GEOLOGICAL SURVEY OF THE TEREITORIES. 629 



The vertebrals are snbquadrate in form. N^eitber carapace nor plas- 

 tron is tbick. Tbe mesosternal is transverse, diamoud-sbaped, and an- 

 gular in front. 



Measurements. 



M. 



Lea<5tli 023 



Width 034 



From tbe Green Eiver beds at Black Buttes. A tbird but uncbarac- 

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

 ceous, i)robably belong to tbis species. 



Emys pachylomus, Cope, sp. nov. 



Established on fragmentary specimens of a species similar in size to 

 tbe last. The principal difference is to be seen in tbe scutal sutures, 

 "wbicb, tbougb strongly marked, are not so widely and deeply impressed, 

 Tbougb tbey are fine, tbey interrupt the dorsal carina, wbicb swells up 

 from it, and divides tbe flat proximal portion from the mucb swollen 

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

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

 in front, and bears part of tbe gular scuta. 



From Green Eiver beds, near Black Buttes. 



Emys terresteis, Cope. 



FalcBotTieca terrestris, Cope. Proceed. Amer. PMlos. Soc, 1872, p. 464. 



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

 scuta, wbicb only reach the apex of the mesosternal. - In neither are the 

 articulations of the bridge with tbe costals known. Represented by 

 three individuals, one of which may be regarded as tbe type. Tbey are 

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

 Aromoclielys odoratus of our ponds. 



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

 by a deep sutural groove, which is less pit-like than the E. polycyphus. 

 Tbe bone itself is broader than long, being, perhaps, from the binder part 

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

 characterized by tbe considerable and abrupt projection of that part 

 inclosed b^^ 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 mucb 

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



Measurements. 



M. 



Length vertebral bone 009 



Width vertebral bone 013 



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 plastron, as in tbe species of Notomorplia. In it tbe 

 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 third 

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



