88 
HISTORY OF 
horizontal with the part going towards the bronchiae, or lower 
extremity. 
The following Cut represents the sternum and trachea of 
C. Bewickii, a portion of the bone on the inside being removed 
to shew the convolution of the tube : — 
In the Hooper, at the same point, the part of the tube of the 
trachea going towards the mouth, is placed vertically over that 
going towards the bronchiae. — See the following Cut : — 
Another species of Swan has lately been described by Mr. 
Yarrell, (Cygnus Buccinator of the “ Fauna Boreali Ameri- 
cana,”) of which, as we think it not improbable it may occur 
in the British Isles, being an American species, we shall give a 
short description. It has the bill entirely black ; and the 
trachea, after penetrating the keel, recurves, having a horizontal 
