544 THE BLACK-BACKED GULL. 



Of similar habitat with this last is the White-winged 

 Gull (Larus leucopterus}. Some 24.00 long and 52.00 in ex- 

 tent, and precisely like the former in color, it would seem 

 to be simply a noticeably smaller pattern of the same; and 

 bears even a closer relation to it than does the Ring-bill to 

 the Herring Gull. The White-wing is so nearly the size 

 and color of the last as to be distinguishable from it in 

 flight only by the white primaries. The young are said to 

 be " pale yellowish-brown throughout, faintly mottled with 

 darker, and with primaries dusky at the tips." 



Of course the noisy little Kittiwake (Larus tridactylus) 

 must be here, for it breeds as far south as Bird Rock, in the 

 Gulf of St. Lawrence, and frequents the harbors along the 

 coast of New England in winter. Some 16.50 long and 

 36.50 in extent, with tail slightly forked, and hind toe very 

 short, it has the back and entire wing dark ashy-blue, becom- 

 ing lighter toward the black tips of the primaries. Remainder 

 white; bill yellow, and feet black. Head and neck tinged 

 with ashy-blue in winter. The young are marked with 

 black on the back of the neck, with a line through the 

 wing, outer two-thirds of some four or five primaries, and 

 tip of the tail. The nest is on the rocks. Eggs, 2.22X1.65, 

 yellowish-buff, with round marks of brown or lilac. 



