GEOLOGICAL SURVEY OF THE TERRITORIES. 629 



The vertebrals are subqiiadrate in form. Neither carapace nor plas- 

 tron is thick. The mesosternal is transverse, diamoud-sliaped, and an- 

 gular in front. 



Ileasurements. 



M. 



Length 0-J3 



Width 0\'A 



From the Green Eiver beds at Black Buttes. A third bnt uncliarac- 

 teristic series of fragments, from the first lignite-bed above the Creta- 

 ceous, i)robably belong to this species. 



Emys pachylomus, Cope, sp. nov. 



Established on fragmentary specimens of a species similar in size to 

 the last. Tiie principal diflereiice is to be seen in the scatal sutures, 

 which, though strongly marked, are not so vridely and deeply impressed. 

 Though they are fine, they interruj^t the dorsal carina, which swells up 

 from it, and divides the fiat proximal portion from the much swollen 

 marginal part of the marginal bones. The mesosternal bone is similar 

 in form to that of the last species ; the only specimen is obtusely rounded 

 in front, ami bears part of the gular scuta. 



From Green Eiver beds, near Black Buttes. 



Emys terrestris. Cope. 



PalaotJieca terrestris, Cope. Proceed. Amer. Philos. Soc, 1872, p. 464. 



In this species, and the following, the lip only is inclosed by the gular 

 scuta, which only reach the apex of the mesosternal. In neither are tiie 

 articulations of the bridge with the costals known. Represented by 

 three individuals, one of which may be regarded as the type. They are 

 all thinner than the E. polycyphus, and larger, being about equal to the 

 Aromoclielys odoratus of our ponds. 



' In the type specimen the carina of the vertebral bones is interrupted 

 by a deep sutural groove, which is less pit-like thau the E. poIyci/pJuis. 

 The bone itself is broader than long, being, perhaps, from the hinder part 

 of the carapace. The clavicular (episternal) bone is preserved. It is 

 characterized by the considerable and abrupt projection of that part 

 inclosed by the gular scutum, which resembles what is sometimes seen 

 in Testudo. The edge of this part is entire and -acute. The posterior 

 part of the projection forms a step-like prominence behind, on the supe- 

 rior or inner face. The bone is almost as wide as long, and the meso- 

 sternal causes a very slight medium truncation, but overlapped much 

 on the inner side. The gular dermal suture does not reach it. 



Measurements. 



Length vertebral bone (109 



Width vertebi'al bone 01^ 



Length episternal 02 



Width episternal, (transverse to axis of body) 017 



Width of a costal Oil 



Thickness proximally 003 



In the second specimen, a strong groove is seen to bound the lip of 

 the front lobe of the ifiastron, as in the species of JSfot^nwrpha. In it the 

 marginal is seen to be stout, a little recurved, and sharp-edged. A ver- 

 tebral differs from those described in being longer than wide. In a thud 

 individual, the gular lip is not so prominent as in the type, and the itie- 



