38 BULLETIN OF THE NUTTALL 



This plumage is so well represented in the upper figure of Plate 

 XXXIII of Naumann's Vogel Deutschlands, that the illustration 

 must have been taken from an exceedingly similar specimen ; the 

 figure, however, represents a slightly darker bird, with a few spots 

 on the breast and lesser wing-coverts. It is also very much like the 

 young of Buteo borealis krideri, as represented in Plate V, Pr. Ac. 

 Nat. Sci. Philad., 1873, so far as regards the relative amount of 

 brown and white ; but the markings are quite different, especially on 

 the remiges and rectrices. 



Females. 

 Light Phase, Adult (No. 56,107, Germany). Above grayish-brown, 

 quite light on the tertials, some of the wing-coverts, and scapulars, which 

 have still lighter (nearly white) borders ; all the feathers bordered with a 

 paler, grayer shade, and showing distinct black shafts ; upper tail-coverts 

 brown, narrowly tipped with soiled pale huff, the outer webs with a 

 slight mottling of ochraceous. Tail grayish-brown narrowly tipped with 

 dull buffy white, and crossed with nine or ten narrow bands of dusky, 

 these mostly indistinct, but well defined on the inner webs of the interme- 

 dke where the ground color is lighter and mixed with ochraceous. Head, 

 neck, and breast light brown, the feathers edged with whitish, causing a 

 slight streaked appearance ; flanks uniform brown, the feathers with nar- 

 row whitish tips ; abdomen white, heavily spotted with dark brown ; this 

 abdominal belt separated from the lighter and more uniform brown jugular 

 patch by a somewhat crescentic pectoral belt of white nearly free from mark- 

 ings ; tibiae nearly uniform brown, lighter in front and on the inside, the 

 longer plumes tipped with light fulvous ; crissum immaculate white. 

 Lining of the wing mixed rusty-rufous, buff and brown. Wing, 16.00 ; 

 tail, 9.30. 



This specimen presents a curious and very strong resemblance 

 to the adult Archibuteo lag opus in the coloration of the lower parts, 

 not only in the colors and markings but in the peculiar pattern. 



Dark Phase, Adult ? (No. 56,109, Germany). — General color sooty-brown, 

 this darkest on the head, neck, back, and breast (which have a decided 

 purple reflection in certain lights), the general duskiness relieved only 

 by rusty edges to the feathers ; scapulars " spattered " or blotched with 

 pale cinnamon-rufous ; rump and upper tail-coverts uniform sooty-brown, 

 the latter with very narrow and indistinct rusty tips. Tail grayish-brown, 

 with narrow bands, of which about eight or nine are distinct, the inner 

 webs of the middle pair much tinged with rufous. Abdomen marked 

 with broad bars, or bands of dark brown and buffy-white, of about equal 

 width ; the white bars most distinct and regular anteriorly, thereby throw- 

 ing into greater relief the dusky pectoral patch, which has a convex poste- 



