Subfamily LARINsE. 



SABINE'S GULL. 

 Xema sabinii (Joseph Sabine). 

 Plate 72. 



This rare Arctic Gull occasionally reaches the British Islands, particularly the 

 shores of the eastern counties of England, most of the birds recorded having been 

 in winter plumage. A few adults in summer dress have been obtained from time 

 to time ; the example from which the drawing in the plate was taken, showing the 

 dark slaty head bordered by a black line, was purchased in the fishing village of 

 Porthgwarra, Cornwall, from Mr. John Jackson, who informed me it had been shot 

 near the Wolf Rock Lighthouse in September 1894. 



Sabine's Gull breeds in the high northern latitudes of the Old and New Worlds, 

 and was first discovered by Captain Sabine, from whom it takes its name. He 

 found the birds, which showed great boldness in defence of their young, breeding on 

 low rocky islands in company with the Arctic Tern. The eggs, placed on the bare 

 ground, were two in number. In ground-colour these are dull brown or olive, with 

 indistinct blotches of darker brown. The food consists of various insects, fish, and 

 crustaceans. 



In winter the ear-coverts and nape retain the dark colour, but the rest of the 

 head is then white. Immature birds have the upper parts dull brownish-grey, with 

 lighter edges to the feathers, while the tail has a dark subterminal band. 



In this species the tail is distinctly forked. 



ROSS'S GULL. 

 Rhodostethia rosea, Macgillivray. 

 Plate 72. 



A specimen of this small and very beautiful species, known also as the Wedge- 

 tailed Gull, is said to have been obtained near Tadcaster, Yorkshire, in December 

 1846, or February 1847. I* inhabits the seas of the Polar regions, and nothing 

 appears to have been known of its breeding habits until Mr. S. A. Buturlin dis- 



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