AMERICAN RING PLOVER. 579 



epithelium with 24 longitudinal rugae. Intestine 12 inches long, nar- 

 row ; the duodenum 1^ twelfth in width, the rest uniform, the rectum 

 only being a little enlarged. Cceca 1 inch 1 twelfth from the extre- 

 mity, 1 inch 2 twelfths in length, and | twelfth in breadth. Trachea 

 1 inch 10 twelfths long. If twelfth in breadth, contracting to 1 twelfth ; 

 its rings about 70, cartilaginous. Bronchial half rings about 15. Mus- 

 cles as in the last species. Male. 



AMERICAN RING PLOVER. 



Charadrius semipalmatus, Bonap. 



PLATE CCCXXX. Vol. IV. p. 256. 



Width of mouth 2 twelfths. Tongue 4 twelfths long, very con- 

 cave above, rounded at the point. (Esophagus 2 inches 8 twelfths 

 long, 3 twelfths in breadth. Proventriculus 3^ twelfths broad, its 

 glandular belt 6 twelfths. Stomach oblong, 9 twelfths by 7 twelfths ; 

 its muscles large ; the epithelium with numerous ruga?. Intestine 14 

 inches long, 2 twelfths in breadth. Coeca 1 inch from the extremity, 

 1^ inch long, li twelfth in width. Trachea 2 inches long, 1^ twelfth 

 in breadth ; its rings about 70, very feeble. Bronchial half rings about 

 15. The muscles as in the last species. 



In the genus Charadrius, the oesophagus is thus narrow or of mo- 

 derate width, without crop or remarkable dilatation. The proventri- 

 culus is large, bulbiform, with very numerous small cylindrical glands 

 disposed in a broad belt. The stomach is roundish or broadly ellipti- 

 cal, moderately compressed ; its lateral muscles large, as are the ten- 

 dons ; the lower muscle prominent and thin ; the upper of consider- 

 able size ; the epithelium dense, and longitudinally rugous. The in- 

 testine is rather long, and of moderate width ; the rectum considerably 

 dilated ; the coeca long, very slender, cylindrical, contracted at the base, 

 with the tip blunt. The lobes of the liver are very unequal, the right 

 being largest ; there is no gall-bladder. The trachea is rather wide, 

 flattened; its rings very numerous, narrow, cartilaginous, the lower 

 ring large ; two dimidiate rings. Bronchi rather wide, of from 15 to 

 20 half rings. Lateral muscles moderate, sending a slip to the last 

 dimidiate ring. 



