BIRDS BUTEONINAE — BUTEO BAIRDII. 



21 



the descriptions given above, the principal difference between the specimens before us, and is 

 very probably dependent on age, and perhaps sex. 



This handsome and interesting species appears to be exclusively an inhabitant of western and 

 northern North America. 



The plates represent this bird in the first and third plumages described above. 



List of specimens. 



5154 

 5156 

 5155 

 5157 

 8540 

 8539 

 8541 

 4984 



Locality. 



Mouth of Yellow Stone river. 

 Mouth of White Eanh river . 



Knife river, Missouri 



Heart river, Nebraska 



Cochetope Pass 



do 



San Luis valley 



Pecos river, Texas 



When collected. 



Whence obtained. 



July 14, 1856 Lieut. Warren. . 



Sept. 6, 1856 do 



Sept. 10, 1836.... do 



Sept. 21, 1856....' do 



! Lieut. Beckwith. 



.do.. 



do 



. ' Captain Pope . 



Remarks. 



Collected by- 



Measurements. 



1 



Dr. Hayden . . . , 



do 



do 



Qums and feet 

 yellow 



20.63 



19.50 



I 21.95 



21.25 



Kreutzfeldt. 



do 



do 



22.50 



S H 

 h 5" 



48.5(1 

 46.5(1 

 50 00 

 51.25 



34.5(1 



15.50 

 15.50 

 16.00 

 13.50 



16.50 



BUTEO BAIKDII, Hoy. 



Baird'sBnzzard. 



Buteo Bairdii, Hoy, Proc. Acad. Philad. VI, 451, (1853.) 

 Cassin. B. of Cal. and Texas, pi. 41. 



Entire upper parts dark brown, with a purplish bronzed lustre, especially on the wings ; plumage of the head and neck behind 

 edged and lipped with yellowish white ; upper tail coverts yellowish wliite, with transverse bars of brown ; tail above brownisli 

 cinereous, with about ten narrow bands of brownish black, and tipped witli white ; under pans pale yellowish white, or fawn 

 color, with a few ovate and sagittate spots of dark brown ; a stripe of dark brown running downwards on each side from the 

 corners of the mouth ; cere, legs, and irides yellow. 



Older 9 — Upper parts very dark brown, or nearly black, with a purplish lustre ; under parts with almost every feather having 

 a large spot of brownish black, which color predominates on tlie breast, presenting a nearly uniforn color with the upper parts ; 

 throat with narrow stripes of the same color; flanks and inferior wing coverts with circular and oval spots of white ; tibice dark 

 brown , with transverse bars and circular and oval spots of reddish white; upper tail coverts reiidish white, with their outer 

 edges brown, and with transverse stripes of the same ; under tail coverts yellowish white, with transverse stripes of brown ; 

 forehead white ; cheeks yellowish white ; stripes from the corners of the mouth wide and conspicuous. 



Total length, 18 to 20 inches ; wing 15, tail 8 inches. 



Hab. — Northern and western North America. Spec, in Mus. Acad. Philadelphia and Nat. Mus. Washington. 



In the plumage, first described above, this bird bears some resemblance to the young of Buteo 

 lineatus, but has a much more mature appearance, and is easily distinguished by its smaller 

 size. It reserubles also in colors only the young of Buteo pennsylvcaiicus, but is much larger. 

 Though discovered in the State of Wisconsin, sjiecimens from various western localities are in 

 the collections of the expeditions. . 



Specimens recently collected by Lieutenant Warren show that the upper figure of our plate, 

 as cited above, really represents the young plumage. Lieutenant Warren's specimens are 

 scarcely fully fledged, and yet agree precisely with this figure. 



