AXIAL SKELETON OF THE PELECANID#. 363 
Seen ventrally, the ilia extend out as in Phalacrocorax ; and there are three presacral 
foramina (s1, s*, s*) on each side. The lateral acetabular fossz (f') are notably different 
from those of Phalacrocoraz, owing to the encroachment inwards of the margins of 
the acetabula, which almost reduce the preaxial part of each fossa to a narrow chink 
(Plate LXI. fig. 8). 
The ridge running postaxiad inside the ischium is less marked; and there is no such 
expanse of ilio-ischial surface dorsad of the postaxial part of such ridge as there is in 
all the other three genera, above all in Pelecanus. On the other hand, the expanse of 
the ischial surface ventrad of the postaxial part of such ridge is greater relatively than 
even in Phalacrocoraz, and therefore very much greater than in Sula or Pelecanus. 
The pubes do not approximate ventrad as in Phalacrocorax or Sula. 
Tue Inivum. 
The process (st) described as existing in Phalacrocorax a little postaxial to the antitro- 
chanteric process also exists here, but is nearer to the last-mentioned process. This 
more postaxial process may be called the posttrochanteric process (Plate LXI. fig. 7). 
Besides the points above noted, a ridge runs mediad and preaxiad from this post- 
trochanteric process, and joins its fellow of the opposite side in the median antero- 
posterior iliac ridge. Another ridge (/r), very much stronger indeed, runs postaxiad from 
the same process, forming the very prominent ridge of the postacetabular part of the 
ilium, before noticed. This ridge causes each postacetabular ilium to present three 
surfaces, one externad, one dorso-mediad, and the other ventro-mediad; and the pro- 
minent ridge in question divides the externad from the dorso-mediad surface. 
The ilio-pectineal prominence (/p) is more sharp and prominent than in any other form 
of Pelecanidee. 
Tue Pusis. 
This is but a very feeble ossification, and unites with the ischium for a longer space 
than in the other Pelecanide. 
Tue Iscuium. 
This bone differs from that of the other Pelecanide by its greater postaxial expansion 
dorso-ventrally, presenting an extensive grooved surface (fig. 8, g) ventrally, as already 
noted in describing the ventral aspect of the pelvis. 
Tue Ries. 
There are seven or eight vertebral and six sternal ribs. 
‘Tue VERTEBRAL Riss. 
The first two belong to the cervico-dorsal vertebre, and haveno corresponding sternal ribs. 
The second may or may not have an unciform process; and the same is the case with 
the seventh rib. The eighth, when present, has no such process, 
The last rib has no tubercular process. 
VOL. X.—ParT vil, No. 7.—August Ist, 1878. 3D 
