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To insure
cross-fertilization, some of the bladder-campion flowers have
stamens only, some have a pistil only; some have both organs
maturing at different times. In all the night-flowering Silene,
each flower, unless unusually disturbed, lasts three days and
three nights. Late in the afternoon of the first day, when the
petals begin to expand, the five stamens opposite the sepals
lengthen in about two hours, and by sunset the anthers, which
have matured at the same time, are covered with pollen. So they
remain until the forenoon of the second day, and then the emptied
anthers hang like shriveled bags, or drop off altogether. Late in
the second afternoon, the second set of stamens repeat the
actions of their predecessors, bend backward and shed their
anthers the following, that is to say the third, morning. But on
the third afternoon up rise the S-shaped, twisted stigmas, which
until now had been hidden in the center of the flower. Moths,
therefore, must transfer pollen from younger to older blossoms.


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