I50 GULL GROUP 



mentioned, a much less uncommon visitor than it is to the southern 

 coasts of England ; and its visits to Ireland are only occasional, and 

 then in very small numbers. It is noteworthy that although most of 

 the records arc in winter, specimens of these gulls have been taken 

 in Ireland in every month of the year except July. On the American 

 side of the Atlantic the winter-range extends to the latitude of Boston. 

 In the North Pacific the group is represented by Larus glaucescens, 

 allied to L. hyperboreus, and two smaller species or races. 



As already mentioned, this species differs from the greater white- 

 winged gull chiefly in point of size, males not exceeding 22 inches in 

 length, with a wing which from base to tip does not measure more than 

 i6\i inches, a length exceeded in the smallest individuals of the last- 

 named bird. The legs and the rim of the eyelid are flesh-coloured, and 

 the beak is yellow with a red patch at the angle of the lower jaw. The 

 young resemble those of the greater white-winged gull but are some- 

 what darker ; and similar stages are passed through during the 

 assumption of the adult plumage, which is completed by the end 

 of the fourth year. 



In Scotland these gulls are exceedingly wary and shy ; the)' com- 

 mence their winter-visit to Iceland about the middle of September, 

 and depart northwards in the latter part of April or May. In habits 

 the species appears to be more energetic and active than the greater 

 white-winged gull. The eggs, which are laid at the commencement 

 of June on the bare sand in slight hollows or on cliff-ledges, vary in 

 ground-colour from greenish grey to pale buff, and are generally 

 evenly blotched and spotted with chocolate and blackish brown ; the 

 underlying markings being pale purple. From 2^ to 2^ inches forms 

 the limit of variation in length. 



Great Black- ^^ ^'^^ white-winged group of gulls is represented 

 Backed Gull '" ^^^ British Isles by a larger and a smaller species, 

 (Larus marinus) ^^ there are two representatives differing to much 

 the same extent in point of size of the group 

 characterised by the black back of the adult. There is this important 

 difference between the two groups, namely, that while, as we have seen, 

 both the white-winged species nest only in the far north, the two repre- 

 sentatives of the black-backs breed within the area under consideration. 

 Doubtless, this difference has some connection with the marked difference 

 in the colouring of the two groups, that of the two white-winged kinds 

 being obviously an adaptation to Arctic conditions. Like the greater 

 white-winged species, the great black-back is a native of both coasts of 



