68 _ BRITISH SEABIRDS. 
As soon, however, as the duties of the year are 
over great numbers of species resort to the sea 
coasts, where, in all districts suited to their require- 
ments, they form one of the most characteristic 
avine features. It is amongst birds of this order 
that the habit of migration is exceptionally pro- 
nounced, some species journeying every year many 
thousands of miles between their summer haunts, 
or breeding grounds, and their winter homes, or 
centres of dispersal. In the present group of birds 
the wings are generally long and pointed, a form 
best adapted for prolonged and rapid flight, whilst 
the legs are usually long—in some species, as, for 
instance, the Black-winged Stilt, exceptionally so— 
enabling the birds to wade through shallows and 
over soft mud and ooze. In some species the feet 
are semi-webbed, as in the Avocets, in others they 
are lobed, as in the Phalaropes. ‘The bill varies to 
an astonishing degree amongst birds of this class, 
and seems specially modified to meet the varying 
methods by which food is obtained. Thus we have 
presented to us the decurved bill of the Curlew 
type, the recurved bill, characteristic amongst others 
of the Avocet or the Godwits, the nearly straight 
bill of such forms as the Oyster-catcher and the 
Phalarope, hard and chisel-like in the former, and 
finely pointed in the latter; then, again, the bill in 
many species is hard and horny, in others it is 
acutely sensitive, full of delicate nerves, as in the 
Snipes and many others. The bill of the typical 
