Marsh Collection, Pedbody Museum. 211 



tritubercular, with only a moderate development of the postero- 

 internal cusp, and the cingulum is not continued forward 

 around the internal face of the crown and does not develop the 

 internal cingular cuspule seen in Omomys and Ilemiacodon. 

 The outer cusps are slightly flattened, externally, and the inter- 

 mediates are moderately developed. The enamel is much 

 wrinkled, particularly that upon the inner portion of the crown. 

 A second specimen, representing upper teeth, consists of a 

 large part of the superior maxilla containing all the molars 

 and the third and fourth premolars, figure 146. It also exhibits 

 the alveoli of the second premolar, canine, and probably two 

 incisors ; that of the first incisor is, however, very indistinct, 

 and one can not be sure that it was actually present.* In this 

 specimen the second molar is larger than either the first or 

 third, which are subequal. The postero-internal cusp is more 

 distinct in the first molar than in the second or third. The 

 premolars display single external and internal cusps, with a 

 strong postero-internal cingulum tending to the formation of 

 an additional cusp. The canine, as indicated by the size of 

 the alveolus, is larger than the outer incisor or second pre- 

 molar, and, as in the lower jaw, the teeth were implanted in a 

 continuous row. The infraorbital foramen is single and issues 

 above the anterior border of the third premolar in the same 

 relative position as in Hemiacodon. The malar did not reach 

 the lachrymal, thus leaving the maxillary a large share in the 

 anterior boundary of the orbit, which was enlarged. 



From these many resemblances to the Primates, there can 

 not apparently be any question of the affinities of the genus, 

 notwithstanding the peculiarities of the structure of the lower 

 molars. It seems to have left no modified descendants, how- 

 ever, in the existing fauna. 



Anaptomorphus cemulas Cope. 



Anaptomorphus cemulus Cope, Proc. Amer. Philos. Soc, October, 1872 

 p. 554. 



This genus and species were proposed by Cope upon the 

 greater portion of a left mandibular ramus now preserved in 

 the American Museum collection, which, as far as I am aware, is 

 the only specimen of this species known. The jaw carries the 

 first and second molars and the fourth premolar, together with 

 the alveoli for all the remaining teeth, eight in all. The 

 formula has been generally considered to be two incisors, a 



* That which leads me to suspect the presence of two incisors in the upper 

 series is the sharp inward curvature of the lower jaw near the symphysis, 

 giving a greater transverse width in this region of the mouth. There would 

 thus be a considerable gap left between the outer incisors and the median 

 line. I think there can be little doubt that this space was occupied by a cen- 

 tral pair of incisors. 



