The INCA, or LEADBEATER'S COCKATOO (_Cacatua Leadbeateri_), another species found on the continent of Australia, differs from the bird we have just described in the arrangement of its colours. Its plumage is white, but the forehead, sides of the neck, the middle and under surface of the wings, are of a beautiful rose tint. The crest is magnificent; the individual feathers of which it is composed are bright red at the root, spotted with yellow in the middle, and tipped with white. When this plume is laid back, nothing but the white tips can be seen, but it is no sooner raised than the blazing red appears, and the yellow spots unite themselves into a stripe that renders its appearance still more striking. The spaces around the eyes are light brown; the beak light horn colour; the foot dark brown. The female is somewhat paler on the lower part of the body, and has large yellow spots upon the crest. Gould tells us that these splendid birds are spread over the whole of South Australia, living principally upon the high gum-trees and brushwood near the rivers of the interior. They are found principally near the Darling and Murray rivers, and do not extend as far as the north-western coast. During the breeding season they appear in great numbers in certain localities, and animate the otherwise monotonous forests of the interior. The voice of the Inca cockatoo is more plaintive than that of its congeners, and its scream not so harsh. THE HELMET COCKATOO. The HELMET COCKATOO (_Callicephalus galeatus_) also deserves notice as being the type of a tribe that forms the connecting link between the True Cockatoos and the GERINGEROES or RAVEN COCKATOOS of New Holland. This bird is known by its short vaulted beak, which has a slightly projecting hook on the upper mandible, and by its tolerably strong and rounded tail. The plumage is beautiful and richly marked; the upper part of the body is a dark slate blue, the forehead, cheeks, and crest scarlet; all the feathers, except the primary and secondary quills and the tail-feathers, are slender, and edged with whitish grey more deeply on the upper than on the under part of the body. The female is darker, and almost of a slate colour, the upper surface of the neck and back sprinkled with pale grey, and the rest of the body marked with irregular greyish white stripes. The feathers on the under parts of the body are of a brimstone colour, edged with dusky red. The spaces round the eyes are blackish brown, the beak light horn colour, the feet black and sprinkled with a greyish kind of dust. We have no knowledge whatever of these birds in their native state. Gould tells us that they are found in the woods on the southern coast of Australia, and on some of the neighbouring islands, as also in the northern parts of Van Diemen's Land, where they inhabit the highest trees, and luxuriate upon the seeds of the different kinds of Eucalyptus. [Illustration: THE HELMET COCKATOO (_Callicephalus galeatus_).]