•236 
ANIMAL PATHOLOGY. 
evidently involved. It may have something to do with the 
protrusion of the tongue, but it has far more to do with the dread¬ 
ful affection of the fauces which we find in many dogs. It acts 
not only as a motor nerve, but as one of the excitor ones, if the 
new theory of Dr. Marshall Hall is admitted. 
In the perverted action of the superior, and inferior or recurrent 
laryngeal branches, of the great spinal organic, or pneumo- 
gastric, we recognize many of the most dreadful symptoms of 
rabies in the quadruped—the involuntary howling—the husky, 
grating inspiration—the frequent inflammation of the trachea, 
and the uniform one of some part of the glottis in the quadruped, 
and the characteristic and horrible access of hydrophobia in 
the human being. In the morbid action of the nerves of the 
pulmonary plexus we find sufficient illustration of the laborious 
action of the lungs and the peculiar inflammation of the pleura; 
while, to the influence of the gastric nerves is to be traced the 
constant and often intense inflammation of the stomach. 
These nerves anastomose freely with the cerebral nerves, and 
therefore cerebral affection soon occurs. There is a state of gene¬ 
ral and extreme excitation—a very peculiar wandering and 
delirium, and, in some animals, fits of savage and uncontrollable 
ferocity; but few post-mortem lesions of these are observed. 
All these nerves unite and blend with the ganglial ones, and 
thence proceed altered secretion generally ; a morbid secretion of 
the gastric juice, occasioning the strangely perverted appetite 
of the dog ; and a still more depraved one of the saliva, converting 
that bland and innocuous fluid into the direst poison. 
But I will not detain you longer with this anatomical delinea¬ 
tion. It was, however, necessary to place this subject on its 
proper footing. Rabies in the brute, and hydrophobia in the 
human being, may be occasionally accompanied by a considera¬ 
ble degree of febrile excitement; but they are esseiitially of a 
nervous character. The nervous system is irritated, and finally 
exhausted, by some morbific agent. What that agent is, or what 
is the cause of rabies, will form the subject of our next lecture, 
and a more important one the whole circle of veterinary pathology 
does not contain. I shall endeavour to bring to it a candid spirit 
of inquiry ; but it is one of those fundamental points on which it 
behoves the veterinary instructor to deliver his opinion freely and 
unhesitatingly. 
