116 MEMOIRS OF THE CARNEGIE MUSEUM 
relatively greater vertical diameter, the enlarged projection on the dorso-ulnar angle, 
which causes a slightly greater transverse diameter in this region, and also the 
absence of the third facet for the lunar on the ulnar face. The articular surface for 
the radius is divided into two parts, an antero-external and a postero-internal, as in 
Archxotherium. ‘The postero-internal facet is saddle-shaped, concave antero-posteri- 
orly, and constitutes the principal articulating surface of the proximal face. The 
antero-external facet is small, convex, continuous with the former facet, and descends 
steeply to conform with the anterior portion of the articular surface on the lunar 
On the ulnar face of the scaphoid there are two articulating facets for the lunar, 
one dorsal and one palmar, while in Archxotheriwm there are three. The dorsal 
facet is located on the prominent point which overhangs the ulnar surface of the 
radius and articulates posteriorly with the proximal radial face of the lunar by a 
broader surface than is the case in Archxotheriwm. The lunar facet, which is 
dorgal and distal in Archotheriwm, is, as stated above, absent in Dinohyus. This 
facet though small is quite distinct in the former genus, while in Dinohyus, the 
further development of the prominent ridge on the proximal face of the magnum 
has so effectually separated the scaphoid and lunar in this region that the two bones 
perhaps very rarely, if ever, came into actual contact. The palmar facet for the lunar 
is of large size and occupies the entire lunar face of the palmar process of the scaph- 
oid. Between the different facets the lunar face of the scaphoid is much excavated 
and extensively arched in the antero-posterior direction. ‘The latter character is 
chiefly due to the excessive outward turn of the large palmar process. Distally the 
scaphoid has three facets: one posterior for the trapezoid, one anterior for the 
magnum, while on the ulnar angle there is a long narrow facet which also articu- 
lates with the high and antero-posteriorly directed ridge on the proximal face of the 
magnum. ‘The articular surface for the trapezoid is concave antero-posteriorly and 
is continuous with the surfaces for the magnum. ‘The two latter surfaces are irreg- 
ularly convex and concave. Radially the bone is quite rugose and gently convex, 
while the anterior face is much more convex from side to side. 
From Kowalevsky’s illustration (88, Pl. X XVI, fig. 23) it would seem that the 
seaphoid of Entelodon has a smaller antero-posterior diameter, when compared with 
its vertical dimension, than is seen in the American forms. In Anthracotheriwm (see 
Kowalevsky, Paleontographica, Vol. XXII, p. 299; Pl. XI, fig. 38) the seaphoid has 
a remarkably close similarity to the scaphoid in the Hntelodontidx, as has been 
pointed out by Kowalevsky and Scott (87, p. 303). The scaphoid in Sus and Hip- 
popotamus on the other hand is more unlike that in the Hntelodontide, being broader, 
and of smaller antero-posterior diameter. 
