| The most ingenious man, if he had not witnessed what takes place, could never have imagined what purpose all these parts
But Dr. Crüger saw crowds of large humble-bees visiting the gigantic flowers of this
→not in order
to suck nectar, but to gnaw off the ridges
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
but
to crawl out through the passage formed by the spout or overflow. Dr. Crüger
a "continual procession" of bees thus crawling out of their involuntary bath. The passage is narrow, and is roofed over by the column, so that a bee, in forcing its way out, first rubs its back against the viscid stigma and then against the viscid glands of the pollen-masses. The pollen-masses are thus glued to the back of
bee which first happens to crawl
the passage of a lately expanded flower, and are thus carried away. Dr. Crüger sent me a flower in spirits of wine, with a bee which he had killed before it had quite crawled out
→OMIT
with a pollen-mass
to its back. When the bee, thus provided, flies to another flower, or to the same flower a second time, and is pushed by its comrades into the bucket and then crawls out by the passage, the pollen-mass necessarily comes first into contact with the viscid stigma, and adheres to it, and the flower is fertilised. Now at last we see the full use of
→every part
of the
→flower,
of the
→water-secreting horns,
of the
→
bucket half full of water, which prevents the bees from flying away, and forces them to crawl out through the spout, and rub against the properly placed viscid pollen-masses and the viscid stigma.
The construction of the flower
another closely allied orchid, namely
is widely different, though serving the same end; and is equally curious. Bees visit
→like those
of the Coryanthes, in order to gnaw the labellum; in doing this they inevitably touch a long, tapering, sensitive projection, or, as I have called it,
a
→sensation or vibration to a certain membrane which is instantly ruptured;
this sets free a spring by which the pollen-mass is shot forth, like an arrow, in the right direction, and adheres by its viscid extremity to the back of the bee. The pollen-mass
→of the male plant (for the sexes are separate in this orchid) is
thus carried to
→of the female plant, where
it is brought into contact with the stigma, which is viscid enough to break certain elastic threads, and
→retaining the pollen, fertilisation is effected.
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