either to the apolar or bipolar variety. It is pos-
sible, however, that many of them, as Wagner,
Robin, &c. maintain, although apparently apo-
lar, are really unipolar or bipolar cells, from
which one or both processes have broken off
during the process of preparing them for ex-
amination. That the bipolar cell exists in
F F 3
438
SYMPATHETIC NERVE.
man and other mammalia, is proved by the
observations of Schroeder van der Kolk in
Fig. 287.
A. Spinal ganglion from the Kay. (40 diam.)
B. Portion of the same more separated.
regard to the cervical ganglia of man, as men-
tioned by Bonders and Harting. Schaffner
also describes a bipolar cell in the ganglion
Gasseri of the sheep ; and similar cells have
been observed by Corti* and Pappenheim in
the acoustic nerve of the pig, and by Frey in
the Gasserian ganglion of the cat. In the
common trunk of the pneumogastric and
sympathetic nerves in the middle of the neck,
in the young calf, oval cells may be seen which
have distinctly attached at their peripherical
extremity a nerve -fibre ; and some of them
also appear to be connected with one at the
opposite or central extremity.
The different cells composing a ganglion are
each surrounded by a more or less clear, homo-
geneous substance, in which are contained a
number of round or oval nuclei. These are
seen to form a single or double row around
the margin of the ganglionic vesicle, their long
axis being directed in the axis of the cir-
cumference of the cell (fig. 288.). They are
also seen upon the surface of the corpuscle (c,
fig. 288.). This substance not unfrequently
presents a more or less fibrous aspect, as if
composed of spindle-shaped corpuscles. It re-
sembles much (as has been already stated) the
fibres of Remak. The nuclei measure from the
^^Lth to the 4o ] 00 th of an inch in breadth, and
about Tf-gVoth to TTo-o 1 ' 1 f an c h m length.
The structure in question is closely connected
* Kolliker's Mikroskopische Anatomic, band ii.
l\. 519.
with the walls of the included ganglionic cor-
puscle, and appears to hold much the same
Fig. 288,
From the gastric ganglion of the Ray, shewing
ganglionic corpuscles embedded in a nucleated
fibrous tissue.
relation to it that the fibres of Remak hold to
the nerve-tubes. It has been termed the
capsule of the ganglionic corpuscle. The cap-
sules surrounding the different ganglionic cor-
puscles are also closely united to each other,
so as to form a kind of framework, in the loculi
of which the ganglionic corpuscles are placed
0%-288.). It would appear also to be prolonged
along the nerve-tubes connected with the gan-
glionic corpuscles for some distance, forming
for them an investment or sheath similar to
that which it forms for the corpuscles them-
selves. The quantity of this substance which
is present varies in* different circumstances.
It appears to be more abundant in some cases
than in others, and is commonly more so in
the sympathetic ganglia than in those on the
posterior roots of the spinal nerves.
As regards the arrangement of the nerve-
fibres in the ganglia, when one of the^ enter-
ing branches in the ganglia of small animals,
such as the mouse, is traced into the point at
which it joins the ganglion, it is found to
spread out somewhat, and soon breaks up
into its component fibres. These separate
from one another, running amongst the gan-
glionic corpuscles, either singly or in bundles
of two, three, or more. The nerve-fibres be-
longing to one bundle leave it and join neigh-
bouring bundles, so that a more or less com-
plete interchange of the fibres contained in
the different bundles takes place; and at the
same time there is formed a sort of plexus or
network, in the meshes of which the ganglionic
corpuscles are imbedded (fig. 28?.). Some-
times, as Valentin observed, one or more of
the fibres of one of the entering bundles are
seen to wind round the ganglionic corpuscles,
and appear again to pass into another entering
bundle, thus pursuing apparently a retrograde
course. The fibres which thus surround the
ganglionic vesicles were termed by Valentin
umspinnende fasern ; whether they again
really leave the ganglion in the direction in
which they entered it, and in this way may be
regarded as terminating in a looped arrange-
SYMPATHETIC NERVE.
439
mcnt in the ganglion, it is difficult to deter-
mine. Kolliker* has observed that the nerve-
tube arising from a ganglionic corpuscle fre-
quently makes one or two turns around it
before pursuing its course towards the peri-
phery ; arid it appears probable therefore that
many of the so-called umspinnende fasern may
be of this description. That the nerve-fibres
connected with the ganglia do not merely pass
through it between the ganglionic corpuscles,
as was formerly supposed, but enter into
intimate organic connection with these bodies,
either arising from them, or having these
bodies developed upon them in their course
from the centre towards the periphery, as
seems to be the case with most of the bipolar
cells, is quite certain.
Aves. In the bird the ganglia present
much the same structure, both as regards the
ganglionic corpuscles and nerve-fibres, as
those of the mammalia.
Reptilin. In the frog, the animal in this
class which has been most frequently ex-
amined, the ganglionic corpuscles present the
same general characters as those in the higher
animals. The existence of apolar and uni-
polar ganglionic corpuscles is much better seen
in examining the small ganglia in the heart or
bladder of this animal than in the ganglia of
the mammal or bird. Bipolar cells have been
described by Schiff; Valentin f has also de-
scribed and figured bipolar ganglionic cor-
puscles the nerve-tubes of which ran in
opposite directions, one towards the centre,
the other towards the periphery. They were
found by him both in the small ganglia of the
heart, and also in the ganglia occurring in the
main chain of the sympathetic. The nerve-
tube connected with these he describes as
clear and transparent, differing from the broad
nerve-fibres in its colour and general appear-
ance, especially in its not presenting any oily
contents, and thus appearing to belong to
the fine variety of fibres. Kolliker describes
the unipolar ganglionic corpuscles as being
pyriform, and at their narrow extremity drawn
out into a delicate process. This presents
the same pale and finely-granular appearance
as the corpuscle itself, and measures from the
Y^ijr^th to the j-J^g-th of an inch in dia-
meter : after running a short distance from the
ganglionic corpuscle it acquires a dark margin
and slightly granular contents ; becoming, in
short, a fine nerve-fibre (see fig. 289. A).
Bidder has also observed in the ganglia of
the heart of the frog bipolar cells, which,
however, resembled the unipolar in the fact
that both nerve-tubes ran in the direction of
the periphery. In the ganglia of the frog there
is a much smaller amount of the substance
present, which has been described as consti-
tuting the capsules of the ganglionic corpuscle,
and there are also very few of the fibres of
Remak.
Pisces. In certain animals belonging to
this class, especially in the cartilaginous fishes^
* Mikrcskopische Anatomic.
f Valentin, Lehrbuch der Physiologic,
scliweig, 1848 ; band ii. p. 602. et seq.
the 'connection between the ganglionic cor-
puscles and the nerve-tubes is much better
seen than in any of the preceding classes.
In the torpedo and ray the bipolar variety of
ganglionic corpuscles was first discovered by
Wagner, and shortly afterwards by Robin.
Similar observations were also made by Bid-
der and Reichert, both as regards the car-
tilaginous fishes, and, by the latter observer,
in the cod, perch, and certain species of sal-
mon, as well as in the pike.* In the common
ray the ganglionic corpuscles, as occurring in
the spinal ganglia, are generally more or less
round or oval, and are much larger than in
any of the higher animals. They measure
from ^i^th to the ir ^ 7 th of an inch in dia-
meter, and contain a more or less clear viscid
fluid with finely molecular matter. On the
addition of diluted acids or spirit, they be-
come dark and granular. Each of the cells
contains a clear round nucleus, in which there
is also present one, sometimes two, nucleoli.
The contents of the nucleus, like those of the
cell itself, become dark and granular on add-
ing the reagents above mentioned. In se-
veral of the cells there are seen, apparently
on the inner surface of their wall, a num-
ber of round corpuscles, generally clear and
transparent, but sometimes more or less
dark and granular. They measure about the
__i_-th of an inch in diameter, and seem, as
Wagner and Robin describe, to form a single
layer on the inner surface of the ganglionic
corpuscles. The larger of the ganglionic
corpuscles are generally more or less spheri-
cal ; the smaller, on the other hand, present
commonly a more oval shape. Sometimes
between the outer cell-wall and the contents
of the vesicles there is, as Bidder describes,
a clear space, varying in breadth, generally
broadest at the points where the two nerve-
tubes are connected with the corpuscle ; at
other times this space does not appear to
exist, the granular contents of the vesicle
coming close up to the cell-wall (see A.
and v.Jig. 286.). The wall of the corpuscle
appears to be much stronger than that of
those in the higher animals, and is distinctly
prolonged at either extremity into the mem-
brane of the nerve-tube, the two constituting
one continuous structure, agreeing both in
anatomical characters and in their relation
towards reagents. When the ganglion-ve-
sicle is ruptured, so as to allow its con-
tents to escape, its cell-wall collapses more or
less, and often presents the appearance of
lines passing outwards towards the circum-
ference, from a central point (H. Jig, 286.)
this appearance is evidently due to folds in
the membrane. In the clear space which has
been mentioned as sometimes existing be-
tween the cell-wall and the contents of the
ganglionic corpuscle, there are often observed
a number of particles, most abundant at the
two poles of the vesicle, which resemble in
appearance the curd- like contents of the nerve-
* Canslatt's Jahresbericht, 1847, also Wagner's
Braun- Handworterbuch der Physiologic, baud iii. p. 361.
et seq.
F F 4
440
SYMPATHETIC NERVE.
tabes, and are evidently continuous with the
same (c, fig. 286.). Sometimes the granular
contents of the vesicle appear to be prolonged
downwards into the nerve-tube (A. fig. 289.),
Fig. 289.
appear on addition of acetic acid. In other
parts the ganglia contain corpuscles similar to
those already described as occurring in the
spinal ganglia, with the exception that they
are in general perhaps somewhat smaller.
They are imbedded in a fibrous structure,
which seems to hold the same relation to
them as the nucleated substance forming the
capsules of the ganglionic corpuscles in the
higher animals. It is difficult to ascertain
how far the ganglionic corpuscles in the ab-
dominal ganglia are unipolar or bipolar ; ac-
cording to Wagner, they are the same in this
respect as the corpuscles in the spinal ganglia,
being all bipolar ; one tube entering while
another leaves the corpuscle. The nerve-
tubes which are connected with them belong
both to the broad and fine varieties ; in ge-
neral, the narrower fibres are connected with
the smaller corpuscles, the broader fibres \\ ith
those of larger size (fig. 290.).
Ganglionic corpuscles from the gastric ganglion of the
Torpedo. (After Wagner.)
Showing, B, several of the cells still surrounded
by the fibro-nucleated tissue. A, other cells de-
nuded of it.
while at other times, the oily contents of the
latter reach quite up to the corpuscle, and
seem either to become blended with the
granular contents of the same, or are pro-
longed into the clear space. Wagner* be-
lieves that the normal relation between the
nerve-tubes and corpuscles is, that each pri-
mitive nerve-fibre coming from the centre,
retains its appearance of double contour up
to the ganglion-cell, where its contents are
interrupted by the finely granular matter of
the latter; at the peripherical extremity of
the cell, the nerve-fibre commences in a quite
similar manner. Thus then, according to
Wagner, the oily contents of the nerve-tube
cease on reaching the ganglionic corpuscle.
Bidder-}-, on the other hand, regards the clear
white space between the cell-wall and the
granular contents as a thin sheet of nervous
matter, which serves as a connecting medium
between the contents of the nerve-tube on
either side of the ganglionic corpuscle.
As regards the sympathetic ganglia in this
animal, they appear in some parts to be almost
entirely composed of a fibrous structure and
of a quantity of granular matter resembling,
as Wagner and Robin observe, the gray
granular matter of the nervous centres, and
containing a number of bodies of a brownish-
yellow granular appearance, which do not dis-
* Handwb'rterbuch der Physiologie, bandiii. p.
361. et seq.
j- Zur Leben von dem Verhaltnisz der Ganglien,
korper zu den Nervenfasern, Leipzig, as quoted
in Canslatt's Jahresbericht, 1847.
Ganglionic corpuscles from the 2Gth spinal ganglion of
the Torpedo, drawn in utline in order to show the
different size of the nerve-lubes. (After Wagner.)
It has been already seen that it is almost
certain that all the ganglionic corpuscles oc-
curring in the ganglia on the posterior roots
of the spinal nerves, at least in this animal,
belong to the bipolar variety ; it remains to
inquire whether all the nerve-fibres in the
posterior root are connected with ganglionic
corpuscles. When the ganglion, after addition
of dilute solution of soda, is examined with a
powerof about 30 or 40 diameters, itis observed
that while many of the fibres soon disappear
among the ganglionic corpuscles, several of
them can be traced from the point at which
they enter the ganglion almost to its opposite
extremity, without being connected with cor-
puscles ; but I have never been able to trace
them in this manner quite past the ganglion.
Wagner, who counted the nerve-tubes con-
tained in the posterior root of the nerve and
also the ganglionic corpuscles, found that the
number of each corresponded pretty closely,
SYMPATHETIC NERVE.
441
so that he believes each of them is connected
with one of these bodies.
Invertebrata. The ganglionic corpuscles
in the ganglia of the invertebrata appear to
be the same in their essential characters as
those of the vertebrate animals. Will* re-
cognises two kinds of ganglion-corpuscles in
the lower animals. The one he describes as
consisting of a membrane and nucleus, the
space between the two being occupied by a
clear transparent fluid, which becomes granular
on the addition of water ; in the other variety
there are imbedded in the clear transparent
fluid numerous small round cells in which no
nucleus is visible. The cells belonging to the
former variety have always but one process
attached to them which consists of a single
tube, presenting no division so far as it can
be traced, and thus corresponding to the uni-
polar variety of corpuscle. In the second
kind of corpuscles there are several such pro-
cesses present ; the processes attached to
some of these cells all run in one direction ;
in others they pass off at either extremity
and run in opposite directions. In the leech,
according to Bruch-f-, there are also two kinds
of ganglion corpuscles. The one variety are
round and are apolar ; the others are con-
nected with nerve-fibres. The latter are situ-
ated towards the lower part of the ganglia,
and are more numerous than the former: they
are more or less pyriform, their wider ex-
tremity being directed outwards ; their nar-
rower, terminating in a process, is directed
towards the ganglia and the nervous cord.
Peripherical ganglia, consisting of from one
to six or seven cells, are always found at the
points where the branches of the nerves di-
vide. Ganglionic corpuscles were also seen
by him in the interior of the nerve-tubes, and
corresponding to the view taken by Bidder J
of the constitution of the bipolar ganglionic
corpuscle. Apolar and unipolar cells have
also been described by Hannover and Leydig
in several other invertebrate animals.
From the fact that in such animals as the
torpedo and ray, where the ganglionic cor-
puscles are easily isolated from each other,
they are all found to belong to the bipolar
variety, Wagner, Robin, and Bidder believe
that all the ganglionic corpuscles in other
animals are also bipolar. Kolliker, on the
other hand, while he admits that the bipolar
cell is most frequent in the fish, maintains
that the opposite is the case as regards the
higher animals, most of the corpuscles in
them belonging either to the apolar or uni-
polar varieties; and so far as actual observa-
tion goes, the views of Kolliker seem to be
perfectly correct, inasmuch as, while apolar
and unipolar cells are very frequently seen in
these animals, the bipolar variety has been
seen very seldom. It is possible, however,
that many of these unipolar and apolar cells
may, as Wagner and Bidder, &c. hold, be
really bipolar cells, one or both nerve-tubes
* Miiller's Archiv. 1844, p. 76. also in Canslatt's
Jahresbericht, 1847.
t Ibid. t Ibid.
having been broken off during the manipula-
tion required for submitting them to examina-
tion. In the spinal ganglia of the ray the
cells are very easily isolated from each other,
whereas in the abdominal ganglia it is very
difficult, owing to the amount of surround-
ing fibrous structure, to isolate them. Now
in the former only bipolar cells are seen,
whereas in the latter, most of the cells, when
isolated, appear to be unipolar and apolar,
although it would appear from the observa-
tions of Wagner and others, that they are all
bipolar, like those in the spinal ganglia. In
the higher animals, especially in the mam-
malia, the ganglionic corpuscles are isolated
from one another with as much difficulty as
those in the abdominal ganglia of the skate ;
and hence the probability that many at least
of the unipolar and apolar cells which are seen
in them, belong to the bipolar variety in
reality. On the other hand that apolar and
unipolar ganglion -corpuscles really exist, and
that too in considerable numbers, in the gan-
glia of the higher animals, and also in those
of the invertebrata, seems to be shown by
numerous observations on the smaller gan-
glia, where no preparation is required, and
where, consequently, the above source of
fallacy cannot intervene. In the sympathetic
cord of the frog, according to Valentin *,
groups of ganglionic vesicles may be observed,
without a single nerve-fibre connected with
them : Ludwig f has also observed in the au-
ricle of the frog's heart small ganglia in which
there were eleven gangtionic corpuscles, and
only four or five nerve-tubes ; in a nerve
passing to the bladder of the frog, and con-
sisting of only two nerve- fibres, Valentin
counted as many as seven ganglionic cor-
puscles, | while another, consisting also of
only one or two nerve-fibres, was surrounded
by twenty-four ganglionic corpuscles.
In accordance with the view adopted by
Wagner, that all the ganglionic corpuscles are
bipolar, the nerve-tube connected with either
extremity of the cell running in opposite
directions, one towards the centre, the other
peripherically, Robin believes that all nerve-
tubes arise exclusively from the brain and
spinal cord ; neither the spinal ganglia nor
those of the sympathetic give origin to nerve-
tubes; the ganglion-cells are merely organs
developed upon the nerve-tubes, between
their central and peripherical termination, and
several such may be present on a single nerve-
fibre during its course. From what has been
already stated, however, it seems probable
that unipolar as well as bipolar cells exist in
the ganglia, and consequently that nerve-
tubes do originate in them. That nerve-fibres
arise in the ganglia, is further shown by the
accurate measurements of Volkmann and
Bidder of the nerves passing to and those
leaving the ganglia. The ciliary, Gasserian, and
spinal ganglia in the frog were found by them
to give off a far greater number of fine nerve-
* Lehrbuch der Physiologic; Braunschweig,
1848 ; band ii. p. 602.
f Mailer's Archiv. 1848, p. 142.
442
SYMPATHETIC NERVE
fibres on the one side than they received on
the opposite side. So also in the septum
between the auricles of the frog's heart
Bidder has seen small ganglia, which gave off
on Hie one side eight nerve-fibres more than
they received on the other side. The obser-
vations of Bidder and Volkmann have been
confirmed also by Kolliker. Engel*, moreover,
describes a peripheral ganglion, to which no
nerve-fibres passed, while a number of fibres
left it; an observation which, if correct, places
beyond a doubt the question as to the origin
of nerve-fibres in the ganglia. The ganglion in
question he describes as being pear-shaped,
and about 0*096 of a line in diameter ; it oc-
curred in the perichondrium of the tracheal
cartilage, and consisted of fourteen ganglionic
corpuscles, with seven efferent nerve-fibres,
each measuring about 0*0012 of a line in
diameter. Even in regard to the bipolar gan-
glionic corpuscles, it does not appear to be at
all certain that they are all merely organs deve>
loped on the course of a nerve-fibre arising in
the brain and spinal cord. On the contrary,
it would appear that several of the cells be-
longing to this variety must also be regarded
as giving origin to nerve-fibres in the same
manner as the unipolar cell. Thus Bidder
has seen bipolar cells, the nerve-tubes con-
nected with which did not run in opposite
directions, one towards the brain and spinal
cord, the other towards the periphery, but
both ran in the latter direction (fig. 291.) : so
also Stannius, as mentioned by Kolliker, has
Fis. 291.
Bipolar ganglionic corpuscle, Loth nerve-fibres con-
nected with which run peripherically. From the
spinal ganglion of a Fish. (After Bidder.}
seen in the ciliary ganglion of Trigla, a bi-
polar cell, both nerve-fibres of which were
directed peripherically. The same observer
has also seen ganglionic corpuscles in the fish
which gave origin to or had three nerve-tubes
connected with them.
That most of the bipolar cells are, how-
ever, as Robin maintains, organs developed
on nerve-fibres of cerebro-spinal origin, in
their course towards the periphery, there is no
* Engel in Zeitschrift der Wien. Aerzte, iv. p. 307.,
as quoted in Kolliker's Mikroskopische Anatomic,
p. 532.
reason to doubt; and moreover that several of
these may occur in the course of a single
fibre between its central and peripherical ter-
mination is also shown by the observations of
Stannius on [the fish, and by Valentin on
the frog. Wagner has also observed two
ganglion-corpuscles occurring in the course
of a single nerve-fibre, at short distances from
one another.
Robin* divides the ganglionic corpuscles
into two distinct classes, a larger and a smaller :
the larger he finds always occur on broad nerve-
fibres, or fibres of animal life, while the smaller
are always connected with nerve-fibres be-
longing to the finer variety, or fibres of or-
ganic life ; and in this way, according to him,
we have a good mark by which to distinguish
the animal from the organic nerve-fibres. In
the ray, according to Robin, the larger variety
of corpuscles measure 0'095 to 0*150 mm. in
diameter, are spherical, and often flat at both
poles; the smaller measures 0*080 to 0*115
mm. in length, and 0*050 to 0*070 mm. in
breadth, and are commonly oval. , In the
larger cells there is a layer of clear round
bodies, without nuclei; in the smaller gangli-
onic corpuscles the outer membrane is finer,
and each of the cells, on their inner sur-
face, . is provided with a central dark nu-
cleus. Bidder f also agrees with Robin in
separating the ganglionic corpuscles into two
groups. In the pike the one set measure
O'O^"', while the other set do not measure
more than 0*0 18 //r : the former chiefly occur
in the ganglia of the cerebro-spinal nerves,
the latter in the ganglia of the sympathetic ;
the former are always connected with broad
fibres, the latter with fibres belonging to the
fine variety. The views of Robin and Bidder
are opposed by Kolliker, Valentin, and ap-