KITTIWAKE GULL. 655 



tubercle without any projecting horny nail or claw, for which 

 reason the species was called tridactylus — three-toed. The 

 whole length is fifteen inches and a half; from the anterior 

 joint of the wing to the end of the longest quill-feather 

 twelve inches. 



The adult bird in winter has the hind neck pale slate-grey, 

 like the back ; the occiput, top of the head, and the region 

 of the ear-coverts streaked with dusky-grey, the other parts 

 as in summer. 



In birds of the previous year there is a dark line down the 

 outer web of the second primary as well as the first, and 

 indications of the same colour on the outer web of the third 

 primary ; the outer primary-coverts have also dark streaks. 



The young of the year have the bill black ; the irides 

 dusky, almost black ; upper part of the head white ; the 

 occiput and nape with a few dusky-grey patches on a white 

 ground; the lower part of the neck behind marked by 

 numerous blackish-grey feathers ; back, scapulars, great 

 wing-coverts, and secondaries, pale slate-grey slightly tipped 

 with brownish-white, which gradually wears off; points of 

 the smaller wing-coverts black, forming a dark bar ; the four 

 outer primaries on each side black on the outer webs, and 

 also in decreasing proportions on the inner w^ebs next the 

 shafts ; tertials pale slate-grey, with a spot of black near 

 the end, the inner broad web margined with white ; upper 

 and under tail-coverts white ; tail-feathers white, barred with 

 black at the end, except the outer tail-feathers on each side, 

 which are the smallest ; chin, neck, breast, and all the under 

 surface of the body pure white ; legs, toes, and membranes, 

 pale brown. 



The downy nestling is white on the head and underparts, 

 with a buff tint on the shoulders and flanks ; back greyish ; 

 bill nearly black ; feet dusky with yellowish webs. 



Varieties of the Kittiwake are very rare ; the Editor is 

 indebted to Mr. E. Hargitt for a perfect albino obtained in 

 Iceland on the 29th September, 1877. 



