212 



ANATOMY OF THE CENTRAL NEETOUS SYSTEM. 



into the convolution of the cornu Ammonis. This is the olfactory drain. 

 In the armadillo — and in the dog, rabbit, and many other mammals also — 

 it is much larger than in the calf. It then nearly always occupies the entire 

 base of the brain. This is the same part of the brain which, in reptiles, first 

 made its appearance as a separate region of the mantle. See Chapter XII, 

 pages 170 and 171. 



The fila olfadoria, cut off unevenly in the specimen, enter the anterior 



Fig. 141. — The base of a calf's brain. The ventricle purposely opened from 

 below in order to show its recesses: the R. opticus, infundibuli, and mamillaris. 

 Bieclibiindel, olfactory bundle. 



part. The hulbus olfadorius is shortly met with. This rests upon the lolus 

 olfadorius anterior, the frontal division of the entire apparatus. The lobus 

 olfactorius anterior then passes over into the Joins olfadorius posterior, 

 which is particularly well defined in the armadillo (Dasypus). In Fig. 141 



