214 



FIRST L/LSSONS IN ZOOLOGY 



1 lie ra)s and skates arc peculiar ocean fishes, which 

 lie at the bottom of sliallow shore-waters. They feed on 

 crabs, molluscs, and bottom-fishes. The small common 

 skates, " tobacco-boxes " (fig. 174), about twenty inches 



long, and the larger 

 "barn-door" skates are 

 numerous along the At- 

 lantic coast from Virginia 

 northward. Especiall}' in- 

 teresting members of this 

 group, because of the pe- 

 culiar character of the in- 

 juries produced by them, 

 are the sting-rays and tor- 

 pedoes, or electric-ra)-s. 

 The sting-rays have spines 

 near the base of the tail 

 which cause very painful 

 wounds. The torpedoes 

 have two large electrical 

 organs, one on each side 

 of the body, just behind 

 the head, with which they 

 can give a strong electric 

 shock. " The discharge 

 from a large individual is 

 sufficient to temporarily 

 disable a man, and were 

 these animals at all nu- 

 merous they would prove dangerous to bathers." Ver}' 

 different from the tj'pical rays in external appearance are 

 the sawfishes, which belong to this group. The body 

 is elongate and shark-like, and has a long, saw-like 

 snout. This saw, which in large individuals may reach 

 a length of six feet and a breadth of twelve inches, 



Fk;. 173. — A srii.liur;.!.-, Hipp, mi 

 ie//o:;i;i. (Tlii^ fi-h is riglil ii 

 long; ,'d'ter Jordan and Snyder.) 



HtpliS 



