Peterson: Material Discovered in Uinta Basin. 



71 



Antero-posterior diameter of P'^ 5 



P^ 5 



Transverse diameter of P^ 5 



P^ 5 



Antero-posterior diameter of " 5 



Transverse . 



Antero-posterior 



M' 



M^ 



M' 



5-5 

 6 



6.5 

 6 



5-5 

 6 



Transverse 



Vertical diameter of mandibular ramus at P3 9 



Vertical diameter of mandibular ramus at M3 12 



Antero-posterior diameter of inferior premolar series 



Antero-posterior diameter of inferior molar series 19 



5. 5 mm. 

 6.5 " 

 7- " 

 6 



5-5 " 



20 

 18 



For other measurements see text-figures 8 and 9, and PI. xxxvi, figs. 

 5,6. 



Genus Sphenomeryx gen. nov. 



16. Sphenomeryx quadricupsis gen. et sp. nov. (Plate XXXVII, 

 Figs. 15-16). 



Type: Fragments of upper and lower jaws with teeth, C. M. No. 

 2346. 



Paratypes: Surface fragments of two or three individuals found 

 together, representing brain-casts and other mutilated parts of limb- 

 and foot-bones, together with a fragment of a lower jaw with P- and 

 the molars represented, C. M. Nos. 2914, 2915, 2926. 



Horizon: Uinta Eocene. Base of Horizon C. 



Locality: Type found about two miles south of Kennedy's Hole to 

 the west of old Vernal- Dragon Stage- road in eastern end of Uinta 

 Basin. Paratypes found six miles east of Myton, Utah. 



Generic Characters, as shown by the Type and Paratypes: M- without 

 postero-internal tubercle, but instead a heavy ledge or cingulum, which 

 extends around the internal face of the tooth. A transverse ridge-like 

 protocone on -wear of the tooth as in Mesomeryx. Paracone conical, 

 metacone subconical. External faces of para- and metacones sharply 

 convex from side to side, as in Mesomeryx. Small parastyle, meso- 

 and metastyles absent, and instead a heavy cingulum on the external face, 

 as in Hylomeryx and Mesomeryx. Premolars heavy; deuterocone of P- 

 very small and placed well back. Lower teeth like those in Bunomeryx 

 and Hylomeryx. Animals of same size as Hylomeryx. 





