522 



NATATORES. CATARACTES. 



SKUA. 



and mosses, and its two eggs are of a dark oil-green, with 

 irregular blotches of liver-brown. At this season the bird is 

 very courageous, and, like the Common Skua, attacks every 

 intruder upon the limits of its territory, by pouncing and 

 striking at the head with its bill and wings. It also occa- 

 sionally endeavours to divert attention by feigning accidental 

 lameness, in the same manner as the Partridge and Lapwing. 

 Its flight is rapid and peculiar, being performed by succes- 

 sive jerks, which render it easily distinguishable from the 

 Gulls, amongst whom it is so often seen mingled, in watch- 

 fulness of their movements. This species is widely distri- 

 buted throughout the higher Arctic Regions, and was met with 

 in all the late Expeditions to the polar seas, both in Europe 

 and North America. 



General 

 descrip- 

 tion. 



Adult bird. 



PLATE 101.* represents the Arctic Skua of the natural size, 



and in the matured plumage. 



Bill having the cereous part greyish-black, with the tip 

 darker ; depressed, and broad at the base ; grooved as 

 in the Cat. Pomarimts, and forming three plates ; lower 

 mandible laterally grooved for two-thirds of its length ; 

 the symphasis forming a slight angle ; commissure 

 straight to a little beyond the line of the nostrils, when 

 it becomes curved in both mandibles. Irides chesnut- 

 brown. Forehead, chin, cheeks, sides of the neck, and 

 breast, pale straw-yellow. Belly yellowish- white, pass- 

 ing towards the abdomen and upon the flanks into 

 greyish-brown. Feathers of the upper part of the neck 

 wiry and acuminate, forming a kind of collar. Crown 

 of the head, nape of the neck, back, quills, tail, and 

 under tail-coverts, brownish-black, tinged with grey, 

 deepest upon the head and the extremities of the wings 

 and tail. Shafts of the quills and tail-feathers whitish 

 to near their points. The two middle tail-feathers much 

 produced, and tapering to a fine point. Wings, when 

 closed, very little longer than the lateral feathers of the 



