132 



MARSH OR GULL-BILLED TERN. 



a 



A female from the Mouths of the Mississippi, April 1. 1837. On 

 the roof of the mouth are three 

 longitudinal ridges ; the posterior 

 aperture of the naxes is linear, 

 with an anterior slit ; the tongue 

 slender, tapering, 1 inch 2 twelfths 

 long, papillate at the base, the 

 outer papilla on each side larger, 

 the tip sharp and horny. The oeso- 

 phagus, a 5 c, is 5 inches long, very 

 wide, its greatest diameter 9 

 twelfths. The stomach, ode, is ob- 

 long, 1 inch 2 twelfths in length, 10 

 twelfths in breadth ; its lateral 

 muscles moderate. Its contents 

 are coleopterous and hymenopte- 

 rous insects, together with small 



crabs. The epithelium is thick, 



strong, prominently rugous, of a 



reddish-brown colour, and exactly 



resembling that of the smaller 



Gulls. The proventricular glan- 

 dules are very small, and form a 



belt \ inch in breadth. The intes- 

 tine, fg h i, which is 1 foot 8 inches 



long, is wide, its average diameter Ji 



being 4i twelfths. The coeca, 



which come off at the distance of 



2 inches from the anus, are very 



small, being 3 twelfths long, and 1 



twelfth in diameter. 



The trachea is 4 inches 2 



twelfths long, at the upper part 4 



twelfths in breadth, gradually con- 

 tracting to 1^ twelfth. The rings, 



about 110, are feeble and unossi- 



fied. The bronchial rings are ^'X^ \^ J 



about 20. The contractor muscle 



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