Bill and legs reddish brown: tarsus one inch seven lines: shafts of the outer primaries white: in summer, a brown hood reaching to the occiput.
L. capistratus, Temm. Man. d'Orn. torn. ii. p. 785. Flem. Brit. An. p. 142. Yarr. in Proceed, of Zool. Soc. 1831. p. 151. Masked Gull, Shaw, Gen. Zool. vol. xiii. p. 204.
Entire length fifteen inches: length of the bill (above, from the first feathers) one inch and half a line, (from the gape) one inch ten lines; of the tarsus one inch seven lines; of the middle toe, nail included, one inch six lines; from the carpus to the end of the wing eleven inches eight lines. Yarr.
(Winter plumage). According to Temminek, exactly similar to that of the next species, from which however the present may always be distinguished by its smaller size, its more slender as well as shorter bill, shorter tarsi, and smaller feet: the colour of the feet is also reddish brown. (Summer plumage). " Head, and upper part of the neck, brocoli-brown, bounded by blackish brown, descending lowest at the fore part, some of the dark feathers at the margin in front tipped with white; the remaining portion of the neck, breast, abdomen, vent and tail, pure white: upper surface of the wings pale ash-gray; under surface grayish white: primaries white, edged and tipped with black, broadest on the inner web; shafts white: bill, legs, and toes, brownish red; membranes chocolate-brown." Yarr. (Egg). Unknown.
But little is known of the habits of this species, which was first characterized as distinct from the two following, by Temminek. Inhabits the Shetland and Orkney Islands. Has been also shot in Ireland, in the neighbourhood of Belfast, by Mr Thompson. Food and nidification unknown.