Falco babylouiciis atid Falco barbarus. 159 



than the males, and some adult females are more rufous on 

 the under surface than any of the males that I have examined. 

 Such a female is well represented in the plate of this Falcon 

 given in Gould's ' Birds of Asia.' The adult females of this 

 species are also more cross-barred with dark lines on the 

 under tail-coverts than is the case with the adult males. 



The less rufous adult females of F. babyloniciis greatly 

 resemble in colouring the most rufous adult females of 

 F. purlieus, but the males of these two species resemble each 

 other much less closely than do the females^. 



I may here remark that when F. babylonicus first assumes 

 the adult plumage, the interscapular feathers, especially in 

 the males, are edged with a rather dull rufous brown, which 

 disappears as the bird advances in age ; also that the trans- 

 verse bars on the basal portion of the tail, which are usually 

 somewhat strongly marked when the bird first attains the 

 adult dress, gradually become obsolete and disappear more 

 or less completely in the course of subsequent years. 



In the P. Z. S. for 1876, pi. xxiii., a figure is given of a male 

 Falcon which was shot in the Etawah district of Northern 

 India by the late Mr. Andrew Anderson, who referred it to 

 F. babylonicus, with which identification I concurred ; but 

 Mr. Hume, in ' Stray Feathers ' for 1877, p. 140, expressed 

 his opinion that the bird was too small for F. babylonicus, 

 and that it should have been referred to F. barbarus. In 

 deference to this opinion, and considering that Mr. Hume 

 had enjoyed superior opportunities to either of ourselves for 

 examining specimens of F. babylo?iicus, we acceded to his 

 view, and expressed our concurrence with it in the P. Z. S. 

 1878, p. 2 ; but after examining with some care the series 

 of these Falcons now preserved in the British Museum, I 

 have reverted to my original opinion, and believe that Mr. 

 Anderson's Falcon, now in the Norwich Museum, and several 

 other Indian Falcons which Mr. Hume referred to F. barbarus 

 (in which I followed him in 'The Ibis,' 1882, pp. 311, 312) 

 are, in fact, males of F. babylonicus, my present impression 



* For a detailed description of several adult males and females of Falco 

 pu)iivus, see ' The Ibis ' for 1882, pp. 313 to 321. 



