Family Anatide
DUCKS, GEESE, AND SWANS.
The two hundred species included in this family are placed in the five subfamilies, Mergine or Mergansers, Anatinæ or River Ducks, Fuligulinæ or Sea Ducks, Anserinæ or Geese, and Cygninæ or Swans. The characters given in the Key to Families should enable one to easily refer a specimen to its proper group. These subfamilies are so well defined that it seems advisable to treat of each one separately. MERGANSERS.
Aside from the general remarks at the head of each subfamily I can add little which will aid in the identification of the species in the field. Ducks are shy creatures, and familiarity with their habits is gained only by long experience.