5 



M. 



Width just below neck 017 



" at middle Oil 



" " extremity 019 



" of trochlea 009 



Longest chord of condyles and trochlea 019 



The remains of this species were found together by the writer in the 

 Bridger beds on Black's Fork, Wyoming. 



ANAPTOMORPHUS. Cope. 



Proceedings of the American Philosophical Society, 1872, p. 554. - 

 This genus is represented by the left ramus mandibuli of a single 

 species. The posterior portion is broken away, and the teeth remaining 

 perfect are the P. M. 2, and M. 1 and 2. The ramus, though small, is 

 stout, and deeper at the symphysis than at the last molar. What appears 

 to be the dental foramen is nearly opposite the bases of the crowns of the 

 molars. The mental foramen issues beneath the first premolar. 



Dentition of the ramus mandibuli, In. 2, C. 1, P.M. 2, M. 3, total, 16. 

 It differs in many respects from these ; there is no interruption in 

 the series near the canine, and the symphysis, though massive, is not 

 coossified. Further details are, the last molar is three-lobed and 

 elongated behind. The composition of the crowns of the preceding 

 molars consists of four opposed lobes, which are very stout, and con- 

 nected transversely by a thin ridge behind, or in close contact in front. 

 The premolar tooth which is best preserved, is a perfect second, which, 

 while having two roots, possesses a crown which stands almost entirely 

 on the anterior, presenting a curved sectorial crest forwards and up- 

 wards. 



The dentition is more decidedly quadrumanous in this genus than in 

 the last, and it might be referred decidedly to Lemuridcv were it not for 

 the unossified symphysis. It no doubt represents a distinct group or 

 family from Tomitherium,, and one more nearly related to the existing 

 types of Madagascar and South Africa. 



Anaptomorphus ^emulus. Cope, loc. cit. 



This species was about as large as a marmoset or a red squirrel. The 

 enamel of the teeth is entirely smooth. 



Measurements. 



M. 



Length dental line 0.0148 



" of last molar 0030 



" " ante-penult 0025 



Width " « 0020 



Length of three molars preserved 0070 



From the Bridger Beds of the upper valley of Green River. 



