152 GULL GROUP 



whether the older naturalists were wrong in their identification, or 

 whether the species forming the colony has changed. Apparently 

 the great black-back has at present no known breeding-station on the 

 east coast of Scotland south of the Moray Firth. There is, however, an 

 egg of the larger species in the collection of the British Museum stated 

 to have been obtained from the locality in question ; but it has been 

 suggested ' that the specimen never came from the Bass. Three eggs 

 collected so long ago as 1846, and reputed to be from the Firth of 

 Forth, are undoubtedly great black-backs' eggs, and at the date they 

 were obtained no dealer could have any object in giving them an 

 incorrect locality. On the other hand, a pair of lesser black-backed 

 gulls and their eggs were taken on the Bass Rock in 1867 ; and at 

 the time they were taken, the collector, in referring to the alleged 

 occurrence of the great black-back on the Bass, stated that he had 

 never noticed this species nesting there, and that all the gulls of this 

 group he had observed were of the smaller kind. When a well-known 

 ornithologist visited the Bass Rock in ]\Iay 1863, the gulls on the 

 Rock were the lesser black-backed species, this being decided from the 

 colour of the legs, which in this species are yellow, in the great black- 

 backed gull flesh-colour. 



Attaining, like the greater white-winged gull, a length of some 30 

 inches, the present species may be distinguished from the former by the 

 black or dark slate-colour of the back and wings. The scapular and 

 secondaries are tipped with white, like the primaries ; and, as in the 

 herring-gull, there is a long wedge of grey running down the inner 

 webs of the primaries, the rest of the plumage being white ; while 

 the rim round the eye is red, the beak yellow with a red patch on the 

 angle of the lower jaw, the eye yellow, and the legs and feet flesh- 

 colour. Young birds resemble immature herring-gulls, but have the 

 markings more sharply defined. The adult plumage is probably not 

 attained until the fifth year. The chick is ashy grey above, mottled 

 with blackish brown, but the nestlings show traces of an earlier striped 

 phase ; the breast is tinged with buff, and the abdomen white. 



A large bird of powerful flight, with a peculiar loud croaking or 

 laughing cry of its own, the great black-back is a perfect terror to all 

 creatures weaker than itself, pecking out the eyes of injured or strayed 

 lambs with its cruel beak, and destroying ducklings and disabled water- 

 fowl, and consuming every egg it can find. On this account it is 

 cordially detested by game- preservers as well as b)' the owners of 

 " eider-duckcries " in Iceland and elsewhere. As an instance of its 



* See W. Evans, Proc. Roy. Phys. Soc. Edinhitri^h, vol. xvi. p. 2 (1 905). 



