of the United States. S63 



closed posteriorly by the cere : tongue canaliculated, acute, 

 slightly bifid at tip. Head large ; eyes large : neck rather 

 stout : body rather plump. Feet slender ; naked space of 

 the tibia moderate; tarsus equal to the middle toe, scaly 

 behind; webs full, entire; lateral toes edged exteriorly with 

 a narrow membrane; middle toe longest; inner shorter than 

 the outer; hind toe very small, placed almost on a level with 

 the anterior, resting on the ground : nails strong, much in- 

 curved, very acute. Wings moderate, acute ; quills strong ; 

 first primary longest. Tail slightly rounded, of twelve 

 feathers, two middle feathers elongated. 



Female similar to the male. Young differing from the 

 adult, and changing repeatedly. Moult twice in the year 

 without changing their colors. Colors dark brown, with 

 some white or light tints on the neck and beneath. Young 

 more spotted, and with the middle tail feathers hardly longer. 

 Adult eminently distinguished by having these feathers much 

 the longest. 



Bold : fierce : indefatigable. Tyrants of the sea. Soli- 

 tary, seldom several in one neighbourhood. Extremely 

 voracious : feed on fishes, which are caught by other birds. 

 Great enemies to the Terns, Gulls, and even the gigantic 

 Albatros, on which they prey ; attacking them on the wing, 

 and beating them until they drop their prey, or even forcing 

 them to disgorge their food, which they seize in the air with 

 great agility before it reaches the water, the Gulls only escape 

 by settling in the sea. Never diving, only procure themselves 

 floating objects ; feed also on mollusca, eggs, and young 

 water birds. Breed socially in Arctic marshes, on rocks, or 

 among sands: build in tufts with grass: eggs one or two: 

 courageous in behalf of their young ; attacking man himself 

 in their defence. Walk erect. Flight peculiar, irregular, 

 rapid, describing short curves, and occasionally tumbling 

 over. 



Inhabit the Arctic seas all around the globe, migrating but 



