The flowers of I. balsamina are visited by
humble-bees (8/15. H. Muller 'Die Befruchtung' etc. page 170.), and I am almost
sure that this is the case with the perfect flowers of I. noli-me-tangere. From
the perfect flowers of this latter species covered with a net eleven
spontaneously self-fertilised capsules were produced, and these yielded on an
average 3.45 seeds. Some perfect flowers with their anthers still containing an
abundance of pollen were fertilised with pollen from a distinct plant; and the
three capsules thus produced contained, to my surprise, only 2, 2, and 1 seed.
As I. balsamina is proterandrous, so probably is the present species; and if so,
cross-fertilisation was effected by me at too early a period, and this may
account for the capsules yielding so few seeds.
Drosera rotundifolia.
The first flower-stems which were thrown up by some plants in my greenhouse bore
only cleistogamic flowers. The petals of small size remained permanently closed
over the reproductive organs, but their white tips could just be seen between
the almost completely closed sepals. The pollen, which was scanty in amount, but
not so scanty as in Viola or Oxalis, remained enclosed within the anthers,
whence the tubes proceeded and penetrated the stigma. As the ovarium swelled the
little withered corolla was carried upwards in the form of a cap.
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