THE RAZOR-BILLED AUK. 
135 
glossed -^ith olive-green, the throat and sides of the neck tinged with 
chocolate, the wings with brown, the tips of the secondary quills, and a 
narrow line from the bill to the eye, white. 
Length to the end of tail 17 inches, to the end of claws 17f ; extent of 
wings 291 ; wing from flexure 8-1 ; tail 4 ; bill along the ridge 1 T \, along 
the edge 2fe, its greatest depth fi ; tarsus l r 2 2 ; middle toe 1 T 3 2 , its claw T 5 2 . 
Weight 11 pounds. 
Adult Female in summer. 
The female is precisely similar to the male. 
The Young in their winter plumage have the colouring distributed as in 
the old birds, but with the black duller, the wings more brown, the throat 
and sides of the head mottled with white, the white line from the bill to the 
eye existing, but the bill much smaller, without furrows or a white line. 
The Old Birds in winter have the throat and sides of the neck mottled 
as described above ; but in other respects their colours are the same as in 
summer. 
The gullet wide, dilated towards the lower extremity, its mucous coat 
longitudinally corrugated ; the proventriculus very wide and glandular ; 
the stomach rather small, oblong, muscular, with an inner, longitudinally 
corrugated and horny cuticular coat. Pylorus very small ; intestine near 
its commencement T 4 2 of an inch in diameter, gradually contracted to the 
cceca, where it is x % ; coeca half an inch long, tapering. The length of the 
gullet and stomach together is 8 , that of the intestines 41 inches. 
On the palate are several series of reversed papillas, and two longitudinal 
papillate ridges ; on its anterior part are-five prominent lines ; the posterior 
aperture of the nares linear, 1 inch in length ; width of mouth 11 twelfths. 
Tongue li inches long, fleshy, slender in its whole length, trigonal, flat 
above, with a median groove, and tapering to a very thin horny point. 
(Esophagus 82 inches long, its width along the neck 10 twelfths, but within 
the thorax it forms an enormous sac 31 inches long, 1 inch 11 twelfths in 
breadth ; the proventricular glands vei'y numerous, forming a complete belt 
3^ inches in length, and occupying almost the whole of the sac above 
mentioned. Stomach very small, 10 twelfths long, 9 twelfths in breadth ; 
its muscular coat thin, the tendons round, and about 5 twelfths in breadth ; 
the epithelium thin, dense, and longitudinally rugous. Intestine 53 inches 
long, its average width 5 twelfths ; the coeca 9 twelfths long, 11 twelfths 
in breadth, 2 inches 1 twelfth distant from the extremity ; cloaca globular, 
and about 1 inch in diameter. 
Trachea 5 inches long, from 41 twelfths to 3 twelfths in width, a little 
flattened ; its rings 95, unossified. Bronchi very wide, of 18 half rings. 
Cleido-tracheal muscles, lateral muscles, sterno-tracheal slips, and a single 
pair of inferior laryugeal muscles. 
