LARIN-^E. CATARACTES. 255 



pressed, obtuse, thin-edged. Mouth and digestive organs 

 nearly as in Larus. Tongue broadly channelled above, 

 contracted and induplicate toward the end ; oesophagus very 

 wide ; stomach small, moderately muscular, with dense, ru- 

 gous epithelium ; intestine rather short and wide ; coeca ra- 

 ther long. Eyes rather small ; eyelids feathered, with a 

 bare crenulate margin. Feet of moderate length, rather 

 stout ; tibia bare below ; tarsus moderately compressed, 

 with anterior decurved scutella, the lateral and posterior 

 scales convex so as to be rough to the touch ; hind toe ele- 

 vated, very small, with a rather large, arcuate, acute claw ; 

 anterior toes rather long ; membranes entire ; claws much 

 curved, compressed, acute. Plumage full, close, firm, on the 

 back and wings compact ; wings very long, rather broad, 

 pointed ; tail of moderate length, of twelve rather broad, 

 abruptly rounded feathers, of which the two middle are con- 

 siderably longer than the rest. 



311. CATARACTES SKUA. BROWN or SKUA PIRATE-BIRD. 



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

 and a half; middle tail-feathers scarcely an inch longer 

 than the rest, broad and rounded. Bill and feet black; 

 feathers of the neck acuminate ; the general colour of the 

 upper parts dark greyish-brown, streaked with brownish-yel- 

 low ; primary quills brownish-black, with their shafts and 

 basal parts white, there being a conspicuous patch of that 

 colour on the wing ; tail blackish-brown, white at the base, 

 but that colour not apparent there. 



Male, 22, 52, 15, 2, 2i, 2^, T 5 F . 



The Skua, or Bonxie, as the Shetlanders call him, is sel- 

 dom met with on the coasts of England, or even of Scotland. 

 Considered with reference to his British territories, he appears 

 to be limited almost to the Shetland islands, of three or four 

 hill-tops of which he has taken special possession. According 

 to the accounts of Mr Low, Dr Neill, Captain Vetch, and 

 Dr Edmondston, he is the boldest of all birds, attacking with 

 great fury any person, however armed, that approaches his 

 haunts in the breeding-season. His manner of walking, 

 swimming, and flying, is similar to that of the Gulls, but more 

 vigorous ; his voice a sharp and shrill cry, like that of a 

 young gull. He feeds on fishes, and occasionally young 

 birds, but obtains a great part of his subsistence by harass- 

 ing the larger gulls until he forces them to disgorge part of 



