44 MR. ST. GEORGE MIVART ON THE 
THE PELVIS. 
When viewed preavially, the pelvis differs from that of Apteryx, and agrees with the 
same part in the other genera, in that the ilia form a less obtuse angle. It, however, 
agrees with that of Apteryx in the great extent to which the ischia and pubes come into 
view. 
Viewed laterally, the close resemblance of this bone in the position and proportions 
of the ischium and pubis is striking, as also is the relation of the acetabula to the spinal 
column ; for, as in Apteryx, a great part of the aperture of the opposite acetabulum can 
be seen through the nearer one. The ilia are much flattened behind the acetabula; so 
that what in the other Struthionide (except Apteryx) is the supratrochanteric process, 
is here but the external angle of this dorsally flattened expanse of bone. The ilium does 
not extend back either so far as the ischium or pubis; and the two latter bones slightly 
unite distad. The interobturator processes (tending to separate off the most preaxial 
part of the obturator foramen) are faint, and thus resemble those of Apteryx, though 
they are rather more marked than in that genus. 
Viewed ventrally the pelvis is remarkable for its extreme breadth, exceeding in this 
respect all the other Struthionide, and this not only absolutely, but relatively also. 
Between the acetabula are the two large fosse (fig. 42, f/f) already spoken of as 
conditioned by the non-development of the transverse processes of the more postaxial 
lumbo-sacral vertebrae. These fossee are subcrescentic, with the convexity of each cres- 
cent mediad. In the Apterya they are more elongated; in Dromeus and Casuarius 
they are very small indeed. In the specimens examined the ilio-pectineal processes 
are very little developed, thus differing greatly from Apteryz. 
Viewed dorsally the most noticeable distinctive feature is the excessive breadth of the 
more postaxial part of the pelvis. 
The tlium has had its main characters already noticed. 
The pubis is more slender relatively than in any genus except Apteryx, in which the 
slenderness is considerably more remarkable still. 
The tschium in its dorso-ventral breadth, and in its great divergence ventrad from 
the ilium, closely resembles the ischium of Apterya, and differs from that of every other 
genus of Struthionide. 
THE RIBS. 
There appear to be eight vertebral ribs on each side; and of these the fourth, fifth, 
and sixth (or at least the fourth and fifth) join the sternum by the intervention of 
sternal ribs. In their curvature the vertebral ribs resemble those of Casuarius, but 
they are more slender and more equal in length. The third, fourth, fifth, sixth, and 
seventh are the longest, and are of very similar length and slenderness. There are no 
indications of uncinate processes. The sternal ribs seem also to be slender. They 
