479 



LESTRIS CATARRACTES. THE COMMON SKUA. 



SKUA GULL. BONXIE. 



Larus Catarractes. Linn. Syst. Nat. I. 226. 



Larus Catarractes. Lath. Ind. Ornith. II. 818. 



Skua Gull. Mont. Ornith. Diet. 



Stercoraire Catarracte. Lestris Catarractes. Temm. Man. d'Omith. II. 729. 



IIL 494. 

 Common Skua. Cataractes vulgaris. Selby, Illustr. II. 514. 

 Cataracta Skua. Bonap. Comp. List, 63. 



Bill two inches and a quarter in length, tarsus two inches 

 and a half, rough behind, with small prominent scales ; 

 middle tail-feathers scarcely an inch longer than the rest, broad 

 and rounded. Adult with the bill and feet black, the feathers 

 of the neck acuminate; the general colour of the upper parts 

 dark greyish-broivn, streaked ivith brownish-yellow ; primary 

 quills hrownish-black, loith their shafts and basal parts white, 

 there being a conspicuous patch of that colour on the wing ; tail 

 hlackish-brown, white at the base, but that colour not apparent 

 there. 



Adult in Summer, — This bird approaches in size to the 

 Herring Gull ; but is of a more compact and robust form, 

 having the body full, the neck of moderate length, the head 

 large, broadly ovate, anteriorly narrowed. 



The bill is shorter than the head, very stout, nearly as 

 broad as high at the base, compressed toward the end, straight, 

 with the tip decurved ; the upper mandible with the dorsal 

 line straight to the end of the cere, then much decurved, the 

 ridge broad and rounded, with a shallow groove on each side, 

 the nasal space covered by a thin plate, the sinus very short, 

 broad, and feathered, the branches narrow and convex, the 

 edges sharp and inflected, the tip very strong, laterally con- 



