2 Mr. Yarrell's Description of the Organ of Voice 



internal, in Cygnus Buccinator, will be found to be all equally distinct from 

 both. 



Cygnus Buccinator is the most common swan in the interior of the fur- 

 countries of North America ; and it is to this species, which is called the 

 Trumpeter, that the largest portion of the swan-skins imported by the Hud- 

 son's Bay Company belong. 



These swans probably require five or six years to arrive at their full 

 size; but this point attained, they are considerably larger than the oldest 

 Hooper. 



The beak of the Trumpeter is entirely black, without any of the yellow- 

 orange colour so conspicuous in the Hooper and Bewick's swan ; and, being 

 at the same time larger, longer, and more depressed, at once distinguishes 

 this new species. 



The forehead alone is tinged with rust-colour, and this tint prevails over a 

 larger space in younger specimens ; the rest of the plumage is pure white : the 

 third quill-feather of the wing is the longest ; the tail-feathers 24 in number ; 

 the legs black. 



The trachea is made up of narrow bony rings and small intervening mem- 

 branous spaces as far as the first convolution within the breast-bone, but the 

 returning portion of the tube, forming a second convolution, is composed of 

 broader and stronger bony rings with wider intervals. In these peculiarities 

 of structure it resembles the trachea of the Hooper ; but in its course within 

 the sternum, as also in the form of the bronchise, it is decidedly diff'erent. 



The trachea, after descending by the neck, passes backwards within the 

 keel and between the two plates of the breast-bone to the depth of six inches, 

 then curving horizontally and slightly inclining upwards, returns, at first by 

 the side of, and afterwards over, the first inserted portion, near two thirds of 

 the whole distance. A second curve of this returning portion is then suddenly 

 elevated two inches above the line of the superior surface of the keel, and 

 traverses the interior of a hollow circular protuberance on the dorsal surface 

 of the sternum itself. The usual ascending curve of the trachea then ensues, 

 by which the tube, ultimately receding, gains the internal cavity of the breast. 

 The bone of divarication is placed over the centre of the protuberance before 

 mentioned. The bronchise are but two inches each in length, small at their 



