xv, i Shufeldt : The Monkey-eating Eagle 33 



Passing again to the dorsal aspect of the cranium, it will be 

 observed, in the craniofacial region, that a considerable depres- 

 sion or concavity is present in the median area ; posterior to this 

 the frontal region is broad and iiat, with the superior orbital 

 margin cultrate. As in most eagles, the broad cranial vault is 

 rounded and smoeth, being marked only by the wonderfully fine, 

 rambling, anastomosing lines that in life harbor the vessels of 

 that region. I find these very well marked in the cranium of a 

 white-headed eagle (Haliseetus leucocephalus) (Plate II, fig. 1) 

 where, likewise, the depression in the craniofiontal region is 

 pronounced. Throughout the diurnal Raptores, this character 

 varies to some degree for the species. It is fairly well marked 

 in the cranium of Morphnus guiane?tsis; and several of the cra- 

 nial characters thus far described in the cranium in Pitheco- 

 phaga are more or less in agreement with the corresponding 

 ones in this bird (Plate II, fig. 3). This in no way takes size 

 into consideration, for Morphnus is not more than half the size 

 of the monkey-eating eagle while, in a way, it does refer to the 

 marked craniofacial depression, the lacrymals, and the general 

 form of the osseous superior mandible. No other parts whatever 

 have been seen or examined by me, and even the remainder of 

 this cranium is very imperfect. When the material was selected 

 for me at the United States National Museum, in addition to 

 those designated by myself, this imperfect cranium of Morphnus 

 was included. 



In Gypaetus barbatus a lacrymal does not support a free distal 

 piece as in some eagles, while the superior outstanding portion 

 is to a degree elongate and to some extent twisted upon itself. 

 This bird has considerably more eagle in its skull, and in the 

 rest of its skeleton for that matter, than it has vulture. How- 

 ever this may be, it has no special affinity with Pithecophaga, in 

 so far as its skeleton would seem to indicate; and it is very 

 much to be doubted that any of the rest of its morphology would 

 point to any such relationship. Nothing would be gained, there- 

 fore, by a comparison of the skeletal characters of these two 

 birds, beyond a demonstration of the fact that they possess no 

 near relationship ; and this much is evident to any expert avian 

 osteologist at a glance. This in no way applies, however, to such 

 a form as the big eagle of Korea, Thallasoaetus pelagicus, a 

 complete disarticulated skeleton of which (No. 18222, United 

 States National Museum) I have before me. Paul L. Jouy col- 

 lected it in that country many years ago. In its cranium it 

 exhibits all the aquiline characters of an average eagle, including 



lfi63ie 3 



