304 



REPTILIA 



Natural History 



Super-Order 2. Chelonia. — Skull without temporal vacuities. 

 Compact body enclosed in a case, consisting of bone and horny 

 plates, which form a dorsal carapace and a ventral plastron. The 

 vertebrates and ribs of the thoracic region fuse into the carapace, 

 and the pectoral and pelvic girdles are internal to the ribs. The 

 limbs terminate in claws, or are flipperlike. There are no teeth and 

 the quadrate bones are immovable. The cloaca is elongated. 



This order includes tortoises, which are strictly terrestrial; 

 turtles y semi-aquatic and marine; and terrapins y which are hard- 

 shelled fresh water species. 



Fig. 163. Atlantic green turtle. (Courtesy of N. Y. Zool. Soc.) 



The green turtle ( Chelone mydas) is a marine form, reaching a 

 weight of 400 pounds, whose flesh, oil and eggs are all consumed by 

 South Americans. In this country, soup and flesh are esteemed 

 delicacies. The hawks-bill turtle {Chelonia imbricatd) is a smaller 

 marine form once used as a source of tortoise-shell, but now little 

 sought. The leathery turtle {Sphargis coriaced) is the largest living 

 turtle, reaching a weight of 1,000 pounds and a length of six feet. 

 It is marine, but spawns on land. It is inedible. The giant tortoise 

 {Testudo) ot the Galapagos Islands is a gentle form, frequently 

 photographed at zoos carrying children on its back. It may reach 

 a weight of 300 pounds. The common snapping turtle {Chelydra 



