The Nervous System 135 



gins of the other cranial nerves were described in 

 connection with the lateral view of the brain, where 

 they show more clearly. On each side of the cere- 

 bral peduncles is seen the ventrolateral edge of 

 the corresponding optic lobe. The pyramidal 

 tracts are seen, extending caudad from the region 

 of the peduncles, as a swelling on each side of the 

 median ventral fissure. 



THE CRANIAL NERVES (CROCODILE) 



The origin of each of the cranial nerves was de- 

 scribed in connection with the lateral and ventral 

 views of the brain. A full description of the 

 distribution of these nerves would require more 

 space than the limits of this book will allow, but 

 a brief account will now be given. 



I and II. The olfactory and optic nerves. 

 These two large nerves go immediately to their 

 respective sense organs, so that no further discus- 

 sion of them need be here given. 



III. The oculomotor nerve. The single stem 

 divides into three branches: a median, going to 

 the externus rectus muscle; a lateral, going to the 

 inferior rectus muscle; and an intermedial, going 

 to the inferior oblique muscle. 



IV. The trochlear (pathetic) nerve leads to 

 the superior oblique muscle. 



V. The trigeminal nerve. The distribution 

 of this nerve is very complicated. It has three 



