Rodolfo Amedeo Lanciani.

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embryonic stages of those of the same class at present existing.
Prof Agassiz has long taught in his lectures and various pub-
lications, that this is especially observable in the Echinodermata.
Judging from the figures and descriptions of Miiller, Agaasiz,
Thomson, Carpenter and others, I should say, that in this class,
the most strikmg resemblance is that which occurs between the
adult stages of the Cystidea, Blastoidea, and Orinoidea, on the
one hand, and the embryonic Star-fishes on the other. The
structural character that has the most important bearing on the
subjects discussed in these notes, is, that in all four of these
groups, the mouth is situated in one of the interradial areas, —
not in the ambulacral center, as it is in the adult forms of the
existing Echinodermata.

In Bipinaria asierigera Sars, according to MtQler, the digestive
cavity is a sub-globular sack without any extensions into the
rays, as there are in the adult Star-fishe& The oesophagus, fig.
8, 0, is a fieshy, consistent tube, with a large mouth or psendos-
tome, p. It passes through the wall of the stomach by an open-
ing somewhat smaller than the mouth, and situated in one
of the interradial spaces at m. The madreporic plate, f and
sand canal, 6, the latter holding the convoluted plate (when it

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E. BUUngs on the structure of Orinaidea^ OystOea^ etc 23S

occurs), are situated above the orifice, m, and between it and the
ambulacral center, c. The circular space at c, is undoubtedly
the homologue of the central space in the apex of Nucleocrtnvs,
fig& 3 and 5, and of Codonites, figs. 10 and 11. It is also the
position of the mouth in the adult Star-fish ; but in the larval
stage it is completely closed by the soft external skin and sar-
code of the body. In the fossils it is also closed, but by an
internment of thin calcareous platea The Mpinnaria is
nourished by minute particles of matter diffused flirough the
water, and drawn into the digestive sack through the mouth
and oesophagus by the action of interradial cilia. I believe
that aU the fossil Crinoidea, Blastoidea and Cystidea, ingested
their food in this way, and without any aid whatever firom the
arms or pinnulae.

Perhaps there is no embryologist who will not admit, that it
is possible for an animal like Bipinnaria to develope organs of
reproduction and propagate its roecies, none of its other parts
making any iGarther advance. Such an animal, with some
slight modincations, would hot be very widely different fix)m a
paleozoic Crinoid. K the sarcodic iJody wall wotc to be con-
solidated into a thin calcareous integument, with the mouth
even with the surface, the swimminff appendages aborted, and
the vent closed up, it would resemble tne cup of an Admocri-
nusj fig. 9, a. The lateral orifice would then be both mouth
and vent, as it is, at first (according to Prof A. Agassiz, Seaside
Studies, p. 125), in the embryo of Asteracanthton Berylinua.
The ambulacral canals of Bipmnaria are the homologues, in
a general way, of those which are found beneath the vault of
Aetinocrinvs^ and extend out into the grooves of the arms. If
the ventral perisome of the Crinoid were to be removed (the
internal oigans remaining undisturbed) the arrangement dis-
closed womd be that represented in fie. 9, — a convoluted plate
in the center with the canals radiating firom it The most strik-
ing difference is the absence of the oesophageal ring. Accord-
ing to the organiisation of Actiiu>cTiniA8 there could be no
oesphagus at that point, and consequently there is no ring. The
convoluted plate represents the madreporic apparatus. The
sucking feet of the Star-fish, most probably, represent the re-
spiratory tentacles that border the grooves of the Crinoids, but
modifiea into prehensile and locomotive organs. Bipinnaria
and Actinocrinue agree in having the mouth in Que of me inter-
radial areas, and in the absence of an orifice through the
perisome at the ambulacral center. These two characters are
embryonic and transitory in the Star-fish, but they were perma-
nent m most paleozoic Orinoids.

In Oodonites steUi/ormis {Pentremites steU^brmia Owen and
Shumard), figs. 10, 11, the ambidacral center, c, is completely

Am. Joub. Sol—Sbookd Sxbibs, Vol. L, No. 149.— Sxpt., ISTOl

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234 E, BtUings on the structure of Crinoidea^ Oystidea, etc

closed. Five minute grooves radiate out to the extremities of
the five angles of the disc. These grooves are identical with
those of Pentremites and Nucleocrinus and were occupied by
the ovarian tubea The ambulacral canals of the true CrinoidB
and of the Star-fishes are represented in a rudimentary condi-
tion, in this species, by the hydrospires which open out to the
surfece through the ten fissure-like spiracles, s. The oro-anal
orifice is inteiradiaL C stelU/ormis in external form, the inter-
radial position of the mouth, and the closed ambulacral center,
resembles Bipinnaria and J.cfo*nocrmt^5, but differs importantly in
having its respiratory organs arranged in ten separate tracts, all
totally disconnected fix)m each other. It is a lower form than
Actinocrinusj which in its turn is lower than Bipinnaria^ and
yet all three are constructed on the same general plan.

C. sielliformis^ although much resembling a Pentremite, is a
true Cystidean. Its affinity to Oodaste)' was first pointed out
by Dr. C. A. White, who also suggested that it should be as-
signed to a distinct group. (Bost Jour. N. H., voL vii, pp.
486, 487). The main difference between the Cystidea and flie
Blastoidea is, that in the former the hydrospires do not com-
municate with the pinnulsB, whilst in the latter the cavities
of the pinnulfiB and hydrospires are directly connected by the
ambulacral pores.

The developement of the recent Crinoid Antedon rosaceus,
as described by Prof Wyville Thomson (Phil. Trana, 1866),
pursues a course that could not possibly result in the produc-
tion of such an animal as Actinocrinus. The pseudembiyo, as
it is called by Prof Thomson, is a small ovate organism, with
four transverse ciliated bands, a large key-hole-shaped mout^
(pseudostome), and a small circular vent (pseudoproct). These
orifices are connected by a rudimentary mtestine (pseudoeele).
In this stage there is no trace of radiation, and the moutJi,
therefore, cannot be said to be interradial in its position.

The nascent Crinoid originates within the pseudembryo, but
developes a mouth, vent and stomach, of its own, all quite dis-
tinct fpom those of its nurse. This new, or permanent mouth,
is for a short time both oral and anal in its function, but al-
though in this respect it resembles that of ActinocrinvSj its po-
sition in the center of the ambidacral system, shows it to
represent the mouth of the adult Star-fish, while that oiActinO'
cnmis rather homologates with the oral orifice of the Bipin-
narioL At no* time during its development does the ventral
perisome exhibit the structure of that of the paleocrinoids,
L e., no orifice in the ambulacral center, and at tne same time
one in an interradial spaca In the central position of its mouth,
and in the possession of an oesophageal ring, Antedon stands

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E, BiUings on the structure of Orinoidea, Ch/stideOj etc 235

above Actinocrtnus in rank, and between it and the adult Star-
fish. In none of its stages does it resemble a Bipinnaria either
in form or in structure.

9. On some of the objections that have been advanced against the
views advocated in the preceding notes.

In all the known species of the existing Echinodermata, the
mouth is situated in the center of the ambulacral system, and
it is contended that this fact proves that such must have been
its position also in the paleozoic forms.

This reasoning is not strictly logicaL It is true that in the
known existing species, the moutn is in the center, but it
does not certainly follow that it is so in all the Echinodermata,
living and extinct Whether it be so or not in any particu-
lar fossil species whose structure may be under investigation,
is a question of fact which can only he positively determined by
direct observation of specimens. On appealing to these we find
that, in a large proportion of the fossil forms, there is no aper-
ture in the perisome at the ambulacral center. It also becomes
evident by the comparison that, in general, the paleozoic spe-
cies resemble the embryonic stages of some of the recent
Echinoderms, and that in these, pBipinnaria for instance), the
mouth is interradiaL Rules such as is relied on in this case,
afford a certain amount of presumptive evidence, which, how-
ever, cannot prevail against material and visible facts. When
we can see clearly that there is no aperture in that point, in
the vault of a Crinoid, beneath which we know the ambulacral
center is situated, it is perfectly useless to supply one by de-

The second objection is, that many of the fossils have a
Platycera^ attached to them, in such a position as to cover the
aperture which I call the mouth, and under such circumstances
as to induce the belief that it lived parasitically on the Crinoid.
The only answer I can make to this is that, admitting the facts,
we must suppose that space was left for a stream of water to
pass under the edge of the shell, into the mouth of the Crinoid.
In general, where one animal lives parasitically upon another,
it does not destroy its host Some of the gasteropods of the
Devonian and Carboniferous ages, were carnivorous, as is

})roved by the bored shells and Crinoids that are occasionally
bund. I have seen a number of such specimens, and several

* The position of the ambulacral center maj thus be found. When the mouth
18 eccentric, the ambulacral tubes usuallj converge to the center of the yault
But when the mouth is central, we first find the azygos interradius, in general
easily recognized bj its possessing a greater number of plates tlian do anj one of
the other four interradii. On the opposite side of the fossil is the azygos arm.
The ambulacral center is always .<«ituated between this arm and the moutih, never
on the side of the mouth toward theasygos interradius.

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286 E, BiUings on the structure of Orinoidea^ CysiidecL, etc

years ago I read a paper on the subject (which was neverpub-
lished) before the K^atural History Society of Montreal. T^ere
were several good Oonchologists present, and the specimens ex-
hibited were compared with bored shells of existing species.
All pronounced the sty^le of workmanship to be precisely the
same. I have the proboscis of an Actinocrinus that is bored

near the base, and among the

fossils lent me b^ Mr. Wach-

smuth, is a Codonttes stelliformis^

that is bored through one of the

ambulacra. The view I took of

the subject in my paper, was

that the gasteropod ascended the

Fto. u. 8trmtorhvnchu9 Pandora, A Stalk of the Cnuoid, and thrust

'^^^"i^v^yo^lSi^^^ZSS^, its proboscis mto the mouth of

56Yonian.c«uMiE. ^hc latter. The Crinoid then

slowly drew its arm together, and held the shell feat until

both died.

A third objection is the small size of the aperture in some
of the species. In general, where there is no proboscis, the ori-
fice is from one-twentieth to one-tenth of an mch in diameter,
quite sufficient for an animal that subsists on microscopic
organisms. It is stated by Meek and Worthen that where
there is a proboscis, the aperture is sometimes scarcely " more
than one-hundredth of an mch in diameter." I believe that in
many such instances the tube filled up by calcareous deposits
on its inside, and that when entirely obstructed, either a new
aperture opened out in the side of the proboscis, or that the
animal died. In Mr. Wachsmuth's collection, I saw a ^eci-
men with a second aperture in process of formation. A ticket
was attached to it by him, giving this explanation. I am also
informed that in some of the existing species of Antedon *' the
mouth is an exceedingly minute apertura"

A fourth objection is that the aperture is so situated that
the arms could not have conveyed food to it It is, however,
proved by Dr. W. B. Carpenter, that in the recent Crinoids
the arms are not prehensile organs. The animal while feeding
remains motionless, attached oy its dorsal cirrhi to a stone,
shell, or other object on the bottom. Its arms are either
stretched out to their full length, or more or less coiled up, but
(juite immovable. As Dr. Carpenter's remarks have a very
important bearing upon the subject, I shall take the liberty of
quoting the following : —

"Whatever may be the purpose of the habitual expansion
of the arms, I feel quite justified that it is not (as stated oy sev-
eral authors whom I have cited in my historical summary) the
prehension of food. I have continually watched the results of

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E. Billings on the structure of Orinaidea^ Oystidea, etc 287

the contact of small animals (as Annelids, or Entomostracans
and other small Crastaceans) with the arms, and have never yet
seen the smallest attempt on the part of the animal to seize
tliem as prey. Moreover, the tubalar tentacula with which the
arms are so abundantly furnished, have not in the slightest de-
gree that adhesive power which is possessed by the " feet " of
the EcHiNiDBA and Astesiada ; so that they are quite incapable
of assisting in the act of prehension, which must be accomplished,
if at all, either by the coiling-up of a single arm, or by the
folding-together of all the arms. Now I have never seen such
coiling up of an arm as could bring an object that might be in-
cluded in it into the near neighborhood of the mouth ; nor have
I seen the contact of small animals with a single arm produce
any movement of other arms towards the spot, such as takes
place in the prehensile apparatus of other animals. Moreover,
any object that could be grasped either by the coiling of one
arm, or by the consentaneous closure of all the arms together
upon it, must be fiar too large to be received into the mouth, which
is of small size and not distensible like that of the Astbboida."*

Farther on Dr. Carpenter says :

"It was affirmed by M. Dnjardin (I'Institut, No. 119, p. 268)
that the arms are used for the acquisition of food in a manner
altogether dissimilar to ordinary prehension ; for recognizing the
fact that the alimentary particles must be of small size, he suppo-
sed that any such, fallmg on the ambulacral (?) furrows of the
arms or pinnae, are transmitted downwards along those furrows to
the mouth wherein they all terminate, by the mechanical action of
the digitate papillsB which fringe their borders. This doctrineJie
atmears to have abandoned; since in his last account of this ty}»e
(mst. Nat. des Echinoderms, p. 194) he affirms that the trans-
mission of alimentary particles along the ambulacral (?) furrows
is the result of the action of cilia with which their surface is clot-
ted. Although I have not myself succeeded in distinguishing cilia
on the surface which forms the floor of these furrows, yet 1 have
distinctly seen such a rapid passage of minute particles along
their groove as I could not account for in any otner mode, and
am therefore disposed to believe in their existence. Such a power-
fid indraught^ moreover^ must be produced about the region of the
mouthy by the action of the large cilia which (as I shall hereafter
describe) fringe various parts of the internal wall of the alimentary
canalf as wofdd materially aiain the transmission of minute par-
ticles along th4>se portions of the ambulacral (?) furrows which inv-
mediately lead toward it ; and it is, I feel satisfied, by the con-
joint agency of these two moving powers that the alimentation of
Antedon is ordinarily affected. In the very numerous specimens
from Arran the contents of whose digestive cavity I have exam-
ined, I have never found any other than microscopic organisms ;

* Researohe^ on the Structnre. Physiology, and Development of Aniedtm {Oom'
oMoy Lamk.) ro^ocetM.— Part I. Bj W. B. Carpenter, M.D., F.R.S. Philosophical
Transactions of the Eojal Society, vol. dvi, Part 11. 1866

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288 E. Billings on the structure of Orinoidea, Oystidea^ etc

and the abundance of the homy rays Peridinium tripos (£hr.)
has made it evident that in this locahty that Infasorium was one
of the principal articles of its food. But in Antedons from other
localities, I have found a more miscellaneous assemblage of ali-
mentary particles ; the most common recognizable forms being the
homy casings of Entomostbaca or of the larv8B of higher Crus-
tacea." (Op. cit, p. 700).

The existence of large cilia within the intestinal canal, capa-
ble of producing a powerful indraught of water, renders any
movement or concurrent action of the arms quite unnecessary
in the ingestion ^f food. It does not matter, therefore, in what

Eart of the body the mouth of a Orinoid may be situated, or
ow remote from the reach of the arms. Attached permanently
to the bottom of the sea by their columns, the paleozoic Cn-
noidea, Cystidea and Blastoidea remained, while feeding, most
probably motionless, drawing in streams of water through their
mouths by the action of their intestinal cilia. The long tubu-
lar proboscis, with which many of the species are provided,
would be, thus, analogous in function to the siphon of the
acephalous mollusca. The indigestible particles would be,
from time to time, thrown out through the mouth, just as a
Star-fish or a Zoophyte frees itself of the refuse portions of its
food, by casting it out of the same aperture through which it

10. On the Theory that ffie ambulacra! and ovarian orifices are
ffie oral apertures.

Assuming that the four objections above noticed are suffi-
cient to prove that the aperture which I call the mouth is not
that organ, it is contended that the Cystidea, Blastoidea and
Palaeocrinidea ingested their food through their ambulacral and
ovarian orifices. This appears to me in the highest degree im-
probable In the recent Crinoids the grooves of the arms are
occupied by four sets of tubes, which Dr. Carpenter calls the
coeliac, the sub-tentacular, the ovarian and the tentacular canals.
None of them communicate with the stomach. It is impossi-
ble that the most minute particle of food could gain access into
the interior of the animal through any of them. The struc-
ture of the arms of the paleozoic Cnnoids is such, that we
must presume that their grooves were occupied by similar
tubes, which passed through the ambulacral orifices into the
perivisceral space. In the Cystidea and Blastoidea the respira-
tory organs were not situated in the grooves of the arms, and
the ambulacral orifices were therefore only ovarian in their
function. The improbability of iheir being also oral aper-
tures is best shown by an illustration.

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E. Billings on the structure of OrinoideOj Oystidea^ etc. 289

In fig. 18, is represented (natural size) the apertures of the

13. 14. smallest specimen of Caryocrinxis ornatus)

•— \ y'T^ in ^1^ collection, selected for the present

I \ L o purpose because in the young of this spe-

V ® J V.® y ^^^ the valvular orifice is larger in pro-

^^ y ^ — 'y portion to the size of the disc, than it is in

the adult It is in this specimen, about
one-third of the whole width of the apical disc, while in a full
grown Garyocrinvs it is only one-ninth of the widtL The
same proportional size of the mouth according to age, occurs in
Antedon rosaceus. The valvular mouth at first is as wide as
the disc. But as the age of the animal increases the disc grows
wider but the mouth does not Th6 ovarian pores in Caryocru
nus are, however, as large in the small ones (once they make
their appearance) as they are in those fiill grown. For recog-
nizing tnese as ovarian pores we have the following reasons : —

1. They are situated at the bases of the arms where the ovarian
tubes must pass fix>m the grooves into the perivisceral cavity.

2. When compared with the ovarian pores of a Sea-urchin they
have the same size, form and aspect Fig. 14, represents the
ovarian pores of the Sea-urchin Toxopnetistes Drobachiensis Ag.
natural size and arrangement It may not appear at first view
that this latter comparison has any probative enect But it has,
in this way. If these apertures in Caryocrinvs were large open-
ing a line wide, as are some of the ambulacral orifices of the
Crmoids, I would say that they were unlike true ovarian apertures.

According to the new theorv, this Echinoderm Caryocrinvs
omatus was a polystome animal^ and drew in its food through
its six ovarian apertures, the large valvular orifice being tne
anus. To me this appears to be utterly incredibla

In fig. 14 I have represented the mouth of Leahia mirabilis
Gray. Both Dr. I. E. Gray and Prof Lovdn have pronounced
this aperture to have the structure of the valvular orifice of the
Cystidea. I have not the slightest doubt whatever but that the
mouth of the Oystideans foreshadows that of the Sea-urchins.
There is nothing whatever in its structure to show that it is not
the mouth but on the contrary.

The new theory is not founded upon any peculiarities in the
structure of the ambulacral orifices, which would show that
they are oral apertures, but only upon the four objections
above noticed. The first of these is not logical, while at the
same time it is purely theoretical, and avails nothing against
material and visiole facts. The fourth is completelv disposed
of by Dr. Carpenter's observations, which prove that in the
Crinoidea the arms have no share whatever in the ingestion of
food. The second and third objections are the same in sub-
stance, i e., according to the second the supply of water to the

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240 W. O. Leisan — Predjntatian and D^ermincUton

mouth, is diminished by the occurence of a Platycerus over it,
while, according to the third, the same effect is produced by
the small size of the aperture itself in some instances. It does
not require much consideration to convince one, that if these
two objections are fatal to my views, they are equally so to the
opposite theory. In C. stelli/ormis, for instance, the pores
through which we must suppose the ovarian tubes issued from
the interior are only large enough to -fidmit of the passage of a
fine hair. They are scarcely visible to the nakea eye. The
tube, under any circumstances, must have filled them almost
entirely. If any space at all were left for the passage of a
stream of water thix)ugh the pore by the side of the tube it
must have been exceedingly minute.

When weighed as above, therefore, the evidence gives the
following results : — The first and fourth objections avail noth-
ing. The second and third militate against both theories. But
when we take into account that in no instance, in the existing
Echinodermata, where ovarian pores occur, are they at the same
time oral orifices, the balance seems to be in &vor of my view.
This is all I desire to say upon the subject at present Although
I now firmly believe that the valvtdar orifice in the Cystidea,
the larger lateral aperture of the Blastoidea, and the so-called
proboscis of the paleozoic Crinoids are all oro-anal in function,
yet I shall not maintain that view obstinately against good
reason shown to the contrary.

Art. XXrV*. — Contnbutions to Chemistry from ike Laboratory of
the Lawrence Scientific School No. 12.

On the precipitation ami determination of the metals of the magne-
sium group in the form of oxalates; by W. GouLD Leison.

Prof. Gibbs has recently* called attention to the feet that a
number of metallic oxyds may be completelj^ precipitated from
their neutral solutions by means of oxalic acid, provided that a
large excess of alcohol be also added. As it is not easy to
obtain precise quantitative results by igniting the oxalates so
precipitated, in consequence of the extreme subdivision of
the resulting oxyds, Prof Gibbs suggested the employment of
potassic hypermanganate for the coinbustion of the oxalic acid,
a method which — ^as is well known — ffives excellent results in
the case of calcic oxalate precipitated in the ordinary manner.
The following investigation was undertaken for the purpose of
testing this method of analysis : —

* This Journal, zliy, p. 213.

Digitized by VjOOQ IC

of the Mekds of ihe M(igne8ium Oroup. 241

Cadmium. — Cadmic sulpliate was dissolved in tlie least possi-
ble quantity of water, oxalic acid added iu excess, and tnen a

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