THE 
VETERINARIAN. 
VOL. VI, No. n.] NOVEMBER, 183.3. [New Series, No. ll. 
MR. YOUATT’S VETERINARY LECTURES, 
DELIVERED AT THE UNIVERSITY OF LONDON. 
LECTURE XXXVII. 
The Cerebellum—Tom Varolii—Medulla Oblongata, and Intvo' 
ductory Observations on the Serves, 
I HAVE stated in a former lecture, that there is only an ap¬ 
parent difference in the relative situation of the cerebrum and 
cerebellum in the biped and the quadruped ; that in both the 
cerebellum is the portion nearest the foramen magnum, and- 
under which the crura cerebri must pass in order to arrive at the 
medulla oblongata and spinal chord. I have also spoken of the 
relative size of the cerebrum and cerebellum in different animals ; 
in the biped, the cerebellum being comparatively small, one- 
ninth part only of the bulk of the cerebrum—in the ox the same 
proportion being observed—the cerebellum increasing in size in 
the dog, the horse, and the sheep, until, in the last animal, it 
becomes a full fifth part of the weight of the brain. We will 
now see what light a consideration of the structure and functions 
of the cerebellum will throw on the matter. 
Description of the Cerebellum. —The cerebellum is apparently 
and partially divided into three lobes; two of which alone are 
visible in the. human being, w^hile the third or central one is co¬ 
vered by the lateral ones : but as the whole cerebellum increases 
in bulk in the quadruped, the central lobe does so in a peculiar 
manner, and is apparently broad and prominent. Its anterior 
and posterior extremities (the vermiform processes) are bulkier 
and more elongated. The vermiform processes of the central 
lobe are quite separated from the lateral lobes; and both of them 
curl up like the extremities of a great worm under the base of the 
cerebellum : the separation extends a little way beyond the pro¬ 
cesses, and more particularly from the posterior process. Before, 
however, we arrive at the centre of the cerebellum from the pos¬ 
terior process, and ere we have scarcely left the anterior one, 
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