direct, about eight
in two mm., angular; their apertures also angular. Diaphragms
numerous, horizontal, from one-half to their own diameter
apart. Cystiphragms few, never arranged in series. Acantho-
pores moderately numerous, increasing in size toward the sur-
face.

Cystiphragms are rarely detected in sections of this form, yet
the general facies of this species and especially the granular
nature of the walls, leave little doubt as to its being a member
of the genus Monticulipora,.

Position and locality: — Cincinnati group, Wilmington, 111.

MONTICULIPORA WINCHELLI Ulrich.

PI. XLV, flg. 6-tia.

Zoarium consisting of a number of superimposed layers, the
whole from two to twelve mm. in thickness, the layers from one-
half to two mm. thick. Under surface provided with a coarsely
wrinkled epitheca. Upper surface showing slightly elevated
clusters of larger cells, about 4 mm. apart, measuring from
center to center. Walls of zocecia rather thin. Zooecia angular,
irregularly hexagonal, those of the normal size seven or eight
in two mm., those in the clusters from one-third to one-half
larger. Apertures angular. Cystiphragms closely set, very large,
leaving but a small visceral cavity; occasionally infundibular.
Acanthopores apparently wanting.

Owing to the large crescentic shape and closeness of the cysti-
phragms, vertical sections present appearances which at first
sight are very puzzling. The tubes seem to be tabulated very
differently. This is due to the shape of the Cystiphragms and
their not being arranged in the same way in all the tubes. A

BRYOZOA. 409

vertical section of the zoarium cuts a few tubes through the
•••-liter but most of them at a greater or less distance from it.
< )uly when the section passes through the extremely small visceral
cavity, is the usual overlapping appearance of cystiphragrns
>hown. and the narrow visceral cavity seen to be crossed by
diaphragms. When the section does not pass through the vis-
ceral cavity, and it rarely does, the diaphragms seem curved or
horizontal and to extend clear across the tube. The appear-
ance presented by cutting through an infundibular cystiphragm
i- shown at the top of the third tube from the right, in figure
6a of plate XLV.

The general features of the zoarium are decidedly like those
of several Lower Silurian species of the genus. The large size
of the cystiphragms. the consequent slenderness of the visceral
cavity, and the apparent absence of acanthopores, are marked
peculiarities of the species.

Position and locality:— Hamilton group, Thunder Bay. Mich.

HOMOTRYPA Ulrich, 1882.

•Jour. Cin. Soc. Nat. Hist, Vol. V, p. 240.)
(For generic diagnosis see page 370.)

Already ten (?) species belonging to this genus have been de-
scribed, yet this is scarcely one-half of the species known to me.
The Cincinnati group furnishes the largest proportion of them,
and. like Monticulipora, only one species is known to have ex-
isted at any subsequent period. The characters of the genus
are remarkably persistent and nearly always easily recognized.

HOMOTRYPA ARBUSCULA Ulrich.

PI. XXXVIH, fig. 3. 3 e.

Zoarium loosely attached to foreign bodies by a broad basal
expansion, from which grow a number of stout dendroidal
stems with freely inosculating branches. Stems diminishing
from twelve mm. in diameter at the base to three or four at
the free terminations. Surface smooth, with scarcely noticeable
clu.-ters of larger cells. Cell apertures oblique, angular and
sliirhtly elongated, varying in diameter from the average of
0.18 or 0.20 mm., to 0.3 mm., the diameter of those in the
—51

410 PALAEONTOLOGY OF ILLINOIS.

clusters. When well preserved, the cells have their margins
beset with very small granules, which may be only surface or-
namentations, as no evidences of acanthopores have yet been
detected in tangential sections. Walls of zooecial tubes slightly
flexuous and crenulate, very thin in the axial region and but
little thickened in the peripheral region. Zooecial tubes oblique
throughout their course, with an unusually gradual curve from
their origin to the surface. Apertures seven or eight in two
mm. A few mesopores with diaphragms somewhat less than
their diameter apart are developed in the cortical region. One,
occasionally two, cystiphragms are developed in the zooecial
tubes in the transition period.

In the case of complete specimens, the growth alone will easily
separate this species from similar forms. Fragments are readily
distinguished by the thin walls, and more than usual obliquity
of the cell apertures from any Lower Silurian species known to
me. In the brevity of the pheripheral region this species is like
H. dawsoni Nicholson, but the frondescent growth and pro-
nounced monticules of that species give it an entirely different
appearance.

Position and locality: — Birdseye horizon of the Trenton group,
High Bridge, Ky.; Calhoun Co., and near Dixon, 111.

HOUOTRYPA GELASINOSA UMch.
PL XXXII, fig. 2-2d.

Zoarium consisting of flattened branches, four mm., more or
less, in thickness. Surface without monticules, but marked with
conspicuous, elongated, parallel, dimple-like maculae, arranged
in transverse rows. Walls of zooecia thin, and flexuous or wavy
in the axial region, moderately thickened near the surface.
Zooecia subangular, about ten of the ordinary size in two mm.,
those forming the borders of the maculae about one-half larger.
Mesopores angular, comparatively large and shallow, present
in the dimples only. Diaphragms occasionally present in the
axial region. Cystiphragms rather closely set. In the meso-
pores there are two or three diaphragms in the space of a tube
diameter. Acanthopores commonly situated in the angles of

BRYOSOA. 411

the zooecia, sometimes found in the axial region; now and then
they do not follow the trend of the zooecia in the cortical re-
gion, but cut across the tubes at an acute angle. The acantho-
pores found in the maculae are longer and larger than the
others. In some parts of a longitudinal section, the acantho-
pores are seen to have exceedingly thin cross partitions.

The elongated dimples distinguish this species from all other
described forms of the genus. An undescribed related form, oc-
curring in the Cincinnati group, at Waynesville, Ohio, also has
somewhat similar elongated dimples, but differs in other char-
acters.

Position and locality: — Cincinnati group, Wilmington, 111.

HOMOTRYPA FLABELLARIS UMch.
PI. XXXII, flg. 3-3c

Zoarium consisting typically of fan-shaped fronds; an almost
perfect specimen gives the following measurements: width 45
mm., height 50 mm., thickness 5 mm. Surface smooth, with
obscure maculae about four mm. apart, measuring from center
to center. Peripheral portion of zoarium narrow. Walls of
zooecial tubes flexuous or crenulated in the axial region,
and very thin even in the cortical region. Zooecia apertures
angular, slightly oblique, from eight to ten in two mm., those
in the maculae from a third to a half larger than the average.
Mesopores few, gathered into clusters in the maculae. Zooecial
tubes provided with a few remote straight diaphragms in the
axial region. Diaphragms moderately numerous in the meso-
pores. Cystiphragms form a short series in each tube. Acan-
thopores few, very small.

A very close variety occurs in the upper beds of the Cincin-
nati group, at Blanchester, Ohio, which has the maculae a little
more pronounced, and a tendency to a ramose growth. The
thin walls and flabellate growth distinguish H. tiabellaris from
the hitherto described species of the genus.

Position and locality: — Cincinnati group, Wilmington, 111.

412 PALEONTOLOGY OF ILLINOIS.

HOMOTRYPELLA Ulrich, 1886.

(14th Ann. Eep. State Geol. Minn. p. Si.)
(For generic diagnois see page 370).

This genus was established to receive a small but natural
group of species that could not be included in any of the other
genera of the family. The ramose habit of growth ally the
genus to Homotrypa Ulrich, but the abundant mesopores are
a distinguishing mark of some importance. A comparison with
Peronopora Nicholson, and Atactoporella Ulrich, shows the fol-
lowing differences: the zoaria of the first are bifoliate, of the
latter parasitic; in both the cystiphragms are developed in an
almost uninterrupted series to the zooecial apertures. In the
structure of the walls the typical species presents close resem-
blance to Peronopora, while that of H. context a, shows greater
likeness to Atactoporella. The aggregate of characters thus in-
dicate an intermediate position between Homotrypa on the
one side, and Peronopora and Atactoporella on the other.

HOMOTRYPELLA CONTEXTA Ulrich.

PI. XXXII. flg. 5-5b.

Zoarium consisting of a mass of irregular, coalescing branches
varying in thickness from three to six mm. Surface smooth,
exhibiting spaces where both zooecia and mesopores are larger
than ordinary. Walls of zooecia scarcely thickened in the cor-
tical region. Zooecia sub-circular or oval, from eight to ten in
two mm., about 0.15 mm. in diameter, occasionally in contact,
ordinarily separated by the angular, thin-walled mesopores,
which are very numerous and differ but little in size from the
zooecia. Diaphragms few in the axial region, but becoming-
more numerous as the zooecial tubes approach the peripheral
region. Here they are abundant, extending from the overlap-
ping cystiphragms to the opposite wall of the tube. In the
mesopores the diaphragms are closely set, and approximately
upon the same level in all, two or three in the space of a tube
diameter. Acanthopores rather small, but a conspicuous feature

BRYOZOA. 413

in tangential sections, situated in the walls of the zocecia, from
three to five surrounding each zooecium; also at some of the
angles between the mesopores.
Position and locality: — Cincinnati group, Wilmington, 111.

HETEROTRYPA Nicholson, 1879.

(Pal. Tab. Corals p. 291.)
(For generic diagnosis see page 371.)

As defined by Dr. Nicholson this genus included very diverse
material, the only characters common to the assemblage being
the possession of two sets of cells (i. e. zooecia and mesopores). In
the "Am. Pal. Bry." I have shown that only one of the seven-
teen species which he refers to the genus is congeneric with the type
species. H. froiidosa d'Orb., (H. mamniulata Xich., non d'Orb).
The remaining fifteen species are distributed among the genera
Callopora, Homotrypa, Amplexopora (?), Monotrypella, Bato-
stoina and Batostonwlla. The amended definition of the genus
as then proposed by me is now somewhat modified by the eli-
mination of H. vaupeli, which I now refer to Nicholsonella.
The restricted group is closely allied to Dekayia Ed. & H., and
comprises at least nine species, all of them from the Cincinnati
group. Three of these remain undescribed.

HETEROTRYPA PROLIFICA Ulrich.

PI. xxxvn, fig. i-id.

Zoarium frondescent, or subramose with much flattened
branches, varying in thickness from four to twelve mm., and at
times attaining a height of ten cm. Low rounded tuberosities
arranged in irregularly interesecting lines and composed of cells
a little larger than the average, commonly surrounding a clus-
ter of mesopores. serve to break up the monotony of an other-
wise smooth surface. Zocecial tubes curving in the axial region,
direct throughout the peripheral region, where their walls be-
come considerably thickened. Zooecia apertures sub-polygonal,
about eight in two mm., and 0.15 to 0.18 mm. in diameter.
Interspaces occupied by calcareous matter: where very wide by
a few mesopores with illy defined walls. Most of the mesopores
are found in the clusters. A few diaphragms in the axial re-

414 PALEONTOLOGY OF ILLINOIS.

gion; in the transition period they become more numerous; in
the cortical region they are close-set, a tube diameter or less
apart. In the outer portion of this region they are often con-
cave, sometimes tending to the infundibular form. Mesopores
more closely tabulated than the zooecial tubes. Acanthopores
a little more than one-third as numerous as the zooecia; when
not situated at the angles, generally inflecting the zooecial
cavity a little.

This species approaches quite closely to H. frondosa d'Orb.,
having a somewhat similar growth; but in that species the
zooecia are more angular, the walls thinner, mesopores far more
numerous and the acanthopores rather more abundant.

Position and locality: Cincinnati group. A common form
in the upper beds at Blanchester, Ohio. It also occurs at Wil-
mington, 111. The H. frondosa is restricted to the lower half
of the Cincinnati group.

HETEROTRYPA INFLECT A Ulrich.

PL XXXVII, fig. 2rZd.

Zoarium frondescent, seldom over four cm. in width, six cm.
in heighth, and five mm. thick; usually only about three in
thickness. Surface smooth or with slight elevations of cell aper-
tures somewhat larger than the average. Zooecial tubes bend-
ing abruptly into the cortical region, with walls slightly flexu-
ous in the axial region. Zooecia apertures circular, 0.14 to
0.18 mm. in diameter, with about eight in two mm. A large
but variable number of angular mesopores scattered among
the zooecia, rather more numerous in the clusters. Diaphragms
only one or two in each zooecial tube; numerous in the meso-
pores. Acanthopores present in considerable numbers, frequently
indenting the visceral cavity, in well preserved specimen^ very
conspicuous on the surface, giving it a hirsute appearance.

This species is distinguished externally from H. frondosa
D'Orbigny, its nearest ally, by its much more delicate growth,
strictly frondescent form, monticules wanting or but little ele-
vated, conspicuous acanthopores and larger number of meso-
pores. Internally it has very few diaphragms, wrhich structures
are abundant in M. frondosa.

Position and locality: — Cincinnati group, Cincinnati, Ohio.

BRYOZOA. 415

HETEROTRYPJL SINGULARIS Ulrich.

PL XXSVU. Bg. 3-8f.

Zoarinm subramose, at times attaining a thickness of seven
cm. Surface smooth, or nearly so, with clusters of cell aper-
tures a little larger than the average. Zooecia about nine in
two mm., angular and thin-walled in the axial, subeircular in
the mature region. There are commonly two or more succes-
sions of immature and mature regions. Mesopores of variable
size, very numerous, usually angular or subcircular. Dia-
phragms developed very irregularly, at times but few in the
cortical region and wanting in the axial, at other times about
two tube diameters apart in the axial and elosewset in the peri-
pheral region. They are commonly horizontal, often concave,
sometimes infundibular, and occasionally simulate cystiphragms
if they are not of that nature. Acanthopores very numerous,
inflecting the visceral cavity so as to give it a petaloid appear-
ance.

The extremely large size of this species, the remarkable de-
velopment of acanthopores and mesopores, and irregular char-
acter of the diaphragms are its leading features. Some points
in its structure leave me in doubt as to this being its rightful
position, but for the present it seems best to place it with
Heterotrypa.

Position and locality: — Cincinnati group, Wilmington, HI.

DEKAYIA Edwards and Haime, 1850.

(PoL Foes, des Ten-. Pal. p. 277.)
{For generic diagnosis see p. 371.)

Extensive remarks upon the position of this genus, as well as
full descriptions of a number of species, will be found in my

Amer. Pal. Bry."* to which I refer the reader. D. aspera, Ed.
HL, the typical species, occurs in rocks of the Cincinnati group,
near Wilmington, Dl. The specimens are in a bad state of pre-
servation, but I had no difficulty in identifying them by means
of thin sections. The following species is the only one known
from rocks above the Lower Silurian.

•Jour. On. Soc. Sat. Hist. VoL VL pp. 84 and 146-155.

416 PALEONTOLOGY OF ILLINOIS.

DEKAYIA DEVONICA Ulrich.

PI. XLV, flg. 5-5d.

Zoarium ramose, consisting of small subcylindrical irregular
branches, averaging six or seven mm. in thickness; in one in-
stance solid, in all the others hollow with a AArrinkled epitheca
lining the interior; in the latter the zoarium has a thickness of
less than 1 mm. Surface level or with slightly elevated clusters
of larger apertures and bristling with very prominent spines 1
mm. or a little less apart. Zooecia angular, quite oblique to
the surface, thin-walled throughout, about five in two mm.,
measuring longitudinally, with elongated, unequal apertures.
Diaphragms few, one, or perhaps more to a tube. Acanthopores
exceedingly prominent, with very thick walls.

The examples from New York are hollow and appear to be
composed of one or more very thin layers. The specimen from
the Ohio Falls has a solid axis. The extreme obliquity of the
zooecial tubes and the very strong acanthopores distinguish this
form from any Devonian bryozoan known to me.

Position and locality: — Devonian; Falls of the Ohio; Eighteen
Mile Creek, N. Y. (Hamilton group).

CALLOPORA Hall, 1852.

(Pal. N. T. vol. H, p. 144.)
(For generic diagnosis, see page 372.)

This is a distinct and easily recognized genus, and so far as
known, its range does not extend into Devonian deposits, but
in all the groups of rocks between the Trenton limestone and
the Lower Helderberg, inclusive, it is represented by from one
to twelve species. In all, twenty species have been studied, but
only thirteen of them are described. The first species to follow
Hall's generic description is his C. elegantula, from the Niagara
group afc Lockport, N. Y. According to commonly accepted
rules of nomenclature, the species must stand as the type of
the genus. Of the remaining species which Hall described and
referred to the genus in 1852, C. aspera and probably C. floridn
and C. lammata belong to Leioclema as now understood; while
C. nummiformis is very likely referable to Calloporella. With

BRYOZOA. 417

the exception of C. perelegans none of the species more recently-
referred to Callopora by Prof. Hall seem to have the essential
characters of the genus.

Thin sections of Callopora exhibit a remarkable uniformity
of structure, and it is sometimes very difficult to discriminate
between those of closely allied forms. TJiis uniformity is more
especially apparent in transverse and vertical sections, but as
these are highly diagnostic of the genus, they are necessary to
confirm the generic reference. Most of the species form large
bushy masses, and the Cincinnati group deposits often furnish
some very showy cabinet specimens.

CALLOPORA SUBXODOSA Ulrich.

PI. XXXIII, fig. 5-5c.

Zoarium ramose: stems subcylindrical, from six to twelve
mm., or even more in diameter. Surface sometimes nearly
smooth, usually tubercled. Tubercles rounded, never conical,
more or less elevated, composed of apertures rather larger than
the average, and numerous mesopores. Zooecial walls com-
paratively thin throughout. Zooecia approaching the surface
in a gentle curve, about seven in two mm.; with circular aper-
tures, ranging from 0.18 to 0.27 mm. in diameter; surrounded
by a variable number of angular or subcircular mesopores.
The zooecial tubes expand very gradually from the point of
their origin until they attain their normal size. In the first
part of their course, they have several diaphragms about their
own diameter apart: after that, diaphragms become rare and
may be entirely absent in the rest of the zooecial tube. The
mesopores are tabulated very closely throughout; about three
diaphragms in a space equalling their own diameter.

This species differs from the common C. ramosa d'Orbigny
in the less prominent monticules, which are rounded instead of
conical. The tabulation of the tubes in the two species is also
very different. Though very distinct from (_'. elegantula Hall,
the type of the genus, it is more nearly related to that form
than is any other known species of the genus.

Position and locality: Upper beds of the Cincinnati group,
Blanchester. <).. and numerous other localities. A variety oc-
» -iirs at Wilmington and Savanna, 111.
—52

418 PALEONTOLOGY OF ILLINOIS.

CALLOPOKELLA Ulrich, 1882.

("Amer. Pal. Bry." Jour. Tin. Soc. Nat, Hist. Vol. V. p. 154.)
(For generic diagnosis, see page 373.)

The thick ring-like walls of the zooecial tubes distinguish this
genus from Diplotrypa Nich., species of which C. harrisi Ulr.,
the type, resembles in other respects. The species next de-
scribed is only provisionally placed in the genus as better pre-
served material may show that it is not congeneric with C.
harrisi.

CALLOPORELLA? NODULOSA Ulrich.

PI. XXXIII, ng. 4-4a.

Zoarium parasitic upon foreign bodies, (so far as observed
upon the valves of Strophomena,} forming patches of greater
or less extent; edge of zoarium inclined to turn up. Surface
marked with small conical monticules, a little more than two
mm. apart, measuring from center to center, more or less sub-
solid at the apex, due to the closure of the mesopores, and ar-
ranged in diagonally intersecting rows. Apertures circular,
about nine in two mm., 0.2 mm. or a little less in diameter.
Interspaces occupied by mesopores which are most numerous
in the monticules.

The internal structure has not been observed owing to the
peculiar character of fossilization which has preserved the ex-
ternal features, but entirely obliterated the internal structure.
Hence the species is referred only provisionally to Calloporella.
The general external appearance is that of Atactoporella or-
toni Nich., but it wants the petaloid apertures of that species.

Position and locality: Cincinnati group, Savanna, 111.

TREMATOPORA Hall, 1852.

(Pal. N. Y. Vol. II. p. 149.)
(For generic diagnosis, see page 373.)

This genus was re-defined by me in my "Amer. Pal. Bry."
taking T. tuberculosa, Hall, the first species to follow Prof.
Hall's generic description, as the type. Much redistribution of

BRYOZOA. 419

species is the unavoidable result, since but a small proportion
of the forty-two American species that had been previously re-
ferred to the genus are really congeneric with the typical form.

TREMATOPORA DEBILIS Ulrich.

PL XXXIV. flg. 3-3e.

Zoarium consisting of slender, cylindrical, branching stems,
from 1.5 to 2 mm. in diameter. Surface smooth. Zooecial tubes
long, bending but little to reach the surface. Cell walls very
thin in the axial region, slightly thickened in the cortical region.
Zocecia with apertures circular or nearly so, about 0.15 mm. in
diameter, and surrounded by a peristome most elevated at the
lower end; closer together transversely than longitudinally,
there being about five in one direction and only four in the
other in 1 mm. Mesopores interspersed irregularly among the
cells, of unequal size, and closed at the surface. Acanthopores
few and inconspicuous. An occasional diaphragm is present in
in the zocecial tubes, and from one to three in the mesopores.
The cortical region, as shown by a transverse section, is very
narrow.

From TV? nitida Or., this species is distinguished by its more
robust growth and larger and differently shaped cells. The
cortical region is thinner, and the curve of the zocecial tubes in
approaching the surface is greater in this species. From T.
primigenia Ulr., a Trenton species of Minnesota, it is easily dis-
tinguished by the lack of the maculae so characteristic of that
species. It differs too widely from the other described species of
the genus to necessitate comparison.

Position and locality: — (?) Cincinnati group, Alexander Co.,
Illinois.

TREMATOPORA? NITIDA Ulrich.

PL XXXIV, fig. 2-2f.

Zoarium consisting of small cylindrical stems, branching vari-
ously, 1 mm. or less in diameter. Zooecial tubes extending
obliquely outwards from the center of the stem, scarcely curving

420 PALEONTOLOGY OF ILLINOIS.

to reach the surface. Walls thin in the axial region, thickened
but little towards the surface. Zooecia often in contact, with
apertures sometimes oval, usually pyriform, narrowing above,
surrounded by a narrow peristome, obsolete or less distinct at
the upper end; about six or seven in the space of one mm.
measuring longitudinally, and eight to ten measuring trans-
versely, arranged in irregular, obliquely ascending lines. Inter-
stitial spaces irregular, more or less depressed, apparently solid
at the surface, but in thin sections seen to be occupied by
elongated mesopores. Acanthopores moderately abundant,
small, sometimes conspicuous. Diaphragms two or three in the
mesopores, rarely present in the zocecial tubes.

This species is associated with a number of other small forms,
from all of which it is readily separated by its very much
smaller cells, and characteristic pear-shaped openings. This is
probably the smallest species of the genus. Its small size and
pyriform apertures at once distinguish it from its nearest con-
geners T. debilis and T. primigenm Ulr.

Since the above was written a large series of specimens of
this species have been collected. These show that the base of
the branches was pointed and that the zoaiium was jointed at
irregular intervals. It is, therefore, probable that the species
belongs to another genus.

Position and locality:— Cincinnati group, at Savannah, 111.,
where it is very abundant at an horizon about 150 feet above
the river.

TREMATOPORA CALLOPOROIDES Ulrich.

PL XXXIV, flg. 1-ld.

Zoarium irregularly ramose, branches from four to seven mm.
in diameter. Surface marked by faint monticules whose centers,
occupied by sub-stellate groups of mesopores with closed aper-
tures, present an apparently solid aspect. Distance between
centers of monticules two or three mm. Zocecial tubes run
irregularly in the a.xial region, curve gradually, and at the sur-
face are almost direct. Walls thin in the axial region and but
little thickened in the cortical region. Zooecia seven or eight in
the space of two mm., with sub-angular or sub-circular aper-

BRYOZOA. 421

tures. Peristome faint. Interspaces occupied by very thin-
walled, angular mesopores, which are sometimes open at the
surface. When this is the case, the surface resembles that of
some species of Callopora. From four to seven diaphragms are
developed in the zooecial tubes as they leave the axial region.
Diaphragms numerous in the mesopores. Acanthopores small
and usually inconspicuous, often projecting a little into the
zooecial cavity owing to the thinness of the walls.

The characters of this species are so distinct from T. debilis
with which it is associated, and from other species of the genus
that comparisons are unnecessary. Its surface bears some re-
semblance to certain species of Callopora, but the internal struc-
ture is widely different.

Position and locality: Cincinnati group, Alexander County,
Illinois.

NICHOLSONELLA Ulrich.

(For generic rliagnosis see page 374.)

Only four or five species are known having the peculiar
characters upon which this genus is founded. Two of these, N.
ponderosa, the type of the genus, and an undescribed species,
are from the Trenton limestone, the other two or three from
the Cincinnati group. Of the latter, N. vaupeli was described by
me as a species of Heterotzypa* It is not uncommon near
the tops of the hills at Cincinnati, Ohio. A closely allied species
or variety occurs about 250 feet higher in the series and is
bundant at several localities in Ohio. The fourth form is
described here for the first time. It also belongs to the Cin-
cinnati group, but is not yet known from any other locality
than Wilmington, 111.

The affinities of Nicholsonella, are with Constellaria Dana, but
the absence of stellate maculae, is quite sufficient to distinguish
them. The frondescent species resemble Heterotrypa Nich., but
the relationship is much more remote than I at one time
thought.

The generic name is given in honor of Dr. H. Alleyne Nichol-
son, as a slight token of my appreciation of the great value of

*Jour. Cin. Soc. Nat. Hist., voL VI, p. 85.

422 PALEONTOLOGY OF ILLINOIS.

his labors, in micropalseontology. To him belongs the credit of
being the first to make extensive use of the microscope in classi-
fying the "Monticuliporidse."

NICHOLSON ELL A PONDEROSA Ulrich.

PL XXXIV. Figs. 5-5d.

Zoarium large, consisting of very irregular, inosculating, flat-
tened branches or fronds, from one to two and one-half cm. in
thickness. The largest example is twelve cm. in height. Surface
even, exhibiting rather inconspicuous maculae in which the
zooecia are slightly larger and separated by wider interspaces
than usual. Zooecia curving rapidly from the axial region to
the surface, where they open with regularly arranged circular
apertures, about 0.21 mm. in diameter; eight in three mm.
Peristome very faint, carrying from eight to twelve small
granules. Interspaces either appearing solid and minutely granu-
lose, or showing the angular mouths of a single row of rather
large mesopores; in the maculae there are two rows. In the
spaces between the maculae, the zooecia apertures are separated
by interspaces varying in width from 0.1 to 0.2 mm. Mesopores
are developed in moderate numbers already in the axial region.
Diaphragms not very numerous, being most so in the peripheral
region, where they are distant from each other from one to
nearly three tube-diameters. In the mesopores they are thick,
and about their own diameter apart.

The large flattened branches and irregular growth distinguish
this species from all Bryozoa known to me from this horizon.
It is much larger than N. vaupeli Ulr., from the Cincinnati
group, while N. cumulata, differs decidedly in structure and
zoarial habit.

Position and locality: Trenton group, Dixon, 111.

I am indebted to Dr. Everett for two good examples. Some
smaller subramose specimens from near Beloit, Wis., may be-
long to this species but their preservation is such that I could
not satisfy myself of their identity.

BKYOZOA. 423

NirHOLSONELLA (TMTLATA
PL XXXm, Fig. 6-6c.

Zoarium very irregular, sometimes submassive, at other times
subramose, consisting of one or more superimposed layers, from
0.7 to 4 mm. in thickness, with the inner side generally covered
by an epithecal membrane or loosely attached to other bodies.
In one (a lobate mass having a tendency to become massive)
the central regions are solid in the sense that the tubes traverse
an ''axial region." Surface sometimes smooth, but generally
with low, rounded, rather regularly arranged monticules, two
mm. or a little more apart, measuring from center to center. On
these monticules the zooecia are scarcely larger than those in
the intermediate spaces, but they are separated by wider inter-
spaces. Zoopcial tubes slightly curved near the origin in each
layer, after which they proceed direct to the surface. In this
portion they are crossed by diaphragms from once to twice
their diameter apart. Apertures subcircular, the average dia-
meter 0.18 mm. ; when perfect with a faintly elevated and
minutely spinulose margin; about seven in two mm.; arrange-
ment moderately regular. Interspaces varying in width, usually
narrow, usually almost half as wide as the zooecia, occupied
by small, closely tabulated, angular mesopores, which, just be-
neath the aperture surface of each layer, are filled with a dense
deposit. The minute mural tubuli, best shown in this deposit,
are a less marked feature than in the more typical species.

The habit of growth d'stinguish the species from both N.
ponderosa and -V. raupeli. The absence of stellate maculae dis-
tinguish specimens from an associated species of Constellaria,
that is closely allied to C. limit aris Ulr.

Position and locality: Cincinnati group, Wilmington, Illinois;
very abundant.

CONSTELLARIA Dana, 1848.
(Zoophytes, p. 537.)

(For generic diagnosis see page 374.)

The type of this genus is my C. tiorida* For many years it
was regarded as identical with Stellipora antheloidea Hall, and

*Jour. Cin, Soc. Nat. Hist, Vol. V, p. 257. and VoL VI, p. 267.

424 PALAEONTOLOGY OF ILLINOIS.

the New York types of that species seemed to have been lost
sight of entirely. Several years ago having had an opportunity
of examining Hall's original specimens, together with another
set of authentic examples, I came to the conclusion that the
Cincinnati specimens belonged not only to another species, but
to a distinct genus as well. In 1848 Dana proposed the genus
Constellaria for the Cincinnati species, but failed to give it a
specific name, and, as I have said till recently, it has gone cur-
rent as either Constellaria or Stellipora antheloidea. In 1875,
Nicholson described and figured a closely allied but distinct
species under the name Constellaria polystomeUa\ . Examples of
this species are not uncommon at several localities in Ohio and
Indiana, where the upper layers of the Cincinnati group are
exposed. The species also occurs at an equivalent horizon in
Wisconsin and Illinois, but has not been found at Cincinnati.
As it differs both internally and externally from the Cincinnati
species, I could not accept Mr. Whitfield's proposition to apply
Nicholson's name to all the western^ forms, but considered my-
self justified in applying the new name florida to the common
Cincinnati species.

The genus as defined by me includes at least five species and
several varieties, all of them from the Cincinnati rocks. What
may prove another species, closely allied to C. linntaris, occurs
at Wilmington^ 111.

CONSTELLARIA PARVA Ulrich.

PL XXXIV, Figs. 1-lb.

Zoarium consisting of irregularly undulating small fronds, two
to three mm. in thickness, and twenty-five mm. or more in
height, growing from a broad basal expansion. Surface smooth,
showing small star-shaped maculae of the type characteristic of
the genus, varying from one to one and one-half mm. apart,
measuring from center to center, and averaging sixty in the
space of ten mm. square. Zooecial walls comparatively thin
throughout, though ring-like in the mature region. Zooecial

tPal. Ohio, Vol. II. p. 215.

tGeol. of Wis., Vol. IV, p. 251, 1882.

BRYOZOA. 425

tubes bending rather abruptly from the axial to the per-
ipheral region, about 0.08 mm. in diameter in the spaces be-
tween the stars, while the two to six zocecia between the
rays of the macula* are slightly larger, sometimes having a
diameter of 0.13 mm.; apertures circular, with peristome. The
angular, thin-walled mesopores are arranged in star-shaped
macula*, and in the intermediate spaces surround the zooecia in
one or two series: they vary in size being generally smaller than
the zocecia, and largest at the center of a macula. Diaphragms
from one-half to one tube diameter apart in the peripheral
region of the zocecial tubes, and from one to two tube-diameters
apart in the axial region; very crowded and apparently upon
the same level in contiguous mesopores.

This species resembles C. fischeri Ulr., but forms smaller and
thinner fronds, and has diaphragms throughout the zooecial
tubes; the disproportion in the size of the two sets of tubes is
much less, the zocecia are smaller, and a greater number of
mesopores is found surrounding the zocecia in this species.

Position and locality: Cincinnati group, Wilmington, 111.

LEIOCLEMA Ulrich, 1882.

"Am. Pal. Bry." Jour. Cin. Soc. Nat. Hist. Vol. V. p. 141.)
(For generic diagnosis see page 376.)

When this genus was proposed I was acquainted with the
type species, Callopora punctata Hall, only. Now, by extend-
ing the limits, fifteen species are united under the name. Five
are here described as new. the remainder, with one exception,
having been previously described by Prof. Hall as species of
Callopora. It is possible that more than one generic group is
included in the genus as now defined, but, as I found no char-
acters upon which to base satisfactory divisions, I have thought
it advisable to arrange them provisionally as one generic group.
The species are distributed as follows: L.? wilmingtonense Or.,
in The Cincinnati group; L. singulare, asperuw, floridum, and (?)
laminatum of Hall in the Niagara group; L. cellulosum, para-
siticum. and ponderosum of Hall, in the Lower Helderberg
group: L. occidens (Fistulipora occidens Hall and \Vhitfield)m the
Hamilton group; L. wachsmuthi and subglobosum Or., in the
—53

426 PALEONTOLOGY OF ILLINOIS.

Kinderhook group; L. gracillimum Ulr., in the Burlington and
Keokuk groups; L. punctatum Hall, and L. foliatum Ulr., in
the Keokuk group, and L.? araneum Ulr., in the Chester group.
Beside, several undescribed species are known, one from the
Hamilton, one from the Keokuk, one from the Chester, and
another from the Coal Measures.

LEIOCLEMA WILMINGTONENSE Ulrich.

PL XXXIV. flg. 4-46.

Zoarium compressed, subramose; the type specimen is about
twenty-two mm. in width and about ten mm. in thickness,
surface smooth, unmarked by maculae, or monticules. Zooecial
tubes slightly inclined from the vertical in the center of the
branch, and reach the surface by a rather sharp curve; pro-
vided with a few diaphragms near the cortical region. Walls
but little thickened in the peripheral portion. Zooecia about
four to one mm. Apertures of zooecia circular, about 0.2 mm.
in diameter, seldom in contact, being nearly always completely
surrounded by angular mesopores, which are almost as large
as the zooecia. Diaphragms numerous in the mesopores, from
0.05 to 0.10 mm. distant from one another. Acanthopores
small and inconspicuous.

Some care is required to distinguish this species from the some-
what similar Hoinotrypella contexts, which is associated with
it and, like it, has thin-walled zooecia separated by large meso-
pores. Sections at once prove the distinctness of the two forms,
the species here under consideration being entirely devoid of the
cystiphragms which are so abundant in H. context a. The
nearest congener of this species is the L. occidens Hall and
Whitfield.

Position and locality: Cincinnati group, Wilmington, 111.

LEIOCLEMA OCCIDENS Hall and Whitfield.

Fistulipora occidens H. & W. 23 Beg. Eep. State Mus. N. Y., p. 228. PL V, flg.9, 10; 1875.

Callopora cincinnatiensis Ulrich. Jour. Cin. Soc. Nat. Hist. Vol. I, p. 93, PL IV,
fig. 8-86, 1878; Ibid. Vol. V, p. 142; PL VI, flg. 18-18a, 1882.

Zoarium exceedingly variable in form, commonly irregularly
ramose or lobate. Surface smooth, occasionally (in exception-

BRYOZOA. 427

ally well preserved specimens) minutely spinulose; but this is
never a conspicuous feature. Walls of zooecia thin, somewhat
flexuous in the axial region, slightly thickened in the peripheral
region. Apertures of zooecia circular from 0.15 to 0.20 mm. in
diameter, seven or eight in the space of two mm.; encircled by
a single series of large angular or subcircular mesopores, on an
average about two-thirds the size of the true zooecia. Diaphragms
rather few and remote in the zocecial tubes, in the mesopores
more numerous, and about their diameter or more apart. Acan-
thopores small, present in moderate numbers, and at times en-
croaching a little upon the zooecia.

Aside from L. minutum (?) Rominger, the nearest congener of
this species is L.? wilmingtonense from Silurian strata. These
species have a facies rather different from the other species of
this genus, and should perhaps form a separate genus. In that
case L. subglobosum, and possibly L. wachsmuthi as well, will
go with them.

Small examples of this species have been described by the
author as Callopora cincinnatiensis. The specimens were fur-
nished him by Mr. Fred Braun, who stated that he had col-
lected them from strata of the Cincinnati group, at Cincinnati,
0. This is now known to be an error, and careful comparison
with Iowa examples leaves no doubt as to their having been
collected at some western locality.

Position and locality: Hamilton group. Occurs abundantly
at several localities in Iowa; (Independence, Rockford and Buf-
falo); also at Rock Island, 111.

LEIOCLEMA MIXUTUM Rominger?.

tFistxlipora minnta, Rominger, 1866. Proc. Acad. Nat. Sci. Phila. p. 120.
Callopora minntissima Nicholson, 1875. Rep't. Pal. Ontario, p. 77, fig. 43.

This common species of the Hamilton group, closely resembles
the preceding in its minute structure, and it would be difficult to
point out any differences between them, excepting that of zoar-
ial habit. L. minuta, so far as observed, invariably occurs as
thin incrusting layers, a mm. or less in thickness, that by su-
perimposition of successive layers may eventually form small
masses. Such specimens are more common in the western lo-
calities than in Michigan and Canada.

428 PALAEONTOLOGY OF ILLINOIS.

The species is identified with authentic examples of the spe-
cies, agreeing in most respects with Rominger's brief descrip-
tion. The interspaces are, however, not vesiculose, but occu-
pied by unmistakable mesopores, with open apertures. The
structure, therefore, is not as in Fistulipora. Should an exam-
ination of Rominger's original types prove his species distinct,
then Nicholson's name will stand.

Position and locality: Common at Buffalo and Davenport in
Iowa, Andalusia and Rock Island, in 111., and at several locali-
ties in Northern Michigan and Western Ontario.

LEIOCLEMA WACHSMUTHI Ulrich.

PL LXXV, flg. 7. 7b..

Zoarium a thin expansion, consisting of one or more super-
imposed layers, each one mm. or less in thickness; the lower
surface provided with a finely wrinkled epithecal membrane.
Surface irregularly undulating or montiferous, occasionally
showing a tendency to throw up short, slender branches, from
one to two mm. in diameter. Zocecia about six in the space of
two mm. with thin walls, at first prostrate, then curving and
opening perpendicularly to the surface. Apertures mostly oval,
some circular, their longer diameter about 0.2 mm.; their mar-
gins beset with small spinules, the surface projections of the
acanthopores which occasionally project into the visceral cavity
and give the aperture a floriform aspect. Mesopores angular,
very numerous, completely encircling the zocecia in from one to
three rows.

The thin laminar growth, and the exceeding abundance of the
mesopores are the most marked features of this species.

Position and locality: Kinderhook group, Marshalltown, la.

LEIOCLEMA SUBGLOBOSUM Ulrich.

PL LXXV, fig. 8, 8b.

Zoarium subglobose, pedunculate, base sometimes expanded.
Surface smooth. Zooecia radiating out in curved lines in all
directions from the center of the base. Tube walls thicken in-

BRYOZOA. 429

appreciably as they near the surface. Zooecia eight or nine in
the space of two mm., with circular or oval apertures 0.15 to
0.2 mm. in diameter. Zooecia separated by angular or subcir-
cular mesopores arranged in a single or double series, some-
times forming small clusters. Mesopores from one-half to three-
fourths as large as the zooecia. Diaphragms fairly abundant
throughout the zooecial tubes, very numerous and closely set in
the mesopores. Sections present obscure evidences of the dia-
phragms of the mesopores having a central perforation. Acan-
thopores numerous and of large size.

The figure of the tangential section (PI. LXXY. fig. 8b) does
not represent the structure as well as it might. Some of the
acanthopores are made too prominent and others overlooked
entirely. This is due to the peculiar fossilization by which the
internal characters are much obscured. The globose form in
connection with the strong tabulation easily distinguish this
species from the other species of the genus.

Position and locality: Kinderhood group. Marshalltown. la.

LEIOCLEMA GRAciLLmrM Ulrich.

PI. LXXV, fig. 6, 6b.

Zoarium ramose, branching regularly; branches from one to
one and a half mm. in diameter. Surface even. Apertures of
zooecia elliptical, about 0.15 mm. in their longer diameter, and
0.1 mm. in their shorter diameter, eight or nine in two mm.;
surrounded by a large number of very small mesopores. Acan-
thopores small, numerous.

This species is closely allied to L. punctatum, but is distin-
guished from it by its smaller cells, and smaller branches, which
are also more constant in size. It seems to have an extended
vertical range. The typical form is from the Keokuk group.
Specimens which cannot be distinguished from the typical forms
are found in the Kinderhook. Burlington and Warsaw groups.

Position and locality: Occurs at most localities of the Keokuk
group: in the Kinderhook group at Marshalltowu. la: in the
Burlington group at Burlington, Iowa, and in the Warsaw beds,
at Warsaw. 111.

430 PALEONTOLOGY OF ILLINOIS.

LEIOCLEMA PUNCTATUM Hall.

Callopora punctata Hall. 1868. Geol. Iowa, Vol. I, part II. Pal. p. 653.
Callopora missouriensis Kominger, 1866. Proe. Aead. Nat. Sci. Phila. p. 117.
Leioclema punctata Ulrich, 1882. Jour. Cin. Soc. Nat. Hist. Vol. V. p. 141.
PL VI, fig. 1, la.

Zoarium ramose, reaching a height sometimes of fifteen to
twenty cm., branches from two to five, generally about four
mm. in diameter, springing from a broad irregular basal ex-
pansion, which may be free and with a wrinkled basal epitheca
or attached to foreign bodies. Surface smooth or slightly
tubercled, in well preserved specimens, spinulose, having a hir-
sute appearance under a pocket lens. Walls of zooecia flexuous
in the axial region, comparatively thick in the peripheral region.
Zooecia about five or six in the space of two mm., with sub-cir-
cular, or petaloid apertures, from 0.15 to 0.2 mm. in diameter.
Mesopores sub-angular, small, their diameter about one-third
that of the zooecia, arranged in two or three or more series
about the zooecia, frequently aggregated into large irregular
groups, comparatively more numerous on the basal portion
than higher up on the zoarium. Diaphragms strong, few and
remote in the zocecial tubes, more numerous and about their
own diameter apart in the mesopores. Acanthopores large and
numerous, from four to seven encircling the zooecia and en-
croaching upon their visceral cavity, causing the floriform ap-
pearance of the zooecia observed in tangential sections and
upon the surface.

The robust habit of growth distinguishes this species from L.
gracillimum. The great abundance of mesopores and acantho-
pores, in connection with the growth, separates it from all other
species of the genus.

Position and locality: This is the most abundant species in
the Keokuk limestone, occurring at Keokuk and other localities
in Iowa; Warsaw 111.; Lagrange, Mo. (Rominger); and King's
Mountain, Ky. Also in the Warsaw beds.

BRYOZOA. 431

LEIOCLEMA FOLIATUM Ulrieh.

(Fig. 1, page 301.)

Zoarium a delicate laminar expansion, from one-half to one
and a half mm. in thickness, with a thin wrinkled epitheca on
the under surface. Upper surface even, spinulose, with a hirsute
appearance. Zooecia, except at their origin, direct, with thin
walls, about six in the space of two mm. Apertures circular,
petaloid, about 0.2 mm. in diameter. Mesopores small, angu-
lar or subcircular, arranged in a single, occasionally a double
row about the zocecia. Diaphragms thin, few and remote in
the zooedal tubes, rather more than their own diameter apart
in the mesopores, sometimes apparently wanting even in these.
Acanthoporcs very large and prominent, usually three, some-
times four, surrounding each zooecium and projecting more or
less into its cavity.

The laminar form, less numerous acanthopores, and compara-
tively small number of mesopores. distinguish this species from
the L. punctatum, occurring in the same beds.

Position and locality: Warsaw beds, Warsaw, 111.

LEIOCLEMA? ARAXEUM Ulrieh.

PL LXXV, Fig. *-3c.

Zoarium consisting of a thin crust, about one-half mm. in
thickness, attached to foreign bodies, sometimes throwing up
small, short branches. Surface generally even, sometimes marked
with small, pointed tubercles. Zooecia arranged radially about
one or more centers; at first prostrate, soon proceeding directly
to the surface, nine or ten in the space of two mm., sometimes
in contact, at other times separated by mesopores. Apertures
oval, their longer diameter scarcely 0.2 mm. Mesopores small,
irregular in shape, frequently compressed between the zooecia,
scattered about rather promiscuously, commonly aggregated
into clusters, which are often elevated into conical monticules,
appearing subsolid at the surface. Diaphragms closely set in
the zooecial tubes, about three in the space of a tube diameter,
a little more closely set in the mesopores. Acanthopores very
small, situated in the wall of the zooecium, with from seven to
ten encircling each zouecium.

432 PALEONTOLOGY OF ILLINOIS.

Different examples show considerable variation in the number
of mesopores. The most marked features of this species are the
tenuity of the zoarium, the small size of the zocecia, the com-
paratively small number of mesopores, the large number and
extreme minuteness of the acanthopores, and the nearly equal
tabulation of zooecial tubes and mesopores. It prefers to attach
itself to the shells of Brachiopoda, though it is found adherent
to other organisms as well.

Position and locality: Monroe Co., 111.; Chester, 111.; Pulaski
and Jackson Co., Ky.; and probably at all typical localities of
the Chester group.

BATOSTOMELLA Ulrich, 1882.

(Jour. Cin. Soc. Nat. Hist. Vol. V, p. 141 and 154).
(For generic diagnosis see page 375.)

This genus attained its maximum and most typical develop-
ment during Carboniferous time. With perhaps three or four
exceptions, the Silurian and Devonian species present peculiari-
ties which, when once we have a good understanding of this
group of fossils, may necessitate their removal to other genera.
The two species next described belong to these doubtful forms,
but the four following them are typical members of the genus.
A small portion of a tangential section taken from an unusu-
ally well preserved example of B. gracilis is figured on plate
XXXV, fig. 2. It should be compared with the sections of B.
obliqua figured on plate XLVI.

BATOSTOMELLA SIMULATRIX Ulrich.

PI. XXXV, flg. 1-10.

Zoarium dendroidal, throwing off cylindrical branches from
two to five mm. in diameter. Surface smooth, with clusters not
at all or but slightly elevated, in which the interspaces between
the cells are wider and mesopores more abundant than elsewhere.
Zooecial tubes a little irregular in their course in the axial por-
tion, quite oblique in the peripheral zone where their walls be-
come considerably thickened. Apertures of zooecia oval, owing
to the obliquity of the tubes, about 0.2 mm. in their longer
diameter and about eight in two mm. measuring longitudinally.

BRYOZOA. 433

Zoopcial tubes for a short distance after their origin rather
closely tabulated, afterwards the diaphragms become about two
tube diameters or less apart. Mesopores moderately abundant,
with rather close-set diaphragms. Acanthopores very small.

In the oval form of the cells, the numerous mesopores, the
frequent closure of the cell apertures by perforated opercular
structures, this species is remarkably like Callopora sigillaroides
Nich., but its internal structure is altogether different. Intern-
ally it can scarcely be distinguished from B. trentonensis Nich.,
from the Trenton limestone of Ontario, but the smaller size of
this species, and its rather more oval apertures and different
horizon discriminate the form from that.

Position and locality: Cincinnati group, Savanna, 111., and at
a number of localities in Ohio and Indiana, where the upper
beds of this formation are exposed.

BATOSTOMELLA OBLIQUA Ulrich.

PL XLVL fig. 2-2c.

Zoarium dendroidal, consisting of dichotomously and other-
wise branching stems, of an average thickness of six mm. Sur-
face marked with low rounded tubercles composed of larger
sized cell apertures; centers of clusters 2.5 mm. apart. Zooecial
tubes slightly tortuous, opening very obliquely upon the sur-
face, their walls thin and somewhat flexuous in the axial re-
gion, rather thick in the cortical zone. Both tangential and
vertical sections show that the central portion of the wall is
granular. Apertures angular, eldngated, owing to their obli-
quity, those occupying the monticules especially so, about seven
in two mm. measuring lengthwise. Mesopores few or wanting.
Two or three diaphragms developed just before the tubes enter
the peripheral region. A few faint and small acanthopores ap-
pear to be present in tangential sections; not observed on the
surface.

The great obliquity of the tubes, the absence, more or less

complete, of mesopores, and the angular elongated apertures

are the most distinctive characters of this form. The granular

structure of the central portion of the walls is the chief ground

—54

434 PALEONTOLOGY OF ILLINOIS.

for placing; this species under Batostomella. This peculiar struc-
ture is present in well preserved examples of B. gracilis James,
as figured on plate XXXV, fig. 2.

Position and locality: Hamilton group, Alpena, Michigan.
The specimens from which this description is drawn were kindly
donated to the author by the Rev. W. H. Barris, of Davenport,
Iowa.

BATOSTOMELLA INTERSTINCTA Ulrich.

PI. LXXV, fig. 4-4c.

Zoarium forming a very thin incrustation, spread upon crinoid
columns, throwing up irregularly branched shoots, one mm.
or thereabouts in diameter at the basal portion, and somewhat
more higher up. Surface smooth; when well preserved hirsute.
Zooecial tubes make a very abrupt bend from the axial to the
peripheral region. Apertures varying from circular to oval,
about nine in two mm., measuring along the irregular obliquely
ascending intersecting rows of apertures. In the thin basal ex-
pansion the interspaces are less wide, and there are fewer meso-
pores. Here the average long diameter of the oval apertures is
about 0.18 ram., while upon the ramose portion the diameter
of the mostly circular apertures rarely exceeds 0.1 mm. A
considerable number of mesopores are developed upon the ra-
mose portion. Diaphragms few or wanting. The cortical re-
gion is equal in thickness to about the diameter of the axial
region, the most marked peculiarity of this species and one
which at once distinguishes it from all other species of the genus.

The irregular growth, large basal expansion, and its larger
cell apertures, readily distinguish this species from B. spinulosa.

Position and locality: St. Louis group; rather rare at Pella,
Iowa.

BATOSTOMELLA SPINULOSA Ulrich.

PI. LXXV, fig. 1-le.

Zoarium slender, ramose, branching at greater or less inter-
vals, the cylindrical stems from one to two mm. in diameter.
Surface smooth; when well preserved, hirsute. Zooecial tubes
thick-walled and direct in the cortical region after making a
rather abrupt turn from the axial region where they are thin-

BRYOZOA. 435

walled. Zooecial apertures separated by thick interspaces, oval,
variable in size, the average long; diameter being 0.1 mm., six
or seven in two mm., measuring lengthwise. Mesopores small,
moderately abundant, circular or broadly oval. Diaphragms
often wanting in the zooecial tubes, never numerous; generally
lacking in the mesopores. Acanthopores very numerous, arranged
in a circular band about each zocecium.

The peculiarities of tabulation, the thick walls, and vast num-
ber of acanthopores, causing the spinulose aspect of the surface,
are the most noticeable features of this species.

Position and locality: Chester group. Abundant at Sloan's
Valley, Pulaski Co., and other localities in Kentucky; worn
specimens from Chester, 111., are referred doubtfully to this
species.

BATOSTOMELLA ABRUPTA Ulrich.

PI. LXXV, fig. 2-2e.

Zoarium dendroidal, from two to three mm. in diameter. Sur-
face smooth, hirsute, with clusters of somewhat larger cells.
Zooecial tubes inclining gently outwards from their origin, rather
oblique even in the cortical region, causing the apertures to
have a somewhat oval shape. Apertures about eight in two
mm. When in a good state of preservation the apertures are
surrounded by a sloping space. The thick interspaces are oc-
cupied by one or two rows of closely arranged small acantho-
pores. When in two series, they are separated by a groove in
which an occasional mesopore of small size may be detected.
Walls of zooedal tubes abruptly thickened in the unusually nar-
row cortical region. An occasional diaphragm developed in the
zooecial tubes.

The somewhat more robust growth, very narrow cortical
region, the larger cells, and the abruptly thickened walls, are
the principal points which distinguish this species from B. spinu-
losa, found in the same beds.

Position and locality: Chester group, Sloans Yalley, Pulaski
Co., Ky. Probably occurs at Chester and other localities in
Illinois.

436 PALEONTOLOGY OF ILLINOIS.

BATOSTOMELLA NITIDULA Ulrich.

PI. LXXV, flg. 3-3&.

In this species the zoarium consists of very slender branching
stems, about one mm. in thickness. Surface even, hirsute. Cell
apertures oval, variable in size, the largest about 0.15 mm. in
their longer diameter; about eight in two mm., with only mod-
erately thick interspaces. Often the cell aperture is provided
with an .opercular structure having a central perforation.
Zocecial walls frequently flexuous in the axial region, consider-
ably and abruptly thickened in the cortical zone. Mesopores
moderately abundant. Diaphragms almost wanting. A single
row of acanthopores encircles each zooecium.

This species holds an intermediate position between B. spinv-
losa and B. abrupta. The greater irregularity in branching,
the larger cell apertures, less numerous acanthopores, greater
obliquity of zocecial tubes in the axial region, thinner inter-
spaces and other points separate it from B. spinulosa. The
comparatively wider cortical region, thinner interspaces, fewer
acanthopores, and more slender habit of growth, distinguish it
from B. abrupta.

Position and locality: Chester group; Chester, 111., and Sloan's
Valley, Ky.

STENOPORA Lonsdale, 1845.

(Strzelecki's Phys. Desc. N. S. Wales, p. 09.)
(For generic diagnosis see page 375.)

Like the genera Chaetetes and Monticulipora this genus has
for many years served as the receptacle for very diversely con-
structed Palaeozoic Bryozoa. We owe it to the labors of Dr. H.
A. Nicholson and Mr. B. Ethridge, Jr., that we now possess
some adequate idea of the true structure of the genus, these
naturalists having published a short time ago critical descrip-
tions and figures of Lonsdale's types* together with several
new species.

The present addition to our knowledge of Stenopora makes
it abundantly evident that the genus has no affinities with the
FAVOSITID^E, but that in Batostomella on the one hand, and

* Ann. and Mag. Nat. Hist, Vol. IV. 1879, and Vol. XVII, 1886.

BRYOZOA. 437

Anisotrypa on the other, we see the closest possible relations.
Going a little farther we arrive by easy gradations into most
close proximity to such undoubted Bryozoa as Rhombopom.
Indeed in practice it is not an easy task by any means to draw
the line between these genera, though the typical forms appear
to differ widely. It will require nothing less than a rnonograph-
ical study to determine the exact limits of each division.

STENOPORA AMERICANA Ulrich.

PI. LXXIV, fig. 1-la.

Zoarium ramose, branches large, subcylindrical, irregularly
divided, twenty-five to forty mm. in diameter, and twelve cm.
or more in height. Usually they are very much flattened by
pressure, and appear to be frondescent. Surface sometimes
smooth, generally marked by somewhat elevated, broad tuber-
cles, whose summits are about four mm. apart. Zooecia with
rounded or polygonal apertures varying according as the in-
terspaces are thick or thin; those on the monticules a half
larger than the others; nine or ten of the ordinary size in three
mm. Zooecial tubes thin-walled and vertical in the axial region,
then bending rapidly outward proceed direct to the surface; as
they enter the peripheral region their walls gradually exhibit the
moniliform thickenings characteristic of the genus. These soon
become more pronounced and the intervals shorter. Near the
surface five to eight occur in two mm. Diaphragms horizontal,
perforated. Mesopores absent or very few. Acanthopores of
moderate size, fairly abundant, giving to the well preserved sur-
face a spinose aspect.

Position and locality: Keokuk group; Warsaw, and Jersey
Co., 111. Not uncommon.

var. VARSOVIENSIS Ulrich.

PI. LXXIV, fig. 3, 3a.

This variety has smaller zooecia and much thicker walls than
the typical form. The moniliform thickenings of the walls are
also less distinct from each other. The specimens are from
Warsaw, 111.

438 PALEONTOLOGY OF ILLINOIS.

STENOPORA MONTIFERA Ulrich.

PI. LXXIV, fig. 4-4b.

Zoarium consisting of thin laminae, which sometimes appear
to have been part of large hollow branches. Surface with large
and very prominent monticules. Zooecia eight to ten in three
mm.; generally with very thin walls and angular apertures. Re-
maining external features like those of S. americana, of which
it may be only a good variety.

The internal structure of these specimens differs slightly from
that of typical S. americana, the periodic thickening of the
walls being more irregular, and the divisional line between the
zooecia marked by a closely arranged series of minute dark
spots, which are also to be detected in vertical sections.

Position and locality: Keokuk group, Otter creek, Jersey Co.,
111.; Bentonsport, Iowa, and other localities.

STENOPOBA EMACIATA Ulrich.

PL LXXIV. Fig. 2-2a.

Zoarium laminar, attaining a considerable width; thickness
one mm. or more; under surface provided with a thin wrinkled
epitheca. Surface marked with groups of larger cells, which are
elevated into low broad monticules, about four mm. apart,
measuring from center to center. Apertures polygonal, varying
in width from 0.3 mm, in the intermacular spaces, to 0.5 in the
clusters, about eight or nine in three mm. Walls very thin,
spinose at the angles. Zooecial tubes bending toward the sur-
face very soon after their origin. Walls very thin throughout,
but appreciably thickened at intervals, about seven times in two
mm. Mesopores wanting. Perforated diaphragms very thin, a
tube diameter or so apart. Acanthopores small, excepting in
the clusters of large cells, commonly at the angles, protruding
more or less into the zocecial chambers.

The very thin walls and more numerous diaphragms distin-
guish this species from S. montifera. S. tuberculata Prout,
differs somewhat in growth, and has the walls more decidedly
thickened and at shorter intervals. The diaphragms are also
more numerous.

Position and locality: Keokuk group; Warsaw, 111., and
Keokuk, Iowa.

BRYOZOA. 439

STENOPORA INTERCALARIS Ulrich.

PL LXXIY, Fig. 5-5a.

Zoariura consisting of large cylindrical branches from one to
two cm. in diameter. Surface smooth, without groups of larger
cells. Zooecia polygonal, somewhat variable in size, apertures
subangular, 0.18 to 0.25 mm. in diameter, about ten in three
mm. Interspaces moderately thick, with spines at the angles
when the surface is well preserved. Walls of zooecia thin and
faintly flexuous in the axial region, thickened and irregularly
moniliform in the cortical region, the beads not separated by
thin intervals, but merged into each other. Mesopores quite
numerous for the genus, small, but varying in size, circular or
angular, intermittent and irregular. A few diaphragms developed
in the outer part of the axial region, generally^ absent in the
cortical region. Acanthopores numerous, invariably situated at
the angles of junction.

This species differs from S. americana, with which it is asso-
ciated, in having no monticules nor clusters of large cells,
smaller cell apertures, far greater number of mesopores (which
may be detected on the surface) and much fewer diaphragms.

Position and locality: Keokuk group, Warsaw, HI.

STENOPORA AXGULARIS Ulrich.

PI. LXXIV, Fig. 6-6b.

Zoarium consisting of extremely massive branches, the largest
specimen under investigation being eight cm. wide and four cm.
thick just before a bifurcation, the latter measurement being
about equivalent to the normal diameter of the branches. Sur-
face smooth but with group of cells decidedly larger than the
average. Apertures angular, variable in form, with thin inter-
spaces, about ten in three mm. Walls of tubes thin in the axial
region, and but very little thickened in the cortical though pre-
serving the moniliform character of the genus. In the cortical
region the zocecia do not form continuous tubes, but the whole
is divisible into a number of distinct thin Ia3^ers. Mesopores
very few. Diaphragms wanting. Acanthopores abundant and
commonly occupying the angles, not very large, but conspicuous
on account of the tenuitv of the walls.

440

PALEONTOLOGY OF ILLINOIS.

Its large size, comparatively small angular cells, absence of
diaphragms, and very thin walls, are characters which, com-
bined, easily distinguish the species from others of the genus.

Position and locality: Keokuk group, Lagrange, Mo.

STENOPORA INTERMITTENS Ulrich.
\

Fig. 16. Sections of Stenopora inter-mittens Ulr., x!8.

a.— tangential section showing extremes in the thickness of the walls, a few perforated
diaphragms, and the conspicuous acanthopores ; ?>.— vertical section showing the faintly
beaded struc ure of the walls, and the intermittent development of the acanthopores.

Zoarium an irregular broad expansion, presenting a very
rough aspect. Lower side with a strong epitheca. Upper sur-
face very irregular in its general contour, but exhibiting faintly
elevated broad monticules, occupied by cells scarcely larger than
the average. Apertures angular, quite regularly polygonal, often
quadrate, between seven and eight in two mm. The zoariuin
seems to be composed of a number of superimposed layers.
The zooecial walls are very thin till near the termination of the
layers when they are moderately thickened, and numerous, ex-
ceedingly strong acanthopores are abruptly developed. Perfo-
rated diaphragms occur sparingly, and the walls occasionally
show long narrow swellings.

The peculiar growth, thin walls, and intermittent character of
the zoarium, are the most marked features of the species.

Position and locality: Keokuk group, Warsaw, 111.

BRYOZOA. 441

STENOPORA TUBERCULATA Prout.

Fluatra tuberculata Prout. 1859. Trans. St. Louis, Acad. Sci. Vol. I. p. 447.
Cyclopora polymorpha Prout. 1860. Trans. St. Louis Acad. Sci. Vol. l,p. 578.
C'vclopora polymorpha Prout. 1866. Geol. Sur. 111. Vol. II, p. 421. PI. XXI. fig. 5,5b.
PI. XVII, fig. 3— 3f.

Fig. 17. Sections of Stenopora tuberculata Prout x!8.

(i. — Tangential section; l>.— Vertical section showing thickness of layers and tabula-
tion of zooecial tubes.

Zoariuni aii expanded crust attached to Brachiopoda and
other organisms, frequently attaining a large size by superim-
posing of numerous thin layers; sometimes hemispherical, dis-
coidal, or laminar, and apparently free, with a rugose epitheca
upon the lower side. Surface smooth or with faintly marked,
scarcely elevated, clusters of cell apertures but little larger than
the average. Apertures polygonal, quite regularly arranged,
about ten of the average size in three mm., separated by thin
interspaces, spinose at the angles. Zooecial tubes for a short
distance prostrate, then curving rapidly to proceed direct to the
surface of the layer. Walls thin, somewhat flexuous, often dis-
tinctly moniliform. A few mesopores may occur near the center
of the clusters mentioned. Diaphragms abundant, perforated,
from one-half to their diameter apart. Acanthopores abundant
of moderate size, often encroaching upon the visceral cavity.

The variable form of growth, thicker walls and more numer-
ous diaphragms, discriminate this species from S. emaciata,
while the more decidedly moniliform walls, thinner zoarial layers,
slightly larger zooecia, and smaller acanthopores, separate it
from S. cestriensi*. I cannot distinguish from this species
Prout's Cyclopora polymorpha, described from the Chester
group and propose to unite them as above.
—55

442 PALEONTOLOGY OF ILLINOIS.

Position and locality: Chester group, Chester and numerous
other localities in Illinois; also common in the Warsaw beds,
which furnished the original examples of the species, and in the
St. Louis limestone.

STENOPOEA CESTRIENSIS Ulrich.

PI. LXXIV, flg. 7,7a.

Zoarium forming laminar expansions of considerable breadth,
the under surface provided with a thick concentrically wrinkled
epitheca. The typical example consists of but a single layer
with an average thickness of about five mm. Celluliferous surface
spinulose where well preserved, with low broad tubercles occu-
pied by cell apertures slightly larger than the average; cen-
ters of monticules three or four mm. apart. Zocecial aper-
tures sub-circular or polygonal, about eleven in three mm. Im-
mature portion of zocecial tubes short, prostrate, bending
rather quickly and proceeding direct to the surface. Walls
thickened, but seldom appearing distinctly moniliforrn, the
swellings usually being merged into each other. Divisional line
between zocecia sharply defined. Mesopores probably absent.
Diaphragms abundant, close set, five or six in one mm. Cen-
tral perforation large, often closed with a flat or concave plate.
Acanthopores numerous, rather large, usually situated at the
angles and bulging a little into the zocecial cavity. They ap-
pear more than usually conspicuous in tangential sections, being
sharply defined and the dark central spot comparatively large.

This species is related to S. tuberculata Prout, but the cells
are smaller, their individual walls more clearly defined, the
acanthopores more conspicuous, and the zooecial layers at least
twice as thick.

Position and locality: Chester group, Chester, 111.

STENOPORA RAMOSA Ulrich.

PI. LXXIII, flg. 6, 6c.

Zoarium ramose, consisting of cylindrical or somewhat com-
pressed stems from five to ten mm. in diameter. Surface usu-
ally even but marked with clusters of cells a little larger than

BRYOZOA. 443

the average. Zooecial apertures angular or sub-circular, fre-
quently preserving the perforated opercula. separated by thin
interspaces, about nine or ten in three min. Zooecial tubes pro-
ceeding in a very gradual curve to the surface where they are
almost direct. Walls of zocecia very thin and flexuous in the
axial region, considerably thickened in the peripheral region
where they are more or less regularly moniliform, the swellings,
however, not separated by very thin intervals. Divisional line
between adjoining zocecia generally well defined. Diaphragms
horizontal, with a sub-central perforation, having a thickened
margin, rather more than one-half their diameter apart, devel-
oped mainly in the cortical region. Mesopores oval, very few.
Acanthopores of moderate size, situated generally at the angles,
occasionally projecting into the zooecial cavity.

Sections of a single example show what may be rather large
communication pores. In tangential sections the}' appear as
simple transverse lines of lighter color than the walls. In ver-
tical sections they are again represented by narrow light inter-
vals, traversing the walls in a direction parallel with the A-
shaped layers of sclerenchyma.

Position and locality: Chester group. Common at Sloan's
Valley. Pulaski Co.. and other localities in Kentucky. Several
illy preserved specimens from Chester, Illinois, are supposed to
belong here.

*.-

STENOPORA MEEKANA Ulrich.

PL LXXm, Fig. 7-7a.

Zoarium ramose, consisting of robust branches, fifteen mm. or
more in diameter. Surface without monticules but marked with
clusters of cell apertures about one-third larger than the aver,
age size. Apertures angular, with thin interspaces, about nine
of the ordinary size in three mm. Zooecial tubes curving gradu-
ally from the axial region, direct in the peripheral region.
Walls thin and irregularly flexuous in the axial region, thick-
ened and more or less moniliform in the cortical region. Divi-
sional plane between adjoining zooecia, marked by lighter colored
tissue or a dark line. A few thin diaphragms are developed as
the tubes approach the mature region. Here[they are somewhat
thicker, and <•]« about two-thirds of a tube diameter

444 PALAEONTOLOGY OF ILLINOIS.

apart, and, as usual, perforated subcentrally. Mesopores very
few or wanting. Acanthopores not very large, numerous, almost
all the angles being occupied.

The far more robust habit of growth, larger number of a.can-
thopores, and somewhat thicker walls, are peculiarities which
, easily distinguish this species from S. ramosa,. In other re-
spects they are practically identical, and I do not doubt that
they have been developed from a common type.

Position and locality: Chester group, Chester, 111.

STENOPORA RUDIS Ulrich.

PI. LXXII, Fig. 8-8b.

Zoarium consisting of hollow irregular branches, varying
in size and composed of one or several superimposed layers,
each 1.5 mm. or less in thickness. Surface smooth, but with
well marked, scarcely elevated, clusters of cells, about one-half
larger than the average size. Apertures polygonal, those
of the average size 0.3 mm. in diameter, and eight in 3
mm. Zooecial tubes oblique and thin walled at first, then making
an abrupt bend, proceed directly to the surface, the walls at
the same time becoming much thicker. One to three bead-like
swellings succeed the first. Two to five perforated diaphragms
intersect the tubes of each layer, the first occurring at the
point where the tubes bend outward. Rather small acanthopores
occupy less than half of the angles of junction between the
zocecia. Divisional line between the walls of adjoining zocecia
well marked.

This species makes a close approach to Anisotrypa, but the
acanthopores ally it rather more closely with Stenopora. Sec-
tions have a general resemblance to those of S. polymorpha
Prout, but the zocecia are larger and the acanthopores less
numerous. The hollow branches and large cells distinguish it
from the Keokuk species of the genus.

Position and locality: Chester group. Sloan's Valley, Pulaski
Co., Ky.

BRYOZOA. 445

STEXOPORA CARBON ARIA Worthen.

PL LXXm, Fig. 8-8a.

Ch(f fetes ? carlonaria Worthen. 1875. Geol. Sur. El.. VoL 6, p. 526. PL XXXII, Fig. 5.
Stenopora carbonaria Foerste, 1887. BulL ScL Lab. Denison Univ., VoL 2, p. 85. PL
VHI, Fig. 13a-c.

Zoarium ramose, consisting of sub-cylindrical branches, vary-
ing in diameter from ten to fifteen mm. Surface smooth, not
exhibiting groups of cells marked by differing from the average
size. Zooecial apertures angular and sub-circular, with either
thick or thin interspaces, about ten or eleven in three mm.
Walls of zooecial tubes moniliform in the cortical region, the
swellings irregular, often merged into each other, at other times
separated by a thin interval; twelve to fourteen in two mm.
Thin centrally perforated diaphragms developed in the mature
zooecia and about a tube diameter apart; none were observed in
the axial region. Mesopores almost wanting. Acanthopores
large, fairly numerous. The divisional line between the thick-
ened portions of the walls of adjoining zooecia is marked by a
series of minute dark spots.

The above describes the typical form of the species. Associated
with them are a number of other specimens offering certain
peculiarities that, while not very marked, are nevertheless suffi-
cient for identification. These I propose to designate as varie-
ties maculosa and confer! a.

var. MACTLOSA Ulrich.

PI. LXXTTT, Fig. 10-lOa.

This differs from the typical form in having well-marked
groups of small cells, surrounded by zooecia apertures of larger
size than the average. Nine or ten of the ordinary size in three
mm. The diaphragms are also stronger and more numerous.
The branches too are generally somewhat stronger, being some-
times as much as twenty-five mm. in diameter.

446 PALAEONTOLOGY OF ILLINOIS,

var. CONFERTA Ulrich.

PL LXXIII, Fig. 9-9a.

This variety has the beads of the moniliform walls more
closely set, there being in the peripheral region ten or eleven in
one mm. The moniliform character of the walls is more pro-
nounced in this variety than in any other form of the genus
known to me, excepting S. ohioensis Foerste, lately described
from the base of the Coal Measures in Ohio. Should it prove
upon further examination that the var. conferta is identical
with the Ohio form, then Mr. Foerste's name will take prece-
dence over mine.

Position and locality: Coal Measures; both the varieties and
the typical form, occur at Caseyville, 111. I have also studied
examples from Ohio, and from Lawrence, Kansas.

STENOPORA? SIGNATA Ulrich.

PI. LXXIII, fig. 5, 5b.

Zoarium consisting of branching cylindrical stems, from four
to seven mm. in diameter. Surface hirsute, without monticules
Zocecial apertures small, sub-circular or sub-polygonal, varying
in diameter from 0.15 to 0.25 mm.; about seven in two mm.
Interspaces moderately thick, minutely granulose between the
strong acanthopores which occur at many of the angles. Zooecial
tubes curving gradually from the center of the axial region to
the surface, where they are direct. Walls thin in the axial re-
gion, considerably and irregularly thickened in the cortical re-
gion, never distinctly moniliform. Diaphragms entirely wanting.
Acanthopores very large, about one to every two zooecia. Sec-
tions present a peculiar feature. In tangential sections, for in-
stance, the zocecial cavity is surrounded by a single series of
very minute dark spots. Along the middle of the partition be-
tween the zooecia the same kind of spots form closely arranged
stellate clusters, of five or more, while a single series again
surrounds the acanthopores. In vertical sections these peculiar
spots are closely arranged in transverse series and less regu-
larly in vertical rows. At the surface they appear as granules.
I am unable to offer a satisfactory explanation of these singu-
lar structures. It is possible, however, that they represent the

BRYOZOA. 447

foundations of delicate setaB. Similar structures have been de-
tected in Bactropora simplex and in species of Rhombopora (e. g.
R. crassa.) The minute dark spots between the walls of the
zocecia in S. montifera and other species of the genus are prob-
ably of the same nature.

The generic reference of the species is somewhat doubtful, and
there is little danger of confounding it with any species of
Stenopora known to me. The large acanthopores serve amply
in distinguishing specimens from Rhombopora crassa Ulrich, an
associated form.

Position and locality: Coal Measures. The only examples
seen are from Casey ville, 111.

ANISOTRYPA Ulrich, 1883.

(Jour. Cin. Soc. Nat. Hist. Vol. VI, p. 275.)
(For generic diagnosis see page 376.)

When I proposed this genus I supposed the hollow branches
and the large cell which occurs at sub-regular intervals among
the ordinary zocecia of A. symmetrica, were characters of gen-
eric importance. My acquaintance with Stenopora Lonsdale,
and Rhombopora Meek, at that time also was limited. Now,
since I have gone over the ground much more fully, I find that
both features are really of only specific importance. That I
failed to grasp the more significant characters is to be credited
to my ignorance of the close relationship existing between Ani-
sotrypa and Stenopora. This relation seems quite remote when
we compare only the typical species of the genera, but becomes
rapidly less distant with the extension of our comparisons, so
that now the only structures that are not common to the two
genera are the acanthopores. These are wanting in Anisotrypa
Another peculiarity that may hold good for the genus is the
ridge-like form of the interspaces separating the zocecia aper-
tures. The affinities with Rhombopora Meek, will be discussed
in my remarks upon that genus.

Six species are known to me at this time, the oldest being
from the Keokuk group in Lincoln county, Kentucky, and is des-
cribed as Rhombopora elegantula in my "Am. Pal. Bry.v It
agrees in all essential respects with A. symmetrica, and like that
species, has occasional large cells. Two species, the A. fistulosa

448 PALAEONTOLOGY OF ILLINOIS.

and ramulosa, belong to the St. Louis group. They are remark-
ably alike in tangential sections, but the first grows in irregu-
lar hollow branches, while the second forms small solid ramulets.
Two species differing from each other in precisely the same
manner, and from the St. Louis forms, by their much thicker
walls and somewhat smaller cells, occur in the Chester group.
The one I have called A. solida, the other must await an op-
portunity for publication. The sixth species is A. symmetries,
the type of the genus. It is not uncommon at several Chester
localities in Kentucky, and I have also seen specimens from Illi-
nois, that were collected by Mr. J. M. Nickles at Chester. A
good example is figured on PI. LXXII, fig. 5, to show the gen-
eral arrangement of the zocecia and the distribution of the
larger cells.

ANISOTEYPA FISTULOSA Ulrich.

PI. LXXII, fig. 6-6c.

Zoarium composed of from one to three layers, each about
one mm. in thickness, assuming the form of very irregular,
branching hollow stems, from less than five mm. to more than
ten in diameter. Inner side lined with a finely wrinkled epitheca.
Surface generally smooth, at intervals of three or four mm. with
clusters of apertures of larger size than the average, which
in rare instances are slightly elevated. A few small cells usually
present near the centers of the clusters. Apertures regularly
arranged, polygonal, commonly hexagonal, varying in diameter
from 0.28 mm. to 0.5 mm., in the clusters, nine or ten of the.
average size in three mm., separated by comparatively thin
partitions. Zooecial tubes curving gently throughout their
lenght, not quite direct even at the surface of the layers. Walls
thin and flexuous below, but towards the surface they become
rather abruptly, but only moderately thickened. Lines between
walls of adjoining zooecia sharply marked. Mesopores (?) (small
tubes) very rare, only in the groups of large zooecia. Diaphragms
with rather large perforations, three or four in each tube,
quite commonly observed closing their apertures.

This fine species is readily distinguished from A. symmetries,
(a Chester species) by the thinner walls and in having groups
of large cells instead of one or two zocecia of very large size.

BRYOZOA. 449

Position aiid locality: St. Louis group, Fella, Iowa. A simi-
lar species, having somewhat smaller cells, occurs in the Chester
limestone.

AMSOTRYPA RAMULOSA Ulrich.

PL LXXTI, flg. 7, 7o.

In its minute structure this species closely resembles A. fistu-
losa, from which it may be distinguished by its consisting of
small solid branches, from three to six mm. in thickness. The
cell apertures are about of the same size and shape, though,
perhaps always, separated by slightly thicker walls, and there
are clusters of large sized apertures. The minute structure of
the walls and the arrangement of the perforated diaphragms
in the mature region are not materially different. Vertical sec-
tions will of course be distinguished immediately by the solid
axis of the present species. The zooecial tubes in the axial re-
gion have very thin walls, and so far as observed are not
crossed by diaphragms.

Position and locality: St. Louis group. Pella, Iowa.

AMSOTRYPA SOLIDA Ulrich.

PL LXXH, flg. 9-9e.

Zoarium consisting of solid cylindrical stems, branching di-
chotomously and otherwise. The examples from Sloan's Valley,
Ky.. average three mm. in diameter, those from Chester, 111.,
nearly five mm. Surface with clusters of cells a little larger
than the average, which are only conspicuous when they are
slightly elevated. Zooecia polygonal, usually hexagonal, vary-
ing in width from 0.28 to 0.45 mm. in the clusters, nine or ten
of the average size in three mm. Apertures oval or subcircu-
lar, rarely angular. Zooecial tubes curving gradually from the
axial region to the surface where they are direct. Walls thin
in the axial, very much thickened in the narrow cortical region,
where they may present one or two faint constrictions. Adjoin-
ing- zcKHcia separated by a well marked divisional line. Inter-
spaces thick and ridge like. Three or more perforated dia-
phragms intersect the tubes in the mature region. Dark spots
—56

450 PALAEONTOLOGY OF ILLINOIS.

appear in tangential sections at the angles of the zooecia which
simulate acanthopores, but are not of that nature so far as I
can make out.

The solidity of the stems is the character that separates this
form readily from A. symmetries,, the type of the genus, figured
on PI. LXXII, fig. 5; it also lacks the single very large aper-
ture at the centre of the clusters, which is such a characteristic
feature of that species. The much thicker interspaces distin-
guish the species from A. ramulosa.

Position and locality: Chester group. Sloan's Valley, Pu-
laski Co., Ky., and Chester, 111.

AMPLEXOPORA. Ulrich, 1882.

("Am. Pal. Bry." Jour. Cin. Soc. Nat. Hist. Vol. V. p. 154.)
(For generic diagnosis see page 377.)

Fourteen species of this genus, ranging in time from the
Trenton to the Hamilton group, have been studied by me.
The two here described have thinner walls than is usual in the
genus, differing in that respect conspicuously from A. cingulata.
Still they present all the essential characters of Amplexopora,,
and are brought into closer connection with the typical species
than at first appears by such intermediate forms as A. superba
Foord, A. septosa and A. robusta Ulrich. In their general
structure species of Amplexopom resemble ramose species of
Stenopora Lonsdale, but are fundamentally distinguished by
the opercular structures, perforated diaphragms, and periodi-
cally constricted zocecial walls of that genus.

AMPLEXOPORA AFFINIS Ulrich.

PL XXXVI. fie. 2-2a.

Zoarium irregularly dendroidal, branching seldom, about fif-
teen mm. in thickness. Surface smooth, exhibiting scarcely ap-
preciable clusters of cells slightly larger than the average. Cell
apertures subpolygonal. Zooecial tubes polygonal, thin-walled,
seven or eight in two mm. Diaphragms somewhat more than a
tube diameter apart in the axial region, in the peripheral re-
gion about twice as close. A few infundibular diaphragms scat-
tered about promiscuously. Acanthopores conspicuous, usually

BRYOZOA. 451

situated between the zooecia, projecting more or less into one
or the other zooecial cavity, occasionally situated at the angles.

The affinities of this species are with A. septosa Ulrich, but
its thinner walls, less numerous acanthopores, and more robust
growth easily separate it from that form.

Position and locality: Cincinnati group. Wilmington, 111.

AMPLEXOPORA PVSTULOSA Ulrich.

PL XXXVI, fig. 3-3e.

Zoarium subrainose, lobate or irregularly compressed, of an
average thickness of eight mm. Surface rarely smooth, gener-
ally set with low monticules, about 2.6 mm. apart from center
to center, consisting of groups of larger cells with a few small
ones. Zooecial walls a little flexuous, thickened somewhat in the
cortical region. Zooecia polygonal, hexagonal and pentagonal,
about nine in two mm. Apertures subpolygonal, those in the
monticules one-half larger than the others. In the axial region
the diaphragms are about twice their diameter apart, but
become more numerous as the peripheral region is reached,
where they are somewhat less than a tube diameter apart.
Aeauthopores fairly numerous, commonly situated at the angles.
Usually there are two or three superposed mature regions with
diaphragms very crowded where the transition from one to the
next takes place.

This species differs in several important respects from A. sep-
tosfi Ulr. In that species acanthopores are more numerous and
project into the visceral cavity, tubercles are wanting or but
slightly elevated and the growth is strictly ramose.

Position and locality: Cincinnati group. Hanover. Clarks-
ville, and other localities in Ohio; probably occurs at Wilming-
ton, 111.

MONOTRYPELLA Ulrich, 1882.

("Amer. PaL Bry." Jour. Cin. Nat. Hist. Vol. V, p. 153.)
(For generic diagnosis see page 377.)

Species of this genus closely resemble Amplexopora and Homo-
trypa. but with a little practice it is not difficult to distinguish
between them. The absence of acanthopores separates them
from the first, and the absence of cystiphragms from the second.

452 PALEONTOLOGY OF ILLINOIS.

True mesopores are also wanting, but in several species, notably
M. crassimuralis and M. subquadrata, the zocecial walls are
partially separated near the surface by tabulated interspaces.

MONOTRYPELLA CKASSIMURALIS Ulrich.
PL XXXVIII, fig. 2, 2f.

Zoarium dendroid, dividing dichotomously or otherwise at in-
tervals from ten to eighteen mm.; branches with low rounded
monticules, whose centers are about two mm. apart. Zocecial
tubes after passing through the axial region with a steady
curve, open at the surface with direct circular apertures, 0.1
mm. in diameter, arranged in regular curved series, about eight
in two mm. Interspaces thick, flattened centrally, then sloping
down to the zooecial cavities; thickest on the monticules, where
a few illy defined mesopores are generall distinguishable. Tan-
gential sections vary considerably in the appearance of the in-
terspaces, sometimes showing open spaces of diverse form and
size between the ring-like walls of the zocecia, (see PI. XXXVIII,
fig. 2c); at other times the interspaces seem to be filled with a
light colored calcareous deposit. In transverse sections the
tubes in the axial portion of a branch are very thin walled and
regularly rhomboidal or pentagonal. Diaphragms wanting in
the axial, very few in the mature region; numerous and thick
in the interspaces.

This species belongs to the same section of the genus as M.
quadrata Kominger, and M. subquadrata Ulrich, though differ-
ing very obviously from them. All three agree in having the
tubes in the axial region regularly rhomboidal. Another pecu-
liar feature is the habit of changing the direction of the rhombs
at intervals of about one mm. This peculiarity is readily no-
ticed in rough vertical fractures, which exhibit concentric, alter-
nately smooth and rough or toothed spaces, each about one
mm. wide. In thin vertical sections each change is marked by
the origin of a number of rapidly enlarging young tubes.

The most striking feature of the species is the extreme thick-
ness of the interzooecial spaces. This character alone readily
distinguishes the species from its nearest allies.

Position and locality: Cincinnati group, Wilmington, 111.

BRYOZOA. 453

MONOTEYPELLA APPRESSA UMch.
PI. XLIV, fig. 1— Id.

Zoarium consisting generally of very much flattened branches,
occasionally sub-cylindrical. Surface smooth, with clusters of
cells larger than the ordinary size, little, if any, elevated, three
mm. apart measuring from center to center. Apertures of zooecia
thin-walled, polygonal, varying in diameter from 0.2 to 0.35
mm. In the axial region the walls of the zooecia are very thin,
but become thickened in the cortical region. In tangential
sections prepared since the plates were printed the median region
of the walls exhibit a minutely granular aspect. Zocecial tubes
curve but slightly and are still oblique in the peripheral region,
though the apertures appear to be direct; about seven of the
ordinary zooecia in the space of two mm. Three or four hori-
zontal or but slightly curved diaphragms are developed in the
transition period of the zocecial tubes.

M. pulchella Edwards and Haime, from the Wenlock limestone
of Dudley, England, has some affinities to this form, but has
much larger and more angular zocecia, with comparatively
thinner walls; the tabulation also differs. The species here des-
cribed approaches more nearly to M. sequalis Ulrich, from the
Cincinnati group of Ohio, the type species of the genus, but has
thicker walls, a much smaller number of diaphragms that are
also differently situated; and the zocecial tubes are oblique in
the peripheral region, while in M. sequalis they are direct.

Position and locality : Hamilton group; Rock Island, Illinois,
and Davenport, Iowa.

PETALOTRYPA Ulrich.

(For generic diagnosis see page 377.)

The bifoliate zoarial habit of this genus marks a decided and
easily recognized departure from Amplexopora, Monotrypella
and Leptotrypa, while in the zocecial features it is about equally
related to all of those types.

454 PALEONTOLOGY OF ILLINOIS.

PETALOTRYPA COMPRESSA Ulrich.

PI. XLVI, fig. 4-4f.

Zoarium consisting of compressed branches, two or more cm.
in height, one cm. or less in width, and form one to four mm.
in thickness. Surface smooth, with scarcely appreciable clusters
of cell apertures a very little larger than the average, and with
somewhat wider interspaces. Zooecial tubes almost direct from
the medial plane, the prostrate portion very short. Walls of
moderate thickness throughout. Zooecia sub-polygonal, at times
quite regularly hexagonal, about eight in two mm. The num-
ber of mesopores varies in different examples; disposed to con-
gregate in the clusters. Diaphragms abundant in the zooecia,
situated at rather unequal distances apart; in the mesopores
more closely set. Dark spots simulating acanthopores, or per-
haps really of that nature, found at some of the angles between
the zooecia. Between two adjoining zooecia there is a dark line
which is interrupted by tissue of the same color as the wall
substance. I am not prepared to give the exact interpretation
of this feature.

This species neither superficially nor internally can be con-
fused with any other species known to me from Devonian rocks.
Very frequently specimens are overgrown by a form of Aulopora
often causing the subsequent growth to be very irregular.

Position and locality: Hamilton group; Davenport, Iowa;
Rock Island, 111.

PETALOTRYPA DELICATA Ulrich.

PL XLVI, fig. 5-5a.

Zoarium a slightly undulated bilaminar frond, about two cm.
in height, the same in width, and 0.7 mm. in thickness. But
two examples of this species have been examined. Surface
smooth; cell apertures angular, subrhomdoidal or hexagonal,
arranged in diagonally intersecting series, about nine in the
space of two mm. measuring diagonally. Zooecial tubes very
short, approaching the surface in a steady curve. An occasional
diaphragm present at the beginning of the cortical region.
Acanthopores absent, though at some of the angles of the zooecia
are dark spots which may be of that nature.

BRYOZOA. 455

Its very much thinner zoarium, the rhombic cell apertures,
their regular arrangement and the almost total lack of dia-
phragms discriminate this form from P. compressa.

Position and locality: Hamilton group; Buffalo, Iowa and
Rock Island, 111.

LEPTOTRYPA Ulrich, 1883.

Am. Pal. Bry. Jour. Gin. Soc. Nat. Hist. vol. VI, p. 158.
(For generic diagnosis see page 377.)

My original diagnosis of this genus included only thin para-
sitic zoaria, but later investigation has shown that these could
not be separated from several species that differed only in the
thickness and ultimate form of the colony. The zocecial features
are identical in the massive and parasitic forms, nor is there
any difference in the general plan of construction.

Tho massive and discoid species present great resemblance to
MonotrypaNich., but good tangential sections serve to distinguish
the genera at once, acanthopores being a conspicuous feature in
sections of Leptotrypa, while such structures are wanting in
Monotrypa. In all about seventeen species of Leptotrypa are
known to me from American Palaeozoic rocks; of these one
(Chsetetes quadrnngularis Nich.) or perhaps two occur in the
Hamilton group, two in the Niagara, and the rest in the Cin-
cinnati and Trenton groups. The four species here described are
fair representatives of this genus.

LEPTOTRYPA HEXAGONALIS Ulrich.

PL XXXVI, Fig. 6-6a.

Zoarium forming parasitic expansions less than one mm. in
thickness, spread upon Orthoceras or Hyalithus. Surface smooth.
Clusters of cell apertures of almost twice the usual size are
arranged in diagonally intersecting rows; these clusters are about
three mm. apart, measuring from center to center. Zocecia
regularly hexagonal in shape, sometimes a little elongated,
seven measuring longitudinally, almost nine, diagonally, in two
mm., diameter of the smaller 0.2, of the larger 0.35 mm. Acan-
thopores prominent on the surface when well preserved.

456

The thin parasitic growth and markedly hexagonal cells are
the most noticeable features of this species.

Position and locality: Trenton group, Mineral Point, Wis.;
Calhoun Co., 111.; and Minneapolis, Minn.

LEPTOTEYPA FILIOSA D'Orbigny.

PL XXXVI, Fig. 7-7a.

Monticuliporafiliosa D'Orb., 1850. Prod, de Pal. t. I, p. 25.
Chcetetes ftliosa Ed. & H., 1851. Pol. Foss des Terr. Pal, p. 261.
Chcetetes filiosa ? Nich., 1875. Pal. Ohio. vol. II, p. 206.

This species is a very common one in the Cincinnati group at
Cincinnati, Ohio. It is massive in shape, sometimes attaining
a vertical thickness of thirty cm. or even more. The zooecial
tubes are regularly prismatic, seven or eight in two mm., with
groups of larger size. Diaphragms something over a tube
diameter apart, but become about twice as close-set as the
zooecial tubes near the top of a mature region. Acanthopores
few and inconspicuous, only present in the mature regions,
therefore only rarely met with in tangential sections. Mature
region very short. Many successive mature and immature
regions may be observed upon some specimens, the tubes usually
being continuous throughout the. zoarium. The sections figured
were taken from a small specimen from the Trenton group of
Calhoun Co., 111. This is the first time this species lias been re-
corded from so low a horizon.

LEPTOTEYPA STIDHAMI Ulrich.

PL XXXVI, Fig. 4-4b.

Zoarium irregularly lobate-massive. Surface smooth, with
clusters of somewhat larger cell apertures. Zooecial tubes radiat-
ing out in all directions from a point in the base, angular,
irregular in shape, and thin-walled even to the surface, from
eight to ten in two mm. Diaphragms horizontal, about a tube
diameter apart. Acanthopores ra.ther large, numerous, situated
at the angles of the zooecia.

The shape of the zoarium and the number and regularity of
the diaphragms, combined with the size and number of acantho-
pores, are the main distinguishing features of this species.

BRYOZOA. 457

The specific name is given in honor of Rev. I. F. Stidham, to
whose generosity I am indebted for the type specimens.
Position and locality: Cincinnati group, Brown Co., Ohio.

LEPTOTRYPA KEMIPILARIS Ulrich.

PI. XXXVI, Fig. 5-5d.

Zoarium small, massive, bat varying in shape from lenticular
to subglobose; usually hemispherical. Surface smooth or with
low broad elevations having a cluster of larger cells at their
apices. Zooecial tubes direct, thin-walled throughout, with sub-
polygonal apertures, about eight in two mm. Diaphragms
usually wanting, occasionally a few developed as the tubes
approach the surface. Acanthopores of moderate size and num-
ber, situated at the angles of the zocecia.

The greater regularity and slightly larger size of the zooecia,
the different shape of the zoarium, and the almost total absence
of diaphragms distinguish this species from L. stidhami, its
nearest congener.

Position and locality: Cincinnati group, Covington, Ky., about
300 feet above the bed of the Ohio river.

DIPLOTRYPA Nicholson, 1879.

(Pal. Tab. Corals, p. 292.)
(For generic diagnosis see page 378.)

In the general aspect and composition of the zoarium this
genus presents much resemblance to Prasopora Xich. and Ethr.
Juii. The absence of true cystiphragms, however, is an impor-
tant and easily recognized peculiar-it}-, that not only distin-
guishes the two genera, but also casts much doubt upon the
family relations of Diplotrypa. Such species as D. H hiteavsi Nich.,
and D. milleri Ulr., point to decided affinity with the CALLO-
PORiD-E. On the other hand D. regularis Foord, D. infida and D.
jjtitella Ulr., approach more nearly to Prasopora. In this
group of species the zooecial tubes are crossed by oblique, more
or less recurved, or occasionally even overlapping diaphragms.
In the last instance they simulate isolated cystiphragms in a
marked degree, but a careful examination has failed to show
that they are anything else than irregular or modified dia-
-57

458 PALEONTOLOGY OF ILLINOIS.

phragras, since in no case have I detected the unmistakable
appearance of cystiphragms in tangential sections.

D. petropolitana, the type of the genus and one or two simi-
lar but as yet undescribed species, seem to be very different
from the other species now classed under Diplotrypa. In fact I
regard them as more nearly related to Monotrypa and Baton-
toma, two genera constituting with the typical section of Diplo-
trypa the provisionally established family DIPLOTRYPID.E. The
ultimate position of these genera, however, depends largely
upon the results of future study and discoveries.

DlPLOTRYPA PATELLA Ull'ich.

PI. XXXIII, fig. 2-2c.

Zoarium lenticular; the typical specimen is twenty-five mm.
across, another larger example thirty-eight mm. across ; greatest
thickness, at centre, from two to four mm. Surface smooth,
thinly hirsute from the surface projections of the acanthopores,
showing clusters of cells larger than the average, but not ele-
vated above the general level. Under surface provided with a
thin and somewhat concentrically wrinkled epitheca. Zooecia very
thin walled, about eight in two mm. Apertures circular, some-
times polygonal, those of the normal size about 0.18 mm., the
larger 0.25 mm. in diameter, arranged in diagonally intersect-
ing series. Usually each zooDcium is touched by four others,
with an acanthopore situated at or very near the point of con-
tact. The interspaces between the zocecia are occupied by meso-
pores, bounded by three or four concave sides, Mesopores more
numerous in the clusters of larger cells. In the zooecial tubes
diaphragms are moderately abundant, straight, at times curved,
especially in the lower part of the tubes where they frequently
have the appearance of cystiphragms and may actually be of
that nature. In the mesopores the diaphragms are closely set,
about three in the space of a tube diameter.

The nearest congener of this form is possibly the D. regularis
Foord, from which it differs in having the mesopores larger, and
a much larger number of diaphragms in the tubes and other
less important features.

Position and locality: — Cincinnati group, Oxford, Ohio, and
other localities.

BRYOZOA. 459

DIPLOTRYPA? DUBIA Ulrich.

PI. XXXm, flg. 3-3b.

Zoarium discoidal. Upper surface with the usual style of cell
aperture ; lower surface with an epitheca. Zooecial walls slightly
wavy. Zooecia direct, circular, seven or eight in two mm.
Mesopores comparatively few, small, situated at the angles be-
tween the zocecia. Diaphragms horizontal in the zocecial tubes,
their diameter or more apart, closely set in the mesopores.
Acanthopores wanting.

As shown in fig. 3 a, the zocecial walls have a peculiar inter-
mittent structure, which seems conclusive evidence of the wTalls
having been originally minutely porous.

The small size and number of the mesopores make it some-
what doubtful whether this species is properly referred to
Diplotrvpa. This character and the absence of acanthopores
distinguish it from other described species of the genus.

Position and locality: — Cincinnati group, Wilmington, 111.

BATOSTOMA TJlrich, 1882.

("Amer. Pal. Bry." Jour. Cin. Soc. Nat. Hist., vol. V, p. 154.)
(For generic diagnosis see p. 379.)

Such species of the genus as B. implication Nich., and B.
jamesi Nich., are characterized by zooecia with thick ring-like
walls, irregularly oval apertures, numerous mesopores and
acanthopores. Although a closely allied species, B. variabile
Ulr., differs conspicuously from them in having few mesopores,
and polygonal zooecia. B. fertile Ulr., a species from the Tren-
ton shales of Minnesota, differs in the same way, but goes
farther in having acanthopores considerably reduced in size.
Two undescribed forms deviate from the typical species in very
much the same manner, and in one of them both the mesopores
and acanthopores are so much reduced in number that they are
practically wanting. Through these species the genus is made
to resemble Monotrypella and Amplexopora without, however,
there being any very intimate relationship. The true position
of the genus is between Diplotrypa and Monotrypa.

4(>0 PALAEONTOLOGY OF ILLINOIS.

A peculiar group of species comprises B. imperfectum Ulr., B.
irrasum Ulr., and B. ottawense Foord. These differ from the
other species in having incomplete diaphragms, and ought, per-
haps, to constitute a distinct genus.

BATOSTOMA VARIABILE Ulrich.

PI. XXXV, fig. 4-4e, 5, and PL XXXVI, fig. 1.

Zoarium exceedingly variable; encrusting, lobate, digitate,
ramose, and subfrondescent. Surface smooth, showing inappre-
ciably elevated clusters of larger cells. Walls of zooecia in axial
region thin, faintly and irregularly flexuous; much thickened in
the mature region; the tubes are polygonal, approach the surface
with a gradual curve, and are mainly in contact, with the divisional
line between those adjoining sharply marked. Apertures angu-
lar, averaging six in two mm. Mesopores angular, varying in
number, generally few as in the sections figured. Diaphragms
few in the immature region, three or four in the narrow cortical
region, the one or two nearest the surface concave; in the
mesopores they are moderately abundant. Acanthopores fairly
numerous, usually situated at the angles between the zocecia.

The name "variabile" is given to this species because different
examples exhibit considerable variations in the mode of growth,
in the number and arrangement of the mesopores, in the
amount of thickening of the walls in the cortical region, and
some other features.

This form bears much resemblance to the B. jainesi Nich.,
which, however, has oval zooecia separated by many mesopores,
while this species has the zooecia polygonal and often in contact,
with fewer mesopores and diaphragms.

Position and locality: — A very abundant and characteristic
species of the upper beds of the Cincinnati group. It is found
at numerous localities in Ohio and Indiana, and at Savannah,
111., and Delafield, Wis.

BATOSTOMA IMPERFECTUM Ulrich.

PI. XXXV. fig. 3-3d.

Zoarium ramose, branches subcylindrical, very robust, twenty
mm. or even more in thickness, dividing at short, irregular in-

BRYOZOA. 461

tervals. Surface marked with very slightly elevated aggrega-
tions of larger cells surrounding a larger or smaller cluster of
mesopores, about three mm. apart. Zooecial walls but little
thickened in the peripheral region. Mature portion of the
zooecial tubes usually longer than the immature portion; the
bend in the tubes is rather abrupt. Zooecia subpolygonal, about
seven in two mm., with subcircular apertures; the diameter of
the smaller apertures is about 0.2 mm., of the larger, constitut-
ing- the borders of the clusters, about 0.35 mm. A few meso-
pores scattered about irregularly among the zooecia, usually
gathered into clusters of from six to fifteen in the centre of a
group of the larger sized zooecia. Diaphragms present through-
out the zooecial tubes, some horizontal, some incomplete, vary-
ing in separation, in the axial region somewhat more than a
tube diameter distant, in the cortical region from one-third to
one-half of a tube diameter apart. Acanthopores (?)very small.

Sections of this form present some very interesting features.
In the axial region the diaphragms extend horizontally across
the tubes but in the mature region, they are incomplete and
crescentic in shape, rarely, if ever, extending more than half
way across the tube. In tangential sections another peculiarity
is brought out, namely, at the angles between the zooecial tubes,
there is a space, generally triangular in shape, of lighter color
than the remainder of the interspaces or wall. The points of
these spaces continue as dark lines that mark the divisional
line between the walls of adjoining zooecia. The walls exhibit a
horizontally lined appearance reminding one very much of the
wall structure observed in some of the CERAMOPORHXE (e. g.
Crepipora). In exceptionally good tangential sections minute
circles may be detected between the zooecial walls. They have
the appearance of minute thin-walled tubuli, and, though much
smaller than usual, are probably equivalent to the peculiar
acanthopores of this genus.

This species resembles B. ottawense Foord, in the possession
of incomplete diaphragms and the peculiar structure of the
walls, but differs in the closer arrangement of the tubercles, the
thinner walls, and inconspicuous acanthopores.

Position and locality: — Cincinnati group, Wilmington, 111.

462 PALEONTOLOGY OF ILLINOIS.

MONOTRYPA Nicholson, 1879.

(PaL Tab. Corals, p. 293.)
(For generic diagnosis see page 379.)

MONOTRYPA RECTIMTJRALIS Ulrich.

PI. XXXVIII, Fig. 4-4b.

Zoarium massive, varying from lenticular to sub-spherical in
shape, growing to be ten or more cm. in diameter. Surface
generally smooth, presenting, occasionally, faintly elevated
clusters of cell apertures, about one-half larger than the ordi-
nary size. Zooecia angular, direct, with exceedingly thin straight
walls; apertures polygonal, about six of the average size in the
space of two mm. Straight horizontal diaphragms from two to
four tube diameters apart. No acanthopores observed. There
are indications that the zoarium is built up of a number of
successive superposed mature regions with a very narrow imma-
ture region, separating two succeeding mature regions.

The simplicity of its structure is the most marked feature of
this species. It differs from M. undulata, Nich., and M. subglo-
bosa Ulrich, in having straight instead of undulating or crenu-
lated walls.

Position and locality: The type specimens are from the Cin-
cinnati group, in Alexander Co., 111. Examples apparently of
this species are quite common near Savannah, 111., and occur
more rarely at Cincinnati, Ohio.

CERAMOPORA Hall, 1852.

(Pal. N. Y. Vol. II, p. 168.)
(For generic diagnosis see page 380.)

The type species of this genus is so peculiar in certain re-
spects that I have deemed it advisable to figure its internal
structure. This is done on PI. XXXIX, by fig. 1-16. A brief
description of the species is as follows.

BRYOZOA. 463

CERAMOPORA IMBRICATA Hall.

f'erainopora imbricata Hall, 1852. Pal. N. Y. Vol. n, p. 169. PI. 40e, flg. la-li.

Zoarium free, discoidal. plano-convex, under side sometimes
slightly concave, from five to fifteen mm. in diameter; thickness
at center seldom exceeding four mm., usually only about two
or three mm. No epitheca on the lower side. Lower or basal
portion of zoarium composed of a cellular or spongy tissue,
from which the zocecia grow out more or less obliquely. At the
depressed center of the zoarium the zooecia are nearly direct,
but toward the margin they gradually become more and more
oblique. Zooecia compressed tubular, being long oval in trans-
verse section. Apertures imbricating, arranged in multiplying
radial series, all facing away from the center, triangular or
oval iu outline, 0.5 to 0.7 mm. in their long diameter. Inter-
cellular space occupied by irregularly flexuous rows of meso-
pores, variously shaped, short. Zooecial tubes and mesopores
communicate rather freely by means of perforations in the walls.
Besides the Avails have that granular structure which is sup-
posed to indicate an originally minutely porous condition.
Lunarhmi small, yet well marked. No diaphragms developed.

The remarkable features about this species are its free habit,
and the spongy basal layer. When compared with the other
forms which are generally referred to the genus, it does not
seem probable that they are congeneric. The Lower Silurian
species I refer to either Ceramporella or Crepipora. Several of
the Upper Silurian forms which Hall has regarded as congeneric
with C. imbricata, are most probably referable to the FISTULI-
PORID.E, (Eridopora Or.). The same is believed of Ceramopora
huronensis Nich., from the Hamilton formation.

Position and locality: Niagara group: Lockport, N. Y. (Hall);
Osgood, Indiana.

464 PALAEONTOLOGY OF ILLINOIS.

V

CERAMOPORELLA Ulrich, 1882.

("Amer. Pal. Bry." Jour. Cin. Soc. Nat. Hist. Vol. V, p. 156.*)
(For generic diagnosis see page 380.)

This genus is intended to receive a number of Silurian JBryo-
zoa that most palaeontologists would refer to Ceramopora Hall.
But, as I have shown, C. imbricata, the type of the genus,
differs too widely from these forms to admit of being referred
to the same genus.

Commencing in the upper half of the Trenton group with one
or two species, Ceramoporella is represented by six or seven
additional species in the Cincinnati group. Only three of these
are here described, while Nicholson's Ceramopora ohioensis is,
provisionally, also placed here. It is questionable whether the
genus is represented in Upper Silurian rocks. Some of the
species from that horizon, that have been described under Ce-
ramopora, present a close external resemblance to C. distincta,
yet I am inclined to believe that a careful examination of their
interiors will reveal Fistuliporoid characters.

CERAMOPORELLA DISTINCTA Ulrich.

PL XXXIX, flg. 6, 6a.

Zoarium forming thin, parasitic expansions upon Monticuli-
poroids or Orthocerata; by the formation of successive super-
imposed layers, large masses may result. The layers vary in
thickness from 0.5 to 1.0 mm. Surface even, though sometimes
appearing monticulose owing to the zoarium adapting itself to
the irregularities of the surface to which it is attached. Zooecia
thin-walled, at first prostrate, then becoming abruptly direct
or almost so, more or less triangular or pyriform, and with
well marked lunaria. In young examples very oblique, almost
imbricating. Apertures with thin obliquely projecting peristome,
more elevated posteriorly, oval in shape, about 0.2 mm, in

* A description of this genus was published as above cited in the synopsis of classi-
fication that appeared in the first part of my "American Palaeozoic Bryozoa." Unfortu-
nately, the publication of this memoir was discontinued ere I could take up the CEKAMO-
PORID.S:. As no good species of the genus was then described I could not name a type.
Hence the genus was not actually established, and ought, perhaps, to date from this
work.

BRYOZOA. 465

their longer diameter, arranged in regular series, about seven
or eight in three mm. Mesopores shallow, developed in great
numbers, usually arranged in a single or double linear series,
between the sides of the zocecia, occasionally completely isolat-
ing a zocpriuin. In the fully matured perfect condition their
apertures are closed by a thin membrane.

This very pretty species is distinguised by its small cells and
rather widely separated zooecia apertures. Their oval form and
the continuation of the peristome around the anterior margin
are also quite distinctive.

Position and locality: Cincinnati group. Abundant at Cin-
cinnati, Ohio, especially at the foot of the hills. The same
species, or a closely allied form, occurs at Wilmington, 111.

CKKAMOPORELLA STELLATA Ulrich.

PI. XLI, flg. 1. la.

Xoarium a thin subcireular crust upon foreign bodies. The
only specimen seen is 0.5 mm. in thickness, by about thirteen
mm. in diameter. Surface with prominent conical monticules,
their summits apparently solid, and about three mm. apart;
their sloping sides occupied by radially arranged zooecia. Zooe-
cia usually contiguous in the radial series, the series separated
by slightly concave furrows which diverge from the centre of
the monticules, and impart to the whole a stellate appearance.
Apertures very small, oval to subcircular, nearly direct, about
0.12 mm. in diameter, nine or ten in two mm. Hood or luna-
riuui very little developed except near the summits of the mon-
ticules. Mesopores very abundant, occupying the centers and
rays of the monticules, a few are found in the end spaces also.

The conical monticules and the decided radial arrangement of
the zocecia are such striking features, that I do not hesitate in
pronouncing this a very distinct species. It cannot be con-
founded with any other known to me.

Position and locality: Cincinnati group; Sterling, 111.
-58

466 PALAEONTOLOGY OF ILLINOIS.

CERAMOPORELLA GRANULOSA Ulrich.

PI. XLI, flg. 2, 2a.

Zoarium forming masses, consisting of many superimposed
layers, the initial layer being attached to some foreign body;
in the type specimen a species of Pachydictya. Surface even,
granulose with groups of larger cells. Zooecia oval, direct to
the surface. Lunarium prominent, narrow, occupying from one-
fourth to one-third the circumference of the wall. Apertures
somewhat oblique, irregularly oval, from 0.2 to 0.3 mm. in
diameter, in diagonally intersecting series, about six in two
mm. A considerable number of rather small irregular mesopores
are scattered about among the zooecia. Rather abundant thin
diaphragms intersect the tubes. A large number of small dark
spots, precisely like acanthopores in tangential sections occur
in the walls. Vertical sections, however, show that unlike these
structures they do not form continuous thick-walled tubuli, but
that they are developed at successive levels corresponding with
the diaphragms.

The granules, numerous diaphragms, and less regular arrange-
ment of its parts, distinguish this species from C. distincta
which it resembles in the size of the zooecia. I am not acquainted
with any other species that would admit of closer comparisons.

Position and locality: Cincinnati group; Wilmington, 111.

CERAMOPORELLA? OHIOENSIS Nicholson.

PI. XXXIX, flg. 2. 2a.
Ceramopora ohloensis Nich. 1875. Pal. Ohio, Vol. II, p. 265. PI. XXV, flg. 10,10e.

Zoarium incrusting, forming thin expansion over other Bryo-
zoa or the shells of Brachiopoda, 0.5 to 1.5 mm. thick, com-
posed, usually, of but a single layer, but sometimes of two or
three superposed layers. Surface with slightly elevated clusters
of zooecia of larger size and with thicker walls than usual. Zo-
cecia at first prostrate then rising abruptly, proceed almost
direct to the surface. Walls moderately thick. Apertures vary-
ing in shape, but more or less triangular or snbromboidal, and
oblique on account of the prominent elevation of the overarch-
ing lunarium or hood. Zooecia arranged in obscure radiating

BRYOZOA. 467

series around the elevated clusters, and in diagonally intersect-
ing lines on the spaces between them; here six or seven occur
in two mm. The long diameter of the apertures varies from
0.25 to 0.5 mm. in the clusters. A small number of irregular
mesopores, about one-fourth as large as the zooecia, are inter-
spersed among them.

At this time it seems highly improbable that this species is
congeneric with Ceramopora imbricata Hall. It is more nearly
related to Ceramoporella and Crepipora. and provisionally, I
propose to arrange the form as above. It is readily distin-
guished from typical species of the genus by its rather thick
walls and few mesopores.

Position and locality: Cincinnati group. Common at Cincin-
nati, Ohio.

DIAMESOPORA Hall, 1887.

Diamesopora Hall. Pal. N. Y. Vol. II, p. 158. 1852. (Not defined.)
Cwloclema Ulrich. Jour. Cin. She. Nat. Hist. Vol. V, 1882. (Not defined.)
Diamesopora Hall. Pal. N. Y. Vol. VI, p. XV, 1887.
(For generic diagnosis see page 380.)

This name stands for a convenient and easily recognized
genus of the CERAMOPORIDJE. Though already used in 1852, the
genus was not defined by Hall until 3887. There are no very
marked internal peculiarities, but the ramose form and the
hollow branches serve excellently to separate its species from
other Ceramoporoids. In these features they resemble Chilo-
trypn Ulr., but thin sections will immediately distinguish them,
as that genus is an unqualified member of the FISTULIPORID^E,
having vesicular tissue instead of untabulated mesopores.

The genus is represented by one undescribed species in the
Trenton limestone of Canada and New York, by D. vaupeli and
communis Ulrich, and D. oweni, (Fistulipora oweni James,) in
the Cincinnati group, by D. oscula, iufi-equens, sub-imbricata
dichotoma, tubulosa and varia of Hall* in the Niagara group,

* With the exception of D. dichotoma, all these species are described by Prof. Hall
as Trematopora. A closer examination of these Niagara forms will, I fear, prove that
they are not all distinguished by good specific characters.

468 PALAEONTOLOGY OF ILLINOIS.

and by 6'. constricts and venustfi (Trematopora constrict a
and venusta Hall,) in the Lower Helderberg group. Several
undescribed forms are known to me, and, so far as 1 am able
to judge from Billings' brief description, his Helopora circe and
H. variopora (Anticosti group) belong here.

DlAMESOPORA VAUPELI Ull'ich.
PI. XXXIX, fig. 3, 3b, and PI. XLI, fig. 4, 4c.

Zoarium consisting of hollow branches whose diameter varies
from two to five mm., the average being about three mm.;
thickness of zoarium a mm. or less. Surface even. Axial tube
circular, with nearly smooth epitheca. Apertures oval, about
0.18 mm. in their long diameter, arranged in very regular dia-
gonally intersecting rows, ten in three mm. measuring diagon-
ally, with prominent overarching hoods which are all directed
toward the distal extremity. Zocecial tubes at first prostrate
along the axial tube, then procumbent upon the next higher
zooecium, then bending abruptly to proceed more or less directly
to the surface. Mature portion of zoarium about twice as thick
as the immature. Zo(Bcial walls thin in the axial region, very
thick in the mature zone. Lunarium, at the lower or posterior
end of each zooecium, of lighter colored material than the rest
of the wall substance. Mesopores small, developed in consider-
abundance in the mature region. Diaphragms wanting.

This is a very neat and abundant species at the foot of the
hills about Cincinnati, O. In the absence of maculae and other
features it resembles some of the Upper Silurian species of the
genus, but more closely a small undescribed form occurring in
the Trenton limestone of Canada and New York.

The specific name is given as a small compliment to my friend
Mr. E. H. Vaupel, who was the first to point out its pecu-
liarities.

Position and locality: Cincinnati group, Cincinnati, O.

BRYOZOA. 469

DIAMESOPORA COMMUNIS Ulrich.

PI. XXXIX, Fig. Sa, and PL XLI. Fig. 5-5b.

This species is closely related to the preceding, but differs in
being more robust in growth, in having well marked maculae,
with subsolid centers, from which the cell apertures radiate out
in all directions. The apertures immediate surrounding the
maculae are also slightly larger than the others, while an ob-
scure concentric arrangement prevails. On the whole, the cell
apertures are also somewhat larger, and the peristomes thicker.

Position and locality: Cincinnati group.

This form is commonest in the layers exposed in the river
bank opposite Cincinnati, 0., where D. vaupeli is not known to
occur. It has a vertical range of about 125 feet, and in the
last 25 feet, the two species are found associated.

CREPIPORA Ulrich, 1882.

(Jour. Cin. Soc. Nat. Hist.. voL V, p. 157.)
(For generic diagnosis see page 380.)

This genus differs from Ceramoporella Ulrich, mainly, in the
nearly complete restriction of the mesopores to the maculae.
These usually form a conspicuous feature of the surface. The
lunarium is also better developed and the zooecia apertures
much less oblique than is usual in that genus. (7. impressa and
C. solida. however, are closely related to some of the aberrant
forms now classified with Ceramoporella.

Five representative species are here described, which, com-
bined, furnish a good idea of the limits of the genus. The sub-
ramose, hollow branched species, described by me as Chsetetes
venustus* although differing widely in its habit of growth, is
nevertheless closely allied to C. simulans. the type of the genus.
Beside these, my cabinet contains material of four or five un-
described species, all of them from the Cincinnati group. An
Upper Silurian species, closely related to C. epidermata, occurs
at Gotland. It is known to European palaeontologists as Dis-
copora squamata (Lonsdale sp.)

470 PALAEONTOLOGY OF ILLINOIS.

CREPIPORA SIMULANS Ulrich.

PL XXXIX, Fig. 4-4a, and PI. XL, Fig. 3-3a.

Zoarium encrusting, sometimes forming crusts of greater or
less thickness, at other times irregular masses by the develop-
ment of successive layers. Thickness of layers varying from one
to five mm. Surface exhibiting at intervals of three or four mm.
small clusters of mesopores, which are usually abruptly elevated
and surrounded by zooecia with larger orifices than ordinary.
Apertures arranged in more or less regular curving series, a
somewhat concentric arrangement about the maculae prevailing;
rhomboidal or subpolygonal in outline, 0.22 to 0.4 mm. in
diameter, the average being 0.25 mm.; about seven of those in
the intermacular spaces in two mm. Lunarium only observable
at the surface of the well preserved examples. Zooecial tubes
scarcely prostrate at their origin, then proceeding almost direct
to the surface; walls thin throughout. In sections the zooecia
are seen to be angular, sub-rhomboidal and in contact with one
another; the lunarium small, with the ends projecting a little
jnto the zooecial cavity and composed of much lighter tissue
than the rest of the wall. Mesopores developed only in the
mature portion of the zoarium, restricted to clusters in which
they number from ten to forty, thick walled, rather variable in
size and shape, oftenest oval. Among them the observer may
detect very small acanthopore-like structures. Diaphragms thin,
about a tube diameter or more apart.

This fine species is related to (J. venusta, Ulr., but that species
is essentially free and grows into irregular hollow branches.
The zooecial walls are also considerably thicker. In C. impressa
Ulr., the lunarium is much more pronounced, and the maculae
larger and depressed instead of elevated.

Position and locality: Not uncommon near the tops of the
hills about Cincinnati, 0. I have also collected the species at
Madison, Ind., and seen one specimen from Wilmington, 111.

"Jour. Gin. Soc. Nat. Hist., vol. 1. p. 93, 1878.

BRYOZOA. 471

CREPIPORA EPIDERMATA Ulrich.

PL XL, Fig. l-le.

Zoarium forming a subcircular undulating expansion, attain-
ing a diameter of eight cm. or more: the thickness varies from
two to eight mm. Upper surface with slightly elevated large
macula? of mesopores. varying both in size and arrangement;
usually about four or five mm. apart. Apertures directed out-
ward from the center of the zoarium, the lunarium being moder-
ately conspicuous, with no striking regularity of arrangement,
sub-circular to sub-triangular, 0.4 to 0.6 mm. in diameter:
about six in three mm. Zooecial tubes with walls rather thin
throughout, very soon after their origin proceeding almost
direct to the surface. Usually a single diaphragm is developed
in each tube. Lunarium occupying about one-third of the wall,
with a radial structure as shown in fig. le, pi. XL. Mesopores
abundant, variable in shape and size, scattered about among
the zocpcia, but mainly gathered into clusters of fifteen to fifty:
very irregular in vertical section, sometimes provided with a few
diaphragms.

The form of the zoarium, the structure of the lunarium, and
certain peculiarities of the mesopores, suggest affinities with the
FISTULIPORID.E. Specifically it is widely different from all the
other species of the genus excepting C. squamata (Discopora
xqnamata Lonsdale.) from the Upper Silurian rocks of England
and Gotland. The European form differs in several respects,
such as having the macula? smaller and the zooecia apertures
more oblique. The zoarium is also less robust.

Position and locality: Cincinnati group; common at Wilming-
ton, 111.

CREPIPORA IMPRESSA Ulrich.

PL XL, Fig. 2-2a.

This species, which has all the characters of the genus, is
chiefly distinguished by having exceptionally conspicuous lunaria,
and large sized, but irregularly distributed maculae, depressed below
the general level of the surface. The single specimen seen is
an elongated, hollow stem four cm. long by six mm. in aver-

472 PALAEONTOLOGY OF ILLINOIS.

age diameter. It evidently grew upon some cylindrical body
which has since been destroyed. Cell apertures direct, trans-
versely oval or sub-circular, with the teeth or ends of the
scarcely elevated lunarium projecting strongly into the visceral
cavity, generally arranged in a somewhat concentric manner
about the macula?. The apertures immediately surrounding the
maculae are a little larger than the rest; about eight of the
average size in three mm. A considerable number of mesopores
interspersed among the zocecia in addition to the clusters of
sixty to one hundred.
Position and locality: Cincinnati group; Covington, Ky.

CREPIPORA SOLIDA Ulrich.

PL XL, fig. 4-46.

Zoarium forming a thin crust attached to foreign bodies (in
the type specimens on Orthoceras); less than a mm. in thick-
ness. Surface studded with apparently solid small conical mon-
ticules about four mm. apart. Apertures rhombic or long oval,
frequently very irregular, especially near the monticules, with
strongly arching hood, making them appear more oblique when
the example is in a good state of preservation, than when some-
what weathered; about six in two mm. Maculae composed of
solid intertwining tissue and mesopores, having a somewhat
radial arrangement. A moderate number of mesopores inter-
spersed among the zooecia. Lunaria very pronounced in tan-
gential sections.

The conical, sub-solid monticules give this species a very
characteristic appearance, not possessed by any other known
to me.

Position and locality: Cincinnati group; in a small creek south
of Covington, Ky.

CREPIPORA HEMISPHERIC A Ulrich.

PI. XL, fig. 5-5b.

Zoarium hemispheric or discoidal, commonly about four cm.
in diameter and two cm. in height; base flattened or concave,
concentrically wrinkled. Upper surface even. Apertures direct,

BRYOZOA.

rhombic or subpolygonal, with no marked regularity of arrange-
ment, seven or eight in three mm. There are groups of slightly
larger cell apertures which are arranged about small and scarcely
perceptible macula*. Walls of zooecia thin and with a peculiar
ragged structure. Lunaria inconspicuous, easily overlooked.
Mesopores few, generally only two or three at the center of the
clusters. They are without the lunarium and have thicker walls
than the zotecia. Diaphragms thin and somewhat more than
their own diameter apart.

The external form, and the extreme paucity of the mesopores,
ilisting-uish this species from all the prescribed forms. It is more
closely approached by a large massive species that occurs rather
abundantly in a layer at the base of the Cincinnati group,
which is exposed near Harrodsburg, Ky.

Position and locality: Cincinnati group; not uncommon at
Wilmington, 111.

AXOLOTICHIA Clrich.

(For generic diagnosis see page 381.)

This genus is proposed for the reception of the following spe-
cies, and another that I have lately described from the Trenton
shales of Minnesota as Crepipora, impolita, (14th Ann. Rep. St.
Geol. Minn.). The tubulose structure of the lunarium is re-
garded as the principal distinctive character. The number of
these minute vertical tubes varies with the species, since in the
Minnesota form there are usually only three to each lunarium,
while in the Illinois species there are from five to seven.

AXOLOTICHIA POXDEKOSA Ulrich.

PL XTJ. fig. 3-Sd.

Zoariuin forming large, irregular, massive branches. Surface
smooth. Apertures approximately direct, irregularly sub-circu-
lar or oval, eight or nine in three mm. Their arrangement is
rather irregular, and there are no clusters of large ones. Lu-
narial hood inconspicuous, with minute pores in the perfect
Mate. Zooecial tubes thin-walled throughout, yet considerably

stronger near the surface than in the axial region, proceeding
— 59

474 PALAEONTOLOGY OF ILLINOIS.

from an imaginary axis to the surface with a gradual curve.
Diaphragms thin, about two tube diameters apart. Mesopores,
variable in shape and of moderate size, are numerously inter-
spersed among the zocecia. In thin sections the lunaria present
a very peculiar feature. Thus, when the tube is cut transversely
the lunarial or narrowest side is apparently composed of alter-
nating intervals of light and dark color. When viewed under a
high power the light intervals are seen to be of circular form,
and with the aid of vertical sections, we learn that they are
really of the nature of small vertical tubes. Two of the sides
must have been bounded by extremely thin walls, as they are
only very rarely preserved, the appearance ordinarily presented
in tangential sections being that of a simple perforation in the
zooecial wall. These small tubes, of which there are usually
about six in each lunarium, appear to have been crossed by
numerous diaphragms, usually about twice their diameter apart.

The massive ramose zoarium, and large zocecia, suffice to sep-
arate this species from all associated Bryozoa.

Position and locality: Cincinnati group; very abundant at
Wilmington, 111.

FISTULIPORA McCoy, 1849.

(Ann. and Mag. Nat. Hist. ser. 2, Vol. Ill, p. 131.)
(For generic diagnosis see page 382.)

It is only since December, 1885, that we know exactly what
form McCoy had before him when he proposed this genus. At
the date cited there appeared in the Ann. & Mag. of Nat. Hist,
a valuable treatise on the genus Fistulipora by Dr. H. A. Nich-
olson and Mr., A. H. Foord. The authors show that Dr. Nichol-
son's identification of McCoy's . F. minor* (upon which I had
based my estimate of the character of the genusf) was incorrect
the new name F. mucosa being applied to the species. It fur-
ther appears that McCoy's F. minor is identical with Phillip's

* Palaeozoic Tabulate Corals, 1879.

t Am. Pal. Bry. Jour. Cin. Soe. Nat. Hist. Vol. VII, p. 43, 1884.

BRYOZOA. 475

earlier Calamopora incrustans. Founded upon this species, Fis-
tulipora exactly occupies the ground that I had proposed to
assign to Lichenalia of Hall (loc. cit.} Unless it can be shown
that the original New York specimens, upon which Lichenalia
was founded, are different from the very abundant Niagara
species at Waldron, Ind., that is generally identified with L.
concentrica, Hall's name must be abandoned. Strictly then,
Fistulipora includes all the unilaminar forms in which the lunar-
iuni ("folds") is a recognizable feature. I am still in doubt
what course to pursue in disposing the large group of species
(at least fifteen) in which the lunarium is obsolete and the
zooecial apertures circular or oval. Fistulipora minor Nicholson
(non McCoy) seemed to belong to this group! and, relying
upon the correctness of Dr. Nicholson's identification, I pro-
posed in my Am. Pal. Bry. to restrict Fistulipora to species of
that tvpe. But, as already mentioned, F. incrustans, the type
of the genus, has distinct lunaria, and all the characters usually
assigded to Lichenalia, hence it is clear my proposal cannot be
entertained, and that FistuUpora as defined by me though
possibly congeneric, is not strictly identical with typical Fis-
tulipora.

Hall's new genus Thallostigma* is proposed for Bryozoa with
all the characters Fistulipora (Lichenalia) excepting that the
interzooecial spaces exhibit the cavities of the vesicles at the
surface. This feature is not of structural value and, in every
case that has come under my observation, it represented either
the young condition when the vesicles were forming, or the in-
terior of the vesicles was exposed by attrition.

The range of the genus as no Understood is very extensive, a
large massive form, not yet described, having lately been dis-
covered in the Galena limestone of Manitoba. Several Cincin-
nati group species which have been referred to the genus, prove
upon examination to belong to the CERAMOPORIDJ:, and, so far
as I now am informed, no true Fistulipora occurs in these

: Nicholson and Foord's figures of the species show faint "folds" in the walls which
were deither mentioned nor figured by Dr. Nicholson.

* Trans. A.lb. Inst. Vol. X, 1883. (Abstract published in 1881.) In Vol. VI, Pal. N. Y.
Prof. Hall abandons this name in favor of Fistulipora.

476 PALAEONTOLOGY OF ILLINOIS.

rocks. In the Upper Silurian rocks; however, the genus is re-
presented by at least ten species, in Devonian by from twenty
to thirty, in Lower Carboniferous by perhaps an equal number,
and terminates its existence in the Coal Measures, with five or
six species. The total number of valid species known to me
from American rocks alone is not less than seventy, while four-
teen species are recorded from European deposits.

FISTULIPORA COMMUNIS Ulrich.

PI. XL VII. fig. 1, la. PI. XL VIII, fig. 1, la.

Zoarium explanate, commonly attached to foreign bodies, at
other times free and provided with an epitheca, often composed
of layers, each a mm. or two in thickness. The surface is raised
into low, broad, rounded monticules two or three mm. wide,
and their summits three or four mm. apart. Apertures circular
with a very thin but distinctlv elevated peristome, generally
about 0.16 mm. in diameter, but attaining a diameter of 0.25
mm. near the summits of the monticules; distances apart rather
variable, those in the monticules more separated than the others.
In the intermediate spaces five or six occur in two mm. When
the surface is worn the apertures appear quite small and the
interspaces very wide. Zooecia thin walled, circular or oval,
provided with two or three distant diaphragms. Lunarium ob-
solete. Vesicles thin-walled, generally wide and shallow, about
two-thirds as wide as the zocecia, surrounding them in two or
more series and forming large clusters under the monticules.
In good tangential sections the vesicle spaces exhibit one or
more subcentral minute spots, which probable represent perfor-
ations in their covers.

This very abundant species was at first supposed to be the
F. minuta of Rominger, but from an examination of authentic
specimens of that species, it appears that his species is closely
allied to Liocleina occidens (H. & W. sp.) and not a Fistuli-
pora at all. The small zooecia, their circular form, and the
obsolete lunarium, distinguish F. communis from the associated
species.

Position and locality: Hamilton group. Buffalo, Iowa, and
Rock Island, 111.

BRYOZOA. 477

FlSTULIPORA MONTICULATA UMch.
PL XLVTL fig. 3— 3b. PI. XL VIII. fig. 2, 2a.

Zoarium consisting of more or less compressed hollow branches
one to three cm. in width and two and one-half to five mm. in
thickness; actual thickness of zoarium less than two mm. Sur-
face generally with broad rounded monticules of moderate ele-
vation, four or five mm. apart and arranged in diagonal rows.
Monticules composed chiefly of vesicles and hence have a sub-
solid appearance on the surface. Apertures with thick rounded
peristomes, more elevated on one side; somewhat irregular in
shape, commonly oval, 0.2 to 0.3 mm. in their greatest dia-
meter, about half their diameter apart. Zooecial walls only
moderately thin sometimes ring-like, the lunarium distinct, but
with the ends scarcely projecting into the zocecial cavity. Ves-
icles sub-angular, about two-thirds as large as the zooecia, sel-
dom in more than a single row between the zooecia, shallow,
often arranged in quite regular vertical series. Diaphragms
developed occasionally in the zocecial tubes. Vertical sections
indicate that upon the floor of each vesicle there was a cal-
careous deposit.

Typical examples like that represented by fig. 3, are readily
distinguished from other species of the genus. When without
monticules the species bears some resemblance to F. utricula
Rominger, but the absence of spines, which are a characteristic
feature of the surface of Rominger s species is sufficient to show
their distinctness.

Position and locality; Hamilton group, Buffalo, Iowa.

FlSTlLIPCRA ASTRICA UMch.
PI. XLVH, fig. 5— 5b. PI. XLVm, fig. 3.

Zoarium consisting of large, hollow, compressed branches, or
laminar expansions, several cm. wide, one and one-half to three
mm. thick. Surface marked with large, showy, depressed, star-
shaped macula1, at somewhat variable distances apart, averag-
ing six mm. measuring from center to center, forming rows of
greater or less regularity. Apertures sub-triangular or, more
commonly, pyriform, bidenticulate. with the lunarium pronii-

478 PALEONTOLOGY OF ILLINOIS.

nent, about six of the intermacular apertures in two mm. Zo-
cecia with thin walls and diaphragms about two diameters
apart. Vesicles rather large but irregular in shape and size,
rarely in more than a single series between the zocecia.

This fine species is distinguished from all Devonian species of
the genus by the larger and decidedly stellate maculae. These
lend the species considerable resemblance to F. asterhi Prout,
from the Keokuk group. In other respects, however they are
quite distinct.

Position and locality: Hamilton group, Buffalo, Iowa.

FlSTULIPORA COLLINA UMch.
PI. XL VII, Fig. fr-eb, and PL XL VIII, Fig. 5-5a.

Zoarium a circular expansion, five or more cm. in width and
one to three mm. in thickness; a wrinkled epitheca upon the
lower side. Surface with solid, more or less prominent, elon-
gated maculae or monticules, set in cross rows, their summits
about four mm. apart. Zooecial apertures arranged in some-
what concentric rows about the monticules, diminishing very
slightly in size as they recede from the monticules; sub-oval or
circular in shape, averaging 0.22 mm. but varying from 0. 1 7
to 0.27 in diameter, about one-half their diameter apart, about
eight in three mm. Apertures, so far as observed, Avithout a
distinct peristome, the lunarium too being generally obsolete,
but occasionally the apertures appear somewhat oblique on
account of a slight prominence of the posterior margin. In thin
sections the zocecial tubes are seen to contain a small number
of diaphragms, their walls being thin, the lunarium unrecog-
nizable, the vesicles comparatively small, of nearly uniform size,
but varying from one-third to two-thirds the size of the zooecia,
moderately shallow, angular, usually in only a single series be-
tween the zooezia, though a double row is commonly present
between those which open upon the slopes of the monticules.
All the walls have a minutely granular or intermittent appear-
ance.

In some respects this species resembles F. communis and F.
monticulata,, two common species at Buffalo, Iowa, which are
described in this work as new. The absence of a complete peris-
tome and smaller vesicles separate F. collinfi from both, while

BRYOZOA. 479

the larger zoc^cia help in distinguishing it from the former, and
the different habit of growth from the latter.

Position and locality: Hamilton group. Comparatively rare
at Buffalo, Iowa.

FISTDLIPORA FOORDI Ulrich.

PL XL VII, Fig. 7-7a, and PL XL VIII, Fig. 4-ia.

Zoaiium a broad expansion; when complete, probably eight
to ten cm. wide; the only example seen is two and one-half
mm. thick at the edges, and five mm. in the thickest part.
Under surface \vith an epitheca marked by rather faint irregu-
larly concentric wrinkles. Large solid macula?, nearly on a level
with the surface, occur at intervals of six to eight mm., measur-
ing from center to center. Apertures immediately surrounding
the maculae, larger and more prominent than the others, de-
creasing gradually in size toward the middle of the inter-macu-
lar spaces, from 0.2 to 0.4 mm. in diameter, arranged in regu-
lar intersecting series, sub-triangular or pyriform in shape.
Lunarium very prominent, usually giving the apertures a
decidedly oblique appearance. When the apertures are closed by
opercular covers, the zoarial surface seems studded with triangu-
lar points, a little more than the diameter of their base apart;
about ten in 5 mm. Interspaces in general slightly concave,
but exhibiting irregular, faintly convex spaces, which are most
distinct on the surface of the maculae. Zocecial tubes a little
oblique to the surface, with diaphragms somewhat more than
their own diameter apart. The two ends of the lunarium pro-
ject strongly into the broadly pyriform zooecia. Vesicles large,
angular, irregular in shape, forming but a single series between
the zocecia, less shallow (in vertical section) than usual; the
macula? are entirely made up of them. Tangential sections
show that the interspaces are really of less width than the
zocecia.

The present species is, perhaps, nearer related to F. astrica
Ulr., also from the Hamilton group, than to any other species
known to me. The points of dissimilarity between them are,
however, quite marked, and it is scarcely possible that they will
be confounded.

Position and locality: Hamilton group, Rockford, Iowa.

480 PALEONTOLOGY OF ILLINOIS.

FISTULIPORA SPINULIFERA Rominger.

PL XLVI, Fig. 3-3d.
Fistuhpora spinulifera Bominger, 1866. Proc. Acad. Nat. Sci. Phila., p. 121.

Zoarium ramose, branches one to three cm. in diameter. Sur-
face monticulose; the small, prominent, conical, and sub-solid
monticules about three mm. apart, and arranged in rows of
considerable regularity. Monticules composed of vesicular tissue
and, like the interzooecial spaces, minutely spinous when in a
good state of preservation. Apertures sub-oval, about 0.20 mm.
in their greatest width, and between six and seven in two mm.
Lunarium but little elevated, the ends sometimes prominent and
projecting slightly into the zocecial cavity. Zocecial tubes thin
walled, proceeding in a gradual curve to the surface upon which
they open almost perpendicularly. Diaphragms rather irregular
in position and distribution, none in the central part, few in the
outer portion of the axial region, numerous in the cortical re-
gion. Vesicles irregular, usually small, angular, very large in
the axial region, becoming gradually much shallower toward
the surface, surrounding the zocecia in one or two series. In
tangential sections the lunarium shows but faintly. These sec-
tions also show a large number of small spots, that resemble
thin-walled acanthopores. They do not appear to form con-
tinuous tubuli.

This form closely resembles monticulated specimens of an asso-
ciated species of Monotrypella, from which it should be dis-
criminated. An examination with the hand lens readily does
this. The ramose habit of growth, solid branches, and com-
paratively thin granulose interspaces, distinguish it from other
species of the genus.

Position and locality: Hamilton group, Alpena, Mich.

FlSTULIPOKA (?DlCHOTRYPA) CORRUGATA UMch.
PL XL VII, Fig. 8-8a, and PI. XL VIII, Fig. 6-6b.

Zoarium an irregular undulating or somewhat distorted ex-
pansion, one mm. or there about in thickness. Under surface
with a concentrically wrinkled epitheca, the wrinkles strong, sub-
equal, and closely approximated. Sharply denned, small solid
maculae, of stellate form, dot the celluliferous surface and are but

BRYOZOA. 48J

little if any raised above it. Measuring from center to center they
are about 2.5 mm. apart. The maculae are surrounded by com-
paratively large apertures, facing outward; having the hood or
lunarium very prominent. Apertures oblique, sub-triangular or
pyriform, bidenticulate, hooded, about 0.15 mm. in diameter,
rather closely approximated, an average of twelve or thirteen
in three mm. Zooecia at first oblique, then direct. The primi-
tive cells, as shown by deep tangential sections, are of elongate
semi-cordate form, and arranged between longitudinal lines.
Here they sometimes show a feature that reminds me of a su-
perior hemiseptum. Diaphragms apparently wanting. Vesicles
varying in shape, angular, approaching in size to the zocecia.
In the upper part of the zoarium the vesicles are filled up or
replaced by solid calcareous matter, exhibiting in good sections
a large number of minute dark spots.

The distinctive features of this neat and well marked species
are the small and closely approximated zocecia, the strong and
regular wrinkles of the epitheca, and the general resemblance of
the zocecial structure to that of the CYSTODICTYONID.E. Should
it prove that the form is bifoliate then it would have to be re-
garded as an unqualified species of Dichotrypa. In any event I
am strongly inclined to place it there.

Position and locality: Hamilton group, Thunder Bay, Mich.

FISTULIPOKA STELLIFERA Romiuger.

PI. XLVII. fig. 2. 2a.
Fistulijpora steilifera Rominger. 1866. Proc. Acad. Nat. Sci. Phila. p. 120.

Zoarium sometimes unilaminar, more commonly rising into
bifoliate expansions, from one to three mm. thick. Surface
nearly even, but sometimes the m acute are slightly elevated.
Maculae of stellate appearance, about four mm. from center to
center, the central portion and rays concave, smooth or finely
granular, appearing solid at the surface. Apertures oval or
circular, with prominent peristome, one side (lunarium) often
more elevated than the other. In perfect examples, the rim
bears from six to eight small blunt spines. The arrange-
ment of the zocecia apertures is quite regular, radial series being
the most marked around the maculae, where they are also
slightly larger and separated by wider interspaces than in the
—60

482 PALAEONTOLOGY OF ILLINOIS.

intermacular spaces. Here they are rather closely approxi-
mated, about six in two mm., with an average diameter of
0.18 mm.

In sections the lunarium is illy defined, the zooecia appearing
as regularly oval or circular. The interspaces are occupied by
a single series of rather large, angular vesicles, but in the im-
mediate vicinity of the maculae they often form double series.
In vertical sections the zooecial tubes bend abruptly outward
from the irregularly flexuous median laminae, and, a short dis-
tance above the bend are usually crossed by a diaphragm.
The vesicles decrease in height toward the surface, and near it
are largely filled by a secondary deposit of sclerenchyma.

The bifoliate zoarium suggests comparison with Meekopora,
Ulr., but I cannot find that the species approaches that genus
in any other respect. In its zooecial features it agrees closely
with the section of Fistulipora typified by F. communis Ulr.

The specimen here figured is identical with a number of exam-
ples collected at Rominger's original locality by Mr. J. M. Nick-
les. It also agrees quite closely with an authentic example of
the species, the principal difference noted being a slightly greater
elevation of the lunarium in the latter.

Position and locality: Hamilton group, near Alpena, Mich.,
where it was collected by Rev. W. H. Barris, who kindly pre-
sented it to the author.

MEEKOPORA Ulrich.

(For generic diagnosis see page 383.)

The two principal peculiarities of this genus, 7. e., the bifoli-
ate zoarium and the uniform direction of the zooecia apertures
toward the distal end of the zoarium, render it more than or-
dinarily easy of determination. In their general form and con-
struction the zoaria of Meekopora resemble those of Dichotrypa,
and the careless observer will probably confound them. A little
care, however, in comparing species of the t\vo genera will soon
bring to light several important differences, the genus under
consideration being an unequivocal member of the FISTULIPORIDJE,
while Dichotrypa is an equally true division of the CYSTODICTYO-
NID.E. A comparison of vertical sections brings to light some of

BRYOZOA. 483

the most striking differences (see PI. LXXYI, fig. 96, and PI.
LXXYII, fig. 7b). Thus the zocpcial tubes in Dichotrypa are re-
cumbent on the median lamina, then bending outward abruptly
proceed direct to the surface. A more or less developed superior
hemiseptum is usually recognizable, but diaphragms are absent.
On the other hand in Meekopora the tubes are gently curved
throughout their length from the median laminae to their aper-
tures withe ut becoming direct and, while hemisepta are wanting,
numerous diaphragms are present. Other important differences
might be pointed out, but as they will be obvious enough to
the student, the above are deemed sufficient for the present.

Four species are now referred to the genus, one of them pro-
visionally. Beside these my cabinet contains three more. All
the species now positively known to have the structure of the
genus are from Lower Carboniferous deposits.

MEEKOPORA EXIMIA Ulrich.

PL LXXVH, flg. 6-€d.

Zoarium a bifoliate, somewhat undulating, palmate expan-
sion, several cm. in width and two to five mm. in thickness.
Surface presenting large, slightly elevated, oval, smooth spots
or macuUp. arranged in somewhat regular diagonal rows, five
or six mm. apart. The apertures immediately surrounding the
macula^ a little larger than the others. Apertures in rather
regular oblique rows, all facing up toward the distal part of
the zoarium, sub-triangular or semicircular in outline, with
prominent overarching lunarial hoods; six or seven apertures
in three mm., each with a diameter of about 0.21. Ooecia few,
taking the place of one of the zooecia and consisting of a cyst-
oid elevation of the surface, with a small perforation at the
apex. . Zooecial tubes thin walled, extending with a gradual
curve to the surface, without, however, becoming direct. Lu-
narium usually obsolete in tangential sections, but sometimes
the ends project slightly into the visceral cavity. The axial
plane consists of two very thin closely adhering flexuous epi-
thecal membranes. Yesicles of irregular shape, much the larg-
est near the axial plane, often exhibiting an obscure concentric

484 PALEONTOLOGY OF ILLINOIS.

arrangement around the zooecia. As they approach the surface
the floor of the vesicles (the top of the underlying one) is cov-
ered with a deposit of light colored sclerenchyma, which ap-
pears to be traversed by minute vertical canals. Near the sur-
face this perforated deposit entirely fills the vesicles. It is of
darker color in the immediate vicinity of the zooecia. In tan-
gential sections showing the characters just beneath the surface
the zooecia are circular, the vesicles and lunaria unrecognizable,
at a deeper level the lunarium is fairly well shown, and the
form of the numerous vesicles, though they are still partially
filled with the deposit, is readily determinable. At the median
plane the zooecia are arranged between longitudinal lines. These
sections also show that the interspaces gradually increase in
width, w7hile the zooecia diameter decreases with growth. Dia-
phragms fairly numerous, flat or slightly concave, a tube diam-
eter or less distant from each other.

This fine species need not be confounded with any bryozoan
known to me from either the St. Louis or the Chester horizon.

Position and locality: Near the dividing line between the St.
Louis and Chester group, Monroe Co., 111. The species may be
found both above and below the line.

MEEKOPORA APPROXIMATA Ulrich.

PI. LXXVII, fig. 5.

Zoarium bifoliate, growing into irregularly undulating thin
expansions, from one to one and a half mm. • thick. Surface
smooth, with small solid maculae, their centers four to five mm.
apart. Apertures closely approximated, oblique, sub-circular or
subtriagular in outline, 0.20 to 0.30 mm. in diameter, arranged
in more or less regular diagonally intersecting rows, seven in
three mm. measuring along the rows; interspaces thin, the
lower margin of the aperture elevated into a prominent hood.
Median lamina? forming a rugosely wrinkled plane from wrhich
the zooecial tubes proceed with a gradual curve to the surface
which they reach obliquely. Diaphragms usually flat, most
abundant in the deeper portion of the zoarium, where also they
are often recurved. Lunaria quite angular in tangential sec-

BRYOZOA. 485

tions, but their ends rarely if ever project into the zooecial cav-
ity. The vesicles resting upon the median laminae are elongated
in the direction of growth, those resting upon them are smaller,
angular, comparatively few, and often failing to completely
isolate the zooecia.

This species is to be compared with M. eximia, but the thinner
zoarium, much more closely arranged zooecia and smaller maculae
distinguish the two species without much trouble. Thin sections
furnish additional differences. An undescribed associated species
is not so readily separated, though differing in several impor-
tant particulars. Its zoarium is two or three times as thick,
the zooecia separated by somewhat wider interspaces, and all
tlit- diaphragms strongly recurved.

Position and locality: Chester group. Chester, 111. Sloan's
Valley. Ky.

MEEKOPORA CLAUSA Ulrich.

PI. LXXVI, Rg. 6 and PI. LXXVH, fig. 7-7b.

Fistulipora? claitsa Ulrich, 1884. Jour. Cin. Soc. Nat. Hist. Vol. 7, p. 47.
PL 3, fig. 4, 4b.

This species of which a full description was given in the refer-
ence above cited, was there referred to Fistulipora with an (?)
added. The weighty points in which it differs from Fistulipora
then pointed to a generic separation which I was unwilling to
make without first finding similar species. This has been done
and the genus Meekopora established for their reception. M.
i-lnu^a is related to M. eximia, the type of the genus, but differs
too conspicuously in its habit of growth and other characters
to admit of confusing them.

Position and locality: Chester group. The types are from
Sloan's Valley and Grayson Co., Ky., but I have seen speci-
mens from Chester. Dl.

MEEKOPORA? APERTA Ulrich.

PL LXXVI, fig. 1, la.

Zoarium consisting of small compressed branches, several cm.
in height, about three to five mm. in width by one mm. in

486 PALEONTOLOGY OF ILLINOIS.

greatest thickness; cross section of branches lenticular; margin
acute, smooth or obscurely granular. Apertures subcircular or
oval, with a beveled margin, slightly flaring, from 0.20 to 0.25
mm. in diameter, arranged in diagonal curved rows, about four
in 2 mm. Interspaces slightly concave, rising around the aper-
tures to form a kind of peristome, which is more elevated below
than above, causing the apertures to appear slightly oblique
and directed toward the distal portion of the zoarium. Lunar-
ium indistinct. Axial membranes very thin and somewhat flex-
uous. Zooecial tubes for a short distance prostrate, then curv-
ing abruptly they proceed to the surface at nearly a right angle.
Diaphragms appear to be wanting. Vesicles angular with an
obscure longitudinal arrangement, those along the median lam-
inae very large, diminishing in size and increasing in numbers
with age. Near the surface they are replaced by or filled with
calcareous tissue.

The general appearance of this species is so much like that of
species of Cystodictya that I was at first inclined to refer it to
that genus. Upon a closer examination, however, I found that
the principal zooecial characters of the CYSTODICTYONHLE were
absent, and that in these features the species presented a marked
resemblance to Meekopora. Some care is required in distin-
guishing M. aperta from certain forms of Cystodictya pustulosa
Ulrich, and it will not surprise me should future investigations
prove these two species more closely related than is shown
by the material now at hand.

Position and locality: Keokuk group. Hare at King's Moun-
tain, Ky.

STROTOPORA Ulrich.

(For generic diagnosis see page 383.)

This genus is proposed to include a small group of Fistuli-
poroid species having a peculiar feature in common, which in
most cases is sufficiently obvious to render their separation
from other genera of the family a comparatively easy task.
The peculiarity referred to, in the ordinary state of preservation,
presents itself in the shape of large abruptly spreading cells,
having at the bottom an aperture of the average zofBcia size,

BRYOZOA. 487

and a thin irregular elevated margin. When perfect they ap-
pear as laterally perforated, prominent, round and smooth
tubercles, about 0.5 mm. in diameter. That they represent
ooecia will scarcely admit of doubt. The following three species
are all that are positively known to have this character, but
another form, of which my material is not good, most prob-
ably also belongs to the genus.

STROTOPORA PERMINUTA Ulrich.

PI. XL VII, fig. 4-4b.

Zoarium having the form of small, irregular, hollow branches,
with a rugosely wrinkled epitheca on the inside; thickness of
zoarium 0.5 mm. or a little more. Surface with subsolid,
slightly elevated, conical monticules, about two mm. apart from
center to center. Slopes of monticules occupied by zooecia facing
outward from the center, so as to form radiating series. Aper-
tures suboval, but generally a little irregular in shape, 0.10 to
0.12 mm. in diameter, and eleven or twelve in three mm. Lun-
arium very prominent and overarching. Interspaces once and
a half to twice the width of the apertures. Ooecia comparativelv
small, about 0.4 mm. in diameter, with an eccentric opening at
the bottom; when perfect with a dome shaped covering in which
there is a lateral opening. They vary somewhat in number, on
different fragments, being numerous on some and few on others.

The minuteness of the zooecia, the delicate zoarium, and the
dome-shaped oopcia, distinguish this species from all Fistuli-
poroid Bryozoa known to me from Devonian rocks. This spe-
cies is smaller in every respect than the Keokuk species next
described.

Position and locality: Middle Devonian. Falls of the Ohio.

STROTOPORA FOVEOLATA Ulrich.

PL LXXVII, Fig. 9-9a.

Zoarium having the form of solid compressed branches; four
or more cm. high, two or three cm. wide and four to eight mm.
thick. Surface with low, broad, rounded, generally transversely
elongated monticules. Inter-in onticular spaces less than the

488 PALEONTOLOGY OF ILLINOIS.

width of the monticules. Apertures irregularly arranged, the
interspaces being of variable width, those upon the monticules
more separated than the others; varying also in size and shape,
some being circular, others oval or sub-triangular. 0.29 to 0.30
mm. in diameter, and seven or eight in three mm. Lunarium
or hood moderately developed, occupying one side of the aper-
tures. Ocecia numerous, but without regularity of arrangement,
sometimes a number occur in close proximity to each other;
bowl-shaped, about three times as wide as the zooecia, with
prominent margins, circular or irregularly indented by the en-
croaching zooecia; in their perfect state, as shown by well pre-
served specimens, over-arched by a dome-shaped covering,
having a small round or crescentic opening upon one side.
Center of branch, in the specimens at hand, crushed out of
shape. Zooecia rectangular to surface in the latter part of their
course; provided with fairly numerous, thick, flat, or sometimes re-
curved diaphragms. Vesicles surrounding the zooecia in a single
or double series, uniform in depth, angular, variable in size and
shape, replaced near the surface by calcareous tissue, which is
perforated by numerous, small, longitudinal, irregularly arranged
tubuli, establishing communication between the surface and
vesicles. Lunarium composed of lighter colored tissue, occupy-
ing about one-third of the circumferance of the zocecium.

In the form and general aspect of the zoarium this species
resembles Fistulipora. compressa Rominger, a common species
of the Keokuk limestone. Indifferently preserved examples might
be confounded, but when in a good, or even in the ordinary
state of preservation, the ocecia of the one serve excellently in
discriminating between them.

Position and locality; Keokuk group, Bentonsport, Iowa,
and Warsaw, 111.

STROTOPORA DERMATA Ulrich.

»

PL LXXVII, Fig. 8-8a.

This species like S. foveolata, the type of the genus, consists
of compressed branches, but they are much less robust in every
respect, the thickness being seldom more than two mm. The
branches too seem always to have been hollow, with an epithe-

BRYOZOA. 489

cal lining on the inner side. The surface is more even, the cell
apertures are smaller, more rounded, the lunarium not so well
marked, the interspaces comparatively wider and slightly ele-
vated, so that they appear to slope down into the zooecial
apertures; of these about eight occur in three mm. The ooecia
are rather smaller, and the zocecial openings in the bottom,
eccentric in position. The ocecia, though also irregularly dis-
tributed, are less so than in S. foveolata. An arrangement in
transverse series is common. Interspaces minutely granular or
pitted.

Position and locality: Keokuk group, Keokuk, Iowa, and
Warsaw. 111. The specimens from Warsaw are a little more
robust than those from Keokuk. Not rare.

BUSKOPORA Ulrich, 188(5.

(Contr. Am. PaL voL 1, No. 1, p. 22.)
(For generic diagnosis see page 383.)

HrsKOPORA LUNATA Rominger.

PI. XLVn, Fig. 7-7d.

ii'itata Rominger. Proc. Acad. Nat. Sci. Phila., 1866.

ta HalL Trans. Albany Institute, voL X. abstract, p. 10, 1881.
L-ii-kopora dentata Ulrich, 1886. Contri. Am. Pal., vol. I. p. 22, PL n, fig. 5-5a.
Lichenalia, lunata Hall. Rept. St. Geol. for 1885. Expl. to pi. 31, fig. 1-9, 1887.
Lichenalia lunata Hall, Pal. N. Y.. vol. VI, p. 77, PL 31, flgs. 1-9, 1887.

A fine example lately obtained enables me to add some infor-
mation about this species. The example is evidently more
mature, its greatest thickness being about 4 mm., and shows
the fully developed characters at one point. Here the zooecia
apertures are much smaller than usual and the interspaces pro-
portionally wider. Upon close examination I find that this
peculiar appearance is due to a large portion of the original
aperature being covered by a thin membrane. The present ori-
fice occupies the space between the lunarium and the opposite
wall and is of oval or subcircular shape. The specimens being
silicified and entirely free from the matrix, it shows, where
fractured, the character of the interior. Fig. 7d represents a
portion of a vertical fracture and shows several zooecial tubes
—61

-490 PALEONTOLOGY OF ILLINOIS.

with the internal ridge and lunarium. Also the vesicles of the
interspaces. Diaphragms are few or absent in this example.
Hall says septa (diaphragms) are "frequent."

Position and locality: Middle Devonian, (Upper Helderberg?),
Falls of the Ohio.

BOTRYLLOPORA Nicholson, 1874.

(Can. Jour., vol. XIV, No 2.
(For generic diagnosis see page 384.)

BOTRYLLOPORA SOCIALIS Nicholson.

PI. XLin, Fig. 9-9b.

Botryllopora socialis Nich.,1874. Geol. Mag. n. s.,vol. I, p. 160, PL IX, fig. 16.
Botryllopora socialis Nich.,1874. Pal. Ont.. p. 96, fig. 32.
Botryllopora socialis Hall, 1884. Kept. State Geol. for 1883, p. 61.

Zoarium rarely solitary, generally consisting of a greater or
less aggregation of approximate or confluent disc-like colonies,
attached by their lower surface to foreign bodies; rugose corals
and Brachiopods seeming to be the most favored. Sometimes
specimens are found that are free, with a strongly wrinkled
epitheca below. These again may consist of several successions
of colonies growing one upon the other. Ordinarily, however,
there is but one layer of about one mm. in thickness. Diameter
of discs varying from two to four mm. Upper surface of disc
convex with a central cup-shaped or flattened depression, from
which radiate a number of depressed linear spaces, all of about
the same width, commonly bifurcating about half way out.
Between the depressed spaces are ridges that extend nearly to
the margin of the disk; about half way between the center and
the margin their number is usually doubled by the interpola-
tion of shorter ridges. Total number of ridges varying from
fifteen to twenty-five. Each ridge is occupied by two series of
zocecia, having rather thick adjoining walls, there being no in-
terspaces between them. Zooecia apertures circular or oval, less
than 0.10 mm. in diameter, about eight in one mm., (the
length of the long ridges) with horizontal or slightly concave
diaphragms, about three tube diameters apart. Central and

BRYOZOA. 491

radiating depressions occupied by angular sub-spherical or flat-
tened vesicles; about two or three times the diameter of the zooecia.
The space between the disks is taked up by much larger irregu-
lar vesicles, being several times as wide as those at the center
of the disks. These may represent ooecia.

Specimens from different localities vary a great deal in the
size of the disks and number of ra^-s. Possibly several species
have been thrown together, but without more material than is
now before me, it would be unwise to establish more species.
In the specimen figured the disks are larger than in any other
seen by me.

Position and locality: Hamilton group, Eighteen Mile Creek,
X. Y.; Arkona, Canada; Falls of the Ohio; Thunder Bay, Mich.
Probably also at Andalusia, 111.

CYSTODICTYA Ulrich, 1882.

(Jour. Cin. Soc. Nat. Hist. Vol. V, p. 152.)
(For generic diagnosis see page 385.)

This is one of the most important of the Palaeozoic genera
of Bryozoa, being abundantly represented by both species and
individuals, in the upper divisions of the age. No species are as
yet known from rocks of earlier date than Devonian, but in
the Upper Helderberg and Hamilton deposits the genus makes
its advent with a comparative!}' strong representation, no less
than twenty species having already been described that are
referable to the genus. Of these seventeen have lately been
published by Prof. Hall as species of Stictopora. Most of them
he illustrates, while the descriptions of the others are sufficiently
full to enable me to determine their generic relations. The fol-
lowing clearly belong to Cystodictya and not to Stictopora,*

* I find a foot note on p. 10 of a number of plates and explanations which are pub-
lished by Prof Hall in advance of his report as State Geologist for 1886. This note reads
as follows: "In relation to the genus Cystodictya, I may remark that every species of
Stictopora known to me possesses the characters on which the genus Cystodictya has
been founded." In answer to this decretory note, I wish to say, that Prof. Hall has
either entirely forgotten that his genus Stictopora was founded upon Lower Silurian
species of very different structure from Cystodictya, or he has failed to appreciate the
really essential characters of the typical species of his genus. He describes the genus
with six species in the PaL of New York, Vol. 1, published in 1847. On page 16 we find
Stictopora fpnestrata, page 17 .5'. glomerata, p. 50 5. labyrinthica, p. 51 S. ramosa, p. 74
the generic description and S.(?'> acnta, and on the page following S. elegantula. Now

492 PALEONTOLOGY OF ILLINOIS.

Stictopora crescens, invertis, linearis, ovatipora, perarcta, rigida,
semistriata, and vermicula, from the Upper Helderberg group;
and £ crenulata, incisurata, limata, ovata, i-ecta-linea, sinuosa,
subrigida, trilineata, and tumulosa, from the Hamilton group.
Regarding these Devonian species, I have to say at present only
that in my opinion Prof. Hall has drawn the specific lines un-
justifiably close, and that in some cases at any rate, he has
proposed two names where one would have sufficed. Of other
Devonian species, having the structure of fystodictya, S. gilberti
Meek, S. meeki Nicholson, and S. sukata Winchell should be
mentioned. In the Kinderhook and Burlington beds wo
meet with a small undescribed species having pustulose aper-
tures arranged longitudinally between low and broad ridges.
In the Keokuk limestone C. lineata Ulr., is common, while C.
pustulosa, C. americana, and C. nitida, three new species, are
more rare. C. ocellata is from a bed in Kentucky, doubtfully
referred to the Keokuk group. In the St. Louis limestone we
find in great abundance a variety of C. lineata, which might
be known as sancti-ludovici; also a wide form that I will pro-
visionally designate as var. major. In the Chester group the
genus is represented by one or two undescribed species, and in
the Coal Measures we find C. carbonaria Meek. The Waverly
deposits of Ohio also furnish several species.

whichever of these five species S. (?) acuta being unavailable), we may select for the type
of the genus, we never approach the ground occupied by Cystodictya. Stictopora as
now employed by me is based upon S. fenestrata. This species is congeneric with the
forms which I formerly proposed to call Rhinldictya, and is one of a number of dis-
tinctively Lower Silurian Bryozoa, differing from Eurydictya of the present work
almost solely in the form of the zoarium, which, insiead of broad indefinite expansions,
forms slender, parallel- sided bifurcating stipes. The student will do well to compare
figures on plate XXX with those of CYSTODICTYONID.S; on plates 76, 77 and 78. The 8.
fenestrata seems to me to be the most available of the six species originally referred
to the genus to stand as the type. S. glomerata, 8. ramosa and 8. labyrinthica are
too indefinite to have furnished the generic characters, while S.(?) acuta, although the
first to follow the generic description, cannot be utilized because Hall questioned his
reference of the species to the genus. 8. elegantula is the only other species having
any claim to the distinction. This species is one of a small but little understood group
of species, related to Sticlotrypa of this work, that most probably should be regarded
as generically distinct from the widely distributed group typified by /S. fenestruta and S.
nicholsoni, Ulr. In case 8. elegantula is made the type of the genus, then Bhinidiotya
will stand and Stictopora have only two or possibly three representatives. In no case,
however, can Stictopora be made to include Cystodictya.

BRYOZOA. 493

CYSTODICTYA HAMILTONENSIS Ulrich.

PI. XLII, flg. 4. and PI. XLHI, flg. 1.

Zoarium a bifurcating stipe, from 2.5 to 3 mm. in width be-
tween the bifurcations, and 0.5 mm. in greatest thickness. Bi-
furcations frequent, commonly at intervals of about 8 or 9
mm. After bifurcation the two divisions bend a little toward
each other. Non-poriferous margin narrow. Cell apertures in
parallel longitudinal rows between strong elevated ridges; eight
or ten rows just before bifurcation, half going into each divi-
sion, soon after bifurcation the number of rows reaches by in-
terpolation the normal number seven or eight. Those in ad-
joining rows alternate with each other, causing an arrangement
in intersecting series extending diagonally across the branch.
Apertures almost circular or oval, about 0.2 mm. in diameter
and six in three mm. measuring lengthwise, those in the margi-
nal rows a little larger than the central ones, with a slightly
elevated peristome, a little stronger at the outer side, causing the
apertures to appear a little oblique. Lunariurn strong only in
old examples, usually quite inconspicuous. End spaces equal to
about one and a half times the diameter of the cell apertures.
Internal structure in accord with generic requirements.

This seems to be a characteristic species of the western ex-
posures of the Hamilton group, if not also of the eastern. It
is closely allied to C. sukata (Stictopora sulcata Winchell) but
differs in the disposition of its parts.

Position and locality: Hamilton group. Buffalo, Iowa and
Rock Island, 111. The same or a very similar form occurs at
Eighteen Mile creek in N. Y., and near Milwaukee, Wis., on the
lake shore.

CYSTODICTYA NITIDA Ulrich.

PL LXXVI, flg. 4— Ic.

Zoarium a narrow stipe, about 1.5 to 2 mm. in width, branch-
ing dichotomously at intervals of from 8 to 12 mm. Non-po-
riferous margin very narrow. Apertures in linear series, between
scarcely elevated ridges, five to eight of these series upon each

494 PALEONTOLOGY OF ILLINOIS.

face of the zoarium. In the matured perfect state (fig. 4b) the
apertures are circular, small, less than 0.1 mm. in diameter, raised
above the ridges with prominent projecting peristome. Aper-
tures also arranged in rather irregular diagonally intersecting
series across the branch. Summits of the ridges with delicate
flexuous lines, the whole of the remaing interspaces finely gran-
ulose. In the less mature state (fig. 4c) the apertures are much
larger and bounded on two sides by crescentic margins, the
outer one (lunarial) promptly elevated, directed slightly toward
the center of the stipe and curved to a shorter radius than the
opposite. Measured lengthwise six aperturs occur in three mm.
obliquely about three in one mm.

This species is much smaller than the C. lineata Ulr. It is
more closely related to C. americana Ulr., which see for com-
parisons.

Position and locality: Keokuk group. Bentonsport, Iowa.

CYSTODICTYA AMERICANA Ulrich.

PI. LXXVI, flg. 5, 5a.

Zoarium a long narrow stipe, not observed to branch, about
1.5 mm. in width. Transverse section of branches sub-acutely
elliptical, with the two sides more convex than usual. Each
side with four or five linear series of apertures, arranged between
prominent rounded ridges at the bottom of moderately deep
sulci, 5 or 5% in three mm. Apertures much elevated, small,
circular, and about 0.08 mm in diameter in the perfect mature
stage; in the ordinary condition much larger, subelliptical, 0.18
mm. in length by 0.13 mm. in width, and with the margin
most elevated on the outer side. The cells are also quite regu-
larly arranged in diagonally intersecting series. End spaces from
two to four times as long as the diameter of the cell apertures.

This species I formerly considered identical with C. parallels
Phillips (species) from the Carboniferous shales of Great Britain.
Comparisons lately made have shown that the English species
has both external and internal peculiarities not possessed by
its American representative. It is closely related to C. nitida
Ulr., but that species has the stipe frequently bifurcated, the
zooecia a little more numerous, and their arrangement in dia-

BRYOZOA. 495

gonal lines less regular. The longitudinal ridges are stronger,
the rows of cells generally less, and the surface more convex in

"weiicaua.

Position and locality: Keokuk group; King's Mountain Tun-
nel, Ky.. and Bentonsport, Iowa.

CYSTODICTYA PUSTULOSA Ulrich.

PI. LXXYI, fig. 2, 2a.

This species differs from C. lineata ("Am. Pal. Bry." Jour.
Cin. Soc. Xat. Hist. Vol. VII, p. 37, PI. II, fig. 4, 4c) mainly
in the fact that the hues which form so conspicuous a feature
on C. lineata are obsolete or almost wanting, and that the
apertures occupy the summits of prominent papilke. imparting
to the surface a strongly pustulose appearance, quite different
from what we find in C. lineata. A tangential section dividing
the zooecia just above their decumbent portion shows a very
peculiar feature, which I am not yet able to explain. Namelv,
the zocpcial cavity is here divided longitudinally by a line which
commencing at the posterior side of the subcircular wall, ex-
tends about three-fourths of the diameter to the opposite side.
A similar but shorter line has also been observed in a section
of C. lineata. These sections also show that the zooecial cavity
is larger in C. pustulosa than in C. lineata.

Position and locality: Keokuk group; King's Mt. Tunnel, Ky.;
Keokuk, Iowa: Warsaw and Xauvoo. 111.

CYSTODICTYA LIXEATA var. MAJOR Ulrich.

PI. LXXYI, fis. 3.

Comparison of sections of this form with those of typical
specimens of C. lineata has not developed any appreciable dif-
ference in internal structure. Externally this variety is more
robust and has three or four more rows of cells than the typi-
cal form. All the examples seen are badly preserved. Better
material may show differences which are not now obvious.

496 PALAEONTOLOGY OF ILLINOIS.

Po&ition and locality: The specimens are attached to the sur-
face of a slab of rock labelled only "Keokuk limestone.'' This
is probably an error as the character of the rock is decidedly
like that of the St. Louis limestone at Alton, 111.

COSCINIUM Keyserling, 1846.

(Eeise in das Petschora Land, p. 191.)
(For generic diagnosis see page 385.)

So far as I am aware the minute characters of the type of
this genus have never been made public, so that there is yet a
possibility of error when we refer species here. The probabili-
ties, however, are decidedly against C. cyclops Keys., being
generically distinct from such species as C. cribriforme Prout,
and C. latum, of the present work. These two species belong to
a small group that is first met with in the Upper Helderberg,
and extends up into the Coal Measures. The form of the
zoarium is precisely like that of Chithropora Hall, and authors
have usually regarded that genus as synonymous with Cosci-
nium. This is an error if my understanding of C. cyclops is
correct, since Hall's genus is closely related to Ptilodictya Lons-
dale, while Coscinium, as defined by me, is an unquestionable
member of the CYSTODICTYONID^E. In 1859, Prout identified a
species from the Falls of the Ohio with the C. cyclops, and at
the same time described a new species from the same locality as
C. cribriforme. In my "American Palaeozoic Bryozoa," I also
described and figured a species as C. cyclops. During the pro-
gress of this work I have made it a duty to reconsider every
previously determined point. In this case the result was more
than usually gratifying, since I can now rectify several errors.
I learn that the C. cyclops of Prout, is the Clathropora inter-
texta Nich., (a true species of that genus) and not the same as
Keyserling's species; that my C. cyclops and Hall's Clathropora
carinata (later Coscinotrypa carinata) are the same as Coscinium
cribriforme Prout. With regard to the true C. cyclops, I shall
hold that it is not known in the rocks of this country. In rela-
tion to the generic characters of this species I have only this
to say, that every zooecial feature mentioned by Keyserling

BRYOZOA. 497

(among which I find the lunarium) agrees well with what is
found in C. latuw, PI. XLIII, fig. 8, shows the perfect zooecia
apertures in C. ci-ibri forme.

COSCENIUM LATUM Ulrich.

PI. LXXYI, Fig. 7-7b.

Zoariuni growing from, an expanded base, attached to foreign
bodies, into a flabellate, reticulated frond, from 5 to 10 or
more cm. in height and width; consisting of regularly inosculat-
ing flattened branches, about one mm. thick and four or five
mm. wide. Fenestrules broad oval, 3 or 4 mm. long and 2 to
3 wide, arranged in rather regular intersecting series. Margins
of fenestrules and basal portion of zoarium noii-celluliferous and
very finely granular. Zooecia apertures arranged in regular,
curved, diagonally intersecting series, and in less regular trans-
verse and longitudinal rows. When the specimens are worn the
last arrangement is the most obvious; seven to nine rows be-
tween the fenestrules. Apertures when well preserved, with
unequally elevated peristome, commonly kidney shaped or sub-
pyriform, more rarely, sub-circular, a little larger near the
feuestrules than over the central portion of the inosculating
branches, varying from 0.15 to 0.25 mm. in diameter on an
example in the ordinary state of preservation, six or seven in
three mm. measuring diagonally, more than their own diameter
apart. Lunarium generally evident, always directed away from
the nearest fenestrules. Interspaces solid at the surface, flexu-
ously striated or finely granular; internally occupied by vesicu-
lar tissue.

This fine species is the only one known to me from the Lowrer
Carboniferous rocks. It differs from the Devonian C. cribiforme
Prout, it its wider branches and interspaces, the elevated zooecia
apertures, and in their obvious diagonal arrangement.

Position and locality: Burlington limestone: Calhoun Co., 111.,
Quiucy, 111., and Burlington, Iowa.

—(32

498 PALAEONTOLOGY OF ILLINOIS.

DICHOTRYPA Ulrich.

(For generic diagnosis see page 386.)

Only one previously described species, the Fistulipora, flabel-
luw, of Rominger, seems to have the characters ascribed to this
genus, yet I do not doubt that when the Palaeozoic Bryozoa
are more fully worked out, the genus will occupy a prominent
place in our classification. Already I can determine seven well
marked species, beside fragments of one or two other species
from the Keokuk group. The seven described here belong, one
to the Niagara, one to the Hamilton, and five to the St. Louis
group. The great prominence of the genus in the last forma-
tion is a rather peculiar circumstance, since remains of Bryozoa
are comparatively rare in these beds.

DICHOTRYPA GRANDIS Ulrich.

PI. XLII, Fig. 1-le.

Zoarium a large undulating frond, attaining a height of 13
cm. or more, a width of more than 7 cm., and at hickness of 4
or 5 mm. Surface smooth, but exhibiting, generally, small and
inconspicuous solid maculae. Apertures arranged in bent
diagonal series, about seven in three mm. measuring longitudi-
nally or diagonally, with a total absence of ridges, the inter-
spaces being flat. Orifices sub-oval, about 0.15 mm. in diame-
ter, with slightly elevated peristome. Interspaces from one and
a half to twice the diameter of the apertures. Zotecia at first
thin-walled, prostrate, commonly of obovate form; with the
vestibule tubular and traversing the space to the surface at a
right angle with same. Interspaces filled with vesicles, which at
first decrease in size outward, and, long before the surface is
reached, become filled with solid tissue. Lunarium occupying
from one-third to one-half the circumference of the zo<Bcial
boundary, not very conspicuous, but usually with one end pro-
jecting tooth-like into the cavity.

This is the strongest as well as the earliest species of the
genus known. In its minute structure it seems to compare more

BRYOZOA. 499

favorably with species from the St. Louis limestone than with
the Devonian form next described.

Position and locality: Niagara group; Will Co., 111., near
Wilmington.

DlCHOTRYPA FOLIATA, UMch.
PI. XLII, Fig. 2-2g.

Zoarium palmate, or an explanate undulating frond. Entire
dimensions unknown but attaining a height and width of six or
eight cm.; thickness two mm. or less. Surface even, but marked
with slightly depressed, circular or elongate, solid maculae,
arranged in more or less regular series, three or four mm. apart
measuring lengthwise. Apertures arranged in linear series between
longitudinal ridges. These ridges are most prominent in worn
specimens; when the surface is well preserved they scarcely show
and in this case the arrangement of the cells in diagonally in-
tersecting series, due to their alternation in adjoining rows, is
most conspicuous. Apertures circular, 0.12 to 0.15 mm. in
diameter, their own diameter or somewhat more apart, about
eight in three mm., measuring either longitudinally or diago-
nally. Peristome a little more elevated on one side than on the
other. Primitive zooecia prostrate, of semi-cordate form, with
the vestibule tubular and almost rectangular to the surface.
Walls of vestibular portion of zooecia ring-like, traversed at the
posterior side by a small vertical pore. Lunarium very faint'
Interspaces filled in the deeper parts of the zoarium with small
vesiculse; as the surface is approached these give way to solid
tissue. Superior hemiseptum, when preserved, strong and pro-
jecting well into the zooecial cavity.

This beautiful bryozoan cannot be confounded with any other
form known to me from the Hamilton group. The longitudinal
arrangement of the zooecia apertures distinguishes it from other
species of the genus.

Position and locality: Hamilton group, Buffalo, Iowa.

500 PALEONTOLOGY OF ILLINOIS.

DlCHOTRYPA ELEGANS UMch.
PI. LXXVI, fig. 8-8d.

Zoarium a more or less undulating frond, or palmate expan-
sion, several cm. in width and heighth, 1.5 to 3 mm. in thick-
ness; with the lateral margins sub-acute and non-poriferous.
Lower portion of zoarium perfectly smooth, being covered by
a dense cortical substance. Above this the surface is marked
with circular or sub-stellate solid maculae, which sometimes
crown the summit of low, broad, rounded monticules. Maculae
more or less regularly arranged, about three mm. apart; with
the apertures immediately surrounding them, slightly larger
than the others: Apertures a little oblique, circular, from 0.11
to 0.16 mm. in diameter, with elevated peristome, usually high-
est on one side, arranged in regular bent diagonally intersecting
series, about once and a half their diameter apart, eight of those
in the intermacular spaces in three mm. Interspaces sometimes
slightly concave, generally with a faint ridge or ridges, forming
sub-polygonal depressed areas around the zocecia apertures. In-
ternal structure similar to that of the type of the genus, but
the primitive portion of the zooecia is not regular in its form.
Just below the surface the inter-zooecial spaces are more dis-
tinctly marked with the intermittent concentric lines.

This species differs from D. intermedia and D. expatiata, by
the smooth lower portion of the zoarium, the sub-stellate mac-
ulae, and the less strongly developed lunarium. From D. flabel-
lum, Rominger, and D. lyroides, by its different growth.

Position and locality: St. Louis group; Elizabethtown, Ky.;
Jersey and Monroe Co.'s, 111.

DlCHOTRYPA INTERMEDIA Ulrich.

PI. LXXVI, fig. 9-9c.

Zoarium sub-ramose, consisting of an explanate frond
which throws off at intervals similar fronds, till there is pro-
duced somewhat the appearance of several successive fans grow-
ing from one another; entire height eight or more cm., width
varying from one to three cm.; thickness rarely exceeding 1.5

BRYOZOA. 501

mm. Margin sharp, with a wide non-poriferous border. Sur-
face smooth, with inconspicuous solid maculae on a level with
or slightly depressed below the general surface, at variable dis-
tances apart. Apertures sub-pjriform to sub-circular, 0.12 to
0.15 mm. in diameter, with uneqally elevated peristome, about
one and one-half or two times their diameter apart, arranged
in diagonally intersecting series, seven or eight in three mm.
Internal structure like that of the preceding species, but the
vesicles are very crowded vertically and smaller in tangential
sections. The solid tissue near the surface is lined longitudin-
ally rather than concentrically. Lunaria pronounced, constitut-
ing a conspicuous feature in tangential sections.

This species in its subramose zoarium and better developed
hmariuni approaches Cystodictya. The propriety of referring
the species to Diehotrypa rather than to Cystodictya, scarcely
admits of question.

Position and locality: St. Louis group; Alton, 111.; St. Louis,
Mo.

DlCHOTRYPA EXPATIATA.
Not figured.

So far as observed, this species closely resembles D. intermedia
in nearly all its minute characters, but differs so strikingly in
the form of the zoarium, that I am inclined to believe that bet-
ter material than is now at hand, will show corresponding zooe-
cial differences. The zoaria before me have grown into large
thin undulating expansions, one of them (incomplete) being
about 15.5 cm. long by 11 cm. wide: its thickness varies from
0.7 to 2.0 mm.

Whether specifically distinct from D. intermedia or not, the
two forms are easily distinguished, and I have, therefore,
thought it desirable that they be known by separate names.

Position and locality: St. Louis group; Alton, 111.

DICHOTRYPA FLABELLUM Romiuger.

PI. LXXVII, fig. 1-lb.
Upora flalteUnm Rominger, 1866. Proc. Acad. Nat. Sci.Phila. p. 122.

Zoarium having a strong, expanded base, roughly marked on
the lower side with a concentrically wrinkled epitheca. On the

502 PALEONTOLOGY OF ILLINOIS.

upper side the base gradually contracts into a flattened or sub-
cylindrical stem which soon expands again into a bifoliate, fan-
shaped frond, from 1.5 to 4.0 mm. in thickness, and several
cm. in width and height. The base, stem, and lower portion of
large examples is covered with a faintly striated dermatic crust.
Above this the surface presents solid sub-stellate maculae, four
or five mm. apart, bordered by apertures very slightly larger
than the rest. In the perfect state the apertures are oval, 0.12
to 0.15 mm. in length, with the lunarium on one side more or
less elevated. In the ordinary state of preservation they ap-
pear much larger (about 0.2 mm.) and the interspaces corres-
pondingly narrower. The apertures are regularly arranged in
intersecting lines, sometimes with six, but more commonly with
seven in three mm. Interspaces generally a little elevated, and,
when well preserved, covered with fine flexuous striae. These
also occur on the surface of the maculae.

The flabellate zoarium of this species is such a constant char-
acter that it suffices to distinguish it from all others. Wei
preserved fragments may be recognized by the striate inter-
spaces.

Position and locality: St. Louis group; Spergen Hill, Indi-
ana, where the specimens are silicified and impregnated with
iron.

DlCHOTRYPA LYROIDES Ulrich.
PI. LXXVII, flg. 2-2/j.

Zoarium a free lyre-shaped frond, with thick rounded solid
margins, diverging from a more or less rounded base at an
angle of about 60°. The margin is not abruptly thickened, yet
is almost twice the thickness of the celluliferous central portion
of the frond, which varies in thickness between two and three
mm. The height of the example figured must have been at least
five or six cm. Surface with broad, rounded, and variously ele-
vated monticules, arranged in diagonally intersecting series, be-
tween four and five mm. apart, measuring from center to cen-
ter. Summits of monticules occupied by solid, circular or sub-
stellate maculae, bordered by a row of apertures a little larger
than the rest. Apertures circular, slightly oblique, about 0.14

BRYOZOA. 503

mm. in diameter with unequally elevated peristome; arranged
in more or less regular diagonally intersecting series, about
eight in three mm. Interspaces slightly concave, wider than the
diameter of the apertures.

The remarkable zoarial habit of this species distinguishes it
from D. flabellum Rom. and D. elegans, its nearest congeners.
The silicified specimens upon which the species is founded were
collected six or seven years ago by Prof. A. G. Wetherby, and
kindly presented to the author. After a cursory examination
at the time, I laid them aside under the supposition that they
were nothing more than a species of Lyropora encrusted by
some Fistuliporoid. A more careful second examination has re-
sulted in a very different conclusion.

The thickened support is comparable to the solid base of
Evactinopora M. & W.

Position and locality: St. Louis group. Southern Kentucky.

ACTINOTRYPA Ulrich.

(For generic diagnosis see page 386.)

ACTINOTRYPA PECULIARIS Roinmger.

PL LXXVH, flg. 3, 3b.
Fistulipora peculiaris Rominger, 1866. Proc. Acad. Nat. Sci. Phila. p. 123.

Zoarium a thin bifoliate expansion, several cm. in height and
breadth, and from 0.5 to 2.5 mm. in thickness. Surface even,
provided with subcircular broad maculae, appearing minutely
punctured when a little worn, but granular when well preserved.
Macula? level with the general surface, occurring at rather vari-
able intervals, but an average distance of about six mm. pre-
vails. Apertures regularly arranged in diagonally intersecting
series, about six in three mm., floriform, owing to the tooth-
like projections of the internal ridges, with raised peristomes;
about 0.25 mm. in diameter, those nearest the maculae a little
larger. Interspaces of equal or somewhat less width than the
diameter of the apertures. Zooecia at first prostrate, then bent
outward almost at right angles. Occasionally the angle at the
point of bending is prolonged into a short superior hemi.sep-

504 PALAEONTOLOGY OF ILLINOIS.

turn. Soon after bending from 8 to 10 ridges are developed on
the inner surface of the zocecial wall which increase in strength
toward the surface. In tangential sections they appear as sub-
regular tooth-like projections into the zooecial cavity. Inter-
zooecial space filled with layers of lenticular vesicles, of angular
form in tangential sections, which are only partially filled with
solid tissue near the surface. Those resting upon the mesial
laminae a little larger than the others.

Eominger states that the species sometimes occurs in unilam-
inar expansions with an epitheca upon the lower side. I very
much doubt the accuracy of this statement, since none of nearly
one hundred examples seen by me; are in that condition.

This interesting and peculiar species is the only one known to
me having the radial denticles so greatly developed that they
form internal septal ridges. Spinose peristomes are known
among the FISTULIPORID^E, and radial denticles in Fenestella,
Polypora and Pinnatopora, but these are all very superficial
when compared to the radial structures found in A. peculiars.
Still, I regard them all as homologous, and with slight modifi-
cations, accounted for by one explanation; Namely, I believe
that in Actinotrypa, these structures were originally represented
by small spines or tubercles on the peristome of the original
aperture, which acted as support to converging setae, and keep-
ing pace with the gradual elongation or growth of the aper-
ture into a tubular "vestibule," they eventually became septa-
like ridges.

Possibly the genus has nearer relatives among the FISTULI-
PORiDjE, but the essential points of structure, as I now see them
seem to correspond more nearly with those of the CYSTODICTYO-

NID^E.

Position and locality: Keokuk group; Keokuk, Iowa; La-
Grange, Mo., Warsaw and Nauvoo, 111.

TJENIOPORA Nicholson, 1874.

(Geol. Mag. N. S. Vol. I, p. 121.)
(For generic diagnosis see page 386.)

BRYOZOA. 505

T.ENIOPORA OCCIDENTALS Ulrich.
PI. XT.TT, fig. 3— 3C.

This species differs from penniformis Xich., a transverse sec-
tion of which is figured on PI. XLII, fig. 3d for comparison, in
the following- points. The zoariuni is not so wide, but has a
more solid appearance; the median keel is subangular and not
nearly so thin nor so prominent, the non-poriferous margin is
narrower. The apertures of T. penniformis are strongly ele-
vated and arranged in slightly oblique transverse rows (sug-
gesting the name). In this species the arrangement of the
apertures in longitudinal series between low rounded ridges is
more striking than that in transverse rows, while the peristonie
is so little developed that it is scarcely perceptible. Internally
T. penniformis has the interstitial vesicles open, while in the
western form they are filled by solid tissue. T. exigua Nich.,
the only other described species of the genus is a smaller form.

The width of the branches in T. Occident alis, which bifurcate
at intervals of eight mm. or more, is between 2.5 and 3 mm.
The zocecia apertures are subcircular. in four longitudinal rows
on each side of the median keel, with from seven to nine in
three mm. measuring longitudinally. Their diameter increases
from 0.09 mm. in the central rows to 0.13 mm. in the marginal
series, the increase being proportional in each succeeding row.
A shallow depression is often observed in front of the aper-
tures.

Position and locality: Hamilton group; Buffalo, Iowa.

PRISMOPORA Hall, 1881.

(Bry. Up. Held. p. 17.)
(For generic diagnosis see page 386.)

PRISMOPORA TRIFOLIA Rominger.

PI. LXXVH, fig, 4, 4a.
Fif("Ufora irifolia Rominger, 1866. Proc. Acad. Nat. Sci. Phila. p. 122.

Zoariuin consisting- of triangular branching stems, growing
from a large spreading base attached to foreign objects. The
—63

506 PALAEONTOLOGY OF ILLINOIS.

base is traversed by high ridges which frequently coalesce and
form large irregular cup-shaped cavities. The dimensions are
variable, and the width of the faces varies from 5 to 12 mm.,
but one of them usually wider than the others. The inequality
of the faces is often much increased by pressure. Margins sharp,
non-poriferous, essentially parallel. Each face is ornamented by
a series of somewhat curved, elongated, slightly depressed ma-
culae (dimples) extending in a pinnate manner from near the
middle of each face to the non-poriferous margin, about three
mm. long and one mm. or a very little more wide. The sepa-
ration of the dimples varies in different examples, but is ap-
proximately uniform in each. The specimens figured represent
the typical and commonest form. Apertures circular, often a
little oblique, about 0.2 in diameter, with more or less elevated
peristome, arranged in rows nearly parallel with the dimples,
about six in three mm. Interspaces about one-half greater
than the diameter of the apertures. Internal structure as re-
quired by the genus.

There are probably three species of Prismopora in the Keo-
kuk group, which, mainly on account of the indifferent preser-
vation of their fragmentary remains, are now confounded. One
of these (represented by fig. 45) has one of the faces very broad,
and the dimples widely separated and not extending to the
margin. The second has a smoother aspect than the others,
the dimples far apart, and the faces subequal. The third is the
most abundant, and being identical with authentic examples of
Fistulipora trifolia Rominger, forms the basis of the above de-
scription.

Position and locality: Keokuk group. Abundant at Keokuk,
Iowa, LaGrange, Mo., and Warsaw, 111.

PBTSMOPORA MINIMA Ulrich.

PI. LXXVIII, fig. 1-lc.

Zoarium consisting of small, infrequently branching, triangu-
lar stems, with the faces subequal, flat or a little concave, and
about 1.5 mm. wide. Margins sharp, nearly straight and es-
sentially parallel, with the non-poriferous border mostly nar-
row, but at irregular intervals much widened to form smooth

BRYOZOA. 507

semi-circular spaces. Apertures sub-circular or transversely
ovate, irregularly arranged, about 0.15 mm. in diameter, seven
or eight in three mm. Peristome well marked but slightly un-
equal being most elevated on the lower inner side. In tangen-
tial sections the zooecia are depressed pyriform in shape, the
lunarium being well developed. Interspaces quite solid near the
surface, but with vesicular of comparatively large size in the
central part of the branch.

The small size of its branches distinguishes this species from
all previously described. I am indebted to Mr. J. M. Nickles,
of Sparta, 111., for the type specimens, which he washed from
the shales near his home. By this method he has brought to
light many very interesting species, which on account of their
diminutive proportions are easily overlooked when searched for
in the ordinary way.

Position and locality: Lower Coal Measures, Sparta, 111.

SCALARIPORA Hall, 1881.

(Bry. Up. Held. p. 17.)
(For generic diagnosis see page 387.)

r

SCALARIPORA SEPARATA UMch.
PL XLIII, fig. 2.

Zoarium consisting of triangular equilateral stems, each face
having a width of about three mm. Margins sharp, nearly
straight and parallel. Transverse ridges nearly as far apart as
the width of the faces, eleven or twelve in three cm. Portions
of face between margins and ridges depressed, celluliferous.
Apertures about 0.18 mm. in diameter and less than their own
diameter apart; with a faintly elevated peristome; arranged in
more or less regular diagonal rows, nine or ten in three mm.
Internal structure not observed.

The material at hand is insufficient to determine fully all the
characters, but I do not think that collectors will find much
difficulty in identifying the species. In this genus the distance
between the transverse ridges is a constant character, and serves
very well in distinguishing the species. They are separated by

508 PALAEONTOLOGY OF ILLINOIS.

wider intervals in S. separata than in the two Upper Helder-
berg forms described by Hall.
Position and locality: Hamilton group, Thunder Bay, Mich.

SCALARIPORA APPROXIMATA Ulrich.
PL XLIII, fig. 3.

This species differs from the preceding in being somewhat less
robust, the margins slightly serrated and the cell apertures
somewhat more approximated. A more striking peculiarity is
that the transverse ridges are very close set, there being about
twenty in two cm.

Position and locality: Hamilton group; occurs with the pre-
ceding at Thunder Bay, Mich.

EVACTINOPORA Meek and Worthen, 1865.

(Proc. Acad. Nat. Sci. Phila. p. 165.)
(For generic diagnosis see page 387.)

This remarkable genus of Bryozoa is known only from the
Burlington and Keokuk limestones by three species in the for-
mer and one in the latter. The free habit of growth, the radial
arrangement of the bifoliate fronds, and the comparatively
large proportion of the non-celluliferous areas are the principal
peculiarities of the genus. Although very striking, these differ-
ences are nevertheless not so important as they may at first
appear, since the minute structure and the elemental construc-
tion of the zoarium does not depart in any essential point
from the plan that prevails in the family. Thus, while in Cys-
todictya, Dichotrypa and Coscinium, the zoarium consists of
two simple folia grown together back to . back, and in Prismo-
pora, Scalaripora and Glyptopora, of three such double folia
diverging from a central line or axis, these are from four to
eight radially arranged double leaves in Evactinopora. In the
minute structure of the folia there is little or nothing to dis-
tinguish the genus from any of the other genera of the family.

BRYOZOA. 509

EVACTINOPORA RADiATA Meek and Worthen.

PI. LXXm, flg. 3, 3a.

Eractinopora radiata M. & "W. 1865. Proc. Acad. Nat. Sci. Phila, p. 165.
Evact inopora radiata M. & W. 1868. Geol. Surv. Ill voL 3, p. 502, PL XVII, flg. 2o, 2&.
Eractinopora radiata Ulrich, 1884. Jour. Cin. Soc. Nat Hist. voL 7, p. 42, PI. H, flg. l-le.

Zoarium ellipsoidal in outline when complete, consisting of
from six to eight bilaminar vertical folia, arranged in a radiate
manner. In the basal half of the zoarium the folia or rays
are united and much thickened by a deposit of carcareous ma-
terial, so that the "body" of the star, as seen in a basal view,
is comparatively strong and the rays correspondingly short
and blunt. The edges of the rays are preserved in the regularly
rounded base as angular converging ridges, separated by at
first very shallow, then gradually deepening and widening fur-
rows. At a point about midway between the summit and base
where the rays become free, they are acutely elliptical in trans-
verse section, four or five mm. in width, with a non-poriferous
border on each edge, the outer one a little the widest; from
this point the margins are parallel for a short distance, then
converging slowly, till they meet at the narrowly rounded ex-
tremity. The whole base for nearly one-third the distance up
the side of the rays, is non-poriferous at the surface, the zooe-
cia apertures here being covered by a granulo-striate deposit of
sclerenchyma, decreasing in thickness upward. Zooecia prostrate
at first, then arising from the mesial laminae, proceed to each
surface of the rays at an angle of about 45°. Apertures sub-
circular, oblique, the lower margin being most elevated; about
Q.2'2 mm. in diameter, the same distance or less apart, arranged
in not very regular intersecting series, with eight or nine in
three mm. Interspaces occupied by small lenticular vesicles, a
few of which remain open, especially on each side of the mesial
plane, the rest being filled and obscured by vertically perforated
dense tissue, the perforations appearing in tangential sections
as exceedingly numerous minute dark spots. Scattered among
them are other spots of large size, that resemble acanthopores,
in having the central portion lucid. Lunarium inconspicuous.

Position and locality: Keokuk group. King's Mountain. Ky..
and at an undetermined locality in Missouri (M. & W.).

510 PALEONTOLOGY OF ILLINOIS.

EVACTINOPORA SEXRADiATA Meek and Worthen.

PL LXXIII, fig. 2-2&.
Evactinopora sexradiata M. W. 1868. Geol. Surv. 111. vol. 3, p. 502.

This species differs from the preceding in being a little wider
and much more depressed, and constant in having only six
rays. The zooecia apertures are also larger, there being only
about six in three mm. In a basal view the rays are much
longer and more slender. Beside the whole zoarium appears to
be much more delicate in its proportions.

The example figured by Meek and Worthen (loc. cit.) having
only five rays, does not belong to this species, but to E.
q uin q ueradiata.

Position and locality: Burlington group. Burlington, Iowa.

EVACTINOPORA QUINQUERADIATA Ulrich.

PL LXXIII, flg. 1.

Zoarium with five thin bifoliate rays, varying in different ex-
amples in thickness from 2 to 4 mm., in width from 20 to 60
mm., and in height from 15 to 40 mm. The body formed by
the union of the rays comparatively very small. Kays increas-
ing very gradually in thickness from the free outer margin to
the body, sharp on the lower margin, which curves very slightly
upward toward the extremity, where it forms nearly a right
angle with the more curved upper margin. Zooecia apertures
small, sub-circular, about twice their width apart, arranged in
regular intersecting series, about six in three mm.

This species is readily distinguished from E. sexradmta, M. &
W., by its much larger size, five instead of six rays, and com-
paratively more depressed form.

A section in the rock showing only the upper portion of the
rays of an example of this species was erroneously figured in
Vol. Ill, on plate XVII, as E. sexradmta, by the authors of
that species.

Position and locality: Burlington limestone. Burlington,
Iowa, and Montezuma, 111.

BRYOZOA. 511

EVACTINOPORA GRANDis Meek and Worthen.

PI. LXXHI, fig. 4.
Evactinopora grandis M. & W. 1868. Geol. Surv. of 111. vol. Ill, p. 503. PL XV.flg. 2a, 26.

This species, like E. quinqueradiata, has very much larger
rays than the other species. They attain in the largest examples
a width of eight cm., but in a small specimen before me, they
are only four cm. wide. Their entire height has not been ob-
served, but I do not think it was as great as the width; their
greatest thickness varies from 4 to 8 mm., and the taper to
the outer extremity is very gradual. Far up, the axis is rhom-
bic in shape, and the rays are very much contracted immedi-
ately after leaving the axis. The rays are four in number, ex-
tending out at right angles to one another. Zooecial tubes
oblique, the apertures small, round, regularly arranged in quin-
cunx, separated by interspaces about equal to t\vice their di-
ameter; five or six in three mm.; interspaces filled with vesicu-
lar tissue, the vesicles open except near the surface, where they
are as usually filled with a deposit of sclerenchyma.

There are several peculiarities in the minute structure, but
the preservation of the Bryozoa in the Burlington limestone is
rarely so satisfactory that they can be determined.

Luckily the basal portion of the zoarium usually holds to-
gether, so that the three species found in this rock can be dis-
tinguished by the number and form of the rays.

Position and locality: Burlington limestone, Burlington, Iowa.

GLYPTOPORA Ulrich, 1884.

(Jour. Cin. Soc. Nat. Hist VoL VII, p. 39.)
(For generic diagnosis see page 387.)

During the preparation of this work I have had an abundance
of material for study, and in many instances I have been en-
abled to give a better definition of genera previously proposed
by me. This genus required perhaps more time than any other
to master fully. The principal difficulty was encountered in the
determination of the method of growth of such forms as G.
keyserlingi and G. punctipora. The fragmentary remains,

512 PALEONTOLOGY OF ILLINOIS.

though abundant, proved very deceptive, and it was only after
much search that zoaria sufficiently complete to show tlie plans
were obtained. After this point was determined it became clear
that the genus was divided into two unequal groups. In the
smaller one, containing only G. plumosa and G. sagenella, with
its two varieties, the zoarium forms an irregular bifoliate ex-
pansion, having both surfaces divided into larger or smaller
cup-shaped cavities by the bifurcation and coalescing of "the
sharp-edged high ridges. These ridges are composed of two
layers of zo(Bcia grown together back to back. The other group
comprises the balance of the species, excepting, G. nrichelinitt,
which is intermediate, its zoarium being primitively unilaminar
as in this group, while the upper surface of the expansion is
precisely like that in the first section. In G. keyserlingi and
the other species the zoarium differs from tha.t of G. sagenella
in having the ridges developed to such an extent that they
form large bifoliate expansions. These diverge from a small
basal expansion, covered on the lower side by a strongly
wrinkled epitheca.

The identification of Prout's species was another difficult task,
but, at last, all were known with the exception of his Coscinium
wortheni. No species is known to me that is strictly identical
with the figure given in Vol. 2 of these reports. I am, how-
ever, strongly inclined to regard the species as founded upon
the basal portion of G. keyserlingi. An examination of the
original specimens alone can determine the point beyond dis-
pute.

GLXTTOPOKA PLUMOSA Prout.

PI. LXXVIH, fig. 3-3c.

Coscinium plumosum Prout, 1860, Trans. St. Louis Acad. Sci. vol. I, p. 572.
Coscinium plumo sum Prout, 1866. Geol. Surv. III. vol. II, p. 414. PI. XXII, fig. 3, 3k.

Zoarium consisting of one or more bilaminar thin expansions,
arising from a common attached base, each having both sur-
faces traversed by strong bifurcating and coalescing ridges, so
as to enclose large but rather shallow' concave spaces or cups,
varying so far as observed, in length from 20 to 30 mm., and

BRYOZOA. 513

in width from 12 to 32 mm. The surface of the cups slopes
gradually up to the base of the sharp edged ridges. At the
bottom there is usually a long and narrow depressed macula
or ''dimple," and on each side arranged in a more or less dis-
tinctly pinnate manner, are a series of long, curving, sharply
depressed, parallel dimples, about 1.2 mm. wide, and from 7 to
16 mm. long.

The ridges on one side of the expansion correspond to the
central depressions on the other. Zooecia apertures very slightly
oblique, sub-circular or oval, 0.15 to 0.20 mm. in diameter, ar-
ranged in from four to eight (usually five) alternating rows
between the dimples, about nine in 3 mm. Peristome moderate,
somewhat more elevated on one side than on the other. In-
terspaces depressed when perfect, usually about half as wide as
the apertures. In thin sections the zooecial tubes have moderately
thick ring-like walls, a portion of the wall being distinguishable
from the rest as the lunariuni by its lighter color. A large
number of small vesicles occupy the interspaces between the
zooecia walls.

The specimen originally figured by Dr. Prout was apparently
somewhat crushed, and scarcely shows the characteristic plu-
mose arrangement of the dimples. He also describes and illus-
trates the form here described as G. sagenella, var caliculosa, as
the opposite or "cupuliferous" side of G. plumosa. This is evi-
dently a case of faulty observation since the two sides of the
expansion are approximately alike.

Position and locality: Warsaw beds. Rather rare at War-
saw. 111., and Barrett's Station, St. Louis Co., Mo.

GLYPTOPOBA SAGEXELLA Prout.

PI. LXXVin, fig. 6, 6a.

Coscinium sogenella Prout, 1859. Trans. St. Louis Acad. Sci. vol. I, p. 573.
Coscinium sagenella Prout, 1866. Geol. Surv. 111. vol. H, p. 415, PI. XXII, fig. 5. 5a.

Zoarium erect, higher than wide, the dimensions varying with
age, the largest seen being about eight cm. high and four cm.
in its greatest width. Both sides with strong sharp ridges, di-
viding and coalescing so as to enclose concave depressions or

-64

514 PALEONTOLOGY OF ILLINOIS.

"cups." The principal ridges at any rate, always correspond
with a depression 011 the opposite side, and have a more or
less decided longitudinal arrangement. The cups, especialty the
central ones, are several times longer than wide, both dimen-
sions being very variable in even the same example. Generally
those near the lateral margins of the zoarium are shorter and
directed outward. The length of the depressions so far as ob-
served, varies from 4 to 30 mm., the width from 3 to 7 mm.,
the depth from 1 to 2.5 mm. Summit of ridges sharp, and
non-poriferous. Surface of cups with rather inconspicuous
elongated maculae, which are somewhat depressed and best
shown in the examples with the shortest cups. Zooecia with
sub-circular apertures, surrounded by an. unequally elevated
peristorne, about 0.18 mm. in diameter, an equal or less dis-
tance apart, and averaging eight in three mm., with no recog-
nizable plan of arrangement. Zooecial tubes with thin walls, at
first prostrate along the mesial plate and somewhat flattened,
then bending with a moderate curve and becoming rounded,
proceed to the surface at an angle varying somewhat from the
perpendicular. A few diaphragms occasionally developed in the
tubes. Lunarium present but not always showing plainly. Ve-
sicles variable in shape and size, shallow, their width almost
equal to the diameter of the tubes, those along the median
lamina larger than the others. There is a thin deposit of light
colored sclerenchyma upon their floors.

In its typical form this species is readily distinguished from
all the others by the elongated "cups." The two forms next
described are likewise easily recognized when typical, but as \ve
sometimes meet with examples which seem to combine the char-
acters of two or even all three, I have thought it best to indi-
cate their intimate relations by giving them only the rank of
varieties under G. sageneUa.

Position and locality: Keokuk group, at Bentonsport, Iowa;
Warsaw beds, at Warsaw, 111.

GLYPTOPORA SAGENELLA var. CALICULOSA Ulrich.

(Not figured.)

In this variety the zoarium is wider, more lax, and has a
more delicate aspect than in the typical form of G. sagenella, the

BRYOZOA. 515

ridges are thinner, being abruptly elevated from the nearly flat
bottom of the cups. The cups are also much shorter, many of
them being hexagonal in outline and but little longer than
wide. In an average example their dimensions may vary as
follows: the width from 3 to 7 mm.; the length from 5 to 10
mm.; the depth from 1.5 to 2.5 mm. The dimples are also
much better defined and more depressed, one placed near the
center of the cup being especially distinct and generally of elon-
gate stellar form. A number, varying with the size of the cup,
are arranged in a subradial manner around the central one,
and extend up the steep slopes of the ridges to the sharp non-
poriferous edge. The zooecial apertures are also shown more
closely approximated.

Position and locality: Warsaw beds. Common at Warsaw,
111. A small example of this variety is figured in Vol. 2 of this
Survey, as the opposite side of Coscinium plumosum Prout,
obviously in error.

GLYPTOPORA SAGENELLA var. LATA Ulrich.

PL LXXVni, fig. 4.

This variety differs from typical G. sagenelhi in very nearly
the same manner as does the var. m Jiculosa, its principal pecu-
liarities being the much wider cup and the more elongated and
often curved dimples. The figure represents one side of an aver-
age example.

Position and locality: Warsaw beds. Xot rare at Warsaw, El.

GLYPTOPORA MICHELFXIA Prout.

PI. LXXVm, fig. 8-86.

Coscinium michelinia Prout, 1800. Trans. St. Louis Acad. Sci. Vol. I, p. 573.
Coscinium micheUniaProut, 1866. Geol. Surv. El. Vol. 2, p. 414, PI. XXH, fig. 4, 4o.

Zoarium encrusting or free, with a wrinkled epitheca on the
lower side. Upper surface divided into larger or smaller, deep,
polygonal, cup-shaped cavities, enclosed by prominently elevated,
sharp ridges, the summits of which, when in a good state of

516 PALEONTOLOGY OF ILLINOIS.

preservation, are serrated. The cups vary greatly in size, but
are approximately equal on each example. The average width
in the two largest specimens seen is about 12 mm., while in
others it is only about 9 mm. At the bottom of the cups
there is a more or less elongated depressed solid macula. Sim-
ilar narrow maculae extend up the sides of the ridge at inter-
vals apart of 2 mm. more or less. These maculae usually oc-
cupy corresponding positions on each side of the ridges, and
being depressed terminate before reaching their summits. The
serrated character of the comb of the ridge is due to this cir-
cumstance. The spaces between the maculae is uniformly occu-
pied by the zooecia apertures. These are sub-circular, about
0.16 mm. in diameter, and nine in 3 mm., separated by inter-
spaces^equal in width to their diameter.

The upper surface of this peculiar species closely resembles
the varieties of G. sagenella. Yet there is an important differ-
ence in their respective modes of growth. In that species the
zoariuni is celluliferous on both sides, while in this the lower
surface is covered with an irregular epitheca. In other words
one may be said to be bifoliate, the other simple and lamellate.
The zoarium of G. michelinia, also attains a much greater
thickness than any of the other species of the genus, the great-
est observed being about 10 mm.

Position and locality: Warsaw beds, Warsaw, 111., and Bar-
rett's Station, St. Louis Co., Mo.

GLYPTOPORA PINNATA UMch.

PI. LXXVIII, fig. 2.

Of this species I have seen only the imperfect example figured.
Judging from this the species must have been on the order of
G. keyserlingi Prout, and G. megastoma Ulr. At the junction
of the foliar expansions the zoariuni is strong and of triangu-
lar form in transverse section. The zooecia apertures extend
uniformly over this portion, there being no non-poriferous strip.
The maculae are solid and regularly arranged in diagonal series,
and in a pinnate manner on each side of the line of junction of
the leaves. They are somewhat elevated, but this may be due

BRYOZOA. 517

to the wearing away of the intermediate spaces. Diagonally
they are about 5 mm. apart, measuring from center to center.
The zooecia are similarly arranged, about ten in 5 mm., with
comparatively large sub-ovate apertures, about 0.35 mm. in
diameter, separated by thin interspaces. In better preserved
specimens the apertures would probably be smaller and the in-
terspaces correspondingly thicker.

The species must be closely related to G. megastoma, of the
Keokuk group.

Position and locality: Burlington limestone. Sagetown, Hen-
derson Co., 111.

GLYPTOPORA KEYSERLINGI Prout.

PI. LXXVni, fig. 4-4b.

Coscinium keyserlingi Prout, 1858. Trans. St. Louis Acad Sci. vol. I. p. 269, PI. XV

fig. 4-4a.

? Coscinium wortheni Prout, 1860. Ibid vol. I, p. 571.

1 Coscinium wortheni Prout, 1866. Geol. Surv. El. vol. 2, p. 412, PI. XXTT, fig. l, la.

The complete zoarium consists of thin upright bifoliate ex-
pansions, arranged in such a manner that they enclose large
and rapidly expanding hexagonal cups. The under side of the
dome-shaped or flattened base is covered with a wrinkled epi-
theca, and the bifoliate fronds which extend up from it are
equivalent to the ridges in G. micheliniti. At the angles of
junction of the fronds, which vary in thickness from 0.25 to
1.0 mm., there is a narrow depressed solid strip on each side,
making the junction very frail. In consequence it is only in ex-
tremely rare instances that the foliate expansions are found
joined together, and in nine cases out of ten we deal only with
fragments of one of the sides or partitions of the cups. Figure
4 represents a small but nearly complete side, and shows the
form and distribution of the lanceolate or acutely elliptical
dimples and zooecia. Its width is comparatively greater than
usual, the angle formed by the two non-poriferous edges being
a little over 90°. In other examples the angle varies from that
degree down to 50°. The dimples are from 4 to 6 mm. long,
1.5 to 2.0 wide, and generally a little the widest in their upper
half, and somewhat acutely terminated below. Their surface as

518 . PALAEONTOLOGY OF ILLINOIS.

well as the non-poriferous margins, are marked with fine granu-
lose, longitudinal striae. Apertures irregularly sub-circular or
oval, oblique, with strongly projecting irregularly toothed hood,
the average about 0.2 mm. in diameter, those bordering the
dimples somewhat larger; from ten to twelve occur in 5 mm.,
measuring along the moderately regular diagonal and longitu-
dinal series. Interspaces somewhat rough, depressed, usually
of less width than the apertures. In thin sections the zooecial
tubes are thin-walled, at first prostrate; after bending they
continue in a somewhat oblique course to the surface. Vesiculae
small, very numerous, filled up with solid tissue towards the
surface.

Position and locality: Keokuk group. Rather common at
Warsaw and Nauvoo, 111.; Keokuk and Bentonsport, Iowa, and
at other localities.

V

I

GLYPTOPORA ELEGANS Prout.

> PL LXXVIII, Fig. 10-10e.

Coscinium elegans Prout, 1860. Trans. St. Louis Acad. Sci. Vol. 1, p. 572.
Coscinium elegans Prout, 1866. Geol. Sur. 111., Vol. 2, p. 413. PL XXII, Fig. 2-2a.

In this species the growth and general construction of the
zoarium is precisely as in G. keyserlingi, from the Keokuk
group. The only differences so far observed are, (1) that the
cups are more numerous, proportionally smaller, and the bi-
foliate partitions narrower; (2) the dimples prevailingly nar-
rower, and (3) the zooecia apertures are smaller, their diameter
varying from 0.15 to 0.2 mm., with from 12 to 14 in 5 mm.
The smaller size of the apertures is the most important as well
as the most constant of the differences.

Position and locality: Warsaw beds at Warsaw, 111.

GLYPTOPORA MEGASTOMA III rich.

PL LXXVIII, Fig. 5-5a.

In its manner of growth and general appearance this species
resembles G. keyserlingi Prout, but the following points of dif-
ference are so obvious that there is little danger of confusion
between them. The dimples or maculae are shorter and not de-

BRYOZOA. 519

pressed, sometimes even occupying the summits of broad eleva-
tions. The zon-cia apertures are direct and sub-circular in out-
line, with the lunarial side usually somewhat straightened and
pinched in the middle,the peristome thinner and sub-equally
elevated, the apertures considerably larger, those of the average
size being about 0.25 mm. in diameter, while some of those in
the immediate vicinity of the maculae are frequently 0.4 mm. in
width. Nine and one-half or ten of the ordinary zocecia aper-
tures occur in 5 mm, At the junction of the leaves they are
somewhat thickened and there is no narrow depressed non-
poriferous strip at the line of junction. The interspaces and
macula? appear rather coarsely granular or pitted at the surface.
Internally they are occupied by larger and fewer vesicles. These
differences seem amply sufficient to distinguish the two species.
A nearer congener is probably found in G. pinnata of the Bur-
lington limestone.

Position and locality: Keokuk group. Occurs at Warsaw and
Nauvoo in 111., and Keokuk and Bentoiisport in Iowa.

GLYPTOPORA PUNCTIPORA Ulrich.

PI. LXXVUI, Fig. 9-9a.

In the manner of growth and general aspect this species is
precisely like G. keyserlingi, and G. elegans, with the single ex-
ception that the maculae or dimples are smaller, and very little
impressed, usually appearing on a level with the general plane
of the surface. They are consequently a much less conspicuous
superficial feature than in those species. The zooecial apertures
are small, compressed, somewhat kidney-shaped, the longer
diameter about 0.2 mm.; arranged in regular curved diagonally
intersecting series, 11 or 12 in five mm. The apertures occupy
the summits of rounded confluent pustules, which are a little
the largest in the vicinity of the maculae. The width of the
interspaces usually equals about one and a half times the long
diameter of the apertures. In sections the zooecia are thin-
walled, the lunarium fairly distinct, the vesicles numerous and
generally in two series between the zooecia. Several sections
show very plainly the minute perforation in the vesicle covers.

520 PALEONTOLOGY OF ILLINOIS.

Fragments of this species might be confounded with a St.
Louis limestone species of Dichotrypa, but the nearly complete
example before me clearly proves the species to be a Glypto-
pora.

Position and locality: Chester group. Rare at some locality
in Monroe Co., 111.

EURYDICTYA Ulrich.

(For generic diagnosis see page 389.)

This genus includes a small group of Silurian Bryozoa that,
though intimately related to Stictopora Hall (Rhinidictya
Ulrich), it seems desirable to distinguish from that genus. The
broad and undefined zoarial expansion pertaining to the sev-
eral species gives to them a very different aspect from that
presented by the parallel margined, dichotomously divided,
narrow stipes, so strictly adhered to by the true species of
Stictopora. The two genera stand precisely in the same relation
to each other as Cystodictya and Dichotrypa.

In addition to the three species here defined the genus will
include Phsenopora multipora Hall, of which a full description
is given in my "American Palaeozoic Bryozoa," (Jour. Cin. Soc.
Nat. Hist., vol. V, p. 171). At that time I stated the species
was most probably not congeneric with typical Phsenopora
Hall. That supposition has since been verified.

EURYDICTYA CALHOUNENSIS Ulrich.

PI. XXX, Fig. 4-4c.

Zoarium an expanded frond; thickness two mm. Surface
smooth with maculae which are irregular in size, elevation, and
distribution. Zooecia arranged in longitudinal series; the super-
ficial apertures have the appearance of being between raised
longitudinal lines; generally oval, occasionally sub-circular, be-
tween six and seven in two mm. measuring lengthwise. Inter-
spaces between the ends of two successive apertures about equal
to or less than the long diameter of the apertures. Minute
tubuli, appearing on the surface as granules, are arranged in a
flexuous line between adjacent series of cells and in one or two
irregular rows in the end interspaces. Macute consist of a large

BRYOZOA. 521

number of these minute tubuli. Superior hemiseptum very pro-
nounced. This form in common with some others shows a
secondary layer growing upon the primary layer of cells, but
growing in reversed order, zocecium above zooecium, and macula?
above maculae. This is best observed in longitudinal sections
(fig. 4c).

Externally this species resembles E. multipora Hall, but the
cell apertures are more rounded, and the internal structure
is very different. Internally it is considerably like E. montifera,
but the pronounced monticules of that species are sufficient
without other points of difference to distinguish the two.

Position and locality: Trenton group; Port au Gres, Calhoun
Co., 111.

EURYDICTYA MONTIFERA Ulrich.
PL XXX, Fig. 3-3d.

, Zoarium an expanded frond, several cm. in height and breadth
and 0.15 to 0.20 mm. in thickness. Surface provided with con-
spicuous monticules having solid apices, and with no marked
arrangement, two or three mm. apart. Primitive portion of
zooecia very short, vestibular portion of tube almost at right
angles with the surface. Vestibules 0.15 to 0.18 mm. in diame-
ter, inter- vestibular space about the same as the diameter of the
vestibules. Apertures oval, from 0.15 to 0.22 (nm. in'their long
diameter, nine longitudinally and ten diagonally in three mm.,
arranged in longitudinal and diagonally intersecting series.
Zooecia surrounded by a single row which sometimes becomes
doubled at the angles, of minute tubuli, appearing on the
surface as granules. The macula? are composed of a large num-
ber of these minute tubuli having an indefinite radial arrange-
ment. Occasionally there is a superposed layer growing in the
reversed direction. Superior hemiseptum rather pronounced.

In some respects this species is closely related to E. calhoun-
ensis, but is readily distinguished from that form by the smaller,
and differently arranged median tubuli and the montiferous
surface. The zocecia of that species also have a dark band sur-
rounding the visceral cavity; this band is wanting in E. monti-
fera.

Position and locality: Cincinnati group, Wilmington, 111.
—65

522 PALAEONTOLOGY OF ILLINOIS.

EUEYDICTYA STERLINGENSIS UMch.
PI. XXX, Fig. 2-2a.

Zoarium an irregular frond, sometimes appearing to branch.
Surface smooth, destitute of maculae. Zooecia arranged in very
regular longitudinal and diagonally intersecting series. Aper-
tures round, about 0.12 mm. in diameter, six vertically and
seven diagonally in two mm.; separated by very wide inter-
spaces, about 0.20 mm. wide, which are filled with a great
number of minute granules arranged in several series about each
aperture.

The form of growth of this species is like that of E. multipora
Hall, but that species has the interspaces very narrow, and
cells so arranged as to appear between elevated longitudinal
ridges, while the minute tubuli form a longitudinal line between
the adjoining vertical series of apertures and never occupy the
end interspaces.

Position and locality: Cincinnati group, Sterling, 111.

PACHYDICTYA Ulrich, 1882.

(Jour. Gin. Soc. Nat. Hist. Vol. V, p, 152.)
(For generic diagnosis see page 390.)

This genus proves to be one of the most important divisions
of the lower Palaeozoic Bryozoa. The three species that were
known to me when the genus was proposed, have since been re-
inforced by nineteen others, varying in time from the base of
the Trenton to the Lower Helderberg. The form of the zoarium
varies greatly in the different species, some being narrow rib-
bon-like, a few wider and stronger, while others again form
broad undulating expansions of considerable thickness. In all,
however, the minute structure is remarkably constant. The ex-
tremes in this respect so far noticed, are furnished by the five
species here described. The structure of P. robusta Ulr., the type
of the genus, is intermediate between that of P. everetti and
P. firma, while that of P. gig-ant ea, is very much like that of
P. acuta Hall, P. occidentalis Ulr., F. obesa Foerste, and sev-
eral other species. P. splendens suggests Eurydictya, but not
very strongly.

BRYOZOA. 523

PACHYDICTYA EVERETT: Clrich.
PL xxxm. flg. i-if .

Zoariuin an undulated frond, several cm. in height and width,
three mm. or a little more in thickness. Surface smooth, desti-
tute of maculae. Cell apertures suboval to hexagonal in shape,
forming diagonally intersecting as well as longitudinal rows,
from 0.18 to 0.25 mm. in longitudinal diameter, about five in
two mm. diagonally, and four longitudinally. Occasionally a
cell aperture has preserved an opercular structure. Zooecial
tubes rather thin-walled, largely in contact, with no straight
or flexuous lamella separating them, provided with closely set
diaphragms. The interstitial vesicles are angular, comparatively
few, mainly occupying the angles between the zooecia and re-
maining so far as observed, open to the surface. In deep tan-
gential sections the walls are exceedingly thin and appear to
contain a series of exceedingly minute tubuli. The minute
tubuli between the median laminae of the frond are a more de-
cided structure than in any other species of the genus yet ex-
amined.

This species preserves all the essential characters of the genus,
yet the open interstitial spaces and the great abundance of dia-
phragms are curious features. The smooth surface unmarked
with maculae, and the regular and comparatively large sized
sub-angular cells distinguish it from other species of the genus.

Position and locality: Trenton group; Dixon, 111.

PACHYDICTYA SPLENDENS Ulrich.

PL XXXI, flg. 2g, and PL XXXH, flg. 1-lb.

Zoarium consisting of undulated flabellate fronds, or of broad
irregular dividing branches, 1 to 3 cm. wide, as much as 15
cm. high, and 4 mm. or less in thickness. Surface smooth with
scarcely noticeable clusters of cell apertures separated by thicker
interspaces and a little more prolonged than ordinarily. Cell
apertures oblique, narrowing toward the upper end, with peri-

524 PAl^ONTOLOGY OF ILLINOIS.

stome or lip upon the lower margin, arranged in longitudinal
and diagonally intersecting lines, the longitudinal arrangement
most prominent. Apertures six longitudinally, seven and a
half diagonally in two mm., from 0.16 to 0.2 mm. in longitu-
dinal diameter. Zocecial tube* at first prostrate, then bending
outward proceed to the surface at an angle of 45°; provided
with two or three diaphragms. Interzooecial spaces at first oc-
cupied by a vesicular structure which is soon afterwards re-
placed by solid calcareous tissue, pierced by minute tubuli; the
latter are arranged very closely in a flexuous line, and at the
surface appear as minute granules occuping the ridges between
the longitudinal series of cells; also found in the end spaces.

This species is intermediate in its characters between P. firm a
and P. gigantea. From both it differs in the obliquity of the
cell apertures, from the former in the absence of monticules or
distinct maculae, in having longer and somewhat larger cells,
and the median tubuli arranged in regular flexuous lines, from
the latter in having much thinner walled zooecia, and somewhat
different grow7th.

Position and locality: Cincinnati group; very abundant at
Wilmington, 111.

PACHYDICTYA GIGANTEA Ulrich.

PI. XXXI, fig. 3-3e.

Zoarium a very large undulated frond, the type specimen
which is not complete, being 10.5 cm. in height, 5 cm. in its
greatest width, and about 3.0 mm. in thickness. Surface with
maculae, arranged in more or less regular series, sometimes
broad and low, usually level with the general surface, occasion-
ally a little depressed, about three mm. apart. Apertures
arranged with great regularity in longitudinal and diagonal
series, approximately oval, surrounded by a slightly elevated
peristome, from 0.15 to 0.25 mm. in their longest diameter,
those immediately surrounding the maculae being the largest
with about eight in three mm. longitudinally. Zooecial tubes
but little prostrate at their origin, curving outwards in their
course to the surface, where they open with nearly direct aper-

BRYOZOA. 525

tures; walls thick, ring-like; two or three diaphragms developed.
Interzooecial space at first occupied by vesicular tissue, which
afterwards becomes obsolete. In tangential sections the minute
tubuli are quite inconspicuous (only in longitudinal series), and
the maculae have a solid appearance.

The large subfrondescent growth, and thick ring-like walls,
distinguish it with other characters from P. splendens and P.
firma.

Position and locality: Cincinnati group; Wilmington, 111.

PACHYDICTYA FERMA Ulrich.

PL XXXI, fig. 2-2f.

Zoarium consisting of usually twisted, compressed branches,
5 to 10 cm. in height, 10 to 15 mm. in width and 5 to 8
mm. in thickness. Transverse section lenticular. Surface gen-
erally marked with small, conical monticules, with solid apices,
arranged in quite regular diagonal intersecting series. Zooecial
tubes gradually curving outwards until they are nearly direct
at the surface, provided with an occasional diaphragm. Zocecia
surrounded by one or two series of minute tubuli which appear
as granules upon the surface when well preserved. Apertures
with but little regularity of arrangement, sometimes subcircu-
lar, usually oval, from 0.15 to 0.20 mm. in diameter, about six
in two mm. measuring lengthwise. Maculae subsolid with a
variable number of minute tubuli aggregated in them. Inter-
zooecial space provided in the deeper portions -with vesicular
structure. This is afterwards replaced with solid calcareous
tissue.

The comparatively thick branches, small pimple-like monti-
cules, large number of granules, and lack of orderly arrange-
ment of the apertures, (though sections show the zooecia to be
arranged in longitudinal series), are the most marked charac-
ters of this species. In the width of the branches it resembles
P. robust a, but ample differences in cell arrangement distinguish
them.

Position and locality: Cincinnati group, Wilmington, 111.

526 PALAEONTOLOGY OF ILLINOIS.

PACHYDICTYA FENESTELLIFORMIS Nicholson.

PI. XXXI, fig. 1.

Ptilodictya fenestelliformis Nieh., 1875. Ann. & Mag. Nat. Hist. 4 ser. Vol. 5, p. 181.
PI. XIV, fig. 5-5b.

Ptilodictya fenestelVformis Nich., 1875. Pal. Ohio, Vol. II, p. 263, PL XXV, figs. 8, 8b.

Ptilodictya fenestelliformis Nich., 1875. Kept. Pal. Ontario, p. 14.

Phcenopora fenestelliformis Ulrich, 1882. Jour. Gin. Soc. Nat. Hist. Vol. V,P1. VIII, fig. 8.

This species is exceedingly abundant at Wilmington, 111. Its
ramose habit of growth and comparatively small branches dis-
tinguishes it from the four species of the genus with which it is
associated, one of them still undescribed.

The figure represents a small but nearly complete example of
a variety which I propose to call corticula, from the fact that
the zooecia apertures of the lower half or more of the zoarium
are covered by a more or less thick, and finely granulose or
striate, solid deposit. The zoarium of the variety is larger and
the branches wider and much stronger than in the typical form.
In both the surface exhibits sometimes conspicuous, at the other
times faintly defined smooth spots. The zooecia apertures are
small, widely separated, surrounded by a peristome, ranged in
longitudinal rows, with twelve or thirteen in 5 mm. The inter-
nal structure is similar to that of P. gigantea.

P. fenestelliformis and its var. corticula, belong to a group
of closely related species, comprising, besides, P. acuta Hall and
P. occidentalis Ulr., from the Trenton, and P. biturcata VanCleve
(Hall) and P. turgida Foerste, from the Clinton.

Position and locality: Cincinnati group, Wilmington, 111.

EUSPILOPORA Ulrich.

(For generic diagnosis see page 389.)

EUSPILOPORA SERRATA Ulrich.

PI. XLIII, fig. 4-4h.

Zoarium a narrow stipe, branching dichotomously as a, rule,
with serrate margins, width about two mm., thickness 0.8 mm.

BRYOZOA. 527

attached to foreign bodies by a slightly expanded base. Cell
apertures arranged in four or five longitudinal series, occupying
the center of the branch, sending off alternate lateral series, com-
posed of three or four irregular rows extending to the margins.
Between these lateral series are concave granulo-striate non-cel-
luliferous spaces. The elevated ridges between the longitu-
dinal series bear a considerable number of blunt spines. Cell
apertures about seven in two mm. measuring down the rows;
oval, about 0.10 mm. in longer diameter; width of end spaces
about one and a half times the diameter of the apertures. Zo-
oecial tubes prostrate for a short distance, then abruptly bent
outward. Between the zooecia are vesicles or mesopores, which
do not show at the surface and are provided with very thick
diaphragms. The interspaces between the zocecia and the non-
cellnliferous portions are occupied by exceedingly numerous
minute tubuli.

The peculiar arrangement of the zooecia distinguishes this spe-
cies from all Stictoporoid Bryoza known to me from the Ham-
ilton group, with the exception of Stictopora palmipes Hall.
That species, if I have correctly identified it, is closely allied to
the one above defined, and clearly congeneric with it. It differs
in being wider and scarcely branched, nor have I found it at
Buffalo, Iowa, where E. serrata is fairly abundant.

These species I regard as quite distinct from Stictopora, the
minute structure and the arrangement of the zooecia being very
different from what we find in typical species of that genus.
The following species does not belong in this association, but
is provisionally placed here till we can find a more fitting re-
ceptacle for it.

EUSPILOPORA ? BAKRISI UMcll.

PI. XLIII, Fig. 5-5d.

Zoarium dichotomously branched, stipe with non-celluliferous
margins, from two to four mm. wide, and one to four mm. in
thickness. Transverse section strongly double convex. Aper-
tures sub-polygonal or sub-circular, slightly oblique, 0.2 mm. or
a little less in diameter, between eight and nine in three mm.,

528 PALEONTOLOGY OF ILLINOIS.

rather irregularly arranged. Interspaces considerably less than
the diameter of the apertures in the central portion, but greater
towards the margins of the stipe. Zocecial tubes long, oblique
from their origin to the surface. Interzooecial space appearing
granular; under a higher power resolved into a very large num-
ber of exceedingly minute tubuli. Mesial lamina wavy in trans-
verse section, and scarcely distinguishable.

This species is only provisionally placed with Euspilopora. It
presents some points of resemblance to the Silurian genus Phyl-
lodictya, but differs too strongly in other respects to admit of
its being referred there. It probably belongs to an undescribed
genus, but being unwilling to found a new genus upon unsuffi-
cient material, I prefer to arrange the species as above till more
of the numerous Hamilton species have ben thoroughly investi-
gated.

I am indebted for the fine specimen figured to the Kev. W. H.
Barris, of Davenport, Iowa, in whose honor the specific name
is given.

Position and locality: Hamilton group, Buffalo, Iowa.

T^ENIODICTYA UMch.

(For generic diagnosis see page 393.)

TJENIODICTYA RAMULOSA Ulrich.

LXVII, Fig. 1-lb.

Zoarium a flexuous, dichotomously branching stipe, of con-
siderable height, 2 or 3 mm. in width and less than 1 mm. in
thickness, increasing in width before bifurcating, with essentially
parallel margins; attached by a small expanded base. Bifurca-
tions numerous, taking place at intervals of from 5 to 10mm.
Cell apertures arranged in longitudinal and curved diagonal
series, the longitudinal arrangement more pronounced in the center
and the curved arrangement towards the margins; about six in
2 mm. longitudinally; the oval apertures occupy the bottoms of
sloping areas; the latter are more or less confluent, sometimes

BRYOZOA. 529

hexagonal in outline, smallest in the central rows, gradual^ in-
creasing in size toward the rather wide, punctate or finely
striate margin.

Position and locality; Keokuk group: Keokuk, Iowa: Xauvoo,
Warsaw and other localities in Illinois. A common and charac-
teristic species.

var. BURLINGTONENSIS Ulrich.

PL LXVH. Fig. 2-2b.

The two specimens figured are from the Burlington limestone
at Burlington, Iowa, and agree very closely with the T. ramu-
losa, but are somewhat more robust. The cell apertures appear
to have been a little more circular and the sloping areas sur-
rounding them are never confluent so far as observed. The
material is not in condition to furnish good thin sections, so
that the internal characters could not be compared. One speci-
men is an anastomosing form and may not belong here.

T.ENIODICTYA FRONDOSA Ulrich.
PL LXVH, Fig. 5. and PL LXIX, Fig. 5-oc.

Zoarium an expanded frond, a cm. or more in height and width,
and one-half mm. or more in thickness. Surface nearly even,
marked with clusters, something more than their own diameter
(1.5 mm.) apart composed of larger sized cells. At the center of
the clusters is often found a greater or less aggregation of
small openings (mesopores?). Cell apertures in more or less reg-
ular, diagonally intersecting series, sub-circular, with moder-
ately thick interspaces, seven or eight of the average size in 2
mm., those in the clusters from one-third to one-half larger
than the others. Inter-apertural spaces ridge-like, witli the
central portion sub-angular, and when in a good state of pres-
ervation bearing minute granules. Zooecia prostrate, the ves-
tibule almost direct to the surface. In a tangential section the
space along the middle of the zooecial partitions exhibits a large

-66

530 PALEONTOLOGY OF ILLINOIS.

number of irregularly arranged minute dark spots, which only
in rare and very limited instances arrange themselves in trans-
verse lines.

The mode of growth and cell arrangement as well as the ir-
regular disposition of the intra-zooecial dots distinguish T.
frondosa from the other species of the genus.

Position and locality: Keokuk group, Keokuk, Iowa.

T^ENIODICTYA CINGULATA UMch.
PL LXVII, Fig. 3-3b.

The only specimen examined of this species is a very large,
more or less dichotomously branched stipe, three to five mm.
wide. The specimen is split through the center, showing one
side of the median lamina. Celluliferous face imbedded in the
matrix and not seen. The arrangement of the zocecia as shown
by thin sections, though similar to that of T. ramulosa, differs
in having the diagonal lines straighter and more pronounced;
diagonally about eight in two mm., longitudinally six in the
same space. The zooecia are elongate-hexagonal, the outlines
being formed by a transversely lined interspace.

In T. ramulosa, this lined interspace does not surround the
zooecia, but continues as a flexuous band between the longitudi-
nal series of cells. The present species is further distinguished
by its wider branches.

Position and locality: Keokuk group; Warsaw, 111.

T^NIODICTYA SUB RECTA Ulrich.
PI. LXVII, Fig. l-4d.

Zoarium an erect stipe, branching dichotomously; angles be-
tween branches about thirty degrees; width of branches between
2 and 3 mm., slightly less immediately after each bifurcation.
Cell apertures oval, in from twelve to sixteen longitudinal series,
appearing as though ranged between raised ridges, nine at the
margins and eleven at the center of the branch in three mm.
longitudinally; interspaces thin.

BRYOZOA. 531

The erect form of growth and acute angle of bifurcation,
thinner walls and narrower non-celluliferous margins distin-
guishes this species from T. ramulosa.

Position and locality: St. Louis group; Elizabethtown, Ky.

PTILOTRYPA Ulrich.

(For generic diagnosis see page 398.)

PTILOTRYPA OBLIQVATA Ulrich.

PL XXX, Fig. l-le.

Zoarium consisting of frondescent branches varying consider-
ably in height, width and thickness: the extremes of thickness
noticed are 1 and 6 mm, The material at hand, though abund-
ant, is not sufficient to determine the nature of the basal at-
tachment. My judgment, however, would say that the basal
portion was in Tteniodictya and not jointed as in Ptilo-
dictya. Surface smooth. Zooecial tubes almost straight in
their course from the median laminae to the surface with which
they form an angle of between 25° and 40°. Apertures lanceo-
late, rounded and with an elevated margin posteriorly, acute
and drawn out trough-like at the upper end. At irregular inter-
vals the surface presents spots where the apertures are more
than usually drawn out; they have a striated appearance and
simulate maculae. In the spaces between these spots the aper-
tures are ranged in vertical series, separated in this direction
by an interspace equal or greater than their longitudinal diame-
ter which is about 0.25 or 0.30 mm.; in the diagonal series
they approximate quite closely .the slight peristomes being sepa-
rated by only a narrow channel; measuring diagonally there
are about seven in two mm. At the upper end of each zooecium,
or in the interspace above it, is found an accessory pore. An
occasional complete diaphragm crossing at right angles is
found in most of the zooecial tubes. The walls of the tubes
have a very curious structure as shown in longitudinal and
transverse sections (fig. Id and 1 e.).

532 PALEONTOLOGY OF ILLINOIS.

This is the only species of the genus thus far described. The
obliquity of the tubes at once distinguishes it from any Ptilo-
dictyoid know to me. The associated P achy diet y a, splendens
alone sometimes approaches it in that respect.

Position and locality: Cincinnati group, Wilmington, 111.

^NTRAPORA Hall, 1881.

Trans. Albany Instit. vol. X, p. 157.
(For generic diagnosis see page 394.)

INTRAPORA COSCINIFORMIS Nicholson.

PL XLIII, llg. G, 6a.

Ptilodictyacoscini/ormis'Nich. 1875. Geol. Mag. n. s. vol. II, p. 35, PL II, fig. 2-27>.
Ptilodictyacosciniformis'NiQh. 1875. Kept. Pal. Ont. p. 80, PL II, flg. 2a, 2&.

Although differing considerably in its mode of growth from
/. puteolata Hall, the type of the genus, thin sections as figured
prove them to be congeneric. The zoarium resembles that of
Coscinium Keyserling. *

Position and locality: Hamilton group; Arkona, Canada.
It should be searched for in the Illinois and Iowa exposures of
the formation.

STiCTOPORELLAUlrich, 1882.

(Jour. Cin. Soc. Nat. Hist. vol. V, p. 152.)
(For generic diagnosis see page 394.)

STICTOPORELLA BASALTS Ulrich.

PL LXXV, flg. 5-5&.

Zoarium attached to foreign bodies by a large spreading,
thin, basal expansion, from which arise irregular inosculating

*Since writing the above, Vol. 6, Pal. N. Y., has appeared. In this work Prof. Hall
proposes a new genus, Coscinella, for a cribrose form which, if indeed It is not the
same species, is at any rate congeneric with Nicholson's P. cosciniformis. I question
very much whether Coscinella can stand as distinct from Intrapora. On the other
hand, the relationship to Coscinium is remote.

BKYOZOA. 533

bifoliate fronds, varying in width and height; thickness rarely
exceeding 2 mm., generally much less. Surface smooth, with cell
apertures sub-circular, varying but little in size, averaging 0.13
mm. in diameter, seven or eight in 2 mm., regularly arranged
in the spaces between the maculae, which usually are much the
largest over the basal expansion. Immediately surrounding the
zooecia apertures there is a narrow, slightly elevated sloping
space, which on the other side slopes again into the sub-angu-
lar mouths of a single or double series of small mesopores.
The latter are aggregated at intervals of about 3 mm. into
clusters varying much in size. Median lamina very flexuous,
with difficulty distinguished from the long prostrate basal por-
tion of the zooecial tubes. These overlap each other for a con-
siderable distance before they make an abrupt bend and proceed
direct to the surface. Walls moderately thick in the vestibular,
thin in the primitive region. Superior hemiseptum obsolete, in-
ferior, sometimes quite pronounced. Diaphragms entirely want-
ing, even in the mesopores.

Position and locality: Keokuk group; Warsaw beds, War-
saw, 111.

. STICTOPORELLA? UNDULATA Ulrich.

PI. LXIX, fig. 6-66.

The specimens upon which this species is founded are two
small, imperfect, undulating fronds, less than 2 cm. in height
and width, and about 0.5 mm. in thickness. Surface nearly
smooth, exhibiting a few inconspicuous elevations, the centers of
which are occupied by zooecia separated by slightly wider in-
terspaces than usual. Zooecia arranged in regular series vary-
ing in direction. Apertures almost circular, sub-equal, about
0.15 mm. in diameter, eight in 2 mm., with small mesopores
placed at the angles of junction. Interspaces rather thin.

The smaller and more delicate frond, and much less numerous
mesopores, distinguish this form from S. basalis of the Keokuk
group.

Position and locality: Chester group, Litchfield, Ky.

534 PALEONTOLOGY OF ILLINOIS.

FENESTELLA Lonsdale, 1839.

(Murchison's Silurian System, p. 677.)
(For generic diagnosis see page 395.)

Very much indeed might be written upon this remarkably
prolific group of Bryozoa, but, as space is limited, I must re-
frain. A few remarks however seem to be called for.

In looking over the one hundred or more described species of
Fenestella,*, we see that the original infundibuliform zoarium,
which prevailed exclusively among the species of the Cincinnati
and Clinton groups, gradually gave way in the Niagara and
Lower Helderberg deposits until in. the Upper Helderberg and
Hamilton groups it is far less common than the flabellate zoar-
ium, while in the Lower Carboniferous groups and Coal Meas-
ures the original form of growth is almost unknown. The
number of the flabellate species is also so much greater that it
is evident that the genus had not attained its most typical de-
velopment before the beginning of the Upper Helderberg. The
earliest infundibular species are really the ancestors of the whole
family, and in the Niagara and Lower Helderberg groups sev-
eral species show departures from the original simple forms
along lines of variations which did not attain full development
until well into Devonian times. Thus in F. acmea Hall, F.
thyene Hall, and other species we see the progenitors of Semi-
coscinium. Unitrypa was developed from such forms as F. qua-
drula Hall, and F. precursor Hall, while two- and three-ranged
Polyporse began early. No intermediate forms are as yet
known showing the descent of Isotrypa, of which the Niagara
F.? amhigua Hall, is already a fully developed species.

These facts are thrown out rather in the light of suggestions
to students who are desirous of working out the life history of
the family. My own investigations in this line have scarcely
begun, yet the results have already proved most gratifying and
sometimes surprising.

* Many more have been described as Fenestella that belong to Polypora, Semico-
scinium, Unitrypa and other genera of the family.

BRYOZOA. 535

FENESTELLA VERA Ulrich.

PI. XIJV. flgs. 1, la, and PI. IJV, fig. 3.

Zoarium a somewhat undulating flabellate expansion; largest
fragment seen over 6 cms. in length. Obverse with branches
rather straight, slender, ridge-shaped, bifurcating at distant in-
tervals, about 0.35 mm. in width, and twenty-four in 1 cm.
Dissepiments short, sub-carinate, varying in width from about
two-thirds to almost the width of the branches. Fenestrules
elliptical or sub-quadrangular, about 0.5 by 0,2 mm.; fourteen
in 1 cm. Carina prominent, not sharp, bearing small nodes
about twice their diameter apart, and six or seven in 2 mm.
Xorecia in two ranges. Apertures small, circular, opening ob-
liquely into the fenestrules, generally four to each fenestrule,
and twenty-three in 5 mm. On the reverse the branches are
usually zigzag, on the same level and scarcely stronger than
the dissepiments, the fenestrules have a somewhat hexagonal
shape, less marked in the older portion of the zoarium, and
form quite regular diagonal series. Surface of both branches
and dissepiments very minutely granulose.

This species was at first supposed to be identical with Front's
F. nodosn, but upon a careful comparison with his description,
I find that the measurements do not agree. The flexuous char-
acter of the branches on the reverse is perhaps the principal
peculiarity, and serves to distinguish the species from several
Devonian forms that approach it in other respects.

Position and locality: Hamilton group. Abundant at Buf-
falo, Iowa.

FENESTELLA FILISTRIATA Ulrich.

PL XLIX, fig. 2, 2a.

Zoarium a flabellate expansion, with the margins curved so
as to give to the whole a semi-funnel shape. Base slender,
solid, with root-like processes. Branches lax, rather slender,
subcarinate. 0.35 to 0.5 mm. wide, and about four in 3 mm.
Dissepiments slender, striated, varying in length. Fenestrules
subquadrangular, much longer than wide, about six in the

536 PALAEONTOLOGY OF ILLINOIS.

space of 1 cm. Carina rarely prominent, it and the sides of
the branches covered with fine longitudinal striae. Zooecia in
two ranges. Apertures circular, elevated, almost twice their
diameter apart, six or seven to a fenestrule, thirteen or four-
teen in 5 mm. On the reverse the branches are striated longi-
tudinally as on the obverse.

This species is much more delicate than the F. regalis of the
Keokuk group. F. funicula, has a stronger keel, and no striae
upon the obverse.

Position and locality: Burlington limestone, Burlington, Iowa,
and Montezuma, Pike Co., 111.

FENESTELLA BURLINGTONENSIS Ulrich.

PI. SLIX, fig. I, la.

Zoarium a foliate expansion, with strong root-like processes
extending from the sides near the base. Branches rather strong,
a little irregular, from 0.3 to 0.5 mm. wide. Dissepiments short,
rounded or subangular, depressed, from one-half to two-thirds
the width of the branches. Fenestrules irregular in shape and
size, varying from subquadrangular to narrow elliptical, aver-
aging 0.7 by 0.4 mm., with eight to ten in 1 cm. Carina
strong, moderately elevated and bearing a row of obscure
nodes. Zooecia in two ranges. Apertures circular, small, widely
separated, about seventeen in 1 cm., and from three to five to
each fenestrule. On the reverse the dissepiments are more slen-
der and fenestrules more rectangular than on the obverse. On
the branches are a few obscure nodes.

The Burlington Bryozoa are rarely good, and the examples
of this Fenestella, which I have seen are no exception to the
rule. They show perhaps too great a variation to have all
belonged to one species, yet as the state of preservation did
not admit of nice discriminations, I thought it best to unite
provisionally the forms comprised in the above description
under one name. The example of which fig. la, represents a
small portion has smaller and more crowded branches than
usual. The species is related to F. rudis of the Keokuk group,
but has smaller cell apertures and somewhat larger fenestrules.

Position and locality: Burlington limestone. Burlington, la.

BRYOZOA. 537

FEXESTELLA RTTDIS Ulrich.

PI. XLIX, flg. 3-3d.

Zoarium flabellate. usually forming but little undulated sub-
circular expansions, attaining a diameter of 7 cms. or more.
Numerous root-like strong and smooth processes strengthen the
small base from which the branches diverge. These are strong,
moderately rigid, and bifurcate at intervals varying from 5 to
15 mm. On the obverse the branches are angular, the keel
strong but not very prominent, and carries large elongated
nodes about two to each fenestrule. The elevations of the nodes
varies in different examples being very prominent in some and
scarcely perceptible in others. Age and state of preservation
largely account for the variation. The average width of the
branches also varies from 0.28 to 0.33 mm. In all the average
strength is somewhat greater near the base than at the outer
margins: their number in a given space is, however, fairly con-
stant, there being usually sixteen or seventeen in 1 cm. Fenes-
t rules elongate elliptical, twice as long as wide, with ten and
one-half in 1 cm. Dissepiments depressed, comparatively weak,
rarely half as wide as the branches. Zooecia in two alternating
ranges, eighteen in 5 mm., three to each fenestrule, with rather
large circular apertures, and slight peristome, separated by in-
terspaces of nearly the same width as their diameter, which is
about 0.12 mm. When well preserved the interspaces and dis-
sepiments are faintly striated.

Certain shallow cavities on the sides of the keel (see fig. 3b,)
may represent ooecia.

On the reverse the branches are strongly rounded, often irregu-
larly tuberculose, at other times only thickened at their junc-
tion with the dissepiments. Between the nodes the surface is
smooth or faintly striated.

This is one of the most persistent and characteristic species
of the Keokuk group, and is easily distinguished from its asso-
ciates by the robust and rather coarse aspect of its fronds. F.
burlingtonensis is nearly allied, but has larger fenestrules. The
common European F. plebeia McCoy is also closely related but
differs in a like manner.

-67

538 PALAEONTOLOGY OF ILLINOIS.

Position and locality: Keokuk limestone, Keokuk and Ben-
tonsport, Iowa, Warsaw, Nauvoo, and other localities in Illi-
nois. Also in the Warsaw beds, at Warsaw.

FENESTELLA LIMITARIS Ulrich.

PL XLIX, flg. 4, 4a.

Zoarium a convoluted foliar expansion, several cms. in width,
consisting of rather strong, rounded, subequal, and flexuous
rather than rigid branches; sixteen or seventeen in 1 cm. On
the obverse side the branches vary in width from 0.25 mm. just
above, to 0.5 just below a bifurcation, but the normal width is
fairly constant at 0.35 to 0.4 mm. Median keel obsolete, or
represented by a faint, somewhat flexuous, thread-like line,
scarcely rising above the cell-aperture margins. Zocecia in two
alternating rows, seven to two fenestrules, fifteen in 5 mm.,
with rather large and more than usually direct, circular aper-
tures, surrounded by a prominent peristome. Dissepiments de-
pressed, narrowly rounded, thin, rarely half as thick as the
branches. Fenestrules narrow, elongate sub-elliptical, indented
by the projecting cell mouths, with an average of ten in 1 cm.
On the reverse they appear wider and more regular, and may
be said to be generally oblong quadrate in outline, with the
length equal to about twice the width. Here also the branches
are rather narrowly rounded, and more or less distinctly
striated.

The very little developed median keel distinguishes this spe-
cies from F. rudis, its nearest congener. At the same time it
reminds us of species of Polypoid like P. biseriata, but as the
branches never carry more than two rows of cells it is evidently
still within the limits of Fenestella.

Position and localit}^ Keokuk group. Rare at Bentonsport
and Keokuk, Iowa.

FENESTELLA REGALIS Ulrich.

PI. L, figs. 1, la, and PL LIV. flg. 5.

Zoarium flabellate, usually forming a flat, sub-circular expan-
sion, 4 or 5 cms. in diameter. Branches very strong, rather
flexuous, bifurcating in the lower and middle portions of the

BRYOZOA. 539

expansion at intervals of 4 to 8 mm.; number of branches in
1 cm., nine or ten; average width of same, about 0.7 mm.,
just before bifurcating it is 0.8 or 0.9 mm. and just above the
division 0.5 or 0.6 mm. Dissepiments slender, less than half as
wide as the branches, rounded or sub-carinate, Fenestrules
large, of variable form, usually subangular and two or three
times longer than wide; about four or five in 1 cm. Carina
strong, rounded, bearing a row of small nodes about 0.8 mm.
apart. Zocecia in two alternating ranges, from seven to eleven
in the length of a fenestrule, and fourteen in 5 mm. Apertures
circular, about 0.16 mm. in diameter. In well preserved ex-
amples with a prominent peristome. In such the interspaces
and carina are finely striate. On the reverse the branches are
strongly convex and striated longitudinally. In tangential sec-
tions the solid substance on the sides of the branches is seen to
be traversed transversely by very fine and crowded tubuli.

The very large size of the branches and fenestrules distinguish
the species from all known to me. Indeed its branches with
their two ranges of zocecia are fully as large as those of Fenes-
tralia sancti-ludovici Prout, in which there are four rows.

Position and locality: Keokuk group. King's Mt. Tunnel,
Kentucky (On Gin. South. R. R.).

FEXESTELrLA COMPRESSA UMch.

PL L. Fig. 2a.

Zoarium a flat foliar expansion, the largest fragment seen
being over 6 cm. long. It spreads unusually slow because of
the long intervals between the bifurcations. The branches, of
which there are fourteen or fifteen in 1 cm., are rigid (especially
on the obverse), and compressed laterally, so that the zooecial
apertures look side wise rather than upward. The width of the
branches is nearly uniform, varying but little from 0.35 mm.
On the obverse they are strongly keeled. The carina carries a
series of small nodes which are nearly or quite as numerous as
the zocecia on either side. Zocecia sixteen in 5 mm. four to each
fenestrule, with small apertures and faint peristome. Dissepi-
ments slender, sub-carinate, half as wide as the branches. Fenes-
trules sub-quadrate, appearing rectangular in specimens partially

540 PALAEONTOLOGY OF ILLINOIS.

obscured by the shale; generally twice as long as wide, 8.5 in
1 cm. On the reverse the branches are rounded and distinctly
striated longitudinally.

The compressed branches, large fenestrules, small and widely
separated cell-apertures, and numerous nodes on the keel, are
the distinctive features of this species. Its frond has a more
delicate look than any of the associated forms.

Position and locality: Keokuk group. King's Mountain Tun-
nel, Ky. I have collected several fragments of this or a very
closely allied species from the Chester group at Sloan's Valley,
Ky. '

FENESTELLA COMPRESSA var. NODODORSALIS Ulrich.

PI. L, flg. 2.

This name is proposed, provisionally, for a form of which I
have seen only one example. This is over 8 cm. in length by 4
cm. in its greatest width. It adheres tightly to a slab of lime-
stone from King's Mountain, with the reverse, which is finely
preserved, exposed. As it agrees fairly well in the strength of
its branches, form and size of its fenestrules, with F. compressa,
I at first supposed that it represented the reverse of that species.
Having occasion to prepare some thin sections of the type speci-
mens of F. compressa, I was surprised at seeing no indications
of a tuberculated reverse. This discovery led to an examina-
tion of all the specimens I had referred to the species. The
result was that the reverse of all the specimens, excepting the
one in question, was found to be simply rounded and even. A
careful comparison shows that beside the strong and irregular
nodes, there are also slight differences in the measurements.
Thus, while F. compressa has fourteen or fifteen branches and
8.5 fenestrules in 1 cm., this specimen has twelve or thirteen
branches, and 7.5 to 8 fenestrules to that space. Under these
circumstances it seenls best to refer to it as above.

FENESTELLA MTJLTISPINOSA Ulrich.

PL L, Figs. 3-3e.

Zoarium a strongly undulating flabellate expansion. The
largest example seen (it is nearly perfect) measures in different

BRYOZOA. 541

directions from the base from 5 to 7 cm. Strong root-like
appendages spring from the free margins and from both fa
of the basal portion. Branches rigid, except near the base,
where frequent bifurcations make them appear flexuous. They
are also slender, from 0.3 to 0.4 mm. wide, with twenty to
twenty-one in 1 cm., but being well knit together the whole
frond appears comparatively strong. On the obverse the keel
is pronounced but never sharp, and bears, on an average, three
small nodes to the fenestrule. Zooecia in two ranges. Apertures
small, sub-oval or slit-like, seemingly situated in a groove at
the base of the keel, with the outer margin prominent, some-
times appearing almost spine-like; twenty-one in 5 mm., two or
three in each fenestrule. Certain saucer shaped depressions
which occasionally take the place of one of the zooecia, may be
of the nature of ooecia. Dissepiments half or less than half as
wide as the branches, scarcely depressed, carinate. Fenestrules
(beyond the basal parts) regular, elliptical or sub-quadrate,
fourteen or fifteen in 1 cm. On the reverse near the outer mar-
gin, the branches are straight, and covered with granose longi-
tudinal striae; the dissepiments half as strong, and the fenes-
trules sub-quadrate, with the length nearly twice the width.
Toward the base the branches and dissepiments, the latter par-
ticularly, are much thickened, so that the fenestrules gradually
become round -oval. The granules are also larger and no longer
arranged in longitudinal lines.

This fine species may be compared with F. compressa and
F. serratula. The former differs in having much larger fenes-
trules and in wanting granules on the reverse. The latter in
being more delicate and smaller in every feature.

Position and locality: Keokuk group. Bentonsport and
Keokuk, Iowa, and King's Mountain, Ky.

FENESTELLA TRISERIALIS Ulrich.

PI. L, figs. 4. 4a.

Zoarium a foliaceous expansion. Branches rigid, of moderate
strength, 0.4 to 0.45 mm. wide, seventeen or eighteen in 1 cm.;
rather flat on the poriferous side, which alone has been seen.

542 PALEONTOLOGY OF ILLINOIS.

Dissepiments short, depressed, slender, less than half the width
of the branches. Fenestrules 12.5 in 1 cm., each about 0.6 mm.
long and 0.25 mm. wide; with the sides indented. Carina very
small, with a row of closely set small nodes, and on each side a
continuous or interrupted fine line. Zooecia in two ranges.
Apertures circular, with well .developed peristome, comparatively
large, closely arranged, their diameter or less apart, nineteen
or twenty in 5 mm., and regularly three to each fenestrule. A
very perfect fragment, obtained since the plates were litho-
graphed, shows a peculiar feature not noticed at that time. At
the same time it explains the small spots which are shown in
sections between the cells. In this specimen a long tubular
spine extends from the interspace between the apertures ob-
liquely outward and upward. Being very delicate, these spines
would readily give way to attrition, but, since I know of its
existence, I can detect its base in the other specimens.

Perfect examples of this interesting species could not be con-
founded with any other known. In its ordinary state of pre-
servation it resembles F. multispmosa, but differs in having
longer fenestrules, larger branches and zooecia apertures, and
less angular obverse side to the branches. The last character
and the large cell apertures distinguish it from F. compressa,.
That species also has larger fenestrules.

Position and locality: Keokuk group. Rare at King's Moun-
tain, Ky.

FENESTELLA FUNICULA Ulrich.

PL LI, fig. 6.

Zoarium an irregular foliar expansion. Branches fourteen or
fifteen in 1 cm., comparatively slender, about 0.4 mm. wide, at
times a little flexuous, approaching and receding from one
another without regularity. Bifurcations at variable though
generally rather distant intervals. Dissepiments of unequal
length; their width a little more or less than one-half that of
the branches. Fenestrules variable in size and shape, from three
to four or five times as long as wide, with about five in 10

BRTOZOA. 543

mm. Carina strong, cord-like, carrying strong nodes about 0.7
mm. apart. Zo<ecia in two alternating ranges. Apertures oc-
cupying a groove at the base of the carina, thirteen in 5 mm.,
usually sub-circular, with only the outer margin strongly ele-
vated; often they appear slit-like, an appearance probably due
to compression; from four to six or even more between suc-
ceeding dissepiments. Reverse not seen.

This species is less robust and more irregular than F. regalis.
F. filistriata of the Burlington limestone, is more delicate and
without the cord-like keel.

Position and locality: Keokuk group. Rare at Keokuk, Iowa.

FEXESTELLA CINGVLATA Ulrich.

PI. EH, flgs. l-ld.

Zoarium a large and strong, flat, foliar expansion, the larg-
est fragments at hand indicating a diameter of at least 8 em.
Branches strong, equal, about 0.5 mm. wide, rigid, bifurcating
at long intervals: fifteen in 1 cm. Dissepiments strong, gener-
ally two thirds as wide as the branches, usually elevated node-
like, a peculiarity particularly noticeable on weathered exam-
ples, giving them a very characteristic rough appearance. Fen-
estrules narrow, indented by the cell margins, about 0.8 mm.
in length, and 0.15 to 0.25 mm. in width, eight or eight and
one-half in 1 cm. Cariiia not well developed but bearing con-
spicuous nodes. Zoo?cia in two alternating ranges. Apertures
circular. 0.15 mm. in diameter, with strong peristome, about
seven to two fenest rules and fifteen to sixteen in 5 mm. The
opercular covers to the apertures are frequently preserved.
Tangential sections taken close to the surface show the exist-
ence of a ring of exceedingly minute vertical pores around the
zooecia aperture. Under a high power these appear on the sur-
face of the peristome as minute granules. On the reverse the
branches are simply convex and narrower, the fenestrules larger
and more regular in size and shape, while the dissepiments are
about as wide as the branches, and on the same plane with
them. Their surface is crowded with minute granules, which
only on very young examples are arranged in longitudinal

544 PALEONTOLOGY OF ILLINOIS.

series. The specimen of which fig. la represents a portion,
differs from all the others in having only thirteen or four-
teen branches and seven fenestrules in 1 cm. In other respects
it seems to agree very well with the typical examples above de-
scribed.

This is the only species of the genus in which I have noticed
anything like the ring of minute tubes around the zooecial aper-
tures. Perhaps it is a similar feature that Mr. Shrubsole figures
for his Wenlock species, F. reteporata. In its proportions F.
cingulata approaches F. rudis, but there are really so many
differences between them that when once determined, even poorly
preserved fragments are easily separated.

Position and locality: Keokuk group. Nauvoo, 111., and
Keokuk, Iowa.

FENESTELLA SERRATULA Ulrich.

PI. L, flg. 5-5c.

This beautiful little species is known from the Keokuk, St. Louis
and Chester groups and from the Warsaw beds. In each of these
geological divisions the species has undergone some slight but
recognizable changes, making it possible to distinguish them.
Still they all agree so closely in their proportions and general
appearance that I cannot for a moment question their specific
identity.

Zoarium a foliar expansion, from 3 to 5 cms. in diameter.
Branches rigid, small, 0.25 mm. wide, twenty-five or twenty-six
in 1 cm., with a comparatively strong mesial carina, carrying
small nodes, which give it on a side view the serrated appear-
ance that has suggested the name. Nodes and zooecia twenty-
four to twenty-six in 5 mm., and three to each fenestrule. Aper-
tures very small, 0.07 mm. in diameter with a prominent
peristome when perfect. Dissepiments thin, not more than
half as wide as the branches, depressed and carinate on the ob-
verse side. Fenestrules na.rrow elliptical, seventeen to nineteen
in one cm. Reverse of branches granulo-striate or nearly smooth
(?), with an occasional long, barbed, spine-like appendage.

BRYOZOA. 545

The Keokuk form is the smallest. Its branches bifurcate much
more frequently than usual causing the frond to expand so
rapidly that its edges meet or even overlap each other.

In the Warsaw beds specimens, which do not bifurcute as
rapidly as in the Keokuk form, the reverse of the branches
is finely granulo-striate when well preserved, and the fenestrules
number eighteen or nineteen in 1 cm.; with twenty-five or twen-
ty-six cell apertures in 5 mm.

In the Chester examples, which are rather large, strongly un-
dulating expansions, the granules have not been observed on
the longitudinal striae, and the fenestrules number seventeen or
eighteen in 1 cm.; the cell apertures twenty-four or twenty-five
in 5 mm.

The St. Louis limestone form is intermediate in its characters
between the Warsaw specimens on the one hand and those of
the Chester on the other.

Though closely allied to F. multispinosa, its smaller propor-
tions readily distinguishes it. In that species there are twenty-
one zocecia in 5 mm., while F. serrata has from twenty-four to
twenty-six in that distance.

Position and locality: Keokuk group. Nauvoo, 111.; Warsaw
beds, Warsaw and Monroe Co., 111.; St. Louis limestone locali-
ties in Caldwell, Lyon and Crittenden counties, Ky., occurring
in the shaly and cherty beds of the group; Chester group,
Sloan's Valley, Ky., where it is abundant.

FENESTELLA EXIGUA Ulrich.

PI. LI, figs. 1-la.

Zoarium a delicate foliar expansion. Branches slender, slightly
flexuous, laterally compressed, of uniform width, about 0.27
mm. wide, with twenty or twenty-one in 1 cm. Dissepiments
short, hour-glass shaped, one-half as thick as the branches.
Fenestrules quite regular in size and shape, elliptical, about 0.6
by 0.2 mm., and thirteen to fourteen in 1 cm. Carina strong,
elevated, with nodes about 0.4 mm. apart. Zocecia in two
ranges. Apertures occupying a slight groove at the base
of the carina, circular, rather large, their diameter or less apart,

—68

546 PALEONTOLOGY OF ILLINOIS.

twenty-two or twenty-three in 5 mm., so arranged that several
times four to once three come in the space of a fenestrule. Or-
dinarily the peristome is wanting or faint, but on perfectly pre-
served portions it is remarkably prominent. On the reverse the
branches and dissepiments are more nearly equal than on the
obverse, their surface is strongly convex and smooth excepting
opposite the ends of the dissepiments where a strong node is
developed on the branch, The fenestrules are regularly ellip-
tical.

In its proportions this species is larger than F. serratulu and
much smaller than F. compressa.

Position and locality: Warsaw beds. Monroe Co., 111.

FENESTELLA TENAX Ulrich.

PI. LI. figs. 2— 2e.

Zoarium a very delicate but large foliar expansion, the largest
fragment seen being 8 cm. high by 5 cm. wide. At the base
and along the free lateral margins ther6 are those peculiar
barbed spine-like appendages. Branches slender, bifurcating at
distant intervals, from 0.2 to 0.3 mm. (the latter just before
bifurcation) wide. Dissepiments thin, rounded, one-fourth to
one-third as large as the branches. Fenestrules long oval,
0.3 mm. long and 0.12 wide, indented once on each side when
perfect. Carina strong, elevated, with declining sides, bearing
traces of numerous small spines. Zooecia in two ranges, with
pustulose mouths. Apertures circular, small, more than their
own diameter apart, usually situated, one opposite the end of
each dissepiment and one opposite the middle of each fenes-
trule. On the reverse the branches show obscure striations and
granulations, the dissepiments are thin, on a plane with the
branches or a little depressed below them, wider and more rect-
angular than on the obverse.

Warsaw beds examples: branches in 1 cm. 28 to 30; fenestrules
in 1 cm. 29 or 30; zocecia in 5 mm. 28 or 29. Average Chester
group example: .branches in 1 cm. 28 to 30; fenestrules in 1 cm.
28 or 29; zooeciainSmm. 27 or 28. Variety from the Chester group:
branches in 1 cm. 28 or 29; fenestrules in 1 cm. 23; zocecia in 5

BRYOZOA. 547

mm. 24 or 25. The measurements of the branches and fenes-
trules .in the last are taken from a large and fine example, that
shows only the reverse. Fig. 2e, represents a part of one of its
branches, and shows the relatively larger fenestrules. The cells
were counted on a similar but more typical example.

In many respects this species resembles F. serratula. Both
are abundant and almost constantly associated, showing that
they are not local varities of one species. F. teuax has smaller
and more numerous branches, as well as smaller fenestrules.
Lying side by side, as it often happens, it needs but a glance
to discriminate between them. Small fragments of both species
resemble the fronds of associated species of Archimedes (particular-
ly A. proutana and A. distans,) and it is only by becoming familiar
with them through practice that they can be distinguished satis-
factorily.

Position and locality: Warsaw beds, Warsaw, and Monroe
Co., 111. Chester group, Chester and Kaskaskia, 111., and Sloan's
Valley, Ky.

FENESTELLA CESTRIENSIS Ulrich.

PL LI, flgs. 5-5b.

Zoarium an irregular foliar expansion, 5 or more cms. in
length. Branches slender, rather rigid, 0.3 to 0.4 mm. wide,
bifurcating at distant though variable intervals, seventeen to
twenty in 1 cm., the average, however, being about nineteen.
The two faces of the obverse side are rather flat and slope
downward rapidly from the sharp cariiia. Dissepiments short,
ridge-shaped, about one-half as wide as the branches. Fenes-
trules averaging ten in 1cm., the extremes noticed being one
more or less, varying from long sub-rectangular to long sub-
oval, 0.8 by 0.3 mm. Carina scarcely elevated, when perfect,
bearing a row of short spines, usually four in the length of a
fenestrule. Zooecia in two alternating ranges, twenty-one or
twenty-two in 5 mm., four or five to each fenestrule. On the
reverse the branches are narrowly rounded, distinctly striated
in the younger or marginal portions of the expansion, with

548 PALAEONTOLOGY OF ILLINOIS.

irregularly distributed nodes and no striations toward the basal
or older parts. The fenestrules are more nearly rectangular
than Jon the obverse.

This graceful species is one of the most characteristic Bryo-
zoa of the Chester group. Although in no case very abundant
it occurs at all the typical localities. In its measurements the
the species agrees quite closely with F. flexuosa,, yet the two are
not likely to be confounded.

Position and locality: Chester group, Chester, Kaskaskia,
near Anna, and other localities in the State of Illinois. Also
at Sloan's Valley, and Litchfield, Ky.

FENESTELLA FLEXUOSA Ulrich.

PI. LI, figs. 4— 4c.

Zoarium a somewhat undulating foliaceous expansion that
probably did not exceed 5 or 6 cms. in diameter. Branches
slender, 0.3 to 0.35 mm. wide, rather irregularly flexuous, alter-
nately bending toward and away from one another, eighteen to
twenty in 1 cm. Dissepiments very short, connecting the
branches where they approach each other nearest, their width
about equal to that of the branches. Fenestrules long-oval,
more or less pointed at the ends, somewhat variable as to size,
about 0.8 by 0.2 mm., and nine or nine and one-half in 1 cm.
Carina rather strong, moderately elevated, with generallv three
strong nodes or spines to the fenestrule. Zocecia in two ranges
about twenty-two in 5 mm. Apertures circular, their diameter
or less apart, four or five to each fenestrule, with well developed
peristome. On the reverse the branches are very finely granu-
lo-striate or smooth, narrowly rounded or carinated, and on
account of their zigzag direction, usually apper to inosculate.
The fenestrules are a little longer than on the opposite side,
elliptical, but somewhat variable both in shape and size.

This is a well marked form, and ought never to be confounded
with any other Carboniferous species known.

Position and locality: Chester group. Not uncommon at
Sloan's Valley, Ky.,? Chester, 111.

BRYOZOA. 549

FEXESTELLA ELEVATIPORA Ulrich.

PI. LI, Figs. 3-3a.

Zoariurn a flat foliar expansion, of which only small frag-
ments have been seen. Branches rigid, closely approximated,
0.25 to 0.3 mm. in width, twenty-five or twenty-six in 1 cm.
Dissepiments short, slender, so much depressed that they are
easily overlooked on examples adhering to the rock or shale.
Fenestrules small, irregular in shape, about two and one-half
times as long as wide, with about twenty-four in 1 cm. Obverse
side of branches comparatively flat. Carina small, thread-like.
Zooecia in two ranges, twenty-six in 5 mm. Apertures circular,
directed outward, pustuloid, the peristome being very promi-
nent; generally two to each fenestrule. On the reverse the
branches are rounded and occupied by from three to five thread-
like longitudinal striae, the fenestrules longer than on the ob-
verse, and subquadrate in form.

The more strongly striated reverse, the less convex and some-
what wider obverse face of the branches, and their crowded ap-
pearance separate this species from its close relation, F. tenax.
Other differences will be noticed on comparison.

Position and locality: Chester group, Chester, 111., and Crit-
tenden Co., Ky.

FENESTELLA DELICATTJLA Ulrich.

PI. LTI.Fig.2.

Zoarium a very delicate, rapidly expanding, foliar expansion,
not known to exceed 2 cm. in diameter. Branches very slender,
about five in 5 mm., scarcely 0.3 mm. in width; strongly convex
and finely granulose on the reverse, and ridge like on the ob-
verse. Dissepiments long and very slender. Fenestrules sub-
quadrangular, about 1.5 by 0.7 mm., and six or seven in 1 cm.
Carina comparatively strong, rounded, with an occasional very
small node. Zooecia in two alternating ranges, about sixteen in
5 mm. Apertures circular, small, and widely separated; five or
six to the fenestrule; peristomes prominent, especially upon the
outer side where they encroach upon the fenestrules.

550 PAL^ONTOLOGl OF ILLINOIS.

The specimens upon which this species is founded are very
fragmentary, but as they are in a fine state of preservation and
quite distinct from all the carboniferous species known to me, I
have ventured to describe them as new.

Position and locality: Base of Coal Measures, Seville, 111.

FENESTELLA MODEST A Ulrich.

PI. LII, Fig. 3-3b.

Zoarium a small fan-shaped expansion; the largest specimen
seen is 17 mm. in breadth, and somewhat less in height.
Branches bifurcating frequently, slender, keeled, flexuous, 0.2
mm. in width, five or six in 3 mm., covered with fine longitudi-
nal striations which continue from a branch across the dissepi-
ments to the next branch. Dissepiments slender, rounded.
Fenestrules subquadrangular, somewhat variable in size, about
0.7 by 0.3 mm., and six or seven in 5 mm. Carina rounded,
not strongly elevated, with small nodes about 0.4 mm. apart.
Zocecia in two ranges, twenty or twenty-one in 5 mm. Aper-
tures circular, surrounded by a thin peristome, almost twice
their diameter apart, arranged several times three to once four
in the space of a fenestrule. On the reverse the branches are
covered with exceedingly fine, granulose, interrupted striations.

The specimens from Knox Co., 111., occur as natural molds
in a soft, fine grained, siliceous rock. The gutta-percha impres-
sions which were prepared from them are, as usual, exceedingly
perfect, showing clearly the minutest details of external struc-
ture and ornamentation. On the Seville examples the cell
mouths, and, apparently, the keel as well, are a little more
prominent than in those from Knox Co.

When compared with carboniferous species the distinctive
features are the rapid expansion and small size of the frond, the
comparatively large fenestrules, and the widely separated cell
apertures. F. delicatula has larger fenestrules and five or six
apertures instead of three or four to each. F. inimica is a more
compact form and has stronger and rigid branches.

Position and locality: Coal Measures, Knox County and
Seville, 111.

BRYOZOA. 551

FEXESTELLA PERMINUTA Ulrich.

PL LH. Fig. 4-lb.

Zoarium an exceedingly delicate small expansion, growing
from a spreading foot stalk into a remote resemblance to Ptilo-
pora. From both sides of the central stem two branches spring
out at a rather acute angle. These are very slender, bifurcate
at short intervals, and are 0.15 mm. in width. Dissepiments
long, extremely slender, at first about equal in number to the
bifurcations. Fenestrules of variable shape, averaging 0.5 bv
0.3 mm. Carina very little developed, almost obsolete. Zooecia
apertures in two alternating rows, circular, prominent, project-
ing decidedly beyond the margin of the branch, more than twice
their diameter apart, with twelve in 3 mm. On the reverse the
branches are finely striated.

The extreme delicacy of the zoariurn, in which the species is
not equalled by any other known to me, and the projecting
cell-apertures, are regarded as the principal peculiarities.

Position and locality: Coal Measures, Seville, 111.

>

FENESTELLA WORTHENI Ulrich.

PI. LH, Fig. 5-5a.

Zoarium a small, delicate, fan-shaped expansion. Branches
comparatively strong, about twelve in 5 mm., each 0.25 mm.
in width. Dissepiments about half as wide as the branches,
rounded and widening considerably at the ends. Fenestrules
sub-quadrangular, indented a little on each side, about 0.3 by
0.2 mm. and twelve in 5 mm. Carina very strong, sub-cylindri-
cal or thread-like, about half as thick as the entire branch.
Along the middle of the carina there is a row of small nodes,
(their apical opening is better preserved than usual), distant
from each other about 0.15 mm. Zooecia in two ranges, twenty-
four in 1 cm. Apertures small, circular, almost three times
their diameter apart, situated one at the end of each dissepi-
ment and one opposite the middle of each fenestrule. Peristome
indistinct. Reverse not seen.

552 PALEONTOLOGY OF ILLINOIS.

This interesting little species resembles F. tenax in many re-
spects, yet has even a more delicate zoarium, and the cells more
regularly arranged, while the strong cord-like keel gives it a
peculiar appearance quite foreign to that one.

Position and locality: Base of Coal Measures, Seville, 111.

FENESTELLA SEVILLENSIS Ulrich.

PL LII, Figs. 6-6a.

Zoarium a foliaceous expansion. Branches straight rather
slender, rounded, 0.3 mm. wide, six in 3 mm. Dissepiments
thin, about one-third as wide as the branches. Fenestrules quite
regularly sub-quadrangular, 0.5 by 0.2 mm., eight in 5 mm.,
slightly indented at the middle by the encroaching zocecia
mouths. Carina obsolete, replaced by a fine sharply impressed
line, bordered on each side by an intermittently stronger and
fainter raised line. One or two thinner lines usually mark the
longitudinal interspace between the cell apertures. Zocecia in
two ranges, sixteen or seventeen in 5 mm. Apertures compara-
tively large, circular, scarcely twice their diameter apart, usually
situated one at each end of each dissepiment and one at a point
midway between (i. e., about two to each fenestrule). On the
reverse the branches are rounded and have five or six fine
parallel striae. The fenestrules here are nearly rectangular.

The presence of an impressed line instead of a raised keel, and
the interrupted striae are regarded as the distinctive features.

Position and locality: Base of Coal Measures, Seville, 111.

FENESTELLA MIMICA Ulrich.

PI. LII, figs. 7, 7a.

Zoarium a small foliar expansion. Branches rather slender,
rigid, about 0.25 mm. in width, and seven in 3 mm. Dissepi-
ments short, about one-third as wide as the branches. Fene-
strules sub-quadrangular, strongly concave at the sides, 0.35
by 0.2 mm. and seven in 3 mm. Carina a very fine and but
little projecting line, bearing a row of small spines about 0.12
mm. apart. Zocecia in two ranges, twenty-four in 5 mm. Aper-
tures large, circular, with well developed peristome, slightly
more than their diameter apart, generally two to each fenes-

BKYOZOA. 553

trule, so arranged that one is opposite each dissepiment and
one between. Opercular covers the same as those of the F.
sevillensis, F. wortheni, F. rudis, and many other species.

This species is closely related to F. tenax, of the Warsaw and
Chester beds, but is more delicate, has larger cell apertures and
fenestrules and a smaller number of branches in a given space.
F. sevillensis is larger, has longer fenestrules, fewer cells, and
an impressed mesial line instead of a keel. F. wortheni differs
in its remarkably developed keel.

Position and locality: Coal Measures. Seville, 111.

FENESTELLA CONRADI Ulrich.

1 PL LH, figs. 8, 8a.

Zoarium a strongly undulated foliar expansion, several cm.
in length. Branches strong, appearing very rough on their ob-
verse side, about 0.4 mm. wide, with twenty-one or twenty-two
in 1 cm. Dissepiments very short and broad. Fenestrules nar-
row, sub-elliptical, averaging 0.33 by 0.15 mm., sixteen or sev-
enteen in one cm., arranged in diagonally intersecting series.
Carina itself not much elevated, but the rather closely arranged
compressed spines which it bears are very strong and exception-
ally prominent when perfect. Their bases are often in contact
when they form a sort of rough crest. Zooecia in two ranges.
Apertures circular, with slight peristome, arranged in a not
very straight line, so that there are several times three to once
two in the space of a fenestrule; twenty-three in 5 mm. On
the reverse the branches and dissepiments are rounded, on the
same plane and about equally thick, the former being thinner
than on the obverse side. The fenestrules are almost perfectly
circular. A small node, perforated at its summit, often occupies
then center of the branch at a point midway between four
ad j acent fenestrules .

The circular fenestrules and other features of the reverse, and
the strong spines on the keel, (they are more conspicuous than
in fig. 8,) are relied upon in separating this species. The ob-
verse brings F. rudis to mind, but that species is so much
more robust that comparisons are unnecessary.

—69

554 PALAEONTOLOGY OF ILLINOIS.

The name is given in honor of the discoverer, Prof. A. H.
Conrad, of Shenandoah, Iowa.

Position and locality: Upper Coal Measures. Seven miles
north of Red Oak, Iowa.

FENESTELLA IN^QUALIS Ulrich:

PL LH, figs. 9, 9a.

Zoarium a strong, irregular, foliar expansion. Branches
rather strong, not very straight, sixteen to eighteen in 1 cm.;
variable in size on the reverse, where their width varies between
0.8 and 0.5 mm.; more equal on the obverse face, where their
average width is about 0.4 mm. Dissepiments short, narrowly
rounded, of variable thickness, generally less than half the
width of the branches. Fenestrules sub-quadrangular or ellipti-
cal, unequal, averaging 0.8 by 0.8 mm., and nine in 1 cm.
Carina strong but not much elevated, at the summit with a
series of closely arranged small nodes, about ten in 1 mm.
Zooecia in two ranges, seventeen or eighteen in 5 mm. Aper-
tures small, circular, surrounded by an abruptly elevated peri-
stome which projects a little beyond the margin of the branch;
a fraction less than four to a fenestrule. On the reverse the
branches are marked with longitudinal, parallel, granulose
striae. The granules are distinct, and so closely arranged that
their bases are in contact. When a little worn they disappear,
and the surface is thon either smooth or simply striated. The
fenestrules have about the same form and are but little, if any,
larger than on the obverse side.

None of the Coal Measure species known to me are as large
as this one, nor is any one of them sufficiently like it to re-
quire close comparisons. Of Lower Carboniferous species, F.
cestriensis and F. compressa are related, but not very closely.

Position and locality: Upper Coal Measures. Ball's Mill, San-
gamon Co., 111.

BRYOZOA. 555

SEMICOSCIXIUM Prout, 1859.

(Trans. St. Louis Acad. Sci. vol. 1, p. 443.)
(For generic diagnosis see page 395.)

On account of certain very unfortunate errors in Prout's
original diagnosis of this genus, the name has not become cur-
rent. His type specimen was, however, almost beyond question,
a fragment of a large and easily recognized species which is
common at the Falls of the Ohio. He mistook the obverse for
the reverse side, and described the thin membrane which is often
drawn over the summits of the high carinae, as a longitudinally
lined sole. The spaces between the branches and this membrane
is filled with vesicular tissue. This he noticed and described,
together with the true zooecia, which he called "tortuous tubes,"
as a part of the "sole." The cells, he supposed, originated in
the tortuous tubes and opened into the fenestrules. In short,
his conception of S. rhomboideum was altogether incorrect.

The genus as now defined, departs from Fenestella in having
the keel very much higher and expanded at the summit, and
the branches zigzag on the reverse. The zoarium is always
infundibuliform. with the inner side non-celluliferous.

Species of this genus can be recognized in the Niagara group,
but it is not until we reach the Upper Helderberg rocks that
they assume their most marked peculiarities and become abund-
ant. Here we find nineteen species, the majority of which have
been described by Prof. Hall under Fenestella. Seven more
species are described by that author from the Hamilton group.
Above this horizon the genus is not known.

SEMICOSCTVIUM PLAXODORSATUM Ulrich.

PI. XLIV, figs. 3-36.

Zoarium infundibuliform above the abruptly contracted base,
with the free margins nearly flat, and somewhat undulated.
Outer surface celluliferous, strongly ridged. Branches rather
slender, sixteen or seventeen in 1 cm., 0.3 mm. wide just before
a bifurcation, increasing gradually to 0.5 or 0.0 mm. Dissepi-
ments very short, depressed, wider than the branches. Fene-

556 PALAEONTOLOGY OF ILLINOIS:

strules very small, 0.25 by 1.2 mm., sub-oval, eleven or twelve
in 1 cm. Carina about 0.4 mm. in height, thin at first, with
the summit abruptly expanded and angular along the middle.
The sides are wavy, the undulations corresponding closely both in
number and position, with the zooecia apertures beneath them.
Zooecia in two ranges, one on each side of the median keel.
Apertures circular, opening directly upward, about 0.1 mm. in
diameter, as much or a little more apart, eighteen in 5 mm.;
with well developed peristome. On the reverse the fenestrules
vary from quite regularly circular to broad oval, are 0.3 or
0.4 mm. in diameter, and much farther apart longitudinally
than transversely. Surface of branches and dissepiments, when
well preserved, with numerous small nodes, and varying between
slightly convex or flat and appreciably concave. In the last
case the fenestrules are encircled by an elevated rim.

This species is smaller in its proportions than either Fene-
stella semirotunda or F. permarginata Hall, from the same
locality. Both of those species, which clearly belong to Semi-
coscinium, also have twenty cells to 5 mm., while in this there
are only eighteen in that distance. Right here it may be well
to remark that Hall's figures of the two species mentioned
(Pal. N. Y. Yol. VI, PI. 49) appear to be somewhat mixed.

Position and locality: Upper Helderberg group; Falls of the
Ohio river.

SEMICOSCINIUM RHOMBICUM Ulrich.

PI. XLIV, figs. 4-4a, and PI. LIV.fig. 8.

Zoarium infundibuliform, large, undulated. Celluliferous face
with the branches rather slender, more or less flexuous, alter-
nately approaching and receding from each other, bifurcating
at long intervals, very gradually increasing from 0.3 to 0.5
mm. between the bifurcations, seventeen or eighteen to 1 cm.
Dissepiments very short, the branches appearing almost to in-
osculate, their width equal to or greater than the length of the
fenestrule, varying from 0.6 to 1.0 mm. Fenestrules oval,
rather unequal, but averaging about 0.6 by 0.2 mm., eight in
1 cm.; regularly alternating in the adjoining longitudinal series.

BRYOZOA. 557

Carina strongly elevated, flexuous, but little thickened at the
summit, frail, easily broken or worn away. Zooecia in two
ranges separated by a keel. Apertures circular, 0.09 mm. in
diameter, their diameter or more apart, twenty-two in 5 mm.
On the sides of the branches, but always opposite a dissepi-
ment, are a number of large, irregularly distributed, shallow,
thin rimmed sub-circular cells, about 0.3 in diameter, extending
from the keel nearly across the dissepiment. Their number is
variable but the average is about as shown in the figure. Simi-
lar structures are known to be possessed by several species of
Fenestella, and unless they represent ooecia, their nature is not
understood. As usual in species of this genus, near the base the
carinse are covered by a thin calcareous membrane, and the
space under this and between the branches, is filled with loosely
woven vesicular tissue. On the reverse the fenestrules are oval
or sub-rhomboidal and arranged in regular diagonally inter-
secting series, eleven or twelve in 1 cm. The branches are thin-
ner than the width of the fenestrule, carinate when wTell pre-
served, zigzag, and united by inosculation so as to form regular
rhombs. The point of junction or intersection is more or less
prominent.

This fine species is distinguished by the flexuous branches,
and the large cells (? ooecia). S. rhomboideum Prout, has fif-
teen fenestrules where this has only twelve. They are besides
not so regularly rhombic.
'Position and locality: Hamilton group; Buffalo, Iowa.

FENESTRAPORA Hall, 1887, (1885?)

(Pal. N, Y. Vol. XVI, p. XXH.)
(For generic diagnosis see page 395.)

At first I was not inclined to admit this genus, but the sub-
sequent finding of the dimorphic pores in three distinct species
has convinced me of its claim to recognition. As regards the
nature of these pores, I can only suggest a comparison with
the "avicularian" cells of the Chilostomata.

558 PALAEONTOLOGY OF ILLINOIS.

FENESTRAPORA OCCIDENTALIS Ulrich.

PI. XLIV, tigs. 2— 2a, and PI. LIV, flgs. 7-7e.

Zoarium infundibuliform, expanding rapidly, almost salver-
shaped, but rounding gradually from the short stem into the
horizontal portion. The free margins are flat or somewhat un-
dulated. On the obverse or outer side, the branches appeal-
rigid, moderately strong, and increase in width from 0.3 to 0.5
mm.; fourteen or fifteen in 1 cm. Dissepiments short, depressed,
as wide or wider than the branches. Fenestrules rather regu-
larly oval, averaging 0.7 by 0.38 mm. with eight in 1 cm. Car-
ina about 0.4 mm. high, expanded at the summit, subangular
or rounded above; both sides present a series of large pits or
cells, separated by unequal intervals, but the average may be
placed at two in the space of a mm. One of the cells also oc-
curs on the top of the carina just beneath the bifurcations.
Zocecia in two ranges, one on each side of the median keel.
Apertures circular, nearly direct, about 0.09 mm. in diameter,
about twice their diameter apart, twenty in 5 mm.; and with
a faintly elevated peristome.

On the reverse or inner side the fenestrules are broad oval,
being wider then on the opposite face; rather irregularly ar-
ranged, varying from quincuncial to directly opposite. In the
first order, which apparently prevails mainly near the center,
the branches are zigzag, and somewhat depressed below the
much stronger longitudinal interspaces that represent the dis-
sepiments. In the other arrangement the branches are nearly
or quite straight, and again much thinner than the rounded
dissepiments, which continue across them obliquely or at right
angles. The fenestrules are always wider than the branches.
Large cells, of the same nature as those in the carinae, with an
average diameter of 0.14 mm., and direct or oblique apertures,
are distributed over the surface of the branches and dissepi-
ments. Their number is about equal to that of the fenestrules.

The internal structure is fully illustrated on PI. LIV. When
compared with F. biperforata Hall, from the same horizon
in New York, we find that that species is more delicate, has
the fenestrules smaller, the carina less pronounced, and the di-

BRYOZOA. 559

morphic pores on the summit instead of the sides, and much
more numerous on the reverse. The branches are also more
rigid. The form described by me as Semicoscinium infraporosum
(Contr. Am. Pal. Vol. I, PI. I, 1886) has aU the characters of
Fenestrapora. It is from the Upper Helderberg group, and
differs from the two Hamilton species in its smaller size, strongly
undulated frond, flattened and comparatively strong reverse
aspect of its branches, and other points of minor importance.
Position and locality: Hamilton group; Buffalo, Iowa.

HEMITRYPA Phillips, 1841.

CPaL Foss. of Cornwall, Devon. & Westsomerset, p. 27.)
(For generic diagnosis see page 396.)

For further discussions see chapter on classification, under the
section treating of the FENESTELLID.E (page 349). Of the four-
teen or more species known, one is from the Clinton, two from
the Lower Helderberg. one or more from the Hamilton, four
from the Keokuk and one or more from the Warsaw and St.
Louis limestone.

HEMITRYPA TENERA Dlrich.

PL XLIV, fig. 7— 7a, and PL LIT, fig. 10— lOc.

Zoarium infundibuliform, only known from fragments. The
obverse is a very delicate net-work in which the principal and
secondary bars are indistinguishable, being equal in width and
both zigzag: connected by lateral bars or scale? of the same
width, they form equal hexagonal interstices, arranged in very
regular vertical and diagonally intersecting series, twelve in 3
mm. measuring along the rows. Their openings correspond in
number to the zooecia in the branches beneath them. Zocecia
observed only in thin sections. On the reverse the branches are
straight or slightly zigzag, slender, thirteen or fourteen in 5
mm., rounded, somewhat variable in width, smooth when old,
granular and striated longitudinally when young. Dissepiments
short, in the middle about as wide as the branches, spreading
at their junction with them; on some portions of the zoarium,

560 PALEONTOLOGY OF ILLINOIS.

opposite in adjoining rows, on others alternate. Fenestrules
oval or subquadrate, about 0.5 by 0.2 mm., with fourteen in
1 cm.

The delicacy of the zoarium is its distinguishing feature.

Position and locality: Hamilton group, Rock Island, Illinois
and Davenport and Buffalo, Iowa.

HEMITRYPA PROUTANA Ulrich.

PL LVII, fig. l-lc.

Fenestella hemilrypa Prout, 1859. Trans. St. Louis Acad. Nat. Sci. Vol. I, p. 444, PL
XVII.flg. 4-4a.

Zoarium a large flabellate or semi-infundibular expansion,
more or less undulated toward the free margins. Obverse or
inner side protected by a delicate net-work, formed by the union
of longitudinal and transverse bars. The former consists of two
kinds, a slightly stronger and more prominent set, which are
developed directly over the center of the branches and united
to them by short supporting pillars. These may be called the
principal bars. A second set, which alternates with the prin-
cipals and may be known as the secondary bars, are suspended
over the space between the branches. The net-work is com-
pleted by a set of short transverse bars to which Prof. Hall
applies the appropriate term "scalte." According as the scalse
are developed oppositely or alternately in the adjoining longi-
tudinal series, the principal and secondary bars are straight or
zigzag, and the interstices, consequently, may be quadrate, pen-
tagonal or hexagonal. In this species the last form is less the
rule than usual. Measuring transversely, about twenty-six rows
of interstices occur in 5 mm.; longitudinally about twenty-four.
One to three small denticles sometimes project from the bars
into the interstices. When this net-work has been denuded,
which, on account of its delicacy, is often the case, the obverse
face of the branches is seen to be ridge-shaped, from 0.2 to 0.32
mm. wide, and generally twenty-six in 1 cm. The median carina
is neither sharp nor prominent, but carries small nodes (the
broken pillars that support the superficial net-work) at intervals
corresponding with the length of the zooecia. Dissepiments very

BRYOZOA. 561

•

short, depressed, about half as wide as the branches. Fenes-
trules long-oval, small, about 0.3 by 0.1 mm., and eighteen or
nineteen in 1 cm. Zoopcia in two ranges, twenty-three or twenty-
four in 5 mm., with small, widely separated, circular apertures,
and elevated peristome.

On the reverse the branches and dissepiments are on the same
plane, usually ridge-shaped, forming quadrangular fenestrules of
greater width than on the opposite face. On mature examples
the branches are smooth or very finely granular. On young
ones they are faintly striated.

This species is very common in the Warsaw beds, and occurs
also, but rarely, in the Keokuk group. It is closely allied to
the Keokuk H. plumosa (Fenestella plumosa Prout,) but differs
in having nine or ten fenestrules in 5 mm., while that species
has only 6.5 to 7.5 in the same space. There are most proba-
bly other differences, but the Keokuk species has not been ob-
served in a sufficiently good state of preservation to permit of
comparisons in the minute details of structure. As usual Prout's
types of H. plumosa were denuded of the superficial net-work.

Below are described two varieties of H. proutana.

Position and locality: Rare in the Keokuk group at Warsaw,
111., and Keokuk, Iowa; abundant in the Warsaw beds at War-
saw, and Monroe Co. in Illinois, and less common at Barrett's
Station, St. Louis Co., Mo. The species occurs also in the St.
Louis limestone of Caldwell Co., Ky.

HEMITRYPA PROUTAXA var. VERMIFERA n. var.

PL LVn, Fig. 5-5a.

This variety is represented by a number of specimens which
agree closely in their proportions with typical H. proutana.
The following differences have been noticed. The branches and
dissepiments on their reverse side are rounded instead of angu-
lar, and the fenestrules are more oval. The principal feature,
however, are certain peculiar, tubular, vermiform bodies, which
are irregularly distributed over and form part of the reverse
face of the zoarkim. They are about 2 mm. long and 0.5 mm.
in diameter, lie more or less nearly parallel with the branches,
—70

562 PALAEONTOLOGY OF ILLINOIS.

and have a sub-circular opening at the distal extremity. At
present I cannot give a satisfactory explanation of their nature.
Position and locality: Warsaw beds at Warsaw, 111.

HEMITRYPA PROUTANA var. NODULOSA n. var.

PL LVII, Fig. a-2c.

This form differs from the typical H. proutana in having the
interstices of the superficial net-work decidedly rayed or flori-
form, the small denticles which project from the sides of the
bars being more numerous and better developed. On the reverse
the branches are somewhat thinner, rounded, and bear numer-
ous small tubercles. The zoarium also does not attain the size
of H. proutana, but in the other measurements the variety
offers no striking difference.

Position and locality: Keokuk group, Keoktfk and Bentons-
port, Iowa, and Nauvoo, 111.

HEMITRYPA NODOSA Ulrich.

Pl.LVn.Fig.3.

The principal distinguishing feature of this species is the
nodose enlargement on the reverse of the branches opposite their
junction with the dissepiments. The branches are rounded,
eleven or twelve in 5 mm., with an average width of 0.2 mm.,
increasing from 0.15 to 0.3 or 0.4 mm. before bifurcation, the
dissepiments depressed, and less than half the width of the
branches; the fenestrules oval or sub-quadrate, twice as long as
wide, as wide as the branches, and seven or eight in 5 mm.
The superficial net-work is very much like that of H. proutana,
but the interstices are more nearly circular, about twenty in
5 mm., and the principal and secondary bars of about equal
strength.

The strong nodes and more slender branches distinguishes the
species from H. plumosa Prout sp. The specimen of which
several branches are represented by fig. 3a, simulates this species

BRYOZOA. 563

in the nodose character of the branches, • but in its measure-
ments it is identical with young H. aspera. That it is only a
peculiar example of that species is shown by the facts, that on
other portions the nodes are on the dissepiments, and that the
superficial net-work is spinous.

Position and locality: Keokuk group, Nauvoo, 111., Keokuk
and Beutonsport, Iowa. Not rare.

HEMITRYPA ASPERA Ulrich.

PL LVII, Pigs. 4-4f and 3a.

Zoarium a flat, rapidly expanding, flabellate expansion, at-
taining a height of 3 or 4 cms., though usually not more than
2 or 3 cms. It grew upon some cylindrical. body over which it
spread to form a strong base. The example figured is stronger
in this respect than usual, but a good idea of this portion of
the zoarium can be gathered from it. The different sets of bars
forming the superficial net-work are indistinguishable near the
base, but farther up where the branches bifurcate less frequently,
we find that the principal bars are elevated, generally opposite
each second scala, into strong spines, that all the bars are thin
and approximately of the same thickness, and that the inter-
stices are rather irregular in shape and size,but, almost invaria-
bly, nineteen or twenty in 5 mm., measuring longitudinally.

On the reverse near the base the branches and dissepiments
are rounded and thickened so as to be sub-equal and to make
the fenestrules sub-circular; their surface here is either smooth
or exhibits the remains of nodes. Farther up the fenestrules
are quadrangular, about 0.4 by 0.25 mm., and eight or nine in
5 mm.; the dissepiments half the width of the branches, some-
what depressed at the ends, but with the center elevated into a
prominent node. The branches are rigid, rounded and smooth,
and increase from 0.2 to 0.4 or 0.5 mm. before bifurcating;
about ten in 5 mm.; occasionally with a node that should have
been developed on a dissepiment.

The nodes on the dissepiments and the strong spines on the
superficial net-work distinguish this species from all others.

Position and locality: Keokuk group, Nauvoo, 111., Keokuk
and Bentonsport, Iowa.

564 PALEONTOLOGY OF ILLINOIS.

HEMITRYPA PERSTRIATA Ulrich.

PL LVII, Figs. 6-6a.

Zoarium infundibuliform, strongly folded in the upper half,
slowly expanding, 5 cms. or more in height, non-poriferous on
the outer side. Superficial net-work with the interstices or
openings circular, comparatively small, surrounded by a sloping
area, generally hexagonal, sometimes pentagonal or quadrate
in outline, about twenty in 5 mm.; the bars and scalse sub-
equal and sharply carinate. On the reverse the branches are
rounded, with from three to six strong longitudinal striae, and
from one to three series of small but prominent spines, the cen-
tral row being usually the most conspicuous. Average width
of branches about 0.3 mm.; just before bifurcation at least 0.5
mm., with ten or eleven in 5 mm. Bifurcations remote. Dis-
sepiments very short, much depressed, about half as wide as
the branches. Fenestrules narrow, oblong oval, about 0.5 by
0.15 mm., and fourteen or fifteen in 1 cm.

The favose net-work is very much like that of H. pateriformis,
but the reverse aspect of the two species is very dissimilar. The
zoarium of that species is also smaller and plate-shaped rather
than infundibuliform. The narrow fenestrules and strongly
striated branches distinguish the species from H. plumosa, Prout,
and H. proutana.

Position and locality: Keokuk group, Bentonsport and
Keokuk, Iowa.

HEMITRYPA PATERIFORMIS Ulrich.

PL LVII, Figs. 7-7c.

Zoarium patelliform, spreading rapidly from the short and
strongly ridged footstalk. It is further supported by numerous
root-like processes which extend downward from its under side
near the base. On the obverse or upper face, the bars forming
the superficial net work are carinated, the principal ones often
a little the strongest, the interstices regularly circular, rather
small, and alternating in adjoining rows, with about twenty-
one in 5 mm. On the reverse the fenestrules are sub-circular

BRYOZOA. 565

near the base. Here the dissepiments are thickened so as to
equal the branches and fenestrules in width Toward the outer
margin both the branches and dissepiments gradually become
thinner, and the fenestrules wider, and oval or even sub-quad-
rate in form. The surface of the branches is rounded and, when
well preserved, minutely granular. Between ten and eleven
branches occur in 5 mm., and in the same space longitudinally
nine or ten fenestrules.

The form of the zoarium, carinated bars of the superficial
net-work, small interstices, and rounded branches separate this
species from H. proutana. H. perstriata has very narrow fenes-
trules and strongly striated branches.

Position and locality: Keokuk group, Keokuk, Iowa.

ARCHIMEDES LeSueur (Owen), 1842.

(Amer. Jour, of Sci. Vol. 43, p. 19.)
(For generic diagnosis, see page 396.)

This remarkable genus of the FENESTELLID.*} is so far known
only from American Lower Carboniferous deposits. Here, how-
ever, the genus suddenly springs into prominence, first making
its appearance with four species in the Keokuk group, (includ-
ing the Warsaw beds*), two of them, the A. grandis Ulr., and
A. wortheni Hall, being the largest yet discovered. In the St.
Louis limestone, in which the Fenestellids are few and but illy
preserved, no species of Archimedes has yet been met with, but
in the overlying Chester group, the individuals and species again
become numerous, being, perhaps, the most characteristic fossils
of that division. Much diversity of opinion exists as to the
possibility of separating the species of the genus by the charac-
ters of the axis, but no one, so far as I am aware, has hereto-
fore given them much study, nor does it appear that any one
has taken pains to collect much material, and I do not wonder
then that so many palaeontologists have expressed themselves

* These beds are usually classified with the St. Louis group, but judging mainly
from the Bryoza, I should regard them as more intimately connected with the Keokuk
group. That they are beds of passage between these two groups will scarcely admit of
doubt.

566

as opposed to the specific divisions already established. A
parallel case is found in the old practice of uniting all Monti-
culiporoids under the specific names of Clitetetes lycoperdon
and Stenopora fibrosa; other cases in the old methods of classi-
fying the now well established species of Fenestelhi and Pinna-
topora Vine (Glauconome of authors). This multiplication of
species by the splitting up of old landmarks of palaeontological
nomenclature, being the result of special studies, is the strongest
evidence of progression, showing at the same time how ex-
tremely limited our knowledge of nature really is.

Five valid species were proposed by Prof. Hall in 1857, (Proc.
Am. Ass. Adv. Sci. Vol. 10), and in the following year (Geol.
Rep. Iowa, 1858), he proposed the name re versa for sinistral
examples of A. wortheni. To these the present work adds eleven
more, of which only two are from the Keokuk group, the re-
mainder being from the Chester. In proposing these species, I
fully appreciate the difficulties that the student will have to
meet in his attempts to identify them, yet, I can assure him,
that they are by no means insurmountable, nor any greater
than those which must be overcome in determining other groups
of organisms. The first thing to be done is to grasp the essen-
tial characters. These, of course, are surest determined by their
degree of prevalence and constancy, a test that can be applied
only when the material at hand is plentiful. During the course
of my work upon the genus I have had before me no less than
800 specimens, many of them nearly or quite perfect, this large
amount of material being contained partly in the State Museum
at Springfield, and partly in the extensive collections of
Bryozoa belonging to Mr. J. M. Nickles and myself. Some of
the species were represented by from 50 to considerably over a
hundred examples, two by only one each, 'while of the others
the numbers ranged from four to fifty. To determine the species
the variations in the following characters must be learned: (1)
the number of volutions made by the spiral axis in a given
space; this is generally very constant; (2) the outline and re-
lative diameter of the shaft and flange*; (3) when a portion or the

* The term "flange" is applied to the projecting portion of the axis that would be
equivalent to the "thread" of a screw. By the "shaft" I mean the subcylindrical portion
of the axis about which the "flange" revolves.

BRYOZOA. 567

whole of the fenestrated expansion is preserved, observe the
angle at which it diverges from the axial line; (4) the charac-
ters of the branches, fenestrules and zocecia, and their number
in a given space. The actual thickness of the shaft is available
only to a limited extent, while the direction of the volution is
only an individual peculiarity, both dextral and sinistral spirals
occurring in, perhaps, all the species. The zoarium was free,
and in some species at any rate, consisted of more than one
spiral axis. In every instance where two spirals were preserved
in connection the}' are turned in opposite directions. Two ex-
amples of this kind are represented on PI. LXIII, figs. 9b
and 14. The first shows on the left side how a new axis is
formed. The outer margin of the perforated frond is at first
slightly thickened, then gradually recurved upon its celluliferous
side until a complete volution has been made. The succeeding
volutions follow at regular intervals. The extreme constancy
with which these volutions take place in, for instance, A. coin-
munis and A. proutanus is remarkable, and seems to me a severe
rebuke for those palaeontologists who decry what they are
pleased to call a burdening of nomenclatnre by the foundation
of species upon trivial individual peculiarities. Who is to say
that these characters are trivial?*

Had I more space and plates at my disposal I would have
described and illustrated the minute internal characters of the
axis which in a number of species are quite distinctive. Magni_
fled views of the fenestrated expansion, of which I give full and
complete descriptions, would no doubt have materially aided
in the determination of the forms, but they had also to be dis-
pensed with. The following tabulated list of the species in
which the more important features of each are noted, will, I
hope, partially atone for the deficiencies. ,

* In the three years that have passed since writing the above, I have collected
nearly a thousand additional specimens of Archimedes, In this large number every
specie* here described, save A . perminimus, is represented, besides several species as
yet undescribed. The study of these specimens has been most gratifying to me, since
I was thereby afforded the very best demonstration of the specific validity of the char-
acTcrs upon which the species were founded. Nor did I experience even ordinary
difficulty in discriminating between the species.

568

PALAEONTOLOGY OF ILLINOIS.

BRYOZOA. 569

ARCHIMEDES NEGLIGENS Ulrich.

PL LXm, Fig. 7-7a.

Axis slender, lax, appearing delicate, faintly fusiform, at least
ten cm. in length; volutions moderately irregular, varying in
different examples from 3.6 to 4.5 in two cm. It is only in rare
instances that there are more than four in that space. Shaft
thin, slightly spiral. Fenestrated expansion from one to two
cm. wide, making an angle of about 75° with the axial line.
Branches slender, straight, 24 or 25 in one cm.; on the obverse
with very faint carina separating the two rows of zooecia, of
which there are about 26 in five mm. Apertures small, with
peristome. Fenestrules elliptical here, quadrangular on the re-
verse, a little longer than wide, about seven in one cm. Dis-
sepiments about half as wide as the branches.

The axis of this form cannot be confounded with those of any
other species known to me from this horizon. They resemble A.
terebriformis, of the Chester group, but the shaft is not swollen
below the flange, and the whole has a more delicate aspect.
Diani. of shaft of strongest ex. 1.5 mm.; No. of vol. in 2 cm., 4.
" smallest " 0.7 " " " 4.

average " 1.0 " " " 3.8.

another " 1.0 " " 4.6.

Position and locality: Keokuk group, Bentonsport and
Keokuk, Iowa.

ARCHIMEDES GRANDIS Ulrich.

PI. LXTTT. Fig. 10.

Axis very large and strong, the largest example seen, though
incomplete at both extremities, being nearly eighteen cm. long,
and making one volution to each cm. Of two other examples
one makes eight the other nine turns in ten cm. The shaft is
comparatively slender, and gradually spreads from the flattened
top of a flange into the smooth under side of the succeeding
flange, presenting on a large scale very nearly the appearance
noticed in A. invaginatus of the Chester group. Fenestrated
frond about five cm. wide, forming an angle of from 60° to 65°,
with the axial line. Branches slender, 23 or 24 in one cm.,
—71

570 PALAEONTOLOGY OF ILLINOIS.

slightly carinated on the obverse, and rounded on the reverse.
Zooecia about 22 in five mm., in two ranges. Fenestrules sub-
quadrate, longer than wide, 1(5 in one cm. Dissepiments as
strong as the branches.

Diameter of shaft 6 mm.; diameter of flange 2 cm.; number of
volutions in 10 cm,, 8, 9 or 10.

This fine species is related to both A. owenanus and A. wor-
theni. From the first the axis differs in having a wider flange
and longer volutions, from the second in having the under side
of the flange smooth, and in the outline of the shaft.

Position and locality: Keokuk group. All the specimens seen
are from Jersey Co., 111.

ARCHIMEDES OWENANUS Hall.

PI. LXHI, Fig. 6-6c.
Archimedes oicenana Hall, 1857. Proc. Amer. Ass. Ad. Sci., vol. 10. p. 178.

Axis probably very long, sometimes slender, at other times
very strong; volutions disproportionately rapid at the proximal
end, but soon they become longer; generally 2.5 occur in two
cm., more rarely three, and occasionally only two. The shaft
varies considerably in strength in different examples. Just
above the flattened top of the flange it is sub-cylindrical, spread-
ing a little in young examples toward the base of the succeed-
ing flange, which bends abruptly outward, the junction between
the two being marked by a more or less defined sulcus. Fenes-
trated expansion delicate, several cm. wide, leaving the axial
line at an angle of about 70°. Reverse only seen. Branches
narrowly rounded, 22 in 1 cm. Fenestrules oblong quadrate or
elliptical, as wide as the branches, the length equal to one and
a half times the width, with 13 or 14 in 1 cm. Dissepiments as
strong as the branches.

Diam.of shaft of strongestex., 5.7mm.; No. of vol. in 2 cm., 2.3.

" smallest " 1.8mm.; " " 2.7.

" " " average " 2.9mm.; " " " 2.2.

The above description refers to the form usually identified
with Hall's A. owenanus. The very incomplete original descrip-
tion contains nothing that does not agree with it. The posi-
tion of the species is somewhat intermediate between A. wor-

BRYOZOA. 571

theni Hall, and A. terebriformis Ulr., but is not near enough
to either to require detailed comparisons.

Position and locality: Keokuk group, Keokuk, Iowa, Appa-
noose (Hall), and three miles northeast of Quincy, 111.

ARCHIMEDES WORTHEXI Hall.

PL LXm. Fig. 8-«a.

Archimedes wortheni HalL 1857. Proc. Amer. Ass. Ad. Sci., voL 10, p. 178.
Archimedes wortheni Hall, 1858. Pal. Iowa, p. 651, PL XXII, flg. 3, 4a. 4b, 5a, 5b.
Archimedes recersa HalL 1858. Ibid. p. 652, PI. XXH, flg. 2.

Axis large, sub-fusiform, sometimes attaining a length of
thirty cm. or more. Volutions regular, dextral and sinistral,
varying in different examples from 5 to 6 in 5 cm. Shaft
very short, comparatively small, abruptly spreading into the
wide flange, the junction between them sharply defined. Upper
end of flange flat or slightly concave; lower side usually a very
little convex, and uneven, frequently with rather regular verti-
cal depressions. Fenestrated expansion as much as six cm.
wide, diverging from the axial line at an angle of 65°. On the
obverse the branches are rigid and closely approximated, the
fenestrules appearing very narrow. Separating the two rows of
zocecia there is a strong carina, carrying a series of compressed
spines. Zooecia about twenty-six in 5 mm., with small, promi-
nently elevated apertures, very regularly arranged. On the re-
verse the branches are more slender, with from 23 to 25 in 1
cm.; the fenestrules are sub-oval, quite as wide as the branches,
about once and a half their width in length, and 16 in one cm.;
and the dissepiments generally a little stronger than the
branches.

Diam.of shaft, largest ex. 10.0; No. vol. 5 cm., 5.7; diam. fl'ge,28.
smallest " 5.1; " " " 6.0; " " 15.
average " 7.2; " " " 5.4; " " 20.

At Bentonsport, Iowa, there occurs what may be a small
variety of this species. The length of the axis, as is shown by
a nearly complete example, was not much more than 9 cm.
There are eight volutions in 5 cm. Another example has only
seven in that distance.

Hall describes A. wortheni, as having occasionally three rows
of apertures below a bifurcation, and sometimes with zooecia on

572 PALEONTOLOGY OF ILLINOIS.

the dissepiments. None of the numerous examples before me
exhibit anything of the kind, and I do not doubt that both
assertions are based upon defective observation.

Position and locality: Warsaw beds.

This is one of the most abundant and characteristic fossils of
this horizon.

ARCHIMEDES PERMINIMUS Ulrich.

PI. LXIII, Fig. 13 and 11, pars.

Of this species the example figured is the only one seen. Its
axis is, however, so minute in its proportions that I cannot
hesitate in pronouncing it distinct from all the other species
known to me. In the form and construction the axis reminds
us a little of the much larger species A. terebriformis, and it
might be urged that A. perminimus is only the terminal or young
condition of that species. But such an explanation would not
occur to any one who has devoted only a moderate amount of
time to the study of these peculiar Bryozoa. The number of
volutions in a given space is approximately the same through-
out the length of the spiral axis.

In the specimen under consideration there are four volutions
in 5 mm. The shaft of the axis at its thickest part is only
0.25 mm. in diameter. The fenestrated expansion must have
been very narrow. It is not preserved so as to enable me to
give measurements of its minute features. The branches seen
bifurcate at each dissepiment, and are about as wide as the
fenestrules. The latter are elliptical, with a length equalling
about twice the width of a branch.

Position and locality: Chester group, Chester, 111.

ARCHIMEDES COMPACTUS Ulrich.

PI. LXIII, Figs. 2-2e (?2c).

Axis small, sub-fusiform, not over 6 cm. in length, usually
about 3.5 to 4.0 cm.; volutions varying from 9 to 11 in two
cm.; shaft comparatively strong, nearly regularly concave on
each side. Fenestrated expansion less than one cm. wide, form-
ing an angle of 75° with the axial line. Branches slender, about
as wide on the reverse as the fenestrules, 24 in one cm. Fenes-

BRYOZOA. 573

trules once and a half as long as wide, oval or sub-quadrate,
about 16 in one cm. Dissepiments rather thick. Obverse not
observed. As determined by thin sections, there are about 25
zooecia on each side of a branch in five mm.

The section represented by fig. 2c most probably does not

belong to this species. It had a much stronger shaft, while the

angle of the fenestrated expansion, as well as the outline is

different. In these features it is exactly like the A. intermedius.

Thick, of shaft of strongest ex. 2.7 mm.; No. of vol. in 2 cm., 9.

" smallest " 1.0 " 11.

" average " 2.0 " " " " 10.

Position and locality: Chester group, Sloan's Valley, Ky., and
other localities.

ARCHIMEDES COMMTTNIS Ulrich.

PI. LXm, fig. l-ld.

Axis slender, over twelve cm. in length, approximately of the
same diameter throughout; volutions very regular, 7 or 8 in 2
cm.; shaft moderately strong, rather deeply and regularly con-
cave on each side, so that it is difficult to distinguish the dis-
tal from the proximal extremity. Fenestrated expansion nearly
always broken away, apparently not over one cm. in width,
forming an angle of from 85 to 90 degrees, with the axial line.
Branches rounded on the obverse, without a keel, 24 or 25 in
one cm.; the zooecia about twenty on each side in five mm.,
with small apertures and elevated peristome, separated by an
interspace equal to once and a half their diameter. Fenestrules
elliptical, nearly twice as long as wide, about 15 in one cm.
Dissepiments thin.

Thick, of shaft of strongest ex., 2 mm.; No. of vol. in 2 cm., 8.
" " " smallers " 1 " " " 7%.

" average " 1.3 " " " 8.

The smaller axis, more regular and numerous volutions dis-
tinguish this species from A. swallovanus Hall. In A. inter-
medius there are about six volutions in two cm., and the fene-
strated expansion forms an angle of 72° with the axial h'ne.

Position and locality: Chester group. This is the most com-
mon as well as the most constant species of the genus. It

574 PALEONTOLOGY OF ILLINOIS.

occurs at most localities in the group, but is especially abund-
ant at Sloan's Valley, Pulaski Co., Ky.

ARCHIMEDES INTERMEDIUS Ulrich.

PL LXIII, flg. 2c.

This form, which is also rather abundant, closely resembles
both A. communis Ulr. and A. swallovanus Hall. It differs from
the former in having from 5% to 6% volutions in two cm., and
in having a stronger axis. The angle formed by the fenestrated
expansion is also smaller, being about 72 degrees, while in A.
communis it is not less than 85 degrees. The last comparison
holds good also for A. swallovanus. The axis of Hall's species
makes from 4% to 5 volutions in two cm., and is generally also
much stronger.

The Kentucky examples usually make one-half a volution
more in two cm. than the Illinois specimens. The section
figured was taken from an example from Chester, 111., which
had 6% volutions in that distance, and is an exception to the
.rule.
Thick, of shaft of strongest ex., 4.5 mm.; No. of vol. in 2 cm., 6.

" smallest " 2.0 " " " 5%.

" •«• " average " 3.0 " " " " . 6.

Position and locality: Chester group. Chester, 111., and
Sloan's Valley, Ky., and other localities. Common.

ARCHIMEDES SWALLOVANUS Hall.

PL LXIII, flg. 12-12d.
Archimedes swallovana Hall, 1857. Proc. Amer. Asso. Ad. Sci. vol. 10, p. 178.

Axis rather strong, of considerable length, approximately of
the same diameter throughout (i. e. not appreciably fusiform);
volutions regular, 4% to 5 in two cm.: shaft strong but deeply
.concave, generally forming a regular curve, sometimes a little
straightened above, or again quite straight at the sides (see
fig. 12a). Fenestrated expansion of unknown width, forming
an angle of about 85° with the axial line. Branches 22 in one
cm., with a scarcely. perceptible simple keel, and two ranges of
zooecia; in each 19 or 20 occur in five mm. Fenestrules ellipti-
cal, twice as long as wide, about 14 in one cm.

BRYOZOA. 575

The smaller number of volutions, and the larger and stronger
axis, distinguish this species from A. communis and intermedius.

It has not been found in the Chester group localities of Ken-
tucky, where both of these species are abundant.
Diam. of shaft of strongest ex. 6.7 mm.; No. of vol. in 2 cm., 5.

another " 5.0 " ." " 4&

smallest " 2.8 " " " " 5.

" average " 4.0 " " " 5.

Position and locality: Chester group, at Chester and other
localities in Illinois.

ARCHIMEDES TEREBRIFORMIS Ulrich.

PI. LXm, figs. 5-oc.

Axis rather slender, just a little fusiform, the largest specimen
seen, which appears to be almost complete, is ten cm. long;
volutions quite regular, varying in different examples from 3
to 4.2 in two cm.: shaft comparatively thin, distinctly spiral,
thickened just below the spiral flange, the thickening best shown
in medium sized specimens. Fenestrated expansion of unknown
dimensions, forming an angle of from 60 to 65° with the axial
line.

This form is readily distinguished from ah1 the associated
species by the spiral form of the shaft, and the swelling just
beneath the flange. In other respects it compares closely with
A. negligens, from the Keokuk group. The collection before me
contains eight axes of what is probably a variety of this spe-
cies. They lack the swelling below the flange, and have con-
stantly 4.8 to 5 volutions in two cm. So far as observed they
do not differ in any other respect from the typical specimens.
Diam. of shaft of strongest ex. 2.5 mm.: No. of vol. in 2 cm., 3.1.
smallest ;- 1.1 " " " 3.

average " 2.0 " " " " 3.

Position and locality: Chester group, Chester, Illinois, and
rarely at Sloan's Valley and Grayson Springs, in Kentucky.

ARCHIMEDES IXVA<;I.\ATUS Ulrich.

PL LXD3. figs, lla, lie.

Axis rather strong, usually a little curved, over ten cm. long
when complete, diminishing very gradually in strength toward

576 PALEONTOLOGY OF ILLINOIS.

each extremity; volutions regular, varying in different exam-
ples from 3.7 to 5 in two cm.; shaft comparatively slender just
above the flange. The appearance of a series of invaginated
oblique cones is more striking in this species than in any other.
Fenestrated expansion two cm. or less in width, forming an
angle of from 55 to 60° with the axial line. On the reverse
the branches are narrowly rounded, from 23 to 25 in one cm.,
near the axis as wide as the fenestrules, becoming narrowed
and somewhat zigzag toward the outer margin; fenestrules sub-
quadrate, sometimes perceptibly pentagonal or hexagonal; 16
or 17 in one cm.; dissepiments nearly as strong as the branches.
On the obverse the branches are usually without a keel, but a
few spines may be detected. Zooecia in two ranges, about 26
in five mm., with small aperture and peristome. On this side
the fenestrules are narrower and elliptical.
Diam. of shaft of strongest ex. 4.5 mm.; No. of vol. in 2 cm., 4.2.

" " smallest " 2.3 " " " " 4.5.

" " average " 3.1 " " " " 4.0.

The larger size, less numerous volutions, and the compara-
tively greater extent of the flange, as well as the absence of a
spiniform keel and the smaller zooecia, distinguish this species
from A. proutanus, to which it is closely related. A. intermedius
Ulrich, might be confounded with it, but a careful comparison
will show among other differences, that while in that form the
frond diverges from the axial line at an angle of about 72°, it
takes place in this species at an angle of only 55 to 60°

Position and locality: Chester group, Chester, 111.

ARCHIMEDES PROUTANUS Ulrich.

PI. LXIII, figs. 3-3d, and 11, lib.

Axis slender, as usual both sinistral and dextral, very gradu-
ally diminishing toward each extremity, appearing generally as
of uniform size throughout. The longest specimen seen is of
the average thickness, nearly complete, and ten cm. long. Volu-
tions very regular, but varying in different examples of the typi-
cal form from 6 to 8 in two cm. Six examples before me belong
apparently to a variety of the species. Two of these are repre-
sented by figures 11 and lib. These differ from the typical form
principally in being stronger and in having from 4.5 to 5.5

BRYOZOA. 577

volutions in 2 cm. Shaft rather thin just above a flange, then
gradually thickening and slightly curved outward to the mar-
gin of the succeeding flange. The under side of the flange is dis-
tinctly marked by the branches in the typical form, but much
less distinctly in the variety mentioned. Fenestrated expansion
usually not over one cm. wide, forming an angle of about 65°
with the axial line. Branches about 21 in one cm., rounded on
the reverse, with a moderate keel on the obverse, separating
two rows of small scarcely elevated zooecia apertures, of which
from 20 to 22 occur in five mm. Keel with sharp spines three
or four to each fenestrule. Fenestrules subquadrate, a little
longer than wide, 16 or 17 in one cm. Dissepiments thin,
scarcely half the thickness of the branches. In the large variety
the fenestrules are somewhat longer, there being only about 15
in one cm.
Diam. of shaft of strongest ex. 1.8 mm., No. of vol. in 2 cm., 7.0.

smallest " 1.2 " " " 7.2.

average " 1.5 " " 6.7.

av. large var. 2.5 " " " " 5.0.

Although quite distinct and nearly as abundant, it requires
care to distinguish this species from A. communis. These two
species agree closely in the number of volutions and size of the
axis. However, with a little experience the student will soon
learn to detect their individual peculiarities at a glance. Thus
in A. proutanus the flange is directed toward the distal extrem-
ity and furrowed on the lower side, while in A. communis the
flange and fenestrated expansion extends out from the shaft at
nearly a right angle. The form mentioned as a large variety
may prove a distinct species. The specimens approach A. in-
vaginatus in form and were at first supposed to belong to that
species, but as the characters of the fenestrated expansion
agree more closely with typical A. proutanus than A.invaginatus,
I have thought it best to refer them, provisionally, as above.
Position and locality: Common at Sloan's Valley, Ky. It
also occurs at Chester, 111., and other localities in the State.

—72

578 PALAEONTOLOGY OF ILLINOIS.

ARCHIMEDES MEEKANUS Hall.

Pl.LXIII,flg.4.
Archimedes meekana Hall, 1857. Proc. Amer. Ass. Ad. Sci. Vol. 10, p. 178.

Axis slender, probably not exceeding seven cm. in length; sur-
face minutely granulose; volutions 4 to 5 in two cm., shaft
thin, faintly spiral, and spreading gradually into the flange, the
lower side of which is generally furrowed (7. e. showing the base
of the branches.) Fenestrated expansion of unknown width,
diverging from the axial line at an angle of 65°. Branches
rounded on the reverse, wider and faintly carinate on the ob-
verse, the carina with closely crowded small spines. Zooecia in
two ranges, 25 or 26 in five mm., with very small elevated
apertures. Fenestrules subquadrate on reverse, slightly longer
than wide, about 20 in one cm. Dissepiments two-thirds as wide
as the branches and even with them.
Diam. of shaft of strongest ex. 1.0 mm.; No. of vol. in 2 cm., 4.9.

" " smallest " 0.6 " 5.0.

average " 1.1 " 4.3.

another " 1.0 " 4.0.

In its general appearance the axis of this species resembles
that of A. proutanus Ulr., but differs in being more loosely
wound. The zocecia are considerably smaller, and the fenes-
trules and branches more numerous in a given place.

Position and locality: Chester group; not uncommon at Ches-
ter, 111. Eare at Sloan's Valley and Grayson Springs, Ky.

ARCHIMEDES DISTANS Ulrich.

PI. LXIII, fig. 9-9b.

Axis very slender and delicate, probably not exceeding eight
cm. in length; volutions 3 to 3.5 in two cm.; shaft delicate,
sub-spiral, spreading gradually into the flange, the lower side
of which is, particularly in young examples, strongly furrowed
vertically. Perforated frond from 1 to 4 cm. wide, diverging
from the axial line at an angle of from 45 to 50 degrees. On
the reverse the branches are rounded, about 23 in one cm., the
fenestrules oblong quadrate, being about as wide as the branches
and one-half of the width longer than wide, with 19 or 20 in

BRYOZOA. 579

one cm.; the dissepiments one-half as wide as the branches and
nearly on a level with them. On the obverse the dissepiments
and branches are carinate. the keel with small spines corres-
ponding in number with the zooecia, of which there are about
22 in five mm. Apertures of moderate size, with slight peris-
storne, usually two. sometimes three to each fenestrule.
Diaui. of shaft of strongest ex., 1.4 mm.; No. of vol. in 2 cm., 3.5.

" smallest ik 0.8 " " " " 3.5.

" average " 1.1 " " " " 3.3.

This species differs from A. mefikanus Hall, in the longer volu-
tions, larger zocecia, and smaller angle of divergence of the
feuestrated frond from the axial line.

Position and locality: Chester group. Not uncommon at
Chester. 111. I have also seen several examples from Sloan's
Valley, Pulaski Co.. Ky.

ARCHIMEDES SUBLAXUS Ulrich.
PI. Lxm, fig. 14.

Of this species the specimen figured is the only one seen. It
consists of two axes, one sinistral the other dextral, which ob-
viously formed part of a single zoarium. The volutions are
completed at intervals of 11 or 12 mm., the shaft slender and
more or less spiral, from 1 to 1.3 mm. thick, spreading slowly
upward into the small flange. Fenestrated expansion 1.5 cm.
or less in width, diverging from the axial line at an angle of
38° to 40°. On the reverse the branches, of which there are
22 or 23 in one cm., and dissepiments are rounded, the latter
two-thirds as thick as the former: the fenestrules a little longer
than wide, as wide as the branches, of subquadrangular form, with
about 16 in one cm. On the obverse the fenestrules are a little
narrower, and the branches proportionately wider, with an in-
conspicuous, faintly spinous keel. Zocecia in two ranges, with
small apertures and slightly elevated peristome: about 26 in
5 mm.

The spiral axis of this species is more loosely enrolled and
the shaft thinner than in any other of the genus excepting A.
laxus Hall. In other respects it resembles the A. owenanus Hall,
of the Keokuk limestone.

Position and locality: Chester group, Chester, 111.

580 PALEONTOLOGY OF ILLINOIS.

ARCHIMEDES LAXUS Hall.

PL LXHI, flg. 15-15a.
Archimedes laxa Hall, 1857. Proc. Amer. Ass. Ad. Sci. Vol. 10, p. 178.

Helicopora archimediformis Claypole, 1883. Quar. Jour. "Geol. 8oc. Vol. 39, p. 34, PI.
IV, flg. 3,4.

Axis very loosely enrolled, consisting of scarcely more than
the thickened edge of the spiral frond; completing a volution
at intervals of 2.5 cm. or more. Number of volutions probably
not more than four. Fenestrated expansion diverging from the
axial line at an acute angle, wide, the greatest width observed
5.5 cm., slightly decumbent toward the free margin. On the
reverse the branches are narrowly rounded, becoming zigzag
and thinner as they near the outer margin; 20 or 21 in one
cm. Fenestrules oblong quadrate, or somewhat hexagonal, as
wide or wider than the branches, with a length equal to nearly
twice the width; about 13 in one cm. Dissepiments usually as
strong or stronger than the branches, and sometimes more
prominent. On the obverse the fenestrules are narrow, ellipti-
cal, the branches stronger and rigid, subangular, but without
a keel. Zooecia with rather small circular apertures more than
their diameter apart, and very slight peristome, in two ranges
excepting just below a bifurcation where some of the branches
exhibit three rows; 21 or 22 in five mm.

As above cited, Prof. Claypole referred a specimen of this spe-
cies to his new genus Helicopora. While agreeing that A. laxus
closely approaches his genus, I am still indisposed to accept his
arrangement, since it scarcely admits of question that the form
is nothing more than a loosely coiled Archimedes. The Silurian
type of his genus (H. latispiralis) does not appear to be so.

Position and locality: Chester group. Fragments are not un-
common at Chester, Illinois, and Litchfield, Ky.

LYROPORA Hall, 1857.

(Proc. Amer. Ass. Ad. Sci., vol. 10, p. 179.)
(For generic diagnosis see page 390.)

This genus, although presenting but few characters to distin-
guish it from either Fenestella or Polypora, is nevertheless a
very convenient and natural group of Lower Carboniferous

BRYOZOA. 581

Bryozoa. The relation to Polypora is in every way equivalent
to that between Archimedes and Fenestella, the only difference
being that while in Archimedes the stony support forms spiral
volutions, in Lyropora it is Y- or U-shaped. The form and
other peculiarities of the support are quite const ant J*f or each
species, and when this portion of the zoarium happens to be
similar in two species, as for instance in L. quincuncialis Hall,
and L. ranosculum Ulr., and L. subquadrans Hall, and L.
divergens Ulr., marked differences are found in the struc-
ture of the net -work. This is more or less different in all the
cpecies. and I have found it possible to determine with certainty
the specific relations of the merest fragments.

Six species, and possibly two more, beside one variety, are
known to possess the characteristic support of the genus. With
the exception of L. i*etroi-sa M. & "W., a rather rare species in
the Burlington limestone, all are from the Chester group.

LYKOPORA RANOSCULUM Ulrich.

PL LVm, Fig. l-lc.

Zoarium large, free, a foliate expansion spread between the
recurved ends of a strong support. Support parabolic, the
arms diverging at a variable degree, subcircular or oval in
cross section, consisting of exceedingly thin, transversely grano-
striate concentric layers of sclerenchyma. which are successively
deposited upon the lateral margins of the strongly convex
fenestrated expansion At the base of the support there is com-
monly an obtuse knob-like thickening. Fenestrated expansion
celluliferous oh the convex side. Here the branches vary in
thicknegs from 0.4 to 0.6 mm., with about 15 in one cm.; their
surface rounded and, when perfect, with a somewhat irregular
series of strong tubercles, two or three to each fenestrule, along
the middle; the zooecia with circular or sometimes irregularly
inflected apertures, about 0.09 mm. in diameter, separated by
interspaces as wide or wider, and arranged in from three to five
(usually four) only moderately regular alternating ranges, 21
or 22 in five mm.; the fenestrules irregularly oval, eleven in one
cm.; the dissepiments short, their width as great or greater
than the length of the fenestrules. On the reverse the fenes-
trules are circular or round oval and larger than on the ob-

582 PALEONTOLOGY OF ILLINOIS.

verse, the branches and dissepiments longitudinally striated in
the young state, granulose, or with short vermicular striae in
older stages.

This well marked species was at first supposed to be identical
with the L. lyra of Hall, but upon investigation proves to be
quite distinct, as it now appears that that name was applied to
only a variety of his L. subquadrans. The features that sepa-
rate it from Hall's species are the stronger and subcylindrical
form of the support, the absence of a slender base and the
strongly convex form of the fenest rated expansion. The sup-
port closely resembles that of L. quincuncmlis Hall, but that
species has, excepting below a bifurcation, only two rows of
zooecia on the branches.

Position and locality: Chester group. Fragments of this
specie are rare at Chester and Kaskaskia in Illinois. They are
more abundant and better preserved at Sloan's Valley, Pulaski
Co., Ky.

LYROPORA SUBQUADRANS Hall.

PL LVIII, Fig. 2-2e.
Lyropora subquadrans Hall, 1857. Proc. Amer. Ass. Ad. Sci., vol. 10, p. 180.

Zoarium with the thickened support and fenestrated expan-
sion spread nearly in a plane, or with the celluliferous side
somewhat convex. Support comparatively thin, pedunculate at
the base, with the arms usually direct from the base, and di-
verging at an angle of 80° or more. Sometimes the sides of
the support near the base are irregularly wrinkled. Entire
height of zoarium not known to exceed six cm. On the obverse
the branches appear rather rigid, generally about 0.6 mm. wide,
13 or 14 in one cm.; subangular, with a central row of small
tubercles, five or six to each fenestrule. Zooecia with small cir-
cular apertures, about 0.075 mm. in diameter, arranged regu-
larly in four ranges, which are increased to five or six below a
bifurcation; 22 or 28 in five mm. Fenestrules irregularly ellip-
tical, about ten in one cm., separated by slightly depressed
strong and short dissepiments, having a width about equal to
the length of the fenestrules. On the reverse the branches and
dissepiments are thinner and narrowly rounded, and the fenes-
trules larger, varying in form from suboval to subquadrate.

BRYOZOA. 583

The less strong and different form of the support, the more
rigid branches, more regular arrangement of the zooecia aper-
tures, and sub-quadrangular form of the fenestrules on the re-
verse, distinguish This species from L. ranosculum Ulr. Hall's
description of the obverse differs somewhat from the above, but
there can be no doubt about the identity of the specimens here
described with the original exampi

I have failed to find any reliable characters upon which to
distinguish Hall's L. lyra from this species. Fig. 2a (PI. LVIII)
represents a small example of what I regard a# the typical form
of L. subquadrans, while fig. 2 and 2b represent examples that
are intermediate between it and the L. lyra form. A specimen
before me (obtained since the plates were lithographed) seems
to agree in every particular with Hall's description of his lyra.
It also agrees with figure 2 in every respect excepting slight
modifications in the form of the support, such as incurving
abruptly outward and upward from the slender peduncle or
base, instead of being nearly direct. Such small modifications,
unless accompanied by more important differences, are scarcely
sufficient even for varietal separation, since nearly every speci-
men examined by me offers some slight peculiarity. The L. sub-
quadrans being the normal and more abundant form, it seems
desirable that its name, although following L. lyra in the
original paper, should take precedence.

Position and locality: Chester group. Rather common at
Chester, 111., and Sloan's Valley, Ky.

LYROPORA QUIXCUNCIALIS Hall.

PL LVm, Fig. 3-3d, and PL LV. Fig. 7-7c.
Lyroporo. quincuncialis Hall 1857. Proc. Amer Ass. Ad. Sci., vol. 10, p. 180.

In this species the support is very much as in L. ranosculum,
but differs in being less strong and rather narrow oval instead
of subcircular in cross section. The fenestrated expansion is
also less convex, and in every respect the zoarium is less ro-
bust. Branches, on the obverse, rounded, 0.25 to 0.5 mm. wide,
with a series of small tubercles along the middle, and two
ranges of cell apertures excepting below a bifurcation where
there are three: 24 or 25 in one cm. Apertures small, about
0.07 mm. in diameter and twenty-five in 5 mm. Fenestrules

584 PALEONTOLOGY OF ILLINOIS.

elliptical, sometimes appearing oblong quadrate, 16 or 17 in
one cm. Dissepiments rather prominent. On the reverse the
dissepiments are often more prominent and stronger than the
branches, often forming short oblique or transverse ridges. At
other times they are of about equal thickness and leave regular
subcircular or oval fenest rules, having a diameter nearly or
quite equal to the width of the branches.

Position and locality: Chester group. Fragments are com-
mon at Chester, 111., and other localities, but good specimens
are rare.

LYROPORA DIVERGENS Ulrich.

PI. LVIII, Fig. 4-4b, 4d.

Zoarium small, with a peduncle or point of attachment below,
from which the arms of the thickened support diverge at nearly
a right angle and approximately in a direct line; the whole
spread nearly upon the same plane. On the obverse the branches
are usually, a little fiexuous and subangular, with a row of
small tubercles, about three to each fenestrule, along the middle;
18 or 19 branches in one cm. Zooecia in two rather irregular
ranges excepting a short distance below a bifurcation where
there are three; apertures with a distinct peristome, compara-
tively large, about 0.1 rnm. in diameter, and 22 in five mm.
Fenestrules irregularly elliptical, indented by the zocecia aper-
tures, 12 or 13 in one cm. Dissepiments subangular, nearly as
high as, and thinner than the branches. On the reverse the
branches and dissepiments are rounded, of nearly equal thick-
ness, and covered with fine vermicular striae; the fenestrules
round oval, varying in width with age, in younger examples
being wider than the branches, in old ones narrower.

In having two rows of zocecia this species resembles L. quin-
cuncialis Hall, but differs in the form of the support, in having
the expansion spread in a plane, and the zooecia, fenestrules and
branches a little larger. The apertures too are larger and have
a distinct peristome, a feature not noticed in that species. The
two ranges of zo(Pcia and the smaller branches will distinguish
it from L. subquadrans Hall.

Position and locality: Chester group, Chester, 111., and Sloan's
Valley, Pulaski Co., Ky.

BRYOZOA. 585

LYROPORA OVALIS Ulrich.

PL LYin, Fig. 5-5b, and PI. LY, Fig. 8.

Of this species I have seen only the imperfect example figured.
It does nott preserve any of the basal portion of the support,
but the sides of the expansion are thickened in the manner
usual for the genus. Contrary to the rule the reverse is the con-
vex side. Here the branches are rounded and appear to inoscu-
late, forming a regular net-work, leaving suboval or circular
fenestrulHs. about ten in the length of 1 cm. Branches about
sixteen in 1 cm., with a nearly smooth surface; their width, as
a rule, is a little less than the transverse diameter of the fenes-
t rules. The obverse being buried in the matrix, the arrange-
ment of the zooecia and and other features were determined by
means of thin sections. These show that the zocecla are larger
than usual (especially wider) there being about twenty in five
mm. The prevailing arrangement is in two ranges, but three
rows occur for a distance of 2 or 3 mm. below the bifurcations,
i own by vertical section (PI LV, fig. 8,) the inferior hemi-
septum is situated higher up on the anterior wall than in other
species.

The two ranges of zooecia ally this species to L. divergens
Ulr.. and L. c/uincuncialis Hall, but the net-work is considerably
larger than in those species. Both L. subquadrans Hall, and
L. ranosculuw L'lr.. have from three to five rows of apertures.

Position and locality: Chester group, Grayson Springs, Ken-
tucky.

POLYPORA McCoy, 1844.

(Synop. Carb. Foss. Ireland, p. 206.
(For generic diagnosis see page 396..)

In my estimate of this genus I regard such forms as P. shu-
niardi and P. rai-soviensis. as representing its most typical
phase. McCoy's P. dendroides is one of a series (to which P.
cestriensis, P. tuberculata. and P. gracilis also belong), that
approaches Thamniscus too closely to make it a desirable type.
I regard it as farther removed from P. shumardi than are the
numerous two and three ranged forms/
—73

586 PALEONTOLOGY OF ILLINOIS.

POLYPORA SHUMARDI PrOUt.

PI. LV, figs. 2-2d.

Polypora shumardi Prout, 1859. Trans. St. Louis Acad. Sci. Vol. 1, p. 271. PI. 16.

fig. 3-3b.

Polypora shumardi Hall, 1885. Bept. State Geol. for 1884, p. 35 PI. 1, flg. 5.
Fenestella cultellata Hall, 1881. Trans. Alb. Inst. Vol. X. Abstract p. 21.

Fenestella (Polypora) cultellata Hall, 1883. Rept. State Geol. for 1882. Explanation to

PI. 29.

Fenestella cultellata Hall. 1886. Eept. State Geol. for 1885. Explanation to PI. 41.
Fenestella cultellata Hall, 1887. Pal. N. T. Vol. 6, p. 160.

Zoarium a large irregular fan-shaped expansion, the largest
fragment seen being over 10 cm. high, and 12 cm. wide. Near
the base and along the free margins there are, usually, strong
root-like processes which may be attached to foreign bodies.
Branches rather strong and straight, subangular, varying from
0.6 to 1.0 mm. in width, with eight or nine in 'one cm.; along
the middle, on well preserved examples, with a series of elong-
ate, strongly projecting, sharp, elevations or spines, about one
to each fenestrule. Dissepiments half the width of the branches,
depressed, rounded, often with a sharply margined irregular ex-
cavation or channel. Fenestrules narrow, elliptical, eight or
nine in 1 cm. Zocecia generally in four or five alternating long-
itudinal ranges, increasing to six or seven before bifurcation;
about seventeen in 5 mm. Apertures circular, rather large,
regularly and closely arranged, the not very well developed
peristomes being almost in contact laterally. On the reverse
the branches and dissepiments are rounded, commonly smooth,
nearly on the same plane, the latter expanded at their junction
with the former and about 0.6 mm. in length.

A very abundant and easily recognized species. Some of the
silicified examples show the superior hemiseptum very clearly as a
narrow crescentic plate projecting obliquely downward and forward
from the posterior basal margin of the "vestibule." Other speci-
mens have the superficial aperture closed by the usual opercular
plate, the small perforation of which may be open or closed by
a round stopper.

Position and locality: Upper Helderberg group. Falls of the
Ohio, and Utica, Indiana.

BRYOZOA. 587

POLYPORA BURLFNGTONENSIS Ulrich.
PL LIX, figs. 2-2a.

Zoarium flabellate, at least 6 cin. wide, with strong root-like
processes at the base. On the reverse the branches are moder-
ately strong and straight, rounded, smooth, 0.6 to 1.0 mm.
wide, and seven or eight in 1 cm. Dissepiments rather slender,
somewhat depressed, one-half or less than half the width of the
branches. Fenestrules subquadrate, 4.5 to 5 in 1 cm., about
as wide as the branches, averaging 1.6 by 0.8 mm. None of
the specimens show the obverse side satisfactorily, but as is
learned from thin sections, the zocecia are often in four, gener-
ally in five, and sometimes (just before bifurcation) in six alter-
nating longitudinal series. Their apertures are about their
diameter apart, with fourteen or fifteen in 5 mm.

Bryozoa are so rare in the Burlington limestone that the de-
scription of poorly preserved material from it is, in a measure,
excusable. Moreover, the nature of the rock is such, that
good specimens of this class are almost unknown. As near as
can be determined P. burlingtonensis is closely allied to P. hal-
liana Prout, of the Keokuk strata. The latter differs in having
the reverse of the branches more narrowly rounded, and six
fenestrules where this species has 4.5 to 5. Better specimens
would probably show other distinctions.

Position and locality: Burlington limestone, Burlington, la.,
and Henderson Co., Illinois.

POLYPORA HALLIANA Prout.

PI. LIX, flgs. 5-oc.

Polypora haUiana Prout., 1860. Trans. St. Louis Acad. Sci. Vol. 1, p. 580.
Polypora haUiana Prout, 1866. Geo. Surv. HI. Vol. 2, p. 421. PL XXI. flg. 4-4b.
(Not Polypora haUiana Nich., 1874. Pal. Ont. p. 99.)

Zoarium large, expanding rapidly from a short, thick, finely
striated foot-stalk, so that the margins quickly meet beneath
it, or pass and overlap each other. The largest example seen
measures 11 cm. from the outer margin to the sub-central foot-
stalk. The inner half of the expansion is spread nearty in a
plane, but towards the margins the frond is somewhat undu-
lated. Near the footstalk the branches bifurcate frequently, are

588 PALAEONTOLOGY OF ILLINOIS.

much curved, and have both sides thickened so that the fenes-
strules are smaller than farther out. The zooecia apertures,
also, are here entirely covered by a minutely granulose second-
ary deposit. Beyond its influence the characters of the zoarium
are as follows: Branches 8 to 10 in 1 cm., moderately
strong and straight, convex and minutely papillose when per-
fect, enlarging from 0.6 mm. just after, to 1.0 or 1.1 mm. just
before a bifurcation. The width of a fully developed branch is
quite uniform at 0.8 mm. Dissepiments rather slender, from
0.3 to 0.5 mm. wide, enlarging at their junction with the
branches. Fenestrules six in 1 cm. varying from subquadrate
to elliptical, about 1.3 by 0.5 mm. Zooecia ranges increasing
from three to six, the usual or normal number being four.
Apertures small, without peristome, arranged alternately, about
fifteen in 5 mm., in the usual state of preservation appearing
oval, but when perfect decidedly pyriform the posterior margin
being sinuate. On the reverse the branches have their summits
narrowly rounded and their sides flattened, giving them a
pinched appearance that is most marked toward the outer
margin of the expansion. The dissepiments occupy nearly the
same plane as the branches and the fenestrules are wider and
more quadrate in form than on the obverse. When very young
they are finely striated, but commonly they are smooth or
covered with extremely minute granules.

This fine species is common and easily recognized by the char-
acters above described.

Position and locality: Keokuk group: numerous localities in
Illinois and Iowa. Warsaw beds, at Warsaw, 111.

POLYPORA MACCOYANA Ulrfch.
PL LIX, figs. 3-3d.

Zoarium a large, flabellate, slowly expanding frond. Branches
six to eight in 1 cm., strong, rigid, subcylindrical, often with a
row of \videly separated and exceptionally large spines, which
usually take the place of a cell aperture. Though varying from
0.6 to 1.2 mm., the average width of the branches is between
0.8 and 0.9 mm. Surface minutely granulose. Dissepiments
slender, rounded, depressed. Fenestrules oblong subquadrate to
elongate-oval, of variable width, averaging 2.4 by 0.8 mm.,

BRYOZOA. 589

with 3 to 3.5 in 1 cm. Zooecia in from four to eight alternat-
ing ranges, normally in five or six. Apertures fourteen or fif-
teen in 5 mm., subcircular, without peristome, appearing larger
in worn examples than in perfect ones, widely separated longi-
tudinally, and arranged in more or less regular intersecting
diagonal series. Reverse of branches and dissepiments convex
and finely striated.

This species, although closely related to P. halliana Prout,
cannot be confounded with it. The fenestrules are so much
longer, the branches stronger, more rigid and cylindrical, that
a glance suffices to distinguish them. P. simulxtrix resembles
it more in its general aspect, but differs widely in important
characters.

Position and locality: Keokuk group. Nauvoo and near
Plymouth in Illinois, and Keokuk and Bentonsport, Iowa.

POLYPORA SIMl'LATRIX Ulrich.
PI. LIX, flg. 4-4b.

Zoarium a large foliate expansion, with strong root-like ap-
pendages at the base. Branches moderately strong, slightly
convex on the poriferous side, rather straight, bifurcating at
long intervals. 0.7 to 1.3 mm. wide. with, generally, seven in 1
cm. Their average width between bifurcations is about 0.8 mm.
Dissepiments one-fourth to one-third the width of the branches,
expanding at their junction with them. Fenestrules 4 to 4.5 in
1 cm., varying from long-oval to sub-quadrangular, with aver-
age dimensions of about 2.0 by 0.6 mm. Zooecia generally in
five or six alternating ranges, twelve or thirteen in each in 5
mm. Apertures comparatively large, circular, surrounded by a
well developed peristome, arranged obliquely across the branches
or in regular diagonally intersecting lines, their diameter or a
little more apart longitudinally. A few small spines, as shown
in fig. 4b, are often present. On the reverse the branches are
strongly rounded, somewhat flattened at the sides, and very
finely striated.

Although in its general aspect this species is very much like
P. maccovana, there are still certain peculiarities which enable
us to separate them easily. The larger number of fenestrules in
a given space alone can be depended upon when the examples

590 PALAEONTOLOGY OF ILLINOIS.

are badly worn, but more perfect ones show more important
differences. The cell apertures in that species are smaller and
without an elevated peristome, and the interspaces between
them crowded with small granules. The branches are also more
convex on the obverse side. The vestibular portion of the
zooecia again is longer, giving the branches a solidity and
strength not possessed by those of P. simulatrix. Hence, while
the branches of the latter are usually flattened by pressure,
those of P. maccoyana, so far as observed, have always retained
their convexity.

Position and locality: Keokuk group. Nauvoo, Warsaw and
Henderson Co., Illinois, and Keokuk and Bentonsport, Iowa.

POLYPORA (?) GRACILI8 PrOUt.

PI. LXI, flgs. 10, lOa.

Polypora gracilis Prout, 1860. Trans. St. Louis Acad. Sei. vol 1, p. 580.
Polypora gracilis Prout, 1866. Geol. Surv. 111. vol. II, p. 422. PI. XXI, flgs. 1, la.

Zoarium a long, narrow, gradually spreading net-work, grow-
ing from a small pedicle. Branches strong, rounded, 0.8 to 1.2
mm. in width, with five or six in 1 cm.; bifurcating at variable
intervals. Dissepiments very thin, slightly expanded at their
junction with the branches. Fenestrules long, quadrangular or
elliptical, usually a little wider than the branches. Their length
varies greatly, the extremes noticed being 3 and 8 mm. Zooe-
cia in from three to five alternating ranges. Apertures small,
circular, pustuloid when perfect, widely separated longitudinally,
about nine in 5 mm. The branches are covered with granulose
striae, and on old examples there is a row of strong spines along
the center of the branch. Reverse convex, smooth or finely
striated.

In its growth this species approaches Thamniscus, but in its
minute characters it closely resembles such species of Polypora
as P. maccoyana and P. halliana.

Position and locality: Keokuk group. Warsaw and Nauvoo,
Illinois, Keokuk, Iowa, and King's Mountain, Ky.

BRYOZOA. 591

POLYPORA RETRORSA Ulrich.
PI. LIX, flgs. 6-6d.

Zoarium a small, rapidly expanding, foliar net-work. Branches
6.5 to 7 in 5 mm., rounded, slender, averaging 0.4 mm. in
width, but increasing from 0.3 to 0.5 or 0.6 mm. before bifurca-
tion takes place. Dissepiments short, depressed, half as wide
as the branches. Fenestrules long-oval or sub-quadrangular,
five or six in 5 mm., narrower than the branches. Zocecia in
three or four alternating ranges, in each about twenty in 5
mm. Apertures small, sub-oval, seemingly directed backward
on account of the peristome, which is much the highest on the
anterior side; sometimes with a rayed appearance. On the re-
verse the branches and dissepiments are rounded, occupy the
same plane, are nearly of the same thickness, and exhibit nu-
merous distinct granules, arranged in one or two encircling
series. The fenestrules are shorter than on the obverse, and
regularly elliptical in form.

The distinct granules and rounded fenestrules of the reverse,
and the unequally developed peristome separate this species
from, at any rate all the Carboniferous species of the genus,
known to me.

Position and locality: Keokuk group. Rather rare at Keo-
kuk, Iowa.

POLYPORA RADIALIS Ulrich.

PI. LX, flgs. l-ld.

Zoarium very small, compact, two or three cm. in diameter,
originally flabellate, but by expanding very rapidly the lateral
margins at last meet and unite, giving it the appearance of a
very much depressed funnel. Branches comparatively strong,
close together, 0.3 to 0.5 mm. wide, and eight or nine in 5 mm.,
their surface minutely granulose. Dissepiments short, depressed,
varying from one-fourth to two-thirds the width of the branches,
their width depending largely upon the relative proximity of
neighboring branches, being widest when these are nearest.
Fenestrules small, irregular, sub-oval, about 0.5 by 0.2 mm.,
and between six and seven in 5 mm. Zocecia in two ranges im-

592 PALAEONTOLOGY OF ILLINOIS.

mediately after bifurcation, these soon increase to three, and
then to four before the next division. Apertures circular, rayed, •
with prominent peristome, less than twice their diameter apart,
about twelve in 3 mm. On the reverse the branches are rather
straight, the dissepiments half as wide, the fenestrules sub-
quadrate or elliptical, and twice as long as wide.

This beautiful little species is distinguished from its nearest
relative P. retrorsa, by its closer branches, smaller fenestrules,
their more elongate form, smooth and straighter branches on
the reverse, and the direct apertures. The rayed apertures are
also better shown in P. radialis than in any other species of
the genus known to me.

Position and locality: Keokuk group. Rare at Keokuk, Iowa.

POLYPOKA BISERIATA UMch.

PI. LX, figs. 4-46.

Zoarium a slowly expanding, irregular, more or less undulat-
ing, foliar net-work, from four to eight cms. in height. Branches
closely approximated, seventeen to nineteen in 1 cm., slender,
averaging 0.5 mm. in width, but increasing from 0.4 to < .7
mm. before bifurcation, which takes place at intervals of from
5 to 14 mm. Their poriferous surface is nearly flat or slightly
elevated centrally, where a row of prominent spines or nodes,
about 0.45 mm. apart, almost gives the impression of a median
keel. Dissepiments short, depressed, one-half or less than one-
half the width of the branches. Fenestrules small, sub-oval,
about fourteen in 1 cm. Zooecia in two alternating ranges, in-
creasing to three at a point 2 or 3 mm. below the branch di-
visions. Apertures large, 0.15 mm. in diameter, direct, with
prominent peristome, seventeen or eighteen in 5 mm., their di-
ameter or less apart, often closed by an opercular cover of the
usual type. On the reverse the branches are rather broadly
rounded, somewhat channeled below the bifurcations, and either
smooth or very finely striated; the dissepiments thin and not
depressed, and the fenestrules sub-quadrate.

The material upon which this species is founded is very satis-
factory, many of the examples being free and in a fine state of
preservation. The species is very constant and all the speci-

BRYOZOA. 593

mens, save one, agree closely in their measurements. The latter
adheres to the rock and exposes the obverse side. So far as
can be seen it agrees with the typical form in every respect ex-
cepting that the fenestrules are larger, there being only ten in
1 cm. It probably represents a variety.

The affinities of the species lie with P. varsoviensis Prout.
That form is larger, has invariably one row of cells more to
the branch, and larger fenestrules.

Position and locality: Warsaw beds. Monroe Co., 111., and
Warsaw, 111. The same or a closely allied species occurs in the
St. Louis limestone at Barrett's Station, Mo.

POLYPORA VARSOVIENSIS Prout.

PI. LX, figs. 2-2b.

Polypora varsoviensis Prout, 1859. Trans. St. Louis Acad. Sci. Vol. 1, p. 236. PI. 15,
flg. 3-3b.

Zoarium a large irregular foliar expansion. Branches rather
strong, rounded, nine to eleven in 1 cm., averaging 0.7 or 0.8
mm. in width, but increasing from 0.5 to 0.9 or 1.0 mm. be-
fore bifurcation takes place. Dissepiments short, slender, be-
tween 0.2 and 0.3 mm. thick. Fenestrules oval, somewhat ir-
regular in size and shape, averaging 0.9 by 0.4 mm., with from
6 to 8.5 in 1 cm., the most common number being 7.5. Zooecia
at first in three alternating ranges, then in four, and, just be-
fore the branch again divides, in five. Apertures large, with a
prominent peristome, their diameter or less apart, with fourteen
or fifteen in 5 mm. On the reverse the branches are broadly
rounded, smooth or finely striated, the dissepiments thin, the
fenestrules nearly regularly elliptical, or occasionally, approach-
ing subquadrangular, with their length fully equal to twice the
width.

The larger dimensions of the fronds of this species distinguish
them from P. biseriata. The two are almost constantly asso-
ciated, and in both the zooecia apertures are larger than usual.
P. simulatrix of the Keokuk group agrees with them in this
respect, but differs in having stronger branches and consider-
ably larger fenestrules.
—74

594 PALAEONTOLOGY OF ILLINOIS.

Position and locality: Warsaw beds. Abundant at Warsaw,
Illinois, and Monroe Co., Illinois; also in the St. Louis lime-
stone at Barrett's Station, St. Louis Co., Mo.

POLYPORA SPININODATA Ulrich.

PL LX, fig. 3.

Of this species I have only seen one large semi-circular frond
in good preservation, and a smaller weather-worn fragment.
Unfortunately both adhere firmly to the rock so that the re-
verse only can be seen. With the aid of thin sections the
ranges of zooecia have been determined. The characters of the
reverse are as follows: Branches rather slender, varying from
0.3 to 0.6 or 0.7 mm., with thirteen to fifteen in 1 cm., bifur-
cating at long intervals. Their surface is strongly rounded,
covered with distinct longitudinal striations, and raised, at in-
tervals about equal to the length of a fenestrule, into pro-
nounced spines or nodes. Dissepiments generally less than half
the width of the branches, slightly depressed or on a level with
the branches, subcarinate or narrowly rounded. Fenestrules
elliptical, nine or ten in 1 cm., averaging 0.7 by 0.35 mm.
Zooecia at first in two ranges, then in three, and later on in
four. The last number prevails for from 1 to 3 mm. before the
branch divides.

The strong hollow nodes on the reverse of the branches, dis-
tinguish this species from all Carboniferous species of Polypora
known to me. In the proportions and number of zooecia the
species occupies an intermediate portion between P. biseriata
and P. varsoviensis. Thin sections also show some slight dif-
ferences in their minute structure.

Position and locality: Warsaw beds, at Warsaw, 111.

POLYPORA CESTRIENSIS Dlrich.

PI. LV, figs. 4-4b, and PL LX, flgs. 7-7c.

Zoaria consisting of foliar expansions of somewhat lax and
irregular growth. Branches rather strong, slightly rounded,
with a row of faint nodes along the center about 0.5 mm,
apart; width above a bifurcation 0.5 mm., increasing to 1.0
mm., with about eight in 1 cm. Dissepiments slender, slightly

BRYOZOA. 595

depressed and expanded at each end, from 0.25 to 0.4 mm.
thick; in some specimens with parallel striae extending from
branch to branch. Fenestrules rather large, narrow, sub-oval,
with slightly indented margins, five or six in 1 cm., their aver-
age dimensions being 1.5 by 0.5 mm. Ranges of apertures
alternating, increasing from three to four (the number imme-
diately after bifurcation) to six just before the next division.
Very young examples have the ranges of apertures separated
by fine tortuous lines which become obsolete with age. Ordi-
narily the apertures are small, circular, pustuliform, generally
about twice their diameter apart, with seventeen in 5 mm. On
the reverse the branches are strongly convex, smooth, or with
exceedingly fine longitudinal striae. The fenestrules are wider
and appear more nearly quadrangular than on the opposite
face.

This easily recognized species is one of the most common and
characteristic fossils of the Chester group. Its fronds are
larger in every way than those of its nearest congener P. tuber-
culata Prout, while the pustiliforni cell mouths and lax growth
separate them from Keokuk and Warsaw species.

Position and locality: Chester group, at Chester, Kaskaskia.
near Anna, and other localities in Illinois; also at Litchfield
and Sloan's Valley. Ky.

POLYPORA TUBERCULATA Pl'OUt.

PI. LX, fig. 8.

Polypora tuberculata Prout, 1859. Trans. St. Louis Acad. ScL.Vol. 1, p. 449. fig.3, pi. 18.
Not Polypora tuberculata Nich., 1874. Pal. Ontario, p. 110, fig. 37.

Zoarium a small, flabellate net-work, not known to exceed
•'"5.5 cm. in height. Branches twelve to fourteen in 1 cm., sub-
cylindrical, slender, with an average width of 0.45 mm., but
enlarging from about 0.3 to 0.6 mm, before bifurcation, which
takes place at intervals varying from 1.5 to 8.0 or more mm.
Along the middle of the branches there is an irregular row of
moderately prominent and widely separated nodes, with only
one or two in the length of a fenestrule. Dissepiments some-
what depressed, one-third to one-half the width of the branches.
Fenestrules suboval but variable in size and shape, with aver-
age dimensions of 0.7 by 0.35 mm., and eight or nine in 1 cm.

596 PALEONTOLOGY OF ILLINOIS.

Zooecia normally in three or four, somewhat irregular, alterna-
ting ranges, just before bifurcation in five or six, and immedi-
ately after, rarely in two, generally in three. Apertures small,
circular, when perfect somewhat pustuloid, about twenty-five in 5
mm. On the reverse the branches are rather narrowly rounded,
slightly zigzag, and smooth or finely striated; the dissepiments
scarcely depressed, and a little wider than on the opposite face;
the fenestrules about as wide as the branches, and of oblong
subquadrangular or subovate form. A few root-like apendages
spring from the branches near the base, and occasionally fap-
ther up on the frond.

This species is on the order of, but in every way smaller than
P. cestriensis. It has been erroneously identified in the Scotch
Carboniferous shales by Mr. John Young. Mr. G. R. Vine,*
after noting the resemblances and differences comes to the same
conclusion, although his American examples of the species, are,
as I have good reason to know, really quite different from
Front's P. tuberculata, and probably belong to P. spinulifera
of this work. The slightly raised keel which Prout says separ-
ates the rows of cells in this species I have never seen, nor
are the tuberculations so numerous as stated by him. These
characters he probably obtained through confounding a frag-
ment of P. cestriensis with the true P. tuberculata. His fig-
ure is quite reliable and shows the tubercles as above described,
but no lines between the rows of cells. The dissepiments are
represented a little too thin.

Position and locality: Chester group. Not uncommon at
Chester, 111.; rare at Litchfield, Ky.

POLYPORA CORTICOSA UMch.

PL LX, Figs. 5-5c, and PL LXI, Fig. 1.

Zoarium rather small, forming a flattened expansion, perhaps
not exceeding three or four cm. in height, which springs from
a strong, solid, finely striated foot-stalk. Both surfaces of the
branches near the base are covered with the striated deposit,
causing the fenestrules to become very small or entirely filled

* Notes on Yoredale Polyzoa, 1886, p. 17.

BRYOZOA. 597

up. Beyond its influence the characters are as follows: Branches
strong, broadly convex, eight or nine in 1 cm. with an average
width of 0.8 mm., but increasing from about O.G mm. imme-
diately after bifurcation to about 1.1 mm. before again dividing.
Dissepiments short, slightly depressed, gradually decreasing in
width from the base toward the free margin, where their width
varies from 0.4 to 0.6 mm. Fenestrules comparatively small,
oval, increasing in width outward, with 6 or 6.5 in 1 cm.
Zooecia at first in four alternating ranges, then in five, six, and
seven rows (occasionally in eight) before the branch divides.
Apertures about twenty in 5 mm., small, circular, with faint
peristome, their diameter or more apart longitudinally, the
rows separated by a fine wavy line that is alternately stronger
and weaker and occasionally sufficiently elevated to form a
small node or spine. On the reverse the branches and dissepi-
ments are strongly rounded, upon the same plane, of nearly
equal thickness, and finely striated. The branches being thinner
than on the opposite face causes the fenestrules to be larger,
their average dimensions being about 0.8 by 0.6 mm. Their
form is somewhat variable, but, as a rule, they are broad-oval.

The seemingly disproportionate strength of the zoarium, and
the striated solid tissue which is drawn over the basal portion
of both sides, give this species a decidedly distinct appearance.
In many respects the species resembles P. complanata, but that
form is larger, more regular, has the zooecia open down to the
foot-stalk, the branches less convex and more uniform, the
feuestrules smaller and circular, and no striations between the
zooecia apertures.

Position and locality: Chester group, Chester, 111.

POLYPORA COMPLANATA UMch.
PL LX, Fig. 6-6c.

The above name is proposed for the specimen figured and one
other. A number of fragments now before me may represent
young examples of the same species but as their general appear-
ance is more like that of P. corticosa. and, as none of them
expand as rapidly as the types, I prefer to leave them unclassi-
fied for the present. The types which expose only the obverse
side may be described as follows: Zoarium a semi-circular and

598 PALEONTOLOGY OF ILLINOIS.

slightly concave foliar expansion, 4 cm. wide and nearly 3
cm. high, growing from a short foot-stalk, with the branches
scarcely distinguishable, the whole appearing rather as a ryth-
mically perforated plate. Branches flat, bifurcating frequently
and rapidly increasing in width from 0.7 to 1.5 mm. Dissepi-
ments depressed, very short, extremely wide, the width equal to
that of the branches and two or three times their length. Fenes-
trules circular, or nearly so, 0.3 to 0.5 mm. in diameter, with
seven in 1 cm. Zocecia in rather irregular ranges increasing in
number from three or four to eight or nine between the bifurca-
tions. Apertures nineteen or twenty in 5 mm., small, circular,
when perfect with a faint peristome. Interspaces wider than the
apertures, apparently set with inconspicuous nodes. From thin
sections it appears that the reverse side of the branches is
broadly rounded, and the dissepiments much depressed.

The examples from which the above description is drawn differ
so much from the ordinary species of the genus that I do not
hesitate in proposing a new name for them. The relation of
the species to P. corticosa can only be determined by more
complete examples than have as yet fallen under my notice.

Position and locality: Chester group, Chester, 111.

POLYPORA SPINULJFERA Ulrich.
PL LXI, Fig. 2-2a, 3-3a, 4-4a.

Zoarium a foliar, fan shaped, undulated or flat, expansion 4
or 5 cms. in height. Branches rather slender, gently convex,
about thirteen in 1 cm., and from 0.5 to 0.8 mm. in width.
Surface spinulose, the spines small, about two-thirds as numer-
ous as the zooecia, and irregularly distributed. Dissepiments
short, rounded, depressed, from one-third to one-half as wide as
the branches. Fenestrules irregularly oval, more or less in-
dented, 9.5 to 11 in 1 cm.; on an average 0.6 by 0.3 mm.
Zooecia in from three to five alternating ranges, these numbers
being the extremes between the bifurcations. The prevailing
number is four. Apertures small, with well developed peristome,
twenty to twenty-one in 5 mm., regularly arranged between the
small tubercles. On the reverse the dissepiments are about as
wide as the branches, and both are strongly convex and smooth,
while the fenestrules are regularly broad-oval or subcircular,

BRYOZOA. 509

they and the dissepiments being wider and the branches nar-
rower than on the obverse side.

A variety of this species is represented by figs. 3 and 3a. It
is from the Coal Measures in Montgomery Co., 111., and differs
from the typical form in having three as the prevailing number
of zooecia ranges, narrower branches, and wider, subquadrangu-
lar fenestrules. The zocecia are also a little larger, there being
only eighteen or nineteen in 5 mm. The form represented by
figs. 4 and 4a, is also from the Coal Measures. It agrees more
closely with the typical form, differing mainly in having the
fenestrules slightly shorter and the dissepiments correspondingly
stronger. In the number of cell rows it is intermediate between
the Chester form and the Montgomery Co. variety.

Position and locality: Chester group, Chester, 111., and Mon-
roe Co., 111. Coal Measures, Montgomery Co., 111., and near Red
Oak, Iowa.

POLYPORA APPROXIMATA Ulrich.

PI. LXI, Figs. 5-5a.

Polypora biarmica Prout, (non Keyserling) 1859. Trans. St. Louis Acad. Sci., vol. 1,
p. 450.

This is probably only a well marked variety of P. spinulifera,,
but it is sufficiently distinct to deserve a name. It differs in
the following respects: The zoarium is stronger and in every
way presents a more robust aspect, the branches and dissepi-
ments being somewhat wider, and the fenestrules larger, espe-
cially upon the reverse side. There are seven to nine fenestrules
instead of ten or eleven. The number of cell ranges increases
quite regularly from three or four just after a bifurcation, to
six or seven before the next division. The nodes or spines are
stronger, much less in number, and generally occupy only
the center of the branches.*

Position and locality: Chester group, Chester, 111.; Sloan's
Valley and Litchfield, Ky.

*I have lately collected several hundred examples of this species, showing it to be a
constant form and qui e distinct from P. spinulifera. The specimens were obtained
from near Clayton P. O., Caldwell Co., Ky., where they occurred in a bed of shaly
limestone at the top of the Chester.

600 PALAEONTOLOGY OF ILLINOIS.

POLYPORA WHITEI Ulrich.

PI. LXII. Fig. 2.

Zoarium a delicate, slowly expanding, foliar net-work, branches
very slender, rigid, varying from 0.25 to 0.5 mm. wide, w-ith
nine or ten in 5 mm. Dissepiments slender, about 0.1 mm.
thick, enlarging at each end. Fenestrules subovate, nearly as
wide as the branches, 0.7 by 0.25 mm. their average dimen-
sions, with six in 5 mm. Zooecia in two and three rows except-
ing just below a bifurcation where a fourth is interpolated.
The ranges are separated by an interrupted or continuous
keel, which gives the branches so long as they have only
two ranges of cells, very much the appearance of a Fenestella.
At intervals the keel is slightly elevated so as to form a small
node. Apertures circular or faintly truncated at the posterior
side, with a thin peristome, about nineteen in 5 mm. The
longitudinal spaces between the apertures are equal to nearly
twice their diameter, and usually marked by two or three raised
lines. Reverse not seen.

In this species we see, perhaps, the last of the numerous links
between Fenestella and Polypora. Such species have been de-
scribed from the Niagara and all the principal horizons between
that and the Hamilton group, but have not, heretofore, been
known from Carboniferous deposits.

It gives me much pleasure to name this beautiful species for
my esteemed and distinguished friend, Dr. Charles A. White, of
Washington, D. C.

Position and locality: Base of Coal Measures, Seville, 111.

POLYPORA WHITEI var. INSCULPTA ri. var.

PI. LXII, fig. 1.

This variety or species closely resembles the type of P. eximia
but differs in the following points. The branches are slightly
wider, less rigid, the two ranges of zocecia sooner give way to
three and these to four, the separating ridges are more irregu-
lar, the finer lines wanting, the peristomes more elevated and
thicker, and the fenestrules larger, there being only 4.5 in 5
mm.

Position and locality: Upper Coal Measures, at Springfield,
Illinois.

BRYOZOA. 601

POLYPORA XODOCARIXATA Ulrich.
PI. LXI, fig. 9-fla.

Zoariuru infundibuliform, large, thrown into strong folds to-
ward the tipper margin, poriferous on the inner side. Branches
moderately strong, rigid, averaging ten to 1 cm., 0.5 or 0.6
mm. wide at a point immediately above a bifurcation; the width
gradually increases to 0.7 mm., which prevails till a short dis-
below the next bifurcation when another 0.1 mm. is added
The bifurcations being widely separated,' the increase is very
gradual. Dissepiments short, depressed, rounded, 0.3 or 0.4
mm. wide. Fenestrules oval or subquadrangular, about 0.7 by
'0.3 mm., and 8.5 or 9 in 1 cm. Zooecia in four regular alter-
nating ranges, excepting for a short distance after bifurcation
where three is the prevailing number-, and occasionally just be-
fore bifurcation where a fifth row may be developed. Apertures
circular, without a peristome, about their diameter apart, nine-
teen in 5 mm. The ranges of apertures are separated by three
rows of tubercles, of which the central row is much the most
conspicuous, giving the branch the nodo-carinate appearance
that has suggested the name. Frequently, however, the tubercles
occupy the longitudinal spaces between the cell apertures when
that appearance is less marked. On the reverse the branches
are narrowly rounded and appear very thin, the fenestrules are
larger, averaging 0. 8. by 0.7 mm., nearly square! or slightly
hexagonal. The surface of the branches is smooth over the
lower half of the zoarium, and finely striate toward the upper
margin.

The subcarinate branches, with their four ranges of apertures
bring to mind F"enextr<ilm sxnc-ti-ludovici Prout. This character,
and the nearly square form of the feuestrules on the reverse,
distinguish the species from all Carboniferous Polyporse known
to me.

Position and locality: Upper Coal Measures; Crooked Creek,
near Ceutralia. 111.; also in Macoupin Co.

—75

602 PALEONTOLOGY OF ILLINOIS.

POLYPORA SUBMARGINATA Meek.

PI. LXI. flg. 6-6b.

Polypora marginata Geinitz, 1866. Garb. u. Dyas in Neb. p. 69, PL 5, figs, 11, a, b,
and 12 a, b. (not McCoy. 1844, Syn. Carb. Foss. Ireland p. 206, PL 29, flg. 5.)
Polypora submarginata Meek, 1871. Pal. E. Neb. p. 154, PL 7, flgs. 7a, 7b.

Zoarium flabelliform, probably not exceeding three or four
cm. in height. Branches about seven in 1 cm., sub-pentagonal
in cross section, with the obverse side strongly convex, subcar-
inate when typical, and carrying a row of small, conical, rather
prominent spines or tubercles along the middle, about 0.3 mm.
apart; the two lateral margins sharply angular. The average
width of the branches is about 0.7 mm., but gradually increases
from 0.5 mm. to 1.0 mm. between the bifurcations. Dissepi-
ments rather long, slender, 0.3 to 0.5 mm. wide, spreading
slightly at each end, faintly striated or smooth, narrowly
rounded. Fenestrules oblong oval to subquadrangular, about
as wide as the branches, twice as long, averaging 1.7 by 0.8
mm., and 4 to 4.5 in 1 cm. Zocecia five or six to the fenestrule
generally in five ranges, which number may be increased to six
just before bifurcation. Immediately after, but only for a short
distance, there are only three or four ranges. Apertures circu-
lar, 0.11 mm. in diameter, nearly twice their diameter apart
longitudinally, about fifteen in 5 mm., rather irregularly ar-
ranged, with a well developed but not strong peristome. In a
normal development the apertures of the central range alter-
nate with the tubercles. On the reverse the branches are nar-
rowly rounded, flattened on the sides, and smooth or finely
striated. Near the base they are irregular, the dissepiments
nearly as strong and on a level with the branches. The fenes-
trules are large, oblong subquadrate, or irregular.

This distinct and common species is very characteristic of the
Upper Coal Measures of the western states. It is on the order
of, but much larger than the P. nodocariiiata. Associated with
it in Illinois, I have met with a smaller species having no
tubercles and 5.5 fenestrules to 1 cm. The. latter also occurs
in the Lower Coal Measures, from which I have obtained good
specimens. These have fine waving ridges between the rows of
cell apertures, agreeing in this and other respects rather closely
with McCoy's P. marginata.

BRYOZOA. 603

Position and locality: Upper Coal Measures, Macoupin Co.,
Illinois, LaSalle and Springfield, Illinois, near Red Oak, Iowa.
Nebraska City, Neb., and other localities.

POLYPORA DISTINCTA UMch.
PI. LXI, flg. 7-7a.

Zoariuni a foliar expansion of unknown dimensions, forming
a loose net-work. Branches rather strong, not rigid, moder-
ately convex, 0.7 to 1.4 mm. wide, about five in 6.5 mm. Dis-
sepiments short, depressed, varying in width from 0.4 to 0.7
mm. Fenestrules usually a little narrower than the branches,
varying greatly in length, the extremes noticed being 2.7 and
4.5 mm., but most of them vary between 3.5 and 4.0 mm.,
while the average width may be put down at about 0.6 mm.
Zooecia in from four to six ranges. These are increased to seven
or eight just before bifurcation. Apertures subcircular, often
slightly sinuate at the lower margin, arranged in rather regular
diagonally intersecting series, in which five occupy a space
about 1.4 mm. long; longitudinally thirteen or fourteen OT^cur
in 5 mm. Peristome moderately strong, but wanting at the
lower side, causing the apertures to appear slightly oblique.
Interspaces wide, with an occasional node, and when well pre-
served, minutely granulose. Reverse strongly rounded, finely
striated or smooth.

The long fenestrules and general appearance of the zoarium
suggests a relationship to P. gracilis and P. maccoyana of the
Keokuk group. The incomplete peristome, more crowded zooe-
cia, and less convex branches, distinguish it from the first,
while the greater length of the fenestrules, less rigid branches
and other differences, separate it from the second. P. grandis
Toula, and P. gigantea Waagen and Pichl, are larger in every
respect.

Position and locality: Upper Coal Measures; Springfield, 111.

*
POLYPORA CRASSA (Provisional.)

PI. LXI, flg. 8-80.

Zoarium a rapidly expanding flat net-work, 4 cms. in width.
Branches strong, broadly convex, bifurcating frequently, five to

604 PALAEONTOLOGY OF ILLINOIS.

six and one-half in 1 cm., and from 0.9 to 1.3 mm. in width.
Dissepiments of variable width. Fenestrules oblong oval, gen-
erally a little narrower than the branches, and three or four
times longer than wide, usually 2.4 by 0.7 mm. and 3.5 in 1
cm. Zooecia in from five to eight ranges. Apertures circular,
arranged in more or less regular diagonally intersecting series,
in which four occur .in the space of 1 mm. Longitudinally
about eleven in 3 mm. The zooecia apertures usually do not
extend to the margin of the branches.

The specimen for which the above name is provisionally pro-
posed, is not sufficiently preserved to render its specific deter-
mination satisfactory. It is proportionately larger than P. cor-
ticosa. The P. koninckiana, lately described by Waagen and
Pichl from the Permo-carboniferous deposits of India, agrees in
many respects, but I do not believe them identical. Better speci-
mens of the American form are necessary before its affinities
can be ascertained.

Position and locality: Upper Coal Measures, Sugar Creek,
Sangamon county, Illinois.

FENESTRALIA Prout, 1859.

(Trans. St. Louis Acad. Sci. Vol. I, p. 235.)
(For generic diagnosis see page 396.) «

The validity of this genus is provisionally admitted because
of the importance of the carina among the FEXESTELLID.E. Be-
yond this feature, F. sancti-ludovici differs in no respect from
Polypora, unless we credit the fact that the rows of cells are
constantly four, with generic importance.

FENESTRALIA SANCTI-LUDOVICI Prout.

PL LV, fig. 5.

Fenestralia St. Ludovici Prout, 1859. Trans. St. Louis Acad. Nat. Sci. Vol. I, p.
235, PL 15, figs. 1-la.

Zoarium a large flabelliform expansion. Branches 9.5 to 11.5
in 1 cm., rather slender and unequal, somewhat rigid, strongly
carinated, the aperture bearing surfaces either flat or slightly
convex; average width of branches 0.6 mm., increasing from

BRYOZOA. 605

0.5 to 0.7 or 0.8 mm. between the bifurcations. Dissepiments
rounded, depressed, expanding but little at their ends, about
two-thirds the width of the branches. Fenestrules oblong sub-
quadrangular or oval, their width varying from one-fourth to
one-half the length; about six in 1 cm. longitudinally. Carina
strong, rounded, dilating into prominent elongated tubercles at
intervals of 1 mm. Zooecia in four ranges, two on each side of
the carina. Apertures sometimes alternating, usually opposite,
those of the lower ranges opening obliquely or directly into
the fenestrules and often obscured by those of the upper rows.
When the matrix completely fills the fenestrules the lower rows
are not seen and the specimens might be mistaken for Fenes-
telki. There are six or seven apertures in each row to a fenes-
trule. one of them opposite each dissepiment. The apertures
are of medium size, surrounded by a thin peristome, their dia-
meter or a little more apart, with eighteen in 5 mm.

On the reverse the branches are narrowly rounded, smooth or
finely granulose, have sloping sides, are straight or slightly zig-
;ind appear much thicker than on the opposite side. The
dissepiments are straight, nearly as strong as the branches,
and but little if at all depressed. The fenestrules vary consider-
ably in width, but are always wider than the branches, and
once and a half or twice as wide as on the obverse face. In
form they vary from quadrangular to hexagonal.

The above .describes the typical form as it is found in the St.
Louis limestone at Alton, Illinois, and St. Louis. Mo. Prout's
figures are faulty in having the dissepiments as high as the
branches when they are really depressed. In the Warsaw beds
i variety that appears to agree in every respect except-
ing that its branches are invariably somewhat thinner. A more
distinct variety or species differs as follows:

var. COMPACTA n. var.

PI. LIX, Fig. 1.

The branches are as a rule a little thinner and closer together
there being 11.5 to 12.5 in 1 cm.: the nodes on the keel incon-
spicuous or wanting, but large nodes often occur on the reverse.
The dissepiments depressed, rather strong and rounded, the

606 PALEONTOLOGY OF ILLINOIS.

fenestrules oval, nearly or quite as wide as the branches, eight
in 1 cm. The zooecia have prominent mouths, with twenty or
twenty-one in 5 mm. The variety thus appears to be more
compact in every way than the typical form.

Position and locality: St. Louis group and Warsaw beds. St.
Louis and Barrett's Station, Mo. Alton, Columbia, Warsaw
and localities in Monroe Co., 111. The variety is from Elizabeth-
town, Ky., where it was found associated with typical St. Louis
fossils.

THAMNISCUS King, 1849.

(Ann. & Mag. Nat. Hist. 2d ser., Vol. III. p. 389.)
(For generic diagnosis, see page 397.)

This genus was founded by King upon the Permian fossil
Keratophytes dubius Schlotheim. It also seems evident that
King intended to include Silurian and other forms as well, but
to arrive at a true and conclusive idea of the genus the char-
acters of the type species alone can be depended upon.

King's description of T. dubius has been shown to the errone-
ous in several important respects by Mr. G. W. Shrubsole.*
He shows that the supposed "gemmuliferous vehicles," only re-
present the broken or worn hollow spines, and that the zooecia
apertures are provided with an elevated peristome. These ob-
servations I can verify, having lately studied a series of German
specimens which were procured for the purpose. I find, further,
that the poriferous face of the branches is in every essential
respect identical with that of such species of Polypora as P.
cestriensis and P. spinulifera. Some of my own specimens
being in a good state of preservation show the nodes or spines
and the peristomes very well, and that the latter are especially
prominent about the apertures of the marginal zooecia,. The
nodes are numerous and occur on two or three faint longitudi-
nal lines which run between the ranges of apertures. Another
character that aids in linking the genus to Polypora is shown
by the two specimens figured on plate 62. There is an occa-
sional dissepiment, which unites the branches when, after bifur-

* Quart. Jour. Geol. Soc. for Aug., 1882, p. 341.

BEYOZOA. 607

cation, they are brought close together. Though developed less
numerously and shorter than they are in T. ramulosus and
divaricans, it is now evident that the total absence of dissepi-
ments can no longer be insisted upon as one of the distinguish-
ing features of Thamniscvs, but we must fall back upon the
frequent dichotomization of the branches as the only remaining
diagnostic character. Of course the relative paucity of the dis-
sepiments aid very materially in separating species of the
genus from those of Polypora, yet a sharp divisional line be-
tween these two groups is out of the question. In fact, I think
that a very nearly complete line of development can be shown
between T. dubius and Polypora in which P. dendroides (McCoy)
P. gracilis (Prout) T. divaricans and T. ramulosus would figure
prominently. The question, what about the Silurian and De-
vonian species which have been placed under Thamniscus? ', I
cannot enter into at present, beyond the simple expression of
my belief that none of them belong to the special line of devel*
opinent that culminated in T. dubius, unless, perchance, we
agree that the tendency to deviate in that direction was re-
tained by certain forms which may have reverted to the parent
branch, and only required the proper condition to again assert
itself. It does not, however, seem at all probable that all of
them were subjected to this possible reversion, since in T. sculp-
tilis and T. octonarius, we have two species that are most
probably descendants of the more ancient line. Some of the
Devonian species complicate the geneological problem by pre-
senting marked external resemblances to Idmonea, but how far
the agreement may be the result of true relationship remains
to be determined.

For the present we my say that Thamniscus, as now under-
stood, commences in the Niagara with one species,* is repre-
sented by two species in the Lower Helderberg, continues through
the various Devonian and Carboniferous groups, and culminates
in the Permian formation. Neither the species, of which the
total number is about sixteen, nor the individuals seem at any
time to have been abundant.

* Hall's T. niagarensis belongs to my new genus Drymotrypa. but his Hornera?
dichotoma, is closely allied to the Wenlock Thamniscus crassus Lonsdale sp.

608 PALEONTOLOGY OF ILLINOIS.

THAMNISCUS DIVARICANS Ulrich.

PI. LXII, fig. 6-Cc.

Zoarium consisting of rather stout, remotely bifurcating
branches spread in a plane. The bifurcations, though terminal,
usually seem all to spring from one side of a primary branch,
giving the zoariurn the appearance of unilateral development.
The branches are more or less nearly parallel, and, whenever
they are brought into close proximity, are united to each other
by thin dissepiments. On the reverse they are rather strongly
rounded and covered with very fine longitudinal striae; on the ob-
verse, slightly convex, 1.0 to 1.5 mm. in width, with dentate mar-
gins due to the lateral projection of the marginal ranges of
zocecia mouths. Zocecia in from five to seven ranges. Aper-
tures sub-circular, about 0.1 mm. in diameter, arranged in
parallel elevated series curving outward and upward from the
center to each margin of a branch very similar to the arrange-
ment in certain species of Idmonea,. About eight of the V -shaped
series occur in the length of 5 mm. The apertures really occupy
the summits of ridges which increase considerably in height to-
ward the margins of the branches. The transverse spaces be-
tween the apertures are more or less depressed, but not nearly
so much as the spaces which separate the ridges. When per-
fectly preserved, all the interspaces are finely granulo-striate,
the striations having a longitudinal direction.

This is an unequivocal species of Tlmmniscus, and somewhat
resembles the T. serialis Waagen and Pichl, from the Upper Car-
boniferous rocks of India. It also resembles the associated
Polypora? gracilis Prout, especially when the branches are
united by unusually numerous dissepiments, as in the example
represented by fig. 6b.

Position and locality: Keokuk group, King's Mountain, Ky.

THAMNISCUS SCULPTILIS Ulrich.

PL LXII, fig. 8, 8b.

Zoarium small, consisting of slender, subcylindrical branches,
from 0.4 to 0.8 mm. in width, which bifurcate two or three
times at intervals varying from 3 to 4 mm. Angle of bifurca-

BKYOZOA. 609

tion very wide, usually about 90°. Zooecia small, in from five
to nine ranges. About two-thirds the circumference of the
branches is taken up by their apertures, the remaining third
being non-celluliferous, and smooth or very finely striated. On
the obverse face of the widest examples the zocecia apertures
are arranged in oblique curved series very much as in T. divan-
cans (PI. 62, fig. 6a). The series, however, are much closer
together, there being ten in 3 mm., the apertures smaller (about
0.07 mm. in diameter,) less pronounced, and surrounded by a
thin peristome. The central rows especially are also arranged,
in longitudinal series between distinct elevated lines, causing the
formation of a deeply concave oblong space behind each aper-
ture. As intimated, this concave space becomes gradually less
distinct on the sides of a branch, and disappears entirely before
reaching the irregular rows that margin the non-celluliferous
space. In narrow or young examples the arrangement is as
shown in fig. 8a.

This species is peculiar in the wide angle at which the branches
bifurcate, the depressed space behind the zocecia apertures, the
small size of the zooecia. the subcylindrical form of the branches,
and the narrow non-poriferous space. These features distinguish
it from all the species of the genus known to me.

Position and locality: Keokuk group, King's Mountain, Ky.

THAMNISCUS FUBCILLATUS Ulrich.

PI. LXH, fig. 9,9b.

Zoarium small, consisting of slender, dichotomously divided
branches, increasing very gradually from 0.5 to 0.6 or 0.7 mm.,
between the bifurcations. Bifurcations terminal, widely sepa-
rated, rarely less than 7 mm. apart, but varying between the
extremes of 4 and 9 mm. Angle of bifurcation between 60° and
90°. Zooecia usually in four ranges; in three or four just after,
and four or five just before bifurcations. Apertures small, sub-
circular, 0.08 mm. in diameter, about seventeen in 5 mm., with
a peristome, alternating in adjoining rows, the rows separated
by more or less continuous elevated lines, which often carry
small nodes. The nodes, however, are never conspicuous. Both
—76

610 PALEONTOLOGY OF ILLINOIS.

surfaces moderately convex, the width of a branch being greater
than its thickness. When well preserved the reverse side is
finely striated.

This is one of the most characteristic species of the Chester
group, being moderately abundant at all of the typical locali-
ties where the horizon is exposed. It is also very distinct from
all the American forms, the principal peculiarities being the four
ranges of zooecia and the slender branches. A similar species is
described by Mr. G. R. Vine from the carboniferous shales of
England, as T. gracilis.

Position and locality: Chester group, Chester, Kaskaskia, and
other localities in Illinois, and Sloan's Valley and Litchfield in
Kentucky.

THAMNISCUS RAMULOSUS Ulrich.

PI. LXII, fig. 4-4b.

Zoarium a small frond, composed of delicate, frequently bifur-
cating branches, the bifurcations occurring at intervals of 1 or
2 mm. Branches rounded, from 0.3 to 0.5 mm. wide, two-
thirds as thick, connected to each other by slender dissepiments,
which never outnumber the bifurcations. Zooecia increasing
from three to five ranges between the bifurcations. Apertures
small, pustuliform, about 0.08 mm. in diameter, several times
their diameter apart, not very regularly arranged in oblique
transverse rows, with twelve in 3 mm. A small tubercle may
now and then be detected. Reverse with five or more longitu-
dinal striae, which are less distinct near the base of the frond.

var. SEVILLENSIS Ulrich.

PI. LV, fie. 6, and PL LXH, figs. 5-5a.

In this variety the zoarium spreads more rapidly than in the
typical form. The zooecia and their apertures are somewhat
larger, there being only nine or ten of them in 3 mm., while
there are also never more than four, and usually only three

BRYOZOA. 611

ranges throughout. The best specimen seen is slightly abraded.
yet shows faint evidences of granulose striations on the inter-
spaces.

This species, though having the branches united by dissepi-
ments whenever they approach each other closely enough, is
nevertheless a true species of Thamniscus. The fact that dissepi-
ments are also occasionally present in T. dubius, the type of
the genus, invalidates all objection to them in other species
having the really essential characters of the genus. Compared
with T. diraricans, the present species will be found much
smaller, the branches more frequently bifurcated, and the zocecia
apertures differently arranged. A more nearly related species
occurs in the Keokuk group at King's Mountain, Ky. It differs
mainly in having stronger branches.

Position and locality: The typical form is from the Chester
group at Sloan's Yalley, Ky., and has also been noticed on
slabs from Chester, 111. The variety is from the Lower Coal
Measures at Seville, 111.

THAMMSCUS OCTONARIUS Ulrich.

PL LXH, Fig. 7-7b.

Zoarium a small flabellate frond, somewhat higher than -wide,
produced by frequent bilateral dichotomization of a zigzag
primary branch. The bifurcations take place at such short in-
tervals that the spaces which separated the branches are usually
of less width than the branches. The angles between the bifur-
cating branches are rounded, while the separating ranges of
zooecia form acute angles, the intervals being occupied by sub-
triangular or wedge-shaped, concave, solid spaces. Obverse face
of branches moderately convex, 1.1 to 1.3 mm. wide. Zocecia
ranges increasing rapidly in number from three or four to seven
or eight between the bifurcations. Apertures circular, about
0.07 mm. in diameter, arranged in longitudinal series between
obscure raised lines, fifteen or sixteen in 5 mm., and in more or
less regular diagonal series. Peristome gradually rising about
the aperture, incomplete at its lower margin, spreading again
and gradually becoming obsolete below the aperture so as to

612 PALEONTOLOGY OF ILLINOIS.

enclose a faintly margined circular suboval depression. At the
bottom of this depression (which with the aperture resembles
the figure 8), I have in several instances detected a small pore.
Reverse convex, appearing smooth under the ordinary hand
lens.

This interesting species brings to mind several chilostomatous
Bryozoa, but, for the present at least, is fittingly referred to
Thamniscus. The superficial character of the zocecia, in fact,
the whole obverse face of the zoarium is quite different from
that of the ordinary species of the genus, making detailed com-
parisons unnecessary.

Position and locality: Upper Coal Measures; Greenwood Co.,
Kansas.

PHYLLOPORA King, 1849.

(Mon. Permian Fos. England, p. 40.)
(For generic diagnosis see page 397.)

The characters of this genus, as determined by an examina-
tion of P. ehrenbergi King, the type of the genus, place it in
the immediate neighborhood of Polypora. In its zooecial charac-
ters the type species agrees thoroughly with Polypora, the
most important difference between the two genera being that,
while in the latter, the branches are approximately straight
and united to each other by rythmically developed non-porifer-
ous bars, called dissepiments, they unite by inosculation to
form a regular round or oval-meshed network in Phyllopora.
The earliest true Phyllopora known to me is from the Upper
Helderberg group, and is next described under the name of P.
aspera. The Silurian Retepora species which I and others have
placed in this genus, are now known to possess very different
zocecia, and must be referred elsewhere, but mainly to the new
genus Phylloporina.

In American rocks true species of Phyllopora are very rare,
and up to this time I have met with only two undoubted
species, both of which are here described. A somewhat doubtful
third form is partially illustrated on plate LV. It agrees with
P. superba in having sub-rhomboidal fenestrules on the reverse,

BRYOZOA. 613

but on the obverse its branches are more distinct and occa-
sionally separated by a narrow non-celluliferous strip. Several
species of this type occur in the Hamilton group of New York
and Canada. It is not easy to decide whether they had better
go with Phyllopora or Polypora.

PHYLLOPOKA ASPERA Ulrich.

PI. XLTV. figs. o-ob.

Zoarium infundibuliform, celluliferous on the outer side, con-
sisting of anastomosing branches, forming a regular round
meshed net-work. Branches rather strongly convex, from 0.4
to 0.6 mm. wide. Fenestrules broad oval or circular, 0.2 or 0.3
mm. in diameter, smallest near the base, arranged in sub-regu-
lar longitudinal and diagonally intersecting series, with five
lengthwise and six diagonally in 5 mm. Zooecia in two or three,
usually alternating ranges. Apertures circular, about 0.13 mm.
in diameter, so far as observed, without a peristome, their di-
ameter or less apart, rather irregularly arranged, thirteen or
fourteen in 3 mm. Distributed over the surface among the
apertures are a variable number of strong blunt spines, giving
this face of the zoarium the rough aspect that suggested the
name. On the reverse the fenestrules are nearly or quite as
wide as the branches. Surface of the latter smooth or minutely
granulose.

The small size of the zoarium and fenestrules, and the ar-
rangement of the zooecia in only two or three rows on a branch,
distinguish this species from all others of the genus, save one,
known to me. The arrangement of the zooecia is very much
as in P. ehrenbergi.

Position and locality: Upper Helderberg group. Rare at the
Falls of the Ohio.

PHYLLOPORA SUPERB A Ulrich.

PI. XLIV, figs. 6-6c, and PI. LV, figs. 9, 9a.

Zoarium a reticulated flabellate expansion, known to attain a
height and width of between 4 and 5 cms.

614 PALAEONTOLOGY OF ILLINOIS.

Obverse face: Here the branches are strongly rounded, from 0.6
to 1 mm. wide, and appear to alternately approach and recede
from each other, so as to form elongate lozenge-shaped fenestrules.
Generally a narrow depression marks the line of junction between
the branches, causing the fenestrules to appear confluent. The fene-
strules are arranged in regular, diagonally intersecting and lon-
gitudinal series, with respectively 5.5 to 6 and 3.5 to 4 in the
length of 1 cm., each way. Zooecia usually in four ranges, with
three or five occasionally prevailing for a short distance. Aper-
tures sub-circular, small, with well developed but somewhat
oblique peristomes, arranged in more or less1 regular transverse
rows, of which about seventeen occur in 5 mm. Transversely
the apertures are about their diameter apart, but longitudinally
the interspace is about twice as great.

Reverse face: Here the branches are smooth, narrowly
rounded or angular, and with nearly flat sloping sides; the fene-
strules commonly rhomboidal, but sometimes regularly hexa-
gonal, and arranged in more or less curved intersecting series.
When of rhomboidal form there are exactly six in 1 cm., meas-
uring diagonally, and four in the same space vertically.

This beautiful species is distinguished from all the Hamilton
Bryozoa known to me by its large fenestrules and the total
absence of non-poriferous dissepiments. Two or three smaller,
yet very similar species, occur in the Upper Helderberg and
Hamilton groups, but all of them have their zigzag branches
united by appreciable, though very short and wide, dissepiments.

Position and locality: Hamilton group, Erie Co., N. Y.

PINNATOPORA Vine, 1883.*

(Fourth British Asso. Eept. on Foss Poly. p. 31.)
(For generic diagnosis see page 397.)

This name justly supplants Glauconome in its common use
for Palaeozoic Bryozoa, the original species of that genus, being
of a very different type, and most probably congeneric with
those for which Defrance previously proposed the now well es-

* The same name and for the same group of species was proposed by Mr. Shrub-
sole in 1884 (Proc. Chester Soc. Nat. Hist.) and conjointly by him and Mr. Vine in the
May number of the Quart. Jour. Geol'Soc., 1884.

BRYOZOA. 615

tablished name Yincularia. Both Vine and Shrubsole suggest
that the name Glauconome be retained for the G. disticha Lons-
dale. of the Wenloek shales. Perhaps d'Orbigny's name Penne-
retepora has a better claim. Should it prove upon investigation
that the Eifel species G. disticha Goldf. is again generically distinct
from both the Wenloek species and Pinnatopora, then all the
names might stand. In any event I believe we cannot do better
than to accept Pinnatopora as defined by Vine.

All the American species described under Glauconome have
the characters of Pinnatopora. There are four from the De-
vonian by Hall, and one each by Meek and White from the
Coal Measures. Fifteen or sixteen species referable to the genus
have been described from the Carboniferous deposits of Europe,
and one lately, from the Coal Measures of Ohio, by Foerste.
The following new forms bring the total number to 29 or 30
species*.

On plate LVI will be found figures of five species of the genus
illustrating variations in internal structure. In P. elegans, P.
conferta and P. trilineata. the zooecia form two distinct ranges
in both the midrib and branches, in P. retroflexa, those of the
midrib are somewhat lozenge-shaped, so that the cells of each
range are in contact only at their pointed extremities, while, in
P. laxa. they form one range in both midrib and branches. The
other species present each some slight intermediate modification
of zocecial form and arrangement. Hemisepta are, as a rule,
but little developed in Pinnatopora. but in P. trilineata, they
are exceptionally strong.

PINNATOPORA YOUNGI Ulrich.

PL LXVL fig. 3.

Zoarium pinnated, comparatively strong. Midrib strong,
averaging 0.6 wide, with the reverse side broadly convex and
finely striated. Obverse side somewhat flattened, with a strong,

* In December, 1888, (Bullet. Laboratories Denlson Univ., VoL 4.) the author pub-
lished d scription and figures of five additional species. These are from the Cuyahoga
shales of the Waverly series of Ohio.

616 PALAEONTOLOGY OF ILLINOIS.

rounded, mesial keel, bearing large, but not prominent, nodes
at intervals of about 0.8 mm. Entire obverse face between the
zocecia apertures very finely striated. Lateral branches short,
at their origin about three-fourths as wide as the midrib, ta-
pering rapidly toward their rounded distal extremities; opposite
or alternating, with eleven on each side in 1 cm., given off at
an angle of from 60° to 80°. Zooecia in two alternating ranges.
Apertures sub-circular, with a very thin and slightly elevated
peristome, about 0.1 mm. in diameter, and 0.35 mm. apart;
eleven in 5 mm. They are arranged so that one is opposite a
lateral branch and one between.

This species, though closely allied to several English and
Scottish species, is nevertheless quite distinct. Of American
forms P. vinei seems to be closer than any other, but differs in
being smaller and in having three zocecia where this has two.

The specific name is given in honor of Mr. John Young, of
Scotland, who, chiefly in conjunction with Dr. Young, has done
so much to bring out the minute details of structure of their
Carboniferous Bryozoa.

Position and locality: Keokuk group, King's Mountain, Ky.,
and Keokuk, Iowa; also in the Cuyahoga shales of Ohio.

PlNNATOPORA VINEI UMch.
PI. LXVI, fig. 5-5b.

Zoarium pinnate; midrib slender, usually straight, 0.4 to
0.45 mm. wide, with the reverse side evenly rounded and finely
striated. Obverse face low ridge-shaped, the mesial carina
rounded, not prominent, with rather strong nodes at irregular
intervals. Lateral branches from one to two mm. in length,
like the midrib but only two-thirds as wide, oppositely or sub-
alternately given off from the sides of the midrib; nine or ten
in 1 cm. Zooecial apertures in two alternating ranges, fifteen in
5 mm., subcircular, with faintly elevated thin peristome, about
0.1 mm. in diameter. All the interspaces between the apertures
very finely striated longitudinally.

The thinner midrib, longer lateral branches, and shorter zo-
cecia, distinguish this species from P. youngi with which it is
associated.

BRYOZOA. 617

Named as a slight token of my appreciation of the labors of
Mr. G. R. Tine on the Bryozoa of Great Britain.

Position and locality: Keokuk group, King's Mountain, Ky.,
Keokuk. Iowa, and in the Cuyahoga shales at several localities
in Ohio.

PETNATOPORA FLEXUOSA Ulrich.

PL LXVI, fig. 4-4c.

Zoarium pinnate, midrib 0.5 to 0.6 mm. wide, branchlets 0.3
to 0.4 mm. wide, and, when entire, about 2.5 mm. long. En-
tire obverse face, between the zooecia apertures, marked with
strong flexuous striae, those along the center of the branches a
little the strongest. An occasional tubercle present. On the
reverse both midrib and branchlets are rounded and finely
striated longitudinally. Near the junction of the latter with
the midrib, a small circular pore is often found. Lateral
branches sub-alternating, comparatively remote, averaging five
on each side in 1 cm., directed more or less distally. Zooecia
apertures in two alternating ranges, between ten and eleven in
5 mm., circular about 0.12 mm. in diameter, with well devel-
oped peristome.

This species is easily recognized by the rather remote lateral
branches, the non-development of a carina. and, particularly,
by the strong flexuous striations on the obverse side. The
peristomes too are stronger and more elevated than usual.

Position and locality: Keokuk group, King's Mountain, Ky.

PlNNATOPORA STRIATA UMch.
PL LXVI, fig. 4d.

Zoarium pinnate; midrib 0.5 to 0.7 mm. wide; branchlets
from 1 to 2 mm. long, 0.3 to 0.4 mm. wide, directed somewhat
distally. and fully as much toward the obverse side. Reverse
of midrib with rather coarse, unequal, longitudinal striae. Lat-
eral branches opposite or alternating on the two sides of the
midrib, with an average of nearly seven on each side in 1 cm.
—77

618 PALAEONTOLOGY OF ILLINOIS.

Primary portion of zooecia as well as their apertures in two
alternating ranges, eleven or twelve in 5 mm., the ranges sep-
arated by a well developed and faintly nodulose keel. Aper-
tures circular, widely sparated longitudinally, about 0.1 mm. in
diameter. Hemisepta well developed.

The specimen from which the above description is drawn
shows only the reverse, and was at first supposed to belong to
P. flexuosa. The more strongly striated reverse, and more
numerous pinnae, led me to make another examination. Thin
sections were prepared and these proved conclusively that it
belonged to a very different species, having a marked carina
and the primitive portion of the zooecia in both the branchlets
and midrib in two ranges. P. flexuosa, as may be seen on PI.
LXVI, fig. 4a, has the zooecia of the branchlets practically in
one range. P. vinei has shorter zooecia and a greater number
of branches, while in P. youngl the latter are shorter and more
numerous.

Position and locality: Keokuk group; Bentonsport, Iowa.

PlNNATOPORA CONFERTA Ulrich.
PI. LVI, fie. 5. and PI. LXVI. fig. 6.

Zoarium pinnate; midrib about 0.7 mm. wide, finely striate
on the reverse, with the carina on the obverse face elevated,
rounded, and, when perfect, bearing prominent nodes 1 mm. or
less apart. Lateral branches also carinate, with somewhat
closer nodes, 1.5 mm. long, about two-thirds as wide as the
midrib, of the same width throughout, separated by interspaces
very little wider than themselves, almost opposite on the two
sides, ten in 1 cm., given off at an angle of about 60°. Aper-
tures rather large, circular or slightly oval, 0.15 mm. in dia-
meter, with very faint peristome, about their own diameter
apart, with fifteen in 5 mm.

The distinctive features of this species are the large zooecia
apertures and the strong and closely arranged lateral branch-
lets.

Position and locality: Keokuk group, Keokuk, Iowa and
Jersey Co., 111. (Otter Creek).

BRYOZOA. 619

PlNNATOPORA TEXUIRAMOSA Ulrich,
PL LXYI. &g. 7.

Of this species only the reverse aspect has been observed. The
best fragment seen preserves a portion of the primary branch
about 1 cm. long. This is about 0.6 or 0.7 mm. wide, and
on one side throws off three, on the other only one secondary
branch, varying in width from 0.5 to 0.6 mm. The primary
and secondary lateral branches or pinnae, diverge at angles of
from 70° to 80°. are slender, about one-third as wide as the
principal branches, from less than 1 to nearly 3 mm. long,
those proceeding from the primary branch the longest, with
twelve or thirteen given off on each side in the space of 1 cm.
Surface of both branches and pinnae marked with fine but dis-
tinct longitudinal striae.

The characters relied upon in distinguishing this species are

(1) the number and comparative slenderness of the pinnae, and

(2) the great length of those that proceed from the sides of
the primary branch.

Position and locality: Waverly group, near Richfield, Ohio.

PlXNATOPORA BELLULA Ulrich.
PL LXVI, &g. 8-8b.

Zoarium a very slender, small, pinnate frond. Midrib between
0.2 and 0.3 mm. wide, throwing off subalternately from the two
sides, at an angle of about 50°. the pinnae, which have a width
of about 0.18 mm., and a length varying between 0.5 and 1
mm. Five pinnae on each side in 5 runi. Reverse side rounded,
granulose, the granules arranged in parallel longitudinal series
on fine elevated lines. Obverse face subangular or rounded,
without carina. but marked with flexuous striae, strongest near
the center of the midribs, where also a row of small and widely
separated (0.8 mm.) nodes may be observed. Zocecia in one
range in both midrib and pinna?. Apertures in two alternating
ranges, with about twelve in each in 5 mm., circular, 0.1 mm. in
diameter, surrounded by well developed peristome. They are

620 PALEONTOLOGY OF ILLINOIS.

so arranged that one is always opposite a pinna, and one in
the space between.

This species is closely allied to the P. flexicarinata (Y. & Y.
sp.) from the Carboniferous shales of Scotland. A comparison
with authentic examples of that species shows that the Scotch
form has six pinnae to 5 in this; and fourteen cell apertures to
twelve in P. bellula. The carina, nodes, and granulose striae of
the reverse are also all stronger than in the Illinois form. The
P. whitei Foerste, from an equivalent horizon in Ohio, differs
chiefly in having seventeen cell apertures where P. bellula has
only twelve.

Position and locality: Base of Coal Measures; Seville, 111.

PlNNATOPORA TRILINEATA Meek.

PL LXVI, fig. 6.
Glauconome trilineata Meek, 1872. Pal. East Neb. p. 157. PI. 7. flg. 4aV 4b-4d.

Zoarium a pinnate frond, the primary midrib 0.45 to 0.6 mm.
wide, giving off long secondary lateral midribs, 0.35 to 0.45
mm. wide, at intervals of 3 mm. or more. Pinnae 1.5 to 2 mm.
long, 0.3 mm. wide, nearly opposite, twelve on each side in 1
cm. Reverse face strongly rounded, distinctly marked with
longitudinal striae, those on the pinnae finer than those on the
midribs. Obverse face of midribs subangular, with three, fine,
straight lines along the center, the median one slightly the
strongest. Pinnae similarly marked but on a smaller scale.
Zocecia and their apertures in two ranges in both midrib and
pinnae. Apertures circular, 0.09 mm. in diameter, about
twice as far apart longitudinally, with seventeen in 5 mm.; so
arranged that one occurs opposite the upper half of the base of
each pinna, and two in the space between. When in a good
state of preservation they are surrounded by a thin and sharply
elevated peristome. Of internal characters the strong develop-
ment of hemisepta is the most noteworthy.

The three mesial lines constitute the principal external peculi-
arity of this species.

According to Meek's measurements, between eight and nine
pinnae are given off on each side in 1 cm. I have examined per-
haps one-hundred fragments and all give twelve in that space.

BKYOZOA. 621

The specimen represented by Meek's fig. 4a (loc. cit.), from
which his measurements were evidently derived, has much longer
pinnte than any yet seen by me, and I doubt very much that
it is the same species. It is attached to the matrix so that the
reverse side only could be seen. Figures 4c and 4d, represent-
ing the obverse side, agree with my own observations in all
respects excepting that the pinnae are too thin. Possibly a young
example was selected. In any event, it does not seem probable
that the Upper Coal Measures of Nebraska- contain two triline-
ate species.

Position and locality: One of the most characteristic species
of the Upper Coal Measures. Examples are abundant at locali-
ties in Sangamon County, 111. The original specimens are from
Nebraska City, Nebraska.

PTILOPORA McCoy, 1844.

(Syn. Carboniferous Foss. Ireland, p. 200.)
(For generic diagnosis see page 398.)

I have been in doubt whether this genus presented closer re-
lationship to the FENESTELLID.E or ACANTHOCL ADHERE. After
much thought I have concluded that the pinnate form of growth
must outweigh the dissepiments, the former being the result of
peculiarities in zooecial development, while the latter seem to
indicate nothing beyond an economical manner of giving solidity
and strength to the zoarium. It is true, of course, that in such
a species as P. paupera we see resemblance to some Fenestellids,
but on the other hand, P. valida and P. cylindracea, while pos-
sessing all the essential characters of Ptilopora, so closely re-
semble Pinnatopora. that a greater than generic separation is
out of the question.

True species of the genus are first met with in the Hamilton
group, one is known from the Burlington limestone, three or
four from the Keokuk, and one, possibly two. from the Warsaw
and St. Louis beds.

622 PALAEONTOLOGY OF ILLINOIS.

PTILOPORA ACUTA Ulrich.

PI. LXV. Fig. 4-4a.

Zoarium a large pinnate frond, the largest fragment seen
having a width of 3 cm. from the central shaft to the lateral
margin.

Reverse. Mid rib strong, from 1.0 to 1.5 mm. in width, ap-
pearing like a cylindrical stem lying on the surface of the frond,
and marked with distinct longitudinal striae. Branches rather
slender, generally a little flexuous, springing from the shaft,
eight or nine in 1 cm., at angles varying in different examples
from 22° to 42°. As in the specimen figured the angle may be
quite different on the two sides of the shaft. Still, 30° seems
to be about the normal. The average width of the branches is
about 0.3 mm., but in extreme cases it may vary from 0.2 to
0.5 mm. Measuring at right angles to their direction, from
thirteen to fifteen branches occur in 1 cm. Dissepiments slightly
depressed, on a level with the branches, or somewhat elevated
above them, usually a little wider than the branches, but vary-
ing in width from 0.3 to 0.7 mm. Surface of branches and dis-
sepiments finely striated. Fenestrules long-oval, about 1.3 by 0.5
mm., with six in 1 cm.

Obverse face not well shown by any of the material before me,
but, so far as can be determined, shows, that the midrib has a
strong, rounded and striated keel, two ranges of zocecia, with
large apertures separated by a space about equal to their
diameter, and that there are fourteen apertures in 5 mm.

The larger frond, more rounded midrib, and more acute angle
at which the branches and midrib meet, distinguish this species
from the associated P. valida. The Warsaw and St. Louis P.
prouti has much shorter fenestrules, and closer and less acutely
arranged branches.

Position and locality: The types are from the Keokuk group
at Bentonsport and Keokuk, Iowa, but what seems to be the
same species is represented in the Illinois State Museum by a
specimen from the Burlington limestone, at Burlington, Iowa.

BRTOZOA. 623

•

PTILOPORA VALIDA Ulrich.

PL LXV. fijfs. 5-5-, PL LXVI, figs. 1-lb.

Zoarium a narrow, pinnated frond, the entire width not known
to exceed 1.5 cm., often closely resembling a robust Pinuato-
pora.

Eevei-se. Midrib comparatively strong, convex, 0.7 to 1.3
mm. wide, and like the branches finely striated longitudinally.
Branches comparatively short, rather rigid, 0.4 to 0.5 mm.
wide, given off from the midrib at an angle of about 55°,
averaging ten on each side in 1 cm. At long intervals one of
the branches grows stronger than the rest, and forms a new
midrib, with branches like the primary one. Dissepiments de-
pressed, thin, generally about 0.2 mm. wide, rarely more than
three between any pair of branches. Fenestrules oblong sub-
quadrate or oval, with average dimensions of 1.3 by 0.5 mm.;
three occupy a space nearly 5 mm. long.

Obverse. Midrib with a strong rounded carina, carrying small
nodes about 2 mm. apart. Branches subcarinate, also with
small but more closely arranged nodes. Zocecia in two ranges
on both midrib and branches. Apertures rather large, fourteen
on the midrib and sixteen on the branches in 5 mm., their
diameter or less apart. With age, the midrib thickens and the
apertures are covered by a finely striated deposit. Often, too,
the branches are broken away, when the fossil presents an ap-
pearance that at first sight is quite puzzling and liable to cause
mistakes.

The narrow fronds and thin dissepiments separate this species
from P. acuta.

Position and locality: Keokuk group. Bentonsport and
Keokuk, Iowa, and Jersey Co., 111.

PTELOPORA CYLINDRACEA Ulrich.

PI. LXVI, fig. 2-2b.

Zoarium when complete a narrow pinnate frond, with the
branches extending about 5 mm. on each side of the midrib.
Usually the branches are all broken away so that the zoarium
looks like a slender rod with two ranges of small cells, and two

624 PALEONTOLOGY OF ILLINOIS.

more widely separated large openings beneath them. The latter
represent the broken branches.

Reverse. Midrib prominent, subcylindrical, from 0.6 to 0.8
mm. wide, and like the branches finely striated. Branches sub-
cylindrical, rigid, 0.3 to 0.4 mm. wide, twelve to fourteen given
off from the midrib, at an angle of about 65° in 1 cm. Dissep-
iments easily overlooked, depressed, very thin, two or three in
number, about 1.1 mm. apart. Fenestrules narrower than the
branches.

Obverse. Midrib with a more or less defined, low, rounded,
central ridge, carrying a row of small hollow nodes, 0.4 mm.
apart, and, in the younger stages, with a fine line on each side.
In old examples the whole space between the ranges of aper-
tures is almost uniformly rounded, but without obliterating the
nodes. The surface of the branches is simple rounded, but a
similar row of small nodes runs along the center. Zocecia in
two ranges. Apertures submarginal, very small, circular or sub-
oval, with prominent but not abruptly elevated peristome,
thirteen or fourteen in 5 mm. on both midrib and branches. On
the former they are situated one at the base of each branch
and one midway between.

When found in shale, the substance of the zoarium has a
polished aspect that is not shared by any of the associated
Bryozoa.

This species, like P. valida, might easily be mistaken for
Pinnatopora, and, indeed, I believe that the short branches and
thin dissepiments of these two forms, point to a clear relation-
ship with species of that genus.

Position and locality: Keokuk group, King's Mountain, Ky.,
and Bentonsport, Iowa. The examples from the last locality
have the branches slightly wider apart than the Kentucky
specimens. The last being the most perfect and numerous, are
considered as the most typical.

PTILOPORA PAUPER A Ulrich.

PI. LXVI, Fig. 10.

Zoarium a small, rather irregularly pinnate frond, with the
hight and width about equal. Midrib and branches strong and

BRYOZOA. 625

much thickened near the base, rapidly tapering upward. In the
upper half of the frond the midrib is usually less than one-third
stronger than the branches, the latter being about 0.3 mm.
wide. Here the branches are lax, flexuous, and bifurcate rathej
frequently, a feature of very unusual occurrence among species
of the genus.

Reverse. Branches and midrib moderately convex and finely
striated. Midrib slightly flexuous, tapering upward, giving off
on each side about nine branches, at an angle of near 45°, in
1 cm. Branches connected by slender dissepiments forming
comparatively large irregular feuestrules, of which about four
follow each other in 5 mm.

Obverse. Midrib and branches subcarinate, the rounded keel,
over the basal half of the zoarium, with closely arranged small
nodes. Over the outer half the keel is somewhat sharper, the
nodes less distinct, and, perhaps, wanting. Zooecia apertures
sub-oval, iu two ranges, about their diameter apart, sixteen or
seventeen in 5 mm.; with moderate peristome.

The characters of the basal portion of the frond mentioned in
the above description have been derived from the central speci-
men of fig. 10. It is possible that this specimen may not be-
long to the same species as the other two represented in the
figure. It shows the obverse side, but most of the zooecia aper-
tures are closed by a striated deposit, so that I could not
satisfy myself in determining their number in a given space.
The few that can be seen appear larger than in the true types,
and I estimate that there are not more than thirteen or four-
teen in 5 mm.

The small size and lax growth of the zoarium distinguish the
species from all others known to me.

Position and locality: Keokuk group. King's Mountain, Ky.

PTILOPORA PROUTI Hall.

PI. LXV. fig. 3-3c.
Ptilopora prouti Hall, 1858. Pal. Iowa, p. 653, PI. 22, figs. 6a-6c,7.

Zoarium a pinnate frond, attaining a height of 6 or 7 cm.,
and a width of 5 or 6 cm. Midrib rather strong, commonly
about 1 mm. wide, giving off on each side about eleven or twelve
—78

626 PALAEONTOLOGY OF ILLINOIS.

branches, at the angle of about 50°, in 1 cm. Branches some-
what flexuous, averaging 0.4 mm. wide, but varying between
0.8 and 0.7 mm., the last just before bifurcating. Bifurcations
rare, occasionally met with near the midrib, but usually occur-
ring only in the outer half of the expansion. Zooecia in two
ranges on both midrib and branches, increasing to three before
bifurcation takes place.

Reverse. Midrib prominent, sub-cylindrical, finely striated.
Branches commonly a little flexuous, but sometimes quite rigid,
striated, connected by depressed dissepiments two-thirds as wide
as the branches. Fenestrules oval, about 0.5 by 0.3 mm.,
slightly longer in the outer portions of the frond, with nine or
ten in 1 cm.

Obverse. Midrib with two narrow channels in which the zooecia
apertures are situated, and, between them, a strongly convex
and striated carina, bearing large nodes at intervals of 1 mm.
Branches sub-carinate, also with nodes but with them closer
together. Zooecia apertures .circular, a little more than their
diameter apart, with fifteen in 5 mm. on the midrib, and seven-
teen in the same space on the branches. Those of the branches
have distinct peristomes, most elevated on the outer side.

The compact appearance of the zoarium, caused by the com-
parative strength of the branches and midrib, and the small
fenestrules, serves to distinguish this species at a glance from
P. acuta.

Position and locality; Warsaw7 beds, Warsaw, 111., and Mon-
roe Co., 111., and near New Providence, Ind. Also in the lower
beds of the St. Louis group at Barrett's Station, Mo.

SEPTOPORA Prout, 1859.

Trans. St. Louis Acad. Nat. Sci. Vol. l,p. 448.
(For generic diagnosis see page 397.)

This genus includes some very interesting but, at the same
time, exceedingly difficult forms. They required much study,
and had I not had an abundance of good material to work
upon, the following classification into species and varieties
would have been nearly impossible.

The various species here defined may be divided into two
groups; the first, comprising S. cestriensis, S. subquadrans, and

BRYOZOA. 627

S. decipiens, having the number of branches increase mainly by
bifurcation; the second, containg S. biserialis, S. biserialis var.
nervata, S. pinnata,S. robusta,S. robusta var. intermedia, and S.
delicatula, having the number increase entirely by interpolation.
The first group is, so far as known, only represented in the
Chester group, while the second, though occasionally met with
in those beds, is almost restricted to the Upper and Lower Coal
Measures. The discovery of this fact aided greatly in the sepa-
ration of the species.

The position of the genus is between Pinnatopora Vine and
Synocladia King. Both Meek and Swallow regarded S. biseri-
alis as a species of Synocladia, but that they were in error is
now generally admitted. S. virgulacea King, the type of that
genus, has from three to five ranges of zocecia, and, so far as
known, is without the small accessory pores which are so char-
acteristic of all the species of Septopora. The relations to
Pinnatopora, though very evident, have not heretofore been
pointed out. Take for instance S. decipiens, and we find upon
comparison with species of Pinnatopora, that the only im-
portant character not common to them are the accessory pores.
The importance of even this distinction is diminished by the
discovery of similar pores on the reverse of Pinnatopora tiexu-
osa. All the remaining species of Septopora form a fenestrated
expansion by the union of the pinnae of neighboring branches.
The appearance of the ordinary zoarium of the two genera is.
therefore, quite different, but, here again, P. sedgwicki Shrub-
sole, lessens the utility of the difference, being likewise possessed
of a fenestrated zoarium. Certain differences in the internal
structure of species of -these two genera may be noticed in
comparing the figures on PI. LVI. S. robusta, in having three
ranges of zooecia on the pinnee, or as they are usually called, the
poriferous dissepiments, approaches Acanthocladia and Syno-
cladia, two genera that hold the same relations to each other
as Pinnatopora and Septopora.

628 PALEONTOLOGY OF ILLINOIS.

SEPTOPOKA CESTKIENSIS Prout.

PI. LXIV, flg. 1-16.

Septopora cestriensis Prout. 1859. Trans. St. Louis, Acad. Sci. Vol. I. p. 448, PI. 18,

figs. 2-2& (pars).
(Not Septopora cestriensis Meek & Worthen, 1870. Geol. Surv. 111. vol. V, PI. 24, flg.

14a-14c.)

Zoarium a rather delicate but compactly woven flabellate ex-
pansion. Branches not very rigid, averaging from twelve to
fourteen in 1 cm., increasing in number by bifurcation and not
by interpolation, with an average width of 0.5 mm., but en-
larging from 0.3 or 0.4 mm. immediately after bifurcation to
0.7 or 0.8 mm. before the next division.

Reverse. Branches narrowly rounded, slightly zigzag or
straight, striated wrhen young and smooth on mature or old
examples; accessory pores rather large, about 0.09 mm. in di-
ameter, not very numerous, situated generally opposite the
connecting branchlets or dissepiments. The latter are generally
a little thinner than the branches and on the same level with
them. Fenestrules varying in shape from circular or oval to
sub-quadrate, commonly between ten and eleven in 1 cm.; but
some otherwise typical specimens have twelve or thirteen in
that space.

Obverse. Branches sub-angular, with a faint mesial keel,
which is most prominent on worn examples; generally the keel
expands at intervals of 1 mm. or less into rather prominent
elongated nodes. The dissepiments extend directly across from
branch to branch, and expand at their junction with them,
causing rounded fenestrules to prevail. Near the outer margin
of the frond the fenestrules are likely to be sub-quadrate. Zooe-
cia in two ranges, but -a third is occasionally interpolated just
before a bifurcation. Apertures circular, 0.14 mm. in diam-
eter, about two-thirds of their diameter apart, twenty-two or
twenty-three in 5 mm. Peristome thin and but little elevated.
On the dissepiments the rule is to find four apertures, two on
each side. Often, however, a fifth will occupy the central point,
while at other times the number is reduced to three or even
two. A small number of the accessory pores occur among the
zooecia apertures, but on this side they are usually restricted
to the dissepiments.

BRYOZOA. 629

The distinguishing features of this species are, the compact
appearance of the net-work, the small rounded fenestrules, large
number of branches in a given space, the short dissepiments
and few zooecia on them, and the comparatively large size of
the accessory pores. These differences apply particularly to its
nearest relative and associate S. subquadrans.

In the above I have restricted S. cestriensis to the small round
meshed form, that was used by Prout when he illustrated his
species, and which is particularly characteristic of the beds at
Chester, 111. The larger, or better, the less compact form which
he, and Meek and Worthen after him, considered the same, can
and ought to be separated.

Position and locality: Lower and middle beds of the Chester
group. Not uncommon at Chester, 111. Rather rare at Sloan's
Valley and several localities in western Kentucky.

SEPTOPORA SUBQUADRANS Ulrich.

PI. LVI, flg. 7, 8, and PI. LXIV, figs. 2, 2b.
Septopora cestriensis M. & W. 1870. Qeol. Surv. 111. vol. 5, pi. 24, flgs. 14a-14c.

Zoarium a large, flabelliform, undulating or flat net-work,
consisting of approximately equal radiating branches, united by
somewhat thinner, and more or less arched dissepiments, leav-
ing transversely elongated fenestrules varying in form from sub-
quadrate to irregularly crescentic. Branches increasing by bi-
furcation, averaging 0.5 mm. in width, and about ten in 1 cm.,
but extremes like seven and twelve in 1 cm., have been noticed.
Fenestrules averaging 0.7 mm. wide by 0.5 mm. long, and vary-
ing between ten and one-half and twelve in 1 cm. Keel rounded,
moderately prominent, with strong tubercles at intervals of
0.7 mm. Zooecia in two ranges, with from four to twelve, nor-
mally, six to eight on the dissepiments, and twenty-one in 5 mm.
in each range on the branches. Apertures circular, with faint
peristome, somewhat less than their diameter apart. Accessory
pores small, distributed irregularly among the zooecia and on
the reverse side of the branches. Fig. 2b shows their usual
position and number. When in a good state of preservation
they are elevated, sometimes to such an extent that the re-
verse side of the frond appears quite rough. Reverse finely

630 PALAEONTOLOGY OF ILLINOIS.

striated on young examples, but near the base the striae are
always obsolete. On this side the branches appear rather rigid,
and project more or less above the plane of the dissepiments.

The above briefly describes the principal characters of this
variable species. For comparisons between it and S. cestriensis
see description of that form. Compared with S. biseriaJis^the
main difference will be found in the mode of increase in the
number of branches, the method in this species being by bifur-
cation, while in the Coal Measure form the new branches are in-
terpolated, 7. e,, developed from the dissepiments or from the
side of an older branch. The difference in this respect is fairly
shown in two figures published by Meek and Worthen in vol. V,
PI. 24, of this series of reports.

Position and locality: Upper limestones of the Chester group.
Abundant at Sloan's Valley, and other localities in Kentucky;
less common at several localities in Illinois.

SEPTOPORA DECIPIENS Ulrich.

PI. LXVJI, fig. 9.

Zoarium a narrow pinnate stipe, dividing dichotomously at
distant intervals, with often a fenestration for a short distance
above the bifurcation. In one instance, the lateral branches
have grown to be about 2 mm. long, and are connected by a
celluliferous dissepiment, situated 1.2 mm. from the midrib or
branch. Usually the pinnse are short, sub-carinate, taper rapidly,
with twelve or thirteen on each side in 1 cm. Midrib increasing
gradually in width from 0.5 to 0.9 or 1.0 mm. between bifur-
cations; on the obverse with a well defined rounded carina, car-
rying faint nodes 1 mm. apart. Zooecia in two ranges except
often just beneath a bifurcation where three rows may prevail
for a short distance. Apertures rather large, suboval, 0.15 mm.
long, as much or less apart, seventeen in 5 mm. Peristome
very faint. Accessory pores small, about 0.5 mm. in diameter,
distributed at irregular intervals among the zooecia apertures.
Reverse of midrib rather broadly rounded, very finely striated,
with a small number of accessory pores. The latter are easily
overlooked. The enlarged view of the obverse face given on

BRYOZOA. (331

PI. 66, is faulty in having the cell apertures too small, and in
not showing- any accessory pores. The latter were first detected
after the plates had been printed.

The isolation of the branches and consequent resemblance to
Pmnntopom. distinguish this species from S. subquadrans. The
zooecia are also slightly larger. Fragments of similar appear-
ance, but apparently belonging to a distinct species, have been
noticed. One of them is represented by fig. 9a, on PI. 66. This
agrees very closely in its minute features with S. subquadrans,
and may represent a variety of that species.

Position and locality: Chester group, Sloan's Valley, Ky.

SEPTOPORA BISERIALIS Swallow.

PI. LVI, fig. 11.

Synocladia rirgulacea? Swallow. 1858. Trans. St. Louis Acad. Sci. vol. 1, p. 179.

Syttocladia biserialis Swallow, 1858. Trans. St. Louis Acad. Sci. vol. 1, p. 179.

Synocladia biseriaUs Meek, 1872. Pal. E. Neb. p. 156, pi. 7, flg. 5a-5e.

>ynocladia biserialis Meek, 1874. Am. Jour. Sci. and Arts. p. 486.

Synocladia biserialis Meek, 1875. Pal. Ohio, vol. 2, p. 326, PI. 20, flg. 5-5b.

Synocladia biserialis White, 1877. Wheeler U. S. Geol. Surv. vol. 4, p. 107, PI. 7, flg. 3a-3c.

Zoarium large, irregular, infundibuliform, strongly folded and
often overlapping in the upper portions, consisting of approxi-
mately equal, parallel radiating branches, their number increas-
ing by lateral divisions, or intercalation of new branches, the
whole being united into a fenestrated frond by the union of the
lateral branchlets or pinna?, which form more or less arched
dissepiments. Fenestrules usually transversely oblong, often
irregularly quadrangular or somewhat crescentic, wider than
the branches, about thirteen in 1 cm. Branches averaging 0.5
mm. wide, but varying from 0.3 or 0.4 to 0.7 or 0.8 mm., with
nearly uniformly ten in 1 cm.; reverse evenly rounded, with fine
minutely granulose striae, and a variable though never large
number of accessory pores, chiefly occurring on the sides of the
branches; their mouths are circular, about 0.07 mm. in diame-
ter, and, when perfect, with a slightly elevated rim. The dis-
sepiments are about two-thirds as wide as the branches, and.
on the reverse side, more or less depressed below them, and
striated. On the obverse face the branches and dissepiments

632 PALAEONTOLOGY OF ILLINOIS.

present two ranges of rather large, sub-circular zooecia aper-
tures, separated by a thin mesial ridge, which is stronger on
the branches than on the dissepiments, and carries a series of
elongate, more or less prominent nodes, 0.8 mm. or less apart.
Zooecia apertures 0.13 mm. in diameter, about two-thirds their
diameter apart, with twenly or twenty-one in 5 mm.; and from
three to eight on each dissepiment; when well preserved with a
thin but distinct peristome. Irregularly distributed between the
apertures, especially on the dissepiments, there are accessory
pores of the same nature and size as those on the reverse side
of the zoarium.

The measurements of this species agree very closely with
those of S. subquadrans, but there are, nevertheless, certain
differences that show them to be distinct. In the Chester form
the branches increase by true bifurcation, while in S. biserialis
the mode is by lateral division and interpolation. Another dif-
ference will be noticed upon comparing figs. 7 and 8 with fig.
11 on PL LVI. These represent the appearance of the two
species in thin sections, and show a minute dotted character of
the dense reverse layer and the zooecia interspaces in the Car-
boniferous species that is entirely absent in S. subquadrans.
The ultimate form of the zoarium also shows some differences,
the latter being characterized by its slightly undulated flabel-
late form, while S. biserialis forms a strongly folded infundibuli-
form zoarium. On the whole, therefore, I believe the specific
separation is justified.

Position and locality: Upper and Lower Coal Measures, at
localities in Illinois, Iowa, Kansas, Nebraska, Missouri, and
Kentucky.

SEPTOPORA BISERIALIS VAR. NERVATA Ulrich.

PI. LXIV, flg. 6.

This designation I propose provisionally for a form repre-
sented in the collections before me by seven examples. They
differ from the typical form of the species in having primary
and secondary branches, the former being much stronger than
the latter, and arranged in a radial manner around the base.
The secondary branches are thinner, nearly parallel with each

BRYOZOA. 633

other, and given off from one or both sides of the primary set
at a very acute angle. At intervals one of the secondary
branches becomes thickened and is likewise pinnated. The fenes-
trules are sub-quadrate or ovate, generally a little \vider than
the branches, with eight or nine in 1 cm. in six of the speci-
mens, and between ten and eleven in the seventh. In other re-
spects the variety agrees with the typical form.

Three of the specimens * are from the Chester group of Ken-
tucky, three from the Upper Coal Measures of Illinois, and one
from the same horizon near Red Oak, Iowa.

SEPTOPORA PIXXATA Dlrich.

PL LXTV, fig. 7. PL LXV.flgs, 1-la.

This form agrees in many respects with S. biserialis, but the
pinnate arrangement gives it such a different aspect that it
seems unreasonable to regard them as specifically identical.
Their relations are about the same as those of S. decipiens to
S. subquadrans. In distinguishing it from the var. nervata. we
find that the branchlets are given off at a much less acute
angle, and that altogether the branches are thinner and the
fenestrules comparatively larger. Eight branchlets, averaging
0.3 mm. wide, are given off from each side of the midribs, in
1 cm. The midribs vary from 0.5 to 0.7 mm. wide.

Position and locality: Upper Coal Measures, Jasper County,
Illinois.

SEPTOPORA ROBUST A Ulrich.

PL LVI. fig. 9-9c, and PL LXTV, figs. 3-3a.

The zoarium of this species is flabellate, and, though with
many points of resemblance to S. biserialis, will be immediately
distinguished by its more robust appearance, the branches hav-
ing an average width of between 0.7 and 0.8 mm., the extremes
being 0.6 and 1.1 mm; five to eight branches occur in 1 cm.
The dissepiments are either direct or arched, strong, from 0.4
to 0.7 mm. wide, and somewhat depressed on the reverse side;
the fenestrules vary from circular to transversely oblong sub-
quadrate, usually wider than the branches, with seven or eight
—79

634 PALAEONTOLOGY OF ILLINOIS.

and rarely nine in 1 cm. longitudinally. The zooecia form two
ranges on the branches, with twenty-two or twenty -three in 5
mm., and three irregular rows on the dissepiments. The aper-
tures are comparatively large, being 0.14 mm. in diameter, and
separated by little more than half their diameter. One of the
principal features of the species is the large number of the
accessory pores on the reverse side. A few of these pores also
occur among the zooecia apertures.

Position and locality: Upper Coal Measures, Fayette County,
Illinois.

SEPTOPOBA ROBUSTA var. INTERMEDIA Ulrich.

PI. LVI, fig. 10, and PI. LXIV, figs. 4-4a.

Under this provisional name I desire to make known a form
from the Chester limestone of Kentucky, that differs from the
typical form in having more delicate branches, and longer and
more arched dissepiments. The former vary in width between
0.4 and 0.7 mm., and the latter usually carry only two rows
of zooecia. There are three specimens, two from near Litchfield
and one from Sloan's Valley. One preserves the base with a
large number of rootlets.

SEPTOPORA DELICATULA Ulrich.

PI. LXIV, fler. 5-5a.

Of this species only the reverse is known, but this is so char-
acteristic that there is no danger of mistaking the species. The
zoarium is small and exceedingly delicate. The branches are
rather narrowly rounded, distinctly striated, and vary in width
between 0.2 and and 0.4 mm. The intervals between them
average 1.2 mm. Dissepiments or connecting pinnae slender,
about two-thirds as wide as the branches, and 1.2 to 1.5 mm.
distant from each other. A few accessory pores are developed,
usually at the base of the dissepiments.

Position and locality: Lower Coal Measures, Seville, Illinois.
Associated with Fenestella wortheni, F. sevillensis, Rhombopora
multipora, (Foerste) and other species.

BRYOZOA. 635

ACANTHOCLADIA King, 1850.

(Monograph Brit. Perm. Foss. p. 48.)
(For generic diagnosis see p. 398.)

On plate LYI figures 1 to Ic, illustrate the internal charac-
ters of A. anceps Schlotheim, the type of the genus. According
to my observations, the zooecia are arranged about as follows:
In A. anceps there are generally four alternating rows of zooecia
on the main branch, but the number varies from three to six.
Of these the two central ranges are the principal ones, since
they run without interruption throughout the length of the
stem, while the one or two rows on each side of them are often
discontinuous. This fact argues a relationship to Septopora
that is better shown in A. fruticosa, in which, though with
ample room for them, the lateral rows are developed only along
the line of junction with the lateral branches. In both species
the lateral branches or pinnae have three ranges of cells. Another
feature common to both Septopora and A. fruticosa are the
small accessory pores. I have, however, not detected them on
the reverse side of the Permian species.

ACAXTHOCLADIA FRUTICOSA UMch.
PI. LXV. fig. 2-2c.

Zoarium strong, fruticose, pinnated, with the primary branch
giving off similar pinnated branches at frequent but irregular
intervals. Pinnae short, varying in length, between 1 and 3
mm.; 0.6 to 0.9 mm. wide, tapering slightly, with the free ends
obtuse. Primary branches' from 1 to 1.5 mm. wide, giving
off on each side, seven pinnae or lateral . branches in 1 cm.

Obverse face showing three, often irregular alternating rows
of zooecia apertures on the pinnae, and two central rows on the
midribs. The latter are situated in two deep furrows, with six-
teen in 5 mm., and are generally flanked on one or both sides
by an intermediate row which more properly belongs to the
series that pass on into the pinnae and lateral branches. Aper-
tures circular, with no appreciable peristome, about 0.1 mm.

636 PALEONTOLOGY OF ILLINOIS.

wide, and about one and a half times their diameter apart. On
the ridges chiefly, will be found small accessory pores, about
equal in number to the zooecia.

Reverse face very finely striated, rather strongly rounded,
with numerous accessory pores arranged in a line near the
margins of the branches and pinnae.

The shrubby appearance of the zoarium, the three ranges of
zooecia on the pinnae, and the accessory pores, induced me to
place this species with A canthocladia, the greater persistence of the
lateral rows of pores on the main stem of A. anceps being re-
garded as of only specific importance. I am not acquainted
with any bryozoan in American Carboniferous rocks that could
for a moment be confounded with A. fruticosa. What Swallow's
A. americana may be, has not been determined, but his meagre
description is nevertheless sufficient to show that it can not be
the same as the present species.

Position and locality: Upper Coal Measures, near Springfield,
Illinois.

DIPLOPORA Young and Young, 1875.

(Proc. Nat. Hist. Soc. Glasgow.)
(For generic diagnosis see page 398.)

The above name was proposed by the authors cited as a sub-
generic division of Glauconome (Pinnatopora). They include
under it only one species which they call G. (Diplopora) margi-
nalia, and describe as having a pore beneath each zooecia aper-
ture. As I have already shown, this supposed auboral pore is
the result of attrition whereby the convex front of the cell was
partially worn away, leaving the superior hemiseptum to sep-
arate the "pore" from the aperture. As, however, the species
is one of several deviating from Pinnatopora in wanting the
pinnae, I have concluded to adopt their name in a generic sense.

Beside D. marginalia, which is from the Scotch Carboniferous
shales, I have met with three other species. One of these has
lately been described from England, by Mr. Vine, as Pinnato-
pora? simplex; the remainder are from Illinois, one from the
Lower Coal Measures, the other from the Chester. The latter
is somewhat doubtful as it differs from the others in having
its branches divided dichotomously.

BRYOZOA. 637

DlPLOPORA BIFTJRCATA Ulrich.
PI. LXIL fie. ia-12a.

Zoarium very small, consisting of slender sub-cylindrical
dichotomizing branches, about 0.3 mm. in diameter, bifurcating
at intervals of from 1 to 3 mm. Obverse side with two ranges
of small, zooecia apertures, situated along the margin to which
their rather prominent peristonies give a slightly wavy outline.
Apertures circular, about 0.08 mm. in diameter, twice their dia-
meter apart, with twelve in 3 mm. Between the ranges of aper-
tures the surface is rather narrowly rounded but not carinate,
and occasionally exhibits a small tubercle. Reverse of branches
finely striated.

It is not improbable that this species has closer affininities with
such species of Thamniscus as T. furcillatus, which it resembles
in the dichotomization of its branches; but, in the present state
of our knowledge, the two ranges of zooecia seem to demand
recognition, and I have accordingly placed the species here.

Position and locality: Chester group, Chester, Illinois.

DlPLOPORA BISERIALIS Ulrich.

PI. Lxn, fig. n-iic.

Zoarium consisting of very slender, sub-cylindrical, straight
or slightly curved stems, nearly 0.3 mm. wide and somewhat
less in thickness, which throw off, at variable but long intervals
precisely similar lateral branches. Margins wavy, due to the
projection of the zooecia apertures. Reverse of branches finely
striated, evenly rounded. Obverse, with two ranges of alterna-
ting zooecia. Apertures subcircular, marginal, opening obliquely
outward, with elevated peristome, about 0.1 mm. in diameter,
once and a half to twice their diameter apart, with twenty in
5 mm. Surface between the ranges of apertures subangular,
and marked with faint, intermittent, longitudinal striip.

The Scotch D. warginalis Y. & Y., to which this species is
closely allied, has a thin tuberculated central keel, and usually
another on each side of it. The reverse is also granulo-striate.

Position and locality: Lower Coal Measures. Seville, 111.

638 PALEONTOLOGY OF ILLINOIS.

SPHRAGIOPORA Ulrich.

(For generic diagnosis, see page 398.)

Although externally somewhat resembling the isolated colonies
of Botryllopora Nich., the species upon which this genus is
founded proves upon investigation very different. That genus
exhibits little to distinguish it from the FISTULIPORID^:, while S.
parasitica in no feature reminds us of that family. Taking only
the zooecial characters into consideration the genus agrees very
closely with both the FENESTELLHLE and ACANTHOCLADIIDJD. The
zoarium is however so very different that a reference to either
one of those families seems out of the question.

SPHRAGIOPORA PARASITICA Ulrich.

PL LXV, fig. 6, 6a.

Zoarium a small disc-shaped body attached parasitically to
foreign objects; very frequently the strong supports of Lyro-
pora. Upper surface flat or a little concave; base smooth, form-
ing a margin around the raised celluliferous portion. Diameter
of zoarium, when mature, from 1 to 2 mm., height about 0.5
mm. The smallest specimen seen is 0.32 mm. in diameter. On
a mature example the zooecia apertures are arranged in an ir-
regularly radial manner about the center, upon the summits of
six to nine more or less elevated ridges. At first they form
only single rows, but at the outer margin the arrangement is
biserial. A cyclic arrangement is also more or less evident.
Apertures subcircular, about 0.09 mm. in diameter, generally
with a faint peristome, occasionally preserving rayed operculum-
like covers. A variable number of irregularly distributed acces-
sory pores and tubercles also present.

Position and locality: Chester group, Chester, 111. What may
prove another species occurs attached to shells in the Upper
Coal Measures of Illinois. Its zoarium is comparatively higher.
and its zooecia apertures, so far as observed, not radially
arranged.

BRYOZOA. 639

PHYLLOPORINA Ulrich.

(For generic diagnosis see page 399.)

After extended study this genus was established for the recep-
tion of a well marked group of Silurian Bryozoa. Nicholson's
Retppora trentonensis, and Hall's R. asperatostriata are regard-
ed as the typical species. The earliest species known belong to
the Chazy group from which horizon I figured .one (PI. LIII,
fig. 4,) that is identified with Hall's Gorgonia? aspera. It is a
peculiar form and differs widely from the ordinary species of
Phylloporina, among which it is now placed with some doubt.
The other species that should be removed to the new genus are
Retepoia trentouensis Nich., Intricaria ivticulata Hall, Phyllo-
pora corticosa Ulr. (Trenton): Intricaria clatbrata M. & D.,
Phrllopora variolata Ulr. (Gin. gr.); Retepora angulata Hall,
(Clinton); and R. asperatostriata Hall. (Niagara). Several new
species are known, one of them (P. dawsoni) is briefly defined
on page 331 and the internal structure very well illustrated on
PL LIII.

PHYLLOPORINA GRANISTRIATA Ulrich.

PL XXIX, Fig. 3-3a.

Zoarium an undulated expansion, consisting of more than
ordinarily rigid, slender branches, from 0.3 to 0.5 mm. in width,
that inosculate at rather long but irregular intervals. Fene-
strules narrow, with an average length of about four mm., but
varying from two to six mm.; width from 0.2 to 0.7 mm. Re-
verse with fine, granulose, longitudinal striae. Celluliferous side
not seen. Zooecia (as observed in sections) tubular, arranged
in three rows. Apertures circular, with a small peristome, 0.09
mm. in diameter, ten or eleven in two mm. Rows of cells sepa-
rated by slightly elevated carinae, bearing one small acantho-
pore to each zooecium.

This species is allied to P. reticulata Hall, and P. dawsoiii.
From the first it is distinguished by the stronger branches and
much larger fenestrules. From the second by the same differ-

640 PALAEONTOLOGY OF ILLINOIS.

ences, and in having three instead of two rows of zooecia. In
the length and form of the fenestrules the species resembles P.
trentonensis Nich., but they differ too obviously in other re-
spects to require any further comparison

Position and locality: (?) Base of Cincinnati group, Alexander
Co., 111. Another specimen was collected by Prof. Moritz Fischer
in the upper beds of the Trenton group at Lexington, Ky.

CHAINODICTYON Foerste, 1887.

(Bull. Sci. Labor. Denison Univ., Vol. II, p. 81.)
(For generic diagnosis see page 399.)

This genus was founded upon a species from the Lower Coal
Measures of Ohio. Its fenestrules and zooecia apertures are
slightly larger than those of the Illinois form, but in all other
respects the two agree very closely. Both greatly resemble the
Retepora, undata McCoy, in having the reverse transversely un-
dulated, and it is not improbable that a careful examination of
McCoy's species will show it to be congeneric with the American
types. The elongate, conical, or subtubular zooecia, their large
impressed apertures, and the thin interspaces, place the genus
into the new family PHYLLOPORINIDJE.

CHAINODICTYON LAXUM var. MINOR Ulrich.

PL LXII, fie. 3-3a.

Zoarium a reticulated foliar expansion, consisting of thin in-
osculating branches, united in such a manner that they leave
irregular lozenge-shaped fenestrules averaging 1.5 mm. in length
by 0.8 mm. in width. The fenestrules are ranged in moderately
regular longitudinal and diagonally intersecting series, with re-
spectively 4.5 and 6 to 7 in 1 cm. each wray. Branches strongly
convex on the obverse side, 0.3 to 0.45 mm. in width, with four
alternating ranges of zooecia. Apertures rather large, ovate-
acuminate, somewhat oblique, arranged in acute diagonal series.
On the reverse face the branches are marked with sub-imbricat-
ing transverse folds or striae, which pass across the flattened
surface of the branches in a curved direction.

BRYOZOA. 641

Tliis variety differs from the typical form of the species in
having smaller, and more regularly arranged fenestrules. The
zooecia apertures also seem to have been somewhat smaller, but
this point was not determined satisfactorily.

Position and locality: Lower Coal Measures, Seville, 111.

ARTHROCLEMA Billings, 1862.

(Palaeozoic Fossils, vol. I. p. 54.)
(For generic diagnosis see page 400.)

ARTHROCLEMA ANGULARE Ulrich.

PI. XXIX. fig. 6. 6b.

Of this species I have seen only isolated segments, but there
can be no question as to their generic relation. The primary
ments are four mm. in length, about one mm. in diameter,
somewhat irregularly cylindrical, with the ends slightly thick-
ened, solid, the proximal extremity obtusely pointed, the upper
only convex and faintly indented at the center. On two oppo-
site sides of the segments there is a large and rather shallow
socket, situated a little below the middle of the length. The
secondary segments are six-sided, 5.5 mm. in length, 0.5 mm.
or very little more in diameter. Zooecia with narrow oval aper-
tures, 0.07 mm. wide, 0.17 mm. long, seven in three mm. ar-
ranged in longitudinal series, between the strong bounding
angles of the slightly concave sides of the segments. The lower
margin of the apertures is more prominent than in front, and
generally drawn out posteriorly. On the primary segment the
zooecia are less regularly arranged, and the interspaces between
the apertures flexuously striate. especially in the vicinity of the
articulating sockets. Tertiary segments not observed.

In most respects the above species agrees with A. pulchelluni
Billings, from the Trenton of Canada. Before me I have a
number of very fine specimens of that species, showing that
both the primary and secondary segments are longer in the
Illinois species, those of the Canadian examples being quite con-
stantly two or three ram. in length. The cells are also a little
smaller and closer together, there being six in two mm.; the
—80

642 PALAEONTOLOGY OF ILLINOIS.

number in the length of a segment varying from four to seven,
generally five or six. One specimen which I collected at another
locality* is clearly distinct from Billings' species. This species I
propose to call A. billings!, in honor of the eminent founder of
the genus. It is distinguished as follows:

The primary segments are 3.5 to 4 mm. in length, and 0.8
mm. in diameter. The first of each of the secondary segments
is also about 4 mm. in length, while the remaining secondary,
and all the tertiary joints, are only 2 mm. long by about 0.5
mm. in diameter. The most striking peculiarity is that each of
the primary segments articulated with four secondary segments,
two upon each side. Compared with A. pulchellum the cell
apertures are more crowded and thin-walled, as well as sub-
quadrate instead of oval, though also six in two mm. The
whole zoarium also has a more rigid appearance than has been
observed in any example of that species. (PL XXIX, fig. 6c.)

HELOPORA Hall, 1852.

(Pal. N. Y. Vol. II, p. 44.)
(For generic diagnosis see page 401.)

The typical species of this genus is Hall's H. fragilis, a very
abundant and characteristic fossil of the Clinton group of Can-
ada. Beside the type species, seven others are known to me
that are constructed upon the same general plan,t four of them
Lower Silurian and three Middle or Upper Silurian. The Lower
Silurian species differ from the Upper Sifurian and typical
section of the genus, in having the cell apertures arranged in
longitudinal series between elevated ridges, and the interspaces
between the ends of the apertures longer. In H. fragilis the
zocecia apertures are oval or sub-quadrate, with rather thin
equal walls. In H. Undstromi, n. sp., they are ovate, with hexa-
gonal margins. The Lower Silurian species are also without
the small acanthopores which are found in the Upper Silurian

*In the city of Ottawa, at the base of the bluffs near the ferry landing.

* In the Catalogue of Silurian Fossils of Anticosti, Mr. E. Billings describes twelve
species, which he refers to Helopora. Upon examination only three of these prove con-
generic with H. fragilis.

BRYOZOA.

643

forms. When the various species now referred to the genus are
better understood, these two sections will probably be separated
generically. A suggestive resemblance to Cyclostomatous Bryo-
zoa is represented by H. imbricatu and H. spiniformis. The in-
ternal structure of two typical species is represented in the ac-
companying cut.

Fig. 18, a, b, c, d, e. Sections of Helopora frag ilis, x!8, Clinton group, Hamilton, On-
tario. Fig. a, tangential section as it appears in the ferruginous matrix; in these ex-
amples the extreme outer region is destroyed; b, tangential section of another exam-
ple, showing acanthopores at surface, etc. ; c, transverse section near upper extremity
of segments; d, same at base; e, vertical section.

Fig. /, a, h, sections of Helopora Kndstromi, n. sp. x!8. Upper Silurian. Gotland;
/, tangential section showing form of zooacia and acanthopores; g, transverse section;
h, vertical section. The cylindrical or slightly club-shaped segments of this fine species
vary in length from 10 to 15 mm., in diameter from 1.3 to 1.8 mm. Upper extremity
flattened, slightly concave centrally; lower end moderately convex. Zooecia arranged
in quincunx: measuring lengthwise seventeen in 5 mm.; diagonally four in 1 mm.
Apertures direct, oval, with a narrow peristome set into a rhomboidal or hexagonal
concave space. Between the ends of the cells a strong acanthopore. It gives me great
pleasure to propose the above name in honor of the talented Swedish Palaeontologist,
Dr. Gustav Lindstrom, to whose kindness I owe the opportunity of studying this beauti-
ful species.

644 PALAEONTOLOGY OF ILLINOIS.

HELOPORA IMBRICATA Ulrich.

PL XXIX, Fig. 5.

Segments with a rough aspect, 3 or 4 mm. in length, and
0.5 mm. in diameter; upper end flattened, lower extremity ob-
tusely pointed and striated. Zooecia in seven or eight vertical
series around the segment, the rows being separated by rather
inconspicuous carinae; also in much more conspicuous trans-
verse series, on an average 0.3 mm. distant from each other.
Apertures when worn, oblong quadrate; in the perfect state ob-
lique, sub-circular or ovate, 0.1 mm. wide, with the lower mar-
gin strongly elevated and produced posteriorly into three small
ridges, the central one terminating at or within the mouth of
the preceding cell, is the most persistent, while the other two,
which continue into its margin, are generally fainter and may
be obsolete. The transvere approximation of the zocecia and
the prominence of the posterior margin impart a characteristic
imbricating appearance to the segments.

This species resembles H. spiniformis Ulrich, from the base of
the Trenton group of Tenn., but is distinguished by the shorter
segments, more pronounced aperture margin, and the ridges
between the ends of the cells.

Position and locality: Cincinnati group. Isolated segments
are not uncommon on the surface of limestone slabs at Wil-
mington, 111.

NEMATOPORA Ulrich.

(For generic diagnosis see page 401.)

The typical and earliest known species of this well marked
and natural group of Palaeozoic Bryozoa is the N. quadrata,
n. sp.,* from the Trenton limestone of New York. The next

* The characters of this species are as follows: Zoarium slender, dichotomously
branched at varying intervals; branches quadrangular, 0.3 or 0.4mm. wide. Zooecia
arranged alternately in four longitudinal series, separated by a double ridge. Aper-
tures oval, 0.4 mm. wide and nearly twice as long, four in 2 mm. lengthwise ; surrounded
by distinct peristome ; peristomes connected longitudinally by a thin ridge. (PL XXIX,
fig. 12.)

The double ridge between the ranges of cells is the most conspicuous peculiarity of
this species. It is common on slabs from Trenton Falls, N. Y.

BRYOZOA. 645

species occurs in the Alexander Co. beds of the Cincinnati group.
(The exact age of these beds is somewhat doubtful, and I am
inclined to regard them as more likely representing an upper
member of the Trenton group). Four species are known and
now described from the horizon. So far as known, the genus is
represented only by an undescribed species in undoubted Cin-
cinnati group deposits, but from the divisions of the Anticosti
group, Billings describes five forms under Helopora that have
the characteristic features of the genus. These are H. concava,
forwosa, Hneata, striatopora. and strigosa. The H. lineopora
may also belong here. Of Niagara species, Hall's Trematopora
mJnuta and one or two undescribed species are congeneric with
JV. quadrat a. As yet the genus is unknown above the Niagara
formation.

NEMATOPORA RETRORSA Ulrich.

PI. XXIX, fig. 9-9b.

Zoarium ramose, sub-cylindrical, branching irregularly, about
0.6 mm. in diameter. Zocecia arranged in longitudinal series,
about 5 in two mm., between eight to ten straight and moder-
ately prominent ridges. Apertures sub-circular. 0.1 mm. in
diameter, slightly truncated, and sloping on the posterior side;
the anterior margin direct, sharp, sometimes with a perceptible
rim. Immediately below the orifice the interspace exhibits three
faint striae. Walls of zocecia very thin, appearing somewhat
sickle-shaped in vertical section.

The backward direction and the subcircular form of the zoce-
cial apertures are characteristic features. In A7, fragilis the
apertures are also directed backwards, but they differ in being
oval, while the longitudinal ridges are less distinct or absent,
and the rows of zooecia only six, instead of eight to ten.

Position and locality: Base of Cincinnati group. Alexander
County, Illinois.

646 PALEONTOLOGY OF ILLINOIS.

NEMATOPORA ALTERNATA Ulrich.

PI. XXIX. flg. 8-8a.

In growth and general aspect this species closely resembles
the preceding, and in the worn condition in which they are
usually found, it is not easy to distinguish them. When in a
good state of preservation, the alternate arrangement of the
cells, absence of longitudinal separating carinae, and other char-
acters shown in the figure, will separate them.

Position and locality: Associated with the preceding.

NEMATOPORA FRAGILIS Ulrich.

PI. XXIX, flg. 10-lOe.

Zoarium ramose, very slender, branching dichotomously or
otherwise; branches 0.35 mm. in diameter. Zooecia in six long-
itudinal ranges, seven in four mm.; ranges not separated by a
ridge, though the branch looks angular when worn. Apertures
ovate, 0.08 mm. in width, twice as long and channeled pos-
teriorly; a faint peristome around the sides and front margins.
In vertical sections the walls are thin and falciform. Trans-
verse section show two minute axial tubes at the center of the
branch.

The six ranges of zooecia suggest a comparison with H. lineata
Billings (PI. XXIX, fig. 7), from the Anticosti group, but we
soon find that they disagree in nearly every other respect. The
species finds closer allies in N. retrorsa and N. alternata but,
when in a good state of preservation, the different form of aper-
ture, smaller size of branches and other characters readily dis-
tinguish them.

Position and locality: Base of Cincinnati group; Alexander
County, Illinois.

NEMATOPORA DELICATULA Ulrich.

PL XXIX, flg. ll-llb.

Zoarium small, exceedingly slender, ramose above the pointed
basal end. Branches quadrangular, each side 0.15 to 0.18 mm.

BRYOZOA. 647

wide. Zocecia in four ranges, with subcircular or ovate aper-
ture, 0.12 mm. in the larii'fst diameter, separated by long in-
tervals, about three in 0.2^ mm. Peristome very faint, often
confluent with the moderately sharp angles of the branches.

The exceeding delicacy, widely separated zooecial apertures,
and quadrangular zoarium of this species, distinguish it from
all other species of the genus, excepting N. quadrata, known to
me. It is too distinct from that form to require comparisons.

Position and locality: Associated with the preceding species
in the Cincinnati group, Alexander County, Illinois.

RHOMBOPORA Meek, 1871.

(Pal. Eastern Nebraska.)

(Orthopora Hall. Pal. X. Y. Vol. VI, p. XIV.)
(For generic diagnosis see page 402.)

Of the Palaeozoic genera of Bryozoa this genus ranks next
in importance to Fenestella and Polvpora, having a known re-
presentation in American rocks of no less than 46 species.
These range through all the important divisions beginning with
the Niagara, where we meet with one species (Trematopora
granulifera Hall). In the Lower Helderberg we have three or
four, in the Upper Helderberg and Hamilton ten to twelve, in
the Lower Carboniferous divisions at least twenty-five, and
in the Lower and Upper Coal Measures five. The general charac-
ters of the genus are maintained throughout with remarkable
persistency, and I cannot mention a single feature, either ex-
ternal or internal, in which the Silurian and Devonian species,
taken as a whole, differ from the Carboniferous forms. It is,
therefore, a little surprising that Hall should propose Ortho-
pora for the reception of the majority of the Upper Silurian
and Devonian forms, since the ground is fully covered by Rhom-
bopora. What is even more astonishing is that Orthopora is
defined as a subgenus under Trematopora when the typical
species of the two groups are not closely related in any respect,
and really belong to different suborders. Even Orthopora as
figured in Vol. VI, N. Y. Pal., contains widely divergent forms.
Acanthoclema is the name proposed by the same authority for
another group of closely related forms. The type species is

648 PALAEONTOLOGY OF ILLINOIS,

marked by longitudinal ridges and a strong spine which is situ-
ated on the depressed space between the ends of the zooecia
apertures. ' A. confluens, of the present work, has these two
essential features, but I very much fear that the division will
prove of little value, as it will be exceedingly difficult to draw
the line between it and Rhombopora. A second group em-
braced by Hall's Acanthoclema are widely different from his
type species, and belong to my genus Streblotrypa. Of these
I may mention A. scutvlatum Hall, and A. hamiltonense Nich-
olson, sp.

RHOMBOPORA SUBANNULATA Ulrich.

PI. XLV, flg. 1-li.

Zoarium dendroidal, branching dichotomously at intervals of
15 mm. or more, and inclining to spread in the same plane.
Branches from 1.2 to 2 mm. in diameter, marked with more
or less noticeable annulations between 1.5 and 2 mm. apart.
Zooecia proceed obliquely out from the axis of the branch at
an angle of about 45°, a,nd have irregularly, flexuous thin
walls. Two or three superior hemisepta and an occasional in-
ferior hemiseptum are seen at the close of the immature region
in vertical sections. The zooecia walls are in contact. In young
examples they are comparatively thin, the apertures sub-rhom-
boidal in shape and arranged in diagonal intersecting series
winding spirally around the branch. Measuring diagonally ten
in 2 mm. At each angle a small but distinct tubercle. As the
zoarium matures, the apertures become smaller and subcircular
or oval in shape, the interspaces thicker, multigranose, and
occasionally form faint longitudinal ridges. Now there are
nine apertures in 2 mm. diagonally.

In transverse and tangential sections the strong hemisepta
cause appearances likely to be mistaken for diaphragms.

This species resembles several others but is clearly distinct.
The superficial appearance, as shown in the figures, varies
greatly according to the age of the examples. With the aid of
tangential sections the extremes are brought together, showing
what may also be seen by examining the opposite ends of large
fragments, that they are really due to age. E. varians, of the
Keokuk group, shows similar variations.

Positition and locality: Hamilton group, Buffalo, Iowa.

BRYOZOA. ' 649

*•

RHOMBOPORA SULCIFERA Ulrich.

PL XLV, Fig. 2-Ub.

Zoarium consisting of slender cylindrical stems, 1 mm. or a
little more in diameter, none of which were observed to branch,
though probably doing so at long intervals. Zocecia apertures
oval, about 0.17 by 0.08 mm., arranged in diagonally inter-
secting series, crossing each other at an angle of about 90°,
with eight or nine in 2 mm., measuring diagonally, and about
six in the same space longitudinally. Interspaces as wide or
wider than the apertures. A considerable number of small
spines encircle the apertures, and are often arranged in a double
series. In the latter case the center of the interspace is de-
— 'd. so that the apertures appear to be surrounded by a
granulose peristome. The distinctness of this furrow, which has
suggested the specific name, depends largely upon the preserva-
tion of the specimen. Beside the small spines, a less numerous
series of larger size are present, generally one between the ends
of the apertures. In tangential sections the small spines are
noticed only in the extreme outer region of the zoarium, while
the larger ones extend inward to a greater depth.

The smaller size of the branches, the depressed interspaces,
and their great thickness in tangential sections, distinguish the
species from R. subannulata.

Position and locality: Hamilton group; Davenport, Iowa.
The specimens were presented to the author by Rev. W. H.
Bams of Davenport. Iowa.

RHOMBOPORA LIXEINODIS Ulrich.

PL XLV, Figs. »-3b. and (?) 4-la.

Zoarium consisting of slender stems from 0.5 to 0.8 mm. in
diameter, branching dichotomously at intervals of from 3 to 6
mm. Surface appearing beaded from the large number of small
spines arranged serially and close together on straight or flexu-
ous, elevated, rounded ridges, running parallel with the length
of the branches between the rows of apertures. In young ex-
amples these ridges are generally more flexuous than in the
-81

650 PALAEONTOLOGY OF ILLINOIS.

larger specimens. Apertures long oval, their longer diameter
about 0.14 mm., the shorter 0.07 mm., alternating in the ad-
joining rows, with six in two mm. longitudinally, and about
five in 1 mm. diagonally.

A variety of this form, or, perhaps, a closely related species,
occurring with it, is represented by figs. 4 and 4a on PL XLV.
Its zoarium has a stunted appearance, caused by the frequent
bifurcation of the branches. The zooecia apertures are shorter,
and there are eight in 2 mm. longitudinally. The granules and
ridges are less marked, and, especially near the base, many of
the zocecia apertures are closed by a thick calcareous deposit.
Should these differences prove constant, the form might be
called jR. humilis.

Position and locality: Upper Helderberg, Falls of the Ohio.

RHOMBOPORA DICHOTOMA Ulrich.

PI. LXX, Figs. 13-13b.

Zoarium dendroid, spread in the same plane, arising from an
expanded base. Branches strong, about 3 mm. in diameter,
dividing dichotomously at intervals of 10 to 15 mm.; angle of
bifurcation about 85°. Surface with inconspicuous elevations,
which sometimes continue around the branch as low annula-
tions. Zooecia apertures arranged in regular intersecting spiral
series, crossing each other at an angle of about 90°. These
lines are somewhat interrupted by the surface elevations, upon
which the apertures are appreciably larger than elsewhere.
Toward the upper ends of the branches the interspaces are ob-
tusely ridge-shaped, the apertures circular, 0.12 mm. in diame-
ter, and situated at the bottom of a rhornboidal sloping area.
The summit of the ridge with a closely arranged series of small
nodes, of which the one at the angles of the rhomb is usually
the largest. Toward the base the diameter of the apertures is
gradually decreased to 0.08 or 0.09 mm., by the thickening of
the interspaces. The latter has also become rounded, and the
nodes a little larger and less regularly arranged. Measuring
diagonally thirteen apertures occur in 4 mm.; longitudinally
seven or eight in the same space.

This species is related to R. lepidodendroides Meek, from the
Upper Coal Measures, but differs in its mode of growth, less

BRYOZOA. 651

prominent large tubercle, and the thickening of the interspaces
with age. R. varians has both smaller zooecia and nodes.

Position and locality: The type specimen is from the Burling-
ton limestone, at Burlington, Iowa. I have collected seven
fragments of what seems the same species from the Keokuk
limestone at Warsaw. 111. A comparison of their internal charac-
ters is necessary before their absolute identity can be admitted.

RHOMBOPORA GRACILIS Ulrich.

PL LXX, figs. 11-116.

Zoarium a long filiform stem, about 1.3 mm. in diameter,
branching dishotomously at intervals varying from 8 to 30
mm. Angle of bifurcation varying between 60° and 90°. The
specimen figured has a total length of 10.5 cm. Zooecia aper-
tures small, oval, 0.1 mm. long, usually arranged in longitudi-
nal and diagonally intersecting series, with six or seven in the
first, and nine in the second, in 2 mm. Interspaces ridge-
shaped, the summit rather sharp, and enclosing an hexagonal
or sub-rhomboidal area which slopes down into the aperture.
A small node may be developed at the angles of junction.

This very neat species differs from R. dichotoma in its more
slender branches, and in wanting the row of nodes on the in-
terspaces. R. exigua is more slender and has granulose inter-
spaces.

Position and locality: Burlington limestone, Burlington,
Iowa.

RHOMBOPORA EXIGUA Ulrich.

PI. LXX. fles. 10, lOa.

Zoarium consisting of very slender cylindrical stems, from 0.6
to 0.8 mm. in diameter. None of the fragments seen are
branched. Zooecia apertures arranged in quite regular, diagon-
ally intersecting, and rapidly ascending spiral series. Also in
less regular transverse and longitudinal rows. Apertures oval,
about 0.11 mm. long, situated at the bottom of the sloping
area, with four in 1 mm. diagonally, and three in 5 mm. trans-
versely. Sloping area narrow, lozenge-shaped or sub-hexagonal,

652 PALEONTOLOGY OF ILLINOIS.

not sharply margined, the summit of the interspace being nar-
rowly rounded and occupied by a row of closely set small gran-
ules. Often two rows of granules prevail for a short distance.

The granulose interspaces and more slender stems separate
this species from R. gracilis with which it is associated. E. at-
tenuata, from the Keokuk group, has larger and more regu-
larly arranged zooecia apertures, and sharply margined areas.

Position and locality: Burlington group, Burlington, Iowa.

EHOMBOPORA ANGUSTATA Ulrich.

PL LXX, figs. 6, 6a.

Zoarium an exceedingly slender cylindrical stem, 0.4 to 0.5
mm. in diameter; not observed to branch, but probably doing
so at long intervals. Zooecia apertures arranged in rather ir-
regular diagonally intersecting series. Sloping area large, elon-
gate elliptical or lozenge-shaped, averaging 0.5 mm. long by
0.2 mm. wide. Summit of interspaces sharp, crowded with a
closely arranged row of small nodes, which form flexuous lon-
gitudinal Knes. Apertures 0.17 mm. long and one-half as wide,
about five in 3 mm. longitudinally. It requires between five
and six zooecia to form one oblique volution about the stem.

The small size of the stems, the comparatively large zooecia,
and the elongate sloping area about their apertures, constitute
the distinguishing features of this species.

Position and locality: Keokuk group. "Rather rare at King's
Mountain, Ky.

RHOMBOPORA INCRASSATA Ulrich.

PL LXX, figs. 12-12d.

Zoarium a rather robust straight stem, from 1.2 to 1.8 mm.
in diameter, occasionally sending off branches of the same size
at about a right angle. Apertures arranged transversely, longi-
tudinally, and in diagonally intersecting series which ascend the
stem spirally, making an angle of about 40° with the axis of
the stem. Interspaces very thick, ridge-shaped, bearing upon
the summit a single or sometimes double series of closely set

BRYOZOA. 653

nodes (? acanthopores) enclosing the sloping area at the bot-
tom of which the aperture is situated. Area deep, oval or sub-
rhombic in outline. Apertures oval, 0.17 mm. long by 0.09
mm. wide, with five in 2 mm. diagonally. About thirteen of
the transverse rows occur in 5 mm.

Thin sections show that the zooecial tubes are arranged in a
wedge-shaped manner about the center, and that the nodes are
really the surface projections of thick-walled tubes.

This species resembles R. dichotomy, of the Burlington lime-
stone, but is distinguished superficially by its larger zooecia,
smaller apertures, and deeper area.

Position and locality: Keokuk group. Not uncommon at
King's Mountain, and Button Mould Knob, n6ar Louisville, Ky.

i ,

RHOMBOPORA VARIANS Ulrich.

PI. LXXI, flg. l-lb.

Zoarium consisting of robust stems, 2 to 4 mm. in thickness,
which arise from an irregularly porous basal expansion, and
usually branch dichotomously at variable intervals. Angles of
bifurcation more or less wide. Zooecia apertures arranged in
diagonally intersecting and longitudinal series, with seven in 2
mm. measuring diagonally, and fifteen or sixteen in 5 mm. verti-
cally. Interspaces decreasing somewhat in thickness from below
upward, and varying considerably in character at the two
extremes, the extent of the variability depending upon the age
of the specimen. On the distal or young portions of the zoarium,
the interspaces are ridge-shaped, with the summit sharply de-
fined and carrying a single series of minute granules. The area
is elongate hexagonal in outline, 0.24 by 0.33 mm., with the
ends truncated, and slopes with moderate rapidity down to the
oval aperture, which has a length of 0.12 or 0.13 mm. Toward
the base the interspaces gradually loose their angularity, the
granules increase in number from one to two, and then three irreg-
ular rows, while the apertures become more nearly circular, and,
near the expanded base of the zoarium, may even be surrounded
by a faint peristome, the interspaces having ere this become
perfectly flat.

Vertical sections show that the primitive or immature region
of the zooecial tubes may be intersected by an occasional thin

654 PALEONTOLOGY OF ILLINOIS.

diaphragm, that the superior herniseptum is strong, and that
delicate diaphragms are often preserved in the vestibnlar region
of old examples. In tangential sections the appearance at differ-
ent stages in the development of the zoarium, as above described,
are easily traced out.

This species is distinguished from R. dichotomy and its Keokuk
representative, by its smaller zooec-ia and the absence of the
strong acanthopores between the ends of the area. This feature
is particularly prominent in the Keokuk examples which I have
provisionally arranged with the Burlington species.

Position and locality: Keokuk group; near Plymouth; near
Whitehall, in Greene Co.; Warsaw and Nauvoo; all localities in
Illinois.

RHOMBOPORA TRANSVERSALIS Ulrich.

PI. LXXI, fig. 4-4b.

Zoarium a comparatively robust stem, 2.5 to 4 mm. in diam-
eter, branching dichotomously, at intervals of 12 mm. or more.
Angle of bifurcation generally about 60°. Young branches com-
monly found flattened from pressure. The surface of the branches
is marked by transverse annulations, about 1.7 mm. apart.
They are formed by the periodic channel-like prolongation of the
anterior end of the depressed areas of transverse series of zocecia
apertures. In old examples, in which the interspaces are thicker
and more rounded than in young specimens, the annulations are
the most distinct, appearing like narrow and slightly depressed
solid bands. In young examples they are much obscured by the
ridge-like prominence of the interspaces, but as their position
is always indicated by a slight elevation of the surface, the
feature constitutes a reliable distinctive character. Interspaces
thick and rounded in the mature specimens, less so, even rather
thin and ridge-shaped in those that are younger; and carrying
from one to three series of small closely crowded granules. De-
pressed areas, (L e., the space bounded by the summits of the
interspaces,) more or less lozenge-shaped, this shape prevailing
especially in young examples. At the bottom of the areas are
situated the ovate apertures, whose long diameter is about 0.12

BRYOZOA. 655

mm. The arrangement of the apertures is not very regular.
The longitudinal series are as a rule more noticeable than the
diagonal rows. The latter intersect each other at an angle of
90° or more. Measuring longitudinally, twelve to fourteen aper-
tures occur in 5 mm.; diagonally 6.5 to 7.5 in 2 mm.

The transverse marking of the branches, and the less regular
arrangement of the zooecia apertures separate this species from
R. vnrmns. Xone of the other are very closely related.

Position and locality: Keokuk group, Plymouth, Xauvoo
and Warsaw. 111.

RHOMBOPORA ATTENUAT * Ulrich.

PL LXX, flg. 7.

Zoarium a slender stem, from 0.7 to 1 mm. in diameter; not
observed to branch. Zooecia apertures arranged very regularly
in longitudinal and diagonal series, which intersect each other
at an angle of about 45°. Interspaces rather thin, acutely ridge-
shaped, bearing upon the summit a single series of very small
and closely set nodes. The node at the angle is commonly larger
than the others. Areas rather narrow, regularly long-hexagonal,
truncated at the ends, sloping rapidly down into the oval aper-
ture, whose long diameter is about 0.15 mm., the shorter 0.10
mm. Longitudinally, there are sixteen apertures in 5 mm.;
diagonally five in 1 mm.

This species is closely allied to R. wortbeni from the Lower
Carboniferous (? Keokuk) deposits of Kentucky. The cells of
that species are a little larger and scarcely so regular in their
arrangement, and the stems stronger, being from 1.2 to 1.8
mm. in diameter. The R. exigua of the Burlington limestone, is
even more slender, has smaller apertures, rounded interspaces,
larger granules, and the ends of the areas pointed instead of
truncate. The last fact causes the diagonal rows of apertures
to ascend more rapidly in their spiral course around the stems.

Position and locality: Not "uncommon in the upper layers of
the Keokuk group at Warsaw, 111.

656 PALAEONTOLOGY OF ILLINOIS.

RHOMBOPORA? ASPERULA Ulrich.

PL LXX. figs. 9— 9e.

Zoarium ramose, growing from an expanded base, attached to
foreign bodies. Stems from 1.0 to 1.6 mm. in diameter, branch-
ing dichotomously at variable intervals. When in a good state
of preservation the surface is very rough or hirsute, the blunt
spines or acanthopores being very prominent, and so abundant
that the zooecia apertures are obscured by them. Apertures
usually suboval, but rather variable in size, shape, and arrange-
ment. Measuring in an obliquely transverse direction, about six
occur in 1 mm. Interspaces rounded, varying in thickness from
one-fourth to three-fourths or more of the diameter of the aper-
tures, depending largely upon the maturity of the specimen.

The irregular arrangement of the zooecia apertures, and the
prominence of the spines, distinguish this species from all others
of the genus known to me. The first peculiarity is so at var-
iance with the ordinary species of the genus that I am inclined
to believe that better sections than I have yet been able to
prepare will show the species to belong to some other genus,
probably Batostomella.

Position and locality: Keokuk group; Keokuk, Iowa, Nauvoo
and Warsaw, 111.

RHOMBOPORA? SPIRALIS Ulrich.

PL LXXI. Fig. 5-5d.

Zoarium a rather robust stem, 1.5 to 2 mm. in diameter, not
observed to branch. Zooecia apertures arranged in diagonal
spiral series which intersect at an angle of between 70° and
80°. Measuring along the series there are five in 2 mm.
The apertures are subcircular, 0.21 mm. in diameter, and
separated by rounded interspaces, bearing a single or double
series of contiguous hollow nodes, which are represented by a
series of minute pores when the surface of the zoarium is
abraded. These pores are quite distinct in thin sections, though
not of uniform size, those in the longitudinal interspaces being
the largest. Transverse sections are interesting because they
show that the zocecia are arranged in a spiral manner about
the axis of the branch. This is a verv unusual feature among
Palaeozoic Bryozoa.

BRYOZOA. 657

The position of this species is doubtful, and more material IB
required before its relations can be determined satisfactorily.
It may turn out to be a Streblotrypa.

Position and locality: Keokuk group, King's Mountain, Ky.

RHOMBOPORA SIMULATRIX Ulrich.

PL LXXI, figs. 2-2e.

Zoarium ramose, branches slender, varying from 1.0 to 2.1
mm. in diameter, dividing dichotoinously at intervals of from
10 to 15 mm. Zocecia apertures oval, averaging 0.12 mm. in
length, arranged in only moderately regular, diagonally inter-
secting and longitudinal series, with sometimes one and then
the other arrangement the most noticeable. Measuring longi-
tudinally, five or six apertures occur in 2 mm.; diagonally, nine
in younger examples and eight in the older ones in 2 mm. In-
terspaces becoming natter and increasing in thickness with age,
usually wider than the zooecia apertures; in the young examples,
narrowly rounded, and crowned with a single series of small,
close set granules, with one of larger size between the ends of
the oval depressed areas. On the larger specimens the inter-
spaces may be nearly flat and occupied by two or three rows of
granules.

The internal characters of a mature example are very well
shown in figs. 2d and 2e.

This species resembles several others but is really not very
closely related to any. Small specimens present external resem-
blance to R. minor, of the Chester group, but the internal struc-
ture of the two is quite different, and points rather to a rela-
tionship with R. wortheni and R. decipiens.

Position and locality: St. Louis group, at Columbia and other
localities in Monroe county, 111.

RHOMBOPORA DECIPIENS Ulrich.

PI. LXXI. flg. 3-3d.

Zoarium ramose, the branches rather robust. 1.5 to 3 mm.
in diameter, divided dichotomously at variable interval*. Zo-
recia apertures oval, a little oblique, averaging 0.15 mm. in
length by 0.10 mm. in width, arranged in more or less inter-
rupted lines, which may be vertical, diagonal, or transverse.
—82

658 PALAEONTOLOGY OF ILLINOIS.

In young examples the arrangement appears to be rather more
regular than in the larger ones. Measuring longitudinally, or
transversely, five or six in 1 mm. Interspaces rather thin,
rounded, not appreciably different in young and old examples,
carrying small tubercles about equal in number to the zooecia
apertures.

Of internal characters those furnished by vertical sections are
the most interesting. (See PI. LXXI, fig. 3c.)

Large examples of this species especially remind one very
much of such TREPOSTOMATA as Batostomella, but thin sections
prove beyond question that it is a true species of Rhombopora,
with close relations to R. wortheni and R. simulatrix. From
the former it is distinguished by the ramose habit of growth,
and much less regular arrangement of the zooecia apertures.
The latter differs in having more slender branches, thicker and
granulose interspaces, and more regularly arranged zooecia
apertures.

Position and locality: St. Louis group. Monroe county, 111.

RHOMBOPORA TABULATA Ulrich.

PI. LXX, fig. 2-2<3.

Zoarium a cylindrical stem from 1 to 1.5 mm. in diameter,
branching dichotomously at intervals of 10 mm. more or less.
Zooecia apertures ovate, overaging 0.18 mm. in length, from
one-half to two-thirds as wide, arranged in irregular series, with
the transverse and diagonal lines less frequently dominant than
the longitudinal. On an average five apertures occur in '2 mm.
transversely, and from twelve to fourteen in 5 mm. longitudin-
ally. Measuring diagonally, seven is the usual number in 2 mm.
Interspaces carinate, as wide or wider than the zooecia aper-
tures, carrying at most of the angles of junction a moderately
large tubercle. Sloping areas varying considerably in form, being
sometimes hexagonal, and at other times pentagonal, lozenge-
shaped, or irregularly quadrate.

Thin sections, aside from showing that the species is rather
closely related to R. persimilis, are interesting because of the
comparative abundance of true diaphragms in the axial or
primitive portion of the zooecia tubes. These and other char-
acters of a vertical section are well shown in fig. 2c.

BRYOZOA. 659

R. persimilis has the zooecia apertures arranged in regular
diagonally intersecting series (about as in fig. 12b, PI. LXX),
the summit of the interspaces granulose when perfect, and the
tubes in the axial region straighter and without diaphragms.
In the Burlington limestone species R. gractiis, the zooecia are
smaller and differently arranged.

Position and locality: Chester group. Rather abundant at
Kaskaskia, 111. Less common at Chester, Illinois, and Sloan's
Valley. Ky.

RHOMPOPORA PERSIMILIS Ulrich.

PI. LXX, fig. 3.

Khombopora persimilis Ulrich, 1884. "Am. Pal. BIT." Jour. Gin. Soc. Nat. Hist. Vol.
VH, p. 30.

The figure above cited represents an unusually large example
of this species, in a slightly abraded condition. The arrange-
ment of the zooecia is as in the typical specimens, only the
apertures are a trifle wider, since, measuring transversely, there
are only five where they show six. This, I believe, is accounted
for by the increased circumference of the larger specimen. Meas-
uring diagonally both show eight in 2 mm., and longitudinally
nine and ten in 5 mm.

Position and locality: Chester group. The specimen here fig-
ured is from Chester, 111., where more typical examples have
also been found in moderate abundance. The species also occurs
at other localities in Illinois, and at Sloan's Valley (Tateville),
Ken tuck v.

RHOMBOPORA MINOR Ulrich.

PI. LXX, fig. 4-4a.

Zoarium irregularly ramose, branches not rigid, from 0.5 to
0.9 mm. in diameter. Zooecia apertures suboval, averaging 0.12
mm. in length, situated at the bottom of the deep and illy de-
fined areas; arranged, generally, in rapidly ascending but not
very regular diagonal series, with about four in 1 mm. Inter-
spaces narrowly rounded, never cariuate. carrying, beside a

660 PALAEONTOLOGY OF ILLINOIS.

single row of small, closely set nodes, some that are of larger
size, and usually situated between the ends of the suboval areas.

Vertical sections are similar to those of R. tabulate, but the
diaphragms seem comparatively more numerous. The zooecial
tubes seem also to be shorter. Externally R. minor differs from
that species in its smaller zooecia and row of closely set nodes
on the interspaces. The zoarium is also much smaller. R. per-
similis has ridge-shaped interspaces, much more regularly ar-
ranged zooecia, and, so far as known, no diaphragms in the
zooecial tubes.

Position and locality: Chester group. Sloan's Valley, and
Litchfield, Ky.

RHOMBOPORA TENUIRAMA Ulrich.

PL LXX. flg. 8-8b.

Zoarium very small, consisting of exceedingly slender stems,
which may divide dichotomously or send off branches at right
angles. Diameter of stems varying between 0.4 and 0.5 mm.
Zooecia apertures oval, about 0.11 mm. long, from one-half to
two-thirds as wide, arranged in longitudinal and diagonally in-
tersecting series, between somewhat flexuous, subangular, longi-
tudinal ridges, which have a more or less irregular appearance
because of the unequal distribution of the two sizes of spines
carried by them. Sometimes the smaller spines are in contact,
at other times widely separated. The areas are more or less
confluent, with the sides rather wide and slightly convex. The
spiral rows of apertures intersect at an angle of about 75°,
and it requires nine or ten of the apertures to make one volu-
tion about the stem. Measuring longitudinally, eleven aper-
tures occur in 4 mm.

The exceeding minuteness of the zoarium, the comparatively
strong spines, and the longitudinal arrangement of the zooecia
between strong ridges, are the distinctive features of this spe-
cies. R. minor is larger, and has the zooecia differently arranged.
R. angustata, of the Keokuk group, has much larger zooecia,
and does not branch at such short intervale.

Position and locality: Chester group. Kaskaskia, Illinois,
and Sloan's Valley, Ky.

BRYOZOA. 661

RHOMBOPORA NICKLESI Ulrich.

PI. LXX. fig. l-lc.

Zoarium consisting of small, dichotomously branching stems,
averaging 0.6 mm. in diameter, but varying from 0.4 to 0.9
mm. Interspaces rather narrow, sloping rapidly down on each
side into the oval apertures, which have an average length of
about 0.17 mm. The summit of the interspaces is narrowly
rounded or sub-angular, and mostly smooth, excepting at the
angles of junction, where it rises into a more or less conspicu-
ous node. On each side of the summit, and marking the top
of the suboval or lozenge-shaped area, there is an exceedingly
minute series of closely arranged granules, which are too small
to be shown in the illustrations. Zooecia apertures ranged in
rather regular diagonal lines, intersecting at an angle of
about 65°: with four in 1 mm. Sometimes the zooecia aper-
tures are narrower on one side of the stem than on the other.

The external appearance of this species is very much like that
of Rhabdomeson rhombiferum Phillips, from the Carboniferous
shales of Scotland, but numerous thin sections show that there
is no axial tube, and that the minute characters agree in all
respects with Rhombopora. R. lepidodendroides Meek, is larger,
and has a single or double row of distinct granules on the sum-
mit of the interspaces between the large spines at the angles.
R. persimilis of the Chester limestone has wider interspaces and
differs internally.

The specific name is given in honor of Mr. J. M. Xickles, of
Sparta, Illinois, to whom we are indebted for the discovery of
this and many other new Bryozoa from the Lower Carbonifer-
ous and Coal Measure deposits of Illinois.

Position and locality: Lower Coal Measures, Sparta, 111.

ACANTHOCLEMA Hall, 1887.

(Pal. N. Y. Vol. VI, p. XV.)
(For generic diagnosis see page 402).

I propose, provisionally, to adopt this genus, for species dif-
fering from typical Rhombopora, in having the zooecia apertures
arranged between longitudinal ridges. Some of the species

662 PALEONTOLOGY OF ILLINOIS.

placed by Hall under his Orthopora,, as also several of my
species of Rhombopora should, perhaps, have been referred
here.

ACANTHOCLEMA CONFLUENS Ulrich.
PI. LXX, Fig. 5-5b.

Zoarium a slender stem, 1 mm. or a little more in diameter,
bifurcating at intervals, frequently found flattened by pressure
in the shales. Zooecia apertures oval, 0.12 mm. long, two-thirds
as wide, arranged very regularly in longitudinal, transverse, and
diagonally ascending series, between sharply angular, and regu-
larly fiexuous, longitudinal ridges, which alternately recede and
approach each other, without, however, at any time coming in
contact. The sloping areas are confluent, 7. e., they communi-
cate with each other by means of a narrow channel which is
left between the ridges. Between this channel and the lower end
of the aperture there is a distinct, though not large tubercle,
that scarcely projects beyond the level of the ridge summits.
Measuring longitudinally, between nine and ten apertures occur
in 4 mm.; diagonally, about nine in 2 mm.; transversely, five
in 1 mm.

None of the species known to me resemble this one sufficiently
to require comparisons.

Position and locality: Keokuk group, Nauvoo, 111.

BACTROPORA Hall, 1887.

(Pal. N. Y. Vol. VI, p. XV.)
(For generic diagnosis see page 402.)

Species of this genus are characterized by a free and un-
branched zoarium, the basal extremity being pointed and the
remainder a simple, slightly curved or straight, solid, cylindri-
cal stem. In their minute features the zooecia and zoarium
differ in no essential respect from Rhombopora. The "solid"
character of the stems distinguishes them from Cceloconus.

BRYOZOA. 663

BACTROPORA SIMPLEX Ulrich.

PI. LXX, flg. 14-14b and PI. LXXI, fig. 6-6a.

Zoarium free, consisting of a simple, unbranched, straight or
slightly curved stem. An average specimen is 1.5 mm. in diam-
eter and 18 mm. long. The largest seen is nearly 30 mm. long
and 1.8 mm. in diameter. The upper extremity is rounded, the
lower is striated and tapers rapidly to a point. Surface with
small, transversely elongated monticules which often appear as
annulations but really never continue more than half way
around the stem, and only rarely more than one-third the way.
These semi-annulations or monticules are developed in two
alternating series on opposite sides of the cylindrical stem.
Those of each series are placed directly above one another, the
distance from summit to summit being about 1.5 mm. Zocecia
apertures oval or sub-circular, about 0.12 mm. in diameter, ar-
ranged in spiral diagonal lines which intersect each other at an
angle of about 67°. Measuring diagonally, nine apertures occur
in 2 mm.; transversely, five in 1 mm. Interspaces seldom equal
in width to the diameter of the apertures, generally considera-
bly less, thickest and less acutely rounded toward the base, the
summit occupied by a single or double row of small closely set
acanthopores, which have a peculiar rayed appearance in tan-
gential sections.

Zooecial tubes thin-walled in the axial region, proceeding from
the center of the stems toward the surface at an angle of about
45°. At the beginning of the peripheral region their walls are
much, though not excessively, thickened. In this zone the
peculiar stellate acanthopores make their appearance. In verti-
cal sections they appear as vertical series of minute dots.

The free and unbranched character of the zoarium of this
species is so marked a feature that complete specimens may
be distinguished at once from associated bryozoa. The trans-
versely elongated monticules are also very distinctive. The
Devonian types of the genus are without surface elevations.

Position and locality: Keokuk group. Abundant at Keokuk,
Iowa; Nauvoo and Warsaw, 111.

664 PALAEONTOLOGY OF ILLINOIS.

OELOCONUS Ulrich.

(For generic diagnosis see page 402.)

This genus, though closely related to Rhombopora and Rhab-
domeson, is amply distinguished by its zoarial and zooecial pe-
culiarities, The free character of the zoarium, its hollow coni-
cal form, and the comparatively short zooecia, are the chief fea-
tures of the genus. So far only two species are known to
have these characters. In Bactropora Hall, the zoarium is also
free, but neither conical nor hollow, the entire axial region of
the cylindrical stems being occupied by the tubular primitive
portion of the zooecia.

CCELOCONUS RHOMBICUS Ulrich.

PI. LXXII. fig. 4-4o.

Zoarium a hollow elongate-obconical body, 8 to 10 mm. long,
and about 1.5 mm. wide across the open top; lined on the
inner side with a thin epitheca. Thickness of the zoarial crust
about 0.2 mm. Zooecia apertures differently arranged on differ-
ent portions of the surface. Near the pointed base they are
narrow and ranged between raised longitudinal lines, which give
this portion of the zoarium the appearance of being striated.
Farther up they gradually become suboval, occupy the bottom
of sharply defined rhombiform sloping areas, arranged in rather
regular diagonally intersecting series. Toxvard the upper end
the areas gradually change from rhombic to regularly elongate
hexagonal, with the ends acute. At the same time an arrange-
ment of the areas in transverse series becomes evident. The in-
terspaces are rather thin and, in the usual state of preservation,
(in which the summit alone projects above the infilling matrix)
appear very delicate. At the angles of junction the summit is
slightly elevated. Measuring longitudinally, about six zooecia
apertures occur in 2 mm.; diagonally, five in 1 mm.; trans-
versely, five in 1 mm.

Thin sections show that the zooecial walls are comparatively
thin throughout, that the zooecia are short, ranged in longitu-
dinal series on the basal plate, and provided with both hemi-
septa, the inferior one but little developed.

BRYOZOA. 665

The conical form of the zoarium distinguishes this form from
all the Lower Carboniferous Bryozoa, known to me, except-
ing the next described.

I am indebted to Mr. J. M. Nickles for the only specimens
seen of this species.

Position and locality: St. Louis group; Fountain Creek, Mon-
roe county, Illinois.

QELOCONUS GRANOSTJS Ulrich.

PL LXXIL Fig. *-3b.

Zoarium elongate cone-shaped, hollow, with a rather thick,
transversely striated epithecal lining, apparently perforated by
minute tubuli. Thickness of entire zoarial crust about 0.3 mm.
Cone from 8 to 12 mm. long, and from 1.3 to 2 mm. wide
across the open top. Base attenuate, usually deflected a little
to one side. Zooecia arranged as in C. rhombicus, but with the
interspaces higher, granulose, and the summit more rounded;
the area more abruptly impressed, deeper, and not so sharply
outlined, appearing, in the lower two-thirds of the zoarium, to
be rather of oval shape than rhombic. Apertures varying from
oval to sub-circular, 0.1 mm. in diameter; measuring longitudi-
nally, there are between six and seven in 2 mm.; diagonally'
between four and five in 1 mm.; transversely, five and often six
in 1 mm.

Of internal characters, the most striking is the strength of
the basal lamina and zooecia walls when compared with C.
rhombicus.

Position and locality: Chester group; near Anna, Union Co.,
111.

STREBLOTRYPA Ulrich.

Acanthoclema Hall (pars). Pal. N. T., voL VI, 1887.

(For generic diagnosis see page 403.)

In its superficial characters the typical species of this genus
greatly resembles species of D'Orbigny's Cavea (C. costata, et
regularis) ,but whether this resemblance is due to real relation-
ship, or is only incidental, remains to be seen. Compared with
—83

666 PALEONTOLOGY OF/ ILLINOIS.

Rhombopora, the principal difference is found in the more or
less numerous pores which (normally) are situated back of the
zooecia apertures.

The Devonian species of the genus Hall has placed under his
new genus Acanthoclema. They are, however, quite distinct
from his A. alternation, which is mentioned as the type, and
which is closely related to Rhombopora.

STREBLOTRYPA MAJOR Ulrich.

PI. LXXI, fig. 8-8d. and PI. LXXII, fig. l,la.

Zoarium a comparatively robust, dichotomously or otherwise
dividing stem. Often found flattened from pressure. The divi-
sions of the branches occur at long intervals and are often
unequal. Zooecia apertures oval, 0.25 mm. long and about 0.15
mm. wide, surrounded by a narrow sloping area, only notice-
able in perfect specimens; arranged in longitudinal series (inter-
rupted at more or less frequent intervals) between subangular
longitudinal ridges, that are not distinct from the aperture
margins but form their lateral boundaries. The longitudinal in-
terspaces between the succeeding zocecia apertures exhibit the
mouths of from one to three short ranges of mesopores. These
pores vary considerably in size, and in number from three to
twelve, but when the zooecial arrangement is regular, their num-
ber is generally either four or six. Measuring longitudinally,
about ten zocecia apertures occur in 5 mm.

Of internal characters, the comparative shortness of the zoce-
cial tubes, the non-development of an inferior hemiseptum, and
the rather irregular appearance of the tubes in the axial region,
are the most noteworthy.

The large zocecia and rather robust zoarium easily distinguish
this species from all others of the genus so far known.

Position and locality: Keokuk group; King's Mountain, Ky.;
Keokuk, Iowa; Nauvoo and other localities in Illinois. The
specimens from Illinois are larger than those from Kentucky.

BRYOZOA. 667

STREBLOTRYPA RADIALIS Ulrich.

PI. LXXH, fig. 2-2d.

Zoarium consisting of slender, dichotomouslj dividing stems
about 1 mrn. in diameter, the whole forming a bushy mass
growing from a central point out in all directions. Zooecia aper-
tures small, suboval, slightly truncated posteriorly, about 0.1
mm, long, two-thirds as wide, occupying the anterior half of
the bottom of a sloping area. Area hexagonal in outline, trun-
cated at the ends, about 0.28 mm. long, by 0.14 mm. wide,
sloping gradually down into the aperture, which, as has been
said, occupies the anterior half of the bottom. The posterior
slope is more gentle than the anterior, and presents the mouths
of from two to four very minute pores, which, unless the speci-
mens are exceptionally preserved, are liable to be overlooked.
The areas are ranged in very regular longitudinal and diago-
nally intersecting series, with eleven or twelve in 3 mm. longi-
tudinally, and six in 1 mm. diagonally. The summit of the
zigzag ridges formed by them is rather sharply defined and
carries a crowded series of very minute granules.

The internal characters are very well shown by the illustra-
tions. The chief distinctive feature shown by thin sections is
the radial arrangement observed in transverse sections.

This species presents much superficial resemblance to Rhombo-
pora attenuata, but a close comparison shows that they differ
in important particulars. Of these the presence of small pores
back of the zooecia apertures in the present species, is the prin-
cipal one. The apertures are also smaller and not situated in
the middle of the area. S. subspinosa, of the Chester limestone,
differs slightly in its measurements, has the areas less sharply
defined, and the ridges somewhat tuberculated.

Position and locality: Keokuk group, near Xauvoo, 111., and
Bentonsport. Iowa.

STREBLOTRYPA NICKLESI Ulrich.

PL LXXI. fles. 9-9c.

Zoarium consisting of slender, sub-cylindrical, bifurcating
stems, about 0.5 mm. in diameter. Zooecial tubes very long.

668 PALEONTOLOGY OF ILLINOIS.

small, almost vertical in the middle of . the axial region, ap-
proaching the surface slowly, and increasing in size a.t the same
time. Between 0.2 and 0.3 mm. from the aperture a short
inferior hemiseptum is developed. Zocecia apertures ovate,
slightly truncated posteriorly, 0.08 mm. long by 0.06 mm.
wide, surrounded by a thin peristome highest at the anterior
border. They are arranged in alternating longitudinal rows
between thin ridges which unite with the peristomes and are
about 0.1 mm. apart. The interspaces between the succeeding
apertures is depressed and occupied by the mouths of from nine
to fifteen small pores arranged in two or three rows. Measuring
longitudinally six zooecia apertures occur in 2 mm.; diagonally
five in 1 mm. It requires about twelve rows to encircle the
stem.

The small zooecia apertures, their regular arrangement, and
the large number of the (?) mesopores. are the distinguishing
features of this species.

The specific name is given in honor of Mr. J. M. Nickles, of
Sparta, 111., to whom belongs the credit of first finding the
species in abundance.

Position and locality: Chester group. Common at Kaskaskia
and other localities in 111., and at Sloan's Valley, Ky. Accord-
ing to Mr. Vine (Proc. Yorksh. Geol. Soc., vol. VIII, p. 107,
1885,) also in the Carboniferous shales of England.

STREBLOTRYPA SUBSPINOSA Ulrich.

PI. LXXI, figs. 7-7a.

Zoarium consisting of long, slender, cylindrical stems, 0.7 or
0.8 mm. in diameter, branching dichotomously at varying in-
tervals. Zooecia apertures arranged alternately in longitudinal
series, nine or ten in 3 mm.; diagonally five in 1 mm. Between
the series are nearly straight longitudinal ridges carrying a
variable number of small nodes. Between the ends of the de-
pressed apertures, which occupy the bottom of distinct oval
sloping areas, there are from two to four small mesopores.
These sometimes occupy the transverse ridges, at other times
the posterior slope of the area.

BRYOZOA. 669

This species is closely allied to the S. radialis, of the Keokuk
group, but differs in having the longitudinal ridges straighter
and nodose, the area oval instead of hexagonal, the mesopores
less regularly situated and often placed on the transverse ridges
instead of within the area.

Position and locality: Chester group. Not uncommon at
Chester, 111., and Sloan's Valley, Ky.

STEBLOTRYPA DISTINCT A Ulrich.

PI. LXXI. flg. 10-106.

Zoarium consisting of slender dichotomizing stems, from 0.5
to 0.7 mm. in diameter. A small slab is almost made up of
fragments, from which we may judge the zoarium formed bushy
masses. Zooecia apertures generally arranged in longitudinal
series, but there are no ridges between the rows. Occasionally
a transverse arrangement will predominate, and, more rarely,
diagonally intersecting rows are formed. On the whole the arrange-
ment is inclined to be irregular. On an average eight occur in
2 mm. Apertures oval, 0.10 or 0.11 mm. long, by 0.07 or 0.08
mm. wide, with the margin somewhat elevated. Interspaces
slightly depressed, varying considerably in width, occupied by
more or less numerous, small but unequal mesopores. The in-
terspaces between the sides of the peristomes are usually linear.

The rather irregular arrangement of the zooecia and mesopores,
and the absence of longitudinal ridges, give this species a very
distinctive and characteristic appearance.

Position and locality: Chester group. Chester, 111.

WORTHENOPORA Ulrich.

(For generic diagnosis see page 403.)

WORTHENOPORA SPINOSA Ulrich.

PI. LXVm. Fig. l-lg.

Zoarium a bilaminar elongate frond, 3 or 4 mm. wide, 0.5 to
0.8 mm. in thickness, branching dichotomously or otherwise at
long intervals. Acutely elliptical in cross section. Margins sub-

670 PALAEONTOLOGY OF ILLINOIS.

parallel, armed with a series of slender spines from 0.3 to 0.5
mm. long, pointing obliquely upward and outward. There are
on each side about sixteen in 3 mm. Zooecia enclosed by an
elevated sub-a,ngular ridge, common to adjoining zooecia. The
space enclosed is elongate, somewhat rhombic in shape, drawn
out long wedge-shaped posteriorly, and more rounded anter-
iorly; the whole usually 0.6 mm. long and 0.12 mm wide.
Aperture semi-elliptical, truncated posteriorly, 0.18 mm. long,
and 0.1 mm. wide, occupying the anterior third of the space
enclosed by the ridges, which form its margin except at the pos-
terior side, where a thinner and less elevated line separates the
aperture from the remainder of the enclosure. The latter forms
an irregular sub-triangular depressed space, with the bottom
smooth and slightly concave. When perfect five small tuber-
cles, one on the posterior and two on each of the lateral mar-
gins, project into the aperture. Apertures arranged in regular,
acutely intersecting, diagonal series, nine in 3 mm., and in less
regular transverse rows, between eight and nine in 2 mm. The
marginal rows of zooecia are usually a little larger than the
central ones.

Position and locality: Keokuk group. Warsaw and Nauvoo,
111.; Keokuk and Bentonsport, Iowa; Warsaw beds, at War-
saw, 111.

WORTHENOPORA SPATULATA Prout.

PI. LXVIII figs. a-2a.
Flustra spatulata Prout, 1859. Trans. St. Louis Acad. Sci. vol 1. p. 446. PI. 17, fig. 2-2c.

This species differs from W. spinosa mainly in the form of
the zoarium which is always more explanate, being usually of
flabellate form. The margins are sharp and striate, and with-
out spines. On one fragment many of the triangular suboral
spaces are divided in half by a thin transverse ridge.

Position and locality: Warsaw beds, Warsaw, 111., and Bar-
rett's Station, St. Louis county, Mo.

BRYOZOA. 671

CYCLOPORA Prout, 1860.

(Trans. St. Louis Acad. Sci. vol.1, p. 574.)
(For generic diagnosis see page 403.)

The utmost confusion has hitherto prevailed among palaeon-
tologists who have sought to determine the true characters of
this genus. Such a condition of affairs appears natural enough,
when we consider that according to Prout's description the
principal feature of the genus is the concentrically and radiallv
striated epithecal membrane ("sole"). The zooecia are said by
him to be sub-tubular, sub-prismatic, and separated by a po-
rous interstitial net-work. The last character in conjunction
with the preceding, suggests Fistulipora, but, when we examine
his species, none of them show anything like the interstitial
net-work of that genus. On the contrar}-. none of his original
species, excepting C. fungia. which, being the first described, I
regard as the type, have any interstitial cells whatever. C. fiin-
pia too, when normally developed, has only a depressed space
back of the zocecia aperture, which as growth proceeds is grad-
ually drawn out into a tabulated mesopore. Four species are
described by Prout, and these in themselves already show how
extremely misleading an index to generic affinity is the com-
mon possession of a striated epitheca. Thus C. discoidea differs
so much from C. fungia in its zooecial features that I propose
the new genus Proutella for it; C. polymorpha is a true Steno-
pora, and probably identical with his Flustra tuberculata; and
C. jamesi is the same as Ptilodictya pavonia D'Orb.

The genus as now defined is based upon specimens that were
identified by Dr. Prout himself with his C. fungia. It is still
somewhat unsatisfactory, and much more work is necessary
before the true position of the genus can be established.

CYCLOPORA FUNGIA Prout.

PL LXVm, figs. 3-3e.

Cydopora fungia Prout, 1860. Trans. St. 'Louis Acad. Sci. vol. 1, p. 577.
Cyclopora fungia Prout, 1866. Geol. Surv. HI. vol. n, p. 419, PL 22, flgs. 9-9b.

Zoarium an irregularly undulating sub-circular expansion, 3
mm. or less in thickness, and from 2 to 7 cms. wide. Under

6 72 PALAEONTOLOGY OF ILLINOIS.

surface with an epithecal membrane, marked with irregular con-
centric wave-like wrinkles and faint radiating- lines, the latter
being the base of the zocecia walls showing through; at the
center there is a slightly raised or depressed cicatrix of attach-
ment, about 5 mm. in diameter. Upper surface occasionally
even, generally with more or less elevated monticules, composed
of cells wider apart and rather larger than the average. Zoce-
cia for a short distance prostrate and thin-walled, then making
a rather sharp curve, proceed direct to the surface; the walls
have now become thicker and a number of mesopores devel-
oped, which may be intersected, according to age, by from one
to four or more centrally perforated thick diaphragms. The
zooecial walls exhibit a large number of delicate transverse
lines, which may represent minute connecting foramina. Some
of the zooecia also show several tooth-like processes projecting
a short distance into the vestibular cavity. These denticles
seem to have been developed at successive levels, perhaps in all
the zooecia. Apertures sub-circular, the posterior side usually
somewhat straightened, averaging 0.15 mm. in diameter, sur-
rounded by a thin and but little elevated peristome, that, some-
times at any rate, carries a number of very small granules.
Between the monticules they are arranged in quincunx, thus
forming transverse, longitudinal and diagonally intersecting
rows, whose regularity is more or less disturbed around the
monticules. The triangular or oblong quadrate space left be-
tween the apertures is occupied by one or two mesopores, either
open or closed by a membrane.

Three specimens give the following measurements:
No. 1. Transversely, 11 apertures in 3 mm.

Eleven of the transverse rows in 3 mm.

Diagonally, 10 apertures in 3 mm.

Total number of apertures in 3 mm. square, 121.
In this specimen the interspaces between the apertures are
triangular as in fig. 3d. It is from the Keokuk limestone, at
Keokuk, Iowa.
No. 2. Transversely, 9 apertures in 3 mm.

Fourteen of the transverse rows in 3 mm.

Diagonally, 12 apertures in 3 mm.

Total in 3 mm. square, 126.

BRYOZOA. 673

In this specimen the interspaces are long and narrow. It is
from the base of the "Warsaw beds, at Warsaw, 111.
No. 3. Transversely. 7.5 apertures in 3 mm.

Sixteen of the transverse rows in 3 mm.
Diagonally, 12 apertures in 3 mm.
Total number in 3 mm. square, 120.

In this specimen the interspaces are wider and shorter than
usual. Its surface is represented by figs. 3-3b. Keokuk group,
Xauvoo. 111.

Position and locality: A common species in the Keokuk and
Warsaw beds at mam- localities in Illinois and Iowa.

CYCLOPORA EXPATIATA Ulrich.

PL LXVm, fig. 4-4d.

Zoarium a very large unilaminar expansion, from 0.5 to 1
mm. thick; one specimen before me (incomplete) has a breadth
of 15 cms. and a width of 8 cms.; occasionally incrusting,
usually free, with the under surface protected by an epithecal
membrane more or less~rugosely wrinkled in an irregularly con-
centric manner. The wrinkles are crossed by faint radiating
lines. Surface with scarcely elevated monticules, composed of
small aggregations of mesopores and a few zooecia of larger
size than the average. Zooecia apertures subcircular, 0.2 mm.
in diameter, not very regularly arranged, ten or eleven in 3
mm., often completely isolated by the large, irregularly shaped
mesopores, but usually in contact with each other at one or
more points. A thin peristome, carrying from four to eight
nodes (?acanthopores) surrounds the apertures. In thin sections
the walls are thin and exhibit considerable variability of struc-
ture, probably indicative of developmental stages, the sequence
of which has not been determined. Sometimes the transversely
lined structure shown in fig. 3e, PI. LXVIII, is quite distinct, but
usually the appearance is more like whatsis shown by figs. 4-4c
of the same plate. Several diaphragms intersect the zooecial
tubes in vertical sections.

This species differs from C. fungia,, in the larger size of the ex-
pansion, the well developed acanthopores, and less regular ar-
rangement of the zocpcia. Tangential sections of the two look
quite different.
—84

674 PALEONTOLOGY OF ILLINOIS.

Position and locality: Keokuk group. Warsaw and Nauvoo,
111.

PROUTELLA Ulrich.

(For generic diagnosis see page 403.)

This genus approaches very near to some of the CHILOSTO-
MATA, but agrees with the CRYPTOSTOMATA in having the zooecia
layers follow each other in direct sequence so as to form tubes.
Proutella furnishes a powerful argument in favor of the view
published in my "American Palaeozoic Bryozoa" as to the func-
tions or purpose of diaphragms.

PROUTELLA DISCOIDEA Prout.

PI. LXIX, fig. 4-4d.
Cyclopora discoidea Prout, 1860. Trans. St. Louis Acad. Sci., Vol. 1, p. 578.

Cyclopora discoidea Prout, 1866. Geol. Surv. 111., Vol. II, p. 420, PI. XXII, fig. 10-
lOa, and PI. XXI, fig. 2-2a.

Zoarium a thin sub-circular expansion, several cm. in diame-
ter, and less than 1 mm. in thickness. Lower or epithecal sur-
face convex, with a short peduncle at the center, and around it
more or less strong concentric undulations or sharp wrinkles;
crossing these there are fine radiating stria', which correspond
with the arrangement of the zooecia, as is shown by the appli-
cation of moisture, when the oblong procumbent portion of the
zooecia is brought to view. Upper or celluliferous surface more
or less concave, with the rhombic or hexagonal zocecia arranged
in very regular curved intersecting lines, about nine in three
mm. Apertures a little oblique, rounded or sub-rhomboidal,
about 0.28 mm. in diameter, of nearly uniform size throughout;
occasionally preserving a delicate membrane, which closes some-
what more than one-half of the opening, the orifice left being
sub-triangular in form and situated at the anterior or depressed
side of the aperture. Interspaces ridge-like, with the angles a
little elevated. As shown by vertical sections, the short zooecial
tubes run from the basal membrane to the upper surface with
a gradual curve, without, however, becoming direct at the aper-
tures. According to the thickness of the expansion, each tube
exhibits from one to four incomplete diaphragms, which spring

BBYOZOA. 675

at a right angle from the posterior wall and extend to a point
a little further than midway to the opposite wall. The inter-
vals between them about equal the diameter of a zooecium.
These incomplete diaphragms may also be detected in tangen-
tial sections.

Prout's description and figures of his Cyclopora discoidea, leave
so much unsaid that I found it quite impossible to identify the
species with certainty. As, however, several of the specimens
used in drawing up the above diagnosis of the species were so
named by Dr. Prout himself, I feel reasonably confident that
they are the same as the original examples. Three outwardly
very similar yet very distinct species, the Cyclopora fungia
Prout, Cycloporella spinifera Ulr., and the present species, are
associated in the Keokuk limestone at Warsaw and other locali-
ties in the State. The difficulty of separating them is greatly
aggravated by the fact, that in perhaps nine cases out of ten,
the specimens show only the under side. Here they look de-
cidedly alike and it was only after considerable practice that I
could separate them successfully. Thin sections will, of course,
immediately distinguish the species, while there is also very
little difficulty in separating specimens showing the celluliferous
side.

Position and locality: Keokuk group. Warsaw, Hamilton,
and Nauvoo, Illinois, and Keokuk, Iowa.

CYCLOPORELLA Ulrich.

(For generic diagnosis see page 404.)

This genus is founded upon C. spinifera. Provisionally I place
another species here, though fully aware that it is widely differ-
ent from the type.

CYCLOPORELLA SPINIFERA Ulrich.

PI. LXIX, fig. 1-lc.

Zoarium discoidal, thickness 1 mm. or less. Under surface
nearly flat, witli a small central elevated scar of attachment;
epitheca showing faint concentric wrinkles and radiating striae.
Upper surface strongly spinulose, sometimes witli smooth spots,

676 PALAEONTOLOGY OF ILLINOIS.

at irregular intervals, consisting of clusters of mesopores. Zo-
oecia apertures obscured by the projecting acanthopores, sub-
angular, 0.15 mm. in diameter, with those in the immediate
vicinity of the "maculae" of much larger size, the largest being
about 0.28 mm. in diameter. The arrangement is in irregular
series with nine or ten of those in the intermacular spaces in 2
mm. Mesopores numerous, of unequal sizes, irregularly distri-
buted, never isolating the zocecia, and much obscured by the
acanthopores. The latter are large and slightly exceed the zo-
oecia in number.

From thin sections we learn that the zocecia are at first pros-
trate and thin-walled, then bending abruptly proceed direct to the
surface. The walls become thickened and apparently amalga-
mated, the mesopores and acanthopores are developed, and, at
intervals of about 0.1 mm., several superior hemisepta will be
seen, in vertical sections, to project from the posterior wall into
the zooecial cavity. The cavity of the acanthopores is compara-
tively large and crossed by closely set, delicate diaphragms;
their walls are composed of obliquely laminated tissue. The
mesopores appear largely filled by a structureless deposit in
which an occasional diaphragm may be detected.

When the under surface alone is visible the species might be
confounded with Proutella discoidea. A little moisture applied
to the epitheca will show that that species has larger cells, the
radiating lines being farther apart. The under surface of Cyclo-
pora fungia is strongly wrinkled; that of Cycloporella? perversa
even more so.

Position and locality: Keokuk group, Warsaw, 111.

CYCLOPORELLA ? PERVERSA Ulrich.

PI. LXIX. flgs. 5-3b.

Zoarium a free or parasitically attached, thin, irregular ex-
pansion, 8 to 10 cms. in diameter, and from 0.5 to 2.0 mm. in
thickness, being often composed of two or three superimposed
layers. When free the lower surface is strongly wrinkled, the
zoarium appearing sometimes like a crumpled piece of cloth.
Zooecial tubes with a short prostrate region, bending soon to
proceed direct to the surface; intersected by one or two dia-
phragms in each layer. Walls moderately thickened, composed,

BRYOZOA. 677

near the surface, of a dark ring of tissue immediately surround-
ing the cavities and a central lucid region (see fig. 3a) . Meso-
pores few, generally small, situated mainly at the angles, often
wanting over considerable spaces. A few small acanthopores
present. Apertures angular or sub-circular, subequal, arranged
in moderately regular curved rows, about 0.15 mm. in diameter,
with nine in 2 mm.

The position of this species is doubtful. In many respects the
Silurian genus Leptotrvpa is suggested, but the presence of
mesopores, argues against a reference to that genus. The
mesopores again are sometimes arranged as in Cyclopora fungia,
but the primitive portion of the zooecia and the structure of
their walls is different. The majority of the characters known
point to the TREPOSTOMATA rather than to the CRYPTOSTOMATA,
but till more material can be studied it has been deemed best
to arrange the species as above.

Care must be exercised in separating the species from the
laminar form of Stenopora tuberculata Prout, which occurs
abundantly at the same locality. When the lower surface alone
is visible, thin sections are generally required to distinguish
them. They, of course, do so effectually.

Position and locality: Keokuk group. Warsaw, 111., Greene
Co., 111., and Bentonsport, Iowa.

078 PALEONTOLOGY OF ILLINOIS.

ADDENDA

ISOTJIYPA (? TECTULIPORA) GOTHLANDICA 11. Sp.
PI. LIV, fig. 6, Gc.

Zoarium irregularly infundibular, about 2 cm. in height and
the same in diameter at open upper end; base small. The zoar-
ium consists of a double network; its entire thickness is about
1 mm. Zocedal apertures on the outer side of the inner net-
work, invisible from the surface because of the great develop-
ment of the carinse and scalae prevailing in genera of this type,
and which form the false or non-celluliferous outer network.

On the inner or "reverse" face of the zoarium the branches
average a little less than 0.3 mm. in width, are flexuous, and
seem to inosculate regularly, leaving oval fenestrules nearly as
wide as the branches; 15 fenestrules, measuring longitudinally,
in 1 cm.; 19 or 20 branches in 1 cm. transverely; surface of
branches striate.

Obverse side with the carinse very strongly developed, their
summits expanded and connected transversely by scalse, two-
thirds as thick, at intervals equalling the development of the
true dissepiments, which always occur almost directly beneath
them. Outer surface of scalse and summits of carinse but little
convex, and marked with from three to five distinct parallel
lines, causing the two exposed faces of the zoarium to resemble
each other greatly. The only difference likely to be noticed is
that on the outer side the false fenestrules and branches are
respectively a little larger and thinner than on the inner face.

Zooecia in two flexuous ranges on each branch, one on each
side of the carina, with 21 or 22 in 5 mm.; apertures subcircu-
lar, 0.1 mm. in diameter, with rather strong peristome.

BRYOZOA. 679

< )\rr the basal portion of the zoarium the false outer fene-
strules are closed, and the entire space within apparently filled
with vesicular tissue.

This species is closely allied to Fenestella ambigua Hall, from
the Niagara shales of Indiana and New York. Its proportions,
however, are somewhat smaller, there being only 10 fenestrules
and 10 to 18 branches in 1 cm. in the American species. In the
latter the outer or false fenestrules are also less regular.

The propriety of placing species of this kind with Isotrypa is
questionable. If the presence of pores on the reverse side of
the dissepiments is essential, and we are inclined to admin the
point, then they must b:? placed elsewhere. Originally we in-
tended to refer the two species to Loculipora, but since seeing
figures of the types of that genus we have concluded that they
cannot properly go there. Unitrypa, also, was suggested, but
we believe that that name should be restricted to forms having
the scalre more numerous than the dissepiments. Hall's recently
proposed Tectulipora (41st Ann. Kept. X. Y. St. Mus., 1888),
is p-obably nearer the mark than any of those mentioned. The
description, however, fails to fit the two species in one point,
and that is in the statement that the carina? continue over the
dissepiments, thus leaving only perforations through the fronds
and no median longitudinal channels. These exist not only in
the Gotland species, but also in the Niagara and a Hamilton
species from Michigan. As the point is one that is not easily
determined, it is possible that the objectionable statement is
founded upon faulty observation. Until more is known of the
type of Tectulipora. and its character fully illustrated, we must
be content with referring to the fossils under consideration as
above.

Position and locality: Upper Silurian, Island of Gotland.

We are indebted to Prof. Gustav Lindstrom for the oppor-
tunity of describing this interesting species. The type is in the
author's collection.

About the time the text of this volume had been put into
type (Dec. 1st, 1889), Mr. S. A. Miller's valuable work on
''North American Geology and Palaeontology'' appeared. A list
of the new genera and species described in this volume had
previously been transmitted to him, together with a revised

680 PALAEONTOLOGY OF ILLINOIS.

catalogue and classification of American Palsezoic Bryozoa,
which we had prepared, but could not, because of a lack of
space, publish with the more necessary portion of our MS. on
the Bryozoa. Mr. Miller, however, chose to arrange the Bryo-
zoa according to his own views, adopting some of the new-
families, and nearly all the new genera and species. We do not
complain of this, since he had an undisputed right to use the
material" turned over to him in whatever way he saw fit. We,
on the other hand, have equally as good a right to dissent
from the arrangement he has adopted, and we propose to ex-
ercise this right by offering the following critical notes on the
more important points upon which our views deviate.

On page 169 he places the MONTICULIPORID^E and STELLIPORID.E
under_the sub-class ALCYONARIA, the first comprising the genera
Dekayia, JJekayella, Diplotrypa, Monotrypa, Monotrypella,
Monticulipora, NebuHpora, Nyctopora and Prasopora, while
Stellipora alone is included in the second; and on the preceding-
page we find Ptychonema (Hall) under the sub-class Zoantharia,
in the family CHETETID.E; on the whole an arrangement that is
unwarranted, and in the last instance at any rate also mis-
leading, since Ptychonema cannot be distinguished, upon any
grounds knowrn to us, from the earlier Monotrypa.

It is somewhat surprising to find Nyctopora (Nich.), a coral
with relations to Columnaria, placed among the MONTICULIPORID^E.
With the exception of this genus, all the genera referred by
him to the family should be removed to the Bryozoa. If they
are not Bryozoa, then the AMPLEXOPORID.E, BATOSTOMELJ,ID.E,
BYTHOPORID.E, CERAMOPORHXE, FISTULIPORID.E, HELIOTRYPID^E,
PTILODICTYONID.E, RHABDOMESONTID^, andTREMATOPORm^E, all of
which Mr. Miller refers to the Bryozoa, are not either. Extensive
comparative studies show beyond question that these are all so
intimately related that they cannot possibly be divided into
coral and bryozoan groups without doing actual violence to
natural affinities.

As to Stellipora and Constellaria, which Mr. Miller considers
as synonymous, they were placed already many years ago
among the Bryozoa by such authorities as d'Orbigny and Jules
Haime. A superficial comparison with Jurassic and Cretaceous

BRYOZOA. 681

CERIOPORID.E (e. g. Radiopora) should suffice in showing that
that is where they belong.*

On page 290 and 291, we find the classification into families
adopted by Mr. Miller. We will review it in the alphabetical
order in which he arranges the divisions.

The ACANTHOCLADIID.E include the same genera as on pages 397
and 398 of this volume, excepting that Pinnatopora Vine, is
not recognized and Glauconome retained instead.

On pages 614 and 615 we give reasons for using Vine's genus
instead of Glauconome for such species as we place under it in
this volume. Glauconome can not be used for them for two
reasons: (1) As originally defined in Goldfuss' work the name
is synonymous with the previously defined Vincularia of Defrance.
(2) If founded upon the emended definition by Lonsdale in Mur-
chison's Silurian system, the type would necessarily be the G.
disticha Lonsdale, which is a Wenlock fossil and probably
quite different from the Devonian G. disticha of Goldfuss. An
examination of a number of specimens of Lousdale's species,
which we owe to the kindness of Mr, Vine, has convinced us
that the Wenlock species is totally different from those for which
Pinnatopora is proposed. In fact they cannot belong to the
same family, Lonsdale's G. disticha being closely related to
Nematopora Ulr., and probably constitutes an extreme member
of the Arthrostylidte. Billings' Helopora strigosa is a con-
generic species.

The AMPLEXOPORID.E is the same as in this volume, save that
Monotrypella. a genus very closely related to Amplexopora, is
out being placed with the MONTICULIPORID.E under the ZOANTHA-
RIA.

* Much evidence was published in Part I of our memoir on "American Palaeozoic
Bryozoa," (Jour. Gin. Soc. Nat. Hist. Vols. V, VI and VII), to establish the bryozoan
nature of the Monticuliporoids. More still, and, among the latter probably some of the
most important, was reserved to be drawn upon in case our views were criticised. But
no call being made upon it, and the reserve being reinforced continually by new evi-
dence gathered during the progress of our studies, we are now enabled to claim with
confidence, that when the subject is again taken up by us, we will support our views
with such an abundance of evidence that even the most skeptical of our opponents,
provided he is just, must be convinced of their truth. The matter for the paper on the
"Relations of Palaeozoic to Mesozoic, Tertiary and Recent Bryozoa," has been ready
for several years, and only awaits an opportunity when it may be published, properly
supported by illustrations.

-85

682 PALAEONTOLOGY OF ILLINOIS.

The ARTHROSTYLHLE and ASCODICTYONID.E also are constituted
as in our classification, but under the BATOSTOMELLIDJE we miss
Bythopora, Callotrypa and Stenopora, the last being placed
among the corals, and the second among the TREMATOPORHLE,
while a new family, the BYTHOPORID^E, is proposed for the firwt.
The family as given by him embraces besides Anisotrypa, Ba-
tostomella and Leioclema, also Batostoma (?) and Peronopora,
the latter probably through a clerical error, since on p. 199, he
places the genus as a synonym for Monticulipora*

The BOTRYLLOPORHLE, including only Botryllopora, may be a
good family. We did not feel warranted in proposing a new
family and in our classification have doubtfully referred the
genus to the FISTULIPORHLE.

The CERAMOPORID^, however, is a heterogeneous assemblage.
Thus, beside Ceramopora, Ceramoporella, Chiloporella, Crepipora
and Spatiopora, which are properly referred here, the family is
made to embrace Eridopora, Glossotrypa, Lichenalia, Licheno-
trypa, Odontotrypa, Pileotrypa and Selenopora, all genera
that, if not actual synonyms for Fistulipora, are at any rate
so closely related to that genus that they must belong to the
same family. None of them possess the structure characterizing
the Ceramoporoids, while all have the vesicular interstitial
tissue and zocecial wall structure marking the Fistuliporoids.

Ceramella, an unquestionable synonym for Glyptopora and
therefore a genus related to Cystodictya, (referred by Mr. Miller
to the STICTOPORHLE) is also placed here, together with Peti-
gopora, a genus whose minute structure agrees intimately with
Dekayia, which, as we have seen, he puts with the ALCYONARIA.
Sagenella, founded upon a species, that if it is not strictly a
Berenicea, clearly belongs to the TUBULIPORID^E and Phracto-
pora, the relations of which are uncertain and which he also
refers to the STICTOPORID.E, complete the list of genera placed by
him as CERAMOPORID.E.

* It is interesting to note how differently authors view the Monticuliporoid divisions
proposed by Nicholson. Contrast with the above Waagen and Wentzel's recent erection
of the subfamily Peronoporince (Pal. Indica, Ser. XIII, I, 6.)

BRYOZOA. 683

The erection of a new family for Crisinella may be justifiable
in a work of that kind ; but not so the ENALLOPORID.E, under
which he ranges Diploclema, Enallopora and Protocrisina, since
the EXTALOPHORID.E will include these genera without any ex-
tension of its usually accredited limits. We must protest also
against the use of d'Orbigny's Enallopora instead of our Mito-
clema. Ennllopora was founded upon Hall's figures and des-
cription of Gorgonia (?) perantiqua (Pal. X. Y. Vol. I, 1847.) Mr.
Miller gives the following free translation of d'Orbigny's des-
cription (Prodr: d. Pal. T. 1, p. 22, 1850.) "Small bifurcating
branches, without connecting bars; cell-mouths prominent on
each side, opening laterally and alternately." How can this
description be made to include Mitoclema cinetosum, in which
cylindrical stems are encircled by transverse rows of zooecial
apertures as in Spiropora and Enthalophora! Nor are we
acquainted with any bryozoan from the Trenton rocks having
two rows of alternately arranged and outwardly projecting cell-
apertures. The species which we originally identified with Hall's
G. (?) perantiqua (Jour. Cin. Soc. Xat. Hist. Vol. V, p. 159,)
since it was found to agTee neither with the description nor
with the figures given by Hall of that species, is now described
as new and made the type of the new genus Diploclema, a sub-
sequent and more careful examination having developed that
we were wrong in uniting the species with Mitoclema* We
have also become convinced that Hall's work on his Gorgonia
(?) perantiqua is faulty and that Enallopora rests upon char-
acters that are hypothetical and with no existence in nature.
If this view is right, then Enallopora cannot stand, since it
fails to fulfill the first and most important rule of nomenclature
in this that the description is not sufficient for the identification
of the organism named. And there is no rule known to us per-
mitting the retention of a genus founded upon imaginary char-
acters.

His FEXESTELLID.E embraces all the genera placed there by us
save Thamniscus. D'Orbigny's very doubtful Reteporina, and

* For further remarks upon this subject see note under Protocrisina eiigua (p. 405}
which is another of the forms that have been identified with Hall's species.

084 PALEONTOLOGY OF ILLINOIS.

Clathropora, Goscinella, Coscinium, Coscinotrypa, Evactinopora,
Reptaria and Semiopora are also included.

Upon what grounds the last seven genera are placed into the
same family with Fenestella, etc., is beyond our comprehension;
and we are thoroughly satisfied that no one who has paid even
the most cursory attention to fossil Bryozoa, will follow him.
Clathropora differs from Ptilodictya only in its mode of growth,
and Coscinella and Coscinium are distinguished from Intrapora
and Cystodictya in precisely the same manner. In their inter-
nal and really essential structure each pair of these genera is
practically identical. Co&cinotrypa Hall, is a pure synonym for
Coscinium* while Semiopora, as defined and figured by Hall,
(Pal. N. Y. Vol. 6, 1887,) is indistinguishable from Phssnopora.

Evactinopora also, though regarded by us as a very good
generic group, is distinguished from Glyptopora and the other
genera comprised in our CYSTODICTYONID.E, almost solely by char-
acters resulting from its peculiar style of growth. The zooecial
features are essentially the same in all, constituting the CYSTO-
DICTYONID^E one of the most natural and easily recognized fami-
lies of Palaeozoic Bryozoa. We were, therefore, not a little dis-
appointment at finding that the family was not adopted by
Mr. Miller. In splitting up the family and re-distributing the
genera he has been very unfortunate, especially in placing one
among the CERAMOPORID.E and several with the FENESTELLHLE.
The remainder he puts with the STICTOPORIDJE which is a less
unreasonable allocation.

Rcptaria also, surely has nothing in common with the Fenes-
tellidas, and, if it is a bryozoan at all, must go with Hederella
into the Cyclostomata near the Tubuliporidse.

*It should be remarked here that Mr. Miller regards Glyptopora Ulr., (erroneously
written Glyptotrypa by him) as not distinct from Coscinium Keyserling, and that he
has apparently overlooked the new species of Glyptopora described in this volume.
He gives no reasons for thus ignoring our genus, and it is a little surprising to find
that he has not emended the definition of Coscinium so as to cover Glyptopora, but
leaves it so that its terms include only the cribriform species for which Keyserling
proposed the genus and for which the name was adopted by Hall, Ulrich and others.
On the other hand he accepts Hall's Coscinotrypafor Coscinium cribri-forme wh ch we,
in accordance with the anthor of the species, regard as one of the most typical species
of Keyserling's genus. Such a proceeding does not appear just to us. We may add
further that the characters which he assigns to Coscinotrypa ought to be joined to his
description of 'Coscinium to make it complete.

BRYOZOA. 685

The FISTULIPORID.E as recognized by him contains besides those
genera that we place there, also Actinotrypa, Callopora, Callo-
porella and Callotrypa. In his definition of the first of these
genera (p. 291,) the only feature mentioned as distinguishing-
it from Dichotrypa, which he places among the STICTOPORID.E,
are the radial striae that extend down the vestibular portion of
the zooecial aperture in Actinotrypa. And yet the two genera
are placed into different families. It is now a well established
fact that Callopora is without the interstitial vesicles which char-
acterize the FISTULIPORID.E, and, therefore, ought not to belong
to the same family. The same is true of Callopoi-ella and Callo-
trypa, but the latter has the structure of the BATOSTOMELLIDJE,
its systematic position being intermediate between Bythopora
and Leioclema. He also places in this family (the FISTULIPORHXE)
Eridopora, Lichenotrypa and Selenopora, a reference that we
believe correct, at any rate more so than under the CERAMO-
PORID.E, where they also occur.

The HELIOTRYPID.E includes, as in our work, only the genus
Heliotrypa. But why is this genus also placed with the STICTO-
PORID.E as we will see presently?

The next family is the LABECHIID.E, with one genus, Labechia
Ed. & H. Mr. Miller himself seems to have doubted that this
genus belongs to the Bryozoa, since on p. 310, he supplements
his definition with this remark: "Probably this genus belongs
to the Protozoa and is related to the Sponges." We were not
aware that anyone doubted that Labechia is an unequivocal Stro-
matoporoid, and consequently far removed from the Bryozoa.

The PALESCHARID.E and PHACELOPORID.E include as with us each
only its typical genus.

Under the PTILODICTYONID.E, however, he has struck out Clath-
ropora, Arthropora, Intrapora, Semiopora Stictoporella and
Tseniodictya, all of which, except the first and fourth, that, as
has been stated alreadj7, he refers to the FENESTELLID.E, he places
with the STICTOPORID.E, a course that is unwarranted if we credit
zooecial features with importance in the framing of our classifi-
cations. Furthermore, our family STREBLOTRYPIDJ-: is set aside

686 PALEONTOLOGY OF ILLINOIS.

and the five genera Cyclopora, Cycloporella, Proutella, Streblo-
trypa and Worthenopora, which, with us constitute that divi-
sion, are removed to this family, a proceeding for which there
is even less reason than in the preceding case. In fact the
STREBLOTRYPID.E is one of the best marked families of Palaeozoic
Bryozoa, resembling the PTILODICTYONIDJE much less than do
the STICTOPORID.E and some of his FENESTELLID.E. A union with
the RHABDOMESONTID.E might have been comprehended and per-
haps excused by us, since that family embraces some of its
nearest relatives. Coscinella, we believe, is properly placed in
the family, but he has also put the genus with the FENESTELLID.E,
while Intrapora, to which Coscinella is very nearly related, is
found among the STICTOPORID^E.

The RHABDOMESONTHLE is constituted as in this volume, only
Anisotrypa belongs with the BATOSTOMELLHLE, where he has
also placed it.

The RHINOPORID.E and SPHRAGIOPORID.E embrace as in this
work only the typical genera.

STICTOPORID^:. — In this family he places, besides the genera that
we refer there, also Acrogenia, Cystodictya, 'Dichotrypa, Phrac-
topora, Prismopora, Scalaripora and T&niopora which with us
form the bulk of our CYSTODICTYONID^} ; also Arthropora, Intra-
pora, Stictoporella and Tseniodictya, which we refer to the
PTILODICTYONID^E on zooecial characters mainly; and Heliotrypa
which, a little higher on the page, he makes the type and only
genus of the HELIOTRYPIDJS.

His family SUBRETIPORID^E is in every way equivalent to our
PHYLLOPORINID.E, he being of the opinion that Phylloporina Ulr.,
is the same os Subretepora of d'Orbigny.

This is a case very nearly like that between Mitoclema and
Enallopora, discussed above. D'Orbigny proposed Subretepora
for Hall's Intricaria reticulata, relying upon Hall's description
and figures (Pal. N. Y., Vol. I) for the characters of his genus,
which he defines as having a single row of large cells, occupy-
ing the entire width of the slender, irregularly anastomosing
branches, all of which agrees very well with the data upon

BRYOZOA. 687

which he relied. Now, however, since it is known that Hall's
diagnosis and figures are incorrect in precisely those features
upon which d'Orbigny founded the genus, it is evident that Sub-
retepora must drop out of sight once more, on the ground of
insufficient and incorrect definition. According to our view, it
is neither safe nor proper to found genera upon someone else's
figures or descriptions, particularly if these were drawn or writ-
ten in the '40s, when palaeontological work was not done nearly
so accurate as is now demanded. Nor can we regard it as good
policy to resurrect old and obscure names, especially when they,
like those under consideration, have never been current in palae-
ontological literature. Indeed, so far as we are informed, none
of the genera of Bryozoa proposed by d'Orbigny for species
described by Hall in Vol. I. of the New York Reports on Palae-
ontology, have been used by subsequent writers. They do not
even appear in catalogues like Bigsby's "Thesaurus Siluricus."
Enallopora. Subretepora, and Sukopora (founded upon Hall's
Stictopora fenestrata, which, for the present we regard as the
type of Stictopora), were known to us since March, 1880, but
we placed them, in accordance with what seemed to be common
consent, among the "not recognized" names.

The THAMXISCID.E, including Crisinella, Diplopora, and Tham-
niscus. is not a natural assemblage. Xor does Mr. Miller ap-
pear to have had much faith in the group, since Diplopora oc-
curs among the genera of his ACANTHOCLADHD.E, and Crisinella
is the type of his CRISINELLHXE. Tbanmiscus, the only genus re-
maining is, as we have shown on pages 357 and 606 of this
volume, too clearly related to Polypora to permit of greater
than generic separation.

The TKEMATOPORID.E includes a very peculiar and unnatural
assemblage of genera, showing in a striking manner the incon-
sequence of those authors who deny that Monticulipora, Mono-
trypa. Stenopora, etc.. are Bryozoa. Thus, Mr. Miller places
here besides Acantboclema, Bactropora, Xemataxis and Tropi-
dopora, which he has arranged much more properly also with
the RHABDOMESONTID.E; and Amplexopora and Atactopora which
the reader will find also under the AMPLEXOPORID.E; and Cbilo-
trrpa'which has been already correctly placed with the FISTULI-

688 PALEONTOLOGY OF ILLINOIS.

POKID.*:; Atactoporella, Homotrypa and Homotryj^lla, three
genera closely related to Monticulipora and quite distinct from
Trematopom; Diamesopora, a Ceramoporoid and totally differ-
ent from Trematopora, as founded upon T. tuberculosa; and
Nicholsonella, which of all the genera placed here by Mr. Miller
alone belongs to the same family as Trematapora, Orthopora
being a pure synonym for Rhombopora, and Trematella, most
likely, the same as Batostomella.

The TUBULIPORID^; we find no fault with save in this, that
Sagenella, which he has with the CERAMOPORID.E, ought to go
here, because, if indeed it is not a straight synonym for Bere-
nicea, they are at any rate very nearly related.

INDEX TO VOLUME VIII. 689

INDEX TO VOLUME VIII, PART I.

(Species marked t are figured in the text.)

PAGE

Alluvial deposit - 7

Ammonites in the drift t 4

Analysis of Coal from Kinmundv 42,691

Ananehytes in the drif rt 4

Ancient channels and valleys 11,14,28,33,36,39

Ancient soils in the drift 9,14,15,16,18

Artesian water in Illinois 64

Artesian wells in Northern Illinois 63

Artesian wells in Southern Illinois 63

Artesian well at Beardstown 65

Canton 62

Carthage 62,64,65

Hamilton 65, 65

Jacksonville 66

Monnaouth 62,66,691

Olney 63

B AxyisiEB, DB., report on drift 12

Belemnites in the driftt 4

Bos primigenius 8

Boulder clays 9,17

BBADLEY, FBAXK H.. on ancient channel a western outlet of Lake Michigan 11,28,34

BBTCE, GEO. C., record of boring at Hillsboro 46

Castoroides ohioensis 8

Coal, analysis of 42

Coal in Illinois 25

Southern Illinois 54

COLE, C. B., records of borings 58

Co UN-TIES:

Adams Co., Loess at Quincy 8

Carroll Co. drift 10

Champaign Co. drift 12,28

GaUatin Co. coal 54

Hancock Co. , section of bluffs at Warsaw 7

Iroquois Co. drift 11

Jackson Co. coal :,;

Jefferson Co., Coal at Mt. Yernon 56

Kankakee Co. drift 11

Lee Co. drift 11

Livingston Co. drift 12

M'-Lean Co. drift 12

Menard Co. loes 7 8

Ogle Co. drift 10

Whiteside Co. drift 11

—86

690 INDEX TO VOLUME VIII.

PAGE.

COUNTIES— Continued.

Section of Strata at Coatsburg, Adams Co 15

Greenville, Bond Co 38

Smithboro, Bond Co 37

Sorento, Bond Co 39,40

Mt. Carroll, Carroll Co 10

" " Beardstown, Cass Co 61

Virginia, Cass Co 16

Champaign, Champaign Co 27

Sidney, Champaign Co 17,27

Palmer, Christian Co 16

Pana, Christian Co 15

Mattoon. Coles Co 36

Clinton, DeWitt Co 13,34,35,58

Tuscola, Douglas Co 17,26

" Efflngham, Effingham Co 55

Canton, Fulton Co 62

Carthage, Hancock Co 65

Hamilton, Hancock Co 68

Warsaw, Hancock Co 7

Elkville, Jackson Co 52

" " New Burnside, Johnson Co 54

near Lake Forest, Lake Co 12

Cullom, Livingston Co 29

" Odell, Livingston Co 14

Saunemin, Livingston Co 31

Strawn, Livingston Co 28,30

Pulaski, Logan Co 50

Decatur, Macon Co 15,48,691

Medora, Macoupin Co 51

Kinmundy, Marion Co 41.44

Odin.Marion Co 43,44

Salem, Marion Co 44

Sandoval, Marion Co IS

Wenona, Marshall Co 13

• " Bloomington, McLean Co 14

Menard Co 16

Waverly, Morgan Co 50

" " Jacksonville, Morgan Co 66

' ' Franklin, Morgan Co .- 50

' ' Hillsboro, Montgomery Co 46,691

Galum Creek, Perry Co 56

Harrisburg, Saline Co 54

Sangamon Co 16

Lementon, St. Glair Co 18

Monmouth, Warren Co 66

of drift in Southern Illinois 18

Cretaceous fossils in the drift of Illinois 3

Cretaceous strata in Iowa, former extent of 6

CUMMINS, T. 8., letter on coal in Livingston Co 32

Devonian strata in Illinois 63,64

Drift.ancient soils in 9,14,15,16,18

' ' cretaceous fossils in 3

' ' deposits in Illinois 1

' ' mammalian remains in 8

' ' modified 7

INDEX TO VOLUME VIII. 691

PAGE.

Drift, subdivisions of 7,9

theories of formation 19

' ' period, commencement of 2

Erosion in Illinois 3, 4

Gas, natural, in Illinois 13,58

Gas, natural, in Ohio and Pennsylvania 61

Glacial theory discussed 19

Helicina occulta in the drift 15

Lake Michigan, ancient western outlet of 11,14,28

Lamna, in the drift + 4

Loess 7.9

Mammalian remains in the drift 8,23

Mammoth 8

Mastodon 8

Megalonyx 8

Modified drift 7

Native copper in the drift 19

Natural gas and oil in Illinois 58

Oil, natural, in Illinois 58

Oxyrhina crassa in the drift t 4

Ptychodus polygyrus in the drift t 4

River terraces 7

RUTLEDGE, W., reports of borings 36,39,55

SHAW, JAMES, report on northern counties 10

Terrace epoch 7

Tertiary age in Illinois 3

WHITE. Dr. C. A. former extent of cretaceous strata in Iowa 6

ERRATA IN PART I.

Page 42, line 3 from bottom, for 100.04 read 100.14,
Page 49, line 11 from bottom, for 528-6 read 628-6.
Page 62, line 19 from top, for 1,088 read 1,078.

The Hillsboro boring log, on pages 46 and 47, bearing various evidences of incor-
rectness, I wrote to Mr. GEO. C. BBTCE, who kindly furnished me the following cor-
rections:

Ft. In.

11 Limestone (Shoal Creek) 8

15 Sandy shale and sandston • 63 4

22 Limestone 6

25 Clay shale 1 10

27 Bituminous shale 6

35 Coal, 1 ft; slate, 6 in.; coal, 1 ft. 6 in.— No. 5 3 ..

Total depth 775 feet.

(J. L.)

INDEX TO VOLUME VIII. 693

INDEX TO VOL. VIII, PAKT II.

SECTIONS 1 AND 2.

(Numbers in Full Face refer to diagnosis. An asterisk (*) after the number of the page
indicates that the species is figured.)

PAGE.

Actinocrinidae 163

Actinocrinus Miller 97.163

arnoldi W. & Sp 168*

( ' ' chloris Hall) 163

daphne Hall 163

( " ) helice Hall 176

lobatus Hall 97*

( " ) nashvillae Troost 85

nodobrachiatus W. & Sp 165*

ornatissimus W. & Sp 163*,165,167

proboscidalis Hall 165

tenuisculptus Me. Ch 163

Agaricocrinus Troost 94,96

americanus Boemer 94

mac-adamsi Worthen 94*

nodulosus Worthen 94*

Allocrinus W. & Sp 206

typus W. & Sp 207*,699

AHorisma King 132

elongata Worthen 133

illinoiensis Worthen 132*

' ' marionensis White 132

subcuneata Meek and Hayden 133

Amphoracrinus Austin 96

jerseyensis Worthen 96*

Amplexus Sowerby 82

geniculatus Worthen 82*

Anisophyllum Edwards and Haime 80

iovense Worthen 80*

Antedon larva 161

Articulata (suborder of Crinoidea) 197

Ascoceras Barrande 151

southwelli Worthen 151*

Athyris McCoy 103

' ' squamosa Worthen 103*

694 INDEX TO VOLUME VIII.

PAGE.

Aviculopecten McCoy 112

chesterensis Worthen 115*

colletti Worthen 119*

edwardsi Worthen 119*

elsahensis Worthen 115*

hardinensis Worthen 117*

mac-whortheri Worthen 118*

' ' • mazonensis Worthen 117*

menardi Worthen 120*

monroensis Worthen 114*

niotensis" Worthen 113*

orestes Worthen 112*

providensis Cox (PI. XXI, figs. 4, 4a) 116*

spinulif erus Meek and Worthen 116*

talboti Worthen 114*

varsoviensis Worthen 113

Aviculopinna Meek 128

" illinoiensiS Wortheu 128*

Bakevellia King 126

' ' illinoiensis Worthen 126*

Barycrinus Wachsnmth 99

spurius Hall 99*

tumidus Hall 100*

Batocrinus Casseday 83,172, 173,174

biturbinatus (Hall) 84

mac-bridei W. & Sp 172M74

montgomeryensis Worthen 83*

' ' nashvillae Troost 85*

subconicus Worthen 84*

' ' unionensis Worthen 84*

Bellerophon Montf ort 143

' ' giganteus Wurthen 143*

Blastoidea 201

Brachiopoda 102

Calceoerinus Hall 92

robustus Worthen 92*

tunicatus Hall 93*

Camerata 163

Cardiomorpha DeKuninok 126

(?) pellensis Worthen 126*

Centrocrinus Wachsmuth and Springer 95

tennesseensis Worthen 95*

Cephalopoda 148

Chaetetes Fischer 169

(Cheirocrinus) tunicatus Hall 93

Clinopistha Worthen 122

radiata Hall 122*

Codasteridae 201

Codonites gracilis M. & W 201

( " stelliformis M. & W.) 201

Coalocrinus concavus M. & W 177

Colpocaris Meek 153

chesterensis Wortheu 153*

Conocardium Bronn 112

parrishi Worthen. .. 112*

INDEX TO VOLUME VIII. 695

Conularia Miller

chesterensis Worthen

Crinoids and Blastoids

Crinoidea ".."...."...,."..

Crustacea

(Cyathocrinus tumidus Hall)

( ) bullatus Hall "...J...J......

Dentalium Linna?us

illinoiense Worthen 14g*

Dichocrinus Austin

inornatus W. & Spr j'^' '^ '19Q*

ornatus Owen an ' Shumard
simplex Shum .

190
190

SP, ondeecribed

102*

Discina Lamarck 102

varsoviensis Worthen...

Dolabra orbicularis McCoy .....................................

Dorycrinus Roemer ............................................. irw> i~s

concavus Meek and Worthen ............................ j«~

helice (Hall)...

..................................... 17b

immaturus W. & Sp... ...................................... 174,175*,176

mississippiensis Eoem ....................................

parvibasis W. & Sp ......................................... 177

radiatus W. & Sp ................................... ,-6

Edmondia DeKoninck ..................................

illinoiensis Worthen ......................................... J22*

varsoviensis Worthen ............................... joi*

Eretmocrinus Lyon and Cass. . . ,-•? i- .

.............................. Ltof 1/4

Eupachycrinus Meek and Worthen ......................................... 97

orbicularis (Hall) ...................................... g^»

(?) sancti-ludovici Worthen .............. oo

Fistulata ...................................................... ......... " 19g

Gasteropoda ................................................ .....

Goniatites DeHaan ...........................................

monroensis Worthen ....................................... i eg*

Graphiocrinus DeKoninck and LeHon ............................ 193

longicit rifer W. & Sp ....................... ..................... jgg*

spinobrachiatus (Hall) ...................................... 193

wachsmuthi (M. & W.) ..................................... 193

Icthyocrinida? ......................................................... 19_

Inadunata ..................................................... ,„„

Kinderhook epoch at LeGrand. Iowa ................................ 15g

Lamellibranchiata ......................................................... 107

LeGrand fossils...

140

Lepetopsis Whitfleld

chesterensis Worthen

Leptodomus McCoy

(?) magnus Worthen JQ^*

Lima Bruguiere ,.>.>

chesterensis Worthen 120*

Linsnila Bruguiere 1(I4

mytiloides Sowerby 1ft-

varsoviensis Worthen.

Lophophyllum E. & H

104*

696 INDEX TO VOLUME VIII.

PAGE.

Lophophyllum profundum Worthen 79*

Loxonema Phillips 139

eerithiiforme Meek and Worthen 139

' ' peoriense Worthen 139*

Quadri-carinatum Worthen 140*

Macrocheilus Phillips 143

altonense Worthen 143*

Macrodon Lycett 123

sangamonensis Worthen 123*

Marshall county, Iowa, strata and fossils 157

Megistrocrinus Owen and Shumard 169

nobilis W. & Sp 169*

parvus W. & Sp 171*

Modiola Lamarck ' 125

' ' illinoiensis Worthen 125*

Murchisonia D'Arch. & Vern 141

• ' keokuk Worthen 141*

* ' lasallensis Worthen 141*

Myalina DeKoninck 127

" monroensis Worthen 127*

Naticopsis McCoy 144

' ' madisonensis Worthen 144*

Nautilus Breynius 148

montgomeryensis Worthen 148*

Nucula Lamarck 128

illinoiensis Worthen 128*

Onychocrmus W. & Spr 199

Oolitic limestone at LeGrand, Iowa 157

Orophocrinus von Seebach 201

conicus W. & Sp 201*,204

fusiformis W. & Sp 201,203*

stelliformis (Owen and Shum.) 201

Orthis Dalman 106

• ' resupinata Martin 106

resupinoides Cox 106*

Oi thonema Meek and Worthen 145

' ' carbonarium Worthen 145*

Orthoceras Breynius 148

illinoiense Worthen 148*

lasallense Worthen 149*

okavense Worthen 149*

rushense McChesney 149

sp 151

Palseocrinoidea Wachsmuth and Springer , 83

Pelmatozoa 163,201

Pentacrinus Schlth 161

(Pentremites) stelliformis Ow. & Shum . . 201

Pinna Linnteus Ill

Pinna missouriensis Swallow Ill

sancti-ludovici Worthen Ill*

Platycrinidfe 186

Platycrinus Miller 186

Platycrinus burlingtonensis O. & Sh 186

" halli Shumard ..189

INDEX TO VOLUME VIII. 697

PAGE.

Platycrinus pileiformis Hall 186

planus Owen and Shumard (?) 188*

pratteni Worthen 189

symmetricus W. & Sp ...186*

truncatulus Hall 188

Pleurophorus King 12}

chesterensis Worthen 123*

minimus Worthen 124*

monroensis Worthen 125*

Pleurotoniaria Defrance 135

adamsi Worthen 137*

( cozana Worthen) 138

giffordi Worthen 135*

illinoiensis Worthen 135*

iovensis Worthen 138*

montezuma Worthen 136*

nauvooensis Worthen 137*

subconstricta Meek and Worthen 136

Polyphemopsis Portlock 144

(?) keokuk Worthen 144*

Porcelh'a LeYeille 138

peoriensis Worthen 138*

Poteriocrinida? 193

Poteriocrinus Miller 86

buffaloensis Worthen ." 89*

elsahensis Worthen 88*

mamma?f ormis Worthen 91*

nodobasalis Worthen 89*

rowleyi Worthen 90*

spinuliferus Worthen 86*,90

ulriehi Worthen 87*

Pteropoda 134

Rhodocrinidas 180

Rhodocrinus kirbyi W. & Sp 172,180*

namis M. & W 182*

watersianus W. & Sp 184*

Rhynohonella Fischer 104

illinoiensis Worthen 104*

ottumwa White 132

wilsoni Sowerby 104

Sangu'nolites McCoy 129

(?) burlingtonensis Worthen 129*

(?) multistriatus Worthen 129*

randolphensis Worthen 130*

Scaphioerinus Hall (emend. W. & Sp.) 195

elegantulus W. \- >r 195*

globo?us W. \- Sp 196*

nanusM. X- W 195

) orbicularis Hall 97

( * ' ) spinobraehiatus Hall 193

sp., undescribed 162

( " ) wachsmuthi M. & W 193

Schizodus King 107

chesterensis Worthen 108

-87

698 INDEX TO VOLUME VIII.

PAGE.

Schizodus (?) circulus Worthen 109*

depressus Worthen 109*

( ' ' magnus Worthen) 107

' ' nauvooensis Worthen 108*

randolphensis Worthen 110*

ulrichi Worthen 110*

varsoviensis Worthen 107*

wheeleri Swallow 110

Solenocaris Meek 153

sancti-ludovici Worthen 153*

Solenocheilus Meek and Worthen 150

collectum Meek and Worthen 151

indianense Worthen 150*

Solenomya Lamarck 131

(?) iovensis Worthen 132*

' ' monroensis Worthen 131*

varsoviensis Worthen 131*

Spirifera Sowerby .' 105

' ' multigranosa Worthen 105*

littoni Swallow 132

SPBINGEB, FBANK (see Wachsmuth and Springer.)

Straparollus Montfort 142

subumbilicatus Worthen 142*

umbilicatus Meek and Worthen 142

varsoviensis Worthen 142*

Taxocrinus Phillips '. 197

fletcheri Worthen 197*

intermedius W. & Sp 199*

Temnocheilus McCoy : 151

coxanum Meek and Worthen 151

scottense Worthen ....: 151

Terebratula Llwyd. 102

rowleyi Worthen 102*

Trachydomia Meek and Worthen 146

nodulosa Worthen 146*

Traehypora Edwards and Haime 81

austini Worthen 81*

ornata Rom 81

WACHSMUTH and SPBINGER, Crinoids and Blastokls 157

WACHSMUTH and SPKINGEK, New Genus of Crinoids from W. Tennessee 206

Waverly beds ol Ohio 160

WHITE, C. A., on the Burlington bed* 159

WOBTHEN, A. H., Fossil Invertebrates 69

Zaphrentis Eaflnesque 71, 132

calcariformis Hall 74*

carinata Worthen .- 75*

centralis E. & H 72*

chesterensis Worthen 73*

cliffordana E. & H 75*

cylindracea Worthen 78*

dalei E. & H 71*

illinoiensis Worthen 77*

lanceolata Worthen. . . 76*

INDEX TO VOLUME VIII. 699

PAGE.

Zaphrentis parasitica Worthen 79*

pellensis "Worthen 74*

reversa Worthen 78*

spergenensis Worthen 77*

( ' ' spinulifera Hall) 71

spinulosa E. & H 73*

ulrichi Worthen 76*

varsoviensis Worthen 78*

Zeacrinus Troost (Hall) 91

Zoantharia . 71

ERRATA IN PART II, SECTIONS 1 AND 2.

On Page 74, change Z. PELLAENSIS to Z. PELLENSIS.
On Page 75, change Z. CARINATUS to Z. CARINATA.
On Page 76, change Z. LANCEOLATUS to Z. LANCEOLATA.
On Page 78, change Z. CYLINDRACEUS to Z. CYLINDRACEA.

On Page so, change Z. cylindraceus to Z. cyliudracea.

On Page 80, change A. IOVAENSIS to A. IOVENSE.

On Page 110, after A. providensis, Cox, sp. insert (PI. XXI, figs.

4, 4a.)

On Page 136, change PL XXIV, Fig. 2 to PL XXIV, Fig. 5.

On Page 138, change PEUROTOMARIA IOWENSIS to PLEUROTOMARIA

On Page 143, change M. ALTONEXSIS to M. ALTONENSE.

On Page 207, line 4 from bottom, leave out the word large before plates.

On Page 207, Line 3 from bottom, change smaller to larger.

INDEX TO VOLUME VIII. 701

INDEX TO VOL. VIII, PART II.

SECTIONS 3, 4 AND 5.

(Numbers in Full Face refer to pages where diagnosis or description is given. An
asterisk(*) after a number indicates that the species is figured.)

PAGE.

Acanthoconia Hinde 238

Actinostroma Nicholson. 221,282

? trentonense Ulrich and Everett 282*

Amblysiphonella Steinman 218

American Palaeozoic Sponges 211,233,245,255

Anomocladina Zittel 225,226,234

Anthaspidella Ulrich and Everett 217,222,234,257

fenestrata Ulrich and Everett 234,264*

firma Ulrich and Everett. 234,263*

florifera Ulrich and Everett ^34,257, 259*

grandis Ulrich and Everett 234,262*

? magniflca Ulrich and Everett 235,265*

mammulata Ulrich and Everett 233,257, 258*

obliqua Ulrich and Everett 235, 265*

parvistellata Ulrich and Everett 235,260*

scutula Ulrich and Everett 235,261*

Anthaspidellidae Ulrich 221, 234

Archaeocyathus Billings 216,240

atlanticus Billings 240

billingsi Walcott 240

? pavonoides Matthew 240

Astraeospongia Roemer 217,238

hamiltonensis Meek and Worthen 238

meniscus Roemer 238

Astroconia Sollas 238

granti Sollas 238

Astylospongia Roemer 217,223,234

Christiana Meek and Worthen 234

imbricato-articulata Roemer 234

inciso-lobata Roemer 234

inornata Hall 227

? parvula Billings 234

? perryi Billings 234

pi aemorsa Goldfuss 224*,234

prsemorsa var. nux-moschata Hall 234

roemeri Hinde . . 234

702 INDEX TO VOLUME VIII.

PAGE.

Astylospongia stellatim- sulcata Boemer 234

Aulocopina Billings 240

grant! Billings 240

Aulocopium Oswald 217,222,223,2251

Batospongia Ulrich .' 218,239, 246

spicata Ulrich 238, 246*

Beatricea 216

Becksia 223

Belemnospongia Ulrich 233,248

fascicularis Ulrich 218,233, 248*

Brachiospongia Marsh 217,238

digitata Owen, sp 238

Brachiospongidae Beecher 217, 238

Buthotrephis 255,280

(Calamopora Goldf) '. 227

( ' ' flbrosa Goldlusa) 228

Calathium Billings 210,235,250,275

afflne Billings 235

anstedi Billings 235

? canadense Billings 235,250,275

flttoni Billings 235

f ormosum Billings 235

?? infelix Ulrich and Everett 235,250,274*

pannosum Billings 235

paradoxicum Billings 235

Calcispongise Blainville 220, 239

Camarocladia Ulrich and Everett 217, 23<», 280

dichotoma Ulrich and Eveiett 231), 281*

Cambrian System, Sponges of 216,233

Carboniferous System, Sponges of 218,233,245

Ceraospongiae Bronn .' 220

Classification of Sponges 219,233

Cleodictya Hall 236

gloriosa Hall 236

^mohriHall 236

Climacospongia Hinde 217,222,223*,235,248,268

(radialis Hinde— in error for C. radiata) 235

radiata Hinde 224t,235,248

Cnemidiastrum 221

(Cnemidium?) treutonense Worthen 270

Coal Measures, Sponges of 233

Corynella 215

Craticularia Zitiel 222

Cyathophycus Walcott 216,217,236,280

quebecense Dawson 236

reticulatum Walcott 236

subsphericum Walcott 236

Cyathospongia Hall 234

excrescens Hall 234

Cylindrocoelia Ulrich 217,240

endoceroidea Ulrich 240

covingtonensis Ulricii 240

minnesotensis Ulrich 240

' ' minor Ulrich 240

INDEX TO VOLUME VIII. 703

PAGE.

Devonian System, Sponges of 218,233,215

Dictyophyton Hal) 216.218,236

abacus Hall 236

annulatum Hall 236

baeulum Hall 236

cinctum HalL 23C

conradi HalL 235

cylindrieum "WhitfieM 236

fenestratum Hall 236

filitextile Hal! 236

hamiltonense Hall 236

irregulare Hall ^36

nodosum Hall .f 236

parallelum Hall 236

patulum Hall 236

prismaticum Hall 236

? redfieldi Hall 236

rude Hall 237

sacculus Hall 237

telum HalL 237

tenue HalL 2:~

tuberosum Conrad 237

Dietyospongidae Hall 236

Dystactospongia Miller 215,217.23 1

insolens S. A. Miller 239

minima Ulrich 23.1

minor Ulrich and Everett 239,278*

rudis ririch and Everett 239,279*

Ectenodictya Hall 237

burnngtonensis Hall 237

eccentrica Hall 237

expansa Hall 237

implexa HalL 237

Edriospongia Ulrich and Everett 217,235,271

basalis Ulrich and Everett 23.'. 272*

Eocoryne Matthew 240

' ' gemina Matthew 240

Eospongia Billings 217, 234

rremeri Billings 234

varians Billing? 234

Ethmophyllum Meek .' 216,240

minganense Billings, sp 240

profundum Billings, sp 240

rarum Ford, sp 240

rensselaericum Ford, sp 240

whitneyi Meek 240

Euretidae Zittel 2±2

Fenestella, associated with sponges 2 '5,249

Fossihzation of Sponges 212

Geological Distribution of Sponges 211,215

Heterospongia Ulrich 21 " . C " _

aspera Ulrich 239

knotti Ulrich 236

subramosa Ulrk-h . . 239

704 INDEX TO VOLUME VIII.

PAGE.

Hexactinellida Schmidt 220,236

Hindia Duncan 226,234

inasqualis Ulrich and Everett 234, 275*

( ' ' inornata Hall) 228

parva Ulrich 234

sphasroidalis Duncan 225*,234

Holasterella Carter 218

Hyalostelia Zittel 217,238

delicatula Ulrich 238,246t

metissica Dawson 238

L ' ' solivaga Ulrich 232, 238

Hydnoceras Conrad 216

Hystriospongia Ulrich 218, 233, 245

carbonaria Ulrich 2*3, 245*.246t

Ischadites Murchison 238

Jerieca Zittel 226

Lasiocladia Hinde 218,233

compressa Hinde 233,249

hindei Ulrich 233, 249

Lepidolites Ulrich 217,239

dickhauti Ulrich 239

r ' ' elongatus Ulrich 239

Leptomitus Walcott 216,233

zitteli Walcott 233

Leptopoterion Ulrich 217,239

mammif erum Ulrich 239

List of Lower Trenton fossils, DE. EVERETT, Dixon, 111 256

Lithistida Schmidt 220,234

Lodanella mira Kayser 218

Lyrodictya Hall 237

romingeri Hall 237

Lyssacina Zittel .' 236

(Micro^pongia Miller and Dyer) 226,228,229

( gregaria Miller) 229

MonactineJlidae Zittel 220,233

MonakidaB Marshall 238

Myxospongise Haeckel .' 220

Ophiorhaphidites Carter 245

Pachastrella Schmidt 245

Palaeomanon Eoemer 217,223,234

bursa Hall 234

cratera Eoemer 234

Palaeophycus Hall 255

Pattersonia Miller 217,240

difflcilis S. A. Miller 240

Peronella 280

Pharetrones Zittel 239

Phragmodictya Hall 237

catilliformis Whitfield 237

lineataHall 237

patelliformis Hall 237

Physospongia Hall 237

alternate Hall;. . 237

INDEX TO VOLUME VIII. 705

PAGE.

Physospongia colletti Hall 337

dawsoni (Whitfleld) 237

Pollakidae Marshall 238

Polypora, associated with sponges 245

Preservation of fossil sponges 212

Prismopora, associated with sponges : 245

Protospongia Salter 216,237

fenestrata Salter 237

? minor Matthew 237

? minor var. distans Matthew 237

tetranema Dawson 237

Pulvillus Carter 218

Baphidistia Carter 218

Bauffella Ulrich 217.236

flliosa Ulrich 236

palmipes Ulrich 236

Reoeptaculites DeFrance 217.238

Beceptaculitidae Hinde 238

Beniera Carter 218

Rhabdaria Billings 240

fragilis Billings 240

furcata Billings 240

Ribeiria Sharpe 241

" ? calcifera Billings 241

longiuscula Billings 241

Saccospongia Uh-ich 217,239

dan illensis Uh-ich 239

rudis Uh-ich 1239

Sebargasia Steinman 218

SECTION III. AMERICAN PALEOZOIC SPONGES 209

SECTION IV. DEVONIAN AND CARBONIFEROUS SPONGES 243

SECTION V, LOWER SILURIAN SPONGES 253

Seliscothon mantelli Goldfuss .- 22o*

Silurian System. Sponges of 217,233,255

Soliasia Steinman 218

(Sphaerolites Hinde) 228

( " nicholsoni Hinde) 227,273

Spongiee, tabular list and classification. 233

Spongia incertse sedis 240

Streptosolen Ulrich and Everett 217,235,257.272,273

obconicus Ulrich and Everett 235,274*

Streptospongia Uh-ich 217, 240

labyrinthica Ulrich 240

Strobilospongia Beecher 217

Stromatoporoidea 216,221,282

Strotospongia Uh-ich and Everett 217,2-39, 276

maculosa Ulrich and Everett 239,277*

Sub-carboniferous System, Sponges of 218,233

Syringelasma Uh-ich— read for Syringophyllum 21*. 222.235, 250

wortheni Ulrich— read for Syringophyllum! 235, 250*

(Syringophyllum Ulrich; name pre-occupied— See.Syringelasma.)
( ' ' wortheni Ulrieh— See Syringelasma wortheni.)

—88

706 INDEX TO VOLUME VIII.

PAGE.

Taconic System, Sponges in 216,233

Tethyopsis Zittel 245

TABULAR LIST AND CLASSIFICATION OF AMERICAN PALEOZOIC
SPONGES 233

Tetracladina Zittel 223,225,226,231,234

Tetractinellida Marshall 220,233

Thamnodictya Hall 237

newberryi Hall 237

Trachyum Billings 216, 241

cyathiforme Billings 241

rugosum Billings 241

Trichospongia Billings 216,241

sericea Billings 241

Uphantaenia Vanuxem 216,218,237

chemungensis Vanuxem 237

dawsoni Whitfleld 218

Verticillites DeFrance 280

Zittelella Ulrich and Everett 217.221,222,235,267,275

( " ?) infelix Ulrich and Everett 271*,274

" inosculata Ulrich and Everett 235,271

lobata Ulrich and Everett 235, 270*

trentonensis Worthen, sp 235,270

typicalis Uh-ich and Everett 235,268*

typicalis var. pistilliformis Ulrich and Everett 235, 269*

typicalis var. subrotunda Ulrich and Everett 235, 269*

typicalis var. turbinata Ulrich and Everett 235, 269*

Zoantharia rugosa, affinity to sponges 216

ERRATA AND ADDENDA.
PART II, SECTIONS 3-5.

Page 211, to the list of genera at the bottom of this page, add: Receptaculites
by Defrance; Iscliadites by Murchison; CerionitOS by Meek & Worthen.

Pages 218, 222, 235 and 250. the name SyriDg'Ophylluw, being pre-occupied,

should be changed to Syringelasma.

Page 218, line 18 from bottom, for SollaCJa read Sollasia.
Page 221, in foot note, for Stromap toroidea read Stromatoporoidea.
Page 233, line 2 from bottom, for 1880 read' 1889.

Page 235, line 2 from top, for A. mamillata read A. mammulata.

Page 235, line 10 from bottom, for C. radialis read C. radiata.

Page 257, line 10 from bottom, for the systems read the canal systems.

Page 272, line 17 from top, for U. & R. read U. & E.

Page 273, line 17 and 18 from bottom, exchange former and latter.

INDEX TO VOLUME VIII. 707

INDEX TO VOL. VIII, PAKT II.

SECTION 6.

Numbers in FuL Face, indicate page -where diagnosis or description is given. A cross
(t) indicates that an illustration is given in the text. An asterisk (*) indicates that an
illustration is given on the plates.

PAGE.

Acanthocladia King 398, 627,635

amerieana Swallow 636

anceps Schlotheim 398,635*

fruticosa Ulrich 635*

Acanthocladiidae Zittel (TJlrich) 361,397

Acanthoclema Hall 402,661

alternatum Hall 666

confluens Ulrich 662*

( " ) hamiltonense Hall (Nicholson)... 648

( " ) scutulatum' Hall 648

Acanthopore? 290,300

Acanthopora Young and Young 358,359

Actinotrypa Ulrich 386, 503

peculiar-is (Rominger) 386, 603*

(Actinostoma Young and Young) 358,359

Acrogenia Hall 388

Amplexopora Ulrich 377, 450

afflnis Ulrich 450*

cingulata Ulrich 308t. 309t, 377

pustulosa Ulrich 451*

robusta Ulrieh 318t

septosa Ulrich 451

superba Foord 450

Amplexoporidae Ulrich 342. 376

Anisotrypa Uh-ich 376

elegantula (Ulrieh) 365, 447

flstulosa Ulrich 448*

ramulosa Uh-ich 449*

eolida Uh-ich 365,449*

symmerrica Ulrich 376, J48*

Anolotichia Uh-ich 381, 473

ponderosa Ulrich 3201, 381, 473*

impolita Uh-ich 473

Apertures 291

708 INDEX TO VOLUME VIII.

PAGE.

Archimedes LeSueur (Owen) 353, 396,565

communis Ulrich 568, 573*

compactus Ulrich 568, 572*

distans Ulrich 568, 578*

grandis Ulrich 568, 569*

intermedius Ulrich 568, 574*

invaginatus Ulrich 568, 575*

laxus Hall 568, 580*

meekanus Hall 568. 578*

negligens Ulrich 568, 569*

owenanus Hall 568, 570*

perminimus Ulrich 568, 572*

proutanus Ulrich 568, 576*

( " reversus Hall) 571

swallovanus Hall 568, 574*

sublaxus Ulrich 568, 579*

terebriformis U Irich 568, 575*

wortheni Hall 396,568, 571*

Arthroclema Billings 363, 400,641

angulare Ulrich 641*

billingsi Ulrich 642

pulchellum Billings 400, 641*

Arthronema Eschscholtz 291

( " ) tenue Ulrich 400

Arthropora Ulrich 349, 393

shafferi (Meek) 308t,393

Arthrostylidae 362,400

Arthrostylus Ulrich 363,400

tenuis Ulrich 400

Ascodictyon Nicholson and Etheridge jr 367

fusiforme Nich. and Ether, jr 367

Ascodictyonidae Ulrich 367

Aspidopora Ulrich ; ; 373

areolata Ulrich 373

Atactopora Uh-ich 377

hirsuta Ulrich » 377

Atactoporella Ulrich 370, 412

ortoni Nicholson 418

typicalis Uh-ich 370

Aulopora 454

Avicularia 301

Bactropora Hall 402,662

' ' granistriata Hall 402

simplex Ukich 447, 663*

Batostoma Ulrich 379, 459

fertile Ulrich 459

imperfectum Ulrich 460*

implicatum Nicholson 379, 459

irrasum Uh-ich 460

jamesi Nicholson 459, 460

ottawense Foord * 460,461

' ' variabile Ulrich . . ... 460*

INDEX TO VOLUME VIII. 709

PAGE.

Batostomella Ulrich 375, -132

abrupta Ulrich 435*

gracilis (Nicholson) 375,432,434

intersttncta Uh-ich 434*

nitida (read nitidiila) 365

nitidula Ulrich ,» 365, 436*

obliqua Uh-ich 433*

simulatrix Ulrich 432*

spinulosa Uh-ich 365,375, 434*

(?) trentonensis (Nicholson) 433

Batostomellidae Uh-ich 341,375

Berenicea Lamouroux 368

dihmana Lamx 3Q<

Bidiastopora d'Orbigny 337

Bifoliate zoar ium 295

Botryllopora Nicholson 384,4'JO

socialis Nicholson (84,490*

Buskopora Uh-ich 383, 4«J

( ' ' dentata Uh-ich). ..' 384,489*

lunata (Rominger) 320t,489*

BUSK'S System 5S54

Bythopora Miller and Dyer 376

' ' fruticosa 376

(Calamopora) inerustans Phillips 382,475

Callopora Hall 372, 416

( " ) aspera Hall 416

( cincinnatiensis Ulrich) 426*

elegantula Hall 372,416,417

( " ) florida Hall 416

( " ) heteropora Hall 376

( " ) laminata Half 416

( minutissima Nicholson) 427*

( missouriensis Rominger) 430*

( " ) multiseriata Hall 376

( ) nummiformis Hall 416

( " ) oculifera Hall 37ri

perelegans Hall 4J7

( " ) punctata Hall 376,42.% 130

ramosa (d'Orb) 315t,4J7

sigillarioides (Nicholson) 433

subnodosa Ulrich 308t, 417*

( " ) unispina Hall 376

Calloporella Uh-ich 373,418

harrisi Ulrich ". 3T.',U8

? nodulosa Uh-ich 418*

Calloporidae Uh-ich 339, 372

Call<5trypa Hall 376

heteropora Hall 376

multiseriata Hall 376

oculifera Hall 376

unispina Hall W8

Cancelli 238

(Carinopora Nicholson) 3fl5

Carinee 299

Caveidfe d'Orbigny .. £«

710 INDEX TO VOLUME VIII.

Cavidse d'Orbigny ............................................................................... 338

Cavea d'Orbigny ................................................................................ 666

costata d'Orbigny ....................................................................... 665

' ' regularis d'Orbigny .................................................................... 665

CeU ............................................................................................... 290

Cellaridaj .......................................................................................... 362

Cellulines ......................................................................................... 3^3

Centrifugines .................................................................................... 323

(Ceramella Hall) ................................................................................. 387

Ceramopora Hall ........... . ................................................................ 380,462

( " ) huronensis Nicholson ............................................................ 463

imbrioata Hall ................................................................ 380,463*

( " ) ohioensis Nicholson ............................................................. 466*

Ceramoporella ....................... . ....................................................... 380, 464

distinota Ulrich ............................................................ 380,464*

granulosa Ulrich .............................................................. 466*

' ' ohioensis (Nicholson) ......................................................... 466*

stellate Ulrich ................................................................. 465*

Ceramoporidas Ulrich ...................................................................... 342, 379

Ceriocava ramosa d'Orbigny ................................................................... 3181

Chffltetes ......................................................................................... 436

( " ?) carbonaria Worthen .............................................................. 445*

( " ) flliosa Nicholson .................................................................. 456*

( " ) lycoperdon Say .................................................................... 566

( " ) quadrangularis Nicholson ........................................................ 455

( " ) venustus Ulrich .................................................................... 469

Chainodioty on Foerste ..................................................................... 399,640

laxum Fcer-te .................................................................. 399

laxum var. minor Ulrich .................................................... 640*

Ghilostomata ..................................................................................... 366

Chiloporella Ulrich ...................................................... , ....................... 381

flabellata Ulrich ............................................. PI. XXXIX, flg. 5, 381

Chitotrypa Ulrich ...... ......................................................................... 382

hispida Ulrich.... ........................................... . ...................... 382

ClausidiB d'Orbigny ............................................................................. 338

Clathropora Hall ......... ................................. .............................. 349,392,4%

( " carinata HaU) ...................................................................... 496

frondosa Hall .................................................................... 392

intertexta Nicholson ............................................................. 496

Clonopora Hall .................................................................................. 368

(Coeloclema Ulrich) ........................................................................... 380, 467

Coaloconus Ulrich ...................................................................... 365,402,664

granosus Ulrich .................................................................. 665*

rhombicus Uh-ich ............................................................ 402, 664*

(Coalocaulis HaU) ................................................................................ 382

Coenoacium ....................................................................................... 290

Communication pores ...................................................................... 290,312

Constellaria Dana ........................................................................... 374,423

flscheri Ulrich .................................................................... 425

florida Ulrich .................................................................. 374,423

limitaris Ulrich ................................................................... 424

polystomella Nicholson .......................................................... 424

parva Uh-ich .................................................................... 424*

Connecting foramina ........................................................................ 290.312

Corallites, spiniform ............................................................................ 290

Coscinella Hall .......................................................................... 388,394,532

INDEX TO VOLUME VIII. 711

PAGE.

Coscinium Keyserling 385, 496

cribriforme Prout 320,497*

cyclops Keyserling 386.4%

( " cyclops Prout) 496

( ) elegans Prout 518*

( " ) keyserlingi Prout 517*

latum Ulrich 497*

( " ) michellnia Prout 515*

( " ) plumosum Prout 512*

( " ) sagenella Prout 513*

( ' ' wortheni Prout) 517*

(Coscinotrypa Hall) 385

( " carinata Hall) 496

Crepipora Ulrich 380, 469

epidermata Ulrich 471*

hemisphserica Ulrich 472*

impolita Ulrich 473

impressa Ulrich 471*

simulans Ulrich 380,470*,320t

solida Uh-ich 472*

Crescisida* 338

Crisina 337

Crisinella Hall 387

Cryptostomata Vine 344,385

(Cryptopora \icholson) 397

Ctenostomata Busk 834,367

Cyclo*tomata 335,367

Cyclopora Prout 366, 403 , 671

{ ' ' ) discoidea Prout 404, 674*

expatiata Ulrich 673

fungia Prout 366,403,671*

( ' ' jamesi Prout) 671

( ' ' polymorpha Prout) 441*

Cycloporella Ulrich 404,675

' ' ? perversa Ulrich 676*

spinifera Ulrich 404,675*

Cystiphragm 291,314

Cystodictya Ulrich 385, 486, 491 ,501,508

americana Ulrich 492, 494*

carbonaria (Meek) 492

crenulata (Hall) 4«

crescens (Hall) 492

gilbert! (Meek) 320*+, 385

hamiltonensis Ulrich 493*

incisurata (Hall) 492

invertis (Hall) 492

limata (HaU) 492

linearis (Hall) 492

lineata Uh-ich 492,494,495

var. major Ub-ich 492, 495*

" sancti-ludovici Uh-ich 492

meeki (Nicholson) 492

nitida Ulrich 493*

ocellata Ulrich 3201,385,492

ovata (HaU) 492

ovatipora (Hall) 492

712 INDEX TO VOLUME VIII.

Cystodictya parallels (Phillips) 494

perarcta (Hall) 492

pustulosa Ulrich 486,492,495*

rectilinea (Hall) 492

rigida (Hall) 492

semistriata (Hall) 492

sinuosa (Hall) 492

eubrigida (Hall) 493

sulcata (Winchell) 492, 493

trilineata (Hall) 492

tumulosa (Hall) 492

vermicula (Hall) 492

Cystodictyonidae Ulrich 346,360,385,481,486,492,496,504

Cystopora Hall 360

Defraucia '. 337

Dekayia Edwards and Haime 371,415

" aspera Edwards and Haime 372,415

' " devonica Ulrich 416*

Dekayella Ulrich 372

' ' obscura Ulrich 372

Dendricopora DeKoninck 359

Dendroid zoarium 295

Diamesopora Hall 380,467

communis Ulrich .' 469*

constricta (Hall) 468

dichotoma Hall. 381,467

infrequens (Hall) 467

oscula (Hall) 467

oweni (James) 467

subimbricata (Hall) 467

tubulosa (Hall) 467

varia (Hall) 467

vaupeli Ulrich 468*

venusta (Hall) 468

Diaphragm 291,314

Dichotrypa Ulrich 386, 498

elegans Ulrich 500*

expatiata Ulrich 501

flabellum (Bominger) 501*

foliata Ulrich 386,499*

grandis Ulrich 498*

intermedia Ulrich 500*

lyroides Ulrich 502*

Dicranopora Ulrich 338

internodia Miller and Dyer 389

(Didymopora Ulrich) 382

Dimorphic pores 302

Diploclema Ulrich 368

sparsum (Hall) 369*

trentonense Ulrich : 369*

Diplopora Young and Young 358,398,636

bif urcata Ulrich 637*

biseiial.s Ulrich 637*

marginalia Young and Young 398,637

' ' simplex -(Vine) 636

INDEX TO VOLUME VIII. 713

PAGE.

(Diploporidae Vine) 359

Diplotrypa Nicholson 378,418,457

? dubia Ulrich 379, 459*

inflda Ulrich 378.457

milleri Ulrioh 378.457

patella Ulrich 458*

perropolitant (Pander) 378,379,458

regularis Foord 457.458

westoni Ulrich 378

whiteavsi Nicholson 457

Diplotrypidae Ulrich 342,378

Discoid zoarium 295

Discopora squamata (Lonsdale) 469.471

Discotrypa Uh-ich 378

elegans Ulrich 378

Disteganopora d'Orbigny 345

Dittopora Dybowski 340

Dissepiments 291

Domopora d'Orbigny 340

D'OBBIGXY'S classification of Bryozoa 323

Drymotrypa Ulrich 399,607

ceissis (Hall) 399

dichotoma Uh-ich 399*

diffusa (Hall) 399*

niagarensis (Hall) 607

Entalophora 337

Entalophoridas Reuss 368

Eridopora Ulrich 382,463

huronensis (Nich.) 463

macrostoma Uh-ich 382

E? :-hara argyrias d'Orbigny 330t

artemis d'Orbigny 330+

Escharidze 361,366

(Escharopora Hall) 390

( ) nodosa Hall 304

Eurydictya Uh-ich 389,492,520

calhounensis Ulrich 520*

montifera Ulrieh 389, 521*

multipora Hall 521, 522

sterlingensis UTrich 522*

Euspilopora 389,526

? barrisi Ulrich 527*

palmipes (Hall) 527

serrata Uh-ich 390,526*

Evactinopora Meek and Worthen 387,508

grandis Meek and Worthen 511*

quinqueradiata Uh-ich 510*

radiata Meek and Worthen. 387, 509*

sexradiata Meek and Worthen 510*

(Favicella Hall) 384

Favositidae, no affinity to Stenopora 436

FenesteUa Lonsdale 395,535

) acmea Hall 534

( " ?) ambigiia Hall 534

bigeneris Uh- 355

714 INDEX TO VOLUME VIII.

PAGE.

Fenestella burlingtonensis" Ulrich 536*

cestriensis Ulrich 547*

cinguh.ta Ulrich 543*

compressa .Ulrich 539*

compressa var. nododorsalis Ulrich 540*

" conradi JJlrich 553*

( " (Polypora) cultellata Hall) ."8«

deUcatula Ulrich 549*

elevatipora Ulrich 549*

exigua Ulrich 545*

fllistriata Ulrich 535*

' ' flexuosa Ulrich 548*

funicula Ulrich 542*

( " hemitrypa Prout) 560*

inasqualis Ulrich 554*

limitaris Ulrich 538*

mimica Uli ich 552*

morlesta UMch 550*

multispinosa Ulrich 540*

nodosa Prout 535

( ) permarginata Hall 556

permmuta Ulrich 551*

plebia McCoy 305,537

( " ) plumosa Prout 561,562

praecursor Hall 534

quadrula'Hall 53t

regalis Ulrich 538*

reteporata Shrubsole 544

rudis Ulrich 537

( ) semirotunda Hall 556

serrata (in error for F. serratula) 545

serratula Ulrich 544*

sevillensis Ulrich 552*

tenax Ulrich 546*

( " ) thyene Hall 534

triserialis Ulrich 541*

vera Ulrich 535*

wortheni Ulrich 551*

Fenestellidae King 349,351t, 395

(Fenestellina? Waagen and Pichl) 359

Fenestralia Prout 359, 396, 004

sancti-ludoviei Prout 604,396

sancti-ludovici var. compacta Ulrich 605*

Fenestrapora Hall 395,557

biperforata Hall 395,558

occidentals Ulrich 558*

Fenestrated zoarium 296

Fistulipora McCoy 382, 474

asteria (Prout) 478

astrica Ulrich 320+.477*

( " ?) clausa Ulrich 485*

collina Ulrich 478*

communis UMch . . 382, 476*

INDEX TO VOLUME VIII. 715

PAGE.

Fistullpora compressa Bominger 488

(?Dichotrypa) corrugata Ulrieh 480*

elegans Eominger 385

( " ) flabellum Bominger 498,501*

foordi Ulrieh 315t, 479*

incrustans (Phillips) 382

{ ) lunata Eominger 384, 489*

( ) minuta Eominger 427*. 476

( ' ' minor McCoy) 382,474

( ' ' minor Nicholson) • 475

monticulata Ulrica 477*

mucosa Nichol. and Foord 474

( " ) peculiaris Eominger 386. 503*

( proporoides Nicholson) 386

( " ) occitiens Hall and Whitfleld 425

) oweni James 467

spinulifera Eominger 480*

stellilera Eominger 481*

utricu'a Eominger 477

Fistuliporidae Ulrieh 343,382,471,482,504

Flustra palmata McCoy 353

( " ) spatulata Prout 670*

( " ) tuberculata Prout 441*t,671

Frondiporidae Eeuss .- 368

Frondescent zoarium 296

(Glauconome Munster (Goldfuss)) 397,566,614,615,636

disticha Lonsdale 615

( ) elegans Young and Young 397

( (Diplopora)) marginalis Young and Young 636

( " ) trilineata Meek • 620*

(Glossotrypa Hall) , 383

Glyptopora Ulrich 387, 511

elegans Prout 518*

keyserlingi Prout 387, 517*

megastoma Ulrich 518*

. " michelinia Prout 515*

pinnata Ulrich 516*

plumosa Prout 387, 512*

punctipora Ulrich 519*

sagenella Prout 513*

sagenella var. caliculosa Ulrich 514*

sagenella var. lata Ulrich 515*

(Goniocladinas "\Viiagen and Pichl.) 360

Goniocladia Etheridge Jun 360,387

Goniotrypa Ulrich 389

bilateralis Ulrich 389

Gonrecium 290

Gonocy st 290

(Gorgonia ?) aspera Hall 639*

( " ) perantiqua Hall 405

Graptodictya Ulrich 349, 393

perelegans Ulrich 393

Gymnolaemata Allman 333,367

716 INDEX TO VOLUME VIII.

PAGE.

Hederella Hall 368

Helicopora Claypole 359. 396,580

( " archimediformis Claypole) 580.P1. LXIII.flg. 15

latispiralis Claypole 396,580

Heliotrypa Ulrioh 366, 404

bifolia Ulrich 308t, 404

Heliotrypidae Ulrich (provisional) 366,404

Helopora Hall 363, 401, 642

circe Billings 468

( " ) concava Billings 645

( " ) -.formosa Billings 645

fragilis Hall 401,643t

imbricata Ulrich 644*

lindstromi Ulrich 643t

( " ) lineata! Billings 645

( " ) lineipora Billings 645

spiniformis Ulrich 644

) striatopora Billings 645

( " ) strigosa Billings 645

( " ) variopora Billings 468

Hemitrypa Phillips 353,396,559

aspera Ulrich 563*

nodosa Ulrich 562*

oculata Phillips 396

pateriformis Ulrich 564*

perstriata Ulrich 564*

plumosa (Prout) 561,562,564

proutana Ulrich 560*

proutana var. nodulosa Ulrich 562*

proutana var. vermifera Ulrich 561*

tenera Ulrich 559

Hemiseptum 291

Hernodia Hall : 368

(Heterodictya Nicholson) 390

Heteropora Blainville 340

Heterotrypa Nicholson 371,413

frondosa d'Orbigny 371,413,414

inflecta Ulrich 1..414*

mammulata d'Orbigny 413

( ' ' mammulata Nicholson) 413

proliflca Ulrich 413*

singularis Ulrich 415*

( " ) trentonensis Nicholson 433

( " ) vaupeli Ulrich 413,421

Heterotryidae Ulrich 339,371

HINCKS, on F. A. Smitt's classification 325

Homotrypa Ulrich 370, 409

' ' arbuscula Ulrich 409*

curvata Ulrich 371

dawsoni (Nicholson) 410

flabellaris Ulrich 411*

gelasinosa Ulrich 410*

Homotrypella Ulrich 370, 412

contexta Ulrich 412*, 416

" instabilis Ulrich ..370

INDEX TO VOLUME TOI. 717

PAGE.

(Hornera?) dichotoma Hall 607

Hyolithes, bearing parasitic Bryozoa 455

Hyphasmopora R. Etheridge, Jr 366

Ichthyorachis McCoy 398

Idiotrypa Ulrich 375*

parasitica Ulrich 375

Idmonea Lamouroux 608

serpens Linnaeus 330t

Incrustine zoarium 244

Interstitial cells 290

Intrapora Hall 349, 394, 532

basalis (in error for Stictoporella basalis Ulrich) 366

" cosciniformis (Nicholson) 532*

puteolata Hall 394,532

(Intricaria) clathrata Miller and Dyer 639

( " ) reticulata Hall 639

Isotrypa Hall (emended) 353,395,534,679

ambigua (Hall) 534

conjunctiva Hall 395

gothlandica Ulrich 395,678*

(Keratophytes) dubius Schlotheim 606

Laminar zoarium 294

Leptotrypa Ulrich 377,455

flliosa CD'Orbigny) 456*

hexagonalis Ulrich 455*

minima Ulrich 378

semipilaris Ulrich — 457*

stidhami Ulrich 456*

(Lichenalia Hall) 382,475

( " ) concentrica Hall .... 475

( " lunata Hall) 489*

Lichenotrypa Ukich 383

cavernosa Ulrich 383

Lioclema Ulrich 376,425

araneum UTrich 431*

aspenim (Hall) 425,416

cellulosum (HaU) 425

foliatum Ulrich 301t,431

floridum (Hall) 416,425

gracillimum Ulrich 429*

? laminatum (Hall) 425,416

minutum (Rominger?) 427*

occidens (Hall and Whitfleld) 426*

parasiticum (Hall) 425

ponderosum (Hall) 425

punctatum (Hall) 376, 430*

singulare (Hall) 4i5

subglobosum Uh-ich 428*

wachsmuthi Uh-ich 428*

? wilmingtonense Ulrich 426*

Loculipora Hal) (Eominger MS.) 397

Lunarium. . . 291,319

718 INDEX TO VOLUME VIII.

PAGE.

Lyropora Hall 396,580

divergens Ulrich 584*

lyra Hall) 582,583

ovalis Ulrich 585*

quincuncialis Hall 396, 583*

' ' ranosculum Ulrich 581*

retrorsa Meek and Worthen 581

subquadrans Hall 582*

Macul ae 296

Massive zoarium 295

Mature and immature regions 306

Meekopora Ulrich 383, 482

? aperta Ulrich 485*

approximata Ulrich 484*

clausa (Ulrich) 315t, 485*

eximia Ulrich 383,483*

Median tubuli 290,303

Membraniporidse 366

Mesopores 290,298

Microscopic study of sections of Bryozoa 287,292

(Millepora) gracilis Phillips 402

MILLER, S. A., classification of Bryozoa, criticism of 679

Mitoclema Ulrich 369

' ' cinctosum Ulrich 369*

Mode of growth of zoarium 294

Monotrypa Nicholson 379,407,455. 462

rectimuralis Ulrich .3081,3091, 462*

subglobosa (Ulrich) 462

undulata (Nicholson) 379, 462

Monotrypella Ulrich . 377. 451

sequalis Ulrich 308t , 309t , 377, 453

appressa Ulrich 453*

' ' crassimuralis Ulrich 452*

pulchella (Edwards and Haime) 453

quadrata (Eominger) 452

subquadrata Ulrich 452

Monticulipora D'Orbigny : 370, 407

( " ) flliosa D'Orbigny 407,456

( " ) frondosa D'Orbigny — 407,414

lamellosa Ulrich 408*

mammulata D'Orbigny 370,407

( ) ramosa D'Orbigny 407

winchelli Ulrich 408*

Monticuliporidse Nicholson (Ulrich emend.) 338,369,407

Monticules 296

Mucronella spinosissima var. major Hincks 305

Multicava D'Orbigny 340

Nemataxis Hall 402

Nematopora Ulrich 363,401,406,644

alternata Ulrich 646*

concava (Bill.) 645

delicatula Ulrich 646*

formosa (Bill.) 645

fragilis Ulricn 646*

lineata (Bill.)... 646*

INDEX TO VOLUME VIII. 719

minuta (Hall) 645

Quadrata Ulrleh 401, 644*

retrorsa Ulrich 645*

striatopora (Bill.) 645

strigosa (Bill.) 645

NICHOLSON, H. A., and FOOED, A. H., on the genus Fistulipora. 474

Nicholsonella Ulrich 374,421

cumulata Ulrich 374, 423*

ponderosa Ulrica 374. 422*

vaupeli Uh-ich 421,422,423

\

Obverse face 291

(Odontotrypa Hall) 383

Ooecium 290

Operculum 291,314

Orthoceras, bearing parasitic Bryozoa 455,472

(Orthopora Hall) 402,647,662

OviceU 290

Pachydictya Ulrich 390,522

acuta (Hall) 522,526

bifurcata (VanCleve) . . 526

everetti Ulrich 523*

f enestelliformis (Nicholson) 526

var. corticula Uh-ich 526*

flrma Ulrich 525*

gigantea UMch 524*

occidentalis Ukich 522, 526

obesa Foerste 522

robusta Ulrich 390,522

splendens UMch 523*

turgida Foerste 526

Paleschara Hall 354.366

Palescharidse Ulrich .' 366

Palmate zoarium 296

Parasitic zoarium 294

Penneretepora D'Orbigny 398,615

Peronopora Nicholson 370,412

decipiens (Rominger) 370

Petalotrypa Uh-ich 377,453

compressa Uh-ich 377,454*

delicata Ulrich 454*

Petigopora Uh-ich 372

gregaria Uh-ich 372

Phacelopora Uh-ich 368, 406

constricta Ulrich 406*

pertenuis Uh-ich 368,406*

Phaceloporidae Ulrich 368

Phsenopora Hall 349,392,520

constellata Hall 392+

expansa Hall and Whitfleld 391,392t

explanata Hall 392

( " fenestelliformis (Nich. sp.) Ulrich) ._ 526*

lindstromi Ulrich 392t

( ) multipora Hall 520

Phyllodictya Ulrich .' 390,528

frondosa Uh-ich. . ..390

720 INDEX TO VOLUME VIII.

PAGE.

Phyllopora King 358,397,612

aspera Ulrich 613*

( ) corticosa Ulrich 639

ehrenbergi King 358,397,612, 613

superba Ulrich 613*

variolata Ulrich 639

( " ) sp. indet 612, PL LV, fig. 10*

Phylloporina Ulrich 399.639

corticosa (Ulr.) 639

dawsoni Ulrich 331*, 358, 639*

granistriata Ulrich 63 9 *

reticulata Hall 639

trentonensis Nicholson 639

variolata (Ulrich) 639

Phylloporinidae Ulrich 362, 399

(Pileotrypa Hall) 382,383

Pinacotrypa Ulrich 384

elegans (Eominger) 385

Pinnatopora Vine 358,397,566,614

bellula Ulr 362*. 619*

conferta Ulr 615*. 618*

elegans Young and Young 615*

flexicarinata (Y. & Y.) 620

flexuosa Ulr 617*

laxa Young and Young ; 615*

' ' . retroflexa Young and Young 615*

sedgwicki Shrubsole 627

( " ) simplex Vine 361, 636

stellipora Y. & Y 315+

striata Ulr 617*

tenuiramosa Ulr 619*

trilineata (Meek) 615*. 620*

vinei Ulr. 616*

white! Fcerste 620

youngi Ulr 615*

Pinnate Zoarium 296

Polypora McCoy 351,357,396,585

approximata Ulr 599*

arta Hall 358

biarmica Keyserling 599

( ' ' biarmica Prout) 599*

biserialis (in error for P. biseriata) 358

biseriata Ulr 315t , 538, 592*

burlingtonensis Ulr 587t

celsipora (Hall) 358

cestriensis Ulr 357, 594*

complanata Ulr 597*

corticosa Ulr -. 596*

crassa Ulrich 603*

cultellata (Hall) 586*

dendroides McCoy 397,585,607

distincta Ulrich 603*

eximia (in error for P. whitei) 600

gigantea Waagon and Pichl 603

gracilis Prout 357, 950*

grandis Toula 603

INDEX TO VOLUME VIII. 721

Polypora halliana Prout .................................................................. 357*587*

Nich) ........................................................................ 58T

incepta? Hall ...................................................... 358.(P1. LY.. fig. 1)*

koninckiana Waagen and Pichl ................................................... 604

mac-coyana TJlrich ............................................................ 357, 588*

marginata McCoy ................................................................... 602

( ' ' marginata Geinitz) ................................................................. 602*

nodocarlnata Ulrich ................................................................ 601*

radialis Ulrich .................................................................. 358. 591*

retrorsa Ulrich ..................................................................... 591*

shumardi Prout ................................................................ 397, 586*

simulatrix Ulrich ................................................................... 589*

spininodata Ulrich ................................................................. 594*

spinulifera Ulrich .............................................................. 357, 598*

submarginata Meek ................................................................ 602*

tuberculata Prout .............................................................. 857. 595*

( ' ' tuberculata Nicholson) ............................................................. 595

varsoviensis Prout ................................................................ 593*

whitei Ulrich .................................................................... 358,600*

var. insculpta Ulrich ...................................................... 600*

(Polyporidae Vine) ............................................................................... 358

(Polyporinse "Waagen and Pichl) .............................................................. 359

Polyzoarium ..................................................................................... 290

Prasopora Nicholson and Ethridge, Jr ....................................................... 371

' ' affinis Foord ........................................................................ 318t

' ' grayae Nich. & Ether .............................................................. 371

lycoperdon (Vanuxem) ............................................................. 318t

Primitive aperture ................................... .......................................... 291

Prismopora Hall .................................................................. 386,337.505,506.508

minima Ulrich .................................................................... 506*

trif olia (Eominger) ............................................................... 505*

triquetra HaU ...................................................................... 386

Proboscina Audouin ............................................................................ 368

Protocrisina Ulrich ......................................................................... 369,405

exigua Ulrich ................................................................ 369, 405*

Proutella UWch ......................................................................... 366.403,674

discoidea Prout .................................................................... 674*

(Ptilionella Hall) ................................................................................. 368

Ptilodictya Lonsdale .................................................................... 390,496,531

( " ) cosciniformis Nicholson ........................................................... 532

( ' ' expansa Hall) ....................................................................... 39H

( " ) fenestelliformis Nicholson ....................................................... 526*

lanceolata Goldfuss ................................................................ 391t

maculata Ulrich .................................................................... 317t

magniflca S. A. Miller ............................................................. 391t

nodosa (Hall) ....................................................................... 304

pavonia D'Orbigny .............................................................. 393,671

variabilis Ulrich ............................................................... 3041,317*

Ptilodictyonidje ZitteU ...................................................................... 346, 390

Ptilopora McCoy ............................................................................ 398,621

acuta UWch ........................................................................ 622*

cylindracea Ulrich .................................................................. 623*

paupera Ulrich ..................................................................... 624*

prouti HaU ...................................................................... 308, 625*

valida Ulrich ........................................................................ 623*

Ptiloporella HaU ................................................................................ 397

—90

722 INDEX TO VOLUME VIII.

PAGE.

Ptiloporina Hall ! 397

Ptilotrypa Ulrich 393,531

obliauata Ulrich 393,531*

(Ptychonema Hall) 379

Radiopora d'Orbigny 340

Eamipora Toula 360,398

Ramose zoarium 295

Reptaria Rolls 368

Retepora Imperato 612

( ) anpulata, Hall 639

( ) asperato-striata Hall 399.639

(••'.'" ) diffusa Hall 399

( " . ) flustriformis Phillips 398

( " ) trentonensis Nicholson 399, 639

( ) undala McCoy 640

Reverse face 291

Rhabdomeson Young and Young 364, 402

gracile (Phillips) 402

rhombiferum (Phillips) 661

Rhabdomesontidse Vine 363, 401

(Rhinidictya Ulrich) 388, 492, 520

Rhinopora Hall 388

' ' verrucosa Hall 388

Rhinoporidae Ulrich (provisional) 388

Rhombopora Meek 402, 647

augustata Ulrich ; 652*

? asperula Ulrich 365, 636*

' ' attenuata Ulrich 655*

crassa Ulrich 365.447

decipiens Ulrich 365,657*

dichotoma Ulrich 365.650*

elegantula Ulrich 447

exigua Ulrich 651*

gracilis Ulrich 651*

granulifera (Hall) 647

humilis Ulrich 650*

incrassata Ulrich 364, 652*

lepidodendroides Meek •. 402.651

lineinodis Ulrich 649*

minor Ulrich 364,659*

multipora Foerste 634

nicklesi Ulrich 661*

persimilis Ulrich 659*

simulatrix Ulrich 365, 657*

?spiralis Ulrich 656*

subannulata Ulrich 364. 648*

sulcif era Ulrich 649*

tabulata Ulrich 364,658*

tenuirama Ulrich 660*

transversalis Ulrich 654*

varians Ulrich 653*

wortheni Ulrich 655

Rhopalonaria Ulrich 367

" venosa Ulrich... ..367

INDEX TO VOLUME Till. 723

PAGE

(Sagenella Hall) 368

Scalaripora Hall ... 387,507

approximata Ulrich 508*

scalarif ormis Hall 3g7

separata Ulrich 507*

Scenellopora Ulrich 368

radiata Ulrich 368

See ptropora Ulrich 363, 400

facula Ulrich 40it

Sections, how to prepare them. 292

Segmented Zoarium. 296

Selenopora Hall 384

circincta Hall 384

Semicoscinium Prout 395,555

acmea (Hall) 534

{ ) infraporosum Ulr 559

permarginatum (Hall) 556

planodorsatum Ulr 555*

rhombicum Ulr 556*

rhomboideum Prout 395,555,557

semirotundum (Hall) 556

thyene (Hall) 534

Septopora Prout 397, 626

biserialis Swallow , 631*

biserialis var. nervata Ulrich 632*

cestriensis Prout 398,628*

( " cestriensis M. & W., no* Prout) 628,629

decipiens Uh-ich 630*

delicatula Uh-ich 634*

pinnata Ulrich 633*

robusta Ulrich 633*

' ' Tar. intermedia Ulrich 634*

subQuadrans Uh-ich 629*

Septa 291

SHBUBSOLE, G. W., on the Fenestellidae 353

Siphonella Hagenow 364

SJOTT, T. A., Classification of Bryozoa 325

Spatiopora Uh-ich 381

aspera Ulrich 381

Sphragiopora Uh-ich 398. 638

parasitica Uh-ich 399,638*

Sphragioporidee Uh-ich 362,398

Spiniform corallites 290

" tubuli 390

Steganopora d'Orbigny 345

Steganoporella Smitt, 345

Stellipora Hall 374

antheloidea Hall 375,423

Stenopora Lonsdale 375, 436

americana Uh-ich 30yt.437*,438.439

americana var. varsoviensis Ulrich 437*

angularis Ubrich 43 9*

' ' carbonaria (Worthen) 445*

' ' carbonaria var. conferta Ulrich 445*

' ' carbonaria var. maculosa Ulrich 445*

724 INDEX TO VOLUME VIII.

PAGE.

Stenopora oestrienslsJTJlrlch 442*

emaciata Ulrich 438*

( ' ' flbrosa Goldfuss) 288

intercalaris Ulrich 439*

intermittens Ulrich 440t

meekana Ulrich 443*

montifera Uh-ich 438*

( ' ' polymorpha Prout=S. tuberculata Prout) 444,671

ramosa Ulrich 365, 442*

rudis Ulrich 444*

? signata Ulrich 365, 446*

tasmaniensis Lonsdale 375

tuberculata (Prout) .* 3151.438,441*+

Stictopora Ulrich (Hall, 1847) 388,491

( " Hall, 1886) 491

( " ?)acuta Hall 491

( " ) crenulata Hall 492

( " ) crescens Hall 492

( " ) elegantula Hall 491

fenestrata Hall 388,492

( " ) gilberti Meek 492

glomerata Hall 491

( " ) incisurata Hall 492

{ " ) Invertis Hall 492

labyrinthica Hall 491

( " ) limata Hall 492

( " ) linearis Hall 492

( " ) meeki Nicholson 492

mutabilis UMch 304t

nicholsoni (Uh-ich) 492

( " ) ovata HalL 492

( " ) ovatipora Hall 492

( " ) palmipes Hall. 527

( " ) perarcta Hall 492

( " ) punctipora HalL 394t

ramosa Hall 491,492

( " ) rectilinea Hall 492

( " ) rigida HaU 492

( " ) semistriata Hall 492

( ' ' ) shafferi Meek 393

( " ) similis Hall 393,394t

( " ) sinuosa,Hall 492

( " ) subrigida Hall 492

( " ) sulcata Winchell 492

( ' ' ) trilineata Hall 492

( " ) tmnulosa Hall 492

( " ) vermicula Hall i 492

Stictoporella Ulrich 394,532

basalis Ulrich * 532*, 727

interstincta Uh-ich 394

(?) undulata UMch 533*

Stictoporidas UMch (emended) 347, 388

Stictotrypa UMch 349, 393

' ' punctipora (Hall) 394t

similis (Hall) 393,394t

INDEX TO VOLUME VIII. 725

PAGE.

Stomatopora" Bronn gg^

dlchotoma Lamx ..367

Streblotrypa Ukieh, 403 ggj

distincta Ulrich 669*

major Ulrich ...666*

nicklesi Ulrich 408,667*

radialis Ulrich 667*

' . sabspinosa Ulrieh 668*

StreblotrypidEe Ulrich 365^ 402

Strophomena, bry ozoan growing on 41g

Strotopora Ulrich 383,486

dermata Ulrich 488*

foveolata Ulrich { 383,487*

perminuta Ulrich 487*

Structure of Bryozoa 292

Superficial aperture 291

Synocladia King 398.627

( " ) biserialis Swallow 531

virgulacea King 398,627

( " virgulacea? Swallow) 631

Tabute 291

Ta?niodietya Ukich 393, 528

cingulata UMch 304t, 530*

frondosa Ukich 529*

ramulosa Ukich 393, 528*

var. burUngtonensis Ukich 529*

subrecta Ukich. 530*

Taeniopora Nicholson 386,504

exig-ua Nicholson 505

occidentalis Ukich 505*

penniformis Nicholson 386.505*

Tectulipora HalL 679

Terminology 290

(Thallostigma Hall) 382,475

(ThamniscidEe King) 358

Thamniscus King 897, 606

( " ) cisseis Hall 399

crassus (Lonsdale) 607

dichotoma Hall 607

divaricans Ukich 357. 608*

dubius (Schlotheimj 357,397,606

furcillatus Ukich 609*,637

gracilis Vine 610

( ' ) niagarensis Hall 399,607

octonarius Ulrich. 611*

ramulosus Ukich. 357, 607, 610*

var. sevillensis Ukich (now regarded as a species) 610*. 727

sculptilis Ukich 608*

serialis Waagen and Pichl 608

sevillensis Ukich 610*. 727

Thamnotrypa Hall 387

Trematopora Hall 373.418

calloporoides Ukich 420*

( " ) constxicta Hall 468

debilis Ukich 419*

( " ) granulifera Hall ..647

726 INDEX TO VOLUME VIII.

PAGE.

(Trematopora) minuta Hall 645

? nltida Ulrich 419*

' ' primigenia Ulrich 419, 420

tuberculosa Hall 374.418

( " ) venusta Hall 468

Trematoporidse Ulrich 340. 373

Trepostomata Uh-ich 337,369

Tropidopora Hall 402

Tubuli median 290.303

" spiniform 290

TubuliporidEe Busk 367

UnitrypaHaU 396.534,679

lata Hall 396

Vesicular tissue 290,298

Vesicularidae 334

Vincularia Defrance 615

Vlncularidae 363.364

VINE, Q. B., on the PenestellidaB 358

WaU inflections 320

Wall structure of zooacia 306

Wandstrange '. 290

Wandrohrchen 290

Worthenopora Ulrich 403.669

' ' spatulata (Prout) 670*

spinosa Ulrich 669*

Zoarium 290,294

Zocecium 290,306

INDEX TO VOLUME VIII. 727

ERKATA IN SECTION 6.

Page 320, 3d line from top. for OCCellata read OCellata.

Page 320. 6th line from bottom, for Cribriform! read cribriforme .

Page 321,10th line from bottom.for hill read Mill.

Page 324,16 and 17th line from bottom.for Fenestrella read Fenestella.

Page 335,18th line from bottom, for exert read GXSert.

Page 344, 8th line from bottom of note, for of Joredale read on Yoredale.

Page 350,10th line fiom bottom, for SGCton read Section.

Page 357, 16th line from top, for geneO- read genea-

Page 358. 2d line from bottom.for biserialis read biseriata.

Page 366,9th line from top.for Intrapora basalis read Stictoporella
basalis.

Page 368, in note at bottom.for Bolle read by Rolle.
Page 369,12th line from top, for exerted read exserted.
Page 394, in explanations to flg. 14, transpose a and b.
Page 394,11th line from bottom, for Cosinella read Costinella.
Page 397,3d line from top, for Scbumardi read Shumardi.
Page 420.10th line from bottom.for PI. XXXIV read PI. XXXVIII.
Page 453, 2d line from top, for PI. XLIV read PI. XL VI.

Page 469, add the following note, Ch&tetes venustus Ulr., Journ. Gin. Soc. Nat. Hist.
Vol. l.p. 93, PI. IV, flg. 7, 70,1878. (This note, in part, occurs erroneously on page 470.)
Page 489, 19th line from bottom, for PI. XLVII read PI. XLVIII.
Page 492,4th line from bottom in note, for fenestruta read fenestrata.
Page 515,19th line from top, for flg. 4 read flg. 7.
Page 527, llth line from bottom, for fig. 1— lb read 1— It.
Page 532,3d line from bottom, for fig. 5-5 b read 5-5c,

and add. PI. LXVIII, fig. 5, 5a, and LXIX. fig. 2, 2a.

Page 578,14th line from bottom for plaCG read space.

Page 600,9th line from bottom for P. exiwia read P. whitei.

Page 610,6th line from bottom, for var. SEVILLENSIS read THAMNISCU8 SE-

VILLENSI8; and modify the description and remarks so that they will accord

with this change.

Page 620,14th line from top, for XL VI read LVI.
Page 623,2d line from top.for figS. 5-5c read 5~5b.

Page 643, in explanation to flg. 18, for flg. a read c; for c read d; for d read e; for e read a
Page 647, 3d line from top, for 0.2 mm. read 2 mm.
Page 653,15th line from top.for fig. 1-lb read fig. 1-lf.

728 INDEX TO VOLUME VIII.

TABLE OF CONTENTS.

SECTION 6.

PAGES.

Letter of Transmittal 285-286

Preface 287-290

Terminology 290-291

General and Comparative Structure of Palaeozoic Bryozoa 292-322

Classification and Interrelation of Families and Genera 323-366

Synopsis of Classification 367-404

Descriptions of Species 405-677

Addenda t>78-688

Index 707-727

Errata 727

Table of Contents 728

Explanations of plates.

ILLUSTRATIONS.
Plates XXIX-LXXVIII,
Eighteen woodcuts in the text.

APPENDIX.

(Geological Surrey of Illinois. Yol. VIII.)

THE PRIVATE LIFE

AND

SCIENTIFIC WORK

OF

PROF, AMOS HENRY WORTHEN

BY

X. W. BLISS AND CHARLES A. WHITE.
WITH A PORTRAIT BY JACQUES REICH.

No. 6646 WBNTWOBTH AVENUE,
ENGLEWOOD, ILL., December 22, 1888.

PROF. JOSUA LINDAHL, State Geologist,

Springfield, 111.:

DEAR SIR — In response to your request that I should prepare
for the Eighth and final volume of Prof. Amos H. Worthen's
Reports upon the Geology of Illinois, a biographical notice of
the learned and lamented author, I beg to submit the enclosed
account of his life and estimate of his personal and scientific
character; and to remain, most truly,

Your obedient servant,

N. W. BLISS.

A Sketch of the Private Life and Personal and Scientific Character

PROF, AMOS HENRY WORTHEN,

BY N. W. BLISS.

Prof. AMOS HENRY AVORTHEX, State Geologist of Illinois and
Curator of the State Historical Library and Museum of Natural
History, died at his home in Warsaw, Hancock county, Illinois,
on Sunday. May 6, 1888, of pneumonia, at the ripe age of
nearly seventy-five years. For over thirty years he had been
constantly engaged, first, in the survey of, and then in writing
and publishing the reports upon, the geology of his great
adopted State; and his work has been of such a thorough and
able character, that while it has made for him a name honored
among the scientists of the world, his volumes have long been
text books of palseontological nomenclature. Just prior to his
death he had completed and prepared for publication his eighth
and final volume of Reports upon the Geology of Illinois, and
was anticipating a period of rest as soon as by means of a
suitable appropriation this final volume should be published
and off his hands, having determined then to resign the place
in the service of the State which he had so long and ably filled.
But death came all too soon and found the busy man still in
harness, and the period of earthly activity was exchanged for
one of heavenly rest.

Amos Henry Worthen was born at Bradford, Orange county,
Vermont, October 31, 1813. He was the son of Thomas Wor-
then and Susannah Adams, his wife, and was the younir*jst.
save one, of a large family of thirteen children. His mother,

8

{Susannah Adams, was the daughter of Abraham Adams, who
married Mary Brickett, and was a descendant of Henry Adams,
the founder of the Adams family in America, who settled at
Mount Wollaston (now Quincy), Massachusetts, and to whose
memory his descendant, President John Adams, erected a plain
granite monument with this quaint inscription:

"In memory of Henry Adams, who took his flight from the
dragon persecution, in Devonshire, England, and alighted with
eight sons near Mount Wollaston. One of the sons returned to
England after taking time to explore the country. Four re-
moved to Medford and the neighboring towns. Two to Chelms-
ford. One only remained, Joseph, who lies here at his right
hand, who was an original proprietor in the Township of Brain-
tree, incorporated in the year 1639."

Susannah Adams, the mother of Prof. Worthen, was a woman
of a most amiable disposition, and at the same time of great
mental and physical activity and force. A mother with these
characteristics seldom fails to transmit them to her posterity.
His father, Thos. Worthen, was the owner of a farm upon what
was known as the South Road, in Bradford, where were
"brought up" (not "raised") this large family of sons and
daughters. Here Prof. Worthen gained the first rudiments of
his education in the excellent common schools of his native
State, and his early physical training, of almost equal import-
ance to his future usefulness in his chosen profession, in labor
upon his father's farm. At that time the academy at Bradford
Village was an institution of learning of a high class, and here
Prof. Worthen finished his school training, boarding for that
purpose at the home of his sister, Mary, who married Capt.
Ellis Bliss, an extensive farmer in the Connecticut Valley. At-
tending the same school, from the same house, bearing the re-
lation of uncle and nephew, he finishing, and the writer begin-
ning his academic course, a friendship and intimacy began which
lasted from that period to the day of his lamented death. At
an early age, before arriving at his majority, he married, Janu-
ary 14, 1834, Miss Sarah B. Kimball, of Warren, N. H., who
was his faithful and life-long companion, preceding him to the
better land only a little over a twelve-month. At that time
Ohio and Kentucky were the far west, and it required a high

degree of courage and determination for the young New Eng-
lander to risk his fortunes in those strange and distant lands.
But. as with so many others, Prof. Worthen was not without
friends and even relatives in the distant west. His eldest
brother, Enoch, was then living at Cynthiana, Kentucky, where
he had settled and founded a family, and thither the young
emigrant betook himself. Whatever else the average New Eng-
lander may or may not be capable of doing, one thing, for
want of better, or rather more remunerative employment, they
have almost universally engaged in, in all the new countries
which they have helped to settle and civilize, and that is, school
teaching. Prof. Worthen, then a plain Yankee lad, without
title, was no exception to the rule, but began his western life
and experiences in teaching school at Cummiusville, Ohio, then
in the wilderness — though now a suburb of her chief city, Cin-
cinnati. Remaining here two winters, in June, 1836, he took
his wife and infant son to Warsaw, Illinois, where he made his
permanent home. Here he has done his life's work, and hence
he has entered into (well earned) rest. Meanwhile his wife's
family (the Kimballs) had also emigrated to the west, making
their home on Bear Creek, in Hancock county, and with his
brothers-in-law, the Kimball boys, or one of them, Prof. Wor-
then became first a forwarding and commission merchant, oc-
cupying and residing in the warehouse and dwelling standing
on the site now occupied by the mill of the Warsaw Milling
Company, known as Grace mills, later occupying the brick cot-
tage which he built, and conducting a dry goods business upon
the hill at Warsaw. In 1842, influenced by the depression in
business caused by the Mormon difficulties in Hancock county,
he removed with his family to Charlestown, Mass., and here his
son. Amos Henry Jr., was born. He was probably influenced
in his second removal (that from Ohio) to select Warsaw as
his future home, by the fact that his wife's family had selected
this region as their western home, but had his predilections for
the life of a naturalist been known and their stimulation an-
ticipated, no region could have been selected better calculated
to awaken and sustain the enthusiasm of a naturalist. As
stated by himself on page 89 of his first volume of Reports
upon Geology of Illinois: "A fine section of the geode bed is
—2

10

exposed just above the steamboat landing at Warsaw, where
its whole thickness may be seen in the bluff above the railroad
grade, and there is perhaps no locality known in the west
where a few hours labor of a good collector would be rewarded
by so large a variety of finely crystallized specimens. There is
no formation in the State that presents such attractive and in-
teresting specimens of crystallized minerals as are to be found
in this division of the Keokuk limestone, and tons of these
beautiful geodes have been sent from the county of Hancock
to adorn the cabinets of mineralogists throughout the civilized
world." It may be added that by far the largest portion of
these shipments have been sent abroad by Prof. Worthen him-
self. One can easily imagine what an impetus such surround-
ings would give to a love of nature already abounding, and to
powers of observation and analysis already somewhat trained
and cultivated by study and travel, accordingly his attention
from the first was strongly attracted to the geological features
of his new home, and its geode beds at once commanded his
admiration and close investigation. Even at that early period
he felt stirring within him that spirit of investigation and love
for natural science that later caused him first to neglect and
then to abandon entirely all business less suited to his taste,
and to devote himself to science with a singleness of purpose
and devotion as rare as it is honorable to the individual and
advantageous to mankind. He gathered and took with him to
Boston several barrels of the splendid crystallizations called
"geodes," then rare in collections, and there, instead of selling
them, with a naturalists true love for his (to be) calling, ex-
changed them for a cabinet of sea shells, which he brought
back with him to Warsaw when he returned there in July, 1844.
Similar forms to these shells he saw everywhere preserved in
the limestone rocks and shales of his neighborhood and every
spare hour found him with his hammer and satchel exploring
every ravine, bluff and quarry and every exposure of the sub-
jacent rocks which could be reached. He was consumed with a
desire to know something of their history and nomenclature.
The science of geology may be termed a child of the nine-
teenth century, during which more progress has been made in
the knowledge of the history of the earth than during all pre-

11

ceding time. When Prof. Worthen took up the study, amid the
cares of a family and while engaged in business, the facilities
for its study were extremely few especially in the western
country. No work on elementary Geology had then been pub-
lished in this country and the first books that he was able to
obtain were Dr. Mantell's "Medals of Creation" and "Wonders
of Geology,'' which I well remember finding in his library upon
my arrival at his house in the spring of 1850. They were
written in a style adapted to popular comprehension and by
as great an enthusiast and collector as himself. It is doubtful
if any works could be found now, better calculated to stimu-
late the zeal of a born naturalist. They presented a general
survey of the Fossil World, with an outline of British Paleon-
tology, illustrated by wood cuts of fossil remains. It gave him
what he most needed at the time, an insight into the manner
in which the sedimentary rocks were formed and howr the re-
mains of animals and plants came to be embedded and pre-
served in them. By collecting the minerals and fossils in his
own locality and exchanging them with other collectors for
those found elsewhere, he gradually gathered not only an ex-
tensive and very valuable geological museum but acquired the
knowledge which was the object of his ardent pursuit. Thus
the writer found him upon his own arrival in the Mississippi
Valley in the spring of 1850. He was still engaged in business
but his store as well as his house was more of a stone shop
than a dry goods shop and he evidently begrudged the time
there spent waiting for or attending upon customers; conse-
quently he soon sold out his business and determined for the
future to devote himself to his loved science. Meanwhile by his
correspondence and exchanges he had made the acquaintance
of many men engaged like himself in scientific pursuits and
made such progress himself in knowledge as to be elected a
member of the American Association for the Advancement of
Science at its 5th annual meeting, held at Cincinnati in 1851,
a society of which he remained a member to the time of his
death, whose proceedings he greatly enjoyed, and to whose trans-
actions he at various times contributed valuable papers, notably
"On the occurrence of fish remains in the carboniferous limestone

12

of Illinois", "Remarks on the discovery of a Terrestrial flora
in the Mountain Limestone of Illinois," and "Remarks on the
relative age of the Niagara and the so-called Lower Helderberg
groups."

January 16, 1863, Prof. Worthen was made a member of the
"American Philosophical Society of Philadelphia."

October 15, 1871, he was appointed correspondent of "The
Imperial Royal Geological State Institute of Vienna."

April 17, 1872, he became a member of the "National Aca-
demy of Sciences, U. S. A." And on May 20, 1873, of the
"Societe Royale des Sciences de Liege."

He was probably a member or correspondent of other learned
scientific bodies, but he was careless of such honors, paying
more attention to furnishing the scientific world through the
membership of these societies, with new facts and discoveries,
than to receiving from them indorsements or honors. Before
these scientific bodies he read or to them he communicated at
various times, important papers relating to his investigations
and discoveries in the Lower Carboniferous Limestones, some of
which will be found published in the transactions of the St.
Louis Academy of Sciences, of the American Philosophical So-
ciety of Philadelphia and in the American Journal of Science
and Arts, edited by Silliman, specimens of these communications
are found in his remarks on the age of the Leclaire Limestone,
at Leclaire, loAva, and Port Byron, Illinois, Vol. 33, Silliman's
Journal, and Remarks on the Age of the Goniatite Limestone
at Rockford, Indiana, Vol. 32, Silliman's Journal, a joint paper
by himself and the learned palaeontologist Prof. F. B. Meek,
whom he had so closely associated with himself in the Palseon-
tology of the Illinois Survey.

Prof. Worthen was not given to "rushing into print" and ex-
cept for the purpose of preserving priority of description and
nomenclature of the fossils collected and described in the reports
of the Illinois Survey, seldom published anything unless he had
some important fact or discovery or well considered conclusion,
to present to the scientific world.

The Illinois Legislature in February, 1851, passed an act
authorizing a geological survey of the State, appropriating
|3,000.00 a year for that purpose, and two years later increased '
this appropriation to $5,000.00 per annum. Prof. Norwood, a

13

Scientist of repute, who had been associated with the noted Scientist
Prof. Owen, of Indiana, was appointed Geologist, and for a
while Prof. Worthen did some work under him, but soon en-
gaged in more active work in Iowa under Prof. James Hall of
New York, who having just finished the survey of his own great
State was called to that of Iowa, which State had, in 1855,
passed an act authorizing a survey which was promptly com-
menced in September of that year. Prof. Hall in his first re-
port says of Prof. Worthen that "he was engaged as assistant
at the commencement of the survey and was employed during
the seasons for exploration until the close of 1857; by his ser-
vices in the field and the loan of his magnificent collection of
carboniferous crinoids he has added greatly to the value and
interest of this report/'

His first work here was a series of examinations along the
DesMoines Valley and the eastern border of the Iowa coal field
made with a view of determining the number, thickness and
relative value of the different coal seams outcropping in that
part of the State, upon which he duly reported and the next
year (1857) he made minute examination of and report upon the
geology of certain counties in southeastern Iowa. This consti-
tuted all the detail work of that survey, only the leading feat-
ures of the remaining counties establishing the outlines of their
geology being given.

Meanwhile the work in Illinois languished: although six years
had elapsed since the passage of the act authorizing the survey,
no report had been made, and when on March 22, 1858, Gov.
Wm. H. Bissell placed in the hands of Prof. Worthen his com-
mission as State Geologist, nothing of prior work came to his
hands save a report by Prof. Norwood on the lead mines of
Hardin county, and the field notes of his assistants. On taking
charge of the survey Prof. Worthen at once proceeded to those
active labors in the field, in prosecuting which he has probably
carried a greater bulk and weight of geological specimens than
any other scientist of his day. During his long period of pre-
paration by personal exploration and study of the geological
formations of his vicinity and by the extensive system of ex-
changes he established with other collectors at an early day, he
had been enabled to gather, classify and arrange the largest
and best geological museum in the west. By his minute and

14

careful examination of the rocks of his region he had discovered
those "platforms of death" as he well named those crowded
masses of remains of fossil fishes which he found in the thin
strata of the lower Archimedes limestone. One specimen found
by him in this prolific locality proved to Prof. Agassiz that he
was correct in his conclusions already drawn from comparative
anatomy, and he stated that it enabled him as upon an estab-
lished basis of fact (not reasoning) to take up his studies of
fossil fishes anew and pursue them further than ever, and he
had portions of this collection long in his possession. This
minute and careful personal examination and observation of
the different strata and abundant collection of specimens re-
dounded greatly to the advantage of his collection which con-
sequently contains a greater number of what may be called
type-specimens than any other collection. From it were selected
almost wholly the specimens with which to illustrate the re-
ports upon Paleontology of Iowa and the same is largely true
also of the volumes of the Illinois reports. He had also during
these years gathered together a scientific library of great value.
The writer well remembers how he exercised a severe economy
in other directions to enable himself to purchase the rare and
expensive books needed for his studies in his favorite field.
Wherever a book was to be had in exchange for specimens it
was obtained regardless of expense in the way of payment for
it, and where money was required it was freely expended. Thus
well equipped, both by personal experience in the field, and by
the study of actual specimens as well as of books, he came to
his life work of which it is enough to say that it has been done
with characteristic thoroughness and fidelity, and reported with
an ability and minuteness that have made his reports text
books of the Palaeontology of Illinois, and a monument of his
own industry and ability. Professor Worthen like General
Grant, never withheld the meed of praise and credit from his
assistants and co-laborers. He had the countenance, support
and friendly aid of numerous lovers of science in all parts of
the State. He also secured for the work the aid and assistance
of the ablest specialists of the day in every department, notably
Prof. J. D. Whitney in mineralogy, Prof. Leo Lesquereux in
coal measures and coal plants, Profs. F. B. Meek, Orestes St.
John, Dr. John S. Newberry and Mr. E. O. Ulrich in different

15

departments of Palaeontology, Dr. J. V. Z. Blaney in analysis
and Mr. Henry Engleman in chemistry and detailed county
work.

There were born to Prof. Worthen and his wife Sarah, six
sons, all of whom survive him, and one daughter, whose death in
early years was mourned during their whole lives. He had a
happy and prosperous home and the companionship and support
of a faithful and noble wife. All the sons are worthily married
and twenty-two grand children are growing up in the light and
succession of an honorable name. The six sons, Fay S., George
B., Thomas A., A. H. Jr.. Charles K. and John B. were their
honored fathers's pall-bearers, and by them were his remains
placed in the tomb at Oakland Cemetery at Warsaw. All are res-
idents of Warsaw save Fay S., who, since his father's death, has
removed to Denver, Colorado. As was natural in a family where
the head was so entirely devoted to scientific observation, all the
sons and some of the grand-children as well became imbued to
some degree with the father's enthusiasm and in all of them the
powe and practice of close observation of nature and natural
objects, is developed to an unusual degree. One of them, Charles
K., has devoted himself to natural science and is now a naturalist
and taxidermist of note residing at Warsaw. He it was, who
made the fine pencil sketches for the engraver, which have given
the numerous volumes of the Illinois survey their admirable
illustrations.

Mr. Edward O. Orich, formerly one of his assistants in
the Illinois survey, says of him, "Prof. Wort-hen's labors
related principally to the carboniferous series. To him belongs
the credit of being the first to work out the true relations of
the principal divisions of the lower carboniferous system, though
the inflexible rules of priority may demand that the names pro-
posed by other laborers in this field should stand for them."

"The value of his work was recognized by his election as an
honorary member of several European scientific societies as well
as a membership of various scientific societies in his own
country."

Regarding his character; Prof. Ulrich who had an unusually
good opportunity to form a sound opinion, says, "Its salient
features were: great love for scientific truth and justice, sim-
plicity, unbounded affability, unswerving integrity, coupled with

16

an unpretentious yet strong desire to accomplish a useful career.
His generosity and charity scarce knew bounds, while in his
public and private life his frank and sympathetic nature and
unassuming yet dignified demeanor won the esteem of all with
whom he came in contact.

This seems to me, having known him all my life, an estimate
at once terse and just.

Like Dr. G. A. Mantell, the author of the first works on Geo-
logy, Prof. Worthen was able to obtain, "his most important
discoveries sprang out of the researches he never ceased to pur-
sue among his favorite group of rocks — the Lower Carbonifer-
ous. His location at an early period of his professional career,
was exceedingly favorable for these inquiries, and as stated by
Prof. Ulrich he was assuredly the original demonstrator of the
true relations of its principal divisions. With the Lower Car-
boniferous series also are connected his chief and very memor-
able palaiontological discoveries, out of that formation he pro-
cured those wonderful fish remains so highly regarded by Prof.
Agassiz as well as the evidences of Terrestrial Flora there im-
bedded as announced in his paper read before the 13th meeting
of the American Association for the advancement of science.

I feel that I cannot close this biographical notice of Prof.
Worthen without calling attention to characteristics that, to my
mind, rendered him a brother indeed to that great naturalist
he so much admired and loved, Prof. Agassiz. He had the same
intense love of natural science with that great teacher. Like
him, he could not exist without collecting a museum. He had
the same remarkable powers of instant observation. Like him,
he gathered and brought home from the formations to which
he devoted his life work a greater variety and collection of fossil
remains than have ever before or since been collected by one in-
dividual. He had the same disinterestedness, the same conse-
cration to science, the same readiness to oblige even the hum-
blest and most modest, the same superiority to self-interest, the
same sincerity and absence of all pretension, and the same en-
thusiasm in all that was noble. As with Agassiz, so with
Worthen, never was a life more richly filled with study, work
and thought. Like Agassiz, Worthen had no time to make
monev.

17

In one of his, letters home. Agassiz said: "If I could for a
moment forget that I have a scientific mission to fulfill I could
easily make more than enough by my lectures to put me com-
pletely at my ease, but I will limit myself to what I need to
repay those who helped me through a difficult crisis. Beyond
that all must go to science — there lies my true mission."

So said Prof. Worthen in deed, if not in words. I well re-
member his only anxiety for money was to pay some balances
on his mercantile debts, and these he paid out of his salary
earned in his early employment in geological surveys, and as
with his great exemplar, all beyond that "went to science." As
said by me in the obituary notice of him published in the War-
saw (111.) Bulletin just after his decease, Prof. Worthen was,
Like most men who become eminent in any special work, en-
tirely devoted to that work, and counted all else as dross in
comparison with results to be obtained in his favorite field of
investigation, and the result with him, as with such men in all
ages, has been a long, honorable, industrious and useful life,
and an honored and lamented death.

—3

18

A Sketch of the Scientific Work

PROF, A, H, WORTHEN.

BY CHARLES A. WHITE.

Professor Worthen began the work which has made his name
so widely known at a time when little had yet been done in
geological science in our country, and he prosecuted it almost
without interruption until his death in 1888. Like most of the
earlier American naturalists, he began his scientific work as an
amateur, and under difficulties that the younger naturalists of
to-day, who have had the advantage of special training in
scientific schools, and who have free communication with a
multitude of scientific workers, cannot well understand.

His home being upon the Lower Carboniferous rocks of west-
ern Illinois, his opportunities were good for the study of their
fossils and their stratigraphical relations; and it was doubtless
this circumstance that gave bent to his future career. In the
prosecution of his private studies he made many extensive jour-
neys in the region traversed by the Upper Mississippi river, and
brought together some of the finest collections of fossils from
the formations there that have ever been obtained.

His first public work was performed sometime about the year
1853, as an assistant to Dr. J. G. Norwood, then State Geolo-
gist of Illinois, but little or no record of that work has been
preserved. In 1855 he was appointed assistant to Prof. James
Hall, then State Geologist of Iowa, and continued upon that
work until its suspension in 1858. Besides contributing two
important chapters to Professor Hall's report upon the geology
of that State, he aided largely in constructing the geological
section along the Mississippi river, from Lansing to St. Louis,
which is published in that report.

19

In 1858 he was appointed State Geologist of Illinois by Gov.
W. H. Bissell; and in connection with this office he performed
the work which has been of so much honor to himself and
credit to the State. From the time of his appointment, to the
end of his life, he devoted himself to the State of Illinois almost
exclusively, for he found there an ample field, not only for his
own labors, but for those of all the assistants whose services
he could obtain.

Upon entering upon the duties of his office he quickly com-
prehended the magnitude of the task that lay before him, and
he began to gather about him men skilled in various branches
of scientific work, among whose names are many that are
familiar to the whole scientific world. The following is a list of
those who have aided him in his work, and who have con-
tributed their writings to his reports and other publications:
Bannister, Dr. H. M. Lesquereux, Dr. Leo

Barris, Prof. W. H. Meek, F. B.

Blaney, Dr. J. V. Z. Miller, S. A.

Bradley, Prof. F. H. Newberry, Prof. J. S.

Broadhead, Prof. G. C. Prout, Dr. H. A.

Cope, Prof. E. D. Scudder, S. H.

Cox, Prof. E. T. Shaw, James

Englemann, Henry Springer, Frank

Everett, Dr. Oliver St. John, Prof. Orestes

Freeman, H. C. Ulrich, E. O.

Green, H. A. Wachsmuth, Charles

Whitney, Prof. J. D.

After his field work upon the State Survey had been accom-
plished, Professor Worthen was appointed Curator of the State
Historical Library and Natural History Museum. In connec-
tion with the duties of this office he continued the preparation
of the remaining results of his work on the survey for publi-
cation, which have appeared in Bulletin No. 1 of the Museum,
and in the two last volumes of his great series.

The following is a list of the works which have been pub-
lished by him, portions of which have appeared under his name
alone, and other portions under the names of certain of his
assistants respectively; but his name appears as joint author
of the greater part of the work of his assistants.

20

BIBLIOGRAPHY.

1. A. H. WORTHEN.

On the Occurrence of Fish Remains in the Carboniferous
Limestone of Illinois. Proc. Am. Assoc. Adv. Sci., 10th
meeting, Albany, N. Y., pp. 189-191, Cambridge, 1857.

2. A. H. WORTHEN.

Geology of the Des Moines Valley. In Report Geol. Sur-
vey of Iowa, by JAMES HALL; Vol. 1, part I, pp. 147-182,
1858.

3. A. H. WORTHEN.

Geology of certain Counties, embracing the results of ex-
aminations in the counties of Lee, DesMoines, Henry, Van
Buren, Jefferson, Washington and Wapello. In Report
Geol. Survey of Iowa, by JAMES HALL; Vol. I, part I,
pp. 183-258, 1858.

4. A. H. WORTHEN.

Remarks on the Discovery of a Terrestrial Flora in the
Mountain Limestone of Illinois. Proc. Am. Assoc. Adv.
Sci., 13th Meeting, Springfield, Mass., pp. 312-313, Cam-
bridge, 1860.

5. A. H. WORTHEN.

Notice of a new species of Platycrinus and other fossils
from the Mountain Limestone of Illinois and Iowa. In
Trans. St. Louis Acad. Sci., Vol. I, pp. 569-571, 1860.

6. A. H. WORTHEN; F. B. MEEK and

Descriptions of new Carboniferous fossils from Illinois and
other Western States. In Proc. Acad. Nat. Sci. Phila.,
Vol. IV, 2d ser., pp. 447-472, 1860.

7. A. H. WORTHEN; F. B. MEEK and

Descriptions of new species of Crinoidea and Echinoidea,
from the Carboniferous rocks of Illinois and other West-
ern States. In Proc. Acad. Nat. Sci. Phila.. Vol. IV, 2d
ser., pp. 379-397, 1860.

21

8. A. H. WORTHEX; F. B. MEEK and

Remarks on the age of the Goniatite Limestone at Rock-
ford, Indiana, and its relation to the "Black Slate" of
the Western States, and to some of the succeeding rocks
above the latter. In Am. Jour. Sci., Vol. XXXII, 2d ser.,
pp. 167-177, 1861.

9. A. H. WORTHEX: F. B. MEEK and

Descriptions of new Palaeozoic fossils from Illinois and
Iowa. In Proc. Acad. Xat. Sci. Phila., Vol. V, 2d ser.,
pp. 128-148, 1861.

10. A. H. WORTHEX.

Remarks on the age of the so-called "LeClaire Limestone"
and "Onondaga Salt Group" of the Iowa Report. In
Am. Jour. Sci., Vol. XXXIII, 2d ser., pp. 46-48, J862.

11. A. H. WORTHEX: F. B. MEEK and

Note in relation to a genus of Crinoids from the Coal
Measures of Illinois and Nebraska, proposed on page 174
of this volume of the Journal. In Am. Jour. Sci., Vol.
XXXIX. 2d ser.. p. 350, 1865.

12. A. H. WORTHEX; F. B. MEEK and.

Notice of some new types of organic remains, from the
Coal measures of Illinois. In Proc. Acad. Nat. Sci., Vol.
IX, 2d ser. pp. 41-53, 1865.

13. A. H. WORTHEX: F. B. MEEK and.

Remarks on the genus Taxocrinus (Phillips) McCoy, 1844;
and its relations to Forbesiocrinus, de Koninck and Le
Hon, 1854, with descriptions of new species. In Proc.
Acad. Nat. Sci. Phila. Vol. IX, 2d ser. pp. 138-143, 1865.

14. A. H. WORTHEX; F. B. MEEK and.

Descriptions of new species of Crinoidea, &c., from the
Palaeozoic rocks of Illinois and some of the adjoining
states. In Proc. Acad. Nat. Sci. Phila. Vol. IX. 2d ser.
pp. 143-155, 1865.

15. A. H. WORTHEX: F. B. MEEK and.

Contributions to the Palaeontology of Illinois and other
Western States. In Proc. Acad. Nat. Sci. Phila. Vol. IX,
2d ser. pp. 245-273, 1865.

22

16. A. H. WORTHEN; F. B. MEEK and.

Contributions to the Palaeontology of Illinois and other
Western States. In Proc. Acad. Nat. Sci. Phila. Vol. X,
2d ser. pp. 251-275, 1866.

17. A. H. WORTHEN; F. B. MEEK and.

Descriptions of Palaeozoic fossils from the Silurian, Devo-
nian and Carboniferous Rocks of Illinois and other Wes-
tern States. In Proc. Chicago Acad. Sci. pp. 11-23, 1866.

18. Geological Survey of Illinois, A. H. WORTHEN, Director,

Vol. I, Geology, pp. i-xvi and 1-504, plates I-VIII (dia-
grams and maps). Imp. 8vo. Chicago, 1866.

CONTENTS.

PAGES.

Letter to the Hon. Richard J. Oglesby i-vii

Introduction ix-xvi

CHAPTER I.

Physical Features, General Principles and Surface Geology,
A. H. WORTHEN 1-39

CHAPTER II.

Stratigraphical Geology, Tertiary Deposits and Coal Meas-
ures, A. H. WORTHEN 40-76

CHAPTER III.
Sub-Carboniferous Limestone Series, A. H. WORTHEN 77-118

CHAPTER IV.
Devonian and Silurian Systems, A. H. WORTHEN 119-152

CHAPTER V.
Geology of the Lead Region, PROF. J. D. WHITNEY 153-207

CHAPTER VI.
Report on the Coal Fields of Illinois, LEO LESQUEREUX.. 208-237

23

CHAPTER VII.

On the Origin and Formation of the Prairies, LEO LES-
QUEREUX 238-254

CHAPTER VIII.

Chemical Report for the Geological Survey of Illinois, DR.
J. V. Z. BLANEY 255-277

CHAPTER IX.
Geology of Randolph County, A. H. WORTHEN 278-296

CHAPTER X.
Geology of St. Clair County, A. H. WORTHEN 297-312

CHAPTER XI.
Geology of Madison County, A. H. WORTHEN 313-326

CHAPTER XII.
Geology of Hancock County, A. H. WORTHEN 327-349

CHAPTER XIII.

Geology of Hardin County. A. H. WORTHEN and HENRY
ENGELMANN 350-375

CHAPTER XIY.
Geology of Johnson County, HENRY ENGELMANN 376-409

CHAPTER XV.
Geology of Pulaski County, HENRY ENGELMANN 410-427

CHAPTER XVI.

Geology of Massac County, and that part of Pope County
south of Big Bay River. HENRY ENGELMANN 428-455

CHAPTER XVII.

Geology of Pope County. North of- Big Bay River. HENRY

ENGLEMANN 456-495

Glossary of Scientific Terms 497-504

24

19. Geological Survey of Illinois, A. H. WORTHEN, Director,
Vol. II, Palaeontology, pp. i-xix and 1-470, plates I-L,
Imp. 8vo. Chicago, 1866.

CONTENTS.

PAGES.

Introduction iii-xix

SECTION I.

Descriptions of new species of Vertebrates, mainly from
the Subcarboniferous limestones and Coal Measures, J.
S. NEWBERRY and A. H. WORTHEN 9-134

Remarks on the Occurrence of Fossil Fishes in Illinois, A.
. H. WORTHEN 11-16

Supplement to descriptions of Vertebrates, consisting of a
description of a new genus and species of Reptiles, from
the Coal Measures, PROF. EDW. D. COPE 135-142

SECTION II.

Descriptions of Invertebrates from the Carboniferous sys-
tem, F. B. MEEK and A. H. WORTHEN 143-411

Supplement to the descriptions of Invertebrates, consist-
ing of descriptions of Poylzoa from the Palaeozoic rocks,
H. A. PROUT ! 412-423

SECTION III.
Report on the Fossil Plants of Illinois, LEO LESQUEREUX.425-470

20. A. H. WORTHEN; F. B. MEEK and

Preliminary notice of a Scorpion, a Eurypterus? and
other fossils from the Coal Measures of Illinois. In Am.
Jour. Sci. Vol. XLV, 2d ser., pp. 19-28, 1868.

21. A. H. WORTHEN; F. B. MEEK and

Notes on some points in the structure and habits of the
Palaeozoic Crinoidea. In Proc. Acad. Nat. Sci. Phila., Vol.
XX, 2d ser., pp. 323-334, 1868.

22. A. H. WORTHEN: F. B. MEEK and

Remarks on some types of Carboniferous Crinoidea, with
descriptions of new genera and species of the same, and
of one Echinoid. In Proc. Acad. Nat. Sci. Phila., Vol.
XII, 2d ser., pp. 335-359, 1868.

23. Geological Survey of Illinois, A. H. WORTHEN, Director,

Vol. Ill, Geology and Palaeontology-, pp. i-vii and 1-574,
plates I-XX A.-H., and one map. Imp. 8vo. Chicago, 1868.

CONTEXTS.
PART I.

PAGES.

Letter to the Hon. Richard J. Oglesby vii

CHAPTER I.

Coal Measures and Lower Carboniferous Limestones, A. H.
WORTHEN 3-19

CHAPTER II.
Aeology of Alexander County, A. H. WORTHEN 20-32

CHAPTER III.
Geology of Union County, A. H. WORTHEN 33-57

CHAPTER IV.
Geology of Jackson County, A. H. WORTHEN 58-83

CHAPTER V.
Geology of Perry County, A. H. WORTHEN 84-103

CHAPTER VI.
Geology of Jersey County. A. H. WORTHEN 104-121

CHAPTER VII.
Geology of Greene County, A. H. WORTHEN 122-133

CHAPTER VIII.

Geology of Scott County, A. H. WORTHEN 134-144

-4

26

CHAPTER IX.
Geology of Washington County, HENRY ENGELMANN 145-171

CHAPTER X.
Geology of Clinton County, HENRY ENGELMANN 172-191

CHAPTER XI.
Geology of Marion County, HENRY ENGELMANN 192-218

CHAPTER XII.
Geology of Jefferson County, HENRY ENGELMANN 219-238

CHAPTER XIII.
Geology of Cook County, H. M. BANNISTER 239-256

CHAPTER XIV.
Geology of LaSalle County, H. C. FREEMAN 257-287

PART II.

Palaeontology of Illinois, F. B. MEEK and A. H. WOR-
THEN 289-565

Supplementary paper on the Fossil Insects of Illinois, S.
H. SCUDDER 566-572

Appendix— Chemical Analyses, J. V. Z. BLANEY 573-574

24. A. H. WORTHEN; F. B. MEEK and

Notes on some points in the structure and habits of the
Palaeozoic Crinoidea. In Am. Jour. Sci., Vol. XLVIII, 2d
ser., pp. 23-40, 1869. (Previously published in Proc.
Acad. Nat. Sci. Phila., pp. 323-334, 1868.

25. A. H. WORTHEN; F. B. MEEK and

Descriptions of new Crinoidea and Echinoidea from the
Carboniferous rocks of the Western States, with a note
on the genus Onychaster. In Proc. Acad. Nat. Sci. Phila.,
Vol. XXX, 2d ser., pp. 67-83, 1869.

27

26. A. H. WORTHEX: F. B. MEEK and

Remarks on the Blastoidea, with descriptions of new
species. In Proc. Acad. Nat. Sci. Phila., Vol. XIII, 2d
ser., pp. 83-91, 1869.

27. A. H. WORTHEN; F. B. MEEK and

Note on the relations of Synocladia. King, 1849, to the
proposed genus Septopora, Prout, 1858. In Proc. Acad.
Nat. Sci. Phila., Vol. XIV, 2d ser., pp. 15-18, 1870.

28. A. H. WORTHEN: F. B. MEEK and

Descriptions of new species and genera of fossils from the
Paleozoic rocks of the Western States. In Proc. Acad.
Xat. Sci. Phila., Vol. XIV, 2d ser., pp. 22-56, 1870.

29. Geological Survey of Illinois, A. H. WORTHEN, Director,

Vol. IV. Geology and Palaeontology, pp. i-vii and 1-508,
plates G, H, and I-XXXI, Imp. 8vo., Chicago, 1870.

CONTEXTS.

PART I.
Letter to the Hon. John M. Palmer vii

CHAPTER I.
Geology of Calhoun County, A. H. WORTHEX 24-42

CHAPTER II.
Geology of Pike County, A. H. WORTHEX 43-61

CHAPTER III.
Geology of Adams County, A. H. WORTHEX 43-61

CHAPTER IV.
Geology of Brown County. A. H. WORTHEX 62-74

CHAPTER V.
Geology of Schuyler County. A. H. WORTHEX 75-89

CHAPTER VI.
Geology of Fulton County, A. H. WORTHEN 90-110

28

CHAPTER VII.

Geology of DeKalb, Kane and DuPage Counties, H. M.
BANNISTER 111-125

CHAPTER VIII.

Geology of McHenry and Lake Counties, H. M. BANNIS-
TER..^ 126-135

CHAPTER IX.
Geology of Kendall County, HENRY M. BANNISTER 136-148

CHAPTER X.
Geology of Morgan County, HENRY M. BANNISTER 149-162

CHAPTER XI.
Geology of Cass and Menard Counties, H. M. BANNISTER.. 163-175

CHAPTER XII.

Geology of Tazewell, McLean, Logan and Mason Coun-
ties, H. M. BANNISTER 176-189

CHAPTER XIII.
Geology of Grundy County, FRANK H. BRADLEY 190-206

CHAPTER XIV.
Geology of Will County, FRANK H. BRADLEY 207-225

CHAPTER XV.

Geology of Kankakee and Iroquois Counties, F. H. BRAD-
LEY 226-240

CHAPTER XVI.
Geology of Vermilion County, FRANK H. BRADLEY 241-265

CHAPTER XVII.

Geology of Champaign, Edgar and Ford Counties, F. H.
BRADLEY... ...266-275

29

CHAPTEE XVIII.
Geology of Henderson County, H. A. GREEN 276-287

CHAPTER XIX.
Geology of Warren County, H. A. GREEN 288-300

CHAPTER XX.
Geology of Mercer County, H. A. GREEN 301-312

CHAPTER XXI.
Geology of Knox County, H. A. GREEN... 313-324

CHAPTER XXII.
Geology of Stark County, H. A. GREEN 325-333

CHAPTER XXIII.
Geology of Woodford County, H. A. GREEN 334-342

PART II — PALAEONTOLOGY OF ILLINOIS.

SECTION I.

Descriptions of Vertebrates, J. S. NEWBERRY and A. H.
WORTHEX 346-374

SECTION II.
Descriptions of Plants, LEO LESQUEREUX 377-508

30. A. H. WORTHEN.

Remarks on the Relative Age of the Niagara and the so-
called Lower Helderberg Groups. Proc. Am. Assoc. Adv.
Sci., 19th Meeting, Troy, N. Y., pp. 172-175, Cambridge,
1871.

31. Geological Survey of Illinois, A. H. WORTHEN, Director,

Vol. V, Geology and Paleontology, pp. i-iii and 1-619,
Plates H, and I-XXX1I, Imp. 8vo., Chicago, 1873.

CONTENTS.

PART I.
Letter to the Hon. John L. Beveridge iii

30

CHAPTER I.
Geology of Northwestern Illinois, JAMES SHAW 1-24

CHAPTER II.
Geology of JoDaviess County, JAMES SHAW 25-56

CHAPTER III.
Geology of Stephenson County, JAMES SHAW 57-74

CHAPTER IV.
Geology of Carroll County, JAMES SHAW 75-81

CHAPTER V.
Geology of Winnebago County, JAMES SHAW 82-94

CHAPTER VI.
Geology of Boone County, JAMES SHAW 95-103

CHAPTER VII.
Geology of Ogle County, JAMES SHAW 104-123

CHAPTER VIII.
Geology of Lee County, JAMES SHAW 124-139

CHAPTER IX.
Geology of Whiteside County, JAMES SHAW 140-166

CHAPTER X.
Geology of Bureau County, JAMES SHAW 167-184

CHAPTER XI.
Geology of Henry County, JAMES SHAW 185-201

CAAPTER XII.

Geology of Marshall and Putnam Counties, JAMES SHAW.. 202-216

CHAPTER XIII.

Geology of Rock Island County, A. H. WORTHEN and
JAMES SHAW... ...217-234

31

CHAPTER XIV.
Geology of Peoria County, A. H. WORTHEX 235-252

CHAPTER XT.
Geology of McDonough County, A. H. WORTHEX 253-265

CHAPTER XVI.
Geology of Monroe County, A. H. WORTHEX 266-285

CHAPTER XVII.
Geology of Macoupin County, A. H. WORTHEX 286-305

CHAPTER XVIII.
Geology of Sangamon County. A. H. WORTHEX 306-319

PART II.

Palaeontology of Illinois, F. B. MEEK and A. H. WOR-
THEX 323-619

32. Geological Survey of Illinois, A. H. WORTHEX, Director,
Vol. VI, Geology and Palaeontology, pp. i-iii and 1-532,
plates I-XXXIII, Imp. 8vo., Chicago, 1875.

CONTEXTS.
Letter to the Hon. John L. Beveridge iii

PART I.

CHAPTER I.
Coal Measures, A. H. WORTHEX 1-8

CHAPTER II.
Geology of Clark County. A. H. WORTHEX 9-21

CHAPTER III.

Geology of Crawford and Jasper Counties, A. H. WOR-
THEX... ...22-36

32

CHAPTER IV.

Geology of Lawrence and Richland Counties, A. H. WOR-
THEN 37-50

CHAPTER V.

Geology of Wabash and Hamilton Counties, A. H. WOR-
THEN 51-65

CHAPTER VI.

Geology of White and Hamilton Counties, A. H. WOR-
THEN 66-81

CHAPTER VII.
Geology of Wayne and Clay Counties, A. H. WORTHEN... ..82-97

CHAPTER VIII.

Geology of Cumberland, Coles and Douglass Counties, A.
H. WORTHEN 98-111

CHAPTER IX.

Geology of Williamson and Franklin Counties, A. H.
WORTHEN 112-127

CHAPTER X.
Geology of Bond County. G. C. BROADHEAD 128-134

CHAPTER XI.
Geology of Fayette County, G. C. BROADHEAD 135-148

CHAPTER XII.

/"

Geology of Montgomery County, G. C. BROADHEAD 149-155

CHAPTER XIII.
Geology of Christian County, G. C. BROADHEAD 156-162

CHAPTER XIV.
Geology of Shelby County, G. C. BROADHEAD 163-174

CHAPTER XV.
Geology of Effingham County, G. C. BROADHEAD 175-184

33

CHAPTER XVI.

Geology of Moultrie, Macon and Piatt Counties, G. C.
BROADHEAD 185-196

CHAPTER XVII.
Geology of Gallatin County, E. T. Cox 197-219

CHAPTER XVIII.
Geology of Saline County, E. T. Cox 220-234

CHAPTER XIX.
Geology of Livingston County, H. C. FREEMAN 235-244

PART II.

SECTION I.

Descriptions of Vertebrates, ORESTES ST. JOHN and A. H.
WORTHEX 245-488

SECTION II.

Descriptions of Invertebrates, A. H. WORTHEN and E. B.
MEEK 489-532

Geological Map of the State of Illinois from Original Surveys,
made under the direction of A. H. WORTHEN, State Geologist.

33. A. H. WORTHEX.

Descriptions of fifty-four new species of Crinoids from the
Lower Carboniferous Limestones and Coal Measures of
Illinois and Iowa. In Bulletin No. I, Illinois State Museum
of Natural History., pp. 3-38, 1882.

34. A. H. WORTHEN.

Corrections and proposed new names for species previously
described in Geological Survey of Illinois under names that
were pre-occupied ; and descriptions of two new species of
fossil shells from the Coal Measures of Illinois and Kansas.
In Bull. Xo. I, Illinois State Museum of Xatural History,
pp. 38-40.
— 5

34

35. A. H. WORTHEN.

Economic Geology of Illinois. Reprinted from the original
reports of the Geological Survey with additions and
amendations. Published by authority of the Legislature
of Illinois, Springfield, 1882. Vol. I, pp. 541, Vol. II, pp.
615, Vol. Ill, pp. 596.

36. Geological Survey of Illinois, A. H. WORTHEN, Director,

Vol. VII, Geology and Palaeontology, pp. i-iv and 1-373,
plates I-XXXI, Imp. 8vo. Chicago, 1883.

CONTENTS.

CHAPTER I.
Economical Geology, A. H. WORTHEN 1-51

PART II.

Palaeontology of Illinois, Section I, Fossil Fishes, ORESTES
ST. JOHN and A. H. WORTHEN 52-264

Palaeontology of Illinois. Section II. Description of Fossil
Invertebrates.

Descriptions of Lower Carboniferous and Coal Measure In-
vertebrates, most of which were originally described in
Bull. No. I, 111. State Mus. Nat. Hist., A. H. WORTHEN.. 265-322

Descriptions of some new species of Fossil Shells from the
Lower Carboniferous Limestones and Coal Measures of
Illinois, A. H. WORTHEN 323-326

Descriptions of new Carboniferous Echinoderins, A. H.
WORTHEN and S. A. MILLER : 327-338

Palaeontology of Illinois. Section III. Descriptions of
, Fossil Invertebrates, CHARLES WACHSMUTH and W. H.
BARRIS 339-364

37. A. H. WORTHEN.

Bulletin No. 2 of the Illinois State Museum of Natural
History. Descriptions of two new species of Crustacea,
fifty-one species of Mollusca, and three species of Crinoids,
from the Carboniferous formation of Illinois and adjacent
States, pp. 27, Imp. 8vo. Springfield, March, 1884.

35

38. Geological Survey of Illinois; A. H. WORTHEN, Director, Vol.
Till, Geology and Palaeontology, pp. i-xi and 1-728
Plates I-LXXVIII. Posthumous publication, edited by
JOSUA LINDAHL. With an appendix, pp. 1-151, and map.
Imp. 8vo. Springfield, 1890.

CONTEXTS.

Table of Contents iii-iv

Letter of Transmittal v-xi

PART I. GEOLOGY.

CHAPTER I.
Drift Deposits of Illinois, A. H. WORTHEN 1-24

CHAPTER II.

Economical Geology (Coal; Natural Gas and Oil; Artesian
Water), A. H. WORTHEN 25-67

PART II. PALEONTOLOGY.

SECTION I.
Description of Fossil Invertebrates, A. H. WORTHEN 69-154

SECTION II.

New species of Crinoids and Blastoids from the Kinder-
hook group of the Lower Carboniferous Rocks at Le-
Grand, Iowa; and A new genus from the Niagara group
of Western Tennessee, CHARLES WACHSMUTH and FRANK
SPRINGER 155-208

SECTION III.
American Palaeozoic Sponges, E. O. ULRICH 209-241

SECTION IV.

Sponges of the Devonian and Carboniferous Systems, E.
O. ULRICH... ...243-251

36

SECTION V.

Descriptions of Lower Silurian Sponges, E. O. ULRICH and
OLIVER EVERETT 253-282

SECTION VI.

Palaeozoic Bryozoa, E. 0. ULRICH , 283-678

Index to Part 1 689-691

Index to Part II, Sections I, II 693-699

Index to Part II, Sections III, IV and V... 701-706

Index to Part II, Section VI 707-727

Table of Contents to Part II, Section VI 728

Plates I-LXXVIII and explanations.

APPENDIX.

The Private Life and Scientific Works of PROF. AMOS HENRY
WOKTHEN, by N. W. Bliss and C. A. White, with a portrait
of Prof. Worthen, by Jacques Reich 3-37

General Index to Geological Survey of Illinois, A. H. WOR-
THEN, Director, Vols. I-VIII, by Josua Lindahl 39-151

Approximate Geological Map of Illinois.

The foregoing list comprises all the publications of Professor
Worthen that have come to the knowledge of the writer, and
it is believed to be nearly or quite complete. It is proper to
say that nearly or quite all the matter contained in the publi-
cations mentioned in that list, exclusive of the eight large vol-
umes of Survey reports, is also contained in those volumes in a
completed form. That is, those publications consist of material
which was printed in advance of the reports, or of tha.t which
has been abstracted from those volumes after their publication.

The eight large volumes and accompanying maps therefore
represent fairly the results of Professor Worthen 's life work.
It is impracticable to present an extended analysis of that
work on this occasion, but the following brief summary will
serve to give an indication of its magnitude.

This great work embraces the geology, both structural and
economic, and the palaeontology of Illinois. In the geological
division was accomplished the mapping, upon one comprehensive
sheet and various smaller ones, the nearly 56,000 square
miles which are embraced within the boundaries of that State,

37

in such a way as to show its geological structure and the area
occupied by each formation. The geological structure is further
shown by numerous measured sections, most of them showing
local relations of the strata, but the principal one was con-
structed from exposures along the Mississippi river, which forms
the whole western boundary of the State. This section shows
the relation of the different formations, from the Potsdam
Sandstone to the Coal Measures, inclusive, for a distance of
more than 600 miles.

The immense economic resources of the State are also shown
in these volumes. The characteristics and outlines of its 37,000
square miles of productive coal field are recorded. The lead
region has been carefully explored and mapped, and the char-
acter of its mineral products determined. Besides this the
character of the soils of the State is described; and its re-
sources in stone and other building material are shown to be
abundant and good.

The most conspicuous portion of this great work, however,
is its palaeontology. This portion is so extensive and elaborate
that the volumes of the Illinois survey have long been indis-
pensable to every palaeontologist in every part of the world
where the palaeozoic formations are studied. The fossil forms
described are all well illustrated. They have been collected from
all the formations, from the Potsdam Sandstone to the Upper
Coal Measures, inclusive: but those of the Lower Carboniferous
and the Coal Measures are especially abundant. Some indica-
tion of the extent of this palaeontological work is shown by the
fact that it embraces the description and illustration of 297
species of vertebrates, 1073 species of invertebrates and 256
species of plants. Nearly 1.500 of these species were first made
known to the scientific world through the publications enumer-
ated in the foregoing list.

Such briefly are the character and extent of the labors of
one who for nearly forty years devoted his best energies to
their fulfillment.

GEOLOGICAL SURVEY OF ILLINOIS.

A. H. WORTHEN, DIRECTOR.

GENERAL INDEX

TO

VOLUMES I-VIIL

BY

DR. JOSUA LLXDAHL.
1890.

A. GEOLOGY, with List of Illustrations.

B. PALEONTOLOGY:

I. SYNOPTIC TABLE.
II. PLANTS,
III. ANIMALS,
APPROXIMATE GEOLOGICAL MAP OF ILLINOIS.

GENERAL INDEX TO GEOLOGICAL SURVEY
OF ILLINOIS.

VOLUMES I— VIII.
A. GEOLOGY.

Alluvial deposits 1,24; V111.7

Altitudes in niinoi - 1, 3

Grundy Co FV, 192

Will Co IV.224

Ancient soils in the Drift IV, 45; V, 307; Vn,23; VIII, 9, 14, 15, 16. 18

valleys 1,7; IV, 191, 237; VHI,11.28,34

Anticlinal axis 1,5,7; V.39,41; Vn,39; Vm.25

Antiquities — see Indian remain-.

Ai chimedes limestone n,13

Area of Illinois 1, 2

Artesian wells in Bureau Co V,172,173

Cass Co Vm, 65

Cook Co EH, 244

Fulton Co Vn,5; Yin. 62

Grundy Co IV,205

Hancock Co V ill, 62, 64, 65

Kane Co IV. 114

LaSalle Co VII, 40, 49,50

Livingston Co VI, 244

Morgan Co VHI,66

Eichland Co Vn,5,7.40: VIII,63

Tazewell Co IV. 189

Warren Co Vm,62,66

Athens (Lockport) Marble 1,133; IV.220

Azoic rocks 1, 19

Barren coal measures 1,48

Barrens and postoak flats HI, 84-87

Bitumen in Cook Co 111,255

Bituminous shales 1, 140, 176,262; V.16

Black slate 1, 119

Blue and Buff limestone 1,165. V.21,22

Boulder Clays— see Quaternary deposits.

Building stone VH.34

" , Table showing tests and properties of V.157

Burlington group 1, 102-108 ; VIH, 159

Burrstone 1, 234

Calciferous sandstone 1,149,163; 111,280-282

Calif ornia diggings 1, 142

—6

I

I

I

42 GENERAL INDEX.

Carboniferous system 1,40-118; 111,1-19; VH.58

Cement 1,324; IV, 40: VII.39

CHEMICAL ANALYSES of:—

Bituminous shales in Carroll Co. (Cincinnati) 1,140,176

Building materials in Adams County, White limestone (Burlington) 1,107

Brown " 1,108

Alexander Co., Cape Girardeau Marble (Trenton) 1, 148

" " Cook Co., Hydraulic limestone (Niagara) Ill, 574

Greene Co., Hydraulic limestone (St. Louis) 111,573

" Hancock Co., Hydraulic limestone (St. Louis) 1,339

(Keokuk) 1,99

Hardin Co., Oolitic limestone (St. Louis) 1,374

Jackson Co., Limestone (Oriskany) 111,574

Jersey Co., Buff Dolomite (Niagara) 1,136; 111,117

" " " Hydraulic limestone (Hami 'ton).. 111,574

•• " Kane Co., Hydraulic limestone (Niagara) 111,573

" LaSalle Co., Hydraulic limestone (L. Magnesian) 1,151,256

" " Pike Co., Hydraulic limestone (Kinderhook) IV, 40

" " " Brown Dolomite (Niagara) 1,135

" " Sangamon Co., Limestone (Coal measures) 1,61

Union Co., Hydraulic limestone 1,255,256

- " Will Co., Joliet limestone (Niagara) 1,133

Building stones in Iowa, concretionary limestone (Niagara) 1,134

Coal in Adams Co., Coatsburg 1,275

McDonalds Creek IV.50

Mendon IV.58

" Bureau Co., Sheffield 1,276: V.176

Tiskilwa V.179

Calhoun Co., Fruitland Landing IV, 21

Fulton Co., Canton and Cuba 1.275: IV.104

" Grundy Co., Morris 1,277

Henry Co., Kewanee V.197

Bock River V.191

" Jackson Co., Murphysborough 111,77

Knox Co., Bursans Mine 1,276

" Kane Co., Briar Hill 1,267

MaQUon 1,276

Oneida 1,276 [IV, 316]

Sinn's Mine 1,276

" LaSalle Co., LaSalle 1,276

Little Vermilion 1,276

N. IlJinois Coal Co's Mine 1,276

Peru 1,276

Macotfcin Co., Hodges Creek V.302

Madison Co., Alton 1,319

Marion Co., Kinmundy VIII,42,691

Marshall Co., Lacon Station 1,276

" McDonough Co., Colchester IV.105; [V.262]

Mercer Co., various mines 1, 276

Peoria Co., various mines 1,276; [V.248]

Perry Co. DuQuoin 111,98

" Pike Co., Pittsfleld IV.33

" Randolph Co., various mines 1,276; 111,574

" Rock Island Co., Carbon Cliff V,221

Schuyler Co., Pleasant View IV.85

Rushville... IV.86

GENERAL INDEX. 43

CHEMICAL ANALYSES of:—

Coal in Scott Co., various mines 111,141.142

St. Clair Co., various mines 1,308,309

Vermilion Co., Danville 17,257

Grape Creek IV, 259

Warren Co., Avon 1,276

Spring Grove 1.276

Coal from Scotland and from Kentucky (for oil) 1,272

Fire-clay in Adams Co., Coatsburg ; 1.275

from England used for glass-melting pots 1,275

Fuels, different kinds 1,260

Ores, iron, in Hardin Co.. pipe ore 1,256

limonite 1. 257

Schuyler Co., Argillaceous carbonate 1.275: HV.87J

from Pennsylvania, Argillaceous carbonate 1.275; UV,87]

Ores, lead, in Hardin Co., Galena with gold and silver in. 18

from 111. and Wis., Galena with silver 1.188

Water, brine, in Gallatin Co., Saline VT.216

chalybeate in Hamilton Co.. McLeansboro VI.80

Schuyler Co IV, 89

alkaline in Brown Co., Versailles IV, 74

Pike Co., Perry Springs IV.41

Chemical analysis of soil, importance of 1,257

Chemung group , n, x

Chester group 1, 41, 77-83; VH. 34

Cincinnati group 1.136-141.172; ll.xviii; 111,324; Vn,58

Clay 1,24,48,275; VH.40

Clear Creek limestone 1,126-129; H.x

Climate of Illinois 1,2

Coal, amount produced from a given thickness 1,65

' analysis of— see Chemical analyses.

' ' anthracite 1,65

" beds, dip of 111,16

' ' cannel 1, 64.262

' ' classification of 1,261

" how formed 1,68,209

" production in Illinois in 1867 III. 16; V.7

1880 V.7

Coal fields of Illinois, report by LEO LESQUEBEUX 1,208-237

Coal measures, reports by A. H. WOBTHKN ..1,49-76; 111,1-17; VI.1-8; VH.1-34; Vm.25-54

general sections of, in Illinois 1,234; VI,3; Vn,2

Coal oil 1,72,268-272; VTI,37

Coke and Coking 1.70,268-272

Concretions IV, 18

Cone in cone, or Tuten mergel VI. 128,131

Conglomerate 1,48,82; m,l,9.68

Copper in the drift, native V.101; VHI.19

Coralline beds 1, 177

Cornif erous group 1,120; in, 407

COUNTIES,* geological reports on Vols. I, III- VII

* The items of each county report are not arranged alphabetically in this index, but
generally in the following order: Physical features, Sections of Strata. Stratigraphical
Geology (in chronological order). Economical Geology, Indian antiquities.

44 GENERAL INDEX.

Adams Co., (A. H. WOBTHEN) IV.43-61

Physical features IV.43

" Section of strata IV, 44

Quaternary deposits 1V.46; VIII,8,15

" Coal measures IV, 48

St. Louis group IV, 51

Keokuk group IV, 53

Burlington group IV,55

Kinderhook group IV, 57

Economical Geology, (coal, building stone, limestone for lime, fire
and potter's clay, clay and sand for brick, soil and timber) IV, 58

Alexander Co., (A. H. WOBTHEN and H. ENGELMANN) 111,20-32

Physical features 111,20

Section of strata Ill, 21

Tertiary System 111,21

" Black Slate, Hainilton.and Corniferous gr 111,22

' ' Onondaga group Ill, 23

" Clear Creek Limestone 111,24

" Lower Helderberg Limestone 111,25

Cincinnati group 111,26

Thebes Sandstone and Shale 1,139; 111,27

• ' Trenton Limestone 111,28

" Economical Geology (lead and iron ores, building stone and

marble, clay and sand, road material, agriculture) 111,19

Bond Co.. (G. C. BBOADHEAD) VI.128-134

" Physical features, timber and soil VI, 129

Sections of strata VI, 128-133

" Quaternary deposits VI, 130

Coal Measures VII, 131

" Economical Geology, (coal, building material, fire clay, water, soil

and agriculture) VI, 134

Boone Co., (JAMES SHAW) V.95-103

Physical features V, 95

" Section of strata V,97

" Quaternary deposits V,97

Cincinnati shales V,98

Galena limestone V,99

Blue limestone V, 100

Economical Geology, (building stone, lime, bog-iron ore, copper in

the drift, chalybeate springs, sand and clay, peat, agriculture) — V.100
Indian relics V.102

Brown Co.. (A. H. WOBTHEN) IV.62-74

Physical features IV, 62

Sections of strata r. IV, 63, 65, 70

' ' Quaternary deposits IV, 63

' ' Coal measures IV, 65

St. Louis group IV, 68

Keokuk group IV.69

Economical Geology, (potter's clay, fire clay, building stone, limestone
for lime, sand and clay for brick, soil and agriculture, mineral
springs and analyses) IV.70

Bureau Co., (JAMES SHAW) V, 167-184

. ' ' Physical features V, 167

" Sections of strata V.169-180

Quaternary deposits V.170

" Coal measures V.172

GENERAL INDEX. 45

Bureau Co..(Cincinna?i and Trenton) V.181

Economical Geology, (coal, building stone, clays, sand, peat, agricul-
ture) V.182

Calhoun Co., (A. H. WOBTHEN IV.1-23

Physical features IV.l

Fault at Cap au Gres -. IY.2t

'Sections of strata 1,111 IV,3,4,13,16

St. Peter sandstone IV H

Trenton group FV,4

Cincinnati group IV.5

Niagara limestone IV,6

Hamilton limestone IV.8

Kinderhook group IV. 9

Burlington limestone IV,12

Keokuk limestone IV, 14

St. Louis group IY.15

Coal Measures IV, 15,21

Quaternary system, drift, loess IV.17

Economical Geology, (building stone, limestone for lime, glass sand,

iron ore, mineral springs, agriculture and soil) IV.18

Carroll Co., (JAMES SHAW) V.75-81

Physical features V,75

Galena limestone 1,142 ; V, 76

Cincinnati group V,77

Niagara C'Pentamerus beds") V,78

Quaternary system V.79; VHI.IO

Cass and Menard Counties, (H. M. BANNISTEB) IT, 1' 3-175

Physical features IV.163

Sections of strata IV,164-173; VH.14- 2: Vin,16,61

Quaternary IV, 164 ; VTTT, 8, 16

Coal measures IV.165; VII.42

Economical Geology, (coal, iron ore, building stone, other building
materials) IV, 173; VII, 14

Champaign, Edgar and Ford Counties (FBANK H. BBADLEY) IT, 266-275

Section of strata IV, 276, 270, 272; VHI,17,27

Quaternary deposits IV, 266, 272, 273: VUUL, 12,28

Coal measures IV, 267, 271 ; VIII, 26

Ancient channel from Lake Michigan IY.273 ; VLU, 12

Christian Co., (G. C. BBOADHEAD) YI.156-162

General features, soil, timber, crops, etc VI, 156

Sections of strata VI.128, ;59-161; VEI,22; Vm,15,16

Quaternary VI, 158

Coal measures VI, 159

Economical geology, (coal, building material) VI, 162

Clark Co., (A. H. WOBTHEN) VI.9-21

Sections VI.10-19

Quaternary deposits VI, 10

Coal measures VI, 10

Economical geology, (coal, building stone, lime, potter's clay, soil
timber) VI, 20

Clay Co.— See "Wayne and Clay counties.

Clinton Co., (H. ENGELMAX) 111,172-191

Physical feature - Ill, 172

46 GENERAL INDEX.

Clinton Co., Sections of strata 1,223, 111,178

Upper Coal measures (Upper Sandstone, Shoal Creek limestone,

Slaty division. Lower sandstone) 111,174

Lower Coal Measures 111,174; VII, 9,10

Economical geology, (coal, iron ores, building material agriculture) . . Ill, 186

Coles Co.— See Cumberland, Coles and Douglas Counties.

Cook Co.,(H. M. BANNISTEE) m,239-256

Physical features III. 239

Sections of strata 111,241,244

Quaternary deposits 111,240

Niagara group 111,245

Artesian boring (Niagara— Lower Magnes ian) Ill, 244

'Economical Geology, (building stone, lime and cement, clay, sand,
peat, bitumens, minerals in the drift, soil) 111,253

Crawford Co., (A. H. WOBTHEN) TI.22-30

Physical features V.22

Sections of strata. VI.23-28

Quaternary deposits VI.22

Coal measures VI, 23

Economical Geology, (building stone, lime, iron ore, sand, gravel,

clay, soil, timber) VI.29

Indian mounds VI, 90

Cumberland, Coles and Douglas Counties. (A. H. WOBTHEN) VI.98-111

Physical features VI.98,104,110

Sections of strata VI.99-109; VIII,17,26

' ' Upper Coal measures (no coal seams) VI.98, 105, 110

" Economical Geology, (building stone, lime, iron ore, sand, clay, soil,

timber) VI.103, 109

DeKalb.Kane and DuPage Counties (H. M. BANNISTEB) IV, 111-125

' ' Physical features IV, 111

Sections of strata IV.114,138

' ' Quaternary system IV.112

Niagara group IV.114

Cincinnati group IV, 121

' ' Trenton group IV.122

' ' Economical Geology, (building stone, limestone for lime, other build-
ing material, peat, agriculture, etc) IV, 125

DeWitt Co., (No general report.)

sections at Clinton and Farmer City VII. 16: VIII.13,34.35,58

Douglas Co.— See Cumberland, Coles and Douglas Counties.

DuPage Co.— See DeKalb, Kane and DuPage Counties.

Edgar Co.— See Champaign, Edgar and Tord Counties.

Edwards Co.— See Wabash and Edwards Counties.

Efflngham Co., (G. C. BBOADHEAD) VI.175-184

Physical features VI, 175

Sections of Strata VI.176-181; VH.33; VIII.55

Quaternary deposits VI, 176

' ' Coal measures VI, 177

Economical Geology, (coal, iron ore, building rock, potter's clay,
water, soil, "scalds") VI.182

Fayette Co., (G. C. BBOADHEAD and A. H. WOBTHEN) VI, 135-148

Physical features VI , 135

Sections of strata... VI. 128, 137-142, 147

GENERAL INDEX. 47

Fayerte Co.. Quaternary deposits VI, 137

Coal measures .- VI, 139,147

Economical Geology, (coal, building rock, road material, agricul-
ture, water) VI. 143

Indian relics VI, 146

Ford Co.— See Champaign Edgar and Ford Counties.
Franklin Co.— See Williamson and Franklin Counties.

Fulton Co., (A. H. WOBTHEN) IV,90-110

Physical features IY.90

Sections of strata IV. 93-103 ; VH, 3-6; VIII. 68

Quaternary deposits IV, 91

Coal measures IV, 92; VII.3-6

St. Louis limestone IV, 103

Economical Geology, (coal, fire clay, iron ore. building stone, lime-
stone for lime, sand and clay for brick, agriculture).. IV, 103; VII, 3-6, 36
List of trees and shrubs in Fulton County IV, 109

Gal'atin Co.. (E. T. Cox) VI, 197-219

Physical features VI. 197

Sections of strata 1.213; VI, 4, 198t, 200-212

Quaternary deposits VI, 213, 214

Coal measures :1.213; VI.2"2; VH.4,7; Vm,54

Chester group VI.200

Economical Geology, (coal, brine springs, clay, iron-stone, building

stone auicklime, potter's clay, agriculture) VI, 213

Indian relics VI, 216

Greene Co.. (A. H. WOBTHEN) m,122-133

Physical features HI, 122

Sections of strata m, 123-126; YH, 3, 12

Quaternary deposits rn,123

Coal measures HI.124

St. Louis limestone 111,127

Keokuk limestone m, 128

Burlington limestone m, 129

Kinderhook group m, 130

Economical Geology, (coal, clays, hydraulic limestone, iron ore, lime-
stone for lime, building stone, agriculture) in, 130

Grundy Co.. (FBANK H. BBADLET) IY.190-206

Physical features, elevations, etc IV, 190,192

Sections of strata IV, 195

Quaternary deposits IV, 191

Coal measures 1,55; IV.194

Cincinnati group IV,200

Trenton limestone IV.201

St Peter sandstone IV.201

Economical Geology, (coal, brick, potters' clay, building stone, lime,
hydraulic lime, sand and gravel, iron ore, water, gas.) IV, 202

Hamilton Co.— See White and Hamilton Counties.

Hancock Co.. (A. H. WOBTHKK) 1,327-349

Physical features 1,327

Sections of strata 1,25,86,329-338; Vm,7,65

Quaternary deposits 1,25

Cretaceous fossils in the drift VIII, 5

Coal measures 1,86,330

48 GENERAL INDEX.

Hancock Co., St. Louis limestone 1,84,333

Keokuk limestone 1,89-102,334

Geodes from the Keokuk limestone, a report by GEO. J. BBUSH,..I,90-%
Economical Goology, (building stone, hydraulic limestone, potter's

clay, coal, agriculture) 1,338

Statistics on vine and fruit in Hancock county, by N. W. BLISS.. 1, 341-349

Hardin Co., (A. H. WOETHEN and H. ENGELMAN> ) 1,350-375

Physical features 1,350

Map of Hardin Co opp. 1,350

Sections of strata 1,356

Coal measures (millstone grit, conglomerate sandstone) 1,351,359

Chester group 1,350

St. Louis group (including the lead bearing strata)... 1, 87, 350, 353; 111,17-19

Keokuk group 1,350,353

Kinderhook group 1,352

Black slate (Devonian) 1,352

Keport on the Eosiclare Lead Mines, with 4 maps and plans, by

Dr. J. G. NORWOOD 1,366-372

Economical Geology, (coal, iron ores, galena, zinc blende, fluor spar,

mineral springs, building material, agriculture) 1,362,372; 111,17-19

Henderson Co., (H. A. GBEENE) .IV.276-287

Physical features IV, 276

Sections of Strata IV.279-285

" Quarternary deposits IV, 277

" Coal measures IV.278

St. Louis group IV, 278

Keokuk group IV.279

Burlington group IV,281

Kinderhook group IV.285

" Economical Geology, (building stone, limestone for lime, coal, clay,

zinc blende, agriculture) IV, 286

Henry Co., (JAMES SHAW and A. H. WOETHEN) V, 185.201

Physical features V.184

Sections of strata V.187-199

Quarternary deposits V.187

Coal measures (lower) V.188; VII, 4

' ' Devonian limestone (Hamilton) V.187

' ' Niagara limestone (LeClair) V, 187

Economical Geology, (coal, stone, clays, agriculture) V.200

Iroquois Co., (see Kankakee and Iroquois counties.)

Jackson Co., (A. H. WOETHEN and H. ENGELMANN) 111,58-83

Physical features, (with four steel engravings from sketches of "The
Devil's Bake-Oven" and "Back-Bone" (Devonian), by PAULUS

BOETTEB 111,58

Sections of strata 111,61-73; VIII, 52

Quarternary deposits 111,75

Lower Coal measures 111,69; VIII, 53

List of 66 localities of coal in the county 111,74

Conglomerate 111,68

Chester group 111,65

St. Louis and Keokuk groups III. 64

Hamil' on group 111,63

Oriskany group 111,62

Onondaga group 111,62

GENERAL INDEX. 49

Jackson Co., Lower Helderberg group 111,62

Economical Geology, (coal, building stone, iron ores, lead ore,
saltpetre, brine, sand and clays, agriculture) 111,76

Jasper Co.. (A. H. WOBTHES) VI, 31-36

Physical features VI,31

Sections of strata YI.33-35

Quarternary deposits VI, 31

Coal measures VI.31

Economical Geology, (coal, building stone, lime, sand and clay, soil
and timber) YI.35

Jefferson Co., (H. EXGELMAITN) m,219-238

Physical features 111,219

Coal measures m.220; Vm.56

. " Economical Geology, (coal, mineral springs, building material, agri-
culture) 111,235

Jersey Co., (A. H. WOBTHEN) IH,104-121

Physical features 111,104

Four steel engravings of landscapes in the county, showing outcrops
of Subcarboniferous and Niagara rocks— Opp. 111,59,61; IV.front-
ispiece; V, frontispiece.

Sections of strata m,105-109

' ' Quarternary deposits HI, 105

Coal measures HI, 107; VII, 12

St . Louis group HI, 11 1

Keokuk group HI, 112

" Burlington group m,113

Kinderhook group HI, 115

Black slate group HI, 115

Hamilton group HI, 116

Niagara group HI, 116

Cincinnati group Ht.117

Trenton group HI, 118

Economical Geology, (coal, clays, hydraulic limestone, lime, building
stone, soil, timber, etc.) HI.118

JoDaviess Co., (JAMES SHAW) , V.25-56

Physical features V. 25

Map of the Galena Lead Region opp. 1,154

Diagram of lead bearing crevices near Galena opp. 1,182

View of lead bearing rocks and furnace near Galena I, frontispiece

Sections of strata 1,141,16-2,174; V.38

Quaternary deposits V, 28

Niagara limestone V, 33

Cincinnati group V.35

Galena limestone V.36

Trenton limestone V.38

Economical Geology, (building stone, lime, clays and sand, min-
erals,) V.39

Lead mining 1,153-207; V.40-56

JOHNSON Co,, (H. EKGET.MAXX) 1,376-409

Physical features 1,376

Sections of strata 1,380-397: Vm,54

Tertiary ? sand 1, 409

Coal measures (Conglomerate beds) 1,397-404

Chester group 00 distinct divisions) 1,381-397

— 7

50 GENERAL INDEX.

Johnson Co., St. Louis group 1,378-381

Economical Geology, (coal, iron ore, saltpetre, mineral springs, build-
ing material, agriculture) 1,404,409

Kane Co.— See DeKalb, Kane and DuPage counties.

Kankakee and Iroquois Counties, (F. H. BB ADLEY) IV, 226- 240

Physical features IV, 226

Sections of strata IV, 231-237; VII.25

Quaternary (ancient channel of Lake Michigan) IV, 226-230 ; VIII, 11

Coal measures IV, 231

Niagara limestone I V , 232

Cincinnati group IV, 233

Economical Geology, (coal, bog-iron, peat, building stone, water) ..IV, 234

Kendall Co., (H. M. BANNISTER) IV, 136-148

Physical features IV, 136

Sections (vertical) of strata IV, 1 11-145

Longitudinal section from Montgomery, Kane Co., to Milford IV.138

Drift IV, 137

Coal measures IV, 138

Niagara group IV, 139

Cincinnati group IV, 140

Galena and Trenton limestones IV, 143

St. Peter's sandstone IV, 146

Economical Geology, (building materials, sulphur springs, peal) — IV, 147

Knox Co., (H. A. GBEEN) IV.313-324

Physical features IV, 313

Sections of strata IV, 314-322

Quaternary deposit- IV, 313

Coal measures I,22f»; IV, 314-322

Economical Geology, (building stone, lime, coal) IV, 322

Lake Co.— See McHenry and Lake Counties.

LaSalle Co., (LEO LESQUEREUX) 1,231-237

(C. H. FREEMAN) 111,257-287

(A. H. WORTHEN) VIM, 39-51

Geological map of the county (exc. Tps. 29 and 30, K. 2, E.) ....opp. 111,256

Physical features 111,256

Sections (vertical) 1,231; 111,263-286; VII, 41-51

Sections (longitudinal 111,261,270

Quaternary deposits 111,262; VII, 51

Coal measures 1,231 237; 111,264-275; VII, 40-50

Trenton limestone 111,276 ; VII, 40

St. Peter's sandstone 111,279; VII, 39

Calciferous 111,280; VII.50

Economical Geology, (coal, building stone, lime, glass, sand, hydraulic
cement, fire clay, peat, mineral springs, artesian wells, natural
gas) Ill, 282 ; VII , 39-51

Lawrence and Richland counties. (A. H. WORTHEN) VI, 37-50

Physical features VI, 37, 44

Sections of strata VI, 38-48; VII.8

Quaternary deposits VI, 37,44

Coal measures VI, 38, 45: VII, 8

Economical Geology, (coal, building stone, iron ore, lime, agricul-
ture) ...VI.42,48

GENERAL INDEX. 51

Lee Co., (JAMES SHAW) V.124-139

Physical features V, 124

Sections of strata. V.126

Quaternary deposits V.134: Vlil.ll

Niagara limestone V.132

Cincinnati group V.131

Galena limestone V, 129

Blue or old Trenton V.128

Buff limestone V.128

St Peter's sandstone V.126

Economical Geology, (building stone, lime, clays and sands, glass
sand, peat, agriculture V.134

Livingston Co.. (H. C. FBEEMAN) YI.235

Physical features VI.235

Sections of strata YI.237-244; Till, 14, 28-31

Quaternary deposits VI, 236 ; VLTJ, 12, 14

Coal measures VI.238 ; Vin.28-31

Artesian well VI,244

Logan Co.— See Tazewell, McLean, Logan and Mason counties.
Macon Co.— See Moultrie, Macon and Piatt counties.

Macoupin Co.. (A. H. WOBTHEX) Y, 286-305

Physical features V.286

Sections of strata V.287-295; VII, 12; Tin.51

Quarternary deposits Y,286,305

Coal measures 1,2.6; Y.287-301 ; YII.12

Economical Geology, (coal, building stone, lime, iron ore. fire clay,
sand and clay for bricks, agriculture) V.301

Madison Co., (A. H. WOETHEN) 1,313-326

Physical features '. 1,313

Sections of strata 1,59,317-321

Quarternary deposits 1,314

Coal measures 1,59,316; VII, 10

Chester group 1,321

St Louis limestone 1,321

Keokuk geodiferous sha;es 1,322

Economical Geology, (coal, clays, lime, building stone) 1,322

Marion Co., (HEXBT EXGELMAXN) 113,172-218

Physical features 111,192

Sections of strata ffl.194-203; YI,5; VH.9; VTQ, 18.41-44

Quarternary deposits VLLL, 18

Coal measures ni,193; VI.5; VH.6,9; VHI.41-44

Economical Geology, (coal, iron ores, salt, building materials, agri-
culture) 1 IH.215

Marshall and Putnam Counties, (JAMES SHAW) V, 202-216

Physical features V, 202.211

Sections of errata V.208,211; Vn,29; Vm,13

Quaternary deposits V, 203,213

Coal measures V, 204, 214

Economical Geology, (coal, building materials) V, 209,216

Mason Co.— See Tazewell, McLean, Logan and Mason Counties.

.iC CO.. (HEXBY EXGELMAXX) 1,428-455

Physical features 1,428

Sections of strata 1,441,445

52 GENERAL INDEX.

Massac Co.. Tertiary and Post-Tertiary formations 1,447

Chester group 1, 438

St. Louis group 1,435

' ' Economical Geology, (lead and iron ores, fluor spar, building mater-
ials, agriculture) 1, 452

Indian remains 1,455

McDonough Co., (A. H. WOBTHEN) V.253-2C5

Physical features V.253

Sections of strata : V.254-261; VII.24

Quaternary deposits V.254

Coal measures V.255; 1,228

" St. Louis group V.260

Keokuk group V, 261

" Economical Geology, (coal, flre clay, iron ore, building materials,

agriculture) V.261

McHenry and Lake Counties (HENBY M. BANNISTEB) IV, 126-135

Physical features IV.126

Sections of strata IV.129; VIII.12

" Quaternary deposits IV, 129

Niagara group IV.131

Cincinnati group IV, 132

Galena limestone (?) IV, 133

Economical Geology, (building materials, peat) IV, 133

McLean Co.— See Tazewell, McLean, Mason and Logan Counties.
Menard Co.— See Cass and Menard Counties.

Mercer Co.. (H. A. GBEEN) IV.301-312

Physical features IV, 301

Sections of strata IV.303-307

Quaternary deposits IV, 302

Coal measures IV, 302

Kinderhook group IV.307

Economical Geology, (building stone, lime, coal, agriculture) IV.307

Monroe Co., (A. H. WOBTHEN) V.266-285

Physical features V.266

Section of strata (longitudinal) V.269

Sections of strata (vertical) 1,112; V.270-278

Quaternary deposits V.267

Coal measures V, 270

Chester group V.272

St. Louis group V.274

Keokuk group V, 277

Burlington group V, 278

Trenton group V, 279

Economical Geology, (building stone, marble, coal, iron ore, hydraulic

limestone, lime, brick materials, agriculture) V.281

Montgomery Co., (G. C. BBOADHEAD) VI, 149-155

Physical features VI, 149

Sections of strata VI, 128, 151-154; VII,27,37; VIII, 46

Quaternary deposits VI, 150

Coal measures VI, 151; VII.27; VIII.46

Economical Geology, (coal, building rock, agriculture) : VI, 153

Natural oil... VII.37

GENERAL INDEX. 53

Morgan Co.. (HENBY M. BAXXISTEB) IV, 149-162

Physical features V, 149

Sections of strata IV.150-1GO; YII,32; VHI,50.66

Quaternary deposits IT, 150

Coal measures IY.151; Vn,32; VI 11,50

St. Louis limestone IV.ltiO

Economical Geology, (coal, clays, building material) IV, 161

Artesian wells Vin, 66

iloultrie. Macon and Piatt Counties, (G. C. BBOADHEAD) VI, i 5-1%

Physical features VI, 185, 189, 194

Sections of strata VI.186-195; Vn,17: VIII. 15,48

Quaternary deposits VI, 186, 190, 195; VIII, 15

Coal measures VI,187,193; VII. 17; VIH.48

Agriculture and water VI, 188, 192, 196

Ogle Co., UAMES SHAW) V.104-123

Physical features V, 104

Sections of strata V, 107

Quaternary deposits V.107, V ill, 10

Cincinnati group V, 110

Galena limestone V.lll

Blue limestone V.113

Buff limestone , V.115

St. Peter sandstone V, 115

Lower Magnesian limestone V.118

Economical Geology, (stone, peat, clays and sand, agriculture) V.119

Peoria Co., (A. H. WOBTHEN) V.235-252

Physical features V.235

Sections of strata 1,53,230; V.236-245

Quarternary deposits V.235

Coal measures 1,52.229; V.238; VH.6

Economical Geology, (coal, building stone, iron ore, cla>s, sand,

gravel, agriculture) V.247

Analyses of coal V.248

Perry Co.. (A. H. WOBTHEN and E. EXGELMAXS) 111,84-103

Physical features 111,84

Sections of strata 111,86-96; Vm,56

Quarternary deposits m,86

Coal measures 1,220; D3.87; VHI.56

Economical Geology, (coal, iron ores, building stone, sand, clay, ag-
riculture) 111,97

Analyses of coal 111,98

Salt wells VH.38

Piatt Co.— See Moultrie, Macon and Piatt counties.

Pike Co., (A. H. WOBTHEN) IV, -24-42

Physical features IV, 24

Sections of strata IV, 26,27

Quarternary deposits IV, &5

Coal measures IV, 32

St. Louis limestone „ IV, 32

Keokuk group IV.31

Burlington limestone IV.29

Kinderhook group I V , :.>;

Niagara limestone I V,2<j

Economical Geology, (building stone, coal, iron ore, lime, hydraulic
limestone, clay and sand, marble, mineral springs, soil and timber) JV.37

54 GENERAL INDEX.

Pike Co., Analyses of hydraulic limestone IV.40

" Analyses of mineral water IV.41

Pope Co., (HENBY ENGELMANN) 1,428-495

Physical features 1,428,450

Sections of strata 1,441,445,462

Tertiary and post-tertiary 1,447

Coal measure conglomerates 1,477

Chester group 1,438,460

St. Louis group 1,435,459

Economical Geology, (coal, lead ore, iron ore, fluor spar, epsomite,

building materials, clay, millstones, agriculture) 1,452,484

Indian remains I, ,455,495

Pulaski Co., (HENBY ENGELMANN) 1,410-427

Physical features 1,410

Sections of strata 1, 420

Tertiary and post-tertiary 1,417

St. Louis limestone 1,414

Clear Creek limestone 1, 414

Economical Geology, (iron ore, mineral springs, building stone, clay,
agriculture) 1,423

Putnam Co.— See Marshall and Putnam counties.

Randolph Co., (A. H. WOETHEN) 1,278-298

Physical features 1, 278

Sections of strata 1,77,281

Quarternary deposits ....1,280

Coal measures 1,281

Chester group 1, 40,77, 284 ; VII, 36

St. Louis limestone , , 1,292

Economical Geology, (coal, building materials, agriculture) ..1,293; VII, 36

Richland Co'— See Lawrence and Richland Counties.

Rock Island Co., (A. H. WOBTHEN and JAMES SHAW) V.217-234

Physical features V, 217, 226

Sections of strata V.220-231

Quaternary deposits V,218,233

Coal measures V.219-228; VII, 1

Hamilton limestone V.222, 227

Niagara limestone V, 223

Economical Geology, (building stone, lime, clay, coal, mineral

springs) V, 224, 233

Saline Co., (E. T. Cox) VI, 220-234

Physical features V.220

Sections of strata VI.221-231: VIII.54

Quaternary deposits VI, 232

Coal measures VI.223; VII.4,7; VIII.54

Chester limestone , VI, 221

Economical Geology, (salt, building 'stone, lime, clay, agriculture) ..VI, 232

Sangamon Co., (A. H. WOBTHEN) V, 306-319

Physical features V, 306

Sections of strata V.307-315; VII, 4, 13,28: VIII, 16

Quaternary deposits V.306; VIII, 16

Coal measures 1,227; V.309; VII, 4,6,13, 28

Economical Geology, (coal, building materials, agriculture) V.317

GENERAL INDEX. 55

Schuyler Co.. (A. H. WOBTHEN) IY.75-89

Physical features IV, 75

Sections of strata IV.76,83

Quaternary deposits IV.77

Coal measures IV, 77

St. Louis group IV.84

Keokuk group IV, 84

Economical Geology, (coal, clays, stone, lime, iron ore, and mineral

springs 17,85

Analyses of coal, iron ore and mineral water IV.85-89

Scott Co., (A. H. WOBTHEN) 111,134-144

Physical features 111,134

Sections of strata 111,136-139; VII, 11, 32

Quaternary deposits 113,134

Coal measures 111,136; Vn,ll,32

St. Louis limestone 111,138

Keokuk limestone 111,140

Burlington limestone 111,140

Economical Geology, (coal, clays, iron ore, building materials) 111,141

Analyses of coal m, 141 , 142

Shelby Co., (G. C. BBOADHEAD) VT.16S-174

Physical features VI, 163

Sections of strata VI, 128, 166-170

Quaternary deposits VI, 165

Coal measures VI, 166

Economical Geology, (coal, building and road materials, agricul-
ture) VI, 171

Stark Co., (H. A. GBEEN) IV.325-333

Physical features IV.325

Sections of strata IV.326

Quarternary deposits ". IV, 325

Coal measures IV.326

Economical Geology, (stone, coal, agriculture) IV, 330

St. Clair Co., (A. H. WOBTHEN) 1,297-312

Physical features — ." 1,297

Sections of strata 1,226,299-303; VII, 31; VIII, 19

Quarternary deposits 1,298; VIII, 19

Coal measures 1,224,300

Chester group 1,305

St. Louis Limestone 1,307

Economical Geology, (coal, iron ore, clays, building materials ..1,308

Analyses of coals 1,308,309

Stephenson Co., (JAMES SHA\V) V.57-74

Physical features V.57

Sections of strata I.P1. IV.opp. page 164; V.60

Quarternary deposits V, 62

Niagara limestone V.64

Cincinnati shales V.65

Trenton limestone V.66

St. Peter's limestone V.70

Economic Geology, (building materials, bog-iron, lead ore, peat, ag-
riculture) V.71

See also J. D. WHITNEY'S report on the Lead regions 1,153-207

56 GENERAL INDEX.

Tazewell, McLean, Logan and Mason counties, (H. M. BANNISTEE) 17,176-189

Physical features IV, 176

Sections of strata IV.178-186; 7111,12,14.50

Quaternary deposits IV, 177; VIII.12,14

Coal measures IV.179; VII.4; VIII.50

Economical Geology, (coal, clay, sand, mineral springs) IV, 187

Union Co.. (A. H. WOBTHKN and HENKY ENGELMANN) 111,33-57

Physical features 111,33

Sections of strata 111,35-47

Quaternary deposits 111,50

Conglomerate sandstone 111,50

Chester group 111,44

St. Louis group 111,42

Kinderhook group 1,112; 111,41

Devonian system Ill, 40

Clear Creek limestone 111,37

Lower Helderberg limestone 111,36

Economical Geology, (iron ore, potter's clay, building materials,
marble, mill-stones, mineral springs, agriculture) 111,51

Vermilion Co.. (FBANK H. BBADLEY) IV, 241-265

Physical features IV, 241

Sections of strata IV.244-263

Quaternary deposits IV, 242

Coal measures IV.244; VII, 7,23

Economical Geology, (coal, building materials, flre clay, iron ore,

gold and copper in the drift, salt, road material) IV, 255

" Analyses of coals IV, 257

Wabash and Edwards counties, (A. H. WOETHEN) VI.51-65

Physical features VI, 51

Sections of strata VI , 53-60

Coal measures VI, 52

Economical Geology, (building stone, coal, iron ore, brick material,

potter's clay, agriculture) VI, 60

List of forest trees and shrubs, by Dr. J. SCHENCK VI, 63

Warren Co., (H. A. GEEEN) IV.288-300

Physical features IV, 288

Sections of strata IV.290-299; VIII. 66

Quaternary deposits IV, 289

Coal measures IV, 289

Burlington limestone IV, 295

Kinderhook group IV, 297

Economical Geology, (coal, lime, building stone) IV , 298

Artesian well VIII, 66

Washington Co., (HENEY ENGELMANN) Ill, 145-171

Physical features Ill, 145

Sections of strata 111,162,164; VII, 10

Coal measures 111,148 ; VII, 10

Economical geology, (coal, building materials, agriculture) 111,169

Wayne and Clay counties, (A. H. WOETHEN) VI.82-97

Physical features VI, 82, 88

Sections of strata VI, 83-95

Quaternary deposits VI, 89

Coal measures VI, 83, 89

Economical Geology, (building materials, coal, potter's clay, iron
ore, mineral springs, agriculture) VI,87,95

GENERAL INDEX. 57

White and Hamilton Counties, (A. H. WOBTHEN) VI,66-81

Physical features VI, 66,75

Sections of strata VI. 67-78

Quaternary deposits VI, 66, 75

Coal measures YI,67,75

Economical Geology, (coal, building materials, mineral springs, agri-
culture) VI.73,79

Whiteside Co., (JAMES SHAW) V.140-166

Physical features V.140

Sections of strata V,140

Quaternary deposits V.140; YHI,11

Coal measures, including Conglomerates V, 146

Niagara limestone V.149

Cincinnati shales YI.152

Galena limestone V, 154

Economical Geology, (building materials, peat, vine and agricul-
ture) V.155

Tables showing properties of stone V, 157, 158

Will Co.. (FBAXK H. BBADLEY) IY.207-225

Physical features IV,2U7

Sections of strata 1,55-57; IV.213-219

Quaternary deposits IV, 208

Coal measures 1, 54-57 ; IV.209

Niagara limestone IV, 213

Cincinnati group IV, 216

Trenton limestone (?) IY.219

Economical Geology, (coal, building materials, water) IV, 219

Artesian borings IV.224

Indian mounds IV, 222

Altitudes in Will Co IY.224

Williamson and Franklin Counties, (A. H. WOBTHEN) YI.112-127

Physical features VI, 112, 122

Sections of strata VI, 114-125

Quaternary deposits VI, 113, 123

Coal measures VI.113,123; VH.7

Economical Geology, (coal, building materials, iron ore, agricul-
ture) VI.120,126

Winnebago Co., (JAMES SHAW) V.84-94

Physical features V,82

Sections of strata V,84

Quaternary deposits V.84

Trenton group V, 86

Economical Geology, (building materials, sands and clays, horticul-
ture) V.90

Indian antiquities V,93

Woodford Co,, (H. A. GBEEK) IY.334-342

Physical features v IT, 334

Sections of strata IV, 336

Quaternary deposits IT. 335

Coal measures IV, 337

Economical Geology, (building stone, coal, agriculture) 1V.340

Cretaceous fossils in the drift of Illinois VIII, 3

strata in Iowa, by C. A. WHITE VHI.6

—8

58 GENERAL INDEX.

Devonian system 1,119-152; Il.xi; 111,393; YIII.63

Dikes, how formed 1, 23

Disturbed strata '. 1,5-9,458; IV.2; VII,39,41

Driftless region of the Northwestern counties 1,28,160

Drift— See Quaternary system.

Epsomites 1,492; 111,43

Erosion in Illinois 1,9; IV.237; VIII.3,11, 28,34

Faults 1,458; IV.2

Fish beds 11,11-16; IV.345; VI, 247; VII.59

Flora of Illinois, contributions to 1,280,342,375,406; IV.109; V.158; VI.63

Fluor spar Ill, 19

Fossils, use and value of 1,17

Fusulina limestone VII, 27

Gas, distilled from coal by different methods 1,266

" .natural IV.206; VI.192; VIII,13,58.61

Galena 1,141-149,155-207; 111,301; V.17-21

Galena beds— See Trenton.

Gait limestone 1,130

Gash veins 1, 23

GeoJes of the Keokuk group; by G. J. Brush 1.92

Geological survey of Illinois, history of I.ix-xvi; Il.vi.vii; VI.v; VIII, Appendix, 12

systems, order of 1,21; Il.viii

Geology, general principles of 1. 10; Il.i-v

Glacial theory V.5; VIII.19

Glencoe marble V.282

Glossary of scientific terms 1,497-504

Gold , 1,35; 111,18; 1V.263

Goniatite limestone 1,109

Grindstone grit VII, 37

Hamilton group 1,120: II.xv; 111,22,419

Hard pan 1,25

Helderberg, Lower and Upper II, viii

Hudson river group. 1,137; II,xvi-xix

Huronian system 1,22, 163

Ichthyic beds— See Fish beds.

Illinois, physical features of 1, 2-10

Indian remains 1,455,495; IV.222; V, 93, 102,165; VI, 30, 146,216, 224

Iowa— Cretaceous strata in VIII, 6

" —Marshall county strata and fossils VIII, 157

Iron ores 1, 61, 256 ; V, 263

Kaskaskia limestone 1, 42

Keokuk group 1,89-102; III.508; VII. 16

Kinderhook group 1,43,108-118; II, ix; 111,450; VIII.158

Lake Michigan, ancient outlet of IV.191,237; VIII, 11,14. 28, 33, 36,39

Lakes in Illinois IV.128 ; VI, 173

Lake tunnel, peculiar features of 111,243

Land slides IV, 127

Laurentian system 1, 22, 112

Lead mines in Hardin Co., report by Dr. J. G. NORWOOD 1,366-373

letter from H. M. THOMPSON Ill, 17-16

Lead region, geology of, report by Prof. J. D. WHITNEY 1,153-207

Lignite 1,45,74

Lime, material for 1,324; VII, 40

Limestone, Archimedes II, 13

Athens (marble) 1,133

GENERAL INDEX. 59

Limestone, Birdsey e 1, 147

Blue 1,165; V.21

Buff 1,165: V.21

Burlington 1,102

Carlinville VI. 1; VTI,19

cavernous 1,87

Chester 1.41,77; VII.34

Clear Creek 1, 126 ; II, x

Cliff 1,177

Curlew 1,222

Devonian 1,120; VII.2

Dolomitic 1,32

Fusulina VII, 27

Galena 1.141,169; V.17.36

Gait 1,130

Glencoe (marble) V, 2*2

Goniatiate I.Wi

Hamilton 1, 120 ; VJI,2

Hydraulic 1,324; IV.40; VH.39

Joliet 1,133

Kaskaskia 1,42

Keokuk 1,89; m,508; VH.16

Lithographic 1, 114

Lower Carboniferous, see Subcarboniferous.

Magnesian, Lower 1, 151 ; VII. 39

Upper 1, 177

Mountain=Subcarboniferous.

Niagara 1.129

Onondaga 1,130

Oolitic 1,110

Quarry Creek VI. 10-21

Shoal Creek VI. 1-17

SUurian 1.126

St. Louis 1,83; HI, 17

Subcarboniferous 1, 76-118

Trenton 1,141-148; VH.40

Warsaw VII, 58

Limonite 1, 45, 257

Lithographic stone 1, 114

Loess— See Quaternary deposits.

Lower Carboniferous — See Subcarboniferous.

Coal measures VT, 1

Helderberg n, viii

Magnesian limestones 1,151; Vn,39

" Silurian 1,136-152

Mahoning sandstone HI, 7

Mammalian remains 1,161,162; Vm,8,23

Man, antiquity of 1, 12

Marble— See Limestone.

Marshall group IE, x

Me tamorphic rocks 1, 14, 16

Metallic ores 1,22.35

Millstone grit 1, 48, 82 ; IH.68

Mineral springs— See Water.

Niagara group 1.129-136,177; 111,344

Northwestern counties, by JAMES SHAW ....V.l-24; VHI.10

60 GENERAL INDEX.

Oil distilled from coal 1,72

" " " bituminous shales 1,140

" natural 1,72; VII.37, VlII,58-64

Onondaga group 1, 130 ; II, xiii

Oolitic limestone 1, 110

Oriskany. group 1, 124 ; II, xii

Peat 1,35-37; 111,255; IV, 124,134,148; V,72,102, 120,160

Pentamerus beds 1, 177

Permian rocks 1,47; 111,8

Post-oak flats Ill, 85

Pot-holes in limestone 111,252

Potsdam sandstone 1, 163

Prairies 1,9; V.10

origin of, by LEO LESQUEEEUX 1,238-254

Quaternary system 1, 8-10, 24-39, 160-102, 238-254; Y.4-14; VIII, 1-24

Eecent formations— included in Quaternary.

Salt and"brine-wells IV.22,189; VI,2W,232; VII,31,38

Saltpetre caves 1,405; 111,80

Sandstone, Anvil rock 1,50,213 ; 111,7

Calciferous 1,114,163; 111,280

Ferruginous 1, 42

for glassware VII, 40

Mahoning 111,7

Oriskany 1, 124

Potsdam 1,163

Pulaski Il.xvi

St. Peter's 1,149,164; V.23; VII.39

Thebes 1,139; 111,27

Unionville V.147

Waverly II, x

Scalds : VI.184

Sediments, how accumulated 1,18

Shales.'Bituminous— See Bituminous, and Chemical analyses of.
" Cincinnati— See Cinnati group.

' ' Lorraine II, xvi

Silurian system II, x

Slates of the Coal measures 1,63

" Utica Il.xvii

Springs— See Water.

St. Louis group 1, 83-89 ; VII, 16

St. Peter's sandstone— See under Sandstone.

Stratified rocks, how formed 1,14

Stylolites (read for "crystalites") 1, 115, 116

Subcarboniferous system 1,76-118; II, ix; 111,1,17; VII.58

Terrace epoch. — See Quaternary.

Tertiary system 1,44,417,447; VIII.3

Thebes sandstone.— See under Sandstone.

Trees— See Flora.

Trenton group 1,141-149; VII, 40, 41

Upper Carboniferous.— See Coal Measures.

' ' Coal Measures VI, 1

Helderberg 1,120; II,xiii-xv; 111,407

Magnesian 1,169,177 and PI. 4, opp. p. 162

Silurian 1, 129-136 ; II, xi

Utica slate II, xvii

GENERAL ]NDEX. 61

Vegetation.— See Flora.

Vine culture, report by N. W. BLISS 1.341-349

JAMES SHAW V.158

Warsaw beds 1,89-101 ; VII, 58

Water, artesian.— See Artesian Wells.

" , mineral 1,373,405,491; IV, 22, 40, 73, 89, 148, 189; V.234; VI,80,97; VII, 31, 38

analyses of — See Chemical analyses."
Waverly group 1,101 ; II, x; VIH.160

LIST OF ILLUSTRATIONS.

Geological Map of Hardin Co I.opp. p. 350

Jo Daviess Co., and West part of Stephenson Co I, opp. p. 154

LaSaUe Co Ill, opp. p. 256

The State of Illinois, (scale 6 miles to 1 in.) with VoL VI

(scale 32 miles to 1 in.) Vol. VIII, Appendix.

Map of the Eosiclare lead mines, Hardin Co I.opp. p. 368

Plan of the Good Hope engine shaft at the Bosiclare mines I, opp. p. 367

" and workings of Harbour's Lode, " " I.opp. p. 369

" and workings of Pell's Lode " I.opp. p. 379

' * of lead bearing crevices near Galena, Jo Daviess Co I, opp. p. 192

Sections, vertical, of the Illinois strata I.opp. p. 40

rocks in the lead region of Upper Mississippi I, opp. p. 162

longitudinal of the bluffs of the Mississippi, from Dunleith to Cairo.. I, opp. p. 508

of strata in Calhoun Co., (Cap au Gres bluff) IV.2

Gallatin Co., (Shawneetown) VI.198

Kane and Kendall Counties IV.138

LaSalle Co 111,261

LaSalJe Co IH.270

Monroe Co V.269

View in Jackson Co., "Devil's Bake Oven," Devonian in, frontispiece

"Back Bone" and "Bake Oven," looking north, Devonian

rocks Ill, opp. p. 59

"Back Bone," upper end, looking south, Devonian rocks, in, opp. p. 61
"BackBone," lower end, looking north, Devonian rocks, in, opp. p. 63

Jersey Co., Mt. Vernon bluff, Burlington HI.opp. p. 115

Mason's bluff, Niagara and Subcarbonif erous HE, opp. p. 117

Mason's Landing, Niagara IV, frontispiece

Mt. Radiance, Subcarbonif erous V, frontispiece

Jo Daviess Co., near Galena, lead bearing rocks and furnace I, frontispiece

62

GENERAL INDEX.

B. PALEONTOLOGY.

I. SYNOPTIC

LOWEB SlLUBIAN.

UPPEB SILUBIAN.

DEVONIAN.

Cana-
dian
Group.

Trenton
(and
Galena)
Group.

Cincinnati
Group.

Niagara
Group.

Lower
Helder-
berg
Group.

Corni-
ferous and
Oriskany
Groups.

Hamilton
Group.

Plantse.

(1,152)

KMzopoda.

111,345;
VI, 500.

Spongtae.

Ill, 301-
307;
VI, 491, 492;
VIII, 258...

282.

Ill, 344-

346:
VI, 499.

111,418;
VIII. 251.

Anthozoa.

111,304.

111,368-370

III.407— 410

111,420.

Palaeocrinoi-
dea.

111,324—334
VI, 492, 493.

111,347,349;
VI, 499;
VIII.96,208

111,370.

111,421—423
VI, 510;
VIII, 90.

Cystidea.

111,291—294

111,329—333

Agelacrinoi-
dea.

Blastoidea.

VII, 346-364

Stellerida.

Echinida.

Bryozoa.

VIII, 405...
523.

VIII, 405...
647.

VIII, 463,

499.

VIII, 556...
650.

VIII, 487,
490.

11,423;
VIII, 407...
649.

GENERAL INDEX.

63

TABLE.

SUBCABBONIFEBOUS.

CABBONIFEBOUS .

Kinder-
hook
Group.

Burling-
ton
Group.

Keokuk
Group.

St. Louis
Group.

Chester
Group.

Coal Measures.

II, 453,458,
466*
IV. 451, 474,
475.

II. 425-470;
IV, 375— 508.

Planta.

V.560.

Bhizopoda.

11,146.

VIII, 249.

n,233,234;
VIII, 250.

11,262.

VIIL245— 247.

Spongise.

VHL75.79.

;Vm,72...78

Vm,74...80

Vm,73,78,
82.

V.560; VI.525.

Anthozoa.

11.151;
VII. 285, 310
VIII. 88,%,
165—200.

IL169— 207;
III.463— 495
V, 323—461 ;
VII, 301, 304

11.234—245 :
111,511—521
V. 483— 506;
VI. 514— 519
VII. 269....
:-!14;
VIII, 84...
101.

11,263—274 ;
V. 530— 537;
VI. 518—520
VII. 286...
*"i7 ;
VIII, 89, 99.

11,288—294;
V, 546— 559;
VII, 290...
342;
VIII, 87...
91.

Ill, 310-320;
AV61— 566;
VI. 526— 528;
VII, 317, 343-345.

Palaeocrinoidea.

Cystidea.

V, 513—516

VII, 335-337

Agelacrinoidea.

VIII, 203,
205.

IIL496— 499
V, 461—473

V, 506—509

11,274— 276;
V. 537^539;
VI, 521.

Blastoidea.

in, 499;
V, 474-476.

111,526—528
V, 509, 510

H. 277— 280

VH, 327-331

Stellerida.

11,230;
V, 473— 482.

12.247—251;
III.522— 525
V, 510-513

VII, 338.

11.294—296;
VII, 331-334

VH, 337, 338.

Echinida.

VIII, 428,

619.

111,501-1504
VIII, 429...
652.

II. 412—422
VIII, 429...
677.

II, 413,415.
421;
VIII, 434...
665.

11.421;
VIII, 432...
669.

VIII, 446... 661.

Bryozoa.

64

GENERAL INDEX.

SYNOPTIC

LOWER SILURIAN,

UPPER SILURIAN.

DEVONIAN.

Cana-
dian
Group.

Trenton
(and
Galena)
Group.

Cincinnati
Group.

Niagara
Group.

Lower
Helder-
berg
Group.

Corni-
ferous and
Oriskany
Groups.

Hamilton
Group.

Brachiopoda.

111,305.

III.335— 337

111,349-354
VI, 502.

111,371—384

111,393-404,
410-416.

III.423-437

Pteropoda.

111,341-313

Gasteropoda.

(1,152)

111,312—318

HI, 340.

111,359—363

111,384-390

111,404—406

111,441—443

Cephalopoda.

III, 298,318
—320,496.

VI, 503-508
VIII, 152.

111,444—417
VI, 511-513

Lamelli-
branchiata.

111,294-298,
306-312;
VI, 494— 496

111,337-340
VI, 495. .

111,354-359

VI, 511.

111,437—441

Annelida.

(111,280)

Trilobita.

111,299.300,
320-323.

VI, 497, 498.

111,363-367
VI, 508— 510

111,390—392

111,416—418

111,447—449

Other
Crustacea.

Arachnida,
Myriopoda
aud Insecta.

Pisces.

11.106;
VI, 251— 253

Batrachia.

-.

Fossils of the Cretaceous (Tertiary?) system are referred to in 1,44-46; VIII, 3-5; and
of the Quaternary system in VIII, 8, 9, 15.

GENERAL INDEX.

65

TABLE — Continued.

SUBC AEBOKEFEKOUS .

CABBONTFEBOUS

Kinder-
hook
Group.

Burling-
ton
Group.

Keokuk
Group.

8t Louis
Group.

Chester
Group.

Coal Measures.

11.153—155 ;
111,450-452

III. 505;
VIII, lie.

11.251—254;
III, 528-
532;
VI. 521-524
VII, 321, 322
VIII. !«>>.

11.280;
VIII, 103,
105.

II, 297—299

n, 320— 324;
V, 566-573;
VII. 318;
YUI, 104, 106.

Brachiopoda.

V. 520—522

V.541.

VII. 325;
VIIL134.

Pteropoda.

II, 159,160;
111,457,458.

III.506— 510

VII. 325:
VIII, 137.

H.260;
V. 516— 520;
VIII, 138,
141-144

H, 284— 286,
VIII, 143,
144.

n.302— 304;
VII. 325;
VIII. 141-
145.

n.351— 385;
Y,589—608;
Vm, 135— 147.

Gasteropoda.

IL Ifi2— 165
111,458— 460

VII, 325

V. 022-525

11,286;
V, 543— 545;
VIII, 150.

11,304—309;
VII, 323-
325;
Yin, 149.

H, 386— 393;
V,608-€12;
YI. 531, 532;
VII. 324;
YHI.148,150.

Cephalopoda.

11.157;
III.453— 456
VIII, 115,
118,

11.231;
VIII, 13".

11.256— 258;
111,532-539
VI, 52-
VIII, 108—
133.

11.281—284;
V, 539—541 ;
VII, 326;
VIII, 109...
132.

11.300-302:
VnjK:

vni, 107-

130.

n, 326— 350;
V, 573-589;
VI, 529— 531;
VII.319;
VIII.110...129,

Lamelli-
branchiata.

n,462.

Annelida.

in, 460.

V, 525—529

Y, 612-618.

Trilobita.

VHI, 154

Yin, 153

11,393—408;
111,540—555;
V, 618, 619.

Other Crustacea.

IH409— 411 ;
n,, 556— 568.

Arachnida,
tfyriopoda and
Insecta.

II. i;

VI. 483-488
Vll.261.

n.il;

IV. 355...
374;
VI. 483— 488
VII. 261-
•264.

II.ii.iii;
IV, 356...
368.
VI. 483-
488;
VII, 261-
264.

Il.iii;
IV, 354...
369;
VI. 483— 488
VII, 261—
264.

II. iv;

IV. 3.1s;

VI. 483-488
VII, 261-
264.

H.v;
[V, 347... 372;
VI. 483— 188.
VU, 261-264.

Pisces,

11,135—141.

Batrachia.

—9

66 GENERAL INDEX.

II. FOSSIL PLANTS.

Numbers in full face refer to. pages where diagnoses are given; an asterisk (*) after
the number indicates that an illustration of the species is given on the plates; a cross (t)
after the number indicates that an illustration of the species is given in the text.

Vol. H, Vol. IV,
page. page.

Alethopteris Sternberg and Goeppert 438 391

aquilina Brongniart 438 472

callosa Lesquereux 472

( coxiana Lsqx.) 469

crenulata Brgt 439 392*

oristata Gutbier. 395

dournardii Brgt 439

erosa Gutbier 394

emarginata Goepp 398*

falcata Lesqx 396*

halli Lesqx 394*

hymenophylloides Lesqx 393*

inflata Lesqx 393*

lanceolata Lesqx 398*

longifolia Brgt 469

massillonis Lesqx 438* 472

mazoniana Lesqx 391*

muricata Brgt 395

nervosa Brgt 472

oweni Lesqx 439

pectinata Lesqx 469

pluckneti Brgt 395

Pennsylvania Lesqx 469

( rugosa Lepqx) 469

serlii Brgt 439 472

solida Lesqx 397*

spinulosa Lesqx 396*

stellata Lesqx 440* 472

Annularia Brongniart 444 422

calamitoides Schimper 423

inflata Lesquereux 423*

longif olia Brongniart 473

(Brgt?) Lesqx 422*

sphenophylloides Unger 469 473

Aphlebia Presl 410,414

Artisia Sternberg 446

' ' transversa St'-rnb 446 474

Asterocarpus Auctorum

grandis Lesqx 469

GENERAL INDEX. 67

VOL n. vol. rv.

page. page.

Asterophyllites Brgt 444 424

equisetiformis Brgt 444 473

fob'osus Lindley and Hutton 469 424

grandis Lindley and Hu ton 424

lanceolatus Lesqx 444 473

longifol us Goeppert 444 424

ovalis Lesqx 473

rigid us Brgt 469 424*

sublaevis Lesqx 444 473

tuberculatus Le^qx 424

Bythrotrephes Hall VILE, 255,280

Calamites Suckow 446

approximatus Brgt 445 474

bistriatus Lesqx 445 473

cistii Brgt 445 473

cruciatus Sternberg 445 473

nodosus Brgt 464 473

pachyderma Brgt 445 473

ramosus Brgt 445 473

suckowi Brgt 445 421

undulatus Brgt 474

Callipteris Brgt 440

sullivanti Lesqx 440* 468

Carpolithes Sternberg *460 463

bullatus Lesqx 463*

cistula Lesqx 461* 475

eorticosus Lesqx 462*

fasciculatus Lesqx 461* 475

' ' jacksonen-is Lesqx 461* 475

multistriatus Sternberg 460* 475

persicaria Lesqx 462*

vesicularis Lesqx 462*

Caulopteris Lindley and Hutton 458 457

acanthopora Lesqx 458*

insignis Lesqx 459* 475

intermedia Lesqx 459

obte^ta Lesqx 457*

wortheni Lesqx 459* 475

Chondrites Sternberg 379

colletti Lesqx 379

Cordaites Unger 443 420

augustifolia Lesqx 420

borassif oLa Unger 443 473

Dictyopteris Gutbier 388

rubella Lesqx 388*

obliqua Bunbury 389

Distribution of Fossil Plants, stratigraphical and geographical 500

' ' in Illinois 471

Equisetites Sternberg 425

occidentals Lesqx 425*

Fossil Flora of the Illinois Coal fields 468 471

' ' plants affinities of 489

modes of preservation of 478

68 GENERAL INDEX.

Vol. II, Vol. IV.

page. page.

Halonia Lindley and Hutton 450

tuberculata? Brgt 451

Hymenophyllites Goeppert 436 410

adnascens Lindley and Hutton 414*

alatus? Geinitz 437* 411

arborescens Lesqx 415*

clarki Lesqx 438* 416*

delicatulns Brgt 412

furcatus Brgt 470

var. membranaceus Gutb 413

gutbieranus Presl 438 416

hirsutus? Lesqx 437 473

inflatus Lesqx 414*

' ' lactuca Gutbier 415

mollis Lesqx 418*

myriophyllum Brgt 412

pinnatifidus Lesqx 436* 473

schlotheimi Brgt 412

spinosus (Goeppert) 436* 473

splendens Lesqx 413*

strong! Lesqx 417*

tenuifolius Brgt 413

thallif ormis Lesqx 417*

trichomanoides Brgt 411

tridactylites Brgt 411

Knorria Sternberg and Goeppert 466 445

' ' imbricata Sternberg 445

" selloni Sternberg 415

Leiodermarize Goldenberg 450

Lepidodendron Sternberg 451 428

clypeatum Lesqx 455 474

costatum Lesqx 453* 474

cruciatum Lesqx 432*

diplotegioides Lesqx 452* 474

elegans Brongniart 433

forulatum Lesqx 431*

gracile Brgt 433

? greeni Lesqx 433*

modulatum Lesqx 430

morrisianum Lesqx 430*

mamillatum Lesqx 432*

obovatum Sternberg 455 474

obscurum Lesqx 453* 474

( ornatissimum Brgt) 436

radicans Lesqx 454* 474

ringens Lesqx 429*

rugosum Brgt 433

simplex Lesqx 454* 474

tijoui Lesqx 431*

turbinatum Lesqx 453* 474

veltheimianum Sternb 455 474

wortheni Lesqx ..452* 474

GENERAL INDEX. 69

Vol. H, VoL IV.

page. page.

Lepidophloyos Sternberg 457 439

auriculatus Lesqx 439*

laricinus Sternb 440

obcordatus Lesqx 457* 440

protuberans Lesqx , 440*

Lepidophyllum Brongniart 456 443

auriculatum Lesqx 457*

foliaceum Lesqx 444*

lanceolatum Brgt 456 474

majus Brgt 456 474

rostellatum Lesqx 443*

striatum Lesqx 443*

Lepidostrobus Brongniart 455 440

connivens Lesqx 442*

hastifolius Lesqx 456 474

lancifolius Lesqx 442*

oblongifolius Lesqx 441*

ornatus Brgt 443

ovatifolius Lesqx 441*

princeps Lesqx 455* 474

truncatus Lesqx 442*

sp. Lesqx 440*

Lycopodites Brongniart 447 426

annularifefolius Lesqx 426*

asterophyllitif olius Lesqx 447* 474

meeki Lesqx 426*

Megaphytum Artis 457

mac-layi Lesqx 458* 475

protaberans Lesqx 458* 475

Neuropteris Brongniart 427 380

angustifolia Brgt 467

capitata Lesqx 383*

clarksoni Lesqx 428 471

collinsi Lesqx 382*

coriacea Lesqx 387*

crenulata Brgt 468

desori Lesqx 430 471

eveni Lesqx 430* 471

fasciculata Lesqx 381*

flmbriata Lesqx 384*

flssa Lesqx 432

flexuosa Brgt 428 471

heterophylla Brgt 430 471

hirsuta Lesqx 427* 380

inflata Lesqx 431* 387

loschii Brgt 428 471

microphylJa Brgt 467

pachyderma Lesqx 430* 471

plicata Sternb 428 471

rarinervis Bunbury 428 386*

rotundifolia Sternb 428 ' 471

tenuifolia Brgt 428 471

verbenifolia Lesqx 431* 385*

vermicularis Lesqx 385*

villiersi Brgt 429 471

70 GENERAL INDEX.

Vol II, Vol. IV.

page. page.

Odontopteris Brongniart 432 390

asqualis Lesqx 434* 472

bradleyi Lesqx 390*

heterophylla Lesqx 433* 472

schlotheimi Brgt 391

subcuneata Bunbury 433* 390*

wortheni Lesqx 432* 472

Pachypteris Brongniart 419

gracillima Lesqx 419*

Palaeophycus Hall VIII, 255

Palseoxyris Brongniart 464

appendiculata Lesqx 465*

' ' corrugata Lesqx 466*

prendeli Lesqx 464*

Pecopteris Brongniart 441 399

abbreviate Brgt 441 403

acuta Brgt 442 472

arborescens Brgt 442 472

arguta Brgt 402*

aspidioides Brgt 403

bucklandi Brgt • 401

callosa Lesqx 442*

candolliana Brgt 401

' ' chserophylloides Brgt 448 404

cisti Brgt 441 472

( " cristata Gutbier) 395

( " ) crenulata Brgt 439

cyathea Brgt 469 472

dentata Brgt 40t

( ' ' elegans Germar) 403

( ' ' erosa Gutbier) 394

' ' flavicans ? Presl 404

grandini Brgt 469

" hemiteloides Brgt 401

lepidorrhachis Brgt 442 472

( " miltoni Brgt) 441

( ," muricataBrgt.) 395

murrayana Brgt 443 472

nervosa Brgt 442

" newberryi Lesqx 443 472

oreopterides Brgt 442 472

plumosa Brgt 442 472

polymorpha Brgt 441 472

pteroides Brgt 441 472

sillimani Brgt 401

squamosa Lesqx 400*

strongi Lesqx 399*

unita Brgt 442 472

' ' var. elegans (Germar) 403

velutina Lesqx 442 472

villosa Brgt 442 402

Pinnularia Lindley and Hutton 461

capillacea Lindl. and Hutt 462 475

(Polypodites elegans Germar) 403

GENERAL INDEX. 71

Vol. n. Vol. IV,

page. page.

Rhabdocarpus Goeppert and Berger 461

clavatus Hernb 461

mamillatus Lesqx 461

Rhizolites F. Braun 453

Schizopteris Auctorum 411

anomala Brgt 419

) mollis Lesqx 418*

Schutzia Goeppert — 427

bracteata Lesqx 427*

Selaginites BroDgniart 446

carvifolius Lesqx 446 474

crassus Lesqx 446* 474

uncinatus Lesqx 446* 474"

Sigillaria Brongniart , 448 445

alternans Lindley and Hutton 447

brardei Brgt : 451 475

cisti Brgt 447

corrugata Lesqx 445*

intermedia Brgt 451 475

massiliensis Lesqx 446*

( •' menardi Brgt) 450* 435

monostigma Lesqx 449* 446*

reniformis Brgt 451 475

sculpta Lesqx 450 474

spinulosa Germar 477

tesselata Brgt 451 475

yardleyi Lesqx 451 475

Sigillariae semina 463

Sigillarioides Lesquereux 449

radieans Lesqx 449*

stellaris Lesqx 450*

Sphenophyllum Brongniart 444 421

cornutum Lesqx 421*

emarginatum Brgt 444 421

filiculme Lesqx 422

schlotheimi Brgt 444 473

Sphenopteris Brongniart 435 408

abbreviata Lesqx 436 473

elegans Brgt 410

( " flavicans? Presl.) 404

gracilis Brgt 408*

irregularis Sternb 435 473

latif olia Brgt 435 473

mixta Schimper 409*

obtusiloba Brgt 435 473

paupercula Lesqx 435* 473

rigida Brgt 435*

scaberrima Lesqx 408*

( " sinuosa Lesqx 409

trifoaata Brgt 410

Staphylopteris Presl 405

asteroides Lesqx 406*

sagittata Lesqx 4C7*

stellata Lesqx 405

wortheni Lesqx 405*

72 GENERAL INDEX.

Vol II, Vol. IV,

page. page.

Stigmaria Brongniart 447 451

' ' anabathra Corda 448

elliptica Lesax 451*

( " ?) eveni Lesax 448*

flcoides Brgt 447 452

" var. reticulata Goeppert 448

" stelluta Goep 448

" undulata Goep 448

minor Goep 448

umbonata Lesax 448 452

undulata Goep 448

Stigmarioides Lesquereux 452

afflnis Lesax 455*

eveni Lesax 453, 475

linearis Lesax 455*

? rugosus Lesax 470

selago Lesax 456*

' ' truncatus Lesax 453*

tuberosus Lesax 453*

villosus Lesax 454*

Syringodendron Sternberg and Brongniart 451 448

cyclostigma Brgt 449

pachyderma Brgt 451 475

pes-capreoli Brgt \ 448

porteri Lesax 448*

Trigonocarpus Brongniart 460 460

juglans Lesax 460* 475

noeggerathi Lindley and Hutton 460*

olivaeformis Lindl. & Hutt 460

rostellum Lesax 460* 475

Ulodendron Ehode 434

ellipticum Sternb 436*

elongatum Lesax 437*

majus Lindl. and Hut 435*

punctatum? Sternb 438

III. FOSSIL ANIMALS.

Abracrinus d'Orbigny 11.147

Acantherpestes Meek and Worthen 111,559

major M. & W Ill, 5591

Acanthocladia King VIII, 398, 627, 635

americana Swallow VIII.636

anceps Schlotheim VIII, 398, 635*

fruticosa Ulrich VIII, 635*

Acanthocladiidae Zittel (Ulrich) VIII,361,397

Acanthoclema Hall VIII, 402, 661

alternatum Hall VIII.666

confluens Ulrich VIII, 662*

hamiltonense Hall (Nicholson) VIII.648

( " ) scutulatum Hall VIII, 64<*

GENERAL INDEX. 73

Acanthoconia Hinde ., V ill, 238

Acanthopora Young and Young VIII.358

Acanthops 111,567

Acanthotelson Meek and Worthen 11,399; 111,549

even! M. & W ITT. 551t

( " insquale M. & W.) 11,403*. PL 32 flg. 7; UI.552

stimpsoni M. & W H.401*; EH, 549+

Achatina Lamarck 11,337

Acidaspis Murchison Ill, 390

hamata (Conr.) 111,390*

Aclls Loven V.596

' ' minuta Stevens TJ.383

" robusta Stevens V.596*

Acondylacanthus St. John and Worthen VI, 432; VU.241

aequicostatus St. J. & W VI, 434*

gracilis St J. & W VI, 433*

jenkinsoni (McCoy) VI, 433

junceus (McCoy) VI,433

mudgianus St. J. & W Vn,244*

nuperus St. J. & W VH.242*

occidental (N. & W.) '. VI.433

( occidentals St. J. & W.) VTJ.238*

rectus St J. & W Vn,241*

tenuistriatus (Bom'sky) VI.433

(?) xippias St. J. & W Vn,244*

Acroculia Phillips HJ, 385

( " ) sigmoidalis PhiUips HL385

( " ) vetusta (Sby) in,385

Acrocrinus Yandell VU, 343

wortheni Wachsm VH, 343t*

Acrogenia Hall VTIT.,388

(ActaeoneUa d'Orbigny) elliptic* Zekeli 11,368

( " ) obtusa Zekeli H.,368

( " ) reynauxiana d'Orb 11,368

Actasonidze H, 369

Actseonina d'Orbigny V.594

minuta (Stevens) V.594*

Actinoceras Brown 11,287

(Actinochonchus paradoxus McCoy) 11,254

Actmocrinidffi V.327.329,339; VIII,163

Actinocrinus Miller 11,147,173.188,195,200; 111,470; V, 323, 329, 330, 339, 347; VUI,97,163

( " ) aegilops Hall U.190; V.349

sequalis Hall 11,150

aequibrachiatus M. Ch n,150,207

( " var. alatus Hall) H.207

amplus M. & W IH,470t*

( " ) araneolus M. & W 11,198*

armatus Kon 11,149; V.340

arnoldi W. & Sp VIH.168*

( ' ' asterias McCoy) V, 341

asteriscus M. & W 11,150,207*

biturbinatus Hall 11,150

brevicornis HaU II. 211

brevis HaU) 11,210

brontes HaU V.341

caelatus HaU V.341

74 GENERAL INDEX.

Actinoerinus cancellatus Hall , 11,149; V, 549

( " chloris Hall) V.341,345; VIII.163

christyi Shum 11,150; 111,347

( " ) christyi Hall 111,347

clarus Hall 11,149; V.841

clavis Hall V,341,347,349

clypeatus Hall II, 150

( " ) concavus M. & W 11,215

concinnus Shum 11,149,200*. 202t; 111,476; V.341

conicus L. & C II, 150

corniculum Hall 11,210

costatus Hall II, 149

costus McCoy II, 192

daphne Hall VIII, 163

delicatus M. & W V.341, 343*

deornatus Kon V.340

depressus L. & G 11,150

" diversus Kon V.340

divergens Hall Ill, 472

dodecadactylus M. & W II,205*,206t

dorsatus Kon II, 149

erodus Hall 11,190

euconus M. & W II, 150

excerptus Hall V, 341

formosus Hall ~ II, 150

fosteri M. Ch V.341

glans Hall V.349

( " ) glyptusHall 11.190; V.349,355

hazeri M. Ch 11,150

( " ) helice Hall VIII.176

humboldtianus Hall V.341

hurdianus M. Ch 11,149; V.341

icosidactylus Cass II, 150

indianensis L. & C V.341

infreauens Hall V, 341

inornatus Hall 11,150,209

( " ) insculptus Hall V.349

irregularis Cass II, 150

jugosus Hall V.341

limibraehiatus Hall V.341

( " ) liratus Hall 11,190; V, 347,349

lobatus Hall V.341; VIII,97*

locellus Hall V.341

longirostris Hall 11,191

longus M. & W V.341, 345*

lowei Hall 11,149; V.341

lucina Hall V.343

minor Hall II, 211

multlbrachiatus Hall : II, 149; V, 340,341,343

multiradiatus Shum.? 11,149; V, 341

( " nashvillse Troost) VIII, 85

nodobrachiatus W. & Sp VIII, 165*

oblatus Hall II, 149

opusculus Hall V, 341

ornatissimus W. & Sp VIII, 163*, 165, 167

ornatus M. Ch 11,149

GENERAL INDEX. 75

Actinocrinus ovatus Hall * Y.341

penlcillus M. & W Y.341,342*

( " )pentagonus HaU n,191,196t; m,474*

pernodosus Hall Y.341

( " Jperumbrosus Hall n,188t: Y.339,347

pisttlliformis M. & W n,150,151*; HI, 474

pistiUns M. & W n.150; m, 472*

planobasalis Hall 11,210

planodiscus Hall n, 150

poljrdactylus Miller 13,149; Y.340

proboscidalis Hall 11,149; V,328*,330*,332*.:«l; Vm,165

pyrtformis Shum n,150,15S; HI, 474

var. rudis M. & W 11,153

duaternarius Hall V, 341

var. spiniferus Hall V.341

( " )regalis HaU n,189,191t,192t*,194t; V.349

retlculatus HaU Y.341

rotundatus Shum 11,150,191,206

rudis HaU : n,153; Y.349

( " rusticus HaU' 11,202,205; V.341

scitulus M. & W n,282*,204t: V.341

{ " )sculptus HaU n,197t; V.343*

securis HaU V.328,341

sexarmatus HaU 11,149: V.341

( " silUmani M. & W) n,202,204t; Y.341

simiUs Hall n, 150

sinuatus HaU n, 150

f " speciosus M. & W.) 11,192

( " ) speciosus HaU 111,347

steUaris Kon. and Leh n.149,201; V.340

( " ) subturbinatus M. & W H,212t*

( " )subumbrosus HaU 11,190; V.349

subventricosus M. Ch 11,149; V.349.H64

superlatus HaU 11,211

( " ) tenuiradiatus Hall V.349

tenuisculptus M. Ch Y.341; YIH.163

thah'a Hall Y.341

themis HaU Y.341

thetis HaU V.341

thoas HaU V.341

( " )tholus HaU Y.349

triacontadactylus MiUer H.I49; Y,339,340

( " )trinodis Hall H.213

( " )umbrosus Hall II,190;iY,349

unicomis HaU 11,211

unicostatus Hall Y.341

( " vaUdus M. & W.) 11,200

ventrieosus HaU 11,149; Y,335,339,347,349

verneuili Troost H, 191

verrucosus HaU Y.341

wachsmuthi White Y.341

( " )whitfieldi HaU : HI,347

yandelU Shum Y.341

(Actinostoma Young and Young) YIII,358,359

Actinostroma Nicholson Vin,221, 282

(?) trentonense Uh-ich and Everett Yin, 282*

76 GENERAL INDEX.

Actinotrypa Ulrioh VIII.386,503

peculiaris (Rominger) 386, 503*

(Actinurus) boltoni Bigsby VI.508

Adelophthalmus Jordan and Von Meyer 111,546

(?) mazonensis M. & W IH.547

^Egilops Hall '. 111,310

^Etobatis Miller n,59; VI.299; VII.200,229

Aganides Montfort 11,165,393

compactus M. & W V.612*

" (?) globulosus M. & W 11,393

" (?) iovensis M. & W 11.393

" (?) lyoni M. & W 11,166

Agaricocrinus Troost 11,173,191,210 ; V.397.499; ¥111,94,96,178

americanus Roem "" V.500; VI.517; VIII.94

bullatus Hall V.399

mac-adamsi Worthen VIII, 94*

nodosus M. & W V.397*

nodulosus Worthen VIII, 94*

pentagonus Hall II, 210

tuberosuslTroost V, 500

whitfleldi Hall V.499*

Agassizocrlnus Troost V.556,566; VII.315

" carbonarius Worthen V.566*

' ' chesterensis Worthen V, 558*

conicus 0. & S V.557*

dactyliformis Troost V.P1. xxi.flg. 7*

gitibosus Hall V.558*

globosus Worthen V, 557*

hemisphaericus Worthen VII, 316*

papillatus Worthen VII.315*

pentagonus Worthen V, 556*

Agassizodus St. John and Worthen VI, 297, 299, 311

corrugatus (N. & W.) VI.323*

denticulatus (N. & W.) VI.317

scitulus St. J. & W VI.322*

variabilis (N. & W.) VI, 317, 318*, 322, 323

virginianus St. J. & W VI.321*

Agelaerinidse V.513; VII.335

Agelacrinoidea VII.335

Agelacrinus Vanuxem V.513; VII.335

' ' hamiltonensis Vanuxem V, 515

kaskaskiensis Hall V, 514

parasiticus (Picttst) V, 515

(Lepidodiscus) squamosus M. & W V.513*

Allagecrinus Etheridge and Carpenter VII,341

carpenter! Wachsmuth VII, 341*

Allocrinus Wachsmuth and Springer VIII, 206

typus W. & S VIII.207*

Alloprosallocrinus Lyon and Casseday 11,147,150; V,365,368

conicus L. & C V.368

depressus L. & C V.368

euconus M. & W V.368

Allorisma King 111,538; V.585; VIII, 132

costataM. & W V.585*

elongata Worthen VIII.133

geinitzi Meek V, 586*

GENERAL INDEX. 77

AUorisma (Chaenomya?) hybrida M. & W 111,538*

illfhoiensis Worthen VIII, 132*

" lata Swall 11,350

marionensis White VIII,132

( " ) minnehaha Swall V.588*

(?) rhomboidalis M. & W V.541

sinuata M. Ch V.P1. XXII, flg. 2*

(?) subareuata M. & W in, 538

subcuneata M. & Hayd 11,350; VIII.133

sp. indet II, 350*

Amacanthus St. John and Worthen VI, 464

gibbosus (N. & W.) VI, 464*

Amalthea Schumacher ., 111,386

Amblyptems Agassiz IV.348

macropterus Ag IV, 348

Amblysiphonella Stelnman VIII.218

Ambocoelia Hall II, 155

( " gemmula M. Ch.) 11,156

Ambonychia Hall , 111,306, 337, 356

acutirostris Hall Ill, 356*

belUstriata Hall 111,307

casei M, & W 111,337*

illinoiensis Worthen VI.495*

intermedia M. & W 111,306*

mytiloides Hall 111,356

neglecta M. Ch 111,358

obliqua M. & W 111,357*

radiata Hall 111,307

Ammonites Bruguieres II, 162

sp. (in the drift) VIII.4

Amphibamus Cope 11,135

grandiceps Cope II, 135*,136t

Amphicoelia Hall 11,339; 111,357

leidyi Hall 111,358; V.580

neglecta (M. Ch.) 111,358*

Amphigenia Hall Ill, 403

(Amphora sp. Cumberland) 11,209

Amphoracrinus Austin 11,151, 209 ; V.339,386, 484 ; VIII.96

( " ) concavus AL &W 11.215

divergens (Hall) V.387,388*

inflatus (Hall) V.388

" jerseyensis Worthen VIII, 96*

planobasalis (Hall) V.388

(?) spinibrachiatus (Hall) V, 387,389*

subturbinatus M. & W II,212*,213t

trinodus Hall II, 213

Amplexus Sowerby VIII.82

geniculatus Worthen VIII, 82*

Amplexopora Ulrich VIII, 377, 450

affinis Ulrich VUI.450*

cingulata Uh-ich VIII, 308t,309t, 377

pustulosa Ulrich VIII, 451*

robusta UWch VIII,318t

. " septosa Ulrich VIII, 451

superba Foord VIII, 450

Amplexoporidee Uhrich VLU.342,376

\

78 GENERAL INDEX.

Anaclithacanthus St. John and Worthen VI, 442

semicostatus St. J. & W VI.443*

Ananchytes sp. (in the drift) ' VIII, 4t

Anisophyllum Edwards and Haimo VIII.80

iovense Worthen VIII, 80*

Anisopoda II, 399

Anisotrypa Ulrich VIII, 376

elegantula (Ulrich) VIII.365,447

flstulosa Ulrich VIII, 448*

ramulosa Ulrich VIII, 449*

solida Ulnoh VIII, 365, 449*

symmetrica Ulrich VIII, 376, 448*

Anolotichia Ulrich VIII. 381, 473

ponderosa Ulrich VIII,320t, 381, 473*

impolita Ulrich VIII.473

Annulata II, 462

Anomalocrinus Meek and Worthen 111,327

incurvus M. & W III,327t*

(Anomites) rhomboidalis Wahlenb Ill, 426

Anomocladina Zittel VIII, 225, 226, 234

Anomphalus Meek and Worthen V.597

rotulusM. & W V.597*

Antedon (larva) VIII.161

Anthaspidella Ulrich and Everett VIII.217.221. 234,250,257

fenestrata U. & E VIII.234,264*

flrma U. & E VIII,234,263*

florifera U. & E VIII,234,257,259*,263)267

grandis U. & E VIII,234,262*

(?) magniflca U. & E VIII,235,265*

mammulata U. & E VIII. 235, 258*. 263, 267

obliqua U. & E VIII,235,265*

parvistellata U. & E VIII.235,260*

scutula U. & E VIII.235,261*

Anthaspidellidae Ulrich VIII, 221, 234

Anthozoa, 111,304,368,407,420; V.560; VI.525; VIII, 71, 216

Anthracerpes Meek and Worthen 11,409; 111,557

typus M. & W 11,409*

Anthraconectes Meek and Worthen Ill, 546

mazonensis M. & W 111,546

Anthracoptera Salter Ill, 534

carbonaria Salt 111,535

(?) fragilis M. £ W 111,534*

Anthrapalsemon Salter 11,406 ; 111,554

gracilis M. & W 11,407*; 111,554+

grossarii Salt II, 408

Antliodus Newbury and Worthen 11,33,38; IV, 356, 362; VI, 367, 374, 377, 384, 393, 397

cucullus N. & W 11,33,39,41*

gracilis St. J. & W VI,393t

minutus N. & W 11,33,39,43*

mucronatus N. & W 11,33, 38*

parvulus N . & W II, 33, 38*, 52

perovalis St. J. & W VI.393*

politus N. & W 11,33,42*; VI.368

robustus N. & W 11,33,392,42

sarcululus N. & W IV.356*

similis N. & W .- 11,33,41*

GENERAL INDEX. 79

Antliodus simplex N. & W 11,33,39,44*

sulcatus N. & W- 11,33, 42, 45*

? (Chomatodus) truncatus Ag 11,33; VI, 412

Apioceras turbiniforme M. & W 111,444*

Aploceras eurtum M. & W 11,388*

Arachnida Ill, 560,568

Arachnocrinufe M. & W 11,177

bulbosus (Hall) II, 177

(?) pisiformis Boem 11,177

Archegosaurus II, 133

Archaeocidaridae McCoy 11.229, !»4; 111,523; V.510; VII.333

Archaeoeidaris McCoy 11,226,294; 111,523; YII.337

edgarensis W. & Mill YII.337*

illlnoiensis W. & Mill VII, 338*

mucronatus M. & W 11,295*; VII, 337

norwoodi Hall 11,296

spiniclavatus W. & Mill VH.337*

wortheni Hall 11,227

sp. indet. (jaw plate?) VII, PL xxx, flg. 16*

sp. indet V, PI. xxiv, fig. 13*

Archaeocyathus Billings VIII, 211, 216,240

atlanticus Bill VIII, 240

billingsi Walcott VIH.240

(?) pavonoides Matthew VIII,2tO

Archimedes LeSueur (Owen) 111,504; VIII,353, 396. MS

communis Ulrich VIII.568, 573*

compaetus Ulrich VIII, 568, 572*

distans Ulrich VHI,568,578*

grandis Ulrich VIII, 568, 569*

intermedius Uh-ich VIII.568, 574*

invaginatus Ulrich VIII, 568, 575*

laxus Hall VIII,568,580*

meekanus Hall .*. VIII,568, 578*

negligent UMch Vni,568, 569*

owenanus Hall v VIII,568, 570*

perminimus Uh-ich VIII, 568, 572*

proutanus Uh-ich VIII,568, 576*

( ' ' reversus Hall) VIII, 571*

swallovanus Hall Vni,568, 574*

sublaxus Uh-ich VIII.568,579*

terebriformis UJrich VIII, 568, 575*

wortheni Hall VIII, 396, 568, 571*

Architarbus rotundatus Scudder Ill, 568t

Arcidae 11,156

Argonauta gondola Adams V.525

Arthroclema Billings VIII, 2%, 363, 400. 641

angulare Uh-ich VIII, 641*

billiugsi Ulrich VIII, 642

pulchellum Billings Vin, 400, 641*

Arthronema Esch-choltz VIII, 400

( " ) tenue Uhrich VIII, 400

Arthropleura Jordan and Von Meyer 111,559

( " ) ferox Salt 111,559

Arthropora Uh-ich VIII, 349, 393

shafferi (Meek) VIII,308t,393

ArthrostylidEE VIII.362,400

80 GENERAL INDEX.

Arthrostylus Ulrich VIII.363,400

tenuis Ulrich VIII, 400

Articulate 11,393; 111,299.320,363,390,416,447,460,540; V, 525, 612; VI, 497, 508; VIII.153

" (suborder of Palseocrinoidea) VIII, 197

Asaphus Brongniart VI, 497

" (Isotelus) megistos Locke VI.498

( " ) vigilans M. & W VI.497*

Ascoceras Barrande VIII, 151

southwelli Worthen VIII, 151*

Ascodictyum Nicholson and Etheridge VIII, 367

fusiforme N. & E VIII.367

Ascodictyonidse Ulrich VIII. 367

Aspidodus Newberry and Worthen 11,92; VII, 63

convolutus N. & W 11,94*; VII.67

crenulatus N. & W 11,93*; VI.419

Aspidopora Ulrich VIII.373

areolate Ulr VIII.373

(Asteracanthus) siderius Leidy VI.444,445

( Asterocrinus Lyon) 11,288

Asteroidea 11,277; 111.499,526; V.474,510; VII.327

Asteroptychius Agassiz IV.370; VI.435; VII.248

bellulus St. J. & W VI, 439*: VII.249

keokuk St. J. & W VI.436*

ornatus Ag IV, 371

sancti-ludovici St. J. & W VI.437*

semiornatus McCoy IV, 371; VI, 438

tenellus St. J. & W VII.248*

(?) tenuis St. J. & W '. VI.438*

triangularis N. & W IV, 370*; VI, 436

vetustus St. J. & W VI.435*

AstrJEOSpongia Roomer 111,419; VIII.212,217,238

hamiltonensis M. & W III. 419*; VIII.238

meniscus Roem 111,419; VIII.238

Astroconia Sollas VIII.212,238

granti Sollas VIII.238

(Astroita Wolfart) III.407

( Astropodia sp. Ure) 11.179

Astylospongia Roemer 111,344; VI.491,499; VIII, 211, 217, 223, 234

christiani M. & W 111,344*; VIII.234

imbricato-articulata Roem VIII, 234

" inciso-lobata Roem VIII.234

inornata Hall VIII,217,227

(?)parvula Bill VIII.234

(?)perryi Bill '. VIII.234

prasmorsa Goldf VI.499*; VIII,224*,234

var. nux-moschata Hall VIII, 234

roemeri Hinde VIII, 234

stellatim- sulcata Roem VIII, 234

Atactopora Ulrich VIII.377

hirsute Ulrich VIII,277

Atectoporella Ulrich VIII.370,412

ortoni Nicholson VIII. 418

typicalis Ulrich VIII.370

GENERAL INDEX. 81

Athyris McCoy 11,254: V.570; VIII.103

( ' ' paradoxa McCoy)/. 11.254

( " parvirostris M. & W.) 11.254

planosulcata (Phillips) II, 254*

' ' squamosa Worthen VIII.103*

subtilita (Hall) V.570*

Atrypa Dalman 111,430

aspera (Schloth.) HI, 430*

(var. occidentals Hall) 111,430

( " ) comis Ow 111,428

( " )flabellites Conr 111,397

' ' isorhyncha McCoy 11,251

( " ) laevis Yanuxem ins376

( " ) modesta Say HI.378

( ' ' oblonga Sby) H.254

( ' ' obtusa McCoy) H.254

( " ) peculiaris Conr m,395

( " ) planosulqata Phill 11,254

reticularR (L.) 111,431,432*

spinosa fiall in, 450

Aturia Bronn n,165

Aucella McCoy. „ n,S36

Aulocopina Billings Vin,211,240

granti B ill VIII, 240

Aulocopium Oswald VIII,211,214,217,222,225t

Aulopora Goldfvffis VHI.454

Avicula Klein

( " ) eirculus £hum m,453*. V.576

communis Hall .' V.577

( " )cooperensis Shum 11,334; 111,453

lonpa (Geinitz) V.578*

( " magna S'.valL?) 11,258

morganensis M. & W V.576*

( " ) oblonga M. & W 11,258

radiata Phill n,259

{ " ) rectilateraria Cox n, 326

sericea Yern 11,336

subplana Hall 111,355

"(?; undulataM. & W 111,456*

Aviculida? H.156; 111,358

Avieulopecten McCoy 11,231,256,326; 111,532; VI.511; Vn,321; VIII.113

' amplus M. & W 11,257

burlingtonensis M. & W 11,231

caelatus McCoy H, 232

chesterensis Worthen YIII, 115*

circulus (Shum) 111,454

coUetti Worthen VHI, 119*

cooperensis (Shum.) 111,455

coxanus M. & W II, 326*

edwardsi Worthen VIII, 119*

elsahensis Worthen VIII, 115*

hardinensis Worthen VIII, 117*

indianensis M. & W ..' 111,532*

interlineatus M. & W 11,329*

konincki M. & W 11,328*

—11

82 GENERAL INDEX.

Aviculopecten limiformis Wh. & Whitf 11,334; 111,453

mac-whortheri Worthen VIII, 118*

mazonensis Worthen VIII, 117*

menardi Worthen VIII, 120*

" missouriensis Shum 111,455

' ' monroensis Worthen VIII, 114*

neglectus (Geinitz) V,589*

niotensis Worthen VIII, 113*

oblongus M. & W II. 258*

occidental!* Shum.? 11,331*

orestes Worthen VIII, 112*

oweni M. & W 11,256*

papyraceus Sby 11,327

pellucidus M. & W 11,327*

providensis Cox VIII.116*; PI. xxi.flg. 4*

" rectilaterarius (Cox) 11,326

spinuliferus M. & W VIII.116*

talboti Worthen VIII, 114*

unionensis Worthen VI, 511*

varsoviensis Worthen VII,321t; VIII, 113

sp. indet VI, PI. xxxiii, fig. 3

Aviculopinna Meek VIII, 128

illinoiensis Worthen VIII.128*

Axophyllum Edwards and Haime VI, 525

infundibulum Worthen VI, 525*

rude Wh. & St. J VI, 525*

Bactropora Hall VIII,402,662

granistriata Hal] VIII, 402

simplex Ulr VIII, 447, 663::

Bakevellia King 111,535 ; VIII, 126

illinoiensis Worthen VIII, 126*

Baphetes Owen II, 140

Barycrinus Wachsmuth V,483,530; VI.515; VIII.99

bullatus (Hall) V.488

geometrieus M. & W 111,518*; V,485*

herculeus M. & W V.485*

hoveyi (Hall) V.486*

magister (Hall) V, 484

magnificus M. & W V.484

' ' mammatus Worthen V, 486*

pentagonus Worthen V,487*

protuberans (Hall) V.486,488

spectabilis M. & W V.530*

spurius Hall VIII, 99*

4 ' striatus Worthen VI, 515*

subtumidus M. & W V.487*

thomas (Hall) V.532

tumidus Hall VIII, 100*

Baryphyllum Edwards and Haime 111,409,420

(??) arenarium M. & W 111,409*

Batacanthus St John and Worthen VI, 468 ; VII, 253

baculiformis St. J. & W VI.469*; VII.254

" (?)necis St. J. & W VII.253*

(?) pustulosus (Ag.) VI, 468

(?) semigranulatus (Bom'sky) VI.468

stellatus (N. & W.) , VI.470*; VU.254

GENERAL INDEX. 83

Bathychilodus St. John and Worthen VI, 251

mac-isaaci St. J. & W VI, 251*

Batocrimis Casseday 11,147,150,191, 205,209; 111,472; V.364,367; VIII.83,172,174

aequalis Hall 11,150; Y.367

aequibrachiatus M. Ch 11,150,207

( " var. alatus HaU) 11,207*

andrewsianus M. Ch V.367

asteriscus M. & W 11,150,207*

biturbinatus (Hall) 11,150: V.367; V1H,84

calyculoides Hall V.368

calyculus HaU V.367

caricus Hall V.368

caroli (Hall) Vn,307

cassedayanus M. & W Y.370*

christyi (Shum.) 11.150; V, 367, 376,379*

clavigerus Hall Y.367

cloelia (Hall) V.368

clypeatus Hall 11,150

conicus L. & C n,150; V.368

corbulus Hall V, 368

depressus L. & C 11,150; V.368

discoideus HaU H.150; Y.367

dodecadactylus M. & W n,205t*

doris Hall V.367

euconus M. & W 11,150; V.368

formosus Hall 11,150; Y.367

gemmiformis HaU Y, 368

hageri M. Ch n.150; V,368

icosidactylus Cass 11,150; Y.367

inornatus HaU 11,150,209, V, 367

irregularis Cass n,150; Y.367

konincki Shum V, 367

lagunculus HaU Y.367

laura (HaU) Y.378

lepidus Hall .*. V.367

longirostris HaU Y,367,372,PL IX.flg. 11*

mac-bridei W. & Sp VIII,172M74

macniflcus L. & C Y.368

matula HaU Y.368

montgomeryensis Worthen '. YI11, 83*

mundulus HaU V, 367

nashvillee Troost Yin,85*

neglectus M. & W Y.377*

oblatus HaU Y.368

papiUatas Hall Y, 367

pistilliformis M. & W 11,150,151*; 111,474; V.367,376

pistiUus M. & W 11,150; IH,472*; V.367,370

planodiscus (Hall) 11,150: V.367,374

pyriformis (Shum.) 11,150; 111,474; Y.375*

duasiUus M. \- W Y.367,369*

remibrachiatus (Hall) Y.368,370*

rotundatus O. & 8 11,150; V.867

similUs HaU 11,150; V.367

sinuatus HaU II, 150

sinuosus HaU Y.368

subaequaUs M. Ch Y.367

84 GENERAL INDEX.

Batocrinus subconicus Worthen VIII, 84*

trochiscus M. & W « V.372*

turbinatus Hall V.367

" unionensis Worthen * VIII, 84*

urniformis M. Ch V.368

verneuilanus Shum V, 328*, 368,379*

Batospongia Ulrich VIII.218, 239, 246

spicata Ulrich VIII, 238, 246*

Batostoma Ulrich VIII, 379,459

fertile Ulr VIII, 459

imperfectum Ulr VIII, 460*

implicatum Nich VIII.379,459

irrasum Ulr VIII, 460

jamesi N ich VIII, 459, 460

ottawense Foord , VIII, 460,461

variabile Uh- VIII, 460*

Batostomella Ulrich VIII, 375, 432

abrupta Uh- VIII, 435*

gracilis Nich VIII, 375, 432, 434*

interstincta Ulr VIII, 434*

nitida (read nitidula) VIII, 365

nitidula Uh- VIII.365,436*

obliqua Uh- : VIII, 433*

simulatrix Ulr VIII , 432*

spinulosa Uh- VIII.365,375,434*

trentonensis Nich VIII, 433

Batostomellidse Ulrich VIII.341,375

Batrachia 11,135

Beatricea BilUngs VIII.316

Becksia VIII.223

Belemnites sp. (in the drift) VIII, 4t

Belemnocrinus White 111,463

typus White Ill, 464

whitel M. & W 111,463+*

Belemnospongia Ulrich T VIII, 218, 233, 248

fascicularis Ulr VIII, 233, 248*

Belinurus Koenig 11,393 ; 111,457

anthrax (Prestw.) : II, 394, 398

bellulus Koen 11,397

" danae M. & W 11,395 ; 111,547

" rotundatus (Prestw.) 11,397

Bellerophon Montfort 11,160,385; 111,312; VIII.143

bilobatus Sby 111,313

canadensis Bill 111,313

costatus Sby 11,385

crassus M. & W - 111,385*

( " ) curvilineatus Conr II, 160

cyrtolites Hall 11,160*

deslongchampsi (d'Orb.) 11,160

giganteus Worthen VIII, 143s

(Bucania) platystoma M. & W 111,312*

" vasulites Montf 11,385

sp. indet V,P1. xxiii.flg. 2

Berenicea Lamouroux VIII, 368

diluviana Lamx VIII, 368

GENERAL INDEX. 85

Bidiastopora d'Orbigny Yin,337

Bisiphites Montfort 11,307

Blastoidea 11.274; III. 496; V.461, 506,537; VI. 521; VII, 346; VHI.157.201

Blattariae in,567,569

Blattina gracilis Goldenberg 111,569

Borborocoetes Bell n, 133

Bos primigenius Bojanus VUI,8

Botryllopora Nicholson VIII, 384,490

socialis Nich Vm,384, 490*

Brachiopoda II, 153,251, 280,297, 320 ;

in, 305, 335, 349, m, 398, 410, 423, 450, 505, 528; V.566; VI.502.5-J1; VII. 318,321; VEDL.102

Braehiospongia Marsh VUI. 238

digitata (Ow.) Vin.238

Brachiospongidae Beecher V 111, 238

Brachyops Owen * II, 140

Bryozoa Ehrenberg n,412 ; III.oOl ; VIII, 283

Bucania Hall 111,313

" (?) platystoma M. & "W m, 313

Buccinum Linnaeus 11,364,368

acutum Sby II, 368

( " ) arculatum ; 11,368

( " ) breve Sby n,364,368

( " ) imbricatum 11,368

Bulimella Hall n,373

( " ) bulimiformis Hall 11,373

( " ) canaliculata Hall 11,373

( " ) elongata Hall 11,373

Bulimus Scopoli 11,373

Bumastus Murchison VI.508

graftonensis M. & W VI.508

Bursacrinus Meek and VTorthen 111,478

wachsmuthi M. &W m,479+*

Buskopora Ulrich VIII.383,489

dentataUlr VHI,383,489*

lunata (Homing.) Vni.320t,489*

Buthus Leach 111,562

carbonarius M. & W III,562t

Bythiacanthus St John and Worthen VI, 444

van-hornei St. J. & W VI.445*

Bythopora Miller and Dyer .' - . VIII,376

fruticosaM. &D Vm,376

Calamopora Goldfuss VUI, 228

fibrosa Goldf 111,304; VIII, 228

incrastans Phill VIII.382.475

Calathium Billings VUI, 211, 235,250,275

affine Bill VIII.235

anstedi Bill VEH,235

canadense Bill VIII, 235, 250, 275

flttoni Bill VIII.235

formosum Bill VIII, 235

" ??imfelix U. & E VIII. 235, 250. 274*

pannosum Bill VIII,235

paradoxum Bill VIII.235

(Calathocrinus) erodus Hall 11,190

86 GENERAL INDEX.

Calceocrinus Hall V,442,502; VI.510; VIII.92

barrisi Worthen VI.510

(?) bradleyi M. & W V.502*

dactylus Hall V.445

nodosus Hall V.504

robustus Worthen VIII, 92*

tunicatus Hall. V.504; VIII, 93*

ventricosus Hall V, 445

wachsmuthi M. & W V.444*

Calcispongire de Blainville VIII, 220, 239

Callopora Hall VIII, 372, 416

( " ) aspera Hall VIII, 416

( " Cincinnati ensis Ulrich) VIII, 426*

elegantula Hall VIII, 372, 416, 417

( " )floridaHall VIII.416

( " )heteropora Hall VIII.376

( " )laminata Hall VIII.416

( ' ' minutissima Nicholson) VIII, 427*

( " missouriensis Eominger) VIII, 430*

( " ) multiseriata Hall VIII, 376

( " ) nummiformis Hall VIII, 416

( " )oculifera Hall VIII.376

perelegans HaU VIII, 417

( " ) punctata Hall VIII.376, 425, 430

ramosa (d'Orb.) VIII,315t,417

sigillarioides (Nich.) VIII.433

subnodosa Ulrich VIII,308t,417*

( " )unispina Hall VIII.376

Calloporella Ulrich VIII, 373,418

harrisi Ulrich VIII.373, 418

(?)nodulosa Ulrich VIII.418*

Calloporidae Ulrich VIII,339,372

Callotrypa Hall VIII, 376

heteropora Hall VIII.376

multiseriata Hall VIII, 376

oculifera Hall VIII.376

unispina Hall VIII,376

Calliopodus St. John and Worthen VI, 403

apicalis St. J. & W VI, 403*

Camarocladia Ulrich and Everett VIII.217,239,255, 280

dichotoma U. & E VIII,239,281*

Camaraphoria King II, 251 ; VII, 318

giffordi Worthen VII,318t

( ) isoz-hyncha McCoy II, 251

subtrigona M. & W 11,251*

Camerata VIII, 163

Capulus Montfort Ill, 384

Carbonarca Meek and Worthen VI, 530

gibbosa M. & W VI, 531*

Carcharias Eaflnesque 11,35

Carcharodon Smith II, 70 ; IV, 351

Carcharopsis Agassiz 11,69

dentatus (McCoy) VI, 257

prototypus, Ag VI, 253

wortheni Newb 11,69*; VI.255

GENERAL INDEX. 87

Cardiomorpha de Koninck 11,156; V.588: Till, 126

missouriensis Shum V.588*

ovata d'Orbigny 11,157

( " ) ovata Hall 11,157

(?) pellensis Worthen Vm,126*

radiata Kon II, 157

( " ) radiata M. \- W 11,147

(?)sp.Swall 11.317

Cardiopsis Meek and \Vorthen II. 156

radiata M. & W 11,157*

Carinopora Nicholson Till, 395

Castoroides ohioensis Fost VIII.S

Catilloerinus (Troost) Shumard Ill, 465 ;V, 504

bradleyi M. & W V.504*

tennesseas Troost V.505

wachsmuthi M. & "W HI, 465*

Cavea d'Orbigny Vm,665

' ' costata d'Orbigny VEH.665

" regularis d'Orbigny VIII,665

Caveidae d'Orbigny Vni.338

CavidaB d'Orbigny VTQ.SSS

Cellaridae Vffl.362

Cellulines Tm,323

Centrifugines VIII,323

(Centrocrinus Austin) 11,170,172

( Jgigas Gilb 11,17:3

Centrocrinus Wachmuth & Springer YIII,95

tennesseensis Worthen VIII, 95*

Centronella Billings m.352

bilUngsiana M, & W m, 352t*

glans-fagi Bill 111,353

hecate Bill 111,353

tumida Bill 111,353

Cephalopoda 11,161,286,304,386; m,444,459; V, 522, 543, 608; VI, 496,503,511,531; YIII.148

(Ceramella Hall) YIII,387

Ceramopora Hall YTTT, 380, 462

( " ) huronensis Nich YIII,463

imbrieata HaU YIH, 380, 463*

( " ) ohioensis Nicholson YIII, 466*

Ceramoporella Ulrich YIII, 380, 464

distincta Ulrich VIII,380, 464*

granulosa Ulrich YIII. 466*

ohioensis (Nicholson) YIII. 466*

stellata Ukich YIII. 465*

Ceramoporida? Ulrich YIII, 312, 379

Ceraospongia Bronn YIII, 220

Ceratiocaris McCoy 111,540

" (?) sinuatus M. i W 111,540+

Ceratodus Agassiz YI.329

(Ceratophytes) dubius Schlotheim YIII, 606

Cercomya Agas^iz 111,538

striata, Ag 1H, 538

Ceriocava ramosa d'Orbigny Yin,318t

Cerionites Meek & Worthen 111,346

dactylioides M. i; W IH.345*

88 GENERAL INDEX.

Ceriopora Goldftiss 11,417

verrucosa Goldf 11,419

Cestraciontini Bonaparte 11,77,91

Cestracion Cuvier 11,121; IV,a59,365; VI.299,312,319,335,337,347,419; VII.64

Chtenocardia Meek and Worthen V.586

ovata M. & \V V,586*

Chaenodictyum Foerste VIIl,399,fi40

Jaxum Foerste VIII, 399

" var. minor Ulrich VIII, 640*

Chrenomya Meek 111,538; V.540,588; VII.319

" (?) hybrida M. & W 111,538*

maria Worthen VII. 318t

minnehaha (Swall.) V.588*

rhomboidea M. & W V.540*

Chajtetes Fischer 11,419; 111,304; VI.526; VIII.169, WG

( " ?) carbonaria Worthen VI, 526*; VIII, 445*

( " ) flliosa Nicholson VIII, 456*

( " Hycoperdon Say 111,304; VIII.566

petropolitanus (Pander?) 111,304*

( " ) quadrangularis Nicholson VIII, 455

( " ) venustus Uh-ich V1I1, 469

(Cheirocrinus Hall) V, 442

( " tunicatus Hall) VIII.93

( ) wachsmuthi M. & W V.445

Chemnitzia d'Orbigny 11,377

( " attenuata Stev.) V.596*

" subconstricta Kon -, 11,380

Chilostomata VIII, 366

Chiloporella Ulrich VIII, 381

flabellata Ulrich VIII, 381; PI. xxxix.flg. 5*

Ghilotrypa Ulrich VIII, 382

hispida Ulrich VIII, 382

Chiton Linnaeus V, 608

" carbonarius Stev V,608*

Chitonodus St. John and Worthen VII, 61 , 109

antiquus St. J, & W VII, 116*

liratus St. J. & W VII.119*

springeri St. J. & W ....VII, 112*. 119

tribulis St. J. & W VII.117*

Chomatodus Agassiz 11,32,34,51; VI, 354, 356, 366, 384

afflnis N. & W H.34,54*

( " ) angularis N. & W 11,34,55*; VI, 357, 368, 375

angulatus— See C. angularis.

arcuatus St. J VI, PI. x,flg,23*

chesterensis St. J. & W VI.363*

comptus St. J. & W VI, 356*

" (?)costatus N. & W 11,85*

cultelius N. & W 11,34,52*; VI.359

dcntatus MoCoy 11,73

denticulatus McCoy VI, 345

elegans N. & W 11,34,86*; VI.357

elytra (N. & W.) VI,299

gracillimus N. & W 11,34,51*; VI.368

inconstans St. J. & W VI, 360*

incrassatus St. J. & W VI, 359*

GENERAL INDKX. 89

Chomatodus insignis Leidy VI, 359*,364

linearis Ag.... 11,33,34,52; VI.368

loriformis X. & W n.34,50,5S*

molaris X. & W II, SI. 56*

multiplicatus N. & W n,34,50,57*; VI.368

oscurus Leidy VI.368

parallelus St. J. & W VI, 358*

pusillus X. & W 11,34,53*; VI.364

( ) truncatus (Ag.) 11,33; VI.412

varsovien'-is St. J. & W VI.363*

( venustus Leidy.) 11,34; VI.346

Ch"netes Fisher 11,253; in,505; V.566,570

coneentricus Kon V.568

illinoiensis Worthen m, 505*

( " logani Hall) in,505

logani N. & P 111,505

millepunctatus 31 & W V,566*

planumbonus M. i W 11,253

shumurdianus Kon HI, 505

smith! X. & P V.570*

Choristites Fischer 11,321,323

,?) hemiplicatus (Hall) H,323t

lamareki Fischer n, 321

mosquensis Fischer II, 323

Chrestotes Scudder HE, 567

lapidea Scud HI, 567t

Cidaridse n, 226

(Cirrus acutus Sby.) n,363

Cladacanthus paradoxus Ag VI, 451

(Cladoc: inus Austin) ". II, 268

Cladodus Agassiz 11,20: IV.354; VI, 253, 258, 280, 324, 328

alternatus St. J. & W VI.261,265*

angulatus X. & W 11,21, 24*. 25

bellifer St. J. & W YI.270*

carinatus St J. & W VI.279*

costatus X. i W II,25,27*,30

deflexus X. & W IV, 355*; VI.268

excentricus St. J. & TV VI.272*

elegans X. i W IV, 354*

euglypheus St. J. i W VI,274*,280

exiguus St. J. i: W VI, 261*

exilis St. J. & W VI, 258*

ferox X. \- W 11,26*; IV.355

fulleri St. J. & W VI,272,276*.2T8

gomphoides St. J. & W VI, 269*. 271

^raoi.i- X. i W 11,25,28.30*

grandis X. \- W 11,29*

hibberti Ag 11,25, 28

intercostatus St. J. & W VI, 267*, 271, 275

ischypus X. Jc W FV.354*

keokuk St. J. i W VI,268,272

lamnoides N. & W 11,27,30*

magnificus Tuomey .II, 24*,29

micropus X. \- W II,21*,25,29; VI, 258, 271. 282

milleri Ag 11,29

mirabilis Ag II, 33

—12

90 GENERAL, INDEX.

Cladodus mortifer N. & W 11,22*; IV.355

" occidontalis Leidy VI.270

pandatus St. J. & W VL278*

politus N. & W II,27*,30; VI,259,272

praenuntius St. J. & W VI,270*,274

raricostatus St. J. & W VI, 271*

robustus N. & W II,20*,25

simplex Ag '. VI.285

spinosus N. & W II,22*,26; 1V.355

springer! St. J. & W VI, 259*. 263, 279

stenopus N. & W II, 23*

striatus Ag 11,24,26

succinctus St. J. & W VI, 261, 265*

( " ) tenuistriatus Kom'sky VI, 433

turritus N. & W 11,25,28*

van-hornei St. J. & W VI.271,273*

wachsmuthi St. J. & W VI,263*,265

zygopus N. & W 11,25*; VI.268,275

Clausidae d'Orbigny VIII, 338

Clathropora HaU VIII.349,392,4%

( " carinata Hall) VIII, 496

frondosa Hall VIII.392

intertexta Nicholson VIII, 496

Cleodictya Hall VIIL236

gloriosa Hall VIII.236

? mohri HaU VIII, 236

Climacodus McCoy IV.367

Climacospongia Hinde VIII, 217, 223+, 235, 248, 268

radiata Hinde VIII, 2241,235,248

Climatius Agassiz IV, 371

Clinopistha Meek and Worthen V,584; VIII, 122

radiata (Hall) VIII, 122*

" var. levis M, & W V.584*

Clonopora Hall VIII.368

Cnemidiastrum Zittel VIII, 221

Cnemidium Goldf uss VI, 491

( " ) trentonense Worthen VI,491t,492t; VIIL270

Cochliodontidse Owen VII.57, 61,63

Cochliodus Agassiz 11,75,87,92,102,111; IV,362,364; VI, 299, 324, 409: VII, 61, 111, 120

acutus Ag II, 90

contortus Ag IV.365; VII.92,125

( " costatus N. & W.) IV.364*: VII, 167,171

( " crassus N. & W.) II,91*,1<>5; VII.184*

latus Leidy VII, 112, 123

leidyi St. J. & W VIL127*

magnus Ag 11,93; VII, 63

( " ) nitidus Leidy VII, 91, 99

( " nobilis N. & W.) 11,89*; IV.365; VII,112,123

obliauus St. J. & W VIL126*

striatus Ag VII, 175

van-hornei St. J. & W VII, 120*, 127, 130

Codaster McCoy V.463, 468; VII,347, 353

( " ) alternatus Lyon VII, 353

pyramidatus Shum VII, 353

Codasteridae ,.-.,,,.,., , ,,,,...,,,,.,,., , VIII,20l

GENERAL INDEX. 91

(Codonites Meek and Worthen) V,463: VII, 347; YTJI,201

( " ) gracilis M. & W Y,467*; Yin,201

( " ) stelliformis M. & W Y.464*; Till, 201

Coelenterata 111,304.368,407.420: V.560; YI,525: YJT.1,71

Coeliocrinus White 11,179,181

(Coeloclema Ulrich) YIII,380,467

Coeloconus Ulrich YHI, 365, 402, 664

granosus Ulrich YIII. 665*

rhombicus Ulrich YIII, 402, 664*

(Coelocaulis Hall) YIII,382

(Coelocrinus Meek and Worthen) 11,114

( " jconcavus M. & W Il,215t*; YHI.177

Colasteridfe Worthen and Miller YII.328

Colaster W. & M YII, 328

peculiaris W. & M YII, 329*

Colodus St. John and Worthen YI.415

ina?qualis St. J. & W YI.416*

Colpocaris Meek YHI,153

cestriensis Worthen YLH.153*

Comarocystites Billings EH, 291

punctatus Bill 111,293

shumardi M. & W ni,292t*

var. obconicus M. & W HI.294*

Comatula europaea Muller 11,191

Coiubophyllum Edwards and Haime 111,420

(?) arenarium M. & W ITT, 410*

Compsaster Worthen and Miller YII, 327

formosus W. & M YII, 327*

(Conchy liolithus anomites glaber Martin) TJ.,298

Coniopterygida? 111,571

Conocardium Bronn 11,373; YI.529; VUI,112

obliquum M. & W YI, 529*

parrishi Worthen Yin, 112*

(Conocrinus Troost) 11,147,150

Conotubularia cuvieri Troost 111,298

Constellaria Dana YIII. 374,423

flsheri Ulrich YIJJ,425

florida Ulrich YIII,374,423

limitaris Ulrich VIII, 424

polystomella Nicholson YTTJ.424

parva Ulrich YIII, 424*

Conularia Miller 11,373; Y.520,541; YH.325; YIJJ.,134

chesterensis Worthen YII, 325 ; Yin, 134*

nrissouriensis Swall Y, 541*

malticostata M. \- W Y,.i,21

subcarbonaria M. i W Y, 520*

verneuili Emmons Y.'.L'l

Copodus Agassiz VU.200, 227t,228t

cornutus.Ag YJJ.231

pusillus St. J. & W YII.231*

spatulatus Ag YII.231

van-hornei St. J. & W YII.229*

Corynella Zittel YUI.21:.

Coscinella HaU YIII, 388.394, 532

Cpseinium Keyserling 11.412: YUI. 385, 4%

asteria Prout II, 416*

92 GENERAL INDEX,

Coscinium cribriforme Prout VIII,320,496,497*

cyclops KeyserUng VIII.386,496

( " cyclops Prout) VIII.496

( " ) elegans Prout II, 413"

escharense Prout.

( " Jkeyserlingi Prout 11,413

latum Ulrich.

( ) michelini Prout II, 414"

H " ) plumosum Prout II, 414"

( " ) sagenella Prout II, 415*

tuberculatum Prout.

VIII, 518*
...11,416*
VIII, 517*
VIII, 497*
VIII, 515*
VIII, 512*
VIII, 513*
...11,415*

( " wortheni Prout) 11,412* V1II.517*

Coscinopora Goldfuss 111,301

sulcata Goldf Ill, 301

( ' ' sulcata Owen) Ill, 301*

( " ) wortheni Prout II, 412*

(Coscinotrypa Hall) VIII, 385

( ' ' carinata HaU) VIII, 496

Cotylederma Quenstedt 111,371

Cotyledonocrinus Casseday and Lyon 11,167

(Crania) quadrata Eichwald 111,305

Craticularia Zittel VIII,222

Crepipora Ulrich VIII, 380, 409

epidermata Ulrich VIII, 471*

hemisphjerica Ulrich VIII.472*

impolita Ulrich VIII, 473

impressa Ulrich VIII, 471*

simulans Ulrich VIII, 380, 470*, 320t

solida Ulrich VIII, 472*

Crescisidae d'Orbigny VIII, 338

Crinoidea 11,147,167,234,263,288,310; 111,421,463,511; V, 323, 483, 530, 546, 561;

VI, 501, 513, 526; VII, 269, 335, 341 ; VIII, 83, 157, 163

Crisina d'Orbigny VIII, 337

Crisinella Hall VIII.387

Crocodilia 11,137

Crustacea 11,393; 111,299,320,363,390,416,447,460,540; V, 525, 612: VI, 497, 508; VIII, 153

(Cryptoceras d'Orbigny) VI, 532

( " )capax M. & W VI, 532*

( " ) rockfordense M. & W 111,454*

Cryptostomata Vine VIII, 344, 385

(Cryptopora Nicholson) VIII.397

Ctenacanthus Agassiz 11,113,118,121,126; IV, 372; VI, 420, 432, 478; VII, 233, 245

angulatus N. & W 11,118*; VI.431

brevis Ag VI, 421, 444

burlingtonensis St. J. &W VI, 426*

buttersl St. J. & W VII.240*

canniliratus St. J. & W VII.239*

( " eostatus N. & W.) VII.246*

coxanus St. J. & W VII.233*

(?) eostatus N. & W 11,120*

deflexus St. J. & W VII, 234*. 237, 241

distans McCoy 11,117, 119, 127

excavatus St. J. & W VI,428*,431

formosus Newb VI, 422

gemmatus St. J. & W VI, 429*; VII.238

gracillimus N. & W : ...11,117,126*; VI.430; VII.238*

GENERAL INDEX. 03

Ctenacanthus gradato-costatus St. J. & W VI, 425*, 430

harrisoni St J. & W Vn, 236*

hyboides Egerton n, 117, 119

keokuk St J. & W YI,427*.4a5

major Ag H, 117, 119

mayi X. & W IV.372*; VI.426,429; Vn,233

nodosus Egerton n, 119

peUensis St J. & W Vn,237*

pugiunculus St. J. & W ¥1,430*

sculptus St J. & W YI.421*

similis St. J. & W ¥1,431*

speciosus St J. & W VI, 421, 424*; YII,235

spectabilis St J. & W VI, 420*; ¥11,235

varians St J. & W VI, 422*

Ctenodipterinl IY.374

Ctenodonta astartif ormis Salt HI, 309

Ctenodus Agassiz VI, 330

Ctenopetalus Agassiz VI, 368, 383, 396, 413

beUulus St J. & W ¥1,397,398*

dentatus (Ag.) ¥1,354, 399

limatulus St. J. & W ¥1,399*

medius St. J. & W ¥1,400*

occidental St J. & W ¥1,401*

serratus Ag ¥1,397,399,402

vinosus St J. & W ¥1,396*

Ctenoptychius Agassiz 11,33,72; ¥1,382,397

apicalis Ag 11,33,72: ¥1,382,384

digitatus Leidy 11,34

pertenuis St. J. & W ¥1,382*

semicircularis N. & W 11,33,72*

serratus Owen 11,33,72

stevensoni St J. & W ¥1,383*

Ctenostomata Busk YI11, 334,367

Cucullaea Lamarck 111,340

( " ) amygdalina Phil] HI, 340

( " ) angustata Sby 111,340

( " ) unilateralia Sby 111,340

(Cupellocrinus Troost (Shumard) ) 11,170

( " ) tennesseensis Koem 11,172

Cupressocrinus Goldfuss 11,185

abbreviatus Goldf 11,316

( ) Impressus McCoy n, 313

Cyathaxonia Michelin ¥1,526

distorta Worthen ¥1,526*

( " ) prolifera M. Ch ¥.560*

Cyathocrinus MiUer 11,175,181,234,310; 111,481,517; ¥,325,400,484,489; ¥11,309

angulatus M. & W 11,234*

arboreus M. & W 111,520*

(Poteriocrinus) barrisi (Hall) V.401

(Arachnocrinus) bulbosus Hall 11,177

( " )bullatus HaU ¥.488; YIII.IOO

( " )capillaris PhiU 11,182

( " )crassus M. & W n,313

divaricatus Hall v V, 401

enormis M. & W 111,481*; V.406

farleyi M. & W III,517t*; V.401

94 GENERAL INDEX.

Cyathocrinus florealis Y. & Sh V.537; VII,291

fragilis M. & W V.401*

( " ) geometricus M. & W ni,518*; V.485*

( " ) goniodactylus Phill 11,182

( " hamiltonensis Worthen) VII.309*

( " )hoveyi Hall V,4^5,486*

iovensis O. & S V,401

lamellosus Hall .'. V.401

( " ) macrodactylus Phill 11,270

macropleurns Hall V, 412

( " ) magniflcus M. &W V,483*,484

malvaceus Hall V.401

marshallensis Worthen VII, 310*

( " )nobilis Phill 11,270

( " ) ornatissimus Hall 11,182

parvibrachiatus Hall V.490; VII,309*

(?) pentalobus Hall 11,178

(?) perplexus M. & W V.405*

poterium M. & W V.489*

protuberans Hall V, 488

Quinauelobus M. & W III,519t*

rigidus White V.401

rotundatus Hall 11,237; V.401,402

saffordi M. & W II,236*,237t; V.401

sangamonensis M. & W II,310*,311t

sculptilis Hall 11,178*235; 111,520; V.401*

tenuidactylus M. & W ." V.403*

( " )thomse Hall V.532

( " ) tuberculatus Mill 11,270

( " tumidus Hall) 111,519; VIII.100

viminaUs Hall V.401

wachsmuthi M. & W 111,482+*

Cyathophycus Walcott VIII,212, 216,217, 236, 280

quebecence Dawson VIII, 236

reticulatum Walcott VIII.236

subsphaericum Walcott VIII, 236

Cyathophora Michelin Ill, 368

( " ) iovensis Ow 111,368

Cyathopora (?) Owen 111,368

( " ) iovensis Ow 111,368

Cyathospongia HaU VIII,212,234

excrescens Hall VIII, 234

Cyclocrinites Eichwald Ill, 346

Cyclophthalmus senior 111,561

Cyclopora Prout 11,417; VIII, 366, 403, 671

( " ) discoidea Prout 11,420*; VIII,404,674*

expatiata Ulrich VIII, 673

fungia Prout 11,419*; VIII, 366, 403, 671*

( ' ' jamesi Prout) VIII, 671

( " polymorpha Prout) ...11,421*; VIII, 441*

Cycloporella Ulrich VIII, 404, 675

" (?) perversa Ulrich VIII, 676*

spinifera Ulrich VIII, 404, 675*

Cyclostomata VIII, 335,307

Cylindrocoelia Ulrich VIII, 212, 217, 240

endoceroidea Ulr VIII, 240

GENERAL INDEX. 95

Cylindrocuelia covingtonensis Ulr YHI.240

minnesotensis Ulr Yni,240

minor Ulr Till, 240

Cymatodus X. & W IV, 368

oblongus N. & W rv, 364*

Cypricardia Lamarck.

( " ) occidentalis Swall V.580

( " ) randolphensis Worthen Vn,326

Cypricardites Conrad 111,297,309

obliquus M. & W III. 311*

sp. indet III. 311*

Cyrtia triquetra Hall 111,436

Cyrtina Davidson 111,383, 436

acutirostris Shum III. 436

dalmani (Hall) HI, 383*

heteroclita III. 436

triquetra (Hall) in, 436*

Cyrtoceras Golfuss H.388; EH, 445; VI, 496,506

carrollense Worthen YI, 495*

(Aploeeras) curtum 31. & \V 11,388*

dardauus Hall VI, 595*

depressum Golf 11,389

" (?) dilatatum M. & W 11,389*

fultonense (?) M. & W VI.506

heteroclitum Bftrrande in, 446

sacculus M. & W m,445*

(Cyrtodonta Billings) m, 309

( " ) hindi Bill Ill, 339,340

( ) subcarinata Bill in, 312

Cyrtolites Conrad HI.340

compressus Conr HI, 341

( ) deslongchampsi d'Orb n, 160

imbricatu? M. X- W ni, 340*

Cystodictya Ulrich VIH, 385, 486, 491,501,508

americana Ulrich VIII, 492, 494*

carbonaria (Meek) Yin. 4£2

crenulata (Hall) VIII. 492

crescens (HalL VUI,492

gilberti (Meek) VIII, 320*t, 385

hamiltonensis Clrich VHI.493*

incisurata (Hall) VIII, 492

invertis (Hall) VIII. 492

limata (Hall) VIII. 492

linearis (Hall) VIII, 492

lineata Ulrich VIII, 492, 494, 495

var. major Ulrich VIII, 492, 495*

' ' ?ancti-ludovici Ulrich Vin, 492

meeki (Nicholson) Vni, 492

nitida Ulrich VIII. 493*

ocellata Ulrich VTII, 3201,385,492

ovata (Hall) VIII, 492*

ovatipora (Hall) VIII, 492

parallela (Phillips) VIII. 494

perarcta (Hall) VIII, 492

pustulosa UMch VIII, 486, 492. 495*

rectilinea (Hall) VIII, 492

96 GENERAL INDEX.

Cystodictya rigida (Hall) VIII, 492

semistriata (Hall) VIII, 492

sinuosa (Hall) VIII.492

gubrigida (Hall) VIII, 493

sulcata (Winchell) VIII.492.493

trilineata (Hall) VIII, 492

tumulosa (Hall) VIII, 492

vermicula (Hall) VIII, 492

CystodictyonidEO Ulrich '....VIII,346,360,385,481,486,492, 496,504

Cystopora Hall VIII, 360

(Cytocrinus llcemer) II, 151

Dactylethra Cuvier II, 138

Dactylodus Newberry and Worthen 11,33,45; VI. 386, 390

concavus St. J. & W VI, 390*. 392

digitalis (Leidy) 11,34

exeavatus St. J. & W VI. 392*

inflexus N. & W 11,33,48*; VI, 392

lobatus N. & W 11,33,47*

minimus St. J. & W VI, 391*

princeps N. & W 11,33,45*; VI, 390

sarcululus N. & W VI.392

(Dalmania Emmrich=Dalmanites.)

Dalmanites (Emmrich) Barrande 111.363,391,416

(Odontocephalus) aegeria (Hall) ? Ill, 417*

(arenarius?) M. & W 111,417

' ' caudatus Brunnioh '• Ill, 366

danas M. & W 111,363*

limulurus Green 111,367

" micrurus Green 111,367

pleuropteryx Green 111,367

selenurus Conr Ill, 417

tridens Hall 111,392

tridentiferus Shum 111,391*

Deoapoda 11,403,406; 111,552

Defrancia Bronn '• VIII, 337

Dekayia Edwards and Haime VIII. 371, 415

aspera Edwards and Haime VIII, 372,415

devonica Ulrich VIII, 416*

Dekayella Ulrich VIII, 372

obscura Ulrich VIII, 372

Deltodopsis St. John and Wortheu '. VII, 61 , 158

affinis St. J. & W VII, 160

angustus (N. & W.) VII, 163*

?bialveatus St. J. & W VII, 169*

?convexus St. J. & W VII.169*

?convolutus St. J. & W VII.165*

?exornatus St. J. & W VII.168*

? inflexus St. J. & W VII, 167*

" . ?keokuk St. J. & W VII, 169*

sancti-ludovici St. J. & W VII, 161*

Deltodus Newberry and Worthen 11,95,102,105; IV, 362, 364, 306, 370; VII.61, 141, 144,158

alatus N. & W IV, 368*

( " angularis N. & W.) ' 11,97*; VII, 177, 192*

( " ) angustus N. & W IV.368*; VII, 163

cinctulus St. J. & W VII, 146*

cingulatus N. & W 11,96,99*: VII, PL ix.flg. 13*,147,155

( " ) complanatus N. & W 11,98*; IV, PL iii.flg. 5*; VII, 184*

GENERAL INDEX. 97

Deltodus fasciatus N. & W IV.366*

( " grandis X. & W.). VI1.184*

intermedius St. J. & W VII, 153*

latior St. J. & W VII.145*

littoni N. & W IV.367*; VII.144,149

mercurii Newb VII, 144, 145

occidentals (Leidy?) YII.150*

parvus St. J. & W YII.151*

powelli St. J. & W VII.154*

propinauus St. J. &W VII.156*

rhomboideus X. & W 11,100*; IV.368; Vn,188*

sandalinus Eon * VII, 144

spatulatus N. & W IV.P1. Ill.fig. 11*,368; VII, 144, 148,166

stellatus N. & W 11,97*; IV.367; VII.144,150

sublams Ag VII, 144

trilobus St. J. & W VII.148*

undulatus N. & W 11,96,98*; IV, SOT; VII, 144, 147

Deltopty.-hius Agassiz VII, 61, 81, 89

acutus Ag VII.91

expansus St. J. & W VII, 85, 98*

nitidus (Leidy) VII, 91, 99*

" . primas St. J. & W VII, 93*

varsoviensis St. J. & W VII, 96*

wachsmuthi St. J. & W VII, 93*

Dendrerpeton Owen II, 140

Dendricopora deKoninck VIII.359

Dendrecrinus Hall 11,181; 111,333

latibrachiatus Bill 111,334

osvegoensis M. & W III,333t*

proboscidatus Bill 111,326

Dentalium Linnaeus 11,284; V.589; Vn,325; VIII, 145

annulostriatum 31. & W ...". V.589*

antiquum Goldf 11,284

illinoiense Worthen VIL325; VEH.145*

meekanum Gein V.590*

missouriense Swallow V 11, 325

primarium Hall 11,284

priscum Munster < 11,284

venustum M. & W 11,284*

Dcsmacanthus Meek and Worthen Ill, 565

Desmiodus St. John and Worthen VI, 387,403; VH.65

costeiliferus St. J. & W VI,341*,343

" (?) flabellum St. J. & W VI, 343*

" (?) ligoniformis St. J. & W VI, 342*. 344

minusculus (X. & W) VI, 839. 342

tumidus St. J. & W VI, 299, 339*, 342

Dexiobia Winchell II, 157

ovate (Hall) H, 157

Diamesopora Hall Vni.380,467

communis Ulrich VIH.469*

constricte (Hall) VIII, 468

dichotoma Hall VIII.381,467

infrequens (Hall) VIII. 467

oscula (Hall) VIII, 467

ow'.-ui (James) VIII, 467

subimbricata (Hall) . . . . , VIII, 467

—13

98 GENERAL INDEX.

Diamesopora tubulosa (Hall) VIII, 467

varia (Hall) VIII, 467

vaupeli Ulrich VIII, 468*

venusta (Hall) VIII.468

Dichocrimis Munster 11,167.171.203,280: V, 440,500,537; VI,515; VII.313; VIII.190

( " ) chesterensis M. & W 11,292

constrictus M. & W II, 263*

conus M. & W 11.169*

cornigerus Shutn. (?) V.537*

coxanus Worthen VII.313*

( " )crassus M. &W 11,290

(?) elonga'us Austin 11,168

expansus M. & W V, 500*

ficus C. & L V.502*; VI, 515*; VII.313

fusiformis C. & L 11,168

hamiltonensis Worthen VII, 313*

inornatus W. & Sp VIII, 172, 187, 190*

intermedius Kon. & Leh 11,170

laevis Hall 11,170

lineatus M. & W. V.440*

ovatus O. & S V.441; VIII, 190

pisumM. & W V.441*

pocillum Hall 11,168

sexlobatus Shum 11,290

simplex Shum 11,264 ; VIII, 190

stelliformis M. & W V.502

striatus O. & 8 V.441

sp. indet VIII.162

Dichotrypa Ulrich VIII, 386,498

elegans Ukich VIII, 500*

expatiata Ulrich VIII, 501

flabellum (Rominger) VIII, 501*

foliate Ulrich VIII, 386, 499*

grandis Ulrich VIII, 498*

internodia Ukich < .VIII, 500*

lyroides Ulrich VIII, 502*

Dicranopora Ulrich VIII.338

internodia Miller and Dyer VIII, 389

Dictyophytum Hall VIII, 216, 218, 236

abacus Hall VIII, 236

annulatum Hall VIII.236

baculum Hall VIII, 236

cinctum Hall VIII.236

conradi Hall VIII, 236

cylindricum Whitlield VIII, 236

fenestratum Hall VIII.236

fllitextile Hall VIII, 236

hamiltoneuse Hall VIII.236

irregulare Hall VIII.236

nodosum Hall VIII, 236

parallelum Hall VIII, 236

patulumHall VIII, 236

prismaticum Hall VIII, 236

" (?) redfleldi Hall VIII, 236

rude Hall VIII, 237

sacculus Hall... VIII, 237

GENERAL INDEX. 99

Dictyophytum telum Hall VIII,237

tenue Hall VIII, 237

" tuberosum Conrad VIII,237

Dictyospongidae Hall VHI.236

(Didymopoi a Dlrich) . VIII.382

Dlmyleus Agassiz VII, 200

Diploclema Ulrich VIII, 368

sparsum (Hall) VIII.369*

trentonense Ulrich VIII, 369*

Diplodus Agassiz 11,59

compre^sus Newb 11,60*

( " ) duplicates N. £ W n,61*; VI.289

gibbosus Ag 11,59,61

gracilis Newb 11,59,61

( " Hncurvus N. & \V 11,62*; YI.289

latus Newb II, 59*

minutus Ag 11,61

Diplopora Young and Youug VIII.358,398,636

bifurcata Ulrich VIII.637*

biserialis Ulrich VIII, 637*

marginalis Young and Young VTH,398,637

simplex (Vine) VHI, 636

(Diplopoi Mae Tine) VIIL359

Diplotrypa Nicholson VIII, 378, 418, 457

• ' ? dubia Ulrich VIH,379, 459*

inflda Ulrich Vjn,378,457

milled Ulrich VIH,378,457

patella Ulrich VIII,458*

petropolitana (Pander) VIII, 378, 379, 458

regularis Foord VIII, 457, 458

westoni Ulrich VIII.378

whiteavsi Nicholson VIII, 457

Diplotrypidas Ulrich VIII, 342, 378

Dipriacanthus McCoy VI, 47:.', 475

Dipterus Sedgwick and Murchison VI, 329

Discina Lamarck V.572; VHI.102

nitida (Phillips ?) V.572*

varsoviensis Worthen VIII,102*

Discites McCoy II, 161

disciformis M. & W V.522: VI.531

highlandensis Worthen VI, 531*

( ' ' tuberculatus Owen) 11,386,388

Sby 11,388

Discopora squamata (Lonsdale) VIII, 469, 471

Discotrypa Ulrich VIII, 378

elegans Ulrich VIII.378

(Discus) digonus M. & W 11,163*

( " ) planorbiformis M. & W 11,386

( ' ' ) sangamonensis M. & W 11,386

( " ) trisulcatus M. & W 11,162

Disteganopora d'Orbigny VIII, 345

Dithyrocaris Scouler V.618

carbonarius M. & W V, 618*

colei Portlock V,619

s -ouleri McCoy V, 619

Dittopora Dybowsk v VIII.340

100 GENERAL INDEX.

Dolabra McCoy 111,339

" (?) alpina Hall 11,346

" amygdalina (Phill) 111,340

angustata (Sby.) 111,340

" hindi (Bill.) 111,339

orbicularis McCoy VIII.109

sterlingensis M. & W III,v339*

" unilateralis (Sby.) 111,340

Domopora d'Orbigny VIII, 340

Dorycrinus Eoemer 11,209,213,290; V, 379; VI.513; VIII, 100, 173

canaliculatus M. & W V,381*

concavus M. & W II,215*t; V1II.177

cornigerus (Hall) V.380

'desideratus (Hall) V.380

divaricatus (Hall) V, 380

gouldi (Hall) V.380

helice (Hall) VIII, 176

immaturus W. & Sp VIII, 174, 175*,176

kelloggi Worthen VI.513*

mississippiensis Eoem V.380,385; VIII, 100*

missouriensis (Shum.) V, 380, 384

parvibasis W. & Sp , VIII.177*

duinauelobus (Hall). '. V, 380,385

var. intermedius M. X W V, 385*

radiatus W. & Sp VIII,176*

roemeri M. & W V.383*

subaculeatus (Hall) V, 380

subturbinatus M. & W... 11,212*; V.380

symmetrieus (Hall) V.380

trinodus (Hall) V.380

unicornis (O. & 8.) V.380,383*

. " unispinus Hall V.380

Drepanacanthus Newberry and Worthen 11,120; VI, 447, 460,456,459; VII.253

( " )anceps N. & VV 11,122*; VI.458

gemmatus N. & W II.123M25; VII, 253

reversus St. J. & W VI.456*; VII.253*

( " ' Jstellatus N. & W 11,125*; VI.4C8

Drymotrypa Ulrich VIII, 399, 607

cisseis (Hall) VIII, 399

dichotoma Ulrich VIII, 399*

diffusa (Hall) VIII, 399*

niagarensis (Hall) VIII, 607

Dystactospongia Miller VI1I.212, 217,239,255,277

insolens Mill VIII, 239

minima Ulr VIII,239

minor U. & E t VIII,239,278*

rudis U. & E V1II,239,279*

Eatonia Hall Ill, 395

peculiaris (Conr.) Ill, 395*

Echinocrinus Agassiz 11,294

Echinodermata II, 117. 107, 234,263, 288; 111,291,321,317,370.421,463,511;

V, 323, 530, 546,561; VI, 492,501, 510,526; VII, 269, 367, 341; VIII, 83, 157

Echinodiscus Worthen and Miller VII, 335

optatus W. & M VII.336*

Echinothuridje VII, 331

GENERAL INDEX. lOl

Echinoidea II, 225.247,294

Echinus drydenensts Vanuiem V.482

Ectenodictya Hall VIII, 237

burlingtonensis Hall VIII.237

excentrica Hall Vni,237

expansa Hall VIII.237

implexa Hall VIH.237

Edestes Leidy II. 84

heinrichsi N. & W IV, 350*; VI.461

minor Newb 11,84*

vorax Leidy IV, PL I, fig. 2*,a50

Edmondia Koninck II, 346 ; V.583 ; VIII.121

" (?) compressa McCoy V.583

illinoiensis Worthen VIII, 122*

ovata V.PL XXVI, fig. 13*

peroblonga M. & W V, 583*

( " ) radiata Hall V.58!

unionilormis (Phill?) 11,364*

varsoviensis Worthen VIII, 121*

Edriocrinus HaU 111,370

pociUiformis Hall 111,370*

Edriospongia Ulrica and Everett VIII, 217, 222, 235, 271

basalis U. & E Vm,235, 272*

Edwardsocrinus d'Orbigny *. . .11,170,172

Elaeacrinus Roemer 11,275 ; VII, 357

angularis (Lyon) VII, 360

elegans Conr VII.362

lucina (Hall) VII.360

melonlf ormis Barris VII, 361

( " )norwoodi O. & S 11,275; 111,496; VH,359

obovatus Barris VII, 3581

verneuili Troost VH.362

(Elonichthys) peltigerus Newb 11,17

(Encrinus moniliformis Miller) n,315

Endocycliiiues Desor , II, 226

Endolobus Meek and Worthen ., II, 307

( " peramplus .M. & W.) 11,308*

spectabilis M. & W 11,308*

Entalophora Lamarck VIII.337

Entalophoridae Reuss VIII, 368

Entolium Meek V.558

aviculatum (Swall.) 111,455; V.588*

Entomostraca (11,393); 111,299,320,363,390,416, 447, 460,5iO; V, 525,612; VI, 497,508

(Entomostracites) crassicauda Wahlenberg 111,322

Eocidaris Desor 11,294 ; V.478

(?) squamosus M. & W V.478*

Eocoryne Matthew VIII, 240

gemina Matthew VIH.-240

Eoscorpius Meek and Worthen 111,560

carbonarius M. & W 111,5601,564,508

Eospongia Billings VIII, 211, 217, 234

roemeri Bill VIH.234

varians Bill VIII, 234

Ephemeridas in, 571

Ephemerites Scudder 111,571

afflnis Scud Ill, 572t

102 GENERAL INDEX.

Ephemerites gigas Scud Ill, 571t

simplex Scud Ill, 571t

Epilampridse 111,568

Eretmocrinus Lyon and Casseday V.468; VII.306; VIII.173,174

calyculoides (Hall) V.368

(?) carica (Hall) V.368

claelia (Hall) V.368

clio (Hall) V,368,378

(?) corbulus (Hall) V, 368

coronatus (Hall) V.P1. X.flg. 8*

(?)dodecadactylus M. & W 11,205*; V.368

(?) gemmiformis (Hall) V, 368

(?)hazeri (M. Ch.) V.368

magniflcus L. & C V,368

matula (Hall) V.368

neglectus M. & W V.377*

(?) oblatus (Hall) V, 368

remibrachiatus (Hall) V, 368

(?) sinuosus (Hall) V,368

(?) urniformis (M. Ch.) V.368

varsoviensis Worthen VII, 306*

verneuilanus (Shum.) V,368,37!»*

Eridopora Ulrich ¥111,382,463

huronensis (Nich.) VIII, 463

macrostoma Ulrich : .VIII, 382

Erismacanthus McCoy VI, 401

jonesi McCoy VI, 463

mac-coyanus St. J. & W VI, 461*

Erisocrinus Meek and Worthen II, 315 ; V, 445,561

antiquus M. & W V, 4 *7*

conoideus M. & W II, 318t

( " nebrascensis M. & W.) 11,317; Ar, 445,446

( " ) tuberculatus M. & W 11,319: V,446

typus M. & W II,317t,318+; V,445,561*

whitei M. & W V.448*

Eschara argyrias d'Orbigny VIII, 330t

artemis d'Orbigny VIII, 330t

EscharidaB VIII, 361,366

(Escharopora Hall) VIII, 390

( " ) nodosa Hall VIII, 304

Ethmophyllum Meek VIII, 212, 216,240

minganense (Bill.) VIII, 240

profundum (Bill.) VIII,240

rarum (Ford) VIII.240

rensselzericum (Ford) VIII, 240

whitneyi Meek VIII, 240

Eucalyptocrinus Goldfuss VI.501

magnus Worthen VI, 501*

sp. indet VI, PL xxiv.flg. 2*

Euchrysalis Laube 111,362

fusiformis (Munster) 111,362

(Eulima) peraeuta M. & W II, 375

Eulimidae 111,362

Eumicrotis Meek 11.258, 336

hawni Meek 11,338

var. sinuata M. & W ' 11,338*

' ' speluncaria King 11,339

GENERAL INDEX. 103

Eunema Salter 11,380

( " ) salteri M. & W 11,381

Eunemacanthus St. John and VTorthen VII, 246

costatus (N. & W.) Til, 246*

Euomphalus Sowerby 11,158

catillus Sby 11,158

discors Sby 11.158

)lens Hall 11,159

nodosus Sby II. 158

pentangulatus Sby II. 158

pernodosus M. & W y. 604*

) planidorsatus M. & W n, 302*

rugosus Sby 11,158

subquadratus M. & W y . 607*

< " sp.) 111,313

Eupachycrinus Meek and Worthen 11,175.177; V, 554. 5»r>: VI..VJ7; VII. 311; Vin,97

asperatus Worthen y II, 311*

basetti Worthen VI. 528*

boydi M. & W V.554*; VII, PI. xxix.fig. 3*

craigi Worthen VI, 527*

fayettensis Worthen V.565*; VI.. ".27

formosus Worthen VH.312

monroensis Worthen VII, 312*

orbicularis (Hall) 11,178; Vin,97*

pentalobus (Hall) II, 1 8

quatuordecim-brachiatus (Lyon) Vn,312

(?) sancti-ludovici Worthen VIII, 98

subtumidus M. &W 11,178

tuberculatus M. & W V.566*

(?) verrucosus (Wh. & St. J.) YI.528

Eui-hoberia Meek and Worthen 111,556

armigera M. & W in, 556t

" (??) major M. & W 111,558+

Euproops Meek 111,547

danae M. & W m,547t

Euretidae Zittel VIII, 22

Eurydictya Ulrich VIII, 389, 492, 520

calhounensis Ulrieh VIII, 520*

montifera Ulrk-h VIII, 389, 521*

multipora Hall , Vni,521.522

sterlingensis Uhrich VH1, 522*

Eurylepis minuta Ne\vb IV, 348

Eurypterus DeKay 111,544

( " )ferox Salter 111,559

mazonensis DeKay Ill, 544f

remipes DeKay . 111,546

Euspilopora Ulrich VIII, 389,526

:rrisi Ulrieh VIII. 527*

palmipes (Hall; VIII. 527

serrata Ulrich VIII. 390, 526*

Evactinopora Meek and Worthen Ill, 501 ; \ III, 387,508

grandi^ M. & W III.503t*; VIH.511*

quinqueradiata U!r VIII, 510*

radiata M. & W 111,502+*: VIII, 387.509*

sexradiata M. & W III. 502*: VIII, 510*

(Exogyroceras Meek and Worthen) 111,509

104 GENERAL INDEX.

Fasciolaria Lamarck 11,383

(Favieella Hall) VIII.384

Favosites Lamarck HI, 408

{ " hemisphaericus Kuborga) 111,304

( " lycopodites Vanux.) 111,304

( " ) petropolitanus Pander 111,304

Favositidse VIII.436

Fenestella Lonsdale 111,504; VIII,350,359,395,535

( " JacmeaHall VIII(355,534

( " ?)ambigua Hall VIII,534,679

bellistriata Hall ¥111,331*

bigeneris Ulr VIII.355

burlingtonensis Ulrich VIII, 536*

cestriensis Ulrich VIIL547*

cingulata Ulrich VIII, 543*

compressa Ulrich VIII, 539*

var. nododorsalis Ulrich VIII, 540*

conradi Ulrich VIII, 553*

(Polypora) cultcllata Hall) VIII, 586

delicatula Ulrich VIII, 549*

elevatipora Ulrich VIII, 549*

exigua Ulrich VIII, 545*

fenestrata Y. & Y VIII.352

filistriata Ulrich VIII, 535*

flexuosa Uh-ich VIII, 548*

funicula Ulrich VIII.542*

( ' ' hemitrypa Prout) VIII, 560*

imeaualis Ulrich VIII.554*

limitaris Ulrich VIII.538*

membranacea Phill VIII.353

mimica Ulrich VIII, 552*

modesta Ulrich VIII, 550*

multispinosa Ulrich VIII, 540*

nodosa Prout VIII.535

( " ) perrnarginata Hall VIII.556

perminuta Ulrich VIII, 551*

plebeia McCoy VIII, 395,537

( " )plumosa Prout VIH.561,662

prc-ecursor Hall VIII,355,534

prisca Lonsdale VIII.353

auadrulaHall VIII.534

regalis Ulrich VIII.538*

reteporata Shrubsole VIII, 544

retrorsa M. & W 111,504*

rudis Uh-ich VIII, 537*

( " ) semirotunda Hall VIII, 556

serratula Ulrich VIII, 544*

sevillensis Ulrich VIII, 552*

subquadrans Hal! Ill, 504

tenax Ulrich VIII, 546*

( " )thyene Hall VII1.534

triserialis Ulrich VIII, 541*

veraUhich VIII, 535*

wortheni Ulrich VIII, 551*

Feuestellidre King VIII,349,351t,395

GENERAL INDEX. 105

(Fenestellinae Waagen and Pichl) VIII. 359

Fenestralia Prout VIII, 359, 396,604

sancti-ludovici Prout VIII. 604.396

var. compaeta Ulrich VIII, 605*

Fenestrapora Hall VIII, 395 ,557

biperforata Hall Vin,395,558

occidentalis Ulrich Vin, 558*

Fishes 11,1; IV.355; VI.245; VH.55

Fissodus St. John and Worthen VI, 413

bifldus St. J. & W VI,414»

tricuspidatus St. J. & W. ... VI, 415*

Fissurellidae HI, 386

Fistulata VTTT, 193

Fistulipora McCoy VLU.,382. 474

asteria (Prout) Vin, 478

astrica Ulrich VU[,320t, 477*

?) clausa Ulrich VTn.485*

collina Uh-ieh V 111, 478*

communis Ulrich Vm,382,476*

compressa Rominger VJLU,488

(?Dichotrypa) corrugata Ulrich VJLLL.480*

elegans Rominger VH1.385

) flabellum Rominger Vill,498, 501*

foordi Ulrich VTH,315t ,479*

incrustans (Phillips) ¥111,382

) lunata Rominger Vin, 384, 489*

) minuta Rominger Vin. 427*. 476

minor McCoy) Vni.382,474

minor Nicholson) VIH,475

monticulata Ulrich VIH.477*

mucosa Nichol. and Foord V 111, 474

) peculiaris Rominger VEG, 386, 503*

proporoides Nicholson) Vin,386

( ) occidens Hall and tt'hitfleld VIII. 425

( " ) oweni James VIII, 467

spinuUfera Rominger VHI, 480*

stelUfera Rominger Vin, 481*

utricula Rominger VTU,477

Fistuliporidae Ulrich Vni.343,382,471, 482,504

Flustra palmata McCoy VUI.353

( ' ) spatulata Prout VIII, 670*

( " ) tuberculata Prout Vm,441*t,671

Foraminifera in,345; V.560; VI.500

Forbesiocrinus de Koninck and LeHon H, 242,268,270; HI, 495; V,399,4%

aggassizi Hall H.270; in, 495

var. giganteus M. & \V TTT, 495*

( ) asteriiformis Hall n,243; III,4!i4

( ) communis Hall 11,270

(?)diversus M. & W 111,495

giganteus(?) M. & W HI, 495*

) juvenis Hall 11,272

( ) kelloggi Hall 11,270

) meeki Hall H.243; V.553

) monroensis M. & W 11,243,244*

multibrachiatus L. & C V.498

nobilis Kon. & Leh II,27'j

-14

106 GENERAL INDEK.

(Forbesiocrinus) norwoodi M. & W 11,243. 245*

( " ) nuntius Hall 11,270

( " ) semiovatus M. & W 11,272*

( " ) thiemei Hall 11,271; V, 399*

( " ) whitfleldi Hall 11,243*; V.552*

wortheni Hall 11,270*; V,496*,553

FrondiporidrB Reuss VIII, 368

Fungia discoidea Gold! . . . . II, 420

Fuftulina Fischer V, 560

cylindriea Fisch VI, 526

var. ventricosa M. & W V.560

gracilis M e,fjk V.560*

ventrcosa M. & W V.560*

Galeocerdo Muller 11,79

GaleusCuvier 11,79

Gampsacanthus St. Jolin and Worthon VI, 471

(?)latus St. J. & W VI, 474*

sauamosus St. J. & W VI. 473*

typus St. J. & W VI.472*

Gampsonyx flmbriatus III. 552+

Ganoidea II, 135

Gasteropoda 11,158,200,284,302,351; 111,441,457,506: V,516,589; VI.495; VIII.135

Gasterosteus Linnaeu^ IV.371

Gecco Linnaeus 11,137

Geisaeantlms St. John and Worthen VI, 440 ; VII, 251

bullatus St. J. & W VI, 441*

stellatus St. J. & W VI.440*

Gervillia Cox II- 336

" auricula Stev 11,341

laminosa Phill 11,340

) longispina Cox 11,336

lunulata Phill 11,340

Gilbertsocrinus Phillips II.21V219: 111,476; V.389

bursa Phill II,217+,219

calcaratus Phill H.217+,219

(Goniasteroidocrinus) fl?cellus M. & W II, 219. 222*, 224+

mamillaris Phill 11,217,219

(Goniast.) obovatus M. & W V.391*

papillatus (Hall) 11,219

(Goniast.) reticulatus (Hall) 11.219

( " ) tenuiradiatus M. & W "V.389

( " ) tuberculosus (Hall) 11,225

( " ) tuberosus (L. & C.) 11,219,220+

( " ) typus (Hall) 11,219

Glauconome Munster (Goldfuss) VIII, 397, 566, 614, 615, 636

disticha Lonsdale VIII, 615

( ) elegans Young and Young VIII, 397

( (Dip:opora) ) marginalis Young and Young VIII, 636

( " ) triiineata Meek VIII, 620*

Gl«ssolega Bonap II, 137

(Glossotrypa Hall) VIII, 383

Glymmatacanthus St. John and Worthen VI, 446

irishi St. J. & W VI.447*; VII.250

petrodoides St. J. & W VII, 250*

rudis St. J. $ W ...VII.249*

GENERAL INDEX. 107

Glyptopora Ulrich Yin. 387,511

elegans (Prout) II, 413'; VIII;518*

keyserlingi (Prout) II, 413 ; VIII,3S-, 517*

megastoma Ulrich YIII.518*

michelini (Prout) 11,414*: Tin, 515*

pinnata Ulrich Yin, 516*

plumosa (Prout.) 11,414*; Yin,3,S7,512*

punctipora Ulrich Y III, 519*

sagenella (Prout) 11,415*; YIII,513*

var. caliculosa Ulrich YIII.514*

var. lata Ulrich YIII. 515*

Gomphoceras Sowerby Ill, 444

beta Hall 113,444

saccu'.us M. & W Ill, 445

(Apioceras) turb'niforme M. & W 111,444*

Gomphocystites Hall '. 111,315

Goniasteroidocrinus Lyon and Casseday 11,217, 219.2.>2; V,324,389

flscellus M. & W n,219,222*,22It: Y.390

obovatus M. & W Y.391*

papillatus (Hall) 11,219

reticul.itus (Hall) 11,219; V.390

tenuii adiatns M. & W Y.389*

tuberculosus Hall V.390,392

tuberosus L. & C II.2-.JOt; Y.324

(Trematocrinus) typus Hall) n,219; Y,325.390

Goniatites DeHaan 11,165,390; V.611; YIH.150

' ' chemungensis Yanuxem II, 166

compactus M. & W Y.611*

globulosus M. & W II,390t*,391t

( " hyas Hall) 11,165

iovensis M. & W 11,392*

lyoni M. & W 11,165*

mixolobus Phill 11,166

monroensis Worthen YIII, 150*

Goniocladia Etheridge, Jr YIII,360,3S7

(Goniocladinae Waagen and Pichl) YIII,360

(Goniocoelia Hall) 111,380

Goniotry pa Ulrich YIII, 3 89

bilateralis Ulrich VIII.389

Goniomya Agassiz 111,539

Goniophora sp. (?) VI. PI. XXIII. fig. 7*

(Gorgonia) aspera Hall YIII,639*

( " ) perantiqua Hall VIII, 405

( " ripisteria Goldf.) 11,423

Grammysia de Yerneuil in, 439

bisulcata (Conr.) 111,441

" (?) rhomboidalis M. & W 113,439

Granatocrinus (Troost) Hall 11,274; Dl,4%; Y.4G8.508.537; YH.349

cornutus (M. & W.) 11,276*

fimbriatus (?) M. & W 111,497

glaber M. & W ....Y.537*

granulosus M. & W V.508*

( )melo O. & S 11,275; III, 4%, 499; V II. 549

( " var.) projectus M. A: W UI.496+*

melonoides M. & W V, 46i*

neglectus M. & W V.471*

Granatocrinus norwoodi O. & S 11,275; 111,496*; V.473*; VII.350,359

pisum M. & W V.470*

projectus (M. & W.) 111,496+*, 498 (*?)

( " )sayi Shum 11,274; V.469; VII.350

shumardi M. & W 111,4981*

Graphiocrinus de Koninck and LeHon 11,181,186; V.559; VIII.193

dactylus Hall V.559*

longicirrifer W. & Sp VIII.193*

(?) planobrachiatus M. & W II, 241

quatuordecim-brachialis Lyon 11,177

spinibrachiatus (Hall) VIII, 193

wachsmuthi (M. & W.) VIII, 193

Graptodiotya Ulrich VIII.349, 393

perelegans Ulr VIII.393

Griffithides Portlock V.525

bufo M. & W V.528*

portlocki M. & W V,5*5*

scitula M. & W V.612*

" (?) sangamonensis M. & W V.615*

Gymnolaemata Allman VIII, 333,367

Gymnophidia 11,137

Gypidula (?) comis Owen Ill, 429

Gyracanthus Agassiz VII, 251

" (?) cordatus St. J. & W VII, 251*

Gyroceras de Koninck 111,446,459

constrictum M. & W 111,446; VI, PL XXVII, fig. 2*

gracile Hall 11,164

logani Meek Ill, 447

" (?) rockfordense M. & W Ill, 459*

Gyromices ammonia Goeppert 11,462

Hadrophyllum Edwards and Haime 111,420

Harpacodus Agassiz : VI.348,354

compactus St. J. & W VI, 355*

( ' ' dentatus Ag.) VI.354

occidentalis St. J. & W VL355*

Hederella Hall VIII, 3(58

Helicina occulta VIII, 15

Helicopora Claypole VIII, 359, 396, 580

( " archimediformis Claypole) VIII,580,P1. JLXIII.flg. 15*

latispiralis Claypole VIII, 396,580

Heliotrypa Ulrich VIII,366,404

bifolia Ulrich VIII, 308t, 404

Heliotrypid* Ulrich (provisional) VIII.366,404

Helodus Agassiz 11,52,74,90,111; iv!359,365; VI.337; VII.64,124

( " angularis N. & W.) VI, 346. 362

angulatus N. & W 11,83*

biformis N. & W 11,77*: VI, 419

carbonarius N. & W 11,75*

( " )compressus N. & W 11,78*; IV.360*; VI.287*

coniculus N. & W II, 75*

consolidate N. & W 11,87*; IV.360; VII.124

crenulatus N. & W 11,82*

dens-humanus N. & W 11,76*

( " ) denticulatus N. & W 11,80,81*; VI.317,345

( " )didymus Ag 11,75; VII.73

elytra N. & W 11,78*; VII.95

GENERAL INDEX.

Helodus gibberulus Ag ...11,79

( )gibbosus N. & VT : «. 11,79*: VI, 305

laevissimus Ag 11.91

Umax N. & W II, go*, 83

(Cochliodus) nobilis N. & W H, 88*

( ) placenta N. & W 11,80*; VII, 69*

planus Ag 11,80,93; TI.419; TII.64

politus X. & W 11,79*

pusillus (McCoy) 11,34

rugosus N. & W IV. 359*

sulcatus N. & W 11,83*

undulatus N. & W 11,82*

Helopora Hall Till, 363, 401, 642

circe Billings VIII,46*

( ) concava Billings Vm,645

( ) formosa Billings YIII.645

fragilis Hall VILE, 401, 643t

imbricata Ulrich Till, 644*

lindstromi Ulrich Till. 643t

( " ) lineata Billings Tin, 645

( " ) lineipora Billings Till, 645

spiniformis Ulrich Till, 644

( " ) striatapora Billings Till, 645

( " ) strigosa Billings Tm,645

( " ) variopora Billings Till, 468

Hemeristia Dana 111,566

occidentalis Dana 111,566

Hemipronites Pander 111,349; T.570

crassus M. & Hayd T.570

crenistria Phill Ill, 411

(?) propinauus M. & W 111,351

suplanus (Conr.) Ill, 349*. 351

Hemipristis Agassiz I V, 351

Hemitrypa Phillips Till, 353, 396,559

aspera Ulrich Till, 563 *

nodosa Ulrich Till, 562*

oculata Phillips Till, 396

pateriformis Ulrich Till, 564*

perstriata Ulrich Till, 564*

plumosa (Prout) Till, 561, 562.564

proutana Ulrich Till, 560*

var. nodulosa Ulrich Till, 562*

var. vermifera Ulrich Till, 561*

tenera Ulrich Till, 559

Hernodia Hall Tin, 368

Heterocrinus Hall HI, 324, 328 ; TI, 4H3

crassus M. & W 111,324*; TI.493

( " )incurvus M. & W IH,327i*

subcrassus M. & W Ill, 325*

(Heterodictya Nicholson) Till, 390

Heteropora Blainville Tin,340

Heteroschisma Wachsmuth Til, 352

alternatum (Lyon) Til, 357

var. elongatum Wachsmuth Til, 353

gracile Wachsm Til, 354t

110 GENERAL INDEX.

Heterospongia Ulrich VIII,212,215,217,239

aspera Ulr VIII, 239

knotti Ulr VIII.239

subramosa Ulr VIII, 239

Heterotrypa Nicholson VIII,S71,413

frondosa d'Orbigny VIII, 37 1,413, 414

inflecta Ulrich VIII, 414*

mammulata d'Orbigny VIII, 413

( " mammulata Nicholson) VIII, 413

proliflca Ulrich VIII.413*

singularis Ulrich VIII, 415*

( " ) trentonensis Nicholson VIII, 433

( " )vaupeli Ulrich VIII. 413, 421

Heterotrypidae Ulrich VIII, 339, 371

Hexacrinus Austin II, 168,173

HexactinellMa Schmidt VIII, 220,236

Hindia Duncan VIII, 226,231,255

" inagqualis U. & E VIII, 229, 234, 27 5*

' ' inornata Hall VIII, 228

' ' parva Ulr VIII, 229, 232, 234

' ' sphaeroidalis Duncan VIII,217,225*,234

Hipponyx Defrance Ill, 386

Holasterella Carter VIII, 218

(Holopea) depressa M. & W 111,443

Holoptychius Agassiz II, 19

Homacanthus Agassiz 11,113

arcuatus Ag 11,114

( " ) gibbosus N. & W 11,113*; VI.464

macrodus McCoy II, 115

( " ) rectus N. & W 11,115*; VI, 466*

Homocrinus Hall VI, 492

angustatus M. & "W VI, 492*

parvus Hall II, 182

polydactylus Shum VI.493

(?) scoparius Hall 111,347

Homotrypa Ulrich VIII, 370, 409

" arbuscula Ulr 409*

curvata Ulr VIII, 371

dawsoni (Nich.) VIII.410

flabellaris Ulr VIII, 411*

gelasinosa Ulr VIII, 410*

Homotrypella Ulrich VII 1, 370, 412

contexta Ulr VIII, 412*, 416

instabilis Ulr VIII.370

(Hornera?) dichotoma Hall VIII.607

Hyalostelia Zittel VIII,217,232, 238,246

delicatula Ulr VIII, 238, 246t

metissica Dawson VIII.238

solivaga Ulr VIII, 232*, 238

Hybechinus Worthen and Miller VII, 331

spectabilis W. & M VII, 332*

Hybocladodus St. John and Worthen VI, 284, 291

compressas ( N. & W.) VI,287*,289

intermedius St. J. & W VI, 287*

nitidus St. J. & W VI, 288*

plicatilis St. J. & W VI,286*,288

tenuicostatus St. J. & W ...VI.286*

GENERAL INDEX. Ill

Hybocrinus Billings III.327

" (?) incurvus M. & ^W 111,327+*

Hybodontiflae 11,70,91 ; VI.251 ,284,313

Hy boclus Agassiz 11,121 ; VL285

plicatilis Ag VI.285

reticulatus Ag YI.291

Hydnoceras Com ad Vin,216

Hydreionocrinus de Koninck 11,181

(?) verrucosus Wh. & St. J VI.528

woodianus Kon 11,177

Hylonomus Dawson 11,137

Hvolithes Eiclrwald. . . '. VIII, 455

Hyphasmopora R. Etheridge, Jr VIII, 366

Hystricospongia Ulrica VHI.233, 245

carbonaria Ulr VIII, 218,233, 245*,246t

lanthina Bolten II, 362

lanthinopsis Meek and Worthen 11,362

Ichthyocrinidae Yni,197

Ichthyodorulites 11,113; IV, 370; VI, 487; VII, 233

Ichthyorachis McCoy VHI,398

Idiotrypa Ulrich VHI.375*

parasitica Ulr Vm,375

Idmonea Lamouroux V11I.608

serpens Linnaeus Yin, 330+

Igoceras Hall 111,387

plicatum (Conr.) 111,387

Illaenus Dalman in,320; VI.508

' ' americanus Bill in, 320

(Bumastus) barriensis Murch VI.509

crassicauda (Wahlenb.) 111,322*

(Bumastus) graftonensis M. & W VI, 508*

insignis Hall VI, 510

salteri Barrande VI, 510

" taurus Hall IH,320*

trentonensis Emm HI, 322

(Bumastus) sp. indet VI, PI. XXIV.flg. 3*

Inaduna'a VIH.193

Insecta II, 410 ; III, 566

Intrapora Hall VIII, 349, 394, 532

cosciniformis (Nicholson) VIII, 532*

puteolata Hall VIII.394,532

(Intricaiia) clathrata Miller and Dyer VIII, 639

( " ) reticulata Hall VIII, 639

Inversaiia Hagenow 11,417

Ischadites Murchison VIH, 238

Isocardia Lamarck 11,346

( " ) unioniformis Phill 11,346*

Isocrinus Phillips 11,268

Isogramma Meek and Worthen V.568

millepuncta-a M. & W V. 566*

Isonema Meek and Worthen Ill, 442

depressumM. & W III,443t*

bellatulum (Hal!) IH.443

Isopoda II,o99 ; III, 549

Isotelus DeKay VI, 497

megistos Locke VI.498

" vigilans M. & W VI, 497*

112 GENERAL INDEX.

IsotrypaHall (emended) VIII.353,395,534,679

ambigua (Hall) VIII, 534

conjunctiva Hall VIII, 395

gothlandica Ulrich VIII.395, 678*

(Jerea excavata d'Orbigny) VI, 499

Jerieca Zittel ' VIII.226

(Keratophytes) dubius Schlotheim VIII, 606

Labodus Agassiz VII, 200, 228, 231

" planus Ag VII, 228

prototypus Ag VII.228,231

Labyrintodontia 11,137

Lacertilia II, 135

Lambdodus St. John and Worthen VI,280

calceolus St. J. & W VI.281*

var. robustus St. J. & W VI,282*,283

costatus St. J. & W VI.280*, 283,284

hamulus St. J. & W VI, 283*

reflexus St. J. & W VI.284*

transversus St. J. & W VI,282*,284

Lamellibranchiata 11,156,231,256,281,300,326;

111,294,306,337,354,437,453,532; V.539,573; VI,494,511, 524.529; VII, 319,326; VIII.107

Lamna Cuvier .' 11,30

sp. (in the drift) VIII, 4+

Lasiocladia Hinde VIII,218,233

compressa Hinde VIII.233,249

hindei Ulr VIII,233,249

Leaia Jones HI, 541

' ' leidyi Lea Ill, 542

" var. salteriana Jones 111,542

" williamsoniana Jones 111,532

" tricarinata M. & W III,5iOt,541

Lecracanthus St. John and Worthen VI, 473, 475

unguiculus St. J. & W VI.476*

Lecythiocrinus White VII, 317

adamsi Worthen VII, 317*

Leda Schumacher 11,282

( " )curta M. & W 11.283*

( " Hevistriata M. & W 11,282

( " )subscitula M. & Hayd 11,283

Lepetopsis Whitfi eld VIII, 140

chesterensis Worthen VIII, 140*

LepideehinidJB 11,229; VII.331

Lepidechinus Hall 11,226,229,294; 111,522; V.481; VII.334

imbricatus Hall 111,522

rarispinus Hall 111,522; V.481

Lepidesthes Meek and Worthen Ill, 522 ; VII.331

coreyi M. & W 111,524+ , 525

Lepidolites Ulrich VIII.212,217,239

dickhauti Ulr VIII. 239

elongatus Ulr . VIII, 239

Lepidoptera (?) 11,410

Leptacanthus Agassiz 11,113, 116

( ) jenkinsoni McCoy 11,117; VI, 433

( J junceus McCoy 11,117; VI, 433

( " }) occidental N. & W VI,433; VII.238*

GENERAL INDEX. 113

Leptfena Dalman 111,393

( " depressa Kon.) ~. 111,426

( " distorta J. Sby m,426

( ' ' laticosta Yern.) HI, 427

( " nodulosa Phill in, 426

" (?) nucleata HaU m.393

" (?) rhomboidalls ( Wilkms) HI, 337

( " rugosa Hisinger) 111,426

( " ) subplana Conr 111,349

( " tenuistriata Sby.) 111,426

" (?) unicostata M. & W ni,337

teptocoelia Hall in, 397

flabellites (Conr.) 111,397*

( " )imbricata HaU 111,381

( " propria Hall) 111,397

Leptodomus McCoy 111,357 ; Vm.107

(?) magnus Worthen VHI.IOT*

(Leptogonia rugosa McCoy) in, 426

( " multirugata McCoy) IU.426

Leptomitus Walcott. VHI, 212, 216, 233

zittell Wale Vm,216,233

Leptopoterium UMch VIH,212,217.239

mammiferum Ulr VHI,239

Leptotrypa Ulrich Vni,377,455

flliosa (d'Orbigny) vm,456*

hexagonalis Ulr Vin,455*

minima Ulr Vni,378

semipilaris Ulr VHI, 457*

stidhami Ulr Vin,456*

Lichas Dalman HI, 299 ; TI, 508

" boltoni (Bigsby) HI.SOO; VI.508*

var. occidentalis Hall VI.508

" cucuUus M. & W DI,299*,PL i, flg. 6*

" hibernicus Portl m,300

trentonensis (Conr.) HI, 300

(Lichenalia Hall) VIII,382,475

( " -) concentrica Hall Vin,475

( * ' lunata Hall) VIII, 489*

Liehenotrypa Ulrich VUI, 383

cavernosa Ulr VIII, 383

Lima Bruguiere V.588; VIU.120

" chesterensis Worthen VUI,120*

' ' retifera Slium V, 588*

(Limulus) anthrax Prestwich 11,398

( " ) rotundatus Prestw U.394

Lingula Bruguiere m,305,437; V.572; VUI, 104

concentrica Conrad IU.437

granulata Phill in,3C6

" lewisi Sby in,306

mytiloides Sby V.572*; Vffl, 105

quadrata Eichw ." Ill, 305*

spatulata HaU in, 437

" subspatulata M. & W UI.437*

tenuigranulata McCoy % 111,306

varsoviensis Worthen Vni, 104*

-15

114 GENERAL INDEX.

Lioclema Ulrich VIII, 376, 425

araneum Ulr ¥111,431*

asperum (Hall) VIII, 416,425

cellulosum (Hall) VIII.425

foliatum Ulr VIII, :jX)lt , 431

floridum (Hall) VIII. 416, 435

gracillimum Ulr VIII.429*

? laminatum (Hall) - VIII, 416, 425

minutum (Eominger ?) VIII, 427*

ocoidens (Hall and Whitfleld) VIII.426*

parasitif-um (Hall) VIII, 425

ponderosum (Hall) VIII, 425

punctatum (Hall) -. VIII.376,430*

singulare (Hall) VIII.425

subglobosum Ulr VIII, 428*

wachsmuthi Ulr VIII.428*

? wilmingtonense Ulr VIII, 426*

Liodus St. John and Worthen VI, 335

" calcaratus St.'j. & W VI, 336*

grossipunctatus St. J. & W VI, 837

Lisgodus St. John and Worthen VI, 363

curtus St. J. & W VI, 364*

selluliformis St. J. & W VI.364,366*

serratus St. J. & W VI,365*,367

Listracanthus Newberry and Worthen IV, 371

hystrix N. & W IV.372*

Lithistidae Schmidt. VIII.220.234

Lithophaga Lamarck 111,536

lingualis (Phill.) 111,536*; V.539

" (?) pertenuis M. & W V.539*

Lituites Breynius VI.507

" ammonius Conr VI.507

graftonensis M. & W VI.507*

" marshi Hall VI, 507

Litorina Ferussac .- 11,364

( " ) biserialis Phill 11,364

( " ) wheeled Swall 11,364; V, 595

Loculipora Hall (Bominger M.S.) VIII.397

Lodanella mira Kayser VIII.218

Lophodus Romanowsky VI, 311

( " Newberry and Worthen) IV.360; VI,311

(Helodus) didymus Ag VII, 73

variabilis N. & W IV,359,361*; VI.317

Lophophyllum Edwards and Haime V.560; VIII, 79

profundum Worthen VIII, 79*

proliferum (M. Ch.) V.560*

Loxonoma Phillips 11,368,373,377,383; 111,442; V.596; VIII.139

bellatulum Hall ." 111,442

cerithiiforme M. & W VIII.139

" (?) compactum Hall : 11,377

halli N. & P 11,376

( " ) inornatum M. & W * 11,374*

( " ) minutum Stevens V.594*

multicostatum M. & W II, 378*

( " ) newberryi Stevens V.594*

( •' ) nitidulum M. & W ., 11,374*

" (?) obtusum Hall % 11.377

GENERAL INDEX. 115

Loxonema peoriense Worthen VIII, 139*

quadricarinatunT Worthen VIII, 140*

rugosum M. & W 11,378*

scalaroideum (Phill.) 11,379

scitulum M. & W 11,377*

semicostatmn Meek V.596*

sp. indet V, PL xxix, flg. 3*

(Michelina) sp. indet V.PL xxix.flg. 4*

Lumilites dactylioides Ow 111,345

Lyrodictya Hall VIII, 237

romlngeri Hall VEH.237

Lyropora Hall 111,504 ; Vni,396,580

divergens Ulr VTII,584*

( " lyra Hall) Vni,582,583

ovalis Ulr VIII, 585*

quincuncialis Hall VHI.396, 583*

ranosculum Ulr VIII, 581*

retrorsa M. & W 111,504*; VHI.SSl

subquadrans Hall 111,504; Vin,582*

Lyssacina Zittel Vm,236

Macrocheilus Phillips 11,367,384; V.593; Vm,143

acutum (Sby.) n,368

altonense Woi then V, 593* ; VTTT. 143*

elongatum Phill 11,368

(?) fustforme Hall 11,375

harpula Phill , 11,368

intercalare M. & W 11,371*

japonicum A. Ad n,369

limnaeif orme McCoy 11,384

maculatum Kon n, 368

mediale M. & W II, 370*

newberryi (Stev.) 11,368; V.594*

primigenium (Conr.) 11,368,370,372

pulchellum M. & W n,371

symmetricum King 11,369

ventricosum Hall 11,368

sp. indet 11,372*

Macrodon Lycett , V.575 ; VHI, 123

delicatus M. & W V.575*

sangamonensis Worthen VIII, 123*

tenuistriatus M. & W V.576*

Macrostylocrinus Hall n, 151

(Malleus ?) orbicularis McCoy 11,258

Mammalian remains in the Drift VLU,8

Mammoth IV,36,46; V.237; VI, 214; VIII, 8

Mantis 111,567

Marraeanthus St. John and Worthen VI, 465

rectus (N. & W.) VI.466*

Marsupiocrinus Phillips n, 170, 172

C£elatus Phil n,172

tennnesseensis Boem 11,172

Martinia McCoy n,155,298

Mascalodus VI.285

Mastodon Cuvier 1V.36,46.113,193,242; VI.214; Vm.8

Mazonia Meek and Worthen 111,563

woodiana M. & W III,563t

1 1 () GfcNEKAL INDEX.

Meekella White and St. John V.571

striato-costata (Cox) V.571*

Meekopora Ulrich VIII.347,383,482

" (?)aperta Ulr VIII, 485*

approximata Ulr VIII, 484*

clausa(Ulr.) VIII, 315t, 485*

eximiaUlr VIII.383.483*

Megalomus Hall 111,292

" (?) dixonensis M. & W 111,298

Megalonyx Jefferson IV, 40; VIII.8

Megambonia ly oni Hall II, 156

(Meganteris) olongatus (Vanuxom) IH.-lOi

( " ) ovalis Hall 111,401

Megaptera Meek and Worthen

casei M. & W 111,337*

Megathentomum pustulatum Scudder III. 570t

Megistocrinus Owen and Shumard 11,151,210; V.393; VIII, 107, 169

amplux M. & W ....V, 394,395

brevicornis Hall V.395

crassus White V,395

evansi O. & S V.393,395

( " ) infelix Winch. & Mar 11,210

knappi Lyon II, 210 .

( " ) mareouanus Winch. & Mar 11,210

nobilis Wachs. & Spr VIII.169*

parvirostris M. & W V.396*

parvus Wachs. & Spr VIII, 171*

plenus White V.395

spinulosus Lyon 11,210; V.393

superlatus Hall V.395

whiteiHall V.394,397*

(Melania) fusiformis Munster ; — 111,302

(Meleagrina) kevigata McCoy 11,333

( " ) pulchella McCoy 11,333

Melocrinus Goldfuss 11,147,209

Melonites Owen and Norwood n, 227, 247

( " ) danre M. & W II,248t,249t; III,524t

multiporus O. & N II,227t,228t,248; III,524t

(Melanopsis Meek and Worthen) 11,249

Mclosaurus Meyer II, 140

Membraniporidas VIII.3G6

Menopoma Harlan II, 139

Merista Suess Ill, 376

lajvis (Vanuxem) 111,376*

Meristella Hall 111,354

sp 111,354*

Mesodmodus St. John and Worthen VI, 290,339

explanatus St. J. & W VI,293*,295

exsculptus St. J. & W VI, 291*. 294, 297

ornatus St. J. & W VI,294*

Metoptoma Phillips 111,506

oblongaPhill 111,506

pilous Phill 111,506

Solaris (Kon.) 111,506

" (?) umbella M. & W 111,506*

undata Winch ... III. 507

GENERAL INDEX. 117

Miamia Dana in, 566

' ' bronsoni Dana ) Ill, 566

danae Scudder Ill, 5661

Michelia Rcemer 11.377

Michelinia favosa Kon 11,414

Microcyclus Meek and Worthen 111,420

discus M. & W 111,420*

Microdoma Meek and Worthen ., V.598

conica M. & W V.598*

(Microspongia Miller and Dyer) VIII, 226, 228,229

( gregaria Miller) VIII, 229

Millepora Lamarck 111,305

( " ) gracilis Phill VIII, 402

Mitoclema Ulrich VIH,337.369

ciiictosum Ulr VIII.SO'J*

(Mitra sp. Cumberland) 11,274

Modiola Lamarck VIII.125

concentrica Hall Ill, 439

illinoiensis Worthen VIII, 125*

( " )lingualis Phill 111,536

Modiolopsis Hall m,294,438

carrollensis Worthen (to be substituted for M. subnasuta) Bull. I,p.38.

gesneri Bill ! 111,2%

modioliformis M. & W 111,294*

orthonota M. & W. (See M. rectiformis) 111,295*

" (?) perovata M. & W Ill, 438*

rectiformis Worthen, to be substituted for M. orthonota, Bull. No. I,p. 38.

subnasuta M. & W. (See M. carrollensis) VI, 494*

sp. indet. (cast) VI. PL xxiii,fig.2*

Monactinellidffi Zittel VIH,220,233

Monakidae Marshall VHI.238

Monopteria Meek and Worthen II, 339

gibbosa M. & W 11,340*

longispina (Cox) 11,336,341

Monotis Bronn V.573

eregaria M. & W V.573*

( . " )hawni M. & W...' 11.338

' ' salinaria Brohn 11,337

Monotrypa Nicholson VIII.379,407,455,462

rectimuralis Ulrich VIH,308t,309t , 462*

subglobosa (Ulrich) VIII, 4i;2

undulata (Nicholson) VIII,379, 462

MonotrypeUa Ulrich .VHI,377,451

sequalis Ulr VIII,308t,309t,377.453

appressa Ulr VIII, 453*

crassimuralis Ulr VIII, 452*

pulchella (Edwards and Haime) VIII, 453

quadrata (Rominger) VIII. 452

subquadrata Ulr VUI, 452

Monticulipora d'Orbigny VIII.370,407

( " ) flliosa d'Orb VIII, 407,456

( ) frondosa d'Orb Till, 407, 414

lamellosa Ulr VIII, 408*

mammulata d'Orb VIII.370. 407

( " ) ramosa d'Orb VIII. 107

winckelli Uh- VIII, 408*

Monticuliporidae Nicholson (Ulrich emend.) VIII, 338, 369, 407

Musronella spinosissima var. major Hincks VIII, 305

118 GENERAL INDEX.

Monticava d'Orbigny VIII.340

(MontlcuUpora) petropoiitana (Pander) 111,304

Murchisonia d'Arohlac and Verneuil 11,317,373,383; 111,317; V.599; 7111,141

' bicincta Hall 111,317*

inornata M. & W V.599*

keokuk Worthen VIII.141*

lasallensis Worthen VIII, 141*

minima Swallow II, 383

( " perangulata Hall) 111,317

Myalina deKoninck 11,281,300,341; 111,358.535; V.582; VI, 524; VIII.127

" angulata M. & W 11,300*

aviouloides M. & Hayd ....v 11,345

concentrica M. & W .". 11,281*

" kansasensis Shum 11,345

" keokuk Worthen VI, 524*

" meliniformis M. & W 11,343*

monroensis Worthen VIII, 127*

perattenuata M. & Hayd : 11,342; V.582*

' ' permiana Swall . . . 11,343

recta Shum 11,342

recurvirostris M. & W 11,344*

sancti-ludovici Worthen V, 540*

squamosa (Sby) 11,342

subquadrata Shum II, 344

var. ampla M. & Hayd 11,336

" swallovi M. Ch 11,336,341*

Mylacris anthracophila Scudder — Ill, 568t

Myliobatis Cuvier 11,59; VII.199,210

aauila (L) IV.365

Myliodonts VI,299,363,472

Myriacanthus pemigranulatus Rom'sky VI, 468

Myriapoda 11,409; 111,556

Mytilus SQuamosus Sby 11,342

Myxospongia Hseckel VIII, 220

Naiadites carbonaria Dawson Ill, 535

Natica Adanson .

( " ) altonensis M. Ch V.595

( " ) mariae Murch 11,364

( " ) plicistria Phill 11,364

( " ) ventrieosaN. & P 11,366: V.592*

Naticopsis McCoy 11,363,368; V.592; VIII.144

altonensis M. Ch V.595*

" (?)var. gigantea V,P1. xxviii.flg. 12*

biserialis (Phill.) 11,364

(Trachydomia) 'brevis (Sby) II, 364

madisonensis Worthen VIII, 144*

(Trachyd.) mariae (Murch.) .- 11,364

nanaM. & W 11,365*

(Trachyd.) nodosa M. & W 11,366*

" var. hollidayi M. & W 11,367*

". phillipsi McCoy '. 11,364

" * plicistria (Phill.) 11,364

( " ? pricei Shum.) V.592

subcostata Goldf 11,364

subovata Worthen V, 595*

ventricosa (N. & P.) 11,364; V.592*

GENERAL INDEX. 119

Naticopsis (Trachyd.) wheeled (SwalL) n,364; V.595*

Nautilus Breynius (L.) : H, 161, 305.386; ¥,522.543,608; YI.531; VIII,148

biangulatus McCoy n, 162

( " bistrialis Phill.) 11,305

capax M. & VT VI.532*

cariuiferous Sby n,162; Y.522

chesterensis M. & W 11,306*

coUectus M. & W V,544*

coxanus M. & W Y.543*

digonus M. & W 11,163*

disciformis M. & W Y.522*; YI.531

discus Sby V.523

dorsalis Phill YI.532

edwardsianus Kon II , 162

' " globatus? Sby : 11,162,305*

highlandensis Worthen YI,531*

lasallensis M. & W Y.610*

latus M. & W Y.608*

leidyi M. & W Y.524*

montgomeryensis Worthen r . . .: YIII, 148*

niotensis M. & W Y, 523*

( " nodocarinatus M. Ch.) 11.387

occidentals Swall n,386

omalianus Kon n, 162

ornatus? var. amplus M. & W VI, PL iwii.flg. 1 and 2*

( " (Endolobus) peramplus M. & W.) 11,308

pinguis Kon n, 162

planorbiformis M. & W 11,386*

planovolvis (?) Shum V.P1. xxx.flg. 3*

( " quadrangulus M. Ch.) 11,387

( " ) rockf ordensis M. & W 111,459*

sangamonensis M. & W H.386*

(EndoL) spectabilis M. & W 11,308*

stygialis Kon. H.162

{ " subglobosas M. & W.) m,305

sulcatus Sby 11,162

(Trematodiscus) trisulcatus ''. & W 11,162*

tuberculatus Sby 11.306,308

winslovi M. & W Y.609*

( " wrightiFlem.) n,305

sp. indet Y.P1. itr.flg. 2*

Nemacanthus Agassiz YI, 440

Nemataxis Hall YIII, 402

(Nematoerinus) wachsmuthi M. & W 111,465*

Neinatopora Ulrich YHI, 363. 401. 406, 644

alternata Ulr YIII, 646*

concava Bill.) Yni,645

delicatula Ulr YIII.646*

fonnosa (Bill.) Y]JI,645

fragilis Ulr Yin, 646*

lineata (Bill) YIU,646*

minuta (Hall) YIII.645

quadrata Uh- YIH, 401, 644*

retrorsa Ulr YIII, 645*

striatopora (Bill.) VIII,645

strigosa (BUI.) Yin,645

120 GENERAL, INDEX.

Nerita haliotis Sby 111,385

( " price! Shum.) V.592

" spirata Sby 11,366

( ' • ) subcostata Goldf II, 364

Nicholsonella Ulrich VIII.374,421

cumulata Ulr VIII.374,423*

ponderosa Ulr VIII.374,422*

vaupoliUh- VI II, 421, 422, 423

Nipterocrinus Wachsmuth V, 434

arboreus Worthen ...V.436*

wachsmuthi M. £ W V.435*

Nucleocrinus Conrad 11,275 ; VII, 357

" angularis Lyon VII, 360

" ? canadensis Montgomery VII, 357

e;ogans Conr VII.362

lucina Hall VII.360

meloniformis Barris VII, 361

Nucula Lamarck V.589; VIII.128

" ? beyrichi Schaur V.589*

illinoiensis Worthen VIII, 128*

" parva McCoy V.589*

Nuculana Link 11,283

" ? curtaM. &W 11,283*

sp. indet V.P1. xxvi.fig. 10*

Obolus Eichwald 111,351

(Trimerella?) conradi Hall Ill, 351*

davidsoni Salter Ill, 351

Odontaspis Agassiz VI.276

Odontocephalus Conrad Ill, 416

tegeria (Hall?) 111,417*

arenarius M. & W 111,417

' ' selenurus Conr Ill, 417

sp. indet 111,416*

Odontochile Ha wle and Corda 111,367.391

(Odontotrypa Hall) VIIL383

Oligoporus Meek and Worthen 11,226,247

danze M. & W II,248t,249*; III,524t; V.477

nobilis M. & W V.476*

(Olivanitos Troost) VII, 357

Ollacrinus Cumberland II, 225

( " ?)flscellus M. & W 11,225

Omphalotrochus Meek 11,159

Onchus hainatus Ag VI.450

Oncoceras Hall Ill, 446

Onychaster Meek and Worthen 111,526; V, 474

barrisi (Hall) V.476*

flexilis M. & W 111,5261; V,475,510*

Onychocrinus Lyon and Casseday ....11,242; 111,492; V.498,552; VI.520; VII.307; VIII.199

asteriformis (Hall) 11,243; 111,494

distensus Worthen VII, 307*

diversus M. & W 11,243; III,492t*

exsculptus Ly. & Cass 11,247; V.498*

magnus Worthen VI, 520*

meeki (Hall) V.553

GENERAL INDEX. 121

Onychocrinus monroensts M. & W II, 244*

. norwoodi M. & W II, 245*,247t

whitfleldi (Hall) V, 552*

Ophileta Yanuxem 111,313

' ' compacta Salter 111,314

owenana M. & W HI, 313*

Ophioraphidites Carter Vm,245

Ophiuroidea V.509 ; VH.330

Oracanthus Agassiz 11,117,126: VI,472,477; VII.255

abbreviatus Newb 11,118; VI, 480

( " consimilis St. J. &W.) VI.478*; Vn,255

milleri Ag VI, 479

?obliauus St. J. & W VI.477*; VH.257

( " )pnigeus X. & W 11,117*; VI.480

pustulosus Ag VI, 4C8

rectus St. J. & W VH.257*

vetustus Leidy VI.479; VH.255*

Ormoceras Stokes 111,298

backi Stokes in, 298*

tenuifllum Hall HI, 298

Orodus Agassiz 11,62,73: IV,358,360; VT,285,291, 295, 315,335,337; VH.65

alleni St. J. & W VI,310*,318

carinams St. J. & W VI.300, 307*,309

cinctus Ag H, 64, 65

( " ) corrugatus N. & W IV,358*; VI.311,316

" daedaleus St. J. & \V VI.301*

decussatus St. J & W VI.300*

elegantulus N. & W II, 64*. 67; VI.302,309

fastigiatus St. J. & W VI.306*

gibbosus (N. & W.) VI.308

major St. J. & W VI.300,302*

mamillaris N. & W 11,66*; VT,301

( " )minusculus N. & W II,67*,69; VI.339

minutus N. & W H,68*; VI.308

multicarinatus N. & W 11,62*

neglectus St. J. & W VI.308*

ornatus N. & W I,,65*,68; VI.308

parallelus St. J. & W VI.295*

parvulus St. J. & "W VI, 309*

" plicatus N. & W - 11,63*; VI.301,309

ramosus Ag 11,63; VI, 303

tuberculatus N. & W 11,66*; VI.307

turgidus St. J. & W VI.310*

varicostatus St. J. & W VI, 304*, 308, 311

whitei St. J. & W VI.297*

Orophocrinus von Seebach VII,347; VIII,201

conieus W. & Sp VIII,201*,204

fusiformis "\V. & Sp VIII,201,203*

graciUs (M. & W.) V.467*

stelliformis (O. & S.) V.464*; VII.347,349; VIII, 201

Orthis Dalman 11,322; IH, 372, 410, 423; V.571; VIII, 106

carbonaria Swallow V.571*

elegantula Dalman 111,374

" hybrida Sby? 111,371*

iovensis Hall Ill, 424

var. furnarius Hall in, 424*

( " lasallensis M. Ch.) V.570

—16

122 GENERAL INDEX.

Orthis mac-farlanei Meek HI, 423*

musculosa Hall 111,410

oblata Hall 111,371

' ' perelegans Hall Ill, 374

' ' planoconvexa Hall Ill, 374

' ' resupinata Martin VIII, 106

resupinoides Cox VIII, 106*

( " richmondi M. Ch.) V.570

( " rugosa Buch.) 111,426

striatula d'Orb Ill, 425

subcarinata Hall Ill, 373*

testudinaria Dalman Ill, 373

sp. indet Ill, 410*

(Orthisina crassa M. & Hayd.) V, i>70

Orthoceras Breynius 11,286,304; 111,298,318; V.612; VI, 503, 512; VII, 323; VIII, 148

anellus Conr 111,318*

angulatum Wahl VI, 504*

( ' ' annulato-costatum M. & W.) see 0. randolphense. . . , II, 304*

(Ormoceras) backi Stokes? 111,298*

crebescens Hall VI, 504

crebristriatum M. & W VI, 503*

dilatatum Kon 11,287

expansum M. & W 11,286*

jolietense M. & W VI, 505*

illinoiense Worthen Vn,323; VIII.148*

laphami M. Ch VI, 504

lasallense Worthen Vn,324; VIII.149*

maro Bill 111,320

medullare Hall? • VI.504*

munsterianum? V.P1. xxiii.flg. 5*

' ' occidentale Winch VI, 513

okavense Worthen VII.324; VIII, 149*

pauciseptum Hall VI, 505

" randolphense Worthen; this name should replace O. annulato-costatum
M. & W., the latter name being pre-occupied. (Bulletin No. 1, page 38.)

rectum Worthen VI, 504*

rushense M. Ch V.612*: VIII.149

striilineatum M. Ch VI.504*

tenuifllum Hall Ill, 298

unionense Worthen VI, 505*

winchelli M. & W VI.512

sp. indet V, PI. xxx, fig. 5*

" VI1I.151

Orthonema Meek and Worthen 11,380; V.590; VIII.145

' ' carbonarium Worthen VIII, 145*

conicum M. & W V.590*

salteri M. & W 11,381*

Orthonychia Hall 111,385,387

( " ) pyramidata Hall 111,389

( " )subplicata (M. & W.) 111,385,457*

( " )subrecta Hall 111,385,387

Orthopleurodus St. John and Worthen VII,61,85,190

carbonarius (N. & W.) VII,177,192*

convexus St. J. & W VII, 193*

novimexicanus St. J. & W VII, 195*

(Orthopora Hall) VHI, 402, 647, 662

GENERAL INDEX. 123

Osteophorus Meyer II. HO

Oxyrhina crassa Ag VHI,4t

Pachastrella Schmidt THI, 245

Pachydictya Ulrich THI, 390, "-22

acuta (Hall) Tin,522,526

bifurcata (VanCleve) Yin, 526

everetti Ulr VIII. 523*

fenestelliformis (Nich.) VIII, 526

var. eorticula Ulr YTII. 526*

flrma Ulr Till, 525*

gigantea Ulr YHI, 524*

occidentalis Ulr YII I

obesa Foerste YHI,522

robusta Ulr Yni,390,522

splendens Ulr VHI.523*

(targida Foerste) • YHI, 526

(Palfearca Hall) 111,309

Palasasteridae .' 11,278; YII.327

(Palaeasterina) flmbriata M. & W H, 278

Palseechinida? McCoy 11,229.247,294; 111,523: Y.473

PalEeechinus McCoy II. 22*. 229 ; IU.523; Y, 473

burlingtonensis M. & TV II,230*,231t; V.474

danae M. & W 11.251

graeifis M. & W Y.473*

Palfeeschara Hall Yin.354,366

Palaeescharidae Ulrieh YIII, 366

Paljeocampa Meek and Worthen H.410: in, 565

anthrax M. & TV 11.410*

Palaeocaris Meek and Worthen 11.403: HI. 552

typus M. & \V n,403*,405*; in,552^

Palaeocrinoidea Wachsmuth and Springer. ...H, 147, 167, 234, 263, 288, 310; in,421,463,5U;

Y. 323-339, 483,530,546,561; VH, 269, 335. 341; YHI, 83,157.168

Palseomanon Roemer YHI, 212.214. 217,223,234

bursa HaU Y1H,234

cratera Roemer YIII. 234

Palaeoniscus de Blainville n.17: IY.347

gracilis N. \- W F\'.347*

peltigerus (Newb.) n,!?^; IY.348

Palaeopterina Scudder 111,566

(Panopasa?) lunulata Gein 11,347

(Paradoxides) boltoni Bigsby VI.508

Pasceolus Billings IH.345

( " ?) dactylioides (Ow.) 111,345*

(Patella) Solaris Kon. 111,506

Pattersonia S. A. Miller YELL 212. 217. 240

difflcilis Mill YIH.240

Pecten Muller.

( " ) aviculatus Swall in,455; Y.588*

( " ) clevelandicus (SwalL) 11,331

consimilis McCoy 11,333

dissimilis McCoy 11.333

maximus L 11,333

( " ) neglectus Gein Y.,589

( " ) occidentalis Shorn H.331

124 GENERAL INDEX.

Pecten pusillus Munster. 11,334,336

sericeus (Vern.) 11,335,336

sowerbyi McCoy 111,455

( " ) tenuilineatus M. & W 11,334

Pelmatozoa VIII, 163, 201

Peltodus Newberry and Worthen IV.862; YI,409,414

curtus N. & W IV.355*

plicomphalus St. J, & W VI.411*

pulvinulus N. & W IV.362

quadratus St. J. & W VI,410*,413

transversus St. J. & W VI.412*

unguiformis N. & W IV, 363*; VI.409,413

Penniretepora d'Orbigny VIII.398,615

Pentacrinus Schlotheim VIII, 161

Pentagonia Cozzens Ill, 380

Pentamerus Sowerby 111,428

comis (Owen)? 111,428*

( " ) eloneatus Vanuxem Ill, 402

( " galeatiformis M. & W.) 11,325; IH.4'28

galeatus Dalman 11,325; 111,429

occidental Hall 11,325; 111,428

subglobosus M. & W 111,429*

Pentremites Say 11,171,274; 111,496; V.461,506; VI, 521; VII.346

' ' abbreviatus Hambach VII.351

burlingtonensis M. & W V.461*

clavatus Shultze V.364

cornutus M. & W 11,276

elongatus Shum Ill, 499

godoni Defr V, 461

inflatus Gilb V.466

lineatus Shum VI, 521

( " )melo (O. & S.) 111,496

( " " var.) projectus M. & W 111,496

( " )norwoodi O. & S 111,496; V.473

(Tricoelocrinus) obliauatus Koeraer VI, 521*

( " )reinwardti Shum VII.357

roemeri Shum V,509

( " ) stelliformis O. & S V.464; VII.347; VIII.201

{ " subtruncatus Hall) VII,357

' ' (Tricoal.) varsoviensis Worthen VI, 521*

. " (Troostocr.?) woodman! M. & W V.506*

wortheni HaU? V.506*

Pentremitidea d'Orbigny, VII, 363

' ' americana Barris VII, 363

clavata iSchultze) ....VII,364

Periplectrodus St. John and Worthen VI, 324

compressus St. J. & W VI, 326*

expansus St. J. & W VI,327*

warreni St. J. & W VI,325*,327

Perischodomus McCoy 11,229,294; VII.333

illinoiensis Worthen and Miller VII, 333*

Perischoechinidse 11,225,247,294; 111,522; V.473,510; VII.331

Pernopecten WincheU 11,334; III, 453

cooperensis (Shum.) 11,334

limiformis White and Whitf 111,455

' ' shumardanus Winch.? Ill, 453*

Peronella Zittel VIII.218,280

GENERAL INDEX. 125

Peronopora Nicholson VIII, 370, 412

decipiens (Borainger) Vni,370

Petalodontidae Newberry and Worthen 11.31

Petalodus Owen 11,31,35,47,73; IV.355; 71,367,377,394,397,403,413

acuminatus Ag 11,32,37; VI, 396

alleghaniensis Leidy 11,32; VI, 396

( " )bellulus St. J. & W VI,397,398*

curtus? N. & W VI.394*

destm.-tor N. & W II,32,35*,46; VI,3%

bastings! Ow 11,32; VI.396

hybridus 8t J. & W VI, 394*

hevissimus Ag VI, 399

linguifer X. & W 11,32,37*; VI.394,400

proximus St. J. & W VI.395*

Petalorhynchus Agassiz n, 32,40; VI, 405, 414

distortus St J. & W "VI, 406*

pseudosagittatus St J. & W : VI, 405*

psittacinus Ag 11,32; VI, 408

sagittatus Ag n,32,40; VI. 406, 408

spatulatus St. J. & V? VI, 408*

striatus N. & W 11,32,40*; VI, 406

Petalotrypa Ulrich VIIE, 377,453

compressa Ubr VIII, 377, 454*

delicata Ulr Vm,454*

Petigopora Ulr VIII, 372

gregaria Ulr VHI.372

Petrodus McCoy 11,70; IV,369; VI.314

acutus N. & W II, 72*

occidentalis N. & W. 11,70*; IV.370; VI, 461

patelliformis McCoy 11,71

" (?) pustulosus N. & W IV, 369*

Petrospongiae II, 145,233,262

Phacelopora Ulrich VIII, 368,406

constricta Ulrich Vni, 406*

pertenuis Ubrich VIH.368, 406*

Phaceloporidae Ulrich Vni,368

Phacops Emmerich 111,447

rana (Green) Ill, 447*

Phaenopora Hall Vm, 349, 392. 520

constellata Hall VIH,392t

expansa HaU and Whitfleld Vin,391,392t-

explanata Hall VED,392

( " fenestelliformis (Nich. sp.) Ulrich) Vin,526*

lindstroml Ukich VIII, 392t

( " ) multipora Hall VHI,520

Phaenoschisma Etheridge and Carpenter VII,353,356

verneuili Eth. & Carp VII, 356

Pharetrones Zittel VIII.239

Phi.lipsia Portlock : V.525.612

bufo M. & W V.528*

( " ?) eUiptica M. & W 111,462

portlocki M. & W V.525*

sangamonensis M. & W V.615*

scitula M. & W V.612*

Philocrinus de Koninck 11.315; V.446

" (?)antiauus M. & W V.449

( " Jconoideus M. & W II,318t

126 GENERAL INDEX.

Philocrinus nebrascensis M. & W V.446

( " pelvis M. & W.) II,317t*

( " ?) tuberculatus M. & W 11,319

typus M. & W V, 446

" (?) white! M. & W V,449

Phcebodus St. John and Worthen VI, 251

sophiae St. J. & W VI, 251*

Pholidocidaris Meek and, Worthen V, 510

irregularis M. & W V.512*

Phragmoceras Broderip VI,506,511

' ' byronense Worthen VI, 506*

nestor Hall VI.506

walsbiM. & W VI.511*

Phragmodictya Hall VIII,237

catilliformis Whitfleld VIII, 237

lineata Hall VIII, 237

patelliformis Hall VIII, 237

Phrynidae 111,568

Phyllodictya Ulrich VIII, 348, 390,528

frondosa Ulr VIII.390

Phyllopoda 111,540

Phyllopora King VIII.358, 397,612

aspera Ulrich VIII, 613*

( " )corticosa Ulr VIII, 639

ehrenbergi King VIII, 358, 397, 612, 613

superba Ulrich VIII, 613*

variolataUlr VIII.639

( " )sp. indet VIII.612,P1. Iv.flg. 10*

Phylloporina Ulrich VIII,399,639

corticosa (Ulr.) VIII, C30

dawsoni Ulr VIII, 331*, 358, 639*

granistriata Ulr VIII, 639*

reticulata Hall VIII, C39

" trentonensis Nicholson VIII, 639

variolata (Ulrich) VIILG'W

PhylloporinidEB Ulr VIII.362,399

Physetocrinus Meek and Worthen V,349,351,363

asper M. & W V.351*

cancellatus (Hall) V, 349

dilatatus M. & W V,363*

ornatus (Hall) - V.363

reticulatus (Hall) V.363

subventricosus M. Ch... V.349,364

ventricosus (HaU) V, 349

Physonemus Agassiz IV.373; VI, 448; VII.252

altonensis St. J. & W VI, 454*; VII.252

arcuatus McCoy IV.373; VI.448

carinatus St. J. & W VI.452*

cestriensis St. J. & W VI.455*; VII.252

depressus St. J. & W VI, 452*

falcatus St. J. & W VII, 252*

gigas N. & W IV.373*; VI, 448, 453, PI. xviii.flg. 6-10*

parvulus St. J. & W VI, 453*

proclivus St. J. & W VI, 451*

subteres (Ag.) VI, 448

GENERAL, INDEX. 127

Physospongia Hall VIII.237

alternata HaU Vin,237

colletti Hall VTH, 237

dawsoni (Whitfleld) Vin,237

Pileopsis Lamarck 111,384

( ' ' tubifera) 111,385

( " JvetustaSby 111,3*5

(Pileotrypa Hall) YIII,382.383

Pinacodus Agassiz VH, 200, 232

gonoplax Ag VII. 232

Pinacotrypa Ulrich Till. 384

elegans (Eominger) Yin, 385

Pinna Linnaeus VI.524; Vm.lll

missouriensis Swall Vni.lll

sancti-ludovici Worthen Yni.lll*

spatula McCoy YI.524

subspatulata Worthen YI, 524*

Pinnatopora Yine YIII.358, 397,566,614

bellula Ulr Vni.362*,619*

conferta Ulr Yin, 615*. 618*

elegans Young and Young Yin,615*

flexicarinata (Y. & Y.) VIH, 620

flexuosa Ulr Yin, 617*

laxa Young and Young YUI.615*

retroflexa Y. & Y Yni,615*

sedrsvieki Shrubsole Ym,627

( " ) simplex Yine Yin,361,636

stellipora Y. & Y YIII,315t

striata Ulr Yin,617*

tenuiramosa Ulr VIII, 619*

trilineata (Meek) Yin, 615', 620*

vinei Ulr VIII, 616*

whitei Fuerste Yni,620

youngi Ulr VIII, 615*

Pisces II. 11-134 ; IV, 313-374 ; YI,245^88 ; Vn,55-264

" Synoptic tables of II. i-v. 128-134; VI.483-488; Vn,261-264

Placunopsis Morris and Lycett , V.578

carbonaria M. & W V, 578*

jurensis Roemer V.579

Plagiostomi VI.276

Plaryceras Conrad n,227; HI, 384,387,406, 441,457; V, 334-339,516,594

aequilaterale Hall Y, 518*

biseriale Hall • HI.509*

flssurella Hall 111,385,457 ; V, 519*

gebhardi Conr UI,S88,406

haliotoides M. & W in, 458*

infundibulum M. & W Y,334,517*

' ' intermedium Hall in.387

multisinuatum Hall ni,387

pabulocrinus R. Ow V, 335

(Orthonychia) pyramidatum Hall? HI.389*

( ) auincyense M. Ch ni,510*

(Exogyroceras) reversum Hall in, 508t*

?I linigerum Worthen Y, 594*

spirale Hall III.389*,406*

(Orthon.?) subplicatum M. & W 111,385,457*

128 GENERAL INDEX.

Platyceras subrectum Hall V.335,387

" subsinuosum Worthen, substituted for subundatum. Bull. No. 1. p. 38.

( " subundatum M. & W.)— See P. subsinuosum « 111,387*

tortuosum Hall 111,406

tubiferum (Sby.) III. 387

( " )umbellaM. & W 111,506

uncum M. & W V, 516*

" ventricosum Conr 111,388,405.441*

Platycrinus Miller 11,170,172,242,264; 111,466,511; V, 450, 506, 555; VII,306; YIII,186

jsqualis Hall V,456*

" americanus O. & S V.451

(Pleurocrinus) asper M. & W 11,172;' 111,468+*

burlingtonensis 0. & S V.452M60; VIII, 186

(Marsupiocrinitesj caslatus Phill *. 11,172

discoideus Hall 11,175

freorgii Hall 4 11,265

(Centrocrinus) gigas Gilb 11,172

granulatus Mill 11,172: 111,513

halli Shum V.454*; VIII.189

hemisphaericus M. & W..... 111,511+*; V,334,506*

incomptus White V, 453, 455, 459*

( " inornatus M. Ch V.452

laevis Miller II, 171

monroensis Worthen VII, 306*

(Pleuroc.) mucronatus Austin 11,172

mullerianus Kon T II, 172

niotensis M& W III,513t*

nodibrachiatus Hall 11,172; 111,491

( " olla Hall) V.454,460

olla Kon V.460

parvulus M. & W 11,171; V.555*

penicillus M. & W 11,266*

perasper M. & W 11,172

pileiformis Hall VIII.186

planus 0. & S.? 111,467*; V,452*,456; VIII,188*

plenus M. & W 11,267*

plumosus Hall II, 173

polydactylus Troost II, 267

prattenanus M. & W 11,264*

pratteni Worthen VIII, 189

sarae Hall Ill, 514

scobina M. & W Ill, 466t*

( ' ' spinosus Austin). .-. II, 172

(Pleurocr.) subspinosus Hall 11,172,173*; V.452*

symmetricus W. & Sp VIII, 186*

(Marsupiocr.) tennesseensis Koem 11,172

tenuibrachiatus M. &W V,450*

( " triaconta-dactylus Austin) ..11,172

truncatulus Hall VIII, 188

' ' (Pleurocr.) tuberculatus Miller 11,172

( " ) tuberosus Hall 11,172

wortheni Hall Ill, 467 ; V, 451

( " sp.) : 11.167,168

(Platynotus) boltoni Bigsby VI.508

Platysomus Agassiz I V.317

circularis N. & W IV, 347*

orbicularis N. & W IV, PL iii.flg. 1*

GENERAL INDEX. 129

(Platystoma) tumidum M. 4f W 11,360

Plectostylus Conrad 11.367

Plectrodus Agassiz YI.324

Pletirocrinus Austin II, 170, 172, 173,290; 111,468

asper M. & W 11,172; HI,468t*

mucronatus Aust H. 172

subspinosus Hall II, 172

tuberculatus Moll H, 172

tuberosus Hall n.172

Pleurodeles Mich 11,137

Pleurodictyum Goldf uss in, 407

problematicum Goldf? HI, 407*

Pleurogomphus Agassiz VII.200

Pleurophorus King n,347; m,535; V.589; YI.529; YIII.123

(?)angulatus M. i W YI.529*

chesterensis Worthen YIU, 123*

costatiformis M. & W HI.535t*

costatus (Brown) 11,348; HI.536

minimus Worthen Vin,124*

monroensis Worthen Yin, 125*

oblongus Meek Y.589*

subcos-tatus M. & W - 11,347*

subcuneatus M. & Hayd n,348

Pleurotomaria Defrance 11,260,303,351,373,380; m,359; V.600; Yn,324; Yni,135

adamsi Worthen Vm,137*

( " angulata Conr.) HI.314

beckwithana M. Ch V, 601

bicarinata Sby n,359

brazoensis Shum? II, 354*

casii M. & W 111,359*

chesterensis M. & W 11,303*

conica Phill H, 260

coniformis Worthen (substituted for P. conoides.) Bull 1,38

( conoides M. & W.) Y.603*

coxanaM. i W Y.600*

( coxana Worthen) YIH.138

cyclonemoides M. & W m,360

giffordi Worthen Yin,135*

granulo-striata M. &, W-. H, 356*

gurleyi Meek V.PL xxx.flg. 6*

illinoiensis Worthen YHI.ISS*

intertexta M. & W 11,355

iovensis Worthen YIII.138*

( ) lentioularis (Sby.) 111,316*

micronema M. i W Y.603

missouriensis (Swall.) 11,360; Y.604

montezuma Worthen YII, 324 ; YIII, 136*

nauvooen-is Worthen YIII, 137*

obtusispira Shum _ Y.604

pauper Hall in,361

pratteni M. & W 11,357*

proutana Shum 11,352

riddelli Shum H.360

scitulaM. & W H.353*

shumardiM. & W U,260*

gpeciosaM. i W 11,352.*

—17

130 GENERAL INDEX.

Pleurotomaria spironema M. & W V, 601*

subconstricta M. & W V.351*; VIII.136

subscalaris M. &W 11,360*

subsinuataM. & W 11,358*

tabulata Conr II, Ml

tenuicincta M. & W 11,355*

(?)tumidaM. & W 11,361*

tuberculosa Defr Ill, 317

turbiniformis M. &W 11,359*

Jumbilicata Hall 111,314*

valvatiformis? M. & W V.602*

yvani Leveille 11,369

sp. indet V.P1. xix.fig. 1*

(Plicatula) strlato-costata Cox V, 571

PnigeacanthusJSt. John aud Worthen VI, 480; VII.259

( " deltoides St. J. & W.) : VI, 475, 479, 480*

pnigeus N. & W 11,117*; VI.480*

trigonalis St. J. & W VII.259*

Poecilodus Agassiz 11,96; IV.363,366; VII, 61, 131

( " aliformis McCoy) ...VII.144

angustus Ag 11,96; IV. 366

carbonarius St. J. & W VII.139*

cestriensis St. J. & W VII.131,135*

convolutus M. & W IV.366*

jone^i Ag 11,95; VII. 136

marginatus 11,96

obliquus McCoy (Ag.?).. 11.95; VII, 136

( " ornatus N. & W.) 11,95*; IV.366; VII.112

( " parallelus McCoy) VII.144

( " )rugosus N. & W 11,94*; IV,3(i6; VII,112.119,120

sancti-ludovici St. J. & W VII.131*

springer! St. J. & W VII.139*

( " )subkevis McCoy 11,99; VII.141

varsoviensis St. J & W VII, 131*

wortheni St. John VII, 136*

PollakidsB Marshall VIII.238

Polyphemopsis Portlock 11,372.384; 111,361; V,5%; VIII.144

brevis M. & W Ill, 362

bulimiformis (Hall) 11,373

canaliculata ( Hall) II , 373

chrysalis M. & W V.596*

elongata Portl 11,373; 111,361

fusiformis (Sby.) 11,373; 111,361

inornata M. & W 11,374*

(?) keokuk Worthen VIII, 144*

nitidula M. & W 11,374*

peracuta M. & W _. 11,375*

(Polyphemus) fusiformis Sby 11,373

Polypora McCoy 11,421; 111,504; VIII,245,351,357, 396,585

approximata Ulr VIII, 599*

artaHall VIII. 358

' ' biarmica Keyserling VIII, 599

( " " Prout) VIII.599*

" biserialis (in error for P. biseriata) VIII, 358

biseriata Ulr VIII,315t,538>592*

burlingtonensis Ulr VIII. 587+

GENERAL INDEX. 131

Polypora celsipora (Hall) VIII, 358

cestriensis Ulr VIII, 357, 594*

complanata Ulr VIII, 597*

corticosa Ulr VIII, 596*

crassa Ulr VIII.603*

cultellata (Hall) VIII, 586*

dendroides McCoy VIII,397,585,607

distincta Ulr VIII.357,603*

eximia (in error for P. whitei) Vni,600

glgantea Waagen and Pichl VIII.603

gracilis Prout 11,422*; VIII, 357, 590*. 603

grandis Toula VIII, 603

halliana Prout 11,421; VIII,357*,587*

( " " Nich.) VIII.587

hamiltoneusis Prout 11,423*

incepta? Hall Vin,358,(Pl. Iv, fig. 1*)

koninckiana Waagen and Pichl VIII, 604

laxa (Phill) 11,423

mac-coyana Ulr VHI, 357, 588*

marginata McCoy VIII, 602

( " " Geinitz) Vin,602*

mexicana Prout 11,422

nodocarinata Ulr Vin,601*

radialis Ulr VIII,358,591*

retrorsa Ulr VIII, 591*

shumardi Prout VIII, 397, 586*

simulatrix Ulr VIII.589*

spininodata Ulr VIII, 594*

spinulifera Ulr VIII,357,598*

submarginata Meek VIII, 602*

tnberculata Prout VIII,357, 595*

( ' ' tuberculata Nich.) VIII.595

varsoviensis Prout VIII, 593*

whitei Ulr VHI,358,600*

" var. insculpta Ulr VIII.600*

(Polyporidae Vine) VIII, 358

(Polyporinae Waagen and Pichl) VIII, 359

Polyrhizodus McCoy 11,32,34,39,47; IV.357; VI, 379, 384, 391

amplus St. J. & W VI,385,387*

carbonarius St. J. & W VI, 389*

dentatus N. & W 11,34,50*; VI.388

inflexus N. & W 11,48*; IV.357

littoni N. & W IV.357*; VI.385,388, PL XIILfig. 14*

magnus McCoy 11,34,49,51; IV.358

nanus St. J. & W VI.386*

piasensis St. J. & W VI.386*

ponticulus N. & W 11,34,50,51*

porosus N. &W n,34,49*; IV,357*; VI.385

( " )pusillus McCoy 11,34,51

" radicans McCoy VI, 388, 389

truncatus N. & W IV.357*

williamsi St. J. & W VI,384",386

Polyzoa-«See Bryozoa.

Porcellia LeveiUe 111,458; VIII.138

nodosa Hall HI, 458*

peoriensis Worthen VIII, 138*

puzosi Lev III. 458

132 GENERAL INDEX.

Porocrinus Billings IJI> 329

conicus Bill • 111,331

crassus M. & W III,330t*

' ' pentagomis M. & W HI> 332*

Portlockia McCoy in, 449

rana (Green) 111,449

Posidonomya (?) rhomboidea Hall. 111,355

Poteriocrinidse VIII, 193

Poterioerinus Miller : 11,176,179,185,237; 111,484,515;

V, 405, 410, 490, 533, 561; VI, 516, 526; VII.269; VIII,86,193.

seaualis (Hall) VII.282

" arachniformis Worthen VII, 281*

asper Worthen VII, 278*

asperatus Worthen VII, 280*

bayensis M. & W < V.550*

bisselli Worthen V.546*

briareus Worthen VII,279*

buffaloensis Worthen VIII, 89*

burketi Worthen VII.270*

bursiformis White V,433

calyculatus HaU 111,485

capillaris (PhilL) 11,182

carinatus M. & W III,486t*

claytonensis Worthen VII, 288*

clytis Worthen VII,294*,301

columbiensis Worthen VII,293*,295

concinnus M. & W V.490; VII.284

coreyi Worthen VI, 516*,519

coxanus Worthen •:• VII, 269*

cultidactylus Hall VII.301*

dilatatus HaU (?) V, PI. iv, fig. 7*

( " Jegertoni Phill 11,270

elsahensis Worthen VIII, 88*

( " J.enorinis M. & W 111,481*

f ountainensis Worthen VII, 286*

goniodactylus Phill II, 182

' ' hamiltonensis Worthen VII, 273*

' ' hardinensis Worthen V, 533*

( " ) hemisphsericus Shum •. V.561

hoveyi Worthen VI.516*

illinoiensis Worthen VII,2<J9*

. " indianensis M. & W '...III,515t*; VI.517

internodius (HaU) VII.286,294

iowensis Worthen VII, 272

kaskaskiensis Worthen VII, 300*

lasaUensis Worthen VI, 526*

latidactylus Worthen VII, 275,

( " longidactylus Shum.) 11,181

macoupinensis Worthen V, 561*

mammif ormis Worthen VIII, 91*

minutus Koemer II, 182

missourienses Shum 11,181,184; VI, PI. xxxi.fig. 7*

nauvooensis Worthen VII, 282*

nodobasalis Worthen VIII.89*

obuncus White V,412

GENERAL INDEX. 133

Poteriocrinus occidentals Worthen VII, 27 8*

okawensis Worthen VII. 297*

orestes Worthen VII, 273*

? ornatissimus (Hall) 11,182

otterensis Worthen VII, 283*

peculiaris Worthen .- VEI, 298*

pencillif ormis Worthen TTI, 273 ,276*

? perplexus M. & W V, 405*

( " ) pisiformis Eoem 11,177

popensis Worthen VII. 296*

proboscidalis Worthen VI, 518*

propinquus Worthen VII, 299*

randolphensis Worthen V.551*; VIL297

richfleldensis Worthen VII. 285*

rowleyi Worthen VIII, 90*

salteri Worthen VH, 291*

(?)scoparius (Hall) 11,182

sculptus Worthen VII . 292*

similis Worthen VII, 295*

spinibrachiatus Worthen VII, k90*

spinuliferus Worthen V1II,86*,90

sublmpressus M. & W ni,485f*: V.416

subramulosus Worthen VII, 284*

(Scaphiocrinus) subtumidus M. & W 11,178

swallovi M. & W II,183*,184t

talboti Worthen -. .VII, 287*

tentaculatus Worthen VEI, 277*

tenuibrachiatus M. & W VII, 484t*

(Scaph.) tenuidactylus M. & W HI, 460t*

tenuidaetylus Worthen VII, 2?1*

ulrichi Worthen VICE, 8?*

unicus (Hall) Vn,273,278

validus Worthen VH.287*

van-hornei Worthen VI, 517*

varsoviensis Worthen VII, 290*

venustus SVorthen VII, 297*, 299. 301

(Scaph.) wachsmuthi M. & W III,488t*

(Pradocrinus) amplus M. & W Ill, 470

Prasopora Nicholson and Etheridge, Jr VIII, 371

affinis Foord -. Vin,318t

grays? Nich. & Ether VHI.371

lycoperdon (Vanuxem) Vni,318t

Prestwichia Woodward HI, 548

)danae M. & W III,547t

rotundata Meek ni,547t

(Prisconia) perelegans M. & W V.581*

Prismopora Hall VIII, 386,505,606,508

minima Ulrich VIII, 506*

trif olia (Eominger) VIII, 505*

triquetra Hall VUI.386

Pristicladodus McCoy 11,70; VI. 253

armatus McCoy VI, 257

( ) dentatus McCoy H.70; VI. 253

goughi McCoy VI. 254

springeri St. J. & W VI. 255*

Pristis Lamarck * IV.351

134 GENERAL INDEX.

Pristodus Agassiz VI, 402

acuminatus St. J. & W VI, 402*

falcatus Ag "VI, 402

Proboscina Audouin VIII»,368

Productus Sowerby 11,280,297,320; 111,412,460,528; V.569

' ' americanus S wall HI. 530

( " analogus Phill.) 111,426

( " asper McCh.) V.569

costatus Sby V.570

( " depressus Sby.) .111,426

( " elegans N. & P.) 11,297

( " " Steininger) 111,426

ellipticus M. & W ...111,460*

exanthematus Hall?? 111,412*

flemingi Sby 11,298

" giganteus (Martin) 111,529

lasallensis Worthen V, 569*

longispinus Sby 11,298,321; V.569*

magnus M. & W 111,528*

( " ) modestus Say 111,978

muricatus N. & P n,321

nanus M. &W 11,320*

nebrascensis Ow V,569*

parvus M. &W 11,297*

punctatus Mart V, 569*

( " Quadrangularis Stein.) 111,426

( ' ' rugosus Hisinger) Ill, 426

( " rogersi N. & P.) V.569

scitulus M. & W 11,280*

splendens N. & P 11,321; V.569

subaculeatus N. & P 111,413

swallovi Shum 111,462

( " tubulospinus McCh.) V.569

( " wabashensis N. & P.) 11,321; V.569

Proetus Steininger Ill, 460

ellipticus M. & W.. 111,460*

' ' swallovi Shum III. *62

Protaster Forbes V.509

gregarius M. & W V.509*

miltoni Forbes V,510

Protocrisina Ulrich VIII.369,405

exiguaUlr VIII.369,405*

Protolycosa Roemer 111,568

Protonopsis Bart : 11,139

Protospongia Salter VIII.216,237

fenestrata Salter VIII.237

(?) minor Matthew VIII,237

var. distans Mat VIiI,237

' ' tetranema Dawson VIII, 237

Protozoa (11,145,233,262); 111,345; V.560; VI,500

Proutella Ulrich VIII,366,403,674

discoidea Prout VIII, 674*

Psammodontidae de Koninck VII,57,197

Psammodus Agassiz 11,36,75,92,107,111; IV,362,370; VII, 171, 197

angularis N. & W 11,107*; VH.222*

cactus St. J. & W VII.217*

" canaliculatus McCoy 11,109; VII.222

GENERAL INDEX. 135

Psammodus crassidens, St. J. & W VII. 218*,220t

glyptus St. J. & \V : YII.209*

grandis St. J. & \V VII, 211*

lovianus St. J. & W TEE, 207*, 217

plenus St. J. & W YII.213*,221

porosus Ac? 11,107*; VII, 199, 209,217, 219. 222

reticulatus N. & W 11,109*; VII.218,224*

rhomboideus N. & W.) 11,110*: YH.184*

rugosus Ag. (?) II, 108*. 110 ; VII, 218

(?) semicylindricus N. & "W 11,109*; VII, 184*

semireticulatus N. & W 11,111

springeri St. J. & W YII,202t*

tumidus St. J. & W VII, 205*

turgidus St. J. & W VII,206*,207t

Psephodus Agassiz VI, 299, 337, 417; Yn,61,63

crenulatus N. \- AY VTI,67,69,74

latus St. J. & W VII.72*

lunulatus St. J. & W VII, 74*

magnus Ag VI, 419; Vn,63,66,69

obliquus St. J. & W VII,66*,72

placenta N. & W VII, 69*

(?) reticulatus St. J. & "W VI, 417*

" (?) symmetricus St. J. & W VII, 71*

(Pteria) morganensis M. & "W V,57tj

""(?) subpapyiacoa M. & \V 111,438

" (?)undulata M. & W 111,456

Pteriida? 11,337

Pterinea Goldfuss 11,339: HI, 338, 3*4. 358, 437, 456

cardiif ormis Hall n, 156

(Monopteria) gibbosa II, 340*

( ) morganensis M. & V." V.576

( " ) negiecta McCh 111,358

retroflexa (Wahlenb.) m,355

" (?) rhomboidea (Hall) 111,355

su bpapyracea M. & W ni, 43 7*

- subplana (Hall) 111,355

thebesensis M. & \V 111,354*

" (?) undulata M. & W m, 456*

Pteronites McCoy 131,338

Pteropoda 111,341; Y,520,541; Vn,325; Vm,134

Pterotocrinus Lyon and Casseday 11,288; Y.559

chesterensis M. &; W n,2b2*,293t

crassus M. & W n,290*,292t

depressus L. & C V.559*

pyramidalis L. &. C JQ.293

Pterygotus Apassiz Ill, 545

(Ptilionella Hall) VIH,368

Ptilodictya Lonsdale VHI, 3 90. 496, 531

( " ) cosciniformis, Nicholson VIII, 532

( " expansa Hall) VIII,391f

( " ) fenestelliformis Nicholson VHI, 526*

lanceolata Goldfuss Vin,391t

maculata Ulrich Vin,317t

magniflca S. A. Miller.. VUI,3iHt

nodosa (HaU) VHI.304

pavonia d'Orbigny Vin,393,671

variabUis Ulrich... VIII, 304t, 317+

136 GENERAL INDEX.

Ptilodictyonidffi Zittell VIII.S46.S90

Ptilopora McCoy VIII, 398,621

acutaUlrich VIII, 622*

cylindracea Ulr ....'. -• VIII, 623*

pauperaUlr VIII, 624*; 11,106*; IV, 374

proutiHall V1II.308.625*

validaUlrich VIII.623*

Ptiloporella Hall VIII.397

Ptiloporina Hall • VIII.397

Ptilotrypa Ulrich VII1,393,531

obliquata Ulr VIII,393,531*

Ptychodus Pander IV.374

(Binodus) calceolus N. & W : 11,106*; IV.374

obliquus Pander

polygyrus VIII, 4t

(Ptychonema Hall) VIII.379

Pulvillus Carter VIII, 218

Pychnodonts II, 89

Badiopora d'Orbigny VIII.340

Eamipora Toula • Vin, 360.898

Bana Linnaeus 11,138

Baniceps Wyman , 11,140

lyelli Wyman 11,137

Baphidistia Carter • VIII. 218

Baphistoma Hall 111,316

lentieularis (Sbv.) 111,316*

Eauffella Ulrich VIII, 212, 217, 236

flliosaUlr VIII, 236

palmipes Ulr VIII.236

Beceptaculites Defrance 111,301,345; VI.500; VHI.217,238

formosus M. & W VL500*

globularis Hall Ill, SOI*

oweni Hall 111,302*

sp. indet. 111,301*

Beceptaculitidae Hinde VIII, 238

Beniera Carter VIII.218

Eensseljeria Hall 111,401; VI.502

condoniM. Ch 111,401*

( " )elongata (Vanuxem) 111,402

ovalis Hall 111,401

Beptaria Bolle VIIL368

Beptilia 11,135

Betepora Imperato VIII, 612

( " )angulata Hall VIII.639

( " )asperato-striata Hall VIII,399,639

( " )diffusa Hall VIII,399

( " ) flustriformis Phillips VIII,398

laxa Phill 11,423

( " ) trentonensis Nicholson VIII, 899, 639

( " ) undata McCoy VIIL640

Bhabdaria Billings VIII.216,240

fragile Bill VIII.240

furcata BiU VIII.240

Bhabomeson Young and Young VIII, 364, 402

gracile (Phillips) VIII.402

rhombiferum (Phillips) VHI,661

GENERAL INDEX. 137

Bhabdomesontidae Vine.- . Vin,36S, 401

(Rhinidictya Ulrich) VUI, 8 88, 492, 520

Bhinodus Newberry and Worthen 11,106; IV.874

calceolus N. & W n,106*: IV.374

Bhinopora Hall .VULI, 388

verrucosa Hall VH3.388

Bhinoporidse Ulrich (provisionaD "VTH,388

Rhizodus Owen ...EI.18: IV.349

occidental N. & W II,19t; IV,349,P1. iv.flg. 1*

reticulatus N. & \V jy, 349*

Rhodocrinidas . . . vni.180

Bhodocrinus Miller H.217,219; HI.476; VII,305; YIU.180

barrisi Hall 111,478

coxanus Worthen VII, 305*

kirbyi W. & Sp Vm.l72,180*.183,184,187

nanus M. & W 111,476**; Vm,182*

polydactylus Worthen Yn, 305*

watersianus W. & Sp Vni,184*

Rhombocardia M. & W 111,441

Bhombopora Meek Vni, 402, 647

angustata Ulrich VIII, 652*

? asperula Ulr VHI,365.636*

attentiata Ulr Vm,655*

crassa Ulr Vni.365,447

decipiens Ulr Vm,365, 667*

dichotoma Ulr Vin,365, 650*

elegantula UJr YIH, 447

exigua Ulr Vm,651*

gracilis Ulr vm, 651*

granulif era (Hall) VUI, 647

humilis Ulr Vm,650*

incrassata Ulr VUI, 364, 652*

lepid odendroides Meek VIII, 402, 651

lineinodis Ulr VTTT, 649*

minor UTr Vin.364,659*

multJ pora Fcerst e VUI, 634

nicklesi Ulr VTH, 661*

persimilis IHr VUI, 659*

simulatrix Ulr VUI,365, 657*

? spiralis Ulr Yin, 656*

subannulata Ulr Vm, 364, 648*

sulcifera Uh- , Vm,649*

tabulata Uh- TEH, 364, 658*

tenuirama Uh- VIII, 660*

transversalis Ub- VJLLL, 654*

varians UTr Vm, 653*

wortkeni Uh- : Vm, 655

Bhopalonaria Ulr VIII, 3 67

venosa Ulr VIII,367

Bhynchonella Fischer H.153; DI,394,450; V.571; VUI,104

f ormosa Hall 111,379

illinoiensis Worthen Tin, 104*

missouriensis Shum II, 153* ; ni, 450*

osagensis Swall % V.571*

ottumwa White ,, Tin, 132,

-18

138 GENERAL INDEX.

(Rhynochonella parvini M. Ch.) 11,251

pugnus (Mart.) 11,154; 111,452

' ' reniformis II, 154

speciosa Hall Ill, 394

striato-costata M. & W Ill, 452

( " ) subtrigona M. & W 11,251

wilsoni Sby VIII, 104

Kibeiria Sharpe VIII, 241

calcifera Bill VIII, 241

longiuscula Bill VIII, 2 11

Saccocrinus Hall 11,151; 111,347; V.395

" (?)amplus M. & W 111,4701*

christyi (Hall) 111,347*

infelix (Winch. & Marcy) 11,210; 111,349

marcouanus (Winch. & Marcy) 11,210

sacculus M. &W 111,319

Saccospongia Ulrich VIII,212,217,239

danvillensis Ulr VIII, 239

rudis Ulr VIII.239

Sagenella Hall 11,415; VHI,368

S alamandra Laurenti II, 139

Sandalodus Newberry and Worthen 11,102,111; IV.362,369; VII,61,1S4

anguftus N. & W 11,103*

( " . ) carbonarius N. & W 11,104*; IV.369; VII.182*

complanatus N. & W VII.184*

( " crassus N. & W.) IV.369*; VII.188*

( '•' grandis N. & W.) 11,92,105*; VII;184*

laevissimus N. & W 11,104*; VII,184,186*

( " )parvulusN. & W 11,102*; VII.107*

spatulatus N. & W 11,103*: VII.188*

sp. indet VII.187*

Sanguinolites McCoy VIII, 129

(?) burlingtonensis Worthen V1II.129*

(?) multistfiatus Worthen VIII.129*

randolphensis Worthen VIII.130*

(?) subarcuatus M. & W 111,537

Scalaripora Hall VIII, 387,507

approximata Ulr VIIL508*

scalariformis Hall VIII.387

separata Ulr VIII, 507*

Scalites angulatus Conr Ill, 317

Scaphiocrinus Hall 11,237; III.488; V.407,492.534,550,561; VI.519; VIII.195

abnormis Worthen VI, 519*

( )ffiqualis Hall V.494*; VII.282

bayensis M. & W V.550*

carbonarius M. & W V.562*

carinatus Hall V.409

olio M. & W -. V.408*

coreyi M. & W V.494*

decabrachiatus Hall V, 534,551

decadactylus M. & W II,233*,240t: V.496; VII, 276

delicatus M. & W V.407*

depressus M. & W V.492*

dichotomus Hall V, 409, 415

divarica'tus HaU 11.238

elegantulus W. & Sp VIII,195*

GENERAL INDEX. 139

Scaphiocrinus flscellus M. & W V.418,424*

globosus W. & Sp ." VIII.196*

halli Hall III. 491; V.422

hemisphaericus (Shum.) V.561*; VI.527

huntsvillce Worthen V, 534*

( " Jinternodius Hall VII, 286, 294

juvenis M. & W V.417*

mac-adamsi Worthen V, 495*

macrodactylus M. & W V.415*

nanus M. & W V.408.423*; Vin.195

notabilis M. & W V.410*

( ) orbicular is Hall VIII.97

penicillus M. & W V.414*

randolphensis Worthen V, 551*; VH.297

rudis M. & W V.412*

msticus White V.409

scalaris M. & W V. 418. 421*. 425

simplex Hall 11.181; V.419

( ) spinibrachiatus Hall ...Ill, 489. 491; V.413; VIII.193

striatus M. & W V.418*

(?) subimpressus M. & W V. 416

subtumidus M. & W 11,178

tenuidactylus M. & W III,490t*

tethys M. & W V.419*

unicus Hall V.493*; VI.519*; VII.273,278

( } -wachsmuthi M. & W III,488t*; V.409; VIII,193

whitei Hall 111,491

sp. indet VIII.162

Sceloporus Wiegman 11,138

Scenellopora (Jlrich VIII,368

radiata Ulr VHI.368

Sceptropora Ulr Vm,363,400

facula Ulr VIII, 401t

Schizoblastus Etheridge and Carpenter VII.350

melo (O. & Sh.) VII.349

sayi Shum VII.350

Schizodus King 11,301,345; in.340; V.579; Vni,107

amplus M. & W V.579*

chesterensis M. & W 11,301*; VIII.108

" (?)circulus Worthen VIII.109*

curtus M. &W V.582*

depressus Worthen VIII.109*

( " magnus Worthen) VIII.107*

' ' nauvooensis Worthen VIII, 108*

obscurus Sby 11.301,346

oceidentalis (Swall.) V.580

perelegans M. & W V.581

randolphensis Worthen VIII, 110*

rossicus Vern V.PL xxvi.flgs. 17 and 18*

' ' tmncatus King II, 346

ulrichi Worthen VIII.110*

varsoviensis Worthen VIII. 107*

wheeled Swall VIII, 110

" (?)sp. indet H.345*

Schizopoda

Schoanaster Meek and Worthen 11.277 ; in, 499

140 GENERAL INDEX.

Schcenaster flmbriatus M. & W 11,278*; 111,500

wachsmuthi M. & W 111,499*

Sderocephalus Goldfuss 11,140

Scorpionidae HI, 560

Sebargasia Steinman VIII.218

Sedgwiokia (Sanguinolites ?) subarcuata M. & W 111,537*

Selachii VI, 472,483

Selenopora Hall VIII.384

circincta Hall VIII,384

Seliscothon mantelli Goldf VIII, 225*

Semicoscinium Prout VIII, 395,555

acmea (HaU) VIII.534

( " ) infraporosum Ulr VIII.559

' ' permarginatum (Hall) VIII, 556

' ' planodorsatum Ulr VIII, 555*

rhombicum Ulr VIII, 556*

rhomboideum Prout .' VIII, 395, 555, 557

semirotundum (Hall) VIII.556

thyene (Hall) VIII,534

sp. indet VIII,, PL liv.flg. 0*

Septopora Prout VIII,397,626

biseralis Swallow VIII.631*

biserialis var. nervata Ulrich VIII,632*

cestriensis Prout VIII, 398, 628*

( " cestriensis M. & W., not Prout) V.P1. xxiv.flg. 14; VIII,628,629

decipiens Ulrioh VIII.630*

delicatula Ulr VIII.634*

pinnata Ulr VIII.633*

robustaUlr VIII, 633*

var. intermedia Ulr Vni,634*

subquadrans Ulr ....VIII.629*

Siluridse 11,125

Simplegas Montf ort '. II, 162

Siphonella Hagenow.. VIII.364

(Siphonia excavate Golf.) VI, 499

( ' ' stipiteta Hisinger) VI.499

Solarium Lamarck .' 11,354

( " ) antiauum d'Orb II, 159

Soleniscus Meek and Worthen .- 11,368,383

typicus M. & W 11,384*

Solenocaris Meek VIII, 153

sancti-ludovici Worthen VIII, 153*

Solenocheilus Meek and Worthen VIII, 150

capax M. & W V.545

coUectumM. & W V.544*; VIII, 151

indianense Worthen VIII, 150*

leidyi M. &W : V.545

Solenomya Lamarck 11,349; VIII, 131

" (?) iovensis Worthen VIII, 132*

monroensis Worthen VIII, 131*

radiata M. & W II, 349*

varsoviensis Worthen VIII, 131*

sp. indet V,P1. xxvii.flg. 1*

Sollasia Steinman VIH.218

Spatiopora Ulrich VIII, 381

* ' aspera Ulr VIII, 381

GENERAL INDEX. 141

Sphaerexochus Beyrich VI.510

romingeri Hall YI.510*

Sphaerocrinus Boemer 11,214

( M. & W.) 11,214

( JconcavuB M. & W 11,215*

Sphaerolites Hinde VHI,228

( " nfcholsoni Hinde) Vm,227,278

Sphenopoterium Meek and Worthen 11,145,233,262

compressum M. & W 11,234

cuneatum M. & W 11,262*

enorme M. & W 11,146*

••' var. depressum M. &. W 11,146*

obtustim M. & W n.233*

Sphragiopora Ulrich Vm,398,638

paratitica Ulr VHI,399,638*

Sphragioporidse Uir VHI,362, 398

Spinax Cuvier II, 121

Spirifer Sowerby 11,155,298; m.384,398,414.«3,530; Y.572; VI. 521; VIH.105

arrectus Hall DI,399

cameratus Morton V.573*; VI.522

(Young) V.P1. xxv.fig. 6*

cooperensis Swall n, 155*

cuspidatus Sby IH.530

discors Phill H.298

engelmanni M. & W HI, 398*

fastigatus M. & W VI.521*

" fornlculaHaU in, 433*

f ultonensis Worthen V, 572*

glaber (Martin) Sby 11,298

var. contractus M. & W n,298*

hemicyclus M. & W 111,399*

( " ) hemiplicatus Hall 11,322

"(?)lamarcki (Fischer) 11,323

laevigatus Bxish 11,298

lineatus (Martin) n. 156

linguifer PhiU H.298

littoni Swall VIU.132

mosquensis Fisher 11,323

multigranosus Worthen VIII, 105*

neglectus Hall VI, 523*

oblatus Sby 11,298

(Trigonotreta) paradoxus (Schloth) 111,415*

( ) perextensus M. & W m,414*

perlamellosus Hall HI, 384*

pinnatusOw 111,415

var. ligus Ow 111,415

( " ) planosulcatus Phill 11,254

( " planoconvexus Shum.) 11,156

propinauus Hall 111,530*

segmentatus HaU IH,4S4

semiplicatus Hall 11,155

striatus Martin 111,532; VI.523

subcuspidatus Schnur Ill, 434

( " " Hall) ni,4S4

suborbicularis Hall VI.523*

" subttndiferus M. & W 111,434*

142 GENERAL INDEX.

Spirifer symmetricus Phill 11,298

" undiferus Eoem 111,435

urei Flem II, 156

' ' varicosus Hall Ill, 400

Spirigera d'Orbigny 11,254

( ' ' ) subtilita Hall V.570

Spirorbis carbonarius Dawson II, 462*

SgongiEe 11,145,233,262; 111.301,344,419; VI, 491,499; VIII, 211 ,233, 245, 255

Squaloraja polyspondyla Ag 11,71

Squalus Linnaeus VI, 276

Steganocrinus Meek and Worthen 11,150,195; 111,474

araneolus M. &W 11,198*

" (?) concinnus Shum V.341

pentagonus (Hall) 11,196+; III,474*,519

sculptus (Hall) II, 197t

Steganopora d'Orbigny VIII, 345

Steganoporella Smitt VIII, 345

Stellipora Hall VIII, 374

antheloidea Hall VIII.375,423

Stemmatodus St. John and Worthen VI, 328

bicristatus St. J. & W VI,331*,334

bifurcatus St. J. & W VI, 330*

cheiriformis St. J. & W VI,330*,334

compactus St. J. & W VI, 334*

keokuk St. J. & W VI, 334

simplex St. J. & W VI,332*,335

symmetricus St. J. & W VI.333*

(Stenocisma Hall) 111,377-380

Stenopora Lonsdale VIII, 375, 436

americana Ulr VIII, 309t. 437*, 438, 439

" var. varsoviensis Ulr VIII.437*

angularis Ulr VIII, 439*

carbonaria (Worthen) VIII, 445*

" var. conferta Ulr VIII, 445*

var. maculosa Ulr VIII, 445*

cestriensis Ulr VIII.442*

emaciata Uh- VIII,438*

( " flbrosa Goldfuss) " VIII.288

intercalaris Ulr VIII, 439*

intermittens Ulr VIII, 440t

meekana Uh- VIII, 443*

montifera Uh-. , VIII.438*

( " polymorpha Prout=S. tuberculata Prout) VIII, 444, 671

ramosa Ulr VIII, 36? , 442*

rudis Uh- VIII, 444*

?signata Uh- VIII,365,446*

tasmaniensis Lonsdale VIII, 375

tuberculata (Prout) VIII,315t, 438. 441*+

Stenopterodus St. John and Worthen VII, 61, 81, 100

elongatus St. J. & W VII.106*

parvulus (N. & W) VII.107*

planus St. J. & W VII.102*

sp. indet VII, 105*

Stenoschisma Conrad Ill, 338

Stictopora Ulrich (Hall, 1847) VIII.388,491

» GENERAL INDEX. 143

(Stictopora Hall 1886) Vin.491

( " ?) acuta Hall. . .'. Vm,491

( " ! crenulata Hall YIEI.492

( " ) cre-cens Hall YIII.492

( ) elegantula Hall Vni,491

fenestrata Hall VHI,388,492

) gilberti Meek ; V1II.492

glomerate Hall YIH,491

) incisurata Hall Yin,492

( " ) invertis Hall Vm,492

labyrinthica Hall YIII,491

) limata Hall Vni.492

( " ) linearis Hall VHI,492

( " ) meeki Nicholson ? Vm,492

mutabilis Ulr Vm,304t

nicholsoni (Ulr.) VIII, 492

i ovata Hall Vni,492

) ovatipora Hall Vin,492

) palmipes Hall Vni,527

) perarcta Hall Yin, 492

) punctipora Hall VTQ,394t

ramosa Hall Vin,491,492

( " ) reetilinea Hall Vin.492

( " ) rigidaHall Vm,492

i " ) semistriata Hall Vm,492

( " ) shaflferi Meek VHI,:«3

( " ) similis Hal! VIH,393,394t

sinuosa Hall VTH, 492

( " ) subrigida Hall Vm.492

( " ) sulcata Winchell VIII, 492

( " ) trilineata Hall Vm,492

( " ) tumulosa Hall VHI.492

) vermicula Hall VDI,492

Stietoporella Ulrich VIH.394,532

basalis Ulr VHI,532*,727

interstineta Ulr Vni,394

(?) undulata Ulr VIH, 533*

Stictoporidae Ulrich (emended) Vm,347, 388

Stictotrypa Ulrich Vm,349,393

punetipora (Hall) \T:n,394t

similis (Hall) VHI, 393,394t

Stomatopora Bronn Vni, 367

dichotoma Lamx VHI,367

Straparollus Montfort 11,158,285,302,362; V.604; VHI.142

acutus (Sby.) n,363

antiquus (d'Orb.) H.159

dionysii Montf IE. 158

lens (Hal!) H.159*

pentangulatus (Sby.) EE, 286

pernodosus M. & W V.604*

planodorsatus M. & W n, 285, 302*

rugosus Sby V, 606

( •• " Hall) -. V.606

similis M. & W 11,285*

var. planus M. & W 11,286*

subquadratus M. & W Y,605*

144 GENERAL INDEX.

Straparollus subrugosas M. & W V, 607*

subumbilicatus Worthen VIII, 148*

umbilicatus M. & W 11,285,362*; VIII.142

' ' varsoviensis Worthen "VIII, 142*

Streblodus Agassiz IV, 365

coleiAg VII.92

( " oblongus Ag.) VII.92

' ' tenerrimus Eon VII, 83

Streblopteria McCoy II. 332

laevigata McCoy II, 333

pulchella McCoy 11,333

(?) tenuilineata 11,334*

Streblotrypa Ulrich VHI,403,665

distincta Ulr VIII, 669*

major Ulr VIII, 666*

nicklesi Ulr VIII, 403,667*

radialisUlr VIII.667*

subspinosa Ulr VIII, 668*

Streblotrypidae Ulrich VIII.365,402

Streptacis Meek (?) V,596

whitefieldi Meek V.596*

Streptorhynchus King 111,336

<?) propinquus M. & W 111,351

( " ) subplanus (Conr.) 111,349

Streptosolen Ulrich and Everett VIII.217,222,235,257,272,273

obconicus U. & E VIII,235,274*

Streptospongia Ulrich VIII.217,240,255

labyrinthica Ulr VIII.240

Streptostylus Conrad II, 869

Striatopora Hall : 111,368

flexuosa Hall 111,370

iovensis Ow 111,369

linneana Bill 111,370

missouriensis M. & W 111,369*

( ', rugosaHall) 111,369

Stricklandia Billings 111,402; VI.502

davidsoni Bill VI, 503

deformis M. & W VI, 502*

elongata (Vanux.) 111,402

var. curta M. & W 111,402*

Strobilosponeia Beecher VIII, 217

Stromatoporoidea VIII, 216, 221, 282

Strophodonta HaU 111,374

1 ' cavumbona Hall Ill, 374*

rectilateralis (?) M. & W Ill, 375*

Strophodus Agassiz 11,76,83

' ' tenuis Ag II, 81

Strophomena Baflnesque 111,335,374, 411,426

carinata Conr Ill, 427

cavumbona Hall Ill, 374*

( " depressa Sby.) 111,337

( " laticosta Sandb.) ..111,427

( " pileopsis Bum.) 111,426

planumbona 111,336

rhomboidalis Wilck 111,366, 426*

(var. analoga Dav.) > Ill, 426

GENEEAL INDEX. 145

Strophomena rugosa Raf 111,336

subplana Conr Ill, 349

unicostata M. & W HI, 335*

(Strophodonta) sp. indet '. in, 411*

Strophostylus Hall ni, 404

(?) cancellatus M. & W HI, 404t*

" (?) ventricosus (Conrad) III. 405*

Strotocrinus Meek and \\forthen 11,150,188 : V,339,347

aegilops (Hall) II.19Q; V,349,355,357

(Physetocrinus?) asper M. & W V.351*

asperrimus M. & W. V.349*

(Physet.) cancellatus (Hall) V.349

( " elavis Hal) ..V.349

(Physet.) dilatatus M. & W V.363*

ectypus M. & "W V.353*

erodus (Hall; n, 190

(?)glans (Hall) V.349

glyptus (Hall) 11,190; V,349,353,355,357

insculptus Hall V.349

liratus (Hall). n,190; V.347,349, 355*

var. (?) subumbrosus (Hall) V.349

(Physet) ornatus (Hall) V, 349

( " } " var. (?) senarius (Hall) V.349

perumbrosus (Hall) II, 188t ; V.339, 347,349, 357*

regalis (Hall) II,189,191t,192t*,194t; V.349

(Physet.) reticulatus (HalP V.349

rudis (Ha.l) V.349

(Physet) senarius (Hall) V.349

subumbrosus (Hall) 11,190 ; V, 349

(Physet.) subventricosus M. Ch V,349,364

teuuiradiatus (Hall) V.349

tholus (Hall) V.349

umbrosus (Hall) .....11,190; V,349,360*

(Physet.) ventri?osus (Hall) V.339,347, 348

sp. indet V.P1, vii.flg. 3*

Strotopora Ulrich Vni, 383,486

dermata Ulr VIII, 488*

foveoataUlr Vni,383,487*

perminuta Ulr Vin, 487*

Strotospongia Ulrich and Everett VET, 215, 217, 239, 255, 276

maculosa U. & E YHI,239,277*

Stylonurus Page ni,545

Subulites Conrad 11,361,373; VI, 495

(Polyphemopsis) brevis M. & W HI.362*

elongatus Conr 111,361

inflatus M. & W VI.495*

( " ventricosus Hall) 111,362

Synbathocriuus Phillips 111,465; V.324.4,??: VI.514

brevis M. & W V.439*

dentatus O. & S V.438,439

papillatus HaU V, 438,439

robustus Shum VI, 514*

wachsmuthi M. & W IH,465*; V.437*

wortheni Hall V, 438,439

Synocladia King VIH,398,627

( " )biserialis SwaUow V.P1. 24,flg. 15*; Vni,631

—19

146 GENERAL INDEX.

Synoeladia virgulacea King VIII.398,627

( " virgulacea? Swallow) VIII.631

Syntrielasma Meek and Worthen 11,321; V.571

(?)andii (d'Orb.) 11,323

(?)gaudreyi (d'Orb.) 11,323

hemiplicata (Hall) II,322t,323,324+; V.571*

(?)lamarcki (Fischer) 11,323

Syringelasma Ulrich VIII,218,222,235,250,705

wortheni Ulr VIII.235,250*

Syringothyris Winchell.

ciispidata (Sby.) 111,532

" propinqua (Hall) 111,532

Teenlodietya Ulrich VIII,393,528

cingulata Ulr ¥111,304+, 530*

frondosaUlr VIII, 529*

ramulosa Ulr VIII,393,528*

var. burlingtononsis Ulr VIII. 529*

subrectaUlr VIII. 530*

Taeniodus de Koninck VII. 61, 75

contortus Kon VII, 74

fasciatus (N. & W.) VII.76*

obliauus St. J. & W VII.78*

regularis St. J. & W VII.77*

Taeniopora Nicholson VIII.386,504

exiguaNich VIII.505

occidentalis Ulrich VIII, 505*

pemniformis Nicholson VIII,386,505*

Talarocrinus Wachsmuth and Springer VII, 314

ovatus Worthen VII.314*

sexlobatus (Shum.) VII. 315

Tanaodus St. John and Worthen VI, 367

angularis (N. & W.) 11,34,55*; VI, 357, 368, 375

bellicinctus St. J. & W VI,370,376*,379,381

depressus St. J, & W VI, 371, 378*, 381

grossoplicatus St. J. & W VI.375*

obscurus (Leidy) VI.368

polymorphus St. J. & W VI, 372, 374, 377, 380*

praenuntius St. J. & W. VI,371*,381

pumilus St. J. & W VI, 369*. 379, 381

sculptus St. J. & W VI,373*,381

sublunatus St. J. & W VI, 368*

Taxocrhras Philh'ps 11,268; 111,421,495; V.399; V1I.308; VIII, 197

agassizi (Hall) 11,270; 111,495

var. giganteus M. & W 111,495*

communis (Hall) 11,270

egertoni Phillips II, 270

fletcheri Worthen VII.308*; VIII.197*

giganteus (?) M. & W ' 111,495*

graciUs M. & W Ill, 4211*

intermedius W. & Sp VIII,199*

interscapularis Hall Ill, 422

juvenis Hall 11,271

kelloggi (Hall) ; , 11,270

macrodactylus Phill II, 270

" nobilis Kon. & Leh 11,270

( " ) norwoodi M. & W ...11,243,245*

GENERAL INDEX. 147

Taxocrinus nuntius (Hall), 11,270

semiovatus M. & "W 11,272*

thiemei (Hall) 11,271 ; V.399*

( )wortheni (Hall) 11,270*: V,496*,553

Tectulipora Hall VIII, 679

" (?)gothlandicaUlrich VIII, 678*

Telerpeton Mant 11,140

Tellinomya Hall 111,307

alta Hall Ill, 309*

contracta (Salter) 111,308

nasuta Hall Ill, 309

ventricosa Hall 111,307*

Temnocheilus McCoy 11,162; V, 524, 543, 608; Yin, 151

coxanum M. & W V.643*; Vni,151

latum M. & W V.608*

niotense M. & W V, 522

scottense Worthen VITE, 151

win-lowi M. & W V.609*

Tentaculites Schlotheim II, ,341

distans Hall 111,343

elongatus Hall 111,342

( flexuosus Hall) IH,342

incurvus Shum TTT, 342

oswegoensis M. & W Ill, 342*

sterlingensis M. & W 111,343*

tenuistriatus M. & W Ill, 341*

Terebratula Llhwyd V.572; Vni,102

( ' ' afflnis Sby.) 111,432

andii d'Orb 11,323

( " ) aspera Schloth 111,430

bovidens Morton V.572*

gaudreyi d'Orb 11,323

geniculosa M. Ch V.572

paradoxa Schloth Ill, 415

( ' ' prisca Schloth.) Ill, 432

• rowleyi Worthen VIII.102*

schlotheimi Buch 111,379

( " )subtilita Hall V.570

( " sp. d'Orb.) n,321

Tesseles Desor II, 225

Tethyopsis Zittel VOI,245

Tetradium Dana in,346

Tetracladina Zittel VIIT,223,225,226,231,234

Tetractinellida Marshall VIII, 220,233

Tetradecapoda 11,399; 111,549

(Thallostigma Hall VIH, 382, 475

(Thamni^cida; King) VHI.358

Thamuiscus King VDJ,397,606

( " )cisseis HaU VIII.399

crassus (Lonsdale) Vm,607

dichotoma HaU V1H.607

divaricans Ulr Vin,357,608*

dubius (Schlotheim) VIII,357,397,60ti

furcillatus Uh- VIII,609*,637

gracilis Vine VHI.610

( " ) niagarensis Hall '. VIII,399,607

octonarius Ulr Vm,611*

148 GENERAL INDEX.

Thamniscus ramulosus-TTlr Till, 357, 607, 610*

( " var.) sevillensis Ulr VIII,610*,727

sculptilis Ulr , .'..... YIII, 608*

serialls Waagen and Pichl VIII, 608

sevillensis Ulr Vm,610*,727

Thamnodictya Hall VIII, 237

newberryi Hall VIII,237

Thamnotrypa Hall VIII.387

Trinacodus St. John and Worthen VI.280, 289

duplicates (N. & W.) 11,61*; VI, '.89

incurvus (N. & W.) 11,62*; VI.290

nanus St. J. & W VI, 289*

Tomodus Agassiz VII, 171, 191

convexus Ag '. VII, 171,177,179

" (?)limitaris St. J. & W , VII.173*

Trachydomia Meek and Worthen 11,364, 3(i6; VIII.146

brevis (Sby) II, 364

•marias (Murch.) II, 364

npdosa M. & W 11,364,366*

" hollidayi M. & W 11,367*; VIII.147

nodulosa Worthen VIII, 146*

wheeleri Swall 11,364; V.595*; VIII.147

Trachypora Edwards and Haime VIII, 81

austini Worthen VIII,81*

ornata Horn VIII.81

Trachyum Billings VIII, 211, 216, 241

cyathiforme Bill , VIII.241

rugosum BiU VIII.241

Tremataster Worthen and Miller VII, 330

difflcilis W. &M VII.330*

(Trematocrinus Hall) 11,217

( ) papillatus Hall 11,219

( " ) reticulatus Hall 11,219

( " ) tuberculosus Hall 11,225

( ', ) typus Hall 11,219

Trematodiscus Meek and Worthen • 11,161

trisulcatus M. & W .'.11,162*

Trematopora Hall .' VIII.373,418

calloporoides Ulrich VIII, 420*

( " )cofcstricta Hall VIII.468

debilis Ulrich ' VIII, 419*

( " ) granulif era HaU , ; VIII.647

( " )n:inuta Hall VIII.645

?nitida Ulrich VIII.419*

primigenia Ulr VIII,419,420

tuberculosa Hall VIII, 374,418

( " ) venusta Hall VIII.468

Trematoporidse Ulrich ^ VIII.340, 373

Trematospira Hall 111,381

(?) imbricata Hall 111,381*

Trepostomata UMch VIII, 337, 369

Tretoceras Salter 11,307

Trichospongia Billings VIII, 211, 216, 241

sericea Bill ...VIII.241

GENERAL INDEX. 149

Trigonodus Newberry and Worthen 11,111

( " major N. & W.) 11.112*; vn,184*

minor N. & W H, 112*

Trimerella Billings 111,551

Tricoelocrinus Meek and Worthen V.507; VI.521

obliquatus (Roem.) VI, 521

varsoviensis Worthen : VI.521

woodman! M. & W V, 506*

(Trigonotreta Koenig) 111,384,398,414

( ) engelmanni M. & W Ill, 398*

( ) hemicychis M. & W 111,399*

( " ) oblata (Sby.) Bronn n,298

( ) paradoxa (Schloth) 111,415*

( ) perextensa M. & W HI, 414*

( ) perlamellosa (Hall) Ill, 384*

( ) striata Martin 111,532; VI.523

Trilobita. 111,299,320,363,390,416,447,460; V.525,612; VI.497

Trimerella Billings Ill, 351

" (?) conradi (Hall) 111,351

TrochacUeon Meek 11,369

ellipticus (Zekeli) H.368

obtusus (Zekeli) 11,368

reynauxianus (d'Orb.) II, 368

Trochus Linnceus IH,316

( " ) lenticularis Sby m,316

( " ) missonriensis Swall 11,36V

Trochonema Salter 111,314

pauper Hall in,361

umbilicatum (Hall) HI, 314*

Troostocrinus Shumard V, 607 ; VII.349,363

reinwardti Troost VII, 357

(?) woodman! M. & W V.506*

Tropidodiscus curvilineatus (Conrad) 11,160

Tropidoleptus Hall HI. 427

carinatus (Conrad) Ill, 427*

Tropidopora Hall <. VIII,402

Trygon Adanson VI.312

Tubuliporidse Busk VIII,3t>0,367,368,688

Turbonilla Risso 11,377

Turritella Lamarck 11,382

" (??) stevensoni M. & W 11,382*

Unitrypa Hall Vni,353,356, 396.534, 679

lata Hall VHL396

(Uperocrinus Meek and Worthen) 11,147,150,151

Uphantaenia Vanuxem VICE, 216,237

" chemungensis Vanux Vin,237

dawsoni Whitfleld. Vm,218

Vanuxemia Billings . ...in,297

dixonensis M. & W '. 111,297*

Vaticinodus St. John and Worthen , VH.ei, 80

" (?) carbonarius St. J. & W VII.88*

discrepans St. J. & W VII.81,83*

" (?; lepis St J. & W VH.88*

" (?) similis St. J. & W VH.86*

" (?) simplex St. J. & W VIL84*

vetustus St. J. & W VH.81,82*

150 GENERAL INDEX.

Venustodus St. John and Worthen VI, 339, 344

argutus St. J. & W , VI.352*

leidyi St. J. & W VI.346,348,350*

robustus St. J. & W VI,345*

tenuicristatus St. J. & W VI.348*

variabilis St. J. & W VI, 346*

Vertieillites DeFraiice VIII, 280

Vesicularidae VIII, 434

Vineularia DeFrance VIII,615

Vincularidaj ; VIII, 363,301

Woodocrinus deKoninck Ill, 478

Worthenopora Ulrich VIII.366,403,669

spatulata (Preut) '. VIII.670*

spinosa Ulrich VIII, 403,669*

Xenorhachia 11,135

Xestorrhytias Meyer — 11,140

Xiphosura 11,393; 111,544

Xystracanthus Leidy VI, 450,457,468

acinaeiformis St. J. & W VI.459*

anceps (N. & W.) VI,458,460

arcuatus Leidy VI, 457

mirabilis St. J. & W VI, 458*

Yoldia Moller n,282

" (?) levistriata M. & W 11,282*

Zaphrentis Baflnesque 111,410; VIII. 71, 132

calcariformis Hall VIII, 74*

carinata Worthen VIII, 75*

centralis E. & H VIII, 72*

chesterensis Worthen VIII73*

cliff ordana E. & H VIII, 75*

cylindracea Worthen VIII, 78*

dalei E. & H VIII, 71*

illinoiensis Worthen VIII, 77*

lanceolata Worthen VIII, 76*

parasitica Worthen VIII, 79*

pellensis Worthen VIII, 74*

reversa Worthen VIII, 78*

spergenensis Worthen VIII, 77*

(spinulifera Hall) VIII, 71

spinulosa E. & H VIII, 73*

ulrichi Worthen VIII, 76*

varsoviensis Worthen VIII, 78*

sp. ind^t Ill, 410*

Zeacrinus Troost 11,181,185,216,237,240,312; V, 426, 490, 534, 547, 563; VII,302; VIII, 91

acanthoporus M. & W '. V.563*

' ' arboreus Worthen V, 534*

armiger M. & W V, 547*

asper M. & W y, 439*

bifurcatus M. Ch 11,241

cariniferus Worthen V, 535*

compactilis Worthen V, 536*

concinnus M. & W — V, 490*

' ' coxanus Worthen '. yn, 302*

" (?) crassus M. & W II, 314*,315t

GENERAL INDEX. 151

Zeacrinus discus M. & W 11,312*; V.565

elegans Hall 11,185

formosus Worthen V, 549*

impressus (McCoy) 11,313

intermedius Hall 11,181

keokuk Worthen VII, 303*

lyraM. & W V.432*

mucrospinus M. Ch 11,313; V, 548, 563*, 565

perangulatus White V,427

pikensis Worthen v VII, 304*

planobrachiatus M. & W II, 240*

ramosus Hall 11,187; V.429

scobina il. & W V,426*,430

serratus M. & W V.428*

spinibrachiatus White V.442

stimpsoni Lyon , VII, 298

subtumidus Worthen '. V.548*

troostanus M- & W II,186*,187t

sp. indet V, PL i, fig. 4*

Zittelella Ulrich and Everett Vin,217,221,222,235,255,257,267,275

" (?)infelix U. & E VIII,271*,274

in sculata U. &E VIII.235,271

lobata M. & E Vin,235,270*

trentonensis Worthen .«. Vin,235,270

typicalis U. & E VIII,235,268*

var. pistilliformis U. & E VIII,235,269*

" subrotunda U. & E VIII.235,269*

" turbinata U. & E VIII,235,269*

Zoantharia 111,804,368,407,420; V.560; VI.525; VIII, 71,216

Zygobatis Agassiz 11,59

Zygospira Hall in,377

concava (Hall) ni,381

modesta (Say) 111,379

subconcava M. & W . . ...111,380*

^

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