Peterson: Material Discovered in Uinta Basin. 59 



which is high and latcralh' compressed, but whether or not it was cleft 

 or whether it was retractile cannot be determined. 



M EASUREMENTS. 



Tibia, approximate length ' i6o mm. 



Pes, length, calcaneum to ungual phalanx 158 " 



transverse diameter from cuboid to entocuneiform, approxi- 

 mately 33 



greatest length of calcaneum 50 



greatest height of cuboid 18 



length of Mt. 1 33 



length of Mt. Ill 48 



length of Mt. IV 56 



length of proximal phalanx digit (? IV) 30 



length of median " " (? IV) 18 



7. Pleurocyon medius sp. no v. 



In the America-n Museum collection of Uinta material are two frag- 

 mentary specimens, No. 1969, a fragment of a lower jaw with My in 

 place, and No. 1992, a lower jaw without teeth, and a number of 

 fragments of limb-bones. These pertain to a considerably smaller 

 species, which may be called Pleurocyon viedius, the second species 

 known from the Uinta formation. 



The genus as described above should undoubtedly be placed in the 

 family Miacidcc, as defined by Dr. Matthew.^^ A careful study of the 

 type makes it possible to further place the genus in Matthew's series 

 "B," the "Cercoleptoidei" of the subfamily MiacincB {I.e., p. 346). 

 In certain respects the genus is perhaps most nearly like Vnlpavus, 

 having, as that genus, low trigonids, the lower molars uniform in their 

 general characters, ^^ and decreasing in size from the first to the third. 

 However, instead of having the broad basin-like heels of the molars 

 as in Vulpaviis, the present genus has molars with long trenchant 

 heels, more like what is observed in Oodectes. From the latter the 

 present genus differs in having the posterior basal cusps of the lower 

 premolars larger and better defined, the trigonids of the molars lower, 

 and the whole animal of much larger size. The paratype presents 

 many characters common to the Miacidce which have already been 

 mentioned. 



'^"Carnivora and Insectivora of the Bridger Basin," Mem. Amer. Mus. Nat. 

 Hist., Vol. IX, 1909, pp. 344-345. 



15 M3 is unfortunately lost, but judging from the space it occupied, it was of 

 somewhat large size. 



