506 ON THE BRAIN OF ATELES PANISCUS 
more away from the vermis superior. The anterior and posterior 
notches are almost obliterated, the posterior extremity of the vermis. 
extending very nearly as far back as the level of the posterior edges 
of the cerebellar hemispheres. The transverse diameter of the vermis 
is much greater, in proportion to the whole diameter of the cerebellum,,. 
than in Man, and the vermis inferior presents no such sharp distinc- 
tion into pyramid, uvula, &c., as in the human subject. The great 
horizontal fissure is distinct and tolerably deep; but I could discover 
no definite minor fissures, and consequently no demarcation of the 
upper, or under, surfaces of the hemispheres into lobuli. There are 
not even any distinct lobules, as amygdala, beside the uvula. On the 
other hand, the flocculi are enormous, and end in prominent rounded 
processes, which fit into deep fossae upon the inner surfaces of the 
petrosal bones. 
A distinct posterior medullary velum was visible on each side, con- 
necting the nodule with the flocculus ; and the valve of Vieussens, as 
usual, united the processus e cerebello ad testes. The arbor vitae was 
well-marked and complex in its branchings, in a vertical median 
section of the cerebellum. 
Of the corpora quadrigemina the nates are smaller than the testes ; 
but the branchia superiora are larger than the branchia inferiora, on 
which latter the corpus geniculatum internum looks almost like a 
ganglion. 
The pons is large and convex, but nevertheless leaves tolerably 
well-defined corpora trapezoidea upon the surface of the sides of the 
medulla oblongata, which last exhibits distinct oval olivary bodies. 
The pituitary body, very large and spheroidal, is connected with a 
prominent infundibulum, which is separated by a slight transverse 
notch from the single corpus mammillare. 
The commissures, third ventricle, pineal gland, &c. presented 
nothing remarkable. The nerves are large in proportion to the brain, 
particularly the olfactory nerves (which are very broad and flat), the 
optic nerves, and the oculo-motor nerves; but beyond their large 
size they differ in no striking respect from the corresponding parts. 
in Man. 
