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GENERAL ZOOLOGY 



ORDER 3. TESTUDINATA (CHELONIA) 



The turtles and tortoises (Fig. 100) are clearly distin- 

 guishable from all other reptiles by the beak-like, toothless 

 jaws and by the shell covering the body. The turtles are 

 aquatic, some species never going on land except to breed, 

 and the tortoises are terrestrial. All chelonians lay eggs, 

 which are buried in shallow excavations on sandy beaches 



Fio. 100. Testudinata. A, the common painted turtle; B, Soft-shell turtle; 

 C, Snapper; D, turtle eggs; E, terrapin. 



or on hillsides (D). Their food varies greatly: the giant 

 tortoises of the Galapagos Islands subsist on cactus; cer- 

 tain marine turtles eat molluscs, fishes, and seaweeds; the 

 fresh- water species feed upon vegetation, molluscs, cray- 

 fishes, insects, fish, frogs, snakes, birds, mice, rabbits, etc. 

 In the interior of the United States there are a number 

 of species of chelonians. The snappers (C) are rough- 

 backed ferocious animals. The common species in the 

 north (Chelydra serpentina) does not weigh over forty 

 pounds, but the southern alligator snapper (Macrochelys 



