74 ALLEN'S NATURALIST'S LIBRARY. 



Adult Male. General colour above delicate pearl-grey ; the 

 wing-coverts like 'the back ; the secondaries and scapulars 

 plainly tipped with white, forming a bar across the wing ; 

 bastard-wing and primary-coverts pearly-grey, the outer ones 

 white ; primaries blackish, with a small white tip and a broad 

 sub-terminal bar of white on the two outermost ; the first 

 primary with a grey base to the inner web, much more extended 

 at the base of both webs in the second primary, and gradually 

 extending on the other quills till they are almost entirely grey, 

 with a black sub-terminal bar before the black tip ; the inner 

 primaries arid all the secondaries grey with a white tip ; rump, 

 upper tail-coverts, and tail pure white ; head and neck all 

 round, as well as the under surface of the body, pure white, 

 including the under wing-coverts and axillaries ; quill-lining 

 dusky-grey, lighter grey towards the base, and with the same 

 pattern of white sub-terminal bars as the upper surface ; " bill 

 greenish-yellow at the base, rich yellow terminally ; tarsi and 

 toes greenish-yellow ; iris golden-brown ; orbital ring ver- 

 milion " (Sounders). Total length, 1 8 inches; oilmen, 1*5; 

 wing, 13*6; tail, 5 '4; tarsus, 2*1. 



Adult Female. Similar to the male, but smaller. Total 

 length, i yo inches; wing, 12 '8. 



Adult in Winter Plumage. Similar to the summer plumage, 

 but with the head and neck streaked with ashy-brown, and 

 with the tarsi and toes olivaceous. 



Young. Brown above, with white or buff bars and margins 

 to the feathers ; under surface of body white, mottled with 

 brown or ashy-brown. The young bird thus resembles the 

 immature Herring-Gull, and is of the same pale colour. It 

 is, however, easily recognisable from the young of the latter 

 species, as well as from that of the Lesser Black-backed Gull, 

 by its smaller size. The young birds go through similar 

 changes of plumage to those of the allied species of Gull, and 

 Mr. Saunders says that the bird only gains its fully adult livery, 

 and breeds, when nearly three years old. 



Characters. In its light pearly-grey mantle and back, the 

 Common Gull resembles the Herring-Gull, but can always be 

 told by its smaller size, the wing never exceeding 16 inches in 



