236 Mr. J. II. Gurncy's Nofeft on 



Witli reference to tliis question, it may he interesting to 

 quote the opinion of Dr. Elliott Coues, as expressed at p. 357 

 of his rceent work on the Birds of the North-west. Dr. 

 Cones there remarks : — " This dark plumage is an individual 

 peculiarity, not a normal stage of regular occurrence." 



The remaining American species of the genus Buteo may, 

 I think, be regarded as belonging to the central group of 

 that genus, of which B. vulgaris is the type; and in con- 

 sidering these, I propose first to refer to Buteo borealis and 

 its western repi'esentative, to which Mr. Sharpe assigns the 

 subspecific name of " montanus." With reference to this 

 appellation, Messrs. Baird, Brewer, and Ridgway write thus 

 in vol. iii. of the ' Land Birds of North America,' p. 288 : — 

 " It being certain that the Buteo montanus of Nuttall is 

 really the B. swainsoni, and not the variety of borealis so 

 called by Mr. Cassin, it becomes necessary to drop the name 

 in connexion with the present bird, and transfer it as a 

 synonym to swainsoni. In its place Mr. Cassin's name 

 calurus must be substituted, under which was described the 

 melanistic condition of the present variety of B. borealis.^' 



It would therefore appear that Buteo montanus of Mr. 

 Sharpe's work should rather bear the name of B. calurus. 



To define with precision the distinction between the true 

 B. borealis of North-eastern America and its darker and 

 more ferruginous western congener, B. calurus, is a difficult 

 and, I suspect, an impossible task ; for, great as is the diff'er- 

 ence in coloration between typical examples of the two races, 

 intermediate gradations occur which it is hardly possible to 

 divide by any satisfactory line of demarkation. 



Mr. Sharpe, in his article upon B. calurus, speaks of the 

 " western birds " as being '' much larger, more powerful, and 

 darker-plumaged than the eastern, or ordinary specimens of 

 B. borealis." 



This observation is undoubtedly correct as to the darker 

 plumage in the great majority of western specimens, but, 

 according to the measurements supplied by Messrs. Baird, 

 Brewer, and Ridgway, can hardly be said to hold good as 

 regards the alleged larger size of B. calurus. 



