BIRDS — BUTEONINAE — BUTEO MONTANUS. 



27 



Inthii plumage, which is evidently that of the yotinf; bird, the dark spots of the under parts are usually much larger and 

 mott) numoroua than in the young of BuCeo boreatit, in which wo have noror seen tho tiliiu3 and under tail coverts so strongly 

 barred as in tho present bird. 



Dimttuions. — Adult female, total length 23 to 35 inches, wing 16J to 17, tail 9 to 10 inches. Male, total length 19 to 22 

 inches, wing 15 to 16, tail S}., to 9 inches. 



This is a species much rosembling and nearly related to tho red-tailed buzzard (Buteo borealis) 

 of the States on the Atlantic, and in the examination of collections like the present made during 

 journeys across the continent, it is not without difficulty that a distinct range of locality can be 

 assigned to the two species. The most strongly characterized specimens of the bird now before 

 us are from tho countries west of the Rocky mountains, but it is evident from specimens in this 

 collection that this species is not restricted to those regions. It not only inhabits the moun- 

 tains, but extends into the countries at their eastern base. 



Of this rather difficult and obscure species, we have in the present collection no less than 

 thirty specimens, which, with several others from the collection of the Philadelphia Academy, 

 make a series probably representing all the stages of plumage dependent on age, sex, or season. 

 This series admits of division into the three stages above described. 



Our comparisons are made with a series of twenty-eight specimens of Buteo horecdis from 

 various parts of the United States east of the Rocky mountains ; generally, however, from the 

 vicinity of Philadelphia. The present species appears to be the larger, averaging in total length 

 about 24 inches in adult females, which, so far as can be determined from prepared specimens, 

 is nearly two inches greater than the average of the same sex of Buteo borealis. Tlie wing is 

 about 1^ inches longer. There are in the entire series of both species now before us not more 

 than three specimens that we have any difficulty in assigning to one species or the other, 

 though specimens of both constantly occur which cannot be recognized without difficulty, unless 

 series are at hand for comparison. 



List of specimens. 



3. 



O 



3 



S636 



sea* 



4S81 

 8U1 

 8»S 

 4372 

 8535 

 8534 

 4416 

 4631 

 4611 

 8536 

 8533 

 8549 

 £957 

 6956 

 4986 

 4985 

 8533 



Locality. 



Fort Steilacoom, W. T. 

 do 



.do., 

 .do., 

 .do., 



.do.. 



Shoalwater bay, W. T . 

 Takima river, W. T.... 



Fort Dalles, O. T 



Sanu Clara, Cal 



California 



Laguna 



Camp 149, N.M 



Camp 114, N.M 



Sorlli Plaue 



do 



Pecos river, Texas 



do 



Devil's river, Teias . . . 



Wben collected. 



Aug. 

 Sept. 



8, IMfi 

 — , 1856 



Ocl. — , 1854 

 March 21, 1854 

 Aug. 4, 1853 

 Dec. — , 1854 



Nov. 33,1854 

 March 16, 1854 

 Feb. 6, 1854 

 Aug. 1, 1857 

 do 



Whence and how ob- 

 tained. 



Dr. G. Suckley 



do 



Dr. Pott 



Gov. 1. 1. Stevens. 

 Dr. Suckley 



.do.. 



Gov. Stevens ..., 



do 



Dr. Suckley 



Dr. Cooper 



Major Emory... 



do 



Lieut. Whipple. 

 do 



-,1855 



Lieut. Dryan .. 



do , 



Capt. Pope 



do 



Major Emory. 



99 

 536 



14 

 185 



71 

 371 

 369 



Collected by — 



Dr. Suckley. 



Dr. Cooper . 

 do 



A. Schott 



do 



Dr. Kenncrly . 

 do 



W. S. Wood. 

 do 



1 Dr. Kennerly . 



Measurements. 



23.50 

 24.50 



23,00 

 24.00 

 !£2.00 



22.50 

 25.00 



53.00 

 51.00 



49.00 

 54.00 

 48.00 



54.50 

 53.00 



16.75 



18.00 

 17.50 



