FALCO HYPOLEUCUS, Gould.
G r e y F a l c o n .
Falco hypoleucus, Gould in Proc. of Zool. Soc., Part V III. p. 162.
Boorh-ga, Aborigines of Moore’s River in Western Australia.
Of this rare and beautiful Falcon I have seen only four examples, three o f which are in my own collection,
and the fourth in th at of the Earl of Derby. The specimen from which my description in the “ Proceedings
o f the Zoological Society ” was taken, was presented to Mr. Gilbert by Mr. L. Burgess, who stated that he
had killed it over the mountains, about sixty miles from Swan R iv er; subsequently it was obtained by
Mr. G ilbert himself in the vicinity of M oore’s River in W estern Australia; and my friend Captain S tu rt had
the good fortune to secure a male and a female during his late adventurous journey into the interior o f South
Australia. “ They were shot a t the Depot on a Sunday in May 1845, ju s t after service ; they had been
soaring very high, but a t length one descended to the trees on the creek, and coming within range was
s h o t; when the other proceeding to look after its companion was also killed. I t must be a scarce bird, for
no others were seen.”
The acquisition of the Falco hypoleucus is highly interesting, as adding another species to the true or
typical Falcons, and as affording another p roof of the beautiful analogies which exist between certain groups
o f the southern and northern hemispheres; this bird being as clearly a representative o f the Jerfalcon
o f Europe, as the Falco melanogenys is o f the Peregrine, and the Falco frontatus o f the Hobby; but as I
have more fully entered into this subject in my observations on the genus, it is unnecessary again to detail
them here.
The adult has the whole o f the upper and under surface and wings grey, with a narrow line o f black
down the centre of each feath er; a narrow ring o f black nearly surrounding the eyes; primaries brownish
black, which colour assumes a pectinated form on a mottled grey ground on the inner webs o f those
feathers ; tail-coverts grey, barred with brownish g r e y ; tail dark brownish, grey, crossed with bars o f dark
brown; irides dark brown ; cere, orbits, gape, base o f the bill, legs and feet brilliant orange-yellow; the
yellow becoming paler from the base o f the bill, until it meets the black tips o f both mandibles; claws black.
The young birds have the upper surface mottled brown and grey, and the under surface nearly white, and
more strongly marked with black than in the adult. A
The Plate represents the two sexes of the natural size.