Mr. Yarrell on a weffi* Species of Wild Swan. 451 



probably owing to their mates having been killed on their pas- 

 sage north." 



" The windpipes of both these species are found to be exactly 

 alike, though their note is quite different. In serene evenings, 

 after sun-set, I have heard them make a noise not very unlike 

 that of a French-horn, but entirely divested of every note that 

 constituted melody. The voice of the larger is much harsher 

 and louder than that of the smaller." 



If we consider these Swans to be identical with our birds, of 

 which there can be but little doubt, it is difficult to account for 

 the statement here made, that the windpipes of the two species 

 were found to be exactly alike ; except by supposing, either, that 

 the object of the Indians in obtaining these Swans being a 

 lucrative traffic in the feathers and skins, only external exami- 

 nation of the denuded bodies of the birds took place, when the 

 tracheae of both would be seen to enter the hollow keel in the 

 same manner ; or, as the birds of the new species attain their 

 white plumage before the trachea assumes the horizontal direc- 

 tion and insertion, and as old birds are known to be most diffi- 

 cult of approach by the hunter, such Swans only of the rarer 

 sort were examined, as exhibited when the breast-bone was cut 

 into, merely the vertical insertion of the trachea common to the 

 Hooper. 



The difference in the voices of the two species will be ac- 

 counted for on the principles assumed in the description of the 

 organs of voice in birds. The large and irregular calibre of the 

 tube in the Hooper produces the loud and harsh sound; the 

 superior quality of tone, and increased power of modulation in 

 the new species, are owing to the smaller and more uniform 

 tube, and greater flexibility of the bronchiae. The new bird 

 appears to frequent all the localities common to the Hooper. 



From an article on the Hooper in the Supplement to the 



Ornithological 



