EEPTILIA. 327 



Uylceosaurus Mantell. Resembled the lizards moi-e than the 

 crocodiles iu the deutal characters. Vertebrae slightly biconcave. 

 Wealden. 



Sp. Uylceosaurus armatus Mant. 

 Iguanodon Cuv. Teeth resembling in shape those of Iguana. 



Sp. Iguanodon MantelU Cuv. Vertebras either flat or slightly biconcave. 

 Probable total length twenty-eight feet. Wealden. See Phil. Trans. 1825, 

 PI. 14, Cuv. Oss. foss. V. 2, PI. 2 1, figs. 28—33. 



Clielonii. 

 Foot-prints of land tortoises have been discovered in the New 

 Red Sandstone, and impressions of parts of the shield in the Jura 

 Limestone and Stonesfield Oolite. Ossified remains of extinct genera 

 have been found in the tertiary divisions and the diluvial. 

 Amongst the last are portions of the shield of Colossochelys of Caut- 

 LEY and Falconer, indicating an animal of 18 — 20 feet long, found 

 in the diluvium of the Himalayas. {Proceed. Zool. Soc. 1844, p. 501.) 

 Extinct Emydians have been found in strata as early as the 

 Jurassic group and Wealden ; Trionychians in the Lias, Eocene, 

 &c., and turtles in the Portland stone, Wealden, Chalk, &c. 



For the extinct genera and species of Chelonians, see Cuv. Ossevi. 

 foss. V. 2, pp. 221 — 249, and the memoirs of Owen, cited p. 321.] 



