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PAL.EOSYOrS LEIDY, AND ITS ALLIES. 
PaUeosyops shows its closer affinity to Tapirus than to Rhinoceros in the fora- 
mina ol its atlas. 1 he large size of the vertebral centra is observed as a striking 
characteristic in the axial skeleton, and one which is carried still farther 
in Diplacodon. The long and narrow form of the sacrum departs widely from 
the characters of this bone in recent forms ; and lastly, the very short caudal 
region is different from that of Rhinoceros. The characters of the appendicular 
skeleton are interesting, and differ considerably from those of recent I’erissodactyles. 
The shortness and breadth of the scapula, the large size of the ccjracoid process, the 
presence of the scapular tuberosity and the want of any coraco-scapular notch 
are of interest as characters of this bone. The difference in shape and 
subdivisions ol the trochleae of the humerus in this species is very striking when 
compared with those of the Tapir or Rhinoceros. The form of the bones 
of the lower arm is found to be closely similar to those of the Tapir, although 
the ulna, in its relation to the carpus, is somewhat different. In the carpus is 
found many striking characters very different from those of the Tapir. The follow- 
ing are some of the most important : the mesaxial line of the manus passes 
nearer through the ectal side of the metacarpal III than it does in the Tapir, and 
there is not the same disparity in the size of the metapodials in Palceosyops as com- 
pared with those of the Tapir; in other words the metacarpal III approaches nearer 
the size of metacarpal IV than in Tapirus. It was also found that metacarpal V 
was not as much reduced as in the latter form. The penetration of the distal face 
of the lunar betAveen the magnum and unciform, is a character not found in the 
Tapir. The more vertical lunar-magnum articulation is also a peculiarity of this 
carpus, this character being greatly augmented in the allied genus Limnohyops. The 
form of the unciform is very different from that of the Tapir and its large contact 
with the lunar is striking. 
The square form of the cuneiform and the shutting out of the pisiform from 
the anterior aspect of the carpus distinguishes this species from Tapirus. In its 
short and Avide-spreading metapodials P. paludosus differs Avidely from recent forms. 
In its rather short and broad pelvis it approaches the Rhinoceros, but differs very 
much from the Tapir in the Avant of a triradiate ilium, this bone in P. paludosus 
being undiAuded. Most of the characters of the femur are found to be closely 
related to those of the Tapir, but in the flatness of the lower portion of the shaft 
and especially of its 23osterior face it differs from the latter. The fact that the 
femur of P. paludosus lacks a fossa for the flexor perforatus distinguishes it also 
from that of the Tapir. The form of the great trochanter of the femur is 
found to be intennediate betAveen that of Tapirtis and Eqtms. The large size of 
the lesser trochanter is also a conspicuous feature of the femur of P. paludosus. In 
the shape of its tibial tuberosity and the want of an incision for the extensor muscle 
of the tibia it differs from the femur of Tapirus. The Avide separation of the facets 
of the calcaneum and astragalus and the large contact betAveen the latter and the 
cuboid are found to be different from the condition of the parts in the Tapir. In 
