216 LONG-WINGED SWIMMERS — LONGIPENNES. 



carcases on the killing-grounds of the fur-seal. At Walrus Island it is resident 

 throughout the season, and lays its eggs in neat nests built of sea-ferns and dry grass, 

 placed among the grassy tussocks on the centre of the island. Though it is some- 

 times driven by the ice to the ojjjen water fifty to a hundred miles south, it returns 

 immediately after the floe disappears. It lays as early as the first of June, deposit- 

 ing three eggs usually within a week or ten davs. These eggs are large, spherically 

 oval, having a dark grayish-brown ground, with irregular patches of darker brown- 

 ish black. They vary somewhat in size, but the sha})e and pattern of coloring is 

 quite constant. 



The young Burgomaster comes from its shell, after an incubation of three weeks, 

 in a pure-white thick coat of down, which is speedily supplanted by a brownish-black 

 and gray plumage, with which the bird takes flight — having at that time nearly the 

 size of the parent-bird. This dark coat becomes within the next three months nearly 

 Avhite, with the lavender-gray back of the adult. The legs change from a pale gray- 

 ish tone to the rich yellow of the mature condition ; and the bill also passes from a 

 dull-brown color to a bright yellow, with red spots on the lower mandible. 



This Gull has a loud shrill cry, which soon becomes very monotonous from its 

 constant repetition. It also utters a low chattering croak while sailing around the 

 islands. It is a very neat bird about its nest, and keeps its plumage in a condition 

 of snowy purity. It is not seen in such large numbers as are several other species. 

 In 1872, when Mr. Elliott visited Walrus Island, he estimated that there were not 

 more than five or six hundred nests. 



The egg of this species exhibits the same variations as to the shades of its ground- 

 coloring as does that of the argentatus — being of a deep brown clay -color, a pale ash, 

 a light pale clay, or a pearly white. The markings, which are small, and iiot very 

 numerous, are deep bistre — almost black. The breadth of the egg is visually relatively 

 greater than in other species. 



Lai'us leucopterus. 



THE WHITE-WINGED GULL. 



Larus argentatus, Sabine, Trans. Linn. Soc. XII. 1818, 540 (not of Brunx. 1764). 



Larus leucopterus, Fabicu, Piodr. Isl. Oni. 1822, 91. — Sw. & KicH. F. B. A. II. 1831, 418. Nutt. 



Man. II. 1834, 305. — Aud. Orn. Biog. III. 1835, 553, pi. 282; Synop. 1839, 327 ; B. Am. 



VII, 1844, 159, pi. 447. — Lawr. in Baird's B. N. Am, 1858, 843. — Baiud, Cat. N. Am. B. 



1859, no. 658. — CouES, Key, 1872, 311; Check List, 1873, no. 544 ; 2d ed. 1882, no. 769 ; B. 



N. W. 1874, 622. — RiDGW. Noin. N. Am, B. 1881. no. 661. 

 Larus arcticus, Macgill. Mem. Wem. Soc. V. 1824, 268. 

 Larus glaucoidcs, "Temm." Mkyeu, Taschenb. Vog. Deutschl. IV. 1822, 197. — Temm. PI. Col, 77e 



livr. Introd. Larus, 1828. 

 Larus ishmdicus, Edmon.st. Mem. Weni. Soc. IV. 1823, 506 (nee op. cit. p. 185 = L. gluucus). 

 Larus minor, Breiim, Viig. Deutschl. 1831, 736. 

 Laroidcs subleucopterus, Buehm, t. c. 746. 

 Larus [Glaucus) glacialis, Brucii, J. f. 0. 1853, 101 (nee Macgill. 1824). 



Hab. Range about the same as that of X. (jlaucus. South in winter to coast of Massachusetts. 



Sp. Char. Similar to L. glaucus, hut much smaller, the young darker colored. Adult, in 

 summer: Mantle pale pearl-blue (a shade darker than in L. glaucus) ; remiges similar, Init slightly 

 paler, passing terminally into pure white. Rest of the plumage snow-white. " Bill bright orange- 

 yellow, tipped with yellowish green ; vermilion spot on lower mandible ; tarsi and toes flesh- 

 color ; iris cream-color" (L. Kumlien, MS.^). Adult, in winter: Similar, but head and neck 



1 " Bill gamboge-yellow, with a spot of orange-red near tlie end of lower mandible ; the angle of the 

 inoutli and the edges of the eyelids are also orange-red. Iris pale yellow. Feet pale flesh-color; claws 

 grayish brown " (Audubox). 



