18 MR. A. ANDERSON ON THE (Jan. 5, 
than in any Indian-killed examples having the same peculiarity; and 
in India, according to my experience, the opposite variety, viz. the 
white-billed ones, predominate. There is no reason why both forms 
should not intermingle at Aden. The specimens I allude to have 
their claws quite worn away, caused, no doubt, by the rocky nature of 
the ground. 
8. FaLco PEREGRINUS, Gmel. 
On the 11th of February last I saw a Peregrine actually hunting 
by moonlight: the full moon was high up in the sky; and several 
stars had been visible for fully half an hour. Returning homewards to 
my camp through a marsh, I was startled by the sudden appearance 
of some ducks “(Anas pecilorhyneha), which dived simultaneously 
with their splash into the water. The Falcon towered overhead and 
then flew backwards and forwards several times over the same ground, 
almost skimming the surface of the water. 
The following morning I had several shots at this bird, but without 
success ; the native fowlers who were engaged in netting wild fowl 
assured me that they had seen her at that one place for a long time, 
and that she invariably roosted on a large bough of a mango tree, 
close to the edge of the jheel. 
Thecrepuscular habits of this Falcon have not been recorded before, 
so far as I am aware of. 
9. FALCO PEREGRINATOR, Sund. 
On the 19th of November last I procured another specimen of 
this beautiful Falcon, making in all three females. This appears to 
be a fully adult bird: the head, nape, and cheek-stripe are almost 
black, and only one or two feathers are wanting to make it into 
“‘atriceps”’ of Hume; upper plumage generally slaty blue, getting 
lighter towards the tail-coverts, the whole of the feathers being more 
or less barred with blue of a darker shade; tail unicolorous with 
the back, and barred with dark slaty blue; chin, throat, and upper 
breast unspotted white, tinged with buff; from sternum downwards 
bright ferruginous rufous, barred on the flanks, and spotted on the 
abdomen with slaty blue; tibial plumes greyish, tinged with laven- 
der, and minutely barred with blue of a light shade. 
The Shaheen alluded to in a former paper (P. Z.S. 1871, p. 678) 
is an immature bird: the whole of the upper plumage generally, 
including the tail, is dark cinereous or dusky black, the feathers of 
the back being edged with rufous, and the tail barred with the same 
colour ; the upper tail-coverts are blue, thus indicating a transitional 
stage; chin, throat, and upper breast as in the mature bird, but the 
feathers are dark-shafted ; lower breast, flanks, sternum, and tibials 
bright ferruginous rufous, the breast and flanks having longitudinal 
ne stripes, the sternum and tibials slightly barred with light 
blue. 
Of the varied country of the Doab the enormous jheels, woods, 
and plains have each its representative Faleon: the Bhyree affects 
swamps, the Shaheen wooded regions, especially in the vicinity of 
