310 THE OSTEOLOGY OF ELOTHERIUM. 
VIII. THe Hinp Line. 
The pelvis is remarkable in many ways. As a whole, it is curiously long and 
narrow, except anteriorly, where the sudden and strong eversion of both ilia gives it con- 
siderable breadth. The ilium is elongate, and has a long, heavy, trihedral peduncle, 
which expands quite abruptly into the broad anterior plate. This plate is very strongly 
eyerted in its antero-inferior portion, and in shape is not at all like that of Sus, or of most 
existing artiodactyls, but rather resembles that of such ancient perissodactyls as 
Paleosyops. The plate rises high above the sacrum and conceals much of that bone from 
view, when the pelvis is seen from the side; the gluteal surface is concave and the sacral 
surface strongly convex; the suprailiac border is quite thin for most of its course, but 
becomes very thick and rugose at its inferior angle. The ihac surface is relatively wide 
and may be traced through the whole length of the bone, the pubic border being very 
distinctly marked throughout. The ischial border is, for the most part, thick and 
rounded, but becomes sharp and compressed above the acetabulum. The pectineal process 
is a very prominent and rough tuberosity, and a second rugosity lies above and behind 
it. The acetabulum is rather small, but deep, and is of almost circular form; its 
articular surface is but little reduced by the deep and narrow sulcus for the round 
ligament. 
The ischium is likewise elongate, though much shorter than the ilium; above the 
acetabulum its dorsal border arches upward into a high, thin and roughened crest, the 
ischial spine, very much like that seen in Sus, behind which is a distinct ischiadic noteh | 
a difference from the true pigs, which have no such notch. For most of its length, the 
ischium is laterally compressed, but expands posteriorly into a large, thick plate, with 
eyerted hinder border and yery massive tuberosity. The pubis is short, heavy and 
depressed. The symphysis, in which both the pubes and the ischia take part, is very 
long, the posterior notch between the two ischia being shallow. Consequently, the 
obturator foramen is much elongated antero-posteriorly, and of oyal shape. This region 
of the pelvis is entirely different from that of Sus, in which the ischia are widely 
separated behind, the symphysis is short, and the obturator foramen is nearly circular in 
outline. In Hippopotamus the pelvis is more like that of Hlotherium, but is much larger 
and more massive in every way; the peduncle of the ilium is not so elongate or so 
slender, the spine of the ischium is very much less prominent, and the posterior expansion 
of the ischium is yery much larger and heayier. Unfortunately, the pelvis is not 
sufficiently well known in Ancodus or Anthracotherium for comparison with that of 
Hlothervum. 
The femur is a long and proportionately rather slender bone, The proximal end is 
