The wary curlew, already referred to, is really a moorland 
bird, but spends the autumn and winter by the shore, or on 
the mud-flats of estuaries. His peculiar cry, a shrill “‘ cour- 
lie,’ readily distinguishes him. Added to this is his large 
size, brown coloration, and long curved beak. On the wing, 
the rump and upper tail-coverts are conspicuously white. 
” 
The “‘ waders,’ sometimes collectively referred to as the 
“ plover-tribe,”’ are represented in the British Islands by a 
very long list of species, of which only the commonest are 
mentioned here. Many, however, are mere casual visitors. 
Near allies of this ‘tribe’ are the gulls and terns. The 
peculiarly graceful, elastic flight of these birds surely needs 
no description. Even town-dwellers know them well. For 
during the winter months they follow the rivers far inland. 
Even in grimy London they may be seen in hundreds during 
the winter months. The black-headed gull is by far the 
commonest of these winter visitors. But at the same time, 
to the uninitiated, the name ‘“ black-headed’’ must seem 
singularly inappropriate ; for its head is emphatically white. 
At no time, indeed, is it ever black. But keep careful watch 
of the hosts which throng the river from January onward, 
till they depart for their breeding quarters, and you will see 
them gradually developing a dark patch on each side of the 
head. And this slowly spreads till the whole head is of a 
dark, sooty-brown. Immature birds may be picked out by 
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