THE BIG-HEADED TORTOISE 



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the cup behind and the ball in front, whereas in the tortoise family just the reverse 

 of this arrangement occurs. On the other hand, the carapace resembles that of the 

 latter, and differs from that of the snappers in the absence of a rib-like process from 

 its posterior angles passing backward beneath the marginal bones. The carapace is 

 characterized by its extreme depression and oval form, while the plastron is of mod- 

 erate size, and connected with the carapace solely by a ligament, so that bony but- 

 tresses are totally lacking. The head is covered with a continuous horny shield, 



THE BIG-HEADED TORTOISE. 

 (One-half natural size.) 



and the hooked jaws are of great pow r er. The toes are of moderate length, and but 

 slightly webbed; all, save the fifth in the hind-foot, being furnished with claws. 

 The long and cylindrical tail becomes compressed at the end, and is covered with 

 rings of quadrangular shields. In size this tortoise is small, the length of the cara- 

 pace being only about six inches, and that of the tail some three-quarters of an inch 

 more. In the adult the color is olive brown above, and yellowish brown beneath, 

 but the young is more brilliantly colored. Of the habits and mode of life of this 

 tortoise, nothing appears hitherto to have been ascertained. 

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