300 GREAT BLACK-BACKED GULL. 



at least when seen only in flight. It is chiefly seen in 

 pairs in its adult plumage, is a comparatively shy and 

 wary bird, and may be said to be generally distributed 

 around the coasts of Scotland and England after the 

 season of incubation, frequenting estuaries, but sel- 

 dom straying far from the sea or inland along the 

 course of rivers. In Ireland, from all our records, its 

 frequency and habits at this season are nearly similar. 

 In Europe, it has been found on the Italian shores, 

 and in Sweden and Norway, but we have no notice 

 of its abundance or rarity there. Towards the arc- 

 tic circle it becomes rare, but by Audubon is given 

 to North America, breeding on the shores of Labra- 

 dor for an extent of three hundred miles ; in winter 

 the young migrate as far as the Floridas. In Asia 

 or Africa we appear yet to possess no authentic 

 traces of its existence. The Great Black-backed 

 Gull breeds chiefly in marshes, and on the kind of 

 tracts called in the northern islands of Scotland 

 " Holmes," being elevated flats of rather wet muil 

 or muirish meadow ; the low lands about the estu- 

 ary of the Thames being an example of the first, 

 where Mr. Yarrell observes that this bird frequently 

 breeds. In Orkney and Shetland, however, Mr. 

 Hewitson tells us that it breeds in places nearly 

 inaccessible, and in large companies, the space of 

 half an acre supplying in one year no less than 

 sixty dozen of eggs. We have ourselves observed 

 a few pairs breeding on the Bass Rock in the Firth 

 of Forth, and in one or two similarly insulated 

 situations, and the nest was always placed on the 



