which are light and incoherent, being blown by the wind through mere chance
on to the stigma; and this is the simplest plan which can well be
conceived. An almost equally simple, though very different plan occurs in
many plants in which a symmetrical flower secretes a few drops of nectar,
and is consequently visited by insects; and these carry the pollen from the
anthers to the stigma.

>From this simple stage we may pass through an inexhaustible number of
contrivances, all for the same purpose and effected in essentially the same
manner, but entailing changes in every part of the flower. The nectar may
be stored in variously shaped receptacles, with the stamens and pistils
modified in many ways, sometimes forming trap-like contrivances, and
sometimes capable of neatly adapted movements through irritability or
elasticity. From such structures we may advance till we come to such a
case of extraordinary adaptation as that lately described by Dr. Cruger in
the Coryanthes. This orchid has part of its labellum or lower lip hollowed
out into a great bucket, into which drops of almost pure water continually
fall from two secreting horns which stand above it; and when the bucket is
half-full, the water overflows by a spout on one side. The basal part of
the labellum stands over the bucket, and is itself hollowed out into a sort
of chamber with two lateral entrances; within this chamber there are
curious fleshy ridges. The most ingenious man, if he had not witnessed
what takes place, could never have imagined what purpose all these parts
serve. But Dr. Cruger saw crowds of large humble-bees visiting the
gigantic flowers of this orchid, not in order to suck nectar, but to gnaw
off the ridges within the chamber above the bucket; in doing this they
frequently pushed each other into the bucket, and their wings being thus
wetted they could not fly away, but were compelled to crawl out through the
passage formed by the spout or overflow. Dr. Cruger saw a "continual
procession" of bees thus crawling out of their involuntary bath. The