150 



BULLETIN 16 9, UNITKD STATES NATIONAL MUSEUM 



On one specimen (9479) there is a very minute anterior cuspule, high 

 on the crown, which is only very vaguely suggested on a second speci- 

 men surely of the same species (9676). There is a low and very 

 small heel, with a minute cusp at the posteroexternal corner of the 



Figure 30.—Paromomys maturus Gidley, U.S.N.M. no. 9473, right lower jaw: a, Crown view; 6, internal 

 view. Four times natural size. (After Gidley, 1923, flg. 1.) 



Figure Zl.—Paromomys matmus Gidley, U.S.N.M. no. 9540, left upper jaw: a, Crown view; 6, external 

 view. Four times natural size. (After Gidley, 1923, fig. 2.) 



tooth, at the base of the posterior crest, from which a ridge passes 

 downward and internallj^ to the posterointernal corner. 



P3 has about the same length and height as P2 but is considerably 

 wider and more robust. The anterior crest is median near the apex 

 and turns inward below this, an accentuation of the slighter curve of 



