58 
ANIMAL PATHOLOGY. 
gangliform enlargement. This at once stamps their character. 
They proceed, like the glosso-pharyngeus, from that portion of the 
cord whence spring the motor nerves — they arise in distinct but 
minute filaments, in a line, like the motor nerves — and ere they 
quit the cranium they pass through a ganglion. They com- 
bine the characters of both nerves; they excite motion, and they 
convey sensation. 
The Course of the Nerve . — This nerve, as it quits the dura- 
mater, lies between the glosso-pharyngeus and the spinal acces- 
sory : it is somewhat separated from the former by a portion of 
the dura-mater, and is contained in the same sheath as the lat- 
ter. It has scarcely escaped before it communicates with the 
glosso-pharyngeus, the spinal accessory, and the ganglionic 
nerves. We shall see that it is slightly connected in function 
with the second, and most intimately so with the first and last 
of these. 
The Pharynx. — The communication with the spinal acces- 
sory is first formed. The nerve bends itself downwards and in- 
wards, in a direction towards the pharynx ; and in pursuing this 
course, it communicates with or receives a branch from the 
spinal accessory. It is going to the pharynx, and it seems to be 
securing the agency and assistance of the muscles to which the 
spinal accessory goes, for the accomplishment of the function of 
the pharynx — that of deglutition. We easily recognize the ac- 
tion of the trapezius in the forcible effort to swallow, and more 
particularly in sheep and cattle. Proceeding onwards, and near 
the pharynx, it anastomoses with — two or three, some say ; I 
would rather state with — many minute branches from the glosso- 
pharyngeus, from the superior laryngeal nerve to be presently 
described, and from the ganglionic nerve, and they form that 
plexus behind the middle constrictor muscle on which the action 
of the pharynx mainly depends, and from which fibrils are dis- 
tributed to the remainder of the constrictor apparatus of this 
part — the stylo, and the palato-pharyngei muscles, which are 
under the influence of the glosso-pharyngeus, having previously 
dilated it. In order to secure the right performance of the act 
of deglutition, branches are received from a nerve of voluntary 
power — the lingual nerve. They are particularly distributed to 
the stylo-pharyngeus, and to the constrictor pharyngeus supe- 
rior. The act of deglutition thus becomes in some measure de- 
pendent on the will, and the more forcible action of certain mus- 
cles is thus secured ; and, before the will has power over them, 
they are called into action by the excito-motory power of the 
great spinal organic nerve. 
In another way the act of deglutition is under the influence of 
