He who will compare the structure of the whole flower in both forms of L.
perenne and grandiflorum, and, as I may add, of L. flavum, will not doubt about
the meaning of this torsion of the styles in the one form alone of L. perenne,
as well as the meaning of the divergence of the stigmas in the short-styled form
of all three species. It is absolutely necessary as we know, that insects should
carry pollen from the flowers of the one form reciprocally to those of the
other. Insects are attracted by five drops of nectar, secreted exteriorly at the
base of the stamens, so that to reach these drops they must insert their
proboscides outside the ring of broad filaments, between them and the petals. In
the short-styled form of the above three species, the stigmas face the axis of
the flower; and had the styles retained their original upright and central
position, not only would the stigmas have presented their backs to the insects
which sucked the flowers, but their front and fertile surfaces would have been
separated from the entering insects by the ring of broad filaments, and would
never have received any pollen. As it is, the styles diverge and pass out
between the filaments. After this movement the short stigmas lie within the tube
of the corolla; and their papillous surfaces being now turned upwards are
necessarily brushed by every entering insect, and thus receive the required
pollen.
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