SABINE'S GULL. 291 



eye), upper part of the throat, and sides of the neck, 

 are white ; crown, nape, and back of the neck, 

 blacKish grey ; back, scapulars, greater and lesser 

 wing-coverts, blackish grey, tinged with yellowish 

 brown, the extremity of every feather varying from 

 greyish white to white, as it approaches the tail ; 

 under part of the throat and upper part of the 

 breast, pale ash-colour; lower breast and all the 

 under plumage white ; shafts of the first six pri- 

 maries brownish black at base, becoming gradually 

 darker towards the extremity, where they are black 

 in the first three, but in the fourth, fifth, and sixth, 

 assimilate in colour to the feather at that part, 

 which is white ; the entire of the outer webs of the 

 first five, black; the inner webs with a broad 

 edging of white, to within from one to two inches 

 of the end, which part is black in the first three, 

 but tipped with white in the fourth and fifth ; in 

 the sixth, the inner web is white, the outer black, 

 excepting for three or four lines from the tip, where 

 it is white, and again, at about an inch from the 

 end, where a white spot of an oval form appears.* 

 Feathers of the tail twelve in number, white with 

 black tips ; in the two shortest the latter colour ex- 

 tends upwards of an inch from the end, in the outer 

 web especially; of the other feathers, the black 



* Tliis marking of the sixth primary is just the opposite of 

 that observed by Mr. Sabine in some mature specimens, in 

 which its prevailing colour was white, " with sometimes a black 

 spot near the end." Dr. Richardson has remarked, in the 

 Faun. Bor. Amer., that this primary is subject to variation. 



