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CHAPTER XIV. 
swans': — THE COMMON, THE WHOOPING, THE CHANGELESS, 
AND Bewick's swans. 
THE Cygnince is the second family of the Sifters, and con- 
sists of a small group of very large birds called Swans, 
which differ little in their general habits from the Anserinoe 
(Geese) and the Anatince (Ducks). They are of larger size, 
have comparatively short legs, and elongated necks, and 
large and peculiarly shaped bills, of which the breadth is 
nearly uniform. The Swans are gregarious, migratory, flying 
in lines when journeying ; have a strong and rapid flight; 
never dive when searching for food, which consists of vege- 
table substances ; w^alk slowly and ungracefully, but swim 
with great ease and dignity. The birds constituting the genus 
Cygnus^ inhabit chiefly the cold and temperate regions 
of the globe. Eight species only are known, of which 
some have a bare fleshy knob at the base of the upper 
mandible, above which in others that part is flat or concave. 
There is also a diflerence in the construction of the wind- 
pipe, which is only obvious to the scientific naturalist. 
The Common Tame Swan {Cygnus Olor), sometimes 
called the Mute Swan. 
The Whooping Swan (C. miisicus), sometimes called 
the Wild, or Whistling Swan ; the Elk, or the Hooper. 
The Changeless Swan (C. mmiitabiHs), sometimes 
called the Polish Swan. 
Bewick's, and The American Swans {C. BewicJciu and 
C, Americanus), — Yarrell admits the first of the above into 
his list of British Swans, but Macgillivray excludes it, deny- 
ing that there is any evidence of its ever having been 
