One alighting on the lower lip must thrust his tongue
beneath the upper one to reach the nectar in the spur, passing on
its way the irritable stigma, which receives any pollen he has
brought in. Instantly it is touched, the stigma folds up to be
out of the way of the tongue when it is withdrawn from the spur
now laden with fresh pollen. It is thus that self-fertilization
is escaped. Many vigorous seeds follow in each capsule. This
marvelous piece of mechanism is what Thoreau termed "a
dirty-conditioned flower, like a sluttish woman with a gaudy
yellow bonnet"!
Not through its seeds alone, however, has the little plant
succeeded in firmly establishing itself. In early autumn the
stems terminate in large buds which, falling off, lie dormant all
winter at the bottom of the pond. In spring they root and put
forth leaves bearing bladders, which at this stage of existence
are filled with water to help anchor the plant. As flowering
season approaches, the bladders undergo an internal change to fit
them for a change of function; they now fill with air, when the
buoyed plant rises toward the surface to send up its flowering
scape, while the bladders proceed with their nefarious practices
to nourish it more abundantly while its system is heavily taxed.
Pages:
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789