'Annales des Sc. Nat.' 4th series Bot. Tome 9
cah. 5); but I am convinced that a much larger proportion of flowers in
my garden are cross-fertilised by insects, for protected flowers with
their own pollen placed on the stigma never yielded nearly a full
complement of seed; whilst those left uncovered produced fine capsules,
showing that pollen from other plants must have been brought to them,
probably by moths. Plants growing vigorously and flowering in pots in
the greenhouse, never yielded a single capsule; and this may be
attributed, at least in chief part, to the exclusion of moths.
Six flowers on a plant covered by a net were crossed with pollen from a
distinct plant and produced six capsules, containing by weight 4.44
grains of seed. Six other flowers were fertilised with their own pollen
and produced only three capsules, containing only 1.49 grains weight of
seed. From this it follows that an equal number of crossed and
self-fertilised capsules would have contained seeds by weight as 100 to
67. I should not have thought the proportional contents of so few
capsules worth giving, had not nearly the same result been confirmed by
several subsequent trials.
Seeds of the two lots were placed on sand, and many of the
self-fertilised seeds germinated before the crossed, and were rejected.
Several pairs in an equal state of germination were planted on the
opposite sides of Pots 1 and 2; but only the tallest plant on each side
was measured.
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