476 



J. B. JOHNSTON 



Fig. 88 Diagram of the brain of the mole. Although there is a large corpus 

 callosum and a splenium is well formed, there is an unusually large primordium 

 reaching almost the entire length of the corpus callosum and connecting with 

 the hippocampal flexure. The boundary of the paraterminal body as it appears 

 in the ventricular surface is represented here. Reference to figure 55 will show 

 that the medial parolfactory nucleus rises much higher on the outer surface. The 

 diagram of the rat brain following is drawn with reference to the boundary on 

 the outer surface. 



Fig. 89 Diagram of the brain of the rat. The gradual merging of the indu- 

 sium beneath the genu with the primordium is represented by tooth-like projec- 

 tions. The paraterminal body rises higher on the medial surface than it does 

 next the ventricle. On the ventricular surface the boundary line runs almost 

 straight forward from the neuroporic recess. 



