MR. R. OWEN ON THE ANATOMY OF THE CHEETAH. 1338 
respect to the brain of the Cheetah, I am disposed to offer my remarks somewhat more 
in detail. 
A remarkable uniformity in the structure of this organ prevails throughout the 
genus Felis, so far as I have yet had the opportunity of observing it ; and this uniformity 
obtains not only in the general form of the cerebral hemispheres and of the cerebellum, 
and in the relative proportions of these parts to the bigeminal bodies and medulla ob- 
longata, but in the number and disposition of the convolutions of the cerebrum. The 
brains which I have compared for this purpose, are those of the Lion, Tiger, Puma, 
Cheetah, and several of the domestic Cat. 
The hemispheres of the brain cover about the anterior half of the cerebellum, having 
an osseous tentorium intervening: the mass of cerebrum posterior to the corpus callosum 
exceeds that which is anterior to the same by about one fifteenth part of the longi- 
tudinal diameter of the cerebrum. The superior vermiform process occupies a little 
more than one third of the transverse diameter of the cerebellum. Of the bigeminal 
bodies the posterior pair is the largest, while, as Tiedemann has observed, the contrary is 
the case in the Rodentia, Ruminantia, and Solipeda. The corpora candicantia are blended 
into a single mass, as in most of the Mammalia inferior to Man. The transverse tract 
posterior to the tuber annulare, and bisected by the corpora pyramidalha, from which the 
seventh and auditory nerves arise, called corpus trapezoideum, is of remarkable size in all 
the species of the genus Felis above mentioned. The outer root of the olfactory nerve 
is of great size, and emerges from a remarkably prominent natiform protuberance. 
After premising these leading characters in the feline brain, I shall proceed to de- 
scribe in detail the disposition of the superimposed cerebral matter of the hemispheres : 
and as this is extended from before backwards in the process of growth, I shall begin 
with the fissures on the anterior part. In the common Cat the principal fissures, or 
anfractuosities, are less obscured by fissures of the second degree, and by vascular 
grooves, than in the higher Feles. 
The first or most anterior anfractuosity on the superior surface of the brain is lon- 
gitudinal, and being the continuation and termination of the principal one on the in- 
ferior surface, it extends a very short distance from before backwards!. The next an- 
fractuosity behind this is a transverse one®, extending from the middle line about two 
thirds across the hemisphere. At a short distance behind this fissure an anfractuosity 
commences, which extends backwards parallel with the falz cerebri, and which follows 
to a greater or less extent the outline of the posterior lobe of the hemisphere. The ante- 
rior end of this anfractuosity? is crossed by an oblique fissure, which varies in extent. 
Parallel to the mesial longitudinal anfractuosity, and at the same distance from it as 
the latter is from the falz, a second longitudinal anfractuosity* is seen, which does not 
extend so far forwards or backwards, but bends outwards and downwards at both ex- 
tremities. The mass of cerebrum external to the second longitudinal anfractuosity is 
1 §, Figg. 1—5, Plate XX. 21. Figg. 1—6. 32. Figg. 1. 2. 4. & 5. 43. Figg. 1. 2,4. & 5. 
T2 
