PAL^EOSYOPS LEIDY, AND ITS ALLIES. 
285 
Tlie variety last described, No. 10,118, we may consider as an extreme form of 
this species, aiid we shall hereafter see when treating of P. vallidens, that in the 
latter species we have intermediate dental characters ])ointing to the species nnder 
consideration. 
The Skull. — (PI. 10, fig. l.)The skull figured is a composition of the two very 
fine specimens in the museum of the Academy of Natural Sciences of Phila- 
delphia, figured by Leidy in his work ; they are an occipital region and a facial por- 
tion of a skull from another individual. The restoration of the lower jaw is 
derived from the fine mandible in the Princeton collection No. 10,000. Leidy' 
has already given us a restoration of the skull of this s])ecies in his report, but in 
some respects it is rather exaggerated ; for example, the occipital region, in com- 
parison with the facial, is too high ; the anterior portion of the temporal fossa is 
too much excavated, and the curvature and form of the zygomatic arch is incor- 
rect. The general dimensions of the skull of this species as compared with that 
of the Tapir are very much broader and heavier, although their anterior and pos- 
terior dimensions are about equal. The facial axis of the skull was probably 
slightly bent upon the cranial. In the Tapir on the other hand, these axes are in 
the same straight line. The form of the facial region is very different from that of 
any living Perissodactyle, as on account of the long and overhanging nasals it gives 
this portion of the skull a different aspect from that of the Tapir, where the 
nasal bones are much abbreviated and reduced. 
The facial region of the skull is rather compressed, with a convex supe- 
rior surface Avhich gradually rises to the interorbital region. The latter 
portion is very much expanded and is depressed between the orbits, which 
form an abrupt concavity, from which posteriorly the froutals rise suddenly 
to form the much enlarged forehead so clniracteristic of this species. The gen- 
eral form of the cranium in P. paludosus in many respects resembles that of 
the Tapir ; that is to say, the frontal region is higher than the occipital, and 
forms a high and flat forehead traaisversely, being strongly convex from 
before backwards. The post orbital processes of the frontal are largely developed 
in this species, and the anterior temple ridges rising from them are very prominent. 
The surface of the skull between the temple ridges is very broad and slightly con- 
vex. From the interorbital region the tem])le ridges converge, but do not meet 
to form a sagittal crest until near the junction of the latter with the occipital 
border. The lambdoidal crest is well-developed in this species, and extends later- 
ally as far as the exoccipital region, but it is not nearly so much developed as in 
Limnohyops where it is very heavy. The occiput of P. paludosus is much 
broader than high, the portion above the foramen magnum being directed forwards. 
The superior portion of the occiput is concave and overhung by the lambdoidal 
crest. Viewed from the side, the skull shows nearly the same position of the 
’See Report U. S. Geol. Surv. of Terri, for ]873-Pl. xxxi. 
