276 AVES NATATORES. P LARUS. 



Breeds on the ledges of rocks. Nest constructed of sea-weed. Eggs 

 two or three in number. Food, worms, marine insects, and small fish. 

 Obs. The Winter Gull of English authors (L. hybernus, Gmel.) is 

 this species in its immature plumage. 



297. L. eburneus, Gmel. (Ivory Gull.) Bill strong; 

 bluish gray, the tip yellow : legs black : naked part of the 

 tibia very small : tarsus one inch six lines : membranes of 

 the toes somewhat abbreviated : adult plumage pure white. 



L. ehurneus, Temm. Man. d'Orn. torn. n. p. 769. Sabine in Linn. 

 Trans, vol. xn. p. 548. Edmondst. in Wern. Mem. vol. iv. p. 501. 

 Ivory Gull, Bew. Brit. Birds, vol. n. p. 214. Selb. Illust. vol. n. 

 p. 497. pi. 94*. 



DIMENS. Entire length sixteen inches, (according to Temminck, 

 nineteen inches) : breadth, wings extended, three feet three inches and 

 a half. EDMONDST. 



DESCRIPT. (Adult plumage.) The whole plumage pure white, with- 

 out spots of any kind : bill thick and strong ; deep bluish gray at the 

 base, the rest ochre-yellow : irides deep brown : wings extending an inch 

 and a half beyond the tail: legs black; covered with a rough skin : tibia 

 feathered nearly to the tarsal joint: membranes of the toes short, and 

 slightly hollowed out : claws much hooked. In young birds, the plumage 

 is pale grayish white, more or less spotted and barred with blackish 

 brown ; the tips of the quills, and a transverse bar at the extremity of the 

 tail, of this last colour : bill blackish, the tip yellow : legs blackish gray. 

 (Egg.) Unknown. 



Inhabits the Arctic Regions. A rare and accidental visitant in this 

 country. A solitary individual in its second year's plumage is recorded 

 by Mr. Edmondston to have been killed in Balta Sound, Zetland, Dec. 13, 

 1822. It is now in the Edinburgh Museum. According to Selby, it has 

 been also killed, in an immature state, in the Frith of Clyde. Food, 

 according to Captain Sabine, blubber and the flesh of whales. Nidifica- 

 tion unknown. 



** Large; exceeding twenty inches in length. 



298. L. argentatus, Brunn. (Herring Gull.) Bill 

 yellow : legs livid flesh-colour : tarsus two inches six lines : 

 wings reaching very little beyond the tail: shafts of the 

 primaries black: mantle (in the adult) bluish ash. 



L. argentatus, Temm. Man.d'Orn. torn. n. p. 764. Herring Gull, 

 Mont. Orn. Diet, fy Supp. Bew. Brit. Birds, vol. n. p. 207. 

 Selb. Illust. vol. ii. p. 504. pis. 96, & 96*. 



DIMENS. Entire length twenty-three inches : length of the bill (from 

 the forehead) two inches three lines, (from the gape) two inches nine 

 lines ; of the tarsus two inches six lines ; from the carpus to the end of 

 the wing seventeen inches three lines. 



DESCRIPT. (Adult in winter) Crown, region of the eyes, occiput, 

 nape and sides of the neck, white, with longitudinal streaks of pale brown 

 on the shafts of the feathers : back, scapulars and wing-coverts, fine 

 bluish ash : primaries dusky, passing into deep black towards their extre- 



