Pk TKRSON : OSTKOI.OCiV OI' C)\VliA( IVLUS. 457 



The Cuneifonit. — As \\\ Po'(-l>rot)ierii4iii the cuneiform in the co- 

 type (No. 886) is high, narrow and deep, not nearly so massive as 

 that of the llama and has a greater concavity on the proximal artic- 

 ular facet for the ulna than it has in the latter genus. The convex 

 posterior facet for the pisiform extends somewhat farther forwards, 

 especially on the radial side of the bone, thus giving a shorter oblitjue 

 facet for the distal end of the ulna than is seen in the llama. The 

 radial side is deeply excavated and has two facets, one superior and 

 one inferior, the latter much less deeply excavated than is that of the 

 llama, which fact is due to the lesser angularity of the posterior bifid 

 projection of the lunar in O. /o/ii^i/>es. The external or ulnar face of 

 the cuneiform is rounded and rugose. Distally there is a single facet, 

 concave antero-posteriorly, for articulation with the unciform. 



The Pisiform. — The pisiform (No. 886) is shorter and compara- 

 tively heavier than that of the llama. The cuneiform facet has a more 

 rounded face and equals the ulnar facet in size, while in the llama the 

 latter is somewhat larger. The free end of the bone is thicker and 

 more rugose, although not attaining the vertical depth which is seen 

 in the recent genera. The neck of the pisiform is more constricted 

 in O. longipes than in the llama. 



The T?'apezoid. — The trapezoid (No. 886) is a rounded nodular 

 bone and is proportionally not so deep as in the llama. The proximal 

 articular surface for the scaphoid is rounded much in the same manner 

 as in the recent genera. On the radial side the magnum facet is di- 

 vided, the inferior part being the larger, while in the llama the supe- 

 rior part is the larger of the two. The ulnar face is very rugose and 

 rounded and the postero-internal face carries an irregularly quadri- 

 lateral facet extending from the distal margin half way up the total 

 height of the bone and articulating with the rudimentary trapezium. 

 Distally there is one flat facet similar to that of the camel and the llama. 



The Trapeziutn. — The trapezium is a small oblong nodule greatly 

 resembling a sesamoid. There are two facets on the trapezium, one 

 antero-superior which is flat and articulates with the corresponding 

 facet on the trapezoid ; the other facet is antero-inferior, slightly con- 

 cave, ovate in shape and articulates with the adhering scale-like second 

 metacarpal. 



The Mdi^Ni/m. — The magnum (No. 918) is proportionally longer 

 antero-i)Osteriorly than in the llama and has a greater constriction in 

 front of the posterior hook and rather resembles that bone of the re- 



