ICELAND GULL 445 



an immature Iceland Gull, swoop to the surface of the dark 

 waters of the Eiver Liffey, Dublin, and swallow foul-looking, 

 floating refuse. Small crabs, fishes, and other marine 

 creatures, grain, and vegetables, are also eaten. 



Nest. As building-sites, exposed ledges of high cliffs are 

 selected. The eggs vary from two to three in number and 

 are greenish-buff blotched with dark brown. 



Geographical distribution. The term * Iceland ' is hardly 

 applicable to this species, seeing that it does not breed 

 in the country which bears its name. Its breeding-home 

 is mainly in Arctic America. Thus it is plentiful in the 

 summer in Jan Mayen Island and in Greenland, and 

 perhaps breeds on the American side of Baffin Bay. On 

 migration in autumn and winter it visits Iceland, the 

 Faroes, Scandinavia, and the sea-board of Western Europe 

 to the coast of France. Along the North American coast 

 the migration-line in winter extends as far South as Boston. 



DESCRIPTIVE CHARACTERS. 



PLUMAGE. Adult male nuptial. Head, neck, breast, 

 abdomen, and tail, white ; back and wings, pale ' french ' 

 grey ; secondaries, tipped with white, forming a wing-band. 



Adult female nuptial. Similar to the male plumage. 



Adult winter, male and female. Differs from the nuptial 

 plumage in that the head and neck are spotted and streaked 

 with pale greyish-brown. 



Immature, male and female. Said to be darker than 

 the immature L. glaucus (Kumlien), but of much the 

 same pattern of plumage, and also passing through similar 

 seasonal 1 changes, maturity being attained in the fourth 

 year. 



BEAK. Yellow, red at the angle. 



FEET. Pale flesh-colour. 



IRIDES. Pale yellow ; margin of eyelids, pale flesh- 

 colour. 



AVERAGE MEASUREMENTS. 



1 I have not as yet seen a pure white phase of plumage immedi- 

 ately preceding maturity, though it seems probable that it is assumed, 

 as in the case of the Glaucous Gull. 



