216 BONAPARTIAN GULL. 
Young in December. Plate CCCXXIV. Fig. 3. 
Bill greyish-black, iris dark brown ; feet flesh-coloured, claws dusky. 
Head and neck greyish-white ; a small black patch about an inch be- 
hind the eye on each side. Upper parts dull bluish-grey, many of the 
wing-coverts greyish brown, edged with paler; quills as in the adult ; 
rump and tail white, the latter with a broad band of black at the end, 
the tips narrowly edged with whitish. 
Length to end of tail 133, to end of wings 158, to end of claws 13; 
extent of wings 324 inches. Weight 6 oz. 
The white spots on the tips of the wings vary greatly in size, and 
are frequently obliterated when the feathers become worn. 
Palate with five series of small distant papille. Tongue 1 inch 13 
twelfths long, slender, tapering to a slit point, emarginate and pa- 
pillate at the base, horny towards the end. Aperture of posterior 
nares linear, 9 twelfths long. Heart 1 inch long, 9 twelfths broad. 
Right lobe of liver 1 inch 11 twelfths long, the other lobe 1 inch 7 
twelfths. 
The cesophagus is 63 inches long, very wide with rather thin pa- 
rietes, its average diameter when dilated 10 twelfths, within the 
thorax enlarged to 1 inch 2 twelfths. ‘The transverse muscular fibres 
are distinct, the internal longitudinal less so; the mucous coat longi- 
tudinally plicate. The proventriculus is } inch long, with very nu- 
merous small glandules. The stomach is a small oblong gizzard, 10 
twelfths long, 8 twelfths broad ; its lateral muscles rather large, as are 
its tendons. ‘The inner coat or epithelium is of moderate thickness, 
dense, with nine longitudinal broad ruge, and of a brownish-red colour. 
The intestine is 243 inches long, its diameter 2 twelfths. The rec- 
tum is 13 inch long. The cceca are 2 twelfths long, 1 twelfth in dia- 
meter, cylindrical and obtuse. 
The intestine of another individual, a male, is 203 inches long, 3 
twelfths in diameter. 
The trachea is 3 inches 10 twelfths long, its diameter at the top 
3 twelfths, at the lower part 2} twelfths, the rings very feeble, unos- 
sified, about 130 in number. The sterno-tracheal muscles are very 
slender, as are the contractors ; and there is a pair of inferior laryngeals. 
The bronchi are of moderate length, with about 18 half rings. 
