Feet. In. Length from base of bill to the extremity of the tail 2 6 Length of the bill 4½ Depth of the base of the bill 1⅞ Length of the tail 9 Length of ditto, exserted from feathers of the urupigium 5 Length of the thigh 6½ Length of the tarsus 3 Length of the middle phalanges 5⅛ Breadth of the wings expanded 7 0 Breadth between the wings from the first joint 4 Length of the first joint of the wing 10 Length of the second joint of the wing 10⅛ Length of the third joint of the wing 4 Length of the fourth, or pen-feathers 1 4 Length of inner angle of eye to base of beak 1⅔ Breadth of the foot when expanded 5 First pen-feather the longest. The following is the general description of this species:—The head, neck, breast, and urupigium of a snowy white colour; back, dark lead colour, shaded off to a lighter tint towards the neck; wing coverts, and upper part of the wings and pen-feathers, brownish black; under surface of the wings of a white colour, intermingled with light brown, (forming a white streak, extending the whole length on the under surface,) except the pen-feathers which are the same colour above as beneath; tail, dark lead colour, of a lighter tint on the under surface; irides, light brown; a black mark on the upper and inner part around the eye, lightly shaded off towards the base of the bill; eyelids black; bill yellow, with the tips of the mandibles, especially the upper one, of a reddish colour, shaded with black; a black narrow membrane extends around the base of the bill, forming a distinguishing character in this species; feet bluish, with the web of a bluish brown colour.