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Subfamily STERCORARINjE. 



Genus STERCOPAPJUS. 



Stercorarius, Brisson, Orn. vi. p. 150 (1760). 



Larus apud Linnaeus, Syst. Nat. i. p. 226 (1766). 



Cataracta apud Fabricius, Faun. Grcenl. p. 103 (1780). 



Catarractes apud Pallas, Zoogr. Rosso- As. ii. p. 309 (1811). 



Lestris apud Illiger, Prodromus, p. 273 (1811). 



Megalestris apud Bonaparte, Cat. Parzud. p. 11 (1856). 



Buphagus apud Coues, Proc. Acad. Nat. Sc. Philad. 1863, p. 125 (ex Moehring). 



Although allied to the Gulls, the Skuas differ sufficiently to justify their being placed in a 

 distinct subfamily. They inhabit the northern and southern portions of the globe, breeding in the 

 far north of both the Old and the New World, and also in the Antarctic regions, but wandering 

 tolerably far from their summer haunts in the autumn and winter. They differ materially from 

 the Gulls in their habits, being bold and predatory, and gain their livelihood chiefly by levying 

 black mail on their weaker neighbours ; for they make a practice of attacking the Gulls and 

 Terns and forcing them to give up the food they have obtained, on which they immediately 

 pounce. They swim and fly like the Gulls ; but their flight is more powerful and vigorous. 

 They not only devour fishes, but will also eat small mammals, the young and eggs of other birds ; 

 and the smaller species are said to eat insects, small crustaceans, and even berries. They either 

 make a nest of seaweed and grass, or else only make use of a depression in the moss, and deposit 

 pale olivaceous or olivaceous-brown eggs blotched and spotted with dark brown. . 



Stercorarius parasiticus, the type of the genus, has the bill shorter than the head, rather 

 broader than high at the base, compressed towards the end, the upper mandible cerate, the tip 

 strongly hooked ; nostrils linear, oblong, in about the centre of the bill ; lower mandible with the 

 crura broad, the angle somewhat prominent, the tip compressed ; wings long, pointed, the first 

 quill longest ; tail moderately long, rounded, except the two central feathers, which are much 

 elongated; feet moderate, strong, the tibia bare for a short distance; tarsus rather slender, 

 scutellate; hind toe small; anterior toes moderately long, joined by webs; claws strong, curved, 

 acute, that on the middle toe with the inner edge slightly dilated. 



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