HOLLAND AND PETERSON: OSTEOLOGY OF THE CHALICOTHEROIDEA. 341 
Moropus. The posterior portion of the facet for the magnum is also less deeply 
excavated in the former genus. 
The most noticeable difference in the lunar bone of Macrothervwm, when com- 
pared with the same bone in Moropus elatus or Nestoritherium, is detected in the 
almost total absence of the palmar hook in the former genus. This process, which 
is so prominently developed, especially in Moropus, is represented only by a minute 
eminence in Macrotherium. Other striking differences are manifested in the 
imperfect or absent proximal articular facet for the scaphoid, the ulnar position of 
the distal beak, and the rather small contact between the lunar and unciform in 
Macrotherium from Sansan. 
MEASUREMENTS OF LUNAR. 
No. 1604 No. 1700 
(M. elatus), (M. peterson), 
mm. mm. 
Greatest transverse diameter........ CURR HA ANU, Ste Rea 50 41 
Greatest antero-posterior diameter.....................---- 68 46 
Createstiverucalidiameters ase ane oe eee aioe 60 34 
Fie. 81. Cuneiform of M. elatus, (No. 1604). Fie. 82. Cuneiform of left manus of M. elatus (No. 
xz. 1, ulnar view; 2, radial view; 3, inferior 1800). Xz. 1, anterior, 2, ulnar, 3, radia}, 4, poste- 
view; 4, superior view. (Specimen some- rior 5, distal, 6, proximal, views. 
what defective.) 
The Cuneiform (Figs. 81-82).—In examining the illustrations, it may be 
noticed that the cuneiform of No. 1604 (see Fig. 81) is injured at its dorso-radial 
angle. By comparative measurements obtained from other individuals it is 
learned that the antero-posterior diameter of the cuneiform is greater than any of 
the carpals of the first row, while its transverse diameter is considerably less. 
This is ulustrated in Fig. 82, where we have given a drawing of a perfect specimen 
(No. 1800). A great portion of the ulnar face is occupied by a prominent eminence 
for muscular attachments. From the anterior part of this eminence the dorso- 
ulnar angle tapers rapidly, forming a sharp vertical ridge of the dorso-radial border 
of the bone. On the palmar face there is a large ascending tubercle, which plays 
a prominent part in the support of the articulation for the pisiform. The proximal 
