LARID.E THE GULLS AND TERNS. 225 



The great Burgomaster Gull is an Arctic species which occa- 

 sionally visits Lake Michigan in winter. It is the largest of 

 the gulls, excepting only the Black-backed Gull, or "Saddle- 

 back" (L. marinus). 



In Greenland, where it is almost a resident species, a few in- 

 dividuals (chiefly young birds) being seen in the very coldest 

 weather, it is said to pirate upon the eiders (Somateria mollis- 

 sima borealis), often compelling them to surrender the mussels 

 which they have brought up from the bottom of the bays or 

 fiords. There, "the principal breeding place of this gull in the 

 vicinity of Ivigtut is close by the open sea, near the mouth of 

 the fiord, where they congregate in considerable numbers. In 

 August the young birds assemble in the fiord, especially near 

 the narrow channels, as at Karsuk and Ellerslie, and feed dur- 

 ing that month and the next on the berries of Einpetrum ni- 

 grum. At that season they are easily shot, and their flesh is of 

 a very savory flavor. The breasts of the young of all species 

 of gull are eaten here as a delicacy." * 



Larus leucopterus Faber. 



ICELAND GULL. 



Popular synonym. White-winged Gull. 



Larus argentatus SABINE, Trans. Linn. Soc. xii. 1818, 546 (not of BKUXN. 1764). 



Larus leucopterus FABEK, Prodr.Isl. Orn. 1822, 91. Sw. & RICH. F. B.-A. ii, 1831, 418. NUIT. 

 Man. ii, 1831, 305. AUD. Orn. Biog. iii, 1835, 553, pi. 282; Synop 1839, 327: B. Am. vii.1814, 

 159. pi. 447. LAWK, in Baird's B. N. Am. 1858, 843 BAIRD, Cat. N. Am. B. 1859, No. 658. 

 COUES, Key, 1872, 311 ; Chejk List, 1873, No. 544; 2d ed. 1882, No. 769; B. N. W. 1874, 

 622. RIDGW. Noni. N. Am. B. 1881, No. 661; Man. N. Am. B. 1887, 26. B. B. & R. Water 

 B. N. Am. ii, 18S4. 216.-A. O. U. Cheek List, 1886, No. 43. 



Larus arcticus MACGILL. Mem. Worn. Soc. v, 1824,. 68. 



Larus glaucoides "TEMM." METER, Taschenb. Vog. Deutschl. i v, 1822, 197. TEMM. PL Col. 77e 

 livr. Introd. Larus, 1828. 



Larus islandicus EDMONST. Mem. Wern. Soc. iv, 1823, 506 (nee op. cit. p. 185=i. glaucus). 



Larus minor BKEHM, Vog. Deutschl. 1831, 736. 



Laroides subleucopterus BKEHM, t. c. 746. 



Larus (Glaucus) glacialis BKUCH. J. f. 0. 1853, 101 (nee MACGILL. 1824). 



HAB. Range about the same as that of L. glaucus. South in winter' to coast of Massa- 

 chusetts and the Great Lakes. 



SP. CHAR. Similar to L. glaucus, but much smaller, the young darker colored. A dnlt, 

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

 but slightly paler, passing terminally into pure white. Rest of the plumage snow-white. 



* M. CHAMBEELAIN, in The Auk, July 1889, pp. 214-215. 

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