372 BULLETIN UNITED STATES GEOLOGICAL SURVEY. \Tol.n. 



tlie measurements. There is one inflection of the sheathing enamel on 

 each side of the crown in all the molars in their present state of wear. 

 The positions of the lakes indicate that in an earlier stage there were 

 two external inflections. At present all the molars display a fossette 

 external to the fundus of the internal inflection. Besides this there are 

 two others in the first molar, and one other in the fourth. Posterior to 

 the external inflection there is one fossette in the first and third molars, 

 two on the fourth, and none on the second, where it is probably worn 

 out. According to Leidy there are three in this position in all the mo- 

 lars in the C. nehrascensis, and two in the position first described. Ac- 

 cording to Filhol, there is but one in each position, in about the same 

 stage of weat, in the C. viciacensis. 



The inferior molars display a deep external inflection, and three trans- 

 verse lobes on the inner side. These probably represent inflections at 

 an earlier stage of wear; the median one is still continuous with the 

 sheathing enamel on the first molar (Pm. IV). The sizes of the inferior 

 molars increase anteriorly regularly, excepting that the first is relatively 

 a little longer than the others. 



Measurements of shull. 



M. 



Leugth from inion to edge of nasals 067 



Length from edge of nasals to interorbital constriction 034 



Length of mnzzle to preorbital angle of maxillary 018 



"Width of skull at paroccipitals 025 



Width of skull at posterior edge of squamosal 034 



"Width at zygomata posteriorly 056 



Width at iuterorbital constriction 006 



Width between anterior parts of orbits 0275 



Width at base of muzzle 018 



Leugth from occipital condyle to front of otic bulla, inclusive .018 



Leugth from bulla to last molar tooth 008 



Length from first molar to base of incisor 023 



Length of superior molar series 0195 



Diameters of first molar J ^^t^^^oP^^t^^^^^ 00^5 



( transverse 0045 



Diameters of fourth ^lolar j ^^*«^«PO«t«^io^ 0030 



( transverse 0035 



Measurements of mandible. 



Length from condyle to incisor tooth 0390 



Length from incisor to Pm. IV 0105 



Leugth of inferior molar series 0145 



Diameters of Pm. IV ^^^*^^'*^P°^*«™^ 0047 



transverse 0040 



Diameters of M. I ^ ^^t^^^P^^^^""^ 0030 



transverse 0040 



Diameters of M. IV < 



anteroposterior 0030 



transverse 0035 



Depth of ramus at diastema 0100 



Depth oframusat Pm. IV .0130 



Depth of ramus at M. Ill 0100 



