v.) also entertains
her guests in. Fine hairs within secrete tiny drops of fluid at
their tips - a secretion which hardens into a brittle crust, like
a syrup's, when it dries. Darwin became especially interested in
this flower through a delightful correspondence with Professor
Asa Gray, who was the first to understand it, and he finally
secured a specimen to experiment on.
"I first introduced some flies into the labellum through the
large upper opening," Darwin wrote, "but they were either too
large or too stupid, and did not crawl out properly. I then
caught and placed within the labellum a very small bee which
seemed of about the right size, namely Andrena parvula.... The
bee vainly endeavored to crawl out again the same way it entered,
but always fell backwards, owing to the margins being inflected.
The labellum thus acts like one of those conical traps with the
edges turned inwards, which are sold to catch beetles and
cockroaches in London kitchens. It could not creep out through
the slit between the folded edges of the basal part of the
labellum, as the elongated, triangular, rudimentary stamen here
closes the passage.
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