the Marsh Collection, etc. 439 



and hypoconid. The entoconid is represented simply by 

 a ridge. 



An unworn Mj, Cat. No. 12841, Y. P. XL, collected on 

 the Niobrara River, near the month of Minnechadnza 



Creek, exhibits nearly the same characters, except that 

 the entoconid is composed of two small marginal cusps 

 as in Leptocyon and the metaconid is a little smaller. 



In size this species is probably about the same as the 

 grizzly bear (Ursus h or rib His). 



Measure mods. 



10010 18258* 



Y. P. M. A.M.N.H. 



mm. mm. 



P 3 . ant. post, diameter 15 



P 4 . aiit.-post. diameter 19.5 



P 4 . transverse diameter 10 



M,. ant. -post, diameter 35.5 35 



M 13 transverse diameter 17 17.3 



M 23 ant. -post, diameter 23 "25.1 



M^, transverse diameter 16 17.6 



Depth of ramus below middle of Mj 52 57.3 



Length of inferior tooth row, P 3 -M 2 , inel 91 92.8 



* The author is indebted to Doctor W. D. Matthew for his kindness in 

 sending these measurements to him. 



Mluro&on suvns (Leidy). 



A left lower jaw with milk premolars, Cat. Xo. 12817, 

 Y. P. M., is identified with this species. The first true 

 molar was not erupted, but the external mandibular wall 

 has been removed, thus exposing- this tooth. The three 

 deciduous premolars are similar in the main characters 

 to those of Canis. The details of the crown of the fourth 

 premolar closely resemble that of the permanent first 

 lower molar, except in regard to size. All of the pre- 

 molars are two-rooted. 



JElurodon near wheelerianus (Cope). 



Cat. Xo. 10060, Y. P. M., consists of part of a left ramus 

 with P., and P 3 and part of M 5 and M 2 with the canine, 

 the alveolus of P x and part of that of I :; , together with 

 a part of the maxilla bearing P 4 and M 1 , and two loose 

 teeth. It was collected on the Niobrara River, Nebraska. 



The upper carnassial possesses a stout anterior tubercle 



