86 On some European and Asiatic Eagles. 



and barred grey tail. From No. 1 it is easily separated by 

 its structural difference in form of nostril, and by its barred 

 tail ; and from No. 2 its rich colours and the strong tendency 

 to particoloured feathers sufficiently distinguish it. This 

 particoloured plumage partakes rather of the character of 

 the spotting upon the mantle of juvenile Aquila ncBvia in the 

 example sent me. The two-coloured feathers, however, are, I 

 understand, not constant. 



We have no record of the occurrence of the Indian A. fuU 

 vescens in Europe; nor have I ever seen an Indian-killed A. 

 ncevioides. I was much pleased to see the last species and 

 to observe its affinity to A. vindhiana; and yet its complete 

 distinctness is most striking. 



In our references to A. ncevioides, Mr. Gumey and I have 

 been playing at cross purposes, he having in view the true 

 A. ncevioides, while I was thinking of the Indian species so 

 misnamed. 



I recently identified A, orientalis. Cab. (misnamed A. clanga 

 by dealers) with A. bifasciata, Gray and Hardwick. To 

 this Mr. Gurney objects, on account of the former^s smaller 

 average size and darker colour. His series consisted of about 

 half a dozen of each. 1 have examined again my series of 

 each most carefully, and with the addition of the measure- 

 ments of two A. orientalis in the Norwich museum. I was 

 able to take three males and three females of each species ; 

 and I find the average of the wings to be — A. orientalis 

 21*5, and A. bifasciata 21*541, or practically no difference as 

 regards size ; and in respect to colour I find as dark a brown 

 in some of my mature A. bifasciata as in the very fine old 

 Bosphorus example of A. orientalis [vide Ibis, 1870, pp. 67, 

 68) . But neither size nor colour is a criterion when Eagles 

 are in question, but characteristics only. They vary exces- 

 sively in size ; and the Indian climate affects their colour to 

 such an extent that I have seen the same species, Aquila navia, 

 nearly black when newly moulted, and a pale sandy bird after 

 a few mouths^ exposiu'c. But it is not always time which 

 produces paleness : the colour of some examples is fast, 

 while that of others is the opposite. 



