35 VERTEBRATES: FISHES. 



The Genus Zygcsna has the head flattened horizontally, 

 with the sides much extended laterally. The Hammer- 

 Fig. 241. Fig. 242. 



Head of Hammer- 

 head. 



Hammer-head, Z. malleus, Val. 



head Shark, Z. malleus, Val., attains the length of twelve 

 feet, and is bold and ferocious. 



The Genus Pristis has a very long, depressed snout, 

 armed on each side with pointed spines, planted like teeth. 



Fig- 243- 



Saw-Fish, P. antiqiiorinn, Lath. 



The Common Saw-Fish, P. autiquorum, Lath., attains 



the length of fifteen feet. 



Fig. 244. 



Sting Ray, Trygon hastata, Storer. 



RAIID.E, RAY OR SKATE FAMILY. This Family com- 



