F. B. Loomis — Wasatch and Wind River Rodents. 125 





Sciurus 

 cafolinensis 



Paramys copei 



Sciuravus nitidus. 



Length of skull 



65 mm 



80 mm 



48 mm 



Width between 

 orbits 



20 mm 



10 mm 



gram 



Ratio 



13:4 



8: 1 



8: 1 



Crest 



none 



weak 



none 



Interval 



between lower 



incisor and 



premolar 



14mm 



15 mm 



nram 



Masseter 



muscle ends 



under 



intervalbetween 

 premolar 4 

 and molar 1 



intervalbetween 



molar 2 and 



molar 3 



interval between 



molar 2 and 



molar 3 



Infraorbital 

 foramen 



narrow and high 

 considerably in 

 front of pre- 

 molar 3 



oval and wide 

 nearly over 

 premolar 3 



oval and wide 

 nearly over 

 premolar 3 



Upper molars 



3 cusps 

 parastyle 



3 cusps with 

 trace of hypo- 

 cone, parastyle 



58 mm longx 15 

 wide distally 



4 cusps, no 

 parastyle 



Humerus 



60 mm long x 8 

 wide distally 





Ulna 



61 mm long 

 slender 



38 mm long 

 heavy 





Metacarpalic 



38 ram long 

 51 mm i ong 



28 mm long 





Pelvis 



71 mm long 







60 mm longx 13 

 wide at head 



, ._.. \/ i n 





Femur 



wide at head 





Calcaneum 



23 mm longx 9 

 wide 



19 mm longx 

 10 m wide 





Astragulus 



ll mm longx 5 



wide, head 



straight 



12 mm longx 8 



wide, head 



oblique 





partly merged into the ridge from the metacone. The tiny 

 mesostyle is simple. The lower molars are characterized by 

 the cusps being rather low and entirely marginal, leaving a 



Am. Jour. Sci. — Fourth Series, Vol. XXIII, No. 134.— February, 1907. 

 9 



