340 MEMOIRS OF THE CARNEGIE MUSEUM. 
ess being developed only inferiorly, while in Titanotheriwm the process is somewhat 
bifurcated, with a heavy inferior and a lighter superior portion. Aside from the 
elevated portion of the palmar process in T%tanothertum the general outline of the 
lunar in the two genera is not unlike. The articular facets for the scaphoid are 
located near the dorsal face; the upper one is on a prominent tubercle, as is well 
shown in Fig. 80, 3, while the one distally is sometimes divided into two portions, 
and fits neatly into the corresponding facet on the scaphoid described above. 
More distally the beak of the lunar has a large facet for the magnum, which is 
sub-triangular in outline. The posterior continuation of this facet for the magnum 
is basin-shaped and takes up the entire inferior face of the large palmar hook. 
This is not the case in Titanotherium, 
in which the inferior face of the palmar 
hook is more nearly equally divided 
for the magnum and unciform. On the 
ulnar side of the beak of the lunar in 
Moropus is an irregularly shaped facet for 
the unciform, which is divided into an an- 
terior and posterior portion, by an evenly 
rounded transverse ridge of considerable 
Fic. 80. Lunar of left manus of M. elatus (No. 
1604). 4. 1, dorsal, 2;~ulnar, 3, radial, 4 poste- : : 
rior, 5, inferior, 6, superior, views. smaller and is slightly concave trans- 
prominence. The anterior portion is the 
versely, convex antero-posteriorly, and 
subtriangular in outline, while the posterior portion is a shallow basin with more 
nearly triangular outlines. On the ulnar face there is one large plane facet for the 
cuneiform, which is D-shaped in its general outline in No. 1604. From Fig. 80, 2, 
it is seen that this facet is quite imperceptibly separated from the one for the 
unciform immediately below it. This slight separation is caused by a smooth 
rounded ridge, which extends antero-posteriorly and is plainly shown by the 
illustration. Above this facet the lunar is deeply excavated, forming a large sinus 
when the cuneiform is placed in contact with the lunar. In some individuals 
there is a minute facet for the cuneiform on the extreme upper margin, which 
indicates that the upper parts of the cuneiform and lunar sometimes actually came 
in contact with one another. 
The palmar process of the lunar in Nestoritherium is much shorter than in 
Moropus, but otherwise these bones in the two forms are very similar in general 
outline. The facets for the unciform and cuneiform respectively on the ulnar 
side of the distal beak are less distinctly separated in Nestoritheriwm than in 
