xv, i Shufeldt: The Monkey -eating Eagle 41 



the hinder part of the pubic style was very different in the two 

 birds ; but this is by no means the case, for in the harpy those 

 elements are held in their normal position, as in life, by a lig- 

 ament stretching between their distal ends; while in Pithe- 

 cophaga, when this ligament has been cut, it allows the pubic 

 styles to spring away from each other and hang down as shown 

 on Plate IV. Moreover, the point of view from which I pho- 

 tographed those two trunk skeletons was not quite the same, 

 and this causes the reproduction of the rest of the bone to pre- 

 sent slight differences, which do not really exist. 



Viewed from above, it is to be noted that the ilia project 

 considerably beyond the sacral crest; and on the upper surface 

 of their anterior border there is a raised emargination which 

 is produced backward and finally runs out as a bounding line 

 to the postacetabular area of the superior surface of the sacrum 

 upon either side. As the ilia pass the "sacral crest," their 

 margins thoroughly coossify with it and in the same plane an- 

 teriorly — that is, up to the point where these bones begin to 

 diverge and are raised above the general surface on this dorsal 

 aspect of the bone. At the angle where this divergence com- 

 mences, the sacrum and the ilia are completely fused, and every 

 semblance of posterior openings of the "ilioneural canals" is 

 completely obliterated. So, too, with the rather abruptly down- 

 ward-sloping "postacetabular area;" here, likewise, every sem- 

 blance of sutural traces — the intersacroiliac ones — has been 

 absorbed; while the intervertebral foramina, so* conspicuous in 

 this area in the pelves of some birds, are reduced to mere little 

 pits in the general surface of the bone (Plate VI). 



Seen upon lateral aspect (Plate IV), the anterior two-thirds 

 of bone — or all that part anterior to and above the acetabulum 

 and antitrochanter — is supplied by the ilium of that side. Its 

 surface is generally concaved and faces upward and outward. 

 Anteriorly, its outer border is emarginated, and below this may 

 be seen the forepart of the pelvic sacrum, the continuation of 

 which, posteriorly, may also be observed through the large, cir- 

 cular acetabulum and immense ischiadic foramen; the former 

 is entirely lacking in any osseous base, while the latter occupies 

 fully one-half of the lateral area posterior to the rather large, 

 subtriangular antitrochanter and elliptical obturator foramen. 

 Posterior to this great ischiadic foramen, the lateral surface of 

 the ischium is triangular in outline, concave above, convex below, 

 and smooth throughout. The rounded posterior ischiac border 

 is nearly straight and presents no semblance of any indent that 

 might suggest the presence of an "ilioischiadic." 



