the bill is opened, the crura of the lower mandible separate from each other to a considerable extent, by the action of the muscles inserted into their base, this depending upon their oblique position, and the sac is expanded. The upper mandible is capable of being moved to a considerable extent. Below the anterior angle of the eye is a small sac about 5 twelfths of an inch in length, with an external aperture of 2 twelfths, and filled with a pulpy substance. The nostrils are linear, about 3 twelfths of an inch long, and quite concealed by the wrinkles of the skin. The aperture of the posterior nares 8 twelfths. The tongue is an extremely small, papilliform body, 3-1/2 twelfths of an inch long, and 1 twelfth in diameter. The aperture of the glottis is linear, 8 twelfths in length, destitute of papillæ behind. [Illustration] The pharynx is about 2-1/2 inches in breadth. The œsophagus _a_, at the commencement, or opposite the tongue, has a diameter of about 6 inches, and contracts until the middle of the neck, where it is 3 inches in width; at its entrance into the thorax at _b_ it contracts to 1-1/2 inch, but is dilatable to 3 inches; at this part, its inner coat is thrown into very prominent longitudinal rugæ. The structure of the œsophagus is similar to that of the Loon already described, but its muscular coat is much thinner. On entering the thorax, it again expands to a diameter of 3 inches. Its length from the glottis, exclusive of the proventriculus, is 2 feet. The proventriculus, _cd_, when not extended, has a diameter of 2 inches, its length being 4 inches and 8 twelfths. It is marked internally with six longitudinal broad ridges, about half an inch in breadth, and separated by grooves; and its cuticular lining is 1-1/2 twelfths thick, of a compact but soft texture, elevated into tortuous reticulated ridges. The glandules, which are cylindrical, the largest 3 twelfths of an inch long, 1/2 twelfth in diameter, form a complete elongated belt. The muscular coat is also very thick, its inner layer composed of transverse, its outer of longitudinal fibres, and the greatest thickness of the walls of the proventriculus is about 4-1/2 twelfths of an inch. The stomach, _e_, properly so called, is extremely small, being of a roundish, compressed form, 1-1/4 inches in length, and of the same breadth; its muscular coat composed of slender fasciculi, and not presenting a distinction into lateral and inferior muscles, its inner coat smooth. Appended to it on the right side is a sac _f_, of a roundish form, 1-9/12 inch in length, and 1-1/2 in breadth, joining it by a contraction, of which the diameter is 1/2 inch, and opening directly into the proventriculus, as well as into the stomach; its walls thin, its inner surface smooth, with numerous mucous crypts irregularly disposed. The pylorus, _g_, is exceedingly small, 1-1/2 twelfths in diameter, with a thickened margin.