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Buds, Blossoms, Fruits
Comments by Readers
Natural Devices for Cross-Fertilization.* — In the
December number (page 772) you quote an article from
Popular Science News, under the above heading. Text
and illustrations refer to the stamens, the withered
stigmas, etc., etc., explaining the devices to secure a
cross. The best point escapes notice. 

* Am. Jour. Science, p. 308, 1876, "Sensitive Stigmas as an aid to
cross-fertilization of flowers," by Prof. W. J. BEAL.

109
At the annual meeting of the American Association for the Advancement
of Science, held in Detroit in 1876, I showed that
the two broad, flat stigmas of trumpet creeper, martynia,
bladderwart, and several species of mimulus, were
curved apart in fresh flowers. Ona warm day, as an insect
crowds into the flower the stigmas are touched before
the anthers are reached. After a few seconds,
while the insects "sips the water" below, the two
stigmas approach each other, and mutually and completely
cover the portion which is sensitive to pollen.
As the insect backs out of the flower, no pollen can be
left on the stigma of the same flower. I then anticipated,
and have since seen, that the same state of things
exist, in pinquicula, and in species of catalpa or bignonia.
—W. J. BEAL.