160 ANHINGA OR SNAKE-BIRD. 
The subcutaneous cellular tissue is largely developed, and the lon- 
gitudinal cells on the neck are extremely large, as in Gannets and 
Herons. The olfactory nerve is of moderate size, and the nasal cavity 
is a simple compressed sac 4 twelfths in its greatest diameter. The 
external nares are closed, and there are no supraorbital glands. ‘The 
external aperture at the ear is circular, and not more than half a 
twelfth in diameter. 
The trachea is 133 inches long, much flattened, narrow at the up- 
per extremity, where it is 21 twelfths in breadth, enlarging gradually 
to 44 twelfths, and toward the lower larynx contracting to 2} twelfths. 
The rings are very slender, unossified, and feeble ; their number 230; 
the bronchial half-rings 25. The contractor muscles moderate ; ster- 
no-tracheales ; and a pair of inferior muscles going to the last ring. 
Ina young bird scarcely two days old, and measuring only 32 inches 
in length, the two most remarkable circumstances observed refer to 
the nostrils and stomach. The posterior or palatal aperture of the 
nares is of the same form, and proportional size, as in the adult; the 
nasal cavity is similar; but there is an external nasal aperture, or nos- 
tril, on each side, so small as merely to admit the mystachial bristle of 
a Common Squirrel, The stomach is of enormous size, occupying 
three-fourths of the cavity of the thorax and abdomen, being 10 twelfths 
of an inch long, and of an oval shape. The proventriculus is sepa- 
rated from the stomach and formed into a roundish lobe, as in the old 
bird; and beside it is the lobe or pouch appended to the stomach, and 
from which the duodenum comes off. Even at this very early age, the 
stomach was turgid with a pultaceous mass apparently composed of 
“macerated fish, without any bones or other hard substances intermixed. 
Here then we have an instance of external nares in the young of a 
bird in which they are entirely obliterated in the adult. 
