CLASS AMPHIBIA 



525 



Nervous System 



The three divisions in which the nervous system of the bullfrog 

 may be considered are: (1) central nervous system, (2) peripheral 

 nervous system, and (3) sympathetic nervous system. 



o/facb3ry tracb 

 .oifflct»rylobe' 



Cerebrum 



Optic nerve 



Pineal body 



J)/Gnccphalon 



i^tic lobe 



Cerebellum 



Nedulla oblongata 



4Lh ventricle 



Jjlossophatynqeal 



.Vacjof nerve 



J^ spinal nerve 



22^ jpinal nerve 



Trigeminus 



Facia/, 

 Auditory 



Thoracic 

 enlargement 



} 



Brachial 

 plexus 



5piT)at cord 



Lambar. 

 enlargement 



^ 5'^ jpinal mrve 



.+^ .spinal nerve 



_ JZalcareoui body 

 5S! jpinal nerve 



,.6t2) ipinal nerve 



^ spinal nerve 



-_a*-bjpinal nerve 



5 — spinal nerve 



jotb jpinal nerve 



Sciatic plexus 



Jdatic nerve 



Fig. 285. — Dorsal view of the nervous system of a frogr. 



The central nervous system, so called because it comprises the 

 larger number of nerve centers, consists of the brain and spinal cord. 

 The peripheral nervous system consists of (1) the paired cranial and 

 spinal nerves which connect the brain and spinal cord with other 



FiJumterminale. 



