Both mandibles are concave within; the palate flat, with two longitudinal ridges; the posterior aperture of the nares linear and 9 twelfths long, the anterior or external aperture _entirely obliterated_. The lower mandible has a distinct oblique joint at about a third of its length, enabling it to be expanded to the extent of an inch and a half. The pouch, which is small, is constructed in the same manner as that of the Pelicans and Cormorants; its muscular fibres running from the lower edge of the mandible downwards and backwards, and a slender muscle passing from the anterior part of the hyoid bone to the junction of the crura of the mandible. The tongue is reduced to a mere oblong knob, 1-1/2 twelfth long, and 1/2 twelfth in height. The aperture of the glottis is 3 twelfths long, with two roundish thin edged flaps behind, destitute of papillæ. There is a small bone appended to the occipital ridge, 1/4 inch in length, as in the Cormorants. The œsophagus _a b_, is 17 inches long, exceedingly delicate and dilatable, with external longitudinal fibres, the transverse fibres becoming stronger towards the lower parts. Its diameter when moderately dilated is 1-3/4 inch at the top, 1 inch farther down, at its entrance into the thorax, 9 twelfths, and finally 1-1/2 inch; but it may be dilated to a much greater extent. _The proventricular glands, instead of forming a belt at the lower part of the œsophagus, are placed on the right side in the form of a globular sac_, about an inch in diameter, communicating with the œsophagus, _b_, and stomach, _d_. For two inches of the lower part of the œsophagus, _b_, or at that part usually occupied by the proventriculus, the transverse muscular fibres are enlarged, and form an abrupt margin beneath; on the inner surface there are four irregular series of large apertures of gastric glandules or crypts. The proventriculus itself, _c_, is composed of large crypts of irregular form, with very wide apertures, and covered externally with muscular fibres. The stomach, _d d_, is roundish, about an inch and three quarters in diameter, with two roundish tendinous spaces, _e_, and fasciculi of muscular fibres; its inner coat thin, soft, and smooth. It opens by an aperture a quarter of an inch in diameter into a small sac, _f_, precisely similar to that of the Pelican, which has a muscular coat, with a soft even internal membrane, like that of the stomach. The pylorus has a diameter of 2 twelfths, is closed by a semilunar valve or flap, and is surrounded by a disk of radiating rugæ three-fourths of an inch in diameter. The intestine, _g h_, is 3 feet 4 inches long, its average diameter 2-1/4 twelfths, but only 1 twelfth at its junction with the rectum, which is 3-1/2 inches long, 3 twelfths in diameter. The cloaca globular, 1-1/2 inch in diameter. There are _no cœca_ properly so called, but a _small rounded termination of the rectum_ 2 twelfths in length as in the Herons. [Illustration]