290 



THE NERVOUS SYSTEM 



matter where its fibers rise from nerve cells, and a super- 

 ficial origin, which is the region of the brain surface from 

 which the nerve, as a nerve, departs upon its mission. 



1. The first pair of cranial nerves are the olfactory 

 nerves, distributed directly and wholly to the organ of 

 smell, and sensory in function. 



Olfactory Bulb 



(to which is attached 

 the Olfactory Nerve) 



Pituitary Body ___ 



Optic Nerve- 

 Optic Chiasma 

 Oculomotor Nerve- _ 



Trochlea r Nerve 



Trigem inal Nerve _ 



Pans Varolii 

 Abducena Nerve 



Facial Nerve 

 Auditory Nerve- ^ __ 

 Glossopharyngeal Nerve __ J 

 Vagus Nerve---. 

 Spinal accessory Nerve- - 

 Hypoglossal Nerve- - 

 Medulla Oblongata-- 

 First Spinal Nerve 



Cerebellum 



Spinal Cord- - 

 Second Spinal Nerve 



fig. 134. Ventral anterior, surface of the brain. 



2. The optic nerves go to the organs of sight. From 

 their deep origins to the point where a part of their 

 fibers cross they are called the ' optic tracts. They are 

 sensory. 



3. The oculomotor nerve supplies all the muscles of the 

 eyeball except the superior oblique and external rectus, 



