NATURAL HISTORY SOCIETY OF GLASGOW. 207 



Yarrell gives 22 inches in length for one, and for another 18 

 inches; wing, 15| inches. The wings, he says, reached two 

 •inches beyond the tail. 



Richardson and Swainson, F.B.A. 418 : 



Length, 26; extent, 50 inches, 

 — these measurements being copied from Macgillivray, who 

 probably had his specimens from Audubon. 



Audubon, ''Ornith. Biog.," Vol. iii., p. 553 : 



Length, 26; wing, 17J; extent, 50 inches. 



This author describes the angle of the mouth and edges of 

 eyelids as being of an orange red; irides, pale yellow. 



Baird, Cassin, and Lawrence. Birds of North Amer. 843 : 

 Length, 26; wing, 17| inches, 

 — measurements which, when taken in connection with the fact 

 that they give little or no information about this gull, would 

 almost indicate that they had been borrowed, without acknow- 

 ledgment, from the same source. 



The flight of the Iceland Gull, so far as I have observed, 

 resembles that of a large tern — the flapping motion being similar 

 to that of the Common or Arctic Terns, owing, no doubt, to the 

 length of the quill feathers in proportion to the size of the body 

 of the bird. It appears to be a much shyer bird than either the 

 Glaucous or Black-backed Gulls. It is well known in Arctic 

 waters; and, according to Professor Newton, is a winter visitant 

 only to Iceland, while the Glaucous Gull is resident there. 



As in the case of the bird last named, another species closely 

 resembling the Iceland Gull has been discovered on the coasts of 

 North America (Behring's Straits and Greenland), and been named 

 by Bruch L. chalcopterus. This species, which is the Grey-winged 

 Gull of Lawrence, appears to be a small edition of L. glcmcescens, the 

 offshoot from the Glaucous Gull, and is only to be recognised by the 

 ashy grey wing feathers, terminating in Avhite spots at the points. 

 This circumstance is highly curious, though not without suspicion, 

 as the same deviation happening in both forms is apt to create a 

 doubt in the specific value of the eastern bird. Glaucescens is 

 a good species, and appears to be confined to the coasts of North- 

 western America. As, however, the smaller variety has been 

 recognised by Professor Baird and the late Mr Cassin, it would 

 be well to scrutinize carefully all specimens of British killed 

 Iceland Gulls. The unusually large flocks of gulls of all kinds, 



