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 w'ebs 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 
* This 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. 
