PALEOCENE MAMMALS OF CENTRAL UTAH — GAZIN 



47 



Anisonchus onostus is distinctly smaller than A. dvacus^ being 

 very near the Pucrco form, A. gilUanus^ in size but with the cusps 

 on the talonid of both Mi and M, slightly more widely spaced, though 

 having the cut characterizing the anisonchines. This spacing of 

 the cusps gives the teeth a wider 

 appearance, whereas actually they 

 are a trifle narrower than those in 

 several specimens of ^1. gUlianus with 

 which comparisons were made. The 

 teeth also appear somewhat lower 

 crowned than those of A. gilUarms 

 exhibiting about the same wear. 



The anteroposterior diameters of 

 the first and second lower molars 

 are 4.3 and 4,1 mm., respectively. 

 The transverse diameters are 2,9 and 

 3.2 mm. 



ANISONCHUS OLIGISTUS.»' new species 



Type. — Left maxillary j^ortion 

 with M^ and M- associated portion 

 of left ramus of mandible with Mi 

 and Mo, U,S,N.M. No. 1C192. 



Horizon and locality. — Wagonroad 

 Emery County, Utah. 



Figure 26. — Anisonchus onostus Gazin: 

 Portion of left ramus of mandible 

 with M1-M2 (U.S.N.M. No. 15788), 

 type specimen, lateral and occlusal 

 views, X 3, Dragon Paleocene, Utah, 



Paleocene, Dragon Canyon, 



Figure 27, — Anisonchus oligistus, new species: Left maxillary portion with NP-M*; 

 portion of left ramus of mandible with M1-M2 (U.S.N.M. No. 16192), type specimen, 

 lateral and occlusal views, X 3, Wagonroad Paleocene, Utah. 



Speci-fiG characters. — Upper and lower molars smaller than in 

 Anisonchus giUianus and relatively' narrower transversely. Upper 



2''oXi'7ioTos, least, in allusion to size of teeth. 



