Metasoa Ran a. 311 



(p. 317), has a ganglionic swelling upon it. The first spinal 

 nerve is known as the hypoglossal, from the fact that it is 

 distributed to the muscles of the tongue ; the next two 

 (brachial plexus) supply the fore-limbs ; the fourth, fifth, 

 and sixth are distributed to the muscles of the body-wall ; 

 the next three go to the hind-limbs and parts in the vicinity ; 



FIG. 168. -SPINAL CORD (ox). (Quai-i.) 



A, antero-posterior v'ew; B, lateral view; c, transverse section ; D, uni^n 

 of the two roots of a spinal i.erve. i, anterior fissure ; 2, posterior 

 fissure ; 3, origin of anterior root (5) ; 4, origin of posterior root (6) ; 

 6'. ganglion on the posterior root ; 7, 7', sensory and motor nerves. 



while the tenth and last supplies the region of the urostyle 

 and cloaca. 



In addition to the cerebro-spinal nervous system thus 

 briefly sketched there is another visceral or sympathetic 

 nervous system, consisting of a double chain of ganglia 

 connected by commissures to each other and to the cerebro- 

 spinal nerves, and lying in the dorsal region of the ccelom, 



