354 BUFFALO LAND. 



ologist. The spur was small and of soft material, and 

 we speedily removed it in blocks, to the level of the 

 reptile, and took out the remains, as they laid across 

 the base from side to side. A genus related to the 

 last is Edestosaurus. A species of thirty feet in 

 length, and of elegant proportions has been called Fj. 

 tortor (Cope.) Its slenderness of body was remark- 

 able, and the large head was long and lance-shaped. 

 Its flippers tapered elegantly, and the whole animal 

 was more of a serpent than any other of its tribe. Its 

 lithe movements brought many a fish to its knife- 

 shaped teeth, which are more efficient and numerous 

 than in any of its relatives. It was found coiled up 

 beneath a ledge of rock, with its skull lying undis- 

 turbed in the center. A species distinguished for its 

 small size and elegance is Clidastes pumilus (Marsh). 

 This little fellow was only twelve feet in length, and 

 was probably unable to avoid occasionally furnishing 

 a meal for some of the rapacious fishes which 

 abounded in the same ocean. 



Tortoises were the boatmen of the cretaceous 

 waters of the eastern coast, but none had been 

 known from the deposits of Kansas until very re- 

 cently. One species now on record {Protostega gigas, 

 Cope), is of large size, and strange enough to excite 

 the attention of naturalists. It is well known that 

 the house or boat of the tortoise or turtle is formed 

 by the expansion of the usual bones of the skeleton 

 till they meet and unite, and thus become continu- 

 ous. Thus the lower shell is formed of united ribs 

 of the breast and breast-bone, with bone deposited 

 in the skin. In the same way the roof is formed 



