44 



NEW YORK STATE MUSEUM 



views of the pelves of Cat h arte s a.septentrionalis 

 and Catharista, it will 'be observed that an entire vertebra 

 of the sacrum protrudes beyond the ilia anteriorly in the first named, 

 which is not the case in the Carrion crow. In fine, from what we 

 can see from the superior aspects of the pelves of the two vultures 

 we have been comparing, there are some very good differential 

 characters to be met with in this family. 



Interdiapophysial foramina constitute a marked feature of the 

 hinder part of the sacrum. There is a double middle row, always 

 very perfect, and a scattered outside row upon either side. They 

 are best marked in Cathartes ; next in Catharista ; less so in Gypar- 

 chus, and least of all in the condors, where they are confined to 

 the interspaces among the ultimate sacral vertebrae, and are com- 

 paratively of no very great size. 



The anterior margins of the ilia are finished off above by a 

 smooth and raised border, with jagged edges in front, which are 

 produced over the outer ends of the transverse processes of the 

 first sacral vertebrae in Cathartes and the condors. This border 

 is carried backward a certain distance, to be lost in the true gluteal 

 ridge, of which it is the anterior extension. It is less prominent in 

 Gyparchus, as seen in a good life-size figure of the pelvis of this 

 vulture given by Eyton in his Osteologia Avium. 



The last sacral vertebra, in all of the Cathartidae, although well 

 anchylosed with the one next beyond, is never completely grasped 

 by the ilia, its transverse processes always projecting a little behind 

 [see pi. 14, fig- 29]. 



The gluteal ridges meet then at a point, mesiad, in such of these 

 vultures as have the ilia in contact at a greater or less distance 

 beyond the antitrochanters ; from this point they diverge to form 

 bounding lines to the postacetabular region, being carried in their 

 course above the antitrochanters, in whose neighborhood they form 

 lateral angles, to be directed backward to terminate behind in the 

 produced iliac processes, one on either side. 



Generally speaking, the preacetabular region is concaved upon 

 either side, while the postacetabular is convexed, and, as in all 

 Accipitres, faces upward and backward [pi. 13, fig. 28]. the 

 hinder part of the pelvis, as it were, being deflected. 



■ The under side of the iliac surfaces anteriorly are roughly in the 

 horizontal plane, and the neural canal in the sacrum in this part 

 of the pelvis is subelliptical in form, with the major axis placed in 

 the vertical direction. In all of the Cathartidae the first sacral ver- 



