(344) 



24. Nervous system of Amphibia 



The organization of the nervous system of amphibia might be said 

 to be essentially similar to that of fishes. In both groups there are 

 highly developed special centres in the brain, each centre related to a 



verb. 7. 



n.S 



n.10 



n.11 



Fig. 202. Ventral branches of the spinal nerves (2-1 1) of the frog. The sympathetic chain 



is also shown. 



g.X, vagus ganglion; int. a. intestinal artery; n.spl. splanchnic nerve; n. (2-1 1), spinal nerves; 

 sub. subclavier artery, sym. sympathetic chain; vert. 1, 1st vertebra. (After Gaupp.) 



special receptor system. In neither group is there a dominant part, 

 integrating the activity of the whole, as does the cerebral cortex in 

 mammals. 



The plan of the spinal cord is like that of fishes, but well-marked 

 dorsal and ventral horns are present. The large motor-cells of the cord 

 have dendrites that spread widely in the white matter, where their 



