44 



is perfectly smooth. The distal portion of the dentary boue is toothless ; 

 its anterior tooth is a fang with base excavated in front ; and an angle 

 rising from the external side of it becomes a latero-exterior cutting edge 

 of the crown to the apex. The inner i)osterior, or more convex face, of 

 the tooth is regularly and closely striate-grooved. On one dentary there 

 are three or four small denticles in front of it on the outer side. The 

 smaller teeth have two cutting edges, and the posterior face at the base 

 is grooved striate. This regular grooving, as well as the large size of 

 the first maxillary, distinguishes this fish from theEnchochis anceps. 



Measurements. 



M. 



Length of preinaxiilary bone above 0. 075 



Depth of premaxillary 033 



Width of basis first maxillary tooth 010 



Length of dentary at first tooth 020 



Length of dentary to first tooth 020 



Length of first tooth : - 032 



Interval between maxillary teeth 008 



Mobrara epoch of Phillips County, Kansas ; discovered by Prof, B. F. 

 Mudge. 



E^^CHODUS, Agass. 



Enchodus peteosus, SI), nov. 



Established on the maxillary a^nd premaxillary bones, of both sides 

 of the sameiudividual. In the latter bone the anterior margin is truncate 

 obliquely upward and backward, its lower margin passing into the base 

 of the single large tooth ; alveolar surface elongate, posteriorly narrowed 

 to an obtuse edge. The maxillary exhibits both borders obliquely 

 truncate, with sutural face. The alveolar aspect supports two teeth, one 

 larger than the other. 



The premaxillaries are very massive, and exhibit on their upper faces 

 three oblique fosspe, the posterior transversely subdivided. External 

 face smooth. 



Measurements. 



M. 



Length of premaxillary, (distal end lost) 0.067 



Greatest width of alveolar face 018 



Depth of outer face 030 



Diameter at basis of tooth 009 



Obtained by Professor Mudge from beds of the Kiobrara epoch in 

 Kansas. 



Enchodus (?) anceps. Cope; Cimolichlhys anoeps, Cope, Proceed. Amer. 

 Philos. Society, 1872, 552. 



Mobrara epoch of the Smoky Hill River. 



Enchodus calliodon, Cope, loc. cit, 354. 

 Mobrara epoch of the Smoky Hill Eiver. 



Enchodus shumardii, Leidy, Proceed. Acad. ISTat. Sciences Phila- 

 delphia, 185G, 257; Report tl. S. Geol. Survey Terrs., I, 1873, 287, 

 tab. xvii, fig. 20 Sage Creek, Dakota. 



