The bill of a male measures 2 inches and 8 twelfths along the ridge, the frontal angles 4 twelfths more; the breadth of the upper mandible at the base is 8-1/2 twelfths, near the end 1 inch and 3 twelfths. The roof of the mouth is broadly and deeply concave, with a prominent median ridge, which becomes papillate towards the base; the edges of the mandible soft, direct, inflected towards the end; lamellæ projecting beyond the margins and tapering to a point. On each side of the lower mandible are about 220 lamellæ, and about 180 on the upper. The tongue is 2-3/4 inches long, deeply emarginate at the base, with numerous papillæ, for half an inch narrow and compressed, then for an inch expanded, with a thin longitudinal flap above on each side divided into lamellæ and minute bristles, at its anterior part having a breadth of 1 inch and terminating abruptly, but with a median thin semicircular tip, which is 3 twelfths long. The œsophagus is 8 inches and 10 twelfths long, 4-1/2 twelfths in diameter, its walls thick. The proventriculus is oblong, 1 inch in length; its glandules of moderate size. The stomach is a strong gizzard of moderate size; the lateral muscles and their tendons large as in all other ducks. The intestine is very long, measuring 8 feet, and very narrow, its diameter being from 2 twelfths to 1-1/2 twelfth, for half its length, after which it enlarges to 3-1/2 twelfths at the distance of about 2 feet from the commencement of the rectum, then gradually diminishes to 2 twelfths. The rectum is 3 inches 2 twelfths long, the cœca 4 inches, their diameter for 1-1/4 inch 1-1/2 twelfth, afterwards 3-1/2 twelfths. The trachea is 6 inches 9 twelfths long, very little flattened, its diameter at the upper part 2-1/2 twelfths, gradually enlarging to 4 twelfths. On the left side of the inferior larynx there is a rounded expansion of very moderate size compared with that observed in many other ducks. The rings are 98; those at the lower part broader and much stronger, but all of them ossified. The bronchial half rings about 35. In another individual, the stomach is 1-1/2 inch long, 1-5/12 broad; the right lateral muscle 6 twelfths thick. Contents, particles of quartz, and fragments of shells. Intestine 11 feet 6 inches long; cœca 6-1/4 inches long; rectum 3-1/2 inches.