76 CONVOLUTIONS OF THE BRAIN CHAP. 
very marked feature, moreover, of the mammal’s: brain is the 
development of regular fissures upon its surface, which fissures 
are only absent from Ornithorhynchus, various small Rodents, 
| 
Hyp I Lo VIVE 
Fra. 49.—Brain of Dog. A, ventral ; B, dorsal ; C, lateral aspect. 6.0/7, Olfactory lobe ; 
Or.ce, crura cerebri; Fi.p, great longitudinal fissure; HH, HH, lateral lobes of 
cerebellum ; Hyp, hypophysis ; Med, spinal cord; NH, medulla oblongata ; Po, 
pons Varolii ; VH, cerebral hemispheres ; Ww, middle lobe (vermis) of cerebellum ; 
I-XiI, cerebral nerves. (From Wiedersheim’s Comparative Anatomy.) 
Bats, and Insectivores, among hving mammals. It is some- 
times, but erroneously, said that the more complicated the 
fissures of the brain are, the higher in intelligence and “ zoological 
position” is the possessor of that brain. Instances can un- 
doubtedly -be quoted to support such a view; but they are 
