174 PROF. W. H. FLOWER ON THE MUSK-DEER. [ Mar. 16, 
The Brain. 
The brain presents the usual characters of that of an ordinary Deer 
(Cervus mezicanus, Mus. Roy. Coll. Surg. no. 1328 E a, was the 
species with which I compared it most closely), but, in accordance 
with its smaller size, much reduced in complexity of surface inden- 
tations. A natural group like the Cervid@, containing animals vary- 
ing much in dimensions, is well adapted to demonstrate how closely 
the amount of convolution bears relation to the bulk of the hemi- 
sphere, the primitive pattern being exactly the same in all, The 
Upper surface of brain, natural size. 
s s, superior external gyrus; 7, middle external us; 72, inferior external 
, Pp By ’ 
gyrus; h, hippocampal gyrus. 
brain of C. tarandus (Mus. Roy. Coli. Surg. no. 1328 E) is far more 
abundantly supplied with secondary surface-windings (even so as very 
much to obscure the general outline of the pattern) than is that of 
C. mexicanus. The latter and C. dama(Leuret & Gratiolet, ‘ Anat. 
Comp. du Systeme Nerveux,’ pl. x.) are almost exactly alike. C. ea- 
preolus (ibid.) is more simple, and Moschus moschiferus still more so. 
The most obvious division of the external surface of the hemisphere 
is into three longitudinal tracts. The lowest (4), continued from the 
