_Cacatua galerita_, Vieill. 2nde Edit, du Nouv. Dict. d’Hist. Nat., tom. xvii. p. 11; and Ency. Méth. Orn., Part III. p. 1414.—Wagl. Mon. Psitt. in Abhand., p. 695. _Plyctolophus galeritus_, Vig. and Horsf. in Linn. Trans., vol. xv. p. 268.—Vig. in Lear’s Ill. Psitt. pl. 3.—Steph. Cont. of Shaw’s Gen. Zool., vol. xiv. p. 108. _Cacatua chrysolophus_, Less. Traité d’Orn., p. 182. _Car’away_ and _Cur’riang_, Aborigines of New South Wales. _Mangarape_, Papuans of New Guinea. If we regard the White Cockatoo of Van Diemen’s Land, that of the continent of Australia, and that of New Guinea as mere varieties of each other, this species has a more extensive range than most other birds. It is an inhabitant of all the Australian colonies, both on the southern and northern coasts, but has not yet been observed on the western. On a close examination of specimens from the three countries above mentioned, a decided difference is observable in the structure of the bill, but of too trivial a character, in my opinion, to warrant their being considered as distinct; in fact, it would seem to be merely a modification of the organ for the peculiar kind of food afforded by the respective countries. The Van Diemen’s Land bird is the largest in every respect, and has the bill, particularly the upper mandible, less abruptly curved, exhibiting a tendency to the form of that organ in the genus _Licmetis_: the bill of the New Guinea bird is much rounder, and is, in fact, fitted to perform a totally different office from that of the White Cockatoo of Van Diemen’s Land, which I have ascertained, by dissection, subsists principally on the small bulbs of the terrestrial _Orchidaceæ_, for procuring which its lengthened upper mandible is admirably adapted; while it is more than probable that no food of this kind is to be obtained by the New Guinea bird, the structure of whose bill indicates that hard seeds, nuts, &c. constitute the principal part of its diet. The crops and stomachs of those killed in Van Diemen’s Land were very muscular, and contained seeds, grain, native bread (a species of fungus), small tuberous and bulbous roots, and, in most instances, large stones.