Page:The birds of America, volume 7.djvu/27

Rh r along the edge of lower mandible 5^; tarsus f ; middle toe 2i, its claw |f. Weight 3 lbs. 6 oz.

The Adult Female differs from the male in several respects. The former has the whole plumage dark-coloured, whereas the latter has a broad white space on the breast, that colour extending forwards along the sides of the neck, and encircling it about the middle. The feathers of the back are less elongated and pointed, and their lustre is much inferior to that of the male. The dark parts also are more tinged with brown, and most of the smaller wing-coverts are of the latter colour.

Male. As in the Gannets and Pelicans, the cells of the subcutaneous cellular tissue are extremely large and distensile. The mouth is very wide, its breadth being 1 inch 7 twelfths, opening to nearly beneath the posterior angle of the eye. The palate is convex, with two horny thin-edged ridges, and anteriorly a median ridge of the same kind extending to the tip. The posterior aperture of the nares is linear, 14 inches in length. The lower mandible is extremely narrow toward the end, and deeply grooved, with a kind of joint on each side near the base, rendering it capable of being ex- tended to 2 inches 5 twelfths. The tongue is similar to that of the Pelicans, Gannets, and Cormorants, being exceedingly small, 1 twelfths in length, fleshy, flattened, 4^ twelfths in breadth at the base, 2 twelfths at the middle, the tip obtuse. The nostrils, which are situated at the commencement of the groove on each side of the ridge, are so inconspicuous as to be with difficulty detected, being quite linear, 3j twelfths long, and covered above by a mem- branous edge. The aperture of the ear is of moderate size, 3 twelfths in width; that of the eye is inch.

The heart is of an ovate form, broader and rounder than usual, its length 1 inch 4|- twelfths, its breadth 1 inch 2 twelfths. The lobes of the liver are very unequal, the right being 2 inches 1 twelfth long, the left 1 inch 5 twelfths; the gall-bladder oblong, 9 twelfths in length, 5 twelfths in breadth.

The oesophagus, a b c, is 11^ inches long, at the commencement 2 inches in width, presently contracting to 1 inch 9 twelfths, at the lower part of the neck expanded to 2 inches, within the thorax 1 inch 4 twelfths; the proven- triculus, b c, 1 inch 5 twelfths, its belt of glandules complete, 1 inch 2 twelfths in breadth, 7 prominent rugse. The stomach, c d, is very small, roundish, 1 inch 4 twelfths in diameter, considerably compressed; its mus- ular coat very thin, consisting of a single series of fasciculi; the tendons circular, inch in diameter; its inner coat soft and corrugated, several of the proventricular rugse running down upon it. The walls of the oesophagus are of moderate thickness, the external transverse fibres distinct, the inner coat longitudinally plaited. The stomach differs from that of all the other