.No. 8.] COPE ON EOCENE VERTEBRATA OF WIND RIVER. 193 



size than any of the Leptictidce hitherto known. The general form of the 

 inferior true molars is a good deal like that of StypJiolophus, but they 

 may be distinguished by three characters in which they at the same 

 time, agree with the Ictops Mcuspis : First, the elevated border of the 

 heel, with a strong external cusp and weaker posterior and internal ele- 

 vations ; second, the small development of the anterior cusp ; third, the 

 posterior production of the heel of the third true molar, giving an indica- 

 tion of a fifth lobe. The external anterior cusp of the third molar is ele- 

 vated ; on the first molar it is less so, and the anterior cusp is small. The 

 enamel is smooth, and there are no internal nor external cingula. The 

 mandibular ramus is compressed and deep. 



Measureme7its. 



M. 



Length of bases of three true molars 0165 



T,. , J? ^ . J. 1 (anteroposterior... 0055 



Diameters of first true molar < , ^ , , . n ^r^or, 



( transverse benmu 0038 



^. ^ ^ ,' i , , c anteroposterior 0060 



Diameters of last true molar < , „„_„ 



C transverse 0050 



Depth of ramus at anterior root of last true molar 0095 



The jaw fragment described indicates a skull about the size of that of 

 the common opossum. 



30. Protopsalis TiaRiNUS Cope. 



American Naturalist, 1880, p. 745. 



Char. gen. — Probably Oxycenidce* but as the type species is only 

 known from two true molars and a canine of the inferior series, with 

 bones of the skeleton, this point remains to be ascertained. Femur 

 with a weak third trochanter. Inferior molars : one like those of Oxy, 

 cena^ i. e., with large heel and internal cusp ; another, probably the last- 

 larger, without internal tubercle, and with a rudimental heel, thus re- 

 sembling the inferior sectorial of various existing Carnivora. 



Char, specif. — Size about that of the tiger or jaguar, exceeding that of 

 any other flesh-eater of the Wasatch epoch. The heel of the smaller 

 tubercular-sectorial is not large, and has a piano- concave superior sur- 

 face. The principal cusp is much elevated, while the internal cusp is 

 small. The sectorial differs from that of a Hycena in having the poste- 

 rior cusp more, and the anterior cusp less elevated ; the heel is only a 

 strong iDosterior cingulum, which is continued as a narrow line along 

 the inner base of the tooth. A rough cutting ridge forms the poste- 

 rior inner angle of the principal cusp. There is a wide longitudinal 

 groove of the inner face of the inferior canine, whose enamel surface is 

 impressed-punctate. The shaft of the femur is nearly straight. Diam- 

 eters of crown of sectorial, anteroposterior, .025 ; transverse, .014 ; ver- 

 tical, .022 5 length of heel of tubercular-sectorial, .006 ; width of same, 

 .006; vertical diameter of base of crown of canine, .022 j depth of 

 mandible at last molar, .014 ; length of femur (condyles inferential), 

 .300 ; diameter of shaft at middle, .034. 



* See Proceed. Amer. Philos. Soc. 1880, July. 

 13 GB 



