INTRODUCTION, 15 
Goose, are Land Birds—at least during their breeding-season, 
and they breed on the ground. 
The Ducks—for which the Wild Duck or Mallard (Anas 
boscas) may be taken as a type—are all so much alike, that the 
genera into which their numerous species have been grouped 
present no characters which make it needful for us to deal with 
them here. They form another cosmopolitan group of broad- 
billed web-footed Birds. 

Fig. 12. 

The Black-necked Swan (Cygnus nigricollis). 
The Harlequin Duck, which rarely visits us from the North, 
is a handsome Bird. But there are many yet handsomer, and 
the brilliant and artificially-marked Mandarin Duck is especially 
noticeable. 
Of Swans there are only some eleven species, whereof 
that “ Rara avis” of our Latin grammars, the Black Swan, is 
Australian, while the White Swan with a black neck, from 
South America, is a remarkably handsome species. 
The Mergansers constitute a very small group of Water 
Birds, markedly different from the before noted web-footed ones, 
