360 MEMOIRS OF THE CARNEGIE MUSEUM. 
The ungual phalanges of the third and fourth digits are similar to, though 
much smaller than, those on the second digit. They are sometimes quite asym- 
Fie.93. Proximal phalanx digit Fre. 94. Median phalanx Fie. 95. Ungual phalanx digit III 
III, left manus of M. elatus (No. digit III, left manus of M. of left manus of M. elatus (No. 1604). 
1604). X+#. 1, dorsal view; 2, elatus (No. 1604). x4. 1 
lateral view. dorsal view; 2, lateral view. 
Ai 
; <4. 1, lateral view; 2, proximal view. 
metrical, one prong of the bifurcated anterior terminations being much shorter 
than the other. The subungual process is generally less prominent than on the 
second digit. The phalanges of Macrotherium, as described and illustrated in 
various publications, and also as represented in the cast of the manus here used 
for comparison, are heavier on the external than internal digits. This is directly 
opposite to the conditions found in Moropus and it seems that the phalanges of the 
manus in the European genus have been misplaced and the position assigned to 
them should be regarded as erroneous. As already intimated it seems altogether 
natural to suppose that the second metacarpal having the proportions of that of 
ACS 
Fic. 96. Proximal phalanx digit IV, left ma- Fic. 97. Median phalanx digit IV, left manus 
nus of M. elatus (No. 1604). Xz. 1, lateral of M. elatus (No. 1604). X43. 1, superior view; 
view; 2, dorsal view. 2, lateral view. 
Macrotherium should have borne phalanges of larger size than those attributed to 
them by European authors. In Macrotherium the codssification between the 
first and second phalanges is not apparent, and the trochlea between the second 
and terminal phalanges is less obstructed than in Moropus. On the other hand in 
the large chalicotheroid from Pikermi the phalanges seem to be, as before stated, 
more nearly like those of Moropus elatus, with the first and second phalanges on 
the second digit codssified, and the duplex and terminal phalanges provided with a 
shoulder and buttress of nearly the same relative proportions as in Moropus. 
Nestorithertum is from a later horizon and is of even much larger size than the 
