Osteology of Porzana Carolina. rH 
acetabulum, is long and narrow, being concave in the 
longitudinal direction and somewhat so in the vertical one. 
The sacrum in the postacetabular region and nearly 
opposite these rings shows usually three pairs of large in- 
terdiapophysial foramina, while the ilia further back pre- 
sent each a subquadrilateral convex surface, that lies 
nearly in the horizontal plane. These surfaces are pro- 
duced well behind the sacrum into rather triangular pro- 
jections, that turn slightly towards the median line, and 
each other (Fig. 4). 
A side view of the pelvis, (Fig. 5) shows that the neural 
spines of the leading sacral vertebrzee have thoroughly co- 
ossified to form a conspicuous crista, which is finished off 
along its superior margin by a thickened edge. Now, the 
antero-internal angles of the ilia nearly meet this latter rim, 
and from this point the iliac margin dips gracefully down- 
wards making rather a long concave curve, to rise again 
and arch over the cotyloid ring and ischiac foramen, to pass 
round behind, forming the boundary of the overhanging 
ledge that is seen to the rear of these apertures, and finally 
terminating at the sacrum after surrounding the posterior 
iliac projection. 
The external margin of this pre-acetabular portion of the 
ilium is much less curved, and it is in the horizontal 
and not the 
vertical plane, 
as is the curve 
alluded to 
above. The 
surface alluded 
oe to between 
Fig. 5. Right lateral aspect of pelvis Porzana carolina, these two lines 
x 2. Same specimen as shown in other figures. faces nearl y 
directly outwards, and only slightly upwards. Porzana 
carolina has quite a prominent propubis jutting out from 
iis usual site below, and in front of the acetabulum. This 
latter presents nothing worthy of particular note, while the 
ischiac vacuity behind it is more of asub-circular form than 
we find it in most birds. The ilioischiac area posterior to 
