208 
On some Species of Airthus and Budytes. 
be met by employing a fashionable theory which is baseless in 
face of existing facts, many of them only to be observed by 
the study of these birds in life. Now some forms of B. flavus 
are rather hard to separate (as skins only) from aberrant forms 
of B. viridis (cinereocapillus ); but there are mature females 
of the latter never to be matched by any mature female 
of B. flavus. This the confounders of the two species do 
not know, or they would never dream of identity. Each 
species is subject to considerable variation; and very large 
series of each, together with a knowledge of the birds in life, 
are indispensable to a correct comprehension of them. For 
instance, a mature female of B. melanocephalus may have either 
a brownish-grey head or a black one, nearly as black as that 
of the male; and the colour of the lower surface is similarly 
variable, from white tinged with yellow to a moderately pure 
yellow, save the throat and breast, which are always pale in 
the female. The female B. viridis will carry the rather strong 
yellow right to the base of the bill; and this female possesses 
a brilliancy of lower surface not possessed by any other female 
of the green-backed Budytce with which I am acquainted. 
The yellow abdomen of the female B. flavus changes to a sort of 
rufous tone on the breast; and this, with the broad brownish 
white supercilium, distinguish the species. Of the very dis¬ 
tinct female B. rayi I need not say a word; but I have said 
enough to show that the study of the mature females confirms 
the entire distinctness of the several species. 
The same great variation as regards the female is obser¬ 
vable in Budytes calcaratus, Hodgs.; and here let me ob¬ 
serve that B. citreoloides , Hodgs., is identical with B. citreolus, 
Pallas. 
It is a question whether the paler females are young birds 
or not. The difference may be one of mere complexion, as 
in the Peregrines ; but I have shot light-toned examples of B . 
calcaratus that would have laid their eggs certainly within 
the week. This was in Cashmere; and I searched long for 
the nests, but unsuccessfully. 
I spent much time in ascertaining the mature female plu¬ 
mages of the five species of Budytes of India; and the investiga- 
