Watertown republican. [volume] (Watertown, Wis.) 1860-1906, 1875-03-17
The Relations Between Flowers and
Insects

The Relations Between Flowers and
Insects.
The fertilization of flowers by in
sects is, in more senses than one, a
fruitful subject, and nowhere has it
been better treated than by Sir John
lubbock, in very recent paper devot-
ed to the relations existing between
the common wild flowers and the in
sect world, It appears that even in the
last century it was shown by the Ger
man botanlst, Sprengel, that the gen
eral structure, the shape, the color and
the honey of flowers have reference to
the visits of insects, which perform
the important work of transferring
the pollen, or .fructifying medium,
from the stamens to the pistil. But
Mr.. Darwln's researches were the first
to attract any general attention.
Everyone who has watched a hive of
bees, knows how important flowers
are to insects, but it is only lately that
we have learned how important insects
are to flowers. It seems to be certain
that flowers have their bright colors for
the purpose of attracting insects, and
it is noteworthy that most night
flowers are white, that they NAV be seen,
while their near cogeners are colored.
Whether one believes in MIR. Darwin's
theory of selection or not, it is obvious
that those flowers which, either by their
larger size, their brighter hue, their
sweeter scent or their more abundant
honey, are most enticing to isects, will
have a marked advantage in their
struggle for existence, and be most
likely to perpetuate their race. The in
sects transfer the impregnating pollen
pistn of the same flower, and some
times from the stamens of one flower
to the pistil of another. The value of
the latter, or cross sterilization, has been
fully proved by experiment. Breeders
know how necessary it is, in the case
of sheep Or cattle, to avoid the Gin and
in system of breeding, and it is no
less essential in the case of plants In
regard to some flowers, like the aris-
tolchia and the arum, small fly enters
the tube In search of honey; once in he
finds that owing to the fringe of hairs,
turned backward, with which the tube
is provided, he cannot get out again;
thus he is imprisoned until the pistil
passes maturity, when the stamens
ripen and shed their pollen, with which
the fly becomes thoroughly busted, and
he Is allowed to escape with his drop of
honey which has meanwhile been
secreted. Many flowers have ingenious
devices resembling levers, by means of
which bee is showered with the pollen
whenever he pays his visits. In the
case Of some of the orchids the flower
is SO sensitive to the approach of all
insect that it actually throws the pollen
at him without his coming in contact
with it. Every one has observed that
even in fine weather certain flowers close
at particular hours. This floral habit
of going to sleep is very curious. The
English daisy, for instance, opens at
sunrise and closes at sunset, whence its
name "day's eye." The dandelion
opens at and closes at 5; the arenaria
libra is open from to 3; the mouse
ear hawkweed wakes at and goes to
sleep at 3; while tragopogon pratensis
opens at in the morning and is closed
just before II, whence it's English name,
John go to bed at noon,' and it is SO
exact that farmers boys in England
regulate their dinner hour by it. Other
plants, on the contrary open in the
evening. Why should flowers thus go
to sleep? Why should there be this
difference in the times Of wakefulness
Simply to accommodate themselves to
the habits of the insects which assist in
their fertilization. Those fertilized by
night-fying insects would derive no ad-
vantage from being open by day; and
those which are fertilized by bees would
gain nothing by remaining open at
| night It would in fact be distinct
disadvantage, because they might be
robbed of their honey and pollen by IL
sects VINO, from their structure, are not
capable of fertilizing them.