KITTIWAKE GULL. 85 



the inner primaries, and forming a sub-terminal band on the 

 fourth and fifth, which have white tips, the band on the latter 

 very narrow ; on the sixth the sub-terminal bar is very narrow 

 and often reduced to a spot, and is occasionally entirely absent ; 

 rump, upper tail-coverts, and tail pure white ; head and neck all 

 round also pure white, extending on to the upper mantle ; entire 

 under surface of body pure white ; bill yellow, with a greenish 

 tinge \ tarsi blackish ; toes dark brown. Total length, 16 inches ; 

 oilmen, 1*7; wing, 12*4; tail, 4*75 ; tarsus, 1*45. 



Adult Female. Similar to the male. Total length, 16*0 inches ; 

 wing, 13-0. 



Adult in Winter. Differs from the summer plumage in having 

 the hinder crown and neck washed with the same grey as the 

 back ; in front of the eye a shade of dusky grey, and behind 

 the ear-coverts a patch of blackish, which extends in a feeble 

 degree round the nape, where it nearly forms a collar ; bill more 

 olive. 



Young 1 . Similar to the winter plumage of the adult, but with 

 black mottlings across the hind neck, forming a more or less 

 complete black band ; the marginal wing-coverts and most of 

 the lesser wing-coverts black, forming a band down the wing, 

 which is continued by the black on the outer webs of the inner 

 secondaries ; the primaries with more black on them than in 

 the adults, the inner webs with a long white "wedge," but the 

 black extending along the outer web and for some breadth 

 along the inner edge of the shaft ; the fifth and sixth primaries 

 with a sub-terminal bar of black, represented sometimes on the 

 seventh by a black spot ; tail with a broad black band at the 

 end, decreasing towards the outermost feathers. 



Nestling. Dark grey, more fulvescent on the nape; white 

 below ; toes brown, the webs yellowish. 



Mr. Saunders observes that the birds of Bering Sea and the 

 North Pacific are slightly larger than those of the Atlantic 

 Ocean, and have a " little more development of the usually 

 diminutive hind-toe. Sometimes there is a very minute, but 

 sharply-pointed, nail on each hind-toe, though often on one only. 

 This development is not confined to examples from the North 

 Pacific, for it has been found in birds from the British Islands, 

 Greenland, and the eastern side of North America, 



