612 ' GEOLOGICAL SURVEY OF THE TERRITORIES. 



the opposite angle nearly riglit and the two remaining sides flat. The 

 crown is divided into three elevated trihedral cones, one at each angle. 

 Their adjacent angles are acute, and the angle of union is fissured like 

 the same i)oint in the sectional tooth of carnivora. The smaller lobes 

 are of equal elevation, but the crown of one is expanded so as to be 

 slightly spade-shaped. The enamel is smooth. 



Measurements. 



Elevation of bigliest cusp 0.009 



Elevtjtion of shorter 007 



Loug diameter base of crowu , 000 



Loug diameter base of fiat side 005 



The premolar is smaller, with shorter cusps, and one of the laterals 

 reduced to a ru<liment. This species is near T.faUax of- Marsh, but the 

 tooth he describes is narrower in proportion to its length, and has the 

 anterior lobe little over half as high. The measurements of this species 

 are somewhat larger than those given by Marsh for his T. grandis, 

 (Amer. Jouru. Sci. Arts, xVugust 13, 1872.) 



EEPTILIA. 

 CROOODIL. 



CROCODILUS. 



Crocodilus clavis. Cope. 



Proceed. Amer. Philos. Soc, 187:2, p. 485, (Aug. 20.) 



This is a large species, with a muzzle of narrowed proportions, and 

 suflicient depth to give it a broad oval section. The nasal boues appear 

 to have reached the nasal orifice. The anterior superior teeth are very 

 large, especially the canine. The inferior tooth corresponding is large, 

 and occupies an emargination which approaches near to the nasal 

 suture. The pitting of the muzzle is fine, and the swollen interspaces 

 much th^ wider. The teeth have stout conic crowns, with well-devel- 

 oped cutting edges, and coarse striate sculpture. The mandible is 

 acuminate to the narrow extremity, and has a long symphysis, which 

 extends to opposite the third tooth behind the notch. The cervical 

 vertebrae preserved have round cups ; they have a« simjile elongate 

 hypopophysis, with a pit behind it; shoulder very prominent. 



Measnremeiits. 



M. 



Length of ramus, with teeth ■ 



LcDgth of symphysis 135 



Width of ramus at end of symphysis 085 



Width of ramus at end of maudiljle O'iO 



Width of maxillary at third tooth above 020 



Width of maxillary at notch above 020 



This species has a more vslender muzzle than those described by Marsh 

 and Leidy, and is of larger size. 



Oeocodilus elliottii, Leidy. 



Geological Survey Montana, 1871, p. 366. 



Abundant in the Bad Lands. 



CROCODILUS SULCIFERUS, Cope. 



Proceedings American Philosophical Society, 1872, p. 555, (October 12.) 

 A medium-sized species with cranium deeply and roughly pitted. 

 The chief character is at present visible in the teeth. The larger of 



