142 THE WASATCH AND BRIDGER FAUN^. 



DERMATEMYS Gray. 



Annals Mag. Nat. His., 1847, p. 60. Catal. Shield Reptiles British Musonm, 1855, p. 49. Baptcmy 

 Leidy, Proceed. Acad. Phila., 1670, p. 4. Report U. S. Geol. Surv. Terra., i, 173, p. 157. 



This genus is similar to Emys in the structure of the carapace and 

 plastron, except that the lobes of the latter are narrowed and shortened. 

 The scuta are similar, excepting that there is a series of intermarginals on 

 the bridge on each side. There are thirteen marginals on each side, those 

 of the last pair in contact throughout. In a specimen of the extinct species 

 of the Bridger, I tind a trace of an intergular scute, as is sometimes seen in 

 D. berarcU now living in Mexico. 



Dermatemys vyomingensis Leidy. 



Baplemyi icyomtnjwtsi*, Report of the United Statos Geological Sun-ey of Territories, i, 1873, p. 157. 



Plates xii, and xv fig. C. 



This tortoise is not uncommon in the Bridger beds, but generally in a 



dislocated or fragmentary condition. It is readily distinguished as a species 



by the elevated keel of the posterior vertebral and pygal bones. The 



mesosternal is large and emydiform, and is not marked by the humero-pec- 



toral dermal suture. It is extensively occupied by the large gular scuta, 



which exceed in size those of any other species of the formation. The 



size rather exceeds that of the average Emys vyomingensis. The Wasatch 



species D. costilatus* Cope diflPers in having an obtuse keel on the costal 



bones, parallel with the median line of the carapace, as in Staurotypus tri- 



porcatm. 



NOTOMORPHA Cope. 



Proceedings of the American Philosophical Society, 1872, p. 474. 



This genus reposes on a clavicular or episternal bone, which gives 

 characters not seen in any other genus known to me. The sutures are dis- 

 tinct and fine, and the form of the mesosternum is emydoid. The gular 

 scuta are small, and occupy an angular space between the large intergular 

 and humeral, which are extensively in contact. It is uncertain whether 

 there are two or only one intergular. The general characters of the other 



•H<^port Expl. and Siarv. \\ . 100th Mer., (J. M. Wh(-«ler, iv, pt. ii, p. b1. 



