Mr. YARRELL on a new 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 
trachez 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 bronchie. 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 
