268 



THE BRAIN OF QUADRUPEDS AND 



At the anterior part of the floor of each Lateral Ven- 

 tricle, is the rounded prominence known as the Corpus 

 Striatum. These bodies vary much in size in animals of 

 different orders. They are small in Marsupials, and are 

 in them partly overlapped hy another well- developed pro- 

 jection known as the Hippocampus Major a body 

 corresponding with, and produced by, a deep depression 



FIG. 83. 



PIG. 84. 



FIG. 85, 



FIG. 83. Brain of a Chelonian. FIG. 84. Brain of a Foetal Calf. FIG. 85. Brain of 



a Cat. 



These three figures, from Gegenbauer, illustrate the comparative development of 

 the Cerebral Hemispheres and related parts. In Figs. 83, 84, the roof of the Lateral 

 Ventricle is removed on the left, and the Fornix and Hippocampus also on the right. 

 In Fig. 85 the whole lateral and posterior portions of the right Hemisphere are 

 removed, and as much on the left as is necessary to display the upward bend of 

 the Hippocampus. In all the figures I marks the Cerebral Hemisphere ; II, the 

 Thalamus ; III, the Corpora Quadrigemina ; IV, The Cerebellum ; V, the Medulla. 

 o I, Olfactory lobe (shown in Fig. 83 as communicating with the Lateral Ventricle) ; 

 s t, Corpus Striatum ; /, Fornix ; h, Hippocampus ; s r, fourth ventricle ; g, geniculate 

 body. 



or fissure on the inner surface of the Hemisphere the 

 ' fissure of the Hippocampus.' In Hares also the Cor- 

 pora Striata are small, while the Hippocampi are large. 

 The latter bodies are remarkable for their great size in 



