^1-9^'l SHUFELDT, Skeleton of Wechje-iaUed Ecujle. 303 



the widths are equal, it is relatively somewhat longer than the 

 sternum in the Golden Eagle. I have already pointed out, in 

 my paper on Pithecophaga, some of the osteological characters 

 of the sternum of Eagles, and devoted Plate v. to the trunk 

 skeleton of the Hari)y Eagle. 



Now while these latter birds agree pretty well in this part of 

 their osteology — more particularly in their pelves — not sufficient 

 attention was paid to the sternum of Thrasaetos liarpyia. In 

 some respects this bone differs from that of any other Eagle at 

 hand at this writing. Some disease or other in the specimen 

 before me (Xo. 225806, Coll. U.S. Nat. Mus.), had attacked the 

 coracoidal grooves and sternal extremities of the coracoids, 

 causing considerable exostosis ; and it is a little difficult to say, 

 from this specimen, whether the grooves in question decussate 

 or not. I am, however, strongly inclined to believe that they 

 do. thus agreeing in this particular with most existing Eagles. 

 This Harpy's sternum is very deep and capacious ventrally, and 

 its posterior moiety differs in one respect from the sternum of 

 any other species of Eagle before me at this waiting. Its entire 

 xiphoidal part is broad and handsomely rounded. There is a 

 large elliptical fenestra on either side, while the most striking 

 feature consists in the fact that the outer angles of this part of 

 the bone are considerably produced lateralwise beyond the costal 

 border of the bone, and curve forwards, each as a broad, 

 rounded, triangular hook, with its apex pointing to the front. 

 The transverse line between the apices of these processes meas- 

 ures 8.3 cms., while the transverse line measured directly anterior 

 to them, from one edge of the sternal margin to the other, is 

 but 6.5 cms. Taken as a whole, the hinder margin of this bone 

 is rounded, the concavity being to the front. On either side of 

 its central part there is a shallow notch. The fenestrse are well 

 within this border. 



The anterior pair of costal ribs in the skeleton of this Harpy 

 are short and small, and their sternal ends articulate with a 

 minute facet on the anterior margin of the costal process of the 

 same side. This is unusual, and different from any Eagle ex- 

 amined by me. 



The pelvis of the Harpy Eagle is considerably compressed 

 from side to side as in Pithecophaga, even to a slightly greater 

 extent. To a slight degree the Wedge-tail also exhibits this 

 character, while the sternum is most spreading in the Kamchat- 

 kan bird. 



In a survey of all the general osteological characters presented 

 on the part of the trunk skeletons of these Eagles, I would say 

 that, in this part of their osteolog>^, the Wed.ge-tailed Eagle and 

 the Golden Eagle (Aquila chrysaetos) were in the closer agree- 

 ment, the latter being somewhat the larger species. Sharpe, in 

 his "Hand-List" (vol. i., p. 260), places t^roaeius as the leading 

 genus in the sub- family .Iquilincr, and, in the same group, the next 



