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PROCEEDINGS OF THE NATIONAL MUSEUM 



An Ms, if properly referred, indicates this tooth to be more reduced 

 than in E. Jenvwroides and much more reduced than in E. acolytus^ 

 E. aequidens, and E. aquilonius. 



The upper cheek teeth do not closely resemble thojse in the genotype, 

 E. inaequidens. The upper teeth in the latter exhibit smooth crests 

 running to the protocone and weak or undeveloped cingula. 



Table 3. — Measurements {in millimeters) of upper teeth (U.S.N.M. No. 15190) 

 and lower teeth {U.S.N.M. No. 15121) of Ellipsodon shepherd! 



Measurement 



Anteroposterior diameter- 

 Transverse diameter 



Ma 



3.8 

 2.9 



' Greatest transverse diameter. 



ELLIPSODON? STERNBERGI" Gazin 

 Ellipsodon? sternbergi Gazin, 1939b, p. 2S4. 



A species nearly intermediate in size between Ellipsodon lemw- 

 oides and Mioclaenus turgidus is represented by several fragmentary 

 specimens from the Dragon horizon, including a jaw portion, No. 



15755, with M3 and a part of M2, 

 which was made the type of Ellip- 

 sodon stemhergi (fig. 17). Mo is 

 much larger and broader than in 

 other species of Ellipsodon- how- 

 ever, it apparently shows no cren- 

 ulation of the crest around the 

 posterointernal margin of the talo- 

 nid as seen in many, though not 

 all, of the lower dentitions of M. 

 turgidus. M3 is a little larger 

 than in Ellipsodon shepherdi and 

 somewhat more rounded, being 

 nearly oval in shape. The paraco- 

 nid is lacking on M3, with only a 

 low crest extending across the 

 front of the tooth, connecting the 

 protoconid and metaconid. Though 

 reduced, the paraconid is present 

 in all specimens of Mioclaenus tu/rgidus in which M3 was 

 observed. 



Among the specimens referred to E. stenibergl is a jaw portion, 

 No. 16339, having both Mj and M2 preserved. M, is but little larger 



Figure 17. — Ellipsodon sternbergi Gazin: 

 Portion of right ramus of mandible with 

 Ms and part of M2 (U.S.N.M. No. 

 15755), type specimen, lateral and occlu- 

 sal views, X 3, Dragon Paleocene, Utah. 



^5 Named for George F. Sternberg, In recognition of his field assistance. 



