CEEODONTA. 299 



M. 



Length of mandible with condyle 109 



Elevation at coronoid process — 052 



Elevation of condyle 027 



Elevation at last molar 021 



Elevation at first premolar 013 



Thickness at first tnie molar 008 



Length of molars from canine 059 



Depth of ulna at middle 010 



Anteroposterior width of distal end of fibnla, with process 012 



The Stypolophus tvJiitice is dedicated to Frances Emily White, M. D., the 

 professor of physiology in the Woman's Medical College of Pennsylvania. 



I insert here what should have been noted under the head of the sub- 

 order Creodonta; the successional modifications of the superior molar teeth 

 to be seen in the various genera of this group. In ilfioc?oE«M5-and in some 

 of the teeth of Mesonyx the extremes are to be observed, viz : In the former 

 two well-separated conic external tubercles, and in the latter but one. In 

 Deltatherium and PeratJierium these tubercles are flattened externally, and 

 directed inwards in true Didelpliold fsishion. In Didelpliodus and Stypoloplms 

 they are close together and more conic, but the angle extending from the 

 posterior cusp foreshadows a sectorial blade. In Pterodon and OxycBua this 

 blade is realized, and the two cusps are flattened and nearly fused, producing 

 a type of sectorial peculiar to the family of the Oxyoenidoe. 



Stypolophus acdleatus Cope. 



Report Capt. G. M. Wheeler, U. S. Geog. Geol. Surv W. of 100th Mer., iv, pt. ii, p. 112. Tricodon 

 aculeaius Cope, Proceed. Amer. Philos. Soc, 1872, p. 460. Paleontological Bulletin No. 1, p. 1, 

 July 29, 1872. 



Plate XXIV, figs. 6-7 ; XXVII, figs 1-2. 



This species was first described from a premolar and a true molar, 

 teeth of the inferior series. I now give a description of a considerable 

 part of the dentition of both jaws. I am enabled to do this through the 



