587 



THE LESSEE BLACK-BACKED GULL. 



LARUS FUSCUS. 



Wings reaching two inches beyond the tail ; head and neck white, streaked (in 

 winter) with brown ; lower parts pure white ; rest of the upper plumage 

 blackish grey ; primaries black, the first two with an oval white spot near the 

 tip ; secondaries and scapulars tipped with white ; bill, irides, and feet, 

 yellow ; tarsus two and a quarter inches long ; orbits red. In young birds 

 the white plumage is mostly replaced by grey mottled with brown, and the 

 black by dusky edged with yellowish ; the primaries liave no white spots, and 

 the bill is dusky. Length twenty-four inches. Eggs brownish grey, spotted 

 with brown and black. 



This is a generally diffused species, occurring in consider- 

 able numbers, not only on various parts of our coast, but 

 in the Baltic, the Mediterranean, the Black Sea, the Eed 

 Sea, and the northern parts of America. It repairs in 

 spring either to rocky islands, steep cliffs, or sometimes to 

 inland lakes, where it builds a rather large nest of tufts 

 of grass, and lays two or three eggs. When the young 

 are hatched it is very impatient of having its stronghold 

 invaded, and resents molestation by darting at the head 

 of the intruder. The Lesser Black-backed Gull breeds 

 habitually on many parts of the coast, especially such as 

 are frequented by the Herring Gull. Its food and habits 

 are much the same as those of the Common Gull. 



THE HERRIJSTG GULL. 



LARUS ARGENTATUS. 



Head and neck white, streaked in summer with light brown ; tail and lower 

 parts white ; back and wings bluish ash ; primaries dusky, passing into black, 

 the shafts black and extremities white ; secondaries edged and tipped with 

 white ; bill, orbits, and irides, yellow ; feet flesh-colour. In young birds the 

 white is mostly replaced by dark grey, mottled with brown ; wings and tail 

 brown, the latter reddish yellow towards the end ; bill dusky ; irides, orbits, 

 and feet, brown. Length twenty-three inches. Eggs olive-brown, spotted with 

 dark brown and dusky. 



If, among a flock of Common Gulls seen either following 

 a vessel at sea or attending on the movements of a shoal 

 of fish, one be observed which greatly surpasses the rest 



