THE FORE FOOT OF DIMETRODON 



3^-3 



position in the carpus and is much larger than the second. Centrale 

 2 lies between the ulnare and the third, fourth, and fifth carpals, but 

 is surrounded by bones, as its outer side articulates with the sesamoid. 

 The form and articulation of the five carpals of the distal row are best 



Fig. I. — Lower side of the manus of the right foot of Dimetrodon ^p. r', radiale; 

 u', ulnare; i, intermedium; c i, centrale one; c 2, centrale two; s, sesamoid; i, 2, 3, 4, 5, 

 carpals and metacarpals. Natural size. 



seen from the figure. The fifth carpal is peculiar in its prominent 

 position at the side of the carpus, standing well away from the rest of 

 the bones. 



A second specimen of Dimetrodon discovered the same summer 

 aft'orded a nearly complete anterior portion of the skeleton. It has 

 received the number looi in the Chicago collection. The bones of 



