POMATORHINE SKUA. 95 



white ; the central tail feathers rarely project for more than two 

 inches. Like other members of the genus Stercorarius^ 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 uniform, 

 but the mantle and back 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 of 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 buffy-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 wung being over 

 fourteen inches, and by the greater breadth 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 ^"d 

 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, the 

 species is seldom observed. 



