304 SHUFELDT, Skcle^ou of Wedye-tailed Eai/le. [^^.'^^^i 



genus is Aqidla. Thus far the skeleton would appear to support 

 this arrangement. 



OvSTEOLOGY OF THE PECTORAL LIMB. 



As will be noted from an examination of Plate v., Fig. 8, there 

 are no especial characters to be found in the bones of the wing 

 of the Wedge-tailed Eagle, other than those occurring in the 

 corresponding bones in the wings of other Eagles. I'hese char- 

 acters have been quite fully described b}' me for several aquiline 

 species, in my various writings, and particularly does this apply 

 to the memoir on Pithecophaga, which appeared in the Fliilif- 

 pine Journal of Science in 1919. 



As compared with that of the Harpy Eagle, the Imnicrns of 

 the Wedge-tailed Eagle is a much more slender bone and a 

 shorter one. With respect to length, it differs in different indi- 

 viduals. For example, the humerus of the Wedge-tail received 

 from Captain White is but 17.9 cms. in length, while the corre- 

 sponding bone in the skeleton of the Wedge-tail from the Mel- 

 bourne Museum has a length of 18.5 cms. The humerus of 

 the Harpy Eagle at hand (No. 225806, Coll. U.S. Xat. Mus.) is 

 19.5 cms. long, and is a much stouter bone in all respects. Its 

 radial crest is shorter and higher at the apex of the triangle. 

 The sigmoidal curvature of the two bones is identical, and both 

 are thoroughly ])neumatic. 



With the usual Eagle character present, the humerus of the 

 Kamchatkan Eagle {T. pelagicus) indicates an aquiline species 

 of great size and i)ower. It has an extreme length of 22.7 cms., 

 with a corresponding bulk. Judging from the humerus alone, 

 I would say that the Kamchatkan Eagle was a bird fully one- 

 fourth larger in all respects than the Wedge-tail. 



Our Golden Eagle possesses a humerus very similar to 

 Uroaetus audax, while it averages a few millimetres longer. The 

 two bones possess almost identically the same characters, even 

 to the amount of curvature to the shaft. This curvature is more 

 marked in the humerus of FifJiccopho(ja — an Eagle in which 

 the bone ])rcsents an average length of 20 cms., and the species 

 as a whole is ]^robably a larger bird than the Wedge-tail. 



Even the American White-headed Eagle possesses a larger 

 and longer humerus than the W^edge-tailed species — that is 

 judging from the humerus belonging to the skeleton of an H. 

 leiicocephalus of ihe United States National Museum (No. 

 19,926), and it has an extreme length of 19.2 cms. 



Rones of the antihrachiiini and f^inioii are well .shown in Plate 

 v., Fig. 8, of the luesent paper. With resi)ect to the idna, that 

 bone in the arm of the White sj)ecimcn of ^^ audox has a length 

 of 22..^ cms.; that of the Alclbourne Museum si>ccimen a few 

 millimeters shorter, while the big Kamchatkan Eagle has an ulna 

 measuring no less than 25.0 cms. in length, and the Golden Eagle 

 from 22.3 to 22.4 cms. 



