tongue. Each pollinium consists of two leaves of pollen united
for about half their length in the middle with elastic threads.
As the pollinia are attached parallel to the disk, they stick
parallel on the bee's tongue, yet she may fold up her proboscis
under her head, if she choose, without inconvenience from the
pollen masses, or without danger of loosening them. Now, having
finished sucking the newly opened flowers at the top of the
spike, away she flies to an older flower at the bottom of another
one. Here a marvelous thing has happened. The passage which, when
the flower first expanded, scarcely permitted a bristle to pass,
has now widened through the automatic downward movement of the
column in order to expose the stigmatic surfaces to contact with
the pollen masses brought by the bee. Without the bee's help this
orchid, with a host of other flowers, must disappear from the
face of the earth. So very many species which have lost the power
to fertilize themselves now depend absolutely on these little
pollen carriers, it is safe to say that, should the bees perish,
one half our flora would be exterminated with them. On the slight
downward movement of the column in the ladies' tresses, then, as
well as on the bee's ministrations, the fertilization of the
flower absolutely depends. "If the stigma of the lowest flower
has already been fully fertilized," says Darwin, "little or no
pollen will be left on its dried surface; but on the next
succeeding flower, of which the stigma is adhesive, large sheets
of pollen will be left. Then as soon as the bee arrives near the
summit of the spike she will withdraw fresh pollinia, will fly to
the lower flowers on another plant, and fertilize them; and thus,
as she goes her rounds and adds to her store of honey, she
continually fertilizes fresh flowers and perpetuates the race of
autumnal spiranthes, which will yield honey to future generations