brown colour 
fades away from 
/ the head, leav- 
/ ing it entirely 
| white; and so 
ry 
v 
it remains until 
Dy aan? oO 
— 
the following 
spring. 
Gulls are 
useful birds 
ae in two differ- 
os ent ways. In 
the first 
place they are natural scavengers, spending most of their 
time in scouring the sea and the shore for offal, dead fish, 
etc., which they devour in enormous quantities. In the 
second, they follow the plough, just as rooks do, in search 
of wireworms and other mischievous grubs. Several hun- 
dreds of them may sometimes be seen hard at work in a 
single field, and it is impossible to estimate the value of their 
services. 
Most of the gulls nest on ledges high up on the sides of 
rocky cliffs, merely gathering a small 
quantity of sea-weed together to serve 
as a bed for the eggs. The Black- 
headed Gull, however, resorts to inland 
130 
