Vill Introduction. 
Birds 
of this Order are especially fitted for aquatic 
ORDER VI.—WNatatores, or Swimmers. 
life. and comprise the Ducks, Geese, Swans, 
Cormorants, Gulls, Grebes, Loons, and Terns ; 
Petrels, Auks, Sheldrakes, Gannets, Guillemots, 
and Puffins. 
Many species of birds that were quite common 
in Canada at the beginning of this century, are 
now rarely seen, and several have become extinct 
in comparatively recent times. 
