GAME BIRDS, GULLS, ETC. 207 
‘British species, which may be seen in numbers in 
most parts of the shore. 
A curious fact concerning this gull is the difference 
between its summer and winter plumage, which is so 
striking that the two forms of the bird have often 
been considered as constituting two distinct species. 
The Black-headed Gull, 
This difference lies in the head and the upper part 
of the neck, which, during the spring and summer 
months, are of a dark brown colour, so deep, indeed, 
as to be easily mistaken for black at a little distance. 
From this peculiarity, of course, the bird has obtained 
its popular title. At the approach of winter, how- 
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