MESOZOIC TIME — CKETACEOUS. 



849 



pies. Two Lizards, Chamops segnis Marsh, and Iguanavus teres Marsh. (1892), 

 occur in Wyoming in the beds affording the Ceratops remains. 



1418 



1418-1421. 

 1419 



1420 



i H 



i \ 



1421 



MosASATTEiDS. — Fig. 1418, tooth, of Mosasaurus princeps (xj); 1419, snout of Tylosaurus micromus, showing 

 bases of four teeth (xj); 1420, right paddle of Lestosaurus simus (XjJj); 1421, restored jaw of Edestosaurus 

 dispar (x|). AU from Marsh. 



The Turtles (or Chelonians of the American Cretaceous) were of 50 or 

 more species ; and one, Protostega gigas of Cope (?Atlantochelys Mortoni Agas- 



1422. 



Fig. 1422, Pteranodon longlceps, head (x^) : a, upper view ; 6, side view. Marsh. 



siz), from the Niobrara beds of western Kansas, had a head two feet long, 

 and a total length of nearly 13 feet. Desmatochelys Loivii of Williston is 



DANA'S MANUAL, — 54 



