340 SCOTT. [Vol. XI. 



end is but little expanded and of nearly uniform width on its 

 dorsal face, though it is somewhat constricted in the middle of 

 the radial side. The radial facet is broader and convex in 

 front, narrower and concave behind. The distal end is de- 

 scribed and figured by Osborn and Wortman as having "its 

 articular surface divided almost equally between the unciform 

 and magnum." This description does not quite apply to the 

 adult female skeleton which is here described. While the two 

 facets are not far from being of equal width, a comparison with 

 DorcatJierium and Mosc/ms shows a tendency toward the tragu- 

 line method of displacement, in that the facet for the magnum 

 is more lateral and that for the unciform more distal. Conse- 

 quently, the salient beak formed by the meeting of the two 

 surfaces is not in the vertical median line, as it is in the 

 Pecora, but is shifted toward the radial side. The magnum 

 surface is the narrower of the two, but it extends farther to- 

 ward the palmar side ; it is slightly convex in front and con- 

 cave behind, while the unciform facet is concave throughout. 

 The scaphoid facets correspond to those already described on 

 that bone. On the palmar side the proximal end of the lunar 

 rises somewhat above the level of the scaphoid and has an 

 accessory lateral facet for the radius, though the contact is 

 less extensive than in recent Pecora. Another accessory 

 radial facet of the proximal end lies behind the principal one. 

 On the ulnar side of the bone are two facets for the cuneiform, 

 the proximal one of which is fiat and confined to the dorsal 

 half of the lunar, while the distal one is concave and extends 

 through nearly the entire depth. 



The cuneiform is relatively broad, but of proportionately 

 small dorso-palmar depth ; its principal difference from that of 

 existing tragulines and Pecora consists in the absence of any 

 facet for the radius. In these groups the displacement of the 

 ulna is to some extent compensated by an extension of the 

 ulnar facet posteriorly and down upon the outer side, but in 

 Protoceras the ulnar facet remains a narrow groove. As in 

 the Pecora, the infero-external angle of the bone is slightly 

 incurved to form a blunt hook. The pisiform facet is broad 

 and flat above, narrow and concave below, where it extends 



