THE GREAT BLACK-BACKED GUEL. 547 



or mottled with brownish gray, — most heavily on crown, back, wings and tail; 

 bill flesh-colored tipped with black. Second year young are nearly pure white, 

 but show the black-tipped bill. Length 24.00-26.00 (609.6-660.4) ; wing 16.00 

 (406.4) ; tail 6.00 (152.4) ; bill 1.65 (41.9) ; depth of bill at angle of gonys .62 

 (15.8); tarsus 2.20 (55.9). Dimensions quite variable. Specimens apparently 

 intermediate between this species and L,. glaucus are to be found. 



Recognition Marks. — Brant size ; general white appearance ; pale pearl-gray 

 of mantle scarcely distinguishable at a distance; primaries without black. 



Nesting. — Does not breed in Ohio. Nest, on sarudy beaches or rocky cliffs. 

 BggSj 2 or 3, yellowish or brownish buff, marked irregularly with chocolate. Av. 

 size, 2.80 X 1.90 (71. 1 X 48.3). 



General Range. — Arctic regions, south in winter in North America to Massa- 

 chusetts and the Great Lakes, occasionally much further south. 



Range in Ohio. — "Rare winter visitor on Lake Erie" (Wheaton, fide Mr. 

 Winslow). A specimen taken at Lorain, Dec. 22, 1888, by Mr. L. M. McCormick, 

 now rests in Oberlin College^ Museum. 



THE term Iceland, as applied to this Gull, must be understood in a 

 general sense. It accurately describes the sort of country which the bird 

 frequents, the ice-bound shores of the high Arctics, but is not restricted to 

 the political division which bears the name "Island," or Iceland. Indeed, 

 an old observer, Faber, expressly states that this Gull does not breed in Ice- 

 land, where it is abundant in winter, but proceeds in spring much further 

 north. 



The White-winged Gull has in a measure escaped particular scrutiny, 

 because of its close resemblance to the better known Burgomaster, or Glau- 

 cous Gull, of which it is, in fact, a smaller edition. In point of size, also, 

 it is comparable to the Herring Gull, and on this account, birds seen on Lake 

 Erie have doubtless occasionally been allowed to pass for the more familiar 

 species. Like the Burgomaster again the smaller bird is something of a 

 tyrant, quarrelsome and predacious. Not content with catching its own 

 cod-fry, it seizes impudently upon the catch of the more successful and better- 

 mannered birds, and wrests it away in triumph. 



No. 261. 



GREAT BLACK-BACKED GULL. 



A. O. U. No. 47. Larus marinus Linn. 



Synonyms. — Saddle-back ; Coffin-carrier. 



Description. — Adult: Mantle dark slate (black only by courtesy) ; the pri- 

 maries mostly black and tipped (the first broadly) with white^; the secondaries 

 and tertiaries broadly tipped with white; entire remaining plumage white; bill 



1 There exists in each of the outer primaries evidence of a forn\er (or at least suggested) second sub- 

 terminal white band in the shape of a whitish area on the shaft, even amidst the contrasting black of the 

 webbing. On this supposition, the terminal area of the first primary corresponds with the (indicated) sub- 

 terminal bands of the remaining quills. 



