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FIGURES AND DHSCRIPTIONS —
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Nes Montreal :
| PRINTED BY JOHN LOVELL, ST. NICHOLAS STREET.

, FOR SALN BY B. DAWSON & SON, 22 GREAT ST. JAMES STREET, MONTREAL ;
as A. H, ARMOUR & CO., TORONTO; JOHN WILEY, NEW YORK; HECTOR BOSSANGE & SON,
PARIS, FRANCE ; SAMPSON LOW, SON & CO., LONDON, ENGLAND.

Pibrary of the Museum
COMPARATIVE ZOOLOGY,

AT HARVARD COLLEGE, CAMBRIDGE, MASS.

Founded by private subscription, in 1861.

GEOLOGICAL SURVEY OF CANADA.

SIR W. E. LOGAN,F.R.S., DIRECTOR.

FIGURES AND DESCRIPTIONS

OF

CANADIAN ORGANIC REMAINS, |

DECADE Iv.

Montreal :
IRVIN LEE MB AYeundOuriON: LOVELL, ST. NICHOLAS STREET.

1859.

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NOTICE.

THE plates of the present Decade were all drawn on stone by
Mr. H. Smiru, at the office of the Survey, and printed by Mr.
MatuHeEws, the well known lithographer of Montreal. The Decade,
like those which have preceded it, will be placed in the hands of
respectable booksellers for sale at a moderate price; and, judging
from the demand for the first one issued, there is good reason to
believe that the whole edition of two thousand copies will be
ultimately disposed of, and that the work will repay the expenses
of publication.

W. E. LOGAN.

MonTrEAL, Ist May, 1859.

PREFACE.

THE following Decade contains descriptions of all the Crinoids of
the Lower Silurian rocks of Canada, of which specimens have been
procured in such a state of preservation as to admit of their being
characterized. Of these, five belong to the Chazy limestone, and
the remainder to the Birdseye, Black River, Trenton, and Hudson
River formations. Altogether we have about fifty species, including
several which have been as yet recognized by their columns only.

Of the thirteen genera to which I have referred these species
two, Ehodocrinus (Miller,) and Glyptecrinus (Hall), occur in the
Silurian rocks of Europe, but none of the species are common to
both sides of the Atlantic. Five of the genera, Heterocrinus,
Glyptocrinus, Dendrocrinus, Lecanocrinus, and Ithodocrinus, have been
found in the State of New York, the first two in the Lower Silurian
and the last three in the Upper Silurian. None of the other eight
genera have been noticed as occurring out of Canada, although it is
highly probable that some, if not all of them, will, in course of time,
be discovered in the Silurian rocks of the adjacent countries.

The most remarkable species is the one to which we have given
the name of Blastoidocrinus carchariedens. This fossil, by the
structure of its ventral surface, is closely allied to Pentremites, the
typical genus of the order Blastoidez, while the arrangement of the
plates in the walls of the lower part of the body, so far as it can
be made out from the imperfect specimens that have been collected,
seems to connect it with the Crinoidez. © The species is interesting,
as it shews us that the organization peculiar to the Blastoidee,

vi. PREFACE.

heretofore not known in rocks of a more ancient date than those
of the higher portions of Upper Silurian, made its appearance or
existed in the Lower Silurian period.

In order to render the work more useful to the student I have
given an introductory section, containing a short account of the
history and structure of the Crinoide.

EK. BILLINGS.

CANADIAN ORGANIC REMAINS.

On the CRINOIDER of the Lower Silurian Rocks of Canada. By
E. Biuuines, F.G.S.

SECTION I.

HISTORY AND STRUCTURE OF THE CRINOIDEX.

Amone the various animal forms that lie entombed in the fossil-
iferous portion of the earth’s crust, none have attracted a greater
amount of attention than the Lily Encrinites, or Crinoids,—that
group of organic remains to which the following memoir is devoted.
Their great abundance in many of the geological formations, the
remarkable shapes of the separated fragments of the skeleton, and
the peculiar flower-like form of the perfect specimens, must have in
all ages excited the curiosity of those whose tastes led them to take
an interest in the varied objects of nature; yet it is only within the
last century and a half that the first correct ideas concerning their
characters began to dawn upon the human understanding. Dr.
Mantel informs us that the circular perforated joints of the column
occur in the tumuli of the ancient Britons, under such circum-
stances as to render it quite certain that our forefathers used them
for ornamental purposes, and perhaps as objects of veneration in
some way connected with the rites of the druidic religion. We
have no reason however to believe that they were at that time
supposed to be of animal origin. In more recent times they were
called, by the peasantry, ‘“ fairy-stones,” ‘St. Cuthbert’s beads,”
“screw-stones,” or ‘‘ pulley-stones”; and in Germany, “ Rosenkranz-
steine,” rosary-beads;” ‘* Hunnenthruenen,” giant’s tears; or ‘‘ Raeder-
steine,”’ wheel-stones ;—some of these names having been suggested
by their form and others originating in the superstitions of earlier
ages. :

It appears that the earliest publication in which has been found
any allusion to the Crinoidez is a book written in 1558 by Agricola,

8 HISTORY OF THE CRINOIDE.

the ingenious German miner who taught that petrifactions were not
the remains of things which once had an actual existence as living
creatures, but simply the shapes of animals generated in the solid
rock by some material principle rendered active by the subterranean
heat. Entertaining such views, he could not be expected to contri-
bute any important assistance in determining the true characters of
fossils which bore no resemblance to any animal then known.
From several passages which occur in the writings of this author
it seems that, previously to his time, naturalists had given to the
different parts of the skeletons of the Crinoids, such as the joints
of the stalk or the flower-shaped body, the names of ‘“ Trochites,”
“ Entrochus,” and ‘‘ Encrinus,” the latter giving origin to the term
‘‘Encrinite,” afterwards used as a general designation for the whole
order. Agricola bestowed the name of Pentacrinus upon the bodies
of that species now so well known as Encrinus moniliformis, applying
it not to the whole of the cup, but to specimens which had lost the
arms. The separated joints of the pentagonal column, which are
somewhat like a five-rayed star, he called Asitroztes or Asteria. It is
scarcely necessary to add that he did not believe them to be animal
remains.

Soon after the time of Agricola the nature of crinoidal remains
became a subject of much discussion, and exercised greatly the
speculative faculties of a host of writers who were more or less
interested in settling the grand problem,— whether or not fossils
were of animal origin. For nearly two centuries many of those
who placed any confidence whatever in the affirmative of the
question still regarded the Crinoids as fossil plants, and contended
that the body with its branching arms was the root; others thought
that the jointed stalks were the petrified vertebral columns of fishes;
while some compared them to the siphuncles of Orthoceratites.
It was not until 1719 that one Rosinus published the opinion that
the Crinoids were the remains of animals closely allied to the Star-
fishes, and endeavored to shew that they were provided with a stalk,
notwithstanding their animal nature. When it is taken into consi-
deration that at that time no living creature with a structure at all
resembling the organism suggested by Rosinus was known, it is
clear that such a view must have appeared quite extraordinary to
most of the naturalists of the age. A correct theory however often
precedes its confirmation, and forty-two years afterwards, or in 1761,
a living encrinite, the Pentacrinus caput-Meduse, was drawn up from
the bottom of the sea with all its parts constructed exactly in

HISTORY OF THE CRINOIDEA. 9

accordance with the ideas of Rosinus. From the date of this
discovery it may be said that the animal origin of the fossil Crinoids
was perfectly well established; but no advance was made towards
their classification, upon principles deduced from the relations of the
different parts of the skeleton, until 1821, when Miller published
his work, “The Natural History of the Crinoidee.’’*

In this work Miller shews that the calcareous plates which
constitute the frame of an encrinite have a quinquepartite arrange-
ment, or consist of five similar sets of plates, which, when spread
out in a plane with the base of the cup for a centre, assume the form
of a star with five rays. He also pointed out how the genera could
be founded upon the various modifications of these rays and upon
the number and position of the other plates, such as the sub-radials
and inter-radials. Up to the present time scarcely any improvement
has been made upon the generic system of Miller. The nomencla-
ture devised by him however for the different plates has been found
inconvenient, and others much more useful in application have been
substituted. The rules for the construction and determination of
genera used by all subsequent authors are essentially those of Miller,
and to him, therefore, belongs the credit of having first correctly
analyzed the skeleton of the Crinoidez.

In June, 1835, the famous discovery of Thompson, that, in the
young state, the Comatule so abundant in some of the existing seas
are true Crinoids, was communicated to the Royal Society.t In that
paper it was shewn that, at certain seasons of the year, the grooves
in the pinnule of the rays of Comatula Europea are filled with eggs
to such an extent that the soft skin which covers the furrow becomes
greatly distended, and that shortly afterwards the eggs are discharged
and myriads of them distributed about upon sea-weeds, shells, and
other marine objects. At first a short, thick stalk, supporting a
small, club-shaped head, which exhibits only obscure indications of
arms, springs from the deposited egg; but soon the stalk increases
in length, the arms are unfolded, and a perfect Crinoid is thus
produced from the egg of a Comatula. The form and structure so

* A Natural History of the Crinoidea or Lily-shaped.Animals, with observations on
the genera Asteria, Euryale, Comatula and Marsupites. 4to. 50 colored plates. By
J.S. Miuier, A.L.S. Bristol, 1821.

t Memoir on the Star-fish of the genus Comatula, demonstrative of the Pentacrinus
Europeus, being the young of our Indigenous Species. By John V. Thompson, F.L.S.,
Deputy Inspector-General of Hospitals. Communicated by Sir James McGrigor, F.R.S.
Edinburgh New Philosophical Journal, volume xx., page 295. .

10 HISTORY OF THE CRINOIDEZ

much resembles the large West Indian Pentacrinus, that it was for
several years thought to be a distinct species of that genus, and was
in consequence called Pentacrinus Europeus. When further advanced
the head, having assumed the form of a Comatula, separates from
the stalk, and during the remainder of its life moves about through
the ocean. As the highly important paper in which this wonderful
fact was communicated to the world ought to be in the hands of
every student of geology, and as also it is difficult to procure, I have
published it entire, with copies of all the original figures, at the end
of this Decade.

The next publication in which any great advance in the knowledge
of the anatomy of the Crinoideze was made appeared, in 1841, in the
‘¢ Transactions of the Royal Academy of Sciences of Berlin.” It was
a paper entitled, ‘On the Structure of Pentacrinus caput-Meduse,”*
containing the observations made by the late Professor J. Miiller
while dissecting a specimen which had been captured in the West
Indian seas and preserved in spirits. In this memoir Prof. Miller
shewed that the grooves which extend from the mouth along the
ventral surface to the bases of the arms, and are thence continued
upon the arms to their extremities, are true ambulacra, closely allied
to those of the Star-fishes. He also greatly improved the nomen-
clature of the different portions of the skeleton.

In 1854 MM. L. DeKoninck and H. LeHon issued an admirable
work, entitled ‘‘ Researches on the Crinoids of the Carboniferous
Formation of Belgium,”’t in which these excellent paleontologists
give a most able review of the whole subject of the skeleton and
classification of these fossils. They have improved the nomen-
clature, until ‘it is now nearly perfect; and they also devised an
ingenious formula, by the use of which all the leading characters of
a genus can be expressed by a few words and figures. I shall make
an application ef this formula to all the Canadian genera. The
work besides includes a catalogue giving the title, date of publication
and author’s name of every book or pamphlet known to contain any
description or allusion to the Crinoids from the time of Agricola, in
1558, up to the year 1854. There are upwards of three hundred

* Uber den Bau des Pentacrinus caput-Meduse. (Abhandlungen der Koniglichen
Academie der Wisenschafften zu Berlin, 1841, page 177.)
} Recherches sur les Crinoides du Terrain Carbonifére de la Belgique. Par L.°

DeKoninck et H. LeHon, suivies d’une notice sur le genere Woodocrinus. Bruxeiles,
1854,

STRUCTURE OF THE CRINOIDEZ. 11

different works noticed ; and to collect so great a mass of authority
must have cost a vast amount of labor.

The above are the most important works containing information
relative to the structure of the Crinoideee founded upon the per-
sonal observations of the authors. The list of books, or periodicals
with articles or papers describing new species or genera, is too
extensive to be given'in this place; and I shall therefore now
proceed to notice in detail the different portions of the skeleton of
the Crinoids, and to explain the meaning of the technical terms used
in the subsequent portion of this memoir.

I. The Column or Stalk.

The column usually consists of along and slender cylindrical stalk,
composed of numerous short joints, so closely articulated together,
that, during the life of the animal, it must have possessed a very
considerable amount of flexibility. It seems probable that in species
where the joints are alternately large and small, as in Glyptocrinus,
there was a greater degree of pliancy than in those instances where
it is formed of thin, equally large circular plates, as in the lower
part of the appendage in Rhodocrinus pyriformis. In the Corniferous
limestone smooth round columns one inch in thickness are often
found, and these are so firmly constructed, that they must have stood
upright, supporting the body of the Crinoid, as upon the top of a
pillar. The columns are either pentagonal throughout their whole
length, or pentagonal in one part and round in another, or altogether
round and smooth. In all the species they are perforated from top
to bottom by a small central canal, which is also either circular or
pentagonal. This canal no doubt served the purpose of conveying
the nourishment from the interior of the body to every part of
the column, by which its growth was provided for. In nearly all
Crinoids the lower extremity of the column was attached to the
bottom of the sea or some other solid object, such as pieces of
floating timber, either by a number of branching rootlets, as in
Rhodocrinus pyriformis, or by a broad, solid base, as in Cletocrinus
regius. I think however that certain Lower Silurian species were
free, and moved about through the water, dragging their columns
after them. I have seen at least a hundred columns of Glyptocrinus
ramulosus with the lower part preserved, and could never discover
any signs of an attachment. In this species the column at the upper
end is often half an inch in thickness, and it tapers gradually to half

12 STRUCTURE OF THE CRINOIDEA.

a line at the lower extremity, a short piece of which, when found
perfect, is always closely curled up, like a miniature coil of rope.
I think also that sometimes the attached species had their columns
broken off by some accident, and that the animal lived long after-
wards free, but with a portion still connected with the body. I
have seen specimens of Rhodocrinus pyriformis with from six to ten
inches of the column attached to the base of the cup, with the
terminal joint where the fracture occurred rounded, and the alimen-
tary canal closed, or, as it were, healed up. There does not appear
to be any way of accounting for this condition of the column, unless
upon the above supposition.

The species of the genus Comatula now living, all of which are
true Crinoids, are attached while young, but free in the adult state.
The invaluable observations of Thompson on this genus will, as
already stated, be found at the end of this Decade. The Marsupotes
of the Chalk which have no column were also free Crinoids.

Il. Side-arms or Cirrz.

The side-arms or cirri are long, slender-jointed appendages.
attached to the column, the purpose of which does not appear to
be well understood. They have not yet been found on any of the
Lower Silurian species. Some of them are represented in the
figures given at the end of this Decade, in the article upon
Comatula.

Ill. The Basal Plates.

The base of the cup consists of a set of plates arranged in a circle
on the top of the column, and in some species where they are large
constitutes a saucer-shaped support for the viscera, to the centre of
the bottom of which support the column is attached. This part of the
skeleton has usually been called the pelvis. In nearly all the Lower
Silurian species there are five basal plates; in the Upper Silurian,
species with three or four are not uncommon ; while in the Devonian
those with five plates are comparatively rare.

IV. The Sub-radial Plates.

These are always five, and constitute a row resting upon the
upper edges of the basals. They occur in the genera Pal@ocrinus,

STRUCTURE OF THE CRINOIDEA. 13

Dendrocrinus, Porocrinus, Carabocrinus, Rhodocrinus, and others. In
Glyptocrinus, Heterocrinus, Thysanocrinus, Hybocrinus, and Cleiocrinus,
there are no sub-radials, the rays springing immediately from the
basals.

V. The Rays and Radial Plates.

In all Crinoids there are five rays, the lower plates or extremities
of which are included in the structure of the cup and form part of
the shell, while the upper portions are prolonged above the body,
and constitute the arms, which are generally free and more or less
branched. In Rhodocrinus and Glyptocrinus each ray consists at
first of a single series of three plates, sometimes called the primary
radials or simply the radials; it then divides into two series, called
the secondary radials. In these two genera the primary and secon-
dary radials enter into the composition of the cup. In Glyptocrinus
the first or lowest primary radials rest upon the upper edges of the
basal plates, alternating so that each ray is supported by the conti-
guous sides of two of the basals. In Rhodocrinus there is a series
of sub-radials between the basals and primary radials. In such
genera as Paleocrinus, Carabocrinus, Dendrocrinus, and Porocrinus, the
first primary radial only is included in the walls of the cup, but the
second plate and all above it are free. In the very remarkable
genus Cleiocrinus the primary, secondary, tertiary, quaternary and
quinary rays are all firmly connected together, the free arms com-
mencing with the sixth or seventh division.

The student will find many other modifications of the radial
system of the Crinoideze by consulting the works of various paleon-
tologists; but the above are the more common ones, and those most
prevalent in the Lower Silurian of Canada.

VI. The Inter-radials.

The divisional space between two rays is called an inter-radius ;
and as there are five rays, there must be of course an equal number
of inter-radii. Four of these are always of equal size, and are called
the ‘‘regular inter-radii,” and when they contain plates these are
designated the “regular inter-radials.” The fifth is larger than
either of the other four, and is called the ‘‘ azygos inter-radius,” from
the Greek azugos, “ unyoked,” or “not paired.” The plates in this
inter-radius are called the azygos inter-radials. In most works the
‘‘azygos inter-radials”” are termed ‘‘anal plates,” but as they are

14 STRUCTURE OF THE CRINOIDEA.

not anal plates, I think another name preferable. The azygos inter-
radials always mark the anterior side of the animal, or that side
towards which the mouth is most approximated. The posterior side
is directly opposite, and indicated by the azygos ray. There are
thus in every Crinoid two pairs of rays, the right and the left, and
an odd or azygos ray. There are also two pairs of inter-radii, the
right and left pairs, and an odd one, which is the azygos or anterior
inter-radius. When a Crinoid is placed with its anterior side
towards the observer, the left anterior ray is opposite his right
hand and the right anterior ray opposite his left. Such genera as
Glyptocrinus and Rhodocrinus have both regular and azygos inter-
radials, but Pal@ocrinus, Carabocrinus and others of a similar struc-
ture, have only the latter.

VII. The Mouth, the Ambulacral Grooves, and Ambulacral Orifices.

The space on the upper part of the body surrounded by the arms
is called the ventral surface, and, by some authors, the vault. It is
covered with plates, which are usually smaller than those of the
walls of the cup, and disposed without any observable order.
The mouth is a circular or oval aperture, situated either in the
centre of the vault or between the centre and the margin of the cup,
towards the anterior side or below the margin in the side. It
sometimes consists of a tube called the ‘“ proboscis,’ which rises
from two or three lines to more than an inch above the surface.
In some species, such as Caryocrinus ornatus (Say), it is closed by a
valvular apparatus consisting of five or six small triangular plates.
In Pentacrinus caput-Meduse there is a central orifice, and, proceed-
ing from it, five ambulacral grooves on the surface of the vault,
which radiate outwards and divide into ten before reaching the
margin. The ten grooves proceed straight to the bases of the
ten secondary rays or free arms, and are continued upon them to
their extremities. The main grooves send out branches to all the
divisions of the arms and to each of the pinnule. The grooves
throughout their whole length are covered over with a soft skin,
through which there are numerous minute circular perforations
arranged in two rows, one along each side of the groove. These
orifices are supposed to be passages for the fluid which serves to
extend or retract a set of small sucking feet which are visible on the
outside, one over each orifice. The margins of the grooves are
bordered by small erect moveable plates, which extend along the

STRUCTURE OF THE CRINOIDE. 15

sides like a fence of minute palings. These are the “marginal plates
of the ambulacral grooves.”

Figure 1.

Figure 1. Diagram of the ventral surface of Pentacrinus caput-Meduse. The
central orifice is supposed to be the mouth; the other, the anus. One of
the grooves is represented as being closed over by the marginal plates.

The grooves are covered passages, along which are conveyed from
the interior of the body to the arms and pinnule a number of
tubular vessels whose functions appear to be of great importance in
the physiology of the Crinoids. As the eggs from which the young
are produced are developed in the pinnule, no doubt there must be
an organ of some kind connected with their generation which
communicates with the viscera of the animal by passing along the
grooves. Another set of vessels are the aquiferous canals, consisting
of long, slender tubes, for the conveyance of the fluid by which the
sucking feet of the arms and pinnulz are extended or retracted.
To these must be added the blood-vessels, nervous filaments, and
muscles. Traces only of these have been actually observed, but the
almost perfect identity in structure between the ambulacra of the
Crinoids and those of the Star-fishes, in which it is well known that
such organs do exist, renders it quite certain that the former as well
as the latter are provided with a full set of ambulacral vessels.

In many of the extinct species of Crinoids, although the arms and
pinnulz are grooved, yet there are no grooves leading from the
bases of the arms to the mouth; and it therefore becomes probable
that the ambulacral vessels of the arms and pinnule do not enter
the body through that orifice. Indeed in a great many species, as
the mouth is situated in the top of a tube which is sometimes longer
than the arms and rises above them, it seems impossible that they

16 STRUCTURE OF THE CRINOIDEA.

could gain access to the interior by that route. Accordingly a more.
direct passage is provided. In a great many species which have no
calycinal grooves there is an aperture at the base of each arm in
which the groove of the arm terminates. I think that in such
species the ambulacral vessels, after descending from the extremity
of the arms to the bases of the arms, pass directly into the body
through these apertures. I have therefore, in Decade III., proposed
to call these the ‘ ambulacral orifices.”

The genera in which they are most conspicuous are Actinocrinus,
Rhodocrinus, and Platycrinus, but there is abundant evidence of their
presence in a great many other genera. The subject of these
orifices requires a good deal of investigation, as there appear to be
many important modifications upon which our Canadian specimens
throw no light. In fact all our Lower Silurian species are in such
a bad state of preservation, that many years must elapse before the
whole of their characters can be worked out. The principal varia-
tions in the position of these orifices exhibited by different of the
Crinoids, are the following :— :

1. Crinoids with the ambulacra continued from the base of the
arms over the ventral surface to the mouth—no ambulacral orifices
distinct from the mouth,—Comatula, Pentacrinus, Pal@ocrinus.

2. Crinoids with the ambulacra continued from the bases of the
arms to a single ambulacral orifice in or near the centre—the mouth
on one side—Spherocrinus, Crotalocrinus, Paleocrinus, Carabocrinus.

3. Crinoids with an ambulacral orifice at the base of each arm,
the mouth either central or between the centre and one side.

The following figures exhibit some examples of the variations
in the position of the mouth and ambulacral orifices in different
species :—

Figure 2. View of the ventral surface of Spherocrinus geometricus (Goldfuss sp.).
m, the mouth.
«3. Ventral surface of Rhodocrinus verus. m, the mouth.
“ 4, Crotalocrinus. (From Sir R. I. Murchison’s Siluria, 1st edition, p. 219.)

STRUCTURE OF THE CRINOIDEZ. 17

In S. geometricus the space on the ventral surface surrounded by
the arms is proportionally much smaller than it is in most other
species. The arms stand in a circle which is one half the diameter
of the cup. In the centre of this circular space there appears to
have been-no large plates. The arms are not placed on the edges
of the primary radials, but near the centres of the plates, which
have at the point of attachment of the arm in each a small perfo-
ration, supposed to be a passage for the brachial muscles. From
these points shallow grooves proceed to the open space in the
centre. The mouth is situated on one side, between two of th3
arms, as represented in figure 2, m.

In Rhodocrinus there are no grooves upon the ventral surface, and
the mouth is at one side, between two of the arms (see figure 3, m).
The ambulacral vessels must therefore have passed directly into
the interior through orifices at the bases of the arms.

In Crotalocrinus the mouth appears to be central, and provided
with an apparatus of small plates by which it could be opened or
closed. The ambulacral grooves radiate from it, and divide twice
or oftener before reaching the bases of the arms. There must be
therefore at least twenty arms, one for each branch of the grooves.
The grooves are, provided with marginal plates, which are repre-
sented in the figure closed down, those of one side of the groove
interlocking with those on the other side, and thus forming a roof-
like covering over the ambulacral vessels.

SECTION II.

CRINOIDEZ OF THE CHAZY LIMESTONE.

Tue lower part of the Chazy group consists of sandstones, shales,
and impure calcareous rocks, and the upper. part of limestone, in
general thick-bedded and densely crowded with organic remains.
Some of the strata of this limestone are composed almost entirely
of Rhynconella plena, others of several undescribed species of Orthis,
while many of them are little else than compact masses of the
comminuted remains of Cystideans and Crinoids..

B

18 CANADIAN FOSSILS.

There are at the present time known to be eleven species of
Crinoids in this formation, and of these five will be characterized in
the following pages; but of the other six we have as yet only the
columns and some of the detached plates. Although we cannot
determine the genera of these six species, yet it is quite certain that
they are different, not only from those hereinafter described, but
also from each other. None of the species are clearly identical
with any that occur in either the Black River or the Trenton
limestones, although one, Hybocrinus pristinus, is closely allied to
H. tumidus, and may perhaps be a variety thereof.

The Crinoids and Cystideans of the Chazy appear to have been
confined to a comparatively small area of the Silurian ocean. The
grey limestone in which they occur is exposed in numerous localities
on the islands of Montreal, Jesus, and Bizard, and in that tract of
Silurian country which lies between the Ottawa and St. Lawrence
rivers. It also extends from the island of Montreal southerly to the
neighbourhood of Lake Champlain, and is largely exposed at the
village of Chazy, the typical locality of the formation. This part
of the formation has not been identified west of Kingston, nor so far
east as Three Rivers. It lies therefore altogether within an area
of about two hundred miles in length by one hundred in breadth.
Outside of this area none of the Chazy Crinoids or Cystideans have
been discovered.

Although for practical purposes it is most useful to treat of the
Chazy as a formation distinct from that of the Birdseye and Black
River limestone, yet the two deposits are most closely connected
zoologically, since we find that, out of seventy-five species, about
twenty, or more than one fourth, are common to both.

BLASTOIDOCRINUS CARCHARIZDENS, Billings.

Plate I. Figures 1a, 12.

Description —Although the remains of the somewhat extraordinary
species for which the above name is proposed are exceedingly
abundant in the Chazy Limestone, and have for a long time attracted
the attention of geologists, yet no specimens have been collected
sufficiently perfect to enable us to make out the arrangement of all
the parts. Indeed, so remarkable is the form of the principal plates,
and so unlike any other fossils known in the Lower Silurian rocks,
that, until very recently, no one has succeeded in shewing how they

CANADIAN FOSSILS. 19

could be brought together at all in such a manner as to constitute
an organic structure. By several fortunate discoveries, however, of
fragments of the body, with some of the plates still occupying their
natural position, we are now in possession of data by which the
more important details can be demonstrated, and no doubt other
specimens will in course of time be found to supply the remainder.

The remains of this species most usually occur in an extremely
comminuted state, and in such abundance that in many localities
they constitute almost the whole of the ingredients of beds of solid
rocks, of from six inches to three feet in thickness. Very frequently,
where the rock has been long exposed to the action of the atmos-
phere, the large unbroken plates are weathered out and displayed in

strong relief upon the surfaces of the strata; and as they are easily

recognized and strictly characteristic of the Chazy limestone, they
constitute-a most valuable and safe guide to the explorer in tracing
out the distribution of the formation, or in determining the age of
isolated patches where other fossils may be absent, or where the test
of superposition cannot be made available.

The form of these large plates is nearly triangular, two of the
sides being straight or gently curved outwards, and the third more
or less strongly arched inwards. This last mentioned side, when‘the
plate is in its natural position in the perfect cup, is the lower side,
and the angle immediately opposite to it the apex. The plates are
not flat, but have a concavity extending from the apex downwards,
being the deepest at the base, thus giving a form somewhat like that
of an ordinary shoe-lifter. The length of the base measured in a
straight line between the two lower angles, and, without following
the curvature, is, in a specimen of the average size, about ten lines;
the length of the other two sides, when compared with the base, is
either equal to it or a little greater. The surface is ornamented with
fine straight parallel striae, from six to ten in the width of a line, and
running in a direction from the base upwards. When the specimens
are a little worn these striz are obliterated, and the surface is then
smooth or granular. The concave side of the plate is the outer side.

The specimen represented by figures 1z, 1% and 1/, Plate I., shews
that the upper or ventral surface of the perfect fossil is divided into
five equal portions by five rays or pseudambulacra, which radiate
from the centre outwards, and that the place of the triangular plates
above described is in the angles between the rays. There are thus
five of these plates in the skeleton of each individual. The rays
consist of two rows of narrow, elongated plates, placed transversely,

20 CANADIAN FOSSILS.

and which appear to be the homologues of the ambulacral plates of
the rays in the genus Pentremites. The width of the rays near the
centre is two lines, and there are four of the small transverse or
ambulacral ossicula in the length of one line. The specimen does
not shew the centre of the ventral surface, so that we cannot deter-
mine whether the mouth was situated there or not. In order to
exhibit the analogy or affinity between this genus and Pentremites, I
have had the following figures prepared :—

TOWNES AN
Lo
© ei \
ZL)

ats

Set
RSC

Fig. 5. Fig. 6.

Figure 5. The ventral surface of Pentremites pyriformis (Say). d, the deltoid
plates, extending only half the length of the pseudambulacra.

“6. The ventral surface of Blastoidocrinus carcharieadens. d, the deltoid

plates, extending the whole length of the pseudambulacra. The

unshaded space in the centre is most probably the place of the

mouth.

Fig. 7. Fig. 8.

Figure 7. Side view of P. pyriformis.
“ 8. The same, but with the deltoid plates extended to the extremities of

the pseudambulacra, as in B. carchariedens.

From the above figures it appears quite probable that the large
trianguiar plates of this species are the exact homologues of the
deltoid plates of the Pentremites. If we imagine a pentremite with
jts deltoids so greatly developed that they would occupy the whole

CANADIAN FOSSILS. ' 21

of the spaces between the pseudambulacra, the structure would be
exactly that of the upper surface of Blastozdocrinus.

From another specimen it appears that there are at least three,
if not four or five, basal plates, and their form is remarkable, as
they do not rest upon the upper surface of the upper joint of the
column, as in the ordinary Crinoids, but have their inner edges
turned upwards into the body of the cup, leaving a circular aperture
in the bottom through which the column actually penetrates into
the interior, nearly if not quite to the top of the visceral cavity.
This is so extraordinary a structure that scarcely any. paleontologist
at all well acquainted with the organization of the Crinoidez could
be brought to believe it without personal inspection of the proofs.
The two specimens in which the evidence is exhibited were
discovered in two different localities. That represented by figures
12, 1k and 11, I found in a wall about half a mile west of the village
of St. Laurent, on the island of Montreal; the other, figure 1m, in
a quarry five or six miles east of the village. It is quite clear that
they are not portions of the same individual. The St. Laurent
specimen is part of an individual split in two from top to bottom,
and exposing the interior exactly where the column should be found,
if it penetrate through the base to the upper part of the visceral
cavity, as above supposed. Such is its position in the specimen, as
shewn in figure 1/. I at first thought that this might be the result
of some accident; but having soon afterwards found the specimen
represented by figures 1m and 1n, where a piece of the column is seen
penetrating through the base, I believe it to be the natural arrange-
ment. The column is round, with an alimentary canal so small that
often the detached joints seem to have no central perforation. I
have seen it however distinctly in a great many specimens. The
flat faces of the separate joints exhibit strong radiating striz.
Thickness of column, two lines; and of the joints, from one fourth
to half a line.

We often find associated with the remains of B. carchariedens some
small fossils which appear to be the joints of a pentagonal crinoidal
column. I have represented several of these by figures lo, 1p, 1s,
plate 1. They have five concave sides, and usually one end is
rounded (see figure 1s), and the other generally flat, with five deep
grooves radiating from the centre to the angles. In some specimens
both ends are rounded ; in many there is no central perforation, but
in others there is. These are certainly crinoidal remains, but we
shave no means of shewing to what species or genus they belong.

22 CANADIAN FOSSILS.

EXPLANATION OF Figures. Puatse I.

Figures la—1h. Deltoid plates of B. carchariedens.
a. li. Side view of a specimen which has three of the rays partly preserved.
os 1k. The same, seen from above.
s ll. Verticai section, shewing the position of the column in the interior.
ke lm. Fragment of the base, shewing the manner in which the column
penetrates into the visceral cavity.
1n. Under side of 1m.
6 lo-ls. Small pentagonal crinoidal remains found associated with B.
carchariedens.
Locality and formation.— Caughnawaga, Island of Montreal, Isle

Jesus, Isle Bizard. Chazy limestone.

PACHYOCRINUS CRASSIBASALIS, Billings.
Plate I. Figures 3a, 30.

Description.—Of the species for which the above name is proposed
no perfect specimen has been found, and yet we have sufficient to
shew that it belongs to a new genus. There are five small penta-
gonal basal plates concealed within the cavity for the attachment
of the column. Above these and alternating with them are five
very large and thick plates, which may be either sub-radials or
first-radials. The lower portions of these plates are curved under
the body, so as to constitute a broad, rounded or concave bottom to
the cup, which has a width of nine lines at a height of about two
lines. At this level the cup is broken off in the only specimen
discovered, and we have no means of determining what was the
structure above. There are no other Crinoids in the Lower Silurian
rocks with a base like this, for although in the genus Rhodocrinus
some of the species have a concave bottom, yet the sub-radial plates
are always small and thin. It is true that mere difference in the size
of organs or portions of an organic structure is not always of generic
value; yet, where it is so extremely great as it is between the
sub-radials of Rhodocrinus and the second series of this species, it is
generally found that other differences exist sufficient to warrant a
separation of the species in which such differences occur into distinct
genera. I am inclined to believe, therefore, that when perfect spe-
cimens are found they will shew that this is a new genus.

EXPLANATION OF Figures. Puars I.
Figure 3a. View of the base of the specimen.
« 3b. Side view of the same.

Locality and formation—Two miles north of Montreal, in the

Chazy limestone.

CANADIAN FUSSILS. 23

Genus Hysocrinvs, Billings.

(Hysocrinus, Report Geological Survey of Canada, 1856, page 274.)

ForRMULA :

Basal plates, 5. | Azygos inter-radials, 2
Radial plates, 15. Regular inter-radials, 0

Figure 9.

Figure 9. Diagram of the structure of the cup of the genus Hybocrinus.

Generic characters—Cup, globular or pyriform, more protuberant
upon one side than on the other, composed of five basal, five radial,
and two azygos plates. The five basal plates are pentagonal, and
alternating above them is a row consisting of one large azygos plate
and four of the radials. The large azygos plate supports upon its
upper right-hand sloping edge the second small azygos, and on the
left the fifth radial. - The arms in all the species that have yet been
discovered are undivided, and each is composed of a single series of
joints. The column is round and short. The generic name is
derived from the Greek hubos (bent outwards or hump-backed).

HYBOCRINUS PRISTINUS, Billings.

Plate I. Figure 2a.

Description.—This little species is usually about three lines in
height and four lines in width, measured across the cup from the
posterior to the anterior side. The anterior side is very protuberant,
and the plates, although they appear smooth to the naked eye, yet,
when a little magnified, are seen to be covered with small irregular
tubercles. The arms are single and somewhat narrowly rounded on
the back, the joints about one line in length. The column is round,
half a line in thickness, and composed of joints which are, as far as

Nore.—In. the expression radial plates, 1X5, the figure 1 indicates the number of
plates in each primary ray, and the figure 5 the number of rays. In the diagram the
shaded plates are the azygos inter-radials.

24 CANADIAN FOSSILS.

known, of an uniform size, there being on an average about ten in
the length of two lines. '

This species so closely resembles H. tumidus of the Trenton lime-
stone, that I have had much doubt as to the propriety of separating
it therefrom. The only differences that I can perceive are, that it is
always smaller than the Trenton form, the plates more coarsely
granulated under the lens, and not so convex in their centres.
The column does not taper so rapidly, and it is composed of joints
which are thicker in proportion. In a well-preserved specimen of
H. tumidus the column exhibits from eight to ten joints in the length
of one line, whereas in H. pristenus there are only five. Under these
circumstances I have thought it best to distinguish the Chazy speci-
mens by a separate name for the present.

Locality ond formation.—Detached plates are rather common in the
Chazy limestone at Caughnawaga, and at various localities on the
Islands of Montreal, Jesus and Bizard; also in the front part of the
Township of Hawkesbury. Perfect specimens are rare.

Genus PALZOCRINUS, Billings.

ForMuLA :
Basal plates, 5. Azygos inter-radials, 1-3.
Sub-radial plates, 5. Regular inter-radials, 0.
Radial plates, 1x5. Calycinal ambulacra, 5.
Figure 10.

Figure 10. Diagram of the cup of the genus Paleocrinus. The azygos inter-radial
space is left blank in the figure, as it is not certain how many plates it contains.

Generic characters—Cup, oval or pyriform, composed of five pen-
tagonal basal plates, alternating above which are four hexagonal and
one heptagonal sub-radial plates, and above these five radials bearing
the free arms. The heptagonal sub-radial supports upon its trun-
cated summit one, two, or three small azygos inter-radials. The rays
are slender, and free from the second joint inclusive. There are five
calycinal ambulacral grooves radiating from the centre of the abdo-
minal surface to the bases of the arms, where there appear to be

CANADIAN FOSSILS. 25

also five small orifices leading to the interior. The mouth is pro-
bably situated near the margin, at the azygos inter-radius. Column,
either round or pentagonal.

This genus belongs to that group of the Crinoidez which includes
such genera as Cyathocrinus, Poteriocrinus, Dendrocrinus and Porocrinus,
to all of which it is closely allied in structure, but differs in the
presence of calycinal ambulacral furrows.

PALMOCRINUS STRIATUS, Billings.
Plate I. Figures da, 5d.

Description. —Cup, oval, gradually expanding from a small base to
the width of five lines at the margia of a specimen seven lines high.
The plates are depressed convex, and have a small round tubercle in
the centre. They are also beautifully ornamented with radiating
strize or somewhat sharp,’elevated ridges. One of these extends from
the centre of each plate to the middle of each edge, and, crossing the
suture at right angles, proceeds straight to the centre of the conti-
guous plate. Parallel with these principal ridges are four or five
other shorter ones, also crossing the suture at right angles. Those
nearest the principal ridge are the longest, and the length gradually
decreases towards the angles. Where the ridges cross the suture,
there are from three to five of them in the width of one line.

The only specimen collected shews very distinctly two ambulacral
orifices at the bases of two of the arms, and two calycinal ambulacra
leading therefrom towards the centre. The other three grooves are
indistinctly indicated, but sufficient appears to leave little doubt as
to their existence. The arms and column are unknown.

The plates of this species so closely resemble those of the cysti-
dean Palaocystites tenuistriatus, that they can only be distinguished
after much practice. The striz on the surface of the latter species
are always a little finer and of a nearly uniform size.

EXPLANATION OF Figures. Puate I.

Figure 5a. Posterior side of a nearly perfect specimen.
«5b. Summit of the same, shewing the ambulacral orifices and grooves.

Locality and formation.—Somewhat common in the Chazy limestone
at Caughnawaga and on the Island of Montreal.

26 CANADIAN FOSSILS.

Genus Ruopocrinus, Miller.

(Ruopocrinvs, Miller, 1821. Natural History of the Crinoidee, page 106.)
(GitBERTsocrinvs, Phillips, 1836. Geology of Yorkshire, vol. ii., page 207.)
(Taysanocrinvs, Hall, 1852. Paleontology of New York, vol. ii., p. 186.)

FoRMULA :
Basal plates, 5.
Sub-radial plates, 5.
Radial plates, 3x5.

Regular inter-radials, 6 to 8X4.
Azygos inter-radials, 7 to 12.

Figure 11.

Figure 11. Diagram of the structure of the cup in the genus Rhodocrinus.

Generic characters.—Cup, globular or oval; arms, long, often much
branched, and densely fringed with pinnule; basal plates, five,
alternating above which are five sub-radials; primary rays, five,
consisting of three plates each ; secondary rays, ten, the number of
plates in each varying from one to four. The number of regular
inter-radials varies from six to eight, while the azygos inter-radials
are more numerous. The free arms spring from the secondary
radials. In all the Canadian species the column is round, strongly
annulated in the upper portion, and smooth below. The radix or
base of attachment consists of a number of small, branching roots.
The ambulacral orifices are situated at the bases of the arms, and
the mouth, in all the species in which it has been observed. i»
excentric.

CANADIAN FOSSILS, aT

In the “Natural History of the Crinoidew” Miller described this
genus as having only three basal plates, an error into which it was
easy for him to fall, on account of the minuteness of these plates in
most of the species. In consequence of this mistake, several other
genera were founded on specimens with five basal plates; but as it
has been ascertained that Miller’s original specimens have also five,
these genera cannot be retained.

In the Report of the Geological Survey of Canada I referred with
doubt two of our species, f. pyriformis and R. microbasalis, to the
genus Thysanocrinus of Hall. They are very clearly congeneric
with the Thysanocrinus liliformis of the Niagara limestone, while
they have also in general the same structure as Rhodocrinus. There
are however some differences in the form of the body and the upper
parts which led me to think the genera might be distinct; but not
being decided, I referred them to Thysanocrinus, at the same time
giving the other name in a parenthesis. During the last summer I
discovered the small species, R. asperatus, which has not only the
structure but the aspect also of the typical forms of Rhodocrinus,
and I think therefore that our three species should be placed in that
genus.

RHODOCRINUS ASPERATUS, Billings.
Plate I. Figures 4a—4e.

Description—Cup, small, nearly globular; surface covered with
numerous small, conical, irregular tubercles. The basal plates are
so exceedingly diminutive as to be entirely concealed within the
cavity in the centre of the base in which the column is inserted.
The column is round, and strongly and closely annulated near the
base with very thin, sharp, projecting joints or rings, as in the other
species of this genus. Judging from some fragments found associated
with the specimen figured, it would appear that the arms are long
and thickly fringed with well-developed pinnule. Height of cup in
the only specimen discovered, six lines; diameter, the same.

EXpLANATION OF Figures. Puate# I.

Figure 4a. Side view of the specimen.

«4b. View of the base.

“ 4c. A radix found in the same slab along with 4a.

“ 4d. Portion of the surface of 4c magnified. The joints of this column
appear to be composed near the root of five pieces each, which
interlock, as represented in the figure 4d. ’

“ 4e, Transverse section of the column near the root.

28 CANADIAN FOSSILS.

Locality and formation—This species occurs in the Chazy lime-
stone, in a quarry about two miles north of the City of Montreal.
Exceedingly rare.

SECTION III.

CRINOIDEZ OF THE TRENTON LIMESTONE AND HUDSON RIVER GROUP.

ALTHOUGH in almost every exposure of the Trenton limestone we
find remains of the Crinoidez, yet in general they consist of mere
fragments, such as joints of the column or the detached plates of
the cup. At the city of Ottawa they are found in a better state
of preservation, but seldom perfect. Nearly all the species that
we have been able to determine were collected at that locality;
and as we know, from the researches of geologists in other countries,
that these fossils are often confined to limited areas, it appears
probable that few of ours will be found elsewhere.

The Hudson River species are so closely allied to the Trenton
that I have not thought it necessary to describe them in a separate
section.

Hysocrinus Tumipvs, Billings.

Plate II. Figures 1a—le.
(H. rumpus, Report Geological Survey of Canada, 1856, page 275.)

Description —Smaller than H. conicus; sub-globular, the plates
tumid in their centres; column, slender and round, composed of
thin joints, and tapering towards the base; surface of the plates,
obscurely granular; length of cup, six lines; breadth at margin,
about eight lines; arms, one line broad upon the back, composed of
joints one line in length. Although about twenty heads of this
species have been collected, none of them are quite perfect.
They all are smaller and of a different form from H. conicus.

CANADIAN FOSSILS. 29

The ambulacral orifices in this species are indicated by a strong,
narrow, rounded channel in the centre of the upper edges of the
primary radial plates.

EXPLANATION OF Figures. Puats II.

Figure 4a. View of the anterior side of a specimen, shewing the azygos plates.
“ 1b-ld. Different views of other specimens.
‘© Je. A polished transverse section just below the base of the arms, shewing
the channels in the primary radial plates for the ambulacral
orifices.

Locality and formation —Trenton limestone ; City of Ottawa.

Hyzocrinus conicus, Billings.

Plate II. Figures 2a—2b.

(H. conicus, Report Geological Survey of Canada, 1856, page 274.)

Description.—In this species the cup is conical, with slightly
ventricose sides ; the base narrow, and the arms long and undivided ;
plates, smooth; height of cup, thirteen lines from the base on the
azygos side to the upper margin; height of the opposite side, nine
lines; length of the arms, three inches; the basal plates occupy
more than one half the height on the azygos side and about one half
on the others; the arms are one line and a half in width, broadly
rounded on the back, and composed of a single series of joints,
each one line in length; on their insides the ambulacral grooves are
margined by rows of small plates resembling those upon the arms
of some of the Cystideze (Plewrocystites) ; about five of those plates to
one joint of the arm. The column is round and smooth, consisting
of very thin joints, ten to one line. The mode of attachment to the
bottom was by a broad button-shaped base. Length of column in
the largest specimen seen, one and three-quarter inches.

EXPLANATION OF Figures. Puate II.

Figure 2a. Right side of a specimen of the average size.
“2b. Left side of another specimen.

Locality and formation.—Trenton limestone, City of Ottawa.

30 CANADIAN FOSSILS.

Genus CARABOCRINUS, Billings.

(Carazocrinus, Report Geological Survey of Canada, 1856, page 275.)

ForRMULA:

Regular inter-radials, 0.
Azygos inter-radials, 3.

Basal plates, 5.
Sub-radial plates, 5.
Radial plates, 1X5.

Figure 12. Diagram of the structure of the cup in the genus Carabocrinus.

Generic characters.—Cup, globular or ovoid; basal plates, five, four
of them pentagonal, and the fifth hexagonal; sub-radials, five, three
of them hexagonal, one heptagonal, and one pentagonal, the latter
smaller than the others; primary radials, five, each bearing an arm
which is several times divided. The azygos inter-radius is rather
large, and occupied by three plates. One of them is supported upon
the hexagonal basal plate; a second upon the small pentagonal
sub-radial ; the third is situated between the two anterior primary
radials, its upper edge forming the margin of the cup, and its two
lower sides resting upon two of the upper sloping sides of the first
and second azygos plates.

Upon the ventral surface five calycinal ambulacral grooves radiate
from the centre (where there appears to be an aperture) to the bases
of the arms; the mouth is situated in the margin over the azygos
plates; there is a small aperture, surrounded by an elevated border,
half-way between the mouth and the centre. *I think this small
orifice is the anal aperture.

This genus is distinguished from the genera Cyathocrinus and
Poteriocrinus by the depth to which the azygos inter-radials descend.
In these two genera they are always situated above the sub-radials ;
but in Carabocrinus one of them stands upon one of the basal plates.
The generic name is from the Greek karabos, a crab.

CANADIAN FOSSILS. 31

CARABOCRINUS RADIATUS, Billings.

Plate II. Figures 3a—3e.
(C. napiatus, Report Geological Survey of Canada, 1856, page 276.)

Description Cup, globose, rather broader at the margin than it is
high; base, broadly rounded; surface, covered with strong rounded
ridges, which radiate from the centres of the plates; arms, short,
three times divided; column, round and slender, composed of alter-
nately projecting thin joints. From the centre of each sub-radial
plate two principal ridges ascend diagonally to the bases of the two
arms on both sides; two others radiate to the centres of the two
sub-radials on either side; and thus a series of triangles is formed
round the upper half of the cup. Ina similar manner ridges extend
from the centres of the sub-radials to the centres of the basal plates,
thus constituting another set of triangles in the lower half. Within
each triangle, both in the upper and lower halves, are contained two
or three smaller triangles, one within the other. In consequence of
this arrangement, the ridges appear to radiate in groups of three or
four.

Each arm-plate supports in its centre a small but stout pentagonal
second radial plate, from the upper sloping edges of which spring
two short round arms, which divide again at the second joint ; these
branches are again divided once or twice above. Height of the
largest specimen, one inch; diameter at half the height, fourteen
lines. Specimens are in the collection of all sizes, from three lines
to twelve in diameter.

EXPLANATION OF Figures. Puatr II.

Figure 3a. View of the anterior side, shewing the azygos inter-radius.

«3b. Base of the same specimen.

“« 3c. Posterior side of a different specimen.

“3d. Ventral surface of a small individual. In the centre of the lower side
of the figure is the mouth, and directly above it the small anal
aperture.

“* 3e, Ventral surface of a larger specimen, shewing obscurely the five
ambulacral grooves. The three round darkly-shaded spots appear
to be apertures accidentally produced.

For the fine specimen represented by figures 3a and 30, we are
indebted to Mr. Charles Wright, of Hull, Ottawa.

Locality and formation.—Trenton limestone; City of Ottawa.

32 CANADIAN FOSSILS.

CARABOCRINUS VANCORTLANDTI, Billings.

Plate II. Figure 4.

Description —Of this fine and rare species only one specimen has
been seen, and that is unfortunately so much injured on the anterior
side that the arrangement of the azygos plates cannot be determined.
The form of the body is rather broad oval, the height being fifteen
lines from the base to the margin, while the greatest diameter near
the centre of the body is twelve lines. The base is narrowly
rounded, and the cup expands gradually for about half the height,
above which it contracts to the margin, where the width is about
one line less than it is at the centre. The height of the posterior
basal plate is five lines and a half, its greatest width four lines; the
hexagonal basal, five lines high and about the same in width. Of
the sub-radials, three are well-preserved ; they are slightly narrower
below than above. Height of the sub-radiais, eight lines; width
between the two upper lateral angles, seven: lines, and between the
two lower, five lines. The primary radials are each six and a half
lines wide and five lines high. The arms are rounded on the back,
and a little more than one line in thickness. They have each three
single joints, the third being pentagonal and supporting upon its
upper sloping sides two secondary rays, which are subdivided at
the distance of two lines and a half.

The surface is ornamented with radiating ridges, as in C. radvatus ;
but the ridges are proportionally smaller and more distant from
each other.

This species is clearly distinct from C. radiatus, from which it
differs in being of an oval instead of a subglobular shape. In all the
specimens of C. radiatus the width is greater than the height; while
in C. Vancortlandti the height is greater than the width. It is also
to be observed, that in the former the arms divide above the second
free joint, and in the latter above the third.

The species is dedicated to Dr. E. Vancortlandt, of the City of
Ottawa, whose zeal in the advancement of science has been produc-
tive of many beneficial results. The only specimen known belongs
to his cabinet, and has been kindly communicated by him to us for

description.
EXPLANATION OF Figures. Puate II.

Figure 4 exhibits a view of the posterior side of the specimen.

Locality and formation —Trenton limestone ; Township of McNab,
near Arnprior.

CANADIAN FOSSILS. 33
CARABOCRINUS? TUBERCULATUS, Billings.
Plate X. Figures 2a, 20, 2c.

Description.—Cup, sub-globular or broadly oval; surface of plates
covered with small, rounded tubercles; arms, large, long, several
times divided; column, round, and in the upper part composed of
alternately thick and thin joints.

Of this species we have only one specimen, and that is imperfect.
The distinctive characters are the tuberculated surface and large
arms. Although I have not seen the azygos inter-radials, yet the
general aspect of the specimen is so much like that of Carabocrinus,
that I have little doubt it belongs to that genus.

ExpPLANATION OF Figures. Prater X,

Figure 2a. The only specimen collected.
« 2b. Three joints of the column, enlarged.
“2c. One of the joints of the arms, enlarged.
Locality and formation.—Hudson River group, Charleton Point,
Anticosti.

Genus Porocrinus, Billings.

(Porocrinus, Report Geological Survey of Canada, 1856, page 279.)

FORMULA :
Basal plates, 5. Regular inter-radials, 0.
Sub-radials, 5. Azygos inter-radials, 2.
Radials, 1 x 5.

‘Figure 13. Diagram of the structure of the cup in the genus .Porocrinus.
Generic characters.—Cup, conical; basal plates, five, pentagonal ;
sub-radials, five, three hexagonal and two heptagonal; primary
radials, five ; one large azygos inter-radial, supported on the trun-
cated summit of the anterior sub-radial, and one small one, situated
Cc

34 CANADIAN FOSSILS.

over the suture between the anterior and left anterior sub-radials,
and having above it on one side the large azygos, and on the other
the left anterior primary radial; several small pectinated rhombs,
similar to those of the Cystidez.

The characters of this genus are nearly the same as those of
Cyathocrinus, Poteriocrinus ete., but differs from these and other allied
genera in the presence of the pectinated rhombs. Only one species
is known.

POROCRINUS Conicus, Billings.

Plate II. Figure 5a-5d.

(P. conicus, Report Geological Survey of Canada, 1856, page 279.)

Description.—Cup, one line and a half in diameter at the base. and
gradually enlarging, with slightly ventricose sides, to the width of
five lines at the margin; height, seven lines; basal plates narrow,
nearly two lines high ; sub-radials, three lines in height ; first primary
radials, about two lines and a half in height and breadth; all the
plates smooth ; column, circular, smooth, and suddenly enlarged near
and up to the base of cup, composed of very thin joints; free rays,
long, slender and single to their extremities ; they are about half a
line in thickness, and appear to be composed of a single series of
joints. Only about one inch in length of the column next the base
has been seen.

In this species there exists a number of poriferous areas resembling
the pectinated rhombs of the Cystideze in their structure, and probably
adapted to the performance of the same functions. Their forms and
position are however somewhat different from those of any known
cystidean. In fossils of the latter order these organs consist of two
parts, one situated upon each of two contiguous plates, but in this
crinoid, each is so placed that it occupies the angles of three plates.
Their form is that of an equilateral spherical triangle, and their size
about one line in diameter. There are five situated at the apices of
the five basal plates, five at the lower angles of the arm-plates, five
at the apices of the sub-radials and five between the arm-plates on
the margin of the cup. There are also two or three small ones at
the angles of the azygos-plates, in all twenty-two or twenty-three.
The pores consist of fine elongated parallel slits, which appear to
penetrate through the plates; they are not at right angles to the
margin of the plates as in the Cystidez, but oblique.

CANADIAN FOSSILS. 35

The central pore of each division divides the angle into two equal
portions, and all the other pores upon the plate are parallel to this
central one ; consequently in each area they have three directions in
which they are at right angles to the sides of the triangular space in
which they are situated, but oblique with respect to the margins
of the plates.

EXPLANATION OF Figures. Puate II.

Figures 5a, 5b. Posterior views of two specimens.
“* 5e. Anterior side of a specimen, enlarged to shew the azygos plates and
poriferous areas.
“5d. ©=Ventral surface of 5a.

Locality and _formation.—Trenton limestone, City of Ottawa.

Genus DENDROCRINUS, Hall.
(Denprocrinus, Hall, Paleontology of New York, volume ii., page 193.)

ForRMULA:

Regular inter-radials, 0.
Azygos inter-radials, 1.

Basal plates, 5.
Sub-radials, 5.
Radials, 1X4-+ 1X2 =6.

Figure 14. Diagram of the structure of the cup in the genus Dendrocrinus.

Generic characters—In this genus there are five pentagonal basal
plates, and alternating above these a series of five sub-radials, one of
which has its superior angle truncated, and supports a large azygos
inter-radial. There are five rays alternating above the sub-radials ;
the ray on the left-hand side of the large azygos inter-radial has two
of its plates entering into the composition of the cup ; this ray is free,
from the third joint inclusive; of the other four rays, only the first
" joint is included in the cup. A large and long proboscis rises from
the azygos inter-radial plate.

36 CANADIAN FOSSILS.

This genus is exactly the same in the composition of the test as —
Cyathocrinus with the exception of the peculiarity that one of the
rays has two of its joints contained in the walls of the cup. In the
original description given by Professor Hall, (Pal. N. Y., vol. 2,
p- 193,) four series of plates are mentioned, including five ‘ scarcely
visible” plates beneath those which I regard as constituting the true
base ; they cannot be seen in any of the specimens in the collection
of the Survey, although at least four of the species are unquestionable
congeneric with D. longidactylus (Hall).

I have seen Professor Hall’s specimens, and he agrees with me
that the generic description may be so modified as to receive many
species with the same structure in other respects, but which do not
exhibit the small plates at the base. It will be seen by referring to
fig. 7, c, plate 42, vol. 2 Pal. of New York, that the column of D.
longidactylus consists of alternately large and small (or thin) joints,
and that the latter sometimes consist of five divisions. Professor
Hall is now of opinion that the small pieces at first regarded as
constituting the true base are not of generic importance, and that
they may be considered either as one of the quinquepartate thin
plates of the column, or as a basal series so little developed as not to
be of more than specific value.

It will be recollected by those who have studied the Crinoidee,
that a similar question relating to the base of Poteriocrinus still
remains unsettled ; Professor Philips and the Messrs. Austin having
published that genus with three minute plates situated under the
three basal plates.

DENDROCRINUS GREGARIUS, Billings.

Plate III. Figures 1a, 18, 1c.
(D. errgarius, Report Geological Survey of Canada, 1856, page 265.)

Description.—Cup, acutely conical, from three to eight lines in
length, and from two to six lines broad at the greatest diameter,
which is at the margin, whence to the small pointed base it tapers
uniformly with nearly straight sides; basal plates, narrow, nearly
one third the height of the cup ; sub-radials, rather more than one
third broader than high ; large azygos inter-radial, not quite so large
as the plate on which it stands, broader above than below ; proboscis,

CANADIAN FOSSILS: 37

for several lines. above the azygos, nearly as wide as the cup, and
composed of numerous small plates, which appear to be regularly
arranged in upright rows; the arms bifurcate once immediatly after
becoming free, and many times again above ; they are very long and
obtusely angular on the back. Below the first bifurcation there are
about four joints, and they occupy a length of two lines im a speci-
men where the cup is six. lines high and the arms two inches and
one-fourth long. Their thickness in this part is about half the width
of the first primary radial plates from which they spring, and they
appear to hold a very deep groove on their inside, as the thickness is
greater in that direction than it is in the other ; the column is round,
slender and flexible, slightly enlarging near and up to the base of the
cup, and composed of alternately thick and thin joints, about six of
each in a line of the length; the plates are without ornament.

This species so much resembles D. longidactylus (Hall) of the
Niagara group that it can scarcely be separated. The principal
differences consist in its smaller dimensions, and in the absence of
the vertical ridges along the proboscis. On comparing with the
illustrations given in the Palzontology of New York, it will be seen
that the second plates of the rays on each side of the proboscis are
in fig. 1a, plate 43, broader than those upon which they rest. In
our specimens the second plate of the left-hand ray is equal to the
first ; in the right-hand ray it is a great deal less, agreeing in this
respect with fig. 7a, plate 42. The species are closely related, and
yet I am satisfied they are different.

EXPLANATION OF FicurEs. Puats III.

Figure la. Posterior view of a specimen.
cS 1s. "The! lett side:
“ Te. Column, enlarged.

Locality and formation.—City of Ottawa, in the central part of the
Trenton limestone.

DENDROCRINUS ACUTIDACTYLUS, Billings.
Plate III. Figures 2a, 20.
(Report Geologicul Survey of Canada, 1856, page 266.)

Description—Cup, small, conical somewhat pentagonal ; arms,
very slender, several times sub-divided and excessively sharp on the
back; column, round, composed of small nearly globular joints ;

38 CANADIAN FOSSILS.

length of cup in the specimen examined, two lines, breadth at base of
free rays, the same; length of free rays, one inch and one-eighth ;
thickness upon the back below the first sub-division, about one-fifth
of a line. At three-fourths of an inch below the base of the cup
there are five joints of the column to one line in length. The two
arms visible in the specimens bifurcate at the fourth free joint, and
three times again at varying distances above. Only one side of the
specimen can be seen, yet the characters of the cup and arms are so
similar to those of the last species that there can be little doubt of its
generic affinities while the globular joints of the column and the thin
sharp backed arms are characters sufficient to separate them speci-
fically.

EXPLANATION OF Figures. Puarte III.

Figure 2a. Posterior side of a specimen,
‘2b. + Portion of the column, enlarged.

Locality and formation.—Upper part of the Trenton limestone, near
the Toll-gate, St. Lawrence Street, Montreal.

DENDROCRINUS PROBOSCIDIATUS, Billings.

Plate III. Figures 3a, 38, 3c.
(D. proposcipiaTus, Report Geological Survey of Canada, 1856, page 267.)

Description.— Cup, small, conical sub-pentagonal ; proboscis,
enormously large in proportion to the size of the cup; column,
pentagonal with raised edges along the five angles, and with concave
faces between, composed of very thin joints, twenty-four in the
length of two lines; the arms are thin and sharp on the back. Ina
specimen, the crushed cup of which is three lines in length, there is
a proboscis attached, sixteen lines in length; the portion seen is of a
very remarkable structure; it is composed of four vertical rows of
small plates, with a strong central keel running up each row, from
either side of which projects, nearly at right angles, a pair of short
ridges to the outer side of each plate, giving to the surface the
appearance of several small rope ladders side by side, as in the
rigging of a ship. This peculiar style of ornament is well shewn
in the figures of D. longidactylus (Hall), Pal. N. Y., vol. 2, fig. 7a,
plate 42, but the pattern is somewhat different; in that species the
transverse ridges diverge from each other at an angle of about 45

CANADIAN FOSSILS. 39

degrees, but in this the divergence is only about 20 degrees, pro-
ducing to the eye a very different effect.

EXPLANATION OF Figures. Puare III.

Figure 3a.- Anterior side.
“3b. Part of surface of proboscis, enlarged.
«3c. Portion of column, enlarged.

Locality and _formation.—Upper part of the Trenton limestone, near
the Toll-gate, St. Lawrence Street, Montreal.

DENDROCRINUS HUMILIS, Billings.

Plate III. Figure 4.
(D. numitis, Report Geological Survey of Canada, 1856, p. 270.)

Description.—Cup small, conical ; arms, nearly as broad as the first
primary radials, divided at the fourth or fifth joints, and again above:
the basal plates are small, their height about equal to their width,
the sub-radials three times larger than the basal plates; the first
primary radials are low and broad ; column, unknown ; height of cup,
two and a half lines, breadth at the margin, the same.

EXPLANATION OF Figures. Puate III,

Figure 4. Posterior view of the only specimen discovered.

Locality and formation.—Trenton limestone, City of Ottawa.

DENDROCRINUS LATIBRACHIATUS, Billings.

Plate III. Figures 5a, 5), 5c.
(D. uatipracniatus, Report Geological Survey of Canada, 1856, page 270.)

Description.—This species is most closely related to D. humilis, the
only difference being in the greater breadth and length of the arms,
which at the base are quite as wide as the first primary radials, and
become a little broader above, whereas in the other species they
become narrower from the base upwards. The bottom of the cup is
more rounded than in D. humilis, and as the columns of both are
unknown and as they occur in different formations, they cannot be
easily identified at present ; the arms are three times divided; length
of cup, three lines and a half; of the arms, ten lines.

40 CANADIAN FOSSILS.

EXPLANATION OF Figures. Puars III.

Figure 5a. View of the left side, shewing the left anterior ray, which has the first
and second primary radials included in the cup.
5b. View of the anterior side.
‘¢ 5c. The posterior side.

Locality and formation—Hudson River group, Charleton Point,
Anticosti.

DENDROCRINUS SIMILIS, Billings.

(D. smmiuis, Report Geological Survey of Canada, 1856, page 267.)

Description —Cup, small, conical and sub-pentagonal; arms, long,
three or four times sub-divided, rather broadly rounded on the back,
and comparatively stouter than those of any of the above described
species. Of the two arms preserved in the specimen examined, one
remains single for a distance of two lines and a half, and then divides;
there are five joints in the undivided part; the other arm shews but
two joints in the part below the first bifurcation. The column for
seven lines below the basal is pentagonal, with round edges and
slightly concave faces; it is composed of alternately thick and thin
joints, nine of each in the space of two lines, diameter of column
nearly one line; length of arms sixteen lines, and the diameter at
the undivided part nearly a line on the back.

Locality and formation—Trenton limestone, City of Ottawa.

The last three species appear at first sight to be identical, but the
moment a magnifying glass is brought to bear upon them, their
differences become quite as apparent as those of the large species.
In D. acutidactylus the arms are exceedingly thin and sharp on the
back above the first division like the edge of a knife, and the column
is circular and composed of round edged joints, which at the distance
of one-half or three-fourths of an inch become nearly globular. In
D. proboscidiatus the column at the base of the cup is pentagonal with
the angles so strongly projecting, and the faces so concave that a
single joint has the form of a five-rayed star ; the arms, judging from
the fragments seen, were very similar to those in D. acutidactylus.

In D. similis the column is only different from that of D. probosci-
diatus by the unequal thickness of the joints, and in being more
regularly pentagonal ; its faces are only slightly concave, its arms
also are five times thicker.

CANADIAN FOSSILS. 41

DENDROCRINUS RUSTICUS, Billings.
Plate III. Figures 7a, 70.
(D. rusticus, Report Geological Survey of Canada, 1856, page 270.)

Description.—The base of the cup in this species is broad, like that
of D. conjugans ; the basal plates about as high as they are wide, the
sub-radials one-third higher than the basal plates ; the arm-plates a
little shorter than the sub-radials, and broader than high ; the azygos
inter-radial is about the size of one of the basal plates, and. bears three
or four small plates upon its summit; the column is round at its
junction with the basal plates, and composed of thin plates; but one
line and a half below it becomes pentagonal, with raised rounded
edges and concave faces; at the distance of two inches below the
base there are about three joints of equal thickness to one line in
breadth ; the arms appear to have been short; breadth of cup, two
lines and a half in one specimen and three lines in another; height
of latter to the top of the inter-radial, four lines and a half; the whole
surface is smooth. The specimens examined are imperfect, but to
each there are about three inches of the column attached.

EXPLANATION oF Figures. Puare III.

Figure 7a. A specimen very imperfect.
“7b. A small portion of the column, enlarged.

Locality and formation.—Trenton limestone, City of Ottawa.

DENDROCRINUS CoNJUGANS, Billings.
Plate IV. Figures 1a, 1b, 2a, 26.

(D. consucans, Report Geological Survey of Canada, 1856, page 268.)

Description.—In this species the column about one inch below the
base is round, smooth, and from half to two-thirds of a line in dia-
meter ; proceeding upwards it rapidly enlarges to two or three lines,
at the base of the cup, which is small, and not much broader at the

42 CANADIAN FOSSILS.

margin where the arms become free, than it is at the bottom; the
basal plates are low and broad, the sub-radials double the height of
the basals and the arm-bearing plates rather more than two thirds
the length of these latter ; the arms half the breadth of the plates on
which they stand, and broadly rounded on the back ; they all divide
at the height of about three lines, and again at the same distance
above ; there are three or four joints in each of the undivided por-
tions. The ray on the left-hand side of the base of the proboscis,
which in the generic description is said to have two of its plates
included in the cup, in this species has the second plate free, with
the exception that it is united on one side to the plates of the
proboscis ; it is however nearly as broad as the first radial plate upon
which it stands, and one-third wider than the first free joint of the
arm which rests upon it. This character connects Dendrocrinus with
Cyathocrinus, in which the second joint of the ray in question is
entirely free. The column as before mentioned is circular, broad at
the base of the cup, and rapidly diminishing in size for a short
distance below ; it is in this part smooth, but farther down enlarges
again, and is composed of thick round-edged compressed spheroidal
joints very similar to those of Heterocrinus Canadensis. In one perfect
specimen the height of the cup is three lines, the diameter of base
two lines and a half, and at the margin three lines and a half; length
of the arms to first division three lines and a-half, to second division
six lines; width of arm to second free joint one line, and of the
proboscis the same. In another individual this organ is wider than
the arm; in a third specimen the arms divide at the fifth joint, but
in every other respect it is the same as this species, although slightly
more slender.

EXPLANATION OF Figures. Prats IV.

Figure la. Anterior side.
“ 16. Column, a little enlarged.
«2a. Side view of a specimen.
‘* 26. Column of same, enlarged.

Locality and formation.—Trenton limestone, City of Ottawa.

CANADIAN FOSSILS. 43

' DENDROcRINUS JEWETTH, Billings.

Figure 15. View of the anterior side of Dendrocrinus Jewettii.

Description.—Cup, conical, six lines in height; arms, large, several
times sub-divided, broadly rounded or sub-carinate on the back.
The plates are all more or less convex, and appear to have a set of
obscure radiating ridges arranged as follows: 1st. On each of the
basal plates there are two ridges which run from the centre of the
plate upwards, and are continued to the centres of the two sub-
radials that rest upon its upper sloping sides. 2nd. On each of the
sub-radials there are four ridges, two of which are the continuations
of the ridges from the basal plates, while the other two run from
the centre of the plate upwards, and are continued on the first
primary radials to the bases of the arms. The rays consist each of
one large joint, included in the cup, and four smaller ones, above
which they are divided. The large joint of the left anterior ray
is hexagonal; the same joint in each of the other four rays is
pentagonal. The azygos sub-radial is heptagonal, and supports
upon its upper side a hexagonal azygos inter-radial, which, in its
turn, supports the proboscis. Column, unknown. Height of basal
plates, two lines; width at base of each, one line; width measured
between the two upper lateral angles, one line and a half; height
of sub-radials, three lines; width of first primary radial, two lines
and a half; height, two lines; the four succeeding joints of the arms
are each half a line high.

This species is allied to D. humilis and D. latibrachiatus, from both
of which it differs in having the plates convex and ridged.

44 CANADIAN FOSSILS:

It was discovered by Col. E. Jewett, of Utica, N. Y., and by him
kindly communicated to us for description. Through the researches
of this gentleman our knowledge of the Silurian fauna of North
America has been greatly extended. Many of the most rare and
interesting fossils figured in Hall’s Paleontology of New York are
his discoveries; .and it gives me much pleasure to dedicate this new
crinoid to him.

Locality and formation.—Bay of Quinte, Trenton limestone.

DENDROCRINUS CYLINDRICUS, Billings.
Piate III. Figures, 8a, 8b.

Description—Cup, small, two lines and a half in height, and about
the same in width at the margin ; arms, cylindrical, one line in width
at the base, divided above the third free joint; length of the undi-
vided portion, two and a half lines, each one of the three free joints
being nearly one line in length. The proboscis is large, equal to
the arms in height, and composed on the anterior side of large plates,
the first, second, third and fourth of which are each rather more than
one line in length. All the plates are smooth. The column is
round, smooth, and composed of very thin joints, which however
vary a little in thickness, ten in the length of one line. Length of
body and arms, one inch and one-fourth.

The above description of the column of this species refers to the
upper portion only. It seems probable that in the lower part it is
composed of thick, rounded joints, as I find a fragment of a column
of this latter character on the same piece of stone in which the
crinoid is imbedded.

EXPLANATION OF Figures. Puate III.

Figure 8a. Anterior side of D..cylindricus. That which appears to be a large
arm near the left side is the proboscis.
“ 8b. Part of the column, a little enlarged.

Locality and formation—Near the Toll-gate, St. Lawrence Street,
Montreal ; Trenton limestone.

CANADIAN FOSSILS. AS

PALHOCRINUS ANGULATUS, Billings.
Plate II. Figures 6a, 60.
(DENDEOCRINUS ANGULATUS, Report Geological Survey of Canada, 1856, page 269.)

Description—In this beautiful little crinoid the plates are orna-
mented with radiating ridges similar to those of Glyptocrinus decadac-
tylus. The cup is small, conical and pentagonal. From the centre
of each of the rather large sub-radial plates there proceed six
strongly-elevated ridges, one to the base of each of the two arms
above the plate, one to each of the two basal plates below it, and
one to each of the adjoining sub-radials. The arms are very slender,
sharp on the back, and at least twice divided; the three joints of
the column which remain attached to the specimen are pentagonal.
Length of cup, three lines; breadth at the margin, four lines.
Diameter of column, nearly one line.

EXPLANATION oF Figurus. Pate III.

Figure 6a. Left side of the only specimen discovered.
“6b. Column, enlarged.

Locality and formation.—Trenton limestone, City of Ottawa.

PALAOCRINUS RHOMBIFERUS, Billings.

Description.—This species is of nearly the same shape as P. angu-
latus, but differs in the arrangement of the surface-markings. In
P. angulatus the radiating ridges are so disposed as to encircle the
body with two horizontal rows of triangular spaces. In this species
however, in consequence of the absence of the transverse ridges near
the centre of the body, the spaces are rhomboids instead of triangles.
‘The ridges are also so broad in ithe ‘base that the separate plates
appear to be simply bevelled from ‘the centre to the edges. The
detached plates figured on plate, vol. i. Paleontology of New York,
under the name of Actinocrinus, resemble the sub-radials of this
species, but are larger. Only one specimen has been collected,
consisting of a perfect cup imbedded in a piece of limestone. The
arms are sharp-edged on the back, and twice divided. Length of
cup, three lines ; and of the arms, nine lines.

Locality and formation.—Trenton limestone, City of Ottawa.

46 CANADIAN FOSSILS.

PALZOCRINUS PULCHELLUS, Billings.

Description —The same as P. angulatus, but with a round column.
The surface of the specimen is a good deal eroded, and yet it can be
seen that the surface is radiated, as in P. angulatus. The column is
well preserved, and is one line wide at the base of the cup, from
which point it rapidly tapers to the thickness of half a line at the
length of four lines. Length of cup, three lines.

Locality and formation —One specimen from the Trenton limestone,
City of Ottawa.

Genus LecaNnocrinvs, Billings.

(Lecanocrinvs, Hall, Paleontology of New York, volume ii., page 199.)

FormMvta :

Basal plates, 3. Radials, 1X5.
Sub-radial plates, 5. Azygos inter-radials, 1-3.

Generic characters——In this genus there are three basal plates,
one of them pentagonal and the other two hexagonal; in the second
series there are five sub-radial plates, two of which are supported
by the two hexagonal basal plates, while the other three alternate
with these latter. Alternating above the sub-radials are five primary
rays of three joints each, and above these, ten secondary rays.
Some of the species have several small inter-radial plates in one or
more of the divisions between the primary rays.

I have placed the following species in the above genus, although
it appears probable that some other disposition should be made of
them. The specimens are not sufficiently perfect to enable me to
make out all the characters; and as they are more nearly related to
Lecanocrinus than any other Silurian genus, it seems to be the better
course to arrange them in that group provisionally.

CANADIAN FOSSILS. 4l

LECANOCRINUS ELEGANS, Billings.

Plate IV. ‘ Figures 4a, 40.
(L. Eunaans, Report Geological Survey of Canada, 1856, page 278.)

Description.—Cup, small, conical, three lines in height from the
base to the upper margin of the first primary radial plate, at which
level the breadth is also about three lines; the breadth of the base
is one line and a half, and the top of the column scarcely less; the
first primary radials are a little broader than high, and rendered
slightly heptagonal by the truncation of their upper lateral angles ;
the second primary radials are narrower and quadrangular, or
obscurely hexagonal; the third are pentagonal ; the length of each
is about a line and a half. The third in each of the three rays
exposed in the only specimen seen, supports two secondary rays of
five joints each, and then divides into two tertiary rays; these latter
are again divided. The rays above the fourth division are articulated
in two series. Between the primary rays are several small inter-
radials. The column is circular, with round-edged joints, from four
to six in one line; length of ray from the base of first primary radial
to the extremities, one inch and one fourth.

EXpLANATION OF Figures. Puate IV.

Figure 4a. A specimen shewing one of the hexagonal basal plates.
« 4b. Several joints of the column, a little enlarged.

Locality and formation.—Trenton limestone; City of Ottawa.

LECANOCRINUS LAVIS.

Plate IV. Figure 3a.
(L. travis, Report Geological Survey of Canada, 1856, page 278.)

Description —This species is shorter than the preceding, and has
only four joints instead of five in the secondary rays; the upper part
of the column is round and smooth. In other respects there is much
resemblance between the two, but still I think them distinct.

EXPLANATION OF Figures. Puate IV.

Figure 3a. A specimen slightly crushed.

Locality and formation. —Trenton limestone; City of Ottawa.

48 CANADIAN FOSSILS.

Genus HETEROCRINUS, Hall.

(Heterocrinvs, Hall, Paleontology of New York, volume i., page 278.)

Figure 16. ‘Diagram of the structure of the genus Heterocrinus.

Generic characters—The species of this genus are small, and,
including the arms, long and nearly cylindrical crinoids. The base
is composed of five plates, above which are five long rays, without
any intervening sub-radial plates. The number of radial plates in
each ray is variable. The cup appears to consist of the primary
radials, while the free rays or arms commence with the first plates
of the secondary rays. There are one or two small azygos inter-
radials, but no regular inter-radials. The arms are pinnulated.

HETEROCRINUS CANADENSIS, Billings.

(Compare H. simplex, Hall, Paleontology of New York, volume i., page 280.)

Description —Sub-cylindrical or elongated, fusiform; length, inclu-
ding the rays, from one to two inches; diameter at half the length,
from three to four lines. The base in the large specimens is about
one line and a half in diameter, and the body gradually enlarges to
about three lines at that point where the rays divide. The diameter
above is always greater, the extent depending upon the amount of
expansion of the rays in the particular specimen examined. The
basal plates are scarcely a line in height; the length of the undivi-
ded portions of the rays in the large individuals is about three lines.

CANADIAN FOSSILS. 49

The right anterior ray consists of three joints, the first equal in
length to the other two, and with one of its angles truncated where
it is in contact with the azygos inter-radial. The left anterior ray
has four joints, the second being the longest, and having one of its

angles truncated to support the inter-radial. The other three appear
to consist each of four equal joints. The upper joint of each ray
is pentagonal, and supports two secondary rays, which continue
single to their extremities. The azygos inter-radial is oblong, higher
than wide, five-sided, two of the sides meeting to form an obtusely-
pointed lower extremity, which rests wedge-like between the trun-
cated angles of the first joint of the ray upon the left, and the second
joint of the ray on the right; its upper side is horizontal and supports
another plate, which is probably the base of a proboscis. The
secondary rays, ten in number, consist each of a series of oblong,
quadrangular joints, usually one line in length and two-thirds of a
line in breadth.

There is a row of long pinnulz upon each of the inner margins of
each ray; they rise upwards, nearly parallel with the rays, instead
of projecting at nearly right angles, as in other species. The column
is round and smooth at the base of the pelvis, below which it tapers
and becomes very slender at the distance of one or two inches, then
slightly larger and composed of compressed globular joints, the
rounded edges of which, to the eye, present a bead-like appearance.
The longest column seen with the head attached was fifteen inches;
and, as it was broken off below, it had been probably several inches
longer. The diameter is usually somewhat less than a line, and there
are about seven joints of equal size to two lines in length. The
smooth, slender, upper portion of the column, near the base of the
cup, is generally half a line or a little more in diameter, expanding
to twice or three times this size at the base.

H. simplex, according to Professor Hall, has the column at the
base of the cup pentagonal, but is otherwise closely allied to
H. Canadensis. (See description of H. simplex in the Paleontology
of New York, volume i., page 280.)

EXPLANATION OF Figures. Puare IV.

Figure 5a. A specimen with part of the column attached.
*« 5b. Portion of the column, enlarged.
5c. Anterior side of a different specimen.
«¢ 5d. A specimen which has the pinnule preserved.

Locality and formation—Trenton limestone, Ottawa and Montreal.
D

50 CANADIAN FOSSILS.

HETEROCRINUS TENUIS, Billings.

Plate IV. Figures 6a—66.

(H. tenuis, Report Geological Survey of Canada, 1856, page 273.)

Description. — Much smaller than H. simplex; arms, long, very
slender, and several times divided; column, very obscurely penta-
gonal, composed of sub-globular joints; proboscis, extending nearly
to the apices of the arms; length, including the arms, from ten to
sixteen lines; without the arms, from one and a half to two and
a half lines; diameter at base of arms, about two lines; of column,
at base of cup, half a line.

It is not certain that this species should be referred to the genus
Heterocrinus. The plates of all the specimens in the collection are
so closely united that their number and arrangement cannot be
satisfactorily made out. The weight of the evidence is in favor of
the genus under which I have placed it. The species, when several
times attentively examined, is easily distinguished from H. simplez.
In that species the column, for a short distance below the cup, is
smooth and slender, and it enlarges suddenly from a few lines below,
until it forms rather a broad base for the pelvis to stand upon. But
in H. tenuis the column continues moniliform to the base of the cup
and without enlarging, but on the contrary is rather less in diameter
at the point of contact than it is below. In one specimen there are
forty two joints in the first nine lines from the pelvis, and some
irregularities in the size can be seen. They are thinner near the cup
and gradually become thicker, so that at two inches from the pelvis
there are only sixteen in half an inch. The arms, although much
more slender than those of H. semplex, usually lie folded together, or
but slightly separated.

EXPLANATION OF Figures. Pate IV.

Figure 6a. A specimen with part of the column.
“ 6b. A few joints of the column, enlarged.

Locality and formation —Trenton limestone, Ottawa and Montreal.

CANADIAN FOSSILS. al

HETEROCRINUS INZQUALIS, Billings.
Plate IV. Figure 7a.

Description.—Cup, pointed at the base; rays, large, rounded on
the back, and inequally divided. In the specimen figured, the two
first primary radial plates which can be seen are long and nearly
triangular, their lower acute angles meeting in the base of the cup
and their upper straight sides supporting free rays or arms. Only
three of the rays are visible in the specimen, the others being
imbedded in the matrix. One of these (partly shewn at the left side
of the figure,) appears to be simple or undivided ,throughout. It is
nearly cylindrical, and consists of a series of large, transversely
oblong joints, one line and one fourth in width and two thirds of a
line in height. Its lower extremity is concealed, and I have not
been able therefore to ascertain whether or not it originates in the
base of the cup. The central ray (of the figure) divides above the
third joint into two equal secondary rays, which are also several
times subdivided. In these subdivisions of the secondary rays,
however, the branches are of an unequal size, one of them in each
instance being about one-fourth the thickness of the other. The
other ray (partly exposed in the specimen,) is undivided from the
base to the fifth joint inclusive, above which it is buried in the stone.
The surface is minutely granular.

I have placed this remarkable species in Heterocrinus provisionally,
as it most resembles species of that genus. When its structure
shall have been ascertained, it may be necessary to refer it to some
other genus.

Locality and_formation.—Trenton limestone, Ottawa.

HETEROCRINUS ARTICULOSUS, Billings.
Plate IV. Figure 8.

Description —Of this species we have only a single ray, which
much resembles one of the rays of H. inequalis, but is nevertheless
decidedly distinct. The secondary rays are irregularly jointed, the
plates where the branches are given off being broader than elsewhere.
In consequence of this character the rays have a peculiarly knotty
appearance. It is probable that this species and H. cnequalis will,
when all their characters are known, constitute a new genus.

Locality and formation.—T renton limestone, Ottawa.

52 CANADIAN FOSSILS.

Genus CLEIOCRINUS, Billings.

(Cuz1ocrinus, Report Geological Survey of Canada, 1856, page 276.)

Cy
eS, Se-s
Osensese
) {

Figure 17. Diagram of the structure of the cup in the genus Cleiocrinus.

Generic characters.—Cup, large, conical or pyriform ; basal plates,
five; rays, five, alternating with the basal plates; the third plate of
each ray is pentagonal and bears two secondary rays, which are
several times divided above. Between two of the rays a single
vertical series of azygos inter-radial plates extends from the base to
the margin of the cup. The azygos plates and rays are all firmly
anchylosed together by their lateral margins up to the height of the
fifth or sixth sub-division. The column is pentagonal or nearly round.

This genus has the structure of a Pentacrinus, with numerously

divided arms all soldered together in the walls of the cup.

CANADIAN FOSSILS. 53

CLEIOCRINUS REGIUS.

Plate V. Figures 1la-Ig.

(CxiE10cRiInus REGIUS, Report Geological Survey of Canada, 1856, page 277.)

Description—Cup, elongate, conical, gradually expanding from
the base until near the top, where it is slightly contracted. The
margin supports about forty long, very slender, tentaculated, free
rays. At first sight there appear to be ten small basal plates, but
upon examination five of these are found to be the first plates of the
five rays which rest immediately upon the upper joint of the column;
the other five are the true basal plates. Four of these latter are
pentagonal, and the fifth, which supports the series of inter-radials,
is nearly square; height of each basal plate, one line; breadth, the
same ; the small radial plates which rest on the column between
the basal plates are a little broader than these latter, but not so
high ; the column is pentagonal, and the basal plates are placed
upon the angles of the upper joint, while the bases of the rays are
situated upon the straight edges: there are about two joints of
the column to one line, and they are alternately thicker and thinner ;
the column near the lower extremity becomes round and suddenly
expands into a broad base of attachment. |

The surface of the cup is nearly smooth, slightly marked by
obscure, vertical, rounded ridges along the centres of the rays and
of their sub-divisions.

Length of cup, one inch and three-fourths; breadth near the
margin, about oneinch; diameter of column, from two to four lines.
Nearly all the large pentagonal columns in the Trenton limestone
at the City of Ottawa belong to this species.

EXPLANATION OF Figures. Puate V.

Figure la. <A nearly perfect cup of this species.
‘1b. The base, shewing the small basal plates, with the quadrangular first
primary radials between them. ;
«Ic, 1d, le, and 1f. Fragments of the column.
“( 1g. The base of the column.

Locality and formation.—Trenton limestone, City of Ottawa.

54 CANADIAN FOSSILS.

CLEIOCRINUS GRANDIS, Billings.

Plate V. Figures 2a-2c.

Description.—The column of this species is large, obscurely pen-
tagonal, and composed of thin joints, every alternate one of which
is about one fourth of a line wider than the one on each side of it.
In consequence of this inequality in the size of the joints the column
is closely annulated with slightly projecting rings, from six to eight
in three lines. When perfect it is rounded-pentagonal, but when
erushed it divides into five longitudinal lobes, as represented in
figure 2b. Each joint appears to be composed of five pieces, and
the articulating surfaces are striated with numerous fine, curved,
radiating ridges. The radix or base of attachment of the column
consists of a number of large roots, which appear to be composed of
small polygonal plates. The alimentary canal is very large and
nearly circular.

These columns have so nearly the structure of those of C. regius,
that I have no doubt they belong to a species of that genus.

EXPLANATION OF Figures. PLATE V.

Figure 2a. Portions of two individuals of this species, which appear to have
grown upon the same spot.
«“ 26. Fragment of a column, crushed.
“ 9c, Transverse section, shewing the large alimentary canal.

Locality and_formation.—Trenton limestone, Ottawa.

CLEIOCRINUS MAGNIFICUS, Billings.
Plate V. Figure 3.

Description.—In this species the column is nearly round and
composed of thin joints, of which there are from six to eight in two
lines. The alimentary canal is pentagonal, and six lines in diameter
where the column is nine lines. The cup has never been seen, but
the size and form of the fragments of the stalk are sufficient to
distinguish this species from any other in the Trenton limestone.
It appears to belong to the genus Cleiocrinus. Diameter of column,
from nine lines to one inch.

Locality and formation.—Trenton limestone, City of Ottawa.

CANADIAN FOSSILS. oo

Genus GLYPTOCRINUS, Hall.

(Guyprocrinvs, Hall, Paleontology of New York, volume i., page 280.)

FORMULA :

Basal plates, 5. | Regular inter-radials, 6.
Radial plates, 3X5. Azygos inter-radials, 7 or more.

Figure 18. Diagram of the structure of the cup in the genus Glypiocrinus.

Generic characters—Cup, pyriform, globular or oval, in some spe-
cies very large; arms, long, densely fringed with pinnule; base,
composed of five plates, which are either pentagonal or hexagonal ;
regular inter-radials, usually six; azygos inter-radials, seven or more ;
column, round or sub-pentagonal, strongly annulated or moniliform
in all the species known.

The plates of the species of this genus are flat, thin, and either
smooth or ornamented with radiating ridges, striz or raised margins ;
the large joints of the columns are often nodulose. In the Black
River and Trenton limestones in Canada, the remains of several
species are exceedingly abundant, but usually reduced to mere frag-
ments of the plates and column. At the city of Ottawa, where these

56 CANADIAN FOSSILS.

rocks are exposed on a large scale, three of the species hereinafter
described, G. priscus, G. ramulosus, and G. marginatus, appear to be
more common than at any other locality yet examined. The heads
are frequently found there in a fragmentary state, but good speci-
mens are rare. G. priscus is the only head collected in the Black
River limestone, but it also occurs in the Trenton. I have met with
G. lacunosus near the top of the Trenton limestone only. G. ornatus
is found about the middle of the deposit, rather common, and in
fewer numbers upwards to the Utica slate. There is a sixth species
which also occurs at Ottawa, but is only known by its very charac-
teristic sub-pentagonal column.

GLYPTOCRINUS PRISCUS, Billings.

Plate VII. Figures la-if

(G. priscus, Report Geological Survey of Canada, 1856, page 287.)

Description—The cup of this species is pretty regularly oval,
covered with smooth plates and surmounted by ten long undivided
fingers or free rays, which are densely fringed with two rows of
pinnule. A strong rounded carina, or ridge, runs up each of the
primary rays, and, dividing into two upon the centre of the third
plate, sends a branch up each of the secondary rays to the base of
the fingers ; the carine are also divided upon each of the basal plates,
and coalesce into one on the centres of the first primary radial plates ;
in the azygos inter-radius a sixth ridge ascends to the top of the
cup, dividing the space into two parts about equal; it bifurcates
below on the centre of the large azygos, one branch proceeding to
the centre of each of the two contiguous first primary radial plates.
The basal plates are of a moderate size, but the first radials are large,
broad, and in contact with each other by their upright lateral
margins. The joints of the free rays are thin and very closely set.
The rays are also rather broadly rounded on the back. As to the
column, the only perfect head in the collection has but a single joint
attached to its base, but the columns found associated with it and
also those which have been observed in the Trenton limestone at
Ottawa, along with the fragments of the heads of individuals of this
species, are round, with the large joints rather thick and rather
nodulose. I think this species grew to a very large size; but the
evidence is not sufficient to connect positively the small specimen

CANADIAN FOSSILS. 57

examined with the large ten-fingered fragments found in the Trenton
limestone.

EXPLANATION OF Figures. Puarte VII.

Figure la. View of the posterior side of G. priscus.
oe 1b. Anterior side of the same specimen.
se le., 1d., le., if Columns found associated with 1a.

Locality and formation.—One small perfect head collected at the
upper mouth of the cave at the fourth chute of the Bonnechére, in
the County of Renfrew, in the Black River limestone. Fragments
of the heads and columns apparently referable to this species are
common in the Trenton limestone at Ottawa.

GLYPTOCRINUS RAMULOSUS, Billings.

(G. Ramunosus, Report Geological Survey of Canada, 1856, page 258.)

Description.—The cup of this species very much resembles that of
G. priscus. It is covered with smooth plates, and the primary and
secondary rays are strongly keeled, but the base is broader, the basal
plates smaller in proportion to the size of the body, and there are
twenty free arms springing from the margin instead of ten, as in G.
priscus. The arms also are several times bifurcated at various dis-
tances from the top of the cup, while those of the former species
remain single to their extremities; the pinnule are in two rows, and
from one-fourth to three-fourths of an inch in length; the ossicula of
the arms are very thin, and interlock with each other so deeply that
each seems to extend completely across, giving the appearance of
but a single series of joints where in fact there are two. Near the
base of the arms there are two joints in about one line, but higher
up there are from four to eight in the same length. The arms are
regularly rounded on the back, and comparatively slender, being
scarcely more than one line in diameter at the base of the largest
specimens. In the specimens examined four of the plates of each of
the secondary rays are included in the general test of the body. The
column is round, and at the base of the cup the large projecting
joints are thin, sharp-edged, and crowded close together ; they gra-
dually become farther apart as the distance from the base of the cup
increases, until at length they are from one to three lines removed
from each other. Between these large joints the column is composed
of very thin plates with crenulated margins, the projecting teeth of

58 CANADIAN FOSSILS.

one plate fitting into the corresponding notches of those in contact
with it above and below. The edges of the large joints are nodulose,
and the column is much larger at the base of the cup than at its
lower extremity. One specimen tapers from one-fourth of an inch
to one-eighth in a length of fifteen inches.

The form of the alimentary canal appears to vary in different parts
of the same column, being usually more or less star-shaped, but
sometimes circular. The separate large joints are generally seen in
the shape of flattened rings, with the outside margin thick and
rounded, but thinned down to a sharp edge around the perforation
of the centre.

The columns of this species very much resemble those of Schizo-
crinus nodosus (Hall, Paleontology of New York, vol. i., pl. 10), and
were always so called in Canada, until a number of specimens were
found with the heads attached. The figures and description of that
species however given by Professor Hall, show that it had four plates
in the primary rays, and must be therefore not only specifically but
generically distinct from G. ramulosus. I think that a large propor-
tion of those great columns so common in the Trenton limestone on
the Ottawa should be referred to this species and to G. priscus. |
Specimens four or five feet in length are sometimes seen in the
quarries, and some of the crushed heads, including the arms, are
seven inches in length.

A highly interesting specimen in the cabinet of Dr. Van Cortlandt
of the city of Ottawa, consists of the inside of a cup two inches
and a half in length and one inch and seven-eighths in diameter,
at the base of the free arms. It had been completely embedded
in the stone, but by some means the body has been extracted,
leaving all the plates lining the cavity in their natural position.
Each of the plates has a small tubercle in its centre, on the inside.
The impression of a fragment of the column one inch and a half in
length from the base of the cup downwards still remains. The
characters of the column are precisely those of many of the large
ones usually seen without the heads attached. If therefore any of
these large columns belong to this species, then in their advanced
age they must have lost their nodulose character, because they are
smooth instead of nodose, as is the case with the smaller specimens
in the collection of the Survey which have the heads attached. It
appears to me that in all the species of Glyptocrinus the columns
were ornamented until past the middle age, and that afterwards they
became plain.

CANADIAN FOSSILS. 59

EXPLANATION OF Figures. Puatss VII. anp VIII.

Plate 7, figure 2a. A cup of medium size.

« 2b. Portion of the column near the base of the cup.

‘© Qc-2f. These figures represent different parts of a very long column.
Plate 8, figure la. A crushed specimen, with part of the column attached.

‘© 15. The column of 1a, enlarged.

* Ie, 1d. Columns found along with la.

Locality and formation.—Trenton limestone, City of Ottawa, Island
of St. Joseph, in Lake Huron.

GLYPTOCRINUS MARGINATUS, Billings.

Plate IX. Figure la.
(G. MARGINATUS, Report Geological Survey of Canada, 1856, page 260.)

Description.—The plates of this fine species are all margined by a
strong elevated border, the effect of which is to give to the surface
a beautifully reticulated appearance. The only specimen in the
collection is crushed, but then the size of the plates near the bottom
shows that it had a broad, rounded base, and that its general form
was sub-globular. The azygos inter-radial space contains ten plates
below the level of the base of the secondary rays; the rays are all
carinated, and there is also an upright row of small plates (in the
centre of the azygos inter-radial space) which exhibits a faint keel.
There are four or five of the secondary radial plates included in the
cup. A piece of the column two inches and a half in length remains
attached, and shows that the large joints at the base of the cup of
this species were much thicker, and consequently not so sharp-edged
as those occupying a similar position in the other species.

The length of this cup from the base to the free arms is one inch
and a half, and the breadth about the same. The column is four
lines in diameter, and in the length of two inches and a half there
are twenty-one large joints with the same number of others a little
smaller, each situated half way between two of the largest. The
arms are not preserved in the specimen.

This species also grew to a large size, and was closely related to
both G. priscus and G. ramulosus.

EXPLANATION OF Figures. Puare IX.
Figure la. View of the only specimen collected.

Locality and formation.—Trenton limestone, City of Ottawa.

60 CANADIAN FOSSILS.

GLYPTOCRINUS ORNATUS, Billings.
Plate IX. Figure 2a.
(G. ornatus, Report Geological Survey of Canada, 1856, page 260.)

Description—In the specimens of this species that have been
collected the cup is broad-oval, the base well rounded, but narrower
than the upper extremity; the rays (as in the other species) are
keeled, and there are ten long, slender, undivided free arms, as in
G. priscus. Each of the plates is ornamented with five or six sharp
ridges, which radiate from the centre, thus covering the body with
numerous stars with triangular interspaces. The column is round,
and the large joints are thin, sharp-edged, and distant from each
other half a line at and near the base of the cup in a specimen of
the ordinary size.

Length of the cup in several specimens, a little more than half
an inch; diameter at the base of the free rays, about the same ;
diameter of column at the base of the cup, about one line.

The surface ornament of this species is very like that of G.
decadactylus (Hall) of the Hudson River group; but there is a very
decided difference in the form of the columns of the two. Those
figured by Professor Hall have the large joints very thick and
rounded, while in G. ornatus they are exceedingly thin and sharp-
edged ; some of our specimens are very like the figure of G. basalis
(McCoy), given on page 180 of Sir Roderick Murchison’s Siluria,
1st edition. In Sedgwick and McCoy’s British Paleozoic Rocks,
(p. 57) however, that species is described by Prof. McCoy as having
the pelvic plate immediately below the large inter-radial space,
hexagonal, and supporting upon its upper truncated margin the
large inter-radial. In our species all the pelvic plates are very
small and pentagonal. To both the English and New York species
ours is evidently closely allied.

EXPLANATION OF Figures. PLate IX.

Figure 2a. Anterior side of a specimen of G. ornatus.

Locality and formation—Upper half of the Trenton limestone,
City of Ottawa.

CANADIAN FOSSILS. 61
GLYPTOCRINUS LACUNOSUS.
Plate VIII. Figures 3a-3e.
(G. Lacunosus, Report Geological Survey of Canada, 1856, page 261.)

Description.—This species is characterized by its very large basal
plates, one of which, that beneath the azygos inter-radial space, is
hexagonal, and supports upon its upper truncated edge the first
azygos inter-radial. The surface of the body is completely covered
with small rugose pits and wrinkles; the rays become free at the
second or third secondary radial plate ; they divide immediately after
becoming free, at least once, perhaps again above, but the specimens
do not shew them perfectly above the first sub-division.. The body
is sub-globular, about three-quarters of an inch in length, and the
same in breadth.

The column is round, and when once carefully examined is easily
distinguished from that of any other species occurring in the Trenton
_ limestones. The large joints are proportionally very broad and
projecting, while the constrictions between them are wide and deep.
At the distance of frum six to ten inches from the base of the cup
the large joints disappear altogether, and the column becomes
smooth, like that of the genus Rhodocrinus. In one specimen, at
the distance of three inches from the base of the cup, the large
joints are nearly one line in thickness at their edges, and are two
lines distant from each other ; they are also two and a half lines in
diameter ; the constricted portion of the column between them is
scarcely one line.

EXPLANATION OF Figures. Pats VIII.

Figure 3a. A specimen with part of the column attached.
“« 36. Fragment of a different specimen.
¢ 3c, 3d, 3e. Columns of this species.

Locality and formation—Upper half of the Trenton limestone,
City of Ottawa.

RHODOCRINUS PYRIFORMIS, Billings.
Plate VI. Figures 1a-1d.
(THYsANoCRINUS [RHODOcRINUS] PyRIroRMIs, Report Geol. Survey of Canada, 1856, p. 263.)

Description.—Cup, conical or pyriform, the adult specimens about
two inches in length and one inch and a half in their greatest

62 CANADIAN FOSSILS.

diameter, which is near the base of the free rays. The basal plates

are pentagonal, with an obscurely-rounded ridge across their base ;

sub-radials, hexagonal, each supporting upon its truncated upper
margin a large inter-radial. The first primary radial on each side of
the azygos inter-radial space is hexagonal, the other three are penta-
gonal; the second plates in the rays are hexagonal, and the third
heptagonal ; each of the latter supporting upon its upper sloping
edges the bases of two secondary rays, which become free at the

third or fourth plate, thus furnishing ten arms, which divide at not

quite one-fourth of an inch from their base, and again at half an inch ;_
the full grown arms are again subdivided, some of them once, others

twice. The arms are comparatively short, not exceeding two inches

in length in a specimen whose cup measures one inch and a half in

length. The ossicula which constitute the double series of joints of
the free rays or arms, are obtusely cuneiform, the two rows inter-

locking with each other so slightly that the points of the joints

extend but a short distance across the centre of the back of the

arm ; there are two ossicula to one line in length in that portion of
the arm at the base which is situated next the cup, and below the

first sub-division; the arm here is scarcely one line in thickness.

All the plates are smooth or slightly granulated on their surface ; in

some of the specimens there is a trace of an obscurely-elevated

margin round the plates, and there is also a broadly-rounded keel,

not very prominent, upon each of the primary and secondary rays.

The column is round, slender, annulated, with thin but round-

edged projecting joints, for several inches below the bottom of the

cup ; it then becomes smooth, and continues of an uniform size to

the base of attachment, which consists of a number of root-like

branches. The annulated portion of the column is usually found a

little curved, but the smooth, cylindrical portion is always straight,

and in this part there are about ten joints to two lines of the length ;

near the cup there are three or four annulations to two lines. The

diameter of the column is from one and a half to two lines and

a half, and the length varies greatly ; one specimen, a very perfect

impression of the head, column and root, all in their natural connec-

tion, measured but seventeen inches in length ; a fragment of the

smooth portion of a column still lying in the rock measures thirty-
seven inches and a half. At Ottawa, in the upper part of the
Trenton limestone, there are fragments of smooth, round columns,

four or five lines in diameter, which appear to be a large variety of
this species.

CANADIAN FOSSILS. 63

EXPLANATION OF Figures. Puate VI.

Figure la. A specimen with part of the column attached.
‘¢ 1b, le. Crushed specimens.
“ld. The radix of this species.

Locality and formation.—Trenton limestone, City of Ottawa, plen-
tiful ; also in the upper part of the same formation, around the base
of the mountain at Montreal, where the columns are rather common.

RHODOCRINUS MICROBASALIS, Billings.

Plate VI. Figure 2.

(Taysanocrinus [Ruopocrinus] MicroBasauis, Rep. Geol. Survey of Canada, 1856, p. 264.)

Description—The specimens for which the above specific name is
proposed are about five-eighths of an inch in height, and the same
or a little more in breadth at the top. They are cup-shaped, and
uniformly expanding from the narrow base upwards. The basal
plates are so small that they can only be well seen when the column
is removed. The rays are keeled, and all the plates of the body
exhibit obscure, radiating ridges, somewhat similar to those of
Glyptocrinus ornatus, but not so prominent. The column is round,
annulated in its upper and smooth in its lower part. I have not
seen either the root or the arms.

This species is closely allied to R. pyriformis, but differs in its
much smaller size, in the comparative minuteness of the pelvic
plates, and also in the character of the surface. R. pyriformis is a
large, smooth species, but this one has a surface ornamented with
stars, only well seen however on good specimens.

Locality and formation.—Trenton limestone, City of Ottawa.

Genus RETEOCRINUS, Billings.

Generic characters.—This remarkable genus has no perfectly formed
plates. The cup consists of a reticulated skeleton, composed of
rudimentary plates, each consisting of a central nucleus, from which
radiate from three to five stout processes. Of such plates there are
five in the basal series, five in the sub-radial, and five in the radial
series. On the azygos side the sub-radial has five processes; the
others have four each.

64 CANADIAN FOSSILS.

The principal difference between this genus and such genera as
Dendrocrinus, Perocrinus, Pal@ocrinus, and Cyathocrinus, consists in
the incompleteness or rudimentary character of its plates. The
arrangement of the parts of the skeleton is the same.

‘

RETEOCRINUS STELLARIS, Billings.
Plate IX. Figures 4a—4e.

Description—The cup of this species appears to be about five
lines in height and six lines in width. The projecting processes of
the plates, and also the joints of the arms to first bifurcation, are
rounded on the outside, and half a line in thickness. The first joint
of the right anterior ray (which is the first primary radial,) has three
processes, the upper one of which supports an arm, while the two
lower rest, one of them on one of the upper processes of the azygos
sub-radial and the other upon a process of the right anterior sub-
radial. It is probable that the other rays are constructed and
situated in nearly the same manner. The azygos sub-radial has five
processes, three above and two below. The central of the three
upper processes supports an upright series of joints (as represented
in figure 4a, plate 9). If this series of joints constitute a true arm,
then there must be six arms in this species. The right arm divides
above the fourth joint; I have not seen the other arms distinctly.
The spaces between the arms are occupied by numerous small
stellate plates, which may have belonged either to an integument
connecting the arms, or to the covering of the abdomen. The
column is round, and composed of very thin plates near the base of
the cup. At the distance of about one inch and a half below the
base of the cup the joints alternate in thickness.

None of the specimens collected are pertect, and the characters of
the species therefore have not been fully ascertained.

EXPLANATION OF Figures. Puate IX.

Figure 4a. View of the anterior side of a specimen.

«« 46, A specimen retaining a piece of the column; 4c, several of the joints
enlarged. They appear to be nearly equal in size, and sharp-edged
at the base of the cup.

«Ad, 4e. Fragments of this species.

[In 4a and 4e the small stellate plates between the arms are represented. ]

Locality and formation.—Trenton limestone, City of Ottawa.

CANADIAN FOSSILS. 65

RETEOCRINUS? FIMBRIATUS, Billings.
Plate IX. Figures 3a—3c.

Description—Length of the only specimen discovered, including
the arms, about fifteen lines; basal plates, minute; sub-radials, one
line in height ; arms, several times divided and furnished with pin-
nule. At the apex of each of the basal plates there is an aperture
half a line in width, and another of the same size at the lower angle
of each first primary radial. The primary rays, so far as they have
been observed, consist each of three plates, the first heptagonal, the
second hexagonal, and the third pentagonal,—the spaces between
them filled with very small plates. A single joint of the column
remains attached to the base of the cup. It is pentagonal, with
slightly concave faces and rather sharp angles.

The specimen is very imperfect, and it is with much doubt that I
refer it to the genus Reteocrinus.

EXPLANATION OF Figures. Puate IX.

Figure 3a. The only specimen discovered.
“¢ 3b. The base, enlarged; the unshaded pentagonal space shews the form of
the upper joint of the column.
“¢ 3c. One of the arms, with some of the pinnule attached, enlarged.

Locality and formation—Hudson River group, Charleton Point,
Anticosti. ;

SYRINGOCRINUS PARADOXICUS, Billings.
Plate X. Figure 14.

Description—Of this crinoid no perfect specimens have been
collected. The fragment figured exhibits in the side exposed two
series of polygonal plates, so arranged that they appear to constitute
part of a tube, one half of which (probably composed of two other
series of plates,) is buried in the stone. At one-extremity (the lower
end in the figure,) this tube is one line and and a half in diameter ;
but as it appears to be flattened by pressure, its thickness did not
probably much exceed one line when not distorted. At the other
end it seems to be somewhat larger, but this may be owing to the
separation of the plates. At thisextremity also there appears to be

E

66 CANADIAN FOSSILS.

attached to the main body of the tube an additional part, composed
of numerous small, elongated, irregular plates, placed transversely.
That this curious fossil is part of a crinoid, I have not the least
doubt; and further, it seems quite certain that it does not belong
to any known genus. The above generic and specific names are
proposed for it provisionally.
Locality and formation.—Trenton limestone, Beauport, near Quebec.

Genus COMATULA.

Memoir on the Star-Fish of the genus Comatula, demonstrative of the
Pentacrinus europaeus being the young of our indigenous species.
By Joun V. THompson, F.L.S., Deputy Inspector-General of
Hospitals. Communicated by Sir James M‘Grigor, F.R.S. *

[Extracted from Jameson’s Edinburgh New Philosophical Journal, vol. xx., p. 295.]

‘Tf we were told by any traveller that he had visited an unknown
region, where the animals dropt their eggs on trees and shrubs, which
there fixed themselves and shot up like parasitic plants on a long stem,
gradually evolving, at their extreme end, member after member and
function after function, until the young animals became so perfect
as to resemble their parents in every essential point,—when their
attachment to the connecting foot-stalk was dissolved, and they
became free and locomotive, and betook themselves to the wandering
life of the parent stock ! few could be got to believe facts so incredible,
and so much at variance with the course of nature, as made manifest
everywhere and from all time; but if established on incontestable
evidence, the highest degree of surprise and admiration would neces-
sarily supplant our incredulity,—voyages would be undertaken, and
the curious of every country would flock to witness such an extraor-
dinary anomaly, at the greatest risk and expense. If, then, a fact so
contrary to our experience relating to the superior classes of animals
should be capable of exciting so great a degree of interest, it may be
presumed that an analogous circumstance, now for the first time
actually discovered in an animal belonging to one of the inferior
classes, must be considered at least as highly worthy of the attention
of the philosophic naturalist.

“Jt is no uncommon thing, in the inferior classes of the animal
kingdom, to find animals permanently attached from the period of
their birth, and during the whole time of their existence, familiar
examples of which we have in the oyster, anomia, and various other

* Read before the Royal Society of London, in J une, 1835.

68 COMATULA.

bivalve shell-fish, and in numerous compound animals of the classes
Zoophyta and Infusoria. J have also shewn, in my memoirs on the
Cirripedes, examples of animals being free and locomotive in their
first stages, and afterwards becoming permanently fixed; but an
animal growing for a period as it were a flower, fixed by its stem,
and then dropping from its pedicle and becoming, during the re-
mainder of its life, free and locomotive, is not only new, but without
any parallel in the whole range of the organized part of the creation.
No wonder, then, that any naturalist, on the first discovery of the
young animal in its first or fixed stage of existence, should consider
it as belonging exclusively to those which are known to be perma-
nently fixed; analogy would permit no other conclusion to be formed,
and consequently it could be classed with none other except the
Crinoideee, one known genus of which tribe participates with
Comatula in being locomotive in its advanced stage; so that this
circumstance connects all these animals into an inseparable group,
with which the present state of our knowledge will not permit us
to associate any other of the Asteriz.

Fig. ish .

Figure 19. Adult Comatula decanemos.

‘‘ When, therefore, I formerly described the young of the Comatula*
as a new species of Pentacrinus, no person could have suspected so
anomalous and unexpected a result, as that it was the young state of
this curious star-fish, an animal not only free, but leading the most
vagrant life of any of the tribe with which it has hitherto been asso-
ciated by naturalists,—at one time crawling about amongst submarine
plants, at others floating to and fro, adhering to thin fragments by
means of its dorsal claspers, or even swimming about after the

* Memoir on Pentacrinus europeus. Cork, 1827.

COMATULA. 69

manner of the Meduse. In swimming, the movements of the arms
of the Comatule exactly resemble the alternating strokes given by the
Meduse to the liquid element, and have the same effect, causing the
animal to raise itself from the bottom, and to advance, back foremost,
even more rapidly than the Medusa. Fig. 19 represents a Comatula,
after having delivered its stroke to the water.

«The evidence of Pentacrinus being the young of Comatula, rests
upon a comparison of the individuals figured,—20, 21, and 22, 23,—
the former being an advanced Pentacrinus just beginning to form
pinne, and the latter the youngest Comatula ever taken by dredging.
In the Pentacrinus, it is to be observed that the arms are just begin-
ning to form pinne towards their extremities, that they have the
sulphur-yellow color and dark marginal spotting observable in the
other, which shews, in like manner, that the upper pinne are first
formed ; here, figs. 22, 23, we have about three pairs of pinnz, with
two intervening articulations of the arm between each, then three
articuli (counting from the apex downwards), and an additional pair
of pinnee just beginning to sprout. From this to the base of the arm
are five more articuli, as yet without any pinne, the base of each arm
on either side presenting one long pinna appropriated to the service
of the mouth. On turning the animal over, the dorsal cirri are found
to have increased from five to nine, several of them presenting the
appearance of recent formation. Individuals a little older are com-
paratively common, in which the pinne are complete, and from this
period they appear to form regularly at the apex of the arm, as this
goes on extending in length. These small Comatule still retain the
siceenel sulphone paler towards the apices of the arms, the
lower part and body assuming the characteristic red of the adult
Comatula. From observations repeatedly made, I think it most pro-
bable that the Comatulee attain their full growth in one year, so as to
be in a condition to propagate their kind the summer following that
of their birth. At that time (viz., May and June,) these full grown
individuals have the membranous expansion inside each of the pinne
considerably extended, at least as far as the fifteenth or twentieth pair;
these, which are the matrices or conceptacula, at length shew them-
selves distended with the ova, which in July, and even earlier, make
their exit through a round aperture on the fascial side of each concep-
taculum, still, however, adhering together in a roundish cluster of
about a hundred each, by means of the extension and connection of
their umbilical cords. By what means these ova are dispersed, or how
they become attached to the stems and branches of corallines, remains

70 COMATULA.

to be discovered ; but it is strongly to be suspected that the animal
is gifted with the power of placing them in appropriate situations,
otherwise we should find them indiscriminately on fuci, shells, stones,
etc., which does not appear to be the case. However this may be, if
we are allowed to assume that the Pentacrinus europeus is the young
of Comatula, we first perceive the dispersed and attached ova in the
form of a flattened oval disk, by which it is permanently fixed to the
spot selected, giving exit to an obscurely-jointed stem, ending in a
elub-shaped. head, as in fig. 25, e, in which individual the animal is
sufficiently advanced to shew the incipient formation of the arms and
the mouth with its tentacula, by means of which it obtains the food

Fig. 22.

Fig. 21. Fig. 20. Fig. 23.

Figures 20 and 21. An individual of the natural size, and magnified, still more deve-
loped than 25, e, beginning to form pinnz towards the ends of the arms, as at a,b;
in this the cirri or claspers at the back of the animal are very distinctly seen.

Figures 22 and 23. A very young Comatula of the natural size, and magnified ;
Xa, the vent, in front is the star-like mouth; b, b, two of the dorsal cirri.

necessary to its successive growth. Atd of the same figure is another,
somewhat more advanced, in which all the ossicula of the arms are
obvious, as far as the bifurcation. At the letters a, b, and c, are repre-
sented what I considered formerly as completely formed Pentacrini,
(a) from the position shewing the valvular mouth, and (x) the anal
aperture : (b) shews most clearly the cirri or claspers at the top of the
stem, and (c) that the living principle extend throughout the entire
fabric demonstrated by the varied movements of the pedicle. At a
later period I observed individuals shewing a still higher degree of

COMATULA. 71

development, figure 21, and in which the arms had the appearance
of bifurcating twice towards their extreme ends, and had become
of a sulphur-yellow color, with a zone of dark colored spots along
either margin.

‘«‘ Another circumstance confirmatory of these being the young of
Comatula is derived from these Pentacrini being first seen about the
time of the dispersion of the ova of the Comatule, and again entirely
disappearing in September, the only season when young Comatule are
to be obtained, and such as are represented in figs. 22, 23. In these

co

err

RH A

Fig, 24. Fig. 25. Fig. 26.

Figure 24. Pentacrinus europeus. <A group, natural size.

“ 95, The same, magnified; jf, the basis; e and d, two individuals in early
stages of growth; a, b, c, fully developed individuals ; at +, letter a,
the anus is seen, and below it the mouth of the animal.

s¢ 96. Part of one of the arms seen in face ; a, ova protruding from the concep-
tacula; 6, ova just beginning to make their exit; c, one as yet filled
wlth the ova; d, ova magnified.

the points of resemblance to advanced Pentacrint have been already
alluded to, and it is quite evident, that since they became detached,
pinne must have been added in both directions, both towards the

72 COMATULA.

apex and downwards towards the base of the arms. These specimens
which have made a further progress are plentiful, and have all the
pinnze complete down to the bifurcation, with a few additional claspers
added at the back. At figure 19, a middle-sized Comatula decanemos
is given, as they appear in June when pregnant with ova; and at
fig. 26 is a portion of an arm magnified, with the ova beginning to
escape from the conceptacula, which they do successively from the
base upwards. Mr. Millar, in his labored but excellent work on the
Crinoidez, has figured our Comatula in this stage as a new species,
under the title of C. jimbriata; indeed, no naturalist who had not
investigated their habitudes in their own element, and at all seasons,
could possibly arrive at the knowledge of this very remarkable and
curious piece of economy, which may be considered as unique.
These animals are further distinguished by the peculiarity of having
two openings to the intestinal canal, by which they also differ from
the rest of the Asteriz.

“The great abundance of Comatule, in the places they inhabit, is
not to be wondered at when we are aware how exceedingly prolific
they are; thus each arm may be estimated to bear thirty fruitful
conceptacles, each producing about a hundred ova, and as there are
ten such, this gives 30,000! as the amount of ova produced by a
single individual.”

“#i

DECADE 4.PL1

ER ad NA GROLOCICAL SWINE OF CANADA,

(Chazy )

Horace Sinith, Del. G. Matthews. Montreal.

PLATE. I.

BLASTOIDOCRINUS CARCHARLEZEDENS (page 18).

~

Figure la-1h. Deltoid plates of B. carchariedens.

1i. Side view of aspecimen which has three of the rays partly preserved.

lk. The same, seen from above.

1l. Vertical section, shewing the position of the column in the interior.

Im. Fragment of the base, shewing the manner in which the column
penetrates into the visceral cavity.

In. Under side of 1m.

lo-ls. Small pentagonal crinoidal remains found associated with B.

carchariedens.

HYBOCRINUS PRISTINUS (page 23).

Figure 2a. Left side of a specimen which retains a portion of the column and

part of one of the arms.

PACHYOCRINUS CRASSIBASALIS (page 22).

Figure 3a. View of the base of the only specimen collected.

ce

3b. Side view of the same.

RHODOCRINUS ASPERATUS (page 27).

Figure 4a. Side view of a specimen.

ct

4b. View of the base.

4c. A radix found in the same slab along with 4a.

4d. Portion of the surface of 4c, magnified. The joints of this column
appear to be composed near the root of five pieces each, which
interlock, as represented in the figure 4d.

4e. Transverse section of the column near the root.

PALZOCRINUS STRIATUS (page 25).

Figure 5a. Posterior side of a nearly perfect specimen.

cc

5b. Summit of the same, shewing the ambulacral orifices and grooves.

DECADE 4 Pl. 2.
LOWER SILURIAN

{ Trenton)

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PLATE II.

HyYBOcCRINUS TUMIDUS (page 28),

~

Figure la. View of the anterior side of a specimen, shewing the azygos plates.
“ 4 1b-1d. Different views of other specimens.
“ 1e, A polished transverse section just below the base of the arms, shewing
the channels in the primary radial plates for the ambulacral orifices.

HyYBOCRINUS CONICUS (page 29).

Figure 2a. Right side of a specimen of the average size.
“ 9b. Left side of another specimen.

CARABOCRINUS RADIATUS (page 31).

Figure 3a. View of the anterior side, shewing the azygos inter-radius.

“ 3b. Base of the same specimen.

“ 3¢. Posterior side of a different specimen.

“ 3d. Ventral surface of a small individual. In the centre of the lower side
of the figure is the mouth, and directly above it the small anal
aperture.

‘© Ze. Ventral surface of a larger specimen, shewing obscurely the five
ambulacral grooves. The three round darkly-shaded spots appear
to be apertures accidentally produced.

CARABOCRINUS VANCORTLANDTI (page 32).

Figure 4 represents the posterior side of the specimen.

POROCRINUS CONICUS (page 34).

Figures 5a, 5b. Posterior views of two specimens.

“ 5c. Anterior side of a specimen, enlarged to shew the azygos plates and

poriferous areas.

& 5d. Ventral surface of 5a.

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PLATE Ui.

DENDROCRINUS GREGARIUS (page 36).
Posterior view of a specimen.
The left side.
Column, enlarged.
DENDROCRINUS ACUTIDACTYLUS (page 37),
Posterior side of a specimen.
Portion of the column, enlarged.

DENDROCRINUS PROBOSCIDIATUS (page 38).

Anterior side.
Part of surface of proboscis, enlarged.
Portion of column, enlarged.

DENDROCRINUS HUMILIS (page 39).

The only specimen discovered ; posterior side.

DENDROCRINUS LATIBRACHIATUS (page 39).

View of the left side, shewing the left anterior ray, which has the first
and second primary radials included in the cup,

View of the anterior side.

The posterior side.

PALZOCRINUS ANGULATUS (page 45).

Left side of the only specimen discovered.

Column, enlarged.

DENDROCRINUS RUSTICUS (page 41).
A specimen very imperfect.
A small portion of the column, enlarged.
DENDROCRINUS CYLINDRICUS (page 44).

Anterior side of D. cylindricus. That which appears to be a large
arm near the left side is the proboscis.
Part of the column, a little enlarged.

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PLATE IV.

DENDROCRINUS CONJUGANS (page 41).

Anterior side.

Column, a little enlarged.
Side view of a specimen.
Column of same, enlarged.

LECANOCRINUS LAVIS (page 47).

A slightly crushed specimen.

LECANOCRINUS ELEGANS (page 47).

A specimen shewing one of the hexagonal basal plates.
Several joints of the column, a little enlarged.

HETEROCRINUS CANADENSIS (page 48).

A specimen with part of the column attached.
Portion of the column, enlarged.

Anterior side of a different specimen.

A specimen which has the pinnule preserved.

HETEROCRINUS TENUIS (page 50).

A specimen with part of the column.
A few joints of the column, enlarged.
[ See also Plate X.]

HETEROCRINUS INEQUALIS (page 51).

A nearly perfect specimen, but so deeply embedded in stone that only
one side can be seen.

HETEROCRINUS ARTICULOSIS (page 51).

One of the rays of this species.

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GBOLOCICAL SURVEY OF CANADA.

LOWER SILURIAN

( Trenton )

G.Matthews Montreal.

Horace Smith, Del.

PLATE VF:

CLEIOCRINUS REGIUS (page 53).

Figure la. A nearly perfect cup of this species.

«16. The base, shewing the small basal plates, with the quadrangular first
primary radials between them.

“Ic, 1d, le, and 1f. Fragments of the column.
“Ig. The base of the column.

CLEIOCRINUS GRANDIS (page 54).

Figure 2a. Portions of two individuals of this species, which appear to have
grown upon the same spot.

«2b, Fragment of a column, crushed.
“« 2c. Transverse section, shewing the large alimentary canal.
[This species occurs also at Montreal, in the Trenton limestone.)

CLEIOCRINUS MAGNIFICUS (page 54).

Figure 3. Fragment of the column of this species.

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PLATE VI.

RHODOCRINUS PYRIFORMIS (page 61).

Figure la. A specimen with part of the column attached.
¢ 1b, 1c. Crushed specimens.
“1d. The radix of this species.

RHODOCRINUS MICROBASALIS (page 63).

Figure 2. An imperfect specimen of this species.

RHODOCRINUS GIGAS.

Figure 3 is a fragment of the column of a large Rhodocrinus which occurs in the
upper part of the Trenton limestone, at the City of Ottawa. I have
not seen the cup, but as the columns are easily recognizable, I propose
the above name for them.

DECADE 4 P1.7.
LOWER SILURIAN GCGiOLOGICAL SWiRVinNy Ci? CAMLAIDA,,

{ Trenton)

PLATE VII.

GLYPTOCRINUS PRISCUS (page 56).

Figure la. View of the posterior side of G. priscus.
“¢ 1b. Anterior side of the same specimen.
“1c, 1d, le, 1f. Columns found associated with la.

GLYPTOCRINUS RAMULOSUS - (page 57).

Figure 2a. A cup of medium size.
«2b. Portion of the column near the base of the cup.
‘« 2c-2f, These figures represent different parts of a very long column.
' [See also Plate VIII. ]

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Horace Smitb.Del.

PLATE VIII.

GLYPTOCRINUS RAMULOSUS (page 57).

Figure la. A crushed specimen, with part of the column attached.
¢ 1b. The column of 1a, enlarged.
«le, 1d. Columns found along with 1a.
““ le. A portion of one of the arms, enlarged.
[ See also Plate VII. ]

GLYPTOCRINUS LACUNOSUS (page 61).

Figure 3a. A specimen with part of the column attached.
“3b. Fragment of a different specimen.

«¢ 8c, 3d, 3e. Columns of this species.

GLYPTOCRINUS QUINQUEPARTITUS.

Figure 4a-4b. Columns such as the specimen represented by these figures are not
uncommon in the upper part of the Trenton limestone, at the
City of Ottawa.

DECADE 4.P1.9.
LOWER SILURIAN

Ol? CANADA.

£

D

CUOLOGICAL S

( Trenton)

G. Matthews. Montreal.

Horace Smith.Del.

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PLATE IX.

GLYPTOCRINUS MARGINATUS (page 59).

The only specimen collected. The part well exposed (represented in
the right side of the figure) is the azygos inter-radius.

GLYPTOCRINUS ORNATUS (page 60).

Anterior side of a specimen of G. ornatus.

RETEOCRINUS FIMBRIATUS (page 65).

The only specimen discovered.

The base, enlarged; the unshaded pentagonal space shews the form of
the upper joint of the column.

One of the arms, with some of the pinnule attached, enlarged.

RETEOCRINUS STELLARIS (page 64).

View of the anterior side of a specimen.

A specimen retaining a piece of the column.

Several of the joints enlarged. They appear to be nearly equal in size,
and sharp-edged at the base of the cup.

“4d, 4e. Fragments of this species.

[ In 4a and 4e the small stellate plates between the arms are represented. ]

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PLATE X.

HETEROCRINUS TENUIS (page 50).

Heterocrinus tenuis, from the Trenton limestone, near the City of
Montreal.
Part of column and base of another specimen on same slab.

Enlargement of 1b.

‘© 1d, le. Other fragments on the same slab of stone.

Figure 2a.

OB PD.
MS eee
Figure 14.

Figure 3.

4-7,

ae vLO),
se lulu
oi |e
ald

[ See also Plate IV.]

CARABOCRINUS TUBERCULATUS (page 33).

The only specimen collected.
Three joints of the column, enlarged.
One of the joints of the arms, enlarged.

SYRINGOCRINUS PARADOXICUS (page 65).

A specimen collected at Beauport.

COLUMNS OF UNDETERMINED GENUS.

A quinquepartite column from the Trenton limestone, City of Ottawa.
Fragments from Hudson River group, Point William, Lake Huron.

From Trenton limestone, Montreal.

The same, enlarged.

From the Hudson River group, Anticosti.

The same, enlarged.

A small striated column from the Trenton limestone, City of Montreal.

The same, enlarged.

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FIGURES AND DESCRIPTIONS OF cal bee
ORGANIC REMAINS. |

| | paca 1.--FOSSILS from the base of the Trenton Group. By. J. wes AL

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« IL—GRAPTOLITIDEE from the Lower -sitsian, By fessor Ja

months.

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S ‘Boronta ; ‘JOHN v WILEY, New York; “HECTOR : BOSSANGE

55