HOOPER. 



191 



Caspian Sea in winter. M. Menetries says that it is seen 

 at Bakou in January and February. 



The Hooper may be immediately distinguished from 

 other species among the Swans, by the characters to be 

 observed about the head. Willughby, besides giving a 

 figure of the whole bird, introduced in addition the head 

 only, of larger size, to show the specific peculiarity. 

 Edwards gave the head of our Mute Swan on the same 

 plate with his figure of the Hooper, to show the distinc- 

 tion. This plan of engraving the heads only has been 

 adopted with excellent effect by Col. Hawker, in his 

 very popular work, and I have profited by his example of 

 giving the head only, of large size, rather than give repeti- 

 tions of similar white bodies. The first here introduced is 

 the head of the adult Hooper. The anterior part of the 

 beak is depressed and black ; the posterior or basal part 



