456 AMERICAN ANHINGA. 



with external longitudinal fibres, the transverse fibres becoming stronger 

 towards the lower parts. Its diameter when moderately dilated is If inches 

 at the top, 1 inch farther down, at its entrance into the thorax, 9 twelfths, 

 and finally 1^ inches; but it may be dilated to a much greater extent. The 

 proventricular glands, instead of forming a belt at the lower part of the 

 oesophagus, are placed on the right side in the form of a globular sac, 

 about an inch in diameter, communicating with the oesophagus, b, and 

 stomach, d. For two inches of the lower part of the oesophagus, 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,y^ 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 rugas 

 three-fourths of an inch in diameter. The intestine, g h, is 3 feet 4 inches 

 long, its average diameter 2\ twelfths, but only 1 twelfth at its junction with 

 the rectum, which is 3^ inches long, 3 twelfths in diameter. The cloaca 

 globular, 1^ inches in diameter. There are no cceca properly so called, but 

 a small rounded termination of the rectum, 2 twelfths in length, as in the 

 Herons. 



The subcutaneous cellular tissue is largely developed, and the longitudinal 

 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 com- 

 pressed sac 4 twelfths in its greatest diameter. The external aperture at the 

 ear is circular, and not more than half a twelfth in diameter. 



The trachea is 13|- inches long, much flattened, narrow at the upper 

 extremity, where it is 2\ twelfths in breadth, enlarging gradually to A\ 

 twelfths, and toward the lower larynx contracting to 2\ twelfths. The 

 rings are very slender, unossified, and feeble; their number 230; the bron- 

 chial half-rings 25. The contractor muscles moderate; sterno-tracheales; 

 and a pair of inferior muscles going to the last ring. 



In a young bird scarcely two days old, and measuring only 3|- 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 



