PLATE 48 



ULNO-RADIUS OF MERYCHIPPUS SEJUNCTUS, M. PANIENSIS, M. SPHENODUS. 

 COMPARISON OF FOREARM BONES IN THREE SPECIES FROM THE PAWNEE CREEK BEDS OF NORTHEASTERN COLORADO. 



All figures one-half natural size. 



Anterior and external views. Shaft of ulna coossified more than in species of the Sheep Creek and Mascall beds, but 

 with distinct traces of separation in distal portion. 



Pawnee Creek, Col. Middle Miocene 1. Merychippus scjunctus Cope, referred specimen, Am. Mus. 9378. Asso- 

 ciated with lower jaws and large part of skeleton, a, Anterior and, b, 

 external views. 



" 2. M. panicnsis Cope, referred specimen, Am. Mus. 9382. Associated with 



skull, jaws, and large part of skeleton. Same views as 1. 

 " 3. M. sphenodus Cope, referred specimen, Am. Mus. 8251. Associated with 



part of skeleton. Same views as 1. 



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