324 



ANSERES. 



ANATIDJl. 



ANATIDjE 



Cygnus olor (Gmelin*). 



THE MUTE SWAN. 



Cygnus olor. 



The most obvious difference, and that wbicli will imme- 

 diately strike the observer on comparing the representation 

 of our Mute, half-domesticated Swan, with those of the 

 Whooper and Bewick's Swans, is, that the two most con- 

 spicuous colours on the beak occupy opposite situations in 

 these species. In the Whooper and Bewick's Swans the 

 anterior portion of the beak is black, the base and the lore 

 to the eye, orange-yellow ; but in the Mute Swan it is the 

 anterior portion of the beak which is of a rich reddish- 

 orange, the base and the lore to the eye black, and on the 

 upper part of the forehead there is a prominent black 

 tubercle or knob, which in old males attains considerable 

 size. 



* Anas Olor, Gmelin, Syst. Nat. i. p. 501 (1788). 



