AND PHYSIOLOGY. 



35 > 



COMPARATIVE NEUROLOGY. 



654. Among all the higher 

 mammals we are able to trace 

 nearly all the different parts 

 of the nervous system as they 

 are exhibited and arranged in 

 man, though many of them 

 are considerably modified. 



655. Weight of Brains.— 

 The relative weight of the 

 brain is greater in the smaller 

 animals/ Thus, in the mouse 

 it is said to be ^d the weight 

 of the body. In the elephant 

 the weight of the brain is 



Fig. 329. 



Brain of Squirrel laid open. B, Cere- 

 brum. D, Cerebellum. C, Optic Lobes. 

 thai., Thalamus Opticus. c, s, Corpus 

 Striatum. 



FlO. 330. 



Upper and Under Surface of Brain of Rabbit. A, B, D, as before. ol, Olfactive Lobes. 



op, Optic Nerve, mo. Motor Oculi. cm, Corpora Mamillaria. c, c, Crus Cerebri. pv> 



Pons Varolii, pa, Pathetieus. tri, Trifacial, ab, Abducens. fac, Facial, au, Audi- 

 tory, tag., Vagus, s, Spinal Accessory, hyp., Hypoglossal. 



655. What is said of the size of brains? 



