EGGS OF BRITISH BIRDS. 115 



end. Some specimens are very sparingly marked with a few 

 large blotches here and there. The underlying markings are 

 numerous, large, and very conspicuous, and on some eggs are the 

 preponderating ones, the surface-spots being only represented by 

 a few indistinct blotches or dark brown ^streaks. The eggs vary 

 in length from 2 "25 to 2'0 inches, and in breadth from 1'68 to 1'5 

 inch. The eggs of the Kittiwake are not easily confused with 

 those of any other British species. 



THE IVOKY GULL. 

 (Larus eburneus.)* 



Plate 32, Fig. 3. 



The Ivory Gull is one of the very few birds which are residents 

 in the Arctic regions, and is only a rare straggler to the British 

 Islands. Except perhaps on the icy shores of Greenland, it 

 does not probably breed more than a thousand miles from the 

 North Pole. Within this limit, wherever land has been found, 

 the Ivory Gull has been observed during the breeding-season — ■ 

 in Spitsbergen, Franz-Josef Land, Novaya Zemlya, Bennett 

 Island, Herald Island, the Parry Islands, and Grinnell Land. It 

 generally breeds in colonies on inaccessible cliffs. Dr. Malmgren 

 obtained its eggs in Spitsbergen on the 7th of July, 1861, where 

 it was breeding on the side of a steep limestone precipice several 

 hundred feet high, in company with the Kittiwake and the 

 Glaucous Gull. 



The nests were shallow depressions in the soil, carelessly lined 

 with dead grass, moss, other weeds, and a few feathers. 



The Ivory Gull never lays more than two eggs. The specimen 

 in the Dublin Museum measures 2"45 inches in length, and 1"7 

 inch in breadth ; the ground-colour is huffish-olive, and the 

 surface-markings, which are distributed over the entire shell, are 

 dark brown and pale brown, and the underlying markings, which 

 are very large and conspicuous, are violet-grey. The eggs appear 

 to resemble those of the Kittiwake in colour, but those of the 

 Common Gull in size. 



* Pagophila eburnea — Saunders, Manual, p. 669. 



