numbers cross over from our 
southern coasts to the Continent 
during the winter, and are re- 
placed by others which come in 
from farther north. They are 
very indifferent nest-builders, 
and always take advantage, if 
possible, of the deserted abode of 
a Magpie, a pigeon, or a crow. 
And when they bring up their young, as they are fond 
of doing, on a rocky ledge, they make no attempt at a 
nest at all. 
