222 THE N&STS AND EGGS OF BRITISH BIRDS. 



DIAGNOSTIC CHARACTERS : The large size and chalky 

 coating readily distinguish the egg of the Gannet from 

 those of all other species breeding in our islands with 

 which it is at all likely to be confused. 



Family ANATID^E. Genus CYGNUS. 



Sub-family CYGNIN&. 



MUTE SWAN. 



CYGNUS OLOR (Gmeliri). 

 Single Brooded. Laying season, March, April, and May. 



BRITISH BREEDING AREA : There can be little doubt 

 that the Mute Swan has never bred in our islands in a 

 perfectly wild state. In a more or less domesticated 

 condition, however, it breeds wherever man affords it 

 his protection, consequently its distribution is a purely 

 artificial one, and possesses no ornithological interest or 

 value whatever. 



BREEDING HABITS : The Mute Swan is of course a 

 resident in our islands, but it is not improbable that 

 occasionally a few really wild birds pay them a visit 

 from the Continent during winter. In some cases this 

 Swan is to a certain extent gregarious during the 

 breeding season, numbers of birds nesting in somewhat 

 close companionship, but I should say that generally 

 each pair frequent some chosen spot from which all 

 intruders are jealously driven. The Swan pairs for life, 

 and yearly returns to one place to breed, generally 

 making a new nest annually, but occasionally using the 

 old one. The nest is a huge, conspicuous structure, 

 usually placed on an island, or amongst the rank 



