LIMNOHTUS. 707 



plete interior basal cingulum. The third premolar is as wide as the fourth, 

 and about as large as the corresponding tooth in P. major, but different from 

 it in the absence of tubercle and ridge that mark its external face. The 

 first premolar has two roots, and the canine is large and stout. 



Measurements. 



u. 



Length of entire molar series 0. 1740 



Length of true molars 1060 



Length of last molar (crown) 0420 



Width of last molar (crown).. 0473 



Length second molar 0350 



Length fourth premolar 0260 



Width fourth premolar 0260 



Width third premolar 0200 



Length third premolar 0200 



Diameter of basis of canine 0263 



The L. j)ahidosus Leidy is similar to this species in the rugosity oi 

 the enamel of its teeth, but appears by the measurements to be distinctly 

 smaller. My expedition did not obtain any specimens which I can as yet 

 certainly refer to this species. The measurements given by Professor Marsh 

 for his PaloEOsyops {Lymnohyiis) laticeps approaches very nearly to this one 

 Thus the width of the crown of the penultimate superior molar in L. palu- 

 dosus is M. .C38; in L. laticeps, .036; in L. diaconus Cope it is .042. 



In comparison with Marsh's description of his P. laticeps, the measure- 

 ments are all larger, and the enamel is as rugose as in L. major, instead of 

 smooth. The shortening of the premolar series is the same in the two spe- 

 cies; thus, in P. laticeps the two sets of molars are related as 94°"° to 61; 

 in the present one, as 106: 68. 



From Henry's Fork of Green River. 



LlMNOHYUS FONTINALIS Cope. 



Palocosjjops foniinaUs Cope, Pal.'eontological Bulletin, No. 11, p. 1, Jan. 31, 1873. Proceedings American 

 Philosophical Society, 1873, p. 35. Limnohyus fontinaUs Cope, Annual Report U. S. Geol. Survey 

 of the Territories, 1872 ri873), p. 594. 



Plate XLIX, fig. 9; Plate L, fig. 4; and Plate LVUIa, figs. 4-6. 



This chalicotheroid is represented in my collection by a considerable 

 part of the skull of one individual. This includes the greater part of the 

 occipital and parietal bones, with the right squamosal almost entire; the 

 right maxillary and malar as far forwards as the fourth premolar tooth ; and 



