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MARINE BIOLOGICAL LABORATORY.

Received
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*,* No book or pamphlet is to be removed from the Lab-
oratory without the permission of the Trustees.

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THE JOURNAL

OF

Comparative Neurology

AOUWARTERLY PERTODICAL

DEVOTED TO THE

Comparative Study of the Nervous System.

EDITED BY
C. L. HERRICK, Professor of Biology, Denison University.
ASSOCIATED WITH

OLIVER S. STRONG, Columbia University,
C. JUDSON HERRICK, Denison University.

VOLUME VI, 1896.

PUBLISHED BY THE EDITORS.
GRANVILLE, OHIO, U. S. A,
R. Friedlander & Son, Berlin, European Agents.

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The Journal of Comparative Neurology.

Contents of Vol. VI, 1896.

MARCH, 1896.
Pages 1-58, i-xliv. Plates I-VIII.

ILLUSTRATIONS OF CENTRAL ATROPHY AFTER EYE INJURIES. By
CoE Herricks With Platten 2 2 SS eae ae oe Soe ees
LECTURE NOTES ON ATTENTION. AN ILLUSTRATION OF THE EmM-
PLOYMENT OF NEUROLOGICAL ANALOGIES FOR PSYCHICAL PRO-
BLEMS» |) BY GZ. Plerreck 2 ost Bea ee eee
A NOTE ON THE CEREBRAL FISSURATION OF THE SEAL [PHOCA
WELULINA- By erred. Lash) DuSe..) With Plate ili SS ae ee
MoRPHOLOGY OF THE NERVOUS SYSTEM OF CypRIS. By C. . Tur-
ers \ NV Plates DT Vil See ee eee a) Se eT NOUS
PRELIMINARY NOTES ON THE CRANIAL NERVES OF CRYPTOBRANCHUS
ALLEGHANIENSIS..” By V/e A McGrec0r (BiSGnes aan e een eee
ON THE THREE POINTS IN THE NERVOUS ANATOMY OF AMPHIBIANS.

By, 0/5) Ss) areestey., | ithe three) figures 2 se ee ae eee eee

IYRERARY NOTICHSS ti boc 05 SS he heh a ek Oe es
Effects of Alcohol on the Cortical Nerve Cell --_.--_.----
Structure of Nerve Cells after Electrocution --.-..------__
Cortical Pathology of Permanent Dementia -------_._-----
The Fenetians of the’ Frontal) Ropessic 2 ie es
Cerebral Reesivestion= = 22 22 ee eee Se ee
Motor Functions of Dorsal Spinal Nerves ---.-...--------
Spiral Fibers in the Invertébratesuc ! 2222 222552250222 202
Structure of ‘the Dhalamus 322 Oy eee eee ose ee
he) Lateral) Line System oft Amphibia se) oso
Brains; of Sallropsida isa ase aoe ee ee ee
Frophte - Nerveses 225.555 sis ob an le oe a el
Ampullo-oculo-motor Connections 222 sake se ase eke
The Initial Stages of the Degeneration of Nerve Fibers___
Cortigal: Olfactory Appartus: 2.5202 be eee eee
Fiber Connections of the Olfactory Lobe of Man-__-----.
The Relation of Sensory and Motor Areas of the Cortex_.
Is\.the Decorticated: Dog/Consetous/? x24 see ee
The Paraphysis
Be ING wy JOU a eee
Structure of the Cytoplasm of the Nerve Cell....---.-----
the Pons|:Varolii) of) Mansi. 2s. Sees. ee ee

The Influence of the Cerebrum upon the Excretion of Ni-

trogen ——___- ee
Nerve) Permini‘of, the (Prostate "2252 sae eee ee
Demonolatry of the Nineteenth’ Centuryi2222222e2se. ee noe
he ‘Growth of ‘the (Brains 222 522-2 eee ee
Recent Studies in the Forebrain of Reptiles__-__.-..___--.

Modifications of Nerve Cells in Different Functional States_
‘The* American? Lobster 2222-22-02 0 eee eee ee
Pain in the Pectoral Region Sympathetically Accompanying

Irritation of; ithe) Horearmce a2 eee ee eee eee
Corrigendum ea acne eee eee

JUNE, 1896.
Pages 59-132, xlv-liv. Plates IX-XIII.

COMPARATIVE ANATOMY OF THE INSULA, By Tracy Earl Clark, B.S.
With Plates) EX- Xo 82 SS ooo ee rte eee ee
REVIEW OF THE GOLGI METHOD. By Olver S. Strong, Part I_-----
THE DorsAL SACK, THE AULIX AND THE DIENCEHPHALIC FLEXURE.
By, Bs iGs Wilder 2252 Ife Sea ea eee eee ek. wane
THE EcTAL RELATIONS OF THE RIGHT AND LEFT PARIETAL AND
PAROCCIPITAL, BISSURES., By (65) Goui2ideree ene ne a ae
EDITORIAL. NFEURONYMIC PROGRESS IN AMERICA-.....- Seon k so seae
EITERARY, (NOTICES 2o22--0--5— = a Bie Ae Serres CS ee ee
The Development of the Brain and Sense-Organs in Elas-
mobranchs 222002 222225, Boe ee eee eee

the) Sensory) Physiology (of vActinianse= sor -ss-se- soe en ea

Phe; Histology: of the) Myclone20e2 2 aes eee weno eee
Anatomy, of the ‘Gerebrum of; Notonyctes/222=_-2--2=- eee
Romanes on Weilsmannisim] = ee eee ae
Germinal(/Selection: 22 [223-2 se ee ree aie os. 2

the Psychology vofivAttentionsse === eee eee

Studies from the Yale Psychological Laboratory_...-----_-

The Embryology of the Medulla of the Rabbit-_.._______
Wranismis 222212 528 Sees Ne ie ae eek

DECEMBER, 1896. Double Number.
Pages 133-352. Plates XIV-XXII.

THE BRAIN OF THE BEE. A PRELIMINARY CONTRIBUTION TO THE
MORPHOLOGY OF THE NERVOUS SYSTEM OF THE ARTHROPODA.
By #..C. Kenyon, Ph.D. With Plates XIV-XXIT_2....-=..-.
THE ORIGIN AND GROWTH OF BRAIN CELLS IN THE ADULT Bopy.
By \oward Ayers cts iin ots) COs ee ee oe
THE INNERVATION OF THE AUDITORY EPITHELIUM IN MUSTELUS
CANIS, DEIGAY.t4! Byres, (ore al hee a een ee eet ee
NEURAL TERMS, INTERNATIONAL AND NATIONAL. By Burt G.
Walder MOD sues Sees ee soe Ce ee Ap ee eae ee

xxvi
XXVil
XXVii
XXXVI
XXXVili
xli

xliii

xliv
xliv

58
101

128

129
131

xlv
xlv

“xl vii
xl viii
xlix

133
211
214

216

ILLUSTRATIONS OF CENTRAL ATROPHY AFTER
EYE INJURIES.

With Plate 1.
Gb SHerrick:

In the present paper it is not hoped to add anything new
to the vast and.daily augmenting literature of the visual connec-
tions but simply to place in accessible form some data accumu-
lated, with the hope of ultimately making a careful study of the
peripheral connections and particularly the central mechanism
of accommodation. The difficulty of finding figures illustrating
the actual results of the atrophies due to the destruction of the
eye has disposed us to print our own diagrams with a running
commentary. The material consists of serial sections of the
brain of two rabbits whose eyes were operated on shortly after
birth and before the eyes had opened. Series 292 is from a
rabbit operated on August 25th, the right eye being removed.
Killed November Ist, when nearly full grown. Series 297 is
from a rabbit from which the left eye was removed September
Igth, being then one day old. It was killed December 1gth.
As these brains were intended to compare with control series of
normal brains and were to be used primarily in the study of the
cells, etc., they were stained with sublimate hematoxylin and
fuchsin. In both cases the loss of vision was complete and the
wound closed by first intention without suppuration, though in
one the globe of the eye and the muscular attachments were
less completely destroyed than in the other. Unfortunately
there was no opportunity for careful post-mortem examination of
these conditions which can be inferred from the state of atrophy
found in the sections. It will be seen that the atrophy in the
optic tracts was much more complete in No. 297, that is in the
one operated upon within 24 hours after birth, than in the other
which was operated upon a few days later. We begin with No.
292, commencing behind the chiasm. The optic tract on the right

2 JOURNAL OF ComPARATIVE NEUROLOGY.

side is intact except that the innermost band of fibres is filled
with granules to such an extent as to be decidedly darker than
the ectal portions. The degenerate portion does not embrace
more than a sixth of the whole. On the left side (that corres-
ponding to the injured eye) the conditions are exactly reversed.
The outer five-sixths is degenerate and filled with irregularly
disposed granules, while the ental layer appears normal or near-
ly so. Under a moderate power (1-5 in. obj.) the difference be-
tween the degenerate and normal tracts is conspicuous. The
unaltered portions have the nutritive granules arranged in regu-
lar files of 6-8 between the fibres and these rows are disposed
at approximately equal distances. In the degenerate portions
the granules are not only relatively more numerous but they
are dispersed with absolute irregularity. The fibres are no
longer approximately parallel but are irregularly meshed. The
sheaths are partly dissolved and the myelin completely ab-
sorbed. (Cf. Fig. 11.) The tectum in this series is somewhat
larger on the right side but there are no demonstrable histolog-
ical differences.

Passing caudad to the level of the exit of the oculo-motor,
we find the right root entirely absent while its fellow is normal.
The right nidulus of origin is also absent while the interpedun-
cular niduli, which some writers persist, in spite of abundant
evidence, in regarding as accessory third niduli, are intact on
both sides. It is not possible to identify positively any of the
elements of the missing nidulus though shrunken adendritic
elements occur in the site. (Fig. 3.)

At the level where the interpeduncular nidulus ends cau-
dad, the cells of the fourth nidulus appear in the sections and
are more numerous on the right than on the left side. Still
there is no conspicuous difference in this subject between the
two sides. The dorsal longitudinal fasciculus becomes more
concentrated at this point and the nidulus lies directly dorsad of
it in a stroma of deeply staining material. There are about the

1In discussing the sections it may be premised that the cephalic aspect of
the section is presented so that the right side of the section is the left side of
the figures.

HEeRRIcKk, Central Atrophy After Eye Injuries. 3

same number of fibres in the root of the fourth nerve on either
side. (See Fig. 4.) The external portion of the fourth nerve
of the right side is apparently wholly degenerate while its fel-
low of the opposite side is intact. For some reason, then, the
degenerative process has destroyed the central tract and nidulus
of the third nerve but not those of the fourth, though the ex-
ternal part of the latter has disappeared. We find no central
tracts degenerate between the fourth and sixth nerve niduli, but
the latter has as completely disappeared as in the case of the
oculo-motor. Nothing is left of root, tract or nidulus. The nid-
ulus of the left side lies, as usual, just laterad of the genu of
VII and its root tract turns sharply mesad beneath the VII
fibres and then passes directly ventrad to the root. Some traces
of the sheath may be found by careful search in the course of
the root of the other side.

The result of the operation, then, has been as follows: (1)
degeneration of the lateral three fourths to five sixths of the
left optic tract and of the mesal one fourth to one sixth of the
right tract, (2) proportional atrophy of the optic tecta, most
marked on the left side, (3) obliteration of the nidulus, root
tracts and roots of III and of the external part and ‘roots of IV
on the right side, (4) the obliteration of VI on the left side as
completely as III. Negatively, the central portions of IV are
unaltered and the interpeduncular niduli are intact.

The rabbit of series 297 was operated on earlier and the
results are rather of the nature of atrophies than of degenera-
tions. The diameter of the left optic nerve is somewhat more
than one fourth that of the right. At the chiasm, as seen in
Fig. 7, the proportions are about the same. The degenerated
portions are almost completely absorbed leaving only atrophic
phenomena. Sections further caudad show very distinctly the
atrophy in the tract. (Fig. 8.)

At the proper level the corpus geniculatum of the left side
appears with its tracts, but on the other side it seems quite ab-
sent. There are no degenerative changes to enable us to trace
the tracts cephalad to the cortex but there seems no reason to
doubt that they are atrophic throughout. The reduction in the

4 JOURNAL OF COMPARATIVE NEUROLOGY.

tectum has gone on and perhaps nearly reached its limit. The
left tectum is fully four times the size of the right but the inti-
mate structure is not obviously different.

Passing to the oculo-motor apparatus, the third nerve roots
are both present and it requires close examination to discover
anything unusual in them but the fibres are atrophied to some
extent. The niduli, on the other hand, are nearly completely
atrophied. The cells are nearly all shrunken and shrivelled and
lie in large perilymph spaces. The contrast between these cells
and the unaltered cells of the interpeduncular niduli is instruc-
tive. (See Fig. 10.) In this case the fourth nerve has shared
the fate of the third. While the atrophy has been more marked
on the right side than on the left both are affected. The series
unfortunately does not extend to include the sixth, but it is

probable that the same condition existed in it. Our material is
inadequate to illustrate the changes in the tracts and niduli of

the second order.
In attempting to analyse the various alterations with which

we here have to do it is necessary to distinguish degeneration from
atrophy and aplasy, the latter being a failure to develop asa
result of operative interference. See Singer and Munzer,
Denksch. Kaiserl. Akad. 2. Wien. 1890.

DESCRIPTION OF FIGURES.

Fig. z. Transection of rabbit brain (No. 292) immediately cephalad of
the optic tecta, showing the atrophy of the tracts of the left side. The section
is not exactly transverse.

Fig. 2. Section through the tecta showing the atrophy of the left side and
in the nidulus numbered ‘‘3.”

Fig. 3. Section at the roots of the third nerves showing the absence of the
right nidulus and root.

Fig. 4. Portion of a section through the fourth nidulus showing that it is
not affected by the atrophy.

Fig. 5. Section at the exit of the sixth showing the absence of the fibres
of the right side.

Fig. 6. Part of a section further caudad showing the complete atrophy of
the right nidulus.

Fig. 7. Part of a transection of a rabbit brain (No. 297) from which the
left eye was removed at birth, showing the degeneration of the right tract.

Fig. 8. A-section further caudad.

Fig. 9g. Section at the habenz showing atrophy in tract of second order
on the right as well as in the optic tract.

Fig. ro. Cells from the nidulus of the third (A) and from the interpedun-
cular nidulus (B) to demonstrate the atrophic changes in the former.

Fig. 11. Normal and degenerate portions of optic tract from 292, 8.

LECTURE, NOTES “ON ATTENTION.

An ILLUSTRATION OF THE EMPLOYMENT OF NEUROLOGICAL
ANALOGIES FOR PsycHICAL PROBLEMS.

C. L. HERRICK.

At once a most difficult and a most important group of
problems is offered in the study of attention. The importance
grows, on one hand, out of the close connection of attention
and its cultivation with the practical obligations of pedagogy,
and, on the other, out of the theoretical relations of attention
with fundamental mental endowments like volition and apper-
ception.

The source of the difficulty is also two-fold; first, the at-
tempts at experimental study of attention suffer from the ambig-
uity that, when all is done, the results are all apparently physi-
ological rather than psychological. But this is only a conspicu-
ous instance of what is true of experimental psychology as a
whole. Care is necessary to discriminate the content in the
mind from the physical accompaniments unless one is prepared
to ignore that distinction entirely. The second difficulty is that
different observers have different theoretical points of view and
an unbiased stand-point is as impossible as it would be unpro-
ductive. The purposeless and indiscriminate collection of facts
rarely furthers science. Working hypotheses and a_ willing-
ness to reject them when evidence requires are the theoretically
desirable conditions, though in practice the willingness to reject
is on the part of some other observer or.critic (none the less
salutary in the result).

It seems proper to divide attention into (A) external or
sensory and (B) internal or cognitional. This is merely a work-
ing division corresponding to the common experience that some-
thing may ‘‘catch the eye,’ on one hand, and that we ‘‘con-
centrate our thought”’ ona problem, on the other. It would

b

6 JOURNAL OF COMPARATIVE NEUROLOGY. .

seem that popular language has crystallized an opinion that in
one case the process is passive and in the other active. We are
slow to reject the calm and impartial dicta of common sense
—in fact, in some sense, this dictum is likely to be found cor-
rect, though the meaning of active and passive in such connec-
tions may suffer a good deal as the result of analysis.

External Attention.—One of the first evidences of awaken-
ing psychical life in the child is seen in the motions of the eye-
balls as he attempts to follow moving objects, and one of the
last evidences that is given that the departing spirit still hovers
over the threshold is the same seeking motion of the eyes. As
the most direct and unbiased avenue to consciousness, vision is
the best sense from which to study the phenomena of external
attention. Now if the eye be fixed upon a given field of view
coinciding with the visual field of the retina it is evident that all
parts of the field are capable of producing an impression on the
retina and so on the nerve fibres and brain; in fact, each such
spot does stimulate a point in the brain corresponding to the
spot in the retina on which it falls. This neural irritation is not
yet in consciousness but is a part of the ‘‘content of sense,”
or sensory material for consciousness. Returning to the retina,
if the field of view be uniform and uniformly illuminated and
the gaze be fixed upon it under circumstances excluding other
visual distractions a small disc will appear in the centre of
the field of view which is somewhat more bright than the sur-
rounding portions. :

This little experiment is the physiological aspect of the
fact that there is in the axial pole of the retina a spot in which
only the cones are present and consequently the intensities of
light and shade are more vivid than elsewhere in the retina.
This relation would lose most of its significance were it not for
another relation connected with it.

1The descriptions of most of the experiments accompanying the lecture are
omitted as they are of such a nature as will readily suggest themselves to the
experienced reader.

Herrick, Lecture Notes on Attention. 7

Experiment.— Fix the single eye upon a faintly illuminated screen with per-
forations near the margin of the field and a shutter behind in such a way that
a ray of strong light may be revealed at will. Note that the axis of the eye in-
voluntarily turns toward the ijluminated spot. Vary the experiment by using
small colored images painted with transparent color and projected upon a trans-
parent part of the screen, etc. Now determine to resist this tendency and keep
the eyes immovably fixed on the original spot. Observe whether there is a
feeling of tension in the eye, a strain on antagonistic muscles of the neck or in
the scalp or even asense of tension in the brain. Interpret the results. Ob-
serve what happens when the subject is encouraged to expect the new impres-
sion on the right and then unexpectedly it appears on the left. A wider angle
than the actual retinal one may profitably be used in these experiments while in
other cases a diaphragm will be needed. In some it is an advantage to have
the head fixed while it might be instructive in the deviation experiments in
some cases to have the weight of the head counterpoised by braces under chin
and occiput suspended to a swivel in the ceiling

What is the result if the eye is centred on a bright, a varying, or a barely
legible object? Is there a conflict of interest ?

We have then in the eye a device for differentiating a part
of the field of vision by reason of which that portion is more
vividly reproduced in the brain and we have an anatomical adjust-
ment of the muscles of the eyeball to enable this sensitive
point to be turned upon any object which, by reason of the in-
herent intensity, usurps the position. More than this, there is
a very complicated system of nervous correlation reflexes which
must have developed pavit passu with the anatomical structure
by which the visual coordinations are affected anatomically.'

It is of fundamental importance to decide whether the
turning of the eye upon the vivid point in the margin of the
field is due to volition or is spontaneous and a pure reflex. It
seems certainly to be the latter. It may be noticed that in the
fixing of both eyes on any field there is a complicated coordina-
tion which has to be learned but passes out of voluntary con-
trol, so far as the details of the process are concerned, very
early. When any particular object is to be ‘‘ fixed ”’ in vision
the two macule luteze must be properly adjusted as ‘‘identical’”’
spots of the retina and when this is done all other parts of the
two images will fall on ‘‘identical” spots. Now when a bright

or vivid spot appears near the margin of the field we might

1 The instructor will review the visual-motor coédrdinating systems.

8 JOURNAL OF COMPARATIVE NEUROLOGY.

assume that the effect is the same as that of a false accommoda-
tion of the maculz and the instinct to correct it has potence to
make the new accommodation before an act of judgment can
adjudicate the question. ' Whether this is an entirely satisfactory
solution or not there is little doubt that external attention is of
the nature of a reflex which may or may not retain a relation
of subordinated connection with conscious processes. If care-
ful attention is paid to what goes on during these involuntary
acts of accommodation one may notice a certain sensation in
the eyeball and muscles usually not felt at all. Now even
where these sensational elements do not enter consciousness as
such (or at all) they are stored up along with the retinal sensa-
tion and may be employed in the formation of a sense of posi-
tion—a concept of a spatial nature. However obscure the
mechanism of this process, there is no doubt that it takes place.
When we exercise ourselves in the effort to mentally estimate
the position of various objects in the field of vision seen by aid
of momentary illumination and discover that this too is possible,
it simply seems to mean that associations have been fixed be-
tween lateral cells in the retina and the muscle sensations pro-
duced in bringing an image on the macula lutea through the
necessary arc to impose it on that spot.

Experiment.—Using a screen at a fixed distance from the eye the subject
practices the estimation of distances until a degree of familiarity with the
measures is obtained. Then in the dark try the same by instantaneous electric
spark. Note accuracy. Tabulate results. Now try the same experiment vary-
ing the duration of the illumination and observe whether there is an optimim
period and, if possible, whether the eye is moved. Compare the two methods
of estimation, 7. ¢., that where the eye motions are used directly and those

where they are used indirectly.

It is, then, obvious that the same class of sensations, viz.
those derived from the act of accommodation, may be used in
one case to produce asense of effort or may become, in another,
data for localization.

* Compare the labored attempt of ZIEHEN to explain this point. Lettfaden,
p- 134 et seq.

Herrick, Lecture Notes on Attention. fe)

E-xperiment.—Glance casually over a page of print and note whether some
phrase or word catches the eye. (The experiment is much more conclusive when
done unintentionally). What word emerged? On repeating this experiment
and glancing casually down the columns of the ‘*Times’’ the writer caught the
word ‘‘ college”? and ‘‘university’’ many times also the word ‘‘ association ’’
several times and hardly another word. <A house keeper looking at the page of
the ‘*Youth’s Companion ”’

?

saw ‘* cooking” and ‘‘sweeping” first.

The experiment may be conducted under scientific control in various ways.
Arrange groups of figures similar in size and body of shade, most of them un-
familiar, one or more familiar, and reveal them for ashort period (not too short),
or produce familiarity by exposing squares covered by some one or more of the
symbols as preparatory to the experiment. Note the effect of ‘‘ association.”’

The result of these experiments convinces that the selec-
tion of one out of many impressions to be placed in the favored
attitude in the sense organ is largely influenced by znterest
and faézt. The word ‘‘interest’’ is here used in a popular and
perhaps misleading sense. Probably in the sphere of the ex-
ternal sense these effects are all the result of habit. For exam-
ple, the reason that my eye caught the words ‘‘ college,” ‘‘ uni-
versity,”’ and ‘‘association’’ out of their places among others
was certainly not the superior interest which these words have
for me, for they emerged before there was any consciousness of
the interest. True, I had often associated in mind these very
words in interesting connections and had consciously gone about
to seek these words or passages containing them with the mind
‘‘loaded,”’ so to speak, for this particular game. The result is
a habit of selection which retains its unconscious power. The
number of cotemporaneous sensations received by any sense
is purely a matter of the structural adaptability of the organ or
its natural field. All of the impressions of a given field of
sense may become the content of that sense and so may exert
their appropriate effects in infra-conscious spheres of association,
etc., even though only part of them ever reach consciousness.
The discussion as to the possible number of cotemporaneous
sensations is based on a misconception. Though the content of
sense may be diversified only one thing is ever in the focus of
consciousness at a given time.

So far we have been dealing with comparatively pure cases
of external attention, but it is not to be denied that the con-

10 JOURNAL OF COMPARATIVE NEUROLOGY.

scious processes react on the sensory organs and modify their
functions. It is a familiar commonplace that the degree of at-
tention is very dependent on the feeling tone of a sensation.
Two points are to be noted here: first, that the greater number
of feelings associated with sense impressions have a practical
value for the life of the individual and have so acquired an im-
pulsive connection with external attention without calling con-
sciousness into play; and, second, that the very nature of feel-
. ings involves intensity of the stimulus (summation, on one hand,
and irradiation, on the other,) so that this comes under the head
of intensity as above. But let us turn to another form of this
activity. I resolve to attend to the excitations of some sense
or, aS we say, to keep eyes and ears open. This resolves itself
into a more or less fruitless attempt to accommodate the organ
voluntarily and results in for the most part ill-directed if not dis-
turbing oscillations in the tension of the organ. Thus when in
the night I strain the ear to catch a sound in no special locality I
become conscious of the fact that the tensor tympani and stape-
dius muscles are making castanets of my ears and audition is im-
peded rather than facilitated ; so when I strain if perhaps I can
make out another star in a vacant space I lose more than one
‘‘dimension”’ before visible. One becomes conscious of a
sense of effort in various organs, even in such as have no direct
connection with vision and also of alterations in the somatic sen-
sations. These sensations of effort, then, seem to us to prove
the presence of attention, even voluntary attention, when there
is absolutely no attention, for it is idle to speak of attention
when nothing is attended to. It is only a cavil to say that in
the case indicated there is attention to the sensations of effort.
Such reasoning is an endless chain. When we really attend to
something in the sensory sphere it is some specially selected an-
ticipated thing. Even in the general case of listening for a
noise we reproduce in thought one noise after another in ad-
vance. ‘‘It will prove to be a creak, or a scratch, or the like.”’
Imagination meets the visual impression more than half way.
‘Ts it a dagger that I see before me?”’ We are looking for
something—our attention consists in the scrutiny of the content

Herrick, Lecture Notes on Attention. II

of sense with a reproduced vestige as a guide. The repro-
duction may be of a very simple sort, as that of number—we
may be repeating mentally, simply ‘‘ how many?” as we scru-
tinize the sense content, but it is easy to see that the state
of things here is very different from that in case of external at-
tention—we are now dealing with a complicated central corre-
lation across if not wholly within the field of consciousness.
Internal Attention.—We have seen that internal attention
popularly lays claim to active and conscious effort, but we have
learned that such sense of mental effort may be, and sometimes
is, simply the association of muscular sensations and that inter-
nal attention implies a variety of coordinations in consciousness
and we need not be blamed if we fall to doubting the validity
of the sense of self-direction in internal attention. Internal at-
tention is connected with the process of comparison either of
the content of sense with some vestige or concept, or of two
or more psychical elements along themselves. Thus we receive
the advices from sense with a predetermined interrogatory, it
may be, ‘‘Is the new impression the same as some other?
Does it belong to the same class? Was it previously associated
with A,B, .or'€.?) Is it as .big,.as loud) as \ persistent, jeter?
In other words, we compare the new sensation with some stand-
ard in reproduction and form more or less implicate judgements
as to identity, similarity, difference etc., so that we find our-
selves projected into regions in the very penetralia of the psy-
chical life far from the supposed boundaries of mere attention.
This experience is enough to show that attention is not a fac-
ulty or independent activity of mind. Inner attention then
may be but the measure of the vividness of consciousness
under different conditions and attendant circumstances, whether
of presentations of sense or central processes. But, it is proper
to ask, what then becomes of the appearance of voluntary di-
rection of attention? If it were true that we can force our
minds to attend to any thing we choose, then this would become
a matter of volition and need not require a separate treatment.
Very brief reflection shows that we cannot attend to anything
we please, for, in the first place, it is necessary that the thing

12 JOURNAL OF COMPARATIVE NEUROLOGY.

should be presented to consciousness. We cannot attend to a
sensation not already a content of sense nor to an unreproduced
reproduction. We can not manufacture a sensation to ‘‘attend
to,’’ but can we perhaps reproduce a vestige not in conscious-
ness? It is evidently absurd. In the case of the various sense
contents we have seen that some have special attributes of in-
tensity or special reinforcing collaterals to adapt them to affect the
higher centres. May it not be true that the vestiges of con-
scious processes (memory material) may have similar differential
powers and special vehicles? The familiar fact that repetition
facilitates reproduction shows that these vestiges are capable of
being differentiated in their power of appeal to consciousness.
Now experimentally let us undertake to recall the name of the
man we met yesterday. ‘‘ Think’ as I may, no trace appears.
I wrinkle the brow and strain all sorts of antagonistic muscles
and set up a great sense of effort in the attempt to induce cere-
bral innervation, in fact, I do succeed in forcing an unusual sup-
ply of blood into the head and quickening the play of images
but none of them is the right one. Try anew tack! The pre-
sentations originally responsible for all the disturbance were of
—a person—a man—met yesterday—and we have exhausted
the associational images called up by ‘‘man”
‘‘Jones, Jenkins, Jaynes, etc.’’ let us dismiss them and see

—‘‘name ’’—

what ‘‘ yesterday”’ has to offer. The vestiges are fresher—they
rush upon me—more trouble to dismiss the undesired ones.

Certainly here they are! ‘‘ Broadway—hospital ambulance—
Dr. B’s clinic ’’—and, at last Dr. B. himself.- What could be
more simple, I have ‘‘ recalled the name.’’ No, but was not

what I really did the inhibiting of the undesired reproduction
in order to let the chain of association follow its own laws of
appearance? Thus we seem to have reached Wundt’s posi-
tion that attention is essentially the results of inhibition. We
cannot remain content with this conclusion for, first, practically,
we are unable by introspection to find evidence of any such
voluntary inhibition, second, theoretically, we seem to have
gained nothing by such an assumption for the source and nature
of the volition involved is as obscure as ever. What is certain is

Herrick, Lecture Notes on Attention. 13

that consciousness hovers from point to point in accordance with
laws some of which we are able to formulate, if not to explain.
Before leaving this point we meet the apparently legitimate crit-
icism that what has been said applies rather to reproduction than
to attention. Attention, it may be said, is not responsible for
calling data to consciousness but for retaining them when there.
However, observe that, if the conclusion that only one datum
can be in consciousness at once be correct, experience shows
that it is impossible to keep attention fixed for the fraction of a
second on absolutely one presentation. There is a constant flux
and alteration. Attention becomes then a set of rapidly re-
peated reproductions. In thinking intently of one thing we
limit the field of oscillation and cut off distractions as much as
possible, but the oscillations with the various resulting associa-
tions continue and give pregnancy to the meditation. Here
again inhibition emerges as the agent of attention. Here too
we are forced to reject the interpretation as above. The sense
of voluntary effort in attention we may agree with Ziehen in
ascribing to sensations of innervation, etc., that in no sense are
a cause of the attention. But we would not stop there, but be-
lieve that the sense of personal participation in our activities is
of a more complex character than that suggested by the Miins-
terberg-Ziehen school.

To understand attention then one must understand the na-
ture of consciousness. From its psychological side this is con-
fessedly insoluble and we must be content either to pursue our
search no further or to accept such suggestions as may come
from neurolcgy and philosophy. In taking the latter course we
are frankly entering a theoretical domain where only a balance
of probabilities and reasoning from analogy can serve us.

The organ of consciousness is the cerebrum and the great
and distinguishing character of the hemispheres is the unlim-
ited associational mechanism. All sorts of lower neural pro-
cesses which are to influence consciousness have their offices
here but these stations are all connected with each other. From
all that we know of the analogies of nerve force it does not
seem inherently impossible that a current from an eye centre

14 JOURNAL OF COMPARATIVE NEUROLOGY.

might if permitted to reach an auditory cortical station, produce
some sensation—perhaps of a new kind of sound. ‘The anat-
omical relations prevent an interference of this kind but the re-
sults of the current’s action on the eye station may meet and
modify a similar product of an ear station in a centre of a higher
order. In the frontal lobes, perhaps, is a projection system of
the highest order where the last fine adjustments occur. There
must be, it would seem, a constant balance or resolution of
forces in such a system. The centre of tension, if it could be
seen, would be found flitting with greater rapidity that the re-
flected disc of the electrometer of a testing outfit from one sta-
tion to another in obedience to the various disturbances of equl-
librium—due here to a new sense presentation, there to a nu-
tritive adjustment removing a temporary inhibition. There is,
to all appearance, only this sort of physiological unity possible.
The only psychological unity is the unity of consciousness. Is
there a connection between the two? Weare inclined to an-
swer in the affirmative. While it seems necessary from consid-
erations not necessary to enter upon here to consider conscious-
ness itself a spontaneity of a higher than nervous nature, it is
apparent that it finds its physical condition in this vortex or ner-
vous ‘‘centre of gravity.”’ If this or something like this is the
truth about consciousness, then attention is a name for the play
of consciousness and a study of its laws reduces, on one hand,
to the investigation of neural equilibrium and, on the other, to
a natural history of consciousness. The conditions of inner at-
tention are those of association and inhibition.

XP NOEE ON, ViHip “CEREBRAL S PISSURATION °O
THE SEAL) (Phocalvitulina)."

PIERRE) A.) Fisa, 1D) Se;

Bureau of Artal Industry, Washington, D.C,

The specimen was not more than one year of age, and came
into my possession in November, 1895. During the manipu-
lation incident to the process of hardening some general resem-
blance of the fissural pattern to that of the feline or canine type
was noticed. The pia was removed and the fissures studied at
an intermediate stage of the hardening before their walls had
lost their pliancy.

Dr. E. C. Spitzka (1890) in a preliminary paper (Ameri-
ean Naturalist, XX VI. 115-122) refutes some rather grave mis-
representions by Theodor, 1887 (Das Gehirn des Seehundes,
Inaugural Dissertation) one of them being the existence of
a so-called Commissura Suprema an elongated transverse mass
of fibers lying dorsal to the Callosum, an artifact pure and sim-
ple. Theodor further states that ‘‘ the Seals and (ordinary)
Carnivora are in their cerebral organization today widely sep-
arated and their common origin must be sought in a remote
geological period.’”’ In regard to this Spitzka states that the
examination of a series of brains beginning with the mink, the
fresh and salt water otters and passing through the eared to the
earless seals would show about as beautiful a transition asa
morphologist could well desire.

In the specimen at hand the frontal region of the brain is
very much fore-shortened and gives the appearance of consider-
able width. On the lateral aspect the Sylvian fissure is well
marked and pursues its usual dorso-caudal course. Just in front
of it and extending vertically (dorso-ventrally) is another un-

' Read at the Meeting of the American .Anatomists Dec., 1895, Philadel-
phia, Pa,

16 JOURNAL OF COMPARATIVE NEUROLOGY.

named fissure which superficially seems to run into the Sylvian
at its base. This vertical fissure Spitzka has taken for the Syl-
vian. He describes it as follows: ‘‘ It is the enormous hyper-
trophy of this field (auditory cortical) which crowds the Syl-
vian into its unusual vertical, nay anticlinal position.’”’ The
blunt frontal end of the cerebrum is an additional reason for
making the above condition possible but this view leaves a well
marked fissure in the usual situation of the Sylvian unaccounted
for. This opinion is still more difficult to accept when we come
to ‘‘sound ”’ the fissures (examine their depths). The vertical
and the true Sylvian fissures meet superficially at the latero-ven-
tral angle of the cerebrum and if the sides of the Sylvian be sep-
arated, it will be seen that the vertical fissure instead of directly
joining the Sylvian becomesa submerged fissure, at this point
corresponding to the preopercular area of the human brain,
and crops out again on the ventral surface on the front or ceph-
alic wall of the mouth of the Sylvian. In reality the vertical is
an open surface fissure in its dorsal half and overlapped by the
cortex (supergyre) in its ventral half. This condition is found
on both sides.

Tiedemann (Icones cerebri simiarum et quorundam mam-
malium rariorum, Hidelbergia, 1821), ina figure of the base
of the seal’s brain shows the ventral outcropping of a fissure in
the cephalic wall at the base of the Sylvian which is none other
than the terminus of the vertical. The present specimen con-
firms this exactly.

In the feline brain the fissure approximating most nearly
to this vertical fissure of the seal would, in my opinion, be the
anterior fissure; for if the frontal region of the cat’s brain
could be moulded by any process of growth to the relatively
fore-shortened condition of the seal’s brain the parts would as-
sume very much the same relations. The fissuva postica of the
cat’s brain does not seem to be represented in the seal.

The super-Sylvian and the post-Sylvian are well marked.
The two are continuous with each other at the surface on both
sides; but at their union two branches are given off on the left
hemicerebrum and one on the right hemicerebrum. The pres-

Fisu, Cerebral Fissuration of the Seal. 17

ence of subgyres at this point makes it very difficult to get ac-
curate soundings ; and whether the union of these two fissures
is anything more than superficial is therefore somewhat un-
certain.

The lateral fissure is long and tortuous and well on the dor-
sal surface; its average distance from the intercerebral cleft
being about one centimeter. On the left side it unites super-
ficially with the super-Sylvian at the level of the vertical anter-
ior fissure. On the right side the union is deeper and in ad-
vance of the anterior. The caudal termination of the lateral
fissure is at the extreme end of the crebrum and is in the shape
of a T due to the union of a small transverse fissure, possibly
the lunate of the cat.

The ansate is a well developed fissure and is almost directly
vertical in its course. It arises within less than a centimeter
of the mesal surface caudal to the cruciate and extends ven-
trally to about the level of the superficial confluence of the an-
terior and Sylvian fissures. On each hemicerebrum there is a
superficial union of the super-Sylvian with the ansate but in
each there is evidence of a shallow (vadum) between them. -

The diagonal of the cat is not distinctly represented in the
seal, unless on account of the very much foreshortened con-
dition it has become confused with the ansate or cephalic por-
tion of the super-Sylvian.

The super-orbital fissure arises from the base of the ol-
factory bulb, which covers its origin, and extends in an oblique
ventro-caudal direction to within one half a centimeter of the
basi-Sylvian.

The olfactory is a very short but deep fissure in which the
delicate olfactory crus is almost completely imbedded.

The cruciate fissure of the right side extends for a distance
of a centimeter and a half on the dorso-lateral surface and has
considerable depth. It also extends a centimeter and a half on
the mesal surface. Very near the dorso-mesal margin a dorsal
branch is given off and nearly opposite this is a ventral branch.

The left cruciate fissure extends less than one centimeter
on the lateral surface, but a minor fissure connecting with it

18 JOURNAL OF COMPARATIVE NEUROLOGY.

superficially makes it apparently extend over two centimeters.
As with the right hemicerebrum a dorsal and a ventral branch
are given off on the mesal surface, near the dorso-mesal margin.
The cruciate continues superficially as far as the splenium with
a fissure corresponding to the super-callosal. A super-callosal
seems to be represented on the right side, but it does not join the
cruciate.

The splenial fissure arises at the dorso-mesal margin of the
hemicerebrum at about the level of the splenium. It is oblique
in its direction (ventro-caudal) and is more vertical than hori-
zontal. It extends well on to the ventral aspect (about one
centimeter).

In the dog and cat cerebrum the fissures are for the most
part isolated and distinct ; but in the seal there are numerous
branches given off and rather an unusual amount of confluence
of the larger fissures. The complexity is increased by the sinu-
ous course and the presence, below the surface, of numerous sub-
gyres or outgrowths along one wall, while the other wall overlaps
and becomes more or less concave in adapting itself to this
growth. This sinuosity at the depth of the fissure (much more
marked than at the surface) makes an accurate sounding well-
nigh impossible. The obliquity of the fissures and the over-
lapping of one wall by the other, especially in the case of the
ventral portion of the splenial amounts to almost an operculum
or poma. These conditions in many regions render the accu-
rate determination of a fissural integer very difficult.

Underlying all there seems to be a fissural pattern not un-
like that of the feline to which are added the various complex-
ities above enumerated, but these are hardly sufficient to ob-
scure the carnivore type.

Fisu, Cerebral Fissuration of the Seal. 19

PATE Uk:

REFERENCE LETTERS FOR THE FISSURES.
ans,—ansate. mi.—medilateral.
ant,—anterior. Post.—postica.
Cal.—callosum P. Syl.—post-Sylvian.
Con.—confinis. rh.—rhinal.
Cor.—coronal. sc.—supercallosal (?)
Cr.—cruciate. so.—superorbital.
Diag.— diagonal. spl.—splenial.
7.—lunate. Sp. Syl.—super-Sylvian,
Zat.—lateral. Syl.—Sylvian.

m.—marginal.

EXPLANATION OF FIGURES.

In all of the figures the important fissures are drawn with heavy lines and
the minor fissures with light ones. The first four figures were photographed
and enlarged drawings made. A small cross indicates a shallow depth of the
fissure at that point. The fissural names are based upon those used in the
Anatomical Technology (Wilder and Gage).

fig. z. Lateral view of the left hemicerebrum of the seal.
Fig. 2. Mesal view of the right hemicrebrum.

Fig. 3. Lateral view of the right cerebrum.

Fig. 4. Mesal view of the left hemicerebrum.

fig. 5. The base of the seal’s brain, after Tiedemann. This figure shows
the ventral outcropping of the vertical anterior (?) fissure in the cephalic wall
of the Sylvian.

fig. 6. The dorsal aspect of the seal’s brain, after Tiedemann.

Fig. 7. Lateral aspect of the left hemicerebrum of the cat (diagrammatic).
Fig. 8. Mesal view of the cat's right hemicerebrum (diagrammatic).

fig. g. Schematic type for brain of Carnivora, after Pausch.

fig. ro. A cross section of a fissure, to show the obliquity.

Fig. zr. A diagram to show the difference in the course of a fissure at its
surface and depth. The heavy lines represent the fissural walls at the surface.
The dotted lines and arrows represent the deep course of the fissure.

MORPHOLOGY OF THE NERVOUS SYSTEM OF
CYPRIs:

GC, AHS SP URNER:

With Plates ITI—V/1/I.

Introduction.

About three years ago, on publishing a, ‘‘ Preliminary
Note on the Nervous System of the Genus Cyfrzs,”’ I promised
to publish, in the near future, a histological monograph on the
Ostracoda. This paper is intended as the first installment of
such a monograph. In this communication it is intended to
give a detailed discussion of the central and peripheral nervous
systems of the Cypride.

Owing to its large size, Cypris herrickt Turner has been
selected as the type to study. To eliminate all mere size-vari-
ations, Cyprinotus incongruens Ramdohr has been used as a
check. For the study of the central nervous system, these
two species have been considered representative types of the
Cypride ; but, in studying the peripheral sense organs, use has
been made of all accessible genera. These genera are: Can-
dona, Cyclocypris, Cypria, Cypris, Cyprinotus, and Cypridopsas.

This paper being the embodiment of neurological investi-
gations, any prolonged discussion of extra-neural systems
would be out of place; yet, in order to facilitate a comprehen-
sive discussion of the nervous system, a few terse histological
statements upon the associated systems have been made.

BIBLIOGRAPHY.
Craus: (C:
1. Ueber die blassen Kolben und Cylinder an den An-
tennen der Copepoden und Ostracoden. Wairzburg

naturw: Let.’ 3, Bd;, 1860, Tat. Vil, Pisa.

TURNER, Nervous System of Cypris. 21

2. Ueber die Organization von die Cypridinen. Zeit. f.
WISH ZOOL. daw LOO, LOD. AA 15, elaine Ne,

3. Abs. do. in Anzerg. kats. Akad. wiss. Wien, Vol. VII,
1890, pp. 55-60.

ao trans. do: ine A Van ase Nol om uly, aps MOS:

5. Neue Beobachtungen tber Cypridinen. Zezt. f. wrss.
Z00ts, BC. XO, ppe 2 WI-277., spleens. 7,. 3)

6. Das Medien-auge der Crustaceen. Ard. Inst. Wren,
Bd EXS pp. 225-206; 4 Vat) 18091:

7. Ueber den feineren Bau des Medien-auges der Crusta-
ceen. Anz. Akad. Wien, p. 124-127, 1891. |

LANG.

8. Text-Book of Comparative Anatomy. Trans. by

Bernard, p. 344.

REHBERG, HERMANN.
g. Beitrage zur Naturgeschichte niederer Crustaceen. Brve-
men, 1884, p.. 11-13, Taf. II.
TurRNER, C. H.
10. Preliminary Note on the Nervous System of the Genus
Cypris. Jour. of Comp. Neur., Vol. Ill, 1893, pp. 35-
AO; pl Lil and liv:
VAVRA, WENZEL.
11. Monographie der Ostracoden Bohmens. rag, 1891,

Pp: 16-10; Mis, 14:

HISTORICAL RESUME.

Among the legions of histological monographs that recent
instruments and improved technique have called forth, those on
the neurology of the Ostracoda form an all but insignificant part.
To the best of my knowledge the first to write on this subject
was Leydig. He described the peculiar seta found on the sec-
ond joint of the antenna and called it a sensory seta.

Then followed Dr. Carl Claus, who, in 1860 (1) discussed
these same sete and called them ‘‘d/asse Kolben und Cylinder”’
or ‘‘ Leydische organe.”’ In 1865 (2) the same author discussed the
eyes of Cypridina, laying special stress upon a simple eye

22 JOURNAL OF COMPARATIVE NEUROLOGY.

which occurs in front of the paired eyes, because he thought
that the presence of that eye renders quite probable the
hypothesis that the compound eyes of the Cypride
are analogous to those of the Cladocera. According to
Dr. Claus this median simple eye consists of three layers; Ist,
an outer transparent lens; 2nd, an inner nervous layer ; 3rd, an
intermediate pigment layer. Both in form and position the
outer portion of this eye resembles the lens of the Heteropod eye.
The non-pigmented striated portion, into the substance of which
nerve fibres penetrate, contains elongated cells. Later Dr.
Claus (5) showed that in Cyfrzdina the size and position of the
paired eyes serve to differentiate the sexes. In the males, the
paired eyes are almost in the middle of the shell, while the much
larger, unpaired, median eye is imbedded ina swelling of the
forehead. In 1891, Dr. C. Claus (6) stated a theory concerning
the compound eyes of the Ostracoda.

Dr. Rehberg (g) also has contributed something to further
this cause. Among other things he has minutely and accurate-
ly described the tip of the second foot of Cyprts. In his eyes,
this member is something more than a leg functioning as an
ovipositor, for in its tip it bears a sensory organ which is proba-
bly auditory in function. In addition to this he has described,
in the following manner, the sensory seta found on the third .
joint of the antenna. This sensory seta consists of: Ist, a
chitin-surrounded proximal portion; 2nd, a short transparent
middle-piece ; 3rd, a granular knob-like distal portion. Its nerve
enters through a hole in the chitinous exoskeleton. ;

Later Dr. Lang (8) summarized the accessible literature
on the central nervous system of the Os¢racoda in the following
words: ‘‘ The ventral chain of Cythere, which follows the brain
and circum-oesophageal commissures, is said to consist of an in-
fra-oesophageal ganglion and four subsequent ventral ganglia.
The infra-oesophageal ganglion is said to show its composition out
of two ganglia and to innervate the jaws, while the three subse-
quent ganglia give off nerves to the limbs, and the last ganglion,
nerves to the most posterior divisions of the body and the genital
apparatus. In contrast with the above, the ventral chain of Ha/o-

Turner, Nervous System of Cyprts. 23
J S)

cypris appears much concentrated. It consists of an infra-oeso-
phageal ganglion, with nerves to the jaws and maxillipeds, and
a small ventral ganglion. Out of the latter arise two pairs of
nerves, which probably innervate the musculature of the limbs
and the abdomen.

Finally comes Wenzel Vavra who, in his late work (11), has
devoted three pages to the discussion of the nervous system of
the Ostracoda. In that work he makes the following statements:
Ist, the central nervous system consists of a brain and a five-
ganglionic ventral chain; 2nd, the optic and antennulary nerves
arise in the brain, but the antennary nerve arises in the pharyn-
geal collar ; 3rd, in the five-ganglionic ventral chain which extends
to the genital apparatus, the anterior three ganglia are closely
approximated; 4th, from each ganglion a nerve passes to a pair
of limbs and from the last ganglion a nerve passes to the genit-
al apparatus ; 5th, what Dr. Claus says about the structure of the
eye is correct; 6th, in Cyprza and Cyclocypris the eye is large
and the pigment black, in Cazdona the eye is inconspicuous and
the pigment reddish; 7th, in 7yphlocypris, although the eye of
the embryo is pigmented yet the eye of the adult is a degener-
ated, non-pigmented, sense organ; 8th, in Notodromas the three
eyes are separated, but each of the paired eyes is connected, by
means of a stalk, with the median eye, and each of these three
large eyes receives a distinct nerve from the brain; oth, the
sensory seta of the second antenna, which is longest in 7yphlo-
cypris, Candonopsts and Cyclocypris, is an olfactory organ; 10th,
the ‘‘blasse kolben”’ on the last segment of both the anten-
nules and antennae are composed of two segments; 11th, on
the fifth segment of the antenna of male and female specimens of
Notodromas there occurs a special sensory seta; 12th, in Can-
dona, Candonopsis, and Cypria the distal extremity of the
fourth segment of the male antennae bears a characteristic seta.

TECHNIQUE.

For hardening and fixing Ostracodes alcoholic picro-sul-

24 JOURNAL OF COMPARATIVE NEUROLOGY.

phuric has proven the best fluid. This fluid is compounded in
the following way:

70 per cent. alcohol. ; : ; 100 vols,

Sulphuric acid, conc. . : : : 2 vols.

Picric acid, as much as will dissolve.

For the above formula I am indebted to Dr. J. Playfair
McMurrich, now of Ann Arbor. Since this fluid sometimes
causes thin shells to curl, it is not so good for museum speci-
mens as 70 per cent. alcohol ; but for histological work it is ex-
cellent. It does not injure the tissues, it penetrates chitin easily,
and it fixes the cell structure. The living specimens were
placed in this fluid and allowed to remain for at least twenty-
four hours. Then after being washed in 70 per cent. alcohol
until all the picric acid had been removed, they were either
transferred to the stain or else, after being hardened and sec-
tioned in the usual way, they were stained on the slide.

Among the numerous stains tried were: Kleinenberg’s he-
matoxylin, Delafield’s hamatoxylin, Czokor’s alum cochineal,
borax catmine, eosin, etc., but none of these gave satisfactory
results. Finally Ehrlich’s hamatoxylin and tincture of alum
cochineal were tried. Both of these stains gave good results.
In using both of these stains the specimens were stained in toto.
When Ehrlich’s haematoxylin was used, the specimens were over-
stained and then washed out with acidulated 70 per cent. alco-
hol; but when the tincture of cochinea] was used, after remain-
ing in the stain for about twenty-four hours, the specimens were
washed in 70 per cent. alcohol and then hardened and sectioned
in the usual manner.

PRELIMINARY.

Although a lengthy discussion of the histology of extra-
neural systems would be foreign to the purpose of this paper,
yet, in order to facilitate a comprehensive description of the
nervous system, it is thought best to give a brief description of
the internal parts of the Ostracoda.

All previous writers to the contrary notwithstanding, the
shell of the Ostracoda consists of three layers: an ectal layer,

TurRNER, Wervous System of Cypris. 25

which has been hardened by the deposition in it of calcium car-
bonate; an ental, thin, flexible layer; and an intermediate layer
of connective tissue [fig. 1]. Where the shell is united to the
body the ental layer is absent [fig. 1, 6]. The connective tis-
sue in the shell is a continuation of the connective tissue of the
body. Most of the space between the ental and ectal layers
not occupied by the connective tissue, is filled by the gonads
and lateral evaginations of the mid-gut.

The body proper consists of two regions, a broad cepha-
lothorax anda narrower abdomen. The abdomen is movable
on the cephalothorax [fig. g]. Seven of the eight pairs of ap-
pendages arise from the cephalothorax, while the remaining pair
(the abdominal rami) arises from the caudal extremity of the
abdomen.

From near the dorsal extremity of the cephalic margin of
this creature arise the antennules and from a little below the
middle of the same margin arise the antennae. Passing caudad,
from the ventral margin arise, in quick succession, the mandibles,
Ist maxillae, 2nd maxillae, rst leg, 2nd leg.

The mouth, which lies between the mandibles, is bordered
by an unpaired upper and by paired lower lips. These, to-
gether with the mandibles, not only triturate the food, but serve
also as the locus of three pairs of sense organs [fig. 16]. The
short oesophagus, which is bordered with large cells [fig. gc],
extends almost vertically dorsad into the fore-stomach [fig. g].
In the walls of this grinding apparatus cells can be seen. Now
follows the stomach, from the walls of which lateral evaginations
project into the shell. The wall of this stomach is composed
of a single layer of columnar cells [fig. 37,41]. The dorsal por-
tion of the stomach is quite large, extending from the cephalic
extremity of the cephalothorax to the beginning of the abdo-
men [fig. 9,16]. The intestine extends through the abdomen
to the dorsally located anus, which is situated near the abdomi-
nal rami [fig. g].

The ovaries lie between the shell Jayers. After entering
the body on the dorsal side just caudad of the abdomen and
thence passing ventrad into the abdomen, the sexual ducts pass

26 JoURNAL OF COMPARATIVE NEUROLOGY.

ventro-meso-caudad to the median unpaired vagina, which lies
on the ventral side near the abdominal rami. The walls of the
abdominal portions of the sexual ducts are quite glandular.
They secrete the chorion of the egg.

Near the ventral side of the body there is a broad chitin-
ous exoskeleton [fig. 1,5], to which the muscles of the extrem-
ities are attached.

Surrounding all the organs of the body (nervous system
included) we find a mesenchyme-like connective tissue. This
connective tissue consists of membranous and fibrous cells,
among which are scattered larger and denser irregularly shaped
cells [fig. 1,11].

It is important that no one should suppose that the above
description is intended as an exhaustive histological study of
the Ostracoda. Although it contains some points that have not
yet been brought out by other investigators, nevertheless, it is
given merely to facilitate an intelligent description of the ner-
vous system and its relation to the extra-neural systems.

The Central Nervous System.

The central nervous system of Cyfris, like that of the
higher crustacea (J/alacostraca) is composed of a supra-oesoph-
ageal ganglion which is united by a pharyngeal collar to a multi-
ganglionic ventral chain. This is true, not only of Cyprzs, but
also of Cypridopsis, Cyclocypris and Candona. When we recall
that Dr. Lang states that in Cythere and Hfalocypris this is also
the case, we have grounds for believing that in all Ostracoda the
central nervous system consists of a supra-oesophageal ganglion
which is united to a ventral chain by a pharyngeal collar.

Supra-oesophageal ganglion.—This ganglion lies about half
way between the dorsal and ventral surfaces of the body and be-
tween the oesophagus and the cephalic border of the body. It
lies just below the place where the oesophagus enters the mid-
gut. In my preliminary paper the statement was made that
this ganglion was much nearer to the dorsal than to the ventral
surface. This was a misprint; the ganglion usually lies nearer
the ventral than the dorsal surface. This is a compound gan-

TuRNER, Wervous System of Cypris. 27,

glion. Although small, yet this supra-oesophageal ganglion is
probably compounded out of seven distinct ganglia. These
problematic ganglia are: three ganglia that have fused to form
the unpaired optic ganglion, two antennulary ganglia, and two
antennary ganglia.

The optic ganglion is located in the roof (dorso-cephalic
portion) of the supra-oesophageal ganglion. Although in the
adult it is a median unpaired structure, yet its histology seems
to indicate that it is a triune structure. The optic nerve arises
from the apex of this ganglion. In Cypvzs and the allied forms
examined by me, the optic nerve is a single unpaired nerve; but
in Votodromas, according to Wenzel Vavra, three optic nerves
arise from the brains The fact that in Motodromas three nerves
arise from the optic ganglion lends support to the view that this
is a triune ganglion. However, we must look to embryology
for a final settlement of this question, and the necessary data
are not at hand. Wenzel Vavra has called this portion of the
supraoesophageal ganglion from which the optic nerve arises the
fore-brain.

The paired antennulary ganglia occupy the lateral portion
of the supra-oesophageal ganglion [fig. 10]. Wenzel Vavra
has called this portion of this ganglion the mid-brain. From -
the dorsal portion of each side of this ganglion, arises a nerve.

Further ventrad, but nearer the meson, in the lateral por-
tion of the supra-oesophageal ganglion lie the paired antennary
ganglia [fig. 10]. A portion of this ganglion lies in the phar-
yngeal collar. Wenzel Vavra has called this portion of the gan-
glion the hind brain.

The supra-oesophageal ganglion is connected, by means of
a pair of circum-oesophageal commissures, with a sub-oesopha-
geal ganglion [fig. 16, 42]. These commissures pass obliquely
backwards and downwards (ventro-caudad) from the lateral por-
tion of the supra-oesophageal ganglion to the corresponding
portions of the sub-oesophageal ganglion. These two commis-
sures constitute the pharyngeal collar. This collar is not merely
a commissure but it is also the locus of a nerve centre. All along

28 JOURNAL OF COMPARATIVE NEUROLOGY.

its front (cephalic) border extends a chain of ganglionic cells.
The chain of cells is a portion of the antennary ganglion [fig. 3].

As in all invertebrate nervous systems, so here, the central
nervous system is composed of two things: nerve cells and

neuroglia (‘‘Punktsubstanz”’ of Leydig, ‘‘ Marksubstanz”’ of
Dietels and Rawitz, ‘‘ central Nervennetz’’ of Bellonci and

Haller). In the supra-oesophageal ganglia of Cyprts the nerve
cells are aggregated in the dorsal, cephalic, ventral and lateral
portions of the periphery, while the neuroglia is central.

Ventral Nerve Cord.—In his comparative anatomy, Pro-
fessor Lang has said: ‘‘ The ventral cord of Cythere which fol-
lows the brain and oesophageal commissures is said to consist of
an infra-oesophageal ganglion and four subsequent ventral gan-
glia. The infra-oesophageal ganglion is said to show its com-
position out of two ganglia and to innervate the jaws, while the
three subsequent ganglia give off nerves to the limbs, and the
last ganglion nerves to the most posterior division of the body
and genital apparatus. In contrast with the above, the ventral
chain of Hlalocypris appears much concentrated. It consists of
an infra-oesophageal ganglion, with nerves to the jaws and max-
illipeds, andasmall ventral ganglion. Out of the latter arise
two pairs of nerves, which probably innervate the musculature of
the limbs and abdomen.”’

Morphologically the ventral chain of Cypris is intermedi-
ate between these two extremes. It is more concentrated than
that of Cythere but not quite so compact as that of Halocypris.
In this case the ventral chain consists of an infra-oesophageal
ganglion and two subsequent ventral ganglia. All of these
nerve ganglia are connected, not only by two longitudinal com-
missures, but also by straggling chains of nerve cells [fig.
32,42]. To repeat, the ventral chain of Cypris is composed of
three pairs of ganglia, which are united by commissural fibres
and nerve cells.

Now Wenzel Vavra has recently stated that the ventral
caiuia of Cypris is conjosed of five ganglia. At first blush
these two views seem to be irreconcilable. However, when crit-
ically compared, the two views are not so antagonistic as they

TuRNER, Wervous System of Cypris. 29

seem. Dr. Wenzel Vavra confesses that ‘‘ Die ersten dret Gan-
glien stehen sehr gedrangt.’’ Although, in the adult the sub-
oesophageal ganglion of Cypris is an indivisible unit, yet my
investigations lead me to believe that it has been compounded
out of at least three pairs of distinct ganglia. Now if by say-
ing that the first three ganglia are closely compacted Wenzel
Vavra means that they are compacted sufficiently to form a tri-
une ganglion then our views harmonize.

From this compound ganglion arise the following five pairs
of nerves: nerve of the upper lip, mandibular nerve, nerve of
the lower lip, thoracic nerve.

The two halves of this ganglion are connected by three
transverse Commissures.

The first pair of ganglia behind (caudad of ) the sub-oesoph-
ageal ganglion gives off a pair of nerves to the second maxillae.

From the last ganglion arise two pairs of leg nerves and
one unpaired abdominal nerve.

In the region of the sub-oesophageal ganglion the ventral
chain lies above (dorsad of ) the endoskeleton, while back of that
region it lies below (ventrad of) the endoskeleton.

In the region of the sub-oesophageal ganglion the nerve
cells are confined to the ventral and lateral surfaces of the gan-
glion, while in the rest of the chain, the nerve cells occupy all
of the periphery and also the mesal plane.

Root gangla.—At the origin of certain nerves there is a
mass of ganglion cells. The ganglion is often quite intimately
united with the central nerve chain.

NERVES.

The principal nerves of Cyfris are: the optic, the anten-
nulary, the antennary, the labial, the mandibular, the labral,
the two maxillary nerves, the thoracic, the two leg nerves and
the abdominal nerve.

Optic Nerve.—The optic nerve arises from the apex of the
optic ganglion, which is also the apex of the brain. In Cypvis,
Cyprinotus and allied forms examined by me, this is a median
unpaired nerve. At a distance from the brain which varies

30 JOURNAL OF COMPARATIVE NEUROLOGY.

in different species, this nerve splits into three branches—one
for each of the divisions of the median tripartite eye. Passing
upwards (dorsad ) between the mid-gut and the cephalic border
of the body these branches pass to the compound eye, which
lies near the dorsal surface of the body. Indeed, this median
eye lies against the shell, vertically above the supra-oesopahgeal
ganglion | fig. 2, 9, 100, 420 |.

In Notodromas, according to Wenzel Vavra, there are three
optic nerves arising from the apex of the brain [ fig. 30]. Here
also we find that the three parts of the eye are widely separated
[ fig. 30]. It does not require a very active imagination to
conclude that simultaneously with the divarication of the com-
ponent parts of the triune eye there went a longitudinal tripar-
tite splitting of the entire optic nerve.

Antenaulary Nerves.—Vhe paired antennulary nerves arise
one from near each lateral surface of the apex of the supra-
oesophageal ganglion [fig. 10, 42]. After leaving this gan-
glion the nerve passes in a caudally convex curve upwards
(dorsad ), between the mid-gut and the cephalic border of the
body, to the corresponding ganglion. There is no root gan-
glion at the base of this nerve.

Antennary Nerves.—Where each circum-oesophageal com-
missure leaves the supra-oesophageal ganglion arises an anten-
nary nerve [ fig. 3]. This nerve receives its fibres, not only
from the brain, but also from a ganglion that extends in a strag-
gling manner along the pharyngeal collar | fig. 2, 8 ].

Labial Nerves. —The labial nerve or nerve of the upper
lip arises in the cephalic portion of the sub-oesophageal ganglion.
Instead of leaving the central nerve chain immediately, this
nerve passes upwards (cephalo-dorsad ) into the pharyngeal col-
lar and thence forward (cephalad ) to the upper lip [ fig. 3, 16,
42]. There is a large root ganglion at the origin of this nerve
[fig. 3]. The labial nerve has two main branches. One
branch innervates a pear-shaped sense organ situated in the
front part of the body below [ ventrad of | the base of the an-
tenna, while the other innervates a harp-shaped sense organ
located in the lower [ventral] portion of the upper lip [fig. 16].

TuRNER, WVervous System of Cypris. 31

Mandibular Nerves.—From each lateral portion of the sub-
oesophageal ganglion, just below (ventro-caudad of) the place
of fusion of the pharyngeal collar with this ganglion, a man-
dibular nerve leaves the nervous chain. Just after entering the
mandible this nerve branches, one branch passing upwards
(cephalo-dorsad ) to the mandibular muscles, while the other
passes downward (cephalo-ventrad ) to a sense organ at the
base of the mandibular teeth [ fig. 7 mx, 40 md]. There is
no root ganglion to this nerve.

Labral Nerves.—From each lateral portion of the ventral
aspect of this same ganglion, a short distance behind (caudad
of ) the origin of the mandibular nerve, arises a labral nerve.
Thence the nerve passes, in a caudally convex curve, downward
( ventrad ) to the lower lips [ fig. 32, 42 ]. The chief function
of this nerve is to innervate a harp-shaped sense organ located
in the lower lip [ fig. 16 D]. This nerve has a root ganglion.

first Maxillary Nerves.—A_ short distance caudad of the
origin of the mandibular nerve, a maxillary nerve leaves each
side of this same ganglion. This is the first maxillary nerve.
It passes latero-caudad to the first maxilla [fig. 7 mx”, 42].

Thoracic Nerves.—Al\\ of the four pairs of nerves just de-
scribed arise from the ventral side of the sub-oesophageal gan-
glion. Wenow come toa pair of nerves that arise from the
dorsal aspect of the same ganglion. These are what I beg per-
mission to call the thoracic nerves. These nerves arise from
the lateral portion of the dorsal aspect of this ganglion just
back of (caudad of) the origin of the first maxillary nerve.
Arising as it does from the dorsal aspect of the ventral chain,
the root of this nerve lies immediately beneath the endoskeleton.
This nerve passes obliquely upwards and backwards (dorso-latero-
caudad), and, after branching, innervates the abductor muscles
of the shell [fig. 327, 427].

To the best of the writer’s knowlege, neither this nerve nor
the labial nor the labral nerves have been described by any pre-
vious writer on the Ostracoda.

From the cephalic extremity of the ventral nerve chain to
the roots of the thoracic nerve the nerve cells are confined to

32 JouRNAL OF CoMPARATIVE NEUROLOGY.

the ventral and ventro-lateral surfaces of the cord. Behind
(caudad of ) the roots the nerve cells entirely surround the gan-
glia and occupy the mesal plane as well.

Within the ventral chain, beneath the origin of the thor-
acic nerves, there is a pair of ellipsoidal cavities. These might
properly be called thoracic ventricles.

Second Maxillary Nerves. —TVhis nerve arises from the lat-
eral aspect of the first ganglion behind (caudad of) the sub-
oesophageal ganglion.

Leg Nerves.—From the last ventral ganglion of Cypras
arise two paired nerves and one unpaired nerve. The paired
nerves innervate the legs, while the unpaired nerve passes into
the abdomen. The nerve of the first leg passes immediately
latero-ventrad to the first leg; but the nerve of the second leg
passes backwards (caudad) along with the abdominal nerve, a
short distance before passing to the second leg [fig. 42].

Abdominal Nerve.—As has been stated, from the caudal
portion of the last ventral ganglion a large unpaired median
nerve passes upwards and backward (dorso-caudad) into the ab-
domen. This is the abdominal nerve. After entering the ab-
domen, this nerve becomes more and more attenuated, owing
to the fact that it gives off fibres to the reproductive system
[fig. 32. an, 42 Ad].

The above descriptions of the principal nerves of Cyprzs do
not agree either with the descriptions of the few men who have
written on this subjects or with the statements made in my pre-
liminary paper. I cannot answer for the other men, but my
error was in mistaking the labial nerve for the mandibular nerve.
If you but recall the compactness of the anterior (cephalic) re-
gion of the body of Cyfrzs, you can see how easy it would be
to make such a mistake. However, I now have at hand sev-
eral series which demonstrate, beyond the shadow of a doubt,
that the nerves arise as stated in this paper.

No doubt it is this same compactness of the cephalic por-
tion of the body of Cypris which is responsible for the non-dis-
covery of the labial, labral, and thoracic nerves by other
observers.

TurNER, Nervous System of Cyprts. 33

Careful search has not yet revealed a sympathetic nervous

system.
Sense Organs.

Compound Eye.—The most conspicuous sense organ of the
genus Cypris is the compound eye. When viewed from above,
this eye usually resembles a quadrilateral pigment spot [fig. 36].
In Cyclocypris and Cypria, this eye is quite largeand the pigment
is intensely black; in Cypris and Cyprznotus, the eye is of medi-
um size ; in Candona, the eye is inconspicuous and the pigment
is reddish ; while in Zyphlocyprits, according to Wenzel Vavra,
there is no eye in the adult. The eye of the embryonic 7yphlo-
cypris, according to the same author, becomes metamorphosed
into an inconspicuous non-optical sense organ.

. This eye is a triune structure. It consists of a median and
two lateral portions, each of which is supplied with a lens
[fig. 2]. The lens of the median portion is on the front aspect
[fig. 36], while the lenses of the lateral portions are on the
sides [fig. 2, 36]. This median compound eye, which lies in
about the same vertical transverse plane as the supra-oesopha-
geal ganglion, is located where the dorsal border of the animal
is united to the dorsal portion of the shell. Hence there are two
planes, at right angles to each other, that pass through both the
compound eye and the supra-oesophageal ganglion. These
two planes are the mesal and a transverse plane.

Histologically there are five parts to this compound eye:
lens, retina, pigment, superficial epithelium, nerve [fig. 2].
Corresponding to each of the three divisions of the eye we
have a retina and a lens [fig. 2] anda nerve. The pigment is
deposited between and around the retina. The retinas are cell-
ular structures, the cells being arranged with their longest axis
perpendicular to the outer surface of the retina [fig. 2]. Each
retina is supplied with a lens, and these are always on the outer
surface. In the lateral portions these lenses are on the side,
while in the median the lens is on the front aspect [fig. 36].
The median portion lies lower than the lateral. Excepting the
central portions of the lenses, all of the surface of the eye, as
well as the space between the retinas, is pigmented [fig. 2, 36].

34 JOURNAL OF COMPARATIVE NEUROLOGY.

In Cypris herricki Turner the nerve fibres are united to the
outer (peripheral) ends of the retinal cells. This agrees with
what Dr. Claus found to be the state of things in the eyes of
the Copepoda, Clodocera and Ostracoda examined by him [7].

There is a striking resemblance between the triune eyes of
the Ostracoda and those of the Copepoda. In describing the
compound eye of Calanella mediterranea, Dr. Grenacher remarks
‘‘Each eye is composed of a pigment cup and a strongly re-
fractive transparent ‘lens’ laid in and on it. The term lens is,
however, not applicable. It is composed of several cells, each
of which is connected, whether at its outer or inner side is not
yet certain, with a fibre of the optic nerve, and must therefore
be considered asa retinal cell.’’ Since the superficial resem-
blance between the Ostvacod eye and the Copepod eye is so great,
one is apt to conclude that the above words of Dr. Grenacher
might be applied to the Ostvacod eye. Against such an assump-
tion I desire to enter a most emphatic protest. As stated above,
in the eye of Cypris we find both retinal cells and lenses, and
the two structures are histologically quite distinct. On the out-
side of the eye, covering lens and all, there is a nucleated epi-
thelial layer [fig. 2].

Since the publication of the paper’ in which O. Butschli
attempts to show how the lateral eyes of the vertebrates may
have been derived from the median tripartite eye of Sa/pa, this
tripartite eye, which is of almost universal occurrence among
the entomostraca, becomes enhanced in interest. One at once
begins to speculate on the possibility of this median triune eye
of the entomostraca becoming transformed into the lateral eyes
of the higher crustacea. Indeed, in his late work, Dr. Claus”
has already stated that the lateral eyes of the Corycxide are
laterally rotated portions of the median eyes. In this connec-
tion it may be of interest to quote a portion of Dr. Giesbeck’s

1 Rinige Bemerkungen ueber die Augen der Salpen, Zool. Anz., XV.,
Jahrg. 349.

2 Ueber die feineren Bau des Medianauges der Crustaceen. Anzeiger Akad.
Wien. 1891, pp. 124-127. Ref. in Zool. Jahrsbericht fiir 1891, Arthropoda, 29.

TURNER, WVervous System of Cypris. 35

resume of Dr. Claus’ paper: ‘‘ Die Sietenaugen der Coryceiden
sind abgedruckte Theile des Medienauges, diejenigen der Pon-
telliden entsprechen dagegen dem zusammengesetzten Arthro-
podenauge, wahrend ihr ventrales Auge ein dreitheliges Me-
dienauge dirfte ebenso wie die beiden frontalen Sinnesorgane
der ersten anlage nach auf Zellengruppen der Scheitelplatte,
vor deraus wir, . . die obern Schlundganglien der Glieder-
thiere abzuleiten haben, zu beziehen sein; die drei Augentheile
sind vielleicht mit den drei Punktaugen an der Scheitenplatte
von Annelidenlarven phylogenetisch in Beziehung zu bringen ;
die Lage ihrer Pigmentzellen und ihre inverse Form werden auf
eine convergent nach einem Punkte gerichtete Drehung zuriick-
gefuhrt, welche mit dem Herabriicken des Organs in die Tiefe
verbunden war; die Secret und Cornealinsen werden von Hypo-
dermiszellen abgeschieden, ahnlich wie Krystallkegel und Cor-
neafacette des zusammengesetzen auges; das auge besitzt eine
mesodermal Hille, die sich in das neurilemm des Opticus fort-
setzt ; Die function des Medienauges war ursprunlich das Thier
beztglich der Richtung der Lichtquelle zu orientiren; bei
compliciterem Bau, schon bei den Calaniden, hat es wahrschein-
lich auch die Fahigkeit einer beschrankten Bildperception. Am
Medianauge der Malakostraken-larven ist der ventral Becher
bisher incht beobdachtet, aber wohl auch vorhanden.”

A comparative study of the eyes of the Ostracoda lends
support to the view held by Dr. Claus. In Zyphlocypris there
is practically no eye, in Candona the triune eye is small and in-
conspicuous, in Cyp7zs it is somewhat larger, in Cyprza and Cyclo-
cyprts it is large and conspicuous, while in Votodromas the paired
portions of the compound eyes are so far separated that they look
like a pair of simple eyes united toa median eye by means of a
stalk [fig. 30].

Pear-shaped Sense Organs.—I\n the cephalic portion of the
body, a short distance above (dorsad of ) the upper lip, there is
a pair of peculiar pear-shaped sense organs [fig. 16, P]. To
the best of my knowledge this organ has been overlooked by
all other writers on the histology of Cyprzs. When viewed

36 JOURNAL OF COMPARATIVE NEUROLOGY.

from the side, this is a pear-shaped organ, with its base directed
outwards (ectad) and its apex inwards (entad).

In hematoxylin preparations, in the base of this pear-
shaped organ, there is a densely stained circular disc. In Cy-
prinotus tncongruens (Ramdohr) this disc is 12.92 micromillime-
ters in diameter [fig. 34].

The apex of this organ is surrounded by a ganglion of
nerve cells [fig. 34].

The length of this organ varies in different species. Ina
general way, the larger the species the larger this sense organ.
In Cyprinotus tncongruens Ramdohr, which is about 1.35 milli-
meters in length, this organ is 35.53 micromillimeters long and
32.3 micromillimeters wide ; while in Cyprzs herricki Turner,
which is about three millimeters in length, this organ is 71.06
micromillimeters long and 48.45 micromillimeters wide. In
other words, in Cypris herricki, which is about twice as long as
Cyprinotus incongruens, the pear-shaped sense organ is about
twice as long as the corresponding organ of Cyprdnotus tn-
conguens.

This organ is situated a short distance below the base of
the antenna and close to the outer wall of the body. The broad
base lies in contact with the body wall [fig. 16, P].

Since this organ is much larger in Cypris herricki Turner
than in any other form known to me, the following histological
study of the organ is based upon sections of that species.

From a histological standpoint, this pear-shaped organ is
composed of a neuroglia-like matrix, in which are two transverse
rows of nuclei. One of these rows of large nuclei is located
about half way between the base and the apex, while the other
row is situated near the apex. Near the base of this organ the
matrix is denser than it is elsewhere [fig. 31]. The organ is
surrounded by a nucleated epithelium.

This organ is innervated by a branch of the labial nerve
[fig. 16].

There is a pair of these organs, but they are so closely ap-
proximated that a hasty glance might not reveal both members
of the pair.

TuRNER, (Vervous System of Cypris. 37

As to the function of this organ, I have no definite proof;
but I am inclined to think that it functions as an eye. In
Cypridina, besides the usual compound eye, Dr. Claus has
described a median, unpaired simple eye. Now I am inclined to
think that this pear-shaped organ of Cyfrzs is homologous with
the unpaired simple eye of Cypridina. At first blush, there
are two facts that seem to militate against such an assumption
Ist, the median eye described by Claus is unpaired, while this
pear-shaped organ is distinctly paired; 2nd, the median eye
described by Dr. Claus is near to the compound eye, while this
pear-shaped organ is far removed from the compound eye. In
spite of these opposing facts, there are several weighty consid-
erations which lead me to hold to the statements made above.
Ist, Cypridina is much less compact than Cypris; 2nd, in
Cypridina the compound eye and the simple eye are situated
near the centre of the shell; 3rd, in Cyprzdina the parts of the
compound eye are widely separated, while in Cyprzs they are
closely approximated. May it not be that in the ancestors of
Cypris the compound and simple eyes lie near each other and
near the middle of the shell, as it now is in Cyprzdina ? May it
not be that when the compound eye migrated towards the
dorsal surface, the simple eye migrated towards the ventral ?
And when: we remember that in histology this pear-shaped
organ resembles the invertebrate simple eye, we have, I think,
sufficient grounds for calling this a simple eye. To be sure this
pear-shaped organ is one of a pair while the simple eye of
Cypridina is unpaired; but in this day, the phenomena of
transformations due to fission and to fusion are too well known for
this difference to merit even a passing consideration. The set-
tlement of this question, however, must be left to embryology.

Sense Organs of the Mouth.—In this same region of the
body, there is another set of hitherto undescribed sense organs.
From the caudal border of the upper lip, from the cephalic
border of the lower lip, and from between the teeth of the
mandible, arise numerous hairs [fig. 16]. These hairs are some-
times plumose [fig. 35]. At the base of each of these sets
of hairs there is a similar sense organ [fig. 16, B, C, D]. Each

38 JOURNAL OF COMPARATIVE NEUROLOGY.

of these organs is composed of oblong nucleated cells, which
are arranged with their longest axes perpendicular to the
hirsute surface [fig. 4]. The organs in the upper lip are
innervated by a branch of the labial nerve, those in the man-
dible by a branch of the mandibular nerve and those in the
lower lip, by the labral nerve [fig. 16]. Thus we have, sur-
rounding the mouth, three pairs of similar sense organs.

I have no definite proof as to the function of this set of
organs; but, since they surround the mouth, they probably
function as food discriminators. Whether this discriminating
sense is one of touch or taste I am not prepared to state.

Auditory Organ.—After describing rather minutely what
_ he considers to be a sense organ located at the tip of the second
foot, Dr. Rehberg expresses his belief that that organ is an ear.
Now I agree with Dr. Rehberg in believing that there is a sense
organ located in the tip of the second foot; but I think that its
function is not auditory but tactile. Ido not think that the
structure of the tip of the second foot warrants Dr. Rehberg’s
assumption. And beside, at the base each of the antennules I
have found what I consider the auditory organ of Cyprzs [fig. 16,
£]. This is an ellipsoidal body in the centre of which there is
a sac. The space between the outer wall of the ellipsoid and
the sac 1s occupied by a single layer of columnar cells. The
nuclei of these cells are located near the periphery. These cells
are best seen in transverse sections of the organ [fig. 33].
Often the cells contain large vacuoles [fig. 29]. Within the sac
there is a small spherical body which I take to be an otolith
[fig. 29]. Since in most of my preparations this sac has been
filled with a deposit of the stain used [fig. 33] I am not sure
that this spherical body that I find in other preparations is an
otolith or merely a bit of stain.

As to the innervation of this organ, I have no definite
knowledge. However, the antennary nerve is so intimately
associated with this organ [fig. 29a], that I am inclined to be-
lieve that that nerve innervates the auditory organ.

There are two patent facts that lead me to hold that this is
an auditory organ: Ist, in histology it resembles an otocyst ;

TuRNER, Wervous System of Cypris. 39

2nd, in location it resembles the auditory organ of the higher
crustacea (/alacostraca).

Olfactory Organs.—On the third joint of the antenna of all
the fresh-water Ostracoda, there exists a peculiar seta which all
writers have called an olfactory organ. As has been remarked
by other writers on this subject, this organ consists of the fol-
lowing three segments: basal piece, middle piece, end piece
[fig. 15]. In some cases the basal piece has been subdivided
into two pieces [fig. 17], while in others no middle piece can be
distinguished [fig. 14]. The nerve enters this organ through a
perforation in its base. Thence it extends along the axis of this
portion until it reaches the base of the middle-piece, where it
terminates in a small knob [fig. 15, 17]. In Cypres herricki
Turner this terminal knob is about three micromillimeters in
diameter.

The usual width of this organ is about three micro-milli-
meters. However, in Cyprza exculpta Fischer it is only about
two micromillimeters wide, while in Cyprzs herrickt Turner it is
about eight eight micromillimeters wide. In length the organ
varies from about 85 micromillimeters in Cypris herricki
Turner to about 29 micromillimeters in Cypria ineguivalva
Turner. In the same genera the length of the organ varies
directly with the length of the body of the specimen—the
longer the body the longer the organ. In those genera in
which the swiming setae of the antenna are greatly developed
(Cyclocypris, Cypria) this olfactory organ is relatively larger
than in those genera in which the natatory sete of the antenna
are more feebly developed (Cyprzs, Candona).

In the same species the tip of this organ may be either
blunt or pointed. Indeed, on one antenna of a specimen the
apex of this organ may be blunt, while on the other the tip
may be pointed.

The shape of this organ varies in different species. A
consultation of figures 12-15, 17-Ig and 21-22 will give a bet-

ter idea of these various shapes than could any number of
words.

40 JouRNAL oF CoMPARATIVE NEUROLOGY.

The following table has been compiled in order to facilitate
a comparative study of this olfactory organ:

P) 8) SES 5

4 : . 2lea|else| Ss

Table showing the relative size of Leydig’s = = é fas BS
organ ina few Cypride. = as ae) Po

6) 3)? 23]: »

TPL: Belts

NAME OF SPECIMEN. MICROMILLIMETERS

Candona acuminata (Fischer) Q ------------ 3 | 10] 20 | 43 |1250
Candona crogmani Turner 9, type ---------/ 19 6'| 23 | 48 |1520

BC ae Fe exception_.-.-. 16| —]| 19} 35
ee es i 6 ------------ 13| 6}| 26] 45 |1520
Candona delawarensis Turner, Q ---------- 10} 3] 23] 36] 950
GC ss + $ ----------- 14| 5] 20] 39

Candona fabeformis (Fischer) Q ------------ 12] 6)| 19 | 37 {1030
Cyclocypris levis (O. F. Muller) Sasa ee aa 29] 6] 32|67]| 570
Cypria exculpta (Fischer) ------------------- 23! 3116] 42] 640
Cypria ineguivalva Turner, 9 ---------- ---- 13/10] 6] 29] 520
Cypria ophthalmica (Jurine) ----------------- Io | 10| 16] 36] 580
Cypridopsis vidua (O. F. Miiller)------------ 19 | —]| 16] 35] 700
Cyprinotus burlingtonensis, Turner, 9 --.---- 26 | 10 | 29 | 65 |1600
Cyprinotus crena, Turner, 9 ---~----------- 19| 8| 23] 40/1230
Cyprinotus incongruens (Ramdohr) ---------- 39| 6116] 61/1350
Cypris fuscata (Fischer) ------ ues ples 2 eee 36| 7 | 20] 63 |1500
Cypress therrickt, Wunders? eae a ee 2| 4149 | 85 |3000

Sensory Sete.—In addition to tne sense organs already de-
scribed there are several types of sensory sete that deserve at
least a passing notice. Not having been able to trace a nerve
into any of these sete, I have given but a brief notice of them.

At the tip of the antennules and antennae of all the
Cypride there occurs a two-segmented sensory seta [fig. 20].
This seta is longest in Zaphlocypris, where it is as long as the
terminal claw. In Condona fabeformis Fischer this seta is 48
micromillimeters long. In this case, the terminal segment is
ten micromillimeters long. | Owing to its small size and to the
number and size of the associated claws and filaments, this
organ is a very difficult object to study.

At the extremity of the fourth segment of the antenna of
Notodromas there is a peculiar seta with a funnel-shaped tip
[fig. 28].

At the tip of the fourth segment of the antenna of the male
members of the genera Candona, Candonopsts and Cypris there
is a peculiar two-jointed seta [fig. 24-27]. Dr. Wenzel Vavra

TurRNER, Wervous System of Cypris. 4!

considers this a rudimentary organ. Its morphology varies in
different species. By Dr. Wenzel Vavra the variations that we
meet with in this organ are considered to be of taxonomic value.

On the tip of the third and fourth segments of the mandi-
bular palp of certain Cyprzd@, there occurs a short dagger-
shaped setose seta [fig. 23 D.S.]. This seta was first described

) 2 ohis 'setanOCcurs ime:

in the ‘‘ Entomostraca of Minnesota.
Candona crogmant Turner, Candona delawarensis Turner, Cyprt-
dopsis vidua O. F. Miller, Cyprzs herrickt Turner, Cyprinotus

burling tonensts Turner.
Recapitulation.

1. The nervous system of Cyprzs consists of a supra-
oesophageal ganglion, which is connected to a ventral chain by
a pharyngeal collar.

2. The ventral chain consists of an infra-oesophageal and
two subsequent ganglia. The infra-oesophageal ganglion has
probably been compounded out of at least three pairs of ganglia.

3. From the supra-oesophageal ganglion arise one un-
paired and two paired nerves. These nerves are: the optic,
the antennulary, the antennary. The antennary nerve receives
a portion of its fibres from a ganglion that lies within the phar-
yngeal collar. The nerve itself arises from the point where
the collar joins the supra-oesophageal ganglion.

4. From the infra-oesophageal ganglion arise five pairs of
nerves. Four of these pairs arise from the ventral portion of
the ganglion, while the other arises from the dorsal. The four
that arise from the ventral half are: the labial, the mandibular,
the labral, and the first maxillary. The one that arises from the
dorsal portion is the thoracic nerve.

5. The labial nerve passes forward into the pharyngeal
collar before leaving the central nerve chain.

6. The thoracic nerve innervates the shell muscles.

1C, L. Herrick and C. H. Turner. Synopsis of the Entomostraca of
Minnesota with descriptions of related species comprising all known forms from
the United States included in the orders Copepoda, Cladocera, Ostracoda. St.
Paul, Minn., 1895.

42 JOURNAL OF COMPARATIVE NEUROLOGY.

7. The 2nd maxillary nerve arises from the first ganglion
back of the infra-oesophageal ganglion.

8. From the last thoracic ganglion arise one unpaired and
two paired nerves. The paired nerves are the leg nerves; the
unpaired nerve is the abdominal nerve. The abdominal nerve
innervates the genital apparatus.

g. There is a median compound triune eye. The eye is
situated near the dorsal surface. Each of the three divisions
of this eye is supplied with retinal cells and alens. The nerve
enters the outer ends of the retinal cells. In most of the fresh-
water Cyprid@ the component parts of this eye are closely ap-
proximated. In Wotodromas, on the contrary, the three parts
are widely separated.

10. In most of the fresh-water Cyprzd@ the optic nerve
is a median unpaired structure, which splits into three branches.
In Notodromas, however, there are three distinct optic nerves.

11. Inthe front part of the body, between the base of
the antennae and the upper lip, there is a pair of pear-shaped
sensory organs. These are probably simple eyes. This organ
is innervated by a branch of the labial nerve.

12. At the base of the antennule there is an auditory
organ.

13. Bordering the mouth there are three pairs of similar
sense organs. These organs lie in the upper lip, at the base of
the mandibular teeth, and in the lower lip. They are innervated
by branches of the following nerves: labial, mandibular, and
labral.

14. On the third segment of the second antenna there is
the so-called olfactory organ. This organ consists of three seg-
ments; the basal, the middle, and the end piece. The nerve
enters the basal portion and extends to the base of the middle
piece, where it terminates in a knob-like swelling.

15. In addition to the above sense organs there are sev-
eral types of sensory setae.

TURNER, Vervous System of Cypris. 43

EXPLANATION OF PLATES.

Excepting where otherwise stated, the plates were all made from camera
drawings made by the writer.

PEATE TIT:

Fig. 1. Cypris herricki Turner, transverse section of body in the region
of the posterior portion of the mid-gut. A, endoskeleton; n, nerve chain.

fig. 2. Do., do., transverse section of median eye.

Fig. 3. Do., do., longitudinal section of circum-oesophageal commissure.
a’, antennary nerve; md, mandibular nerve.

fig. 4. Do., do., transverse section of the sense organ of lower lip.

fig. 5. Transverse section of the endoskeleton.

fig. 6. Do., do., transverse section of the body in the region of the lat-
era] diverticles of the mid-gut.

PLATE IV.

Fig. 7. Cypris herricki Turner, longitudinal section through the sub-
oesophageal ganglion. Mx’, mandibular nerve; mx’, Ist maxillary nerve.

fig. 8. Do., do., longitudinal section through the brain at the level of the
origin of the circum-oesophageal commissures, A’, antennary nerve.

fig. 9. Do., do., median longitudinal section of the entire body. S.g.,
brain; A, harp-shaped sense organ of the lower lip; B, ventral nerve chain;
C, cells in wall of oesophagus.

fig.1o. Do., do., transverse section through the brain, in the region of
the optic and antennulary nerves.

Fig. 11. Do., do., longitudinal section of a portion of the ventral chain.

PLATE V.

Fig. 12. Candona delawarensts Turner, olfactory seta from the third joint
of the antenna.

Fig. 13. Candona facbformis (Fischer), do., do.

Fig. 14. Cypridopsis vidua (O. F. Miiller), do., do.

Fig. 15. Cypris herrickt, Turner, do., do.

fig. 16. Cypris herricki Turner, longitudinal section through the body.
A.N., antennulary nerve; B, harp-shaped sense organ of the upper lip; C, harp-
shaped sense organ at the base of the mandibular teeth; D, harp-shaped sense
organ in the lower lip; E, auditory organ; L.N., labial nerve; P, pear-shaped
sense organ of the upper lip; S.G., supra-oesophageal ganglion.

Fig. 17. Cypris fuscata Jurine, olfactory seta from the third joint of the
antenna.

fig. 18. Cyclocypris laevis (0. F. Miiller), do.

fig. 19. Cypria exculpta (Fischer), do. ,

Fig. 20. Candona fabeformis (Fischer), sensory seta from tip of first
antenna.

Fig. 21. Cypria ophthalmica (Jurine), sensory seta from third joint of
antenna.

fig. 22. Cyclocypris laevis (O. F. Miiller), do., do.

44 JoURNAL OF COMPARATIVE NEUROLOGY.

PLATE VI.

Fig. 23. Cypris herricki Turner, mandibular palp. D.S., dagger-shaped
seta.

Fig. 24. Candonopsis pubescens, sensory seta from the four segments of the
antenna of the male.

Fig. 25. Condonopsis kingslet, do.

Fig. 26. Candona fabeformis, do.

Fig. 27. Candona candida, do.

Fig. 28. Notodromas monacha, Sensory seta from the fifth segment of the
antenna.

Figures 24-28 have been copied from Wenzel Vavra.

PLATE VII.

Fig. 29. Cypris herricki Turner, auditory organ from a longitudinal per-
pendicular section. A. antennulary nerve; m, muscle.

fig. 30. Natodromas monacha, eyes (after Vavra).

Fig. 31. Cypris herricki Turner, pear-shaped organ of the upper lip, sec-
tional view. ;

Fig. 32. Cyprinotus incongruens (Ramdohr), ventral chain. A, antennary
nerve; A N, abdominal nerve; L, labial nerve; L’, branch of same to pear—
shaped organ; L’’, branch of same to harp-shaped organ; La, labrum.

Fig. 33. Cypris herricki, Turner, auditory organ, from a horizontal-longi-
tudinal section.

Fig. 34. Cyprinotus incongruens (Ramdohr), pear-shaped sense organ of
upper lip, surface view.

Fig. 35. Cypris herricki Turner, tip of mandible showing hairs that be-
long to the sensory organ found in the mandible.

Fig. 36. Cypris pubera, eye, surface view (after Wenzel Vavra).

PLATE VIII.

Fig. 37. Cypris herricki, Turner, wall of mid-gut.

Fig. 38. Cypris herrickt, Turner, tip of second foot.

Fig. 39. LDo., do.,wall of oesophagus.

Fig. 40. Cyprinotus incongruens (Ramdohr), transverse section through
the mandibular nerve. S, sub-oesophageal ganglion ; md, mandibular nerve.

Fig. 41. Cypris herricki Turner, surface view of wall of mid-gut.

fig. 42. Diagram of the central nervous system of Cyfrzs. A, atennu-
lary nerve; Ab, abdominal nerve; At, antennary nerve; L, labial nerve; L’,
branch of labial nerve passing to the pear-shaped sense organ; L’’, branch of
labial nerve passing to the harp-shaped sense organ; Lb, labral nerve; Lg’, Ist
leg nerve; Lg’’, second leg nerve ; Md, mandibular nerve; Mx’, Ist maxillary
nerve; Mx’, second maxillary nerve; T, thoracic nerve; T. V., thoracic
ventricle.

Fig. 43. Nerve cell of Cypris.

PRELIMINARY NOTES ON THE CRANIAL NERVES
OF CRYPTOBRANCHUS ALLEGHANIENSIS.

J He MeGrEcor;, )B-Se;,

University Fellow in Biology, Columbia University.

The present communication is by no means a complete
description of the cranial nerves of Cryptobranchus, but is merely
a somewhat cursory sketch of the distribution of most of the
more important rami. It was the hope of the writer to have
completed before this time a study of the brain and cranial
nerves of this amphibian, working out the nerve components
from serial sections, but the difficulty in obtaining embryonic
material for sectioning has so delayed the work that it has been
thought best to present a brief preliminary account based almost
entirely upon dissections of adult animals.

Recent researches on cranial nerve components render it
possible to determine, even by dissection, some points of im-
portance in nerve homologies, though, of course, reconstruction
from sections will be necessary to ascertain the more intimate re-
lations of the components.

In general, no attempt has been made in the present paper
to trace the relations between nerve-roots and the ultimate rami.
So far as possible the writer has endeavored to indicate homol-
ogies with other amphibians, basing the comparisons mainly
upon recent investigations on Rana, Amblystoma and
Salamandra.

Nervus olfactorius.—This nerve is somewhat peculiar in
Cryptobranchus from the fact that it divides into numerous
branches before leaving the cranial cavity. Within the cranium
these branches extend cephalad in two large bundles on each»
side, giving each olfactory nerve the appearance of being
double.

46 JOURNAL OF COMPARATIVE NEUROLOGY.

Nervus opticus.—The optic is very similar to that of uro-
deles in general. There is a slight vestige of a lumen at the
base of the nerve.

The nerves of the eye-muscles are all present but very
small. The oculomotor is the largest of the three and maintains
an independent course throughout its whole extent, leaving the
cranium by a special foramen slightly caudad of the optic fora-
men. In part of its course this nerve lies very close to ramus
ophthalmicus profundus of the fifth. The courses of the sroch-
learis and abducens have not been determined. They are both
extremely minute, as would be supposed from the very degen-
erate condition of the eye-muscles. The point of origin of the
abducens appears to be somewhat variable. It has been figured
by Osborn as leaving the medulla on a level with the fifth
nerve, but transverse sections prepared by the writer show the
abducens taking its exit on a level with the cephalic roots of the
glossopharyngeo-vagus complex as it does in Rana, Diemctylus,
Salamandra, Amblystoma and other forms.

Nervus trigeminus.—The distribution of the fifth nerve in
Cryptobranchus has been described by Fischer and more re-
cently by H. H. Wilder, though neither of these writers has
given a complete description. The first ramus, the ~ ophthal-
micus profundus, after leaving the ganglion, traverses a canal in
the pterygoid bone, coming to the surface some distance cepha-
lad of the other two rami. It trends cephalad, passing mesad
of the eye-ball and dorsad of the optic nerve and all the eye
muscles except the superior oblique and superior rectus. “The
greater part of the ramus passes cephalad to a point cephalad
of the eye, where it breaks up into numerous branches anasto-
mosing with branches of the superior maxillary ramus. The
nerve thus formed enters a groove in the superior maxillary
bone and sends branches to the skin of the upper lip through
three or four foramina anda small notch in the lateral border of
the anterior nares. This branch has been called by Wilder
ramus nasalts externus.

The two branches to the nasal capsule have been well de-
scribed by Wilder who designates the ventral and dorsal

McGreoor, Cranial Nerves of Cryptobranchus. 47

branches respectively as vamus nasalis externus I and ramus
nasalts externus II, The former, as shown by Wilder, receives
a branch from the ramus maxillaris V.

In addition to the branches already described there is a
small branch entering the eye-ball which is probably to be re-
garded as the ciliary nerve, and another small branch which is
traceable to the region of the antorbital fissure in the nasal
capsule. The latter branch is probably distributed to the glands
of the nasal region, but a study of serial sections will be neces-
sary to settle this point.

The ramus maxillaris supertoris of the Trigeminus breaks
up into several branches immediately upon leaving the cranium.
It runs dorsad of the masseter muscle then dips ventrad of the
eye supplying numerous branches to the skin of the upper lip
and anatomosing with the ramus nasalis externus of the deep
ophthalmic. A branch also runs along the floor of the nasal
capsule as described in connection with the ramus ophthalmicus
profundus. The ramus maxillaris superioris is accompanied for
some distance by the ramus ophthalmicus superficialis of the
facial nerve, and the two are described together by Herrick in
Amblystoma as ramus fronto-maxillaris. Though the two nerves
run close together for a part of their course, they are separate
as far back as the ganglion Gasseri. It is almost certain that
one of the branches which appears to belong to the superior
maxillary ramus represents the ramus buccalis VII (in the
sense in which this name is used by Strong and the writers on
fishes). This view is supported by the presence of well-devel-
oped lateral line organs between the eye and the angle of the
mouth, the so-called infra-orbital sense organs.

The ramus mandibularis V is larger than either of the
other two rami. At its point of exit from the skull it gives a
small branch to m. temporalis, then, trending laterad, it pierces
m. masseter to which it contributes several twigs. At about
the middle of its course through m. masseter a fairly stout
branch separates from the main ramus and runs latero-caudad
passing through a slight notch under the lateral border of the
squamosal bone. This branch sends a number of twigs ceph-

48 THE JOURNAL OF COMPARATIVE NEUROLOGY.

alad, supplying the skin covering m. masseter and the region
of the angle of the jaw; it is evidently a general cutaneous
branch and may represent Strong’s vamus accessorius V. The
greater part of samus mandibularis V enters the inferior maxil-
lary by a large foramen about one-third the length of the bone
from the proximal end. Just before its entrance into the man-
dible it divides into two branches, the caudal of which passes
directly through the mandible, appearing on the ventral border
almost opposite the point of entrance. The foramen of exit
is included between the splenial and angular bones. This por-
tion of the nerve innervates m. mylohyoideus anterior, and is
traceable almost to the symphysis menti, breaking up into sev-
eral branches on the ventral surface of the muscle. C. J. Her-
rick finds this branch to contain sensory fibres in Amblystoma,
and the same is probably true in the case of Cryptobranchus.
The branch in question is called vamus mentalis by von Plessen
_and Rabinovicz, but, as Herrick states, the name is more prop-
erly applied to the ramus we shall next describe.

The ramus mentalis V is the cephalic one of the two
branches which enter the mandible. It divides almost imme-
diately into two branches which are separated by the Meckelian
cartilage ; the ental branch is the dental nerve and supples the
alveolar region; the other, a larger branch, lies ectad of the
Meckelian cartilege and traverses a canal in the dentary bone.
Shortly beyond its point of separation from the inner branch it
is joined by the ramus alveolaris VII, which enters a foramen
in the ectal surface of the dentary bone. The fibres of the two
nerves mingle and pass cephalad through the canal above men-
tioned, extending almost to the symphysis menti and giving off
some half-dozen clusters of small branches which pierce the
ectal surface of the dentary bone at intervals and supply the
skin of that region. It is not certain as yet whether these fibres
to the skin belong to the ramus mentalis V or to the ramus
alveolaris VII.

Nervus Facialis.—The seventh nerve of Cryptobranchus
does not exhibit any very important variations from the con-
dition generally found in urodeles. In correlation to the well-

McGrecor, Cranial Nerves of Cryptobranchus. 49

marked lateral line sense-organs, we find the rami of the dorsal
VII root, or VIIb. of Strong, well developed. The fibres of
the Rr. ophthalmicus super fictalis and buccalis are very probably,
judging from analogy with the frog larva, contained in a large
root (VII wand / of Osborn) which enters the caudal border of
the Gasserian ganglion. These two rami leave the ganglion in
company with ramus maxillaris superioris passing with it dorsad
of m. temporalis. Ramus ophthalmicus superficiais VIT runs
cephalad to the nostril, innervating the supra-orbital sense-organs
of the lateral line system. This ramus seems to have been en-
tirely overlooked by Fischer, and several recent writers have
called it ramus frontalis V. Its community of origin with other
lateral line rami, as shown by Strong, and its distribution to
the region of the supra-orbital line of sense-organs leaves no
doubt as to its true nature. Ramus buccalis VII accompanies
ramus maxillaris superiorts V as far as the eye and ends in the
infra-orbital sense-organs. This is not the homologue of the
ramus buccalts as described by von Plessen and Rabinovicz and
by C. J. Herrick, but the ramus maxillaris V of these writers
no doubt includes the ramus buccalis as the name is here used.
The root marked d in the figures of Salamandra given by von
Plessen and Rabinovicz and of Amblystoma by Herrick is prob-
ably homologous with the VII w and / of Crytobranchus as fig-
ured by Osborn and probably contains the fibres of the two
lateral line rami here described.

Besides the two rami of the VII already described there
are four others, all of which were described by Fischer, who
called them Rr. palatinus, mentalis, alveolaris and jugularts.
Ramus palatinus is rather small; it passes ventrad through a
foramen in the prootic ossification and is covered ventrally for
some distance by the very broad parasphenoid bone. Near the
level of the posterior nares it forms anastomoses with Rr. oph-
thalmicus profundus V and maxillaris superioris V. Onaccount
of its anastomoses the ultimate distribution of the facialis fibres
can be determined only by serial sections through the head.
The vamus alveolaris of Fischer runs laterad along the dorsal
surface of the squamosal bone, then cephalad between m. masse-

50 THE JOURNAL OF COMPARATIVE NEUROLOGY.

ter and the skin, and enters a foramen in the lateral aspect of
the dentary bone cephalad of the area of insertion of m, masse-
ter. Within the bone it unites with a branch of ramus men-
talis V, and pursues its course almost to the symphysis menti,
supplying branches to the lower lip, through some six or eight
foramina in the dentary bone. As stated in connection with
ramus mentalis V, it is not certain which component supplies
the fibres to the skin of the lower lip. It appears to me not
improbable that thisramus alveolaris VII may correspond to the
ramus mandibularis tnternus VII described by Strong in the tad-
pole, and may therefore represent the chorda tympant. The
dentary being a dermal bone, the nerve may have secondarily
become covered by it. I have not been able to find all the
branches described by von Plessen and Rabinovicz and by Her-
rick in Salamandra and Amblystoma respectively. The ramus
in question must be represented by the alveolaris, accessory
hyo-mandibularis or buccalis of Salamandra and Amblystoma,
in the sense in which Herrick and v. Plessen and Rabinovicz use
these names. Herrick thinks, perhaps with good reason, that
the hyo-mandibular ramus of Amblystoma is the homologue of
Strong’s chorda tympani or ramus mandibularis internus. If
my supposition regarding the homologies is correct, the latter
name is preferable to vamus alveolarts. Fischer's ramus mentalis
is really the lateral line ramus to the lower jaw and therefore
the branch which Strong designates as vamus mandibularis ex-
ternus in the tadpole. In Cryptobranchus this branch does not
accompany the hyo-mandibular as in the frog, but is a separate
ramus as far back as the ganglion. It ccurses laterad along the
dorsal face of the squamosal bone, passes ventrad of the man-
dible and cephalad along the ventral surface of the mylohyoid
muscles close to the mandible, dividing into two branches which
supply the gular and oral lines of lateral line sense-organs.

The fourth branch mentioned by Fischer as ramus jugularts,
is the rsamus hyo-mandibularis of later writers. As in other
amphibians it receives the vamus communicans IX ad VII.
The ramus hyo-mandibularis in Cyptobranchus does not contain
all the elements demonstrated by Strong in the nerve of that

McGreoor, Cranial Nerves of Cryptobranchus. 51

name in the frog, since, as indicated above, the ramus mandibu-
larts externus and ramus mandibularis internus are separate rami
as far back as the facialis ganglion. Ramus hyo-mandibularis
pierces the cephalic division of m. depressor maxillae inferioris
to which it gives several small twigs, then trends ventrad break-
ing up into numerous small branches in m. mylohyoideus pos-
terior. The ramus is thus in the main motor but a few sensory
branches pass to the skin over m. depressor maxillae inferioris,
and probably there are sensory branches to the skin under the
jaw. Strong has shown that in the frog these sensory fibres are
derived from the ramus communicans IX ad VII.

Nervus acusticus. The auditory nerve of Cryptobranchus
has the usual close relation to the facial. Its distribution is
beautifully described and figured by Retzius in Vol. I of Das
Gehororgan der Wirbelthiere.

Nervus glossopharyngeus. The most cephalic branch of the
glossopharyngeus is ramus communicans [IX ad VII. This ramus
trends latero-cephalad and unites with the ramus hyo-mandibu-
laris at about the point of entrance of the latter into m. de-
pressor maxillae inferioris. The next division consists of sev-
eral slender branches passing dorsad to the skin on the dorsal
surface. Since this division innervates the region of the occip-
ital group of lateral-line sense-organs there is a possibility that
it represents the ramus supratemporals of Strong.

The ramus immediately caudad of the preceding is a slen-
der branch which passes ventrad to the mucous membrane of the
roof of the pharynx. It can be traced cephalad as far as the
post-nasal process, lying close to a blood-vessel between the
pterygoid bone and the mucous membrane of the roof of the
mouth. Herrick finds a somewhat similar ramus in Am-
blystoma which anastomoses with the ramus palatinus VII.
This ramus seems to be the ramus pharyngeus of Fischer.

The vamus linguals lies furthest caudad and is much the
largest of the glossopharyngeus branches. After passing latero-
caudad over the hyo-suspensorial ligament it gives off a slender
cutaneous branch, which anastomoses with a somewhat similar
branch of the vagus, supplying the skin cephalad of the branch-

52 JOURNAL OF COMPARATIVE NEUROLOGY.

ial cleft. After giving off the cutaneous branch the ramus en-
ters m. hyobranchialis to which it gives a motor branch, then,
emerging from the muscle, it passes dorsad of the hypo-hyal
cartilage and enters the tongue, near its cephalad border. Oc-
casionally the r. lingualis merely lies on the ventral surface of
m. hyo-branchialis, only the motor branch penetrating the mus-
cle. Thus the ramus generally called lingualis is a mixed
nerve.

Nervus vagus. As my study of the vagus is not yet as
complete as it is possible to make it even by gross dissection, I
shall not attempt a description of all its rami.

The most cephalic branch gives fibres to the skin cephalad
of the branchial cleft and anastomoses with the branch of the
glossopharyngeus which innervates the same region. There is
also a small motor branch running cephalad to m. constrictor
arcuum branchialium, and to the caudal part of m. genio-cerat-
oideus. Another slender branch passes to m. levator arcuum
branchialium and to the skin caudad of the branchial cleft.

The largest ramus includes the ramus visceralis and a large
recurrent branch. This latter branch is the one figured by
Fischer as the hypoglossal nerve, and he was probably at least
partially correct, as this nerve receives an anastomosing branch
not only from the first but also from the second and third spi-.
nal nerves. The greater part of the fibres of this nerve are,
however, plainly derived from the vagus. and probably repre-
sent a ramus recurrens vagt. It gives branches to m. constrictor
pharyngeus, m. depressor arcus branchialis posterioris and m. dor-
so-laryngeus, then runs cephalad and appears to end in m. genio-
hyoideus. A branch to m. sterno-hyoideus is also derived
from some part of this vago-hypoglossal complex. The most
caudal ramus of the vagus is a lateral line branch.

The first spinal nerve has no dorsal root, its origin is almost
at the level of the foramen magnum, and it takes its exit by a
foramen in the first vertebra. It gives several small branches
to the m. longissimus dorsi of the neck region, but the largest
ramusis that which anastomoses with the ramus recurrens of the
vagus. There are also anastomosing branches which unite this

McGreoor, Cranial Nerves of Cryptobranchus. 53

branch of the first spinal with the second and third spinal
nerves. The last two have dorsal roots, and the third takes
part in forming the brachial plexus. Communication between
vagus and hypoglossus has been discovered in larval Anura but
it has not been described, so far as 1 am aware, in Urodela.
Most of the material at my disposal was injured in the neck re-
gion so that the relations of these parts could not be clearly
ascertained. Many points regarding the intimate relations of
vagus and hypoglossal nerves will require a study of serial
sections for their elucidation.

ON THREE POINTS: IN THE NERVOUS ANATOR
OF AMPHIBIANS.

J. S. Kunecstey.
With three figures.

In my studies of the head of Amphiuma, which I hope to
have completed at an early date, I have found it necessary to
make comparisons with the results of other observers, and in
some cases to repeat their observations, especially in those cases
where Amphiuma presented features not easily reconciled with
the conditions existing in other foms.

For this purpose I have had to go over the results ob-
tained by von Plessen and Rabinowicz in their classic ‘‘ Die

d

Kopfnerven von Salamandra maculata.” Studying latvae of
this species, varying between two and a half and three centi-
metres in length, these authors figure and describe a commis-
sure as existing between the ramus palatinus of the facial and
their supra-maxillaris superior of the trigeminal, a condition
which is not easily reconcilable with what I find in Amphiuma
nor with what other authors find to exist in the Urodeles. To
test the question as to whether Salamandra maculata was unique
in this respect I sectioned a larva of twenty six millimeters
and plotted the sections in the same manner as these authors
did. As awhole I can confirm their results, but there are a
few features which need correction. In their figures they give
a small nerve, designated by the letter z, forming a ramus com-
municans between the mandibularis and the maxillary (their
supra-maxillaris superior) nerves. In my studies this ramus
communicans also occurs, but, instead of its being very small it
is fully as large as the branch from the ‘‘nebenganglien”’ with
which it connects. Detailed study of many Urodeles shows
that the maxillaris must be regarded as a compound nerve,
with both facial and trigeminal components. See fig. 1.

KincsLey, Nervous Anatomy of Amplibrans. 55

Still further in front von Plessen and Rabinowicz describe
a nerve uniting the maxillaris with the palatine. As sucha
ramus communicans occurs in no other Urodele which I have

Figure 1. Wateral reconstruction of the proximal portions of the fifth and
seventh nerves of a Salamandra maculata embryo, body length 26mm. ag,
accessory ganglion of VII; g/, ganglion of facialis; gg, Gasserian ganglion ;
md, ramus mandibularis ; mx, ramus maxillaris; of, ophthalmicus profundus ;
os, ophthalmicus superficialis; vos, root of the ophthalmicus profundus; 7Vv,
root of the trigeminal; vi, root of the facialis; *, ramus communicans be-
tween the mandibularis and maxillaris nerves. x 30.

studied, this condition was also investigated. In all other Uro-
deles the connection occurs between the opthalmicus profundus
(the nasalis of von Plessen and Rabinowicz) and the palatine, a
condition which is not found in their figures or description. In
this I think they have made a mistake and that a part of their
error has arisen in this manner. In Salamandra, near the an-
terior limit of the eye the maxillaris nerve comes to lie close
against the inferior oblique muscle at its insertion on the ball
while the middle branch (their 0) of the ophthalmicus pro-
fundus lies against the same muscle near its origin. It there-
fore appears possible that they have mistaken the muscle fora
part of the ramus communicans, a mistake the more readily
made since in many forms there is such connection between the
maxillaris and the palatine. The true relationship may be seen
from fig. 2, which shows the middle division of the ophthal-
micus profundus connected with the palatine by a short
transverse commissure, just as is the case in Amblystoma,
(my studies confirming the results of Herrick in this respect)
and in Amphiuma and other forms. In Salamandra maculata,
in front of this ramus communicans, the middle branch of the
opthalmicus profundus suddenly bends downwards and goes to

7

56 JOURNAL OF COMPARATIVE NEUROLOGY.

the alveolar region of the upper jaw, while the palatine is con-
tinued forward as described by these authors, passing just in-
side the internal nares, and forward and beneath the premax-
illary bone.

Figure 2, Projection of fifth and seventh nerves of Salamandra maculata,
viewed from above; letters as before excepting of”, of°, middle and outer divis-
ions of the ophthalmicus profundus; {, ramus communicans between palatine
and profundus nerves. x 30.

In the Journal of Morphology Vol. XI, No. 2, Mr. Alvin
Davison gives an account of some features in the anatomy of
the young and of the adult Amphiuma. It is unnecessary to
notice here the whole article but there is a point of nervous anat-
omy mentioned which may fittingly be commented upon ina
Journal devoted to neurological matters. Mr. Davison says
(p. 401): ‘‘The most important and interesting structure is
found below and external to the eye in my smallest specimen,
seventy eight millimeters in length. There appears in this re-

KinGsLey, Nervous Anatomy of Amphibians. 57

gion a canal, one tenth of a millimeter long, which is walled by
columnar epithelial cells extremely regular in outline. Exter-
nal to the epithelial wall there is seen a thick layer inferiorly of
degenerated tissue, which is bounded by a thin layer of fibrous
connective tissue. In three other specimens, eighty eight,
ninety and ninety two millimeters respectively, no trace of this
degenerate canal could be discovered, and in the smallest spec-
imen I was able to detect it on the right side only.”’

In all probability it is this structure to which he refers later
in his paper (p. 405). After briefly summarising Wiedersheim’s
observations on the tentacular apparatus of the Gymnophiona
he says: ‘‘As I have already shown, there exists in my young-
est specimen of Amphiuma the atrophied remnants of the ten-
tacular apparatus. The columnar epithelial lining of the canal
is very distinct in about one dozen transverse sections through
the orbits. In some of the sections I have discovered what I
believe to be the degenerated retractor muscle. This apparatus
in Amphiuma has precisely the same relative location as in the
Coecilians. For some unexplainable reason neither Hay nor
Kingsley found this organ in the young embryo. . . The
occurrence of this degenerated structure in the young Amphi-
uma and its complete disappearance in the adult gives unmis-
takable evidence of the relationship of the Coeciliidae and
Amphiumide.’’ A single figure illustrates the point made.

Were it true that Amphiuma possesses, either in the young
or the adult, rudiments of a tentacular apparatus, the fact would
prove of great value to those who would recognize in the Gym-
nophiona only degenerate Amphiume. It is not, however,
‘‘unexplainable”’ why neither Hay nor myself found such a
structure for no tentacular apparatus exists in Amphiuma. 1
have considerable material in the way of young Amphiumae—
possibly forty specimens—embracing both younger and older
material than that in the possession of Mr. Davison and includ-
ing some from the same lot as the four specimens at his com-
mand. In the first place the structures described and figured
by him are not in the proper position for the tentacular appara-
tus, as a little careful reading of the Sarasin’s monograph would

58 JOURNAL OF COMPARATIVE NEUROLOGY.

have shown him. Secondly had he carefully examined the eye
muscles of his Amphiuma he would have found that all are
present, while the Sarasins say that the retractor muscle of the
tentacle is probably produced from the retractor bulbi.

| f 0
SOO oP

“yn

mx*

Figure 3. Portion of section through the head of a larval Amphiuma ; let-
ters as before excepting f, frontal bone; /, parietal bone; 2, ramus nasalis in-
ternus of ophth. profundus ; osf, orbitosphenoid; ¢7, trabecula; fs, parasphenoid;
9, optic nerve; m, maxillary bone; 4, blood vessel ; 6* and mx*, blood vessel and
branch of maxillary nerve constituting the tentacular apparatus of Davison.

On the other hand I find a canaland a solid structure lying
immediately beneath it, in the very place where Mr. Davison’s
tentacular apparatus appears, but I interpret the features differ-
ently. The supposed degenerate muscle is a peripheral branch
of the maxillary nerve, the tentacular canal is one of the branches
of the sub-orbital blood vessels. The only objection to this is
that our author describes the canal as lined by columnar
epithelium, a condition possibly the result of contraction of the
vessel and a consequent throwing of its intima into folds, or
possibly he has mistaken the contained blood corpuscles for
epithelial cells. The short course which he allows the canal is
explained by the fact that distally it breaks up while more
proximally it is compressed as it passes between two nerve

twigs.

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Pee COMPARATIVE ANATOMY VOR THE GINSULA

Tracy Eart Crark, B.S.
With Plates IX-XI1l,

TABLE OF CONTENTS.

Introductory Note, . F : : 4 ; ’ 5 59
List of Specimens Examined, : : : : O 60
Historical Sketch, : : : ; : : : a 62
The Development of the Operculums, . : ° 63
Early Development of the Insula, ‘ . 5 é 67
The Adult Human Insula, ; : 7 . : 69
Relation of the Insula to the Claustrum, ; ; 6 73
The Insula in the Primates other than Man, ‘ 75
The Insula in the Carnivora, : 5 ; ; : igh
The Insula in the Proboscidia, : : : : 82
The Insula in the Rodentia, : ‘ : c : 83
The Insula in the Ungulata, : 4 : ; ‘ 83
The Insula in the Cetacea, : : : : c go
Summary, ; : 0 : 5 : D 5 : QI
Synonymy, 3 5 : ; : : 5 . . 93
Bibliography, : ° : A : . ; : 94
Explanation and Description of Figures, é : : 97

The importance attached to this region of the human brain
and the wide divergence of opinion as to the existence of an
homologous area in other mammals led the writer, at the sug-
gestion of Professor Burt G. Wilder, to select it in 1890 as the
subject for his baccalaureate thesis. The extensive neurologic
literature and abundant material possessed by the Anatomical
Department of the Cornell University soon convinced the writer
of his inability to cover more than the macroscopic side of the
subject and that upon a very few specimens. Later the kind
offer of Professor Wilder to place at his disposal all of the ma-

terial at hand led to the prosecution of the work somewhat
further.

60 JOURNAL OF COMPARATIVE NEUROLOGY.

It is with a keen sense of gratitude that I now acknowl-
edge my indebtedness to Professor Wilder whose advice has
been frequently sought and who has always shown great interest
in the work. I desire also to thank Professor Simon H. Gage
and Instructor Pierre A. Fish for their interest and assistance,
and Mrs. S. P. Gage for the loan of specimens.

The following list, while incomplete, will give some idea
of the extent and nature of the material upon which the writer
has based his conclusions. The accession numbers are the serial
numbers in the Accession Book of the Department of Verte-
brate Zoology of the Cornell University.

Aon

No.) D3°* | Age Groups.

SUB-CLASS I. PROTOTHERIA.
ORDER I. MONOTREMATA.
76|Male Ornithorhynchus anatinus, duck-bill.

SUB-CLASS II. METATHERIA.
ORDER II. MARSUPIALIA.

Didelphys virginiana, common opossum.
Several specimens.

378 Macropus giganteus, giant kangaroo.
Two specimens.
oe me \ Hypsiprymnus moschatus, kangaroo-rat.

SUB-CLASS IM. EUTHERTA:
ORDER III. EDbDENTATA.
No specimens.
ORDER IV. SIRENIA.
844| Male Adult Manatus americanus, American manatee.
ORDER V. CETACEA.
670| Male Adult Globtocephalus melas, pilot-whale, black-fish. Fig. 35.

ORDER VI. UNGULATA.
Camelus bactrianus, Bactrian camel.

2177|Male

2122|Male Camelus dromedarius dromedary. Fig. 22.
776 Cartacus clama, fallow deer.
g61|Male Cartacus virginiana, Virginia deer, red deer. Fig. 23.

Ovis aries, domestic sheep. Figs. 32-34.
Many specimens.

3408 Female |Adult ]
3409|Female Adult r Bos taurus, domestic cow. Figs. 26-30.
3362| Female Juv. |

Juv.

2777 Lquus caballus, domestic horse.

2840) 6 mo. “ec “6 66 ce

2125 Maie Term ‘“ “ “ “

2095| Male Adult es Ge be es Fig. 25.

2259|Male jJuv. Equus asinus, burro, Fig. 24.

CLARK,

Comparative Anatomy of the Insula. 61

?
ae Sex Age. Groups.
ORDER VI. UnGuLatTa—Continued.
Sus scrofa, domestic pig.
Many specimens.
2123 Tapirus malayanus, Malayan tapir. Fig. 31.
ORDER VII. ToxoponmTia.
Fossil.
OrDER VIII. HyracorpeEa.
No specimen.
ORDER IX. RODENTIA.
Arctomys monax, woodchuck, marmot.
3075 Castor fiber, beaver.
Lepus cuniculus, rabbit.
Several specimens.
Mus decumanus, brown rat.
Mus musculus, common mouse.
Scturus hudsonius, red squirrel.
ORDER X. PROBOSCIDIA.
2181|Female Elephas indicus, Indian elephant. Fig. 21.
166 ORDER XI. CARNIVORA.
3124 5-8 wk \ Canis familiar?s, domestic dog. Figs. 14-18.
Many specimens.
277|Male Lynx rufus, American wild-cat, lynx.
157|Female |22 da. Felts leo, African lion.
309|Female |18 yrs. felis concolor, puma, panther. Fig, Io.
Felis pardalis, ocelot.
felis domestica, domestic cat. Fig. 19.
Many specimens.
Flyaena striata, hyaena.
2031|Male Procyon lotor, raccoon. Figs. 1, and 12.
Several other specimens.
Mephitis mephitica, skunk. Fig. 20.
Several specimens.
Putortus vison, mink.
197 Putorius domestica, ferret.
Phoca vitulina, seal. Fig. 9.
a645,Male Juv. Ursus thibetianus, Thibet-bear. Fig. 13.
ORDER XII. INSECTIVORA.
3356 Condylura cristata, star-nose mole.

265|Female |Juv.

ages.

Sorex platyrhinus, common shrew, shrew mouse.

ORDER XIII. CHEIROPTERA.

Vespertilio subulatus, common brown bat.
Several specimens.

ORDER XIV. PRIMATES.
Anthropopithecus troglodytes, Chimpanzee.
Cercocebus fuliginosus,
Macacus. Fig. 8.
Several specimens.

Fig. 7.

Numerous preparations of the human brain at various
See Figs. 1-6.

62 JOURNAL OF COMPARATIVE NEUROLOGY.

HISTORICAL SKETCH.

Vicq d’ Azyr (16, 1786) seems to have been the first to
call attention to this area in the human brain. He refers
(Pt. II, p. 26) to it as ‘‘ the convolutions situated between the
Sylvian fissure and the corpus striatum” and again (Pt. II,
p. 74) as ‘‘the convolutions which accompany the Sylvian fis-
sure.”’ These references would seem to indicate that at that
time all that was known was the fact of the existence of certain
gyres in that region which, on account of their concealed posi-
tion, had attracted but little attention; furthermore these are
the only references made to this region in his volume of sev-
eral hundred pages.

Monro (42, 1788) pictured three gyres of the human in-
sula seen after the removal of the ventral portion of the cere-
brum, but he neither named nor described them.

Hence it remained for Joh. Christ. Reil (1804-1806) to
give the first description as follows: ‘‘ Die Insel hat eine
langlichrunde Gestallt.”” Since that time the area has been
known as the ‘‘insula”’ or ‘‘island of Reil,” although many
other names have from time to time been applied to it (see Syn-
onymy, p. 93.) ,

The insula seems to have attracted little attention during
the next half century and it was not until about 1860 that the
study of cerebral localization caused increased importance to be
attached to it. Until several years later it was supposed that
the insula governed, at least in part, the power of articulate
speech. Authors had noted that in aphasics there was gen-
erally a lesion of the@nsula and the left subfrontal gyre. They
seem not, however, to have taken account of lesions confined
strictly to either area and they assumed that the insula had been
first affected and that later the lesion had extended into the ad-
joining area. Broca ( 4 ) disproved this. By comparing the
lesions found in postmortems upon a large number of aphasic
patients he reached the conclusion as early as 1861 that the
faculty of speech was located in the left subfrontal gyre, still
often called ‘‘Broca’s convolution.”’ During the next seven

CLARK, Comparative Anatomy of the Insula. 63

years a large number of aphasics were examined for the pur-
pose of verification, and in 1868 he published a résumé of the
facts upon which he based his conclusion. This discovery nat-
urally aroused great interest in the insula inasmuch as ‘‘ lesions
of the left subfrontal gyre generally extend into the insula,”
while those (2) ‘‘ confined strictly to the insula are very rare.”
In 1868 Broca (4, 113) pointed out that in aphasics there is almost
always a lesion in the caudal half of the subfrontal gyre of
either the right or the left side, and that this lesion is sometimes
confined exclusively to this area. However, in about one case in
twenty this area is apparently perfectly sound, but a lesion ex-
ists in the insula or an adjacent gyre with which the subfrontal
is continuous. The lesion is located in about Ig out of 20
times on the left side and the right side remains perfectly sound.
He had never found a case in which the patient was possessed
of this faculty and at the autopsy showed a lesion of both sub-
frontal gyres. Speech has, however, persisted in some patients
where an autopsy showed the total destruction of the right sub-
frontal. He also said he had noticed several cases of idiots who
had never been able to learn to read, where the subfrontal gyre
was absent on both sides.

So far as the writer has been able to learn, no satisfactory
reason has ever been given for this strange association of the
subfrontal region and the insula; yet if, as Meynert (gs) says,
‘‘fibers fromthe subfrontal gyre pass just entad of the insular
cortex,’ then it would seem very likely that a diseased condi-
tion of those fibers sufficient to cause loss of speech would
affect the overlying cortex of the insula producing lesions and
perhaps a breaking down of the cellular cortex, as frequently
happens. <A clot of blood, through pressure upon the insula,
has also been said to cause loss of speech.

THE DEVELOPMENT OF THE OPERCULUMS.

In 1892, Cunningham (45, 78) said of the human brain:
‘‘As Mihalkovics has pointed out, it is toward the end of the
second month of development that the first signs of the Sylvian
depression may be detected. At the same time, it is right to

64 JOURNAL OF COMPARATIVE NEUROLOGY.

state that its appearance is frequently delayed beyond this
stage and I have observed hemispheres well on in the third
‘month with hardly a trace of it.’”” What is later to become the
Sylvian fissure is now only a broad shallow furrow deepest near
the base of the brain and radiating in a fan-shape dorsad where
it disappears upon the lateral surface. Gradually by the
growth of what will later form the frontal, temporal and pari-
etal lobes, an overlapping or folding occurs and the fossa grad-
ually narrows until completely closed. What really happens
is that by the more rapid enlargement of these lobes in an en-
closed space, the intervening broad area- in the bottom of the
fossa, which early becomes fixed in position, is finally covered
and the lips of the Sylvian fissure are brought together. These
overlapping portions are the so-called operculums and in the
human brain are four in number, namely: the operculum arising
from the frontal and parietal, the preoperculum and the suod-
operculum from the frontal, and the fostoperculum from the
temporal lobe. These overlapping portions do not differ struc-
turally from the surrounding parts, being convoluted and cov-
ered with cinerea on both the ectal and the ental surfaces, and
the gyres of the ental surface are interdigitated with those of the
insula. The dorso-caudal end of the Sylvian fissure is the part
first formed and the first as well to become completely closed.
This is due to the rapid growth of the operculum and postoper-
culum.

In 1890 Beer (4, 309 (ix) ) said: ‘‘ According to Ecker,
Mihalkovics, etc., the Sylvian fissure of the adult is formed by
the gradual narrowing of a flat broad depression on the lateral
surface of the hemisphere, which is due to arrest of develop-
ment of the zzsula Rel in the 3rd month of fetal life.” The
conclusion that the insular area becomes depressed by a cessa-
tion of growth, while favored by many neurologists, appears to
me unwarranted. Presumably what happens as stated by
Wilder is that there is probably no complete arrest of develop-
ment, but that the surrounding parts develop much more rap-
idly so that in a short time they project farther laterad, leaving
the insula relatively depressed. While this seems to account

CiaRK, Comparative Anatomy of the Insula. 65

for all observed phenomena, the writer is inclined to the belief
that one very important factor has been underestimated. Dur-
ing the period when the insula first appears, the brain as a
whole is enlarging very rapidly. This enlargement in the re-
gion which will later become the Sylvian fissure it is assumed
may be due more largely to the expansion of the paraccele
than to the thickening of the paraccelian wall by the addition
of true nervous substance, which of course is always interstitial.
The anatomy of this region would seem to favor this latter
conclusion. The intimate connection of the insula with the
brain stem is such as to preclude any marked lateral extension
and, as the wall of the paraccele is then but little more than
membrane, any sudden increase of development, either by add-
ition to the true nervous parietes or by the expansion of the
paraccele, would cause the area caudad and dorsad to project
laterad giving outline to the insula by the formation of the cir-
cuminsular fissure and later the dorsal end of the Sylvian. It
also suggests the possibility of finding in a fetus of the
fourth to the seventh month an expansion of the paraccele
corresponding in a general way to the outline of the rudimen-
tary operculum. The conclusion given above agrees with ob-
servations upon the development of this region as described by
Cunningham, Ecker and others. It is also further believed that
this effect of expansion does not stop here, but that the over-
lapping of the insula and consequent formation of operculums
may be due in part to the expansion of the paraccele, and that
the subsequent thickening of the walls by the addition of true
nervous substance combined with the effects of growth in an
enclosed space may account in part for the continued conceal-
ment of the insular area in the adults of Primates and some
of the Carnivora.

The exact time of the closing of the Sylvian fissure by the
operculums is not known. In 1873, Ecker said it was from
the ninth to the tenth month.

In 1888 Mingazzini (41) said: ‘‘In one brain of the
eighth month, I have found the fissure almost completely
closed.”” The condition here presented I think is one of indi-

66 JoURNAL OF COMPARATIVE NEUROLOGY.

vidual difference rather than the rule, as I have examined sev-
eral brains of this age and have not seen one closed or
~ nearly so.

Broca in 1888 (4, 545) said: ‘‘Thissuperficial position of the
cephalic extremity of the insula has been observed, more or
less, in man, upon a great number of new-born children or
those of a few months old; after the second year it is rarely
seen except upon the brains of idiots and imbeciles (and also in
some deaf-mutes).”’

The determination of the exact time of closing of the Syl-
vian fissure in the normal human brain is of considerable mor-
phologic importance as it marks the completion of a period
of remarkable growth of these lobes; and in making a collec-
tion of brains between the eighth and twelfth months for this
purpose as many as possible should be obtained so that individ-
ual differences might not induce a wrong conclusion.

The operculums do not always completely close the Sylvian
fissure and hence the insula is exposed sometimes even in the
adult human brain. In 1887 Rolleston (49, 35), in his descrip-
tion of an adult male Australian brain, said: ‘‘ The island of
Reil is exposed on the left side. . . The exposure of the
island of Reil implies that the surrounding gyri are ill-devel-
oped; Broca’s convolution is thus shown to be defective, a point
of interest in an Australian savage whose language is primitive
It is questionable if
facts would bear out this conclusion, and while some of the gyres

)

as shown by its unclassified character.’

might in this specimen have been ‘‘ill-developed”’ it would
have been interesting to learn if this had been observed on
any other specimen.

The brain of the philosopher Chauncey Wright has a part
of the insula exposed. In 1889 Wilder (63,158) said: ‘‘ Whether
any of this condition is due to pressure during hardening
which may have occasioned also the peculiar roundness of the
temporal lobe, it is impossible to determine and Dr. Dwight
does not recall the condition of the parts when the brain
was removed.” In others, as that of the Swedish carpenter
(No. 318), the operculums not only conceal the insula but abso-

CiaRK, Comparative Anatomy of the Insula. 67

lutely overlap each other. These, withthe possible exception
of the Australian, are all types of individual difference and their
significance may be summed up thus: (1) if the insula is not
wholly concealed, it shows that if the insula is normal, the sur-
rounding parts have not reached their full development, while
if the insula is abnormally large, the surrounding parts may or
may not be fully developed; (2) if the insula is completely
covered so that the operculums overlap each other, it would
appear that, if the insula is normal, the surrounding gyri must
be abnormally developed, while if the insula were unusually
small, the normal operculums might even overlap each other.

EARLY DEVELOPMENT OF THE HUMAN INSULA.

We have seen that the rudiments of the Sylvian fissure
become apparent toward the end of the second month of
fetal life. There is then in the bottom of the shallow fossa
an indefinitely-defined oval or somewhat triangular area which
apparently develops more slowly than the surrounding lobes
and which finally becomes a subarea. As development pro-
ceeds, this area beeomes more elevated and hence more sharply
defined by the formation of the circuminsular fissure. The re-
gion thus mapped out is sometimes called the zzsular area be-
cause it is the part which will eventually become the insula in
man and presents a condition found in the adults of some
animals.

Mingazzini (49, 217, 1888) says: ‘‘ Until the end of the
sixth month the insula is quite smooth; constantly there ap-
pear in the seventh month those fissures [ circuminsular,
Wilder; vzgoles, Broca] which circumscribe the future gyres
of the insula. I can therefore not agree with Mikalkovics who
asserts that the insula is smooth up to the beginning of the ninth
month. I found this quite so once ina brain of the eighth
month upon which only one small cortical fissure appeared.
In the eighth month, they increase, oftentimes, to the number
of four, among which is produced the caudal one which is larger
and deeper than the others ; after the ninth month, there are,

d

as a rule, four fissures.’’ Mingazzini probably erred in the

68 JOURNAL OF COMPARATIVE NEUROLOGY.

above statement. The caudal one of the four fissures on the
normal insula. is never, so far as the writer has been able to
learn, ‘‘larger and deeper ’”’ than the transinsular fissure which
is cephalad of it and the observations of Cunningham (44, 347-
348) in 1891 seem to show pretty conclusively that even when
three fissures are present on this area, the caudal one is usu-
ally in the postinsula.

In the spring of 1890 the writer became convinced, as the
result of the study of the comparative anatomy of this region,
that future investigation would show that, barring the circum-
insular fissure, the transinsular, which is doubtless the most
constant and best, defined of the fissures on this area, would be
found to be the first to appear after the circuminsular and that
its homologue exists in some other animals at least. The
following table compiled from Cunningham, 1891 (14, 347-348)
seems to prove that this really is the order of development in
the human fetus. The brains enumerated below range from
five to six and a half months.

Transin-

CEREBRUMS T

State of Development of Insula. Total | sular f.

Right | Left present.
Iinsulasperfectly/smooth\ yee ee aaa 2 4 6 fo)
oe wit hutransins ula tiss Ure see re 3 4 7 7
a OC ‘Cfandsthe soneicep uplades=s==aas 6 2 8 8
ae CG ‘* f. one cephalad and one f. caudad; 2 I 2) 3
Totals): 2.2265 28eceo eee tha Sees 13 II 24 18

This same author (14, 347) says: ‘‘ Furthermore, there is
good reason to believe that in the development of the sulci and
gyri the right insula is usually in advance of the left, and also
that the process is greatly retarded in the female brain.”” The
first part of the above statement of Cunningham, while appar-
ently borne out by the table, seems remarkable inasmuch as
the left insula in the normal adult as usually larger than the
right.

In 1892 Cunningham (15, 15 summary) said: ‘‘In the adult
brain the insula is proportionately longer in the male than the
female. At all periods of growth it would seem that the insula
is relatively longer on the left side than on the right side. In

Crark, Comparative Anatomy of the Insula. 69

the negro brain, it would appear that the insula is relatively
shorter than in the European brain.”

The completion of the circuminsular fissure on the ventral
side is usually not accomplished until about the time of birth.
Prior to this completion of the circuminsular, which is prob-
ably influenced to a considerable extent by the cephalic growth
of the tip of the temporal lobe, the insula is continuous with
the ventral surface of the cerebrum through the Sylvian fossa.
It was probably this condition to which in 1885 Meynert (39, 4)
called attention as follows: ‘‘the island of Reil is connected
with a protuberance (the olfactory lobe) situated on the lower
aspect of the frontal portion of the fore brain.” It will be
seen (Figs. 1 and 2) that the lateral root of the olfactory tract
extends into the Sylvian fossa (that. portion of the Sylvian fis-
sure which does not close up). It is not believed, however,
that the fibres of this tract extend over any portion of the in-
sula, but on the contrary that they preserve approximately the
same relation to the insula as in the sheep (Fig. 34), the skunk
(Fig. 20), the cat (Fig. 19) and the mink, in each of which it is
to be noted that the fibres do not pass dorsad of the bottom of
the rhinal fissure, thus sharply demarcating the insula from the
olfactory lobe.

THE ADULT HUMAN INSULA.

Usually the adult human insula is entirely concealed within
the Sylvian fissure and can be seen only by divaricating the
lips of the fissure or after cutting them entirely away. Broca
(4, 651) says that it is not normally exposed after the second
year. This occlusion is a condition found so far as known in
all primates and in many of the imprimates. In all brains pos-
‘sessing an insula, the cortex bends in from the lateral surface
and passes without interruption under the fissures and over the
surface of the insula completely covering it whether convoluted
or not. In all brains observed by the writer, the gyres of the
operculums are interdigitated with those of the insula.

In 1889 Wilder (63, Prop. CXLI) wrote of this area in
man, ‘‘the insula is a part of the cortex, which, at one period

70 JOURNAL OF COMPARATIVE NEUROLOGY.

wholly superficial, is gradually covered more or less completely
by converging folds of the adjacent regions. The insula thus
becomes a subgyre, while the operculum, preoperculum, sub-
operculum and postoperculum are supergyres.”’

The adult human insula is always sharply demarcated by
the surrounding circuminsular fissure (7zgoles, Broca). Its posi-
tion is generally in a plane nearly parallel with the lateral sur-
face as shown in Figs. 3 and 4. An exception is shown in Fig 5.
In this specimen the gyres form a plane nearly perpendicular
to the lateral surface. This is a condition found in the sheep,
the pig (12,9), the calf, and some horses, and is believed to be
due to some peculiarity in the development of the brain stem.

In the adult, the insula is a large broad eminence, the sur-
face of which is richly convoluted. It generally possesses from
four to six gyres diverging cephalad, dorsad and caudad and
producing an appearance not unlike that of a fan. The num-
ber of gyres is subject to considerable variation even in the two
insulas of the same brain. The brain of Guiteau, the assassin
of Garfield, showed marked peculiarities in this respect. Ac-
cording to Spitzka (55, 386) the left insula contained seven fis-
sures and eight gyres, while the right had only five fissures and
six gyres. It will be noticed that the right insula had its full
complement of fissures and gyres while the left exceeded it by
two. Another case markedly different from this one has also
been reported by the same author. It, like the preceding, is
that of a murderer. He says, the left insula had ‘‘ fewer and
flatter gyri than that [six gyri] of the right side, and was
not far different from that of an orang in my possession.”” In
all normal brains, the left insula is said to be larger.

The insula is usually quite deeply fissured and is always
divided into two plainly unequal parts. This division is pro-
duced by a deep fissure extending dorso-caudad from the ven-
tral side—where it is deepest—to the dorsal margin where it
connects again with the circuminsular. This forms a cephalic
part, pretnsula, and a smaller caudal one, postensula. The pre-
insula is not only larger but contains more gyres. All of the
fissures of the insula communicate with the circuminsular dor-

CLARK, Comparative Anatomy of the Insula. |

sad but with the exception of the transinsular none of them
reach the ventral margin. The area common to all the gyres
of the preinsula, and from which they all appear to spring, is
usually the part most elevated and is called the pole of the insula.
Eberstaller (17, 741) says that the ‘‘limen insula ”’ (pole) is
found only or in a certain form in the human brain.

But for the unusually elevated pole in this specimen, Fig.
5 might be said to represent a nearly typical insula. The pre-
insula usually possesses three gyres of which the first (the one
most cephalic) and the third are usually the best developed and
these are frequently subdivided dorsad by short fissures. The
postinsula seldom possesses more than two gyres the first of
which is usually the larger. These gyres are united ventrad
and are always longer than those of the preinsula. Eberstaller
(17, 741) says the first gyre of the preinsula is the largest and
strongest and that the second gyre is usually weakly developed.
The postinsulas shown in Figs. 3 and 4 exhibit a peculiarity
which is very striking when compared with the usually simple
character of the area. The three small elevations of Fig. 3
and the one in Fig. 4 dorsad belong to the postinsula. It is pos-
sible that the shallow furrows separating these eminences may
have been caused by arterial pressure. Fg. 3 also shows
the relation of the insula to the medicornu. The specimen shown
in Fig. 5 is remarkable for the unusual elevation of the pole.
As previously stated this condition is probably the result of some
peculiarity in the development of the brain stem.

In 1887 Waldschmidt (61, 375) said the insula was larger in
educated persons. There are many facts favorable to this view
but it lacks confirmation.

Eberstaller and Cunningham have each called attention to
the apparently intimate relation of the transinsular and central
fissures. These fissures are very constant in the human brain,
they lie in the same plane, they take the same general direction
and they appear in the fetus at about the same time (5-6 mo.).
Eberstaller (17, 749, 1887) says: ‘‘ The cephalic insula is con-
nected wholly with the frontal lobe, the caudal insula with that
portion just caudad of the central fissure.”

72 JOURNAL OF COMPARATIVE NEUROLOGY.

In 1891 Cunningham (14, 338-9) said, that Guldberg had
suggested for the transinsular fissure ‘‘the very appropriate
-name of sulcus centralis insule which indicates net only its
central position in the island of Reil, but also its relation to the
central fissure on the outer surface of the hemisphere mantle.”
This author then endeavors to establish a connection between
gyres and fissures on either side of the transinsular with those
on the same side of the central fissure. He further states that
‘it is true that we cannot regard these corresponding convolu- ~
tions and sulci as being directly continuous with each other but
still in many cases something which approaches very nearly to
continuity occurs. Thus it is well known that the inferior pre-
central sulcus, the fissures of Rolando and the intraparietal sul-
cus are not infrequently carried downwards, so as to cut into
the fronto-parietal operculum and open into the Sylvian fissure.”’
There are many facts which seem to show that Guldberg and
Cunningham erred in their conception of the relation of these
two areas : :

1. The variations in the ventral extension of the central
fissure are believed to be due to individual difference.

2. The connection of the central fissure with the Sylvian,
when it occurs, is almost always by a small, variable opercular
fissure (Cunningham 14, 341-2). Wilder, in 1894, in the report on ©
the brain of an educated suicide, having apparently duplicate
central fissures, says (65, 2): ‘‘On the left both centrals enter
the Sylvian, with a depth of at least 5 mm. On the right, the
first central approaches the precentral, the second joins the Syl-
vian at a depth of about 3 mm.” So far as the writer has been
able to learn, this connecting fissure never completely divides
the operculum nor interrupts the circuminsular fissure in an
otherwise normal brain.

3. The absence of the central fissure has not been shown
to produce an appreciable effect upon the transinsular and if
either is absent it is more often the central fissure.

4. The insula is always sharply defined and is believed to
be a distinct lobe as sharply demarcated from the surrounding
areas as any lobe of the cerebrum, and the fissures and

Ciark, Comparative Anatomy of the Insula. 73

gyres upon its surface are also distinct and not dependent upon
those of the rest of the cerebrum.

5. The central fissure is not known to exist outside of the
primate brain, while, as will be shown, the transinsular fissure
is present in many imprimates and the relation of the transinsu-
lar to the Sylvian in them is sometimes as in man (see raccoon);
but more often it coincides in position and direction with the
Sylvian fissure.

6. The transinsular fissure gradually becomes less deep as
it approaches the circuminsular fissure dorsad, and it has never
been shown to extend beyond this fissure, while in some im-
primates it never reaches the dorsal margin of the circuminsular
fissure.

7. The central fissure is sometimes double; the writer
has been unable to find a single recorded instance of the dupli-
cation of the transinsular fissure.

8. The reasons given by Cunningham (13, 287) to show
that because the preoperculum is (as he thinks) absent in the an-
thropoid it necessarily follows that a portion of the insula is
also absent, are not well founded. The human insula has near-
ly or quite the same form before as after the appearance of the
preoperculum and the writer fails to see why it should be oth-
erwise in the ape.

g. The mononym ‘‘transinsular” fissure (Wilder) indi-
cates better the relation of this fissure to the insula and is far
preferable to the polyonym ‘‘sulcus centralis Reilii’? of Guld-
berg and Cunningham.

The blood-supply of the insula is derived from the branch-
es of the medicerebral artery which ramify over its surface.
The main branch lies in the transinsular fissure as shown in
Fig. 4. From these branches small arteries penetrate the cor-
tex directly.

THE RELATION OF THE INSULA TO THE CLAUSTRUM.

On account of its intimate connection with the brain-stem,
the insula has been called the stem-lobe or Stammlappen. En-
tad of the insular cortex (see Fig. 6) but separated from it by

74 JOURNAL OF COMPARATIVE NEUROLOGY.

a band of myelinic fibers, lies another cellular area called the
claustrum (Burdach). These fibers, says Meynert, have their
- origin partly from the subfrontal gyre and partly from the un-
cus from which they radiate in a fan-shape separating the areas
referred to above. The same author also says (37, 674): ‘‘The
fibers of the fasciculus uncinatus traverse freely the substance of
the claustrum as well as that of the zucleus amygdale. The an-
terior cord-like and hook-shaped part of the fasceculus uncinatus is
joined by bundles of fibers distributed, as it were, in layers
which pass through and along the surface of the claustrum, con-
stituting an important part of the medullary substance of the
island (of Reil) and of the external capsule.”’

In 1889 Spitzka (56,172) said the claustrum ‘‘corres-
ponds in extent nearly with the extent of the insula.”

Obersteiner in 1890 (42, 68) said of the claustrum, ‘‘its
lateral surface adapts itself to a certain extent to the cortex of
the island of Reil, exhibiting similar small elevations and de-
pressions.”’

Until recently, the claustrum has been assumed to be pecu-
liar to the primate brain, and was an object of much specula-
tion; but the researches cf Betz, Meynert, Duret, Browning and
others seem now to prove beyond a doubt that it is really a part
of the insula which became separated from the cortex proper
by the growth of the fibers referred to above. In1879 Richet
(48, 23) wrote: ‘‘It appears that in the brains of idiots, the
white lamina, which separates the insular convolutions from the
avant-mur is absent, and the avant-mur really becomes the in-
ternal layer of the cortex cerebri (Betz).” The same author
(48, 24) quoting from Duret, says the circulation is the same as
that of the insula. Browning in 1889 (5, 234) agreed with Duret
and stated that the blood supply of the claustrum passed
through the cortex of the insula and not through the precrib-
rum (anterior perforated space). This being established it would
seem that the presence of a claustrum was indicative of the
presence of an insula. It also suggests the possibility of these
fibers passing so far entad as not to demarcate a claustrum as is
probably the case in the sheep. The former inference regard-

CLaRK, Comparative Anatomy of the Insula. 75

ing the presence of a claustrum indicating the presence of an
insula at first seemed plausible but later reflection has caused
the idea to be abandoned (see discussion under Carnivora).

THE INSULA IN THE PRIMATES OTHERK THAN MAN.

The anthropoid apes, which in structure are so closely
allied to man, possess a well developed insula.

Leuret and Gratiolet seem to have been the first to recog-
mize this area. They say (91, Il, 112):)* Le lobe central_parait
particulier a homme et aux singes, peut-etre voit-on quelque
chose d’analogue dans les makis, mais on ne voit rien de sem-
blable chez les autres mammiféres.”’

In 1891 Cunningham (13, 287) said: ‘‘One of the most re-
markable characters in the cerebrum of the orang and the chim-
panzee is the fotal absence of the frontal and orbital opercula.
The temporal and fronto-parietal opercula are alone present.”
There is some diversity of opinion as to the entire ‘‘ absence ”’
of the suboperculum in these brains and Cunningham also admits
the presence of a fissure which forms the cephalic boundary of
the operculum but he does not believe it homologous with the
presylvian fissure and hence does not recognize a suboperculum.
Cunningham (13, 287) also says: ‘‘It is curious that while the
anthropoid should be so absolutely destitute of a frontal and
an orbital operculum, there are many of the lower apes (e. g.
baboons, macaques, etc.) which show a faint trace of the orbital
operculum.”

In 1880), Parker, (46) ustated that the insula of) the
chimpanzee ‘‘ is well developed and is marked by several con-
spicuous radiating convolutions (gyri breves, Gall) and lies en-
tirely concealed beneath a well-developed operculum.”

In 1877 Major (34, 46) said the insula was relatively as
well as absolutely smaller in the chimpanzee, etc., than in
man.

Hartmann (26, 195) in 1886 wrote that ‘In the gorilla,
chimpanzee, and orang, the island of Reil is generally—at least,
according to my experience—overlapped by the operculum,
although there are instances in which this is not the case.”

76 JOURNAL OF COMPARATIVE NEUROLOGY.

In 1878 Broca (4, 645) said the insula of the gorilla bears
‘‘three gyres as in the orang, while there are four in the chim-
panzee.’’ Chapman in 1879 (g, 61) said: ‘‘The central lobe, or
island of Reil, which is very slightly convoluted, is entire con-
cealed in the chimpanzee.”’

Spitzka (56, 255) says that the gyres of the orang’s insula
correspond as to their direction and relations to those of man,
though less marked. He further states that ‘‘in every anthro-
poid dissected by myself, I find these gyri and sulci; and one
sulcus is a constant feature of even the Cynocephali.”’

The specimen here shown (Fig. 7) does not exhibit an
area so well marked as those described by the above authors
and this is probably due to the undeveloped state of the chimpan-
zee brain at this age. Excepting the circuminsular, the fissures
of the insula are very rudimentary and few in number. This
insula was entirely concealed within the Sylvian fissure. There
seems to have been a feeble attempt at producing a transinsular
fissure but no apparent approximation to a pole. Broca (4, 369)
says: ‘‘ L’insula est toujours simple chez les cébiens et les pith-
éciens, ainsi que chez gibbons. Chez les grands anthropoides
et chez l’‘homme, elle se subdivise en un certain nombre de plis
qui convergent vers le pole et vont gagner successivement les
divers points de la rigole supérieure, qu’ils traversent pour se
jeter profondément dans le lobe frontal.”’

Marchand (36, 1893) says: ‘‘In the lower apes the isle
of Reil isexposed. This is the case in microcephalic idiots.”

Spitzka (56, 173) has shown that the claustrum in present
in the baboon and that it is similarly located to that of man.

The insula of the macaque monkey (Fig. 8) shows a well
rounded eminence deeply imbedded in the Sylvian fissure. It
is sharply demarcated by the circuminsular fissure but is other-
wise unfissured and is’ about twice as long as broad.

Cercocebus fuliginosus presents an insula very similar to that
of the macaque. It, like the last-named, shows a well-rounded
eminence and a well-defined circuminsular fissure. The insula
was deeply imbedded in the Sylvian fissure.

There are several lemurine brains in the Cornell Museum,

CiarK, Comparative Anatomy of the Insula. 70

but they were not available for examination at the time this
thesis was prepared.

In 1866, Flower (g1) said of the Javan loris (Stexops
javanicus) on separating the lips of the Sylvian fissure ‘‘ no
distinct median lobe, or insula, could be traced.” The same
author also says ‘‘In the sulci of the outer face in the lemur,
the Sylvian fissure is deeper especially at its anterior or lower
part and conceals a small but distinctly marked insula or me-
dian lobe.”’

ORDERS CHEIROPTERA AND INSECTIVORA,

The specimens belonging to the above named orders, so far
examined by the writer, showed no evidence of a macroscopic
insula.

THE INSULA IN THE CARNIVORA.

The area which represents the insula in this order is, in
general, not well developed, but in a more or less rudimentary
form may be said to be fairly constant. As a macroscopic area,
however, I have been unable to recognize it in the domestic cat,
the Angora cat, Lyx rufus, the ocelot (Felis pardalis), the
skunk (Mephitis mephitica), the mink (Putorius vison) and the
ferret (Putorius domestica). My observations made in the
latter part of 1893 upon the seal (Phoca vitulina) agree with
the conclusion of .P. A. Fish (29 %, 16, 1896) who has
shown that the Sylvian fissure has not suffered any
marked displacement and that Spitzka (1890, Azmertcan Nat-
uralist, XXVI, 115-122) erred in assuming a vertical com-
municating fissure (v. 7. Fig. 9) as the true Sylvian. The posi-
tion of the insula shows conclusively that the caudal one of
these two fissures is the true Sylvian. Dr. Fish also says: ‘‘The
vertical and the true Sylvian fissures meet superficially at the
latero-ventral angle of the cerebrum and if the sides of the Syl-
vian be separated, it will be seen that the vertical fissure in-
stead of directly joining the Sylvian becomes a submerged fis-
sure . . . andcrops out again on the ventral surface on
the front or cephalic wall of the mouth of the Sylvian.

This condition is found on both sides.’’ The insula is repre-

78 JOURNAL OF COMPARATIVE NEUROLOGY.

sented in the seal (Phoca vitulina ) and the panther (Fels con-
color) in Figs. g and Io respectively. In each the area is devoid
of fissures except the circuminsular, thus indicating its very rud-
imentary character. The area is only slightly elevated and was
entire concealed within the Sylvian fissure. It is present and
of about the same rudimentary character in the hyena where it
is flatter than in the preceding and is entirely concealed. It is
concealed and rudimentary in the lion. In 1879 Pansch (45, 166)
said that it is present but concealed in the fox.

| Fig. 11 represents this area in the raccoon. The circum-
insular fissure is interrupted at two points leaving the insula
joined to the temporal lobe caudad and the cephalic boundary
ill defined. This elongated and flattened area is crossed by a
fissure which is believed to represent the transinsular, although
it does not correspond exactly with the direction of the Sylvian
(see Fig. 12), as is usually the case in the imprimates at least.
Nevertheless it almost completely divides the area into a pre-
insula and a postinsula, is deepest at its junction with the rhinal
and at that point it corresponds in position with the Sylvian.
This lack of conformity is strongly suggestive of a displacement
of the Sylvian fissure as the result of growth in an inclosed
space which may have carried the dorsal end of the Sylvian
caudad while the bounding parts of the ventral end, which is
more closely connected with the brain stem, have maintained
their original position. Future investigation may also show that
some peculiar development of the frontal or parietal lobes or of
both has aided in bringing about this condition. The relation
of the transinsular to the Sylvian fissure in this brain is strik-
ingly similar to that in the human, but in the raccoon there is
no evidence of the central fissure. The area is otherwise un-
fissured, but slightly elevated and, with the exception of the
cephalic third which lies concealed in the Sylvian fossa, it is
completely hidden within the lips of the Sylvian fissure. As
previously stated, the cephalic boundary is ill defined and the
insular area graduates out into the frontal lobe as in the case of
young pigs. The plane (plane of fissured surface) of the insula
in this specimen forms an angle of more than 45° to the lateral

CLaRK, Comparative Anatomy of the Insula. 79

surface while that of the seal, panther, hyena and most primates
is nearly parallel to the the lateral surface.

The insula of the Thibet bear (Ursus thibctianus), Fig.
13, is very different in its appearance from the preceding—as
if, instead of the prolonged growth caudad, as in the raccoon,
the surrounding areas which presumably have reached a higher
state of, development, had produced a cephalo-caudal compres-
sion of this area, resulting in the formation of two parallel gyres
separated by the transinsular fissure. Relative to the length of
the cerebrum, the insula in this specimen is much shorter than
that in the raccoon. The transinsular fissure here is deep and
coincides very closely both in direction and position with the
Sylvian. The area is sharply demarcated by the circuminsular
fissure except at the cephalic end where a slight depression
probably marks the cephalic boundary. The area is well
rounded and the plane of the insula is parallel to the lateral sur-
face. The insula was not wholly concealed, a small portion of
the caudo-ventral end of the cephalic subgyre being visible be-
fore dissection. The area was almost entirely within the Syl-
vian fissure. In 1888 Turner (59, 566) said: ‘‘ In the brain of
the Polar Bear, I have shown that an entire arched convolution
is concealed within that [Sylvian] fissure.”’

This area in the dog (Cans familiaris) is situated normally
at the bottom of the Sylvian fissure and is entirely concealed.
The plane is parallel to the lateral surface or nearly so. It isa
well rounded, oval area somewhat triangular in form, is sharply
defined by the circuminsular fissure and, as stated by Huxley,
is usually unfissured. Figs. 14 and 15 represent an exceptional
condition. The insula was exposed on both sides and was sit-
uated almost wholly in the Sylvian fossa. The area was well
rounded and its outline approximately rectangular. Another
peculiar specimen is shown in Fig. 16. Here the insula, while
entirely concealed within the Sylvian fissure, was crossed by a
fissure which may represent the transinsular fissure and if so
the preinsula is the smaller. In order to determine with greater
certainty the nature of this fissure the area was removed and
sectioned. The shallowness of the fissures (Fig. 17) plainly

80 JoURNAL OF COMPARATIVE NEUROLOGY.

shows that the fissure crossing this areais not a part of the
circuminsular but an independent fissure, probably the transin-
~ sular as previously stated. The small area cephalad undoubt-
edly represents a preinsula. Owing to the normally simple
character of this area in the dog, these individual differences
are very striking.

A transection of the cerebrum of a dog is shown in Fig.
18. The insula appears as it normally exists concealed by the
overlapping portions of the temporal and parietal lobes. The
myelinic fibers of the olfactory tract readily distinguish the
rhinal fissure and it will be noted that they do not extend be-
yond the bottom of this fissure. A band of myelinic fibers
extending apparently from the dorsal overlapping area of the pari-
etal lobe, passes through the insular cortex cutting off the ental
layers which constitute an area probably homologous with the
claustrum. The study of sections caudad of this one shows
that this band of fibers ventrad of the insula bends around into
the temporal lobe. It would thus appear that a part of them at
least might be association fibers. Fibers also given off from
this band are distributed through the claustrum. Myelinic
fibers are also found in the ectal dense layer of cortex of the
insula and they extend for the most part parallel with the sur-
face.

The insula receives its blood-supply directly from minute
branches of the medicerebral artery, which pass in from the sur-
face and which are seen in longisection in Fig. 18. The writer
has been unable in most cases to determine the origin of ves-
sels found in the claustrum as they were seen only in transec-
tion. A few however have been found which passed directly
across the area as in the case of the one represented in the dor-
sal end of the claustrum. These would seem to indicate that
a part of the supply might be received directly from the surface
arteries. In the vicinity of the fiber tracts, arteries, in general,
seem to follow the direction of the length of the fibers and not
to cross them.

As previously stated, no macroscopic area appears at the bot-
tom of the Sylvian fissure of either the cat (see Fig. 19) or the

CiarK, Comparative Anatomy of the Insula. 81

skunk (Fig. 20). In each the width of the Sylvian fissure is
practically the same throughout its length and at the bottom as
near the surface. The study of many transections of the Sylvian
region confirms the statement that there is no marked widening
of the Sylvian fissure at any point ; there is absolutely no sign
of a circuminsular fissure and consequently no evidence of an
ectal area homologous with the insula. Recourse was then had
to the Weigert method with the result that it has been demon-
strated in each that a cellular area had been separated from the
cortex entad of the Sylvian fissure by a thin lamina of myelinic
fibres. This area is similarly situated to the claustrum of the
dog and in the skunk at least the fibers appear to arise from
the area dorsad of the Sylvian and pass to some area ventrad or
vice versa. In the cat, however, this lamina appears to connect
the area ventrad of the Sylvian fissure with the central mass of
myelinic fibers rather than with the area dorsad of the Sylvian.
The origin of these fibers does not effect the question as to
whether or not this is really a claustrum for, while it is known
that fibers from the uncus and subfrontal gyri pass entad of the
insula and assist in the demarcation of a claustrum in the human
brain, it is not known but what fibers having a different origin
also take part. Certain it is that if these myelinic fibers (which
appear to be of the association type in the dog and skunk) were
not there this area would remain a part of the cortex as has
been shown is sometimes the case in the human brain. The
fibers which make up this lamina are much fewer than in the
dog and the number is still less in the skunk than in the cat.
Some twelve days after I had thus independently reached the
conclusion that this area was homologous with the claustrum, my
attention was called by Professor Wilder to an article by
Graeme M. Hammond, in 1881 (96). This article contains fig-
ures showing that the author had noticed the area in the cat,
sketched it though imperfectly and named it the claustrum. In
1889, Spitzka (56, 173) also figured this area in the cat but did
not name it. The writer was unable to recognize a claustrum
in (Weigert) transections of the brain ofthe mink. This animal
has no Sylvian fissure.

82 JOURNAL OF COMPARATIVE NEUROLOGY.

The significance of the presence of the claustrum is diffi-
cult to determine. As previously stated, the existence of a
~ claustrum might, in general, be taken to indicate the presence
of an insula but such is not believed to be true in either of
these instances. Presumably if a rudimentary insula did exist in
the cat, then only a small portion of the claustrum would corres-
pond therewith; and if only a part of the claustrum belongs to
this area, then, as in this case where the claustrum is of consid-
erable size, the larger part of the claustrum has necessarily no
conection with the insula. Indeed it might exist quite as well
without an insula. Hence it would appear that the only signifi-
cance attached to the presence of a claustrum in such cases is
that the cortex at the bottom of the Sylvian fissure is relatively
farther entad than in those brains where the area is not so de-
marcated, as in the sheep and mink.

Turner in 1888 (59, 566) said: ‘‘In the true carnivora, the
Sylvian convolution was, asa rule, superficial and on the cra-
nial aspect, though in the otter and badger indications.of the
depression of its anterior limb within the fissure were seen. In
the seals and walrus, the concealment of this convolution was
still more marked, so that the brains of these animals form ap-
parently, in this particular, a transition to those of man and apes,
in which the concealment of the island is complete.’

9 Nie

THE INSULA IN THE PROBOSCIDIA.

In the single specimen of the Indian elephant examined
by the writer, the insula (Fig. 21) is only slightly developed.
It consists of an almost flat area in the bottom of the Sylvian
fissure and is made up of three gyres, two of which belong
to the postinsula. This disposition of the insular area suggests
that in the unusual dog (Fig. 16) except that in the latter the
postinsula is at the same time more elevated. In the elephant
the postinsula contains the greater number of gyres but the
preinsula is the more elevated. The entire area is deeply
imbedded in the Sylvian fissure and extends ventrad as far as
the rhinal fissure. This observation is contrary to that of Owen,
1868, who declares (44, 129) that ‘‘ the minor inter-Sylvian con-

Ciark, Comparative Anatomy of the Insula. 83

volutions are exposed in the sheep and elephant.” He also says
(44, 123) ‘‘It is well marked and rises high up the Sylvian fis-
sure in the Proboscidians.”’ In 1879 Spitzka (5g ) said that the in-
sula in the elephant is completely covered. The largest branch of
the medicerebral artery lies in what I have called the transinsular
fissure but this artery does not reach the dorsal margin of thisarea.
At about one-half or two-thirds of the distance from the ven-
tral boundary of the insula, the artery leaves the area to pass
dorsad into the Sylvian fissure. This peculiar condition seems
to have been brought about by the very unusual growth of the
area dorsad of the insula, which fold has been projected ventrad
as a rudimentary subopercular fold.

THE INSULA IN THE RODENTIA.

None of the members of this order so far as examined by
the writer showed any evidence of a macroscopic insula. Tran-
sections of the Sylvian region prepared by the Weigert method
failed to show the presence either of an insula or a claustrum in
the woodchuck. |

THE INSULA IN THE UNGULATA.

With the exception of the primates, members of this order
seem in general to have reached a higher state of insular devel-
opment than those of any other order, a significant fact when it
is considered that this order is usually placed so far down the list
on account of other characters. The specimen of the camel here
shown (Fig. 22) can hardly be taken to indicate much more
than the existence of an insula in this animal. The area is
nearly flat and presents no fissures other than the circuminsular.
The insula is proportionally very small and shows on the whole
a rudimentary state of development compared with the sur-
rounding lobes. It was completely concealed within the Sylvian
fissure, the ventral end scarcely reaching the rhinal fissure ; the
wider end of the insula is dorsal. It is concealed and rudimen-
tary in the bactrian camel (Camellus bactrianus).

The deer (No. 961) presents a well defined area and at the
same time one not indicating a high degree of development.
The insula (Fig. 23) was completely concealed and is situated

84 JOURNAL OF COMPARATIVE NEUROLOGY.

almost wholly in the Sylvian fossa, only the caudal end extend-
ing dorsad into the Sylvian fissure. With one exception the
- fissures are merely broad shallow depressions which indicate a
tendency to divide the area into five gyres. The caudal fissure
probably represents the transinsular and is the only one indenting
the lateral surface of this area. The plane of the insula is
nearly perpendicular to the lateral surface; the surface is well
rounded and throughout its entire length lies just dorsad of the
olfactory tract. The insula is present also in the fallow deer
(Cariacus clama) and exposed on both sides. At least three
fourths of the insula is cephalad of the ventral end of the Syl-
vian fissure. The transinsular fissure is rudimentary on the
left side but better developed on the right. The difference in
the position, relative development, form, and relations of the
insula in the camel and deer are very great and more marked
than one might expect in animals so closely related.

The area which represents the insula in the sheep (Figs. 32-
33) is, contrary to the rule, exposed. It is probably due to this
fact that this area has not previously been treated by writers
on the sheep brain. Only Leuret and Owen seem to have
recognized it. The former states that, ‘except in) the wsheep:
they [supplementary convolutions] are found ‘‘only in the brains
of man, elephant and monkeys.’”’ Owen says: ‘‘the minor in-
ter-Sylvian convolutions are exposed in the elephant and
sheep.”

This area, as has been rightly said, is exposed in the sheep
and throughout its length lies just dorsad of the olfactory tract
in the Sylvian fossa. The rhinal fissure which separates these
areas is always well defined. In adults the lateral exposed sur-
face is usually indented by two (apparently three) fissures—the
most cephalic and caudal being found upon dissection to be
parts of the circuminsular, while the median one is the lateral
outcrop of what the writer considers the homologue of the
transinsular fissure. Other indentations are frequently noticed
but they are usually slight and are probably caused by pressure
of branches of the medicerebral artery which lie in them. Up-
on dissection, it becomes evident from the greater fissuration

CrLarK, Comparative Anatomy of the Insula. 85

that the dorsal and not the lateral surface is homologous to the
lateral areas of most mammals and that the plane of the insula
is perpendicular to the lateral aspect. Presumably in this brain
as in the human the circuminsular fissure is the first developed
and in adults is usually complete. In younger specimens
however it is quite noticeable that this fissure is interrupted in
one or more places as on the lateral surface at the cephalic end
of Fig. 32 and at the dorso-caudal boundary of Fig. 33. With
the exception of the circuminsular but one fissure of this area
appears to be constant and is the only one extending upon the
lateral as well as the dorsal surface. This fissure is continuous
with the rhinal ; in it lies the largest branch of the medicere-
bral artery which passes dorso-mesad into the Sylvian fissure ;
it coincides throughout most of its course with the direction of
the Sylvian, divides more or less completely the area into a
preinsula anda postinsula and is the fissure which, in the dis-
cussion of the lateral surface, was called the transinsular fissure.
This branch of the medicerebral artery after traversing nearly
two thirds of the length of the transinsular from the lateral sur-
face mesad suddenly leaves it and passes up into the Sylvian
fissure, thus giving the appearance as if the nearly equilateral
triangular caudo-mesal portion of the caudal gyre of the pre-
insula had grown caudo-ventrad of the artery. Presumably
what has happened is that a displacement of the Sylvian fissure
has occurred due toa greater development of the temporal or
occipital lobes than the frontal and parietal; that this growth
in an inclosed space has resulted in carrying cephalad the dor-
sal end of the Sylvian and with it the artery, thus removing
the artery from the mesal end of the transinular, where presum-
ably it originally was lodged. The vertical position of the Syl-
vian fissure would seem to indicate that such a displacement
had occurred. The relation of the Sylvian to the transinsular
fissure is very striking when compared with that in the raccoon,
where the Sylvian was mostly caudad of the transinsular. In
two instances only have fissures other than those above men-
tioned been seen on the lateral surface of the sheep brain and in
each case, as might be expected, they were in the preinsula.

86 JOURNAL OF COMPARATIVE NEUROLOGY.

The dorso-lateral aspect (Fig. 33) shows the preinsula to con-
sist of three gyres while the postinsula has but one. The gyres
- of the insula are in general simple. One specimen, however,
showed the caudal gyre (postinsula) subdivided into three parts.
The fissures grow deeper as they approach the meson except
the transinsular but it is not known that any are constant. The
sheep brain exhibits two unusual conditions shown in the tran-
section of this brain (Fig. 34): first, that a bundle of myelinic
fibers enters the insula from which it might be inferred that this
area is functional, or at least assists in the performance of a
function. These fibers seem to pass principally to the dorso-
lateral part of this area, although it is evident that many are
given off along its course to other parts of the area mostly
dorsad. Secondly, there is no indication of a claustrum. It
is not believed that any great significance can be attached
to the apparent absence of this part in the sheep other than
that the insula in this animal is relatively farther laterad than
in those where the claustrum becomes so demarcated and hence
the fibers from surrounding areas which in some other animals
pass through the cortex here pass wholly mesad. The blood
supply is derived wholly from branches of the medicerebral
artery which extend over the surface. The position of the
rhinal fissure and the relations of the insula to the olfactory -
tract are clearly shown. The myelinic fibers of the latter ex-
tend only to the bottom of the rhinal and in no case have fibers
been found extending upon the insular area. This fiber area of
the olfactory tract extends considerably farther ventrad than
shown (Fig. 34) and at the ventral end the fibers are most
numerous and collected into a bundle of considerable size.

The insula of the cow (Figs. 26-29) is well developed, ex-
posed on the lateral aspect and lies almost wholly within the
Sylvian fossa. It presents in this animal peculiarities not pre-
viously met with. The area in but one of five specimens was
completely divided into a preinsula anda postinsula. In this
one (3362) the transinsular fissure was well marked, was deepest
at the latero-ventral end, and was continuous mesad with the
circuminsular. The fissure cephalad of the transinsular also

CiarK, Comparative Anatomy of the Insula. 87

completely crossed the insula but was shallow at the ventral
margin. The area is more often incompletely divided by the
transinsular fissure which, while it is of considerable length and
depth, is almost always confined to the lateral surface. The
part most elevated in the five specimens examined lies in the
postinsula always directly caudad or caudo-mesad of the dorsal
end of the transinsular fissure. What has been assumed as the
plane of the insula is at an angle somewhat greater than ninety
degrees with the lateral surface. The caudal and caudo-lateral
surfaces of this elevated portion slope very abruptly from the
apex of this elevated portion to the temporal lobe. The slope
toward the mesal boundary is always more gradual and becomes
still more so as the cephalic boundary is approached. A cu-
rious condition exists at the caudal end of the preinsula where,
on the lateral surface, the appearance is as if a quite successful
effort had been made to tuck that part caudo-mesad under
the postinsula. This is more marked on the left side (see Fig.
26) than on the right (Fig. 27), and the crowded appearance of
this area seemed more marked in adult than in younger speci-
mens. The surrounding lobes appear to be well developed,
while the olfactory tract is enormous. The study of this brain
seems to confirm the impression that these remarkable features
are due to growth in an enclosed space. The insula shows the
effects of compression in a marked degree.

The circuminsular fissure of the right side (Figs. 27-28) sharp-
ly defines the insular area except at the temporal lobe where the
fissure is interrupted and a junction of the insula with the tem-
poral lobe is formed at the lateral surface. This insula consists
of seven gyres only one of which belongs to the postinsula.
On the left side of the same specimen (Figs. 26 and 29) the
circuminsular fissure is also interrupted with the formation of a
similar junction as on the right side. Two interruptions of the
circuminsular are found at the cephalic margin on the left side.
The dorsal surface is divided into four gyres, three of which
belong to the preinsula. A zygal fissure’ (Fig. 29, 2/) exists near

1 See Wilder (64, 155).

88 JOURNAL OF COMPARATIVE NEUROLOGY.

the middle of this area, the base extending in the direction of
the length of the area. While this surface is much less fissured
than the corresponding surface of the right side, the lateral sur-
face of the left side appears much more complicated. In the
left insula of the cow (3137) the transinsular fissure was wholly
exposed on the lateral surface; there was no interruption of the
circuminsular at the cephalic margin, and the dorsal surface pre-
sented five gyres, four of which belong to the preinsula.

In 1890, Turner (61, ‘‘ Fig. 26’) gave a wrong idea of the
Sylvian fissure (see Fig. 30) in the cow. He mistook the
transinsular fissure for the Sylvian.

In the insula of the cow, individual and lateral variations
are perhaps more marked than in that of any other animal ex-
amined. We have here exemplified also the peculiar folded
appearance first noticed in the bear but more marked.

The area representing the insula in the burro (Aguas asznus)
is better developed than that in the deer. It is well rounded
and, except at two points along the cephalic boundary, the area
is sharply defined by the circuminsular fissure (Fig. 24). As in
the deer, the area is divided into a preinsula and a postinsula by
the transinsular fissure, the latter area containing but one, while
the former consists of four gyres all well developed and sharply
defined. There is no approximation to a pole asin man. The
location of the area is similar to that of the deer, only the caudal
one third lying in the Sylvian fissure. The two most cephalic
gyres of the preinsula were exposed before dissection and the
plane of the area makes an angle of not more than 60° with
that of the lateral surface.

In 1871, Lussana and Lemoigne (33) stated that the insula
of the horse was of considerable size. The writer has exam-
ined five brains, two of which, at least, are worthy of descrip-
tion. The first was that of a work-horse (2777, R. half) which
showed five gyres exposed previous to dissection. Upon dis-
section the plane appeared almost perpendicular to the lateral
surface, the gyres were six in number and the fifth (from the
cephalic end) was subdivided by a small fissure at the mesal
end, The fissure separating gyres 2 and 3 is deep, extends

CiarK, Comparative Anatomy of the Insula. 89

over the dorsal surface and almost completely divides the pre-
insula upon the lateral surface.

The insulas of the ‘‘Sage horse” (Fig. 25) consist of
five gyres each, of which three belong to the preinsula and two
to the postinsula. Before dissection the left insula showed four
gyres exposed while the right showed three. One of the main
branches of the medicerebral artery lies in what I have called
the transinsular fissure (Fig. 25). This fissure is well marked
on both sides. In the left insula the two most cephalic gyres
are nearly perpendicular, while the other three are at an angle
of about 60° to the lateral surface. On the right all the gyres
are in about the same plane which lies nearly perpendicular to
the lateral aspect. Those of the postinsular seem better devel-
oped and the first gyre of the postinsula is the one most ele-
vated. There seems to be an approximation to a pole in this
specimen not found in any other animals than the primates.
The second gyre is also the smallest as in man.

The insular region of the tapir (Zapzrus malayanus, Fig.
31) presents a very peculiar appearance, from the fact that be-
tween the area which I have called the insula and the rhinal fis-
sure there seems to have arisen a corrugated area which is not
believed to belong to the insula at all. This area extends from
the frontal to the extreme end of the occipital lobe and through-
out its course lies just dorsad of the rhinal fissure which is in-
terrupted at several points on the left side but is continuous on
the right. The fissure dorsad of this area is nearly parallel to
the rhinal except near the caudal end. The area included be-
tween these two fissures is fissured, but only slightly elevated
above the olfactory tract, and is continuous with the insular area.
The insula in this specimen is only slightly elevated and con-
tains but two gyres of which the more cephalic is the larger.
The fissures are simple and very shallow exeept the circuminsu-
lar at the cephalic end. The transinsular is not well marked
near the mesal margin. The insula is entirely concealed.

In 1878 Krueg (30, 325) said the insula was present in the
Hippopotamide. Chapman in 1881 (9, 144) said: ‘‘The

90 JouRNAL oF COMPARATIVE NEUROLOGY,

Sylvian fissure in my Hippopotamus is quite evident and within
it I noticed a rudimentary island of Reil.”’

THE INSULA IN THE CETACEA.

Fig. 35 represents the insula of the porpoise (Globzoceph-
alus melas). In this specimen the insula is completely con-
cealed within the Sylvian fissure and the plane is parallel to
the lateral surface. The area is proportionally very large but
at the same time very flat and there is no evidence of a fis-
sure homologous with the transinsular and no approximation to
a pole. This specimen shows at least nine gyres, three of
which are subdivided by fissures which are deepest ‘near the
circuminsular. It is not known that any of the fissures of this
area are constant. In 1879 Spitzka (53) says the ‘‘insula in the
porpoise has four times as many convolutions and is twice as
large as that in man and is completely covered by the opercu-
The same author also says that one

”

lum and temporal lobe.
specimen in his posssession has either thirteen or fifteen gyres.
Wilder [lecture] said that the gyres of the porpoise insula ex-
ceed in number those of any other mammal observed by him,
but they are smaller, and he concluded that ‘‘in combined
elevation and fissuration, the insula reaches its highest devel-
opment in man.”’

Ziehen (31, 110, 1889) says of the white whale (Beluga
lucas), ‘‘ The area between the fissura circularis interna and the
fissura circularis externa, probably also a large part of the cov-
ered portion of the floor of the Sylvian fossa ought to be desig-
nated as insula.”” Of the Sylvian fissure in W/egaptera boops, he
(31, 125) says ‘‘Ursprung vom aus der Fissura Rhinalis An-
terior. Die MHaupttheil bildet die obere Begrenzung des
Inseldreiecks.”’

None of the representatives examined of the remaining
orders show any evidence of an insula.

CiarKk, Comparative Anatomy of the Insula. fo

SUMMARY.

1. Neither the insula nor the claustrum is constant among
mammals.

2. The insula is present in the Primates, Carnivora, Pro-
boscidia, Ungulata and Cetacea. It is apparently absent in the
Cheiroptera, Insectivora, Rodentia, Sirenia, Marsupialia and
Monotremata.

3. The claustrum may include parts of areas other than
the insula.

4. Theinsula and the claustrum may generally be consid-
ered as parts of the same cortical area; the claustrum may be
present without the insula; both may be present or both may be
absent.

5. The apparent absence of the claustrum when the in-
sula is present indicates that, relative to the surrounding areas,
the insular cortex is farther laterad than in those specimens
where it is so demarcated. The myelinic fibers of the sur-
rounding areas then pass wholly entad of the insular cortex.

6. The insula is, in general, a convoluted area.

7. The insula is sometimes a subarea but quite often it is
exposed upon the lateral surface of the cerebrum.

8. The exposure of the insula may indicate either its own
excess or the deficiency of the overlapping adjacent parts.

O:)) bhe® eytes of the overlapping areas are always _ inter-
calated with those of the insula.

10. Individual and lateral variations upon this area are
numerous and marked and are probably due in part to growth
in an enclosed space.

11. The insula in the Primates, the Carnivora, some of
the Ungulata and Cetacea and perhaps others is a subarea or sub-
gyres at the bottom of the Sylvian fissure.

12. The insula frequently is almost wholly within the Syl-
vian fossa. This condition is not believed to indicate in any
way a different relation to the parts entad but rather a more uni-
form development of the insula and the surrounding areas so
that no lateral overlapping has taken place and hence the ven-
tral end of the Sylvian fissure remains unclosed as a fossa,

92 JOURNAL OF COMPARATIVE NEUROLOGY.

13. The insular area, in the more generalized types of
mammals, at least, does not belong primarily to the rhinenceph-
-alon as held by Turner in regard to the human brain.

14. The fissured surface which is usually the dorsal in the
raccoon, the deer, the burro, the horse, the pig, and the sheep,
is homologous with what appears on the lateral surface of the
insula of the Primates, most of the Carnivora and some others.

15. The variation in the plane of the fissured surface of
the insula is probably due to some peculiarity in the develop-
ment of the brain stem.

16. Fissures on the insula are less deep and more open
than on the surrounding parts; this is probably due to growth
under pressure of overlapping parts.

17. The lack of conformity between the Sylvian and
transinsular fissures both in position and direction is probably
due to the mechanical effect of growth in an enclosed space by
which a displacement of the Sylvian has occurred.

18. The difference in the relative mass of the insula, its
position, plane and relative development in the camel and deer
is very much greater than might be expected in two animals so
closely related.

19. The difference between the insula of the bear and the
raccoon is very striking.

20. It is noteworthy that the cat (7. domestica) and oce-
lot (/. pardalis) and the lynx have no insula, while the panther
(#. concolor) and the lion (/. /eo) have a rudimentary one. °

21. The overlapping of the insula in the human brain,
and presumably in others, is not due to a cessation of growth
of the insula but to the more rapid growth of the surrounding
lobes and the rapid enlargement of the paracceles.

22. The apparent approximation to a pole in the horse is
noteworthy.

23. The primitive insula, if such exists, is a somewhat
elevated area of greater or less size surrounded by a circuminsu-
lar fissure and located in the Sylvian fossa or in the fissure if
the fissure is continuous with the rhinal.

CLARK, Comparative Anatomy of the Insula. 93

SYNONYMY—INSULA.

1. Central lobe.—The application of this term to the insula is objection-
able on account of its more common use in connection with a lobe of the cerebel-
lum and also because the adjective, central, is often applied to fissures and lobes
topographically related to the central fissure (f. of Rolando).

2. Convolutions placed between the fissure of Sylvius and the corpus
striatum (Vicq d’Azyr).

3. Circonvolutions supplementaires (Leuret and Gratiolet).

Entosylvian folds or tract (Owen).
s. Fifth lobe of the brain.
6. Gyri breves (Gall, Arnold).
7. Gyri operti.
8. Gyri unciformes (Eberstaller).
Opn elle:

10. Insel (Reil).

11. Insellappen.

12. Insula. This name takes precedence over all others, being the Latin
form of ‘‘Insel,’’ the name given by its first describer, Reil. The regular par-
onyms of insula as given by Wilder (22, 530-31) are English, insula; German,
Insel; French, insulé; Italian. isola.

13. Insula de Reil.

14. Insula del Reil.
15. Insular lobe.

16. Insula Reilii.

17. Insula Sylvii (Mingazzini).

18. Intersylvian convolutions (Owen).

19. Intralobular gyri (Quain).

20. Island of Reil (English Authors).

Zien wsolar

22. Limen insule.

23. Lobe central (see note under 1).

24. Lobe central de l’insula (see note under 1).
25. Lobe de l’insula de Reil (Broca).

26. Lobe intermediare.

27. Lobe moyen.

28. Lobettino centrale nel tipo pecorino (Tenchini and Negrini).
29. Lobo centrale (Gratiolet).

30. Lobo fondamentale (Lussana).

31. Lobo insulare (Lussana).

32. Lobule de l’insula.

33. Lobule du corps strié.

34. Lobule sous-sylvien (Broca).

35. Lobulo del corps striato.

36. Lobulo sotto-silvico (Tenchini and Negrini).
37- Lobulus centralis (see note under 1).

38. Lobulus corporis striati.

39. Lobulus fissuree Sylvii.

904 JOURNAL OF COMPARATIVE NEUROLOGY.

40. Lobus caudicis (Burdach).

41. Lobus insule.

42. Lobus intermedius s. opertus.

43. Lobus opertus (Arnold).

44. Lobus retractus.

45. Median lobe.

46. Minor intersylvian convolutions (Owen).

47. Quinto lobo delle cervello.

48. Reil’s island.

49. Stammlappen (Huschke),

50. Subsylvian fold (Owen).

51. Subsylvian lobe.

52. Subsylvian tract (Owen).

53. Versteckenlappen (Arnold).

54. Zwischenlappen (Arnold).

SYNONYMY—CLAUSTRUM.

I, Avant-mur.
2. Claustrum (Burdach).

3. External wall (Huguenin, Charcot).
4. Noyau rubané.
5- Nucleus teenizformis (Arnold).
6. Rampart.
7. KRempart.
8. Vormauer.
SYNONYMY—TRANSINSULAR FISSURE.
1. Fissura interinsularis (Eberstaller).
2. Hauptfurche der Insel (Eberstaller).
3. Inselfurche (Eberstaller).
4. Le grand sillon de l’insula (Brissaud).
5. Sulcus centralis insulze (Guldberg) 13.
6. Sulcus centralis Reilii (Turner).
= 7. Sulcus Insulee (Eberstaller). ¥
8. Transinsular fissure (Wilder).
SYNONYMY—CIRCUMINSULAR FISSURE.
1. Circuminsular fissure, (Wilder).
2. Fissura circularis.
3. Rigoles de ]’insula (Broca).
4. Sulcus circularis RKeilii (Schwalbe) 43.

BIBLIOGRAPHY.

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2. 1882. BOURNEVILLE et BONNAIRE. Lesion Ancienne du Lobule de
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CLARK, Comparative Anatomy of the Insula. 95

3. 1893. BrissAuD, E. Anatomie du cerveau de ’homme. Paris, Atlas
and Text.

4. 1888. Broca, PAuL. Memoires sur le cerveau de homme et des pri-
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5. 1889. BROWNING, WM. Vessels of the Brain. Ref. H’db’k, Med. Sct-
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6. 1890. BROWNING, WM. Vessels of the Brain. Ref. H’di’k. Med.
Scez., IX, 138-141.

7. 1819-1826. BurRpACH, KARL FRIEDRICH. Vom Baue und Leben
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§. 1879. CHAPMAN, HENRY C. On the Structure of the Chimpanzee,
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9. 1881. CHAPMAN, HENRY C. Observations on the Hippopotamus.
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10. 1892. CHAPMAN, HENRY C. Observations upon the Brain of the
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11. 1883. CHARcoT, J. M. Lectures on the Localization of Cerebral
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12. 1893. CLARK, TRAcy E, The Insula of the Pig. Jour. Comp. Neur.
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13. 1891. CUNNINGHAM, D. J. The Sylvian Fissure and the Island of
Reil in the Primate Brain. Journ, Anat. and Phys., XXV, pt. 1, 286-291.

14. 1891. CUNNINGHAM, D. J. The Development of the Gyri and Sulci
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15. 1892. CUNNINGHAM, D. J, Contribution to the Surface Anatomy of
the Cerebral Hemispheres. Cunningham's, Memoirs, No. 7, R. 1. Acad., Dublin,

16. 1786. D’AzyR, Vicg. Traité d’anatomie et de physiologie. ards.

17. 1887. EBERSTALLER, Oscar. Zur Anatomie und Morphologie der
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18. 1888. EBERSTALLER, OscAR. Noch einmal die Insula Reilii. Azar,
Anz ils 52.

19. 1885. FAmILIAntT, VicrortaA. Beitrage zur Vergleichung der Hirn-
furchen bei den Carnivoren und den Primaten. Sern.

20. 1886. FERE, CH. Traité elementaire d’anatomie médicale du systéme
nerveux, 79-87. aris.

20%. 1896. FIsH, PIERRE A. A Note on the Cerebral Fissuration of the
Seal (Phoca vitulina). Journ. Comp. Neur., V1, 15-18, 1 plate.

21. 1866. FLower, W. A. On the Brain of the Javan Loris (Stenops
javanicus). Zvansactions Zoological Soc., V, 103-110.

22. 1889. GAGE and WILDER. Anatomical Terminology. Ref. A’dd’h,
Med. Scz.. VIII, 5§15-537-

93. 1881. GIACOMINI, CARLO. Varieta delle circonvoluzioni cerebrali
del’uomo. Zorino.

24. 1884. GIACOMINI, CARLO. Guida allo Studio delle circonvoluzioni
cerebrali dell’uomo. Torino, 92-99.

96 JouRNAL OF COMPARATIVE NEUROLOGY.

25. 1887. GuLpBerGc, Gustav A. Zur Morphologie der Insula Reilii.
Anat. Anz., 11, No. 21, 659-665.

26. 1881. Hammonp, GRAEME M. Anew Cortical Centre. Medical
’ Record, March 19, Abstract in Scéence, April 16. Mew Vork.

27. 1886. HARTMANN, RoBERT. Anthropoid Apes. Mew York.

28. 1893. HerrRIcK, C. L. Recent Progress in the Comparative Anato-
my of the Nervous System. Ref. H’dd’k. Med. Scz., 1X, 669-690.

29. 1872. Huxtry, THos. H. A Manual of the Vertebrated Animals,
New York.

30. 1878. KRrueEG, JuLius. Ueber die Furchung der Grosshirnrinde der
Ungulaten. Zettschrift f. Wiss. Zool., XXXI, 297-345.

31. 1889. KUKENTHAL und ZIEHEN. Ueber das Centralnervensystem
der Cetaceen. Vergleichend-anatomisch und Entwickelungsgeschichtliche Untersuch-
ungen an Walthieren, Erster Theil. ena.

32. 1839-56. LrURET et GRATIOLET. Anatomie comparée du systéme
nerveux de l’homme et des primates. Tome II, 112.

38. 1871. LussANA e LEMOIGNE. Fisiologia dei centri nervosi ence-
falici. Padova.

34. 1877. Major, HERBERT C. The Structure of the Island of Reil in
Apes. Lancet, II.

35. 1877. Major, HERBERT C. The Histology of the Island of Reil.
Monthly Micoscopical Journal, July, XVIII, 14-21. London.

36. 1893. MARCHAND, FELIX. Die Morphologie des Stirnlappens und
der Insel der Anthropomorpben. /Jena, Monograph, 180 pp., 3 plates. Abstract
in Jour. Comp. Neurol., 1894, IV, p. cx.

37. 1864. MARSHALL, JOHN. Onthe Brain of a Bushwoman and on
the Brains of two Idiots of European Descent. Phzlos. Transactions, 501-508.
London,

38. 1872. MEYNERT, THEODOR. The Brains of Mammals. Stricker’s
Manual of Histology, 650-766. Translated by Buck, Mew York.

39. 1885. MEYNERT, THEODOR. Psychiatry. Translated by Sachs,
New York.

40. 1886. Mitts, C. K, Arrested and Aberrant Development of the
Fissures and Gyres in the Brains of Paranoiacs, Criminals, Idiots and Negroes.
Journ, Nervous and Mental Disease, XIII Nos. 9 and to.

41, 1888. MINGAZzINI, J. Ueber die Entwickelung der Furchen und
Windungen des Menschlichen Gehirns. Gzessen.

42, 1788. Monro, ALEXANDER. Observations on the Structure and
Functions of the Nervous System.

43, 1890. OBERSTEINER, HEINRICH. The Anatomy of the Central Ner-
vous Organs. Translated by Hill, Ph2/adelphia.

44, 1568. Owen, RICHARD. On the Anatomy of the Vertebrates, III.
London.

45. 1879. Panscu, ADOLF. Beitrige zur Morphologie des Grosshirns
der Saiigethiere. Morphologisches Jahrbuch, Fiinfter Band. Leipzig.

46. 1880. PARKER, ANDREW J. JMéedical Record, Jan. 10.

CLARK, Comparative Anatomy of the Insula. 97

47. 1804-6. ReIL, JoH. Curist. On the Sylvian Fissure and Insula, *
Archiv fiir Physiologie, 1X, 196.

48. 1879. RicHET, CHAs. Physiology and Histology of the Cerebral
Convolutions. Translated by Fowler. Mew Vor.

49. 1887. RoLiEston, H. D. Description of the Cerebral Hemispheres
of an Adult Australian Male. Journ, Anthrop. Inst. G. B. and I., XVII, 32-43.

50. 1893. SAcHs, HEINRICH. Vortrige iiber Bau und Thitigkeit des
Grosshirns und die Lehre. Breslau.

51. 1881. SCHWALBE, G. Lehrbuch der Neurologie. Zylangen.

52. 1879. SpitzKa, E.C. Report of N. Y. Neurol. Soc. Meeting.
Medical Record, May 25. New Vork.

53. 1880. SpirzKA, E.C. The Brain of a Porpoise, Medical Record,
XVII, 72, Jan. Mew York,

54, 1880-81. SpirzKA, E.C. A Remarkable Peculiarity of an Anthro-
poid Brain. Sctence, I, 25. Mew York.

55. 1882. Spitzka, E. C. On the Autopsy of Guiteau. Amer. Journ.
Neurol. and Psychiatry, 1, 381-392.

56. 1883. SpitzKa, E. C. Contributions to Encephalic Anatomy. Amer,
Journ. Neurol. and Psych., Il, 249-274.

57. 1889. Spitzka, E.C. Histology of the Brain. Ref. A’di’k Med.
Sc#., VIII, 164-189.

58. 1885. STARR, M. ALLEN. Diagnosis of Local Lesions of the Brain.
Ref. Hdb’k. Med. Sci., 1, 642-648.

59. 1889. TENCHINI e NEGRINI. Sulla Corteccia Cerebrale degli Equini
e Bovini. Parma. ;

60. 1858. TURNER, SIR WM. Convolutions of the Seal and Walrus,
Journ. Anat. and Phys., XXII, 566-568.

61. 1890. TURNER, SIR WM. The Convolutions of the Brain. Journ,
Anat. and Phys., XXV, 105-153.

62. 1887. WALDSCHMIDT, JULIUS. Beitrige zur Anatomie des Taub-
stummengehirns. Adlgemeine Zettsch. f. Psych. u. Psychische Gerichtliche Mea-
zcin, XLIII, 373-379.

63. 1886. WILDER and GaGE, Anatomical Technology, 2nd Ed. Mew
York.

64. 1889. WiLpER, BurTG. Brain, Gross or Macroscopic Anatomy.
Ref, Hdb’k. Med. Scz., VIII, 107-164.

65. 1893. WILDER, Burt G. Brain, Gross or Macroscopic Anatomy.
Ref. Hdb’k. Med. Sci., UX, 99-111.

66. 1894. WILDER, Burt G,. Exhibition of a Suicide’s Brain, with two
Pistol-ball Wounds. Remarks on its Fissural Anomalies. Journ. of Nervous
and Mental Disease, December, 1-4.

EXPLANATION OF FIGURES.

With the exception of figures 1, 2, 3, 4, 5, 6, 7, 8, 12, 17, 18, 19, 20, 21,
25, 31 and 34, all the figures were produced as follows: The specimens were
photographed natural size, with a vertical camera; from the photographs out-

* The exact title of Reil’s article is not known by the writer.

98 JOURNAL oF COMPARATIVE NEUROLOGY.

lines were traced also with the camera. Liability to distortion due to the eu-
largement of the parts of an uneven surface was materially reduced. Figures
I, 2, 3, 4, 5, 6. 7, 21, 25, 31, were photographed natural size and enlarged from
photographs or figures as indicated, with an enlarging apparatus. Figures 8,
17, 18, 19, 20 and 34 were photographed as stated and traced from photographs,
Fig. 12 was made from outlines traced from photographs of lateral views
before and after dissection.

ABBREVIATIONS.

art.—artery. p. of.—postoperculum,
circ. f.—circuminsular fissure. pretn.—preinsula.
c/.—claustrum. Preop.—preoperculum.
fi. olf. tr.—myelinic fibres of olfactory 7h. f.—rhinal fissure.

tract. subop.—suboperculum.
im.—insula. Sy. #.—Sylvian fissure.
of.—operculum. tr. f.—transinsular fissure.
P.—-Pole of the Insula. z. f.—zygal fissure.
postin.—postinsula. v. f.—vertical fissure.

DESCRIPTION OF FIGURES.

The numbers are the serial numbers of the Museum of Vertebrate Zoology
of Cornell University.

PLATE IX.

Fig. 1. UWateral aspect of the left half of the brain of a human fetus, size
and age unknown. 2278; x 1 (after Wilder, 68, Fig, 4760).

Fig. 2. Ventral aspect of the left cerebrum of a human fcetus, size and
age unknown. 1820; x 1 (after Wilder, 64, Fig. 4782).

Fig. 3. Wateral aspect of right human insula, age and sex unknown, adult,
1805; x I. The insula was exposed by cutting away the surrounding lobes
down to the level of the circuminsular fissure, thus exposing the medicornu and
hippocamp. The three eminenges 1, 2 and 3 belong to the postinsula. The
fissure marked 4 is too sharply outlined near the ventral end. At the point in-
dicated it is a mere vasal furrow and does not communicate with the Sylyian
fissure ventrad.

Fig. 4. Lateral aspect of right human insula, age and sex unknown,
young, 1823; x 1. This preparation shows the branches of the medicerebral ar-
tery as it divides over the surface of the insula. The largest branch lies in the
transinsular fissure for about two thirds of the distance across the insula, then
leaves this fissure and bends caudo-dorsad as if towards the Sylvian. There is
also shown a tendency toward the demarcation of an eminence similar to that
shown in Fig. 3.

Fig. 5. Dorso-lateral aspect of the right human insula, age 37 years,
male, 376; x 1. A nearly normal insula except for the unusually élevated pole,
P. The short furrow cephalad is represented too deep and too narrow.

Fig. 6. Caudal aspect of a transection of the left cerebrum of man, after
Wilder (64, 4732)- Shows the relation of the insula to the claustrum, the brain
stem and operculums.

CrLarK, Comparative Anatomy of the Insula. 99

PLAT EHX.

fig. 7. Lateral aspect of the right insula of chimpanzee, supposed age 4
years, female, 265; x 1. The operculums have been cut away.

Fig. 8. Lateral aspect of the right insula of a macaque monkey, age and
sex unknown; x I. The lateral portion of the cerebrum was removed to the
level of the ventral half of the circuminsular fissure. The remainder of the
insula was exposed by cutting a groove parallel with the Sylvian fissure.

fig. g. Lateral aspect of the left insula of a seal (Phoca vitulina); x 1.
Operculums cut away. The black areas at the dorsal and ventral ends indicate
broken surfaces where the parietes were removed, and are too black.

fig. ro. Lateral aspect of the left insula of a panther (#elzs concolor), fe-
male, 18 years old, 309; x 1. QOperculums cut away.

fig. zr. Lateral aspect of the right insula of an adult raccoon (Procyon
Jotor), male, age unknown, 2031; x I. The overlapping portions have been re-
moved.

fig,712, Diagram of the same, showing the relation of the Sylvian and
transinsular fissures.

fig. 13. Lateral aspect of the right insula of a Thibet bear (Ursus thibet-
zanus), male, age at least 5 years; 645; x I. Shows well the relation of the
transinsular and Sylvian fissures.

fig. 14. Lateral aspect of insular region of a dog (cross between French
poodle and Skye terrier), age more than 18 years, sex unknown, 166; x I.
Shows the exposure of the insula before dissection.

Fig. 15. Lateral aspect of the insula of the same with the operculums cut
away; x 1%.

Fig. 16. Lateral aspect of the right insula of a dog (Canis famzliarts), age
unknown, probably adult, male; x I.

fig. 17. Outline of a section of the above looking dorsad; x1. The
dotted brace indicates the extent of the insula.

PLATE XI.

fig. 18. Transection of the cerebrum of a dog (C. familiaris), male, age
a few weeks, 3124; x 21%. Section made according to Weigert’s method, after
hardening the brain in 3% and 5% bichromate of potassium, imbedded in collo-
dion and cut in oil; differentiates alba and cinerea.

fig. 7g. ‘Transection (Weigert) of a portion of the left cerebrum across the
Sylvian fissure of a cat (Hels domestica), age and sex unknown; x 2%.

Fig. 20. Transection (Weigert) of a portion of the right cerebrum across
the Sylvian fissure of a skunk (Mephitis mephitica), age atid sex unknown; x 2%.

fig. 34. Transection of the right insular region of a sheep (Ov7s aries),
age and sex unknown, looking cephalad ; x 4%.

PLATE XII.

Fig. 21. Lateral aspect of the left insula of an elephant (Z/ephas zndicus),
age unknown, female, 2181; x 1. Overlapping portions have been dissected
away,

100 JOURNAL OF COMPARATIVE NEUROLOGY,

Fig, 22. Lateral aspect of insulaof a camel (Camelus dromedarius), male,
age 15 minutes, 2122; x I. The shaded portion at the right of the insular area
is a broken surface and does not belong with the insula.

Fig. 23. Lateral aspect of the left insula of a deer (Cariacus virginiana),
male, age unknown, 961; x I.

Fig. 24. Lateral aspect of the left insula of a Mexican burro (Zguus
asinus), male, age unknown, 2259; x I.

Fig\25. Lateral aspect of the left insula of a horse (#guzs caballus), male,
adult, 2095; x I.

Fig. 26, Wateral aspect of the left insular region of a cow (Bos taurus),
adult, sex unknown, 3408; x I. Shows exposure of the insula.

Fig. 27. Lateral aspect of the right insular region of a cow (Bos taurus)
adult, sex unknown, 3408; x I, Shows exposure of insula before dissection.

Fig, 28. WDorso-lateral aspect of the right insula of the same, exposed by
cutting away the operculums.

PLATE XIII:

Fig, 29. Dorso-lateral aspect of the left insula of the same after dissection.

Fig. 30. Lateral aspect of the cephalic half of the left cerebrum of
a cow (Bos taurus), after Turner (61, Fig. 26). The fissure marked 5S, which
Turner considers as the Sylvian, is the transinsular; the Sylvian is directly
dorsad.

Fig. 31. Lateral aspect of the left cerebrum of a Malayan tapir (Zapzrus
malayanus), age and sex unknown, 2123; x 1. Dorsal portion of the cerebrum
not shown ; insula exposed by removal of overlapping parts.

Fig. 32. \ateral aspect of the left cerebrum of a sheep (Ov¢s artes), sex
and age unknown, probably young; x 1. Shows the insula exposed before
dissection.

Fig. 33. Dorso-lateral aspect of the right insula of a sheep (Ov¢s arzes),
sex unknown, probably young; x 1. Insula exposed by cutting away dorsal
overlapping portions.

Fig. 34. See description under Plate XI.

Fig. 35. Lateral aspect of the insula of a Porpoise (Glodicocephalus melas),
female, adult, 670; x 1. Insula exposed by cutting away of the operculums.
Sy. f. designates the basisylvian fissure between the temporal and frontal
lobes.

REVIEW OF THE GOLGI METHOD.

By OLIVER S. STRONG.

The advent of the Golgi method in nerve histology has so
ereatly enlarged our knowledge and altered our conceptions of
the structure of the nervous system in many respects and the
method, or methods, itself has such well defined peculiarities that
it has been thought that a general review of it, from the techni-
cal side would be of interest and perhaps of use, especially in
view of the very considerable number of investigators now
employing it.

The review does not aim at any originality of treatment
but is simply a compilation from available literature of its vari-
ous modifications and applications. It may be stated that it
does not include Golgi’s arsenic-gold chloride method nor even
the application of the bichromate-silver methods to the structure
of medullated nerve fibres.

It has seemed most appropriate to begin the review with a
translation of the technique of Golgi’s methods as given by Golgi
himself, principally in his work ‘‘Studi sulla fina anatomia degli
organi centrali del sistema nervoso,” pp. 181-208. The trans-
lation is made, however, from the German edition of Golgi’s
works ( ‘‘ Untersuchungen iiber den feineren Bau des centralen
und peripherischen Nervensystems,” pp. 169-182, translated by
R. Teuscher). Golgi’s own account of the technique is still
the most complete nor does it seem to be by any means univer-
sally understood how completely Golgi worked it out and how
largely we owe not only the discovery but also the development
of the method to him. It is for these reasons as well as for the
many valuable hints contained therein that the translation of this
rather extensive account of Golgi’s is here given.

‘The particular methods to which I owe my most note-
worthy success are the following: (1) The method of black-
staining by successively treating the pieces (of brain tissue)

102 JOURNAL OF COMPARATIVE NEUROLOGY.

with bichromate of potassium or ammonium and silver nitrate.
(2) The method of the successive action of a mixture of osmic
acid and bichromate and of silver nitrate. (3) The method of
the combined action of bichromate of potassium or ammonium
and bichloride of mercury. (The stain appears black by trans-
mitted, metallic white by reflected light).

‘“(1) Zhe method of the combined action of bichromate of
potassium and of silver nitrate. In the series of methods which
I have especially employed this is, in a manner, the fundamen-
talone. The others are only variations of this, devised to
shorten the time of the preliminary treatment, to make the
preparations more stable, to vary the results in various ways,
especially to obtain a greater extension of the reaction and to
cause the reaction to affect one or another species of the ele-
ments or a part of them.

‘‘T consider it to the point to call attention to the fact that
the procedure of the microscopical technique which I will de-
scribe, although it rests essentially upon the action of silver ni-
trate, has nothing in common with the usual method of staining
the intercellular substance of endothelium, epithelium and con-
nective tissue brown or black. In the latter method dilute so-
lutions of silver nitrate are applied immediately to the fresh
tissue, exclusively to the surface of membranes or membranous
tissues of slight thickness (aponeurotic plates, substance of the
cornea, intima of vessels) and light exerts an important influ-
ence upon the reaction whereby the blackening of the combina-
tion which the silver salt forms with the ground substance is
brought about. With my method the light has nothing to do
and the reaction takes place through the gradual penetration of
the silver salt into more or less voluminous pieces which have
been previously treated with bichromate. The black-staining
of the various elements composing the nervous tissue results
froma reducing action which the elements themselves exert,
under the influence of the bichromate, upon the silver salt.

‘‘The procedure necessary to bring about the black-stain-
ing of the elements of the central nervous system consists essen-
tially of two parts.

StronG, Review of the Golgi Method. 103

‘‘(a) Hardening of pieces in a solution of potassium bt-
chromate.

‘<(b) Immersion of the hardened pieces in a solution of silver
nitrate.

‘‘ (a) Hardening in bichromate. Although there are no es-
pecial rules for the hardening other than those which must usu-
ally be followed to obtain a good uniform hardening, yet it is
this part of the process which requires the most care. This is
the more so because the time necessary to harden the pieces to
the degree required for the action of the second reagent varies
very considerably according to different circumstances and espe-
cially according to the temperature.

‘« For the first immersion of the pieces, I use either a sim-
ple two per cent. solution of potassium bichromate or the usual
formula of Miller. (The reagents should be pure.) There
must be an abundant quantity of fluid in proportion to the quan-
tity of pieces to be hardened.

‘The part of the brain or spinal cord to be treated is cut
into tolerably small pieces (about 1 to1% ccm.). It is important
that the pieces be fresh; the fresher the pieces, the better the
results. It is well to use, preferably, the brains of animals just
killed, yet satisfactory results can also be obtained 24 to 48 hours
after death. It is hardly necessary to say that the pieces must
be cut regularly and in definite directions (according to the part
to be studied) so as to permit orientation as to the part and the
location of, the elements in the future study.

‘« That the hardening may proceed with some rapidity and
be uniform, it is well to successively increase the concentration
of the fluid, raising the quantity of bichromate from 2g to 2%,
3, 4and 5%.

‘Whether the fluid is increased in strength in hardening
the pieces, or remains the same strength, it is always necessary
to change it from time to time to avoid the formation of moulds
which, as is well known, develop abundantly in bichromate so-
lution when the pieces are to some extent neglected. For the
same reason it is advantageous to place in the vessels with the
pieces a small quantity of some substance which will prevent

104 JOURNAL OF COMPARATIVE NEUROLOGY.

the growth of hyphomycetes, as camphor, salicylic acid, ete.
The most important point and at the same time the most diff-
cult to determine in order to obtain good results with this meth-
od is the length of time during which the pieces must be kept
in the bichromate solution before one passes on to the second
part of the process, the reaction with the silver nitrate.

‘‘The proper duration of immersion for the pieces to ob-
tain that degree or particular kind of hardening which is best
fitted to secure, when they are laid in the silver solution, a fine
and diffused action upon the various elements of the nervous
system varies according to various conditions. These are the
strength of the fluid, the condition of the pieces, the quantity
of fluid, temperature and, consequently, the time of the year.

‘‘ The differences arising from the strength and quantity of
the fluid may be eliminated by paying strict attention to the
strength of the fluid, by using covered vessels and preserving
the same ratio between the number of pieces and quantity of
fluid.

‘The influence of temperature upon the results of the re-
action is more important, indeed practically all the uncertainties
of the method depend upon this. For example, to mention
extremes, good results (which, with the progressive changes, of
which I shall speak later, continue to appear and extend) can be
obtained in the warm season after an immersion of 15 to 20 days
and seldom after 30 to 40 or 50 days; on the other hand in the
cold season good results are scarcely obtainable after,an immer-
sion in bichromate of less than 1 to 1% months. The reaction
(with the progressive accompanying changes) may then con-
tinue to manifest itself for 2, 3 or 4 months, provided, ‘of course,
the pieces are preserved according to the rules given above. It
is almost superfluous to say that during the gradual change from
the warm to the cold season and vice versa corresponding
changes in the appearance of the reaction take place. It is not
easy to remedy these temperature changes, especially because
these changes of environment are united with the other causes
of uncertainty mentioned and so act that observations made
upon one series of pieces, never agree closely with those made

STRONG, Rewew of the Golgt Method. 105

upon another series. A warm chamber, of which I shall speak
later, cannot bring about the accuracy sought for.

‘‘The surest means of remedying these inconveniences is
the persevering repetition of the process, i. e. one must have a
good number of pieces available, bring several from time to
time into the silver solution and then ascertain whether they are
in the desired condition. If a good reaction has taken place,
one continues the trials at regular intervals in order to obtain
all the stages of the reaction, which constitute an advantage of
this method. It is self-evident that the different trials must fol- .
low each other at intervals differing according to the time of the
year. Inthe warm season, when the requisite hardening is
reached much earlier, the trials must follow each other more
quickly ; in the cold season, on the other hand, when the de-
sired hardening is first reached after a month, the trials can be
made at intervals of 8 to 1o days beginning with the time when
one, according to my direction, has ground to assume that the
tissue has begun to enter the desired condition.

‘© (6) Transference of the hardened pieces into the solution of
silver nitrate. Although the various conditions of which I have
spoken make it impossible to state with complete accuracy for
how many weeks or days the pieces must be brought from the
bichromate into the solution of silver, this is no ground for con-
cluding that the method is subject to excessive uncertainty. All
difficulties are overcome and one can be absolutely sure of al-
ways obtaining excellent results by the simple procedure of
steadily extending the trials with every series of pieces. The
difficulties are thus very like those which one encounters in the
employment of all other impregnation and imbibition processes,
not excepting the simple carmine staining, in which, as is well
known, one only reaches quick and certain results after repeated
trials when he has learned to know the nature of the staining
fluid and of the pieces to be stained.

‘‘T usually employ a 34 % silver solution; yet I will remark
that it is not necessary to adhere closely to this formula to ob-
tain the reaction. A slightly stronger or weaker solution does
not affect the result. I will also-add that a slightly weaker so

106 JOURNAL OF COMPARATIVE NEUROLOGY.

lution (%%) appears to be somewhat more suitable (giving
finer results though confined to fewer elements) so long as the
pieces have not yet reached the complete hardening, while a
slightly stronger solution (to 1%) appears better adapted for
pieces whose hardening has progressed a little too far.

‘« The quantity of the silver solution to be used must vary
with the number and size of the pieces to be laid therein, but
must be relatively abundant. For two or three pieces of about
1 ccm. I use about half a beaker (dzcchzere) of the fluid.

‘‘The moment the pieces are brought from the bichromate
into the silver solution a copious yellowish precipitate of silver
chromate results. The formation of this precipitate takes place,
of course, at the expense of the strength of the fluid inasmuch
as through the formation zz /oco of the insoluble precipitate a
more or less considerable portion of the silver salt is deposited.
This changes, naturally, the relation (osmotic as well) between
the fluid which should penetrate into the piece and the inner
portions of the piece. It might happen that the whole or the
greatest part of the silver would be precipitated from the solu-
tion, which would result in the more or less complete absence of
the reaction. To avoid this mishap it is expedient to first wash
the pieces in which the reaction is sought in a weaker solution
of silver. I use for this purpose, from motives of economy,
silver solutions which have already been used on other pieces
without the silver having been fully neutralized. When this
washing has been continued until the pieces cause no more pre-
cipitate when brought into a clear solution’ they are finally
placed in the fluid of the proper strength. From there on the
preparation usually requires no especial attention, for if the
solution is present in copious quantity it is sufficient to let the
fluid penetrate into the interior of the piece. Yet it is well to
consider that it is sometimes expedient, with pieces thoroughly
saturated with bichromate through a long sojourn therein to

1Several minutes should elapse to test this, inasmuch as the discoloration of
the silver solution by the reddish precipitate sometimes takes place rather slow-
ly, both in this and in the rapid method.— Writer.

STRONG, Review of the Golgi Method. 107

change the solution for a fresh one after the pieces have been
in the first solution 6 to 8 hours. This must be done whenever
the fluid assumes a yellow color, which shows that the silver
nitrate is neutralized. In this case the reagent can no longer
possess the necessary strength to penetrate to the interior of
the pieces.

‘‘T have already said that this reaction, through which
the black staining of the elements is brought about, has nothing
in common with that which stains the intercellular substance
under the influence of light. I now need to add that it is en-
tirely the same whether the pieces in our method are kept in
the light or in the dark; the reaction which is brought about
through the gradual penetration of the silver into the interior of
the tissue takes place equally well in both cases, The only rule
relating to keeping the pieces in the silver which experience has
shown to be in some manner useful is that they should be kept
in winter in a well-heated room. I place the vessel on a table
which is not far from the stove of the laboratory.

‘«The pieces must remain, asa rule, in the silver solution
for 24 to 30 hours, in exceptionable cases 48 hours. The
period of 24 to 30 hours must form the rule although,
when the time of hardening has been correctly hit upon, the
reaction may be well advinced in 2 to 3 hours. In such
cases one may say that the reaction begins immediately, at
least in the superficial layers, to extend gradually deeper
with the deeper penetration of the fluid. In the exception-
al cases when it is best to leave the pieces 48 hours and
longer in the nitrate solution and where it is well to change the
solution a second time, one must regulate his procedure by the
results of a microscopal examination of some superficial sec-
tions from which the condition of the reaction may be inferred.
Moreover one can perceive from the yellowing of the fluid,
whether the reagent is nearly neutralized.

‘« As for the rest, it is to be remarked that an indefinite
sojourn of the pieces in the silver solution lasting days, wecks
or even months is in no way injurious to them; on the contrary

108 JOURNAL OF COMPARATIVE NEUROLOGY.

this is a suitable means of preservation for pieces destined for a
particular investigation of long duration.

‘‘One of the most interesting peculiarities of the process
which I here describe consists in the fact that, while the brown-
ish black stain acts quite similarly upon all elements of the
nervous tissue (various kinds of ganglion cells, nerve-fibers,
elements of the neuroglia and walls of vessels), yet in reality
the staining of all these at one time forms an exception, i.e.
when the elements are in a certain state of hardening which one
only happens upon accidentally in a great number of trials. As
a rule the reaction appears only partially, i.e. it affects only one
or another layer with gradations and combinations which one
may term endless.

“This peculiarity does not detract from the method, but
is rather among its advantages, for if the reaction affected all
kinds of elements at the same time there would evidently arise
such an inextricable confusion that it would be impossible to
orient oneself in respect to the locations and relations of the in-
dividual parts. When, for example, in one preparation the
the cells especially are stained black, in another principally
the neuroglia together with the vessels and some groups of
nerve cells, it is evident that one can by the comparison of
many preparations obtain a general view of the various pecu-
liarities of the arrangement and relations to each other of the
individual species of elements and of the connection of the
structures of various regions. y

‘‘ This is so much the more the case since these combina-
tions and gradations also appear in certain layers and different
zones into which one is accustomed to divide different regions
of the nervous system. In the cortex, for example, the reaction
appears, with the various combinations above mentioned, some-
times in the superficial or middle, sometimes in the deep layers.

«© A law undoubtedly exists governing the manner of de-
velopment of the black stain and the succession of the reaction
among the various kinds of elements and it would be interest-
ing to learn to know this so.as to be able to bring about one or
another result at will; but it is extremely difficult, if not im-

STRONG, Review of the Golgi Method. 109

possible, to attain this. This difficulty will be readily compre-
hended when one reflects that the diversity of results is brought
about not only by the conditions given already but also by the
unequal hardening action of the bichromate so that the individ-
ual layers of the pieces are in different conditions. In the
individual pieces the degree of hardening may increase from
center to periphery so that a number of the above combina-
tions and gradations may appear in one piece.

‘‘The following approximate rule, however, may be accept-
ed for the way the reaction enters the various elements of the
nervous tissue when a number of similar pieces are successively
subjected to the action of the silver nitrate. There stain in the
following order:

“1, The bundles of nerve fibers. At the same time with
the staining of these fibers some scattered ganglion cells which
lie dispersed in the gray matter appear.

‘‘The staining of the nerve fibers at the beginning shows
little delicacy, the reaction being, so to speak, tumultuous, but
gradually gains in fineness with progressive hardening (always, how-
ever, after a more or less brief period of time). Then the individual
fibers (axis-cylinders) composing the bundles can be well seen
and also individual fibrillae streaming from the bundles, the finest
details of whose course and branching can be seen at a glance.

‘°2. The ganghon cells. VYhe ganglion cells of the su-
perficial layers always stain first (e. g. in the cortex the small
cells of the peripheral zone), but at the same time with them
also some cells irregularly scattered in the inner layers. As the
reaction progresses it affects the cells rather than the fibers
and the tendency is for the stain of the cells to become more
general and to extend from the periphery inwards. Then,
too, while the reaction is becoming more complete among the
cells of the deeper layers it becomes always more limited among
those of the superficial layers.

‘*With the cells as with the fibers the reaction is at first
coarse and little fitted to bring to view certain interesting de-
tails. For example, the nervous process is not stained at first
to any great extent and usually only a short piece of it is to be

110 JOURNAL OF COMPARATIVE NEUROLOGY.

seen so that neither its course, direction nor its few or numerous
branches can be perceived. With the gradual progress of the
reaction the nerve cells are displayed more clearly and the finest
subdivisions of their protoplasmic as well as their nervous pro-
cesses appear.

“©3, Cells of the icurogha. An interesting reaction oc-
curs in the cells of the neuroglia; it may be said that it takes
place in pieces suitably hardened in bichromate from the begin-

ning of the phase to the end. In fact at both the time when
~ the fibers predominate and when the cells predominate individ-
ual neuroglia cells or groups of them are to be seen showing the
characteristic reaction of the silver nitrate (coffee-brown or yel-
_lowish). Besides, with this species of element the reaction only
becomes fine and diffused in a somewhat advanced period of
hardening so that their typical form and relations are plain.
The reaction in neuroglia cells takes place for a long time be-
yond the time favorable for staining nerve cells.

The finest reaction for the nerve cells, especially for the
nervous processes, occurs at a somewhat advanced stage
of hardening, namely when, with the advance of the re-
action among neuroglia cells, it is limited among the gan-
glion cells. It is precisely among isolated blackened cells
that the stain of the individual functional (axis-cylinder)
processes is finest; one can observe the smallest details of
their course and branching. I must again recall that the reac-
tion must be produced in a series of pieces which have consecu-
tively received suitable treatment in order to learn to know all
its phases.

‘« After we have so circumstantially laid down the funda-
mental rules of procedure, it would be superfluous to go into
particulars about the differences obtaining between the different
provinces of the central nervous system (the cortex cerebri, the
so-called ganglia of the base, the cerebellum, the spinal cord).
I only remark here that, under similar conditions, pieces from
the cortex reach in bichromate the suitable state of hardening
somewhat sooner that than those from the cerebellar laminae,
that the latter reach it a little later than pieces of the spinal cord

StronG, Review of the Golgi Method. III

and that finally the so-called ganglia of the stem reach the prop-
er hardening still somewhat later than the parts named.

‘‘A last remark. When the above-described peculiarities
of the process are considered, it is intelligible how it often hap-
pens that the reaction appears only in one part of the piece.
For example, it is absent in the superficial layers, where there
is, aS a matter of fact, more often than otherwise only an irregu-
lar precipitate, and is present in the interior or vece versa. One
must remember this and when, very likely, the first sections
made near the surface show nothing of interest one must not
thereupon conclude that the reaction has failed, for it often hap-
pens that such preparations, in which only single, isolated cells
are stained, are among the most instructive for details of the in-
dividual elements.

“« Tyeatment and Preservation of Preparations. Whether
the black stain has turned out so that the piece is worth keep-
ing for further investigation can be ascertained by means of trial
sections examined in glycerine or in the reaction fluid itself.
Then one must provide for the preservation of the piece and the
microscopical sections. Although it is certain that a longer so-
journ in the silver solution does no harm whatever and that such
a sojourn may serve as a means of preservation, yet is expedi-
dient, in order to have the pieces ready for further treatment, to
transfer them to pure commercial alcoho]. This not only serves
to harden the tissue farther but also to free it from the silver
nitrate which, as I shall mention below, is very injurious to the
preservation of the microscopical sections. To accomplish the
latter the alchol should be changed two or three times till it re-
mains transparent for a number of days after the piece is brought
into it. In this way the pieces can be kepta longtime. I
have kept them for about nine years in this way and can obtain
from them, when I wish, preparations as clear as those obtained
from them shortly after their preparation.

‘«The further treatment of the microscopical sections cor-
responds essentially with the usual procedure in obtaining
anhydrous preparations except for some peculiarities necessary to

112 JOURNAL OF COMPARATIVE NEUROLOGY.

overcome some difficulties in the way of securing stable
preparations.

‘«The sections, before they are permanently brought into
gum damar or Canada balsam, must first be treated successively,
according to the classical method, with absolute alcohol and
some clearing fluid. Each of these steps requires an especial
care not necessary with ordinary preparations:

‘*(a) Treatment with absolute alcohol. The only rule to be

' especially noticed here is that the sections must be very care-

fully dehydrated by bringing them into three or four changes
of pure absolute alcohol. This is the only principal rule in or-
der to obtain a long preservation, for the more accurately and
carefully the dehydration is carried out, thereby freeing the
tissue from the last trace of silver nitrate, the more one can rely
upon the preparations remaining clear a long time.

‘« (6) Clearing. The sections to be mounted must first be
brought, for clearing, from absolute alcohol into creosote,
where they remain some minutes, and then into turpen-
tine. In the latter they can remain a long while. The selec-
tion of these two substances and their consecutive use is another
aid to securing a long preservation. Among many other sub-
stances tried for clearing I have also found oleum origani' for
my method very useful, but I have found no sufficient ground
for abandoning the first mentioned fluids. The sections usually
remain in turpentine only 10 to 15 minutes but may remain
there longer.

‘«(c) Completion of the microscopical preparations. For per-
manent preservation the sections are brought from turpentine
into damar which, after many comparative tests, I have found
better adapted for this purpose than Canada balsam. I must
here call attention especially to a peculiar treatment of the sec-
tions ; contrary to the usual custom, I do not cover the prepar-
ations with a cover glass. When the sections are covered in
the usual way with a cover glass, they begin after a time to turn

‘This oil, followed by washing in xylol instead of turpentine, is pre-
ferred by the writer.

StronG, Review of the Golgt Method. 113

yellow (owing toa second impregnation which takes place),
then the outline of the stained cell elements become obliterated,
the whole tissue becomes opaque and, after a period of from
two or three months to two years, the preparations, with few
exceptions, become useless. On the contrary they may keep
a long time thanks.to the repeated washing, of which I have
spoken, and especially to the mode of mounting without a cover
slip ina layer of damar. I can now state that the earlier la-
mentable disadvantage that preparations made by my method
soon spoiled is now almost completely remedied. I have many
preparations made by me nine years ago which have not yet lost
their original clearness.

‘‘Tf the good preservation appears menaced by an incipi-
ent yellowing, another longer bath, on the slide, in turpentine
will restore transparency and freshness to the preparation.

‘‘T have found it convenient to employ for this kind of
mounting a special wooden slide with a square opening in
which, by means of a groove, a glass plate (a cover slip of
somewhat greater diameter than usual) is fitted and stuck fast
with a solution of shellac in alcohol. This serves as a slide and
the section adheres to it by means of the damar.

‘‘This kind of slide not only enables the section to be ex-
amined from both sides but also has the advantage of prevent-
ing dust from fouling the object, to which this kind of mount
would be especially exposed. To accomplish this it is only
necessary to turn the side of the slide with the section down-
wards as soon as the damar is hard enough, or to pile the prep-
arations on top of each other.

“‘T further remark that it is wise to shield the objects
from the influence of light ; still this precaution is not entirely
necessary if the repeated washing has been carefully performed.
After fulfilling these conditions, I might expose preparations
for days to the sun’s rays without injury to them.

‘‘ This is not the place to lay stress upon the value of the
results which can be attained by means of this method. The
figures accompanying this work demonstrate it sufficiently.
They display the forms to be observed in the preparations with

114 JOURNAL OF COMPARATIVE NEUROLOGY.

a fineness not only not exaggerated but inferior to the natural ob-
ject. I will here only bring forward the disadvantages of the
method, in order to give the means by which they are to be
avoided, The long time between the placing of the pieces in
bichromate and the appearance of the reaction (it not infre-
quently happens that in consequence of this the pieces are for-
gotten), the uncertainty about the extremely variable time re-
quired to reach the proper hardening, the different conditions
in which individual layers of the same piece are found, all these
are disadvantages whose removal would be desirable.

‘“‘T have sought by expedients to change my method in
one way or another in order to secure greater certainty and ac-
curacy in the results. Among the means tried by me I pre-
sent the following which have yielded me a certain advantage.

‘«(a) Injections of bichromate (solution to 2% %.)' It must
be abundantly and constantly applied so that the whole paren-
chyma of the part to be investigated is fully and uniformly
penetrated by the hardening fluid. The fixation of the elements
by the reagent, where possible, before the slightest post mortem
change can take place is of the highest importance in securing
a very delicate reaction. The action of the injection consists
principally in giving a uniform hardening, furthermore in pre-
venting, very likely, a slight post mortem change in the in-
terior of the piece and finally in abbreviating the sojourn in
bichromate.

‘Tf ITmay draw a conclusion from some especially suc-
cessful reactions accomplished in this way, I must declare that
the injection is in these various respects actually of consider-
able advantage. Some other experiments, not yet very ex-
tended, have convinced me that a favorable influence is exerted
in the same way by injecting, not a simple solution of bichro-
mate, but one with gelatine added (244% bichromate, 100 cc. ;
dry gelatine, which is dissolved in the usual way, 5 to 6 grams).
This procedure appears to me especially fitted to give the

! A stronger solution would probably be better, inasmuch as it undergoes
dilution in the tissue.— Writer.

STRONG, Review of the Golegt Method. 115

pieces in less time that particular hardening most favorable to
the best reaction with silver nitrate. I mention, for example,
a case where I have obtained graduated reactions of surprising
fineness on pieces 15 to 30 days after they were placed in bi-
chromate at a temperature of 15° to 20° C. (in autumn), the
pieces having been subjected to the above treatment.

‘The injection is performed in the usual way (with a sim-
ple syringe or with a siphon in which the pressure is regulated
by the height of the vessel containing the injection fluid) either
through the carotid, when one wishes to limit the hardening to
the cerebrum and cerebellum, or through the aorta when the
fluid should also extend to the spinal cord.

‘‘It is superfluous to state that when the bichromate and
gelatine is injected it must be warmed so that it will remain
fluid. In this case it is especially important to perform the
operation immediately after the death of the animal, before the
tissues are cold. Only in this way does one secure the finest
and most widespread injection.

‘‘ After the injection the nervous parts are removed from
their cavities, cut into pieces and brought as usual into bichro-
mate where they are carefully treated as dealt with above.

‘“(6) Hardening in bichromate at a constant temperature. The
circumstance, pointed out several times, that the uncertainty
about the time at which the pieces must be brought from the
bichromate into the silver solution depends for the greater part
upon the temperature of the medium leads to the idea that the
best means of avoiding this inconvenience would be the em-
ployment of a constant temperature for the bichromate in
which the pieces lie. For this purpose the warm chambers used
in investigations upon micro-organisms seem best adapted.

‘‘T have used the chamber of Wiesnegg in which I main-
tained a temperature of 20° to 25°. This had good success but
only in the direction of considerably abbreviating the period of
hardening in bichromate so that the reaction could be obtained
much sooner than formerly and in a tolerably constant period
of time. Thus the reaction in the warm chamber appeared
after 8 to 10 days and proceeded to completion up to 15 to 20

116 JOURNAL OF COMPARATIVE NEUROLOGY.

days. This is, perhaps, an advantage in so far as one can with
sureness obtain certain preparations for demonstrations in a tol-
erably brief time. But the advantage is not extended to the
fineness of the result since in all such preparations the reaction
turns out rather coarse. I was not thereby encouraged to ex-
tend experiments in this direction, especially as the abbrevia-
tion of the time can be attained in other simpler ways and as
the pieces in the chamber quickly pass by the period favorable
to the success of the reaction without attaining the kind of
hardening sought—which is a not insignificant disadvantage.

‘‘(c) Hardening in Erlicki’s fuud (bichromate of potassium,
2% g.; copper sulphate, % g.; distilled water, 100 g.). Re-
garding this I confine myself to stating that the copper salt
added to the bichromate did not prevent the reaction and that
the Erlicki’s fluid possessed the same advantages and disadvan-
tages as the preceding method (warm chamber). It accelerates
the hardening so that ina few days (6 to 8 to 10) the black
stain of various elements of the nervous system can be ob-
tained by transferring to silver, but the result cannot be com-
mended for fineness. Moreover the period advantageous for the
reaction is very quickly passed over.

‘« As it appeared to me that the limited and not very fine
form of the reaction might be due in part to the rapid action of
the hardening fluid, I weakened the same by mixing it in grad-
ually increasing quatities with Miiller’s fluid (Erlicki 20% to
50%, Miller 80% to 50%). The results obtained by means of
this variation were decidedly good. After only 5 to 6 to 8 days
immersion in such a fluid I obtained preparations which in re-
gard to fineness of result had a certain worth. It thus appears
to me that this variation can be recommended for the purpose
of quick demonstrations of cell-forms. For the finest details,
especially the relation of the functional processes of the gang-
lion cells and the nerve fibers, I find that the first procedure is
always to be preferred, or also the following :

‘62. Method of the successive actions of a mixture of osmic
acid with bichromate and of the silver nitrate. This procedure
also is only a modification of the original but deserves a place in

SrronG, Review of the Golgt Method. 117

the exposition as a method by itself, partly because the not unim-
portant changes of the results which it yields and the treatment
which it requires are to be ascribed to the newly added re-
agent, partly because the process so modified can remedy some
inconveniences of the original method.

‘«Tt can be applied in two ways, namely :

‘‘(a)_ By laying small pieces of nervous tissue directly in
a mixture of bichromate and osmic acid (2% to 2%% sol. of bi-
chromate, 8 parts; 1% sol. of osmic acic, 2 parts).

‘“‘The black stain is obtained the most quickly with this
procedure. The black staining of a great number of nervous
elements can be obtained by transferring into silver at the second
or third day (see the directions for procedure in the description
of the original method). The reaction extends itself on the im-
mediately following days, then, as usual, diminishes and at the
tenth or twelfth day entirely ceases.

‘‘The treatment of the macro- and microscopical prepara-
tions which are obtained in this way must be considerably modi-
fied. Pieces prepared by this method differ trom those prepared
by the first method inasmuch as when they are kept a long time
for future use, they become diffusely blackened and thereby use-
less. They must be kept in the same silver solution which has serv-
ed for the reaction. Then they are brought into pure alcohol,
which must be changed, where they remain not longer than two
days, sectioned and subjected to the above described treatment
(absolute alcohol with repeated washing, creosote, turpentine,
damar) necessary for their permanent preservation as micro-
scopical preparations.

‘Although this application of the osmium-bichromate
solution is certain and, as far as fineness is concerned, yields
satisfactory results; yet I find that for a systematic study of any
definite portion of the nervous system the following method is
far preferable:

‘““(b) Bringing of fresh pieces into the bichromate solution ;
first transference into an osmium-bichromate solution ; second trans-
ference into the silver solution. It is different with this second
procedure than with the preceding, in which the series of pieces

118 JOURNAL OF COMPARATIVE NEUROLOGY.

of tissue to be examined are useless after a few days. Here the
fresh pieces (with or without injection) are laid in the bichro-
mate solution and remain, so to speak, in the hand of the inves-
tigator. They can either immediately or later be tried i. e.
during a period of from 3 or 4 to 25 or 30 days after the immer-
sion. If one during this whole period transfers at intervals of
2 to 3 or 4 days some pieces into the osmium-bichromate solu-
tion, he thus possesses many secondary series of pieces which
are brought singly (1 or 2 at a time) into the nitrate solution.
These, from the third or fourth to the eighth or tenth day of
their sojourn in the mixture, yield with certainty, when brought
into the silver, preparations with all the consecutive gradations
and combinations described in the original method and also
possessing surprising fineness.

‘“‘After-treatment. Preservation of the pieces in the silver
solution; pure alcohol for 2 or 3 days, till one has time to un-
dertake the examination; repeated washing out of the sec-
tions with absolute alcohol; cresote, turpentine, damar, mount-
ing without cover glass.

‘This is the method which I at present prefer for the
demonstration of the finest details in the structure of the central
nervous system. The particular grounds for this preference are
the following: (1) Certainty of obtaining the reaction in many
gradations, if one makes use of a certain number of pieces.
(2) The considerable length of time during which one can
obtain the reaction—while one can also attain it in a few days.
This renders an accurate investigation much easier. (3) The
pieces are much more conveniently treated. (4) Finally, one
obtains at the same time with the gentle gradation of the results
also a greater fineness of the same, especially regarding the be-
havior of the functional processes of the ganglion cells.

“©3. Method of the consecutive actions of the bichromate
of potassium and of bichloride of mercury. This can likewise
yield valuable results whose value is not diminished because
they in many respects conform to those obtained by the silver
nitrate. Indeed, the particular purposes it can fulfil and_ its
peculiar advantages are in and for themselves so important that

SrroneG, Review of the Golgt Method. 1@ fe)

it must be given a place of its own alongside the silver nitrate
method. The clearness with which the various elements of the
nervous system emerge in this reaction is not less than that
brought about by the silver nitrate. The elements appear,
when viewed under the microscope by transmitted light, com-
pletely black after the action of the sublimate and for micro-
scopal investigation the action is the same as when there is an
actual black stain. But this stain is only an appearance due to
the opacity of the elements upon which, probably owing toa
reducing action, the mercury has precipitated. In reflected
light one notices that the elements appear entirely white, indeed
under stronger magnification they show plainly a metallic luster.

“‘T will remark that the particular advantages of this
method consist first in the fact that the reaction can take place
in large pieces, further that its success is absolutely certain with-
out being necessarily bound by strict rules as to the time of
sojourn in the hardening fluid, and finally in the fact that the
preparations which it yields require no especial precautions for
their preparation, but can be treated in the usual way, like sec-
tions stained with carmine.

‘The mode of application of the sublimate method is only
distinguished from the silver method by some unessential things.
It likewise consists of two essential processes:

‘‘(a) Hardening of the pieces in bichromate.

‘‘(b) Transference of the same into a solution of bichlo-
ride of mercury and sojourn in the latter.

‘¢(a) The hardening in bichromate is done entirely in the
usual way. (See the original method).: I only add that the
reaction does not proceed in an essentially different manner
if consecutively stronger solutions of I, 2, 3% are employed or
if the pieces are immediately laid in Miuller’s fluid. In general
it is expedient for the pieces to be small but this is not abso-
lutely necessary. Good results are also obtained with large
pieces, indeed with whole brains. In the latter case the pre-
serving fluids require a long time to pentetrate by osmosis from
the periphery into the interior and the central portions could
spoil before they experienced the action of the fluid. It is nec-

120 JOURNAL OF COMPARATIVE NEUROLOGY.

essary therefore to make a careful preliminary injection of
bichromate solution so that the reagent is well distributed
throughout the organ.

‘‘A few days (6 to 8 or less) sojourn in the bichromate
solution is sufficient to obtain, by putting the pieces into subli-
mate solution, an extended fine black stain of a greater or less
number of cells (indeed one can obtain an indication of the reac-
tion on the fresh brain which is placed immediately in the subli-
_ mate solution). A more suitable period to obtain fine and
extended results is from 20 to 30 days. A much longer hard-
ening (from 2, 3, 4 months or more) is by no means unfavorable
for the reaction. I remember, among other cases, to have
obtained reactions of wonderful fineness in some whole brains
which were in bichromate solution nearly a whole year.

‘Tt will be perceived that this indefiniteness of the time
constitutes a very advantageous circumstance since thereby
pieces can be employed which would otherwise be useless.

‘«(b) Transference of the pieces into the sublimate solution.
The solution used by me contains %% of bichloride of mer-
cury. I have satisfied myself that the method is equally suc-
cessful when the solution is weaker (144%) or stronger (1%).
The pieces are brought immediately from the bichromate into
this solution.

‘« The reaction throughout the thickness of the piece results
much more slowly than with the silver nitrate. If the pieces
- are suitably hardened, 24 to 48 hours suffices with the latter.
With the sublimate, on the other hand, not less than 8 to Io
days are necessary, in order that the reagent may penetrate
throughout the piece, when the pieces are small and much more
(2 months and upwards) when the pieces are large (whole
brains). The period of action of the bichromate must also be
considered ; the longer this has been, the longer must be the
sojourn in the sublimate, but the more complete and delicate is
the reaction.

‘‘During the sojourn of the pieces in the sublimate solu-
tion, the bichromate with which the tissue is saturated diffuses
out and impairs the purity of the fluid, which assumes a yellow

StrRonG, Review of the Golgi Method. 121

color while the pieces become paler. For this reason the sub-
limate solution must be changed daily, especially at the begin-
ning of the immersion. Later the changes are made only when
the solution becomes yellow.

“‘It may be assumed that the reaction begins when the
pieces are entirely decolorized, i. e. when the tissue is complete-
ly freed from bichromate. If, beginning about this time, sec-
tions are made and examined under the microscope daily, it
will be noticed that the first traces of the reaction begin 3 or 4
days after the immersion and that they can be known bya
number of small black spots scattered here and there. After
4 or § days more one sees the cell-forms gradually become more
complete and numerous and the reaction thenceforward con-
tinues to extend and complete itself. It even appears that
further advantages are gained when the sojourn in the sublimate
solution is extended indefinitely, the sublimate being changed as
often as it becomes yellow through the presence of bichromate.
With brains which have been long exposed to the action of the
bichromate,——and such often yield the most beautiful results,—
the sublimate solution must be changed during several months
before this yellowing ceases.

‘«The above constitutes a further difference from the manner
of action of the silver nitrate, inasmuch as in the latter the
whole action is completed in 24 to 48 hours, after which no
further action is exerted, although the pieces can be kept in
it longer.

‘When the reaction has reached its maximum, the pieces
remain colorless and have the appearance of fresh brain tissue
which has been slightly washed in water.

‘«The pieces may remain in the sublimate solution as long
as one pleases, not only on account of the possibility of a fur-
ther extension of the reaction but also because they thereby
receive a hardening better adapted for making fine sections.

‘« As to the manner in which the reaction extends to the
different elements, I will merely remark that the reaction affects
the ganglion cells in pieces which have reached that degree of
hardening attained in the first month’s immersion in bichromate

122 JOURNAL OF COMPARATIVE NEUROLOGY.

and the reduction only extends itself gradually to the nerve
fibers also. The reaction displays itself to the fullest extent in
the nerve fibers almost exclusively in pieces which have lain
a long time in bichromate and are very strongly hardened.
I recall in this connection the brains which had been kept very
nearly a year in bichromate: they showed an almost universal
very fine stain of the bundles of nerve fibers and of their finest
subdivision.

‘* Treatment and preservation of microscopical preparations.
The only special precaution required by preparations made by
means of the sublimate reaction before they are mounted in
glycerine or balsam is a careful washing in water. Without
this precaution a precipitate in the form of a black powder or
needle-shaped crystals is formed in the sections some days after
mounting and if it does not entirely spoil, yet seriously mars
them. As to the rest, the usual mode of preparation is employ-
ed: mounting in glycerine, damar or Canada balsam after the
necessary dehydration in absolute alcohol and clearing in -creo-
sote or clove oil. No further precaution is necessary.

‘«When I described this method the first time’ I expressed
the conviction that it could be still further perfected so as to
yield finer results than those hitherto attained by me. Practice
has later led me to some modifications which have improved it.
But it has experienced another important development owing to
the perservering experiments of Dr. Mondino who succeeded in
applying the process with remarkable success to nothing Jess
than a whole human brain. I will here add the words them-
selves in which this observer summarizes the advantages which
one can gain from the use of the bichloride of mercury for the
study of the central nervous system.

ICAMILLO GOLGI, Di una nuova reazione apparentemente nera delle cel-
lule nervose cerebrali ottenuta col bichluro di mercurio, Archivio per le Sc.
med,. Vol. III.

STRONG, Review of the Golgt Method. 123

‘The following is Dr. Mondino’s Summary :'

‘“«« A, The sublimate method is the first by means of
which we can obtain the black stain of the nerve cells and their
functional processes in the entire brain and enables us to follow
these latter directly in their course through the brain.

‘«« There is no doubt but that this technique fulfils the re-
quirements of scientific accuracy better and puts us in a better
position to obtain precise knowledge of the so much debated
course of the fibers in the brain than all the methods hitherto
tried. At the most one could only, with the aid of the latter,
see whether numerous functional processes, collected into bun-
dles, proceed in certain directions but with our technique one
can examine them fiber by fiber and follow their anastomoses.

‘««*B. In all other methods we must, in order to obtain
consecutive series of brain sections, bring the individual sections
into vessels with the staining fluid. “As one cannot provide so
many vessels with fluid unless he possesses unusual means, sev-
ral sections must be brought into one vessel and can therefore
only be enumerated by groups and not singly. By the method
here described this result can be attained with great ease. -

“« °C. In the: other methods the sections: must’ be very
thin and are liable to be torn in the various manipulations (from
the microtome into the staining fluid, then to the slide, etc).
As the sections are very thin they must also be much more nu-
merous when a whole brain is sectioned ; hence greater expense,
loss of time and more labor in making the preparations. In our
method the sections need not be thin, they are therefore less
numerous and exposed to fewer risks; whence little danger of
losing sections, slight expense in the preparation and greater
rapidity in the preparation of a whole brain.

‘««D. Finally one must use in all other methods dyes,
commercial and absolute alcohol and clove oil or turpentine,
while we employ a little sublimate and creosote, which are

IMONDINO. Sull’uso del bichloruro di mercurio nello studio degli organi
centrali del sistema nervoso. Communic. fatta alla R. Accad. di Med. di
Torino nella Seduta del 2 Genn., 1885,

124 JoURNAL OF COMPARATIVE NEUROLOGY.

very cheap and inexpensive. In the other methods we must
use cover slips, because the high magnification which they re-
quire—and then one does not see much—would not be applicable
with the thick layers of damar. We do not require this and

thereby escape not only expense but also the difficulty of
avoiding bubbles of air under large coverslips whereby the pre-
paration is often endangered.’

‘‘Tt appears to me, apart from all economy of material,
time and labor, as well as the convenience of cutting pieces in
the microtome so to speak at odd moments without injury to
them from the long contact with water, that this method which
enables us for the first time to follow in sections the course of
nerve fibers through the whole brain shows an advance in the
technique of the study of the central nervous system and takes
precedence over all others.

‘‘As I pass over the application for the macroscopical study
of the brain which Dr. Mondino has also made of this method,
I will here in conclusion again assert that the sublimate method
takes a high place among the microscopical methods for the
study of the nerve centers, alongside of the methods in which
silver nitrate plays the chief role.”

Additional technical notes in Golgi’s article, ‘‘Das diffuse
nervose Netz der Centralorgane des Nervensystems. Seine phy-
siologische Bedeutung ”’ (from the Rendiconti des R. Instituto
Lombardo, Ser. II, Vol. XXIV, Fasc. 8 and 9), pp. 259 and
260 of the German edition of Golgi’s works:

‘‘The method which was most useful to me in the investi-
gations described in the first part of this work, was the staining
of the nervous elements with mercury sublimate, but with a
modification which enhanced its demonstrative value without
changing the fundamental procedure. The latter consists (1)
in the hardening of the pieces in bichromate of potassium,
(2) in the transference from this into a %% to 1% solution of
bichloride of mercury.

‘«Since I have given in another work (Studi sulla fina ana-
tomia degli organi centrali del sistema nervoso, p. 202) a detailed
description of what I call the fundamental part of the method, I

Srrone, Review of the Golgt Method. 125

consider it fitting to add that the best and finest reactions in the
nerve fibers and the interstitial diffuse network was observed
by me in pieces (from the spinal cord of the new-born kitten)
which had lain a long time (in part over two years) in a one per
cent. solution of sublimate after a long preceding sojourn ina
bichromate solution (first, Muller's fluid, then, pure bichromate
to 3%). Since they were pieces which had lain in the labora-
tory in this way ready for examination but had not been used, I
can, naturally, not tell what influence the long sojourn in the
sublimate may have exerted.

‘©The modification introduced by me, to which I must at-
tribute a certain value for the clear demonstration of fine details
and to which I call the attention of the observer, consists simply
in a slight addition, viz., the blackening of the glistening white
stain which the nerve elements receive by means of the mercury
impregnation.

‘‘ As is known, the elements treated with sublimate appear
black in transmitted light on account of the opacity caused by
the reaction but in reflected light they appear white. This dif-
ference may be easily observed by turning off the mirror of the
microscope.

‘«This kind of appearance is satisfactory for observation
with low or medium magnification, where less fine details are
concerned, but it is otherwise with the finer details where
stronger magnification is required. In this case the metallic
luster of the fine parts, e. g. the finest divisions of the nerve
fibers, evidently affects the observation unfavorably by giving
the pictures a certain indistinctness. The black stain which re-
places the white-metallic brings out better the outlines of the
fibers and so increases the demonstrative value of the pre-
paration.

‘‘TInasmuch as the impregnation consists of metallic mer-
cury, the transformation of the metallic white into deep black
can be accomplished, according to the teaching of elementary
chemistry, by means of a number of reagents. There can serve
for this purpose: the sulphite and hyposulphite (particularly
sodium sulphite and hyposulphite in 5% solution), the sulphide

126 JOURNAL OF COMPARATIVE NEUROLOGY.

(of potassium, sodium and ammonium, the first two in 1% to
2%, the third in %% solutions), sulphuretted hydrogen (one
part of the saturated solution and three parts of distilled water).
One can also use with advantage the sulphocyanide (of potas-
sium, sodium and ammonium in 2% solutions).

‘« The solutions of sulphite and hyposulphite, especially the
second, render necessary a careful watching of the preparations
that they are not entirely destroyed through a disappearance of
the metallic impregnation.

‘The sulphide (of potassium and sodium) are easier to
manage but the complete preservation of the preparations is not
entirely certain with them.

‘‘The sulphocyanide acts very well in bringing into view
the smallest parts upon which the metallic impregnation has act-
ed but it does not give a uniform black, only a brownish stain.
Besides this the cells and fibers under the action of this reagent
assume a punctate, almost pulverulent appearance.

‘‘Sulphuretted hydrogen is very disagreeable on account
of its offensive smell (a peculiarity which it has in common with
ammonium sulphide) and it also has a tendency (as has the am-
monium sulphide) to stain those parts containing no subli-
mate brownish, which impairs very greatly the clearness of the

preparation.
‘‘ From all these grounds, and, particularly on account of

its rapidity and certainty of action, on account of the intensity,
uniformity and sharpness of the black stain obtained and on ac-
count of the certain permanency of the preparations, the mix-
ture used by photographers to stain and fix their pictures upon
aristotype paper is to be preferred to all the other substances
given here (naturally for the special purpose of the treatment of
the sublimate preparations).

‘‘From the many formulae of this kind which are found in
books on photographic technique, I have adopted one which I
repeat in a footnote.!

For toning the two following solutions are separately prepared :
(a) Water, 1 liter,
Sodium hyposulphite, 175 g.

StronG, Review of the Golgi Method. 127

‘“«The modification which I have adopted with my subli-
mate method is as follows:

‘«The pieces which have been proven to be successfully
impregnated are imbedded in celloidin in the usual way and
cut with the microtome. The sections are then subjected to
the following treatment :

‘‘(1) Washing in distilled water.

‘©(2) Immersion one or two minutes (they can also re-
main several minutes without injury) in the above fixing and
staining fluid. Several cubic centimeters of the fluid suffice
for many sections. The blackening can be observed with the
naked eye.

‘©(3) Careful washing in distilled water.

‘©(4) If desired, light carmine stain to bring out the cell
bodies and nuclei in the fine interstitial nervous network. Acid
carmine is best adapted for this according to my experience and
I find especially suitable a dilution of this staining fluid with
acetic acid and alcohol (equal parts). The fluid into which the
sections are brought must have a deep red color.

‘“(5) Repeated washing in water and then successive
transference into alcohol and clove oil and finally mounting in
Canada balsam or damar in the usual way.

‘« Preparations treated in this way possess, besides the
above mentioned advantages, the additional one that the fine
powdery precipitate does not after a while appear. This pre-
cipitate almost always, if there have not been previous repeated
and long continued washings, at last spoils the preparations
prepared according to the original method.”’

[ro BE CONTINUED. |

Alum, 20 g.
Ammonium sulphocyanide, Io g.
Sodium chloride, 40 g.
This mixture stands quiet for 8 days and is then filtered.
(b) Water, roo g.
Gold chloride, 1 g.
To prepare the bath one mixes
of solution (a), 60 ccm.
6G ce (b), 7 ccm.
old, combined bath, 40 ccm.
For economy and convenience I use the fluid which has also served for ton-
ing, thus for this purpose almost useless.

THE DORSAL SACK, THE AULIX AND THE DEER
CEPHALIC (RVUEXURE:

B. G. WILDER.
Abstract.

In many of the lower vertebrates there is a pouch-like
evagination of the diatela (membranous roof of the diacele, or
‘third ventricle’’) between the epiphysis and the paraphysis.
In Ceratodus and in Polyodon it is anteverted and very large.
In the green turtle it projects dorsad. Its mammalian repre-
sentative is crowded caudad by the cerebrum and rests upon the
retroverted epiphysis. It is commonly ignored in figures and
descriptions, but was shown by Reichert. The speaker, with-
out recognizing its homology, figured it in the Mew York Medt-
cal Journal, 1885, p. 320. It is large in the sheep and long in
the cow and horse. The diaplexuses are continued into it.

Aulx is the mononym proposed by the speaker in 1882
for the ‘Sulcus Monroi” of Reichert—a sigmoid groove on
the mesal surface of the thalamus just ventrad of the medicom-
missure and connecting the orifice of the mesocele with the
porta (foramen of Monro) at either side. His and C. S. Minot
regard it as the diencephalic representative of the ‘‘ salcus inter-
zonalis,” the primary furrow between the dorsal and ventral
zones of the nervous axis. But recent observations in the
neurologic laboratory at Cornell upon embryo kittens render this
interpretation somewhat doubtful, and the matter is under inves-
tigation.

In 1889, in the ‘‘ Reference Hand-Book of the Medical
Sciences”’ the speaker called attention to the sharp angle be-
tween the prosencephalic and the diencephalic portions of the
brain cavities. A recent review of the brains of all vertebrate

'Read before the American Neurological Association, June 4, 1896.

Wiper, Parietal and Paroccipital Fissures. 129

classes warrants the generalization that a marked diencephalic
flexure occurs in all Reptiles, Birds and Mammals, while in
Amphibians and ‘‘fishes’”’ it is absent or insignificant.

tit ECTAL RELATIONS OF Tie RIGHT AND- EERE
PARIETAL AND) PAROCEIPITAL HISSURES?

B. G. WILDER.
Abstract.

The parietal and paroccipital fissures may be either com-
pletely separated by an isthmus, or apparently continuous.
When so continuous ectally there may still be an ental and con-
cealed vadum or shallow. Disregarding the vadum on the pres-
ent occasion, the ectal relations of the two fissures may be des-
ignated as either contenwty or separation. That continuity oc-
curs more frequently on the left side has been noted by Ecker,
Cunningham and the writer. Hitherto, however, statistics have
included unmated hemicerebrums as well as mates from the
same individuals. The following statement is based upon the
cerebrums of 58 adults of both sexes and various nationalities
and characters. The speaker has examined 48; the other 10
have been accurately recorded by Bischoff, Dana, Jensen and
Mills.

The four possible combinations of right and left continuity
and separation occurred as follows:

I. Left continuity and right separation in 27; 46.5%.

II. Right and left continuity in 22; 38 %.

III. Right and left separation in 8; 13.8 %.
IV. Left separation and right continuity in 1; 1.7%.

1Read before the American Neurological Association, June 3, 1896.

130 JOURNAL OF COMPARATIVE NEUROLOGY.

When 5 groups of persons are recognized the combina-

tions are as follows:
~ A. In 8 moral and educated persons, combination I,
62753 Th 25 Tit ras.

B. In 23 ignorant or unknown, I, 56.5; II, 34.8; II, 8.7.

Cin 2oinsane) 1,40. ieo5 il 20) al Vege

De Mniaomurderers, Teo; Me 7s el be

Bo ines mearoes, les emis oys

So far as these 58 individuals are concerned, the most com-
mon combination, vzz., left continuity and right separation, is
decidedly the rule with the moral and educated, less frequent
with the ignorant and unknown, the insane and negroes, and
does not occur at all in the murderers. The only instance of
the reverse combination (left separation and right continuity) is
an insane Swiss woman. The only two known to be left-handed
presented the more frequent combination I.

These statistics suggest many special queries and problems,
some of which were briefly indicated. But the speaker wished
this to be regarded as a preliminary communication and asked
the cooperation of other members in the effort to obtain satis-
factory records of larger numbers, particularly of brains of well-
born, moral and educated persons. For this purpose a blank
form was outlined and will be sent upon application.

EDITORIAL.

NEURONYMIC PROGRESS IN AMERICA.

The American Neurological Association, at its recent ses-
sion in Philadelphia, took a step at once sure and decided toward
the simplification and unification of neurologic nomenclature.
The Committee on Neuronymy (Drs. H. H. Donaldson, L.
GrGray,-Cy Ke Mills iC. Seguin, i. Ca-spitzka sandy Bs iG:
Wilder, chairman) presented a report which was adopted
unanimously by the Association, June 6. To give this impor-
tant measure as wide a circulation as possible we publish the
report of the committee as furnished us by its chairman.

The first five sections are substantially identical with re-
ports that were adopted unanimously by the Association of
American Anatomists in 1889 and by the American Association
for the Advancement of Science in 1890 and 1892. The re-
commendations are as follows:

1. That the adjectives borsAL and VENTRAL be employed
in place of posterior and axterior as commonly used in human
anatomy, and in place of upper and dower as sometimes used in
comparative anatomy.

2. That the cornua of the spinal cord, and the spinal
nerve-roots, be designated as DORSAL and VENTRAL rather than
as postertor and anterior.

3. That the costiferous vertebre be called THORACIC rather
than dorsal.

4. That, other things being equal, Mononyms (single-word
terms) be preferred to polyonyms (terms consisting of two or
more words).

5. That the Azppocampus minor be called cALCAR; the
hippocampus major, HIPPOCAMPUS; the fous Varoliz, pons; the
msula Retlit, INSULA; pra mater and dura mater, respectively PIA
and DURA.

132 JoURNAL OF COMPARATIVE NEUROLOGY.

6. That the following be employed rather than their vari-
ous synonyms: HYPOPHYSIS, EPIPHYSIS (for coxarimm and cor-
pus pineale), CHIASMA, OBLONGATA, LEMNISCUS, MONTICULUS, TEG-
MENTUM, PULVINAR, FALX, TENTORIUM, THALAMUS, CALLOSUM,
STRIATUM, DENTATUM, MESENCEPHALON, PALLIUM, OLIVA, CLAVA,
OPERCULUM, FISSURA CENTRALIS (for f. Rolando, etc.), F. CAL-
CARINA, F. COLLATERALIS, F. HIPPOCAMPI, CUNEUS, PRAECUNEUS,
CLAUSTRUM, FORNIX, INFUNDIBULUM, VERMIS.

It will be noted that at least twenty (about half) of the
names above recommended coincide with those adopted by the
European committee in 1895, and that with some others, e. g.
CALLOSUM, DURA and CALCAR, the difference is due merely to
the elimination of superfluous words.

The next number of the JouRNAL OF COMPARATIVE NEv-
ROLOGY will contain an extended commentary upon the Report
by the chairman of the committee.

Journal of Comparative Neurology. Vol. VI. PLATE IX,

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Journal of Comparative Neurology. Vol. VI. PLATE XII

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Journal of Comparative Neurology. Vol. V1 PLATE XiIll.

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THE BRAIN OF THE BEE

A PRELIMINARY CONTRIBUTION TO THE MORPHOLOGY OF THE
NERVOUS SYSTEM OF THE ARTHROPODA.

By F. C. Kenyon, Ph.D.,
Fellow in Biology, Clark University, Worcester, Mass.

CONTENTS.

Introduction.

MATERIALS.
METHODs,

General description.

External appearance.
CEREBRAL NERVES,
GENERAL INTERNAL STRUCTURE.
TYPES OF NERVE CELLS.
CONNECTION BETWEEN NERVE FIBERS.
TRACHEA,

Special description, the Proto-cerebron.

THE MUSHROOM BODIES,
The calyx-cup.
The stalks of the mushroom bodies,
The roots of the mushroom bodies.
MINUTE STRUCTURE OF THE MUSHROOM BODIES.
fibers ending in the calyx.
Fibers ending in the stalks and roots.
THE FUNCTION OF THE NERVE CELLS OF THE MUSHROOM BODIES,
THE CENTRAL BODY.
THE TUBERCLES OF THE CENTRAL BODY.
THE FIBRILLAR ARCH.
THE ASSOCIATION FIBERS OF THE PROTO-CEREBRON,

The Deuto-cerebron.

THE ANTENNAL LOBE,
THE ROOT OF THE ANTENNO-SENSORY NERVE.
THE ROOT OF THE ANTENNO-MOTOR NERVES,

134 JOURNAL OF COMPARATIVE NEUROLOGY.

The dorso-cerebral fiber tracts.
THE CONNECTIONS WITH THE OPTIC LOBES.
The anterior optic tract.
The postero-superior optic tract.
The antero-supertor optic tract.
The antero-posterior optic tract.
The posterior optic tracts.
THE DORSO-CEREBRAL COMMISSURES.
The superior dorso-cerebral commissure.
The anterior commissure.
The optic commussures.
The inferior dorso-cerebral commissures.
THE ANTENNO-CEREBRAL TRACTS.
The inner antenno-cerebral tract.
The middlé antenno-cerebral tract.
The outer antenno-cerebral tract.
THE DORSO-VENTRAL TRACT.
The ocellar nerves.

FIBERS FROM THE BRAIN TO THE OCELLAR GANGLIA.
The commissural and ventro-cerebral region.

The cell groups.

THE CELLS OF THE DORSO-CEREBRON.
THE CELLS OF THE VENTRO-CEREBRON,

Conclusion.
Bibliography.
introduction.

Since Viallanes’ (gs) monograph on the brain of the grass-
hopper (Oedopoda and Caloptenus) and the smaller but as excel-
lent work of Cuccati on the organization of the brain of So-
momya appeared nothing has been added to our knowledge of
the structure of the hexapod brain. In fact no one seems to
have worked at the subject. Such being the case, my endeavor
by an application of one of the more recent histo-neurological
methods to bring this subject into line with what is now known
relative to the stucture of the central nervous system of several
other zxvertebrates and more especially of the vertebrates will
doubtless be appreciated. Here, as elsewhere, an application
of the chief of the two recent methods, namely that of Golgi,
brings to light facts before known only from inference, and also
often materially alters conceptions based wholly upon the older

Kenyon, Zhe Brain of the Bee. 135

methods of staining. A detailed history of the matter in hand
is therefore needed, but since it would add too much to the
length of the present paper, the pretentions of which as indi-
cated in the title are very limited, little more than a reference
here and there will be given. This course is doubtless excusa-
ble since Retzius (99) has already given a summary to which the
reader may be referred. Three papers that have appeared since
the publication of this author’s work may, however, be noted.

The first of these is the paper by Saint-Remy (99) on the
brain of tracheate arthropoda. In this the author describes the
brains studied histologically of myriopods, chilopods, arach-
nids and Perzpatus; but although the work is comprehensive
and fills a void in our knowledge of the arthropod nervous sys-
tem, it is far from treating the subject with sufficient depth, a
deficiency mostly due to the method of staining employed.
The nerve cells, or cell bodies, following Dietl, he divides into
two groups, one composed of large cells well supplied with ex-
tra-nuclear protoplasm and with relatively small nuclei having
few chromatin elements, the other of small cells having little or
no extra-nuclear protoplasm and relatively large nuclei richly
supplied with chromatin elements and restricted to certain cere-
bral areas. To the latter he applies the term chromatin cells
in preference to the ganglionary nuclei of Dietl and others.

Two small nerves that he describes for the myriopods may
be passed by with the remark that one, namely the nerve of
Tomosvary appears to have no homologue in the hexapods un-
less it be the small nerve mentioned by Newton ( 79) as arising
from the front of the brain of the cockroach and terminating in
a small organ near the base of the antenna. The other, or
tegumentary, nerve may be the homologue of the tegumentary
nerve described by Viallanes (gg) for the grasshoppers and con-
sequently, as will be shown in subsequent pages, the homo-
logue of the salivary nerve that I have traced out in the bee.

The most interesting discovery recorded in the paper is
that of structures found in the brain of Scutzgrva that he de-
scribes as mushroom bodies. The term he bases upon their
form and not upon an idea of their being the homologues of the

136 JOURNAL OF COMPARATIVE NEUROLOGY.

organs of the same name found in the hexapods. But from
the fact that their cells are of the chromatic cell type and simi-
larly situated andalso from the fact that he seems able to recognize
nearly all the parts generally described in the organs in the hex-
apods it may here be suggested that they may possibly be the
homologues of these latter organs. There is needed, however,
a more minute and painstaking study than St. Remy has given
the structures before one should come to a definite conclusion as
to their homologies.

The second of the three papers is that by Viallanes (93)
on ‘‘The neural centers and sensory organs of articulates ’’ and
is mainly of interest here in showing this author’s conception of
the minute structure of the nervous system. In his earlier pa-
pers he did not touch upon the matter, but in his last paper
one finds him following St. Remy’s grouping of the cells and
adding a few ideas upon the finer structure of the fibrillar sub-
stance. These ideas were doubtless founded more upon the
general results obtained with the methylen blue and the Golgi
methods, which by this time had become very generally known,
than upon any observations of his own made by the aid of his
methods of staining.

He describes and figures diagrammatically three kinds of
fibers. One of these, of large size, originates from large
cells and passes outside of the central nervous system after first
giving off in the latter a few short and fine branches. These
he calls motor fibers. Another kind, of much smaller size, enter
from cells outside the central system and branching more or less
profusely connect with the small branchlets of the first, forming
thus the terminations and connections of sensory fibers.

The third kind are short, small fibers originating from
the chromatin cells and, branching profusely, connect with
the fine branchlets of the other two kinds of fibers. As will
be seen in subsequent pages, this general idea is supported by
facts, though, as indicated above, it was with Viallanes almost
purely hypothetical.

The last of the three papers is one by Binet (94). This
author so far as the structure of the dorso-cerebron is concerned

Kenyon, Zhe Brain of the Bee. 137

seems to follow Viallanes without a question, and deals almost
wholly with the ventral system, which he treats anatomically
and physiologically. He seems to have added a few new facts
to our knowledge of the subject treated, although he leaves
very much still to be done. The points at which he seems to
have erred or where his treatment is deficient will be noted,
when they are closely related to the matter in hand, in subse-
quent pages. Here it may be noted that he seems to have ob-
tained the beginning of a correct idea of the constitution of the
arthropod nervous system based upon the work of Retzius and
others employing similar methods; but, failing completely in
his use of the Cajal-Golgi method and obtaining but litttle better
results with methylen blue, he concludes that, since in any one
preparation neither of these methods brings out the whole structure
they are not to be depended upon, and then passes on to a de-
pendence upona modification of the old method of Weigert
and becomes lost in the mass of detail that he so much desired
to obtain.

The results of other writers will be noted in connection
with the descriptions of the structures with which their works
deal.

MATERIAL.

The material used has been almost exclusively the common
honey bee (Afzs mellifica), which was at hand in abundance,
for which I owe many thanks to Dr. C. F. Hodge. Possibly a
thousand or more brains were treated by several of the bichro-
mate of silver methods, and of this number scarcely more than
fifteen or twenty per cent. were found successfully impregnated.

METHODS.

Aside from impregnation with bichromate of silver, the
methods that I have employed are various, and among these the
one that has given the best results, brought details to light most
beautifully, has been one using sulphate of copper and haema-
toxylin with brains hardened in from 10 to 20% formol for
twenty four hours or longer. Such preparations show the axis-
cylinders as purplish-brown fibers within their surrounding

138 JOURNAL OF COMPARATIVE NEUROLOGY.

slightly bluish sheaths, the nuclei of the latter and of trachee,
the tracts of nerve fibers and some of the association fibers,
clearly marked off from the surrounding ground work of fine
branchlets forming the Punktsubstanz of the older German
writers and the medullary substance of Viallanes. The struc-
ture of the cell bodies and their nuclei is also well brought out.

In some cases the freshly excised brains were dropped into
10 to 20% formol, in others they were placed in the following
mixture, which gave just about as good results :

10% Potassium bichromate, 40 parts.
5% Sulphate of copper, —_40 parts.
Formol, ° : 20 parts.

This might be improved by leaving out the bichromate,
which is rather unnecessary since the formol likewise has the
property of rendering the components of animal tissues insolu-
ble in water and alcohol.

Brains hardened in this mixture were washed for from a
little while to some hours in tap water, then for from a few to
twenty four hours in 70% alcohol, after which they were de-
hydrated, imbedded in paraffin, sectioned and stained on the
slide in the hamatoxylin.

In the other cases the sections of the formol-hardened
brains were treated with the sulphate of copper (5%). Ina
solution of this they were left for from a few to twenty four
hours or in a warmed solution for from 20 to 30 minutes. They
were then washed off in tap water and stained.

The hematoxylin mixture that gives the best results is
one containing phosphomolybdic acid, though the plain alcohol-
water hematoxylin used in the method of Weigert and its
modifications gave good results for certain details in the roots
of the mushroom bodies. The former mixture is that suggested
by Mallory and is composed as follows :

10% Phosphomolybdic acid WC.c.
Hematoxylin crystals I grm.
Chloral hydrate : 6 to 10 grm.

Water 4 : : 100 C.¢,

Kenyon, Zhe Brain of the Bee. 139

Enough of this was added to a dish of water to give the
latter a black appearance, or it was diluted about I to 5. From
a quarter of an hour to an hour is required for staining. The
sections hardened in the potassium bichromate mixture require
a longer time than the others.

After staining, the sections were washed off with 70%
alcohol and dehydrated or, if too deeply stained, left in the 70%
alcohol for some time. With the dilute solution, however, there
is not much danger of overstaining, if the process is watched.

For impregnation with bichromate of silver the rapid
method of Cajal was at first employed, but only later to be set
aside when it was discovered that one in which the osmic acid is
replaced by formol gives a much more transparent background
for the darkened fibers and cells, thus allowing much thicker
sections to be cut, while at the same time retaining the
rapidity that has made the osmic acid mixture so excel-
lent. At first the osmic acid was replaced by the same
amount (one-fifth) of pure formol, later Strong’s suggestion
of equal parts of 10% potassium bichromate and _ formol
was followed. This was then modified to 5% bichromate
and a smaller amount of formol as follows :

5% bichromate, 8o cc.
Formol, 20 cc.

This gave impregnations as good as the stronger and a lit-
tle better than the weaker combination while at the same time
lessening the formation of a black precipitate that. is always
found in formol-bichromate mixtures after they have stood some
hours. This precipitate was avoided as much as possible by
changing to fresh fluid every twenty-four hours. Impregnations
may be obtained in brains left unchanged in the mixture until
ready for the silver solution. The precipitate must however weak-
en both the formol and the bichromate and hence operate disad-
vantageously. I think my failures were more numerous with
brains left in the unchanged fluid, (though no experiments were
undertaken to settle the matter definitely,) and hence I am not
inclined to agree wholly with Kopsch (96) when he asserts that
the precipitate makes no material difference.

140 JOURNAL OF COMPARATIVE NEUROLOGY.

Like this writer, I also found that twenty-four hours in the
formol-bichromate is sufficient for hardening and that tissues
may then be transferred to pure bichromate. He employed a
344% solution, however, while I, since it seemed to act more
quickly, used a 5% solution.

From three to four or five days immersion in formol-bi-
chromate are necessary for obtaining impregnations of nerve
fibers, and almost three for the cells, while the tracheee may
be incrusted almost to the exclusion of nerve fibers after one
or two days.

The more or less inevitable precipitate and crystals were of
course met with, but on the whole my preparations were com-
paratively free from them. In fact, judging from the printed
experiences of others, I seem to have been more favored than
is usual. Only a few cases occurred out of the hundreds of
brains sectioned where the precipitate at all resembled the fine
branching of the nerve fibers, and in these there was no ground for
a deception of the practiced eye, for the angular contours of the
precipitate readily distinguished it from the rounded ones of the
fibers.

The precipitate gave the greatest annoyance in the layer of
cell-bodies. This is so thin on the more exposed parts of the
brain that it was usually completely obscured when the brains
were brought into direct contact with the fluids. Attempts were
made to obviate this difficulty. Formic acid was tried and dis-
carded, as was also Berkeley’s (95) suggestion of adding a few
drops of phosphomolybdic acid to the silver solution just before
using. The latter can, in fact, do nothing more than weaken
the solution of silver nitrate, and one may therefore as well take
a weaker solution to begin with. When this is done and the
tissue, after first quickly washing off the bichromate with water,
is carefully rinsed in the weak solution, or one that has been
previously used, before it is allowed to stand, one will be much
less troubled with the incrustation.

This method did not prove as good, however, as one in
which the brain was left zz sztw in the head, enough only of the
front, top, or side of which was cut away to allow the fluids to

Kenyon, Zhe Brain of the Bee. I4!I

enter. In such cases the part most exposed would be incrust-
ed, while that opposite would be entirely free. Other methods
were thought of and tried. That of wrapping a brain in filter
paper was considered too rough a treatment ; covering a brain
with celloidin failed. Had the one suggested by Retzius (9 4),
namely, of dipping a brain in warm gelatine, been thought of or
known in time, it would doubtless have given excellent results.

The nitrate of silver was employed in strengths ranging
from %% to 2%. The stronger solutions, though giving
stronger impregnations, less evidence of beading, or fuller fibers,
have the disadvantage of being more inclined than the weaker
solutions to form artifacts. A solution of 1% strength was
finally adopted for leaving the specimens in over night or until
I was ready to section them.

Generally only one or two immersions in the fluids was
given the specimens, since it was desirable to have only a few
fibers impregnated so that very thick sections could be cut and
thus give the entire trajectory or as much as possible of a fiber
unobscured by other details.

The impregnated brains were transferred to absolute alco-
hol and then to celloidin. Where they were entirely free from
the head or from chitinous particles that would tend to prevent
them from becoming fairly saturated or surrounded with the
celloidin, sections wese cut within two hours from the removal
from the silver solution. But where they were surrounded by
the chitinous cephalic capsule from six to twenty-four hours
were found necessary to form a celloidin block of a consistency
sufficient to prevent tearing and breaking of the sections.

Sections were cut all the way from twenty to two hundred
and ten microns thick, thus, in the thickest, making only three
or four frontal sections to a brain.

General Description.

External appearance.

Under the general term ‘‘brain”’ I here understand the
whole of the neural mass included within the head, excepting
only the two small ganglia generally known as the stomatogastric

142 JOURNAL OF COMPARATIVE NEUROLOGY.

ganglia. The optic lobes and the subcesophageal ganglion are
part of it. There is no real ground for leaving the latter por-
tion out as is generally done under the term subcesophageal.
Even when it is widely separated from the larger mass and is to
be found crowded back into the pro-thorax, there is abundant
reason, as shown by the physiological experiments of Binet
(94) and others, for retaining this portion under the general
term brain. Hence in subsequent pages it will be referred to
as the ventro-cerebron in contrast to the super-intestinal portion
or dorso-cerebron.

The optic lobes will be omiited from this paper for consid-
eration in a later one.

The bee’s brain thus limited is, roughly speaking, when
viewed from the front, a quadrilateral structure, with rounded
angles. Setting aside the ventro-cerebron, which projects back-
ward, it is considerably compressed antero-posteriorly (Pl. XX),
and abuts closely against the middle upper portion of the pos-
terior walls of the head, leaving a very considerable space in
front filled with tracheal air-sacs and the whitish, often yellow-
ish or orange racemose bunches of the salivary glands. These
latter organs also fill in the smaller spaces behind the brain and
are closely applied to it. On the dorsal side are three small
protuberances (Pl. XVII, XX) with black tops, or the so-called
ganglia of the ocelli. Below in the lower third the brain is
pierced by a large oval opening, the cesophageal foramen, with
its largest axis vertical. Near the roof of this is the longitu-
dinal median nerve of the stomatogastric system. On either side
and below the foramen are the rather conspicuous antennal
lobes forming the greater portion of what has been described as
the deuto-cerebron. The ventro-cerebron, as already mentioned,
projects considerably backwards, but it is so closely united with
the dorso-cerebron by extremely thick and short cesophageal
commissures that it is very readily recognized as part of the
brain. So compact is this deuto-trito-cerebral portion of the
brain that were it not for the fact that the labral nerves are rec-
ognized as arising from it, indications of the trito-cerebral lobe

Kenyon, Zhe Brain of the Lee. 143

would be recognizable only in sections. Even in these its boun-
daries are indefinable.

THE CEREBRAL NERVES,

From the lower side of the antennal lobe there is given off
the large antennal nerve, which passes forward and _ slightly
downward to the-entrance of the antenne. From the lower
surface behind the origin of the large nerve there originates
a small one that may be readily traced in sections to the anten-
nal muscles within the head. This, which I will denominate
the antenno-motor internus, in contradistinction to the other, or az-
tenno-motor externus, was first discovered and traced to its termi-
nation in the muscles by Newton (79) in his study of the brain
of the cockroach. It is described by Viallanes (7) in his
paper on the brain of the wasp as the ‘‘nerf antennaire acces-
soire’’ and was correctly identified by him with the nerve de-
scribed by Newton, although he was unable to trace it to its
termination in the muscles. Doubtless it may be found as a
separate nerve in all tracheate arthropods. One occupying the
same position I have recognized in Scalopendrella tmmaculata
and traced into muscles that I supposed to belong to the an-
tenne.

Behind this internal antenno-motor nerve and immediately
behind the base of the antennal lobe there is a somewhat larger
nerve that I have traced towards the mouth-parts of the bee
and from its position take to be the labral nerve. This arises
from the trito-cerebron and may be seen in fragment in the pho-
tograph (fig. 2, Pl. XIV), which is of a section slightly too far
forward to show the lobe and the entering nerve root.

From the lower side of the ventro-cerebron (PI. XX) there
arise not far apart from each other three pairs of large nerves
that like the one just described may be readily traced to the
mouth parts. Since in most of my preparations these parts
were cut away to allow a free access of the fixing fluids to the
brain or to free the object as much as possible from chitinous
parts to avoid tearing during the process of sectioning, I have
not yet traced the nerves to their endings. From their posi-

144 JOURNAL OF COMPARATIVE NEUROLOGY.

tion, however, I infer them to-be the mandibular, maxillary,
and labial nerves. From the posterior lower surface of the
ventro-cerebron there arises a small seventh pair of nerves di-
rected backwards and downward toward the region just below
the foramen magnum. Just how they terminate or what their
function may be I have not thus far been able to determine.
They were seen by Viallanes (7) in the wasp, but were left as
now still to be traced.

In his monograph on the brain of the Orthoptera, Viallanes
(8) described under the name of ‘‘nerfes tegumentaires”’ a
pair of nerves emerging from the surface of the brain and pass-
ing on to the roof of the head. These appear to be nothing
more nor less than a pair of nerves that he found in the wasp
the year before and described as nerves of unknown termina-
tions.

This eighth pair of nerves is readily seen and traced in the
bee and one may be recognized in section in the lower photo-
graph in plate XVI. Both in bichromate of silver and in hema-
toxylin preparations I have been able to trace out its entire
course and to show that Viallanes’ denomination of tegument-
ary nerve is entirely a misnomer. It arises from the side of the
ventro-cerebron where its root enters the latter, passes in, some-
what downwards and backwards, towards the median line of the
latter, makes a turn backwards and becomes lost in the general
mass of fibrillar substance. The nerve (Pl. XVII) closely adher-
ing to the posterior surface of the brain and beneath the gen-
eral envelope of the latter passes outwards and upwards until it
reaches the upper portion of the posterior surface of the inner
or third optic fibrillar mass or ganglion, where it branches. One
branch continues almost perpendicularly upwards, passes out of
the brain envelope and branches among the lobes of the saliv-
ary glands. In bichromate of silver preparations the branches
may be followed into the lobes, but I have not yet seen the
finer terminations. The other large branch continues outward
along the supero-posterior surface of the optic lobe, branching
and leaving the ‘envelope from time to time, and may be fol-
lowed to the basement membrane of the retina where it finally

Kenyon, The brain of the Bee. 145

emerges to pass into the glandular lobes situated in proximity
to that structure. The nerve, then, instead of having anything
to do with the integument, is the nerve to the salivary glands,
and is doubtless made up entirely of efferent fibres.

The small pair of nerves described by Newton (79) as
arising from the anterior surface of the brain in /atta and go-
ing to the small white spot near the base of each antenna,
are not, so far as I have been able to discover, represented in
the bee.

THE GENERAL INTERNAL STRUCTURE.

Internally the brain is composed of a mass of very fine
fibrils scarcely recognizable as such in ordinary preparations,
which is very well called fibrillar substance. The upper portions
of the anterior surface of this below the mushroom bodies to
be described later and the corresponding part of the posterior
portion of each of the two lateral lobes are directly covered by
the membrane forming the perineurium. But in the region of
the mushroom bodies, laterally, in the posterior median furrow,
and below, about the greater part of the antennal lobes, fill-
ing the space between these and the proto-cerebron, and the
lower and lateral surface of the ventro-cerebron (the upper sur-
face of the latter is bare) it is covered by heaps of cells which
spread out into layers of only one or two cells deep. Processes
from many of these cells are gathered into large bundles which,
penetrating the fibrillar substance, give it~—both the brain and
the ventral system as seen in sections—a lobular appearance that
has been the subject of no inconsiderable amount of painstak-
ing and lengthy and as tedious description, notably by Vial-
lanes, and later by Binet (94) in his paper on the sub-intestinal
nervous system of insects. The fibers thus entering become
lost in the fibrillar substance by repeated branching or continue
first to more distant parts, thus forming connecting tracts. This
relation of the fibrillar substance and the fibers may be readily
seen in the accompanying photographs, and in most prepara-
tions by ordinary staining methods. The assistance of the
method of impregnation with bichromate of silver or that of

146 JOURNAL OF COMPARATIVE NEUROLOGY.

intra-vitam staining with methylen blue is necessary to determine
the relations of cells, fibers and fibrillar substance completely.

THE TYPES (OF NERVE (CELES:

By the assistance of the bichromate of silver method we
may imagine a cell with a nerve fiber dividing at some distance
from the cell body into two branches that form with ita Tora Y
as probably the most typical of the nerve cells of the bee, or prob-
ably of arthropods in general. The assertion does not hold
‘good completely, for there are cells in the optic lobes and even
in the central part of the brain in which all the branches given
off appear as very small branches of large fibers.

To classify for convenience of description the various mod-
ifications met with in the brain one may divide them into :

1. Afferent or sensory fibers in which the cell body is situ-
ated somewhere in the neighborhood of the external (to the
brain) organ of sense and sends its neurite into the brain and
its dendrite into the sense organ. Such cells may be called bipolar,
and in them, asin all other nerve cells, the only criterion of
the difference between dendrite and neurite is in the direction
of the passage of the neural impulse with reference to the cell
body, or to the trunk of the fiber leading to the cell body.
Such fibers do not penetrate far into the brain, where they may
terminate in a mass of fine branchlets as in the case of the fibers
from the antenne. In other fibers the terminal branching is
more or less loose or not massed together, as in the case of
whatever sensory fibers there are entering through the labral,
mandibular, maxillary and labial nerves or from the ventral cord.

In the accompanying diagrams this class of fibers and all
others bearing sensory stimuli into the portion of the brain
here considered, as from the optic lobes and the ventral cord,
are colored blue.

2. Connecting fibers in which the cell body is situated to
one side of the track of the passing stimulus—assuming that it
does not necessarily go to the cell body—and in which the
dichotomous T- or Y-shaped branching is most easily recogniz-
able. The peripheral of the two branches connects with the

Kenyon, Zhe Brain of the Bee. 147

terminations of the sensory fibers of the first class and, since it
bears the transferred impulse inward, may be called the den-
drite. Usually it is shorter than the other branch that, with
others of its kind, passes as a tract of fibers through the fibrillar
substance to the mushroom bodies, in which it breaks up
into a bushy or arborescent mass of branches, or to other parts
of the brain, where the branching is of a more open kind.

The fibers connecting the sensory fibers of the antennal
lobes with the mushroom bodies are most typical of this class.
Others that must be classed along with them enter from the
optic lobes and along with them are represented in violet in the
diagrams. Others found connecting the central body, later to
be described, are doubtless to be classed here, since this body
seems to bein connection with the fibers of the ocelli; but
owing to the unsatisfactory condition of my present understand-
ing of this body have been left in black. The mode of branch-
ing at the ends! of the dendrite is represented in fig. 15, PI.
XXI, while the branching terminals in the mushroom bodies
are shown in figs. 17, 18, 21, of the same plate. Most of these
fibers appear to be provided with a nucleated sheath.

The representation of fibers found in the central body in
figs. 32, 37, Pl. XXII, by comparison with figs. 17 and 21 of the
preceding plate, which beyond a doubt represent the receptive
terminations, would seem to indicate that the former are den-
dritic. Fig. 18, Pl. XXI, shows the terminations of the neurite-
branches in the mushroom bodies as seen under a magnifica-
tion of 586 diameters.

3. The cells of the mushroom bodies. These fall under the
head of Y-shaped cells and consequently follow the class just
described, but will be left for consideration along with the
bodies which they largely compose. They are represented
in red.

4. Efferent fibers which originate from cell bodies situated
within the brain and bear efferent stimuli to muscles, glands or
to cells outside of the brain are represented in the diagrams
in brown. The cells of this order seem to depart widely from
the simple T-shaped general type as is shown in fig. 36, Pl.

148 JoURNAL OF COMPARATIVE NEUROLOGY.

XXII, which represents the best specimen of motor cell that
my preparations offered. That it is motor in nature is assumed
from its general appearance, resembling to a certain extent the
motor fibers described and figured by Bethe (95), and the fact
that it is cut off near the cut end of a large fiber not figured
that passes into the antenno-motor nerve and with which it ap-
pears to have been continuous, but on account of a slight
bend outside the plane of the razor was cut in two. This ap-
peared in a nearly sagittal section. In a thick section cut in the
frontal plane, or nearly transversely to the main axis of the
animal’s body, fibers were seen, such as one represented in
Plates XVII and XX, sending a process into a tract of fibers
that appeared to pass down behind the antennal lobe, apparently
into the root of the antennal nerve, which were therefore thought
to be motor fibers. Combining these two with what was seen
of fibers in other sections in about the same locality as the
motor cell mentioned it would appear that the large motor cells
send a process into the fibrillar substance, which almost imme-
diately gives off small branches that may end at a considerable
distance from their point of origin. The process becomes very
much enlarged for a considerable extent of its course and may
even send off branches of considerable size before passing on
into the root of a nerve as a small fiber.

5. TDhe commissural fibers, which are doubtless of the gen-
eral T-shaped form, though I have not been able to find their
cells of origin. They pass from one side of the brain to the
other and may be represented by the fibers composing the
superior commissure. The fibers composing the so-called com-
missure of the optic lobes may possibly also be classed here.
Other fibers there are in plenty than those gathered into tracts
passing between the two halves of the brain, but they are better
classed with the next group.

6. Association fibers seemingly serving the purpose of con-
necting the elements already described with one another. These
are mostly large profusely and irregularly branching forms
some of which are shown in plate XXII. In some“cases I have
been able to make out the cells of these, in others I have not.

Kenyon, The Brain of the Bee. 149

They all form a promiscuous group that might be, but for lack
of a better knowledge of them and their cells of origin, may as
well not be, subdivided. Almost all of them are known only
from fragments of which those shown in plates XXI and XXII
are the best examples. Some of them may possibly even be
fragments of motor-fibers.

To these groups may be appended two others, one repre-
sented by the enormous fibers from the ocelli and the other by
the equally enormous fibers situated near the dorsal surface of
the ventral system and of the ventro-cerebron. They will be
considered in connection with the ocellar nerves.

THE CONNECTIONS BETWEEN NERVE FIBERS.

What facts I am able to bring forth bearing upon the
‘‘contact’’ idea and the old ‘‘ mesh-work ”’ idea of the fibrillar
terminations, though more properly considered here, I will de-
fer until I have described the mushroom bodies, in connection
with which the facts mentioned occur.

TRACHEA.

Besides these neural elements and the sheaths surrounding
some of them, there are to be found large numbers of trachea!
fibers. In bichromate of silver preparations they are the first
elements to become impregnated and then are brought plainly
into view. The larger branches may be very readily recognized
in hematoxylin preparations. Their general tapering form and
the time of their taking up the bichromate of silver prevents
their becoming confounded with nerve fibers.

To explain their origin it must first be noted that the brain
of the bee is surrounded by a number of tracheal sacs, the in-
ner walls of which closely cover it. Here and there tracheal
outgrowths from the sacs especially in the neighborhood of the
cell clusters pass into the brain. They branch more or less pro-
fusely among the cells and then send smaller branches into the
fibrillar substance as shown in fig. 29, Pl. XXII, which repre-
sents a camera drawing of the trachez of one of the mushroom
bodies. Trachez almost identical in appearance with these, are
found on all sides of the brain. Others, however, of a larger

150 JOURNAL OF COMPARATIVE NEUROLOGY.

size are also found that enter into the fibrillar substance more
deeply, and gain their entrance along with some nerve fiber or
bunch of fibers.

In no case have I been able to make out a tracheal net-
work such as described by Emil Holmgren (95) for the spin-
ning glands of lepidopterous larvae. So far as bichromate of
silver preparations thus far made show, the branchlets all termin-
ate independently of one another. In some of my copper-hema-
toxylin preparations there are, however, certain details that re-
call Holmgren’s figures which lead me to suppose that a
tracheal network may exist.

Special Description—the Proto-cerebron.

THE MUSHROOM BODIES.

From this hasty general account of the brain and its con-
stituent elements I pass to a more detailed consideration of its
parts and choose for the first the mushroom bodies as being the
most conspicuous and as the better serving for the orientation
of other parts later to be described.

These organs were first noted by Dujardin ( 50) in a study
of transparent preparations zz ¢ofo. From their slightly lobular
or folded appearance he compared them with the convolutions
of the human brain and described them as ‘‘lobes 4 convolu-
tions ”’ probably associated with the intelligence of the insect.
As will be seen in the sequel, this supposition has very much
more in its support than the crude or undeveloped morphologi:
cal technique of that time was capable of bringing to light.
Later they were again found by Leydig (64) who mentions
them under the term ‘‘Gestieltes Korper.”” They were again
described by Rabl-Rickhard (75) who, according to Viallanes
(7), first correctly described the calyx. But it was not until
Dietl ( 76) had applied microtomy and stained his sections with
osmic acid that a complete description of their whole structure was
obtained. Since that time they have been so often re-described
for insects representing the different orders of hexapods that
they may be considered as fairly well known structures very

Kenyon, Zhe Brain of the Bee. I51

characteristic of—especially the higher—hexapods. Special
swellings found on the brains of certain of the crustacea
have been compared with them, but it is to be seriously doubted,
I think, whether such swellings or cellular heaps are properly
to be homologized directly with them. In neither Retzius’
(90) figure of the brain of Astacus fluviatits nor in Bethe’s fig-
ures of the brain of Carcinus menus can I find cells having the
relations and the appearance of those that I find in the
bee. I have noticed nothing resembling the structures in
isopods, or amphipods, nor I have found indications of them in
the brains of Pauropus, Polyxenus, juloid diplopods, Scolo-
pendrella, Lithobius, nor even in several forms of Thysanura
that I have examined. If cells homologous with those filling
the cup-like calyx of the mushroom bodies of the bee are at all
present in these forms, they are so undifferentiated as to be in-
distinguishable from the general mass of cells about them.

The Calyx-Cup.

The four bodies that in the bee and the Hymenoptera in
general constitute what may be called the calyx-cup form the
upper portion of the proto-cerebron, and are arranged side by
side, a pair to each lateral lobe. In section, as shown in the
photographs of Plates XIV and XV and in optical section in
transparent unsectioned preparations, they are very noticeable
from the curved masses of fibrillar substance that form the base
and walls or calyx of each making them resemble optical sections
of so many cups. Each cup holds a mass of cells that fill it to
the brim. The walls of each lateral pair are nearly or quite
contiguous, except distally where they diverge from one another
leaving a space filled with a mass of small cells, as is also the
space between each outer cup and the inner fibrillar mass of
each optic lobe. Viewed from above they would appear elon-
gated antero-posteriorly or with their included cells as four folds
along the top of the brain, each extending backwards and in-
wards toward the median line. The inner one of each pair is
broadest anteriorly and somewhat overlaps its outer mate or
appears to crowd it back. On the other hand the outer one is

152 JouRNAL OF CoMPARATIVE NEUROLOGY.

broadest and extends the farthest posteriorly. Other general
details may be made out from the photographs. Below them
antero-laterally, below their whole posterior extent, or occupy-
ing the spaces between them and the rest of the proto-cerebron
are to be found ganglionic cells of various sizes, but mostly of
the small kind to be described elsewhere. There is also a small
mass of cells continuous with the mass between the upper por-
tion of each pair of cups, but which in the sections photo-
graphed appear to be cut off from the larger mass. Each fibril-
lar mass is outwardly clothed by a thin nucleated membrane.
These are the bodies described by Dujardin as ‘‘lobes

‘ ”?

a convolutions. By later writers they are _ variously
called. Leydig (64) described them as ‘‘Lappen mit Wind-
ungen ;” Rabl-Riickhard (75) as ‘‘ Rind Korper ;” Dietl ( 76),
Berger (7g) and Cuccati (gg) as ‘‘ Pilzhutformiger Kor-
per ;” while Newton ( 79) introduced the name calyx, which was
adopted by Packard (gg) and Viallanes (7 and gg).

The bodies reach their highest development in the Hymen-
optera and are much larger in the social wasps than in the
honey bee. In Jlatta the lateral walls of the cups are much
reduced, and in the Coleoptera the cup-like form is scarcely
recognizable, while in Forficula and Acridum the fibrillar sub-
stance only forms a broad plate. Even this is scarcely, if at
all, recognizable in Dytzscus. In Zabanus and Somomya the four
folds are reduced to two and in the former of these genera are
scarcely to be distinguished by a comparison of their cells with
those surrounding them. In the Hemiptera they are not dis-
tinguishable at all.

The Stalks of the Mushroom Bodtes.

From near the middle of the lower surface of each cup
a column of fibrillar substance passes into the main mass of the
proto-cerebron. In the bee these are much shorter than in
other forms. The inner one descends almost perpendicularly
downward fora short distance where it is joined by the one
from the outer cup, which is somewhat longer and has an in-
ward and somewhat forward course. In transverse sections the

Kenyon, Zhe Brain of the Bee. 153

columns or stalks present a nearly circular outline and are
distinctly delimited from the surrounding mass of fibrillar
substance.

The Roots of the Mushroom Bodies.

At the place of union of the two stalks there are given off
two masses of fibrillar substance of cylindrical shape, but with
a diameter considerably greater than that of the stalks. One
extends obliquely downwards towards the median plane of the
brain where it nearly abuts against the one from the opposite
side (fig. 2, Pl. XIV). Sometimes, as shown in the figure,
the point of one may slightly overlap the other. Like the
stalks, this structure is easily distinguishable from the surround-
ing mass of fibrillar substance even in ordinary preparations.

The other, which may be distinguished from the one just
described, or inner root, by terming it the anterior root, ex-
tends straight forwards and abuts against the peri-cerebral
membrane. It is longer than the inner root, but has nearly the
same diameter. In section it is nearly circular (fig. 1, Pl. XIV),
and in the transparent preparations zz Zofo appears as a circular
body in each proto-cerebral lobe, considerably above the an-
tennal lobe. For most of its course it is well delimited from
the surrounding mass, but anteriorly it becomes fused with the
surrounding fibrillar substance on its lower inner side. In this
region it may be seen to be entered by many irregularly branch-
ing fibers, even in preparations stained with haematoxylin (fig.
Tee ely SE):

THE MINUTE STRUCTURE OF THE MUSHROOM BODIES.

In sections cut in the frontal plane and treated with sul-
phate of copper and hematoxylin the cells filling the cups of
the mushroom bodies appear to be of two kinds, both arranged
one above the other so as to present the appearance of tiers ar-
ranged more or less radially with respect to the calyx as a cir-
cumference. Laterally they are much larger than those in the
middle, which in such sections forma dark colored triangle
(fig. 1). Those at the side are much lighter. In sections
of brains fixed and colored in von Rath’s platino-osmo-picric acid

154 JOURNAL OF COMPARATIVE NEUROLOGY.

mixture the contrast between the two kinds is noticeable only
upon close inspection and then only as a difference in size.
After staining with fuchsin brings out no further difference.
The chromatin elements then appear more distinct and more
numerous, but both seem equally well supplied. Nor is there
a difference in the presence or absence of a small dark colored
nucleolus in preparations treated after the copper-hematoxylin
method. The slight chemical difference indicated by the differ-
ence in depth of coloring shown by the latter method is, how-
“ever, supported by a difference in the fibers given off from the
cells, as will be seen a few lines further on.

In similar sections of the brain of a wasp I find but one
size in the cells of this region. But two sizes occur in the
- cockroach according to Flogel (7g) and are doubtless to be
found in other forms. But one or two kinds, the cells of the
mushroom bodies in the hexapods generally, and of the regions
compared with them in crustacea, are strongly distinguished
from nerve cells elsewhere in the brain, and in the whole nerv-
ous system for that matter, in being nearly devoid of extra-nu-
clear protoplasm. This fact led Dietl to term them ganglionary
nuclei, a term that was later altered by St. Remy (99) to the
-equally characteristic one of chromatic cells.

Between the tiers of cells fine fibrils and trachea make
their way to the inner surface of the cup, the trachez also
branching among the cells as already described or figured in
Plate XXII (fig. 29). The nerve fibers may be traced, with
considerable difficulty, however, tc the cells. In bichromate-of
silver preparations both cells and fibers easily impregnate and
where the section is in the right place or where too many elements
have not become darkened, the fibers are readily traced into the
fibrillar substance forming the calyx-cup (fig. 18, Pl. XXI),

Here the fibers from the larger or marginal cells break up
into a series of fine branches that again subdivide and produce
a bushy or arborescent formation that reaches to the outer wall
of the calyx and of which the drawing (fig. 18, Pl. XXI), al-
though made with a camera, can give but a poor conception.
The preparation from which this drawing was made is one of

Kenyon, Zhe Brain of the Bee. 155

the first that were fairly well impregnated, but not so well as
later ones, and is far from showing the richness of branching
seen in the latter. Further, the branches are delicate and the
smaller ones covered with fine short processes that give the
whole a more or less feathery appearance. The preparation is
not black, but of a delicate reddish brown tint. The difficulty
of representing them and the fact that the connections with the
cell bodies are poorly represented in the other preparations
caused me to be satisfied with the figure given.

The processes of the smaller cells forming the pyramidal
central heap, as shown in the same figure (fig. 18, Pl. XXI),
also pass into and branch in the fibrillar calyx-cup. These
branches resemble those of the other fibers, but, as shown, are
far less numerous. Moreover the processes from the cells may
be slightly smaller.

As shown in the figure, the processes do not always follow
the most: direct line to the fibrillar substance, but seem often to
bend about the intervening cell-bodies. Consequently little de-
pendence can be placed upon even the best of preparations by
ordinary methods for tracing fibers for any considerable distance
from the cell body towards the fibrillar substance. Fibers may
readily be seen, however, passing from the cellular mass into
the calyx, for between the two there is a narrow space but
loosely filled with fibers, which may be seen more or less indis-
tinctly in the photographs.

In this space are to be seen small round deeply stained
bodies, which upon close examination and by comparison with
sections cut in a plane parallel to the inner walls or to the base of
the calyx are seen to be composed of a large number of very fine
fibers arranged parallel to one another and forming thus a close-
ly crowded fiber tract. These radiate in all directions from the
place of union of the calyx and the stalk from which they seem
to come. Outwardly the fibers separate and gradually spread
out over the whole inner surface of the cup. Such phenomena
are best shown in bichromate of silver preparations, but may be
seen in preparations by ordinary methods and have been fig-
ured by earlier writers (Viallanes, Cuccati).

156 JOURNAL OF COMPARATIVE NEUROLOGY.

A further study of bichromate of silver preparations will
show that each fiber from one of these bundles after its separa-
tion from the rest becomes continuous with a fibrillar process
entering the calyx-cup from one of the cells above. Thus there
is formed a nerve cell of the general Y-type (fig. 18, Pl. XXI).
No other nerve cells are found in the cups.

Before continuing the consideration of the fiber just noted
it may be well to mention the form of the cell bodies here and
of those elsewhere. The larger number of successful impreg-
nations of the cell bodies of the cups present a perfectly smooth
outline. Very many, however, have from one to five or six
projecting processes, which may branch. In this respect the
smaller cells of the pyramidal group are exactly like the larger
border cells, though such a condition did not happen to be
shown in the section from which figure 18 was drawn. To de-
termine whether they differed in this respect the sections of sev-
eral brains were examined, resulting in the conclusion just given.
Many of the cells resembled those shown in figure 19, Pl. XXI.
Whether these processes are protoplasmic continuations of the
cells to which they are attached or whether they represent
merely filled up adjacent inter-cellular spaces, is a rather difficult
question to answer. Here is one of the most serious difficulties
presented by the bichromate of silver method. A few such
cells I have seen in the optic lobes, but there as elsewhere cells
with smooth contours seem to be the rule, and the rule might be
taken to indicate an artifact nature for the processes in
question. Further than this I find no reason for believing
them to be artifacts. On the other hand, the fact that there
was no evidence of undoubted artifacts in the immediate neigh-
borhood of the cells described, together with the peculiar cir-
cumstance of the extremely small amount of extra-nuclear pro-
toplasm in the cells filling the cups and their generally crowded
appearance, would indicate that probably the processes are real-
ly parts of the cells with which they are connected.

Returning to the fibers of these cells, it may be noted that
it is the bichromate of silver method alone that is able to show
their course and termination. Fortunately there is no difficulty,

Kenyon, The Brain of the Bee. 157

such as there is with the fibers of other regions, in determining
their immediate relationships completely. The bundles of fibers
already mentioned as radiating from the place of union of the
calyx and stalk as though coming from the latter do so, or
rather, to start from the parent cell, pass down into the stalk.
At the junction of the stalk and the two roots each fiber divides
into two branches one of which passes obliquely downward
towards the median line, the other straight forward to the an-
terior surface of the brain. Both terminate without further
branching, and the inner group form the inner root, and that
directed forward the anterior root of the mushroom bodies.
Throughout their whole course from the entrance into the stalk
to their termination in the inner and the anterior roots the fibers
remain parallel, the only deviation from a straight line being
a slight waving. They neither decrease nor increase in size
but in the stalk they sometimes, though not always, ap-
pear to be covered by fine short processes that can neither be
described as thread-like nor tooth-like. These may be arti-
facts, but I am inclined to think that their non-appearance
might as well be accounted for by defective impregnation.

There is found, then, in the mushroom bodies a nerve cell
with a smooth or irregular body sending a process into the
fibrillar substance forming the calyx, branching there profusely
aud sending a second process from the first down through the
stalk and forming an inner and an outer branch. As will be
seen beyond all doubt a little farther on, the branching process
in the calyx is the dendrite and the second process is the neu-
rite. In the relation of its neurite to other fibers it recalls to
some extent the relation between the neurites of the cells of
the granular layer and the dendrites of the cells of Purkinje in
the mammalian cerebellum, but as a whole the cell seems to be
unique among all known nerve cells.

Fibers Ending in the Calyx.

In bichromate of silver preparations, besides the branch-
ing dendrites of the cells just described, there may also be seen
a large number of other fibers all somewhat coarser than the

158 JouRNAL OF CoMPARATIVE NEUROLOGY.

fibers of these cells and permeating and branching in the calyx
in all directions (figs. 23, 26, 27, Pl. XXI). Often they are
impregnated almost to the exclusion of the fibers from the cells
above. At other times both appear, but then they most often
obscure one another, making it necessary to section a large
number of brains in order to find cases sufficiently free from a
repetition of details to enable one to determine the form and
relationships of the various fibers correctly. When such cases
occur it is found that the fibers terminating in the calyx all
.-make their entrance in the neighborhood of the junction of the
calyx and stalk, or from the under surface of the cups. All
appear to send a main fiber in a circle about the head of the
stalk and from this to radiate numerous branches to the more
distant parts.

The difference in size and mode of branching of these en-
tering fibers allows two kinds to be distinguished. In the
smaller kind of branches radiated from the region of the stalk,
one slender kind branch more or less irregularly and repeatedly,
terminating finally in an irregular swelling such as shown in fig.
27, which represents a magnification of about 583 diameters.

The larger kind (fig. 23) radiate off from the portion en-
circling the head of the stalk a number of stocky branches that
after penetrating the surrounding mass of fibers for a relatively
short distance branch out into a cymose head. Other portions
aparently of this same fiber pass out into more distant parts of
the calyx. The figure given was drawn with as much care as
possible and well represents what was seen, but appearances
are often deceptive, and I am inclined to think there are two
kinds of fibers here instead of one as represented. It may
happen that fibers overlie one another in such a way as to ap-
pear as one continuous fiber, a deception that, especially in
thick sections, the most careful focusing will not always avoid.
The fibers shown in the figure as immediately surrounding the
junction of the stalk and calyx appear to be restricted to the
region covered by the median group of small cells. The others
appear to have gained an entrance to one side of the stalk and

Kenyon, The Brain of the Bee. 159

take in a larger region, besides appearing to have a different
mode of branching.

The difference in size between figs. 23 and 26 is mostly a
difference of magnification, which in the former is 121 and in
the latter a 102 diameters, yet the fibers represented in fig. 23
are actually the coarser.

Just where either of these two kinds, the fine and the
coarse fibers originate, or what other parts of the brain are con-
nected with the mushroom bodies by them is yet to be deter-
mined. Almost all that can be said is that six different tracts
of fibers terminate here, two from the optic lobe, one from the
ventral region, and three from the antennal lobes. To these
may probably be added a seventh of a commissural nature.
These tracts will be described further on.

The Fibers Ending in the Stalk and the Roots.

In certain places (fig. 1, Pl. XIV), as already pointed out,
fibers entering the anterior roots of the mushroom bodies may
be very readily seen in sections treated after the copper-hama-
toxylin method. In preparations by the bichromate of silver
method others may be distinguished. One large tract traced
to its cells of origin behind and between the stalks of the mush-
room bodies by Viallanes (87) in his study of the wasp spreads
out on the side of the anterior half of the anterior root and
branching sends one branch into it. The fibers of this
pass nearly horizontally across or obliquely downwards to the
opposite side giving off from their upper side several sub-
branches (fig. 21, Pl. XXI) that after passing a greater or less
distance upward break up into a thickly bushy head. These
all occupy almost the same level so that often in specimens
treated with osmic acid or with hematoxylin, especially the
latter, the appearance is presented of several bands crossing
transverse sections of the roots. Figures 3 and 4 show these
bands excellently, and represent the two roots as seen in a
slightly oblique section treated with copper sulphate and a so-
lution of hamatoxylin made according to one of Weigert’s for-
mulz. Bands of this sort occur throughout the whole extent

160 JourNAL oF COMPARATIVE NEUROLOGY.

of the root. In the inner root also similar bands, though less
conspicuous, are found, but there instead of being transverse,
they are longitudinal.

The fibers just described are more or less coarse, consider-
ably more so than fibers entering the lower outer side of the
root behind them (fig. 28). The sub-branches of the second
kind of entering fiber also take an upward course and break up
into a series of branchlets, which do not, however, form a com-
pact bushy head. Where their cells of origin are situated Iam
unable to say further than that subsequent studies will probably
show them to be situated somewhere beneath the calyx-cups,
either to one side of or behind the stalks. Their outward-go-
ing branches seem to penetrate into the lower lateral depths of
the brain. A third fiber enters this same region at a lower
level and appears to come from the lower lateral side (fig. 28).

Behind these fibers near the junction of the roots, or in the
plane shown in fig. 1, Pl. XIV, onthe left, fibers are found
entering on the lower inner side which present a more delicate
appearance and are otherwise different from those first described
(fig. 28). They branch more or less dichotomously and end in
a tuft of branchlets which in preparations with osmic acid or
hematoxylin give rise to the broken appearance shown in the
section of the left root in fig. 1, a comparison with which will
show that fig. 28 is not properly oriented and that it should be
viewed from the corner of the plate so as to make the branches
crossing the dotted ring take a nearly horizontal course.

In the region of the junction of the two roots and the two
stalks rather coarse fibers are found (fig. 17) considerably resem-
bling those first described, whose more or less bushy terminals
along with those last described produced the knotted appear-
ance described by Rabl-Rickhard (75) for the ant as ‘‘ 2-3
small clefts rounded off above,” and the lenticular spots only
faintly shown in fig. 2. The same appearance as that described
by Rabl-Riickhard is found in the bases of the stalks in the bee,
but the section represented in fig. 2 is too far back to show it.
To imagine the figure, however, all that is necessary is to sup-
pose the lenticular spots to be larger and united at their bases.

Kenyon, The Brain of the Bee. 161

The lighter places between the spots are filled by the fibers of
the mushroom body cells alone (fig. 17).

In the stalk my preparations show the existence of incom-
ing fibers resembling the upper ones represented in fig. 28
more than any of the others. But details are not sufficient to
enable one to determine their origin or the destination of their
outer branches any better than, in fact not so well as, those en-
tering the anterior root.

Very nearly the same thing may be said with respect to
the fibers entering the inner root. Some of these appear to be
connected with the central body later to be described, others
seem to come from the opposite lower side of the brain. Their
branches in the root are of the same general type as those rep-
resented in fig. 21, but the sub-branches are much shorter,
more uniform, and end in avery much more compact head of
branchlets. These of course cause the longitudinal banded ap-
pearance already mentioned.

Besides these six or seven groups of entering branches
there are to be found numerous fibers irregularly branching over
the surface or near the surface of the roots, which may also send
small branches into them (fig. 22, Pl. XXI), and here may be
noted a fiber seen in one section only that is of no little in-
terest. Whether it belongs to any of the regular groups I am
unable to say definitely, but think from its appearance that it
must be a branch of one of the irregular fibers just mentioned.
It is figured on plate XXI (fig. 25). It enters the right ante-
rior root near its terminus from some little distance in the lateral
part of the brain and is there of considerable size. But almost im-
mediately upon entering it decreases in volume and after branch-
ing becomes connected with the neurites of the mushroom body
cells. The junction appears as complete as though there existed
here a veritable fusion. So fine are the fibers that the prepar-
ation also seems to show that the parallel fibers from the mush-
room body cells have branches in this place. The latter condi-
tion cannot, however, be the true one, for in all other prepara-
tions, which are numerous, no such branching is shown. With
Lenhosseék ( 95) I agree that in general the bichromate of silver

162 JOURNAL OF COMPARATIVE NEUROLOGY.

method, usually showing only silhouettes, is defective and very
apt to mislead in the matter of fibrillar connections. But in the
specimen in question viewed with a Leitz ocular No. 2, and ob-
jective No. 5, there is no more reason for doubting the contin-
uity of the lines shown than there is in fibrils shown in prepar-
ations stained with hematoxylin or any other histological color-
ing matter. They are not superimposed, nor is there any reason
for thinking them to be of tracheal nature.

When we consider the nature of the method used, it should
not appear strange that fibrils in very close contact should be so
impregnated with bichromate of silver as to cover up all evi-
dences of separation. In fact it seems to me that such apparent
evidences of continuity are to be expected, without, however,
even raising a doubt as to the complete validity of the evidence
obtained from the generality of terminations shown and from
histo-ontogeny.

Before leaving the matter it must be noted that, although
the figure given is a camera drawing made with the aid of care-
ful focussing, it does not correspond with what appears when the
camera is removed. Then the fibres a, d and ¢ are seen to belong
to the parallel fibres which are continued upwards beyond their
junction with the fibrillar branches of the incoming fiber.

THE FUNCTION OF THE NERVE-CELLS OF THE MUSHROOM BODIES.

Ever since Dujardin (59) discovered the mushroom bodies
and pointed out the relation between their size and the develop-
ment of insect intelligence, nearly every writer on the subject
of the hexapod brain who has referred to the matter of intelli-
gence has recognized the fact. Leydig (64) thought them con-
nected with the intelligence of the animal, but added that they
also seemed to bear some relation to sight, or to the ocelli. Rabl-
Rickhard (75) thought the same, except that he pointed out
that Leydig’s second supposition is incorrect, since in blind ants
the bodies are found to be well developed, while the optic
lobes and the nerves of the ocelli are absent. Forel (74)
pointed out the same facts and added that the mushroom bodies
are much the largest in the worker ant, and that those in the

Kenyon, The Brain of the Bee. 163

female are larger than those in the male. Two years later
Brandt (76) affrmed the same condition to be true for the Hy-
menoptera generally. Berger (78) agreed with Dujardin and
the rest. Dietl (76) was inclined to dissent, and Flogel (7s)
seemed to consider the roots and stalks as a framework (Geviis?)
for the rest of the cerebral substance. Nevertheless the tabu-
lar summary of his study on the different orders that he gives at
the end of his paper is of no inconsiderable value in showing the
truth of Dujardin’s inference, so far as comparative anatomy is
able to do so. The physiological experiments of Faivre (57)
and others, which have lately been repeated and perfected in the
excellent work of Binet (94), are of great value in showing that
the seat of intelligent control of an insect’s movements is in
the dorso-cerebron. Thus far, however, no attempts seem to
have been made to determine experimentally the function of the
mushroom bodies as parts distinct from the rest of the dorso-
cerebron. Experiments are badly needed to complete our
knowledge of the structures.

All that Iam able at present to offer is the evidence from
the minute structure and the relationships of the fibers of these
bodies. This seems to be of no inconsiderable weight in sup-
port of the general idea started by Dujardin. For in connec-
tion with what was made known by Flogel and those before him
and has since been confirmed and extended by other writers,
one is able to see that the cells of the bodies in question are
much more specialized in structure and isolated from the gen-
eral mass of nerve fibers in those insects where it is generally
admitted complexity of action or intelligence is greatest. Con-
sidering the calyx and the cells above it alone, one finds that
according to Flogel neither are recognizable in the Hemiptera,
that in Diptera (Zabanus) and Odonata (deschna) the bodies
are recognizable from those in the neighborhood only by a
slight difference in the size of the cells representing them ; that in
Lepidoptera the calyx-cup is very small or entirely absent, that
in the Coleoptera (Zenthrido, Cynips) the calyx is not so ex-
tended as to be very well recognized asa cup, and that in the
Orthoptera the lateral walls of the cup are either very small

164 JOURNAL OF COMPARATIVE NEUROLOGY.

(Blatta) or entirely absent (Forficula, Acridium, etc.) ; while in
the Hymenoptera the calyx is folded upwards so as to give
room for many more neural elements and connections.

If one considers the little that has thus far been made known
by means of the bichromate of silver and the methylen-blue
methods concerning the cerebral nerve fibers in other inverte-
brates, one finds that sensory stimuli are transferred to a num-
ber of irregular cells or fibers distinguished roughly by the term
association fibers and from these transferred to motor or other

_fibers bearing efferent neural impulses. And from such a com-
parison it appears that in the groups of insects certain of these
association fibers have gradually been set apart from the rest so
as to render it possible for an entering stimulus to become an
efferent impulse by taking a direct or an indirect course. In
the former case the course is to be compared with the course ofa
stimulus producing reflex action in man. Later on it will be
seen that the present assumption of the existence of fibers per-
mitting such a course is fairly well founded. Thus a sensory
impulse from an optic lobe or from an antenna may reach .the
fibers going to the mouth parts through possibly but one asso-
ciation fiber,

In the other case it may take a special or somewhat indi-
rect course to and through the fibers of the cells of the mush-
room bodies and from them reach the efferent fibers through
the processes of one or more association cells. From those facts
it seems far within the bounds of reason to suppose that the
nerve cells of the mushroom bodies rendered so prominent by
their specialization of form and position are the elements that
control or produce actions that one distinguishes by the term
intelligent.

An analysis of these actions is needed, but that is beyond
the limits of this paper. Suffice it to point out that the exper-
iments of Binet (94) and others show that when the connections
between the dorso- and ventro-cerebron are destroyed the phe-
nomena afterwards observed are similar to those seen ina
pigeon or mammal when its cerebral hemispheres are removed.
One difference is notable, namely, that the operation of eating

Kenyon, The Brain of the Bee. 165

in the case of the insect appears to be reflex ; for when one, vivi-
sected as just indicated, is placed upon its food it begins and con-
tinues to eat. In the other case the animal must be fed. The vari-
ous bodily movements of the insect, however, after a time take it
away from the food, and once away it is wholly unable to return.
Such insects when passing food even almost within touch of their
palpi are wholly unable to change their course so as to secure
it, although the movements of their palpi plainly show that its
presence has affected them. Whether this would still remain
the case when the vivisection is of sucha nature as to allow
sensory stimuli from the antenne or visual stimuli to act through
the reflex channels already mentioned is as yet unknown. From
a consideration of the facts that I have pointed out and the
facts demonstrated by comparative anatomy and embryology
relative to the homologies of the antenne one is warranted in
expecting that the animal would still lack the power of drecting
its movements.

THE CENTRAL BODY.

This peculiar body was first made known by Dietl ( 76) as
‘the fan-shaped structure,’” and was two years later described by
Flogel (78) as the central body, a term that has since been gen-
erally employed. It lies above and behind the ends of the inner
roots of the mushroom bodies and is wholly composed of large
nerve fibers and fibrillar substance, plus, doubtless some tra-
chealclements (tgs. 2,.5,°0,.7, 9, O,.G0.). ) Antew of its, con:
nections I have been able to ascertain, but very much yet re-
mains to be learned, so much in fact that any assertion as to its
functions can be but little better than a mere guess. Viallanes
(87) describes it as connected with all the surrounding parts of
the brain, but that is an assertion too sweeping for the facts
known to me after an application of the bichromate of silver,
the copper-hematoxylin and platino-osmo-picric acid methods,
and was much too sweeping for the actual facts known to Vial-
lanes. Berger (78) recognized the body in Dytiscus as a lenti-
cular body receiving a bundle of fibers from each side which
entering broke up into its individual fibers, some going

166 JOURNAL OF COMPARATIVE NEUROLOGY.

out anteriorly, some posteriorly, or, in short, as a center of
disassociation.

The body throughout my diagrams and figures is distin-
guished by the letters c. 0.

In the honey bee this body as a whole has a very much
distorted spherical shape. In frontal sections the fan-shape
described by Dietl and Berger is apparent (fig. 5), though the
outline presented might be better described as reniform. Viewed
from above or in horizontal sections it has a somewhat trape-
zoidal outline.

_ Internally, as shown by sections in the frontal plane, it is
divided by a space filled with nerve fibers and trachez, into an
upper and larger portion covering a lower and smaller portion.
Both are seen in preparations by ordinary methods to be cor-
posed of fibrillar substance, but in frontal sections the lower
usually stains more deeply (fig. 5). Antero-posteriorly the
upper portion is also much the larger and considerably over-
hangs the other, partly covering two masses of fibrillar substance
a little farther on to be described as tubercles. :

Taken as a whole, fibers seem to reach it from or leave it
in nearly all directions ; but the two parts seem to be supplied
somewhat differently. Those entering the lower are seen to
originate from cells above the antennal lobes and upon reaching
the lower lateral edges to take a transverse course below the body
and send several branches upwards that subdivide arborescently
producing a compact mass of branchlets that recall the arborescent
and bushy terminations of the association fibers in the roots. of
the mushroom bodies (figs. 32 and 37). As in the case of these
latter fibers, it is to the compact branching mass of fibrills
that is due the depth of color so noticeable in preparations
stained with osmic acid or with hematoxylin. Other fibers
either pass out or enter from the fibrillar substance of the brain
immediately in front, while branches from association fibers in
the anterior region seem to enter the anterior end and the
posterior lower end of this portion of the body (fig. 40, PI.
XXII).

In the upper portion the same arborescent method of

Kenyon, Zhe Brain of the Bee. 167

branching also occurs, and gives rise to the wavy upper contour
shown in figs. 5 and 6. But here the fibers originate from cells
above the body in the median plane or from cells behind it and
after passing behind the body enter the cleft separating the two
portions, where many of them are gathered into bundles with an
antero-posterior course. These recall the radiating bundles seen
in the cups of the mushroom bodies. Other fibers also send their
branches into it from its outer surface (Pl. XVIII).

Just behind the inner roots of the mushroom bodies large
numbers of fibers seem to be given off, some of which pass
downwards to the neighborhood of the cesophageal foramen,
while others take a more lateral course (fig. 5). It is this ap-
pearance, which is very noticeable in preparations by ordinary
methods, that doubtless led Viallanes to make the assertion re-
ferred to. When impregnated with bichromate of silver these
fibers seem to originate from cells situated somewhere behind
the central body and, after passing over its surface and sending
branches in to it, to take the course described and shown so well
in fig. 5. Some of them are probably the neurites of a group
of cells whose dendritic branches form a commissure immedi-
diately behind the central body (fig. 9, Pl. XVI) and send their
sub-branches into its posterior surface (Pls. XVII and XVIII,
cells 5 and 6).

Another group of cells lying above the body in the me-
dian plane send their processes backwards over its surface and
after sending a branch to what will soon be described as the
fibrillar arch pass down behind and enter the space separating
the upper and lower portions of the body and branch in the form-
er portion (cell 2, Pl. XVIII). Fibers from cells situated behind
the body and above the fibrillar arch also make the same con-
nections. Another group of fibers originating from cells above
the antennal lobes pass obliquely inwards to the space just be-
hind the lower half of the body and passing upward in front of
the glomerules end in the upper half. What connections are
made by them I have not thus far been able to ascertain. No
fibers passing between any portion of the central body and the
calices of the mushroom bodies have been seen, and whatever

168 JOURNAL OF COMPARATIVE NEUROLOGY.

indications have been noticed of connections with the inner
roots of these bodies are of such a fragmentary and otherwise
imperfect nature as to render their existence very doubtful. All
that may be safely said is that it is connected with the fibrillar
arch, possibly the ocellar glomerule, with the mass of associa-
tion fibers immediately in front, with the lower lateral regions
of the proto-cerebron, and with the trito-cerebral region form-
ing the cesophageal commissure, where its fibers may possibly
connect with others entering from the ventral cord, or with
' those belonging to the ventro-cerebron.

THE TUBERCLES OF THE CENTRAL BODY.

Behind the lower portion of the central body and partly
covered by the overhanging upper portion (fig. 6, Pl. XV) are
two small round, deeply staining masses of fibrillar substance to
which. Viallanes (§7) applied the term of ‘‘tubercules du corps
central.’ Just what their relations are to the central body, or
what may be the origin of the fibrils forming them I have not
been able to determine definitely. But from the fact that in
thick unstained sections one can distinguish in the immediate
neighborhood behind them masses of fibrillar substance of a sim-
ilar globular appearance I am inclined to think them globules of
the same kind and having the same or similar relationships as the
latter. My preparations do not satisfactorily show fibers leading
into or going from them. But there are indications that the mass
of smaller glomerules is formed by terminations of the nerves
from the ocelli very much as the so-called olfactory glomerules
later to be described are produced by the terminations of the
fibers from the antennae, and for that reason I choose to call
them ocellar glomerulz. This particular region of the brain
along with the central body needs considerably more light than
I am at present able to throw upon it.

THE FIBRILLAR ARCH.

This peculiar structure may as well be considered here,
since it is connected with the central body, behind which and
somewhat below the level of whose upper surface it lies. It is
a rod-like mass of fibrillar substance that upon either side rises

Kenyon, Zhe Brain of the Bee. 169

from but is scarcely connected with, the mass of fibrillar sub-
stance behind the union of the roots and stalks of the mush-
room bodies and passes directly across the median line through
the large mass of cells filling the posterior median furrow, thus
forming a sort of commissure described by Viallanes (7) as

y

‘‘le pont du lobes cerebraux.”” It does not form a commis-
sure, such as is ordinarily understood by the term, even though
it connects the two lateral halves of the brain, and seems much
better denominated by the term ‘‘gabelformiger Korper’’ em-
ployed by Cuccati (ss) or better still by the one that I have used.
The central portion of the arch may be seen in figure 8, while
in figure 9, several sections below, the pillars upon which it rises
appear as two dark spots, one on either side of the enormous
nerves from the ocelli.

In preparations treated with copper-sulphate and hama-
toxylin or by the platino-osmo-picric acid method of von Rath,
large nerve fibers may be distinguished passing irregularly along
its outer surface, and seemed to originate from cells situated on
both sides of the brain near its ends. Viallanes (87) mentions
fibers passing from it to the central body, a connection that as
already intimated my preparations with bichromate of silver
show to actually exist. A group of fibres from cells in the
median plane above the central body send each a short branch
that ends here in a tuft of branchlets (fig. 2, Pl. XVIII) and
then continues on down into the central body as described when
speaking of that structure. This short branch and its tuft-like
ending without doubt represents the dendrite and the larger
branch to the central body the neurite of the cells of this group.
Other groups situated above and both before and behind reach
the central body after branching in exactly the same manner.
Vialianes (g7) supposed that possibly the structure received
branches from the ocellar nerves, but was far from being sure.
Whether his supposition is true my preparations thus far made
do not enable me to decide definitely, but from the fact that
the nerves in question seem to begin to break up or become
less numerous in this region and from a few indications in bichro-
mate of silver preparations I am inclined to think that possibly

170 JOURNAL OF COMPARATIVE NEUROLOGY.

his supposition will sometime be found to be true. What con-
nections are made by the fibers mentioned as covering the outer
surface of the structure, I am not prepared to say.

THE ASSOCIATION FIBERS OF THE PROTO-CEREBRON.

The fibrillar substance of the regions surrounding the
bodies already described, or the rest of the central proto-cere-
bron, is composed of the association fibers coming from, and the
tracts of fibers going to, these bodies, together with bundles of
, fibers entering it from various groups of cells and giving rise to
a great number of irregular fibers to be classed under the gen-
eral term of association fibers. In only a few cases have the
cells from which these fibers originate been impregnated along
with their fibers so as to make their relationships perfectly clear.
What little has been learned I have endeavored to bring out in
the diagrams that follow as well as in the camera sketches in
the last two plates.

The fibers, as may be readily seen in fig. 1, take various
courses, binding the upper, the lower and the lateral parts to-
gether. Fibers originating from cells above the antennal lobes
pass up on the inner side of the anterior roots of the mush-
room bodies and branch arborescently in the region just above
them (fig. 31 and fiber 10 in the diagrams). Just below the
root a small branch is given off that passes outward horizon-
tally. Other fibers seen in preparations by the copper-hema-
toxylin method in front of the plane of fig. 1 seem to originate
from cells above the antennal lobes, and, after passing upwards
near the median line as rather large fibers, bend over the ante-
rior roots of the same side and become lost in the fibrillar sub-
stance (Pl. XVII). The fibers of the cells in the median line
under the edges of the calyx-cup and in front of the central body
also seem to branch in this region, for I find no indications of
their forming a chiasma and passing into the lower regions of
the brain as described by Viallanes (84) for the Orthoptera,
and by Cuccati (ss) for Somomya. Other fibers of unknown
origin (fig. 40, Pl. XXII), but of a very conspicuous appear-
ance branch rather profusely in this region of the fibrillar sub-

Kenyon, The Brain of the Bee. Tear

stance and send branches back into the central body. Others
bend over the inner roots and send branches upwards and across
to the region immediately above the base of the anterior root of
the opposite side (fig. 32, and fiber 50, Pl. XVIII). Another
seems to arrive, (whether from over the top of the central body
or from somewhere beneath the calyx-cup, is difficult to decide, )
and branches near the junction of the two roots, one branch
going toward the central body, the other straight downward
(fiber 21, Pl. XVII). A similarly perpendicular fiber is also
found on the outer side of the root (fiber 20, Pl. XVII). Still
another (fig. 32) seems to arise as a small fiber from over the
central body, passes downward to the opposite side, where it
becomes much enlarged, and gives offnumerous branches, these
even passing out under the anterior root. It may possibly be
one of a group of fibers (fiber 49, Pl. XVIII) originating from
a group of cells near the fibrillar arch and passing directly for-
wards over the central body.

A horizontal fiber (fig. 22, Pl. XXI) originates somewhere
at the side of the brain and after giving off several branches
that spread out over the top of the anterior root ends in an ar-
borescent system of fine branchlets in the upper part of the
middle portion of the cerebron just across the root.

The fibers connecting the anterior and posterior region are
most striking in appearance and are of considerable extent.
One (fig. 30) apparently originates from cells in the region
above and behind the antennal lobe and passes backward to one
side of the median plane giving off a branch that subdivides
and passes to the median anterior root, one passing up close to
it and the other to a lower level. After giving off this branch
it becomes very much smaller and passes on backwards, giving
off several small branches meanwhile. Near the posterior
wall it divides into two branches of small size, but of consider-
able length, the one going directly upward and_ branching
among the ocellar glomerule, the other directly downward into
the cesophageal commissure and the ventro-cerebron.

Another fibre (48) equally, if not more peculiar, is shown
in figure 34. This appears to originate from a cell situated

172 JOURNAL OF COMPARATIVE NEUROLOGY.

behind the inner root of the mushroom bodies (providing one
may judge from the appearance of the fiber and the direction
of its branches). Just behind the inner root and to one side of
the base of the central body it becomes very much enlarged,
gives off two relatively short branches and then one long one
that passes up over the inner root and over the anterior root
just in front of the junction of the two with the stalks, as shown
by the dotted lines in the figure. Another branch a little fur-
ther forward passes up to and branches in the fibrillar region to
‘one side of the central body, while in front of this a number of
short branches are given off that branch very profusely in the
region to one side of the base of the central body. The main
fiber continues forward to the neighborhood of the antennal
lobes giving evidence of further branching, but on account of
being either unimpregnated or cut off can not be traced farther.

The fiber shown in figure 35 is nearer the median plane
and appears to come from the cesophageal commissure, passing
upward and then directly forward under the central body, giv-
ing off along its course several branches that run back into or
towards the commissure and then four very long though small
branches that pass upwards in front of the central body ending,
so far as can be traced, above the level of the top of the latter.
One of the four passes farther forward and gives off a branch
that turns back into the neighboring region to one side.

In figure 33 a more peculiarly twisted fiber (35) is shown,
which was found in the lateral region of the proto-cerebron be-
low and to one side of the anterior root and behind the optic
body, near which it may possibly originate. Its base is
at the right of the figure. It passes outwards for a short dis-
tance then backwards, gives off a branch that turns upon itself,
divides again several times, some of the branches going up-
wards, the rest downwards and forward. There it passes down-
ward for a short distance and divides into two large branches of
almost equal size, one going backward, so far as traceable, ap-
parently to the posterior region of the brain, the other forward,
twisting above the parent stem and finally breaking up into a
number of branches that terminate behind the central body.

Kenyon, The Brain of the Bee. 173

The Deuto.cerebron.
4 THE ANTENNAL LOBE.

The antennal lobes comprise by far the larger portion of
this division of the insect brain, especially so in the honey bee,
and the rest of the Hymenoptera for that matter, where the
remaining small portion is so fused with the proto- and the
trito-cerebron as to leave little or no trace of separating
boundaries.

Considering first the antennal lobes, one may say that sec-
tions cut in various planes show that each lobe is composed
internally of a nearly spherical mass of fibrillar substance con-
nected with the rest of the brain by a small neck of the same
substance and surrounded on all sides by a large number of cells,
some of which belong to it and some to the proto- and the
trito-cerebron, and fill in the deep spaces between it and these
two parts. Inside of this sphere and near or composing its
periphery one finds small globular masses that by any of the
ordinary methods of staining take a much greater depth of
color than the more internal part, and in them one recognizes
the great non-nucleated cells of Leydig (64) and Rabl-Rick-
hard (75), which were first more correctly described by Dietl
(76) as olfactory bodies. Flogel (7s) claims the honor of point-
ing out their true significance, for, he says, he called attention
in an unpublished communication to the Kieler Physiologische
Vereins, July 30, 1874, to the fact that they are not cells.
Fig. 1 shows the bodies or glomerule very plainly.

Between them even in ordinary preparations processes from
the bordering cells may be traced to the inner fibrillar sub-
stance, but it is doubtful whether branches entering them may
be seen in such preparations. Cuccati (ss) regarded them
along with the rest of the mass as made up for the most part
of branches of these processes that by subdividing formed with
whatever other fibers that might be there a sort of net work.
The only difference that he supposed to exist between them and
the central portion of the mass was in the greater fineness of
the meshes of the net. But while his supposition with respect

174 JOURNAL OF COMPARATIVE NEUROLOGY.

to the relation of the glomerule to the surrounding cells is cor-
rect and even though some of my preparation are so strongly
impregnated with bichromate of silver as to present consider-
able resemblance to a meshwork, I am inclined to believe other
preparations showing a tuft-like system of branching illustrate
the true condition (fig. 10 and 16, Pl. XXI), and that the idea
of connection by contact holds as well here as elsewhere. As
already pointed out cases might occur in such _ prepara-
tions in which the darkened fibers might appear perfectly con-
' tinuous, so as not even to be explained by Lenhossék’s sugges-
tion of a silhouette of superimposed fibers, and still not be
fused or continuous. Happily such deceptive appearaces
seem to be rare except in too heavily impregnated preparations.

When impregnated with bichromate of silver the glom-
erules strongly recall the appearance of the olfactory glomerule
figured by Retzius (92) for the vertebrates, and may perhaps be
very well called olfactory glomerule. But exactly what their
relations may be with the surrounding cells and the incoming
fibers I am not able to say definitely. In none of my prepara-
tions is an unbroken connection shown between them and the
cells clothing the lobes, the fragmentary appearances, however,
amply warrant the supposition that the processes of the cells
make their way between the bodies and after passing some dis-
tance in the middle mass of fibers send a branch into one of the
glomerulz and another one into the proto-cerebron (fig. 10, 16
and 24, Pl. XXI). Whether the process from a single cell sends
branches to more than one body does not appear, but if one
may judge from the form of the cells of the mushroom body,
probably it does not.

THE ROOT OF THE ANTENNO-SENSORY NERVE.

Besides the fibers just described there are to be distin-
guished two other kinds. One of these composes the root of
the antenno-sensory nerve, which in preparations with osmic
acid or by the copper-hematoxylin method may be traced from
its entrance into the lobe on the lower anterior surface nearly to
the posterior upper surface. Throughout its course it gives off

Kenyon, Zhe Brain of the Bee. 175

numerous fibers and branches. My preparations by the better
neural method that are favorable for tracing it are not numer-
ous. Fig. 16 represents one in which the fibers shown are all
that are impregnated in this region. Here a fiber is seen com-
ing in from the nerve and at some distance from its entrance
bending aside to a glomerula from which another fiber passes
out and then on towards the proto-cerebron. The other fiber
soon after entering breaks up into three branches one of which
terminates ina glomerula. The tuft-like termination was not
seen when the drawing was made, but after the latter was fixed
to the plate a re-examination of the specimen brought it to
light, but with scarcely sufficient distinctness to be drawn with
a camera.

If one is to credit, as one must, the long list of writers
since the time of Newport dealing with the antenne anatomi-
cally and physiologically, one must conclude that these organs
have at least two, and in many cases, if not always, three differ-
ent functions. That they are both tactile and olfactory has
long been known, and recently Child (94) has brought forth
very good anatomical reasons for their being also auditory.
Such being the case one might expect to find as many different
kinds of terminations in the antennal morula.

There is a striking resemblance between the tufts forming
the glomerule and those forming the olfactory glomerulz in
mammals as described and figured by Retzius ( 92 @); and, since
in the ventro-cerebron where sensory fibers from the oral nerves
undoubtedly terminate no such glomerule are found, one may
be very easily led to the conclusion that the glomerule are for
olfactory terminations. But Iam unable to produce evidence
of other terminations and must for the present conclude that
the glomerulze are formed by the terminations of all kinds of
fibers from the antennze. This conclusion is supported by the
fact that the tubercles of the central body, in which fibers from
the ocellar nerves apparently terminate, and the ocellar glome-
rule have a very similar appearance.

Another kind of fiber is shown along with its cell in fig.
15. This was found in the posterior ventral regions and bears

176 JouRNAL OF COMPARATIVE NEUROLOGY.

a slight resemblance to cells and fibers that are undoubtedly of
efferent nature. It may bea portion of such a one that by
branching among the olfactory glomerule as indicated in the
figure makes a reflex course from the afferent antennal fibers to
the antennal muscles. Still it may be only an association fiber
of which there may be many in the antennal lobe, though their
appearance does not distinguish them as such as readily as in
the case of the association fibers of the rest of the brain.
_ Whatever other fibers there are that might be classed as such
are of small size. Some of them appear to pass into the neck
already spoken of as connecting the lobe to the rest of the
brain.

THE ROOT OF THE ANTENNO-MOTOR NERVES.

The small internal antenno-motor nerve supplying the an-
tennal muscles within the head appears to be but a branch of
the larger one passing on to the antenna and with it has a com-
mon root. In sagittal sections treated by ordinary methods
this may be readily followed on the lower side of the antennal
lobe and somewhat to one side of its median line as a bundle of
medullated fibers that passes through the group of cells filling
the lower space between the cesophageal commissure and the
globular mass of fibrillar substance of the lobe. It penetrates
the fibrillar substance here and may still be followed through an
inward, backward, and upward course for a considerable dis-
tance. Gradually it decreases somewhat in size or loses its
fibers, and is finally untraceable. In such sections of brains
impregnated with bichromate of silver the fibers are frequently
found impregnated and then form a large bunch of branching
fibers spreading out in the commissure taking in the trito-cere-
bron and to a slight extent the ventro-cerebron. Branches also
pass upwards into the proto-cerebral region. In one case of a
thick frontal section embracing the posterior part of the anten-
nal lobe and nearly all of the proto-cerebron behind its plane a
single fiber considerably smaller for a portion of its length can
be seen above the level of the lobe, as shown in Plate XVII on
the right where an attempt was made to reproduce it. Below

Kenyon, Zhe Brain of the Bee. 177

it decreases in size and joins several other fibers, the whole of
which were not impregnated, and forms with them a band of
fibers traceable down behind the lobe until hidden by the inter-
vening strongly impregnated glomerule. As this band occu-
pies the same position as the antenno-motor root seen in ordi-
nary preparations I take it for granted that the fiber is motor
and belongs to this nerve. The large part of the fiber inclines
posteriorly in passing upward, terminating, so far as traceable,
very close to the inner root of the mushroom body at some little
distance from the median line. Three of its branches are im-
pregnated. The lower one passes forwards towards the inner
side of the antennal lobe and does not subdivide. From this
fact and its apparent destination I have supposed that its cell of
origin is situated among the cells filling this space between the
lobe and the commissure. Higher up two branches are given
off nearly together, one passing internally towards the median
line, and the other, which is much longer, passing outward and
downward in the trito-cerebral region and branching. But here
it is obscured by other details. A short distance above this an-
other long branch is given off. This goes diagonally backwards to
the posterior-lateral angle of the proto-cerebron ending in several
small branches.

In other sections made in the horizontal plane fibers of a
similar appearance were found taking a horizontal course and
passing apparently beneath the antennal morula (Pl. XIX).
These branch, as shown in the diagram, much more profusely
than the other one just described, a fact that is doubtless due to
their better impregnation. One sends a long slender process,
or rather continues as such, backwards to the layer of cells
clothing this part of the brain. But whether it actually arises
from any of them I am unable to say. It is not impossible, and,
if one considers the fiber shown on the opposite side of the
plate, which after branching profusely and irregularly sends off
a slender process in the direction of the antenno-motor nerve,
it may not seem improbable. The details are not sufficient to
settle the matter, however, and until they are shown to exist, I
shall be inclined to believe that probably all the cells giving rise

178 JOURNAL OF COMPARATIVE NEUROLOGY.

to the antenno-motor nerve are situated close to or in the lobe
on the anterior side of the brain. Fig. 39 represents a camera
drawing of the two fibers just described and also another from
the next section above them.

The Dorso-Cerebral Fiber Tracts.
THE CONNECTIONS WITH THE OPTIC LOBES.

Tracts of fibers passing from the optic lobes into the cen-

tral part of the proto-cerebron were early recognized by Ber-
“ger (78) and Bellonci (s2), but the interpretations of these au-
thors are very largely incorrect. Viallanes (7,88) seems to
have described most of them much more correctly, and the
same may be said of Cuccati (sg), so far as I am able, without
an actual study of sections of Somomya, to homologize his results
with my own. Certain peculiarities are figured and described
by him that render a comparison difficult. '

Before describing the connections it should be noted that
the masses of fibrillar substance forming what are usually known
as the optic ganglia, but which are much more properly denom-
inated fibrillar masses, are seen in frontal or horizontal sections
treated by ordinary methods to be composed of two outer lay-
ers of densely staining masses, and very much resemble in form
two meniscus lenses placed one within the other. The space
between them is filled with a loose mass of fibers, and the whole
is so placed as to have its convex surface directed outward and
its concave surface inward.

The inner of these masses lies in hexapods close against
the central proto-cerebron, being separated from it by a layer
of cells and a few bands of fibers. In other words there is no
optic nerve such as is found in the Crustacea. The attempts
by the earlier writers to distinguish an optic nerve were long
ago shown by Viallanes (87) to be more or less unsuccessful,
since there is not one but several connecting tracts. These
with the optic lobe sufficiently removed from the rest of the
brain, might, however, produce the homologue of the crustacean
optic nerve.

Kenyon, Zhe Brain of the Bee. 179
The Anterior Optic Tract.

Even in ordinary preparations there are indications of fibers
passing radially or nearly perpendicularly to its two surfaces,
through the inner fibrillar mass. Emerging from the inner sur-
face these are gathered into two bundles, the larger of which
passes forward, and slightly downward along the outer surface
of the central proto-cerebron and finally terminates in a small
oval body called by Viallanes (7) the optic tubercle, situated
immediately above the antennal lobe and to one side and below
the terminus of the anterior root of the mushroom bodies of
that side. In preparations with bichromate of silver the bundle
is often very prominently shown, and in addition also the arbor-
escent terminations of its fibers in the optic body, as shown in
the diagrams that follow. This body in the bee is divided into
a large inner mass and a very small outer mass, and into the
latter some of the fibers of the tract send each a small branch
before passing on to the larger body.

Other fibers apparently arising from cells in the immediate
neighborhood also branch in the body and connect it with other
parts of the brain. One group passes to the opposite side and
appears to terminate in the opposite optic body. Others pass
backward, but no tracts appear to connect it with the mush-
room bodies, although individual fibers are often found going
in that direction.

The Postero-superior Optic Tract.

As just indicated, the fibers emerging from the convex sur-
face of the inner fibrillar mass divide into a large anda small
bundle. The latter may be considered the postero-superior
optic tract, which seems to have escaped the notice of Viallanes
(87,88). It may be easily traced in preparations either by the
copper-hematoxylin method or by the _ platino-osmo-aceto-
picric acid method of von Rath, and after leaving its larger
companion, which is almost immediately, it passes upward along
the outer surface of the central proto-cerebral mass, and joining
the antero-superior tract, to be described a few lines further on,
takes an inward course until, arrived close to the stalk of the

180 JoURNAL OF COMPARATIVE NEUROLOGY.

outer mushroom body, it leaves this other tract and passes be-
hind the stalk close to the junction of the latter with the calyx.
Whether any of its branches pass into the calyx here I am not
able to say definitely, but apparently they do. In preparations
with bichromate of silver some at least of its fibers may be fol-
lowed across the intervening space to the opposite side of the
stalk of the inner mushroom body. Whether any of them con-
tinue on into the superior commissural tract my preparations
thus far made do not show.

The Antero-supertor Optic Tract.

This as described by Viallanes (§7) and Cuccati (gg) starts
from the outer fibrillar mass. Instead of originating like the
two tracts just described from the radiating fibers of the mass,
it arises from the fibers filling the space between its two lentic-
ular portions. These fibers are gathered into a bundle and leave
the mass at its antero-superior edge. Passing backward and
inward through the intervening layer of cells, the bundle reaches
the outer surface of the central proto-cerebral mass, then turning
upward joins the postero-superior bundle. Just before reaching
the stalk of the outer mushroom body it leaves its companion
and passes in front of the stalk, close to its junction with the
calyx, to the space between the two stalks where its fibers branch,
one group passing into the outer, the other into the inner
calyx. In one preparation I was able to determine the cells of
origin of this tract and to follow it through several sections to
its connection with the optic mass. According to the facts
shown in this brain impregnated with bichromate of silver the
description should be reversed and the union of the tract with
the optic mass be spoken of as its terminus, for the cells from
which it originates comprise a small group on the supero-ante-
rior-lateral surface of the central proto-cerebral mass and send
their processes as a bundle of fibers almost directly backward
to the space between the two stalks, whence a branch passes
into the calices and another to the fibrillar optic mass, as
described.

Kenyon, Zhe Brain of the Bee. 181

The Antero-postertor Optic Tract.

This has been well described by Viallanes (§7) in his me-
moirs on the hexapod brain and also by Cuccati (gg) in his
paper on Somomya erythrocephala. Like the tract last described
it is formed from the fibers coming from the central portion of
the outer optic fibrillar mass, which it leaves at the same point.
Leaving the antero-superior tract at the optic mass it takes a
backward and somewhat inward and downward course through
the intervening mass of cells, passing over the anterior optic
tract and between the inner optic mass and the central portion
of the proto-cerebron and turns into the latter at its postero-
lateral lower angle. After entering here the fibers separate
from one another and branch, but may be followed for some
distance towards the median line. Where its cells of origin are
to be found I cannot say definitely. But in certain of my _ bi-
chromate of silver preparations I have seen processes from cells
in a group near the starting point of the tract entering the
fibrillar mass, and it is not improbable that they are the cells of
origin of the fibers of this tract.

The Posterior Optic Tracts.*

Of the remaining tracts connecting the optic lobe with the
central proto-cerebral mass, there are several; but before pro-

*The following shows to what extent my results correspond with those of
Viallanes (87) who found four and I five tracts connecting the optic lobe with
the central cerebral mass:

A. Connections with the outer optic mass.
I. Faisceau supéro-antereur =
Antero-superior tract mzh#.

2. Faisceau supéro-postereur =

&

Antero-posterior optic tract mzhz ,

B. Connections with the inner optic mass.

3. Faisceau inféro-antereur =
Anterior optic tract mhz.
4. Faisceau inféro-postéreur, 2 tracts =
2 of my posterior tracts.

In his work on the grasshopper (88) he was unable to find the two tracts
from the outer mass, while from the inner mass he found arising two tracts»
one corresponding to my anterior optic tract, the other—his cordon commis-
sural—to my lower optic commissure.

182 JOURNAL OF COMPARATIVE NEUROLOGY.

ceeding with their description it should be noted that the inner
optic mass is so turned as to bring its posterior edge much closer
to the central brain mass than its anterior margin. It is at this
posterior margin that the entrance to the space between its two
lenticular portions is situated.

From this opening emerge a large number of fibers gath-
ered into several bundles, the most of which terminate in the
adjacent posterior lower portion of the central proto-cerebron.

' Of these bundles Viallanes (7) distinguished four, and
Cuccati (gg) seems to have found some of them in Somomya.
' The inner optic region of this genus, as shown by the latter
author, differs so much from what I find in the bee or have seen
figured or described elsewhere that comparisons are very uncer-
tain. What he calls the ovoid body (eiformige Korper) doubt-
less corresponds to the inner optic mass as generally met with,
but what may be the homologue of his S-form body I am ata
loss to know unless it may possibly be the outer lenticular por-
tion considerably separated from the inner one. But in case
that were true, there would be an anomalous condition of fibers
from the concave face of the outer optic mass passing through
the space, a condition of affairs that is not true in the case of
the bee nor probably in any other hexapod. He also figures
and describes several tracts of fibers that apparently correspond
to some of those to be described here a few lines ahead, but as
originating from the outer surface of the S-form or of the ovoid
body, which, I take it, is equivalent to describing them in the
bee as arising from the outer surface of the inner optic mass,
and this is not true. ;

But to proceed with the optic tracts, there may first be
described one, noted by both Viallanes (g7) and Cuccati (gs ),
leaving the inner margin of the inner lenticular body and pass-
ing into the central proto-cerebral mass a little above the point
of entrance of the antero-posterior tract and continuing thence
as a loose band of fibers across the posterior region of the
brain and below the fibrillar arch to the inner optic mass of the
opposite side, thus forming what may be termed the upper
optic commissure. It does not pass directly across but is

Kenyon, Zhe Brain of the Bee. 183

arched slightly upward. It may be followed with little difficul-
ty in ordinary preparations, and I have several times found its
fibers impregnated in brains treated by the bichromate of silver
method, Whether its fibers branch in the central brain I can-
not say definitely. There are indications, however, that they
do, and further, that their cells of origin may be situated among
those forming the mass of cells behind the central body.

Below this, in a plane taking in the anterior optic tracts
and the optic body, and a little below the lower level of the in-
ner roots of the mushroom bodies, there are three tracts, which
may be seen in figure 10, Pl. XVI. These differ considerably
according to the direction of the plane in which the section is
‘cut, and also seem to differ somewhat in different individuals. In
another brain from that from which the figure was taken there is
a bundle that is not shown in the figure. This is described by
Viallanes (7) as divided into a thicker and a thinner bundle,
which is the case here. Both emerge from the inner edge of
the inner lenticular body and terminate in the neighboring cen-
tral region after penetrating no further than do the posterior two
of those shown in the figure. The anterior of the two is con-
siderably the larger and from its manner of staining may readi-
ly be considered as composed of many very fine fibrils. The
other is composed of fewer and coarser fibers and seems to
arise more directly from the space between the two lenticular
bodies.

Below these are two more bundles, or the posterior two
shown in the figure. These resemble the one just described
and arise and terminate similarly.

At a slightly lower level is the last of the series, which
arises from near the margin of the inner lenticular body and
passing directly into the central mass, bends slightly down-
ward and then upward again to its former level and passes
on as the lower optic commissure to the lobe of the opposite
side. This is a much more compact and well marked bundle
than the upper optic commissure and seemingly gives off no
branches, although further study will probably show that it
does. In one preparation by the copper-hematoxylin

184 JOURNAL OF COMPARATIVE NEUROLOGY.

method in which the sections-are in the horizontal plane I find
fibers above it on each side of the brain that seem to run
down to and join itin its middle portion. But in bichromate of
silver preparations, although I have several times found some of
its fibers impregnated I have not found sufficient evidence to
warrant my saying that it branches. Just where its cells of or-
igin are I have not been able to determine.

THE DORSO-CEREBRAL COMMISSURES.

Of the bands of fibers connecting the two lateral halves of
the dorso-cerebron there are at least six, and of these two have
already been noted in connection with the optic tracts. Some
of them have long been known, but on account mostly of a
lack of proper neurological methods have seldom been correctly
understood. Viallanes (g7,88) seems to have made fewer, mis-
takes than any other writer who has considered them.

The Superior Dorso-cerebral Commissure.

This band of fibers crossing the median line of the brain
above the central body and between the two inner stalks of the
mushroom bodies (fig. 2) was noted by Dietl (76) and Ber-
ger (78) and considered as connecting the two optic lobes, a
mistake perpetuated by Bellonci in his study of Grylotalpa.
The fibers are brought out very prominently by most of the or-
dinary methods and I have repeatedly found them impregnated
in brains treated by the bichromate of silver method. They
are all of small size and non-medullated. By a comparison of
frontal and horizontal sections (figs. 2 and 7) they are seen. to
form a band whose broadest extent is in the antero-posterior di-
rection, and to be divided at either end into two parts—a divis-
ion that can sometimes be distinguished throughout the length
of the commissure—one of which passes behind and the other
in front of the stalk. There does not seem to be a crossing of
the fibers, but those passing in front of one stalk also pass in
front of the other. In preparations with haematoxylin or
with osmic acid the halves may be traced in horizontal sections
around the inner stalks to the space between these and the outer
ones and apparently into the calices. Since the tracts from the

Kenyon, Zhe Brain of the Bee. 185

optic and antennal lobes also enter this region, very much care
is necessary in distinguishing the different tracts, but since they
fuse to some extent upon entering the calices, it is impossible to
follow any one of them singly. Viallanes probably correctly
interpreted this bundle as a commissure between the two pairs
of mushroom bodies. There is apparently very little probabil-
ity of any of its fibers reaching the optic lobes, though none of
the methods employed by me have thus far demonstrated con-
clusively. that they do not, nor have I been able to determine
their exact terminations in the calices nor the location of their
cells of origin. In preparations with hematoxylin and with
osmic acid processes from the cells behind the inner side of the
inner stalks have been traced upwards and forwards, apparently
passing into the commissure as it passes around the stalks, but
no such fibers have been found impregnated in brains prepared
according to the bichromate of silver method. This negative
evidence is not, however, at al! conclusive since a sufficiently
large number of brains have not been treated.

The Anterior Commissure:

The smal] band of fibers composing this commissure was
first discovered by Viallanes (87) as connecting the two optic
bodies. It may be followed in ordinary preparations without
much difficulty from the posterior margin of one optic body
across the anterior region of the brain and below the roots of the
mushroom bodies to the optic body of the opposite side. Ap-
parently its fibers originate from the group of cells immediately
inside of and below the body. The processes from the cells
seem to pass upward, and after sending a short process into the
body where as seen in bichromate of silver preparations, it
branches very profusely, and then passes across the median line.
I have not been able to determine exactly its termination on the
opposite side or whether it or any of its branches penetrate the
optic body here. One bichromate of silver preparation where
the fibers of the tract are most completely impregnated is incon-
clusive from the very fact of the extent of the impregnation.
From it one might conclude that branches pass into the optic

186 JourNnaL OF CoMPARATIVE NEUROLOGY.

body, but the greater number into the region immediately
behind it.
The Optic Commussures.

The two tracts of fibers forming the one the upper and the
other the lower optic commissure have already been described
in connection with the optic tracts. As noted there, I am un-
able to say definitely whether either give off branches to the
brain in passing, and it may be added here that I have no evi-
dence to show that a single nerve cell makes the entire con-
nection between the lobes, if such be actually the function of
the tracts. The question needs much further study.

The Inferior Dorso-cerebral Commissures.

The two groups of fibers connecting the lateral halves of
the dorso-cerebron immediately above the cesophageal fora-
men have been variously misunderstood. They are shown in
fig. 10 where they appear as two short tracts in front of the
larger lower optic commissure. The anterior of the two was
supposed by the earlier writers to connect-the antennal lobes,
and even the olfactory glomerulz of one side with those of the
other. Of such a direct connection I find no evidence what-
ever, though without doubt the two commissures may be con-
sidered as connecting the two deuto-cerebral lobes. In ordinary
preparations sectioned in the horizontal plane both commissures
are found immediately above the foramen, in fact almost bord-
ering upon it, and may be traced for a short distance into the
fibrillar substance of either side where the fibers curve slightly
downward and separating from the tract branch and disappear.
In frontal sections the fibers may be followed a little farther
than in those cut in a horizontal plane. In fig. 5 one of the
tracts may be seen though somewhat indistinctly.

In bichromate of silver preparations, although I have fre-
quently found commissural fibers impregnated, I have not found
sufficient details to warrant a definite assertion as to the exact
relation of the tracts to the rest of the brain, nor as to the situ-
ation of the cells giving rise to their fibers. What details there
are, however, indicate that the anterior tract connects the two

Kenyon, Zhe Brain of the Bee. 187

regions, which may be called deuto-cerebral, immediately be-
hind the antennal lobes. If it in any way connects the two
lobes or their glomerulz, it is only by means of intervening as-
sociation fibers. But such a connection is doubtful from phy-
siological reasons. It seems much more probable that the com-
missural fibers by the aid of association fibers of one side,
should connect the glomerulz of that side with motor fibers of
the other. Still the other supposition is not impossible, and
one should rather follow the maxim of Hunter, ‘‘do not think,
but go and see’, and wait until facts, physiological or other-
wise, are obtained to decide the matter.

The fibers of the posterior tract, which is separated from
the other by the ascending tracts from the antennal lobes to
the mushroom bodies, connect more posterior parts of the brain.
The fibers shown in fig. 38, apparently belong to this tract
since at the median line they occupy the same position. Here
they are obscured by a mass of precipitate filling the roof of
the foramen, but since there are no other fibers impregnated here,
there can be little doubt that the fibers of the opposite side are
a continuation of them. The branching and larger portion of
them is found in the posterior lateral lower angle of the brain,
and it is possible that they may originate from cells in this
neighborhood. One of them, it may be noted, sends a slender
branch forwards toward the antennal lobe.

THE ANTENNO-CEREBRAL TRACTS.

The existence of tracts of fibers passing upwards from the
antennal lobes into the proto-cerebron has been known ever
since Bellonci (gg) published his account of them in Gryllotalpa.
But of the three pairs of such tracts he seems to -have distin-
guished but two, and certainly misunderstood the relationships
of these. For he describes them as antenno-optic connections
passing from the antennal lobe upwards into the proto-cerebron
and to the optic lobes by way of the superior commissure, which
he recognized with Dietl and Berger as connecting the optic
lobes. The same error was committed by Cuccati (8s) who
found in Somomya what is unquestionably the homologue of

188 JOURNAL OF COMPARATIVE NEUROLOGY.

the inner tract to be described a little farther on, and which is
also the main tract discovered by Bellonci. Viallanes (87)
found the tract in the wasp and for the first time described it
correctly.

In certain of my preparations of the brain of the bee by
the copper-hematoxylin method these antenno-cerebral tracts
are very distinct and very easily followed. This is the case in
sections cut in any o¢ the three planes.

The Inner Antenno-cercbral Tract.

_ The one first to be described is the largest and also the one
first discovered. It arises in the neck of fibrillar substance con-
necting the antennal morula with the rest of the brain and as-
cending upwards, inwards and backwards (fig. 2) it passes be-
tween the two ventral commissures of the dorso-cerebron (fig.
10). Thence curving backwards somewhat it passes behind the
root of the mushroom bodies and the outer hinder margin of
the central body and in front of the fibrillar arch (figs. 8 and g)
to the level of the superior commissure, behind which it may
be seen in section in fig. 7, From here it bends forward and
passing around in front of the inner stalk of the mushroom
body enters the inner calyx at its junction with the stalk and on
the antero-lateral side of the latter.

In bichromate of silver preparations I have several times
found the fibers of the tract impregnated for nearly their entire
length. And in many cases different portions of the tract in
successive sections were so well impregnated that their superim-
position was a very easy matter. Fig. 24 represents the super-
imposition of three such sections and shows the tract from
the calyx above to the inside of the antennal morula below. In
no case have I found fibers from a glomerula passing into the
tract, but the arrangement of the many fiber-fragments that
have been seen almost conclusively demonstrated that they enter
it (fig. 24). The fiber from the glomerula shown in the figure
offers avery good example.

Nor have I found the fibers in cennection with cells, but,
considering their connection with the glomerulz as_ practically

Kenyon, Zhe Brain of the Bee. 189

demonstrated, it may be remembered that very good reasons
appear for considering the glomerulz as connected with the cells
clothing the morula, and from this it is fairly evident that the
same cells give rise to the fibers of the tract. Ai little further
evidence will appear in connection with the outer tract.

The Middle Antenno-cerebral Tract.

The next tract to be considered is the smallest of the three
and arises as a branch of the one just described at a point just
above the level of the ventral commissures. It takes an out-
ward course behind the mushroom body (fig. 6) and continues
upward to the region behind and between the stalks and then
bending forward somewhat passes into the outer calyx.

This seems to be the branch figured by Bellonci as passing
outward into the supposed tract between the optic lobes. In
several of my bichromate of silver preparations it is very read-
ily followed.

The Outer Antenno-cerebral Tract.

This tract is of considerable size and originates, as shown
in bichromate of silver preparations (fig. 24), from cells above
the antennal morula. From the morula it passes backward and
outward towards the side of the central brain mass and gradu-
ally turning upwards passes behind, but in contact with, the low-
er optic commissure (fig. 6) and finally reaches the outer dorsal
surface of the fibrillar substance and there, joining the antero-su-
perior optic tract, passes in front of the outer stalk into the
calyx above. Whether any of its fibers continue to the other
calyx or not, I cannot say.

In some frontal sections there appears to be given off from
this tract below the lower optic commissure a small bundle of
fibers that curves outward and apparently joins the commissure.
But in horizontal sections it seems to follow the commissure to
a point near the outer surface of the fibrillar substance, where it
turns abruptly forward and enters the mass forming the antero-
lateral lower angle of the central cerebral mass.

190 JOURNAL OF COMPARATIVE NEUROLOGY.

THE DORSO-VENTRAL TRACT.

Five tracts of fibers have thus far been described as enter-
ing the calices of the mushroom bodies and there still remains
another. This was first brought to my notice in a frontal sec-
tion of a brain impregnated with bichromate of silver, and was
subsequently recognized in a similar section of a pupal brain
treated by the copper-hematoxylin method. It begins as a
small band of fibers in the region between the two stalks, where
branches of it enter both calices, and passes downward be-
neath the cells clothing the posterior surface of the brain to the
cesophageal foramen, then continues anteriorly along the roof of
this so as to reach the opposite side of the brain near the anterior
surface. In its passage along the roof of the foramen its fibers
send branches into the side from which the main fibers came, and
these form an arborescent termination among branches of fibers
coming from the ventro-cerebron and the ventral cord. Since
these latter fibers cross the median line above the foramen an-
teriorly, the passage of the tract to the opposite side brings it
into close relation with them along their whole extent along the
roof of the foramen. This relation is best shown in plate XX,
which shows two fibers of the tract as seen in a single section.
The cells of origin of the tract have not been seen. But suff-
cient has been determined to show in what close relationship the
cells of the mushroom bodies stand with the ventral nervous
system.

The Ocellar Nerves.

In the bee the ocelli are situated close together, andas a
consequence their so-called ganglia are contiguous and their
nerves toa large extent fused. The nerve from the median ocel-
lus passes downward and backward between the two inner calices
and fusing with the nerves from the lateral ocelli forms with them
a single mass that divides to pass around a large trachea piercing
the brain in the median line between the calyx cups. Immedi-
ately below this the fibers again come into close contact, but at
a little lower level some of those coming originally from the
median ocellus separate from the rest and follow a course that

Kenyon, Zhe Brain of the Bee. IgI

takes them down in front of the fibrillar arch to terminate final-
ly, as apparently shown in copper-hzematoxylin preparations
cut sagittally, in the tubercles of the central body.

The others form a broad band of fibers passing down be-
hind the fibrillar arch to which, as suggested by Cuccati (gs),
some of them may give off branches. Certainly some of the
smaller fibers cannot be traced below this level (Pl. XVI).

Both the anterior and the posterior groups are composed of
two kinds of fibers, one enormously large and the other of or-
dinary size. The large fibers are very noticeable in prepara-
tions by the copper-hematoxylin method from the fact that
they stain but slightly and thus appear as light colored spots in
a deeply colored surrounding mass of cells (fig. 7-9). Similar
results are obtained with von Rath’s platino-osmo-aceto-picric acid
mixture. The unstained fibers look very much like sections of
tubes. But in preparations treated with Weigert’s hematoxylin,
or in those after-stained with fuchsin the fibers stain more or less
deeply and thus demonstrate that they are at least not empty
tubes. Even in preparations by my copper-hematoxylin method
staining sometimes takes place. In such cases the inner mass
appears in section to be shrunken away from the surrounding
fibrillar wall, but remaining connected with it by slender fila-
ments. This would seem to show that they are not formed
upon exactly the same plan as other nerve fibers. A careful
histological study of their structure is necessary.

The nerves thus constituted may be followed for some dis-
tance below the fibrillar arch, but seem to branch and gradually
decrease in size. This is noticeable in the figures, where in
fig. 7, the anterior nerve appears with three large fibers and at
a considerably lower level (fig. g) there is but one. The fibers
of this nerve soon become untraceable and appear to pass into
the fibrillar arch and the ocellar glomerule beneath.

Some of the fibers of the other two nerves seem to termi-
nate in the same way, but a large number of the larger fibers
continue downward, as seen in both horizontal and frontal sec-
tions, until they reach the neighborhood above the cesophageal
foramen, where they separate. Some seem to terminate in this

192 JoURNAL OF COMPARATIVE NEUROLOGY.

region. The others come into close contact with the hinder
surface of the brain and pass on downward in the upper sur-
face of the cesophageal commissures to the ventro-cerebron,
whence they pass on backward along the dorsal surface of the
ventral cord, thus effectually disproving Binet’s (94) assertion
that there are no large fibers in the dorsal region of the cord
comparable to those found in crustacea. In many cases I have
found these large fibers of the cord in bichromate of silver
| preparations passing along the dorsal surface of the ventro-
cerebron on into the region just below the level of the central
body as shown in Pl. XX. What their significance may be I
do not at present undertake to say. Had Binet persevered
longer in his trial of either of the two methods preeminent in
the study of the nervous system, he probably would have found
them.. But while the existence of the large fibers is beyond
question, there is still a chance that my description of them as
coming from the ocelli is erroneous, for the reason that I have
not been able, in specimens prepared by the bichromate of silver
method or by any other, to follow a fiber through an unbroken or
unsectioned course from the ocellar ganglion or the upper por-
tion of an ocellar nerve to the ventral cord. Yet impregnated
fibers have been followed without interruption from the copper-
the level indicated above, and A the large fibers have been care-
fully traced through sections treated according to my’ copper-
hematoxylin method. It should be noted that Cuccati (8s)
also traced them in Samomya, as I have done here, into the
ventral cord. Viallanes (87,88) did not succeed in following
them below the fibrillar mass behind the inner root of the
mushroom bodies.

THE FIBERS FROM THE BRAIN TO THE OCELLAR GANGLIA.

Besides the fibers just described as constituting ‘the ocellar
nerves there may, in preparations by the bichromate of silver
method, be distinguished others of an efferent nature (fig. 42,
Pl. XXII). These may be traced from below the level of the
calices into the ocellar ganglia where they branch arborescently.
None are large. Where they originate or what may be their

Kenyon, Zhe Lrain of the Bee. 193

fibrillar connections within the brain, I have not as yet been
able to learn. Not many preparations were obtained show-
ing them passing out of the ganglia, and in fact only one in
which they could be traced from below the calices, and from
this the two fibers of the figures were taken.

As there are no muscular structures in the ganglia, their
function is doubless to control the action of the pigment of the
pigment cells.

The Commissural and Ventro-cerebral Region.

Since in the case of the bee they are so closely bound to
it, the parts composing the cesophageal commissures may be
considered along with the ventro-cerebron.

As already pointed out, the trito-cerebral lobe is very much
reduced and is mainly distinguishable externally by the labral
nerve. This is not far behind the internal antenno-motor nerve
and its root may be traced for a short distance into a small lobe
just inside the neck of the antennal morula. Fig. 2 is just a
little too far forward to show it, but asection of the nerve may
be seen on the left at its point of entrance. In bichromate of
silver preparations the fibers entering from it very quickly form
a bushy tuft of branches just beneath the root of the antenno-
motor nerve. Some of these reach back into the ventro-
cerebron.

The roots of the other oral nerves may be followed in or-
dinary preparatious each as a light band of fibers that passes
upward above the point of entrance of the nerve and then bends
inward towards the median line and ends in a roll of fibers that
is apparently much more easily distinguishable in other forms
than in the bee, and which Binet (94) calls the ventral column.
This passes backward into the ventral cord. The two roots that
Binet describes for each crural and each ventro-cerebral nerve
in Cerambyx and other beetles I do not find in my sections of
the bee’s ventro-cerebron. This may be due to their being
fused, but the attention that I have given this portion of the
brain is as yet small in comparison to that given the dorso-
cerebron.

194 JouRNAL oF CoMPARATIVE NEUROLOGY.

In bichromate of silver preparations some of the fibers en-
tering from the nerves very quickly break up into branches, but
reach a little above the lower half of the ganglion. In a few
cases the roots were found impregnated for nearly their whole
extent and did not appear to give off many branches to the
ventral region. In one case two cells in front of the mandibu-
lar nerve were each found connected with a fiber that passed
out through the nerve, but whatever inner branches they may
have had were not impregnated (Pl. XX). In another case
‘a large cell was found on the lower lateral side of the brain
sending a process into the region above, where it gave off a very
extensive small branch (fig. 36). Near the broken end of the
fiber another that is not shown in the figure began. This was
apparéntly a continuation of it. The appearances of the sec-
tion indicated that the fiber had been cut on account of its form-
ing a slight bend outside the plane of the razor. The second
fiber turning forwards gradually became swollen distally and
then decreasing passed asa smaller fiber into the root of the
antenno-motor nerve. The latter cell then is certainly motor,
and taking for granted what has already been fairly well demon-
strated by other observers; namely, that cells in the brain send-
ing their neurites out of it are motor or bearers of efferent neu-
ral impulses, and the fibers entering from external cells are sen-
sory, it is just as surely true that the other cell is of a motor
nature.

This ventral position of motor cells here tends to indicate
that the dorsal motor and ventral sensory area of ventral gang-
lia, as distinguished by physiologal experiments, is considerably
independent of the position of the cell. It may be pointed out
that in dorsal lesions it is the connection of the dendrites of
motor cells with fibers bearing stimuli to them from other
parts of the nervous system that is broken; while in ventral le-
sions it may be the terminations of sensory fibers or of associ-
ation cells and their fibers or both that are destroyed. From
this it may be seen how indefinite are apt to be results obtained
by the physiological vivisection methods. Should experi-
ments be repeated with a thorough knowledge of the location

Kenyon, Zhe Brain of the Bee. 195

of the cells about a ganglion so as to render it possible to rup-
ture individual cells and not fibrillar connections, and sufficient
time is allowed to elapse for the degeneration of the dendrites
and neurite of the ruptured cell, it will doubtless be found that
ventral and lateral portions of the ganglion are motor.

Such careful experiments are needed and, performed upon
the ventro-cerebron, they may, by the aid of either the methy-
lin blue intra-vitam or the bichromate of silver method, be able
to demonstrate which of the large number of cells located there
perform the function of co-ordinating the movements of the
body.

The association fibers of this ventral region of the brain
are numerous, and of the many fragments of them seen one of
the best is shown in fig. 24. This, as is evident from the fig-
ure, occupies the upper portion of the commissural region and
sends the greater part of its branches and branchlets dorsally
into the lateral region of the proto-cerebron in the dorso-ventral
plane of the anterior root of the mushroom bodies. One branch
passes forward inside the inner antenno-cerebral tract.

Numerous fibers may be found connecting the antennal
morula through its neck of fibrillar substance with the com-
missure. A single fragment shown in plate XX (fiber 37) sends
a process upward in the posterior region that branches below
the level of the ocellar glomerulz, while another is sent forward
apparently to the antennal lobe. Just before reaching this it
sends a secondary branch downward into the ventro-cerebron.
The fibers seen entering the ventro-cerebron from the ventral
cord are in some cases remarkable for their size. These large
fibers occupy the dorsal region and have already been spoken
of in connection with the nerves of the ocelli. Fragments of
them have been seen as far back as the first thoracic ganglion,
and anteriorly, as before noted, they have been traced in bichro-
mate of silver preparations into the proto-cerebron behind the
ocellar glomerule. Branches are given off in this region that
pass among the glomerule to the commissural region as shown
in the plate. Much shorter ones are given off in the ventro-
cerebron. Another large fiber (fiber 38) apparently ends in the

196 JOURNAL OF COMPARATIVE NEUROLOGY.

ventro-cerebral and commissural region. Lower down in the
ventro-cerebron another fiber is shown (fiber 41) that branches
among the fibers from the oral nerves and thence apparently
passes backward into the ventral cord. A smaller fiber (40)
makes the same connections.

In some of my preparations there may be distinguished
what may be described as a roll of fine fibers, the individual
fibers of which cannot be traced, that passes through the ven-
tro-cerebron and thence upward through each commissure;
whence it crosses to the opposite lower side of the dorso-cere-
bron or over the anterior part of the roof of the cesophageal
foramen.’ I do not know what this can be unless it is a contin-
uation of the ventral column described by Binet (94). Its pas-
sage into the dorso-cerebron is directly contradictory of this au-
thor’s assertion that ‘‘ il n’existe dans le ganglion sous cesopha-
gien-aucun croisement des connectifs qui prennent leur origine
dans le cerveau.’”’ But Viallanes (87,88) speaks of a fibrillar
tract that passes from the cord to the opposite side of the dorso-
cerebron. In close connection with this roll individual fibers
may be followed from the cord to the same destination. .

What is apparently a branch of this roll continues upward
towards the central body in the commissure of the same side,
or without crossing the median line.

It is this roll of fibers that has already been mentioned in
connection with the dorso-ventral tract, with the fibers of which
it seems to come into contact. Assuming that, which is doubt-
less true, it is the continuation of the ventral columns described |
by Binet (94) and that the root of the crural and the alary
nerves terminating in it are sensory, which is also probably
true, there is then seen to be a direct sensory tract for external
stimuli from all parts of the body to the calices of the mush-
room bodies, a fact of no little importance in completing the
chain of evidence demonstrating that the cells of these bodies
are the ones that enable the animal to adapt itself to the vary-
ing conditions of life.

A similar group of fibers may be followed in copper-hama-
toxylin preparations from the ventral cord through the ventro-

Kenyon, Zhe Brain of the Bee. 197

cerebron to the antennal lobe within the region of the inner ter-
minations of the motor-fibers to the oral and ventral nerves.
In such preparations fibers leaving the tract may be. readily seen
and it is not a connection between the antenno-motor nerves
and the ventral cord such as Cuccati (s8) seems to imply in his
description of the same tract in Somomya. Connecting the
pair of tracts in the ventro-cerebral region are four transverse
bands of fibers. These have been noted several times in bi-
chromate of silver preparations, but the longitudinal tracts to
the antennal lobe were found impregnated but once.

The transverse cesophageal commissure seems to have be-
come completely fused with the ventro-cerebron in the bee, and
is apparently represented by a few transverse fibers found in the
lower floor of the cesophageal foramen.

The Cell Groups.

Having finished the description, incomplete though it be,
of the central fibrillar substance of the bee brain, there still re-
main the groups of cells clothing the mass to be discussed.
The location of these, after recognizing the general form of a
hexapod nerve cell, is of little physiological importance com-
pared with the extent and connections of their fibers, but mor-
phologically they may have considerable significance.

As before mentioned, the cells of the brain are gathered
into masses that completely cover the fibrillar substance in cer-
tain regions and fill in the spaces between its lobes. Thus the
spaces between the optic lobes, the antennal morula and the
central cerebral mass are completely filled by them, as is also
the deep furrow between the two lateral proto-cerebral lobes
on the posterior side of the brain.

These masses are, with certain exceptions, subdivided into
small groups the fibers of which form a bundle in penetrating
the central mass. These groups so far as I have been able to
distinguish them may be designated by numbers as follows be-
low. The most prominent of the exceptions to the rule of the
formation of small bundles are the cells about the calices of the
mushroom bodies. These are very similar in appearance to the

198 JOURNAL OF COMPARATIVE NEUROLOGY.

small cells filling the central portion of the calyx-cups and their
general mass is in some places continuous with that filling the
latter, their relation to which may be compared to the over-
flowing contents of a cup. They are found in the space be-
tween each pair of calices and in that between the latter and the
fibrillar mass below, anteriorly and posteriorly, and grade into the
mass of cells between the central mass and the fibrillar masses
of the optic lobes. No processes from any of them to the por-
tion of the brain beneath them have been seen in any of my
preparations, but in all they seem to be in some way closely re-
lated to the calices. In one instance a process was traced into
a calyx from a cell in the space between the pair of cups, and
this, branching there, exactly resembled the dendrites of the cells
inside. Since this was one of the earlier of my discoveries, and
since the boundaries of the cup are not always distinct in non-
stained, or bichromate of silver preparations, and since at this
moment I am unable to verify the matter, there is here a possi-
bility of a mistake. If not, and the cells are of the same order
as those inside the cup, their neurites must be looked for as
passing inside to the radiating bundles of fibers.

Between the posterior margins of the stalks and immedi-
ately below the calices I have several times found larger cells
impregnated, whose processes passed. in between the stalks and
up between the calices. Perhaps these may be the cells giving
rise to the fibers of the superior commissure, but the details to
be seen are too poor to warrant a conclusion.

THE CELLS OF THE DORSO-CEREBRON,

I. To proceed with the enumeration of the groups of
cells, there may first be noted a small group of medium sized
cells, situated dorso-antero-laterally beneath the outer calyx, the
processes of which pass almost directly backwards to the neigh-
borhood of the inner surface of the outer stalk and form the
processes giving rise to the fibers of the antero-superior optic
tract.

II. Behind and below these, but in close proximity, is an-
other group of similar appearance, the processes of which form

Kenyon, The Brain of the Bee. 199

a tract passing into the fibrillar substance towards the median
line of the brain.

III. Below the anterior optic tract nearly half way between
the inner optic mass and the optic body is a group of mod-
erately large cells, the tract of fibers from which passes under
the optic tract and upwards towards the middle superior surface
of the anterior root of the mushroom body, above which they
seem to branch. In all preparations where seen there is consid-
erable difficulty in distinguishing the fibers of this tract from the
outer branches of the tract from the posterior region of the
calices to the root.

IV. Immediately outside of and below the optic body is
a similar group whose processes pass beneath the optic tract
upward and inward, apparently, along the lower surface of the
anterior root.

V. Inside of and below the optic body is a group of cells
of median size whose fibers pass upward along the outer side of
the anterior root.

VI. Below these and above the antennal morula is a
group that, sends a tract of fibers upwards across the inner side
of the root (figs. 24 and 31, fiber 10 of the diagrams).

VII. Outside of these and above the morula are three
small groups that send as many tracts of fibers inward to the
central body (fiber 30). They pass below the latter structure
and, turning upwards in front of the tubercles of the central
body, enter the space separating its dorsal and ventral portions.
Apparently they form the tract that is figured by Bellonci (sg)
as connecting the inner antenno-cerebral tract with the superior
commissure on the opposite side of the brain, or as forming a
chiasma with its companion from the opposite side.

VIII. Near the latter group is another whose processes
form the outer antenno-cerebral tract (fig. 24).

IX. Beneath the calices and in the median plane is a
group of cells recognizable in fig. 1, the processes of which pass
directly downward, and according to Viallanes (gs) enter the
cesophageal commissure of the brain, thus forming a chiasma.
In the wasp (Viallanes 87) and in Somomya (Cuccati gg) their

200 JOURNAL OF COMPARATIVE NEUROLOGY.

relationships seem to be the same as in the bee, in which I find
no evidence of crossing.

X. Immediately behind the latter group is another com-
posed of cells of the same large size, the fibers of which pass
backward over the central body and connect it with the fibrillar
arch (fiber 2).

XI. Considering the posterior region of the brain there
may first be noted a small group situated below the outer calyx
at a point where the outer antenno-cerebral tract reaches the
. dorsal surface of the fibrillar substance. Its processes pass
downwards into conjunction with the tract and might be taken
for its processes of origin were it not for the fact that bichro- -
mate of silver preparations show that its cells are situated in the
antennal lobe. Where the fibers of this group go to I have not
been able to determine.

XII. Behind the stalks of the mushroom bodies is a small
group of large cells whose processes pass between the stalks to
the anterior root (fiber 7) giving rise to some of the association
fibers in that structure. ;

XIII. Behind the inner stalk there is a group of medium
sized cells whose processes pass inward behind the inner anten-
no-cerebral tract and behind the central body into which each
fiber sends several branches (fiber 5).

XIV. Behind the lateral margin of the central body and
beneath the fibrillar arch is a companion group whose fibers
pass directly forward and turning about in front of the inner
anteno-cerebral tract pass behind and send branches into the
central body (fiber 6). The two groups thus form a commis-
sure behind this structure. As before mentioned it is possible
that their neurites may be the fibers seen leaving the central
body and passing into the lower lateral portions of the proto-
cerebron and towards the commissural region (fig. 5).

XV. Above these groups and between the central body
and the fibrillar arch and below the latter is a small group
whose processes form a bundle (figs. 2, 5, 6, 8) passing just in-
side of the inner antenno-cerebral tract over the top of the

Kenyon, Zhe Brain of the Bee. 201

central body to the median anterior mass of fibrillar substance
(fiber 49). |

XVI. Above these and in front of the arch is a small
group of cells, often staining more deeply than those surround-
ing them, whose processes pass directly downwards outside of
the tract just described and appear to enter the inner antenno-
cerebral tract (fiber 3),

XVII. Above the ends of the fibrillar arch is a large
group of cells of large size whose fibers form a dorso-ventrally
flattened band that passes forwards outside of the inner antenno-
cerebral tract and above the superior commissure (figs. 2, 7, 8)
and bending about the inner stalk distribute themselves in the
fibrillar substance above and outside of the anterior root of the
mushroom bodies (fiber 23).

XVIII. Below the fibrillar arch and a little below the
commissure of the central body is a loose group of cells whose
processes in some cases appear to pass into the superior optic
commissure. In others they pass across to the fibrillar mass
behind the base of the junction of the roots and stalks of the
mushroom bodies (fiber 4).

XIX. Behind group XVI and separated from it by the
fibrillar arch is one that appears to send its processes down-
ward into the inner antenno-cerebral tract, but probably they
are sent into the central body.

XX. Another group below these and the fibrillar arch
sends its processes downward and inward apparently under the
superior optic commissure, in front of which they bend upwards
and apparently pass to the calices along with the fibers of the
superior commissure and those of the inner antenno-cerebral
tract.

XXI. The cells about the antennal morula are most nu-
merous in the space between it and the restof the brain, although
they cover almost its entire surface, and are perhaps gathered
into as many groups as there are inter-glomerular spaces. One
group that should have been noted before is situated in the in-
ner superior side of the neck of the morula and sends its fibers
upward through the anterior portion of the central mass of

202 JOURNAL OF COMPARATIVE NEUROLOGY.

fibrillar substance and near the median line. Near the lower
surface of the inner calyx they turn outward over the anterior
root.

XXII. Three groups that may be considered as one on
account of their situation below the neck of the morula have
their processes directed upwards toward the neck.

XXIII. In the lateral lower side of the central cerebral
mass are several groups. One large one at the posterior lower
edge of the inner optic mass sends its processes straight forward
into the fibrillar mass forming the anterior lateral angle of the
brain below the anterior optic tract.

XXIV. Another group inside the last sends its fibers into
the adjacent posterior angle.

XXV._ A little above the group just noted is another that
sends its fibers in among the terminations of the posterior optic
tracts.

THE CELLS OF THE VENTRO-CEREBRON,

Excepting the dorsal surface the whole of the ventro-cere-
bron is covered with a mass of cells all of which are of consid-
erable size, but largest ventrally. Among them may be distin-
guished seven principal groups.

XXVI. A ventro-median group between the origin of
the maxillary nerves sends a band of fibers directly through the
mass above, passing behind a group of commissural fibers
among which may be those of the transverse cesophageal com-
missure to the dorsal surface. E

XXVII. A second ventro-median group also occurs be-
tween the origins of the labial nerves. Its fibers after reaching
the neighborhood of the dorsal surface separate and apparently
reach the latter.

XXVIII. Between this group and the origin of the nerve
is another of large cells whose processes form a distinct tract
passing upward and outward just outside of the ventral column
at the level of which it branches, one half continuing upward
and forward towards the commissural region, the other turn-

Kenyon, The Brain of the Bee. 203

ing outward and becoming lost in the surrounding fibrillar sub-
stance.

XXIX. <A group outside of the last and behind the ori-
gin of the labial nerve sends a band of fibers nearly half way
through the mass behind the root of the nerve.

XXX. Between the origins of the labial and the maxil-
lary nerves and outside of them on the lower lateral surface is
a large group whose fibers forming a well marked band pass
inward and then upward near the root of the maxillary nerve
and then upward and inward and apparently forward towards
the commissural region.

XXXI. Considerably above the last, or on the upper lat-
eral surface and below the origin of the salivary nerve, is a group
whose fibers pass directly inwards and join those of the last
group near where these turn forwards.

XXXII. Just above the one just described and in front of
the plane of the origin of the maxillary nerves is a group that
sends a band of fibers upwards into the commissural region.

Conclusion,

From the facts detailed in the preceeding pages it is evi-
dent that even though there are more difficulties in the way of
obtaining good results than with the vertebrates, a patient ap-
plication of the bichromate of silver method will throw as much
light upon the organization of the hexapod nervous system as
it has upon that of the higher animals. By its aid during the
past winter the minute structure of the so-called mushroom bod-
ies has been brought to light and several links added that almost
complete the chain of evidence demonstrating the function of
these peculiar bodies to be that of enabling the insect to intelli-
gently adapt itself to its surroundings. They are shown to be
connected at their calices with two pairs of sensory tracts of
fibers from the optic lobes, with three from the antennal lobes
and with one, that is probably also sensory, from the ventral
nervous system. Their roots are shown by fragmentary evi-
dence, sufficient to warrant the conclusion, to be very
probably connected with the inner terminals of motor, or posst-

204 JOURNAL OF COMPARATIVE NEUROLOGY,

bly of other efferent fibers, but the exact course of the connec-
tion and the number of cellular elements composing it remains
to be demonstrated.

The central body is plainly shown to be connected with the
fibrillar arch, and possibly the ocellar glomerule, and probably
through these also with the nerves of the ocelli. Further it is
connected with the fibrillar mass in front, and with that below
it, but it does not appear to be connected with the mushroom
bodies unless it be with their roots. It receives its fibers
from cells situated above and behind it, and from some above
the antennal lobes.

The olfactory glomerule so-called, are shown to be formed
by the tuft-like terminals of the fibers composing the antennal
morulz, and in these the terminals of the fibers of the antenno-
cerebral tracts seem to play the most prominent role.

Several tracts of fibers from the optic lobes connect the
latter with other parts of the brain than the mushroom bodies,
and some of them doubtless form a part of an optic reflex
tract with fibers from the ventro-cerebron and the ventral ‘cord.

Such reflex tracts are not evident in connection with the
antennal lobes, but the positions of fiber fragments seen indi-
cate the possibility of reflex connections here also.

Some of the fibers from the ocellar nerves terminate in the
tubercles of the central body, others in the ocellar glomerule.
Some also may connect with the fibrillar arch. Some of the
large fibers pass downward and become the enormous fibers of
the dorsal surface of the ventral cord.

A tract of fibers, probably a continuation of what Binet
calls the ventral column of the ventral cord, passes upward
through the commissures and comes into connection above the
cesophageal foramen with a dorso-ventral tract to the calices of
the mushroom bodies.

A tract from the cord that is probably a branch of ‘the
ventral column passes forward to the posterior part of the an-
tennal lobes giving off fibers on their branches along the way
among the terminations of the fibers passing into the oral and
the antenno-motor nerves.

Kenyon, Zhe Brain of the Bee. 205

In the ventro-cerebron of the bee there is recognizable but
one root to each of the oral nerves. Of these that of the max-
illary nerve is most prominently, and that of the mandibular
nerve the most meagerly, developed. The roots connect with
the ventral column as described by Binet (94) for one of the
branches of the double root recognizable in the Coleoptera.

Motor cells have been found in a ventral position in the
ventro-cerebron, which does not accord with the distinction,
based upon physiological experiments by Faivre (57) and Binet
(94) of a dorsal motor anda ventral sensory area for each gan-
glion of the ventral cord. This is reconciled by pointing out
that it is the fibrillar connections that are destroyed in the le-
sions produced dorsally, and the association cells and fibres and
the terminations of sensory fibers in ventral lesions. If exper-
iments be performed destroying individual cells and thus pro-
ducing a consequent degeneration of their individual fibers, it
will probably be found that the ventral surface of a ganglion
may be described as a motor area.

Bibliography.

296. BrECHTEREW. Die Lehre von den Neuronen und die Entladungs-
theorie. Neurol. Centralbl., 50-57 and 103-113.

°82. BeLLoncr. Intorno alla struttura e alle connessione dei lobi olfattori
negli artropodi superiori e nei vertebrati, Reale Acad, d. Lincet, 1881-2, Sr. 3,
XIIL, 555-564.

°78. BERGER. Untersuchungen iiber den Bau des Gehirns und der Ret-
ina der Arthropoden, 47d. d. zool. Inst. Wien u. Triest, 1, 173-220.

295. BERKLEY. Studies on the Lesions Produced by the Action of Cer-
tain Poisons on the Cortical Nerve Cell. Bratz, LXXII, 473-496.

°95. BrETHE. Studien iiber das Centralnervensystem von Carcinus mzenus
nebst Angaben iiber ein neues Verfahren der Methylenblaufixation. Arch, ff.
mtikr, Anat., XLIV, 579-622; Zetts. wiss. Mikr., XII, 130-132.

°94. BINET. Contribution a l’étude du systéme nerveux sous-intestinale
des insectes. Journ, 1 Anat. Phys., XXX, 449-580.

°76. BRANDT. Anatomical and Morphological Researches on the Nervous
System of Hymenopterous Insects. Ann. Mag. Nat. Hist., 4 Ser., XVIII, 504-
506.

°94. CHILD. The Antennal Sense Organs of Insects. Am, Wat., XXVII,
608-609 ; Abstr. from Anat. Anz., XVII, 35.

206 JOURNAL OF COMPARATIVE NEUROLOGY.

°88. CuccaTiI. Ueber die Organization des Gehirns der Somomya ery-
throcephala. Zezt. f. wtss. Zool., XLVI, 240-269.

°76. DieTLt. Die Organization des Arthropodengehirns. Zezts. f. wiss.
Zool., XXVIII, 488-517.

°50. DuyARDIN. Mémoire,sur le system nerveux des insectes. Ann, Sci.
IMT5 Bele DAO HOS Se SEG, 1 1%,

°57. FAIvre. Du cerveau des Dytisques considéré dans ses reports avec
la locomotion. Amn. Sct. Nat., VIII, 245-274.

978. FLOEGEL. Ueber den einheitlichen Bau des Gehirns in den verschied-
enen Insekten Ordnung. Ze?ts. f. wiss. Zool., XXX, Supplement, 556-592.

9974. Foret. Les Fourmis de la Suisse. Lyon.

995. HOoLMGREN. Die Tracheen Endverzweigungen bei den Spinndrtisen
der Lepidopterenlarven. <Axat. Anz., XI. 340-346.

°96. KopscH. Erfahrungen iiber die Verwendung des Formaldehyds bei
der Chromsilber-Impregnation. Anat, Anz., XI, 727.

°95. LENHOSSEK. Der feineren Bau des Nervensystems im Lichte neuester
Forschungen. 2d Ed.

°64. Leypic. Vom Bau des Thierischen KGrpers. 232 et seq.

°79. Newton. On the Brain of the Cockroach. Quart. Journ. Micr, Sci.,
N.S., XIX, 340-356.

980. PACKARD. The Brain of the Locust. Second Rep. U. S. Ent. Com.,
223-242.

975. RasBL-RUECKHARD. Studien tiber Insektengehirne. Azchert and Du
Bois-Raymond’s Arch. f. Anat., 488-499.

990. RetTzius. Zur Kenntnis des Nervensystems der Crustaceen. fol.
Ontersuch., N. F., I. No. 1.

*92a. RetTzius. Die Endigungsweise des Reichnerven. Biol. Untersuch.,
Iie 18G5 WME INOS 25 ANNIE OS

°92b. ReErzius. Ueber die sensiblen Nervenendigungen in den Epithe-
lien bei Wirbelthieren. ol. Untersuch., N. F., 1V, No. 5, p. 40.

995. RetTzius. Zur Kenntnis des Gehirnganglions und die sensiblen Ner-
vensystems der Polychaeten. zol, Untersuch., N. F., VIII, No. 2. :

990. SartntT-REMy. Contribution a étude des cerveaux chez les arthro-
podes tracheates. Arch. Zool. Exper. et Gen., 2d Ser., V, 4th Memoir.

987. VIALLANES. Le cerveau de la Guepe (Vespa crabro et vulgaris).
Ann, Sci, Nat., 7 Ser., II, 5-100.

988. VIALLANES. Le cerveau du Criquet (Oedipoda coerulescens et Cal-
optenus italicus). Amn. Sct. Nat., 7 Ser., IV, 1-120.

°93. VIALLANES, Etudes histologigues et organologiques sur les centres
nerveux et les organs des sens des animaux articulés. Ann. Sct. Nat., 7 Ser.,
XIV, 405 et seq,

Kenyon, Zhe Brain of the Bee.

207

EXPLANATIONSOF PLATES.

EXPLANATION OF COLORS.

Red. Cells and fibers of the mushroom bodies.

Blue.
Violet.
parts of the nervous system.
Green.
Brown.

Sensory fibers from cells outside of the central cerebral mass,
Tracts connecting the calices of the mushroom bodies with other

The superior dorso-cerebral commissure.
Motor and other efferent fibers.

Black.: Association and miscellaneous fibers and cells.

EXPLANATION OF ABBREVIATIONS.

a. c.—Anterior commissure.

a 4.—Anteror roots of the mushroom
bodies.

a. t. c.—Antero-inferior dorso-cerebral
commissure.

A, Z.—Antennal lobe.

a m.—External antenno-motor nerve.

a. m',—Internal antenno-motor nerve.

a, s,—Antenno-sensory fibers.

c. 6 —Central body.

c. ¢.—Fibrillar arch.

c.cb.—Commissure of the central body.

clx.—Calices of the mushroom bodies.

d. v.—Dorso-ventral tract.

e. clx.—Calices of the outer mushroom
bodies.

F,.—Oesophageal foramen.

g. ch.—Tubercles of the central body.

#. cle.—Calices of the inner mushroom
bodies.

z.4.—Inner roots of the mushroom
bodies.

#. o. c.—Inferior optic commissure.

7,—Labial nerve.

/.cbh,—Lower portion of the central
body.

7, t,2g.—The antero-posterior
tract.

ma,—Mandibular nerve.

mx.—Maxillary nerve,

optic

o' o? and o’—Antenno-cerebral tracts.
o' inner, o? middle, o? out-
er.

o, 6,—Olfactory bodies or glomerulz.

o. c.—Ocelli, oc.! median; oc.? right,
oc. left.

oc. w.—Posterior group of fibers from
the ocelli.

op. 6.—Optic body.

p-—Posterior nerve.

p.t.c.—Postero-inferior dorso-cerebral
commissure.

p. o. t.—A posterior optic tract.

r, 0. g.—Region of the ocellar glomer-
ulze.

s.—Stomatogastric nerve.

s. n.—Nerve of the salivary glands.

5. 0. ¢.—Superior optic commissure.
5.@. g.—Ventro-cerebron or subceso-
phageal ganglion.

t. op. 6.—Anterior optic tract (to the
optic body).

st,—Stalks of the mushroom bodies.

m, c.——The superior dorso-cerebral com-
missure.

wu. c. 6.—Upper portion of the central
body.

uw. ¢. 2¢.—Antero-superior optic tract.

u. t. 3¢.—Postero-superior optic tract.

v, ¢.—Ventral column.

z.—Small cells of mushroom body.

208 JOURNAL OF COMPARATIVE NEUROLOGY.

PLATE XIV.

Fig. 1. Frontal section several sections in front of the junction of the
roots and stalks of the mushroom bodies, showing association fibers in the me-
‘dian region, and the antennal morula. 7. Tract of fibers from cells behind the
stalks to the anterior root of the mushroom bodies ; ¢., large trachea piercing
the ocellar nerves and the dorsal region of the brain. s, Median nerve of the
stomatogastric system; z, pyramid of small cells of the mushroom body. Pre-
pared by the formol-copper-hzematoxylin method.

Fig. 2, Frontal section through the stalks and inner roots of the mush-
room bodies, embracing the superior and the antero-inferior dorso-cerebral com-
missures. Same method as fig. I.

Figs. 3 and 4. Frontal section. The two anterior roots of the mushroom
bodies, showing the bands produced by the bushy terminations of the associa-
tion fibers. By a modified Weigert method.

PLATE XV.

Fig. 5. Frontal section just behind the inner roots of the mushroom bod-
ies, showing the fibers radiating from the central body. By the formol-copper-
hematoxylin method.

Fig. 6. <A frontal section further back, embracing the inferior optic com-
missure and the middle and the outer antenno-cerebral tracts, Same method.

PLATE XVI.

Horizontal sections, all by the formol-copper-hzmatoxylin method.

Fig. 7. Section cutting off the inner calices of the mushroom bodies and
embracing the superior dorso-cerebral commissure and the top of the central
body. c. cb, commissure of the central body.

Fig. 8. A section at a lower level embracing the top of the fibrillar arch.

Fig. 9. A section embracing the posterior commissure of the central body
and passing just through the top of the lower portion of this. The ‘‘ pillars”
of the fibrillar arch appear on either side of the light tract formed by the large
fibers of the ocellar nerves. ~

Fig. ro. A section embracing the two inferior dorso-cerebral and the lower
optic commissures, and two of the posterior optic tracts. The salivary nerve
appears in the upper right hand corner as a light spot.

PLATE XVII.

Fig. 11. A frontal view of the brain exclusive of the outer portion of the
optic lobes as a transparent object, showing the different bodies in dotted black
outline and the fiber tracts in colors. For an explanation of the latter see expla-
nation of colors. General outline and the outlines of the calices taken from a
camera drawing of a brain mounted zz fofo in balsam. The outlines of the
other bodies and the fiber tracts taken from sections prepared by the formol-
copper-hzmatoxylin method and reconstructed by the aid of millimeter paper
and by the superimposition of camera drawings.

Kenyon, Zhe Brain of the Bee. 209

PLATE XVIII.

Fig. 12. A thick horizontal section embracing the region from the base of
the inner mushroom bodies to the middle of the optic bodies. Outlines from
formol-copper-hzmatoxylin sections as in fig. II.

PLATE XIX.

Fig. 13. The remainder of the brain below that represented in fig. 12.
Outlines from sections as in fig. 12.

PLATE XX,

fig. 14. The lateral half of the brain viewed in optical sagittal section
from the median plane outward. Outlines from thick sections prepared by the
Golgi method.

PEATE XXI.

Cells and fibers from camera drawings of bichromate of silver preparations.
Fig. 15. Cells and fibers from the antennal lobe. x 121.

fig. 76. Fibers from the antennal nerve and an olfactory body. {In the
section the right hand branch of the upper fiber was found, after the drawing
here was made, to end in a small tuft of branches forming a portion of a glom-
erulayx 20).

fig. 17. Terminations of an association fiber in the junction of the stalks
and roots of the mushroom bodies. x 121.

fig. 78. Cells and fibers of the mushroom bodies. x 102.
Fig. 19. Cell bodies of the same. x 121.

Fig. 20. An olfactory glomerula formed by the termination of a fiber of
one of the antenno-cerebral tracts.

Fig. 21. The terminations of association fibers in the anterior root of the
mushroom bodies.

Fig. 22. A fiber passing across the top of one of the anterior roots and
branching profusely in the region just inside of it. Some of the branches seem
to penetrate the root.

fig, 23. Fibers terminating in the calices entering about the origin of the
stalk.

Fig. 24. A drawing from three superimposed sagittal sections embracing
the region from near the median line to the outer side of the anterior root. g,
cells on the outside of the antennal lobe; above them and obscuring their fibers
is a mass that may be composed of several over impregnated cells just above the
antennal morula. For the rest see the diagrams in plates XVII to XX.

fig. 25. Fiber entering an anterior root and apparently fusing with the
parallel fibers. See text, p. 161.

Fig. 26. The smaller kind of fibers terminating in the calices, x 102,
See text, p. 157.

210 JOURNAL OF COMPARATIVE NEUKOLOGY.

Fig. 27. The terminations of the same magnified about 586 diameters.

Fig. 28. Association fibers terminating in the anterior roots. This figure
should be viewed from the adjacent corner of the plate. See text, p. 160.

PLATE XXII.

Fig. 29. Tracheal terminations in the calyx of the mushroom bodies, x
Io2. Frontal section.

Fig. 30. Fiber 36 of diagrams. x 121. Sagittal section.

Fig. 37. Fibre 10 of the diagrams. x 102. It originates from a cell sit-
uated above the antennal morula. Sagittal section.

Fig. 32. Fibers from an oblique horizontal section, One with arborescent
terminations in the central body. Two passing from one inner root to the re-
gion above the anterior root of the opposite side. One passing forwards over
the central body and branching in the region in front of it.

Fig. 33. A twisted fiber from the region below and behind the optic body.
Sagittal section.

Fig. 34. Fiber from a sagittal section. x 121. It passes below an inner
root and sends a branch up over the union of the same with the stalks.

Fig. 35. Fiber passing antero-posteriorly below the central body and send-
ing several branches up in front of the latter. x 121.

Fig. 36. A portion of a motor fiber with its cell-body. See text, p. 174.

Fig. 37. Fiber from the antennal region terminating arborescently in the
central body. From a frontal section. x 121.

Fig. 38. Fibers of the posterior inferior dorso-cerebral commissure.
x 102.

fig 39. Fibers apparently belonging to the antenno-motor nerve, and one
commissural fiber of the ventro cerebron.

Fig. go. Three fibers from two consecutive median sagittal sections. All
three are seen to send a process each into the central body. A fragment in the
lower part of the figure may be a portion of the outer or right hand fiber of the
upper part of the figure. x 121.

Fig. 41. A fiber from the base of the central body sending long branches
down into the ventro-cerebron and to the anterior portion of the ventral cord.
x 121.

Fig. gz. Two fibers terminating in a so-called ocellar ganglion, x 121.

Notg.—On page 174, line 8, for ‘“(p. )” read ‘‘(p. 161).”’
ERRATA,

Page 133, line 5, add 1895-6.
“184, ** 21, for Grylotalpa read Gryllotalpa.
«192, ‘* 22, delete the copper-.
Seo eee Ons. eco sani dl eae
“192, ** 26, for Samomya read Somomya.
210, delete the note at the foot of the page.

THE ORIGIN AND GROWTH OF BRAIN CELLS IN
PAP VADULT BODY:

‘By Howarp AYERS.

No part of our anatomical knowledge has had such slow
growth as that pertaining to the origin and growth of brain cells
and their ultimate relations to one another and to the rest of the
body.

The current theory holds that after the nerve cell once
sends out its axis cylinder fiber and becomes a functional cell it
is incapable of division or further reproduction. For example
in the case of the human embryo it is stated that beginning
with the fourth week the neuroblasts continue rapid growth up
to the third month of fcetal life after which time no increase in
numbers takes place. All increase in the brain or its parts
after this period is due to the increase in size of the nerve cells
(from one to 500 times their original size), the increase in the
length and size of the sheaths of Schwann and the medullary
matter, the growth of the blood vessels and the neuroglia ele-
ments and the connective tissue additions to the brain.

Double Auditory and Electric Ganghon Cells.

In a former publication’ I figured and described some of
the cells of the cochlear ganglion as multipolar and in some cases
even as double cells. These latter cells were found to be com-
posed of two nucleated cell bodies closely connected by a short
connecting bar of protoplasm, in appearance like the peripheral
and central fibers given off from the other ends of these two cells
(Gi loc. ct, PIT, fig: 6, x). The origin of these double cells
I was ‘unable to trace at that time but their occurrence in the
ganglion was of interest to me in connection with the explana-
tion of the origin and relations of the hair cells. In my recent

1The Auditory or Hair Cells of the Ear and their Relations to the Auditory
Nerve, /Journ. Morph., Vol. VIII, No. 3, 1893.

212 JOURNAL OF COMPARATIVE NEUROLOGY.

studies in the anatomy of the Torpedo brain similar double cells
have again come under observation and it is the significance
of these cells in the solution of the problems of brain
-growth and especially the histogenetic processes which are in-
volved to which I wish to invite special attention. I have been
able to determine that these double cells in the Torpedo brain
may by their complete separation from one another become the
ordinary ganglion cells of the brain. In the figures which I
shall publish soon, some of the cells are reproduced with great
care. All the figures are camera drawings, and are taken from
sections of the brain of an adult Zorpedo occidentalis, the sec-
tions being stained by Weigert’s method. No single case of
the karyokinetic process (in the nucleus) has been found in my
preparations but the other relations and conditions of the cells
leave no doubt that here in the Torpedo brain functional cells
actually divide in the manner so well known for ordinary tissue
cells. The stages of cell division which occur in the electric
lobes are as follows:

(1). Large motor cells, not to be distinguished from the
ordinary functional cells except by the size of the nucleus and
cell body.

(2). Cells of the same size as (1) but with two nuclear
bodies. Both may be close together in the centre of the cell
or widely separated and lying near the periphery of the cell.

(3). Cells showing an evident constriction of the proto-
plasmic body between the nuclei as though about to divide.

(4). Double cells with short connecting bars which. are
usually large and band-shaped.

(5). Double cells in which the connecting bar is drawn
out into a thin filament, tapering conically from either cell body
towards the other.

(6). Since each nerve cell of the brain and ganglia has a
peri-lymphatic capsule surrounding it, when the cell body is cut
into two the peri-lymphatic space is not at once doubled but
the two cells still lie in a common cavity. Because of this it is
possible to trace the genetic relation of these electro-motor cells
even after they have completely separated by the breaking of

AYERS, Origin and Growth of Brain Cells. 213

the connecting bands, as in those cases where the nerve cells
become completely separated. Ultimately of course the lym-
phatic spaces divide also by completing the capsular wall close
about each cell.

The Diviston of the Cell.

Incisions of two very different kinds are found in the
bodies of the electro-motor cells. Those produced by cell
fission and those produced by unequal growth in response to
local pressure upon some part of the cell by blood- Wessels or
nerve fibers from some neighboring cell.

Relation to Blood-vessels.

The large ganglion cells of the Torpedo brain have appar-
ently approached the limit of the size of nerve cells, which
require, as we know, specially good facilities for nutrition
(respiration and excretion included). The usual vertebrate
brain is made up of cells varying in size from .002 m.m. to
jum, m. and they are disposed about ' the) courses of (the
blood-vessels in such a way as to admit of easy transfer of
food to the cells and of the nitrogenous waste products away
from the cells.

In the Torpedo’s electric lobes, however, there is added to
the usual arrangements a special feature in the relation of the
cells to the blood-vessels. It consists in the migration of the
over-grown ganglion cells to the walls of the arterial capillaries
on the surfaces of which they spread themselves out and more
or less completely surround the vascular tubes so as to present
the appearance of being more or less deeply grooved or even
perforated. The cell wall in immediate contact with the capil-
lary cells is very thin and thus the very best facilities are pre-
sented for the performance of the physiological activities of the
brain cells.

One of the anatomical causes of the increase in size of the
electric lobe of the Torpedo is the production of new cells
by the division of already functional electro-motor cells.
This division occurs most abundantly at the ventricular sur-
face of the lobe.

214 JOURNAL OF COMPARATIVE NEUROLOGY.

There is avery evident grouping of the cells in the elec-
tric lobes in groups of 2, 3, 4, or larger numbers up to 12 or
more. The axis cylinder processes of the members of a
‘group converge towards a common centre, indicating, I think, a
common origin from a single cell.

While most cells of the electric lobe possess a_ single
nucleus, the number having two nuclei is relatively large
(500 in each lobe). Cells with three nuclei are occasionally
found, 50 in each lobe.

The centrosome is plainly visible in some of the cells.

Morphological Laboratory, University of Missouri, Columbia, Mo., March
10, 1896.

THE INNERVATION OF THE AUDITORY EPG
LIUM: IN MUSTEEUSHGANIS, DEAGAW;

By Ao PDS MORRILT,

I wish, at this time, to give a brief preliminary statement
of the results obtained by the use of methylen blue in the study
of the auditory epithelium of the ‘‘smooth dog-fish.”’

The fibers of the auditory nerve lose their medullary sheath
on entering the sensory epithelium of the ampullae and branch
at different levels, although the branches are much more num-
erous at the base of the hair cells. From the latter branches,
many of which extend horizontally, numerous extremely fine
nerve fibers arise which end either in characteristic enlarge-
ments in contact with the proximal portions of the hair-cells or
pass between them to end free near the surface in similar but
smaller enlargements.

The nerve fiber often branches at the base of the hair-cell,
the two portions closely adhering to the cell and ending in en-
largements at nearly the same level on opposite sides of the

MorriLi, /unervation of Auditory Epithelium. 215

cell. In other cases the fiber can be traced to the cell and may
end in a single enlargement at its very base. Occasional free
nerve endings were found in the central portions of the
auditory epithelium, at a considerable distance from the hair-
cells, and end free in enlargements.

Conclusions.

(1) No continuation of the nerve into the cell was ob-
served although the cells were semi-transparent.

(2) No trace of Kaiser’s cup-like mass was found at the
base of the hair-cells.

(3) The triangular enlargements at the points where the
nerves branch are due to the nerve sheath, through which the
nerve fibers can be seen.

(4) Satisfactory evidence of anastomosis of nerve fibers
was not obtained.

(5) There are two kinds of nerve endings in the audi-
tory epithelium, the one being free near the surface and the
other ending in knob-like structures in contact with the base of
the hair-cells.

(6) No varicosities were found on the nerve fibers in the
best stained preparations, while the terminal enlargement was
always present.

Hamilton College, Clinton, N. Y.

NEURAL TERMS, INTERNATIONAL AND
NATIONAL.’

By Burt G. Wiper, M. D.,
Professor of Neurology, etc., Cornell University.

Introduction.

Five conditions have led to the preparation of this article
at this time.

$1. The American Neurological Association, at its session
in Philadelphia, June 5, 1896, unanimously adopted the Report of
the Committee on Neuronymy embodying the previous reports
of three other American committees and extending the list of
Latin terms recommended from eleven to forty ; see §8o.

$2. The Anatomische Gesellschaft, at its session in Basel,
April 19, 1895, adopted the Report of its Committee on Ana-
tomische Nomenclatur, comprising a list of Latin names for all
the visible parts of the human body (see Table VII), and pro-
vided for its revision at intervals of three years. Presumably
the Gesellschaft sanctioned the declarations of principles which
had been published by the secretary of the committee (Krause,
91, 94; see Part V.)? The list was published early in the
summer of 1895 asa part of an article, ‘‘ Die Anatomisthe
Nomenclatur,”’ by Professor Wilhelm His, constituting a ‘‘Sup-
plement-Band” to the ‘‘Anatomische Abtheilung” of the
Archiv fir Anatomie und Physiologie. Certain principles and
certain portions of the list merit high commendation; others,

1The more important parts of this article were embodied in a lecture, ‘‘The
Present Aspects of the Nomenclature of the Brain,” delivered at the Marine
Biological Laboratory, Aug. 3, 1896.

2See the Bibliography, Part IX. The date after the name of a writer de-
signates the year of publication. The joint works of S. H. Gage and myself
are indicated by W. & G., ’82, ’86, ’89.

Wiper, eural Terms. 217.

in my opinion, are to be as deeply regretted. Among the least
acceptable features are the designations and coordination of the
encephalic segments and the assignment of parts thereto;
able: We

§3. In the official action of the Gesellschaft (Part V), and
in arecent manual by the president of its committee, Professor
Albert von Kolliker are declarations against the efforts of the
American committees which may be due in part to ignorance
or misapprehension of the facts. As chairman of two of the
American committees and as secretary of a third, I may not
inappropriately endeavor to remove the impediments to a clear-
er comprehension of our position. I particularly desire to free
the committees, their individual members, and the associations
which they represent, from responsibilities not yet assumed by
them.

$4. In the article above mentioned Professor His not
only evinces a failure to comprehend the aims of the Amer-
ican committees, but also misrepresents what has been done
by me as an individual. Such misrepresentations, unless
corrected, might well, especially in Germany, impair the
efficiency of my past and present utterances upon An-
atomic Nomenclature. A correspondence begun in Decem-
ber, 1895, has failed to adjust our disagreement, and it is most
reluctantly submitted to other anatomists. In an experience of
thirty-five years this is my first scientific controversy, and I
trust it may be the last.

$5. During the quarter of a century since my attention
was first drawn to the defects of current anatomic terms my
convictions may be assigned to five different stages dating re-
spectively from 1871, 1880, 1884, 1889 and 1895. Beyond
the last I now discern no opportunity for progress except-
ing in the elaboration of details. It is my desire to devote the
rest of my life to the study of the brain, and this seems to be
a fitting time for submitting such statements of principle and
suggestions of practice as may facilitate the labors of others
upon Anatomic Nomenclature.

218 JOURNAL OF CoMPARATIVE NEUROLOGY.

§6. This article comprises nine parts as follows:
I. Definitions of certain terms employed in the dis-
cussion of Anatomic Nomenclature.
| II. Stages of the writer's terminologic progress.
III. Report of the Committee on Neuronymy of the
American Neurological Association, with commentaries.
IV. Discussion of the differences between certain terms in
that report and those adopted by the Anatomische Gesellschaft.
V. Reply to criticisms offered by the Anatomische
Gesellschaft and by its members.
VI. Correspondence with Professor Wilhelm His.
VII. List of the Neural terms adopted by the Anatom-
ische Gesellschaft and of those now preferred by the writer.
VIII. Concluding remarks,
IX. Bibliography.

Part I. Definitions.

$7. It is assumed that all who read this article seriously
are familiar with the parts of the brain referred to, and that
they have likewise a ‘‘ working knowledge” of ancient and
modern languages. But space will be saved by the employ-
ment of certain terms which are rather linguistic than anatomic,
and some of which either are comparatively new, or are here
used in new or restricted senses; these are therefore first briefly
defined. The definitions of course apply to the Latin forms of
the English words; the adjectives and other derivatives are
self-explanatory. ’

$8. Onym.—From évepa, same as veya, a name. Pro-
posed by Coues (’82) in the sense of biologic name. It is
seldom needed alone but is the essential element or base ($30)
of many derivatives.

§9. Toponym.—From onym and céxoz, place. A term
indicating location or direction; e. g. /ateral, at the side; /aterad,
toward the side ; ¢vansection, cutting across.

1 Definitions may be found also in the more recent English and medical
dictionaries. Some of the terms are discussed in my articles, ’85 and 8g.

WILpER, Neural Terms. 219

S10. Organonym.—The name of a part or organ; e. g.
humerus.

S11. NMeuronym.—The name of a part of the nervous
system.

S12. Polyonym.—A name consisting of more than one
word; e. g. fissura centralts ; rostrum corporis callost; plexus
choriotdea ventricult quarti ; iter a tertio ad quartum ventriculun.
This use of the word jpolyonym is analogous to that of poly-
anary, polygamy, etc.; see note to p. 518 0f W. &G, 89.

§13. Dionym.—A term consisting of two words; e. g.
vertebra thoracalts; arteria brachialis ; gyrus callosalis. Dionyms
are perhaps the most common kind of polyonyms. They have
a certain analogy with the technical names of animals and plants
since the noun often indicates a group of similar or related
parts and the adjective designates a specific member of the
group.

$14. Trionym.—A term consisting of three words; e. g.
vertebra thoracalis prima. Here, as with the so-called trinom-
ials of zoology, the second adjective may be said to designate
a subspecies.

$15. Mononym.—A name consisting of a single word ;
e. g. zsula. Strictly speaking a mononym is either a noun or
some other word used asa noun. But the application may be
conveniently extended as in the next definition.

$16. Mononymic Qualifier.—A qualifying word, (adjective,
participle or genitive), consisting of a single word; e. g. the
second word in each of the following dionyms: Gyrus postcen-
tralis (for G. centralts posterior); G. subfrontalis (for G. frontals
mmfertor).

$17. Ordinal Names.—These indicate the order or num-
eric location of a member of a series; e. g. costa prima; verte-
bra thoracalts prima."

1 With any series extending lengthwise of the vertebrate body the member
nearest the head is regarded as first. The only instance known to me of disre-
gard of this conventional assignment is the enumeration of the segments of
the brain in the schema of Prof. His as adopted by the German Committee.

220 JOURNAL OF COMPARATIVE NEUROLOGY.

$18. Attvibutive Names.—These refer, at least in part, to
some real or fancied attribute; e. g. callosum; oblongata;
vagus.

$19. Szmle Names.—These express real or fancied re-
semblances to other objects by means of the suffixes formzs or
oides; e. g. restiformis, trapezoides. Most simile names might
as well be converted into the corresponding metaphoric names ;
e. g. restis, trapestum.

$20. Melaphoric Names.—The names of non-anatomic
objects are transferred to parts having some real or fancied
resemblance thereto; e. g. pons, znsula, thalamus, falx.

S21. Metaphoric Diminutives.—Since many parts are
smaller than the more familiar objects whose names have been
transferred to them the diminutive form is sometimes used; e.
g. vallicula (from vallis); fasciculus (from fasczs) ; colliculus
(from collts); clavicula (from clavis). Since, however, size is so
variable and unessential an attribute, and since verbal diminu-
tives are commonly longer than their originals, the latter might
as well be employed. But this suggestion would not apply to
a case where there are two of a general sort differing mainly in
size; e. g. cerebrum and cerebellum ; falx (falx cerebrt) ; falcu-
la (falx cerebellt).

§22. Polychrestic Word.—One that does duty in many
connections; e. g., occtpttalis, which in various combinations
aids in designating at least twenty-five different parts.

$23. Homonym.—A name applied to two or more differ-
ent parts; an ambiguous term. An extreme case is that of os
as signifying either a bone or an orifice; the oblique cases and
derivatives of course distinguish them. J/edulla has been ap-
plied to several parts. Afzphysis may designate the end of a
bone or a part of the brain. Theoretically objectionable, the
context commonly frees homonyms from serious ambiguity.

$24. Jdionym.—A word which, at least in anatomy, re-
fers to but one part; e. g., cerebellum; thalamus ; chiasma ;
pons ; imsula.

$25. Ldionyms by Recombination. Cornu posterius, as em-
ployed by most anatomists, is a homonym, designating either a

WILDER, Neural Terns. 22%

cavity of the cerebrum ora feature of the myel (spinal cord).
But fostcornu, as introduced by me in 1881, applies only to the
cerebral cavity and is thus an idionym.

§26. Contextual Explicituess.—For want ofa better phrase
this may refer to the possibility of employing terms that might
be ambiguous but for their association with others. A com-
mon example is cord, which may be used in at least five senses,
by the neurologist, the laryngologist, the surgeon, the obste-
trician and the embryologist. When an entire publication or
section of it refers to a group of organs of the same general
character, then the generic element of their polyonymic desig-
nations may be often omitted and the specific alone employed ;
é. g., with arteries, fissures, gyres, cic. Indeed, to be abso-
lutely explicit or idionymic in all cases would require many
new names or the addition of genitives or other qualifiers to
many already existing.

$27. Locative Names.—TVhe location of a part is a general
and comprehensive attribute and, as remarked by Owen, ‘‘sig-
nifies its totality without calling prominently to mind any one
particular quality, which is thereby apt to be deemed, undeser-
vedly, more essential than the rest.”

$28. Prepositional Locatives.—With these the qualifying
prefix, a preposition or adverb, indicates the location of a part
relatively to some other part, more important, more easily rec-
ognized, or earlier designated. Praecuneus designates a cortical
area just ‘‘in front of’ the cuneus.

S29. Adjectival Locatives.—These indicate either the lo-
cation of a part within some general region, or its membership
of aseries. Vertebra thoracals designates a spinal segment in
the thorax. Commassura anterior, cm. media, and cm. posterior
distinguish members of a conventional series. J/esencephalon,
prosencephalon and metencephalon designate members of a natural
series, and the prepositions have the force of adjectives ; see
S$$173-192.

§30. Base (verbum basale).—The original or more essen-
tial element of a derivative, as distinguished from prefixes, suf-
fixes, inflective terminations, etc.

222 JOURNAL OF COMPARATIVE NEUROLOGY.

$31. Derivative.—A -word derived or formed either im-
mediately or remotely from another; e. g., zworganic, organize,
and organs are derivatives of organ.

$32. Correlative Names.—These are derivatives containing
no obvious locative element but intended to indicate some re-
lation between the part so designated and the part designated
by the base; e. g., fissura calcarina associates an ectal fissure
with the calcar, an ental ridge.

$33. Lponyms.—Personal names, i. e., derived from the
names of individuals; e. g., fissura Sylva; pons Varoli. Some
objections to these are stated in W. & G., ’89, §59,' and as
they are condemned by the German committee most of them
will probable disappear. An exception perhaps should be
jissura Sylvit (see $120).

$34. Pectlonymy.?—Proposed by me (W. & G., ’89, §16)
as a mononym for ferminologic variety or inconsistency within a
single article or work; e. g., the use of fisswra and sulcus for
the same cerebral furrow, of centralzs and Rolando for the same
fissure. Between pp. 464 and 507 of Schwalbe’s ‘‘ Neurol-
ogie”’ occur Crus fornicis (498), Fornix-schenkel (464), Forntx-
saulchen (507), Gewolbe-schenkel (464). His (95) adopts Fora-
men interventriculare but uses Foramen Monroi on p. 166 and
‘* Monro'schen Loche’’ on p. 167.

$35. Daurect Pecilonymy.—In the cases mentioned above
and others that might be adduced from nearly every work
known to me, one and the same part is designated by two or
more substantives or words used substantively. This is dzrect
pecilonymy. A special variety of it occurs when different gen-
eric names are applied to two homologous parts; e. g., in Hux-
ley and Hawkins’ ‘‘ Comparative Osteology”’ the arm is called
the ‘‘anterior exrtremity”’ the leg, the ‘‘ hind dd.”

”

1 There may be added the liability of misspelling ; oro has been spelled
Monroe, Munro and Munroe; see my paper, ’8o, id.

? From zozxilos, various, changeful, inconstant; compare zozxiAofovidos,
of changeful counsel ; Zectlopoda, various footed. The unfamiliar term is per-
haps the less objectionable in that it stands for a habit which may ere long be
eradicated.

WILDER, Neural Terms. 223

836. Indirect Pectlonymy.—But when a certain substantive
is used in one passage, and in another an adjective or other de-
rivative from a different substantive, the pecilonymy is indirect
or implied; e. g., ‘‘ certain fibers are called peduncular because
they pass into the cvura cerebri.’’ Very commonly a certain
fissure is named Rolando, but adjoining gyres, paracentral,
anterior central, etc.

$37. Pecilonymy by Permutation.—When a name, or the
adjective part of a name, contains two or more elements of ap-
proximately equal value, they are subject to accidental or in-
tentional transpositions that may cause misapprehension. For
example in his paper on the brain of Afzeles (Zool. Soc. Proc.,
1861) Huxley refers to the same fissure as occipito-temporal
on p. 258 and as temporo-occipital on p. 260. One might
infer that two different things were indicated just as, in chem-
istry, Aydro-carbon and carbo-hydrate have different significations.
Similar diversity of usage exists with regard to the occipital
fissure, which is called by some occifito-partetal and by others
parteto-occipital. Orbito-frontal and fronto-orbital constitute an-
other instance.

$38. <Abbreviational Pecilonymy.—The following is a good
example of a bad system: in the translations of two of
Meynert’s works occur corpus qguadrigeminum ; corp. quadrigem-
mum; corp. quadrigem.; corp. quadrig.; corp. quad.

$39. The Perpetration or Toleration of Fecilonymy may be
ascribed to five mental conditions :

A. Pure heedlessness.

B. Indifference to the just claims of readers and especi-
ally of students.

C. Pride in the hardly gained familiarity with the syn-
onymy of parts.

D. Desire to avoid repetition, as in certain forms of lit-
efahy,expresssion): see W. & G:, 80, $73, B, note:

E. Unwillingness to commit oneself to a particular’ name.

1 In some cases all the current titles of a part are so unacceptable that one
recalls Shakespeare’s epigram as to the ‘‘ Small choice among rotten apples,”

and the demand of the dissatisfied guest, ‘‘If this is tea, bring me coffee ; if it
is coffee, bring me tea,”

224 JouRNAL OF CoMPARATIVE NEUROLOGY.

Such hesitation constitutes the only valid justification of pecil-
onymy. But the same end might be gained by a simple de-
claration, without the risk of confusing or misleading the reader.

$40. Magnilogy.—The employment of lengthy or pon-
derous terms when briefer would suffice. This is simply one
form of what may be called anatomic esotery. Now that the
choice is offered, the anatomist who deliberately says aponeurosis
for fascia, anfractuosity for fissure, and convolution for gyre,
thereby arrays himself with the village orator in whose turgid
discourse a fire is always a conflagration.

$41. Pertssology.—The following example of needless
amplification occurs in a special article by a distinguished neu-
rologist in a leading metropolitan medical journal: ‘‘ The an-
terior column of gray matter extends throughout the spinal
cord, and the upper enlarged intra-cranial end of the spinal cord,
which is known as the oblong cord or medulla (medulla ob-
longata).’”’ As shown in W. & G., 89, 529, §76, the informa-
tion contained in these thirty-two words might have been given
in fifteen.

$42. LEguivalents, Synoyms, and Tsonyms.—Equivalents
are terms meaning the same thing, e. g., pons, pons Varoliz,
pont, and Lriicke. Strictly speaking, pous Varoliz isa synonym,
or equivalent in the same language, while pout and Lriicke are
isonyms or equivalents in other languages. But for simplicity
all may be here regarded as synonyms, just as, in biology, sya-
onymy embraces all the appellations of organisms, whatever
their nationality. Hence one may recognize two groups of
synonyms, viz., pavonyms and heteronyms.

$43. Paronyms and Heteronyms.—Excluding pons Varolit
(the dionymic, eponymic synonym of fons), the other equivalents
are the French font, the Italian ponte, the Spanish puente, the
German JSviicke, and the English drzdge. Of these, the first
three are obviously related to the Latin fous, while the last two
have no such relationship. The former have been called by
me paronyms,’ the latter, heteronyms; ’85, c,9; W. &G., ’86,

1 Paronymy or paronymization includes what has been called word-adoption,
word-appropriation, word-assumption, word-borrowing, etc.

Wiper, Neural Terms. 225

preface; W. & G., ’89, 519. A familiar illustration is the
Latin canals, ot which canal is the English paronym, while
heteronyms are Zube, passage, trough and water-course. The
Greek épyavov might be rendered by part, tnsteument or agent,
and these are its English heteronyms; but the Latin paronym
is organum; the French, organe; the Italian, organo; the
English, oxgan; and the German, Organ. Each of these is,
so to speak, a geographic variety of the original or antecedent
word; indeed it may be regarded as the same word modified in
accordance with the genius of each language. The case may be
compared with that of a traveller who maintains his essential
identity notwithstanding ‘‘in Rome he does as the Romans
do,’’ and in other countries conforms to the customs of the
inhabitants in respect to garb and demeanor.

$44. Methods of Paronymization.—For linguistic reasons
paronymy is general and easy with the Romance languages, less
so with the Germanic and with English. Still there are ex-
amples enough (Tables II, 1V) to warrant the belief that into
either may be adopted any Latin substantive or adjective.’
Paronymic methods vary with the language and with the word.
Some of the modes of conversion of Latin words into their
Anglo-paronyms are formulated in W. & G., ’89, §66. The
instances there given involve more or less orthographic modifi-
cation, ranging in extent from the case of fiver (from fibra) to
that of alms (from eleemosyna.) These are changed paronyms.

$45. Unchanged Paronyms.—But there are other evi-
dences of paronymization, vzz., (a) Pronunciation, e. g., Parts,
Detroit. (b) Hyphenation with a word unmistakably of another
language; e. g. in Lalken-splentum, the hyphen indicates the adop-
tion of the Latin sp/enzum asa German word. (c) Combination,
e. g., Ponusfasern and other cases in Table IV. (d) Declaration
that the writer regards the unmodified word as adopted.” (e)
‘ ‘Also other and perhaps all parts of speech, but they do not concern us
ere.

*Were all foreign words italicized, then in a given case the non-italicization
of a word would indicate its adoption. Since the Germans commonly capital-
ize all nouns, that feature does not not necessarily signify that a word is regar-
ded as an unchanged paronym; see Table.

226 JouRNAL OF COMPARATIVE NEUROLOGY.

Employment of the vernacular form of the plural or of an
oblique case; e. g., the Latin plural of Jens is dentes, but the
English is /enses; so atlas (atlantes) atlases; enema (enemata)
enemas ; animal (animatia) animals: in the phrase ‘fibers of
‘the callosum,” the last word might still be regarded as Latin;
but if one said ‘‘callosum’s fibers’? the English possessive
would indicate paronymization.

$46. International and National Terms.—By general
consent Latin constitutes a common or international language
for scientists. National terms may be either unrelated to
the Latin antecedents,’ hence heteronyms ; or obviously related
thereto, hence paronyms. Seahorse, Cheval marin and See-
pferd are synonyms (in the broader sense, $42) but to either an
Englishman, a Frenchman or a German, two of them are for-
eign words and unacceptable. Hzppocampus is distinctly a
Latin word, and the frequent occurrence of such imparts a ped-
antic character to either discourse or printed page. //zppocamp,
hippocampe, hippocampo and HHippokamp are as distinctly nation-
al forms of the common international antecedent (not to in-
voke the original Greek izzézapzos), and are readily recognized
by all, while yet conforming to the ‘‘genius”’ of each language.

§47. The Paronymic Advantages of Mononyms.—The ob-
ject of paronymy is to endow anatomic language with national-
ity without obscuring its internationality. With mononyms
the paronymic changes (if any) are slight, involving mostly the
termination, or, with German, the capitalization of nouns and the
occasional replacement of c by &. The word is readily recag-
nized, and its abbreviation would be the same in any language.
But with polyonyms the relative position of the substantive and
the qualifier is commonly reversed in the two groups of lan-
guages, Romaniform and Germaniform. In the former the
noun more often precedes, in the latter it almost always follows.’
Hence there is a different aspect of the entire term, and the

1Or related so remotely that the connection is obscure.

2Notwithstanding the familiar exceptions, a/ma mater, pia mater, and
notary public.

Wiper, Neural Terms. 2277

abbreviations are transposed. The Anglo-paronym of commis-
sura posterior is posterior commissure, and the respective abbrevi-
ations might be c, fg. and f, c.; but if the Latin dionym be mon-
onymized into postcommissura, the English paronym Is postcom-
missure, and the abbreviation fc. answers for both. See gg61-64.

$48. Lemitatiors to Paronymy.—As already admitted
Haniohe
bids the rigid and universal application of the principle of par-

with regard to mononymy (§88), the ‘‘nature of things

onymy. Certain parts, so exposed or so vital as to have gained
early and popular attention, have received vernacular names or
heteronyms which are brief and generally understood. Such
are head, hand, foot, heart and brain. Indeed the use of the
Latin equivalent for either of these would impress most persons
as pedantic. But this concession of, for example, the suffici-
ency of dvazn instead of encephalon does not warrant the reten-
tion or formation of an indefinite number of inflectives, deriva-
tives and compounds from the heteronym. The same remark
applies to other languages.’

Part Il. Stages of the Writer's Terminologic Progress.

$49. The following summary of the changes of my views
during a quarter of a century shows, I trust, a general advance
in the comprehension of the subject and justifies me in com-
menting upon the labors of others.

§5o. I. 1871-79. Inan effort to confirm, extend and
modify certain morphologic ideas of my teacher, Jeffries Wy-
man, I enumerated (71, 172) the following requirements of
technical terms: 1. Classic Derivation. 2. Capacity for In-
flection. 3. Brevity. 4. Independence of Context for Signi-
fication. 5. Non-ambiguity to the Ear as well as to the Eye.
6. Previous Use in a Kindred Sense.

Of the thirty-three names then adopted or proposed for

1 Of the two German vernacles for encephalon, Gehérn is more commonly
used alone and Arn in composition. On my list there; are 35 compounds of
Gehirn and 106 of Hirn; moreover, of the former, one-half are duplicated among
the latter.

228 JOURNAL OF COMPARATIVE NEUROLOGY.

the limbs, their segments and joints’ all were mononyms (§ 15).
With most were given the ‘singular and plural nominative and
genitive. Two, omozone and tschizone, were Anglicized (paro-
_nymized). The designation of the fingers by the adjectives, z-
dex, medius, annularts and minimus, without preposing the sub-
stantive digitus, recognized Contextual Explicitness (§ 26) and
the validity of adjectival nouns (§ 117).

$51. Then, as now, the most desirable (yet not absolutely
essential [$§ 67-70] ) attributes of technical terms seemed to
me (1) Classic Derivation, (2) Capacity of Inflection. But
both these had been adumbrated long before by Barclay (03)
and Whewell (’40), and distinctly enunciated by Owen (’46, 171)
in the immortal paragraph wherein sye/on was proposed :

‘‘The fore part of the neural axis * * is called the brain or
encephalon; the rest I term mye/on, (Greek pvedés marrow). As
an apology for proposing a name, capable of being inflected
adjectively, for a most important part [see W. & G., ’89, § 48]
of the body which has hitherto received none, I may observe
that, so long as the brief definitions, ‘marrow of the spine,’
‘chord of the spine,’ are substituted for a proper name, all pro-
positions respecting it must continue to be periphrastic, e. g.,
‘diseases of the spinal marrow,’ ‘functions of the spinal chord,’
instead of myelonal [myelic]? diseases, myelonal functions; or
if the pathologist speaks of ‘spinal disease,’ meaning disease
of the spinal marrow, he is liable to be misunderstood as refer-
ring to the disease of the spinal or vertebral column. But were
the anatomist to speak of the canalin the spinal marrow of fishes
as the ‘myelonal canal’ he would at once distinguish it from
the canal of the spinal column. The generally accepted term

‘ Among the few new terms were omos, for shoulder-joint, and omozona and
éschizona, for shoulder-girdle and pelvic-girdle respectively. They still seem to
me preferable to the ‘* Articulatio humeri,” ‘* Cingulum extremitatis supertoris”
and ‘‘ Cingulum extremitatis inferiorts’’ of the German list.

? On several previous occasions (’85, 354; ‘85, 12; ’89, 531) I have shown
that analogy with words like angel and angelic (from 4yyeoc) calls for myel and
myelic as the English nominative and adjective of myelon ; myelonal is clumsy,
and analogy would involve the replacement of encephalic by encephalonal.

WILpvER, Neural Terms. 229

‘chorda’ or ‘chorda dorsalis,’ for the embryonic gelatinous
basis of the spine, adds another source of confusion likely to
arise from the use of the term ‘spinal chord,’ applied to the
myelon, or albuminous contents of the spinal canal.’”

§52. In 1873 (’73, 306) Owen’s examples of ectogluteus,
mesogluteus and entogluteus \ed me to propose the locative mono-
nyms ectopectoralis and entopectoralis for the two frequently
named muscles whose relative proportions in most mammals
are so misrepresented by the adjectives major and munor.

$53.) Wh haveialneady(/85,.\¢, 51190; 2, 1) expressed my
sense of obligation to Owen’s terminologic precepts and exam-
ples, and my regret that the limits of the article, ‘‘ Anatomical
Terminology”’ (W. & G., ’89) did not permit even more ex-
tended selections than are embraced among the ‘‘ Aphorisms
respecting Nomenclature”’ therein.

$54. II. 1880-1883. While preparing a paper on the
brain of the cat (’81, @) and (with S. H. Gage) a volume of
directions for laboratory work (W. & G.,’82) I adopted from
Barclay (’03) the unambiguous toponyms (§9) dorsal, dorsad,
etc.; replaced his meszon by meson, the direct paronym of péoov;
added ectal, ental, etc.; and simplified some organonyms, espe-
cially muscular (W. & G., ’82, 207) and neural (’80, f; ’81, 4, a)
in the following ways: (a) Dropping unessential adjectives
( optecus from thalamus and chiasma); eponymic (§33 ) qualifiers
(Varolit, Reilit, Rolando); and generic nouns (corpus, mater, and
membrana ) from adjectives which were sufficiently distinctive
and could be used as substantives (callosum, dura, mucosa) ;
(b) substituting prepositions for adjectives (e. g., postcommius-
sura for commissura posterior); (c) Replacing certain polyonyms
by mononyms more or less nearly akin thereto (e. g., damina
terminalis by terma); and (d) Abandoning the anthropotomic
misnomers of the encephalic cavities in favor of mononyms co-

1 The foregoing first appeared half a century ago; the mononym mye/on was
employed consistently by Owen, and on at least one occasion by his rival, Hux-
ley (’72, 65). These facts should secure for it the consideration due to high
authority and moderate antiquity, and forestall any hasty proposition to employ .
it in a different sense.

230 JOURNAL OF COMPARATIVE NEUROLOGY.

ordinated with the commonly accepted titles of the encephalic
segments (e. g., Aguaeductus Sylvit and Iter a tertio ad quartum
ventriculum for mesocoelia )'

§55. In respect to terminologic practice, before the publi-
cation of any paper or book there was made a list of the Latin
terms to be employed, with abbreviations thereof, and these
were adhered to throughout.

§56. Notwithstanding their defects, these efforts to im-
prove anatomic language elicited favorable comment, helpful
criticism, and more or less actual adoption from Oliver Wendell
Holmes (’81), Joseph Leidy (’85, ’89),? Henry F. Osborn
(’83, ’84), E. C. Spitzka (’81) and R. Ramsay Wright (’85).

$57. Ill. 1884-1888. Although now satisfied as to the
correctness of the general system and as to the excellence of
most of the individual terms, I began to realize more fully the
magnitude and difficulty of the task and the necessity for coun-
sel and cooperation. In the summer of 1884, at my sugges-
tion, committees were appointed by the American Neurological
Association and the American Association for the Advance-
ment of Science. The constitution of these committees (§ 80)
insured that no hasty action would be taken, and warranted the
hope that any conclusions reached by them would be consid-
ered seriously here and abroad. Personal conferences were held
when practicable, but most of the work of comparing views and
preparing preliminary reports was done by correspondence.

$58. As collaborator on a medical dictionary (Foster,
"88-'94), I undertook to obtain a list of names already applied
to parts of the central nervous system. In 1888 the total was
10500, distributed as follows, in round numbers: Latin, 3100;

1 Nothing in my terminologic experience has been more gratifying and en-
couraging than the approximate coincidence of a similar proposition by T. Jef-
fery Parker (’82, ’84.)

? While engaged upon the new edition of his ‘‘ Anatomy,” Professor Leidy
wrote to me under date of Jan. 20, 1885: ‘‘I wish to aid in reforming the
nomenclature of Anatomy, and in doing so propose to Anglicize the names to
some extent (246). Will you please look over this list of muscles and tell me
whether I can do better with any of the names.’”’ Ten days later he submitted
a list of the many terms. Many of my suggestions were adopted.

WILDER, WVeural Terms. 231

English, 1800; French, 1800; Italian and Spanish, 900; Ger-
man, 2900. Assuming the number of parts or features to be
500-600, there were evidently many superfluous neuronyms,
especially in Latin and German. ‘The excess in these two lan-
guages might be accounted for in part by the international
character of the former, and by the large number of publica-
tions in the latter.

§59. Buta careful scrutiny disclosed two other causes :
(1) Many of the Latin names, especially the older, comprised
so many words as to constitute descriptive phrases, and to fur-
nish opportunity for conscious or unconscious abridgement and
permutation (§ 37); each resultant combination had to be re-
garded asaname. In W. &G., ’89 $56, are enumerated no
less than twenty-three distinct Latin names for the fibrous
bundle connecting the cerebellum with the oblongata; they
average nearly 2.7 words each."

§60. Of the German names a small proportion (58, or
two per cent. of the total) had any obvious resemblance to
equivalent Latin terms (/7ssur to fissura, Commussur to Com-
missura, Centralcanal to Canalis centralis); the vast majority
were vernacular translations (e. g., Briicke, Schenkel, Seepferd-
efuss, Sehhiigelpolster).” Different writers made different trans-
lations, and considerable variation occurred in different parts of
the same publication (§ 34). Hence there arose a multitude of
terms, acceptable and intelligible only to readers of the same
nationality, and bearing no relation to the original or interna-
tional Latin terms. Ina greater or less degree the same might
be said of the other modern languages.

S61. It will be seen that two opposing influences were
operating. Each anatomist preferred to employ terms belong-
ing to his own language ; at the same time he preferred that
other anatomists should employ Latin terms with which he was

1 All these might be replaced by the single word, postpedunculus.

2 Without imputing even so worthy a motive as national self-satisfaction,
the effect was asif certain neurologists had yielded to a desire to confer upon
the printed page an obtrusively German aspect.

232 JOURNAL OF COMPARATIVE NEUROLOGY.

already familiar, or which were intelligible without an intimate
acquaintance with other modern languages than his own.

§62. With a view to reconcile these two opposing ten-
~ dencies I formulated (’85, c) the distinction between heteronyms
(§ 43) and paronyms (§ 44), and proposed that, with few ex-
ceptions (§ 48) heteronyms should be discarded in favor of
paronyms. ‘‘Since each paronym suggests the original Latin
name, the latter forms a bond of intelligence between writers
and readers of different nationalities.”

§63. The international advantages of paronyms over het-
eronyms have been distinctly recognized, and the principle in-
dorsed, by the American branch of the International Committee
of Biological Nomenclature, and by the American Association
for the Advancement of Science (Proceedings, 1892, 233).

$64. That mononyms are more readily and uniformly
paronymized than polyonyms, and dionyms than other polyo-
nyms, has been already mentioned (§ 47) and is indeed self-
evident.

$65. IV. 1889-1894. But the recognition of the nature
and causes of neuronymic hypertrophy and deformity, and
even the formulation of general principles of relief, still left un-
accomplished the necessary operations of excision and correc-
tion. My inability to decide in season which should be re-
garded as the names, and which as merely synonyms, was one
of the reasons for not accepting the invitation of Dr. Foster to
frame the definitions in the dictionary above mentioned. Par-
tial lists had been prepared in connection with the ‘‘ Anatomi-
cal Technology” (W. & G., 82, 436-438) and the ‘‘Cartwright
Lectures’ (’84, @). The latter list (84, 2) contained 115 names
exclusive of the fissures and gyres and blood vessels. In con-
nection with a paper, ‘‘Owen’s Nomenclature of the Brain ”
(90, g), there was presented to the Association of American
Anatomists a ‘‘ Macroscopic Vocabulary’ of about 200 names,

1 The history of the process, and the names of my present and former col-
leagues who so materially assisted me, are given in several publications (’85, ¢;

W. & G., ’86; ’89).

WILDER, Weural Terms. 233

with synonyms and references (’90, %). The vessels, fissures
and gyres were estimated at 140, and lists of them were pub-
lished at various periods (85, ¢, A, g; ’86, g).

$66. This made a total of about 340 parts or features of
the central nervous system the designations of which I had se-
lected or framed from among the vast accumulation of available
terms. These names had already been found serviceable in the
research and instruction carried on under my direction; and
they were embodied in the articles on the gross anatomy of the
brain (89, @, 0, c; 93, @, &, c); and questions involved in their
adoption were discussed at length in ‘‘ Anatomical Terminol-
ony (W.)&'G., ’So).

$67. V. 1895-1896. Among the requirements of tech-
nical terms enumerated in 1871 was ‘‘Independence of Context
for Signification.”” The rigid application of this would exclude
all homonyms (§23,) and would require every term to be
absolutely explicit. It was perhaps not unnatural for a com-
parative beginner in the subject to make such a rule, and, hav-
ing made it, to adhere to it somewhat persistently as in the
following cases (S$68-70).

$68. Of the three current appellations, conarium, epiphy-
sis and corpus pineale, the last was rejected unhesitatingly asa
polyonym, and the second as applying equally (without the
qualifier cerebrz) to the separable end of a growing bone; as
recently acknowledged (’96, 6) I long resisted the precept and
example of H. F. Osborn and E. 'C. Spitzka in favor of epzph-
ysts as correlative with hypophyszs, and failed to recognize the
full force of Dall’s remark, ‘‘The human mind wearies of too
many names and much more readily assimilates a new meaning
for an old one,”’ although it was printed as Aphorism XV in
Wer eerGi 89). 15 20;

$69. Likewise, although favoring the general plan of ren-
dering the Latin ae and oe by e in Anglicised (paronymized)
words,’ I retained the diphthong in coea and its compounds

In this country no medical writer has more persistently and vigorously
urged this simplification than the former editor of the (Phil.) Medical News
Gould, G. M., ’94, ’96.

234 JOURNAL OF COMPARATIVE NEUROLOGY.

(from xocdéa, a cavity) for the sake of distinguishing them from
the derivatives of x/j7j, a tumor. I now frankly acknowledge
the non-necessity of the diphthong even for the discrimination
of encephalocele, the normal cavity of the brain, from the same
word signifying an abnormal protrusion of the organ.'

§70. In August, 1884 ('84, a, 114) I proposed to replace
the common polyonym azzs cerebro-spinalis, and even Owen’s
myelencephalon, by the brief mononym xeuron, warranted by nex-
ralis, neurenterica, etc. and correlated with exteron (canahs al-
mentaria) and axon (axis somatica). The term was used by
Minot (’92, 606); Stowell (85); Waters (’91,362) and others.
Its abandonment by me in favor of newraxis (’89, @) was due
to two later observations: (a) the prior use of xeuraxzs* in the
same sense: (0) the prior application of xeuvon to a part of an
invertebrate eye. I have since been led to believe that I was
unduly influenced by these considerations. Unfortunately the
matter is now complicated by (a) the application of xeuron to
the entire nerve-cell including its processes, and (0) the designa-
tion of the ‘‘axis-cylinder process” by xeuraxon, easily con-
founded with neuraxis.* I have already declared (’93,100,
95, ¢’45) my lack of personal feeling in the matter, but the
more I think of it the greater appear to me the advantages of
neuron. In view of the practical efficiency of ‘‘contextual ex-
plicitness” (§26), its ‘‘invertebrate’’ use may be ignored, and
where there could be any doubt as to whether xeuvon referred
to the entire nervous axis or only to one of its histologic con-
stituents smacroneuron and wmucroneuron might be employed.
Cases not strictly analogous, and yet worthy of note in this con-
nection are the general use of Jody and belly for parts of a mus-

1Those who are interested in vicissitudes of opinion may think I ought to
admit that for a certain intermediate period the e alone was used in the paron-
yms of coelia; 84, a.

7In the ‘‘Dictionnaire de Medicin” of Robin and Littré occurs névraxe, the
Galloparonym of a potential antecedent, mewraxis; but neither the propounder
nor the first adopter is named.

’For some history and discussion of these and kindred terms see the papers
of Fish ('94) and Baker (’95).

WILDER, WVeural Terms. 235

cle; and of ¢arsws and cz/um in both macroscopic and micro-
scopic senses. Whatever may be the outcome I shall always
regret the confusion arising from what I now regard as a mani-
festation of excessive conscientiousness.

S71. Terms Withdrawn.—TVhrough ignorance, misappre-
hension, timidity, or over-confidence, I have at various times pro-
posed or employed needless or objectionable terms. Their for-
mal withdrawal is here made in accordance with a conviction
which was expressed (’91,a@) five years ago: ‘‘Since every
one makes mistakes, the interests of all concerned would be
subserved by the adoption of the custom of each correcting his
own, either as soon as discovered or periodically ; a sort of sci-
entific confession of sins. The natural corollary to this would
be that each well-disposed discoverer of another’s fault would
inform him privately so that he might make prompt correction.
This plan I have followed in several cases, and have reason to
believe it has served to avoid personal irritation and the need-
less repetition of criticism.”

§72. The following terms are hereby withdrawn: //yfo-
campa (for hippocampus [mazjor]); W. & G., ’86, 4000; Spitzka,
84; Vicq d’Azyr, 1786, 61, e¢ seg. Torus (for tuber [ctnereum)).
Lenum (for torcular | Herophil’]|;’84). Cerebrocortex (for cortex
cerebri or cerebral cortex). Cerebellocortex (for cortex cerebelli or
cerebellar cortex. Comimissure habenarum (for supracommissura);
W. & G., 86,4008. Mediventricle (for ‘‘third ventricle’’); ’80, d
Lativentricle (for ‘‘lateral ventricle”); 80 ad. Procele (for para-
cele); ’84, c; W. &G., '86, 400. Coele and its compounds (for
cele and its compounds); (§69). ‘

§73. If the foregoing list of my verbifactive sins appears
damagingly large, let the critics scan their own records with
equal closeness; I have at least been consistent within the lim-
its of a single publication.

$74. Fifteen years ago I was so oppressed by the length
and obtrusive Latinity of the current names for the segments
of the brain, prosencephalon, etc., as to suggest (’81, 4) that they
might sometimes be abbreviated to prosen., etc. Three years
later, in accordance with the analogies of quad (for guadrangle),

236 JOURNAL OF COMPARATIVE NEUROLOGY.

grog (for grogram), photo (for photograph), stereo (for stereotype),
and consols \(for consolidated annuities), I ventured (84, 4) to
drop the sign of abbreviation and to use these verba decaudata
as real words. Their withdrawal a year afterward (854,
354) may have been due partly to the horror of some anatom-
ic friends in whose eyes they were needless and indefensible
‘nicknames ;’’ but I was influenced mainly by the revulsion
attendant upon the formulation of the principle of paronymy
whereby the shorter prosencephal, etc., were legitimized. Yet
I anticipate the eventual rehabilitation of the abridged forms.

§75. <Acknowledgements.—I have had more or less fre-
quent conference or correspondence with nearly all the members
of the four committees named elsewhere (§§80-84) and with
other scientific or literary authorities. Only by investigators,
teachers, and practitioners equally eminent, preoccupied, and fa-
miliar with current terminology, can it be wholly realized what it
meant for these men to give prompt and full attention to que-
ries and propositions that threatened to disturb the verbal basis
of their intercommunications. Reviewing the experience, I am
amazed at the uniform readiness and kindliness of the responses?
and can truly say that even when not wholly or directly encour-
aging they were always fruitful. To four men are due par-
ticular acknowledgements. |

$76. As student (1873-1877), as assistant (1875-1880), as
colleague (since 1880) and as collaborator (‘‘ Anatomical Tech-
nology,’ 1880-1892; ‘‘ Anatomical Terminology,” 1888-1889)
Simon H. Gage has been constantly and preeminently helpful.

§77. Edward C. Spitzka (§80, note) one of the most
learned, progressive and productive American neuro-anatomists,
generously entertained the new terms (’81), adopted some, and
for others proposed improvements; nay, this undaunted up-
holder of an unpopular opinion in a period of intense political

1The last case to meet my eye is Azppos for hippopotami (The Nation), 1896;
verily ‘‘the slang of one age may become the purism of the next.”

?Their nature made it the easier to meet with equanimity the few attempts
to check terminologic progress by ridicule. For the response to one of these
see my paper ’86, f.

Witper, Neural Terms. 237

excitement’ went so far as to say that some of my suggestions
had been long in his own mind but that he had ‘‘lacked the
courage to bring them before his colleagues.’’ Dr. Spitzka’s
cordial interest has never abated, and I only lament that more
practical duties leave him less time now than formerly for re-
search in the anatomy of the brain.

§78. Ihave already expressed (W. & G.,’89, §2 note) my
appreciation of the erudition and kindness of my colleague in
Comparative Philology, Benjamin I. Wheeler. Aside from in-
formation imparted at personal interviews, the etymologic and
linguistic points upon which he has enlightened me cover nearly
one hundred of the ‘‘ correspondence slips.’”

$79. To quote his own words, ‘‘The last thing an old
teacher wants is a new set of terms for a familiar set of objects.”
Yet this did not prevent Oliver Wendell Holmes, then for the
third of a century professor of Anatomy in the Harvard Medi-
cal School, from writing, May 3, 1881, a letter containing the
following passages:

‘«T have read carefully your paper [’81 4] on Nomenclature. I en-
tirely approve it as an attempt. I am struck with the reasonableness
of the system and the fitness of many of the special terms. ‘The plan
is an excellent one; it is a new garment which will fit Science well, if
that capricious and fantastic and old-fashioned dressing lady can only
be induced to try it it on.” The entire letter is printed on pp. 11-12
of (W. & G.,’82). It was asource of comfort tome and doubt-
less led many to consider seriously suggestions that might otherwise
have been ignored or repelled.

Part ITI. Action of the American Neurological Association.

$80. On the 5th of June, 1896, ata regular meeting in
Philadelphia, the American Neurological Association adopted

1As an expert at the trial of Guiteau he held the mental constitution of the
assassin to be abnormal; see Alendst and Neurologést, 1883, April et seq.

*For the use of slips in correspondence see W. and G., ’86, 52 and Sczence,
Jan. 16, 1885, p. 44. Z

238 JOURNAL OF COMPARATIVE NEUROLOGY.

unanimously the ‘‘ Report,of the Committee on Neuronymy.””?
The recommendations were as follows:

1. That the adjectives DORSAL and VENTRAL be employed
in place of posterior and anterior as commonly used in human
anatomy, and in place of wpper and /ower as sometimes used in
comparative anatomy.

2. That the cornua of the spinal cord, and the spinal
nerve-roots, be designated as DORSAL and VENTRAL rather than
as posterior and anterior.

3. That the costiferous vertebrae be called THORACIC rather
than dorsal.

4. That, other things being equal, Mononyms (single-word
terms) be preferred to polyonyms (terms consisting of two or
more words).

5. That the Azppocampus minor be called CALCAR ; the /zp-
pocampus major, HIPPOCAMPUS; the fous Varoliz, pons; the
znsula Retlit, INSULA; pra mater and dura mater, respectively PIA
and DURA.

6. That the following be employed rather than their va-
rious Synonyms: HYPOPHYSIS, EPIPHYSIS (for covarium and cor-
pus pineale), CHIASMA, OBLONGATA, LEMNISCUS, MONTICULUS, TEG-
MENTUM, PULVINAR, FALX, TENTORIUM, THALAMUS, CALLOSUM,
STRIATUM, DENTATUM, MESENCEPHALON, PALLIUM, OLIVA, CLAVA,
OPERCULUM, FISSURA CENTRALIS (for £. Rolando, etc.), F. CALCAR-
INA, F. COLLATERALIS, F. HIPPOCAMPI, CUNEUS, PRAECUNEUS,
CLAUSTRUM, FORNIX, INFUNDIBULUM, VERMIS. :

1 The committee was appointed by the President of the Association, upon
the suggestion of the writer, at the regular meeting in New York city, June 20,
1884. One of the most interested of the original members, Dr. W. R. Birdsall,
has since died. It now comprises Henry H. Donaldson, Ph.D., professor of
Neurology, Chicago University; Landon Carter Gray. M.D., professor of Ner-
vous and Mental Diseases, New York Polyclinic; Charles K. Mills, M.D., pro-
fessor of Diseases of the Mind and Nervous System in the Philadelphia Poly-
clinic; Edward C. Seguin, M.D., professor of Diseases of the Mind and Ner-
vous System in the Medical Department of Columbia University ; Edward C,
Spitzka, M.D., formerly professor of the Anatomy and Physiology of the Ner-
vous System in the Post-graduate Medical School of New York city; and B. G,
Wilder, Chairman.

WitpveER, Neural Terms. 239

$81. Sections 1, 2, 3, and 5 constituted the ‘Preliminary
Report of the Committee on Anatomical Nomenclature”’ of the
Association of American Anatomists which was adopted unani-
mously by that body Dec. 27, 1889."

$82. Section 4 is substantially identical with the second
paragraph of the ‘‘Second Preliminary Report” of the same
Committee,” viz., ‘‘ Your Committee recommend to anatom-
ists that, other things being equal, terms consisting of a single
word each be employed rather than terms consisting of two or
more words.” Proceedings for 1895, p. 4.

$83. Section 4 is also substantially represented in the
‘‘Third Preliminary Report of the Committee on Anatomical
Nomenclature with special reference to the Brain ” * which was
adopted unanimously by the American Association for the Ad-
vancement of Science, Sept. 2, ,1889:— ‘‘ They agree upon
one point, v7z., the advantages, other things being equal, of
mononyms (single-word terms) over polyonyms (terms consist-
ing of two or more words).”” The report was published in
the Proceedings for 1889, p. 26.

Sections I, 2, 3, 5, occur verbatim in the Fourth Report of
the same committee which was adopted unanimously by the
Association Aug. 25, 1890 and printed in the Proceedings, p. 20.

1The members of the committee at that time were Joseph Leidy, M.D.,
L.L.D., professor of Anatomy in the University of Pennsylvania, president ;
Harrison Allen, M.D., formerly professor of Physiology in the U. of P.; Frank
Baker, M.D., professor of Anatomy in the Medical Department of George.
town University ; Thomas B. Stowell, Ph.D., principal of the Potsdam (N. Y.)
Normal School; and B. G. Wilder, Secretary. Tothe committee, at the meet.
ing, was added Thomas Dwight, M. D., professor of Anatomy in the Harvard
Medical School. The report was published in the History and Records of the
Association for 1838, 1889, 1890, p. 5.

2 Upon the death of Dr. Leidy, Dr. Allen succeeded to the chairmanship
of the Committee. The place of Dr. Stowell, resigned on account of pressing
administrative duties, was filled by the appointment of F. H. Gerrish, M.D.,
professor of Anatomy in the Medical School of Maine.

3 The Committee comprised, besides H. Allen, F. Baker, T. B. Stowell,
and B. G. Wilder, chairman (see 381, note), Henry F. Osborn, Sc.D., professor
of Biology in Columbia University.

240 JOURNAL OF CoMPARATIVE NEUROLOGY.

§84. The first five sections of the report of the Neuro-
logical Committee are embodied verbatim in the ‘‘ Preliminary
Contribution of the American Branch of the International
Committee on Biological Nomenclature of the American As-
sociation for the Advancement of Science’’* which was adopted
unanimously by that body Aug. 23, 1892, and published in its
Proceedings, p. 231.”

$85. The report just mentioned is so clear, comprehen-
sive, and concise that its main features are here summarized :

a. ‘Terms relating to position and direction [toponyms,

9] should be intrinsic rather than extrinsic ; that is, should re-
fer to the organism itself rather than to the external world.”

6. ‘So far as possible terms should be single, designa-
tory words [mononyms, $15] rather than descriptive phrases.”

c. Terms derived from the names of persons [eponyms,
§33] should be avoided.

dé. ‘*Each term should have a Latin [international, $46]
form.”’

e. ‘Each term should have also a [national, §43] form in
accordance with the genius of each modern language, e. g.,
a paronym [$44] of the original Latin form.”

jf. The report gives due recognition of the labors of other
committees and of individuals.

$86. Returning to the report adopted by the American
Neurological Association [$8o0| its recommendations may be in-
dicated conveniently in the following Table I: ;

1 The members are George L. Goodale, Ph.D., professor of Natural His-
tory in Harvard University, chairman ; John M. Coulter, L.L.D., president of
the State University of Indiana; Theodore Gill, Ph.D., Smithsonian Institution;
Charles Sedgwick Minot, Ph.D., professor of Embryology in Harvard Univer-
sity; Simon H. Gage, B.S., professor of Histology and Embryology in Cornell
University, secretary.

2 Reprints were distributed to biologists of all nationalities and may be ob-
ained from the secretary.

Wiper, Weural Terms. 241

TABLE I.

Forty Latin names recommended unanimously by the American Neurolog-
ical Association, June 5, 1896.

Mononyms (stngle-word terms) Dionyms
CALCAR HIPPOCAMPUS PIA CORNU DORSALE
CALLOSUM HypopHysis PoNs CORNU VENTRALE
CHIASMA INFUNDIBULUM PRAECUNEUS |FISSURA CALCARINA
CLAUSTRUM |INSULA ; PULVINAR FISSURA CENTRALIS
CLAVA LEMNISCUS STRIATUM FISSURA COLLATERALIS
CUNEUS MESENCEPHALON TEGMENTUM |FISSURA HIPPOCAMPI
DENTATUM |MONTICULUS TENTORIUM |RADIX DORSALIS
DURA OBILONGATA THALAMUS’ |RADIX VENTRALIS
EPIPHyYsIS OLIVA VERMIS VERTEBRA THORACALIS
FALX OPERCULUM
FORNIX PALLIUM

$87. Cerebellum might well have been added to the list
for there is no disagreement as to the application of the word.
Cerebrum, unfortunately, is used in at least two senses, (a) as
equivalent to the prosencephal, and (4) as including also two or
three adjoining segments.

$88. Of the forty terms in the above list thirty-one are
mononyms (S15). The other nine, nearly one-fourth, are dio-
nyms ($13). This fact is to be noted in connection with cer-
tain animadversions of the German committee (Part V).

$89. In Table II are given in parallel columns (1) the
Latin (international) names adopted by the American Neuro-
logical Association ; (2) their English paronyms; (3) the regu-
lar Latin adjectives; (4) the English forms or paronyms of
the Latin adjectives.’

1 Had space permitted I should have been glad to amplify this table after
the pattern of that upon pp 530 and 531 of W.&G., ’89. Forty-five terms
were there given substantially as in the following example:

LATIN
(Common polyonym in upper line.)
Nom. singular | Genitive | Nom. plural | Adjective
Thalamus nervt optict

Thalamus | Zhalamt | Thalami | Thalamicus
ENGLISH
(Heteronym in upper line.)
FRENCH
Singular Plural Adjective GERMAN
ITALIAN
Optic bed
Thalame
THALAMUS | THALAMI | THALAMIC Thalamus
Talamo

242

TABLE If.

JOURNAL OF COMPARATIVE NEUROLOGY.

Derivatives of the Terms adopted by the American Neurological Association.

Sudbstantives Adjectives
Latin English Latin English
1|Calcar Calcar Calcarinus Calcarine
2)|Callosum Callosum Callosalis | Callosal
3)Chiasma Chiasma or chiasm Chiasmaticus Chiasmatic
4|Claustrum Claustrum Claustralis Claustral
5|Clava Clava Clavalis Claval
6!Cornu dorsale —_|Dorsal cornu
7|Cornu ventrale |Ventral cornu
8}Cuneus Cuneus Cunealis Cuneal
g|Dentatum Dentatum Dentatalis Dentatal
10|Dura Dura Duralis Dural
11|Epiphysis Epiphysis Epiphysialis Epiphysial
12|Falx alx Falcialis Falcial
13|F. calcarina Calcarine fissure
14|F. centralis Central fissure
15|F. collateralis |Collateral fissure
16/F. hippocampi |Hippocampal fissure
17|Fornix Fornix Fornicalis Fornical
18|Hippocampus !Hippocamp or hippo-|Hippocampi (gen.)|/Hippocampal
campus or hippocampalis
19|Hypophysis Hypophysis Hypophysialis Hypophysial
20|Infundibulum = _|Infundibulum Infundibularis Infundibular
21\Insula Insula Insularis Insular
22|Lemniscus Lemniscus Lemniscalis Lemniscal
23|Mesencephalon |Mesencephal or mesen-|Mesencephalicvs |Mesencephalic
cephalon
24|Monticulus Monticulus Monticularis Monticular
25|Oblongata Oblongata Oblongatalis Oblongatal
26|Oliva Oliva or olive Olivaris Olivary
27\|Operculum Operculum or opercle |Opercularis Opercular
28} Pallium Pallium Pallialis Pallial
29|Pia Pia Pialis Pial
30| Pons Pons Pontilis Pontile
31\Praecuneus Precuneus Praecunealis Precuneal
32|Pulvinar Pulvinar Pulvinaris Pulvinar
33) Striatum Striatum Striatalis Striatal
34|Tegmentum Tegmentum or tegment|Tegmentalis Tegmental ~
35\Tentorium Tentorium Tentorialis Tentorial
36|Thalamus Thalamus Thalamicus Thalamic
37|Radix dorsalis |Dorsal root
38|Radix ventralis |Ventral root
39| Vermis Vermis Vermianus Vermian
40|Vertebra_ thora-/Thoracic vertebra

calis

WILpvER, Neural Terms. 243

§go. It should be borne in mind that only the Latin
names in the first column have the sanction of the various As-
sociations that have adopted them. The derivatives and the
comments thereon do not constitute parts of the reports. In-
deed, as will be seen, there is room for considerable latitude of
opinion and usage; my own views may be imperfect and even
inconsistent, but I think the analogies adduced are sound.

S91. English Plurals.—The parts of the brain are so sel-
dom named in the plural that a separate column is not given there-
for. Analogy with crises, strata, fungi, algae and phonomena would
justify the employment of the regular Latin plural in certain
cases, e. g., thalami, epiphyses, hippocampi, cornua, striata and
vertebrae. On the other hand, aveas, vistas, hernias, emporiums,
lenses, geniuses, pianos, indexes, pericarps, angles, atlases, dt-
plomas, and similes are precedents for calcars, chiasmas (or
chiasms), falxes, lippocamps, insulas, mesencephals, ponses, ver-
mises. Bonuses would even justify thalamuses but the length of
the latter is objectionable.

$92. Close resemblance of the Angloparonyms to the Latin
originals.—This is so obvious as to hardly require mention.
With more than half, the two forms are identical in spelling, fe)
that the Latinity of the originals can only be indicated to the
eye by italics, and to the ear by the pronunciation now com-
monly adopted for Latin words.'

§93. Hippocamp.—For this, as the Angloparonym of
hippocampus, there are many precedents, notably the follow-
ing:—antepenult, digit, tmpediment, diagram, telegram (which was
strenuously objected to when first introduced), epzcarp and perr-
carp ; see my note as to peszcard, ’95, a.

S94. Infundibulum.—lf the part so designated were fre-
quently mentioned it is probable that either a shorter word
would be found,or the present name be paronymized as z7fundt-

1 The Angloparonyms of Latin words, even when orthographically unmod-
ified, are Eaglish by adoption and are to be so pronounced; to pronounce ¢c/aus-
trum, clowstroom in an English sentence would beas affectedas to say mamorarn-
doom. As an English word od/ongata has the first a as in mate.

244 JOURNAL OF COMPARATIVE NEUROLOGY.

bule, after the analogy of vetucule, dwerticle, etc. The same may
be said of smonticulus and monticule; see $167.

$95. Mesencephalon.—By itself and used occasionally the
. Latin form is certainly euphonious and unobjectionable ; but in
any discussion of the segmental constitution of the brain,
whether written or spoken, the frequent recurrence of the ob-
trusively Latin termination is pedantic and burdensome. Its
omission is warranted by words like angel.'

S96. Operculum and Opercle.—The Latin tetrasyllable is
not commonly oppressive, but the compounds preoperculum etc.,
might well become so. The case is comparable with that of
ultima ; with it, and even with penxultima, the last two syllables
are endured; but when two more syllables are added at one end,
then two are dropped from the other, leaving antepenult of only
moderate length.. Preopercle, subopercle and postopercle are
already applied to analogous parts of the fish’s head; see
$$67-70.

$97. Praecuneus.—Here the difference between the Latin
antecedent and the Angloparonym consists in the replacement
of the ae by e¢ as in preposition, pretext, preface, etc.

S98. Zentorium.—By analogy with ovary, aviary, granary,
laboratory etc., the Angloparonym would be éentory, and this
word has been used to designate the awning of atent. But
tentorium is unobjectionable and likely to be retained as an un-
changed paronym.

S99. ontilis.—Unwarrantable forms of the English ad-
jective from pons occur so frequently that there is here repro-
duced a paragraph from my recent note on the subject, ’96, a.
‘‘In the subtitle of the letter above mentioned the case is re-
ferred to as one of ‘pontine hemorrhage.’ This form of the
adjective is not uncommon in medical literature, and pontic and
pontal have found their way into the dictionaries.. Now, as may
be seen from any Latin lexicon, fovtal has no justification what-
ever. /onticus, the Latin antecedent of foviic, is derived from
pontus, the sea. Pontinus, the antecedent of pontine, was orig-

' Respecting the possibility of further abridgement of these terms see 274.

WILDER, Neural Terms. 245

inally Pomptinus, and refers to a district of Italy. As already
pointed out by me (article Anatomical Terminology, Buck's
Reference Handbook of the Medical Sciences, VIII, 524, $50),
the only legitimate Latin adjective from fozs is pontilts, and its
Angloparonym is pontile. The use of any other form tends
to cause confusion and to bring discredit upon medical
scholarship.”

Part IV. Comparison of the Terms Adopted by the American
Neurological Association with those Adopted by the Anat-
omische Gesellschaft.

§roo. Inthe accompanying Table III are given in par-
allel columns (1) the forty terms adopted by the A. N. A.; (2)
the corresponding terms adopted by the Anatomische Gesell-
schaft ; (3) some of the Latin synonyms.

§1o1. Probably few will question the inferiority of the
discarded synonyms in the third column; hence are here con-
sidered mainly the relative merits of the two other sets.

$102. The extent of agreement is impressive and en-
couraging. With the following twenty-four terms there is abso-
lute consensus between the American and the German commit-
tees: Claustrum; Clava; Cuneus; Fissura calcarina; F. collat-
eralis; F. hippocampi; Fornix; Hippocampus; Hypophysis ;
Infundibulum ; Insula; Lemniscus ; Mesencephalon ; Monticu-
lus; Oliva; Operculum ;' Pallium; Pons; Praecuneus; Pulvi-
nar; Tegmentum; Thalamus; Vermis; Vertebra thoracalis.

$103. With the following ten terms the differences lie
merely in the retention by the Germans of certain words which
the Americans regard as superfluous. In the following list these
words are italicized: Calcar avs ($105); Corpus callosum ($111);

1 The case of this term is peculiar. The German committee particularize
three parts, frontal, partetal and temporal of a general operculum. The Neuro-
logical Association regards the parietal portion as ¢#e operculum, the frontal and
temporal being so specified. (By the present writer these are designated as
pracoperculum and postoperculum, and the orbztal portion as suboperculum.) It will
be seen therefore that while the word ofercu/um is identical with both commit-
tees, its significance is general with the German and special with the American.

246 JOURNAL OF COMPARATIVE NEUROLOGY.

TABLE III.

Comparison of the Terms adopted by the American Neurological Associa-
tion (first column) with those of the German Committee (second column) and
with certain Synonyms (third column).

I|}\CALCAR

2|/CALLOSUM
CHIASMA

3
4|CLAUSTRUM
5|CLAVA

6|CORNU DORSALE
7|\CORNU VENTRALE
8|CUNEUS

9| DENTATUM
Io/DURA
11) EPIPHYSIS

12|FALXx
13|FISSURA CALCARINA
14| FISSURA CENTRALIS

15 FISSURA COLLATERALIS

16|FISSURA HIPPOCAMPI

17| FORNIX
18} HIPPOCAMPUS

19] HYPOPHYSIS

20| INFUNDIBULUM
21|/INSULA

22| LEMNISCUS

23] MESENCEPHALON
24) MONTICULUS
25|OBLONGATA
26/OLIVA
27|OPERCULUM

28) PALLIUM
29|PIA
30| Pons

31] PRAECUNEUS
32| PULVINAR
33|STRIATUM
34|TEGMENTUM
35|TENTORIUM
36/THALAMUS

37) RADIX DORSALIS
38] RADIX VENTRALIS
39| VERMIS

Calcar avis

Corpus callosum
Chiasma opticum

Claustrum

Clava

Columna posterior
Columna anterior
Cuneus

Nucleus dentatus
Dura mater
Corpus pineale

Falx cerebri
Fissura calcarina
Sulcus centralis

Fissura collateralis

Fissura hippocampi
Fornix
Hippocampus

Hypophysis

Infundibulum
Insula

Lemniscus

Mesencephalon

Monticulus

Medulla oblongata

Oliva

Operculum (pars par-
ietalis)

Pallium

Pia mater

Pons [Varolii]

Praecuneus
Pulvinar

Corpus striatum
Tegmentum
Tentorium cerebelli
Thalamus

Radix posterior
Radix anterior
Vermis

40' VERTEBRA THORACALIS! Vertebra thoracalis

Hippocampus minor; Eminentia
digitalis; Unguis

Corpus callosum; Trabs cerebri

Chiasma nervorum opticorum;
Commissura optica

Claustrum

Processus clavatus

Cornu posterius

Cornu anterius

Lobulus occipitalis internus; Lob-
ulus cuneatus

Corpus dentatum cerebelli

Dura mater

Conarium; Glandula pinealis ;
Epiphysis cerebri

Falx major; Processus falciformis

Fissura occipitalis horizontalis

Fissura Rolandica; S. postero-
parietalis
Sulcus occipito-temporalis; 5S.

temporo-occipitalis

Fissura hippocampi

Fornix tricuspidalis

Hippocampus major; Cornu Am-
monis

Glandula pituitaria ; Hypophysis
cerebri

Pedunculus hypophyseos

Insula Reilli; Lobus centralis ;
Median lobe

Laqueus

Mesencephalon

Monticulus

Bulbus rhachidicus

Corpus olivare ; Nucleus olivaris

Operculum parietale

Mantellum
Pia mater
Pons Varolii ;
nularis
Lobus quadrilaterus
Tuberculum [thalami] posterius
Ganglion cerebri anterius
Tegmentum caudicis
Tentorium
Thalamus opticus; T. nervi optici;
Ganglion cerebri posterius
Radix posterior
Radix anterior
Vermis bombycinus;
vermiformis
Vertebra dorsalis

Protuberantia an-

Processus

Witper, Neural Terms. 247

Chiasma opticum (§109) ; Wucleus dentatus (§123); Dura mater
($116); Falx cerebri ($124); Medulla oblongata (§116); Pia
mater ($117); Corpus striatum (§115); Tentorium cerebelli
($125).

$104. With the remaining six terms the differences are
more or less radical (S$119-122, 127-133).

§105. CALCAR versus calcar avis. ‘Thirty years ago,
in connection with the controversy as to the cerebral , peculiari-
ties of man, the term /zppocampus minor became familiar even
to general readers. Nevertheless, probably influenced in some
degree by Huxley’s proposition to replace Owen’s posthippo-
campal and Henle’s occipitals horizontalis by calcarina,' anatom-
ists have been more and more generally employing calcar avts,
and this is adopted by the German committee in preference also
to uuguis and eminentia digitalis. The advantages of correlated
names ($32) for collocated parts are many and great, as illus-
trated by Aippocampus [major] and fissura hippocampi; by emt-
nentia collaterals and fissura collaterals. In the present case
these advantages would have been gained equally had Huxley
adopted Owen’s fosthippocampal for the fissure and proposed
posthippocampus for the ental ridge corresponding thereto. In-
deed this would have been in accordance with the general prin-
ciple of locative names (§29) and learners would have been
spared thereby some effort of memory. In this, however, as
in so many other instances it is now idle to speculate upon the
consequences of harmonious cooperation between the two lead-
ers of English anatomy at that period. Assuming that calcar
avis has general and decided preference over the other names
enumerated, there need be stated here only the grounds upon
which calcar has been unanimously adopted by four American
Committees and by the three associations which they represent.

§106. Briefly, the adoption of calcar is a logical corollary
of the recommendation which is common to the reports of all

1Pye-Smith wrote as follows nearly twenty years ago (’77): ‘‘Of all the syn-
onyms of hippocampus minor, calcar avis is the most distinctive and brings it at
once into relation with the calcarine fissure.”

248 JOURNAL OF COMPARATIVE NEUKOLOGY.

four American committees, viz., ‘‘Other things being equal,
it is recommended that mononyms be preferred to polyonyms.”’
Calcar avis is a polyonym ; ca/car is a mononym.

If it be said that wxguzs is also a mononym, the answer is
that in this case ‘‘other things”’ would not be equal, because
(1) no general preference has ever been shown for it or for any
term of which it is a constituent; (2) there would be lost the
advantage of the correlation now existing between the ental
ridge and the fissure collocated therewith.

§107. Two objections might be offered to the omission of
the qualifying genitive, avzs.

1. The original sense of the Latin calcar was spur, and
its application to the sharp projection on the leg of the cock
was metaphoric. This can hardly be entertained as a serious
objection; indeed, although the modern spur has a toothed
wheel or rowel, the primitive instrument was little more than a
spike; hence the qualifying genitive is needless.

2. Calcar has also been applied occasionally to two other
parts, viz., the calcaneum (os calcis) and the styloid process of
the temporal bone. But, (a) neither of these uses is sanctioned
by the German committee, and (0) even if they were, the con-
text would infallibly avert misapprehension ($§23, 67); indeed,
the German committee apply c/vus without qualification to fea-
tures of two adjacent cranial bones, the occipital and sphe-
noidal.

$108. Finally, the sufficiency of the mononymic substan-
tive, calcar, is practically conceded by all who employ the mon-
onymic adjective, calcariuus, in any of its Latin inflections, or
in any of its national paronymic forms. The simplest require-
ments of logic present the following dilemma: If calcarinus is
sufficiently distinctive, so is calcar from which it is derived.
But if calcar avis is essential, then the adjective should be cal
cart-avianus or some such compound. See also under dura
(115). There seems to have been little if any hesitation on the
part of the German committee in adopting /fissuva calcarina
(His, ’95, 170) and no reason for the maintenance of calcar avis
has yet come under my notice.

WiLverR, Neural Terms. 249

S1o9g. CHIASMA vs. Chiasma opticum.—Meynert’s chi-
asma nervi acustict is not retained by the German committee,
and even if it were there is no likelihood of confusion with it
or with Camper’s chiasma tendinum. The chiasma is and always
will be that of the optic nerves. The use of any qual-
ifier suggests undesirable variations like chiasma nervorum optic-
orum and commussura optica. Furthermore, the sufficiency of
the unincumbered mononym is practically conceded by the Ger-
man committee in designating one of the subarachnoid spaces
as cisterna cliasmatis; see also His, ’95, 171, line 8’.

S110. ZTHALAMUS.—This term may naturally be men-
tioned here. In the German list the adjective ofticus is omitted,
and His makes the following remark ('95, 7, lines 1-3): ‘‘Wir
stimmen unsererseits vollig bei, wenn das Wort Thalamus kurz-
weg an die Stelle von Thalamus opticus gesetzt wird.’”’ But it is
worthy of note that ¢a/amus is strictly'an idionym (§24), and
that the only valid excuse for the addition of the adjective is a
desire to aid the student’s memory by the association with the
optic nerve. Asa matter of fact, no case of real advantage is
known to me, and the frequent repetition of the adjective may
easily become a burden, as pointed out by me in 1888 ('88, 8).

S111. CALLOSUM vs. corpus callosum.—Corpus callosum
is the most familiar type of a large group of anatomic names. In
1889, including unusual synonyms, I recorded one hundred
neural polyonyms of which corvpus constituted the initial word.
Ten such remain upon the German list, (viz., corpus restiforme ;
cp. trapezoideum ; cp. medullare ; cp. quadrigeminum ; cp. mamil-
lare; cp. gentculatum mediale ; cp. gnc. laterale; cp. pineale ; cp.
callosum ; cp. striatum), and their genitives are correspondingly
in evidence.

§112. It must be admitted that corpus callosum is rather
attractively sonorous. It is easily pronounced and even, like
quadrupedante, ‘‘runs trippingly from the tongue.’ But that is

} The word chzasma is discussed at some length by Hyrtl, ’80, 105-106.

? A similar concession has been made (Sczence, June, 22, 1888, editorial) to
the claims of proper names like Johnny McWhorter which are euphonious and
easily remembered.

250 JOURNAL OF COMPARATIVE NEUROLOGY.

no reason for the retention of a word which is not merely need-
less, but really burdensome by reason of the frequency with
which certain parts are mentioned. In one short paper (Srazn,
’ October, 1885, 377-379) corpus callosum occurs twenty times,
an average of once in five lines; corpus occupies 2.5 lines, one-
fortieth of the entire paper.

§113. The elimination of corpus from all neural names
constituted one of the fundamental propositions of my first
communication upon the general subject (80, 7), and since that
time it has been consistently practised and persistently preached.

§114. By the use of the genitive case, corporis callost,
the German committee have designated the various divisions of
the callosum, (splenium, genu, truncus and rostrum) ; also the
sulcus along its dorsal margin. They have thus avoided the
use of the secondary adjective cal/losals. But in expressly re-
jecting pedunculus corporis callost in favor of gyrus subcallosus
(His, ’95, 170-172) they practically concede the superfluity of
the corpus.

§115. Unless we are prepared to abandon all adjective-
substantives (§118) there seems to be no reason for the further
retention of corpus in any of the terms enumerated in §111.
Corpus fornicis of the German list is not open to the objection
that naturally arises against corpus corporis callost but truncus
corpus callosi is a good precedent for truncus fornicis if the
distinction be necessary.

§116. DURA vs. dura mater.—This constitutes a type
and test case for a considerable group of anatomic terms from
which, for fifteen years, I have dropped the (here italicized)
nouns, viz., pia mater; substantia alba; substantia cinerea;
membrana (or tunica) serosa ; mb. (or tz.) mucosa; mb. (or tn.)
submucosa; md. (or tz.) arachnoidea; medulla oblongata. From
the group of ‘‘corpus”’ polyonyms they differ in that the elim-
ination of the substantive leaves a feminine instead of a neuter
adjective to be used substantively, and as a base for the forma-
tion of secondary adjectives, dural, mucosal, cinereal, arach-
noidal, ete.

§117. Curiously enough the first precedent for this known

WILpER, Veural Terms. 251

to me dates back a hundred and fifty years. Inthe ‘‘ Medical
Dictionary” of James (1743), in the article ‘‘cerebrum’”’, occurs
the following sentence: ‘‘The superficial vessels of the cerebrum
are lodged’ between the two laminae of the pia.”

§118. The employment of the mononymic feminine ad-
jectives as substantives, and of the secondary adjectives de-
rived therefrom, has now become so general! that the matter
would hardly need discussion but for the reactionary attitude of
the German committee. Yet this attitude is really not main-
tained consistently. Cornea is a feminine adjective. So is sclera.
In arachnoidea encephah the feminine adjective is used as a noun.
Muscularis mucosae and tela submucosa are warrants for mucosa,
etc. Finally, although the useless noun is retained in dura
mater spinalis and filum durae matris spinalis, the very next
terms in their list, cavum epidurale and cavum subdurale, are indi-
rect and probably unintended, yet none the less complete, pre-
cedents for duva pure and simple, and for the substantive em-
ployment of any and all feminine adjectives whatsoever.

§1i9. EPIPHYSIS vs. corpus pineale.—His regards epiph-
ysisas a ‘‘generelles Wort” (’95, 163) and theancient dionym
is adopted by the Germancommittee.?- My own earlier preference
was for conarzum, as stated in §68. I now realize the desirabil-
ity of the verbal as well as the topographic correlation with
hypophysis and paraphysis, and the inutility of maintaining in all
cases the rigid doctrine of 1871 (§67).

§120. FISSURA CENTRALIS vs. sulcus centrals (or
fissura or sulcus Rolando).—By comparison of the three columns
it will be seen that two distinct points are concerned, involving
respectively the generic and the specific names of this feature of
the lateral aspect of the cerebrum. If eponyms or personal
names are to be abandoned, as decided by the German commit-

1 In Foster’s Medical Dictionary, dura and fia, dural and pial, are major
headings, dura mater and pia mater being merely synonyms.

2 In the earlier publication (Scéence, July 17, 1896, p. 71) of the report of
the Neurological Committee, the date, 7895, after epiphysis would indicate its
adoption by the Germans. That was an error for which I must be held respon-.
sible, and which was corrected as soon as possible after it was noted; ’96, 4.

252 JOURNAL OF COMPARATIVE NEUROLOGY.

tee and as advocated by me, since 1880,’ then all the derivatives
of Rolando must be discarded in favor of cextralis and its deriva-
tives. Those who prefer the eponym should show that Rolando’s
- figure and description really merit such commemoration, and
should be also at least‘consistent in the employment of deriva-
tives. Paracentralis, praccentralis and postcentralis have no other
justification than topographic reference to cextralis; yet itis by
no means uncommon to find in oneand the same paper ‘‘fissure
of Rolando” and ‘‘paracentral lobule.”’

§121. As tothe generic terms, fissuva and sulcus, the
former has been consistently employed by me since 1880 for all
linear depressions of the} cerebral surface, while the German
committee restrict it to the sylvian (called by them cevebri lat-
evalis), the collateral, the occipital (their parieto-occipitalis) the
calcarine and the hippocampal, and name all the others sadcz.
They regard the striatum as constituting an ental correlative of
the sylvian (p. 170); hence it may be inferred that fisswra indi-
cates a corrugation of the entire parietes, while sz/cws indicates a
linear furrow not represented in the cavity by a corresponding
elevation.” Fully conceding the desirability of recognizing the
distinction between the two groups of cerebral furrows, the fol-
lowing considerations lead me to question the advisability of
employing the two generic words in the senses proposed by the
German committee.

(1). /2ssura and its various paronyms and heteronyms are
already well established and commonly associated with cerebral
topography. This subject, on account of its various relations,
physiologic, pathologic, surgical and psychologic, has already
gained much general interest. Sw/cus is a comparatively unfa-
miliar word. It is distinctively Latin and technical. . Its Latin
plural, sz/cz, is even more so. It does not readily lend itself to

‘ With the exception of fissura Sy/vii and certain derivatives of sy/véana,

*The two groups are sometimes distinguished as ¢ofal and partial, or as complete
and zxcomplete. The former seem to be preferable, since with the total the to-
tality of the parietes is involved, whereas complete and incomplete seem to im-
ply differing degrees of relative perfection.

WILvER, WVeural Terms. 253

paronymization, sw/c and szulcuses being both somewhat un-
acceptable.

(2). Sulcus has recently been employed by Mrs. Gage
(93), O. D. Humphrey (’94), P. A. Fish ('94), and B. F. Kings-
bury (95), for ental (entocelian or intraventricular) depressions
which are less likely than the cerebral furrows to become sub-
jects of general interest.

$122, (3). There isa practical difficulty that cannot be
ignored. Nothing in the words fssura and sulcus, or in their
ordinary associations, serves to admonish us as to the proposed
distinction. Hence there is liability to misuse and confusion.
Many actual instances of this might be cited but the following
may suffice. Edinger (’95) apparently intends to apply fissura
to the total fissures, and the occipital is so designated in the in-
dex; but on Fig. 33 it is called sadcus. Kolliker (‘‘Entwickel-
ungsgeschichte,”” p. 555) attributes salcus calcarinus to Huxley,
who uses fissure as does Kolliker in the explanation of a figure.
Flower (‘‘Proteles,”” Zool. Soc. Proc., 1869) applies to the supra-
orbital, fissura and sulcus indifferently. Huxley (‘‘ Vertebrated
Animals’) says that the cerebral surface becomes complicated
by ridges and furrows ‘‘the gyri and sulci;” but the first of
the ‘‘sulci’’ to be mentioned is the ‘‘ sylvian fissure”’ and the
second ‘‘the fissure of Rolando,” the latter also being desig-
nated on Fig. 21 asthe ‘‘sulcus of Rolando.” Flower and
Lydekker (Mammals, p. 71) say ‘‘the sylvian fissure is one of
the most constant of the sulci. In the last two cases the gen-
eric designation of the shallower furrows is made to include
both kinds, and curiously enough this usage is apparently sanc-
tioned by the German committee in introducing gyvz cerebri and
sulct cerebrt as comprehensive names and then specifying certain
Sulcisand fissurae -seeulable VIL. IL -10;)07;/(26:

§123. DENTATUM vs. Nucleus dentatus.—Two separate
questions are involved in the choice between these terms: (a)
The use of xucleus (with a masculine adjective) in place of
corpus (with a neuter) ; (4) The employment of an adjective of
either gender as a substantive. The latter is considered in con-
nection with collosum and dura (§S11t-118). The substitution of

254 JOURNAL OF COMPARATIVE NEUROLOGY.

nucleus for corpus seems to the American committee to consti-
tute a step backward, as tending to obscure the commonly ac-
cepted distinction between the part in question, with the analo-
gous part in the oliva on the one hand, and the ‘‘nuclei’”? of ori-
gin of the various nerves on the other.

$124. FALX vs. Falx cerelxi.—The German committee
designate the slighter fold of dura between the two lateral masses
of the cerebellum as falr cerebelli. The present writer prefers
the diminutive, falcula. The American committee has not yet
passed upon this case. Even should they retain falr cerebelli it
would not prove a serious burden, because the part is hardly
mentioned once while the cerebral septum is named ten times.

$125. ZENTORIUM vs. tentorium cerebell.—This case is
even stronger than that of falx, for tentorium is an idionym (§24).

§126. SZTRIATUM vs. Corpus striatum.—See callosum,
(S111).

$127. CORNU DORSALEvs. columna ( grisea) postertor.
—Two distinct issues are involved here: (a) toponymic, be-
tween foster zor and dorsalis; (6) organonymic, between colwmna
and cornu. The former will be considered in connection with
cornu ventrale ($131) and radix dorsalis (§132).

§128. CORNU vs. columna.—lIt is almost embarassing to
find myself advocating the maintenance of ancient and general
usage against one comparatively novel. Probably most ana-
tomic teachers will sympathize with the German committee in
their objection to the application of cornu to what is really one
of several ridges of a deeply fluted column of gray nervous tis-
sue constituting the core of the ‘‘ spinal cord;’ ridges that re-
semble ‘‘horns”’ only when artificially exposed upon transec-
tion. At least ten years ago I was so deeply impressed by this
inappropriateness of cornu as to hunt up an architectural term,
namely avrzs, signifying the ridge between two adjoining chan-
nels of a Doric column. Whether or not it was derived from
arista, it is excellent Latin in form, and acceptable in every re-
spect save its novelty.

1 The question of preference between mucleus, and nidus (Spitzka) and nidu-
/us (C. L. Herrick), need not be considered upon the present occasion.

Wiper, Neural Terms. 255

§129. Yet I believe that I did well to refrain from its in-
troduction ; for, after all , in nine cases out of ten, the artificial
appearance presented upon section is what is first offered the
student, and I have never known a case of misapprehension
occasioned thereby. Upon the whole, this has seemed to the
American committee a good case for the observance of Huxley’s
aphorism (80, 16) as to the unadvisability of interfering with
terms that are well established and have a definite connotation,
even when they may be etymologically inadequate, e. g., cadlo-
sum. Individually, I should feel that the case against cornu
would be much stronger were it a word of half a dozen sylla-
bles, or lacking in euphony.

§130. The assignment of co/umna to the ridges of the myelic
cinerea naturally involved the replacement of that word, as com-
monly applied to the intervening masses of alba, by some other
word ; the German committee selected fumzculus. If cornu be
retained, columna will be available as hitherto. Even if a change
be made, however, why not /uzzs instead of the longer diminu-
tive, upon the grounds stated in $21? There could hardly be
confusion with the same word as applied to the ‘‘ umbilical
cord.”

§131. CORNU VENTRALE.—As an objection to this
term it might be urged that consistency would involve the ap-
plication of the same words to the ‘‘ middle” or ‘“ descending”
extension of the ‘‘lateral ventricle,’ which the German com-
mittee call cornu infertus. What the American committee may
do in this connection remains to be seen. There would be no
real cause for ambiguity, however, since cornu temporale, c.
Jrontale, and c. occipitale are perfect examples of a class of
terms that suggest parts or regions already familiar. Personally
I have never had any difficulty, the locative, mononymic,
idionyms (§$25, 27) medicornu, praecornu and postcornu, having
been consistently employed by me for fifteen years (’81, J. d).

§132. RADIX DORSALIS vs. radix posterior.—Since,
with this and with vadix ventralis (or anterior) the Americans
and the Germans are at one as to the substantive element, there
only recurs the toponymic difference already alluded to in con-

256 JoURNAL OF COMPARATIVE NEUROLOGY.

nection with the ridges of the myelic cinerea (§127). The differ-
ence is far reaching and literally radical. As with the myelic
sulci, columns, cornua and commissures, the folds of the axilla,
the aspects of the thigh, the tubercles of the cervical vertebrae,
the sides of the stomach and other viscera, the valves of the
heart, there is exemplified one of the most undesirable features
of the pernicious influence of anthropotomy upon anatomy at
large.*

§133. Upon this subject the position of the German com-
mittee in 1895 is indicated by the following translation of pass-
ages from His, (’95, 109-110): ‘‘ As mentioned above, Herr
von Kolliker has proposed replacing generally the words anterior
and posterior by ventralis and dorsalis where the relations to
comparative anatomy, and especially to the anatomy of domes-
ticated animals, render it desirable; that is, where the terms
anterior and postertor apply only to the upright attitude of man.
* * * We do not deny the merit of such strict usage, but
the commission has not been able to decide upon its adoption.
It involves all kinds of difficulties and inconveniences. * * *
We leave time to determine whether or not we shall depart from
the traditional usage associated with the erect attitude of man.”

Had most of the members of the commission been investi-
gators and teachers of zootomy rather than of anthropotomy,
there would probably have been no hesitation in adopting terms
that apply equally well to all vertebrates in any attitude. Let
us hope that the distinguished President of the Commission
may live to see his recommendations unanimously adopted.-

$134. I close this discussion of the differences between
the recommendations of the American and German committees
with the remark that, strictly speaking, not one of the words
in the first column of Table III can be imputed to us. All
were in use for longer or shorter periods prior to 1880. Com-

1 «The influence of the nomenclature of human anatomy, reflected down-
ward upon the dawning structures of the lower animals which culminate in
man, is nowhere more obstructive to a plain and true indication of the nature
of parts than in regard to those of the brain.” Owen, ’61, I, 294, note.

Wiper, WVeural Terms. 257

parison with the second and third columns will show that in
most cases our office was merely to disencumber the essential
elements of prexisting terms from superfluous accessories.

Part V. Reply to the Criticisms offered by the Anatomische
Gesellschaft or its Members upon the Terminologic Propost-
tions or Usage of American Committees or Individuals.

§135. Inthe introduction to this article (§3) it is inti-
mated that certain ‘‘ German declarations against the efforts of
the American committees may be due in part to ignorance or
How far these mental condi-

”

misapprehension of the facts.
tions might have been avoided may be judged from the follow-
ing statements.

§136. As mentioned in Part II, even if my earlier formu-
lation of principles and specific suggestions (1871-1879) be dis-
regarded, in and after 1880 papers referring directly to anatomic
or neurologic nomenclature were published in periodicals pre-
sumably accessible to anatomists everywhere.’ The appoint-
ments of the committees of the American Neurological Associ-
ation and of the American Association for the Advancement of
Science (§$§80-84) were duly announced in medical and scientific
journals, and in the transactions of the two associations. A
brief preliminary report of the A. A. A. S. committee was
printed in the Proceedings of the Association for 1886 (p. 56).

§137. The ‘‘Nomenclatur Commission” of the Anatom-
ische Gesellschaft was appointed in 1889. Primarily German
(His, ’95, 3), additions were made in the following year from
England, France and Italy. According to His (’95, 6, 7) co-
Operation was also asked from Thane, Duval and Testut. A\l-
though the Anatomische Gesellschaft contains some American

To what extent reprints of those papers were sent to German anatomists
at that time, I'am unable to determine.

2 Its final composition was as follows: A. von Kdlliker, president; O. Hert-
wig, W. His, Kollman, Merkel, Schwalbe, Toldt, Waldeyer, Bardeleben, Henke,
von Mihalkovics, Riidinger, von Kupffer, Turner, Cunningham, Leboucgq,
Romiti, and W. Krause, secretary. This list was furnished me by the
secretary in April, 1892.

258 JoURNAL OF COMPARATIVE NEUROLOGY.

associates, none, so far as I know, was invited to serve on the
committee. Ifthe omission was remarked by others, they prob-
ably, like myself, attributed it to the geographic interval.

§138. In the fall or winter of 1890 I received from the
secretary, Prof. W. Krause, a letter (since mislaid) reading
substantially as follows: ‘‘I have an idea that something as to
Anatomical Nomenclature has been done in America. Please
to send me copies of Reports and other documents.”’

$139. In response there were promptly sent copies of all
the Preliminary Reports together with my papers and lists up
to date. Their receipt was acknowledged by Dr. Krause Dec.
2g9th., 1890, and later in the following :

Gottingen, Apr., 15, 1891.
Dear Mr. Wilder :

I have received your papers with many thanks; if possible
please to send me some ten further copies of your two pages on polyo-
nyms, heteronyms etc., of the brain; [‘* Handbook,” VIII, 530, 531].
You will receive upon my part after some weeks a complete copy of
all the proceedings of the European committee on Anat. Nomenclature.

With kind regards,
W. KRAUSE.
P.S. Ihave reprinted your Preliminary Report in the Monthly
International Journal of Anat. 1891, Vol. VII, No. 5 a. 6, p. 239.

§140. My answer was as follows:

Ithaca, N. Y., Apr., 30, 1891.
Prof. W. Krause, Dear Sir:
; In response to yours of April r5th, I take pleasure in send-
ing by bookpost copies of the sheet named, and also copies of printed
lists, and of figures prepared for my students exemplifying the use of
the names. We have commonly employed the English paronyms of
the Latin words, but the latter are given in the ‘‘ Macroscopic Vocab-
ulary” [’90, 2]. You do not speak of having seen my articles in the
“‘ Reference Handbook.” Perhaps the work has not been introduced
abroad: since, however, they present my last views as to the principles
of Nomenclature, and also apply those principles to the brain, I desire
that your committee should consult them. In a separate roll will go by
bookpost a copy in sheets to be kept while of service to the committee.
Permit me to ask attention especially to the paragraphs on pp. 522
[$45] and 532 [$82.] Very cordially yours,
B. G. WILDER.

P.S. The photographs are of a column inthe same volume,
VIII, of the Handbook, in W. Browning’s article on the vessels of the
brain. He accepts and applies the principles of mononymy and
paronymy.

Wiper, Neural Terms. 259

§141. Later, March 27, 1892, I wrote:

‘¢TIn my letter of April 30, 1891, I announced that I should mail
you a copy of the sheets of the article ‘‘ Anatomical Terminology ”’
from the eighth volume of the Reference Handbook of the Medical
Sciences, published in 1889. I do not find record of its reception. If
it was lost in the mail! I will try to lend you another. Iam still of the
opinion that the article contains the essence of what has been and is to
be done, and that its perusal will not only facilitate the labors of your
committee but enable present workers in the matter to avoid neglect
and injustice toward their predecessors from Chaussier down.”

§142. To my earlier inquiry (March 20, 1892), as to
whether ,jthe Handbook article had reached him, Dr. Krause
replied under date of April 12: ‘‘The [second ?] copy of your
mentioned article has been set in circulation among the mem-
bers of the committee.”

$143. The foregoing was my last communication from
the secretary. ;A feature of the article of Prof. His (’95; see
Part VI) led me to ask Dr. Krause (Dec., 1,\ 1895) whether
the article had ever been transmitted to the former. To this
query, which was repeated July 10, 1896, no reply has been
meecived. See, however, the letterof Prof. His, Aug) 27, 1896;
Part, VI, .

§144. On the fourth of April, 1892, Dr. Krause had
sent me a list of the then members of the committee (eighteen
in number), and suggested that copies of my papers be sent to
them direct. So far as practicable that has been done ever
since.

$145. The kind offer made in Dr. Krause’s letter of
April 15, 1891, was duly fulfilled. From time to time there
reached me copies of most of the several ‘‘Abstimmungs” and
‘‘Schlussredactions”, the last arriving early in 1894. They
comprise nine hundred and forty-two large pages, and constitute
a monument to the learning and industry of the secretary of the
committee. Although not published in the ordinary sense,
the large number of the committee, their wide European distri-
bution, and the commentaries of Prof. His (’95), lead me to

1 Apparently this copy was lost in transmission ; a second was obtained
from a member of an American Committee and mailed with the above letter.

260 JOURNAL OF CoMPARATIVE NEUROLOGY.

regard occasional reference to their contents as no breach of
confidence.

$146. Besides the reprint in the ‘‘ Monatschrift” as an-
nounced in his letter of April 15, 1891, Dr. Krause reproduced
the ‘‘Preliminary Report” of the committee of the Associa-
tion of American Anatomists (1889, $81) upon p. 104 of the
‘‘Osteologie, Abstimmung I,”’ and upon p. 105 the Table of
arterial names from my paper, ’85,g. Upon p. 103 are com-
ments, translated as follows:

“In America also has been formed a committee upon Anatomical
Nomenclature. ‘Their proceedings have so far led to the herewith
published preliminary recommendations. At the beginning of Osteolo-
gy the proposal to apply thoracic instead of dorsal to a region of the
vertebral column would be taken into consideration. Wilder further
proposes to choose if possible [wo méglich] mononyms instead of poly-
onyms, i. e., to say, A. praecerebellaris instead of A. cerebelli superior.
[This last sentence is most important]. In Wood’s Reference Hand-
book of the Medical Sciences (VIII, p. 523) are discussed the advan-
tages of mononyms (single word terms) over polyonyms. That such
proposals cannot be practicable is evident from a glance at the ap-
pended list of arteries, or by recalling the binominal system of designa-
tion introduced by Linnaeus, which only made possible the develop-
ment of descriptive Natural Science.”

$147. Notwithstanding the fact that the implied accusa-
tion as to my accepting no terms consisting of more than one
word is refuted by the dionym quoted, A. (Arteria) praccerebel-
larts, this self-raised specter of an exclusive dogma of monony-
my so haunted the German committee that when their final Re-
port was adopted, April 19, 1895, the Record of the Proceed-
ings of the Anatomische Gesellschaft (Azatomischer Anzeizer,
‘‘Erganzungsheft,”’ 1895, p. 162) contains the following extra-
ordinary manifesto (here translated) :

““On motion of the Nomenclature committee (signed by the
members present at Basel, Herren von KGlliker, W. His, Leboucq,
Toldt, Fr. Merkel, Schwalbe, Waldeyer, Romiti, von Bardeleben) the
anatomical society makes the following declaration: The Anatomische
Gesellschaft believes it should take a stand with regard to the endeav-
ors of the American Nomenclature Committee. It acknowledges the
usefulness of as short names as possible, and the suitableness of some
propositions that have some from America. But it protests against the
reckless |riicksichtlose] introduction of mononyms, and against the
consequent radical remodelling of anatomical language as it has hither-

WILpDER, Weural Terms. 261

to existed. Consideration for the already established laws of common
language formation, as also regard for the historic development of our
own science, forbid the Anatomische Gesellschaft to follow the Ameri-
can committee in this way. Should the formation of a peculiar ana-
tomic vocabulary in America advance in the direction indicated, there
would then be opened an impassable gulf between the representatives
of anatomic and medical science, and consequently the codperation in
scientific work hitherto existing would be deeply disturbed.”

§148. In order to appreciate the full significance of the
foregoing, there must be borne in mind certain facts: (qa) It is
directed by the Anatomische Gesellschaft against the endeavors
[Bestrebungen] of tie American Nomenclature Committee.
(0) At that time (spring of 1895) there were four American
committees ($$80-84) representing three distinct associations.
(c) The committee of the Neurological Association had not
then reported. (d) The reports of the other three committees
were substantially embodied in that of the most comprehensive
committee of the most comprehensive association, viz., the A.
A. A. 5S., (§84), of which I was nota member. (¢) What had
been done by any American committee up to the spring of
1895, therefore, is represented by sections 1-5 of the Neuro-
logical report (S80). (/) The recommendations therein con-
tained had been adopted unanimously by the three committees
and by the three associations, hence the reference of the Ana-
tomische Gesellschaft to the American Committee, while strict-
ly inaccurate, really did no injustice.

$149. Having disposed of these historic details let us
now see whether the real divergence between the American and
German conclusions at that time was such as to warrant warn-
ings and injunctions so solemn and sweeping as are contained
in the declaration above quoted, (§147.)

$150. The American recommendations may be grouped
as (a) specific and (6):general. The specific refer to the follow-
ing terms: (1) vertebrae thoracales ; (2) hippocampus ; (3) pons ;
(4) zzsula; (5) calcar; (6) pra; (7) dura. Of these seven,
four, a majority, coincide absolutely with the German adop-
tions.

$151. The other three are discussed in Part III, §§105,

’

262 JOURNAL OF COMPARATIVE NEUROLOGY.

116, 117). As there remarked, the German adoption of fis-
sura calcarina ($108) and cavum subdurale (§118) practically
concedes the adequacy of calcar, dura and pia.

§152. The special application of dorsal and ventral to the
spinal cornua and nerve roots is involved in the general recom-
mendation of the American committees to employ those ex-
plicit adjectives in place of the ambiguous toponyms of anthro-
potomy, ($132). As already stated (133) the maintenance of
the latter by the Anatomische Gesellschaft contravened the
opinion of the oldest German anatomist, who was also chair-
man of the ‘‘ Nomenclatur Commission.’’ Americans are not
likely to repent of a step that has been sanctioned by such
authority.

$153. There remains the general recommendation includ-
ed in section 4, viz., ‘‘That, other things being equal, mono-

’

nyms be preferred to polyonyms.’’ So far as may be inferred
from the official declarations of the Gesellschaft, and from the
papers of its secretary and of Professor His, this constitutes the
most substantial element of the terminologic phantasm. which
the Germans have erected between themselves and the Ameri-
can committees.

$154. How unsubstantial even this really is may be seen
from the following facts: (a) Of the eleven specific terms
adopted by three American committees up to the spring of |
1895, five, nearly one half, were polyonyms, viz., vertebra thor-
acals, radix dorsalis, radix ventralis, cornu dorsale, and cornu
ventrale. (b) Even among the forty specific terms adopted by
the Neurological Association in 1896 (S80) nine are polyonyms,
nearly one-fourth of the whole. (c) Among the (about) five
hundred and forty neural terms adopted by the Gesellschaft, at
least forty, about one-fourteenth, are mononyms, and there are
others among the names of the other parts of the body.

$155. Inshort, before condemning the American com-
mittees for prefering CALCAR to calcar avis, and PIA and DURA
to pia mater and dura mater, the Germans must justify their
recommendation of the following mononymic substantives in
place of polyonyms all of which,are perfectly legitimate, and

Wiper, Weural Terms. 263

some of which have been hithero more commonly employed:
ATLAS (vertebra cervicalis prima); EPISTROPHEUS (Uv. ¢. secundas);
MANDIBULA (0s maxillare inferius); THALAMUS (thalamus opticus);
cuNEUS (lobulus cuneatus); PRAECUNEUS (lobulus quadrilaterus);
UNCUS (gyrus uncinatus); HIPPOCAMPUS (ippocampus mazor);
PONS (fous Varolit); INSULA (ensula Rel).

§156. Likewise, even had any one of the committees
sanctioned certain mononymic adjectives that have hitherto
been employed only by individuals, before entering upon an
Index expurgatorius such ‘‘harmless vocables”’ as ARTERIA
POSTCEREBRALIS (for A. cerebralis posterior ), GYRUS SUBFRONT-
ALIS (for G. frontalis inferior), and FisSURA PRAESYLVIANA (for
Ramus anterior ascendens fissurae cerebri laterals | Sylviz }), they
must account for the following instances upon their own list of
the replacement of qualifying phrases in perfectly good and reg-
ular standing by adjectives consisting of a single word each:
MUSCULUS EPICRANIUS (occipito-frontalis); MuscULUS PLATYSMA
(M. platysma myoides); SULCUS PRAECENTRALIS (S. centrals an-
terior); and FIssURA CALCARINA (F, occipitalis horizontalts).

§157. Notwithstanding, however, the above enumerated
German examples of mononymy, it must be admitted that there
still exist somewhat radical distinctions in principle between the
committees of the two nations. Good words may be predicated

)

of both; but so may ‘‘ good works” be done sometimes by

the ‘‘unjust”’ as well as by the ‘‘just.”” The real distinction
lies not so much in specific deeds as in general preference.

$158. Asearly as 1891, the principles upon which the
German committee proposed to base their revision of Anatomic
Nomenclature were formulated and announced as_ follows
(Krause, “ol, 2):

‘Die erwaihnten Grundsiatze sind nicht so zu verstehen, als ob
sie etwa ausnahmefreien Naturgesetzen entsprechen sollten. Ihre For-
mulirung ist um so mehr als eine provisorische zu betrachten, als es
sich hier nur um die Myologie handelt.

1. Jeder Kérpertheil darf nur einen einzigen lateinischen Namen
haben. Es geht nicht an, wie es manche Handbiicher thun, sich mit
einem sive zu helfen und die beiden Ausdriicke dann abwechselnd zu
gebrauchen. Deutsche Benennungen, insofern sie nicht ohnehin

264 JOURNAL OF COMPARATIVE NEUROLOGY.

feststehen oder soweit sie iiberhaupt néthig, bleiben der freien Aus-

wahl eines Jeden iiberlassen.
2. Der Name soll ein kurzes sicheres Merkzeichen sein und

weder eine Beschreibung noch eine speculative Betrachtung in sich
einschliessen.
3. Kein KOrpertheil soll einen unnéthig langen Namen fiihren.
4. Kein K6rpertheil soll denselben Namen haben, den schon
ein anderer fiihrt, mit Ausnahme etwa des Falles, wenn es sich um

Homologien handelt.

5. Die Namen sollen sprachlich und orthographisch richtig sein.

6. Die Benennungen nach Personen werden so viel als thunlich
vermieden, namentlich wenn sie betrachtliche ‘ historische Unrichtig-
keiten enthalten.

7. Im Ganzen will die Commission conservativ im weitesten
Sinne verfahren.”’

§158. In the following translation the bracketed interpo-
lations refer to definitions or commentaries in the present
article.

‘¢ The principles here stated are not to be understood as if meant
for laws of nature free from exception. Their formulation is all the
more to be regarded as provisional, since muscles alone are here in
question :

1. Each part of the body should have a single Latin name. One
should not, asin many manuals, employ a sive, and then use both
expressions alternately [pecilonymy, §34]. German designations
[heteronyms, $43], in so far as they are not already established, or so
far as they are really necessary, are left to the free choice of the
individual.

2. The name should be a short definite expression (sicheres
Merkzeichen) and indicate neither description nor speculative obser-
vation, [$51, from Owen].

3. No part shall have an unnecessarily long name [magniloquy,

40]. :
: iS No part shall have the same name that already belongs to an-
other, except in the case of homologues, [homonyms, §§23, 67].
5- The name shall be grammatically and orthographically correct.

6. Personal designations are to be avoided as much as possible,
especially when they contain considerable historic errors; [eponyms,

§33]-

7. In general the commission intends to act conservatively in
the widest sense of the word.”

$159. In August of the same year Dr. Krause presented
to the British Association for the Advancement of Science a
brief statement of principles (Krause, 0) and commentary there
on. The essential parts are here reproduced.

Wiper, Neural Terms. 265

‘‘ The state of things has every year become worse and worse ;
in Germany especially it has become almost insupportable [$$58-60]
* * %* In the same university sometimes different anatomical no-
menclatures exist. * * * In two orthiee years we shall have
finished and then we shall ask the anatomists of other countries to give
their candid opinion on the whole. '

1. The name should be as short as possible.

2. Personal nomenclature should not if possible be used.

3. No part should have more than one name.

4. This name shall always be a Latin one; every nation can af-
terward easily translate it [$42] after its own fashion. Latin is the
only real international language [$46], and by adopting it we hope to
have a sound foundation.”

§160. For the most part these principles are to be com-
mended. Before suggesting qualifications of the fourth items
I cannot refrain from calling attention to the absolute lack of
intimation either that any of these principles had ever been
enunciated before, or that any individual or committee had ever
undertaken to effect an improvement in anatomic language.
Granting the inutility of American precepts and examples that
a German should present to an English scientific body proposi-
tions as to terminologic reformation as if they were wholly
original and without (so far as recorded) naming those apostles,
Barclay, Whewell, Owen, and Pye-Smith (the last still living),
was surely most incongruous.

§161. It will be seen from the various passages above
quoted that the Germans are at last ' in accord with the Amer-
icans in recognizing the value of brevity as a feature of ana-
tomic terms. But I have as yet failed to find in their publica-
tions or private letters even the faintest glimmer of comprehen-

1 T say at Jast, in view of the enormous number of lengthy terms, both Latin
and vernacular, for whose continuance and even origia German anatomists are
responsible ; 260. Some of the heteronyms are indeed ‘‘ fearfully and wonder-
fully made,” and can be most fitly characterized as verbal ‘‘ tandems,”’ unman-
ageable by persons not specially trained. As remarked by Owen, ‘‘ The happy
facility for combination which the German language enjoys has long enabled
the very eminent anatomists of that intellectual part of Europe to condense the
definitions of anthropotomy into single words; but these combinations cannot
become cosmopolitan; such terms as ‘Zwischenkiemendeckelstiick,’ are likely to
be restricted to the anatomists of the country where the vocal powers are trained
from infancy to their utterance.”

266 JOURNAL OF CoMPARATIVE NEUROLOGY.

sion of the more fundamental grounds upon which the Ameri-
can committees prefer not merely that terms should be reason-
ably short, but also, when practicable, consist of single words
each, i. e., mononyms, or, at most, of two words each, a noun
and a mononymic adjective.

$162. In addition to the incidental previous re ferences to
the subject in the present paper (§$25, 47, 50) the differences
between the more and the less essential advantages of mono-
nyms over polyonyms may be fairly indicated by extracts from
two earlier articles. The first (’84, e) was presented to the
American Association for the Advancement of Science in con-
nection with my suggestion that a committee on Anatomic No-
menclature be appointed by that body. Since it contains no
reference to prior terminologists, it may be proper to add that,
as published, it was a mere abstract, and that in both earlier
and later papers of greater’ length (31, 0, c; W21GeNGpees
’89), an effort was made to give due credit to those who had
either indicated or smoothed the way.

$163. ‘*7. Should not organonymic terms (terms of designation)
be, as far as practicable, brief; capable of inflection; classic in deriva-
tion and form; already used in a kindred sense? !

8. Since the length of aterm may depend upon not only the
number of syllables and letters, but also upon the number of separate
words, and since, properly, only single words are capable of inflection,
is there not a twofold reason why the names of parts, weth certain self-
evident exceptions, (nerves, etc.2) should be mononymic ?

g. Is there much real analogy between the nomenclature of
anatomy and that of zoology and botany ? [cf. $146, last line.]

10. How far should priority be regarded in the selection of ex-
isting names ? ;

11. Can priority be claimed for terms which are vernacular or
descriptive ?

12. In considering all questions of terminologic reform, should
we not regard less our present and personal convenience, than the in-
terests of the vastly more numerous anatomical workers of the future?”

\ [This note was a part of the paper.] ‘In later papers ('85, 4 and ¢) I have
suggested that, in English works, so far as possible, the names be given an Eng-
lish aspect by paronymization. For example, commissura becomes commissure ;
pedunculus, peduncle, With many names no change is needed, as with Zorta,
aulix, fornix, callosum, etc. Heteronyms or vernacular translations are regarded
as objectionable. The same principle is applicable to other languages,”

2. This phrase is italicized for a reason that will appear later, 2172.

Wiper, Weural Terms. 267

§164. The distinctions were more fully set forth seven
years ago in the later article (W. & G., ’89, 523) from which
is taken the following summary.

A. From mononyms adjectives may be regularly derived.

B. Mononyms are more readily compounded.

C. Mononyms are constant in form, excepting for the regular
derivatives, numbers, cases, adjectives, and paronyms.

D. Polyonyms, on the contrary, are subject to variations of sev-
eral kinds: (a) By omission of words. (4) By the conversion of gen-
itives into adjectives. (c) By the substitution of totally different words.
(2) By permutation ($37).

E. Mononyms may be more uniformly abbreviated ($38).

F. Mononyms are commonly shorter than the corresponding
polyonyms. The exceptions are due to the fact that the absolute
length of a term depends upon three factors, viz , (a) the number of
words ; (6) the number of syllables in the words; (¢) the number of
letters in the syllables. The written length of a term is affected by
all three of the above named conditions ; but its spoken length is in-
dependent of the number of letters.

$165. But the essential characteristic and principal advantage of
the Latin mononym is (G) that 772s capable of adoption into any other
language, either unchanged, or with so slight amodtfication as not to hinder
tts ready recognition by the anatomist of any nationality.

$166. Between longer and shorter words is merely a difference
in degree, e. g., crus and pedunculus; between a Latin word and its
vernacular equivalent or heteronym (e. g., pedunculus and footlet) and
its paronym (peduncle) the choice might depend upon individual pref-
erence; but mononyms and polyonyms, terms of one word each and
terms of two or more (e. g., pedunculus and pedunculus cerebelli) differ
in kind; it is not a question of size or euphony, but of essential en-
dowment and capacity. The mononym is to the polyonym as is the
water to the earth or as is the bird to the tortoise.

$167. The desirability of replacing polyonyms by mononynms is
in direct ratio with the frequency with which the part is mentioned,
and with the need of employing corresponding adjectives. Mypophy-
sis (formerly pituitary body) and conarium (formerly pineal gland) are
much more frequently named since the discovery that the former has
peculiar developmental relations with the pharynx, and the latter even
more remarkable connection with a vestigial organ of sight. So long
as the thin sheet of nervous tissue just dorsad of the chiasma was re-
garded as insignificant, and even as occasionally absent, either damina
cinerea or lamina terminals might not be so objectionable ; but its now-
admitted morphologic importance as the cephalic boundary of the en-
cephalic cavities justifies the use of the mononym, éerma. The ort
fice left by the removal of the hypophysis and infundibulum had ap-
parently received no name up to 1880; foramen infundibult was a suf-
ficiently appropriate descriptive term ; but the frequency of its men-
tlon in notes respecting the preservation of the brain led me to discard

268 JOURNAL OF COMPARATIVE NEUROLOGY.

it in favor of Jura. The first two cervical vertebrae alone have mon-
onymic titles ; but were there similar anatomical, physiological, or
surgical occasions for specifying any other member of the vertebral
series, a mononym would probably soon be proposed and generally
accepted.

§168. The German criticisms of the American methods
and results quoted above (§$147-153) are comparatively brief
and general. A more extended and particular arraignment is
contained in the article of Prof. Wilhelm His (95, 6-7). Al-
though published under his name, yet its association with the
official list of Momzna anatomica' as adopted by the Gesellschaft,
the prominent part taken by him in the formation and work of
the committee,and his high reputation based upon splendid con-
tributions to science extending through many years, all endow
his utterances upon the subject with not merely personal but
semi-official significance. Indeed, in the absence (so far as I
know) of any dissent therefrom, those utterances must be re-
garded as representing the views of the older German anatom-
ists?» On this account it is more to be regretted that some of
his criticisms should exhibit in a marked degree the lack of in-
formation and of comprehension mentioned in the introduction
to the present article (§§3-4).

$169. Criticism by Prof. Wilhelm His (’95, 6-7).°

‘‘Die anatomische Gesellschaft Grossbritanniens hat 1893 eine
eigene Commission zur Anpassung unserer Vorschlage an die englisch-
en Bediirfnisse niedergesezt,4 und etwas friiher noch (1890) hat eine
Gesellschaft amerikanischer Anatomen die Nomenclaturfrage in die
Hand zu nehmen versucht. Die Aeusserungen der englischen Com-
mission liegen noch nicht vor, dagegen haben die amerikanische
Commission und deren sehr eifriges Mitglied, Hr. Wilder, bereits

1It would be desirable to know whether the list may be obtained otherwise
than as part of the article, as will be the case with Part VII of the present
paper.

2By some of the younger neurologists the American ideas have been more
hospitably entertained and certain newer terms actually adopted.

3The original is here reproduced verbatim et literatim et punctuatim, In the
translation (7170) I have ventured to modify certain subordinate features that
may have been due to haste upon the part of the author or proof-reader.

4 Journal of Anatomy and Physiology, 1894. Vol. XXVII [XXVIII].

WiLvER, WVeural Terms. 269

eine Reihe von kleineren Aufsitzen und Broschiiren ver6ffentlicht!

‘‘Die Ziele, welche die amerikanische Commission verfolgt,
sind dieselben wie die unsrigen, ihre Wege zum Ziel sind aber
wesentlich andere, als die von uns gewahlten. Gemeinsam ist uns
der Grundsatz, dass jeder Theil nur einen einzigen Namen haben
soll, und dass dieser Name méglichst einfach und bezeichnend zu
wahlen sei. Wilder und seine Collegen gehen aber weiter und verlang-
en lauter ‘‘ Mononyme,” d. h. Substantive ohne ferneren Zusatz.
Sie sagen z. B.: praecornu und postcornu satt cornu anterius und
cornu posterius, postcava statt vena cava posterior u. a.m. _ Bis jetzt
liegt von Wilder die Bearbeitung der Gehirnnomenclatur nach den vor-
geschlagenen Grundsiatzen vor, und dieser erste Versuch erlaubt uns
ein Urtheil iiber die Consequenzen, zu welchen das vorwiegende Bes-
treben nach Mononymen hinfiihrt. Wir stimmen unsererseits vollig
bei, wenn das wort Thalamus kurzweg an die Stelle von Thalamus op-
ticus gesetzt wird, wir haben selbst nichts dagegen, wenn im taglichen
Verkehr das Wort Dura fiir dura Mater encephali in allen den Fallen
gebraucht wird, wo eine Verwechselung ausgeschlossen bleibt. Da-
gegen kénnen wir nicht anerkennen, dass Worte wie ‘‘ Medipeduncu-
lus” fiir Pedunculus cerebelli ad pontem einen sprachlichen oder
praktischen Fortschritt bedeuten. Die Zusammenziehung verschied-
ener Worte in ein einziges kann ja unter Umstanden eine Vereinfach-
ung sein, Aehnlich dem allzu gedrungenen Telegraphenstil kann sie
indessen auch zur Unklarheit fiihren, und dann ist ihr Nutzen ein neg-
ativer, denn also gebildete Worte verlangen zu ihrem Verstandniss
besondere Erlauterungen. Medipedunculus ohne Zusatz ist unver-
standlich, es miisste schon Medipedunculus cerebelli heissen, und dem
ware wiederum Pedunculus medius cerebelli vorzuziehen, weil das
barbarisch gebildete Wort Medipedunculus ebensowohl fiir Pedunculus
medius, als fiir Pedunculus medialis oder fiir Pars media oder medi-
alis pedunculi gebraucht werden kénnte. Sprachwidrige Wortzusam-
mensetzung enthalt aber Wilder’s Liste sehr viele, und man hat nicht
néthig, ein philologischer Pedant zu sein, um in Worten wie Terma
(anstatt Lamina terminalis), Postramus (fiir Ramus posterior arboris
cerebelli) u. a.m. Aergerniss zu nehmen. Viele Worte, wie Cimbia
(Tractus peduncularis transversus), coelia (fiir Cavitas encephali),
Aulix (fiir Sulcus Monroi) u. a. m. sind iibrigens neu oder wie Isth-
mus (fiir Gyrus annectens) in einem anderen, als dem bisherigen Sinn
benutzt. Ich weiss nicht, wie weit der Kreis amerikanischer Fachge-
nossen reicht, welchen Wilder hinter sich hat. Jedenfalls fiihrt das

1Von den durch Wilder versandten Schriften citire ich als die hauptsachlich-
sten. The fundamental principles of anatomical Nomenclature, by Burt C.
Wilder MD. from the Medical News. 19. December 1891.

Ferner: Fissural diagrams of the human brain. Macroscopical Vocabu-
lary of the brain presented to the Assoc. of American anatomésts at Boston, Mass.
29. Dec. 1890. American Reports upon Anatomical Nomenclature. 1889-
1890, with Notes by Wilder, Cornell University, 5. February 1892.

270 JouRNAL OF CoMPARATIVE NEUROLOGY.

Vorgehen des letzteren zur Schaffung einer véllig neuen, grossentheils
recht fremdartig klingendeti Sprache, und auf diesen Boden kann
ihm unsere Commission, ohne Verleugnung ihrer historischen Grund-
satze, nicht folgen.”

§170. In the following translation of the foregoing extract
from the article of Prof. His (’95, 6, 7), besides corrections of
supposed typographic errors, and changes in the order of words
in accordance with more usual English custom, there are intro-
duced in brackets (2) words from the original that might have
more than one meaning ; (2) references to sections of the pres-
ent article; (c) letters to facilitate the assignment of subsequent
commentaries to the special points involved.

‘« The anatomical society of Great Britain appointed in 1893 its
own commission to adapt our propositions to English needs,! and
somewhat earlier still (1890), [a] a society of American anatomists
[4] tried to take up the nomenclature question. The statement of the
English committee is not at hand, but the American committee [c]
and its very ardent member, Mr. Wilder [d ], have already published
a series of small papers and dbrochures.2 The aims of the American
committee are the same as our own, but their methods are essentially
[7] different from those chosen by us. The fundamental idea is the
same, that each part should have only a single [Latin] name (§46),
and this the most simple possible [g]._ But Wilder and his colleagues
[Z] go farther and desire [z] absoiute [verdangen wists mononyms, 2. é.,
substantives without further additions. They say [7], for example,
praccornu and postcornu instead of cornu anterius and cornu posterius ;
postcava [| instead of vena cava posterior, with many similar terms.
We have already the treatment of encephalic nomenclature by Wilder
in accordance with the proposed method, and this first attempt allows
us [/] to form an opinion as to the results [7] to which the preponder-
ating |vorwzegende| effort toward mononymy leads. On our part we
assent fully when the word ¢halamus alone [7] takes the place of thal
amus opticus ; we even do not object if, in ordinary communications,

1 Journal of Anatomy and Physiology, XXVIII [not XXVII, as in original],
pp. VII-IX, 1894. »

2T cite here the chief [Aauptsdchlichsten] of Wilder’s [e] transmitted [ver-
sandten| publications: ‘‘The fundamental principles of Anatomical Nomencla-
ture,’”? The Medical News, Dec. 19, 1891, 708-710. ‘‘ Fissural Diagrams,” accom-
panying ‘‘ Remarks on the Brain of Chauncey Wright, with Commentaries upon
Fissural Diagrams,’’ Jour. of Nervous and Mental Disease, XVII, 1890, 753-754;
Amer. Neurolog. Assoc. Transactions, 1890. ‘‘ Macroscopic Vocabulary of the
Brain, with Synonyms and References ;”’ presented to the Association of Amer-
ican Anatomists, Dec. 29, 1890; O., pp. 13. ‘‘ American Reports upon Ana-
tomical Nomenclature, 1889-1890, with Notes.” O., pp. 3, Feb. 5, 1892.

Wiper, Neural Terms. 27%

[0] the word dura for dura mater encephalt is used when misapprehen-
sion is impossible. But we cannot acknowledge that words like med¢-
pedunculus |p| for pedunculus cerebelli ad pontem constitute a linguistic
or practical improvement. The contraction of several words into a
single one may be under certain circumstances [g] a simplification ;
but, as with the too concise telegraph style [7], it may, on the other
hand, involve lack of clearness, and then its advantage 1s negatived ;
for words formed in this manner demand a special explanation for their
comprehension. Medipedunculus alone is unintelligible [s]. It must
surely be called medipedunculus cerebelli, and over this again should
preference be given to pedunculus medius cerebellit, because the barbar-
ously formed [/] word medtpedunculus could be used indifferently for
pedunculus medtwus, for pedunculus medialis, or for pars media or medtalis
peduncult [uw]. But Wilder’s list contains very many [v] ungrammatic
verbal combinations, and one need not be a philologic pedant [zw] to
take offense at words like ¢erma (instead of lamina terminalis) [x], post-
ramus (for ramus postertor arboris cerebellt) |y| and others. Man
words like cimbia (for tractus peduncularis transversus) [2], coelta (for
cavitas encephalt) |a|, aulix (for sulcus Monrot ) ||, and others, are
moreover new [7], or, like ¢sthmus (for gyrus annectens), used in another
than the accepted sense. I know not how far may extend the circle
of American collaborators supporting Wilder [0]. At all events, his
proposals tend to create a language entirely new [<] and for the most
part quite strange, and on this ground our commission cannot follow
him, without renouncing its historic principles [y].”

§171. Certain points in the foregoing extract have already
become the subjects of the correspondence between Prof. His
and myself referred to in the Introduction ($4) and constituting
Part VI. Their inclusion in that later division of the present
article is the more desirable in view of the hope based upon
my last letter from Prof. His that, before that part is put in
type, he may have discussed those points publicly.

$172. It will be seen that, like the German committee
and the entire Gesellschaft, Prof. His is disturbed by the Amer-
ican preference for mononyms.. In one passage he character-
izes it as the ‘‘vorwiegende Bestreben” [m]; in another [i]
by ‘‘verlangen lauter.”” Now verlangen has two distinct mean-
ings, viz., deserve or prefer, and demand or insist upon. As will
appear in Part VI, it is now (Nov. 10, 1896) nearly a year since
Prof. His had an opportunity to state in which of these senses
the word is to be understood, and more than two months have
elapsed since the ambiguity was brought expressly to his notice.
The sweeping charge (§147) framed by the Gesellschaft in his

272 JOURNAL OF COMPARATIVE NEUROLOGY.

presence and apparently under his direction would justify the
interpretation of verlangen as demand. But until assured to that
effect by Prof. His himself, I hesitate to entertain so monstrous
a perversion of the facts upon the following grounds: (a) In all
the reports of the American committees the expression of pref-
erence for mononyms is accompanied by the proviso ‘‘ other
things being equal.’”’ (0) I have repeatedly conceded the im-
possibility of the application of the principle to groups of parts,
fissures, gyres, vertebrae, bloodvessels, muscles and nerves.
The remark that there are ‘‘certain self-evident exceptions
(nerves, etc.),” occurs in a paper ('84,¢; $163, 8) presented
by me twelve years ago to the American Association for the
Advancement of Science and printed in the Proceedings of that
body (pp. 528-529). If Prof. His ever consults any American
scientific publication it would seem not unnatural that the title of
that paper, ‘‘Onsome Questions in Anatomical Nomenclature,”
should have attracted the notice of one who, three years later,
himself urged (’95, 1) upon the German anatomical society the
need of action upon the subject, and who was occupied. there-
with more or less for eight years afterward.

$173. In order to eliminate so far as possible the personal
element from the consideration of the special criticisms of Prof.
His, I select as the first subject of rejoinder a term, Postcava,
in which my interest is only indirect, as of one toward a child
by adoption rather than by paternity. Omitting intervening
phrases not affecting the interpretation, the complaint of Prof.
His reads (translated) as follows :—‘‘ Wilder and his colleagues
[4] * * * say [7] praccornu and postcornu for cornu anter tus
and cornu posterius, postcava [k| for vena cava posterior, with
many similar terms.’’ The implied disclaimer as to ‘‘ philologic
pedantry ” [zw] can hardly embrace a toleration of misstatement ;
hence, before discussing the intrinsic merits of the word se-
lected, it may be well to dispose of minor points that might
complicate the main issue.

$174. In the text Prof. His refers only to ‘‘ Wilder,” and
in note 2 (see the original, $169) an initial is wrong. Hence it
is only just to state that my terminologic transgressions must

Witper, Neural Terms. 273

not be imputed to Harris H. Wilder, professor in Smith Col-
lege, Northampton, Mass., whose researches, especially upon
lungless salamanders,’ make me proud to claim him as a distant
relative.

$175. The objectionable words are attributed to ‘‘ Wilder
and his colleagues.”” Not one of the three specified words, or
of the ‘‘many similar terms,” has been sanctioned by either
of the four committees, and few of the members thereof have
adopted them. For the confusion and possible injustice here
occasioned no adequate explanation can be offered.

§176. The phrase ‘‘postcava statt vena cava posterior”
would naturally imply that the latter is the name preferred by
the German committee. Yet the official list contains (p. 77)
only vena cava inferior.”

$177. So far as appears in the article of Prof. His, fost-
cava was coined by me. On the contrary, so far as I am aware,
it (in the derivative, postcava/) was first introduced by Richar d
Owen about the middle of the century, and employed by him
consistently thereafter.

§178. Whether or not the two historic facts just men-
tioned® were known to Prof. His he alone can tell, and the fate
of other queries does not encourage an effort to ascertain.
Hence I am compelled to offer propositions which each reader
must accept, or reject, or explain in accordance with his own

”

information and judgment.

(1). Postcava, inthe form fostcaval (§177), occurs fre-
quently in the writings of a leading English anatomist.

(2). Those writings must be known and accessible to Prof.
His. Hence there is no excuse for the erroneous intimation in
the article.

1 Anatomischer Anzeiger, 1X, Jan. 20, 1894, and XII, 182-192, 1896.

+ In passing it may be remarked that the retention of superzor and inferior
as the essential elements of the designations of these great vessels constitutes
one of the many evidences of the non-emancipation of the German committee
from anthropotomic enslavement; see 2133.

3 My non-responsibility is certain; the responsibility of Owen is assumed
in the absence of evidence to the contrary.

274 JOURNAL OF CoMPARATIVE NEUROLOGY.

(3). Whatever its source, postcava differs from the more
usual terms in its comparative brevity, while at the same time
not open to the charge of ambiguity. Why then was it not in-
. Cluded in the column of synonyms from ‘‘ sonstigen Autoren”
in the protocols of the German committee, as was a less com-
mon and acceptable synonym, viz., ‘‘ vena cava _ inferior
thoracica ?”’

(4). If the entire committee supposed me to be the au-
thor of postcava, their action was consistent, since no term is
credited to me in the column indicated.

(5). But if any members of the committee knew that
posicava originated with Richard Owen, their objections to the
word might well have been waived out of respect for him.

§178. The actual form employed by Owen is specified
above, not merely for the sake of accuracy, but also in order to
forestall criticism upon a point where disagreement is possible.
It is, I think, a sound proposition that the zntroduction of any
derivative, oblique case, or national paronym, practically renders
the introducer responsible for the actual or potential Latin antece-
dent of such words, in accordance with the usual rules of derivation
and paronyny. 1 donot remember seeing the foregoing propo-
sition distinctly formulated,’ but reflection will show its sound-
ness. One of the wisest recommendations of the A. A. A. S.
Committee on Biological Nomenclature ($85) was that the Latin
(international ) form of a term should always be given, whether
or not the national paronyms. Now cava is the feminine form
of cavus, and vena cava was used (perhaps not in the specific
modern sense ) by Cicero, ‘‘De Natura Deorum,” 2, 55, 38.”
There seems to have been no classic adjective, although cavatus,
the participle of cavo, was available as such. Analogy fully
warrants (S116, et seq.) the acceptance of cava as a subsian-
tive, and the derivation therefrom of a secondary adjective in the
form of either cavatus or cavalis. The latter evidently was

1It probabiy has been in purely linguistic connections.

* For some discussion of cava see Hyrtl, ’80, 98, 99.

Wiper, Neural Terms. 275

chosen (constructively) by Owen when (in 1862, ‘*Onthe Aye-
Aye,”’ Zool. Trans., V, 86, and perhaps earlier) he employed
post-caval vein and pre-caval vei. Later, the hyphen was
omitted, and in the ‘‘ Comparative Anatomy of Vertebrates ”’
occur ‘‘postcaval vein, postcaval trunk, postcaval orifice, and
postcaval,) 0503-505; 11, 203); TIT, 552 et seq. ) Bending
the discovery in Owen’s writings of some history of the stages
by which the final reduction was effected, the following series
is certainly thinkable:—(1) Vena cava posterior; (2) Posterior
vena cava; (3) Posterior caval vein; (4) Post. caval vein; (5)
Post-caval vein ; (6) Postcaval vein ; (7) Postcaval ; (8) Postcava.
Whatever may have been the actual steps, never did Owen
reach a more final terminologic result, and no case better
exemplifies the unwisdom of the reactionary attitude of the
German committee.

$179. Since Professor His offers no specific objections to
postcava their nature can only be inferred from his general re-
marks and from his criticisms of medzpedunculus. Perhaps there-
fore the simplest and most comprehensive rejoinder is to recap-
itulate briefly the several attributes of the term, leaving each
reader to estimate their value for himself. Besides references
to this article, the initial G will indicate terms adopted by the
Anatomische Gesellschaft, or attributes commended by that
body.

(a) Brevity; §§40, 50; G., §158, 3. (6) Latin form;
§50; G., §158, 1. (¢) It isa mononym; §§15, 47. (d) It is
a locative name; §27. (¢) It is an adjectival locative; §29.
(f) It is capable of inflection, i.e., postcavalis, postcaval, post-
cavals. (g) Its various national representatives (paronyms
$$43-45) differ little or none from the international antecedent.
(2) It has in the derivative, pos/caval, high authority (Richard
Owen) and moderate antiquity (1862 or earlier). (¢) It is an
idionym ($24) and not likely to be applied to any other part in
any vertebrate. (#) It is sufficiently euphonious, and easily re-
membered. (/) Like other euphonious and easily remembered
mononyms it constitutes no bar to the progress of one who may
never have heard the more common polyonyms. Those who

276 JoURNAL OF COMPARATIVE NEUROLOGY.

are familiar with those polyonyms, whether vexa cava infertor,
vena cava ascendens, or vena cava posterior, could hardly fail to
recognize its signification. Since 1881 no other term than Jost-
cava has been used by me for the great vein in question. I
have yet to learn of a single instance of misapprehension or
other difficulty caused thereby among either general or special
students.

§180. There remains the question of the etymologic or-
thodoxy of postcava, and this involves the much more comprehen-
sive and difficult question as to the definition of etymologic
orthodoxy. Without presuming to invade the jurisdiction of
philologic experts, for the practical discussion of the case in
point, precedents need be sought in only two periods, the classic
and the recent.

$181. I freely admit that there is known to me no in-
stance in classic Latin literature of the employment of jos?,
whether alone or in composition, with the force of an adjective
and as equivalent to posterus or posterior. That this negative
evidence is hardly conclusive may be seen froma single case
among the scores that might be adduced. With the Romans
ztem was anadverb. With us it is not only an adverb, but also
a noun and a verb, and the basis of two derivatives, zdemzze and
atemiser.

§182. In recent times the precedents are partly direct and
partly indirect. Among the former are fostabdomen, postact,
postarytenoid, postfactor, postfurca, postpubis, postscapula. In all
of these post has the force of an adjective, not of a preposition.

$183. Indirect precedents are cases in which other prepo-
sitions have the force of adjectives in composition. Such are
preadaptation, precentor, preexistence, preformation, presternum ;
also subgenus, subflavor, subfactor, submaster, subtitle."

$184. Since, however, the German committee sanction
none of the anatomic terms in the foregoing lists and avoid the

1 Among analogous Greek words the following has been furnished me by
my friend, L. L. Forman, Instructor in Greek at Cornell University : npogviag,
an advance guard,

WiILpER, Neural Terms. 277

use of praesternum by retaining manubrium sternt, they would
probably decline to regard them as adequate justifications for
postcava. But can they consistently. condemn it or any sim-
ilar terms? Let us see.

§185. Prof. His, the German committee, and the Ana-
tomische Gesellschaft, after several years deliberation and appar-
ently without any disagreement, have adopted and recommended
the names metencephalon and prosencephalon for certain segments
of the brain. Now meta and pros are the English forms of the
Greek perd and zpég. These are both prepositions. Like post
and prae they are also adverbs. The terms into which they
enter have no reference to a third part ‘‘behind’”’ which or
‘before’ which the metencephal and prosencephal are situated.
The German translation of prosencephalon is Vorderhirn, and the
English, forebrain, both signifying the first or most cephalic
member of the series of coordinate encephalic segments. With
slight modifications the foregoing remarks apply equally toa
third name adopted by the German committee, dencephalon,
the preposition 6a having the force of an adjective.

§186. Iam unable to recognize any distinction, logical or
etymological, between the metencephalon and prosencephalon
which the Germans commend, and the fostcava and praccava
which Prof. His condemns. The irregular terms for which he
is in part responsible may be few; but his virtuous denunciation
of me for producing a larger number of the same sort is no
more reasonable than the demand of the woman to be punished
lightly for bringing forth an illegitimate child upon the ground
that it was ‘‘such a little one.”

§187. Strictly, however, even if the degree of oppro-
brium to be cast upon the individual concerned were to be
measured by the number of terms of a certain kind, this
would have no bearing upon the question of the acceptability
of agiven term. /Postcava and praecava are to be considered
upon their merits as brief, convenient, and absolutely unambig-
uous designations intended to replace inconvenient descriptive
phrases. In favor of vena cava superior and vena cava inferior

278 JOURNAL OF COMPARATIVE NEUROLOGY.

antiquity alone can be urged; against praecava and postcava
can be alleged only the sinfulness of comparative youth.

_ $188. Inthe foregoing discussion I have refrained from
following one line of argument that readily suggests itself and
is, indeed, almost formulated in the hypothetic series between
posterior vena cava and fostcava as stated in $178, wvzz., The
prefix post might not unnaturally be regarded as the abbrevia-
tion of posterior or postero. Were compounds of fost alone con-
cerned, this simple line of argument might perhaps be adequate;
but it will not serve for compounds of the correlative pvae, nor
for those of the Greek prepositions, éx/, yerd, ixd, etc.

§189. The straightforward way of dealing with the mat-
ter is to assume that fostand prac, in composition, may have
the force of the adjectives posterior and anterior respectively.'
‘<Tf this be treason, make the most of it.”

S190. It seems to me that the nature of the issue between
postcava and vena cava inferior (or posterior) is such as to in-
volve the acceptance or rejection of the following propositions.

A. Language was made by and for man, and not the
reverse.

B. Grammatic rules are framed from time to time in order
to maintain the uniformity that is acceptable and convenient.

C. Like the roads we traverse, such rules are but means
to ends, and have no intrinsic sanctity.

D. Like a circuitous but familiar road, a commonly ac-
cepted rule is not to be abandoned without reflection. On the
other hand, no more is it to be laboriously travelled when new
conditions render a ‘‘short cut”’ desirable.

E. Extrinsic toponyms (2. ¢., terms of location or direc-
tion that do not refer expressly to the recognized body-regions,
dorsum, venter, etc.) should conform to the more usual verte-
brate attitude rather than to the erect attitude of man; e. g.,

1 Tt is well understood in this country that the Vew York Medical Journal
and the ‘‘ Encyclopaedic Medical Dictionary ”’ stand for the highest scholarship.
Yet so long ago as 1885, when some of my simplified terms were submitted to
him, their editor, Dr. F. P. Foster replied, * I think some of the words excel-
lent, Araccommissura, for example.”’

Wiper, Neural Terms. 279

posterior and antertor, supertor and inferzor, and their deriva-
tives, compounds, and abbreviations, should have significations
zootomic rather than anthropotomic.

F. There now prevail and are likely to persist two con-
ditions not merely unknown to the Paires anatomict, but prob-
ably not imagined by them: (a) the enormous increase of ana-
tomic and physiologic knowledge; (0) its general diffusion
among the people.'' These two conditions” militate against the
rigid maintenance of grammatic rules that might prevent the
establishment of new and shorter channels, or the fabrication of
new and briefer technical terms, the ‘‘tools of thought.”’
Terms like vena cava posterior are obtrusively Latin, and hence
not acceptable to the laity; too much time and space are lost in
speaking and writing them, and time and space are daily becom-
ing more precious.

§1g1. Consciously or unconsciously, for many years Eng-
lish and American anatomists have been gradually simplifying
their terminology in substantial accordance with the foregoing
propositions. In Germany the signs of such improvements are
as yet comparatively few.

§192. Even if, however, the German committee were
reconciled to the employment of certain prepositions in compo-
sition with the force of adjectives, there would still remain’
special objection to fost as indicating toward the tail rather than
toward the back. This objection is radical, and the conflict in-
volved is irrepressible ; $$131-133.

§193. Postramus.—To this, as a mononymic substitute
for Ramus posterior arboris vitae cerebel, Prof. His offers no

1 Tn fulfilment of the declaration of the elder Agassiz, ‘‘ Science must cease
to be the property of the few; it must be woven into the common life of the
world.”

2 There is really a third condition, equally novel, but bearing less directly
upon the present question, viz., the pursuit of anatomy by women. Whatever
view may be taken of this in other respects, all decent men must rejoice that it
has hastened the elimination of the needless Momina impudica which formerly
defiled even the description of the brain. For further commentary upon this
matter see W. & G., ’82, 27.

3’ Excepting with the chairman, 2133.

280 JOURNAL OF COMPARATIVE NEUROLOGY.

specific objections (§170, v) but they may be inferred to be (a)
that it isa post compound (§§174-191); (0) that the German
list does not include any terms for the branch-like divisions of
the cerebellar ‘‘tree.’’ If these branches no longer merit spec-
ification, postramus and pracramus will vanish quietly with the
polyonyms from which they were condensed.

§194. Terma.—From the context (§170, #) it may be in-
ferred that this is objected to upon etymologic grounds. Ter
ma does not, it is true, occur in classic Latin lexicons. But
neither does chzasma which is embraced within the German list.
The latter is the ‘‘new Latin” paronym of yiacua, and ferma is
merely somewhat newer Latin for répya. Why should we use
the longer Latin terminus for terma any more than the longer
Latin decussatio for chiasma?

§195. Aulx.—This (§170, f) is the regular Latin paronym
of avija& and signifies a furrow. It was proposed by me asa
mononym for Reichert’s Szdcus Monrot, not merely as a mono-
nym but because its resemblance to az/a’ readily recalls the
fact that it connects the lateral orifice of the aula (the porta)
across the face of the thalamus with the funnel-shaped orifice of
the ‘‘aqueduct.”’ If, as apparently held by His and Minot, this
furrow should prove to be only part of the general boundary
line (Sulcus imitans ventriculorum or Sulcus interzonals) between
the dorsal and ventral zones, then it might not need specifica-
tion. But the later observations of Mrs. Gage (96, a), as stat-
ed in my paper (’96, @), cast considerable doubt upon this inter-
pretation of the ‘‘sulcus Monroi.”” In any caseit must be borne
in mind that it extends from the aqueduct to the aula and not to
the Recessus opticus as represented in one published figure.

§196. Czmbia.—This architectural term, signifying a band,
fillet or cincture, was"used by me in 1881 in discussing the very
distinct ridge across the crus (cerebri) of the cat before I knew
that it had been called Tvactus peduncularis transversus by Gud-
den (1880) and still earlier (1861) fasczo transverso by an Italian

1My mononym for pars ventriculi communis media,pars foraminis Monrot me-
dia, etc.; 211.

WILpDER, WVeural Terms. 281

anatomist. Unless the first name is to be retained there can be
no logical objection to replacing the second by a third. The
most complete exemplification of the practical superiority of
cimbia is supplied by the section concerning it in the latest
edition of the ‘‘Gewebelehre”’ by the distinguished chairman of
the German committee. On pp. 606-609 (really only three
pages if the cuts be excluded) and in addition to the page-head
and the section-title, Zvactus peduncularis transversus occurs ten
times, occupying more than five fulllines. The occurrence of
Tractus peduncularts in one place, and of TZvactus alone or in
composition with German words in several, shows how burden-
some the polyonym had become, and howirresistible the tempta-
tion to vary. In the explanation of Fig. 707, the full title oc-
curs once; also Zvact. ped and Tr. ped. ; compare §38. Tractus
transversus pedunculi of Brissaud is declared to stand for a differ-
ent bundle, but in the absence of such declaration the two
names would almost inevitably be supposed to mean the same
thing anatomically as they do etymologically. Again, since
Kolliker concedes pedunculi also to the cerebellum (pp. 337, 371,
etc.), and since many anatomists prefer to designate the fibrous
masses between the pons and the optic tracts as the crura, there
is ample opportunity for misapprehension upon the part of the
student, unless, in accordance with the absolute explicitness in-
sisted upon by His (§ 170, s), there be introduced the qualifier
cerebri or cerebralis, All these objectionable conditions vanish
with the adoption of czméza.' Even if this were rejected, ambi-
guity could be avoided and brevity attained by designating the
great fibrous masses above mentioned as crura rather than pe-
dunculi, thus providing for Zvactus cruris transversus, aS sug-
gested in W. and G., ’89, §57, note.

§197.—Jsthmus.—Prof. His complains that this word is
used by mein the sense of Gyrus annectens. This latter term
does not occur in the German list, so I assume that Gyrus trans-
wtivus is meant. No one of my terminologic propositions gives

1That it is not classic Latin, and that it may even have been a corruption of
cimbra, constitute no bar to its adoption into anatomy.

2382 JouRNAL OF COMPARATIVE NEUROLOGY.

me more satisfaction than that of replacing Gyrus annectens,

bridging convolution, and pli de passage, by isthmus when the cor-
tical area is visible at the surface, and by vadum when it is con-
cealed; the occasional interruption of the central fissure is thus
the /sthmus centrals ; that between the adjoining ends of the
parietal and paroccipital fissures, the /s¢hmus parocctpitalts, etc.
So far I cheerfully plead guilty tothe charge. But with what
justice does Prof. His complain further that this employment
of zsthmus is in an ‘‘unusual sense’ when his own list contains
Isthmus gyri forncati? Indeed, even were this complaint well-
founded, it comes with a poor grace from (a2) a German whose
-fellow-countryman (Waldeyer) applied (1891) to the nerve-cell
the term xeuvon, which had been introduced by me (’84) for the
entire cerebro-spinal axis; from (6) a member of the Nomencla-
tur Commission whose chairman (KGlliker) applied (1893) to
the axis-cylinder process of a nerve-cell a term (#ewraxon) practi-
cally identical with one (euvaxis) which occurs in a standard
French Medical Dictionary for the cerebro-spinal axis; and.from
(c) one who himself, upon altogether inadequate grounds," has
made the term in question, zs¢/wmus, of segmental value, and who
has needlessly and unjustifiably modified the scope of prosenceph-
alon and reversed the hitherto commonly accepted sense of
metencephalon; see Table VII.
$198. Medipedunculus.—To this term Prof. His devotes
one-fourth of his entire criticism (§170, ~-2). . Hence some re-
joinder should be made although the objections impress me as
either ill-founded in themselves or inconsistent upon the part of
the objector. Asa word, medipedunculus is no more ‘‘ barbar-
ous” than medttullium,* Mediterranean, or medieval. As a des-
ignation rather than a description, it requires definition. The
beginner would remember medipedunculus quite as easily as
‘‘pedunculus cerebelli ad pontem”’;' and since experienced
anatomists know that there are three cerebellar ‘‘stalks” on
each side but only two ‘‘pedunculi cerebri,’’ one on each side,

1 This term, by the way, does not occur in the German list, where appar-
ently it is replaced by brachium pontis.

Wiper, Neural Terms. 283

he is not likely to infer that either of the latter is meant by
medipedunculus. In fact, this term, as coined and defined by
me,’ is now an idionym, applicable to but a single part of the
brain.

$199. In order to be absolutely explicit and independent
of the context the following terms from the German list should
be accompanied by the words here bracketed after them :—
Chvus [occipitahs|; Chvus | sphenoidahs|; Pars cervicalis
[medullae spinalis |; Sulcus lateralis anterior | medullae oblon-
gatae |; Sulcus hinitans ventriculorum | encephal |; Pars centralts
[ ventricule lateralis |; Ventriculus terminalis | medullae spinalrs |;
Lamina terminalis { encephalr |. The identity of the adjective in
the last two terms would lead the beginner to associate them
topographically, and he certainly would never infer that they
designate parts at opposite poles of the cerebro-spinal axis.’

§200. From the standpoint of Prof. His the foregoing
must be regarded as serious blemishes upon the German list.
From my point of view, although I might object to certain of
the names as such, it would not be on account of their lack of
explicitness. As has been said above (§26) in many instances
explicitness is to be gained from the context. But with really
the larger number, I am confident that well selected, brief, and
fairly suggestive designatory names can and will be learned and
remembered without any difficulty, especially if the study of the
brain be begun at an early age; see Part VIII.

$201. Coelia.—This word, in place of cavitas encephal s.
ventriculus encephal, is one of the three cited by Prof. His (§170,
a) as examples of my many terms that are objectionable be-

1In this connection two remarks are naturally suggested: (1) Medipedun-
culus is an adjectival locative, it and its correlatives, praepedunculus and fost:
pedunculus, constituting one of the most perfect groups of that kind ; #29, 189.
(2) The obtrusively Latin termination of these words, as well as the length of
the words themselves, forced upon me in 1884 (262) the consideration of the
whole subject of paronymy.

2 In the absence of adequate context or prior definition, would any reader
imagine that spongiocyte and spongioplasm refer to elements of the nervous
tissue?

284 JOURNAL OF CoMPARATIVE NEUROLOGY.

cause they are ‘‘new.”’ In the lexicon ot Liddell and Scott
xotdta éyxegddov is quoted as in good and regular standing among
Greek medical writers. According to Burdach (‘‘vom Baue
und Leben des Gehirns,”’ 1819-1822, II, 301, 378, 380), Galen
designated the ‘‘fourth ventricle” as xo:déa éxcoStov eyxegahov,
tetapty xothta and draovla xowhla ( ‘«De usu partium, fap Bric VIEL
C.XII. p. 170); the ‘third ventricle” as péon tpiry xordéa (idem.
IX, III, 172); and the ‘‘lateral ventricles” as zpoodéar xordéat
( ‘‘ De odoratus instrumento,”’ II, 110). Coela is then certainly
not ‘‘new.’’ Had Prof. His said wxusual, his objection would
have been more nearly justified by the facts, although in
recent encephalic literature on both sides of the water com-
pounds of coe/a are more and more frequently encountered.

$202. In favor of coeha (English ce/za or cele)’ in place of
ventriculus may be urged the following:

I. Its Greek origin renders it compoundable regularly
and euphoniously with the characteristic prefixes already em-
ployed in the segmental names, e. g., mesencephalon, etc.

2. These compounds are mononyms and therefore capa-
ble (§47) of inflection, (e. g., mesocoeliae), derivation (e. g.,
mesocoeliana), and adoption into other languages without ma-
terial change; e. g., English, mesocele; French, mesocoele ;
German, Mesokéle ; Italian, mesocelia.

3. The various national paronyms thus formed are like-
wise capable of derivation; e. g., mesocelian.

4. There is classic authority for the use of coe/a in the
sense of encephalic cavity ; §2o1. ;

5. These ancient usages are assumed to be familiar to
educated anatomists, who therefore should recognize the com-
pounds with little or no hesitation.

6. The compounds are so euphonious and so obviously
correlated with the segmental names as to be learned and re-

1 As already remarked (W. & G., ’89, 280, note), in an’ English sentence
the word by itself might be either ambiguous or pedantic and the general term
cavity commonly answers the purpose ; see 248, and (for the replacement of o¢
by ¢) 269.

Wiper, Neural Terms. 285

membered easily even by general students, and by those who
may not have had a classical training.’

7. In recent times it has been independently proposed by
two anatomists, teachers as well as investigators.”

8. It has been adopted more or less completely by three
of the older American neurologists, Henry F. Osborn, (82,
’84, 88), E. C. Spitzka (’81, ’84), and R. Ramsay Wright
(84, °85), and unreservedly by eight of the younger, W.
Browning, I. E. Clark, P. A. Fish, | Mrs: S: PB. Gage,» O;.D:
Humphrey, B. F. Kingsbury, T. B. Stowell, and B. B. Stroud.

$203. It will be noted that among the advantages of coeka
over ventriculus is not enumerated its freedom from ambiguity.
Theoretically, of course, ventriculus (encephal) might be mis-
taken for ventreculus (cardiae s. corde). Practically, however,
the context would almost infallibly obviate misapprehension. *
Hence from my point of view, the absolute unambiguity of
coca and its compounds would not in itself justify its replace-
ment of ventriculus. It would be a causa vera, but hardly a
causa sufficcens.

$204. The concluding remark of Professor His may be
said to ‘‘cap the climax” of his ill-founded criticism. The
characterizations, ‘‘vollig neuen” and ‘‘grossentheils recht
fremdartig Klingenden,”’ could hardly have been more sweeping

1 Among the hundreds of such students at Cornell University and at the
Medical School of Maine who have gained their practical and theoretic knowl-
edge of encephalic morphology by means of these compounds no special diffi-
culty has ever been experienced.

2 My propositions first appeared in the paper, ’81, 4, March Ig and 26,
1881. On the fifteenth of August, 1882, Prof. T. Jeffery Parker read be-
fore the the Otago Institute of New Zealand a paper (’82) in which mesocoele
and similar compounds were introduced, although he was evidently quite una-
ware of my prior publication. The terms were also employed in his ‘* Zootomy”’
(’84) and in a later paper (86).

8My previous reference (2199) to the polyonymic derivative, sudcus limitans
ventriculorum, was not for the sake of demonstrating the ambiguity of that term
but to illustrate the inconsistency of the implied demand of Professor His (3170)
that all terms must be self-explanatory and require no definition.

286 JOURNAL OF CoMPARATIVE NEUROLOGY.

had I proposed to replace Latin by Choctaw.’ Any anatomist,
unprejudiced, and not above conceding the possibility that some
good thing may come out of the American Nazareth, who will
candidly compare the terms in Table VI (Part VII) will admit
that in the second column a comparatively small number are
new in the strict sense of the word, and that the large majority
are either identical with those in the first, or differ therefrom
merely in the omission of useless words, or in the replacement
of adjectives by prefixes of like signification.?

— $205. Comments and criticisms by Prof. A. von Kolliker.
Early in 1892, about a year after the date of the first letters
from the secretary of the German committee (§138) its chair-
man spoke as follows (‘‘ Nervenzellen und Nervenfasern,” Bzo-
log. Centralblatt, XII, 36, Jan. 30, 1892):

**So haben amerikanische Gelehrte im letzten Jahre einen Ver-
such zur Verbesserung einiger Teile der anatomischen Nomenklatur
unternommen, und hoffen wir, dass dieselben unserer Einladung zu
gemeinsamer Arbeit entgegenkommen werden. Sollte es gelingen,
wenigstens die lateinischen Namen in den morphologischen Wissen-

schaften zu einem Gemeingute aller zu machen, so ware hiermit offen-
bar ein grosses Ziel erreicht.”

$206. Following is a translation of the above:

‘‘ During the past year American scientists have made an effort
toward the improvement of some parts of Anatomic Nomenclature.
We hope they will look favorably upon our invitation to join us in our
work. Should we succeed at least in making the Latin names in the
morphologic sciences common property, a great end would thereby be
attained.” F

$206. The foregoing implies that the codperation of
American anatomists not only was desired but had been asked.
I am not aware that other members of the American commit-

1At that time, although my principal article on terminology had not been
read by Professor His (see Part VI), the lists of terms preferred by me were in
his hands (?140, note), so that no claim can be entertained that he referred
merely to what he assumed my proposals ‘‘ tended ”’ to bring about.

2Just as this goes to the printer (Nov. 13, 1896) there reach me several re-
prints of the note by Professor His in the Amat, Anszeiger (XII, 446-448, Novem-
ber, 1896) entitled “‘Herr Burt Wilder und die Anatomische Nomenclatur.”
His remarks will be considered in connection with our correspondence, Part VI.

WILDER, WVeural Terms. 287

tees corresponded with members of the German committee upon
the subject of anatomic nomenclature, and the request of Dr.
Krause for our reports and for my papers could hardly be inter-
preted as an official invitation to cooperate; see $137.

$207. So faras I am aware, the only other utterance of
Prof. Kolliker upon the subject constitutes a paragraph on p.
814 of the second volume of his ‘‘Gewebelehre”’ in the part
which was published, I believe, in the spring of 1896. It is as
follows:

‘‘Die Nomenklatur anlangend, habe ich mich selbstverstandlich in
diesem §, wie in dem ganzen Buche, an die bekannten Beschliisse der
Kommission der anatomischen Gesellschaft und den Vomenclator ana-
tomicus derselben gehalten. Die in den letzten Jahren von Amerika
ausgehende anatomische Nomenklatur halte ich fiir vollkommen ver.
fehlt und fiir so unverwendbar, dass es mir unmdglich ist, Abhandlun-
gen zu lesen, denen dieselbe zu Grunde gelegt ist. Man kann doch
von einem Gelehrten, der eine ordentliche Schulbildung genossen hat,
nicht verlangen, dass er die vielen Barbarismen dieser Nomenklatur,
wie metatela, metaplexus, auliplexes, diaplexus, ectocinerea, cephalad, caud-
ad, dorsad, cephalo-dorsad, ventro-caudad, dorso-caudad, hemtcerebrum u.
s. w. ruhig annehme und bei einer grossen Anzahl anderer Worte, wie
terma, proton, pero, prosoterma, dtaterma, supraplexus, aula, alba, crista,
diacoele, mesocoele u. s. w. erst hingehe und lerne, was dieselben
bedeuten sollen. Als altester deutscher Anatom wird es mir wohl er-
laubt sein, den amerikanischen Kollegen den Rath zu geben, auf die-
ser Bahn nicht weiter fortzuschreiten, sonst wiirde es im Laufe von
einigen Jahren dazu kommen, dass man sich hiiben und driiben nicht
mehr verstiinde und jeder wissenschaftliche Verkehr unmédglich
wiirde.”

§208. Following is the translation:

‘*As regards nomenclature I have of course maintained in this sec-
tion, as in the whole book, the known conclusions of the committee
of the anatomische Gesellschaft and the omenclator anatomtcus there-
of. The anatomic nomenclature coming from America in recent
years, I regard as a complete failure, and as unavailable, because it is
impossible for me to read articles based thereon. One cannot ask of
a scholar who has received an accurate education that he accept
quietly the many barbarisms of this nomenclature, such as metatela,
metaplexus, auliplexus, diaplexus, ectocinerea, cephalad, caudad, dorsad,
cephalo-dorsad, ventro-caudad, dorso-caudad, hemicerebrum, etc. and with
a great number of other words like ¢ervma, proton, pero, prosoterma,
diaterma, supraplexus, aula, alba, crista, diacoele, mesocoele, etc. first go
to work to learn what they mean. As the oldest German anatomist,
it may be permitted me to advise our American colleagues not to con-
tinue farther in this direction lest, in the course of a few years, it come

288 JouRNAL oF CoMPARATIVE NEUROLOGY.

about that we cannot understand each other in the two countries, and
hence all scientific intercourse will become impossible.”

§209. The age of Prof. Kolliker, his magnificent services
in the advancement and diffusion of science, and the evident
sincerity of his regret at American departures from what he re-
gards as terminologic rectitude, all demand serious rejoinder.

$210. Among the terms that one must ‘‘ go to work to
learn what they mean,” c/zsta ( fornicis ) designates a feature of
the brain which, so far as I know, was first described by me in
1880 (’80, g; W. & G., 82, §1214; Mrs. Gage, ’93, 283-284);
as its discoverer, I may be permitted to assign ita name. evo
was proposed by me (’81, 0) for the soft ectal layer of the
Bulbus olfactorius which, in hardened animal brains, often peels
off the firmer ental ‘‘ core”’ like a boot; but the word is seldom
needed. If the ¢erma ($194) pertains to two encephalic seg- |
ments, dzaterma and prosoterma seem to be both appropriate and in-
telligible. JZesocoele and diacoele (Latin, mesocoelia and diacoela;
English, mesocele and dracele) have been discussed directly or
indirectly above (§201-203). Swpraplexus, (introduced, I think
by Mrs. Gage ) would certainly be supposed to indicate a plexus
in the roof of some part of the brain cavity. Alba could
hardly suggest anything else than the substantia alba of the Ger-
man list; see $116.

S211. Aula.—After years of confusion, doubt, and even
distress of mind, induced by the failure to reconcile the facts of
development and comparative anatomy with the prevalent
nomenclature of the brain, in 1880 (’80, d, ¢, f; ’81, 6, d) I
proposed av/a upon grounds formulated two years later as fol-
lows (W. and G., ’82, $1065) :—

(1) ‘*To substitute brief single words for the phrases, ‘‘ventricu-
lus communis,” ‘‘ventriculus lobi communis,” mesal part of the
‘*common ventricular cavity,” ‘‘ foramen Monroi,” ete.

(2) Because the phrase most commonly employed, /oramen
Monrot, is used to designate at least three different cavities or orifices:
(a2) The cavity by which either paracoelia [‘‘ lateral ventricle ”’] com-
municates with the mesal series of cavities; (4) The two lateral ori-
fices together with the intervening space; (c) The mesal [ cephalic ]
orifice of the diacoelia. We have been unable to ascertain by whom

¢

WILpDER, Neural Terms. 289

the phrase was first employed, and the description by Monro secund-
us (1783), in whose honor it was applied, is somewhat vague.

(3) In order to indicate our opinion of the desirability of
recognizing the aula as morphologically an important element of the
series of encephalic cavities.”!

$212. Proton.—This neuter noun was used by me (’93, a,
$46, note) to designate the comparatively undifferentiated mass
in which two or more parts might afterward be distinguishable.
It is free from certain obvious and by no means inconsiderable
objections that may be brought against Azlage and fundament
as English words. It is subject to inflection, and may be
adopted into any language. In many derivatives or compounds
it is associated in the minds of all educated persons with the
general idea of primitiveness. Its employment is in harmony
with the following phrases from Aristotle cited for me by Prof.
B. I. Wheeler:—t0 zp@tov; 4 xewty BAn; 4 cpwTy aitia,

$213. In short, all my regrets for the errors already con-
fessed (§ 71) and for others of which I may be convicted, to-
gether with all my doubts regarding certain of the terms not as
yet acted upon by the American committees, shrink into the
background of my mind as I reflect upon the nature and signifi-
cance of aw/a and proton, and upon the advantages that have
been and may be gained from their employment.

$214. In the foregoing extract (§207) I suppose ‘‘Barbar-
ismen’”’ means verba hybrida, i. e., words formed by the con-
junction of Latin and Greek elements. If so, one of the six
specified organonyms, viz., auliplexus, must be exempted from
the stigma since aula, although derived from the Greek aij
is a Latin word in good standing. To the remaining five I add
five other neural mononymic hybrids for which I am respons-
ible. Ina parallel column of Table IV are given the equivalents
either as in the German list or as they would be regularly form-
ed. In another (the first) column are placed an equal num-
ber of hybrid words selected from the German list, and hence,
I infer, sanctioned by the President of the Commission. With

1 With some of the lower vertebrates (e. g., Chémaera, ’77, a,) the aula is
much more extensive than either of the ‘‘lateral ventricles” with which it is
connected through the two portae.

290 JOURNAL OF COMPARATIVE NEUROLOGY.

both groups I have italicized the Greek element which (so far as
appears in a standard lexicon) failed to be adopted (by paronymy)
into classic Latin. Of course the abstract etymologic immor-
ality involved in the two sets of irregular connections is the
same. The offspring of the second set surely compare favor-
ably with the first in point of comeliness,' and their utility as
savers of labor and time may be estimated by comparison with
their polyonymic equivalents in the third column.

TABLE ILy.

Hybrid words con-|| Hybrid words for| Polyonymic equivalents of the words in
tained in the Ger-|| which thewriter| the second column, mostly from the Ger-
man List. zs responsrble, man List.

Lpidurale Metatela “Lamina chorioidea epithelialis”’ [ven-

triculi quarti]

Mesovaricus Diatela ‘Lamina chorioidea epithelialis ”’ [ven-

triculi tertii]

Parumbilicales Paratela ‘* Lamina chorioidea epithelialis ” [ven-

triculi lateralis]

Parolfactorius Metaplexus ‘¢ Plexus chorioideus ventriculi quarti”

Perichoriotdiale Diaplexus ‘a $s os tertii ”’

Suprachorozdea Paraplexus ss aS ee lateralis”

Choriocapillaris Ectocinerea *¢ Substantia corticalis”

Prerygopalatinus Entocinerea “¢Stratum griseum centrale ”’

Prerygomandibularis|| Zemzcerebrum |Dimidium cerebri laterale

Phrentcocostalis Hemiseptum Dimidium septi pellucidi laterale

$215. The reasonable view of hybrid terms seems to me to
be embodied in the following remark of Barclay ('03):

‘‘Notwithstanding the opprobrium attached by some to certain con-
nections and intermarriages among harmless vocables, I should be in-
clined not to reject the codperation of the two languages (Greek and
Latin) where experience shows it to be convenient, useful or neces-
sary.”

Abstractly, we may all prefer horses to mules, but this need
not hinder us from recognizing that, under certain circumstances,
the latter are more efficient than the former, and that, ina given
case, a horse may not be even so handsome as a mule.

$216. The verdict of Prof. Kolliker that the nomenclature

coming from America in recent years is a ‘‘complete failure”’

'The first four from the German list might have been replaced from the same
source by the less acceptable ‘‘sphenopalatinum,”’ ‘‘sphenodccipitalis,” ‘‘occi-
pitomastoidea” and ‘‘squamosomastoidea.”’

Wiper, Neural Terms. 291

because he cannot read the articles based thereon, approximates
what has been called ‘‘the erection of the limitations of one’s
individual experience into objective laws of the universe.” I
sincerely trust that he may some day concede the validity of
these two propositions:—(1) A considerable number of investi-
gators and advanced instructors on both sides of the ocean have
employed the ‘‘American” system more or less systematically.
(2) Judging from my own experience as learner and teacher,
the hundreds of students, general and special, upon whom that
system has been practised since 1880, have either saved so much
time, or gained so much more information within a given time,
as to make its employment ‘‘worth while’ even when the later
environment proved unfavorable to its permanent use.

$217. In concluding this response to the criticism of ‘‘the
oldest German anatomist’’, I venture to call his attention to the
different reception accorded my plans for terminologic simplifi-
cation by two other anatomic teachers well advanced in years,
viz., Joseph Leidy (§ 56, note) and Oliver Wendell Holmes
($79). In order also that I may not appear unmindful of the
fact that the assimilation of verbal novelties becomes less easy
with increasing age,’ I reproduce the concluding paragraph of
my second paper upon the subject (’81, 0):

‘‘The beginner can learn the new terms even more easily than the
eld, and at any rate he has nothing to forget. But the trained ana-
tomist shrinks from an unfamiliar word as from an unworn boot; the
trials of his own pupilage are but vaguely remembered; each day there
seems more to be done, and less time in which to do it; nor is it to be
expected that he will be attracted spontaneously toward the consider-
ation that his own personal convenience and preferences. and even
those of all his distinguished contemporaries, should be held of little

moment as compared with the advantages which reform may insure to
the vastly more numerous anatomical workers of the future.”

1The argumentum ad hominem is ungracious at the best, and the occasions for
its employment in this paper have been too numerous already. But when I re-
call the delay and mystification inflicted upon me and my students by the va-
riety and heterogeneity of terms, Latin and vernacular. with which most German
treatises upon encephalic anatomy literally bristle (22 58-60, 169, note), I can-
not but feel that, however sincere may be the repentance therefor among the
anatomists of that nation, the needed reform should have been practised for a
somewhat longer period before others were rebuked.

292 JOURNAL OF COMPARATIVE NEUROLOGY.

§218. Under the limitations of time, space and compe-
tence, I have now responded to the criticisms of the Anatom-
ische Gesellschaft, the German committee, and three individual
members thereof. However unfounded, unwise, or even unjust
some of those criticisms may appear to me, I am disposed to
believe that they were prompted by a wish to further what the
critics regard as the best interests of anatomic science. They
will, therefore, I trust, credit me with a similar motive in urging
upon them as anatomists, and especially as German anatomists,
the earnest consideration of one of the topics discussed in the
earlier portion of this paper, viz., Paronymy as opposed to Het-
eronymy (S$ 43,85, e).

§ 219. Unfortunately, upon this point (which seemed to
me in 1885 so important that it was the subject of my address
as president of the American Neurological Association ’85, c) I
find myself unable as yet to determine what view is held by the
German committee. Its secretary has declared ($159, 4) ‘‘that
each nation can translate the Latin (international) name after its
own fashion ;” also (§ 158, 1) that German designations [hetero-
nyms] in so far as they are not already established, or so far as
they are really necessary, are left to the free choice of the indi-
vidual.

$220. Whatever be the real or intended purport of the
foregoing, the latest publications of the chairman of the commis-
sion (‘‘Gewebelehre’’), and of the member who has most fully
discussed the subject, contain many and even diverse German
vernacular equivalents of the Latin terms recommended by
them. The article of Prof. His ('95, @) yields at least a score of
such which have no etymologic relation with the Latin terms.
It seems to me that, with the exception of Gezrn and possibly
a few others (§ 48), the systematic employment of paronyms
(§ 46) would greatly facilitate the comprehension of German
writings by anatomists of other nationalities, and especially by
students, without materially embarassing the Germans them-
selves.

Some of the Latin
terms adopted by
the Amer. Neurol.

Wiper, Weural Terms. 293

$221. The feasibility of this method was exemplified in
some degree in 1889 upon the ‘‘Table of Paronyms” (W. &

Asssoctation.

I
2

5
4
5
8
9
) Ke)
II
12
13
14

25

16|F, hippocampi

17

18
Ig

20
21
22
=)

24
25
26
27

28
29
30
31
32
33
34
35
36

Calcar
Callosum
Chiasma
Claustrum
Clava
Cuneus
Dentatum
Dura
Epiphysis
Falx

F. calcarina
F. centralis
F. collateralis

Fornix

Hippocampus
Hy pophysis

Infundibulum
Insula
Lemniscus

Mesencephalon

Monticulus
Oblongata
Oliva
Operculum

Pallium

Pia

Pons
Praecuneus
Pulvinar
Striatum
Tegmentum
Tentorium
Thalamus

TABLE Y.
Examples of the use of these paronyms,
German paronyms. or of analogous ones, by German
writers.
Kalkar Kalkig
Kallosum s Callosum
Chiasma ‘‘Chiasmas” (Onufrowics, ’87, 12)
Claustrum “‘Cerebellumgebiet” (His, ’80, 26)
Clave Olive
Cuneus
Dentatum ‘‘Ablegat.”
Dura s. Dur
Epiphyse Krause, 779, 780
Falx
Kalkarinfissur
Centralfissur “‘Centralcanal”’? (Henle, ’79 231.)
Collateral fissur “‘Collateralfurche’”’ (Wernicke, ’82, I,
I
Hippokampalfissur
Fornix ‘‘Fornixtaenien’’(His, ’95, 167) ‘‘For-
nixschenkel”’ (Schwalbe, ’81, 464)
Hippokamp
fAlypophyse ‘‘Hypophysenblase” (Schwalbe, ’81,
477)
Infundibulum eC crabellmpebeie? (His, ’80, 26)
Insel (Henle, ’79, 170)
Lemniscus

Mesenkephal s. Mesen-/‘Rhinencephalons”’ (His, ’95, 175)
cephalon

Montikel “‘Follikel’”’ (Schwalbe, ’81, 473)

Oblongat Advocat

Olive ‘‘Nebenolive” (Schwalbe, ’81, 615)

Operculum “des Operculums,” Jen. Zettschr.,
XXIX, 25

Pallium “des Spleniums”

Pia ‘‘Piaplatte’’ (Edinger ? ?)

Pons ‘“‘Ponsfasern” (Edinger ’89, 153)

Pracuneus

Pulvinar

Striatum s. Striat ‘‘Ablegat”’

Tegmentum s. Tegment |«*«Moment”’

Tentorium

Thalamus “Thalamuskern” (Schwalbe, ’81, 711)

G., ’89, 530-531). Inow venture to offer in Table V what
seem to me appropriate German paronyms of most of the Latin
terms adopted by the American Neurological Association ($80).
So far as possible either the actual paronyms, or analogous pre-

294 JoURNAL OF COMPARATIVE NEUROLOGY.

cedents therefor, have been’ selected from German writings. In
the other cases the suggestions may not be always well-founded.

Part VI. Correspondence with Professor Wilhelm Fits.

§222. The general occasion for the existence of this Part
was stated in the Introduction, §4. The hope, entertained at
the time that was written and expressed at a later period ($171),
that Prof. His might publicly correct all his errors of omission
and commission, has not been realized in his article (just re-
ceived in the Avatomischer Anzeiger, XII, 446-448, Nov., 1896,
hence the correspondence is most regretfully submitted. The
only changes consist in the omission of unessential paragraphs,
and in the addition of notes, or of words in brackets.

§223. From the writer to Prof. His, Dec. 3, 1895.

Prof. W. His, Dear Sir:—Not until a week ago was able I to read
your article in the Archiv f. Anatomie etc., 1895, ‘* Die anatomische
Nomenclatur,” wherein, on pages 6 and 7, you do me the honor to
discuss my views especially with reference to encephalic terms.

It is my intention to present the subject at the coming meeting of
the Association of American Anatomists, on the 26th of this month,
and before doing so I desire to obtain from you answers to the sub-
joined queries. It will be a favor to me if the answers, or as many |
as possible of them, can reach me before the meeting, and it will be
an advantage to our discussions if you permit them to be made
public.

Regretting to differ with you, and to ask you to perhaps incon-
venience yourself in order to reach me in season, I have the honor to
remain, Very respectfully yours,

Burt G. WILDER.

1. I see no reference to the writings of Richard Owen or Pye.
Smith. The latter (Jour. of Anat. and Physiology, Oct. 1877) pub-
lished an article of 22 pages and insisted upon the sufficiency of thala-
mus which you concede. The former introduced fostcava and precava
and (‘‘ Anat of Vertebrates,’’? III p. 136) gives a list of fissures, all
the names being mononyms and some (cal/osal, supercallosal and sub-
Jrontal) apparently unobjectionable. Why were these not included in
the column of synonyms by ‘‘ various authors” [in the protocols of
the committee ? §178, 3].

2. Excepting some compounds of excephalon, nearly all the mono-
nyms upon yourlist of encephalic terms, about twenty-five in num-
ber, had already been selected and adopted by me. Was not this

Witpver, WVeural Terms. 295

coincidence worth mention as indicating the possibility of some degree
of harmonious codperation between us?

3. You say ‘‘ Wilder und seine Collegen verlangen lauter Mon-
onyme.” This is correct [but only in the sense of. prefer; see $172].
You then add, ‘‘Sie sagen, z.B. praecornu, pdstcornu und fpostcava.”
These words are used by me, but not, so far as I know, by other
members of the American Committees,! although they recommend the
employment of CALCAR for Atppocampus minor, HIPPOCAMPUS for A.
major, PONS for pons Varolit, INSULA for insula Retlii, and PIA and DURA
for pia mater and dura mater respectively.

4. You refer to the principle of mononymy. But you do not
seem to have gathered, even from my ‘‘ Paronymy versus Heterony-
my as Neuronymic Principles” [85, ¢], that mononyms are preferred
by us to polyonyms not so much because they are usually shorter, but
because, whatever their length, they are capable of two desirable
modifications, vz., (a) inflection as adjectives (e g., thalamicus, callos-
alts, duralis, etc.) and (4) adoption by paronymy into other languages,
(e g, hippocampus, hippocampe, hippocamp, Hippokamp, hippocampo).
Am I to infer that this feature of the matter was unknown to you,
or regarded as slight in importance ?

5. You say ‘‘Sprachwidrige Wortzusammensetzung enthalt aber
Wilder’s Liste sehr viele”? It would not be without probability or
precedent that errors should occur among so large a number of terms,
but I must insist upon the specification of my ungrammatic verbal
combinations In particular I ask fuller grounds of objection to med-
ipedunculus |S198]

6. You mention certain papers by me [as ‘‘eine Reihe von
kleineren Aufsatzen und Broschiiren” ; $170, d, note 2]. Their few-
ness [four], their brevity, and their recent dates [1890-1892] would in-
dicate that T had done little on the subject and that my views are cor-
respondingly unimportant. Yet my first paper on [encephalic] Nom-
enclature was in 1880 and I have published something almost annual-
ly since upon it. The article |W. and G, ’89] in the ‘‘ Reference
Handbook ” [of the Medical Sciences, VIII, 515-533, 1889] was, so
far as I know, the fullest discussion of late years; a copy was sent to
Dr. Krause [secretary of your committee] about May, 1891, and his
letter of April t2yarg92, informed me that it had been ‘‘set in circu-
lation among the Committee.” It is also mentioned in most of my
papers or documents printed since 1889. In 1892, the American As-
sociation for the Advancement of Science adopted unanimously the
Report of the Committee (of which I am not a member) on Biological

1As stated in the Introduction, #3, I desire to free others from responsi-
bilities which they have not assumed. So far as may be inferred from the entire
absence of later reference to this point upon the part of Professor His, an alle-
gation, absolutely unfounded and casting upon several American anatomists what
they may regard as serious discredit, may be publicly made and neither sub-
stantiated nor withdrawn.

296 JouRNAL OF COMPARATIVE NEUROLOGY.

Nomenclature [§85, 7, and note? ], including a characterization of the
Handbook article ‘‘ as representing an epitome of the whole subject,
with suggestions for future progress.” A copy of that Report was
sent to you. Is your absolute silence as to the article to be interpreted
as indicating that you not only never saw it, but never heard of it, or
had no idea of its scope?

§224. From Professor His to the writer, Dec. 15, 1895.

SEHR GEEHRTER HERR CoLiecE: Ihr Brief vom 3d M. mit den 6
fragen trifft erst heute bei mir ein, und es ist mir zweifelhaft, ob meine
Antwort bis zum 26 in Ihren Handen sein kann. Ohne in Einzeln-
heiten einzutreten, was wohl ziemlich nutzlos sein wiirde, hebe ich
hervor, dass es sich in dieser Sache nicht um eine persdnliche Angel-
egenheit handelt, da die anatomische Gesellschaft als solche zu Ihren
Bestrebungen Stellung genommen hat. Sie finden die Erklarung der
anatomischen Gesellschaft im Bericht [etc.; see this article $147].

Hochachtungsvoll Ihr ergebener, W, His:
§225. Translation of the above letter from Professor His,
Deew15, 1895.

ESTEEMED COLLEAGUE: Yours of the 3d containing six queries
was received to-day and I doubt whether my answer can reach you for
the 26th. Without entering into details, which would very likely be
useless, I point out that this is not a personal matter, since the Ana-
tomische Gesellschaft as such is opposed to your efforts. You will
find its declaration in the Report, etc. [see $147 of this article].

Respectfully yours, W. Hus:

§226. From the writer to Professor His, Jan. 3, 1896.

ProFessor His, DEAR SiR: Your favor of Dec. 15th reached
Philadelphia after the close of the last session of the Association of
American Anatomists. J infer that you had no objection to tts publica-
tion. Pray accept my thanks for your promptness, and for the ref-
erences to the published opinion of your committee. This I was ac-
quainted with. It is practically a declaration of conservatism which
I hope to find time to comment upon. I conclude that you regard
the queries in my communication of Dec. 3, 1895, as covered by the
committee’s opinion. Whatever view might be taken as to the first
four, I feel justified in calling upon you personally for explicit re-
sponses to the last two, vz.:—What ‘‘ ungrammatic verbal combina-
tions” occur in my recent lists? What explanation have you for in-
timating that my first publication on Anatomic Nomenclature was
dated in 188g instead of 1880, and for ignoring the article ‘“‘ Anat.
Terminology” in the ‘‘ Reference Handbook of the Medical Sciences,”
1889 ?P

The immediate question is, What is due to those continental
anatomists who, in the absence of my lists of terms or of the publica-
tions by myself and other Americans who have more or less complete-

WILpER, Weural Terms. 297

ly adopted them, may have been unduly influenced by the absence of
those terms from the Committee’s lists of synonyms, and by the seri-
ous omissions and errors embodied, however unintentionally, in your
article ?

It seems to me not too much to ask of you to supply the oppor-
tunity for independent comparison and judgment by reproducing in
your Archiv the accompanying List of Neurologic and Vasal Terms
adopted by your Committee, the terms preferred by me in parallel
columns, the accompanying commentaries by me and such as you may
think best to add, and the correspondence of which this forms a part.

I have the honor to remain, Very respectfully,

Your obedient servant, Burt G. WILDER.

§227. The further correspondence between Professor His
and myself was as follows :—Second letter from him, Feb. 29,
1896. Third from me, Aug. 11. Third from him, Aug. 27.
Fourth from me, Sept. 28. Although my third contained the
statement that I was editing our correspondence for publication,
and the third from Professor His offered no objection thereto,
after consultation with the editors of this journal it has been
deemed best to summarize the later letters, and to include the
article (His, ’96) already referred to (§222). As indicated at
the outset of my second letter (Jan. 3, 1896; $226) I felt that
he had tacitly granted my request for permission to publish his
first letter (§224).

§228. At this stage I should like it understood that, in
originally addressing Professor His directly rather than in the
columns of a journal, I had two motives, vzz., Furst, the belief
that the impending discussion of Anatomic Nomenclature by
the Association of American Anatomists would be facilitated
by the information sought. Secondly, the sincere desire to avoid
a public controversy by affording to one whom I regarded as
mistaken the opportunity to modify his statements voluntarily.
This desire was in accordance with the sentiment, long enter-
tained, but first expressed six years ago in this journal (’91, 4,
201-202) that, ‘‘since everyone makes mistakes, the interests of
all concerned would be best subserved by the adoption of the
custom of each correcting his own, either as soon as discovered
or periodically ; a sort of scientific confession of sins. The
natural corollary to this would be that each well-disposed dis-
coverer of another’s faults would inform him privately so that
he might make prompt correction. This plan I have followed in
several cases, and have reason to believe it has served to avoid
personal irritation and the needless repetition of criticism.’”

1 The lamentable failure of the plan in the present case does not lessen my
confidence in its essential soundness.

298 JOURNAL OF COMPARATIVE NEUROLOGY.

§229. The second letter of Professor His contained no re-
plies to my questions, and evinced no disposition to discuss the
subject publicly ; on the contrary it declared that he had given
up all connection with nomenclature, and preferred to devote
his time to other studies.

$230. In order to appreciate the situation from my stand-
point there should be borne in mind certain facts, and certain
propositions that are unlikely to be contested:—(a@) Pro-
fessor His not only originated the German movement for
a revised nomenclature, but was a member of the special
committee of three on the ‘‘ Redactionsausschuss ;” (0) he
had set forth the aims, methods and results of the entire
committee in an extended article ; (c) having assumed such re-
sponsibilities, it was his duty to ascertain what had been done
already ; (2) had my own labors been wholly ignored I should
have contented myself with my associates in this respect, Bar-
clay, Whewell, Owen, Pye-Smith, and others; (e) but, in con-
nection with a somewhat extended animadversion upon my
views, what purported to be a list of my ‘‘chief publications”
upon nomenclature omitted that which was most comprehen-
sive; (/) under date of April 12, 1892 ($142), the secretary
of the German committee had assured me that a copy of my
principal article had been set in circulation among the members
of the committee ; (g) inquiries dated Dec. 1, 1895 and July
10, 1896, as to whether it had actually been transmitted to Pro-
fessor His, remained unanswered by the secretary; (/) the last
of the six inquiries accompanying my first letter (§223, 6) might ~
have been answered at once and ina single word; (2) there
would then have remained merely the explanation of his non-
acquaintance with the article in question.

§231. On the eleventh of August, after waiting. five
months in the hope that reflection might convince Professor
His that his previous letters did not meet the fundamental require-
ments of the situation, I reminded him that the six points at
issue between us fell into two distinct categories ; that points I,
2 and 4 (indicated by the sections so numbered in my first
letter) called for the exercise of a certain amount of profess-
ional courtesy, and that he was clearly within his rights in de-
clining to take the time required for their elucidation; but that
the other three had no necessary connection with nomenclature,
and that courtesy need not be invoked in dealing with them.
He had brought a general indictment, wzz., as to the existence
of ‘‘ many ungrammatic verbal combinations in my lists” (§223,

WILDER, WVeural Terms. 299

5), and he was bound to furnish specifications. He had uttered
a charge (‘‘ Wilder und seine Collegen verlangen lauter Mono-
nyme,’’ §§172, 223, 3) which was either ambiguous or unfounded,
and he was bound to explain or withdraw it. While undertak-
ing to enumerate my ‘‘ hauptsachlichste Schrifte,” he had failed
to mention the principal one, and he was bound to account for
either his ignorance of the facts or for his failure to state them.

§232. To this Professor Hisreplied under date of Aug.
27. His sentiments are expressed in his article (His, ’96)
of the same date published two months later. The original is
readily accessible, but a translation is here appended.

‘“« Mr. Burt Wilder and Anatomic Nomenclature.
By Wilhelm His.

Some time after the publication of the Nomenclature adopt-
ed by the Anatomical society at Basel, Professor Burt Wilder
of Ithaca, N. Y., U. S. A., complained to me by letter concern-
ing the manner in which his own efforts at simplification of ana-
tomic nomenclature had been mentioned in the introduction to
the BNA” Mr. Wilder clothed his complaints in the form
of personal questions and furthermore expressed the desire to
publish my answers at the same time with his questions. This
is a somewhat inquisitorial proceeding, unusual hitherto in in-
tercourse among scholars. In the present case, also, the
question is not a personal difference between Mr. Wilder and
myself but concerns matters that have had their formal settle-
ment through the transactions at Basel. Moreover, the ana-
tomical society has stated its views respecting the efforts of the
American Nomenclature committee in a special declaration,
signed by all the members of the commission’ and by the Pres-

1 With the exception of this article by Professor His, all of the translatiuns
of German extracts and letters in the present paper have been kindly revised by”
my friend Fraulein Berthe J. Bartelmann, Instructor in German at Smith Col-
lege, Northampton, Mass.

? Explained in a note upon the reverse of the title leaf of His, ’95:—‘‘ Als
abgekiirtze Bezeichnung der in Basel angenommenen Nomina anatomica wird
vorgeschlagen [ BNA]’’.

3 Proceedings of the Anatomische Gesellschaft, at the ninth meeting at Basel,
edited by K. v. Bardeleben, Jena, 1895, p. 162. [It is doubtless through an
oversight that this statement is not here qualified by the phrase, ‘‘ present at
Basel,” as in the report quoted in 3147. Of the eighteen members of the com-
mittee, nine were then present ].

300 JOURNAL OF COMPARATIVE NEUROLOGY.

ident of the Society. In concert with my colleagues on the
editorial committee, the Messrs. Waldeyer and W. Krause, I
have refused consequently to answer the separate questions of
Mr. Wilder, and have referred him to the above mentioned
declaration. Likewise, I had to refuse a later and unreasonable
demand to print in the Archiv fur Anatomie u. Physiol. his brain-
terms together with those of the BNA. My colleagues and
I were of the opinion that such a proceeding is not incumbent
upon me, and that Mr. Wilder should be asked to present his
amendments to the special revision committee of the Anatom-
ical Society.

‘¢A letter just received from Mr. Wilder, very objection-
able in its form, shows me however that he believes himself to
have been injured by me through the intentional ignoring of
his earlier publications reaching back to 1880, as well as his
more comprehensive article, ‘‘ Anatomical Terminology,” in
the ‘‘Reference Handbook of the Medical Sciences,” VIII,
T8890, p. 515-533.”

‘¢To that I feel it my duty to offer an explanation. I cited
such of Mr. Wilder’s papers, with the qualification as the most
important, as at that time were at hand. The ‘‘ Reference
Handbook,”’ little known in Germany, has never been in my
hands, and by mischance the separate proof-sheets of the article
referred to, which Mr. Wilder had sent to Mr. Krause in the
year 1891 with a view to the information of our committee at
that time, has not reached me. It was, Mr. Krause informs me,
lost by one of the members. Indeed, I was not aware of the
existence of this treatise when I wrote the introduction to the
BNA., and an intentional neglect of the same is out of
the question.

‘‘In order however to avoid all reproach of injustice to-
ward Mr. Wilder I present herewith his questions in the form
revised by him [ $223, 1-6]. Each reader has then the basis
for independent judgment.

Saasgrund, Ct. Wallis, Schweiz, 27 August, 1896.”

§233. To the letter written at the same time as the fore-
going article I replied (Sept. 28) that the plainess and peremp-
toriness of my previous communication might have been avoided
had my earlier letters received due consideration. There has
emanated from Professor His no sign of regret for his omis-
sions. his errors, or his delay in their rectification.

Witver, Neural Terms. 301

Part VII. List of the Neural Terms, about Five Hundred and
Forty in Number, Adopted by the Anatomische Gesell.
schaft in 1895, together with Those now
Preferred by the Writer.

$234. The special names are arranged in seven groups, corre-
sponding with the six definitive encephalic segments (see Table VII)
and the myelon (spinal cord). In accordance with the general rule the
series begins with the first (most cephalic or ‘‘ anterior”?) segment, and
ends with the myelon.

$235. First Column.—-These names are as in the German list
published by Prof. His (’95, a, 80-87), excepting as follows :—(a@) Some
typographic errors may have escaped detection. (4) It was found im-
practicable to reproduce the original ‘‘ middle heads” in their various
typographic forms; so far as possible, however, the subordination of
less to more comprehensive terms is indicated by ‘‘ indents.” (c) In
addition to words, mostly genitives of proper names, bracketed in the
original, there are here introduced in brackets some entire terms to
facilitate the recognition of certain parts apparently not specified in
the German list.

$236. Second Column.—These are the Latin terms now preferred
by me. In some cases I have been in doubt as to the identity of parts
indicated in the German list; in others as to the desirability of any
designation at all. The capitalized names are those respecting the ex-
cellence of which, both as designations and as terms, I feel most fully
assured.

$237. Zhird Column.—This contains the English forms, or An-
glo-paronyms, of the Latin terms preferred by me. Often they are
identical therewith, and in all cases the differences are so slight as not
to hinder their recognition; §$44-48.

$238. Last Column.—The signs refer to the adoptions of the Latin
terms in the middle column. (a) The word gemeral signifies that the
term is in common use. (4) The capitals N., G., A.,5., signify the
formal adoption of the terms by the American Neurological Associa-
tion (1896; §80); the Anatomische Gesellschaft (1895; $137); the
Association of American Anatomists (1889; $81); and the American
Association for the Advancement of Science (1892; $84). (c) The
dates, ’80-’96, are those of my own adoption of the terms in the mid-
dle column; see Part II and the Bibliography.

302 JOURNAL OF COMPARATIVE NEUROLOGY.

TABLE VI.
Termini Neurologici Generales.

German Committee. Present writer. Angloparonyms. | Adoptions,
1|Nervus NERVUS Nerve General
2|/Ganglion GANGLION Ganglion General
3|Substantia alba ALBA Alba ’80; 2116
4|Substantia grisea CINEREA Cinerea itefoy) OC
5|Substantia gelatinosa |GELATINOSA Gelatinosa 96
6|Taenia telarum RIPA Ripa SI
7|Ependyma _ ventriculo-[ENDYMA Endyma "81

rum
8|[Liquor cerebrospinalis]};COELIOLYMPHA _ |Celiolymph 89
9|Sulcus limitans ventric-|Sulcus interzonalis Interzonal sul-|’96; 3195

ulorum cus.

1o|/Nuclei nervorum cere-|Nidi Nidi "89; 4123
bralium
11|Nuclei originis Nidi originis Nidi of origin |’89
12|Nuclei terminales Nidi terminales Terminal nidi_ |’89
13/Ramus communicans |RAMUS COMMUNI-|Communicating |General
CANS ramus
I4;/Ramus anastomoticus ;|RAMUS ANASTO-/Anastomotic ra-|General
} MOTICUS mus.
15|Nervus cutaneus NERVUS CUTAN -/Cutaneous nerve|General
EUS
16|Nervus muscularis NERVUS MUSCU-|Muscular nerve|General
LARIS
17|Nervus articularis N. ARTHRALIS Arthral nerve |’96 |
18] Plexus nervorum spinal- PLEXUS NERVO-|Plexuses of the|General
ium RUM SPINALIUM spinal nerves
Termini Neurologici Proprii.
I Rhinencephalon Rhinencephalon |Rhinencephal °81
1)Area parolfactoria [Bro-|Area parolfactoria Parolfactory area

cae]
2|Bulbus olfactorius Bulbus olfactorius Olfactory bulb /’81
3\Gyrus subcallosus G. subcallosus Subcallosal gyre
4|Limen insulae Limen Limen :
5|Lobus olfactorius Lobus olfactorius Olfactory lobe |’81
6|Pars anterior (rhinen- ? ?

cephali) ? ?
7\Pars posterior (rhinen- ? ?

cephali)
8|Stria intermedia Radix intermedia Middle root 81
g|Stria medialis Radix mesalis Mesal root SI
1o|Stria olfactoria lateralis|Radix lateralis Lateral root SI
I1|Substantia perforata lat-- PRAECRIBRUM Precribrum 89

eralis
12/\Sulcus parolfactorius ? ?

anterior
13/Sulcus parolfactorius ? fe

posterior
14|Tractus olfactorius Tractus olfactorius Olfactory tract

15|/Trigonum olfactorium |Trigonum olfactorium |Olfactory trigon

WILDER, WVeural Terms.

I Rhinencephalon

“16|[Ventriculus olfacto-/RHINOCOELIA

rius|

Rhinencephalon

17|{[Pars olfactoria foram-/Pars olfactoria aulae

inis interventricu-

laris]

18|[Pars anterior commis-|Pars olfactoria

surae anterioris]

Telencephalon

1|Hemisphaerium

Pallium

Fissura longitudinalis
cerebri

F. transversa cerebri

Gyri cerebri

G, profundi

G, transitivi.

[G. operti]

[G. operientes]
Sulci cerebri
[Fissurae cerebri]
S. et F. operti

S. et F. operientes
Impressio petrosa

Cnt Qt _

Xe)

10
II
12
13
14

commissurae

Prosencephalon

prae-

Rhinencephal

Rhinocele

Olfactory part of
the aula

Olfactory part of)’

the precom-
missure

Prosencephal

Hemicerebrum (cere-
brum /e7e)

Pallium
F. intercerebralis

Hiatus tentorli

GYRI

VADA

ISTHMI

Subgyri

Supergyri
FISSURAE
FISSURAE
Subfissurae
Superfissurae
Impressio petrosa

15|[Impressio confluentis] |Impressio torcularis

16|Fossa cerebri lateralis) FOSSA SYLVII

17|Fissura cerebri lateralis) FISSURA SYLVII

[Sylvii]
[Syl vii]
18} Ramus posterior
19
cendens
20
zontalis
21 [Pars basilaris]

22| Lobi cerebri

23) Insula
24| [Pars anterior]
25 [Pars posterior]
26

sulae]
27 Gyri insulae
28] G. longus insulae
29) Gyri breves insulae

F. SYLVII (fre)

Ramus anterior as-|F, PRAESYLVIANA
Ramus anterior hori-|F. SUBSYLVIANA

F. basisylviana
Lobi cerebri
INSULA

Praeinsula
Postinsula

[Sulcus centralis in-/F, TRANSINSULAR-

IS
G. INSULAE

G. longus insulae

G. breves insulae

Hemicere brum
(cerebrum com-
monly)
Pallium
Intercerebral fis-
sure
Tentorial
val
Gyres or gyri
Vadums
Isthmuses
Subgyres
Supergyres
Fissures
Fissures
Subfissures
Superfissures
Petrosal impres-
sion
Torcular impres-
sion
Sylvian fossa

inter-

Sylvian fissure

Sylvian f. (com-|’

monly)
Presylvian f.

Subsylvian f.
Basisylvian f.
Cerebral lobes
Insula
Preinsula
Postinsula

Transinsular f.

Insular gyres

Long insular

gyre

Short insular

gyres

89
85

General
80, A. G.
INES:
89
89
89

89

304

Telencephalon

Prosencephalon

30|S. circularis [Reili]
31} [Polus insulae]
32)Operculum

33 Pars frontalis
34 Pars parietalis
35 Pars temporalis
36} [Pars orbitalis]

F. circuminsularis
Polus insulae
Opercula
PRAEOPERCULUM
OPERCULUM
POSTOPERCULUM
SUBOPERCULUM

37| S. centralis [Rolandi] |F. CENTRALIS

38] G. centralis anterior

G. PRAECENTRAL-
IS

JOURNAL OF CoMPARATIVE NEUROLOGY.

Prosencephal

382

Circuminsular f.|’89

Insular pole
Operculums
Preoperculum
Operculum
Postoperculum
Suboperculum
Central fissure
Precentral gyre

39| G. centralis posterior |G. POSTCENTRALIS/Postcentral g.

40/[S. centralis inferior]

F. subcentralis

41/[G. transitivus central--ISTHMUS CEN-

s]

TRALIS

Subcentral f,

Central isthmus

i
42|[G. transitivus profun--VADUM CENTRALE)|Central vadum

dus centralis]
43|Lobus frontalis
44| [Pars postfrontalis]
45| [Pars praefrontalis]
46}Polus frontalis
47\Sulcus
[pars superior]
48
inferior]
49|G. frontalis superior

50| S. frontalis superior
51|/G. frontalis medius

Pars superior
Pars inferior

52
53

Lobus frontalis
Pars postfrontalis

Pars praefrontalis

Polus frontalis

praecentralis}F. PRAECENTRAL-

IS

S. praecentralis [pars|F. postfrontalis

G. SUPERFRONT-
ALIS

F. SUPERFRONT-
ALIS

G. MEDIFRONTAL-
IS

Pars dorsalis

Pars ventralis

54/[Sulcus frontalis inter-|F. MEDIFRONTAL-

medius |

55\|Sulcus frontalis inferior

56/G. frontalis inferior

57 Pars opercularis
58 Pars triangularis
59 Pars orbitalis

60)/G. rectus

61|S. olfactorius
62/Gyri orbitales
63|Sulci orbitales
64|Lobus temporalis
65|Polus temporalis

66|Sulci temporales trans-

versi

67|Gyri temporales trans-

versi

68|/G. temporalis superior

69/S. temporalis superior |F. SUPERTEMPOR-|Supertemporal f.

70|G, temporalis medius

IS
F. SUBFRONTALIS
G. SUBFRONTALIS
Pars opercularis
Pars praeopercularis
Pars subopercularis
G. mesorbitalis
F. olfactorius
G. orbitales
F. orbitales
Lobus temporalis
Polus temporalis
F. transtemporales

G, transtemporales

gyres
G. SUPERTEMPOR-|Supertemporal g.

ALIS
ALIS

G.MEDITEMPORAL-|Meditemp’ral g.
IS

Frontal lobe

Postfrontal por-

tion
Prefrontal

tion
Frontal pole
Precentral f.

Postfrontal f.
Superfrontal f.
Superfrontal f.
Medifrontal g.
Dorsal part
Ventral part
Medifrontal f.
Subfrontal f.

Subfrontal g.
Opercular part

Preop’rcular part
Subop’rcul’r part

Mesorbital g.
Olfactory f.
Orbital gyres
Orbital fissures

Temporal lobe
Temporal pole
Transtemporal
fissures
Transtemporal

por-

89; Z102
85
*Si5sWNie
85

85

82, N.2120
85

89

89

89; 2197
89; 2197

General

General
8s
8s
8s
8s
Ss

II
71

IS
72|G. temporalis inferior |G. SUBTEMPORAL-
IS

73
74

75

76

77
78

79
80

81
82
83

84
85
86
87

88
89
go

91
92
93
94

95
96
97
98
99
100
101
102

103
104
105
106
107

WILDER, WVeuval Terms.

Telencephalon

S. temporalis medius

F. collateralis
G. fusiformis

G. lingualis

Lobus occipitalis

Polus occipitalis

S. occipitalis transver-
sus

G.occipitales sup’riores

S. oc. superiores

G. oc. laterales

Lobus parietalis

Lobulus parietalis su-
perior

Lobulus parietalis in-
ferior

Sulcus interparietalis

[Pars postcentralis su-
perior]
[Pars postcentralis in-
ferior]
[Pars horizontalis]
[Pars occipitalis]
[S. praeparoccipitalis]

[S. postparoccipitalis]

[Gyrus transitivus par-
occipitalis]

[G. transitivus opertus
paroccipitalis]

Prosencephalon
F,MEDITEMPORAL-

Prosencephal

Subtemporal g.

F. COLLATERALIS |Collateral f.

G. SUBCOLLATER-|Subcollateral g.
ALIS
G. SUBCALCAR-|Subcalcarine g.

INUS

L. occipitalis

P. occipitalis

F. paroccipitalis
parte)

Occipital lobe

Occipital pole

Part of the par-
occipital f.

(Za

: ?
? ?
> ?

Parietal lobe
Parietal gyre

Lobus parietalis
G. PARIETALIS

G. SUBPARIETALIS|Subparietal g.

Complexus fissuralis in-|Intraparietal fis-
traparietalis (?) sural complex

F, POSTCENTRALIS|Postcentral f.

F, praeparietalis Preparietal f.

F. PARIETALIS Parietal f.

F. PAROCCIPITALIS|Paroccipital f.

F. PRAEPAROCCIP-|Preparoccipital f.
ITALIS

F, POSTPAROCCIPI-|Postparoccipital

Lobulus parietalis in-
ferior
G. supramarginalis
G, angularis
[S. intermedius]
[S. exoccipitalis]
[F. calcarina externa]
5. corporis callosi
S. cinguli
Pars subfrontalis

Pars marginalis
S. subparietalis
F. hippocampi
G. fornicatus

TALIS fissure
ISTHMUS PAROC-/Paroccipital isth-
CIRTTATIS mus
VADUM PAROCCIP-|Paroccipital va-|’
ITALE dum
G. SUBPARIETALIS|Subparietal g.
G. marginalis Marginal gyre
G, angularis Angular g.
F. intermedia (?) Intermedial f.
F. exoccipitalis Exoccipital f.
F. lambdoidalis Lambdoidal f.
F. CALLOSALIS Callosal f.
\[needless]
F. SUPERCALLO- _ _|Supercallosal f.
SALIS

Paracentral f.
Precuneal f,
Hippocampal f.

F. paracentralis
F. praecunealis

F, HIPPOCAMPI
[needless]

395

°82

Meditemporal f.|’85

85

85
85

85

General

General
89

89

85
96
85
86
86
86

"86; 3197

G. cinguli G. CALLOSALIS Callosal g.
1o8|Isthmus gyri fornicati |Isthmus cinguli Isthmus of the|’96
cingulum
Un Uncus

109

I

cus [gyri hippocam-/UNCUS
i]

82

306 JOURNAL OF COMPARATIVE NEUROLOGY.

’

II Telencephalon Prosencephalon Prosencephal 82
I1o|Substantia reticularis |Reticularis alba Reticular alba

‘ alba [Arnoldi]

111/Lobulus paracentralis |G.PARACENTRALIS|Paracentral gyre|‘85
112|Praecuneus PRAECUNEUS Precuneus 785 Gane
113|F. parietooccipitalis |F. OCCIPITALIS Occipital fissure |’85
114\F. calcarina F, CALCARINA Calcarine f. 85 G. N.
I15|F. occipito-calcarina |F, occalcarina Occalearine f. |'89
116)[S. postcalcarina] F. postcalcarina Postcalcarine f. |’85
117|Cuneus CUNEUS Cuneus 89 G. N.
118|[Isthmus cunei] ISTHMUS CUNEI |Cuneal isthmus |’96
119|[Isthmus opertus cunei]| Vadum cunei Cuneal vadum_ |'96
120/[S. adoccipitalis] F. adoccipitalis Adoccipital f. — |’89
121|[Cuneus anterior] CUNEOLUS Cuneolus 95
122|[S. inflecta] F. inflecta Inflected f. 85
123|[S. fronto-marginalis] |F. fronto-marginalis Fronto-marginal |’89

124|S. oc. laterales ? ?

il. B. Cava et Corum Parietes.

II Telencephalon Prosencephalon Prosencephal | 82
1\[Cavitas telencephali] |PROSOCOELIA Prosocele 86; 2201
2\[Pars medialis foramin-|AULA (ere) Aula(commonly)|’80; 4211

is interventricularis]
3)[Pars lateralis foraminis| PORTA Porta "81; 2211
interventricularis]
4/Ventriculus lateralis PARACOELIA Paracele ’S9
5 Pars centralis CELLA Cella 82
6} Cornu anterius PRAECORNU Precornu 81; 7185
7 Cornu posterius POSTCORNU Postcornu SI
8] Cornu inferius MEDICORNU Medicornu "81
9|Corpus striatum STRIATUM Striatum 80; N.
10/Nucleus caudatus CAUDATUM Caudatum 80; Q11I
It Caput nuclei caudati/CAPUT Caput ‘89; 726
12 Cauda nuclei caudati/CAUDA Cauda iste)
13/Stria terminalis Taenia Tenia 89
14|Lamina affixa ? ?
15|Taenia chorioidea RIPA Ripa 82a
16|Lamina chorioidea epi-- PARATELA Paratela *89
thelialis
17|Calcar avis CALCAR Calcar (7106) ’81;A.N.S.
18/(Bulbus cornu poste--EMINENTIA OCCIP- Occipital emi -|’89
rioris) ITALIS nence
19|Eminentia collateralis |EMINENTIA COL- [Collateral emi-|/General
LATERALIS nence
20/Trigonum collaterale |Trigonum collaterale |Collateral trigon|’96
21|/Hippocampus HIPPOCAMPUS Hippocamp 780), AC Gre
N.S
22|Fimbria hippocampi |FIMBRIA Fimbria 81
23/Taenia fimbriae RIPA Ripa SI
24/Digitationes hippo-|Digitationes hip po-|Hippocampalj’96
campi campi digitations
25|Fascia dentata hippo-|Fasciola Fasciola SI

campi

Wiper, Neural Terms.

Il

6|Fasciculus longitudina-
lis inferior
7\Fasciculus longitudina-
lis superior
8}Fasciculus uncinatus
g|Radiatio corporis cal-
losi

Fasciculus dorsalis
Fasciculus ventralis

Fasciculus uncinatus

Radiatio callosi

Telencephaloa Prosencephalon Prosencephal | ’82
26/Commissura hippo- |Fornicommissura Fornicommis- |’89
campi sure
27|Corpus callosum CALLOSUM Callosum (Z111) 80 N.
28} Splenium corporis |SPLENIUM Splenium 80
callosi
29} Truncus corporis |CALLOSUM (fere) Callosum (com-|’80
callosi j monly)
30| Genu corporis cal-\GENU '/Genu 81; 226
losi
31 Rostrum corporis |ROSTRUM Rostrum SI
callosi
32 Lamina rostralis Copula Copula ‘ 89
8 Striae transversae |Striae transversae Transverse striae|’98
34 Stria longitudinalis|Stria mesalis Mesal stria 96
medialis i
35) Stria longitudinalis|Stria lateralis Lateral stria 96
lateralis ;
36 Fasciola cinerea Fasciola Fasciola 81
37| [Indusium] Indusium Indusium 93
38) Fornix FORNIX Fornix General
39 Crus fornicis needless ; ;
40 Corpus fornicis FORNIX (fre) Fornix (com-|’80
monly)
41 Taenia fornicis Ripa Ripa.
2 Columna fornicis Fornicolumna Fornicolumn 84
43| Pars libera colum-|Pars libera fornicolum-|Free part of the)’96
nae fornicis nae fornicolumn
44! Pars tecta columnae|Pars tecta fornicolum- Concealed part ’96
fornicis nae of the forni-
column
45| [Crista] CRISTA Crista ’80; Z210
46) [Carina] CARINA Carina 81
47\Septum pellucidum |SEPTUM Septum 89; 726
48 Lamina septi pellu-- HEMISEPTUM Hemiseptum 82
cidi
49| [Cavum septi pellu-/PSEUDOCOELIA Pseudocele SI
cidi|
Ii. €. Sectiones Prosencephali.

I Telencephalon Prosencephalon Prosencephal 782
1\Substantia corticalis |CORTEX Cortex SI
2|Centrum semiovale MEDULLA Medulla "89; 726
3|Decursus fibrarum cer-

ebralium ?
4|Fibrae arcuatae cerebri ?
5/Cingulum Cingulum Cingulum

Dorsal fasciculus

Ventral fascicu-
lus

Uncinate
culus

Callosal rad ia-
tion

fasci-

307

308 JoURNAL OF COMPARATIVE NEUROLOGY.
II Telencephalon Prosencephal Prosencephal 81
Io} Pars frontalis Radiatio frontalis Frontal radia-
tion
11| Pars parietalis Radiatio parietalis Parietal radia-
tion
12| Pars temporalis Radiatio temporalis Temporal radia-
tion
13] Pars occipitalis Radiatio occipitalis Occipital radia-
tion
14) Tapetum Tapetum Tapetum General
15|Nucleus lentiformis LENTICULA Lenticula 89; 19
16| Putamen PUTAMEN Putamen General
17| Globus pallidus Pallidum Pallidum 96
18|Claustrum CLAUSTRUM Claustrum General
19/Capsula externa ig ?
20|Capsula interna Capsula Capsula 89
21; Genu capsulae inter-/Genu Genu
nae
22| Pars frontalis capsu-|Pars frontalis Frontal part
lae internae
23| Pars occipitalis c. i. -|Pars occipitalis Occipital part
24|Nucleus amygdalae Amygdala Amygdala 85
25|Corona radiata CORONA Corona 89
26| Pars frontalis Pars frontalis Frontal part
27| Pars parietalis ijPars parietalis Parietal part
28} Pars temporalis Pars temporalis Temporal part
29| Pars occipitalis Pars occipitalis Occipital part
30|Radiatio corporis striata|Radiatio striatalis Striatal radia-
tion
31|Radiatio occipitothal- |Radiatio thalamica Thalamic radia-
amica [Gratioleti] tion
32|Commissura anterior |PRAECOMMISSURA| Precommissure |’81
[cerebri]
33| Pars anterior (see I, 18)
34| Pars posterior Pars temporalis Temporal portion
ne ° -
iil Whale odceohalon Diencephalon Diencephal Sl
1|Thalamus THALAMUS Thalamus 80, G. N.
2} Pulvinar PULVINAR Pulvinar General
3} Tuberculum anterius|/Tuberculum thalami |Thalamic_tuber-
thalami cle

4| Taenia thalami RIPA Ripa 81; 3240

5| Stria medullaris Stria medullaris Meduilary stria

6| Lamina chorioidea {Pars marginalis dia-|Marginal part of
epithelialis telae? diatela (needless)

7|Metathalamus (Neediess)

8| Corpus geniculatum]POSTGENICULUM |Postgeniculum |’89
mediale

9} Corpus geniculatum]/PRAEGENICULUM |Pregeniculum |’89
laterale

10| Epithalamus (Needless) 96

11| Corpus pineale EPIPHYSIS Epiphysis 95; 768

12| Recessus pinealis Recessus epiphysialis |Epiphysialrecess

13} Recessus suprapine-|Saccus dorsalis Dorsal sack 96, d

alis

Wiper, Neural Terms. 309

Ill PREG EAEeEH AION Diencephalon Dience phal 81

14 Habenula HABENA Habena SI

15} Commissura habenu-/SUPRACOMMISSU- Supracommis-_ |’86

larum RA (H. F. Osborn) sure

16| Trigonum habenulae|Trigonum habenae Habenal trigon |’96

17| Hypothalamus : (Needless)

18|Pars mamillaris hypo- (Needless)

thalami

19} Corpus mamillare ALBICANS Albicans 81
20|Pars optica hypothalami (Needless)

21| Tuber cinereum Tuber Tuber 9

22| Infundibulum INFUNDIBULUM Infundibulum /’S1, G.N.
23| Hypophysis HYPOPHYSIS Hypophysis 80, G.N.
24 Lobus anterior Praehypophysis Prehypophysis |’89

25 Lobus posterior Posthypophysis Posthypophysis |’89

26| Tractus opticus TRACTUS OPTICUS |Optic tract General
27 Radix medialis Radix mesalis Mesal root SI

28 Radix lateralis Radix lateralis Lateral root ‘$1
29|Chiasma opticum CHIASMA Chiasma 80, N.
30|Lamina terminalis TERMA Terma SI

Ili. B. Cavitas Diencephali

ll Diencephaion et

Thalamencephalon Diencephalon Diencephal S81
1}Ventriculus tertius DIACOELIA Diacele "SI
2|Aditus ad aquaeduc- (Needless)

tum cerebri
3/Commissura posterior |POSTCOMMISSURA |Postcommissure |’81
[cerebri]
4|Foramen interventricu-|(Vide Prosencephalon |(See Prosenceph-
lare [Monroi]| B, 2) al B, 2)
5\Sulcus hypothalamicus) Aulix Aulix (2195) 84
[Monroi]
6| Massa intermedia ~ |MEDICOMMISSURA | Medicommissure|’80
7\Recessus opticus RECESSUS OPTICUS]|Optic recess 82
8}Recessus infundibuli |RECESSUS INFUN-|Infundibular re-
DIBULI cess
9|Commissura anterior |(Vide Prosencephalon |(See Prosenceph-
[cerebri] C, 32) aly@ 32)
10|Recessus triangularis |Recessus aulae Aulic recess (See|’81

Prosen, B, 2;
’ 2240

310 JoURNAL OF ComPARATIVE NEUROLOGY.
Hil. C. Sectiones Diencephali
Jiencephaton et . :
Til oN ee aan DPiencephalon Diencephal 81
I1/Stratum zonale
12)Nucleus anterior thal-
ami
13|N. medialis thalami
14|N. lateralis thalami
15!Laminae medullares
thalami
16} Nucleus corporis genic-
culati medialis
17|N. c. g. lateralis
18|N habenulae Nidus habenae Habenal nidus
I9|Fasciculus retroflexus |Fasciculus retroflexus |Fasciculus retro-
[Meynerti] flexus i
20|Nucleus hypothalami-
cus [Corpus Luysi]
21/Pars grisea hypothala-
mi
22|Commissura superior
[Meynerti]
23|Commissura inferior| Infracommissura Infracommissure
[Guddeni]
24|Nuclei corporis mamil-|Nidi albicantiae Albicantial nidi
laris
25|Fasciculus thalamoma-
millaris [Vicq qd’
Azyri]
26|Fasciculi pedunculo-
mamillaris
27| Pars tegmentalis
28} Pars basilaris
29|Ansa peduncularis
30| Pedunculus thalami
inferior
31} Ansa lenticularis
IV| Mesencephalon Mesencephalon Mesencephal |’8S1,Gen’l
1;Aquaeductus cerebri |MESOCOELIA Mesocele SI
[Sylvii]
2|Basis pedunculi CRUSTA Crusta 89
3\Brachium quadrigemi-|/POSTBRACHIUM Postbrachium — |’89
num inferius
4\Brachium quadrigem-;/PRAEBRACHIUM _ |Prebrachium 89
inum superius
5/Colliculus interior POSTGEMINUM Postgeminum |’89
6!Colliculus superior PRAEGEMINUM Pregeminum 89
7\Corpora quadrigemina |QUADRIGEMINUM (|Quadrigeminum |'89
8|Decussatio brachii con-|Decussatio brachii Brachial decus-
junctivi sation
9|Decussationes tegmen-|Decussationes tegmen-|Tegmental de-
torum torum cussations
1o|Fasciculus longitudina-|Fasciculus longitudina-|Longitudinal
lis medialis lis | fasciculus

Wiper, Neural Terns.

31g

lV Mesencephaton Meseneephalon Meseneephal |°81,Gen‘l
11|Formatio reticularis |Reticula Reticula
12|Fossa interpeduncularis FOSSA INTERCRU-|Intercrural fossa)’89
[Tarini] RALIS

13| Lamina quadrigemina

14;Lemniscus lateralis

15|Lemniscus medialis

16|Nucleus colliculi in-
ferioris

17|Nucleus nervi oculomo-
torll

18| Nucleus radicis descen-

dentis n. trigemini
19}Nucleus ruber
20| Nuclei tegmenti
21|Pedunculus cerebri

22|Radix descendens n.
trigemini
23|Recessus anterior
[of 12]
24|Recessus posterior
25/Stratum album profun-
dum
26|Stratum griseum cen-
trale

Stratum griseum collic-
ull superioris

Stratum zonale

Substantia nigra

Substantia periorata
posterior

27

Lemniscus lateralis

Lemniscus mesalis

|
(

Nidus oculomotorius

| RUBRUM

Nidi tegmenti

CRUS

Recessus postcribralis

Recessus praepontilis

Entocinerea

CAPPA

INTERCALATUM
POSTCRIBRUM

31/Sulcus lateralis Sulcus lateralis
32|Sulcus n. oculomotorii |Sulcus oculomotorius
33) Tegmentum, TEGMENTUM
34|[Tractus pedunculi “IMBIA
transversus |
35|Velum medullare ant. |)VALVULA
36|Frenuium veli med. ant |FRENULUM
Vv Metenvephalon Epencephalon
1/[Pars metencephalica |\picoetia
ventriculi quarti]
2|[Pars metencephalica |Praeoblongata
medullae oblongatae]
3)Cerebellum CEREBELLUM
4\Sulci cerebelli Sulci et rimulae
5|Gyri cerebelli FOLIA
6} Vallecula cerebelli VALLIS
7\Incisura cerebelli pos-
terior

|

Lateral lemnis-|’89, G. N.

cus
Mesal lemniscus

Oculomotor ni-

dus

Rubrum
Tegmental nidi
Crus (2196)

Postcribral re- |
cess

Prepontile recess

Entocinerea 89
Cappa "89
Intercalatum 80; 2241.
Posteribrum 89
Lateral sulcus |’89
Oculomotor sul-|’89

cus
Tegmentum 89, G.N.
Cimbia 81
Valvula 81
Frenulum 89; 2241

Epencephal St
Epicele Sr
Preoblongata 85
Cerebellum General
(Sues andrimulas|'89; 3241
Foliums *S9
Vallis 906

312

¥ Metencephaton
8/Sulcus horizontalis
cerebelli

go] Fissura transversa cere-

belli

Io] Vermis

11|Lingula cerebelli

12|Vincula lingulae cere-

belli

13|Lobus centralis

14|Monticulus

15/Culmen

16|Declive

17|Folium vermis
18] Tuber vermis
19|Pyramis [vermis]
20|Uvula [vermis]
21|Nodulus
22| Hemisphaerium
belli
23|[Sulcus praeclivalis
24|Ala lobuli centralis
25|Lobulus quadrangularis

cere-

26) Pars anterior

27| Pars posterior

28|Lobulus semilunaris su-
perior

29! Lobulus semilunaris
inferior

3c| Lobulus biventer

31{[Lobulus gracilis]

32|Flocculus

33|Flocculi secundarii
34 ee oe

ce ce

36|Pedunculus flocculi

37|Nidus avis

38|[Folium cacuminis]
>

4o0|Brachium conjuncti-
vum cerebelli

41|[Fossa praepeduncu-
laris|

42| Fastigium

43| Pons [Varoli]

44| Sulcus basilaris

45| Fasciculus obliquus
pontis

46| Fila lateralia pontis

47| Brachium pontis

.

Epencephalon

JOURNAL OF COMPARATIVE NEUROLOGY.

Epencephal

Sulcus peduncularis

is

VERMIS
LINGULA
Folia

MONTICULUS
CULMEN
DECLIVE

Tuber

Pyramis

UVULA

NODULUS

Pileum (B. B. Stroud)

Sulcus furcalis
Lobus quadrangularis

Pars cephalica
Pars caudalis
Lobus praesemilunaris

Lobus postsemilunaris

Lobus cuneiformis
Lobus gracilis
FLOCCULUS
Paraflocculus
Supraflocculus
Mediflocculus
>

?
Cacumen

POSTPEDUNCULUS
PRAEPEDUNCULUS

Fossa praepeduncularis

FASTIGIUM
PONS

SULCUS BASILARIS
Fasciculus obliquus

?
MEDIPEDUNCULUS

81

Peduncular sul-|’89

cus
?

Vermis
Lingula
Foliums 7241

Monticulus
Cuimen
Declive

Tuber
Pyramid
Uvula
Nodulus
Pileum; 3241

Furcal sulcus

Quadrangular
lobe
Cephalic part
Caudal part
Presemilunar
lobe
Postsemilunar
lobe
Cuneiform lobe
Slender lobe
Flocculus
Paraflocculus
Supraflocculus
Mediflocculus

2241
Cacumen
Postpeduncle
Prepeduncle

Prepeduncular

fossa
Fastigium
Pons

Basilar sulcus
Oblique fascicle

Medipeduncle

89

89
89
89
94
"904
"94

89
82
7825-2241

"89

89
80, A.
G. N.S.

81; 7198

WILpvER, Neural Terms.

Y. B. Sectiones Pontis et Cerebelli.

Metencephalon Epencephalon

Epencephal

——— | _ eee Oe

I
2

3

Pars dorsalis pontis
Raphe Rhaphe
Nucleus n. abducentis |Nidus abducentis

4|Nuclei motorii n. trig-

5

6

7

8
9

10
II
12
13
14
15
16

17

21|Lemniscus LEMNISCUS
22| L. medialis sensitivus
23| Lz. lateralis acusticus
24|Pars basilaris pontis
25|Fibrae pontis profundae|Fibrae pontis entales
26|Fasciculi longitudinales

[pyramidales]
27|Nuclei pontis Nidi pontis
28|Fibrae pontis superfic- |Fibrae pontis ectales

jalis

29/Corpus medullare Medulla
30; Laminae medullares Laminae medullares
31|/Arbor vitae ARBOR
32| [Ramus posterior] Postramus
33) [Ramus anterior] Praeramus
34|Substantia corticalis CORTEX
35| [Lamina basalis] [35, 30 and 37 are
36) [Stratum cinereum] bracketed in the Ger-
37| [Stratum gangliosum]} man list]
38| Stratum granulosum
39|Nucleus dentatus DENTATUM (6123)
40| Nucleus fastigii Fastigatum
41|Nucleus emboliformis |Embolus

emini
Radix descendens [mes-
encephalica] n. trig-
emini
Tractus spinalis n.
trigemini
Nucleus tractus spinalis
n. trigemini
Nucleus n. facialis Nidus facialis
Radix n. facialis Radix n. facialis

Pars prima
Genu [internum]

Pars secunda
Nuclei n. acustici Nidi acustici
Nuclei n. cochlearis |Nidi n. cochlearis
Nuclei n. vestibularis| Nidi n. vestibularis
Nucleus olivaris supe-
rior
Nucleus lemnisci later-
alis
Fasciculus longitudi- |Fasciculus longitudi-
nalis medialis nalis
Formatio reticularis
Corpus trapezoideum |TRAPEZIUM

42|Nucleus globuliformis |Globulus

Rhaphe
Abducent nidus

Facial nidus
Root of the fac-
ial nerve

Acoustic nidi
Cochlear nidi
Vestibular nidi

Longitudinal fas-
ciculus

Trapezium
Lemniscus

Ental fibers of
the pons

Pontile nidi
Ectal fibers of
the pons
Medulla
Medullary lami-
nae
Arbor
Postramus
Preramus
Cortex

Dentatum
Fastigatum
Embolus
Globulus

"81; 219
89, G.N

314 JouRNAL OF CoMPARATIVE NEUROLOGY.

VI| Myelencephaion Metencephalon Metencephal °80
1}Ventriculus quartus |Metepicoelia Metepicele ’86; 7242

[cavitas communis
myelencephali et
metencephali]
2|Fossa rhomboidea
3|Pars inferior fossae Calamus Calamus "82
rhomboideae [cala-
mus scriptorius]
4|Pars intermedia f. r.
5|Pars superior f. r.
6\Sulcus limitans f. r. —_ |Sulcus interzonalis (?) |Interzonal sulcus
7| Fovea inferior 2195
8| Fovea superior
9|/Trigonum n. hypoglossi |

10|Striae medullares Striae acusticae Acoustic striae
11|Eminentia medialis
12|Colliculus facialis Lophius facialis Facial lophius
13|Ala cinerea Ala cinerea
14|Area acustica Area acustica
15|Locus caeruleus Locus caeruleus
16|[Hordea] Hordea [Spitzka] Hordeums
17|Tegmen ventriculi
quarti
18/Velum medullare pos- |Kilos Kilos
terius 9242
19) Taenia ventriculi quarti|Ligula Ligula 89; 7239
20|Obex OBEX Obex 89; 7242
21)Lamina chorioidea epi-|Pars marginalis meta- |(Needless)
thelialis telae
22|(Apertura medialis ven-| METAPORUS Metapore 89; '93, «

triculi quarti [Fora-
men Magendii] )

23)(Apertura lateralis ven- (Existence “OGG
triculi quarti) doubted)

24|Fastigium (See V, 42)

25|Medulla oblongata Postoblongata Postoblongata |’85

26|[Pars myelencephalica |METACOELIA Metacele SI

ventriculi quarti] :
27|Fissura mediana poster-[SULCUS DORSALIS |Dorsal sulcus [2132

jor
28|F. mediana anterior S. VENTRALIS Ventral sulcus
29|Foramen caecum Recessus postpontilis |Postpontile re- |'81
cess
30|Pyramis [medullae ob- |PYRAMIS Pyramid "81
longatae]
31|Decussatio pyramidum |Decussatio pyramidum| Pyramidal decus |General
sation
32|Sulcus lateralis anterior|Sulcus ventrolateralis |Ventrolateral
sulcus
33|S. lateralis posterior |S. dorsolateralis Dorsolateral
sulcus
34|Oliva OLIVA Oliva 86, G. N.
35|Corpus restiforme RESTIS Restis 89; 219
36|Funiculus lateralis Funiculus lateralis Lateral funiculus
37|Funiculus cuneatus Funiculus cuneatus Cuneate funi-

culus

WILDER, Neural Terms. 315

VI| Myelencephalon Metencephalon Metencephal 280
38/Tuberculum cinereum |Tuberculum cinereum /Cinereal tubercle
39|Funiculus gracilis Funiculus gracilis Slender funiculus
40|Clava CLAVA Clava 81, G.N.
41|Fibrae arcuatae exter- |Fibrae arcuatae ectales|Ectal arched fi-

nae bers

VI. B. Sectiones Postoblongatae.

VI| Myelencephalon Metencephalon Metencephal 80
ING Raphe Rhaphe Rhaphe (3242)

2|/Stratum nucleare Stratum nidale Nidal stratum
3\Nucleus n. hypoglossi |Nidus hypoglossi Hypoglossal ni-
dus
4|Nucleus ambiguus
5|Nucleus alae cinereae
6|Tractus solitarius
7\Nucleus tracti solitaril
8|Tractus spinalis n. tri-
gemini
g|Nucleus tractus spinalis
n. trigemini
10|Nucleus funiculi grac-
ilis
11/Nucleus funiculi cu-
neati
12| Nuclei laterales
13}Nucleus olivaris infe-
rior
14|Nucleus olivaris acces-
sorius medialis
15|Nucleus olivaris acces-
sorius dorsalis
16] Nuclei arcuati !
17|Fibrae arcuatae inter- |Fibrae arcuatae entales|Ental arched fi-
nae bers
18|Substantia reticularis
grisea
19|Substantia reticularis
alba
20|/Fasiculus longitudi- |Fasciculus longitudi- |Longitudinal
nalis medialis nalis fasciculus
21\Stratum interolivare
lemnisci
22|Decussatio lemniscor-
um
23|Corpus restiforme RESTIS Restis 89; 319
24|Fasciculi corporis rest-
iformis
25|Fibrae cerebellodlivares
26| Fasiculi pyramidales
27|Fibrae arcuatae exter- |Fibrae arcuatae ectales|Ectal arched fi-
nae bers

NT WW

316 JOURNAL OF GOMPARATIVE NEUROLOGY.

VII} Medulla spinalis Myelon Myel °S1; 251
~~ }Pars cervicalis Myelon cervicale Cervical myel
2|Intumescentiacervicalis|Intumescentia cervi- |Cervical enlarge-
calis ment
3}Pars thoracalis Myelon thoracale Thoracic myel
4|Pars lumbalis Myelon lumbale Lumbar myel
5|Intumescentia lumbalis|Intumescentia lumbalis| Lumbar enlarge-
ment
6}Conus medullaris CONUS Conus
7|Filum terminale FILUM Filum

8|Ventriculus terminalis |RHOMBOCOELIA /Rhombocele 85
9|Fissura mediana anter- [SULCUS VENTRAL-|Ventral sulcus

ior Is
1o/Sulcus medianus poster-SULCUS DORSALIS |Dorsal sulcus {#132
ior
11/Sulcus lateralis anterior/Sulcus ventrolateralis |Ventrolateral
sulcus
12/Sulcus lateralis poster- [Sulcus dorsolateralis | Dorsolateral sul-
ior cus
13/Sulcus intermedius an- |Sulcus intermedius ven-| Intermediate
terior tralis ventral sulcus
14|Funiculi medullae spin-|Columnae szve funes s, |Myelic columns |’81; 2130
alis funiculi myeli or funes or funi-
culi
15 Funiculus anterior |Columna ventralis Ventral column (#132
16} Funiculus lateralis |Columna lateralis Lateral column
17| Funiculus posterior |Columna dorsalis Dorsal column

Vil. B. Sectiones Myeli.

VII| Medulla spinalis Myelon Myel °S1; 251
1|Canalis centralis MYELOCOELIA Myelocele 85
2|Substantia grisea cen- |ENTOCINEREA Entocinerea 89

tralis
3|Commissura anterior |Commissura ventralis |White ventral
alba alba commissure ;
4|Commissura anterior |Commissura ventralis |Gray ventral
grisea cinerea commissure
5|Commissura posterior |Commissura dorsalis |Dorsal commis-
sure
6|Columnae griseae Cornua cinerea sive {Gray cornua or |’§1; 3128
columnae cinereae columns
Columna anterior Cornu ventrale Ventral cornu [131
g|Columna lateralis Cornu laterale Lateral cornu
Columna posterior Cornu dorsale Dorsal cornu
1o| Cervix columnae pos-
terioris

11, Apex col. post.
12| Substantia gelatinosa
[Rolandi]
13| Nucleus dorsalis [Stil-
lingi, Clarkii]
14|Formatio reticularis Reticula Reticula
15|Funiculus anterior Columna ventralis Ventral column |7130

Vil

Wiper, Neural Terms. S17

16

Medulla spinalis Myelon Myel 815 251

Fasciculus cerebro-
spinalis anterior
[pyramidalis ante-
rior]

17| Fasciculus anterior
proprius [Flech-
sigi|
18|Funiculus lateralis Columna lateralis Lateral column |?130
19| Fasciculus cerebro-
spinalis lateralis
[pyramidalis later-
alis]
20| Fasciculus cerebello-
spinalis
21) Fasciculus anterolat-
eralis superficialis
[Gowersi]
22| Fasciculus lateralis
proprius [Flech-
sigi]
23|Funiculus posterior Columna dorsalis Dorsal column |?130
24| Fasciculus gracilis
[Golli]
25| Fasciculus cuneatus
[ Burdachi ]
Vill Meninges
1|Dura mater encephali }|DURA Dura (2116) 80: N.
2|Falx cerebri FALX Falx (2124) Sq: N.
3|Tentorium cerebelli TENTORIUM Tentorium N.
4|Falx cerebelli FALCULA Falcula
5|Diaphragma sellae
6| Foramen diaphragmatis
sellae
7|Incisura tentorili Incisura tentoril Tentorial incis-
ion
8|Dura mater spinalis Dura spinalis Spinal dura
9|Filum durae matris spi-|Filum durae Dural filum
nalis
Io/Cavum epidurale Cavum epidurale Epidural cavity |118
11\Cavum subdurale Cavum subdurale Subdural cavity
12)Arachnoidea encephali |ARACHNOIDEA Arachnoid 80; 2118
13|Cavum subarachnoidale|Cavum subarachnoidale|Subara chnoid
cavity
14|Cisternae subarachnoid-|Cisternae Cisterns
ealae
15|Cisterna cerebello-med-|Postcisterna s. c. cere- |Postcisterna or |’89
ullaris bellaris cerebellar cis-
tern
16|Cisterna fossae lateralis} Cisterna Sylviana Sylvian cistern
cerebri (Sylvii)
17|Cisterna chiasmatis Cisterna chiasmatis Chiasmatic cis-
tern
18|Cisterna interpeduncu- |Cisterna cruralis Crural cistern 2196

laris

318 JOURNAL OF COMPARATIVE NEUROLOGY.

VII Meninges

19/Cisterna venae magnae |Medicisterna Medicisterna 89
cerebri

20/Granulationes arach-
noideales [Pacchi-

oni]

21|[Leptomeninges] Piarachnoidea Piarachnoid 89

22|Pia mater spinalis Pia spinalis Spinal pia

23|Ligamentum denticula-|_Ligamentum denticula-|Denticulated lig-
tum tum ament

24|Septum cervicale inter-
medium

25|Pia mater encephali PIA Pia (2117) 80; N.

26|Tela chorioidea ventric-|-METATELA Metatela SI
uli quarti

27|Plexus chorioideus ven-- METAPLEXUS Metaplexus SI
triculi quarti

28/Tela chorioidea ventric: DIATELA Diatela Table IV
uli tertii

29| Plexus chorioideus ven- Diaplexus Diaplexus
triculi tertii

30| Plexus chorioideus ven- PARAPLEXUS Paraplexus 89
triculi lateralis

31)/Glomus chorioideum Glomus Glomus

32) Acervulus Acervus Acervus

33|[Plexus chorioideus tel-|/ PROSOPLEXUS Prosoplexus
encephali]

34|[Tela foraminis inter- ;|AULATELA Aulatela
ventricularis]

35|[Plexus chorioideus for-| f AULIPLEXUS Auliplexus "SI
aminis interventri-| | PORTIPLEXUS Portiplexus
cularis]

36|[Lamina chorioidea epi--PARATELA Paratela 89

thelialis (II, 16)]

IX. Principal Entocranial Bloodvessels; 7242

A, Intrinsic Encephalic Arteries.

1|Basilaris BASILARIS Basilar General
2\Cerebelli inferior ante- |MEDICEREBEL- Medicerebellar |’85
rior LARIS
3\Cerebelli inferior pos- Beata aoe Postcerebellar |’85
terior S)
4|Cerebelli superior PRAECEREBEL- Precerebellar 9147
LARIS
5|Cerebri anterior PRAECEREBRALIS |Precerebral 85
6;Cerebri media MEDICEREBRALIS |Medicerebral 85
7\Cerebri posterior POSTCEREBRALIS |Postcerebral 85
8|Cerebri anterior media |TERMATICA Termatic 85
g|Circulus arteriosus[ Wil-|Circulus Circulus
lisi
10 2) anterior |[PRAECOMMUNI- Precommuni- 85
CANS cant
11|\Communicans posterior) POSTCOMMUNI- Postcommuni- _ |’85

CANS cant

Witpver, Neural Terms. 319
A. Intrinsic Encephalic Arteries.
12|Chorioidea anterior PRAECHOR OIDEA | Prechoroid 85,
13|Chorioidea POSTCHOROIDEA | |Postchoroid "85
14|Perforantes anteriores |PRAECRIBRALES |Precribral 85
15|Perforantes posteriores |POSTCRIBRALES Postcribral 85
16\Spinalis anterior SPINALIS VEN- Ventral spinal
TRALIS
17|Spinalis posterior SPINALIS DORSAL-|Dorsal spinal
Is
18)Ramus meningeus Ramus meningeus Meningeal ramus
19| Vertebralis VERTEBRALIS Vertebral General
20/Rami spinales Rami spinales Spinal rami
B. Dural Arteries.
1} Meningea anterior PRAEDURALIS Predural 89
2|Meningea posterior POSTDURALIS Postdural |
3|Meningea media MEDIDURALIS Medidural
4|Meningea parva Parviduralis Parvidural
5|Meningea inferior Subduralis Subdural
C. Sinuses.
1|Transversus \Lateralis ' Lateral
2|Sagittalis superior Longitudinalis Longitudinal
3|Sagittalis inferior FALCIALIS Falcial
4|Rectus TENTORII Tentorial
5|Petrosus inferior Subpetrosus Subpetrosal
6|Petrosus superior Superpetrosus Superpetrosal
7|\Sphenoparietalis Sphenoparietalis Sphenoparietal
8)Confluens sinuum Torcular Torcular
D. Encephalic Veins.
1\Cerebri superiores Supercerebrales Supercerebral |’89
2|Cerebri media Medicerebralis Medicerebral
3\Cerebri inferiores Subcerebrales Subcerebral
4|Cerebelli superiores Supercerebellares Supercerebellar
5|Cerebelli inferiores Subcerebellares Subcerebellar
6|Cerebri internae Velares Velar
7|Cerebri magna [Galeni]|Magna (?)
8|Septi pellucidi Septalis Septal
g|Terminalis
Io) Basalis [Rosenthali] Basalis
11|Chorioidea Choroidea Choroid

12}Opthalmomeningea

?

Notr.—To save space the substantive

(arteria, vena, stnus) are omitted.

elements of the vasal dionyms

320 JOURNAL OF COMPARATIVE NEUROLOGY. |

Comments upon Table VI.

$239. Generval.—Professor Kolliker has characterized (’96,
814; §208) ‘‘the anatomic nomenclature coming from America
in recent years as a complete failure.’’ Professor His has declared
(95, 6, 7; §170) that the writer’s ‘‘ proposals tend to create
a language entirely new and for the most part quite strange,
and on this ground our commission cannot follow him without

») “AS a main basis of this

renouncing its historic principles.
conclusion, he imputes to me either (according to the intended
sense of ‘verlangen lauter Mononyme’’) a strong desire for
mononyms, or a demand for them to the exclusion of all polyo-
nyms. Since the foregoing extracts might well indicate the
existence of a divergence, wide, radical and irreconcilable, be-
tween the neural terminology preferred by me and that recom-
mended by the Gesellschaft, attention is asked to the following
statistics :

(2) Among the (about) 540 terms on the German list
there are about 100 concerning which I refrain from expressing
an opinion; my doubts are indicated sometimes by blanks in
the second column, and sometimes by interrogation points.

(6) Among the (say) 440 remaining, the following are so
commonly employed that I claim no especial credit for having
adopted many of themso long ago as 1880 or 1881 :—Nervus,
ganglion, ramus communicans, ramus anastomoticus, nervus cutan-
eus, nervus muscularis, plexus nervorum spinalium, lobt cervebri
(frontalis, parietals, occipitalis et temporalis), eminentia collater-
alis, fornix, tapetum, putamen, claustrum, pulvinar, tractus opticus,
mesencephalon, cerebellum, decussatio pyramidum.

(c) Among the (say) 420 remaining, respecting at least 105
(about one-fourth) there is complete, or practically complete,
concordance between the German committee and myself; of
these, several were adopted between 1880 and 1882, and nearly
all prior to the report of the German committee.

1 Ts it permissible to entertain the hypothesis that not the least operative of
these deterrent ‘‘historic principles’? are an indifference to what is done in
America, and an indisposition to recognize value therein ?

WILpER, Weural Terms. 321

(2) Among the remainder (say 315), about 25, viz., prae-
cribrum, postcribrum, vadum, aula, porta, vipa, copula, crista,
carina, terma, cimbia, folium, pileum, metaporus and the com-
pounds of coelza, may be regarded as unfamiliar.

(c) But with most of the others the differences from the
German equivalents may be indicated by the following exam-
ples :—Calcar (for calcar avis), callosum (for corpus callosum),
dura (for dura mater), postcornu (for cornu posterius), praecom-
missura (for commiéssura anterior), gyrus subfrontalis (for gyrus
frontalis inferior), medipedunculus (for drachium pontis), habena
(for habenula), trapezium (for corpus trapezoides), radix dorsalis
(for radix posterior), diaplexus (for plexus choriowdeus ventricult
tertiz) ; see Part IV.

(f) Finally, the German list contains at least forty mono-
nyms, while in my own list of about 440, at least 270, more
than one half, are polyonyms; see $242, IX.

S240. Special.in the division ‘‘Termini Neurologici
Generales’, in the sixth line, the term TZaenza telarum of the
German list is made equivalent to my Ripa. A similar equiva-
lency is indicated in II, B, 15 and 23; andin III, 4. In re-
spect to these, and also the interpretations implied in II, B, 13;
III, 5; and VI, 19, I wish to make further observations. I was
early (81, @) impressed with the morphologic significance of
these marginal parts or ‘‘shore-lines’”’ of the encephalic cavities,
but now that the foregoing list is printed I am disposed to think
that in my recent revision sufficient attention was not paid to
the diagrams and suggestions of Prof. His (95, 165-168). If
his views prove to be correct I shall be pleased, since upon
some other points I have found myself unable to agree with
him. Upon these and upon any other features of the Table
and of the entire paper I desire criticism and suggestions from
all who may interested.

II, 17, “%ssura Sylvit.—tin advocating the retention of this,
while objecting to eponyms in general since 1880, I am cer-
tainly open to the charge of inconsistency. The following
points should be borne in mind:—(1) Little personality or na-
tionality attaches to this name. (2) There are exceptions to

322 JOURNAL OF COMPARATIVE NEUROLOGY.

most rules (§260). (3) Even if my daszsylvian, presylvian
and subsylvian be rejected as titles of human fissures, there are
several fissures in animal brains that have for many years been
known by ‘‘sylvian’” compounds. (4) The substitute proposed
by the German committee, cerebri laterals, is rather general than
specific in suggestion. (5) If they are right in regarding the
fissure as collocated with the striatum (His, ’95, 170), then,
after the fashion of Azppocampal, calcarine and collateral, the
more appropriate term would be /zssura striatals.

Il, 74, 75, Gyrus subcollaterahs and G. subcalcarinus.—So
slight is the resemblance of these cortical strips to the forms in-
dicated in the commonly accepted szwz/e names, fuszformis and
lingualts, that I have never been able to remember their relative
locations. It seems probable that the fissural names calcarina
and collateralis are to persist. If so, is it not both logical and
convenient to designate the gyres just ventrad of them by loca-
tives indicating their positions, viz., G. subcalcarinus and G.
subcollateralis ?

II, 85, Sedlcus enterparietahks.—Prof. Sir William Turner or-
iginally named the fissure zxztraparictalis, and the same form is
employed in his last fissure paper (Jour. Anat. and Phys., Oct.,
1890). To more essential grounds for doubting the advisability
of applying any name to this ‘‘fissure complex,’’ must be added
the carelessness of printers and proof-readers, and even the ap-
parent ignorance of some writers as to the distinction between
enter and znira.

II, B, 2, and III, B, 10, Recessus aulae.—I may err in sup-
posing the zecessus triangularis of the German list to be identi-
cal with the vecessus aulae described by me in 1881 (’81, @).

II, B, 4, Parvacoca.—Even were there not adequate rea-
sons for replacing ventriculus in all neural names by coela, para-
coela is simply the Greek equivalent of ventriculus laterals, and
as such has equal privileges with the German heteronym
“« Sectenhodhle’’ which has been used heretofore and will hardly
disappear at once.

II, B, 18, LFxunentia occipitahs.—The name preferred by
the German committee, Bulbus cornu posterius, is bracketed in

Wiper, Weural Terms. 323

their list. As I have shown (’84, a, 373, and ’89, a, 143), at
a certain fetal stage the occipital fissure has a distinct ental cor-
relative and is hence entitled to be ranked as a total fissure, or,
according to the distinction proposed by the German com-
mittee, as a fissure rather than a sulcus. But in the adult the
general thickening of the walls commonly obliterates the orig-
inal elevation, and the ‘‘totality” of the fissure is not apparent.
This temporary existence of the essential character should per-
haps constitute a fourth objection to the distinction between
fissura and sulcus proposed by the German committee and dis-
cussed in §$121-122.

II, B, 37, /udustum.—This seems to have been omitted
from the German list. Its condition in man, chimpanzee,
monkey, cat and sheep has been discussed by Fish (’93, @).

II, C, 1, Cortex.—I am unable to see any good reason for
replacing this familiar and suggestive mononym by the ponder-
ous dionym, substantea corticals.

II, C, 14, Yapetum.—The original Latin is fapete, perhaps
from the Greek rays. The ending e occurs with so few anatomic
terms, e. g., ve¢e, that it is perhaps scarcely worth while to dis-
turb the established modern usage.

II, C, 21-23.—Why should these names of divisions in-
clude the genitive of the major part any more than with 10-14,
or 26-29?

Ill, 8, 9, Postgeniculum and Praegeniculum.—These loca-
tive names retain the essential features of the earlier polyonyms.
The parts are strictly caudad and cephalad of one another. The
more lateral aspect of the praegeniculum is due toa difference
in size.

Ill, B, 4, Horamen tnterventriculare.—This cavity, the aula
(S211) and two portas of my list (II, B, 2, 3), connects the
right and left ‘‘ lateral ventricles.’’ These are cavities of the
‘‘telencephalon” (my prosencephalon), not of the diencephalon.

III, B, 9, Praecommissura.—This is certainly prosenceph-
alic (‘‘telencephalic’’), and to include it among diencephalic

parts is as artificial as in the case of the ‘‘ foramen interventric-
ulare’”’ (III, B, 4).

324 JoURNAL OF COMPARATIVE NEUROLOGY,

§241. IV, 21, Cvus.—The fibrous mesencephalic masses
are mentioned ten times where the ‘‘stems”’ of the cerebellum
or olfactory bulbs are named once; hence the greater need of a
brief mononymic designation for the first; for the second and
third either the longer pedunculus or the addition of a qualifier
would prove less burdensome.

IV, 29, /utercalatum.—This locative mononym was sug-
gested by Spitzka in 1887; W., ’89, a, §103.'

V, 4, Sule? cerebelli.—For most of the interfoliar crevices
I proposed vzmula in 1889. But, as shown by Stroud, certain
of them are deep and merit the title of sw/cus. For the minor
crevices 77mula (or perhaps swlculus) may serve.

V, 6, Vallis.—For the grounds of preference for the briefer
basal word ($30) over the longer diminutive, see W. and G.,
89, 529, $75.

V, 12, Folia [ingulae|.—For the diminutive ‘‘leaflets”’
on the lingula no special name seems to be needed, and if it
were, vzucula alone would suffice.

V, 22, Prleum.—The substitution of this mononym for
hemisphaerium cerebeli was proposed by Dr. B. B. Stroud (’94);
on developmental grounds he recognizes a pracpileum and fpost-

pileum. Stroud’s ‘‘furcal sulcus”’ seems to be what is called

‘*preclival”’ in the last edition of Quain, III, Fig. 59. Other
features of the cerebellum described and figured by Stroud (the
cestus and several sulci, central, culminal, tuberal, pyramidal,
uvular and nodular) are not included in the present list.

V, 37, Medus avis.—The depression thus designated is so
seldom mentioned that the dionym is not burdensome. If C.
L. Herrick had not proposed zzdulus for nucleus the former
might be an acceptable mononym for the little ‘‘ nest.”’

1JIn the German list, between mesencephalon and their metencephalon (my
epencephalon), are enumerated nine parts under the head, ‘Isthmus rhomben-
cephali.’’ Their omission from the present table was accidental, and due to my
reversal of the original order of enumeration of the segments. I have already
expressed(Z197) my objection to the assignment of segmental value to this neck-
like region, and shall consider it hereafter (3250). Lemmnzscus is included in IV,
14and 15. Brachium conjunctivum [cerebelli| probably designates the praepe-
dunculus (V, 40). Velum medullare antertus is the valvula (IV, 35). For gang-
lion interpedunculare 1 prefer ganglion intercrurale, and for Nucleus trochlearis,
Nidus trochlearis,

Wiper, Neural Terms. 325

V, B, 36, Stratum cinereum.—Why not (in the German
list) stratum griseum, in accordance with the word employed
among the ‘‘ Termini generales ?” see §36.

VI, 1, Metepicoeha or ‘‘ ventriculus quartus.’”-—The divis-
ion of this continuous cavity into regions corresponding with
the two recognized segments (V, 1 and VI, 26) must be con-
sidered upon another occasion ($250).

VI, 25, M€edulla oblongata.—According to the German
committee this is coextensive with their myelencephalic segment
(my metencephalon), and the ventral portion of the segment
next cephalad (their metencephalon, my epencephalon) is con-
stituted by the pons. But the pons exists only in mammals ;
hence in the other vertebrates the cerebellar ‘‘ roof’’ would be
unsupported by a ‘‘floor;” see V, 2, preoblongata.

VI, 30, Pyramis.—The replacement of corpus pyramidale
and of processus clavatus (40) by pyramzs and clava respectively
was urged by Spitzka fifteen years ago (’81, @).

VI, B, 15, Macleus olivaris accessorius dorsals.—I\f dorsalis
be appropriate here, why not in several other cases where pos-
terior is employed by the German committee ?

$242. VII, JZyelon.—Respecting the substitution of this
mononym for the dionym medulla spinalis, which was proposed
by Owen just half a century ago, see §51. Owen also con-
sistently, although I think unwisely, employed the compound,
myelencephaton, for axis cerebrospinalts. Huxley applied it to
the last encephalic segment, and this misappropriation is
sanctioned by the German committee. Reserving comments
upon these points for another occasion ($250), I now claim that
the sole justification for the use of syelencephalon is the adop-
tion of myelon in the Owenian sense.

VIII, 32, Acervus.—This word, signifying a heap, occurs
in Andrews and Stoddard’s lexicon. The diminutive, acesvulus,
is longer, needless and of modern origin.

IX, Lloodvessels.—As admitted by me in 1884 (’84, ¢)
and restated in §§163 and 172, absolute mononymy is unattain-
able with large groups of organs, e. g., muscles, fissures and
vessels. Hence, excepting with crculus (A, g) and ‘orcular
(C, 8), with the single word adjectives in this category must be
understood avterza, stnus or vena; and when there is any danger
of ambiguity the substantive or its abbreviation should be
employed,

; (sparta jo
- uewesi1By ue
SI[BSiOp ‘9d {si aque ant
wnyy fsnuod] vijueaa Binssimm0; EOL SIN Bijaooojakyw| = uojakyw| uopadwl{rTA
wnt wnp xoqo {ey uojeyqdes) =v} eSu0]
-zadery featjo {stmeshg}-1urvidd onessnoaq|-nsiy ‘snaodejay snxo[deja Bpayejayy| = BIaooejay|-Uaiay |-qoisog [TA
uinjejuap ‘snjnsd04 uojeydas wn]
fsturiaa { e}esuo;qosrig suog epnsary snxo|didy ead vrjaooid q |-uodq -[2qa1agQ JA
wn}e[eo wn10}U9UE
-1ajul {snostumay {vj} |-9a} sauoijessnoap (Aoidaiey oy} uoyeygeo| wnurmes
-snio {uinjuemsea} fsnig 'B.INSSIMIUL0D}SOg B[NATeA Ul) Bla}OSa| BIye0sosay|-Uasay j-lupen?y) AT
e[noiues euseryo
‘stsXydida ‘sisfydod |: eanssrmwooipou uojeydas
-Ay f4aqny fcunaqiojsog| { vanssrummoovidng euoqeyy snxa|deiq Ba}VIG eI[20ovIq|-Ual ImMeleYy LITT
[ae aes See ee Se oy s (ovjaqyerrnd "(aet]a00 ele Per
snxodeaed yeroqey | [P1978] pus |-vivd [e107
siskyd X1U1OJ ‘uINso]]eo paar Vacoan BjazU[NeB [Vso | puv aeceee ss
-eied {mnyepneo fejn | (stpesodura} saved) vurts} feyed fay, = Sarpnyour) |°4}8uTpnyour) jayy Surpuyoar) | Uoreydas
-I1JU9] § B[NsUT fwintIT[eg BANSSIMMCI9BAgG|‘VIIqMIy ferusey snxa|dosoig B[9}OSO1g| vi[aodoso1g |-Uasoig wNIGs19aD/T]
(B110}0¥j[0 sized) Sees, uojeydas| m10j08y
uaul, { wniqimoavsg BANSSIWIWODIVIg zjaiouryy| PHP°CUIYY|-ueuryy [0 Iq[Ng IT
: ae _,| 40d uvrvgiy ; uousog sno P quaut \uanjezsuor
Spang sayjo aos “9 |*Ia CAUSED) Z pun uy, °9 SISNXIAT °F -uvaguay t Ayana °F | Say ce | fy 1

“SLIJIVAVYD 1dYJO OWOS PUL S}UIWSIG ALoYy} 0} Surps0s0v spiwvg [VnoN owog Jo Surdnoay [euowu0ig ‘TTA AIAVE

Witper, Neural Terms. 327

Commentaries Upon Table VII.

$243. Its purpose is two-fold :—(a) To indicate, accord-
ing to my present information and belief, the number and con-
stitution of the definitive encephalic segments. (4) To illus-
trate the verbal correlations between the names of the segments
themselves (column 2), and those of (3) their major cavities, (4)
their membranous parietes, and (5) their vascular plexuses.

$244. It is in some respects an amplification of the table
on p. 409 in W. andG., ’82. It differs from that in my later
paper (’89, @, 121) in (a) the recognition of the Rhinencephal
and (0) the vertical arrangement of the segments.

$245. From Schwalbe’s table (81, 397) it differs mainly
in the absence of any attempt to indicate the relative ‘‘ values ”’
of the several segments upon embryologic or other grounds.

$246. In this respect it differs also from that of His (’g5,
162). In this latter, moreover, I have not as yet succeeded in
recognizing consistency with (a) his other table on p. 158, (0)
the segmental arrangement employed in the German list of neu-
ral terms (80-87), (c) a discriminating use of terms, (d) due re-
gard for precedent, or (¢) the facts of comparative anatomy as I
interpret them.

$247. Conceding the high authority of Professor His as
to the embryology of man, I nevertheless believe it to be alto-
gether undesirable to infer the segmental constitution of the
vertebrate brain from the conditions presented during the devel-
opment of the human organ. Indeed, if the embryology of
other forms were also taken into account, the number of poten-
tial ‘‘neuromeres’”’ would be unmanageably large, even if any
two investigators could agree at present as to how many should
be recognized.

§248. While anticipating that the problems involved will
be eventually elucidated upon the basis of all the facts concerned,
I believe our present effort should be to agree upon a schema
of the vertebrate brain which, while not contravening the facts
of embryology, shall harmonize so nearly with the facts of com-
parative anatomy as to facilitate rather than obstruct an effort

328 JOURNAL OF COMPARATIVE NEUROLOGY.

to describe and interpret the conditions encountered in a given
brain.

$249. I freely admit my ignorance or non-comprehension
of certain points, and also that my views have varied somewhat,
particularly as to the segmental value of the olfactory region of
the brain. Nevertheless, I regard myself as justified in advo-
cating the schema presented in Table VII upon the following
grounds :—(1) For more than twenty years the general question
has never been long out of my mind; (2) with special reference
to it I have prepared and studied scores of brains of all classes
and most of the orders; (3) the subject has been discussed more
or less fully in papers by me’ upon the brains of many different
forms; (4) papers upon other forms’ have been prepared at this
institution ; (5) the schema has proved practically available for
research as indicated above, and has been readily comprehended
and remembered by even general students.

§250. What I advocate is that there be recognized for
the present six definitive segments of the vertebrate brain under
the titles Rhinencephalon, Prosencephalon, Diencephalon, Mes-
encephalon, Epencephalon* and Metencephalon. It is my in-
tention to review the whole subject at the coming meeting of
the Association of American Anatomists in May, 1897.

Part VIII. Concluding Remarks.

S251. A. Practical Suggestions.—As one of the older
American anatomists, and as having committed at least my
full share of terminologic errors, I venture to formulate some
suggestions of a practical nature for the benefit of the younger
generation.

Wee , Bibliography, (’75, ¢3. 776, a, 6, 63/7977, 4; 781, @5. 84,14, 085) Ogee
"87, a, 6, c; "80, @; "91, 0; ’93, a; ’96, 2d} W. &G., *82, chap. X.
*See papers by Clark, Mrs. Gage, Fish, Humphrey, Kingsbury and Stroud.
3Even if Osborn is correct in his interpretation of the cerebellum as

‘* primitively ” intersegmental (’88, 57) he nevertheless admits that it ‘ second-
arily acquires a functional importance equal to that of the other segments.”

oS Sa.

WILDER, WVeural Terms. 329

$252. Caution in Publishing New Terms.—It is true that
words needlessly introduced into anatomy have no such embar-
rassing permanency as is conventionally assigned to synonyms
in systematic zoology. Nevertheless, for a time at least, they
encumber current publications and dictionaries. Hence, how-
ever necessary and legitimate they may seem to the framer,
neither a new term, nor an old one in a new sense, should be
actually published without prolonged consideration, and con-
sultation with at least four individuals representing as many
categories of possible critics :—(a@) an investigator of the same
general subject; (0) an experienced teacher ; .(c) an earnest stu-
dent; (Z) a philologic expert whose admiration for the past
has not blinded him to the needs of the present and the future.

§253. Method of Introduction of New Terms.—As ‘‘ ur-
gently recommended ” by the A. A. A. S. Committee on Bio-
logical Nomenclature (§84), ‘‘ Whenever a technical word is
used for the first time, the author should give in a special note
(a) the Latin form, (0) the etymology, (c) the proper adopted
form or paronym for his own language, with the adjective, etc.,
when applicable, (@) as concise and precise a definition as
possible.”’

$254. Lndirect Responsibility for Latin Terms.—Even when
the foregoing admirable rule is not followed, the validity of the
following can hardly be questioned :—‘‘The introduction of any
derivative, oblique case, or national paronym renders the intro-
ducer responsible for the actual or potential Latin antecedent of
such word in accordance with the usual rules of derivation and
paronymy (§178).

$255. Paronyms versus Heteronyms.—Excepting with a
few conspicuous or particularly important parts, e. g., head,
heart, brain, e¢c. (§48), there should be employed either the
Latin (international) names, or the national paronyms ($46;
Tables Il and V). Itis quite true that ‘calling a millstone
by a Greek name does not enable us to see a whit farther into
it’”’; yet the designation of parts of the body by terms of classic
source, even if somewhat modified in form, enables the anato-

330 JoURNAL oF COMPARATIVE NEUROLOGY.

mists of other nationalities to apprehend the signification more
readily than they might from vernacular words.

§256. Homonyms.—As has been repeatedly observed
(§$23, 26, 68, etc.) the context commonly averts misapprehen-
sion as to words having two or more meanings. The proba-
bility of confounding the mouth with a bone is scarcely greater
than that of mistaking a mathematic fora urinary calculus. But
when a term or phrase possibly ambiguous is first introduced in
a given publication, and especially in the title, absolute ex-
plicitness should be attained, no matter how many qualify-
ing words may be required. In the title of a paper, the term
‘“cervical follicles’ is certainly ambiguous, and while ‘‘ mental
prominence’”’ as employed by Huxley is shown by the context
to designate a projection in the region of the chin, in a title it
might be readily misunderstood, particularly by a psychologist. *

§257. Consistency.—This ranks second among the desira-
ble attributes of all scientific writing which I have long called
the five C’s, viz., Clearness, Consistency, Correctness, Concise-
ness, and Completeness. The last may seldom be attained; the
lack of the first and second is as rarely excusable.” The prac-
tice of the virtue of Terminologic Consistency is tantamount to
avoidance of the vice of Pecilonymy (§$34-39).

§258. <Avordance of Pecilonomy.—Whatever doubts a wri-
ter may entertain as to the relative excellence, authority or
vogue of two or more synonyms, and however he may shrink
from committing himself to either one of them (§39), justice to

1 The title (‘‘On the fracture system of joints, with remarks on certain
great fractures”) of a paper just received (Bost. Soc. Nat. Hist. Proceedings,
XX VII) might at first sight seem to concern the surgeon quite as much as the
geologist.

2 While never really justifiable, obscurity of style may result from conditions
more or less difficult to avoid; let usassume that no scientific writer would delib-
erately formulate the doctrine credited by Jules Janin to Balzac. When asked the
meaning of a passage the novelist is reported to have replied ‘* Ceci pour le
bourgeois”, and to have explained that an unintelligible sentence or phrase now
and then had a good effect on the ‘‘ general reader’’, who, if the sense were al-
ways too obvious, might flatter himself that he was equal to the writer and on a
level with his thoughts.

—

ee

|
:

WILDER, WVeural Terms. 331

his readers, if not regard for their good opinion, should lead him
to make his selection in advance and to adhere thereto through-
out a given publication.’

§259. Abbreviational Methods.—The following rules are
recommended.

a. The abbreviation should indicate the Latin (interna-
tional) name. With all mononyms this will also indicate equally
well the national paronym; but with English and German polyo-
nyms (§47), the usual transposition of the adjective and substan-
tive renders the recognition less easy.”

b. Abbreviations should be formed regularly, and vowels
excluded excepting when the initial letter is such, or when their
absence might occasion ambiguity.

c. In the explanation of a figure abbreviations should be
set in alphabetic order. So natural, reasonable and just is this
rule that its disregard can only be attributed to the selfish assump-
tion upon the part of a writer that the time its observance would
have cost him is of more value to the world than the time its
non-observance costs all of his readers together, not to mention
the ill-effects of righteous indignation.

$260. Importance of Moderation.—As with biologic gen-
eralizations, there are few philologic rules without exceptions.
Yet the reformer, especially if young and enthusiastic, either
ignorant of history or undismayed thereby, ‘‘too often imagines

1 As stated in 355, the principle and method were adopted by me in 1880.
At that time Henle’s works were not known tome. But in 1884 I was so im-
pressed with his systematic employment of a single set of names that the first
step in the collaboration toward Foster’s Medical Dictionary (258) consisted in

photographing the ‘‘ Index’ of his ‘‘ Nervenlehre”’ and distributing copies for
discussion,

2 From my point of view this constitutes an argument for the conversion of
certain polyonyms into mononyms. For example, if the dionym commissura ana
terior be retained, the Latin and French abbreviation would bec. a., the English

a.c.,and theGermanv.c. But of the mononym, praecommissura, pre. would
probably serve in each case.

332 JouRNAL oF ComMPARATIVE NEUROLOGY.

that a principle, if right, cannot be carried too far ;’’’ (Barclay).
In this connection may be appropriately quoted the verse from
Horace :

“« Est modus in vebus ; sunt certi denique fines,
Ultra citraque nequit consistere rectum.”

§261. B. Suggestions to American Anatomists.—Circum-
stances have precluded the possibility of submitting either the
manuscript or the proofs of this article to other members of the
American committees. Hence their responsibility for its con-
tents must be limited strictly by their official recommendation
of certain terms or principles, and by the usages embodied in
their individual publications. I hope they will join in whatever
discussion of the general subject may be aroused by this article
freely and without apprehension that opposition to my views
will affect my personal or official relations. All I ask of them
is the clear recognition of all the conditions.

§262. Perhaps my own view of what the conditions really
are may be most conveniently introduced by a commentary
upon a varagraph in the address of the president of the Asso-

ciation of American Anatomists a year ago. Professor Dwight

said (’95):

‘*German anatomists have recently adopted a report prepared
by some of their number working in company with representatives of
other European countries. It is for us to consider whether this one can
be looked upon as accepted and whether it is acceptable ; whether we
can join hands with our foreign colleagues, or whether we can devise
an American nomenclature which shall be so much better that we can
disregard the inconvenience of a distinct standard. We have had
for years a committee on Anatomical Nomenclature, with Professor
Wilder for secretary, who has given so large a part of his busy life to
this matter. We may expect an important contribution to the matter
in the report of this committee.”

1 TlJustrations may be found in the record of my own terminologic progress,
Part II, in the rigid insistence at various stages upon the indispensability of
words in Latin form (1880-1883), and upon idionyms or terms absolutely free
from ambiguity (prior to 1895). Cerebrocortex and cerebellocortex were products
of the too general (and yet never sweeping) application of the principle of
mononymy.

ee

Wiper, Neural Terms. 333

$263. Dr. Dwight’s address was devoted mainly to what
he justly characterized as ‘‘a social question of the first impor-
tance, far transcending purely scientific discussion, vzz., the
methods of obtaining and utilizing anatomical material.” No-
menclature was considered briefly and almost incidentally. The
following commentaries are designed partly to reinforce some of
his remarks, and partly to avert possible misapprehension as to
both what he said and what he felt obliged to omit.

§264. Inthe first place, asa member of the committee
on Nomenclature of the Association of American Anatomists
since 1889 ($81), Dr. Dwight recognizes with especial clearness
that the subject can no longer be ignored. Now that a score
of European anatomists have given more or less attention to it
during six years, and have expended upon it about $2500.00,
no individual or association can hereafter treat it as insignificant.

$265. Secondly, the approximate completeness of the
German list of the visible parts of the entire body renders it a
substantial basis for discussion and a starting point for further
progress.

§266. The two conditions just named will, as doubtless
anticipated by Dr. Dwight, lead anatomic writers and teachers
to pay more heed to their terminology, and to maintain at
least a temporary consistency, z. ¢., within the limits of a single
lecture, article or treatise.

$267. Yet our gratification at the tardy German admission
of the need of terminologic improvement, and our recogni-
tion of the usefulness of the list compiled with such learning
and industry and at such expense, should not lead us to over-
look (a) the limitations of the German report in both intent and
performance ; (4) the delay in its adoption by other nations ; (c)
the qualifications of Americans for independent judgment.

8263. Phet oie. Ni Aa 2.0¢), the Wome Anatomica
adopted by the Anatomische Gesellschaft at Basel in 1895, is
regarded by the Germans themselves as provisional and subject
to modification. As stated officially (Anat. Anzeiger, Ergan-
zungsheft, X, 161), and by Prof. His (§$2, 228) there was ap-
pointed a standing committee of revision, which is to report

334 JOURNAL OF COMPARATIVE NEUROLOGY.

upon proposed changes and new terms at intervals of three
years.

§269. Although France and Great Britain were repre-
sented upon the general committee, no members from those
countries were present at the signing of the report and of the
declaration against the efforts of the American committees,
April 19, 1895 (Ana. Anz., Erganz., X, 162). Furthermore, as
frankly stated by Prof. His (95, 6-8), some of the French cor-
respondents preferred a different method of procedure, and the
English commission had not reported at all ($170). The im-
probability of universal and unqualified assent upon the part
of British anatomists is indicated by the following remarks of a
Glasgow professor (Cleland and Mackay, ’96, 3):

‘‘ With regard to the naming of individual structures it may: be
noted that more than one attempt has been made to impose uniformity
of nomenclature by the arbitrary authority of an individual or com-
mittee.? It may be doubted if any such attempt can possibly be suc-
cessful. The ‘‘ Nomina Anatomica ” of His (’95, @) is most impor-
tant for consultation; but the adoption of its recommendations in
this country (Great Britain) would, in a large number of instances, in-
volve the abandonment of good names in general use for others whose
advantages are not obvious.”

$270. Through its secretary the German committee de-

clared (Krause, ’91; $158, 7) that it intended to be ‘‘conser-_

vative in its action.”’ Now conservatasm is notoriously difficult
to define, and in respect to nomenclature its degrees may equal
in number those who have opinions upon the subject. , But

1 So far as appears in the official record (Avat. Anz. XII, Erganzungsheft,
1896)no reference to nomenclature was made at the last meeting of the Anatom-
ische Gesellschaft. Curiously enough, however, the title of a paper (pp. 153-
154) by Bardeleben, who signed the antimononym declaration of the ‘‘Nomen-
clatur Commission’ (%147),is ‘* Ueber das Praefrontale und Postfrontale des
Menschen’. I am not disposed to cite these two words as adjectival locatives
and as precedents for fostcava etc. (2181); but they are excellent mononymic
adjectives used as substantives, (#115) and they do not occur in the official list
adopted by the committee of which Bardeleben was a member.

2No such attempt is known to me. The very notion savors of ecclesiasticism
rather than of science. At the most, individuals have set certain fashions, more
or less commendable and permanent, while committees have made recommend-
ations which even their own members may disregard when their information is
increased or their views are modified.

eS ee ee

WILpvER, Neural Terms. 335

while the abolition of the vast majority of time-honored terms
has not been even hinted at in this country, I believe many
anatomists here and also in England have recognized earlier and
more fully than most of the Germans the existence of two con-
ditions (S190, F) that are essentially modern, viz., (a) the
enormous expansion of anatomic and physiologic knowledge ;
(b) its general diffusion among the people."

§271. Indeed, notwithstanding the declaration of conser-
vatism above mentioned, it is not easy for me to conceive that
all the members of the Anatomische Gesellschaft really antici-
pate the retention of, ¢. g., ‘‘manubrium sterni,”

ee
2 corpus
sterni

and ‘‘ processus xiphoideus ”’ for praesternum, mesoster-

WS

num and xiphisternum, respectively; of ‘‘squama occipitalis ”’
for (os) supraoccipitale ; of ‘‘arcus zygomaticus” for zygoma ;

” ’

of ‘‘latissimus dorsi,’’ ‘‘ biceps brachii ’’ and ‘‘ triceps brachii”
; Pp

for latissimus, biceps and triceps respectively; of ‘‘ processus ver-
miformis”’ for appendix ; of ‘‘substantia corticalis”’ for cortex ;
of ‘‘vena cava superior’’ and ‘‘vena cava inferior’, radix an-
terior’? and ‘‘radix posterior’, for terms not dependent for
appropriateness upon the erect attitude of the human body.
§272. In the declaration of the Anatomische Gesellschaft
($147), and in the warning of its oldest member (§208), it is
intimated that between the American and German committees
there already exists a terminologic crevice which further ad-
vance upon our part is likely to convert into an ‘‘impassable
culf.”” Taken by themselves, or in connection with the pass-

1 For nearly ten years, at Cornell University, the members of the general
classes in physiology, candidates for first degrees in Arts and Science, and num-
bering from 150 to 180 in each year, have individually examined, drawn and
dissected each the brain of a sheep. At the recent meeting of the American
Society of Naturalists, I outlined (’96,) a plan for the commencement of
practical studies of the brain in primary schools ; this in pursuance of the
conviction expressed seven years ago:

‘« Aside from prejudice and lack of practical direction as to removing, pre-
serving, and examining the organ, there is but one valid reason why every child
of ten years should not have an accurate and somewhat extended personal ac-
quaintance with the gross anatomy of the mammalian brain; that obstacle is
the enormous and unmanageable accumulation of objectionable names under
which the parts are literally buried.” W. & G., ’89, 282.

336 JouRNAL OF CoMPARATIVE NEUROLOGY.

ages just referred to, it seems to me that Dr. Dwight’s closing
words convey a similar gloomy impression, and that they pre-
sent alternatives too widely divergent.

$273. As may be seen from Parts IV and V, with the
single exception of the German retention of anterzor and foste-
rior ($$132, 192), between the German committee and the
American committees that had reported prior to the three ut-
terances referred to in the last paragraph, the actual differences
were simply trivial. Even the list adopted by the American
Neurological Association contains no unfamiliar term whatever."

$274. It must be remembered also that only neural terms
are here referred to. As well remarked by Pye-Smith (’77, 162)
and by His (’95, 155), encephalic nomenclature stands most in
need of revision and offers peculiar difficulties. With the other
regions of the body the conditions and necessities are far sim-
pler. Hence there is no probability that any action of Ameri-
can committees respecting anatomic nomenclature as a whole
could eventuate in the establishment of what could be regarded
justly as a ‘‘separate standard.” A stronger phrase for the
hypothetic contingency could hardly be employed were the dif-
ferences between the two sets of names comparable with the
distinctions between the metric system and the English weights
and measures.

$275. The address of Dr. Dwight contained no reference
to what has already been accomplished or proposed by Ameri-
can organizations. At that time, of course, the action of the
American Neurological Association had not been taken. But
the Association of American Anatomists and the American
Association for the Advancement of Science (§$81-85) at vari-
ous periods between 1889 and 1892, had adopted unanimously
the recommendations of their three committees corresponding
with the first five sections of the report of the A. N. A. (§80).

1The allegation of Professor His that my individual ‘* proposals tend to cre-
ate a language entirely new and for the most part quite strange,” has already
been met (7204). In matters non-scientific a deliberate exaggeration of like ex-
tent would probably receive a briefer and less euphemistic characterization.

WILpvER, WVeural Terms. 337

§276. Although the specific terms included in these
recommendations are few, they exemplify all the commendable
features of the German report. Indeed, I fail to discover in
the latter any general statement, principle, rule or suggestion
that had not already been set forth with at least equal accuracy,
clearness and force in the writings of British and American
anatomists prior to 1895.

§277. Notwithstanding the small number of individual
terms included in the American reports, the dates of appoint-
ment of the committees, 1885, 1889, 1891, the representative
nature of the terms, and the comprehensiveness of the general
recommendations, all justify deliberate and independent action
upon the part of anatomists in this country. Hence it is grati-
fying to see Dr. Dwight’s indication of our duty in this regard.
He evidently advocates neither heedlessness nor a servility
that might merit the application of the following caustic com-
ment in an English review of an American work:

‘¢ Our authors are merely following the lead of a certain eminent
German anatomist, it being a fashion with American scientific writ-
ers (except a few who prefer a sort of scientific Volapiik! ) to follow
pretty blindly the German scientific leads in the matter of nomenclat-
ure, and this even to the extent of bodily adopting actual German
words into a language which can already find two or three synonyms
for almost any word it may be desired to translate. No doubt many
English authors are also to blame in this respect, but the fact is none
the less to be deplored.”? Mature, Aug. 13, 1896, 341.

$278. It seems to me that in America the present condi-
tions are particularly favorable to deliberate thought and inde-
pendent: conclusion upon the subject of this article. The pro-
fessors of anatomy in some of the larger medical schools are
young and vigorous. Few if any are rightly to be reckoned as
‘‘old,”’ or at any rate as too old to change their minds and

1Histologic terminology was apparently referred to here; but I imagine
that the remark might apply equally to my series of correlated names for one of
the encephalic segments and some of its parts, viz., metencephalon, metacoelia,
metatela, metaplexus and metaporus; see Table VII.

°The writer of a letter in the Waszon for Oct. 8, 1896, declares that ‘‘ there
is a reaction setting in in America against extreme Germanization, and that it
has not come too soon.’”’ For a comparison of the national Az/age with the in-
Abie proton, and a citation of Aristotelian precedents for the latter,
see $212.

338 JOURNAL OF COMPARATIVE NEUROLOGY.

their modes of expression when occasions arise.’ In view of
all the circumstances, the attitude appropriate for American an-
atomists, desirous to cOoperate yet maintaining their independ-
ence and self-respect, is indicated in the following lines of Lu-
cretius :

Judicio perpende: et st tibt vera videntur,

Dede manus: aut si falsum est, adcingere contra.

§279. Those anatomists who are either interested already
in the improvement of nomenclature, or whose regard for their
successors leads them to sacrifice some present time and effort
in their behalf, are urged to read upon the subject, to reflect,
to confer, and to correspond freely. So intimate is the rela-
tion between verbal expression and mental operation that, even
when we imagine ourselves above such weakness, criticism of
the former too often means disturbance of the latter. Hence, as
with other matters involving individual habit and preference, an
actual interview may sometimes be less productive of good than
a correspondence that eliminates more completely the personal
element and affords opportunity for reflection and for consulta-
tion with disinterested experts.’

§280. Those who may entertain? a not unnatural impa- -

tience at the apparently slow progress made in this country,
and who may even feel mortified when comparing the two score
terms adopted by the American Neurological Association with

1The following incident encourages the belief that such changes of both
opinion and custom may occur at any age. While preparing the new edition of
his ** Anatomy’? (’89), Leidy preferred central lobe or tsland of Keil; but later,
at the age of sixty-six, as chairman of the committee on nomenclature of the
Association of American Anatomists, he signed the report recommending zusu/a,

2Nearly all my letters and ‘slips’’ (278, note) from anatomists and linguists
in this and other countries have been preserved. Always instructive and often
encouraging, the restraining and even destructive quality of some might have
been endured with less equanimity at a personal conference; see 371, and ’gI, 4.

3That such sentiment, if entertained, has not been communicated to me,
either directly or indirectly, constitutes one of the many evidences of the tolerant
and helpful spirit that has animated American anatomists in dealing with the
confessedly perilous qnestion as to how independent thinkers may best commu-
nicate with their fellows.

Ee

Wiper, Neural Terms. 339

the forty-five hundred recommended by the Anatomische
Gesellschaft, may well consider :

First, the improbability that any competent. American
anatomist could have been diverted from his regular duties long
enough to accomplish what was so effectively done by the sec-
retary of the Anatomische Gesellschaft.

Secondly, the enormous advantage afforded by the complete
list adopted by the Gesellschaft. Many dead or dying terms
have been disposed of, and the ‘‘ decks have been cleared”’ for
more efficient action.

Thirdly, whatever precipitation, vacillation, and error may
be condoned in individuals whom volition or circumstances may
lead to assume untenable positions, organizations legislating in
the interest of posterity should advance so slowly as to risk
neither recession nor even deflection. The Germans themselves
regard their comprehensive list, as a whole, as provisional.
The American selections (§$80, 238) constitute, we may be-
lieve, an immortal forty.

§281. Were neural terms to be now devised de novo, the
hippocamp would certainly receive some less fantastic designa-
tion, and the great cerebral commissure would be much more
likely to be called tvabs (a beam) than corpus callosum. But both
callosum and hippocampus are embalmed, as it were, in several
other names and they are not sufficiently objectionable to war-
rant their revolutionary annihilation. The best we can do is to
effect a tolerable compromise between the imperfect conditions
that we have inherited and the ideal conditions that we should
like to transmit to our successors. 7

The anatomists of to-day have an opportunity of providing
for the future while cherishing the past; of benefiting poster-
ity without neglecting ancestors; of lightening the burdens of
generations to come, while recognizing the value of what was
done by the anatomical fathers: of erecting a terminologic
monument in which the best of what has been is cemented by
their own labors.

340 JouRNAL OF CoMPARATIVE NEUROLOGY.

Part IX, Bibliography.

In addition to papers directly referred to in the text there
are included some in which are used the simplified terms of
description or designation recommended by the present writer.
A single asterisk indicates a partial, two a thorough, adoption
of the system. Had other than neurologic papers been in-
cluded there would appear in the second category papers by
J. H. Comstock, S. H. Gage, G. S. Hopkins and many others.

The names of certain periodicals are abbreviated as follows :

A. A. A., Proceedings of the Association of American
Anatomists.

A, A. A. S., Proceedings of the American Association for
the Advancement of Science,

A. N., Transactions of the American Neurological Asso-
ciation.

A. P. S., Proceedings of the American Philosophical So-
ciety of Philadelphia.

Handbook, Reference Handbook of the Medical Sciences,
A. H. Buck, editor, g volumes, 1884-1893.

J. C. N., Journal of Comparative Neurology.

FN; Deka: of Morphology.

J. N. M. D., Journal of Nervous and Mental Disease.

AYERS, Howarpb, ’93.—Anatomical nomenclature. Letter to
the editor. Science, XXI, 190-191, April 7, 1893.

BAKER, FRANK, ’84.—The rational method of teaching anatomy.
New York Medical Record, April 19, 1884, 421-425. Six figures.

BarKER, L.F., ’96.—Concerning neurological nomenclature.
Johns Hopkins University Bulletin, V11, 200-201, Nov.-Dec., 1896.
*95.—The nomenclature of nerve cells. A. A. A., 1895,

409-44.

Barclay, JOHN, ’03.—A new anatomical nomenclature. O., pp.
182. Edinburg, 1803.

*KBROWNING, W., ’89.—Vessels of the brain. Handbook, VIII,
231-244, I pl., 3 figs., 1889.

oa ’93.—Vessels of the brain. J/dem, IX, 138-141, 1 fig.,
1893.

*KCLARK, TRAcy E., ’96.—Comparative anatomy of the insula.
J. C. N., VI, 59-100, 5 plates.

i ee a

Wiper, Neural Terms. 341

CLELAND, JoHN, and Mackay, J. Y., ’96.—Human anatomy,
general and descriptive. O. pp. 833, 630 figs., London and New York,
1896.

Cougs, E., and SHute, D. K., ’87.—Neuro-myology. Mew
York Medical Record, XXXII, 93-98, 121-126, July, 1887.

*DonaALDSON, H. H., ’90.—Anatomical observations on the brain
and sense organs of the blind deaf-mute, Laura Bridgman. Amer.
Jour. Psychology, III, 293-342, 2 plates. Sept., 1890.

Dwicut, T., ’95.—Our contribution to civilization and to science.
Address as president of the Association of American Anatomists, Dec.,
1895. Proceedings of the eighth meeting, 12-15. Also in Science,
Ill, 75-77, Jan. 17, 1896.

’ Epincer, L., ’93.—Vorlesungen iiber den Bau der nervésen
Centralorgane, des Menschen und der Thiere. 4th ed., O., pp. 220,
145 figs. Leipzig, 1893. (In Table V the reference to this work is
incorrect).

*kFIsH, P. A., ’90.—The epithelium of the brain cavities. Amer.
Soc. Microscopists, Proceedings, 140-144, 1 plate, 1890.

ay ’93, @.—The indusium of the callosum. /. C. W., III,
61-68, 1 plate.
ot ’93, 6.—-The terminology of the nerve cell. A. A. A.,

May; 1894.) Also. Covi EN 70075:

ao ’95 —The nervous system of Desmognathus fusca. J. M.,
X, 231-286, 4 plates.

ek *96.—A note on the cerebral fissuration of the seal
(Phoca vitulina). A. A. A., 1895, 61-64, 1 plate. Alsoin J. C. W.,
VI, 15-18, 1 plate, March, 1896.

Foster, F. P., ’88-’94.—An illustrated encyclopedic medical dic-
tionary. Being a dictionary of the technical terms used by writers on
medicine and the collateral sciences in the Latin, English, French and
German languages. Q., 4 vols., Mew York, 1888-1894.

*KGAGE, Mrs. S. P., ’93.—The brain of Déemyctylus viridescens
from larval to adult life, and comparisons with the brain of Ama and
Petromyzon. <‘“* The Wilder Quarter-Century Book,” 1893, 259-313,
8 plates.

AK ’95.—Comparative morphology of the brain of the soft
shelled turtle (Amyda mutica) and the English sparrow (Fasser domes-
tica). Proceedings Amer. Microscopical Society, XVII, 185-228, 5 plates.

7% —’96.—Modification of the brain during growth. Ab-
stract of paper read before the 4. 4. A. S., Aug. 24, 1896. Amer,
Naturalist, XXX, 836-837, October, 1896.

342 JOURNAL OF COMPARATIVE NEUROLOGY.

GouLp, G. M., ’96.—Concerning medical language. Address at
meeting of Amer. Medical Editors’ Association, May, 1896. <‘‘Bor-
derland studies,” O., pp. 380, Phil., 1896.

HENLE, J.,’79.—Handbuch der Nervenlehre des Menschen.
<Handbook der Systematischen Anatomie des Menschen. 2nd. ed.,
O., pp. 666, 327 figs., Braunschweig, 1879.

*HERRICK, C, J., ’91.—Studies in the topography of the rodent
brain. Bull. Lab. Denison Univ., VI, 26-46, 22 plates, June, 1891.

* °93, a@.—Recent advances in the study of the nervous
system. Kansas Acad. Sci., Trans., 1893.

‘93, 6.—Illustrations of the surface anatomy of the brain
of certain birds. /. C. &¥., III, 471-176,: 1/plate, \Dec., 1893:

a3 ’94.—The cranial nerves of Amblystoma punctatum. J.
GinN., IV, 193-207, 2 plates. ‘Dee, 2894.

*HERRICK, C. L., ’90.—The central nervous system of rodents,
Preliminary paper. Bull. Sct. Lab. of Dentson University, V, 35-96,
19 plates. June 1890.

* ’91, a —Illustrations of the architectonic of the cerebel-
lum. /. C. W., I, 5-14, 4 plates, March, 1891.

* 91, 6.—Topography and histology of the brain of cer-
tain reptiles. 7. C. WV., I, 14-38, 2 plates, March, 1891.

* 91, ¢.—Topography and histology of the brain of cer-
tain ganoid fishes <Contributions to the comparative morphology
of the central nervous system. /. C. V., 149-182, 4 plates, June,
1891.

= ’91, d.—Contributions to the morphology of the brain of
bony fishes. /. C. WV., I, 211-245, 333-358, 3 plates, Oct. and Dec.,
1891. :

*, *91, e.-—The commissures and histology of the teleost
brain. Anat. Anzeiger, VI, 676-681, 3 figs., 1891.

* ’92, a.—Notes upon the anatomy and histology of the
prosencephalon of teleosts. American Naturalist, 112-120, 2 plates.
Feb., 1892.

** ’92, 6.—The cerebrum and olfactories of the opossum.
YG. JV., 11, 1-20, 3 plates.) Bebi,) 1e92.

* ’92, c.—Studies on the brain of some fresh-water fishes.
J.C. N., II, 21-72,:2 plates. May, 1&92.

* ’92, d.—Histology and physiology of the nervous ele-
ments. /..C..4V.,:II,:137-148, Dec.,. 1892.

* ’92, e.—Embryological notes on the brain of the snake.
J. C. N., Il, 160-176, 2 plates. Dec., 1892.

Wiper, Neural Terms. 343

o 92, £—Additional notes on the teleost brain. <Anat.
Anz., VII, 422 431, ro figs., 1892.

*k ’92, g.—Notes upon the histology of the central nervous
system of vertebrates. <W&. Leuckhart’s ‘‘ Festschrift.” Pp. 278-288,
2 plates. 1892.

* ’93, a.—Topography and histology of the brain of certain
reptiles. /. C. M., III. 77-106, 119-140, 11 plates. June, Septem-
ber, 1893.

* ’93, 6.—The callosum and hippocampal region in marsu-
pial and lower brains. /. C. W., III, 176-182, 2 plates, Dec., 1893.

* ’93, c.—Recent progress in the comparative anatomy of
the nervous system. Handbook, 1X, 669-696, 78 figs.

His, W., ’80"85.—Anatomie menschlichen Embryonen. Text,

O. I, pp. 184, 17 figs.; II, pp. 104, 67 figs; ILI, pp. 260, 156 figs.;
Atlas, F., XIV plates. Leipzig, 1880, 82, 85.
’9s.—Die anatomische Nomenclatur. Nomina anatomica,
Verzeichniss der von der Anatomischen Gesellschaft auf ihrer IX.
Versammlung in Basel angenommen Namen. Eingeleitet und im
Einverstandniss mit dem Redactionsausschuss erlaiitert. Archiv fur
Anatomte und Physiologie. Anat. Abth., Supplement Band, 1895.
O, pp. 180; 27 figs., 2 plates, 1895.
’96 —Herr Burt Wilder und die Anatomische Nomencla-
tur. Anat. Anzeiger, XII, 446 448, Oct. 30, 1896.

HuGuENIn, G., ’79.—Anatomie des centres nerveux. Traduit
par Keller; annoté par Duval. O., pp. 368, 149 figs. Paris, 1879.

*k HUMPHREY, O. D., ’94.—On the brain of the snapping turtle
(Chelydra serpentina.) J. C. N., IV, 73-116, 3 plates.

Huxtey, T. H.,’73.—Manual of the comparative anatomy of
vertebrated animals. O., pp. 431, 110 figs., Mew York, 1873.

HyrttL, JosEPH, ’80.—Onomatologia anatomica. O., pp. 626,
Wien, 1880.

*kK rncsBurRY, B. F., ’95.—The brain of Mecturus maculatus. /.
C. V., V, 138-206, 3 plates.

KoELLIKER, A., ’g2.—Nervenzellen und Nervenfasern. Diol.
Centralblatt, XII, 33-51. Jan, 30, 1892.

96. Handbuch der Gewebenlehre des Menchen. Sechste
Auflage. Zweiter Band. Nervensystem des Menschen und der
Thiere. O., pp 874, 845 figs. Letpzig, 1896.

Krause, W., EDITOR, ’79.—Specielle u. macroscopishe Anatomie
<Handbuch der menschlichen Anatomie, von C. F. T. Krause. O.,
pp. 1054, 570 figs. Hannover, 1879.

344 JouRNAL OF COMPARATIVE NEUROLOGY. |

KRavsE, W., ’9t, a2.—Myologische Nomenclatur. O., pp. 4.
Gottingen. June, 1891. (As secretary of the committee of the
Anatomische Gesellschaft).

’91, 6.—On anatomical nomenclature. Lritish Assoctation
Report, 1891, Aug., 1891. Also Jntern. Monatsch. f. Anat. u. Phys.,
1892, IX.

*LEIDY, JOSEPH, ’89.—Human anatomy. Second edition, O.,
PP. 950, 495 figs. Philadelphia, 1889.

*MILLs, CHARLES K., ’86.—Arrested and aberrant development
of fissures and gyres in the brains of paranoiacs, criminals, idiots and
negroes. Preliminary study of a Chinese brain. Presidential address.
A. N., 1886. J. N. M. D., XIII, Sept. and Oct., 1886, 37 pages,
2 plates.

Minot, C. S., ’92.—Human embryology. R. O., pp. 815, 463
figs. Mew York, 1892. :

ONvuFROWICS, ’87.—Das balkenlose Mikrocephalgehirn Hofmann.
Arch. f. Psychiatrie, XVIII, 305-328, 2 plates, 1887.

*Osporn, H. F., ’83.—Preliminary observations upon the brain
of Amphiuma. Phila. Acad. Nat. Sci , Proc., 1883, 177-186, 1 plate.

ss -84.—Preliminary observations upon the brain of Menop-
oma and Rana. Phila. Acad. Nat. Sci., Proc., 1884, 262-274, 1
plate.

*k —’88.—A contribution to the internal structure of the
Amphibian brain. /. JZ, II, 51-96, 3 plates. July, 1888.

Owen, R., ’46.—Archetype and Homologies of the vertebrate
skeleton. British Association Report, pp 169 340, 1846.
°63.—Monograph on the aye-aye. Zoological Transactions,
V, 33-102, 12 plates. ;
°68.—On the anatomy of vertebrates. III, Mammals.
O., pp. 915, 614 figs. London, 1868.

PaRKER, T. JEFFERY, ’82.—Notes on the anatomy and develop-
ment of Scymnus lichia. New Zealand Institute Transactions, XXV,
222-234, 2 plates. Read Aug. 15, 1882; issued May, 1883.

’84.—A course of instruction in zootomy. D., pp. 397,
72 figs. London, 1884.

* °86.—On the nomenclature of the brain and its cavities.
Notes from the Otago University museum. JVature, XXXV, 208-210,
2 figs., Dec. 30, 1880.

Pye-SmituH, P. H., ’77.--Suggestions on some points of anatom-
ical nomenclature. Journal of Anatomy and Physiology, X11, 154-175,
Oct, 5577.

WILDER, Neural Terms. 345

*Ricocs, C. E., ’90.—Editor of American edition of Edinger’s
*“Vorlesungen.” O., pp. 230, 133 figs. Philadelphia, 1890.

SCHWALBE, G., ’81.—Lehrbuch der Neurologie. <Hoffmann’s
Lehrbuch der Anatomie des Menschen. O., pp. 1026, 505 figs. Er-
langen, 1881.

*®SORENSEN, A. D., ’93, a4. —The pineal and parietal organ in
Phrynosoma coronata. J. C. WV., III, 48-50, 1 plate, June, 1893.

* "93, 6.—Vhe roof of the diencephalon. 7. C. W., III,
50-52, June, 1893. ©

*SPITZKA, E. C., ’81, a.—Letter on nomenclature. Science, (ed-
ited by J. Michel), April 9, 1881. Alsoin 7. MV. MZ. D., July, 1881,

661-662.
*

’81, 6.—Further notes on the brain of the sauropsida.
Science, May 28, 1881, 254.

* ’81, c.—Notes on the architecture of the oblongata. WJ.
Y. Medical Journal, Sept., 1881, pp. 10, 1 plate.

** 84, a.—The morphological status of the cerebellum. JV.
Y. Medical Record, XXVI, III, July 26, 1884.

of 84, 6.—Hippocampus vs. hypocampa. WV. Y. Medical
Record, Sept. 20, 1884, 335.

* "84, c.—Contributions to the anatomy of the lemniscus.
NV. Y. Medical Record, XXVI, 393-397, 421-427, 449-451, 477-481,
16 figs. Oct. and Nov., 1884.

5 84, d.—Mittheilung, die angebliche Abwesenheit der
Vierhiigeltheilung bei Reptilien betreffend. Veurol. Centralblatt, 1884,

pp. 4.
*.

’86.—The comparative anatomy of the pyramid tract.
Jour. Comp. Medicine and Surgery, Jan., 1886, pp. 47, 24 figs.

* —'88.—The oculo-motor centres and their codrdinators.
J. N. M. D., Aug., 1888, pp. 20, 6 figs.

* ’89, a.—Histology of the brain. Handbook, VIII, 164-
189, 40 figs., 1889.

* ’89, 6.—Spinal cord. Handbook, VIII, 474-484, 14 figs.
1889.

* ”*90..—Remarks on the brain of the seals. Amer. Natur-
alist, XXIV, 115-122, Feb., 1890.

*KSTOWELL. T. B., ’82.—The vagus nerve in the domestic cat.
A. P. S., XX, 123-138, 3 plates. Read July 15,1881; printed, March,
1882.

sas ’85.—[Outline of practical work in vertebrate zoology.]
This was, as I recollect it, the substance of the title. My copy is lost;

346 JOURNAL OF COMPARATIVE NEUROLOGY.

the busy author has none, and cannot even recall the place of publi-
cation, probably in an educational journal.

Solera 86, a.—The trigeminus nerve in the domestic cat. A.
P. S., May 21, 1886, 459-478.

eK —’86, 6.—The facial nerve in the domestic cat. 4. P.
S., Nov. 5, 1886, 9-19, 1 fig.

ae —’88.—The glosso-pharyngeal, the accessory and the
hypoglossal nerves in the domestic cat. A. P. S., XXV, pp. 89-104,
3 plates, March 2, 1888.

eK —’gt.~ The lumbar, the sacral, and the coccygeal nerves
in the demestic cat. /. C. WV., I, 287-314, 1 plate.

*STRONG, OLIVER S., ’95.—The cranial nerves of amphibia. //.
M., X, 101-203, 6 plates, 1895.

**STROUD, B. B., ’95.—The mammalian cerebellum. Part I,
The development of the cerebellum in man and the cat. /. C. M.,
V, 71-118, 8 plates, 1895.

*TicHT, W. G, ’90.—[As junior author with C. L. Heriekh
The central nervous system of rodents. Preliminary paper. ulle-
tin of the scientific laboratories of Denison University, V, 335-396, 19
plates, June, 1890. |

*TURNER, C. H., ’91.—The morphology of the avian brain. /.
C. NV., I, 39-92 ; 107-132; 265-286, 9 plates, March, June, October,
1891.

Waters, B. H., ’91.—Additional points on the segmentation of
the vertebrate brain. Zoolog. Anzeiger, 1891, 141-144, May 4, 1891. -

WERNICKE, ’81.—Lehrbuch der Gehirnkrankheiten. O., 3 vols.,
Kassel, 1881.

WHEWELL, W., ’40.—History of the inductive sciences. 1840.

*WRIGHT, R. Ramsay, ’?84.—On the nervous system and: sense
organs of Amiurus. Canadian Institute Proceedings, N.S., 352-386,
4 plates. October, 1884.

* ’°85.—Article ‘‘The anatomy of vertebrates.” <The
Standard Natural History, III, pp. 52, 44 figs. Boston, 1885.

W. &G., ’82.—[WitpErR, B. G., and Gacer, S. H.|—Anatomi-
cal technology: an introduction to human, veterinary and compara-
tive anatomy. 1882, O., pp. 600, 120 figs., 4 plates. [Chap. X,
comprising more than roo pages, 4 plates and 16 figures, represents an
original investigation upon the brains of /Vecturus and the Cat. ]
’86.—The same, second edition, revised.

’92.—The same, third edition, from the second.

WILDER, Neural Terms. 347

’°89.—Anatomical terminology. Handbook. VIII, pp. 24,
2 figs,, 1889.

Wiper, B. G., ’71.—Intermembral homologies, the correspon-
dence of the anterior and posterior limbs of vertebrates [1871]. Bos-
ton, Proc. Nat. Hist. Soc., XIV, 1872, pp. 154-188, 309-339, 299-
420; 5 figs. .

73, 6.—The outer cerebral fissures of Mammalia (especi-
ally of the Carnivora), and the limits of their homologies. 4. A. A.
Se M2873, (pt. 2) app) 214-2347; inoitis.

73, c.—Cerebral variation in domestic dogs and its bear-
ing upon scientific phrenology. A. 4. A. S., XXII, 1873, (pt. 2), pp.
234-249; 6 fig.

73, d@.—Lateral asymmetry in the brains of a double hu-
man monster. 4A. A. A. S., XXII, 1873, (pt. 2), pp. 250-251; 4 fig.
°73, k.—The pectoral muscles of mammalia. A. JA. A.
aL 1873% pp.s05-707-

75, c.—Notes on the American Ganoids. IV. On the
brains of Ama, Lepidosteus, Actpenser and Folyodon. A. A. A. S.,
XXIV, 1875, pp. 151-193 ; 3 plates.

°76, a@.—On the brains of fishes. . Phil. Acad. Nat. Sct.
Proceedings, XX XVIII, 51-53, April 4, 1876.

*76, 6.—Note on the development and homologies of the
anterior brain-mass with sharks and skates. Amer. Jour. Science,
Series LID Xi, roz-2055 1 fig.» 1876:

76, ¢.—On the brains of some fish-like vertebrates. A. A.
BAd 51); ) SEXO, LO 710, ep p. 259-259-

*77, a.—On the brain of Chimera monstrosa. Phil. Acad.
Proc., XX1X, May 29, 1877, pp. 219-250; 1 plate.

80, 6.—The cerebral fissures of the domestic cat (élis
domestica). Sctence, 1, 49-51, 2 figs.

80, d.—The foramina of Monro; some questions of ana-
tomical history. Boston, Med. and Surg. Jour., CIII, 152-154, 1880.
’80, e.—The foramina of Monro in man and the domestic
cat. 4. A. A. S.; WV. Y. Medical Record, XVIII, 328, 1880.

80, f.—Partial revision of the nomenclature of the brain.
A. A. A. S.; N. Y. Medical Record, XVIII, 328, 1880.

"80, g.—The crista fornicis, a part of the mammalian brain
apparently unobserved hitherto. A. A. A. S, 1880; WV. Y. Med.
Record, XVIII, 1880, p. 328.

’*81, 5—A partial revision of anatomical nomenclature,
with ‘especial reference to that of the brain. Sczence, II, 1881, pp.

348 JOURNAL OF COMPARATIVE NEUROLOGY.

122-126, 133-138, March. Also 7. WV. WZ. D., July, 1881, 652 661.
81, c.—How to obtain the brain of the cat. Science, II,
1881, pp. 158-161.

81, d.—The brain of the cat (Felis domestica). A prelim-
inary account of the gross anatomy. A. P. S., XIX, 1881, pp. 524-
562; 4 plates. Read July 15; published in December.

’83, ¢.—On the brain of a cat lacking the callosum. [4.
A. A. S., 1879]. A. WV. A., 1883. Amer. Jour. Neurol. and Psychi-
atry, 1883, II, pp. 491-499: 4 fig. /. V. and M. D.,N.S., VIII,
1883, p. 62 (Abstr.); Veurol. Centralblatt, 11, 517 (Abstr.)

—’83, d.—On the alleged homology of the carnivoral Fissura
cructata with the primatial /. centralis. A. N. A., 1883. J. WV. M.
De MN. S., VIIL, 1883; -pp.°62-63.

84, a.—Methods of studying the brain. The ‘‘ Cart-
wright Lectures ” for 1884. MV. Y. Med. Journ., XXXIX, 1884, pp.
141-148, 177-183, 205-209, 233-237, 373-377, 457-461, 513-516, 653-
656; XL, 113-116; 64 fig. Abstractsin VV. Y. Med. Record, XXV,
1884, Pp. 141-143, 197-199, 225-227, 365-367, 449, 450, 545, 546.
84, 6.—Names and synonyms. Privately printed in con-
nection with ’84, a. O., pp. 7, Feb., 1884.

°84, c.—On encephalic nomenclature. A. WV. A., 1884.
JANAGM. D., 1884, pp. 18, 50; abstract:

*84, d.—Do the cerebellum and the oblongata represent
two encephalic segments or only one? A. A. A. S., XXXIII, 1884.
Science, IV, 1884, p. 341; WM. Y. Med. Journ., XL, 1884, p. 324.
"84, ¢.—On some points in anatomical nomenclature. A.
A. A. S., XXXIII, 1884.

"84, —The existence and dorsal circumscription of the
porta (‘‘ Foramen Monroi’’) in the adult human brain. A. 4..A. S.,
XXXII, 1884; WV. VY. Med. Journ., XL, 1884, p. 324.

84, g.—The relative position of the cerebrum and the
cerebellum in the anthropoid apes. A. 4. A. S., XXXIII, 1884.
85, a.—The use of slips in scientific correspondence. Soc.
Natural. East. U. S., 1884. Sctence, V, 1885, p. 44.

85, 6—Encephalic nomenclature. I. Celian terminol-
ogy: the names of the cavities of the brain and myelon. WV. Y. Med.
Journ., XI, pp. 325-328, 354-357, Mar. 21 and 28, 1885; 8 fig.

’85, c.—Paronymy versus heteronymy as neuronymic prin-
ciples. Presidential address at the 11th annual meeting of the Amer.
Neurological Assoc., 1885. A.W. S., J. NV. M. D., XII, pp. 21.
Abstr. in Meurolog. Centralblatt, Dec. 15, 1885.

WILDER, Neural Terms. 349

85, d.—Educational museums of vertebrates. Address
(as vice-president) before the Biological section of the Amer. Assoc.
INGV Ob SCIENCE. (Ae ALANS. | XOX S553) pp. 19. Abstract in
Science, Sept. 11, 1885, pp. 222-224.

’85, ¢e.-—On two little-known cerebral fissures, with sug-
gestions as to fissural and gyral names. A. WV. A., 1885. /. WV. W.
D., 1885, XII, pp. 3. (Abstr. in LVeurolog. Centralblatt, Dec. 15
1885.)

F)

85, f.—On a seldom-described artery (4. termatica), with
suggestions as to the names of the principal encephalic arteries. A.
BVCA TS85:. J. Vat PD: 1885. Kil pp) 2: \(Abstractsin 7.) Y-
Med Journ. and NV. Y. Med. Record, June 27, 1885, and in Meurolog.
Centralblatt, Dec. 15, 1885).

°85, g-—The names of the encephalic arteries. WV. Y. Med.
Jour., Nov. 28, 1885.

85, 4.—Neuronymy. WV. Y. Med. Record, Aug. 1, 1885,

p. 139.

*86,a.—The collocation of a suture and a fissure in the
human’ fetus: \/.\V. 47. D.,)'1886;: XULL, pp. 6, 1 fig. ( Abstracts
in WV. Y. Med. Record, July 31, 1886, Science, Aug. 6, 1886, and Mea-
wcal News, Aug. 7, 1886.

’86, 6.—Notes on the brain. /. W. AZ. D., 1886, XIII,
pp. 4. (Abstracts as in a.)

~86, c.—Exhibition of the medisected, alinjected head of
amundercr. A, WV.°At, 1886. J. NVM DL XIN, p.633, (Ab-
stracts as in @.)

86, d.—Remarks upon a living frog which was decere-
brized more than seven months ago. 4. WV. A., 1886. /. NV. M.D.,
XIII, p. 30. (Abstracts as in a.)

’86, e.—The paroccipital, a newly-recognized fissural inte-
ger of. Vi: PD Oe. pp. ins, is figs../1 886:

’86, f—The paroccipital fissure. Letter to the editor.
WNW Wed. Record, Oct: 2, 1886) pp. ssoi3o0:

86, g-——Human cerebral fissures, their relations and
names and the methods of studying them. American Naturalist, XX,
Pp. go1-902, r plate. Oct., 1886.

°87, a.—The dipnoan brain. (Abstract of a paper on the
brain of Ceratodus, with remarks unon classification and the general
morphology of the vertebrate brain, read by invitation before the
National Academy of Sciences, April 22, 1887). American Natural-
ist, June, 1887, XXI, 544-548, 3 figs.

350 JOURNAL OF COMPARATIVE NEUROLOGY.

'87, 6.—Remarks on the classification of vertebrates.
Amer. Naturalst, XXI, 913-917, Oct. 1887; (Abstract in 4. 4. A. S.,
Proc 1887, 251.)

’87, c.—Correction of the foregoing. Letter to the
editor. Amer. Naturalist, X XI, 1887, 1033.

"88, a.—The relation of the thalamus to the paracele,
(lateral ventricle). A. M. A.,'1888, 313-320. Also J. WV. M. D.,
July, 1889, XIV, pp. 436 443, 2 figs.

—’88, 6.—The needlessness of corpus with striatum and of
opticus with thalamus. Letter to the editor. /. WV. M. D., Sep-
tember, 1888.

’*89, a.—Brain, gross or macroscopic anatomy of. Hand-
book, VIII, pp. 58, 104 figs. 1889.

—’89, 6.—Brain, malformations of, which are morphologi-
cally instructive. Same, pp. 6, Io figs.

’89, c.—Brain, removal, preservation and dissection of.
Same, pp. 7, 5 figs.

—’89, d.—The relation of the thalamus to the paracele, es-
pecially in the apes. A.A. A., 1889. (See also Note on p. 317 of
88, a.)

’89, ¢.—The heart as the basis of an intrinsic toponymy.
Wied. A... TS86, p25.

’90, a.—Do the Barclayan terms cause obscurity? Letter
to the editor. Science, April 4, 1890, p. 224.

?90, ¢.—Remarks on the brain of Chauncey Wright, with
commentaries upon fissural diagrams. 4. MV. A., 1890. /. WV. M.D.
Nov. 1890, pp. 2. :
—’go, e.—Exhibition of diagrams of the brains and medisect-
ed heads of man and achimpanzee. A. A. A. S., 1890. Abstr. in
Amer. Naturalist, Oct. 1, 1890, 980.
—’go, f£.—Exhibition of diagrams illustrating the formation
of the human Sylvian fissure. A. A. A. S., 1890.

—’go, g.—Owen’s nomenclature of the brain, with sugges-
tions based thereon. A. A. A., 1890.

—’go, 4.—Macroscopic vocabulary of the brain, with syno-
nyms and references. Presented to the Assoc. of Amer. Anatomists,
Dec..29, O., pp. 13, 1890.

—’g1, a.—The fundamental principles of anatomical nomen-
clature. Zhe Medical News, 708-710, Dec. 19, 1891.

—’g1, 6.—The morphologic importance of the membranous

Ls lO rh ee

Se ee a, eS

Wivper, Neural Terms. 351

or other thin parietes of the encephalic cavities. 7. C. WV., I, 201-
203, 189g.

—’g2.—American reports on anatomical nomenclature,
188g-1890, with notes as‘secretary. O., pp. 4, 1892.
—’93, a.—The gross or macroscopic anatomy of the brain.
Fandbook. Pp. 99-111; 10 figs. 1893.
93, 6.—Methods of removing, preserving, dissecting and
drawing the brain. /dem, pp. 111-121, 2 figs.
93, ¢.—Meninges. (The envelopes or membranes of the
brain and spinal cord). /dem, pp. 606-616, 11 figs.
93, d.—The metapore (Foramen of Magendie) in man
and apes. A. WV. A. Abstract in Phil. Med. News, Oct. 14, 1893.
—’94, a.—Exhibition of a suicide’s brain with two pistol-ball
wounds; remarks on its fissural anomalies. /. WV. JZ. D., Dec. 1894,
pp. 4. Alsoin A. WV. A., 1894, 102-105, and WV. Y. State Med. Soc.
Trans., 1874, 190 194.
—’94, c.—Problems connected with the cerebral fissures.
A. A, A., 1894, 32-35.

——’95, 4.—The progress of paronymy. Letter to the editor.
Science, May 10, 1895, 515-516.
—g5, 6.—The paroccipital fissure, should it be recognized,
and under that name? A. A. A., 1895, pp. 69-70, 2 figs.
—’g95, ¢.—The cerebral fissures of two philosophers. A. A.
1895, 71-73, 1 fig.
—’95, @.—The frog was not brainless, but decerebrized.
Letter to the editor. Sczence, June 7, 1895, 632.
—’95, ¢.—Meuron, neuraxis, etc. Discussion of paper of F.
Baker, ’95, a. A. A. A., 1895, 44-45.
—’95, 7.—Dissection of the sheep’s brain: being part IV of
‘¢ Physiology Practicums,” with plates XVIII-XXV and an append-
ix on the removal and preservation of the brain. 1895.
—’96, a.—‘‘ Pontine” or ‘‘pontile”? Letter to the editor.
Medical Record, (N. Y.) XLIX, 823, June 6, 1896.
—’96, 6.—The names epiphysis, conarium and corpus pineale :
correction of an error. Letter to the editor. Sczence, N. S., N., 1896.
—’96, ¢.—A matter of terms. Letter to the editor. N. Y.
Medical Journal, April 11, 1896, 489.
—’g6, d.—The dorsal sack, the aulix, and the diencephalic
Bexure, A Ve, T8060.) fe At, 2. Aug, Tego. p. 54g." 7. C. 2V.;
VI, June, 1896, 128.

A.

~

352 JoURNAL OF COMPARATIVE NEUROLOGY.

————’96, e.—The ectal relations of the right and left parietal
and paroccipital fissures. A. N., 1896. /. V. AZ. D., Aug., 1896,
543.04. C. V.,; VI, June, 1896, 229. Abstr: in WV. VY. WMedwal ieee
ord, July 11, 1896, 61.
—’96, f.—Some neural and descriptive terms. Circular let-
ter. Sctence, Dec. 25, 1896, 947. Also in WV. Y. Medical Journal,
Jan. 2, 1897; Anatomischer Anzeiger, 1897.
—’96 g.—The desirability and the feasibility of the acquisi-
tion of some real and accurate knowledge of the brain by precolle-
giate scholars. Amer. Soc. Naturalists, 1896. Sczence, 1897.

Additions and Corrections.

There are more items under this head than there might have been had it
always been practicable to let me see a revised proof. Ordinary errors of typo-
graphy and punctuation are not specified.

es line 4: For VII, read VI.
eye tz, Lue) Aue For VI, vead VII.

P. 230, note 1; After 84, insert ’86.

P. 230, note 2, last line, fifth word: For many, vead neural.

P. 253, last line: “or collosum, vead callosum.

2147, line 7: Mor Anzeizer, read Anzeiger.

The next three items are trivial in themselves but necessary for the main-
tenance of the accuracy of reproduction of the original as announced on p. 268,
note 3.

P. 269, fifth line from bottom : Coelia has a capital initial.
P. 269, note 1: Between Medical and News isa period. The words be-
tween 1890 and 1889 are italicized. The y of February should be omitted.

P. 273: The section now numbered 577 should constitute part of 176; For
9178, read 2177. 4

. 275, seventh line from bottom: For poslcaval, vead postcaval.

P. 279, seventh line: For diffussion, vead diffusion.

P. 293, Table V, 30: For 89, 153, read ’93, 196.

2235: For certain accidental omissions from the German list, see 7241, note.

Pp. 304-307, head-lines: For ’82, read ’81.

P. 306, Il, B: For Corum, vead Eorum.

2239, e, line 7: For trapezoides, vead trapezoideum.

P, 322, II, B, 4, Paracoelia: Of course the equivalency of this word for
ventriculus lateralis involves the acceptance of the adjectival force of the prep-
osition, para ; 7180-190.

P. 326, Table VII, column 8, segment VI, trapezium: That this part is
here included in the last segment, while in Tabie VI, V, B, 20, it is left in the
fifth, as by the German committee, exemplifies the difficulty of assigning parts
to these two segments.

#254, last line: The section here referred to is on p. 274, not the one wrong-
ly numbered 4178 on p. 273.

7268, line 1: Omit the periods between BRIN PAS

4268, line 5: After His, read (92; ’96).

Hat note, line 5: After 96, insert ¢.

- 340, Title 4: This should be the second under Baker, not Barker.

JOURNAL OF COMPARATIVE NeEvuroLoGy, Vou. VI. PLATE XIV.

FE. C. KENYON, PHOTOGR.

JouRNAL OF COMPARATIVE NEuROLOGY, VoL. VI. PLATE XV.

F. C. KENYON, PHOTOGR.

JoURNAL OF CoMPARATIVE NEuROLOGY, VoL. VI. PLATE Saves

F. C. KENYON, PHOTOGR.

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PiatTe XVII.

Jeunngs OF COMPARATIVE NEuROLOGY, VoL. VI.

F. C. KENYON, GEL.

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EIMERARY NOTICES:

Effects of Alcohol on the Cortical Nerve Cell.)

The tendency apparent of late to concentrate the attention upon
limited problems of neuro-physiology and attempt their solution by the
various improved methods now at our command is bearing fruit in
investigations promising to give us definite and reliable data for pathol-
ogy and psychology. Naturally none of these problems has greater
practical and theoretical importance than that respecting the causes and
character of cortical degeneration.

Dr. Berkley has sought to contribute to the solution of this prob-
lem by minute studies of the changes in the cortical cell produced by
the long-continued administration of alcohol to rabbits. 5 to 8 cc. of ab-
solute alcohol were fed to the animals and the dose continued until
their death perhaps a year after the beginning of the experiment. The
specimens were hardened in alcohol or Miiller’s fluid. Nissl’s method
and hematoxylin-eosin staining for cellular structures and blood-vessels
followed alcohol hardening and an original process, the Miiller’s fluid.
(The reviewer can but express surprise that methods known to induce
such shrinking and alteration in the cell bodies should have been
employed for hardening). The process referred to is as follows :

‘«'The cerebra are treated with Miiller’s fluid until the tissue is of
sufficient consistency to admit of fairly thin sections. The portions of
the brain selected are then cut into pieces not more than three milli-
meters in thickness, and the slices are immersed in a mixture of 3 per
cent. solution of bichromate of potassium, and 1 per cent. solution of
osmic acid, in the proportion of too parts of the former to 20 parts of
the latter. In this mixture the slices lie from three to five days, are
then removed from the fluid, and slightly dried on filter paper to re-
move any superfluous bichromate, are washed for a few minutes in a
weak solution of silver nitrate, and then go into the second or staining
mixture, which is made by adding two drops of a ten per cent. solu-

IBERKLEY, H, J. Studies on the Lesions produced by the Action of Cer-
tain Poisons on the Cortical Nerve Cell.—1. Alcohol. Brain, IV, 1895.

ii JOURNAL OF COMPARATIVE NEUROLOGY.

tion of phosphomolybdic acid to each 60 cc. of one per cent. argentic
nitrate solution in distilled water. The second solution is made only as
needed and at the moment before placing the brain tissue in it.”

This method is said to avoid the perplexing fringe of brown about
the impregnated cells and is rather a stain than a precipitation. It is
said to be more reliable also.

Unaltered cells fall into several groups: arkyochromic cells, with a
reticular arrangement of the chromophilic particles ; stichochromic cells,
with the particles in rows ; cytochromuc cells, with large nucleus and small
cell body ; somatochromic cells, with much protoplasm and small nucleus.
The cortical cells are chiefly somatochromic of the stichochromic va-
riety.

In the normal brain the contour of the vessels is regular and the
perivascular spaces are narrow but distinct. The nuclei of the walls
are sharply stained. In the alcoholic brains the small capillaries are
shrunken and irregular. ‘The nuclei are swollen and absorb more stain.
The perivascular spaces are enlarged and are either empty or partly
filled with hzmatoidin debris. In the somatochrome cells the nuclei
are altered in the disposition, size, and regularity of contour of the nu-
cleolar chromophilic particles.

By the silver method Berkley claims to show that all the pyramidal
cells of the cortex and many of the irregular and dngular ones have
short rectangular or oblique projections or gemmulz given off from the
protoplasmic processes and that these are not as Kélliker supposed ab-
normal or artifacts. Besides these the nerve cells have upon their
branches a small, though variable number of varicosities.

The neuroglia cells have nodosities in their fibres which must be
carefully differentiated. Making all possible allowances for artifacts
and variability the author feels justified in considering a considerable
number of the appearances in the silver preparations of alcoholic brains
abnormal. ‘The principal lesions are diminution in size, shrinkage of a
vast majority of the cortical cells, disappearance of the gemmule, cer-
tain swellings of the neurodendrites, and roughening of the stronger
processes, and to some extent of the cell body. It is a question
whether cells undergoing degeneration are as readily impregnated as
the normal. Our own experience would lead to the conclusion that
active processes, whether normal or pathological, favor reactions while
an inert condition due either to fatigue or disease predispose to rejec-
tion of the stain.

Tumefaction of the neurodendrite and a loss of the gemmulz go
hand in hand during degeneration. The method employed seems to

a

eee

Literary Notices. ili

be ill adapted to bring out the lesions of the cell body, though such an
instance as that shown in Fig. rr proves that the changes are similar to
those ordinarily seen in alcoholic dementia where the cell body is exca-
vated or irregularly vacuolated. It is a pity that comparison was not
made with cells stained with- hzematoxylin-sublimate-fuchsin or some
histological stain after complete hardening in chrom-acetic or sublimate.

In the cerebellum similar changes were found in Purkinje’s cells
but of a more marked character. It is certainly placed beyond ques-
tion by this study that alcohol, in common with other irritants, pro-
duces a very definite destructive effect on the nerve cells and in particu-
lar upon those of the kinesodic system. Gree Vee

Structure of Nerve Cells after Electrocution.!

The fatiguing effect of the prolonged action of weak electric cur-
rents on the cells of the nervous system is well known through the re-
searches of Hodge, Mann, and Vejas. Are these structural changes
increased by the shorter action of much stronger currents, is the ques-
tion which Dr. Fish set before himself for solution. The first speci-
men examined, a portion of the cervical spinal cord of a victim of an
electrocution at 1740 volts, exhibited a pronounced vacuolation of the
nerve cells not to be accounted for by any known conditions prior to
the execution. A second case in all essential respects similar and with
absolutely fresh material gave, however, negative results, there being
no observable lesions in the nerve cells of the same region of the spinal
cord under the same method of preparation. The latter case is re-
garded by Dr. Fish as the typical one and is verified by the results of
experimental electrocutions on the lower animals performed by Dr.
Krauss of Buffalo. Dr. Fish is inclined to the hypothesis that death
by electrocution is the result of the fixation of the cells of the central
nervous system, that is the cells are killed instantly in practically their
normal relations. Ci jee

Cortical Pathology of Permanent Dementia.’

Dr. Berkley has advanced a theory of the pathology of dementia
which is based on the recent advances in our knowledge of the relation

1FISH, PIERRE A. The Action of Strong Currents of Electricity upon
Nerve Cells. Jour. Nerv. and Mental Disease, N. S., XXI, 1, Jan., 1896; Zrans.
Am, Microscopical Soc., X XVII, 1896.

*BERKLEY, H. J. A Theory of the Causation of Permanent Dementia.
Medical News, 9 Nov., 1895.

iv JOURNAL OF COMPARATIVE NEUROLOGY.

of nerve cells and fibres in the central nervous system, the details of
which Dr. Berkley has himself so successfully investigated. He calls
attention to the fact that non-medullated nerve fibres are not known to
occur to any great extent in the cerebral cortex and expresses the belief
that the uncovered free endings of the lateral buds or gemmules of the
‘‘ psychic” cells of the cortex are the media of communication from
one neuron to another. These gemmule-bearing protoplasmic processes
are the first to suffer from the ravages of disease, the cell body degen-
erating later and the axis cylinder being affected last of all. ‘In
short, therefore,” to quote from a recent editorial in the Journal of the
American Medical Association, ‘‘ the theory of Berkely as to the pathol-
ogy of dementia is as follows: The conduction of nerve stimuli to the
cell corpus is through the medium of the lateral gemmules of the proto-
plasmic processes ; that these are specially liable to injury from toxic or
morbid influences, and are the first portions of the neuron to atrophy
and disappear in certain diseases of the brain; that with their atrophy
and consequent loss of function we have, first, confusion and incoér-
dination of psychic functioning, and finally with any widespread de-
generation of the cortical elements a permanent dementia ensues. His
conclusions have been deduced partly from examinations of human
brains and partly from experimental investigations on animals. He
gives with his paper a reproduction of micro-photographs, showing the
normal primordial process of a well educated man taken from an au-
topsy immediately after death, and of a corresponding process from a
subject of terminal dementia, showing the atrophy and absence of the
dendritic gemmules.” Coaiagtts

The Functions of the Frontal Lobes.!

The satisfactory discrimination of the functions of the frontal lobes
from those of other cortical areas is a matter of great difficulty and the
attempts hitherto made have produced only ambiguous and conflicting
results. Ferrier has decided that the frontal lobes preside over atten-
tion while also presiding over motions of the eyes and head. Munk
and Luciani consider this region as a part of the Fiihlsphzere or senso-
rium and the motor centre of the dorsal muscles. Wundt and Hitzig
from a theoretical standpoint assume that it is the centre of higher psy-
chical functions.

The author of the paper before us reaches similar conclusions and
offers interesting experimental evidence which if not entirely convinc-

IBIANCHI, L. Brain, IV, 1895.

Literary WNNotices. Vv

ing, is at least very suggestive. One must of course be on his guard
against attributing to the loss of brain substance phenomena which may
be due to the stimulating or depressing effects of operation or resulting
encephalo-meningitis. .

The details must be sought in the original but, in general, in the
case of monkeys after ablation of both frontal lobes, the behavior is al-
tered, the physiognomy is stupid and less mobile, the expression is _al-
tered and devoid of flashes of intelligence, curiosity or sociability.
There is no evidence of affection or gratefulness. Actions of purpos-
ive character are liable to be left incomplete. ‘There is loss of cleanli-
ness and discrimination. ‘The disposition is fitful and cruel.

The author denies the existence of a special centre of inhibition or
attention but concludes that the frontal lobes are seats of codrdination
and blending of outgoing products of the several sensory and motor
areas of the cortex. ‘‘ The frontal lobes would thus sum up into series
the products of the sensori-motor regions, as well as the emotive states
which accompany all the perceptions, the fusion of which constitutes
what has been called the psychical tone of the individual. ‘The removal
of the frontal lobes does not so much interfere with the perceptions
taken singly as it does disaggregate the personality, and incapacitate for
serializing and synthesizing groups of representations.”

“

(CACTI
Cerebral Localization.

To the surgeon whose duty it is to diagnose and treat lesions of
the central nervous system the present state of the theory of cerebral
localization is perplexing enough. He sees some denying the fact of
cerebral localization zz fofo and insisting that the cortex acts as a unit;
others who recognize the cortical areas essentially as located in the text-
books urge that the division of these areas into sensory and motor is a
false division, for all of the areas are really sensory, the motor zones
exerting no control over the muscles commonly associated with them,
but only receiving sensations of muscular and general sensations from
those regions of the body; and yet all of the time our leaders in sur-
gical practice are operating successfully on the basis of the old charts
constructed on the theories of Munk and Ferrier. In view of this sit-
uation a recent paper by Dr. C. K. Mills! offers a few timely suggest-
ions. We quote the latter part of the paper:

‘‘ For the practical purposes of the physician and surgeon, no

IMitts, C. K. Cerebral Localization in the Light of recent Pathologic
Researches. Jour. Am, Med. Assoc., XXVI, 1, 4 Jan., 1896.

vi JOURNAL OF COMPARATIVE NEUROLOGY.

matter what view may be taken of the nature of the processes going on
in the cortex, it would seem best to still hold to the view of the sepa-
rate localization of areas for the special senses, for motion, and even
for muscular and cutaneous sensibility. Lesions of these areas produce
phenomena of vision, audition, motion, sensation, etc., which are not
produced when the lesions are situated outside of the special areas to
which the functions above mentioned are assigned. The fillet radia-
tions for cutaneous and muscular excitations, as a compact bundle,
probably reach, or most closely approach, the outer layer of the cortex
in the postero-parietal convolutions and in the limbic lobe. Whether
we should regard the cells and fibers which bring about communication
between these regions and the motor cortex as true sensory terminals or
as simply constituting a field of conjunction, the only cortical and sub-
cortical lesions which will produce pure and marked sensory symptoms
will be those occurring in these areas. ‘These incoming messages,’
says Andriezen, ‘ which inform the brain of the movement of the limb,
arrive (strictly speaking ) not in the pre-Rolandic but in the post-Rol-
andic (ascending parietal) convolutions. In the pre-Rolandic or
ascending frontal convolution, and in the adjoining posterior portions
of the three frontal convolutions as well as the prolongation of these
areas on the mesial (marginal) convolution, we find the last term in
the cortical series, the finally disposed executive mechanisms.’

“¢ Tt would perhaps be best to define the cortical area for cutaneous
and muscular sensations, as that part of the cerebrum where the fillet
radiations most nearly approach the surface of the brain, before their
final ramifications in the molecular layer, still holding to the old view
with reference to the motor cortex. Andriezen, as already stated,
speaks of the pyramidal and ambiguous cells as the first sensory cells
of the cortex, because the terminals of the fillet radiations, or their ex-
tensions, first touch the apical processes of these cells, and therefore
these cells first receive sensory impressions from the periphery of the
body. It would be better, following Forel and Nansen, to disregard
entirely the subdivision into cells of sensation and motion, and take
the broad ground that we are simply dealing with the greatest and high-
est of sensori-motor areas, and that in the region posterior to the area
usually recognized as motor, the last stage in the sensory process is
reached, while in the Rolandic cortex the first stage in the motor por-
tion of the process begins.”

Ci aes

Literary Notices. vii

Motor Functions of Dorsal Spinal Nerves.

The question proposed in this investigation is, ‘‘ Do the dorsal
spinal nerve roots carry functional motor fibres for the splanchnic mus-
culature, on the one hand, and on the other hand, for the musculature
of the bladder, which is also derived from the lateral plates?’ The
investigations of van Wyhe and Hatschek have shown that this is true
for selachians, Amphioxus and Ammoceetes ; does it also hold for the
higher vertebrates ?

The dorsal roots of the spinal nerves of the frog were electrically
excited with a Du Bois Reymond’s apparatus and the results controlled
by means of mechanical stimuli of these roots. Such stimulation
evoked peristaltic and and anti-peristaltic motions of the digestive tract,
and it was demonstrated that the successive pairs of roots correspond
to distinct, though not sharply defined successive regions of the diges-
tive tract. This result stands in pleasant harmony with the recent work
of Sherrington and others on the segmental distribution of the cuta-
neous nerves. ‘The innervation is bilateral and the reaction persists after
the cessation of the stimulus. The time intervening between the begin-
ning of the stimulus and the first noticeable reaction varies; it is never
less than three seconds. ‘These reactions are independent of the vagus
or vagus centres. Study of the ventral roots showed that no motor
fibres go to the digestive tract from the spinal cord through any of the
ventral roots except fibres to the rectum from the sixth and seventh.
For the details of the connections of the several roots and of the very
interesting relations of the nerves of the rectum and bladder the orig-
inal must be consulted. The reader will notice that these results stand
in harmony with the anatomical discoveries of Lenhossék and others
who have described centrifugal fibres in the dorsal roots.

Cae.

Spiral Fibres in the Invertebrates.’

Ganglion cells are described in the ventral nerve chain of Htrudo
medicinalis which are essentially similar to those known in the sympa-
thic system of amphibians and reptiles. The spiral fibre breaks up
into a reticulum upon the body of the ganglion cell and the author de-
scribes this reticulum as consisting of two parts, one extra-cellular, the

1 Srernacu, E. and Wiener, H. Motorische Functionen hinterer Spinal-
nervenwurzeln. Arch. f. d. ges. Physiologie, LX, p. 539.

2 Simon, C. Sur l’existence de la cellule a fibre spirale chez les invertébrés.
Bibliographie Anat., 111, 6, Dec., 1895.

viii JOURNAL OF COMPARATIVE NEUROLOGY.

other intra-cellular. The former is regarded as a reticulum of origin,
not of termination, the individual fibres apparently arising within the
cell and uniting to form the spiral fibres, which is considered to be a
cellifugal prolongation of the subjacent ganglion cell. On the other
hand the intra-cellular reticulum is composed of filaments of the same
optical properties as those which go to make up the greater process of
the ganglion cell and the author suggests that they are the cellipetal fibres
which on entering the cell body spread through it and form an intra-
cellular superficial reticulum which in some way is to come into phys-
iological relations with the extra-cellular cellifugal reticulum. We shall
await with interest a more full description and confirmation of the pre-
liminary account of relations which are certainly sufficiently remark-
able to justify a little hesitation in giving them an unqualified accept-
ance without the most rigorous proofs.
C.Seike

Structure of the Thalamus.!

Corpus Luysit, or nidus hypothalamicus of man. This receives
fibres from the tractus opticus, which come chiefly from Meynert’s com-
missure. Apparently Gudden’s commissure also sends fibres into the
nidus hypothalamicus. The latter receives other fibres from the lenti-
cular nidus which penetrate it from the lateral aspect and also from the
tegmental bundle of the caudatum. Finally there is to be mentioned
a commissure of the nidi hypothalamici on the dorsal side of the most
caudal portion of the mammillaria.

Opticus termint. In the mouse, termini of the opticus fibres were
found in the corpus geniculatum laterale, in the thalamus itself and in
the corpus quadrigeminum anterius. In the two first mentioned the
termini are like those described for the lobi optici of birds, that is, with
much branched, compact terminal tufts which lie partly in the interior
of the corpora geniculata lateralia and of the thalamus and partly in the
stratum zonale of the latter. In the corpus quadrigeminum anterius,
on the other hand, no such tufts were found but endings loosely
branched over a larger area, which spread from the second white layer
especially into the outer grey zone. In young rabbits were found in
the layer of the tractus opticus laterally of the thalamus large cells
which send their nervous processes centrifugally into the tractus. It
was impossible to determine whether these fibres pass to Gudden’s com-

1 KOELLIKER, A. vy. Zum feineren Baue des Zwischenhirns und der Regio
hypothalmica, Verh. Anat. Ges., IX Vers., 1895.

Literary Notices. ix

missure or whether they represent the centrifugal fibres found by Cajal
in the retina.

Coronal fibres of the thalamus. Investigation of young mammals
shows that these fibres in the main present terminal arborizations in the
thalamus. ‘The optic radiations, however, undoubtedly terminate in
the cortex, as their cells of origin lie among the ends of the opticus
fibres.

Fasciculus thalamo-mammillarts, s. Vicg @ Azyr. In new born and
young mice it was clearly shown that the fibres of this bundle exhibit
terminal arborizations in the nidus dorsalis thalami. This bundle, which
according to the researches of Gudden has nothing to do with the pil-
lars of the fornix, must therefore take its origin in the cells of the cor-
pus mammillare—according to Gudden in the caudo-ventral nidus.

Pedunculus corporis mammillaris of the rabbit. The fibres of this
bundle undoubtedly arise in the large-celled lateral nidus of the corpus
mammillare. Of their termini nothing has hitherto been known. The
author finds, however, that they end cephalad of the pons in the re-
gion of the caudal end of the ganglion interpedunculare near which
they lie, surrounding dorsally and in part also penetrating a round nidus
already described by Gudden as lying behind the trochlearis nidus in
the central grey, the ganglion dorsale tegmenti of K6lliker. Another part
of these fibres ends in the central grey which surrounds this nidus.
From this nidus and from the central grey around it there arises the
dorsal longitudinal bundle of Schiitz which Kélliker has called the dorsal
grey longitudinal bundle, and this may be easily followed in longitud-
inal sections along the dorsal side of the fourth and third nidi and in a
curved course along the floor of the third ventricle.

Columnae fornicis of the rabbit. These tracts plainly pass only
through the lateral part of the corpus mammillare and end crossed be-
hind and on the dorsal side of the latter. The author has followed these
fibres to the nidus of the oculo-motorius, the posterior commissure and
the nidus ruber, though these relations are not definately established
and the real termini he is not at present prepared to state.

Ganglion habenulae of mammals. The fasciculus of Meynert
arises in the ganglion habenulae of the opposite side in free non-med-
ullated arborizations. The fasciculus of Meynert contains fine and
coarse fibres, of which the latter possibly pass above the ganglion into
the pons. In the ganglion interpedunculare arise the medullated fibres
discovered by Ganser which pass in two bundles ventro-dorsally and
end in the ganglion tegmenti dorsale and in the adjacent central grey.

Stria medullaris of the rabbit. This ends for the most part in the

x JOURNAL OF.CoMPARATIVE NEUROLOGY.

ganglion habenulae and derives its fibres, (1) from the fornix and the
Ammonshorn ; (2) from the basal part of the third ventricle, from the
regio supra-optica, where the fibres in question arise in a large ganglion
which is connected with the nidus of the basal bundle of Ganser; (3)
from the stratum zonale of the thalamus; (4) from the interior of the
thalamus. ‘The stria thins out from before backward and behind passes
over into the commissure of the pineal, from which a small number of
fibres enters into the pineal. This commissure is a union of the
habenulae.

Fasciculus longitudinalis dorsalis of Kélliker. The so-called dorso-
median fasciculus ends in the mammals cephalad of the nidus III in
ascending fibres which in part form a commissure, in part apply them-
selves to the medullary zone on the medial side of the nidus ruber.
A nidus of this bundle such as was found by Van Gehuchten in fishes
cannot be demonstrated in the mammals.

C.gpeee
The Lateral Line System of Amphibia.

Dr. Kingsbury has performed a service which will be appreciated
by many students in several departments of research in mapping the
exact distribution of the lateral line organs of many of our types of
tailed Amphibia, as well as of some of the allied forms. Descriptions
and figures of the following species are given, JVecturus maculatus,
Amblystoma punctatum, Protopterus annectens, Amphiuma means, Gyrin-
ophilus porphyriticus, Diemyctylus viridescens, Siren, Rana, Cryptobranch-
us allegeheniensts, Lepidosiren paradoxa, as well as comparisons with
several other types. The histology of the neuromasts ( Nervenhiigel )
is briefly discussed. We quote a few paragraphs.

‘«’The Amphibia afford in certain respects peculiar opportunities
for the study of a sensory system associated with existence in the water.
This is due to the fact that there are here included forms purely aquatic
-and forms as purely terrestrial in their habits of life, and yet others
which spend a portion of their life in the water and a portion of it on
land. In every family of the tailed Amphibia native in the United
States the system has been found, and in five families of the tailless
Amphibia. Since Malbranc has found the sense organs in a larval
Pipa, and Leydig ina larva of the viviparous Salamandra atra taken
from the oviduct of the mother, doubtless the system will be found in

1 KinGspury, B. F, The Lateral Line System of Sense Organs in some
Amphibia, and Comparison with the Dipnoans. Zvans. Am. Microscopical Soct-
ety, XVII, 1896.

Literary Notices. xi

a more or less perfect state of development in all Amphibia at some
period in their life-history.

‘‘In the urodela the distribution may readily be reduced to the
following type: Upon the body, three lines, a /ateral continuous or
not continuous with an occipital group, though not continuous with the
orbital lines; a ventral line extending from under the arms in the pec-
toral region to near the hind legs; a dorsal line somewhat closely con-
nected with the lateral at its cephalic end and seldom extending as far
as the level of the vent. Upon the head, a series extending from be-
hind the eye, above and below it to the snout, the swpra- and infra-
orbital lines; a line upon the lower lip, the ova/, connected with the in-
fra-orbital by the angular ; a line from the angle of the mouth to the
lateral corner of the head and there meeting a diverging line upon the
ventral side of the head, and, when this is sufficiently developed, a
line or trend of organs upon the side of the head; these the jugular,
gular and postorbital lines of the descriptions and figures.

‘*Comparison with other Ichthyopsida may not be of much value ;
however, the distribution approaches most nearly that in the Dipnoans,
then in Elasmobranchs ; among the latter Chlamydoselachus, apparently,
in the greater extent of the gular line, shows most resemblance to the
Amphibia.

‘*The significance of the arrangement into groups is apparent
when the system is examined in the larva at different periods of devel-
opment. Evidently, as has already been maintained by Malbranc,
each group sprang from a single organ by repeated fission in the same
plane. His figures and my own observations clearly show that such is
the case, as illustrated by Fig. 45. Exactly how this takes place, how-
ever, is unknown. Whether the sensory cells may arise from the sup-
porting cells, or from sensory cells alone, and supported from support-
ing cells or from ordinary epidermal cells, yet awaits solution.

‘* Malbranc called attention to the often recurring arrangement of
groups upon two coordinates perpendicular to each other, or nearly so
(as in the gular line), pointing out the physical advantage in such an
arrangement in perceiving the direction and strength of a vibration in
the water, should such be their function. In Ichthyopsida, in which the
sense organs are deeply sunken in canals, the pores often become many
times divided. In Ama, Allis found that the primitive pores divide
quite regularly in a certain plane for a number of times; these second-
ary pores again often divide ina plane at an angle tothe first, generally
a right angle or nearly so, reminding us of the groups in Amphibia.
In forms, then, in which the sense organs are confined in canals, this

xii JOURNAL OF COMPARATIVE NEUROLOGY.

division of the pores would seem to represent a potential division of the
sense organs, which in forms in which the sense organs are freely situ-
ated, as in Amphibia, can be actual.

“« Attention is called to the necessity, imposed by the life habits
of certain urodeles, ¢. g., Diemyctylus, for the neuromasts to live over
a period of terrestrial existence, which is accomplished by the protec-
tion of the organs by a growth of epidermal cells. Doubtless this is
also true for many other forms of semi-aquatic habits of life, e. ¢.,
Desmognathus. In certain other urodela, e. g., Salamandra, and | be-
believe Plethodon (if they exist at any time), the system perishes entire-
ly in the adult. ‘This is also the case apparently in all the Anura,
though in Aana it persists until after both legs and arms are well devel-
oped and the tail has begun to be absorbed. ‘There would seem, then,
to be something other than an aquatic existence necessary for the main-
tainance of the neuromasts, since Rana catesbiana is more purely aquat-
ic than several of the Salamanders in which the system persists. Of

the mode of final disappearance nothing is known.”
C.J

Brains of Sauropsida.'

The large number of carefully prepared descriptive papers now
issuing from the Cornell University laboratory of neurological research
is an occasion of congratulation not only to the directors of this labor-
atory but to morphologists in general. It is everywhere recognized
that the greatest obstacle now in the way of the best morphological
work is the lack of sufficiently full knowledge of the exact anatomical
structure of the types under investigation.

Studies like the one now under consideration with their detailed
descriptions and full illustration should do much to check the prevalent
tendency to morphological speculation by supplying such a basis of
exact knowledge as will render possible the more satisfactory determi-
nation of morphological fact.

Mrs. Gage has chosen for study the soft-shelled turtle and the
sparrow, not because they represent generalized types of Sauropsida,
but on the contrary because they represent extremes of specialization
of the two great divisions of this group. ‘This is based on an apprecia-
tion of the importance of comparing through all stages of development

1GAGE, SUSANNA PHELPS. Comparative Morphology of the Brain of the
Soft -Shelled Turtle (Amyda mutica) and the English Sparrow (Passer domes-
tica). Trans, Am. Microscopical Soc., XVII. 1896.

Literary Notices. Xili

widely different forms of brains in eadee to gain from exaggerated form
and specialized function more light upon the truths of morphology and
evolution, a principle which might profitably be employed more often
than has been customary.

The nature of the paper is such as hardly to admit of adequate
summary. Coen

Trophic Nervyes.'

1. The functional influence of a nerve cell on an adjacent cell is
always of a trophic nature, either catabolic or destructive, with aug-
mentation of tonus [contraction], or anabolic, restorative with diminu-
tion of tonus [relaxation].

2. The section of a nerve, however carefully executed, always
provokes in that nerve an irritative process which is feeble, it is true,
but of long duration.

3. This irritation of degenerescence, due to the section, evokes
variable consequences varying with the functional nature of the nerve.
If the nerve conducts catabolic impulses, it produces in the cell with
which it is in contact destructive phenomena, long continued and Bet
manent; the cell atrophies.

4. If on the contrary the cell transmits anabolic impulses [inhib-
itory nerves, dilators], it produces in the cell with which it is in contact
feeble but repeated and permanent plastic processes, which cause cellu-
lar hyperplasia with karyomitosis. In this case too there is little increase
of function.

5. If the nerve sectioned contains both anabolic and catabolic
fibres, we find both processes side by side.

6. ‘The existence of trophic nerves in the sense just indicated can
no longer be reasonably denied.

— Revue Neurologique.
Ampullo-oculo-motor Connections.’

The anatomical relations between the vestibular and the oculo-
motor nerves so far as known are indicated in the accompanying dia-
gram which we copy from Dr. Bonnier’s paper. ‘The diagram shows
the direct connections between Deiter’s nidus and the internal nidus on
the one hand and the abducens nidus on the other hand ; also the indi-
rect connection between the former and the latter through the superior

1 WINKLER. Les nerfs trophiques. Vandre medicale, 2 May, 1895.

? BONNIER, PIERRE. Rapports entre l’appareil ampullaire de l’oreille interne
et les centres oculo-moteurs. Rev. Meurol., III, 23, 15 Dec., 1895.

xiv JouRNAL OF COMPARATIVE NEUROLOGY.

olive. It shows further the tract of Duval and Laborde which puts
into direct connection the abducens of one side and the nidus of origin
of the fibres of adduction [oculo-motor fibres] of the opposite side,
thus providing the mechanism of the conjugate movements of the eye-
balls in the horizontal plane, and also the connection via the dorsal lon-
gitudinal fasciculus between the sixth nidus and the fourth and third.

Accom. distance.
Accom. intensity.

Adduction.

_—— Elevation.

Depression.
———- Lid.

Inferior oblique.

_—-— Superior oblique.

NN. Bechterew.

NV. tnternus.
NV. Deitters.

Abducens.

| Superior olive.

tc a cee VIII nerve.

Now the author seeks to correlate these anatomical facts with the
results of some experimental work and a large series of clinical obser-
vations. De Cyon first called attention to the oculo-motor disturbances
associated with lesions of the labyrinth, a fact with which all experiment-
ers on the labyrinth have been forcibly impressed. The most frequent
phenomenon is nystagmus, though all disturbances may be met for they
are all observed in the clinic.

De Cyon was of the opinion that the directions of the oscillations
of the eyeball were determined by the choice of the canal excited.

Literary Notices. XV

Breuer called attention to the inertia of the eyeball by which on a sud-
den movement of the head the eyeball would be displaced in its orbit,
thus interfering with the precision of the visual judgment of the actual
angular displacement of the head. ‘The nervous connections with the
ampullae are for the purpose of correcting this displacement of the
eyeball by the contraction of the appropriate muscles, the latter being
reflexly excited by the head movement as registered in the vestibular
sense organs. It is movements in the horizontal plane which are chiefly
to be compensated and it is a significant fact that it is the abductors
and the adductors of the eyeball which are in most intimate connection
with the vestibular apparatus.

The view of Mendel that vertigo is an oculo-motor disturbance is
combated ; on the other hand it is regarded as in every case due to an
irritation of the connections of the eighth nerve. No doubt titubation
can produce vertigo, but the reverse is the rule, and the fact that we
see objects oscillating is a sort of reflex titubation of the eyeballs sec-
ondarily induced by reason of the intimate relations existing between
the muscles of the eyeballs and the vestibular connections.

Upon the irritation of the labyrinth the abductor of the same side
and the adductor of the opposite side are excited and the eye quickly
turns toward the side of the irritation; the elasticity of the opposing
muscles returns the eye to its normal position, but more slowly so that
the only disturbance of sensation which results is an apparent rotation
of the visual field in the direction opposite to the latter motion. In
other words objects appear to move toward the side of the irritation.
This is a fact which the author has found to be of the greatest value in
clinical practice. Vertical nystagmus is very rare. The author has
observed two cases of which the origin was purely labyrinthin. The
details of several cases of ocular disturbance occasioned by both laby-
rinthin and bulbar lesions are given and at the close the author con-
cludes: ‘‘Ampullar disturbances can find their symptomology in all kinds
of oculo-motor disturbances, and in the presence of the latter it should
be remembered that after the retina itself it is the labyrinth and par-
ticularly the ampullae which are concerned with oculo-motor functions
as well as with equilibrium. All of the oculo-motor nidi, with the ex-
ception perhaps of that of the oblique, which I have never seen in-
volved, may thus be affected by reflex irradiation issuing from the
ampullar apparatus.”

These results of Bonnier agree also remarkably well with those ob-
tained by Lee in his experiments upon the dog fish (Galeus Canis).

Ce Je He

Xvi JOURNAL OF COMPARATIVE NEUROLOGY.

The Initial Stages of the Degeneration of Nerve Fibres.?

The phenomena attending the degeneration of the nervous tissues
have long been matters of the highest interest to the pathologists, and
especially since the recent studies on the regeneration of nerve fibres
any facts bearing on the histological processes involved in degeneration
have an added interest. Numerous pathologists have described the
changes observed in the structure of the nerve fibre in the various cen-
tral and peripheral neuroses and now Dr. Klippel coGrdinates these
morbid processes and finds that they may be resolved into a single pro-
cess which is essentially the same in all cases.

The first stage in the degeneration of the nerve fibre is apparently
a remarkable hypertrophy of the nerve tube. It is not, however, a true
hypertrophy, but a tumefaction, the first stage of a lesion essentially
destructive. The myelin becomes hyaline and loses in the axial por-
tion next to the axis cylinder the concentric appearance so characteris-
tic of the normal fibre. This portion also becomes granular and stains
more intensely than the normal myelin, though not so dark as the axis
cylinder. The fact that this disintegration of the myelin begins ax-
ially and not peripherally indicates that the morbid process has its ori-
gin in the axis cylinder. And in fact simultaneously with the changes
just described the axis cylinder also exhibits hypertrophy with a pecu-
liar change of form. In transection it appears no longer as a circular
dot in the centre of the sheath but as a greatly enlarged and variously
shaped figure, a rod, a spiral, a circle or a sigmoid. In tracing a fibre
from section to section this alters in form showing that the contour is
flexuous and that the fibre is still in a state of degenerescence. Later,
in the penultimate stage of the process, granular fragmentation occurs
to be followed by the final complete resorption.

The degenerative process of the nerve fibre may then be divided
into three stages, the swelling and deformation of the axis cylinder with
the figures just mentioned, the granular disintegration and fragmenta-
tion of the axis cylinder together with the liquefaction of the myelin
from the centre toward the periphery, and finally complete resorption.

In diseases like general paralysis the cells of the cornua of the
cord are affected ina manner strictly analogous. The study of the
early stages of this process is of course attended with the difficulty aris-
ing from the scarcity of material for histological examination taken at
the proper stages of the disease, yet a goodly number of cases are on

1 Kipper, M. Comment débutent les dégénérescences spinales. Arch. de
Neurologie, 2 Serie, I, 1, Jan., 1896.

nn EEE

Literary WNottces. XVii

record, sufficient to show that the process is essentially the same in both
the acute and the chronic degenerative neuroses. ‘The chief difference
between the acute and the chronic cases is that in the initial stages of
the former the tumefaction is more pronounced than in the latter case.

Though the number of these degenerative neuroses is consider-
able, yet the lesion of the nerve fibres involved is essentially the same
for them all. Copy ne

Cortical Olfactory Apparatus.

Mr. G. Elliot-Smith continues his contributions to the morphology
of the smell centre.!_ He notes the simplicity of arrangement of these
centres in non-placental mammals and and the similarity, already in-
sisted on by the reviewer, to that in Sauropsida.

The hippocampus (cornu Ammonis, subiculum and fimbria) forms
in a typical early mammal the dorsal margin of the whole extent of the
fissura choroidea. The ventral margin of the cerebrum in the same
region is formed by the pyriform lobe. The prosencephalic part of the
olfactory bulb is continued caudad as a short peduncle, which almost
immediately divides into the ventro-mesal tuberculum olfactorium and
a lateral pyriform lobe. The tuberculum (our post-rhinal lobe) is de-
scribed as we have described it in the opossum and rodents. ‘‘ These
three parts—hippocampus, pyriform and tuberculum olf.—together
with the precommissural area [our intraventricular lobe] and ‘ septum
lucidum’ constitute the smell centre.” ‘‘ All the rest of the cortex
may be distinguished as ‘ pallium.’ ”

If this distinction is adhered to of course in such cases as Perameles
the pallium becomes greatly reduced. ‘This prepares us for Brill’s as-
sertion that in Sauropsida the ‘‘ pallium” disappears. (Probably in
no other branch of science than neurology is there such a felicity of
whimsicality as that which leads authors to appropriate a word and then
supply it with a modified connotation or alter its application and then
permits them to use a discrepancy of their own creation to discredit
the unfortunate coiner of the word.)

It seems to the writer that if it could be shown that every spot on
the superficial aspect of the cerebrum had been encroached upon by
cells connected with the smell centres it would not be necessary to re-
ject those areas for that reason from the category of ‘‘ cortex” or of
“ pallium.”

Do we not tend to undervalue the plasticity of the brain? In the

' Anat. Anzeiger, XI, 2.

xviii JOURNAL OF COMPARATIVE NEUROLOGY.

tuberculum and intraventricular lobe we have an entirely different his-
tological structure from that of the cortex. In relation with the irregu-
larly grouped polyhedral cells of this region fibres from the bulb ter-
minate. Here we have every morphological and physiological reason
for assuming an infra-cortical station. All analogy requires it and all
the histological appearances are in accord. Processes from these cells
ascend to their cortical fields in the hippocampus. ‘The hippocampus
is just as much a part of the cortex as the temporal lobe!

‘The olfactory peduncle, tuberculum olf. and pyriform lobe are
closely connected with the other hemisphere by means of the anterior
commissure. The precommissural area (intraventr. lobe) is connected
with the other side by a part of the hippocampal commissure, which
Herrick calls ‘ corpus callosum.’ ”

By means of a very strong fibre system situated in the substance
of the tuberc. olfact. and in series with the internal capsule fibres, the
olfactory lobe (possibly the bulb?) is intimately connected with the
lower parts of the nervous system. In Perameles most of them enter
the pes, a few end in the mammillary region.

Mr. Smith, like Debiere, excludes the callosal gyrus from the
“limbic lobe.” Interesting details respecting the fornix fibres are also
given in the same paper.

In the second paper by the same author! we note with gratifica-
tion the tendency toward substantial agreement among different authors
respecting homologies which have given so much trouble. In this re-
spect the study of the Ornithorhynchus and lower marsupials has been
of great help. The long neglected hippocampal commissure seems to
be coming to its own though even Mr. Smith seems not to be aware of
what has been more lately done in its study among Sauropsida.

Smith finds that the cephalic part of the dorsal commissure ends
in the intraventricular lobe but freely accords to it an independent ex-
istence, which is a distinct gain. It is a matter of very subsidiary im-
portance whether this cephalo-dorsal commissure of infra-placentalia is
a homologue of the callosum. ‘The best way to show conclusively that
it is not would be to find it present in a mammal also possessing the
callosum. If its fibres do not pierce the cortical areas at all a strict ho-
mology would perhaps be destroyed. Nevertheless it would be an un-
usual method in nature for fibres to break from one external (median)
aspect of one hemisphere and break into a corresponding aspect of the

1 Notes upon the Morphology of the Cerebrum and its Commissures in the
Vertebrate Series. Anat. Anz., XI, 3.

Literary Notices. XixX

other. Callosal fibres have developed along some pre-existing route of
connection and then attained their present position in obedience to the
usual laws of developmental adjustment. Smith says that the fibres
‘‘probably belong to the lamina infra-neuroporica and supersede the
cephalic part of the fornix commissure whose position they usurp.”
‘‘The corresponding region of the hippocampus [in higher mammals]
disappears and the supracallosal gyrus of Zuckerkandl is all that re-
mains of this region in the Eutherian brain.”

If this suggestion as to the origin of the callosal fibres could in
any way be verified the last serious obscurity in this problem would
seem to be solved.

In a still more recent paper on ‘‘ Jacobson’s Organ and the Olfac-
tory Bulb in Ornithorhynchus”! the same author corrects some very
serious blunders in Dr. Hill’s paper in the Philos. Trans. 1893, whose
specimen had the bulb artificially disconnected and rotated through 45
degrees. The author finds the same olfactory fossa which we have
called attention to in Reptilia and opossum and verifies its relation to
Jacobson’s organ. In Platypus it is much deeper than even in the
black snake but is on the dorso-lateral rather than mesal aspect. A
study of the relations of the part of the olfactory bulb associated with
Jacobson’s organ does not reveal any arrangement different from the
rest of the bulb. It would appear that in all its connections with the
brain the organ of Jacobson exactly resembles the olfactory apparatus
proper and like the latter has its centres in the pyriform lobe and prob-
ably also in the hippocampus. Gs Lane

Fibre Connections of the Olfactory Lobe of Man.’

It will be recalled that recent investigators have shown by a variety
of methods that the connections of the olfactory nerve in the olfactory
lobe are practically the same in all vertebrates, the peripheral nerve
forming a terminal arborization in the glomerule, there to enter into
relations with the protoplasmic process of one or more of the mitral
cells of the olfactory lobe whose axis cylinders effect the cortical con-
nections. In batrachians, reptiles and birds each mitral cell gives off
more than one protoplasmic process and thus is related to more than
one glomerule. No mammal hitherto studied has shown this arrange-
ment, there being but one protoplasmic process to each mitral cell. In

1 Anat. Anz., XI, 6.

2GEHUCHTEN, A. VAN. Le bulbe olfactif de Vhomme, Azbliog. Anatomique,
III, 4, Aug., 1895.

xX JouRNAL OF CoMPARATIVE NEUROLOGY.

all lower vertebrates and in some mammals—cat, rat, mouse, rabbit—
each glomerule receives the protoplasmic process from a single mitral
cell, while in the dog five or six mitral cells effect connections with the
same glomerule, thus putting each olfactory fibre into relation with a
larger number of cortical cells. Examination of the olfactory lobe of
the still-born child with the silver method shows the usual mammalian
type with the following exceptions: (1) the mitral cells are more ir-
regularly arranged than in other mammals, lying often in the glomeru-
lar layer or even among the peripheral nerve fibres; (2) the protoplas-
mic processes of the mitral cells occasionally branch, communicating
with more than one glomerule as in the lower types; (3) most of the
glomerules receive the protoplasmic process of but a single mitral cell,
though sometimes two to four mitral cells are related to the same glom-
erule as in the dog. CAyeHe

The Relation of Sensory and Motor Areas of the Cortex.

The evidence has accumulated in abundance to show that the sep-
aration of motor and sensory areas is arbitrary and untrue to the actual
facts. ‘The ease with which motor disturbance can be demonstrated
may very well account for the pre-eminence given to the location of
motor functions. Munk has shown in a series of brilliant experiments
that even in the visual area the various portions may produce complex
motor responses in the form of codrdinated eye movements. The same
author has shown that the various cortical motor areas are not exclu-
sively so but that approximately the same regions have a sensory func-
tion also. But for our present purpose it is of importance to show that
the same generalization holds good for the human brain. From the
vast material at our disposal it is only necessary to call attention to the
selected cases described by by Dr. C. L. Dana.! The analysis of these
cases shows, as the author states, that it is the power of localization which
is first to be disturbed in case of injury to the cortex, next tactile anzes-
thesia then analgesia, then simple muscular anesthesia and, finally, loss
of temperature sense. Now the higher forms of codrdinated sensations
owe their existence as much to vestiges of earlier sense presentations as
to the actual sense content. ‘This is especially true of localization
and muscular sense. It appears then that one of the most constant of
the results of cerebral injury is the impairment of the vestiges or the
interruption of the paths connecting with the store-house of such im-
pressions. It is a well-known fact that the extent to which vestigial

VJourn. Nerv. and Ment. Dis., Dec., 1894.

Literary Notices. Xxi

impressions are made or memories are accumulated depends on the in-
tensity of the impression or stimulus as well as on the lack of compet-
itive impressions. ‘This may mean that the amount of irradiation of
the stimulus is the factor. At any rate it is easily intelligible that the
vestiges will be first disturbed and that they may in time be renewed,
explaining the frequent return of the power of localization and codérdi-
nation where the tactile sense is not wholly destroyed.

The anatomical structure of the cortex is, so far as can now be gath-
ered, conformable to the necessity imposed by the construction of the
pathological data. Not only is each cell brought into rapport with
many others by the neurodendrites but these connections are in both
rank and file. For every cell that gives rise toa kinesodic fibre or
neuraxon there are many which form its sphere of influence. It is in
accord with the dynamic theory of nervous action to suppose that in
the reaction between the numerous esthesodic cells su/er se and the
other reaction between these cells and the motor initiatory cells is the
immediate occasion of consciousness. Geir

Is the Decorticated Dog Conscious?

It is unfortunate that so few of the students of brain anatomy and
physiology are also acquainted with the first principles of psychology.
The result of this one-sided furnishing is often a deplorable inability to
construe the results of experiment and pathology. If this were all, the
result would have less significance but upon the false conclusions thus
reached a superstructure is often raised, vitiated throughout by the
same fundamental fallacy. In no instance has this lack of psychologic-
al insight been more evident than in the various attempts to explain the
results of total or maximal extirpation of the hemispheres. Every one
will, of course, think at once of the celebrated instance of nearly com-
plete removal of the hemispheres by Goltz and the subsequent reports
by that author and Dr. Edinger. After eighteen and a half months it
would seem that the immediate results of the operation could safely be
considered as eliminated and the results, excluding degeneration phe-
nomena, might be taken as those normal to the brain minus the hem-
ispheres. Even so, the purely physiological questions are by no means
as simple as might be supposed from current discussions. For one
thing, the great inhibitory influence of the cerebral hemispheres being
removed, nothing is more certain than that the infracortical centres
would not operate in the same way that they normally do in the unin-
jured brain. Again, the effect of the concentration of stimuli intended
for the great terminal projection system upon one of a lower order

Xxii JOURNAL OF COMPARATIVE NEUROLOGY.

could hardly fail to greatly alter the reaction. In spite of these sources
of error it is not our desire to intimate that, on the whole, the activities
of the decorticated dog are not fairly indicative of the functions of the
infracortical centres. Strong irritation of the skin caused the animal
to growl and bite, he could be awaked from natural sleep by loud
noises, the taste of food awakened the impulse to feed, etc. But when
an author seriously claims that these facts prove that ‘‘we have un-
doubted manifestations of the presence of every variety of sensation,
tactile, muscular sense, sense of pain, vision, hearing, taste, and finally
the visceral sensations of hunger and of thirst,’’! he betrays a lack of
psychological discrimination and begs the real question. Here, as so
generally, the content of sense is put for sensation and then the conclu-
sion is reached that sensation is produced in the infracortical centres.
Now it would be just as legitimate to decide that because certain pro-
cesses of a nervous character and essential to vision are carried on in
the eye therefore the eye is the seat of visual sensation. ‘There is no
manner of doubt that all the preliminaries to vision including a large
number of coérdinating reflexes are all provided for in the infracortical
centres. It is equally certain that there is a provision for reflexes of a
higher order—such as grow out of the relations of different senses
inter se. All that is reported in the case of the decorticated dog may
well belong in the categories of infraconscious codrdination. It must
be remembered that the consciousness of a sensation is probably never
attained until there has been a kinesodic response to it and it is not un-
likely that it is the reflected current rather than the direct one which
enters consciousness. It is in this way that the storage of vestiges in
the cortex may be explained in such cases where the original stimulus
never reached consciousness. It is absolutely necessary that the line
between physiology and psychology should coincide with that which
separates the conscious from the unconscious or that the distinction be
abandoned. If sensation is selected as the unit of psychology it is ab-
surd to speak of unconscious sensation. ‘The fact that the dog in the
present instance acts as though conscious of a stimulus is no proof of
such consciousness and all admit that there is a complete absence of all
evidence of reproduced sensation or of reflection. It is true that very
complicated sets of cyclical reflexes are produced but something very
similar might under proper conditions be reproduced upon a corpse.
The fact that the cortical connections are not completed until a very
late period of the ontogeny, which is adduced in support of the idea

1W.H. THompson. Journ. Nervous and Mental Disease, June, 1895.

a a

Literary Notices. XXiil

that the dog is really conscious, in reality looks the other way. The
presence of consciousness for some time after birth would be a great
embarrassment to the economy of the animal. The relation between
consciousness and educability is not denied, but it does not follow that
the reflexes are not capable of education while the sphere of profitable
interference of the conscious is relatively very small.

Gee isis

The Paraphysis.'

This paper is mainly concerned with a summary of other and ear-
lier papers by the same author, with, however, some new observations
and an excellent series of photographs. He reiterates the belief that the
paraphysis is an evagination from the cerebrum and is only secondarily
associated with the diencephalon and that it represents, like the parie-
tal eye, an aborted sense organ. ‘This seems to us an improbable view
and one requiring stronger evidence than that presented by the author’s
photographs. Yet the remarkable constancy with which this structure
appears in the embryos of all vertebrates certainly does indicate that
the paraphysis has now or has had an important part to play in the evo-
lution of the vertebrate brain. Just what this part may be we cannot
by any means regard as satisfactorily determined.

In an earlier work the author described the parietal eye of Anguis
as originating by a constriction of the distal end of the pineal evagina-
tion essentially as described by Spencer and the majority of other in-
vestigators. Béraneck, however, finds that the parietal and pineal
evaginations have distinct origins from the roof of the diencephalon,
and now Francotte comes over to the same ground, the error in the
first case having arisen not from inaccuracy of observation, but from an
anomalous condition in the embryo under under investigation. Photo-
graphs of the normal and the abnormal brains are given. Five em-
bryos taken from the same mother were found all to present the same
anomaly. Whichever view of the origin of the parietal eye may
prove to be correct, this paper will do good service in calling attention
to a source of error and of disagreement in many another controversy
besides this one. It is a significant fact that it was during the same year
in which Francotte’s paper appeared that Prenant published his paper
on accessory parietal eyes in Anguis fragilis, in which he made a sta-

1FRANCOTTE, P. Note sur I’ceil pariétal ’épiphyse, la paraphyse et les plexus
choroides du troiséme ventricule. Aull. 7 Acad. Royale de Belgique, 3 Series,
XXVII, 1894.

XXiVv JOURNAL OF COMPARATIVE NEUROLOGY.

tistical study of the variation of these organs and got some surprising
results. Cf. Vol. V. of this Journal, p. xv.

Cig ae
A New Journal.

The first number of the ‘‘ Rrvista di Patologia nervose e mentale”’
appears with the new year issuing from the Clinic of Psychiatry of Flor-
ence. ‘The directors are Dr. E. Tanzi, associated with A. Tamburini
(Reggio Emilia) and E. Morselli (Genoa); the editors are E. Belmondo
and E. Lugaro, together with an able board of colloborators. We are
promised in the prospectus monthly issues making in the aggregate
about 500 pages per year. The field to be cultivated is that of an
“Italian Centra/blatt,” and, judging from the two numbers which have
thus far reached us, the labors of the editors are being wisely and fruit-
fully expended. The review department is well sustained. We append
notices of a few of the brief original articles.

Structure of the Cytoplasm of the Nerve Cell.!

Nissl’s method of differential staining after alcohol hardening,
which has given such an impulse to recent cytological work, is made
the basis of an investigation of the relative functional value of the
chromatic and the achromatic elements of the general protoplasm of
the nerve cells. Dr. Lugaro comes to the conclusion that the achro-
matic substance is the physiologically active medium, while the chro-
matic elements are simply passive. The achromatic part is composed
of a filar mass in the sense of Flemming, while the chromatic part
which alone is stained by the method of Nissl represents an interfilar
mass, and therefore the method of Nissl is absolutely negative regard-
ing the real structure of the nerve cell.

This conclusion is based on the mode of development of the chro-
matic masses, their distribution in the adult cell and their relative abun-
dance in the various processes. The fact that the chromatic substance is
absent in the smallest ramifications of the nerve fibres, and is present in
greater quantity and in larger masses in the larger processes of the cell
and particularly in the cell body itself is regarded as evidence that it
is composed either of nutritive material or of products of dissimila-
tion. The smaller dendritic termini having a greater surface in pro-
portion to their mass do not require any special nutritive mechanism.

' LuGARO, E. Sul valore rispettivo della parte cromatica e della acromatica
nel citoplasma delle cellule neryose. zvista az Patol. nerv. e ment., I, 1, Jan.,
1896.

Literary Notices. XXV

Dr. Lugaro has found in a study which we have noticed elsewhere in
this number that in different functional conditions the variations of the
quantity of the chromatic substance are very slight, while there isa much
more constant relation between the density of the stain and the size of the
cell. But there is another factor influencing the amount of chromatic
substance in the cell, a ‘‘specific factor,” depending on the connections
of the cell or the normal intensity of its discharge. ‘These points are
illustrated by several figures of the nerve cells of both vertebrates and
invertebrates. . Cai:

The Pons Varolii of Man.!

Studies on human fetuses of five to seven months and on the
brains of young children by several of the newer methods.

I. Substantia grisea pontis. These cells occupy the space between
the superficial transverse fibres of the pons and the internal lemniscus,
collecting in the interstices of the fbrae transversae pontis and the fas-
cicles of the pyramidal tract. They are of Golgi’s first type and send
their nervous prolongations into the middle peduncle of both the same
and the opposite side, also into the ventral portion of the raphe. These
fibres are regarded as the scandent fibres of the cerebellar cortex,
whose terminal arborizations lie in connection with the Purkinje cells.

Il. Collaterals of the pyramidal fibres. These are two kinds, di-
rect and indirect, terminating in physiological contact with the den-
drites of the elements of the substantia grisea pontis.

Ill. Pedunculus medtus cerebelli. ‘The middle peduncles are com-
posed not only of tie ascending fibres from the substantia grisea, but
also of descending fibres from the cells of Purkinje. Part of the latter
cross the raphe to terminate in ramifications among the elements of the
substantia grisea of the opposite side, part effect similar connections on
the same side, others pass via the raphe to the level of the segmentum
pontis of the same or the opposite side. They then pass either as fibrae
arcuatae internae or as ascending fibres of the raphe to participate in
the formation of the fasciculus medianus. Some fibres terminate among
the elements of the substantia reticularis grisea tegmenti pontis. To this
tract the author gives the ponderous name, ‘‘direct tract from the cere-
bellum to the nuclei of the tegmentum pontis.”

IV. Internal bundle of the pes peduncult. ‘The author has estab-
lished a direct and crossed connection between the Rolandic and fron-

1 PusATERI, E. Sulla fine anatomia del ponte di Varolio nell’uomo. Nota
prelim. Rzvzsta di Patol. nerv. e ment., 1, 1, Jan., 1896.

XXVi JOURNAL OF COMPARATIVE NEUROLOGY.

tal opercula of the cerebrum and the cerebellar cortex via the swbstan-
tia grisea pontis. The latter has probably other important connec-
tions as yet unknown.

V. Substantia reticularis grisea tegmentt pontis. ‘The cells of this
region have large protoplasmic processes which in part join the internal
arcuate fibres and in part cross in the raphe to the substantia reticularis
of the opposite side, thus forming a protoplasmic commissure of this
region. ‘The axis cylinders of these cells in part cross the raphe, in
part join the internal arcuate fibres; others, arising nearest the raphe,
pass dorsally to join the fasciculus medianus ; still others go to the /eg-
mentum peduncult. :

VI. Collaterals of the fasciculus longitudinalis postertor. These
pass to the nucleus funicult teretis, the substantia reticularis tegmenti pon-
tis and the nucleus reticularts tegmentt pontis of Bechterew.

The reader will be struck with the substantial identity of many of
these results with those of Cajal upon the brains of the dog, cat and
rodent, as described in Bibliographie Anatomique, Dec., 1894.

ee pas iets

The Influence of the Cerebrum upon the Excretion of Nitrogen.!

The experiments were performed on pigeons. ‘The cerebrum was
removed and after complete recovery the animal was kept fasting for
from four to six days. ‘The loss in weight from day to day and the
amount of nitrogen contained in the urine were compared with the
same data from unoperated specimens under the same conditions. The
decerebrated pigeons lost weight much less rapidly than the normal,
and the amount of nitrogen eliminated was still more conspicuously less
in the case of the decerebrated pigeons. On the other hand, a pigeon
which was observed on the days immediately following the operation
showed a geater loss in weight and in amount of nitrogen excreted than
the normal pigeons.

The author concludes that the cerebral hemispheres, at least in
birds, have a marked influence in regulating the metabolic processes of
the body, acting as trophic centres to stimulate the anabolic processes.

C. Jae

1 BELMONDO, E. Ricerche sperimentali intorno all’influenza del cervello
sul ricambio azotato. Révista di Patol. nerv. e ment., 1, 2, Feb., 1896.

Literary Notices. XXVii

Nerve Termini of the Prostate.!

Dr. Timofeew in continuing his studies on the nerve endings of
the sexual organs finds a peculiar structure in the outer connective tissue
capsule of the prostate, as well as between the muscles and glands of
that organ, and in the adjacent mucosa of the dog and cat.

In the cut we give a diagrammatic reproduction of one of his
figures, taken from termini in the capsule of the prostate of a dog.
The structure consists of two fibres, both medullated and issuing from
the same nerve trunk, one of which is much the larger and enters a
capsule in which it terminates in a clavate or ribbon-like expansion.
The other fibre also enters the capsule and terminates in a mass of fine
varicose fibres which perhaps anastomose with each other, but not with
the first fibre. Both fibres lose the myelinic sheath before entering the
capsule. The cut will explain the relations without further description.

Chyna

Demonolotry of the Nineteenth Century.’

The volume before us is a good specimen of the modern pub-
lishers’ art and in other respects challenges criticism. It is, moreover,
a book destined to create a considerable amount of interest in various
circles. Unlike most recent attempts to discuss this most perplexing
subject it at least claims a degree of preparation on the part of writer

1 TIMOFEEW, D. Ueber eine besondere Art von eingekapselten Nervenen-
digungen in den mannlichen Geslechtsorganen bei Saugetieren. Axat. Anz.,
XI, 2, 22 Aug., 1895.

2 J. L. Nevius, D.D. Demon Possession and Allied Themes. 7. A. Revel
Co., Chicago. $1.50.

XXVili JouRNAL oF CoMPARATIVE NEUROLOGY.

and editor which hardly permit of an @ priort waving of its claims. It
demands a serious hearing, if for no other reason, because it claims to
fairly represent the calm judgment of all but an insignificant minority
of the educated occidental missionaries at present actually living among
the Chinese and other oriental peoples. If this is indeed the case it
may give rise to serious reflection or even to the query whether the re-
action of barbarism on the missionary is not as great as his influence on
the barbarism in the opposite direction.

We admit to a feeling of grave responsibility in dealing with such
a work and, while we feel that scientific truth leaves us no alternative,
it is hoped that the reviewer may be credited with no antagonism to the
cause in the interest of which the volume was sincerely written. Even
more, it is because the reviewer believes that the false views here pro-
mulgated will do great injury to that very cause that he does not feel
justified in holding his hand.

At the outset it is freely granted that the entire honesty and credi- »

bility of the author and his witness is assumed in all that follows. The
author has displayed not only praiseworthy industry but considerable
skill in the gathering of facts and discussing their significance, and
when we are forced to add that he seemed singularly lacking in critical
and scientific discrimination it does not follow that the value of the facts
is invalidated. Indeed the naiveté with which facts inconsistant with
the conclusions are set down is sufficient check in most cases. The
author is beyond the sting of criticism and we pass to a consideration
of the work in detail.

In the first place we may quote the author’s synopsis of the facts
and conclusions reached as he closes the descriptive section of his
book. (P. 143.) It will form a convenient point of departure for our
review of the evidence.

‘¢7,. Certain abnormal physical and mental phenomena such as
have been witnessed in all ages and among all nations and attributed to
possession by demons, are of frequent occurrence in China and other
nations and have been generally referred to the same cause.

‘¢2, The supposed demoniac at the time of possession passes
into an abnormal state, the character of which varies indefinitely, be-
ing marked by depression and melancholy, or vacancy and stupidity
amounting sometimes almost to idiocy, or it may be that he becomes
extatic, or ferocious and malignant.

‘¢3, During transition from the normal to the abnormal state,
the subject is often thrown into paroxysms more or less violent, during

Literary Notices. XX1X

which he sometimes falls on the ground senseless, or foams at the
mouth, presenting symptoms similar to those of epilepsy or hysteria.

‘‘4, The intervals between these attacks vary indefinitely from
hours to months, and during these intervals the physical and mental
condition of the subject may be in every respect normal. ‘The dura-
tion of the abnormal states varies from a few minutes to several days.
The attacks are sometimes mild and sometimes violent. If frequent
and violent the physical health suffers.

‘‘5. During the transition period the subject often retains more
or less of his normal consciousness. ‘The violence of the paroxysms is
increased if the subject struggles against, and endeavors to repress the
abnormal symptoms. When he yields to them the violence of the par-
oxysms abates or ceases altogether.

‘6. When normal consciousness is restored after one of these
attacks the subject is entirely ignorant of everything which has passed
during that state.

“7. The most striking characteristic of these cases is that the
subject evidences another personality and the normal personality for
the time being is partially or wholly dormant.

‘¢3. ‘The new personality presents traits of character utterly dif-
ferent from those which really belong to the subject in his normal state
and this change of character is with rare exceptions in the direction of
moral obliquity and impurity.

‘¢g. Many persons while ‘demon-possessed’ give evidence of
knowledge which cannot be accounted for in ordinary ways. They
often appear to know of the Lord Jesus Christ as a divine Person and
show an aversion to, and fear of Him. ‘They sometimes converse in
foreign languages of which in their normal states they are entirely
ignorant.

“‘to. There are often heard, in connection with ‘demon possess-
ion’ rappings and noises in places where no physical cause for them
can be found; and tables, chairs, crockery and the like are moved
about without, so far as can be observed or discovered, any application
of physical force, exactly as we are told is the case among spiritualists.

‘11. Many cases of ‘demon possession’ have been cured by
prayer to Christ, or in his name, some very readily, some with
great difficulty. So far as we have been able to discover, this meth-
od of cure has not failed in any case, however stubborn and long
continued, in which it has been tried. And in no instance, so far as
appears, has the malady returned if the subject has become a Christian,
and continued to lead a Christian life.”

SOK JOURNAL OF COMPARATIVE NEUROLOGY.

A few words in passing upon this summary. ‘The admission of 1
is significant and is fully borne out by the facts adduced. These so-
called possessions are not in any material way different from phenom-
ena with which modern pathology is dealing every day at home with
no doubt of their pathological character. That they have been gener-
ally referred to devils is as forcible an argument as it would be to ad-
duce the universal belief that scrofula was due to the evil eye in a
modern medical consultation. We might drop the matter right here
and would be content to do so if convinced that all our readers were
familiar with the state of scientific opinion. We have, then, not a pe-
culiar set of phenomena but a familiar set in peculiar setting which
alone warrants its selection for special study. Our author does not hes-
itate to suggest (p. 182) that ‘‘ the unscientific Chinese were, so far as
this subject is concerned, more careful observers of facts, and more
correct in their conclusions than many who have been leaders of public
opinion in our times ;” the direct objective being here modern patholo-
gists. This is a remarkable statement which becomes more remarka-
ble with every illustration of the scientific attainments of the oriental
observer and healer.

The symptomatic complex indicated in the following sections con-
tains nothing novel in any way, but the strange circumstances and the
implicit faith of the barbarians in the supernatural character of the
manifestations very naturally produce a strong impression on the visitor.
The author was chiefly struck by the apparent transformation of the
personality during such attacks, yet he is not entirely ignorant of the
fact that a change of personality is characteristic of well-known nervy-
ous maladies. It is gravely stated that the possessed shows super-
natural powers of speech and gaining information. ‘There is, however,
no case given where such powers are proven. It is true that under the
pressure of the disease the patient may seem to speak with tongues, but
when the evidence can be thoroughly sifted such cases usually find
their true place among familiar facts. A case in point now occurs to
the writer. The wife of a prominent theological professor, herself a
woman of great strength and refinement of character but not well-
versed in the German language, awoke one morning and to her own
great distress and the astonishment of her family was utterly unable to
speak a word of English but made her wants known in German. Her
husband was even less familiar than she had hitherto been with that
language so that she was for the most part unintelligible. The good
Doctor, in narrating the circumstances, stated that she spoke fluently,
but admitted that neither he nor she were in a condition to gauge the

Literary Notices. XXXi

correctness of the language. This cultured lady had never had a mas-
tery of the spoken tongue but suddenly, without apparent cause, lost
the speech of her birth and entire life and seemed to have miraculously
acquired a new faculty. . My friend, as a sensible man, did not seek to
exorcise a demon or even send for a doctor, but employed the expect-
ant method until the curious nervous kink straightened out of itself,
never, so far as known, to reappear. If this circumstance, which is
known to very few, had taken place in an ignorant community, the be-
lief in possession would have been absolute and the sufferer, if not of
unusually well balanced mind, would have been tormented into perma-
nent delusions or worse. Again, in the case of the writer it has hap-
pened while studying language and in a stage where ordinarily the act
of composition was painfully tedious, that, say during an early morn-
ing doze, he seemed suddenly endowed with a gift of tongues and
rolled off sentence after sentence with the greatest ease and apparent
accuracy. The neurological explanation of such phenomena is not
difficult and, if it were, the appeal to demoniac possession would add
but another and more insoluble problem. In one case cited by
the author the subject seemed to be able to describe a distant country
and her power was accounted miraculous, but the more than usually
accurate reporter adds that her descriptions were only correct in the
general outlines and not in detail and that she might have picked up
the facts used from other sources.

If the author had lived in this country during the last twenty years
it is unlikely that he would have considered the resemblance of the
oriental table-tipping performances to those which ran their course here
as evidence in favor of their spiritual nature.

One point requires further notice. The morbid personality is
usually qworse than the normal. Does thisseem remarkable? We think
it is only what should be expected. In the life of every person not ut-
terly depraved there is a constant struggle against what are to him temp-
tations. The even trajectory of normal life is the resultant of conflict-
ing forces of which some are (to the subject) bad or malign. This is
quite apart from any absolute moral system. In neurotics these anti-
monies are doubly strong. When, then, the one set of mental forces
are switched out of circuit the other is likely to be immanent. The
ruling or dominant forces are just the ones to be unhorsed for the rea-
son that they are so largely inhibitory while the other set is chiefly in-
trenched in the elementary physical nature.

Before passing to the evidence collected by the author let us note
something of the setting of the facts.

XXxXii JOURNAL OF COMPARATIVE NEUROLOGY.

‘Tt will be observed that nearly all the incidents related are given
on the testimony not of missionaries, but of native Christians—mostly
native pastors.” (Introduction, p. v.) The native Christians continue
in this belief. (P. vi, and passim.)

‘¢ Antecedently to any knowledge of the New Testament the peo-
ple of North China believed fully in the possession of the minds and
bodies of men by evil spirits.” (P.iv.) The natives at once recog-
nized the identity of the biblical possession with the phenomena about
them.

Our witnesses are, then, filled with a prepossession and it would
never enter their minds to seek any other than the demoniac explana-
tion, this ‘‘ belief being a part of that animism, or spirit worship,
which has existed in China—as in many other countries—from the very
beginning of history or tradition.” (P.iv.) They do not regard the
phenomena of possession and exorcism ‘‘as anything strange or re-
markable.” (P. 35.)

Such are the witnesses that are regarded by the author as ‘‘ more
careful observers and more correct in their deductions” than modern
pathologists. We cannot expect the writer under the limitations neces-
sary to his work to exhibit a familiarity with the recent discoveries in
hypnotism but we must at least concern ourselves with the evident bias
of writer and observers.

Again, a belief in exorcism is shown to be universal. The detailed
account of the exorcists (p. 68-71) is very full and instructive. The be-
lief that these professional mediums, whether Confucionist or Taoist,
have a real power to drive out demons is as implicit as that in the spir-
itual nature of the manifestations. If the universal belief of these
heathen is to be taken as irrefrangible evidence we must also believe in
the supernatural power of as pitiful a set of mountebanks as ever dis-
graced the name of man. We must believe in charms, in amulets and
witchcraft. In other words, the learned author and by implication the
whole body of occidental missionaries wish us to abrogate whatever
of moral progress has been made by civilization and return to the be-
liefs and practices of medieval superstition. Probably the author did
not follow his argument to its legitimate conclusion but there is no logi-
cal stopping place short of that indicated. The exorcists are supposed
to be the special aversion of the spirits and ‘‘ never venture anywhere
without having charms, talismans, and all kinds of abracadabras with
them.” Armed with a black mule’s hoof and a black dog’s blood
these practioners do, nevertheless, succeed in going about to very good
purpose. ‘‘She spends her time going about among the villages in the

Literary Notices. XxXxiii

neighborhood telling fortunes, and healing diseases, and in this way
makes a good deal of money” (p. 37). The phenomena attending
séances are exactly such as those with which we are too well acqainted
here. ‘‘ Tables are turned, chairs are rattled, and a general noise of
smashing is heard.” Even Slade and his slate have their counterparts,
‘*the pencil moving of its own accord” (p. 69). The effect of the
mysterious is indubitable. We all recall that no less a person than Pro-
fessor Zéllner was mystified by Slade and induced to commit himself
to absurdities which appear in high relief since the fraud was con-
fessed. That the oriental exorcism is associated with vulgar conjury
and legerdermain is evident throughout these pages and the skill of
oriental jugglers is almost past belief. That, on the other hand, there
is a certain amount of honest belief in the powers of spirit on the part
of the profession is also evident. A large class of semi-professional
healers occupies the same place as the ‘‘ Christian healers” and ‘‘ faith
healers”? of our own locality. Almost while these lines are being
penned anew Man-Christ is touching and prescribing for all manner
of diseases and as many as are touched are made whole. Even hand-
kerchiefs acquire curative power by being blessed by this ignorant pea-
sant. A thriving trade is being driven in counterfeit blessings and ad-
vanced positions in the line at his door have sold for seven dollars.
But it is not necessary to seek isolated cases like that of Francis Schlatter
when any patent medicine circular will reveal a long roll of clerical at-
testations to absurdities too patent to deceive a healthy child. The
love of, and belief in the marvelous is too thoroughly ingrained to yield
easily to judgment or authority.

Prominent among the facts forming the background of these ap-
pearances is the evidence of neurotic predispositions in the subjects
described.

One curious fact familiar to all physicians seems to mystify the
author, i. e., that neurotic individuals are generally the reverse of
feeble in appearance. They generally look younger than others of the
same age and seem quite well to the untrained observer. Indeed it is
one of the special inconveniences of nervous disease that it is hard for
his friends to refer the irritable and distracted moods of the sufferer
to a diseased condition. He gets credit for pure malignity where he
perhaps deserves only profound sympathy, he himself frequently taking
the same view.

So much for the background, but we must notice that the author
is at great pains to insist that there is no conceivable bias in favor of
the demon theory and the resulting practice of exorcism on the side

XXXiV JOURNAL OF COMPARATIVE NEUROLOGY.

of the missionary. In fact, we are told that they are at first skeptical.
How has it escaped the writer that the missionary is under the strong-
est of all inducements to accept the current interpretation? It is, how-
ever, a common experience that one shold be unconscious of the most
powerful motives influencing his belief and we need not impugn the
honesty of such an one in insisting that this motive is patent to every
outside observer. ‘The exorcism of the natives is an integral part of
their religion and is adopted by all sects alike. When Christianity en-
ters the field it must at once compete with these sects in this most prac-
tical matter. Since the function of religion is to control the spirit of
evil, that must be the best religion which most successfully combats
these manifestations of satanic power. ‘The author expresses surprise
that the natives eagerly seize upon the accounts of New Testament pos-
session and need no suggestion from the missionary to turn them to prac-
tical account. The result is what one would expect. Grant, as we must,
that the native doctors are often successful with their burning pills on
the nerve plexus at the roots of the nails, and that the native conjurers
are also frequently able to banish the disease by their incantations, it
-would be expected that the strange message from a land beyond the
realm of dreams should create the conditions for deliverance, nor is it
astonishing that the complete change in mental attitude and the
saner methods of life involved in embracing Christianity should cause,
in many cases, a permanent cure. Even a much less significant change
is often sufficient in practice. ‘‘ The number of those who for this
cause have become Christians is very great.” (P. 51.) The mission-
aries must be much less or more than human if they are uninfluenced
at least unconsciously by this unexpected and powerful means to reach
the otherwise inaccessible heathen. Who shall determine whether this
is not a providential opening? Be this as it may, it would seem un-
necessary to degrade occidental humanity to the same depths of super-
stition and we cannot applaud the attempt.

Fifteen cases are presented from China and we must give up our
plan of analysing them and do so the more willingly that they present
nothing novel or especially pertinent not already noticed. In the spirit-
ualistic career the fortune of the experimenters often mysteriously dis-
appears. ‘The afflicted is incidentally shown to have been a gambler
and profligate, etc. The author explicitly denies that there is any ten-
dency to epidemics but there is evidence, even in the few cases given,
of contagion, i. e. that the influence of others is felt not only in pro-
ducing but in determining the form of the attack (p. 37). The rhyth-
mical form of expression in such cases is as old as history and the author

—— ee ee eee eee

Literary Notices. XXXV

himself notices the resemblance of the utterances of these modern
pythonesses to ‘‘ the meaningless chants heard in Buddhist temples.”
He may not have known of the frequency with which such facility of
versification appears in the exalted states of mania. It will even be
recalled that the habit discoverable in Shakespeare’s characters of drop-
ping into mongrel rhymes at the critical moments has been seriously
defended on the ground that it is acommon tendency of overwrought
minds to spend and distract themselves in poetical expression.

With the second or theoretical part of the book it is difficult to
speak patiently, perhaps unnecessary to speak at all. We are told that
the distinguishing marks of demoniac possession are alterations in per-
sonality. We can form only a vague guess as to what is meant by per-
sonality, but, whatever it is, it remains certain that the vast majority of
the insane would by this law be regarded as possessed. By a simple
application of this conclusion it would appear that dements with morbid
changes in the cortex (as easily detected by the microscopist as small
pox pustules in the skin) should be treated as possessed and cured by
exorcism.

Cases are now well known in which an insane person has two dif-
ferent states or ‘‘ personalities” in one of which he has one set of men-
tal and moral attributes, and in the other, along with certain obscure
but measureable changes in circulation and other physiological func-
tions, displays an entirely different set of mental and moral peculiarities.
In one case he is intelligent and speaks fluently—is crafty and excita-
ble, while in the other he is stupid and speaks a different language.
Nor are we wholly at a loss as to the physical cause of this double man-
ifestation. We find, perhaps, that he is left-handed in the second state
but right-handed in the first. We learn that he was left-handed in his boy-
hood in Wales but learned English and the use of the right hand later,
recelving an education in English. With abundant evidence now at
hand that only one side of the brain is concerned with speech, and that
the side corresponding to the educated hand, we have a right to sug-
gest that both halves of this man’s brain have been modified, the one
in the Welsh or left-handed, the other in the English, right-handed
way. We cannot follow this line further, but it suggests a reasonable
ground for the most difficult phenomena of hypnotism. ‘The author’s
distinction between the pathological and psychical theory is arbitrary.
We think a proper appreciation of the dignity and sphere of the soul
would make one glad to see in the driveling lunacy of the class of phe-
nomena here discussed matters for the alienist rather than the theolo-
gian. It was a very true word in the author’s preface: . ‘‘ Some of the

XXXVi JoURNAL OF COMPARATIVE NEUROLOGY.

readers of these pages will in all probability be disappointed in finding
the characters and doings of spirits much less interesting and credita-
ble than they are represented in the familiar writings of Milton and
Dante.” This in itself would be sufficient refutation of the claim to
most candid readers, but no explanation is vouchsafed.

We ought perhaps to accept the Chinese idea that the demons are
simply the souls of the departed who have not been so fortunate as to
appear in the imperial edict deifying them off-hand.

Of the question as to the relation of the described phenomena
with those of New Testament times we say nothing, though it forms a
large element in the book. But we have done. ‘That the views pre-
sented should be accepted by scientific men is impossible; that they
should gain acceptance in the circle of religious enterprise and educa-
tion would be very unfortunate as it would tend to perpetuate and
‘widen a very unnecessary breach where the fullest harmony and sym-
pathy is important. Gs ire

The Growth of the Brain.!

The present volume is a very worthy addition to the Contempo-
rary Science Series, for in its 19 chapters containing 368 pages, there
is a clear, concise, and very readable statement of the most interesting
facts regarding the growth of the brain.

The author gives in his first chapter an introduction to the study
of growth and sums up the laws which seem to govern it. The grad-
ual increase of the weight of the human body is represented by means
of diagrams, the comparison between the male and female being well
brought out. The next chapter gives with greater detail the relative
increase of different parts of the body, showing the proportion between
weight-increase and increase of stature. In the fourth chapter the
weight of the brain and spinal cord are treated. The point is clearly
made that in taking brain weights other things than nerve cells are
often weighed, as for instance the membranes, pia and dura, the blood
vessels and cavities with their fluid contents; therefore there is bound
to be a certain discrepancy in the weights made by different observers
if the same methods of weighing are not followed. This the author
claims has not been done, and much of ‘the material now at hand is
consequently of little value in making deductions. In trying to arrive

1The Growth of the Brain, by HENry HERBERT DONALDSON, Professor of
Neurology in the University of Chicago. Imported by Charles Scribner's Sons,
New York, $1.25.

Literary Notices. XXXVI

at general conclusions Professor Donaldson believes in grouping the
statistics, for ‘‘ age, stature, sex, bodily weight and race” are all mod-
ifying circumstances. He concludes that there is a marked constancy
in the percentage values. of the subdivisions of the encephalon of all
ages, all statures, and both sexes.

Thus after maturity the male encephalon and all its parts are lar-
ger than the female. With increasing age there is a decrease of the
weight of the encephalon and all its parts, and for the same age and
sex decrease in bodily weight is accompanied by by a decrease in
weight of the encephalon as a whole and in all its subdivisions. In
this respect the two sexes are similar.

In chapter V, on Increase of the Brain in Weight and Variations
of the Cranium in Capacity, the suggestive fact is brought out that the
greater part of the growth of the brain takes place before any of the
formal educational processes have begun. In speaking of the weight
of the brain of non-European races, quotations are made from Hunt’s
observations upon weights of the brains of mulattoes and negroes, in
which he shows that the negro brain is uniformly less than the Europ-
ean, and in those mulattoes with a mixture of less than half of white
blood, the result is even below the negro average, while in a mixture of
over half white blood, the average is between that of the negro and of
the white. In the ‘‘ Variations in Brain Weight” the author states that,
while the heaviest brains belong to the European races and the lightest
to the Australians, yet it is quite impossible, even in a condensed ser-
ies, to harmonize intermediate groups with the theory that brain weight
and culture as we measure it, are closely correlated.

In discussing the brain weights of eminent men a number of inter-
esting tables are given, showing that it would appear that greater brain
weights are more frequent among eminent men even when these are
compared with groups of men of ordinary intelligence but of large
stature. The fact is noted however that most of the comparisons have
been made between ‘‘ eminents”
inals,”’

and ‘‘ordinaries” or even ‘‘ crim-
while the brains of reputable and successful and professional
men have not been weighed. ‘The insane present encephala that are
very slightly less than the normal in absolute weight; while the differ-
ence between the sexes is less marked than in the sane.

Chapter VII gives a good summary of the nervous elements accord-
ing to recent modes of interpretation. The next chapter has an inter-
esting outline of the development of the nerve elements, a subject
that would be of value to pedagogues. Some very important and interest-
ing collections of data are brought together in this chapter, the author

xxxviii © JOURNAL OF COMPARATIVE NEUROLOGY.

stating that the enlargement of the nervous system is due, first to the
increase in number of the neuroblasts formed, and secondly to their in-
crease in size. He thinks that in the growth from the child to the
adult the increase in brain weight is due to the development of the
medullary substance about the neuron.

In the chapter upon the ‘‘ Architecture of the Central Nervous
System” at maturity, there are given those anatomical features of the
brain that are familiar to most students of anatomy, but in addition
there are a number of interesting correlations that no mere text-book
of anatomy ever gives.

The chapter upon ‘‘ Changes due to Growth” tells us how little
we know upon this important subject.

Chapter XIII discusses localization of function giving the main well
known facts upon the subject. The ‘‘ Physiology of the Nerve Cell”
and ‘‘ Physiological Rhythm” present some of the results of later psy-
chological work; while the chapter on ‘‘ Fatigue” gives some of the
observations of Hodge and Vas, in which the author is inclined to lay
more stress upon Hodge’s work than upon the experiments of others
that have given different results. In the ‘‘ Education of the Nerv-
ous System” there are a number of sound generalizations.

This book is to be heartily recommended to the student and edu-
cated layman. While it may at times be difficult for the latter to fol-
low all the mathematical details, yet a persistent reading will give him
a broad grasp of many important and useful facts.

SMITH ELY JELLIFFE, M.D.

Recent Studies in the Forebrain of Reptiles.’

The latest number of this series, which comparative neurologists
have learned to prize as much for its appreciative summaries of the
work of others as for the well-digested results of the author’s own pa-
tient studies, is just at hand. Amongrecent writers Dr. Edinger has
the honorable distinction of never slurring over or consciously misrep-
resenting the work of others. We are often obliged to seek from other
sources the evidence of the large share the author’s own work has had
in attaining the results accredited to others. An error is always frankly
admitted and the genial Doctor seems to feel that a personal favor is
conferred by the writer who is fortunate enough to set him right. It is

1 EpINGER, Dr. L. Neue Studien iiber das Vorderhirn der Reptilien. Un-
tersuch. ii. d. vergl, Anat. des Gehirns, 3. Frankfurt, 1896.

Literary Notices. xo ix

little wonder therefore that views so formed and so expressed have great
weight with his compeers.

It will be impossible in the space at our disposal to recapitulate the
abundant material offered by this paper. Edinger corrects the mistake
made in earlier papers of failing to distinguish olfactory centres of the
first and second orders, or (to use his own nomenclature) Azechfeld and
Ammonsrinde. ‘Yhis whole subject has been elaborately discussed by El-
liot-Smith, Meyer and the writer. About ninety series from a wide range
of groups were employed by Dr. Edinger in his study and the variety of
methods was adequate to insure mutual supplementation. The nomen-
clature used is modeled on that of the recent report of the German No-
menclature Commission. ‘Tracts are named as far as possible by com-
pounding their termini. Instead of using the word lobe to apply to cere-
bral regions Edinger seeks to avoid misleading analogies by such terms
as ‘‘ cortex medio-dorsalis.”’ Although the olfactory fossa is mentioned,
we miss any reference to the Jacobson’s organ fibres. In the basal lobe
three parts are distinguished as striatum, mesostriatum, and epistriatum,
terms, however, which may be open to the charge of suggesting pre-
mature homologies.

In the discussion of the histology of the cortex the results are
similar to those of Cajal. ‘The anterior mantle commissure is no longer
as formerly homologized with the callosum but with psalterium fibres
as a ‘‘commtssura pallit anterior.” We regret that the ambiguous terms
anterior and posterior should be given greater currency. It is to be
noted that in some groups the anterior commissure contains mantle
fibres so that the ambiguity is doubled.

The following tracts are identified with the olfactory apparatus:
The radtatio olfactoria. This is the radix lateralis of other writers. To
this term the author objects on the ground that it suggests a homology
with the roots of cranial nerves. ‘The criticism is well-founded but we
are surprised to see the discovery of the true relations attributed to Cajal.
We had supposed that the origin of the radix fibres in the cells of the
bulb had long been recognized. Certain it is that a good haematoxylin
stain reveals this relation as well as the Golgi impregnation. We have
thus demonstrated it in the Amphibia. On the next page the same
tract seems to be formally named ¢ractus bulbo-corticales, though a part
of the fibres end in the cortex of the lobus olfactorius and part in the
corpus epistriatum. Thus does each part rejoice in, not one, but often
two new names from the same source—thanks to the efforts of the Ger-
man Nomenclature Commission. The pero of Wilder, which the au-
thor has hitherto professed himself unable to differentiate, appears as

xl JOURNAL OF COMPARATIVE NEUROLOGY.

the formatio bulbaris which ‘‘ results from the union of the olfactory
nerve fibres with the processes of the ganglion cells.” We have de-
voted so much space to this structure and its relation to the sheath for-
mation and method of termination that it is with some surprise that we
note the meagerness of detail and reserve as to well authenticated
results.

We do not gather exactly what is meant by the lobus olfactorius—
in figure 5, it would seem to be the pes bulbi, but the description seems
to make it plain that the frontal protuberance of the cerebrum forming
the support of the bulb is intended. The ¢ractus cortico-epistriaticus
consists of fibres rising in the lobus near the termini of the radiatio.
From the area olfactoria arises the tractus olfactorius septi which Edinger
identifies as our radix medialis. It terminates in the cortex of the
hippocampal region—‘‘Ammonsrinde.” The term ‘‘ area olfactoria”’ is
applied to an enormous extent and is divided into the medulus occipital,
tuber thenie (pyriform lobe) as well as the post-rhinal lobe, to which it
would seem to directly apply. The various bundles connecting with the
thalamus are all included in the theenia thalami, including ¢vactus olfac-
to-habenularis and tractus cortico-habenularts. It seems to the reviewer
doubtful whether we are at present justified in referring all these fibres,
with no more to do, to the olfactory apparatus.

If we understand correctly, Dr. Edinger accepts the suggestion
that the epistriatum is an invaginated cortical area. It is to be regretted
that some comparisons were not made with the basal lobe of birds as
described by Turner, who made out similar divisions and even found
an invaginated cortex in somewhat similar relations.

We are glad to note that the author has so far modified his earlier
views as to recognize the probable existence of a tract connecting the
optic centres with the cortex, ‘‘ Sehstrahlung aus den Opticuscentren
zur Rinde.”

Thus the earlier position that the cortex of reptiles is wholly given
up to the olfactory function and its associations is somewhat modified
but appears in the following form: ‘‘ Nur lasst sich sicher bestimmen,
dass der grdsste Teil der Reptilienrinde mit dem Riechapparat
Zusammenhangt.”

It is indeed a most creditable achievement to have called attention
to the psychogenetic significance of the preponderating position among
the cortical stations held by those of smell, but we respectfully repeat
our statement, made on several earlier occasions, that it is not correct
to attribute an exclusively osmatic tone to the cerebral activities of the
Sauropsida or even the Ichthyopsida. ‘The vast complexity of cortical

Literary Notices. xli

histology providing, as Edinger himself recognizes, for wonderfully com-
plicated codrdinations, even did we not know of visual tracts to the
cortex, would suggest a greater diversity of function. We fail to un-
derstand why a connection between the homologue of the geniculatum
and the cortex is overlooked.

The present work is well adapted to serve as a point of departure
for all subsequent comparative studies of the cerebrum.

BET 1k

Modifications of Nerve Cells in Different Functional States.?

A brief historical introduction serves to throw into strong relief
the utter disagreement existing between the results of almost all of the
investigators who have thus far studied this question. The classical
experiments of Vas upon the cervical sympathetic ganglia were re-
peated in 1894 by Gustav Mann (cf. the review in Vol. V of this Jour-
nal, p. xxxil) and again by Lugaro in the paper before us. The latter
author feels that he has removed many of the contradictions of the
previous investigators and explained the others. He calls attention to
the fact that the so-called resting cells of other authors are by no means
such but that to the fatigue of normal functioning before death
must be added the intense discharge accompanying their excision as well
as those changes occasioned by the action of the fixing reagent between
the time of immersion and the time of cellular death. Another source
of error is the subjective one arising from the difficulty of estimating
the relative sizes of the normal and fatigued cells when the sizes of both
sets vary within wide limits. The former difficulty was met by kill-
ing in various ways, particularly by comparing cells fixed by rapid ex-
cision and treatment with the fixing fluid with those taken several hours
after death from an animal killed by rapid chloroforming ; the latter diffi-
culty, by carefully counting all of the cells from many average fields
from each of the two sets of preparations. In each ganglion the long-
est diameter of 1000 elements was measured.

The results of these observations are presented in the form of a
series of curves. Cells of ganglia taken from the body five hours after
death when compared with normal cells (taken from the body by vivi-
section) show a decrease in size 4.95%. Elements electrically excited
for a time which does not exceed a half hour show an increase in size
as compared with the normal. ‘This increase is at the maximum of

1 Lucaro, E. Sulle Modificazioni delle Cellule nervose nei diversi Stati
funzionali. Lo Sperimentale, XLIX, 2, Aug., 1895.

xlii JOURNAL OF COMPARATIVE NEUROLOGY.

6.69% with an excitation of five minutes. If the excitation is contin-
ued longer than a half hour there is a strong diminution in size of the
cell. After excitation of one hour the diminution is .84%, after three
hours 11.5%, after six hours 16.53%.

Synthetic curves based upon the measurements show that the size
of the cell rapidly increases during moderate activity, but under pro-
longed stimulation diminishes far below the normal ; that the size of the
nucleus follows the same law but to a less extent and less abruptly ;
that the size of the nucleolus increases more rapidly than the size of
the cell and that it diminishes under prolonged excitement much more
slowly. The author concludes that the size of the cell is acted upon
by two tendencies, one positive, activity, the other negative, fatigue.
Letting d represent the dimension of a cell, 7 the normal (average) size,
a the alteration due to activity, and / that due to fatigue, d will vary as
expressed in the following equation :

d=—n+n(a-f).

The tardy alterations in the nucleus are regarded as consecutive
to those in the cytoplasm. The nuclei, contrary to Hodge and Mann,
do not wrinkle.

The experiments are thus summarized :

1. The activity of the nerve cell is accompanied by a state of
turgescence in the protoplasm of the cellular body.

2. Fatigue causes a progressive diminution in the size of the cell-
ular body.

3. In moderate degrees of activity, while the cytoplasm swells,
the nucleus suffers no modification of volume.

4. When the activity is continuous and of long duration, the nu-
cleus suffers modifications analogous to these of the cellular body, but
less intense and slower.

5. The quantity of chromatic substance in the cellular body va-
ries always as an individual character in proportion to the size of the
cell. Nevertheless it is probable that the first phases of cellular activ-
ity occasion a slight increase in its amount, the last phases accompanying
fatigue, a diminution and a more diffuse distribution.

6. The activity of the cell occasions in the nucleolus an increase
in volume which gradually yields to the reducing action of fatigue.

Following these experiments are some very interesting theoretical
observations in which attention is called to the fact that if we extend
the knowledge acquired of the changes in form of the body of the cell
to include the cellular processes also, assuming that the processes elon-

Literary Notices. xiii

gate during functional activity and shorten during fatigue, we have
taken a long step in the direction of a knowledge of the physical basis
of the corresponding emotions, as well as of the physiological facts as-
sociated with exercise and fatigue. CHE

The American Lobster.'

Six years ago Dr. F. H. Herrick was invited by the United States
Commissioner of Fisheries to prepare a monograph on the Biology of
the American Lobster. <A systematic investigation was begun and in
this final paper, which has been awaited with considerable eagerness by
the biologists, we have a summary not only of the author’s own re-
searches, but of practically all that is known concerning the life history
of this species. The work makes 252 pages quarto and is accompan-
ied by 64 full page plates, many of them colored to life, illustrating
very fully the development and gross anatomy. ‘The details of the fine
histology are not entered into except in a few cases.

The practical and scientific value of the work are both very great.
It is not common to find both of these features so well represented in
a single monograph.

. One of the points of greatest practical importance, bearing on the
problems of the artificial culture of lobsters, is the chapter on The
History of the Larval and Early Adolescent Periods. The account of
the Embryology of the Lobster is more meager than we should have
expected from the fact that the author has devoted so much attention
to this subject and has already published several short papers. He
makes no attempt to give a detailed account of the embryonic history,
but a few notes merely on the early phases of development.

From our standpoint the topics of especial interest centre about
the descriptions of the habits and organs of sense of the lobster. The
breeding habits, habits of migration and feeding and the like are quite
fully detailed. In its native haunts it shows considerable agility in
avoiding its enemies and cunning in the capture of its prey. The
senses of sight and and hearing are probably far from acute, but it pos-
sesses a keen sense of touch and of smell and probably also a sense of
taste. It is also quite sensitive to changes of temperature, this being
the factor in the environment which is in the main responsible for the
periodic migrations of the lobster.

Experiments made with various stimuli, such as electricity, heat,
weak acetic acid, ammonia gas and clam juice, led to the conclusion that

1HERRICK, FRANCIS HOBART. The American Lobster: A Study of its
Habits and Development. Auzlletin U. S. Fish Commission, 1895.

xliv JOURNAL OF COMPARATIVE NEUROLOGY.

all or nearly all of the appendages react strongly to chemical stimuli and
in many cases the surface of the body is capable of receiving and re-
sponding to stimuli of various kinds. In some places the skin of the
lobster with its shelly covering seems quite as sensitive as that of the
frog. ‘The organs by which the stimuli are conducted through the chit-
inous shell must be either the hair pores or the glandular ducts. The
author decides in favor of the latter.
Cah ie
Pain in the Pectoral Region Sympathetically Accompanying Irritation
of the Forearm '

The patient, a fireman, developed very peculiar symptoms, prob-
ably as the result of a fall and injury of the back and elbow. Con-
stant though unequal pain is felt in the right shoulder on the right side
of the back at the level of the seventh dorsal spine. On the right side
of the chest, in front, there is an area bounded laterally by a vertical
line from the axilla to the sixth rib and mesially by a line laterad of the
right nipple. The pains felt here have a burning or tearing character.
Beneath the right nipple is another painful spot which only announces
itself after exertion, as rapid walking or turning in bed. ‘The posterior
aspect of the right arm also is subject to pains, generally induced by
pressure over the radio-humeral articulation. The area does not in-
clude the fingers but extends upon the dorson of the hand. Bending
the elbow causes severe pain, as does movement of the wrist, though
there is no swelling of the joints.

A touch on this arm area is felt in the pectoral area, as well as in
the arm; firm pressure over any part of the arm area, except the pain
centre over the joint, causes severe tearing pain in the pectoral area. For
years the patient had been in the habit of sweating profusely with the
right side only though when at work all parts perspire alike. A fall a
week or so before the symptoms appeared injured the elbow and back
and there seems to have been a blow of a less violent sort on the chest.
The author thinks this a case of sympathetic neuralgia but there is dif-
ficulty in discovering the nervous connections necessary to satisfy the
hppothesis. C.as en,

Corrigendum.

On page ix of this issue in the review of Professor K6lliker’s arti-
cle, line 7 from the bottom of the page, insert after ‘‘ habenulae, ”
‘¢and ends in the ganglion interpedunculare.”

1 Munro, T. K. Brain, IV, 1895.

LITERARY NOTICES.

The Development of the Brain and Sense-Organs in Elasmobranchs.!

This well-prepared paper is somewhat misrepresented by its title,
for it is in reality, in so far as concerns the original portions, a study of
metamerism of the brain and the origin of certain sense organs based
on embryos of Sgualus acanthias. ‘The questions to which this paper
addresses itself are sufficiently ambitious, being such as the following :
(1) What was the primitive condition of the nervous system of verte-
brates? (2) What were the number and nature of the primitive neural
segments entering into the brain? (3) What has been, in general, the
line of modification along which they have been converted into the brain?
(4) What were the early steps in the differentiation of the sense-organs?
This is certainly a program calculated to awaken high expectations and
itis no detraction from the genuine excellence of what is offered to
admit that the materials and their employment are undoubtedly inade-
quate to its fulfilment. The paper does, however, give very useful
summaries of the historical development of those phases of the sub-
jects which are taken up.

The earlier part of the paper is occupied with the problem of
metamerism. ‘The author apparently agrees with McClure in mini-
mizing the segmental value of the cranial nerves because of the uncer-
tainty due to the degenerations of certain branches and even entire
nerves. ‘This may appear inconsequent when he, at the same time,
explains the segmentation of the tube as due to the cranial nerves.
This criticism is not necessarily valid, however, for it may be true that
the segmentation of the brain was originally due to the concentration
of nervous matter adjacent to the point of development of the segmen-
tal nerves and yet this segmentation might persist in an early stage of
animals in which the subsequent development processes had been di-
verted. In other connections, however, the author fails to avail him-
self of this possibility. Professor Locy does not admit that the seg-
mental divisions of the middle germ layer are primitive. He accepts

1 Locy, Wm. A. Contribution to the structure and development of the
vertebrate head. Journ. Morphology, X1, 3, 1895.

xlvi JOURNAL OF COMPARATIVE NEUROLOGY.

the writer’s suggestion that ‘‘if neuromeres once existed in the fore-
brain they would be visible only at an early stage. . . The so-called
fore-brain neuromeres differ from those of the medulla in involving
only dorsal structures.” He also apparently succeeds in resolving the
the discrepancies between Froriep’s account and that of other writers.

Fifteen pages are devoted to original observations on metamerism
in Acanthias and both descriptions and plates are admirably done.
Especial praise should be awarded the plate of photographs of the very
young stages which are particularly valuable, as also the dissections re-
produced in plate XXVIII. The constancy of the phenomena in ex-
tremely early stages in various groups serves to justify the present
writer’s prediction and to furnish a new motive for a re-canvass of the
subject. The suggestion that they are artifacts is satisfactorily disposed
of, though it is less clear that the node-like structure sustains a positive
and constant relation to the definitive structure of the brain. Do they
look backward rather than forward?

This segmentation is said to be independent of mesodermic influ-
ence and, as proof of this, the fact is cited that it precedes the meso-
derm segments. It should be noted, however, that if it be conceded
that the segmentation is not due to direct mechanical influence and so
really has morphological significance, as the author claims, then we
must look for the cause in a state when the head was fully segmented
and mesodermic influence then could readily be appealed to. This the
author would doubtless agree to.

In Sgualus he recognizes as represented in the ontogeny at least
fourteen paired neural segments. ‘The assignment of neuromeres to
the sense organs and nerves is as follows :

I. Olfactory.
ies Optics | Fore-ba
III. Pineal sense organ ?

IV. Oculo-motor. . .
V. Trochlearis. \ Mid-brain,

VI, ‘Anterior’ (cephalic?) root of V. }
VII. Main root of V. |
VIII. No nerve. |
IX. Facialis. L ry: .
X. Auditory. [ Hind (Beata,
XI. Glossopharyngeal. i
XII. |
XIII. | vagus J
XIV.

The segments are serially homologous. In Sgualus the optic vesi-
cles are the first rudiments of sense-organs to appear and originate be-
fore the separation of the fore-brain. Their peculiar form has led to

Literary Notices. xlvii

their being long overlooked. The curious segmental sensory patches
which were described by the author as accessory optic vesicles arise in
in a way similar to that of the eyes. ‘They first make their appearance
when the neural plate is broadly expanded. Four pairs of such organs,
at least, are noted, the cephalic pair forming, as is claimed, the pineal
body. ‘They are embryonic and transitory structures and are thought
to point back to a multiple-eyed pre-vertebrate condition.

A review of the literature upon the pineal seems to the author to
lend force to the suggestion of a multiple-eyed ancestor of vertebrates.
The results ‘‘ go to show that there are two distinct outgrowths of the
thalamencephalon of Petromyzon, Teleosts and Lacertilia.”” The ceph-
alic one is that developed into the pineal eye in front of the epiphysis
in Lacertilia, and corresponds to Hill’s anterior vesicle in teleosts.

In passing, it seems that a halt ought to be called in the unjusti-
fiable introduction of untranslated descriptive terms from the German.
‘¢ Zirbelpolster ” is not an English word and is not a desirable addition.
If a popular term is needed it may be easily translated but it is much
better to substitute a Latin equivalent. Our European friends should
also realize that the scientific world cannot consider an organ properly
named and presented for acceptance until a name has been proposed
conformable to the common nomenclature of the scientific world.

The auditory organ is briefly discussed and its relation to the lat-
eral line system recognized.

The paper supplies many details that have been wanting hitherto
and has several pregnant suggestions, but its chief value is in the com-
pleteness and apparent accuracy of illustration.

CPL. He

The Sensory Physiology of Actinians.!

Recognizing the growing importance of the comparative physiolo-
gy of the nervous system, especially among the lower invertebrates,
Dr. Parker has undertaken a series of experiments on the common ac-
tinian of the Atlantic coast, Metridium marginatum. In taking food,
two kinds of responses are met, ciliary and muscular; only the latter
shows evidence of nervous control, Numerous experiments illustrate
the slight physiological centralization in the nervous functions of these
organisms. Each tentacle acts like an independent organism. ‘The
curious fact is observed that the cilia on the lips reverse their motion

1PARKER, G. H. The Reactions of Metridium to Food and other Sub-
stances, Bul. Museum Comp. Zool., XX1X, 2, March, 1896.

xl viii JOURNAL OF COMPARATIVE NEUROLOGY.

during the act of swallowing. ‘The usual stroke of these cilia is in a
direction away from the mouth, as is shown by the motion of particles
of carmine or other insoluble substance. But when a piece of meat or
a drop of meat juice touches these cilia they reverse their motion after
an appreciable latent interval.

G.. jel

The Histology of the Myelon.!

The ‘* Retssner’s” or ** Dorsal Cells” of the Cord. Many years
since, peculiar cells were noticed in the dorsal portion of the spinal cord
of Petromyzon. Reissner described them in 1860, and, in 1877,
Freud succeeded in tracing their axis cylinders into the dorsal root,
though it has since been shown by Beard that they do not originally
emerge with the sensory fibres and are of a kinesodic nature. Rohon,
in 1885, detected similar cells in the trout and they have since been
noticed in the embryonic stages of other Gnathostomata. According
to Studnicka, however, these cells, though distinguished from adjacent
elements by their great size, are not homologous with the ‘‘ colossal
cells” of the spinal cord of Amphioxus. ‘The latter are median in po-
sition and are sparsely distributed; their axis cylinder passes laterad and
arches ventrad and, after crossing to the opposite side, extends toward
the head. Some of their smaller processes were traced by Koelliker

Horizontal Jongitudinal section of Reissner’s cells from dorsal region
spinal cord of Ammocetes. of spinal cord of Pristiurus.

into the dorsal roots. Respecting these Studnicka suggests that they
may probabiy be regarded as inherited from some invertebrate prede”
cessor. He claims that the ‘‘ medium-sized” cells of Amphioxus cor
respond with the Reissner’s cells of higher forms. ‘These are bipolar,

ISTuDNICKA, F. K, Ein Beitrag zur vergleichenden Histologie und His-
togenese des Riickenmarkes. Sttzd. Aongl. bihm. Gesellsch., 1895.

Literary Notices. xlix

occupying a lateral position with respect to the central canal. One of
the main processes (Studnicka calls them both axis cylinders) passes in
a longitudinal direction, while the other emerges with the dorsal root.
If this identification be correct Reissner’s cells occur throughout life in
Amphioxus, Petromyzon, Protopterus, ‘Triton, and certain teleosts,
while in the selachians and ganoids, as well as some others, they are
embryonic and transient.

In Lophius it will be remembered that they have a very restricted
but specialized occurrence. The form is generally crescentic with the
concavity mesal. One of the processes crosses to the opposite side of
the cord and passes either toward or from the head. ‘The other or
true axis cylinder originally passed directly ectad and innervates the
myotome, though in some cases it associated itself with the dorsal
root. Burckhardt’s ‘‘ Randzellen ” described in Protopterus are found
to occur in Petromyzon also, but they have nothing to do with the
Reissner’s cells. ‘The term selected by Studnicka, ‘‘ Hinterzellen,”
suffers from ambiguity common to the German terms of direction. If
we substitute ‘‘ dorsal cells” there is a possibility of confusion with
cells of the dorsal cord so that the familiar term Reissner’s cells may
still be employed.

In a second paper! the same author describes the expansion of the
canalis centralis found at the caudal extremity of the cord of Amphi-
oxus and the Cyclostomata and differentiates it under the name ‘‘ Sinus
terminalis” from the ‘‘ Sinus sacralis”” of acaudal vertebrates. Such
significance as this ventricle has may be assumed to be in connection
with the equilibrium of the cerebro-spinal fluid.

(Go) Whig Tels

Anatomy of the Cerebrum of Notoryctes. ”

Although based on imperfect material and studied under adverse
conditions, the notes upon the brain of this little-known marsupial will
prove welcome. In respect to the brain at large the small size of the
cerebrum and limited extent of pallium are correlated with the exposure
of a relatively large part of the corpora quadrigemina and a very sim-
ple condition of the cerebellum.

The cerebrum presents an extreme simplicity of structure and
while is has superficial resemblances to Talpa and Dasypus it is yet in

1Ueber die terminale Partie des Riickenmarkes,

2G, ELLIoT-SMITH. The Comparative Anatomy of the Cerebrum of No-
toryctes typhlops. Zyrans. Roy. Soc. Australia, 1895.

] JOURNAL OF COMPARATIVE NEUROLOGY.

morphological plan identical with the apparently dissimilar Macropus.
The mesal olfactory fossa is absent but it does not appear whether this
is correlated with any peculiarity of the Jacobson’s organ.

The pyriform lobe takes an increasing share in the formation of
the lateral part of the hemisphere as the extent of pallium decreases.
The region reaches the height of its development early in ontogeny and
phylogeny, hence its surface always remains smooth. Herrick and
Bawden are criticised for confusing of the hippocampus when they
evidently mean the pyriform but this criticism apparently rests ona
misapprehension. ‘The tuberculum olfactorium is of great size. Hill’s
usage in excluding this body (the post-rhinal lobe) from the rhinenceph-
alon is characterized as ‘‘ ridiculous” —an expression which must be
accepted as applying to the critic’s risibilities alone and which over-
steps as a personal reflection the limits of professional courtesy. The
author evidently meant ‘‘ preposterous” or ‘‘ inconsistent” but this
must depend on the morphological extension involved in the term
rhinencephalon.

Additional illustrations are given presumptively in favor of the
view that the ‘‘ commissura pallii anterior” is not a callosum, but inci-
dentally illustrating the long-questioned fact that there are two dorsal
commissures in marsupials, which, after all, has been that chiefly in
the minds of the writer and others who have sought to enforce the
distinction between the hippocampal and callosal portions of the dorsal
commissure.

The reader may seek the original fora variety of details and
generalizations.

The illustrations are far from successful. (Ory BPs

Romanes on Weismannism. '

This new edition of the ‘‘ Weismannism” is well printed and fur-
nished with an excellent portrait of the author. It is one of the few
really good cheap books which stand in so marked contrast with the ten-
dencies of the time in book making. We have already noticed an earlier
edition, but would again call attention to this discussion of the theories
which Weismann has erected on the basis of his fundamental postulate
of the non-inheritance of acquired, or somatic characters, as assuming
a new importance in the light of the more recently published work of

1 An Examination of Weismannism. By GEORGE JOHN ROMANES. Chicago,
The Open Court Publishing Co., 1896, Price 35 cents.

Literary Notices. li

the same author in which he has discussed the truth of this postulate. 1
The two books should be read together, if one would gain a true view
of Mr. Romanes’ views on these important questions. Caja er:

Germinal Selection. 2

The address delivered by Dr. Weismann before the International
Congress of Zoologists at Leyden, 16 Sept., 1895, is here expanded
and translated. The fundamental difficulty urged against Weismann and
the other so-called neo-Darwinists by their critics is the impossibility of
accounting for many of the adaptations as we find them on the basis of
a theory of natural selection which recognizes only indefinite variabil-
ity. The simultaneous occurrence of the variations necessary to pro-
duce, e. g., a case of mimicry in a butterfly, is hardly credible except
on some hypothesis of definitely directed variability. The hypothesis
of germinal selection assumes that when natural selection acting on
accidental somatic variations in the manner usually described has re-
sulted in a slight increase in the efficiency of the part in the given di-
rection, then the determinants corresponding to that part in the germ-
plasm of the next generation will be more vigorous than the determi-
nants of other parts and in the struggle for food will outstrip them.
Thus that part will in the adult be stronger than it was in the previous
generation, and this result will be cumulative. So the germ is progress-
ively modified in the direction set by utility.

Though very little has yet been published on this specific phase of
the problem, the general question of definitely directed variation is one
to which every thoughtful biologist must have given some attention.
The success of this attempt to explain the mechanism of the process
will rest on the value of Dr. Weismann’s scheme of the hereditary ma-
chinery. And in estimating this we must recognize the purely symbolic
nature of the conceptions used by the author of this scheme, a fact
of which, as he points out, his critics have often failed to take account.

To one who, like the reviewer, is unwilling to admit the absolute
non-transmissibility of somatic characters it is obvious that the argu-
ment for germinal selection cannot be accepted exactly as here out-

lined ; yet the principle may be a true one and is not necessarily incom-
patible with an application of some form of the Lamarkian doctrine as
well. (Sei fouls

1 Darwin and After Darwin. II. Post-Darwinian Questions, Heredity and
Utility. Chicago, The Open Court Publishing Co., 1895.

2 WEISMANN, AuGusT. On Germinal Selection. Chicago, The Open Court
Publishing Co., 1896. Price 25 cents.

lii JOURNAL OF COMPARATIVE NEUROLOGY.

The Psychology of Attention.

This is the third revised edition of the authorized translation pub-
lished by the Open Court Co., Chicago. There is perhaps no writer
who has done more to popularize the idea that a neurological founda-

.tion is essential to the full comprehension of the higher mental activi-
ties than Professor Ribot. Of the value of this standpoint we have no
better proof than the stimulus which has been given to recent research
by Professor Ribot’s own works. Even those who cannot accept all of
their conclusions are ready to acknowledge their indebtedness to them
for many pregnant ideas.

We can summarize the present book no better than in the author’s
own words. ‘‘ Attention depends on emotional states ; emotional states
are reducible to tendencies; tendencies are fundamentally movements
(or arrested movements) and may be conscious or unconscious. Atten-
tion, both spontaneous and voluntary is, accordingly, from its origin on,

bound up in motor conditions.”
Cojo

Studies from the Yale Psychological Laboratory,

Volumes I and III of these studies are on our table. Volume II
has already been noticed. The first volume is concerned mainly with
investigations in reaction time. The most extensive article is the thesis
of Dr. Bliss on ‘‘ Reaction-time and Attention.” Throughout this
series of many hundreds of reactions especial attention was paid to the
subjective state of the reagent. After having demonstrated that per-
fect darkness in the reacting room is in no way preferable to a uniform
illumination, the reagent—in most cases Dr. Bliss himself—sat with
pencil and paper at hand and at the close of each series of experiments
annotated them. In many respects the most valuable part of the pa-
per is the analysis of the reactions in the light of the data of introspec-
tion. This principle, which has been more recently recommended and
practiced at the Paris laboratory, is one of great importance. The
prevailing German tendency to reduce the reacting subject to a mere
automaton, while in many experiments useful, can never give the whole
truth.

Not the least valuable part of the paper by Dr. Bliss is the very
full description of the apparatus and the details of the connections em-
ployed. Indeed this is an important feature of nearly all of the stud-
ies included in these three volumes. From the inauguration of the
Yale laboratory the devising of new apparatus and laboratory conveni-
ences has been given a prominence which puts all other workers under

Literary Notices. liti

obligation, an obligation which the present writer gladly acknowledges,
as he has found many of these contrivances very useful in his own la-
boratory.

The leading article in the third volume is by Dr. C. E. Seashore
on ‘‘ Measurements of Illusions and Hallucinations in Normal Life.”
This is a paper of vital importance to every laboratory psychologist,
for the conclusions reached have an important application to some of
the most fundamental methods of the experimental method. By an
elaborate series of experiments, the details of which must be sought in
the original, Dr. Seashore has shown the truly surprising ease and _viv-
idness with which it is possible to evoke illusions and hallucinations in
every department of sense and that too in experienced psychologists
and under the conditions of rigid control of the laboratory experiment.
The hallucinations here described are evoked mainly in response to
forced expectant attention and it is shown that this is one of the fac-
tors which must be guarded against in all experiments on liminal differ-
ences. Certain experiments on discrimination and many other classes
of laboratory studies will receive cautionary hints from this paper.

The ‘‘ Studies of Fatigue” by John H. Moore take up the effect
of fatigue on binocular estimate of depth, the effect of fatigue on mon-
ocular estimate of depth, the effect of fatigue on the time of monocular
accommodation, and the effect of fatigue on the maxium rate of volun-
tary movement. Several points of practical pedagogical interest are
developed. For instance, several of these experiments on the estima-
tion of depth by means of the muscles of accommodation and con-
vergence emphasize the extreme danger to the eyes of carrying on for
long periods of time such accommodation as must be employed in
copying unfamiliar subjects from the blackboard to the paper or slate, as
is so often done even in the lower grades of our schools. (Coal ini zis

The Embryology of the Medulla of the Rabbit.'

In this paper Dr. Dexter has followed the development of the
medulla of the rabbit in order to make comparisons with that of man
as worked out by His. He finds several differences, some of them
quite unexpected. ‘The tractus solitarius is buried more deeply in the
medulla as development progresses by the migration, as the author sup-
poses, of scattered ectodermal elements lying on the border of the me-
dullary wall and ‘‘ Randschlier,” and not by the formation of a rhom-

'FRANKLIN DEXTER, M.D. A Contribution to the Morphology of the Me-
dulla Oblongata of the Rabbit. Privately printed from the Archiv fiir Anatomie
und Physiologie. Boston, 1896.

liv JOURNAL OF COMPARATIVE NEUROLOGY.

boidal lip as in the human medulla. The rhomboidal lip as described
by His was nowhere developed. ‘The tractus solitarius is not regarded
as wholly homologous with the oval bundle of the cord. The tractus
solitarius is shown to receive fibers from the V, VII-VITL, Re andi
ganglia very much as in the Amphibia Cees

Uranism.!

This extensive work of over 350 pages is devoted to a thorough
exposition of the subject of unisexuality in all of its aspects. Itis a work
of more limited scope than Krafft-Ebing’s famous ‘* Psychopathia”” and
is written from an entirely different standpoint. It resembles that
work, however, in the vast wealth of its historical, statistical and crit-
ical data. It is not our purpose to attempt an abstract of the author’s
conclusions. With many of his positions our readers are already fa-
miliar. We need only add that we are in full accord and sympathy
with his thesis that the misfortune of congenital sexual inversion is in
no sense a justification for any form of sexual immorality. The subject
is confessedly a confusing and perplexing one in all of its phases, but
this point we think Mr. Raffalovich has quite satisfactorily established.
And this is by no means incompatible with the further claim that the sex-
ual invert ought not to be expected to conform in all respects to the
mode of life of those who are normal in this respect. But if it should
prove impossible for him to conform to this norm, it does not follow
that he should not put the same restraint upon himself to which many
another and perfectly normal person must often submit himself.

Ciao

Electricity in Electro-Therapeuties.”

This little book is, as the title indicates, a treatise on electricity,
nor a treatise on electro-therapeutics. ‘The authors have succeeded
for the most part well in their attempt to so present the principles of
electricity that any physician may comprehend them, even though he
may have had no previous technical training. ‘The book is to be com-
mended as just what the practitioner needs to enable him to use intelli-
gently the electrical apparatus with which his office is, or should be,
supplied. Coie ae

>

1Uranisme et Unisexualité. Etude sur différentes manifestations de ]’instinct
sexuale. By MARC ANDKE RAFFALOVICH Bibliothéque de Criminologie.
Lyon, 1896.

Electricity in Electro-therapeutics. By Epwin J. Houston, Ph.D., and
A. E. KENNELLEY, Sc.D. Mew York, The W./. Johnston Co., 1896. Price $1.00.

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