544 ORNITHOLOGY AND OOLOGY. 



RISSA TBIDACTYLA. Bonaparte. 

 The Kittiwake Gull. 



Larus tridactylus, Linnams. Syst. Nat., I. (1766) 224. Nutt. Man., II. (1834) 

 298. Aud. Birds Am., VII. (1844) 146. 



DESCRIPTION. 



Adult. Head, neck, entire under plOmage, rump, and tail, white ; back and 

 .wings light bluish-gray; the ends of the five outer primaries, and the outer web of 

 the first, black; the fourth and fifth have small white tips; bill greenish yellow; iris 

 reddish-brown ; legs and feet brownish-black, with a green tinge. 



Young. The head is white, marked on the hind head and neck with bluish- 

 gray ; a spot of the same color over the ears ; a narrow crescent of black in front of 

 the eye; wings and shoulders marked with black; primaries black; tail white, with 

 a subterminal black band; bill black; rest of the plumage same as in the adult. 



Length, about seventeen inches; wing, twelve ; tail, five and three-quarters, 

 bill, one and a half; tarsus, one and three-eighths inches. 



flab. Fur countries ; Labrador ; southern coast in winter. 



This species is not common on our coasts through the 

 summer months. Audubon says it breeds -as far south as 

 the island of Grand Menan, off the entrance of the Bay 

 of Fundy ; and it probably also incubates on other islands 

 off the coast of Maine. The nest is composed of sea- 

 weeds, which are arranged in a large pile, and placed on 

 a ledge of rock in a crevice, or on a jutting shelf. This nest 

 is occupied for successive years ; and it receives additions in 

 every season. The eggs are three in number. Their form 

 is usually ovoidal : their color varies from a creamy-drab, 

 with a very slight olivaceous tint, to a delicate gray. On 

 this are scattered blotches of different shades of brown, 

 and obscure spots and blotches of lilac. Of these eggs 

 as of all the eggs of Gulls and Terns it is difficult to 

 give descriptions by which specimens could be identified. 

 The above description, however, answers for all the eggs 

 of this species in my collection. The dimensions vary from 

 2.20 by 1.60 inch to 2.04 by 1.55. 



