ORDER V. DUCKS, GEESE, AND SWANS. 
ANSERES. 
Family 1. DUCKS, GEESE, and SWANS. Awnatipa#. 49 
species, 6 subspecies. 
The Anatidze of North America are placed in five well-marked sub- 
families, the Mergansers (J/ervging), River Ducks (Anating), Sea Ducks 
(Fuliguline), Geese (Ansering), and Swans (Cyenine). 
The Mergansers, Saw-bills, or Shelldrakes are fish-eating Ducks and 
their rounded bills, set with toothlike projections along the sides, are 
of evident use to them in holding their prey. 
The River Ducks include such well-known species as the: Mallard, 
Black Duck, and Widgeon. They differ from the Bay or Sea Ducks 
in not having a well-developed web or flap on the hind-toe. Asa 
rule they feed in shallow water by tipping, standing on their heads, as 
it were, while reaching the bottom for food. 
The Bay or Sea Ducks have the hind-toe webbed. They feed, as a 
rule, in deeper water than the River Ducks, sometimes descending to 
the bottom in water over one hundred feet deep. During the winter 
they gather in flocks often of several thousand individuals, and fre- 
quent the larger bodies of water. 
With both the River and Bay Ducks the sides of the broad, flat bill 
are set with gutters which serve as strainers, retaining the mollusks, 
seeds and roots of aquatic plants on which these Ducks feed, while the 
mud or water taken in with the food is forced out the sides of the bill 
as it closes. 
Geese are more terrestrial than Ducks and often visit the land to nip 
the grass. This is particularly true in the west where large flocks of 
Geese, especially Snow Geese, may be seen feeding on the prairies. 
On the water they feed over shallows by tipping and probing the 
bottoms. 
Swans also feed from the surface of the water either by simply im- 
mersing the head and neck or by half submerging the body, when, with 
the tail pointed to the zenith, the length of their reach is greatly in- 
creased. 
In spite of their comparatively short wings the large muscles attach- 
ed to them give to the Anatide great power of flight. Not only do 
they make extended journeys, when migrating, without a rest, but they 
attain a speed which is surpassed by but few birds. Some of the 
smaller species, when alarmed, doubtless flying at the rate of one 
hundred miles an hour. 
In common with other diving water birds the Ducks, when molting, 
lose most of their wing feathers all at once, and for a time are there- 
fore unable to fly. During this comparatively helpless period the 
brightly colored males assume in part the plumage of the females and 
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