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not been observed. ‘The Hooper feeds on aquatic 
plants and insects, in the search of which it can 
keep its head under water for some time, but it 
never dives. Its nest, which is a large structure, 
is formed on the ground with flags, rushes, leaves, 
and marshy plants. The female lays six or seven 
egos, tinged with yellowish green. 
SWAN, MUTE. 
TAME Swan. 
Cyrenus oLor, Zemm. 
Our “ Mute” half-domesticated Swan is too well 
known to require description; the large tubercle 
or knob at the base of its bill at once distinguish- 
ing this graceful species from its congeners. ‘These 
birds are far less numerous in the Thames than 
they used to be. The greatest number at present 
on that river belong to the Queen, and the Com- 
panies of Vintners and Dyers own the next largest 
proportion. The swan marks are made upon the 
upper mandible with a knife or other sharp instru- 
ment. This elegant bird is said to exist in a wild 
state in Russia and Siberia. 
