132 



AMERICAN MESOZOIC MAMMALIA 



Zo. 



a' 



Fig. so. Lower molars of Lance didelphids. i, Cimolesies. 2, Diaphorodon. 

 3, "type 4." 4, Del-phodon. 5, "type 5." 6, "type 6." 7, "type 7." 8, "type 8." 

 9, "type 9." 1-3, 2j4 times natural size. 4-7, four times natural size. 8-9, 

 five times natural size. 



Diaphorodon Simpson 1927 (Type 2) 

 1927. Diafhorodon, Simpson, Anier. Jour. Set. (5) XIV, 127. 



Definition. — Didelphid lower molars of relatively large size. Trigonid some- 

 what higher than talonid, compressed anteroposteriorly. Pr'' and pa<^ nearly equal, me"" 

 much reduced. Anterior cingulum broad, almost basined. Only two indefinite talonid 

 cusps in type, but this probably due to corrosion as referred specimens show the normal 

 didelphid arrangement. 



Type. — D. curtus (Marsh). 



Distribution. — Lance, Wyoming. 



This genus was necessarily erected for the reception of Cimolestes curtus Marsh 

 which is certainly not congeneric with Cimolestes incisus. Diaffwrodon is clearly re- 

 lated to Eodelfkis of the Belly River and may be a direct descendant of the latter 

 genus. 



Diaphorodon curtus (Marsh 1889) 



1889. Cimolestes curtus, Marsh, Amer. Jour. Set. (3) XXXVIII, 89. 

 1889. Didelfhodon jerox, Marsh, Amer. Jour. Set. (3) XXXVIII, 88. 

 1927. Diafhorodon curtus, Simpson, Amer. Jour. Sci. (5) XIV, 127. 



Type. — Y.P.M. No. 11774. Isolated lower molar. Fig'd, Marsh 1889A, PI. IV, 

 figs. 8- II. 



