WHITE-WINGED GULL. 567 



Male in Winter. — This Gull, somewhat inferior in 

 size to Larus argentatus, but in proportion and colour 

 extremely similar to Larus glaucus, to which it bears the 

 same relation, in both respects, as Larus flavipes bears to 

 Larus marinvis, was first made known as a British bird by 

 Dr. Edmondstoii, who obtained specimens of it in Shetland. 



The bill is shorter than the head, stout, compressed, 

 shghtly higher toward the end than at the base ; the upper 

 mandible with the dorsal lines nearly straight for half its 

 length, arcuato-declinate toward the end, the ridge convex, 

 narrow before the nostrils, the sides rapidly sloping and very 

 slightly convex, the edges sharp, direct, toward the end 

 arcuato-declinate, the tip narrow and rather acute ; the lower 

 mandible with the angle long and narrow, the outline of the 

 crura nearly straight until near the angle, which is moderately 

 prominent, the dorsal line ascending and very slightly con- 

 cave, the sides nearly erect and somewhat convex, the edges 

 sharp and slightly inflected, the tip narrow but obtuse. 



The nostrils are linear-oblong, wider anteriorly, nearly 

 five-twelfths of an inch long, medial, nearer the margin. The 

 eyes are rather small, their aperture four-twelfths. The feet 

 are short and slender ; the tibia bare for ten-twelfths of an 

 inch ; the tarsus slender, compressed, with twenty-two scu- 

 tella ; the hind toe elevated, very small, "with two scutella, 

 the second with twenty-four, the third with thirty-four, the 

 fourth with thirty-two ; the edges of the webs are very con- 

 cave, the soles flat, the margins of the lateral toes expanded. 

 The claws are small, slightly arched, compressed, obtuse, 

 that of the middle toe with the inner edge expanded and 

 thin. 



The plumage is full, close, elastic, very soft, on the back 

 and wings somewhat compact. The wings are very long, 

 and reach, when closed, to the end of the tail ; the first quill 

 longest, the second slightly shorter, the rest rapidly graduated ; 

 the secondaries, twenty-four in number, broad, narrowly 

 rounded at the end. The tail is rather short, even. 



The bill is wine-yellow, the lower mandible with an orpi- 

 ment patch near the end ; the edges of the eyelids yellow ; 

 the feet pale flesh-coloured, the claws greyish-brown ; the 



