478 Mr. J. H. Gurney's Notes on 



wing-covertSj the peculiar dark brown tint which is also cha- 

 racteristic of the adult B. fuUginosus . 



Messrs. Salvin and Godraan have kindly lent me a melan- 

 istic specimen of Bideola brachyura from Veragua, killed 

 whilst moulting, and retaining a sufficient portion of the old 

 plumage in great measure to verify this remark, which is 

 further borne out by another melanistic specimen belonging 

 to the same gentlemen, and also obtained in Veragua, in which 

 the moult appears, from the character of the plumage, to have 

 taken place some months before the bird was killed. The first 

 of these specimens has the interspaces on the upper part of 

 the outer rectrices white on both webs; but this is not a con- 

 stant character, and is therefore not to be relied on. Both the 

 above-mentioned specimens retain the white forehead, which 

 is conspicuous in normal examples, and which is probably 

 constantly characteristic of the adults of this species, though 

 not of immature specimens. Another and, I believe, a con- 

 stant distinction is, that in Buteola brachyura the dark trans- 

 verse bars on the tail are more strictly horizontal than in the 

 adult birds of Buteo fuUginosus, in which the central portion 

 of these bars is lower than the extremities, as shown in the 

 figure of this species in the ' Transactions of the Zoological 

 Society,^ vol. iv. pi. 62, and in the ' Birds of North America,' 

 by Baird, Cassin, and Lawrence, pi. 15. fig. 1. I will add 

 one other element of diagnosis between these two Buzzards : 

 the space between the tip of the longest tertial and of the 

 longest primary, though somewhat variable, is, on the average, 

 decidedly less in Buteola brachyura than in Buteo fuUginosus . 

 The following tables will serve to illustrate this peculiarity, 

 and also to show how closely the two species approach each 

 other in their general dimensions : — 



