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3. That a man ought not to pray with the uuregener-
ate, even though it be with his wife or child.



84 BULLETIN OF THE ESSEX INSTITUTE.

4. That a man ought not to give thanks after the
sacrament nor after meat.

Earnest debate followed, and he was dismissed till the
next General Court, which was to meet at Newtown, " to
consider these thiugs."

In October he was summoned asrain for the last time.
His opinions had not changed. The Court, instructed by
the ministers, decided that he should depart out of their
jurisdiction within six weeks. The following is the act
of banishment as it stands upon the colony records :
" Whereas, Mr. Roger Williams, one of the elders of the
church of Salem, hath broached and divulged divers new
and dangerous opinions against the authority of magis-
trates ; as also writ letters of defamation, both of the
magistrates and churches here, and that before any con-
viction, and yet maintaineth the same without any retrac-
tion ; it is therefore ordered, that the said Mr. Williams
shall depart out of this jurisdiction within six weeks now
next ensuing, which if he neglect to perform, it shall
be lawful for the Governor and two of the magistrates
to send him to some place out of this jurisdiction, not to
return any more without license from the Court."

This act of banishment was passed on the 3d of Nov.,
all the ministers save one approving it.

The Rev. Dr. Dexter, who has written an elaborate and
very interesting book to prove, or to endeavor to prove,
" the very great wrong done to the memory of the Puri-
tans of Massachusetts" in the case of Roger Williams,
gives us a very graphic picture of this " Particular " Court.
After mentioning by name the deputies who were prob-
ably present, among whom we find many of our old
friends of the past summer (the Salem men conspicuous
by their absence), he refers to the ministers of the Bay,



ROGER WILLIAMS IN SALEM. 85

fifteen in num])er, twelve of whom were certainly there,
nine of them were graduates of Cambridge, and nine of
them had held rectorships in the " fatherland." He closes
with the followins: words: "Altonjether it was a distin-
guished company ; and it may well be doubted whether
the Massachusetts of to-day, even under the classic shades
of that great university which marks the spot where this
Court was held, now almost as well known to the learned
world as is that ancient shrine of knowledge whose schol-
astic robes so many of them were entitled to wear, could
call together out of its hundreds of pulpits twelve pastors
and teachers who should be their equals in intellect and
worth, and in all those imperial qualities which fit men to
be the founders of states."

In Salem the whole community was in an uproar. The
time had been extended till spring, but his presence was
soon considered dangerous, many of the people resorting
to his house to listen to his teachings ; the fathers of the
colony therefore determined to send him to England.
They sent for him to come to Boston but he refused (m
account of ill health. Nothing daunted they sent a small
sloop to Salem with a warrant to Captain Underhill to
apprehend him and carry him on board a ship which was
to sail immediately for England. When, however, the offi-
cers went to his house they found he had gone three days
before. It was in January, 1636, that Roger Williams left
his home in Salem (still standing) for the wilderness;
thirty-five years afterwards he says in a letter, " I was
sorely tossed for fourteen weeks in a bitter winter season,
not knowing what bread or bed did mean."

Here closes the Salem life of Roger Williams. Never
again, in the fifty-odd years more of his busy, useful life
was he allowed to visit the peo])le whom he loved so
well ; once only vi^as he allowed to land in Boston on his



86 BULLETIN OF THE ESSEX INSTITUTE.

return from England, and then only at the intercession of
powerful English friends, several noblemen and other
members of Parliament.

As his life in Rhode Island has but little to do with our
local history, I shall not follow him there, contenting
myself with saying that our little sister State may well be
proud of its noble founder.



THE CHONDROCRANIUM IN THE
ICHTHYOPSIDA.i



BY GUY MONROE WINSLOW.



CONTENTS.



PAGE

Introduction, 87

Amblystoma, 90

Desmoguathus, 99

Plethodon, 100

Necturus, 101

Amphiuraa, 104

The Chondrocraniiim in tlie Urodela, 108

Pipa, 110

Contrasts between Urodela and Anura, 112

Ichtliyopliis, 115

The Chondrocranium in the Csecilia, 120

Polypterus, 122

Trout. 124

The Chondrocranium in the Fishes, 126

Protopterus, 128

The Chondrocranium in the Dipnoi, 131

Literature, 134

Explanation of Figures, 138

» Studies from the Biological Laboratorj' of Tufts College, under the direction
of .1. S. Kingsley, No. xix.

I wish here to give credit for some of the material used in these studies.
The Necturus larvce were given to me by Miss Julia B. Piatt; for Pipa I am
Indebted to the late Professor E. D. Cope; Professor Robert Wiedersheim fur-
nished me witli the Protopterus material and I began the study of the chon-
drocranium of this Dipnoan in his laboratory. For Amphiuma I am indebted
to Professor O. P. Hay, the first to find embryos of this interesting Urodele,
and to the late Professor .lohn A. Ryder, who kindly turned over to me the
embryos sent him by Doctor Souchon of New Orleans. The embryo Cxcilians
were given me by the cousins Paul and Fritz Sarasin and were a part of the
material which formed the basis of their splendid monograph. To all these I
return my best thanks.

J.S. KiNOSLKY.

(87)



88 BULLETIN OF THE ESSEX INSTITUTE.



INTRODUCTION.

The work, the results of which are given in the follow-
ing pages, has been carried on in the Biological Laboratory
of Tufts College, under the direction of Dr. J. S. Kings-
ley, to Avhom the author is deeply indebted, not only for
the use of much of the material studied, a considerable
part of which was already prepared, but far more for in-
valuable aid and encouragement during the preparation of
this paper. It is also due to Dr. Kingsley to acknowl-
edge the free access to his private library containing a
large portion of the literature upon the subject, and to
state that the models of the first stage of Amphiuma and
the three stages of Necturas were made by him.

In my account of the development of the chondrocra-
nium I have not attempted to treat of the origin of the
pro -cartilage cells, but I begin with the first formation of
cartilage. These earlier stages have been so ably de-
scribed by Miss Piatt ('93, '94) that there seems no ne-
cessity to repeat her account, especially as her discoveries
in regard to the ectodermal orio;in of the cartilage-form-
ing cells were largely made in this laboratory, and have
received general support and confirmation in the papers
of Kastschenko ('88), Goronowitsch ('92, '93, '93^),
Klaatsch ('94, '95) and von Kupffer ('95).

One object in these investigations was to ascertain to
what extent the primary cranial structures throw light
upon some problems in the classification of certain Ichthy-
opsida. The principal of these problems were these :

(1) By most students the Caecilians have been recog-
nized as a distinct order of Batrachia, but more recently
the late Professor Cope in several papers has maintained
that these forms were in reality aberrant Urodeles and



THE CHONDROCRANIUM IN THE ICHTHYOPSIDA. 89

should have only family rank in that order. Summariz-
ing his conclusions, he maintained that the Cfficilians were
descended from Amphiuma-iike forms and these in turn
were oflfshoots from some amblystomoid Urodele. The
cousins Sarasin, while agreeing with Professor Cope in
the view that the Cfficilians and Amphinma were nearly
related, regarded the relationship as differing in this re-
spect. Amphiuma was a neotenic Crecilian, a larval Cae-
cilian become sexually mature. My problem was to
ascertain in how far the chondrocranial structures gave
support to any of these views.

(2) The fact that the Dipnoi possess lungs led to
the view, which has obtained wide acceptance, that these
ancient fish-like forms were the ancestors of the Batra-
chia, and this view has received no little support from
Huxley's short but most suggestive discussion of the sus-
pensorial apparatus in the Ichthyopsida. More recently
several students have maintained that the Batrachia have
sprung from the Crossopterygian Ganoids and that the
only relationship that can be traced between Dipnoi and
Amphibians is that the lung-fishes may have had the same
ancestr}'', but that they can in no wise be considered as in
the line of batrachian descent. In how far does the chon-
drocranium support either of these views?

It has not been my purpose to enter the broader field of
the relationships of these different groups as is shown by
other features. I have confined myself closely to the
chondrocranium and my results are to be regarded as
merely one factor in deciding these questions ; a factor in
itself of minor importance.

I take as the basis of my studies the development of
the chondrocranium of Ambhj stoma punctata^ since of this
form I have had the most abundant material. This is
followed by an account of certain stages of the chondro-

KS8EX INST. BULLETIN, VOL. XXVIII 6*



90 BULLETIN OF THE ESSEX INSTITUTE.

crania of some other Ichthyopsida, and an attempt is made
to see how far the chondrocranium can be employed as an
aid in the classification of these forms.

The various stages are determined in an arbitrary man-
ner by body length, but it is to be borne in mind that there
is considerable variation in embryos and larvae of the same
size. All stages described have been modelled in wax by
Born's method, the models have afterwards been care-
fully measured and compared and all exaggerations of
proportion due to slight variiitions in the thickness of the
wax have been corrected in the drawings.

Ambltstoma punctata.

First stage. — Embryo ten mm. long. Mouth on the
point of breaking through (Figs. 1 and 2). This stage,
which I have taken as the starting point of my investi-
gations, corresponds closely with that at which Ph. Stohr
begins his classic account of the chondrocrania of Triton
and the Axolotl ('79). The chondrocraiiial elements are
still in the pro-cartilage condition but they are clearly
difierentiated from the surrounding parts by the arrange-
ment of their cells. Three pairs of elements are present,
namely, the parachordals, trabeculae and the quadrates.

The parachordals (v) lie as two triangular plates upon
each side of the slightly depressed anterior end of the
notochord. One side of each triangular plate is directed
anteriorly and the antero-exterior angle joins the poste-
rior end of the trabecula, Avhile the inner face of each
abuts against the side of the notochord (n). The lateral
margin of the parachordal runs obliquely outwards and
forwards from its posterior angle to the junction with the
trabecula. The parachordals arise separately and at this
stage touch only at the sides of the notochord, thus leav-



THE CHONDROCRANIUM IN THE ICHTHYOPSIDA. 91

ing the upper and under surfaces and the tip of the latter
exposed.

The trabeculse {t) continue forwards in neaa-ly the same
horizontal plane as the main part of the notochord, the
apex of which, with the adjoining portions of the para-
chordals, is slightly depressed. The trabeculoe curve first
outwards to a point beyond their middle and then in, their
apices being about as far apart as their bases. They end
medially to the olfactory organs, a little behind the exter-
nal narial openings. The lower margin of each trabec-
ula is thickened, while above it is developed into a high
and thinner crest {trc) inclining slightly outwards. The
upper margin of this crest is extremely irregular and the
foramina for the optic and oculomotor nerves (o/" and oc)
are but partially enclosed. The crest gradually increases
in height from in front Ijackwards to the posterior end of
the trabecula where it terminates abruptly.

The quadrates appear as two thin bands of cartilage
external to and at some distance from the parachordals.
They are concave anteriorly and their general direction is
downwards and outwards. In each quadrate can be al-
ready recognized three portions, a middle piece constitut-
ing a body (hq) from which arise an upper ascending
process {op) directed forward, inward and upward toward
the crest of the trabecula, and a lower descending process
{dp) ruiming outward, forward and downward to the
articulation with Meckel's cartilage. The body is some-
what lenticular while the processes are thin and more
laminate.

Meckel's cartilage {ra) is already complete. The gen-
eral course of each ramus is obliquely inward and for-
ward until about the middle point where it curves 'still
more strongly inward to meet its fellow of the oi)posite
bide. At its base each ramus is stout but it tapers regu-



92 BULLETIN OF THE ESSEX INSTITUTE.

larly and is slender at the point of union. A point which
seems to me of considerable morphological importance is
that the symphysis is considerably behind the apices of
the trabecule, recalling in this embryonic stage the con-
ditions which are permanent in the Elasmobranchs and
lower Ganoids.

Second STAGE. — Embryo, eleven mm. long (Fig. 3).
The parts described in the first stage have chondrified
rapidly and two new pairs of cranial elements, the otic
capsules and the two processes of the occipital arch, have
made their appearance.

The occipital arch {ocp) is composed of two isolated
conical pieces of cartilage, the bases of which rest upon
the sides of the notochord a little behind the otic region.
From the notochord they curve outwards and upwards, half
encircling the medulla and terminating freely. The in-
completely developed otic capsules (o) are represented by
thin layers of cartilage, very irregular in outline, cover-
ing the lateral and portions of the dorsal and ventral sur-
faces of the auditory vesicles. Their anterior ends lie
immediately behind and above the bodies of the quad-
rates while their posterior ends are somewhat nearer the
median line, just in front of the occipital arch. The ven-
tral walls of the two capsules are in nearly the same hor-
izontal plane with the notochord and the parachordals.
There are no cartilaginous connections between the cap-
sules and the rest of the chondrocranium.

The parachordals (j?) have fused with each other at the
apex of the notochord and now extend back along its sides
to about the middle of the otic region where each gives
off a lateral process which underlies the median portion of
the sacculus. Although the median wall of the otic cap-
sule is as yet but slightly developed, its future lino of
fusion with the parachordal is clearly indicated by a lon-
gitudinal marginal thickening of the latter.



THE CHONDROCRANIDM IN THE ICHTHYOPSIDA. 93

Accompanying the general growth of the head and the
lessening of the cranial flexure, the trabeculte {t) have in-
creased considerably in size, more especially in length.
At their anterior ends they have become slightly broad-
ened and flattened to form the cornua trabeculae (c), the
first indications of the nasal capsules. The gaps between
the disconnected portions of the trabecular crest of the
first stage are now filled, forming a plate, the dorsal mar-
gin of which is a smooth, undulating line sloping gradu-
ually downward in passing from behind forwards. The
foramina for the optic and oculomotor nerves are now
completely enclosed.

Several noteworthy changes have occurred in the quad-
rate (^). Its body and descending process have grown
broader and thicker, and two lateral projections from the
latter form a transitory support at the base of the bal-
ancer (sm). At the time of its most complete development
this support has the form of a shallow cup, the rim of
which coincides with the circumference of the base of
the balancer. The ascending process has extended up-
ward and has fused with the posterior end of the trabec-
ular crest. A slight backward projection from the body
of the quadrate is the first trace of the otic process.

Third STAGE. — Larva twelve mm. long (Figs. 4-7).
The distal ends of the occipital processes {ocp) have
fused with the postero-dorsal walls of the otic capsules,
and their proximal ends have fused with the posterior ends
of the parachordals. A solid floor is thus formed beneath
the medulla, and the jugular foramen {j) is enclosed by
cartilaginous walls.

The parachordals (p) with the notochord now form a
complete basilar plate below the posterior half of the
brain cavity except at one small place (/*) upon the left
side which still remains unchondrified. With the excep-



94 BULLETIN OF THE ESSEX INSTITUTE.

tiou just mentioned, the lateral margins of the parachord-
als are now everywhere continuous with the floors of the
otic capsules.

The otic capsule (o) now presents the typical capsular
form, covering by far the greater part of the surface of
the auditory vesicle. The median wall is beginning to
form along the dorsal margin and at the two ends of the
capsule, leaving two unchondrified spaces in the middle
and ventral region ; a large anterior one through which
pass the seventh and eighth nerves and the endo- and
perilymphatic ducts, and a smaller fontanelle lying pos-
tero-dorsally to the first. In the floors of the capsules
are the foramina for the exit of the branches of the seventh
nerve (vii) . Upon the left side the two branches of this
nerve pass through the two ends of a transversely elon-
gated foramen, while upon the right side they pass
through two separate foramina formed by the fusion of
the middle portions of the anterior and posterior walls of
the originally elongated foramen. Behind the foramina
for the seventh nerve and somewhat farther laterally is the
large fenestra ovalis (fo). The stapes (s) which arises
from a separate centre of chondrification occupies the
anterior end of the fenestra.

The only noteworthy changes in the trabeculoe are a
general strengthening and an increase in the size of the
cornua (c). The quadrate has become more solid
throughout all its parts except the processes which were
at the base of the balancer in the preceding stage. They
have disappeared together with the balancer, leaving a
single conical process in the place they formerly occupied.
The otic process (op) extends considerably farther back-
wards than before.

Fourth stage. — Larva thirty-nine mm. long. Gills
not yet atr(yphied (Figs. 8-11). The ventral portion of



THE CHONDROCRANIUM IN THE ICHTHYOPSIDA. 95

the occipital arch is in essentially the same condition that
it was in the third stage. So also are the parachordals,
except that the union with the capsular floor is now com-
plete upon both sides.

The otic capsules present several new features. From
their point of fusion with the occipital processes marginal
expansions (Figs. 9 and 11, loc) extend medially over the
sides of the cranial cavity. Passing forwards they approach
each other and unite to form the synotic tectum {st)
which terminates anteriorly in a short median process
{tm) the "tjeniatecti medialis" of Gaupp. In the me-
dian wall of the capsule there are now four small aper-
tures, of which three (Fig. 11) lie in a horizontal row
near the floor of the cranium, while the fourth is more
dorsal in position. Passing from in front backwards, the
first foramen of the row is the one traversed by the
seventh and one l)ranch of the eighth nerve {yii-\-viii).
The second branch of the eighth passes through the sec-
ond foramen (vui), and the third aperture of the row is
traversed by the perilymphatic duct (pf) . The fourth
aperture, higher up in the wall above the foramen for the
second branch of the eighth nerve, is the foramen for the
endolymphatic duct (ef).

At the anterior end of the otic capsule there are three
new connecting cartilages joining it with the trabecula on
the one hand, and on the other with the quadrate. The
process joining the postero-dorsal point of the trabecular
crest with the opposite wall of the capsule is relatively
slender ; w^hile the other two processes, the otic (op)
and palato-basal (j^^), iu*e formed by the fusion of u greater
part of the dorso-median surface of the body and otic
process of the quadrate with the adjacent wall of the cap-
sule and the margin of the basilar i)hite. A blood vessel,
which passes dorso-ventrally around the anterior end of



96 BULLETIN OF THE ESSEX INSTITUTE.

the capsule, is the only line of demarcation between the
otic and palato-basal processes. A large chamber is en-
closed between the posterior end of the trabecula, the
anterior end of the capsule and the bars connecting them
dorsally and ventrally. The ascending process of the
quadrate passes across its external surface, separating a
dorsal and a ventral foramen. The Gasserian ganglion
occupies this chamber and from it pass out the ramus
ophthalmicus profundus {rp) through the ventral fora-
men, and the rami ophthalmicus superficialis (/"«), maxil-
aris (rm), and mandibularis {m), through the dorsal
foramen.

The foramina by which the rami of the seventh nerve
leave the otic capsule are unchanged, except that now
there are two upon each side and that they are consider-
ably reduced in size. The fenestra ovalis {fo) is now
nearly filled by the stapes (s) , which has a slight promi-
nence directed outwards and upwards from the antero-
dorsal angle of the cartilage towards the otic process of
the quadrate. These cartilages, however, do not become
united at a^ay time during the development of Amblystoma
as they do in some other forms.

The trabeculse {t) are of nearly uniform size from their
junction with the parachordals to the point where they
meet in front in the ethmoid plate (e). Optic and ocu-
lomotor foramina are of equal size, both being small. The
ethmoid plute (e) , arising by the fusion of the anterior ends
of the trabeculse in the median line, forms a continuous
floor beneath the anterior end of the cranial cavity, the
nasal septum {ns) and portions of the olfactory organ.
In front it terminates upon each side in a conical process.
Laterally a freely ending process (c) extends backwards
along the ventral surface of the olfactory organ. This
and the adjacent parts of the ethmoid plate are develop-



THE CHONDROCRANIUM IN THE ICHTHYOPSIDA. 97

ments of the cornua of the earlier stages. In the same
plane with the ethmoid plate and just behind its posterior
end, a flat antorbital process {anp) projects from the side
of the trabecula and, curving forwards, terminates directly
behind the backward projecting process of the ethmoid
plate.

A broad nasal septum rises from the middle of the
ethmoid plate separating the two olfactory organs and
forming the anterior wall of the cranial cavity. Bars of
cartilage, which I have called the tectal cartilages (tc),
connect the antero-dorsal points of the trabeculae with the
opposite points of the septum, roofing over the olfactory
foramina and forming the bases from which curved pro-
cesses, laminaj cribrosee (e), extend outward, downward
and forward, covering over the posterior ends of the
olfactory organ.

The quadrate (q), besides its fusion with the otic cap-
sule as already mentioned, now presents a well developed
pterygoid process (pt), a C3dindrical rod of cartilage
joining the main part of the quadrate at the point where
the ascending process meets the body. Its general direc-
tion is forwards, parallel with the trabecula as seen from
above, and downwards with a slight outward curve near
the tip which lies just below the ventro-median surface of
the orbit.

Fifth stage. — Young Ambly stoma sixty-nine mm.
long. Gills entirely atrophied (Figs. 12-13). At this
advanced stage in the development of Amblystoma, ossi-
fication has occurred to so great an extent that large
portions of the older cartilages have disappeared, giv-
ing the chondrocranium a l)rolven and ragged appearance,
especially in the otic region. The median capsular wall,
the anterior end of the basilar plate and portions of the
occipital arch, and the trabecuUe are entirely replaced

ESSEX IN'ST. BULLETIN, VOL. XXVIII 7



98 BULLETIN OF THE ESSEX INSTITUTE.

by bone. At the same time the whole skull has increased
in breadth as compared to its length.

The synotic tectum (Fig. 12, st) is completely sepa-
rated from the remnants of cartilage formins: the otic
capsules, and the basilar plate Q9) is reduced in length to


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