the fruit
falls. When torn from the tree the twist in the bract enables the
wind to keep the cluster rapidly whirling around, and by whirling
it is enabled to remain longer suspended in the air and thus increase
the chances for a long journey. In throwing some of these from a
third-story window, it was found that a bract with no fruit attached
would reach the ground sooner than a bract that bore from two to four
solid nuts. The empty or unloaded bracts tumble and slide through
the air endwise, with nothing to balance them or steady their descent,
while the fruit on other bracts holds them with one side to the air,
which prolongs their descent. The less a loaded bract whirls, the
faster its descent, and the more a bract whirls when the wind blows,
the farther it is carried. The bract that is weighted with a load
of fruit acts as a kite held back by a string, and when in this position
the wind lifts the whole as well as carries it along. Before snow
had fallen in 1896, by repeated moves on a well-mowed lawn, fruit
and bracts were carried about two hundred feet, while with snow on
the ground the distance was almost unlimited, excepting where there
were obstructions, such as bushes and fences. When there is a crust
on the snow and a good wind, the conditions are almost perfect. Over
the snow the wind drives the bracts, which drag along the branch of
fruit much as a sail propels a boat. The curving of the edges of the
bract toward the fruit enables the wind to catch it all the better,
and to lift it more or less from the snow. With changes in the direction
of the wind, there is an opportunity for the fruit of a single tree,
if not too much crowded by others, to spread in all directions. After
watching these maneuvers, no one could doubt the object of the bent
bracts of the basswood, and as these vary much in length and width
and shape on different trees, it would seem that perhaps nature is
still experimenting with a view to finding the most perfect structure
for the purpose.

About one hundred and thirty paces west of the house in which I live
stand two birch trees. One windy winter day I made some fresh tracks
in the snow near my house, and within a few minutes the cavities looked
as though some one had sprinkled wheat bran in them, on account of
the many birch seeds there accumulated.

Other fruits in winter can be experimented with, such as that of box
elder, black ash, birches, tulip tree, buttonwood, ironwood, blue