The Descent of Man

chives Neerlandaises,' tom. vi. 1871.—On Ardea,
Audubon, ibid. vol. iii. p. 139.) But it is
doubtful whether the continued development
of such feathers is the result of the selection of
successive beneficial variations (though this is
the most probable view with birds of paradise)
or merely of continuous growth. Most fishes
continue increasing in size, as long as they are
in good health and have plenty of food; and a
somewhat similar law may prevail with the
plumes of birds.
CLASS V.
WHEN THE ADULTS OF BOTH SEXES
HAVE A DISTINCT WINTER AND SUMMER
PLUMAGE, WHETHER OR NOT THE MALE
DIFFERS FROM THE FEMALE, THE YOUNG
RESEMBLE THE ADULTS OF BOTH SEXES
IN THEIR WINTER DRESS, OR MUCH MO-
RE RARELY IN THEIR SUMMER DRESS, OR
THEY RESEMBLE THE FEMALES ALONE. OR