RED-HEADED DUCK. 31 1 



The trachea, when moderately extended, measures 10 inches in length, 

 and is furnished with strong lateral or contractor muscles, a pair of endo- 

 tracheal, and a pair of more slender sterno-tracheal. Its diameter at the 

 upper part is 4|- twelfths, it gradually contracts to 3^ twelfths, enlarges to 

 4^- twelfths, and at the distance of 7i inches from the upper extremity, 

 forms a dilatation about an inch in length, and T 7 2 in its greatest diameter, 

 but composed of distinct rings, then contracts to ~^, and ends in a bony and 

 membranous expansion, forming on the left side an irregular thin disk, con- 

 vex towards the right, and flattened towards the left, where it is membra- 

 nous. The expansions of the trachea are thus similar to those of the Red- 

 breasted Merganser, but of less extent; the rings are of equal breadth on 

 both sides, but alternately overlap each other, one side being partially con- 

 cealed by the corresponding sides of those above and below it, while the 

 other stands exposed. The lower larynx is formed of ten united rings, to- 

 gether with the bony and membranous expansion described. The tracheal 

 rings, rather broad and osseous, are 118; the half-rings of the bronchi about 

 16. 



RED-HEADED DUCK. 



■f-FuxiGULA Ferina, Linn. 



PLATE CCCXCVL— Male and Female. 



At New Orleans, this bird is commonly known by the name of "Dos 

 Oris." It arrives there in great flocks, about the first of November, and 

 departs late in April, or in the beginning of May. On the lakes Borgne, 

 St. John, and Ponchartrain, it is very abundant, keeping in large flocks, 

 separate from the other species. In that part of the country its food con- 

 sists of small fishes, in pursuit of which it is seen constantly diving. It is 

 caught in different sorts of nets, and easily kept in confinement, feeding 

 greedily on Indian corn, whether entire or crushed by the millstone. In 

 1816, many thousands of these Ducks as well as others of different species, 

 were caught in nets by a Frenchman, who usually sent them alive to market 

 in cages from the narrows of the Lakes, especially from those called "La 



