flanks, and thighs ashy-brown; under tail-coverts brown, tinged with orange and broadly edged with
white, concealing the brown centres vto the feathers; under wing-coverts and axillaries orange, the
latter with ashy margins; quills dusky below, more ashy on the inner webs, which have a slight
tinge of orange: “ bill brown, lower mandible yellow almost to the tip ; feet greyish brown; iris
dark brown.” Total length 9*5 inches, culmen 0 9, wing 5*65, tail 3*65, tarsus 1*25.
Adult female. Not very different from the male, but hardly so black on the throat and
fore-neck, having a browner tinge on these parts. The wearing away of the edges to the under
tail-coverts leaves these feathers more distinctly orange-brown. The sides of the body are streaked
with dark brown. Total length 8*5 inches, culmen 0*9, wing 5*3, tail 3*5, tarsus 1*25.
Adult female in winter plumage. Lighter grey than in the breeding-pluraage, the ear-coverts,
cheeks, and sides of the neck like the back; throat and fore-neck black, but having all the
feathers edged with hoary white, producing a mottled appearance; remainder of under surface
pure white, the sides of the body more ashy, and streaked with dusky brown, these streaks being
very distinct on the upper part and sides of the breast.
Young female. Duller ashy-brown than the adults, with whitish marginal tips to the greater
Wing-coverts and upper tail-coverts; the rest of the wing-coverts with terminal triangular spots
of dull white; the back and scapulars with longitudinal whitish shaft-streaks; a distinct whitish
eyebrow; ear-coverts dark brown; cheeks, throat, and under surface of body white, the throat,
chest, and sides of the breast washed with orange-buff, and spotted with black; a distinct malar
line of dusky brown spots ; a few of the abdominal feathers with brown linear margins.
The extensive hybridization which apparently takes place between the present species and other
Thrushes is one of the most remarkable phenomena that I am acquainted with. The fact that the
Siberian Thrushes are mixed up together during the winter migration is doubtless the cause that
on their return to their breeding-quarters they pair with the allied forms. Of this there can be no
doubt in the case of M. atrigularis, for there are evident hybrids between it and M. rufieollis,
while there are some specimens with the flanks thickly spotted with black, which I believe to
be a cross with M. fuscata. A large proportion of the specimens obtained in the N.W. Himalayas
have some red in the tail, and the form called Turdus hyemalis by Dybowski occurs there. A
male from Gilgit in Colonel Biddulph’s collection appears at first sight to be a perfectly distinct
species from M. atrigularis. I t has an entirely red tail like M. rufieollis and has uniform greyish
sides and a pure white breast and abdomen. Evidently this form has more of the strain of
M. rufieollis in it than of M. atrigularis, but between this red-tailed bird and the typical darktailed
M. atrigularis there is every kind of intermediate plumage.
The adult male described and figured in the present work is in the Seebohm Collection : it was
obtained by Kibort at Krasnoyarsk on the 14th of April, 1878. The adult female described was
procured by Seebohm in the Yenesei Valley on the 8th of August, 1877. The young bird described
was sent by Kibort from Krasnoyarsk, and was shot on the 27th of July, 1878. [R. B. S.]