POMATORHINE SKUA. 
95 
white • the central tail feathers rarely project for more than two 
inches. Like other members of the genus Stercorarms, the 
Pomatorhine Skua has a melanistic phase, which is generally 
considered to occur in old birds only, because of the yellow 
which is seen on the neck. Mr. Saunders, however, doubts 
whether any of these dark specimens are really old birds, and 
he quotes an instance of a specimen kept alive for some years 
by the late Mr. Booth, which gradually became whiter and 
whiter on the lower parts of the body. 
Young. — Sooty-brown above, the head and neck unifoim, 
but the mantle and hack mottled with rufous edgings to the 
feathers ; wing-coverts obscurely edged with rufous, the greater 
coverts and scapulars somewhat more plainly margined ; 
upper tail-coverts banded with sooty-brown and white or sandy- 
buff- tail-feathers sooty-brown, slightly edged with rufous at 
the tips ; sides of face and throat uniform sooty-brown ; under 
surface k body dull ashy-brown, with concealed whitish bars ; 
the abdomen paler and crossed with dusky bars ; the under tail- 
coverts banded with dusky-brown and huffy-white; sides of 
body darker than the breast ; under wing-coverts and axillaries 
banded with blackish-brown and white ; lower primary-coverts 
white, with dusky bands at the ends ; quills blackish below, 
with a great deal of white towards the base of the inner web ; 
“bill brown, with a greenish tinge ; tarsus often blue or grey 
in patches; bases of the toes yellowish ” {H. Saunders^ 
Characters.— The larger size and darker feet, with the brown 
hind-toe distinguish young birds of the Pomatorhine Skua from 
the young of the other two species of Stercorarius. The adult 
bird is known by its greater dimensions, the wing being over 
fourteen inches, and by the greater bre.idth of the central tail- 
feathers, which are rounded at the ends, and project four 
inches beyond the others, being twisted vertically. (Cf. 
Saunders, Cat. B. Brit. Mus. xxv. p. 322). 
Range in Great Britain. — A migrant to the seas of the British 
Islands, sometimes occurring in large numbers, as in 1879 
1880. Many individuals remain on our southern coasts during 
some winters, and specimens have been obtained inland after 
severe gales. On the northward migration in spring, t e 
species is seldom observed. 
