HOLLAND AND PETERSON: OSTEOLOGY OF THE CHALICOTHEROIDEA. 351 
and Nestoritherium is quite striking. It is, however, seen that the heavy tuberosity 
on the radial angle, near the proximal end, is relatively more prominent and extends 
across the entire palmar face in Macrotherium, while in Moropus and also in Nestori- 
thertum it is of lighter development and ends abruptly on the radial angle, being 
then succeeded on the palmar face by a rough area more or less excavated. The 
tuberosity near the proximal end which points in the ulnar direction in Moropus 
elatus is as stated a broad flange which overlaps and articulates with the dorsal 
face of Me. III, and also carries a facet for the magnum on the extreme proximo- 
dorsal angle. In Nestoritherium this flange is entirely lacking while in Macro- 
therium the tuberosity has no separate facet for the magnum; it is more cube-like, 
does not overlap the dorsal face of Me. III, but articulates with that bone by 
lateral contacts. The shaft and distal end are still more similar to the characters 
met with in Moropus, and, as already pointed out by Professor Osborn,** there is 
no question that the animal had a sub-digitigrade foot. In fact the manus when 
properly articulated indicates a more digitigrade position than was given to it in 
Osborn’s modified restoration of Macrotherium (l. c., p. 120). In addition it may 
also be said that Macrotheriwm in all probability has the larger terminal phalanx 
on the second digit. The short and heavy metacarpal II of Macrotherium points, 
as does the same bone in Moropus, to the fact that it carried the heaviest terminal 
phalanx. In Moropus it has been shown that Me. II carries the heaviest phalanges 
in the manus,” and an illustration of the manus of Macrotherium is given under 
that species (see Fig. 4) in order to show the modified position, which we believe 
to be correct, when compared with the manus of Moropus. The manus has the 
characteristic ungulate displacement of the carpalia in both the European and 
the American forms. 
In comparing Me. II of Moropus elatus with the cast of the corresponding 
bone of Schizothertum priscum from the Phosphorites of Quercy it is extremely 
interesting to note the close similarity in the two. There is practically no difference 
in the distal trochlea and the shaft between the European and American genera, 
while the facet for the trapezoid is proportionately larger and that for the magnum 
smaller and probably placed more laterally in Schizotherium than in Moropus.** 
In Schizotherium the facet for the trapezium or possibly a remnant of Mc. I* is 
86 American Naturalist, Vol. XX VI, 1893, pp. 118-119. 
7 Peterson, O. A., American Naturalist, Vol. XLI, 1907, pp. 746-748. 
88 From the cast it appears as though the facet for the magnum in the original bone might be broken 
off, in which case the facet would be larger and also occupy a similar overhanging ridge seen in the corresponding 
region of Me. II in Moropus elatus. 
59 Filhol (Ann. des Sciences Naturelles, Tome XVI, 1894, pp. 141-144) has demonstrated that there was 
a Me. I present in Schizotherium. 
