626 GEOLOGICAL SUEVEY OF THE TERRITORIES. 



of the middle front. The posterior lobe is somewhat flared and has a 

 wide beveled margin, and is deeply notched behind, the notch being 

 close and the lobes projecting. 



The surface is delicately sculptured with obsolete ridged lines across 

 the axis of the costal bones. The vertebral region is somewhat swollen 

 between the cross-sutures, which present an obtuse angle in the same 

 direction, both before and behind. The scuta are longer than wide, and 

 have bracket-shaped outlines. The surface has the obsolete ridges, 

 which diverge in every direction from the median inlooking angle of 

 one end, but are mostly longitudinal. 



In old specimens this delicate sculj^ture might become obsolete. 



Measuretnents. 



M. 



Length of plastron 0. 325 



Width of, at grain 150 



Wiclthlip 054 



Length lip 030 



Width clavicular hone behind 041 



Width niesosterual externally 058 



Length mesosternal externally 045 



Thickness hyosternal behind 015 



Length of vertebral scutum 072 



Width of vertebral scutum .- 068 



Width of a costal bone 029 



Thickness of a costal bone .006 



Found in the Bad Lands of South Bitter Creek by the writer. 

 Emys latilabiatus. Cope. 



Proceedings Amer. Philos. Soc, 1872, p. 471. 



Eepresented by a perfect specimen of a tortoise of a broadly oval 

 form, and somewhat terrestrial habit. Its prominent characters are to 

 be seen in the plastron, of which the posterior lobe is deeply bifurcate. 

 The anterior lobe is peculiar in the unusual width of the lip-like pro- 

 jection of the clavicular ("episternal") bone, which is twice as wide as 

 m E. vyomingensis, and not prominent. Bones all smooth ; margins of 

 lobes of plastron thickened. 



There are three scars, perhaps of muscular insertions near the poste- 

 rior margin of the plastron, one oval one opposite to each lobe, and one 

 round one opposite to the notch. 



As compared with JE. septarius this species has no such septa nor 

 sculptnre; the emargination of the plastron is more oi)en, and the lip 

 much shorter and wider. 



Measurements. 



M. 



Length of carapace 0. 255 



Width of carapace 250 



Width of lip of plastron 06 



Depth of posterior notch 02 



From near Black's Fork of Green Eivcr. 



Emys wyomingensis, Leidy. 



Geological Survey Montana, 1871, p. 367. 



Abundant in the Bridger formation. 



Emys gravis, Cope. 



Notomorpha gravis and N. garmanii, Cope, Proceed. Amer. Philos. Soc, 1872, p. 476, 477. 



The preceding names were used to designate what were supposed to 



