338 
LARID.^:. 
grassy slopes, freely covered with rocks and large stones, in the 
immediate neighbourhood of sea-cliffs, the birds often forming 
a colony apart from other species. Upon an intruder approach- 
ing one of these colonies, the bird nearest to him will rise and 
circle about his head, calling to wing the whole body, which 
will hurry up and follow him with loud and repeated cries, 
as long as he remains anywhere near. The young very soon 
leave the nest, and run about among the grass and stones, most 
jealously watched over by the old birds, which are far more 
careful of them than of the eggs, becoming much bolder in 
mobbing one who comes too near. Single pairs, however, will 
build wherever they find a place to suit them, affording better 
opportunity for studying their ways than when in a noisy 
colony. In the nesting time the birds have a habit of now 
and then making a rapid downward sweep, and skimming 
very close over the nest, when one has disturbed them by a 
visit of inspection, and is watching from a distance. 
The Lesser Black-backed Gull begins to lay somewhat later 
than the Herring Gull, but the eggs of the two species are 
so much alike that it is next to impossible to identify them 
unless the birds themselves have been seen at the nest. 
Upon the whole, however, the eggs of the Lesser Black- 
backed are rather smaller and more finely spotted ; they are 
also subject to very great variation both in size and colouring, 
and not seldom in shape likewise. The ground colour may be 
either olive brown, olive green, or stone colour, aU of which 
run through an immense variety of shades. Some eggs are 
blotched, others streaked, and others blotched and streaked 
both, the markings being brown and grey of almost every tint ; 
the dark green eggs are not often streaked. Occasionally 
there is a weU-defined zone of confiuent spots of brownish 
grey and intensely deep brown, upon a ground of bluish olive 
green — a very handsome variety. In number the eggs do not 
appear to exceed three, the usual number in this genus. 
The nest is built of dry grass, sea-pink, &c., as mentioned in 
the account of the Common Gull, with sometimes a little wool. 
