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Darwin, Charles, 1809-1882

"The Different Forms of Flowers on Plants of the Same Species"

(5/11. For
full details of this experiment, see my 'Effects of Cross and Self-
fertilisation' 1876 page 220.) When these illegitimate plants were transferred
to fairly good soil out of doors, they became during the two following years
much more dwarfed in stature and produced very few flower-stems; and although
they must have been legitimately fertilised by insects, they yielded capsules,
compared with those produced by the surrounding legitimate plants, in the ratio
only of 5 to 100! It is therefore certain that illegitimate fertilisation,
continued during successive generations, affects the powers of growth and
fertility of P. veris to an extraordinary degree; more especially when the
plants are exposed to ordinary conditions of life, instead of being protected in
a greenhouse.
[EQUAL-STYLED RED VARIETY OF Primula veris.
Mr. Scott has described a plant of this kind growing in the Botanic Garden of
Edinburgh. (5/12. 'Proceedings of the Linnean Society' volume 8 1864 page 105.)
He states that it was highly self-fertile, although insects were excluded; and
he explains this fact by showing, first, that the anthers and stigma are in
close apposition, and that the stamens in length, position and size of their
pollen-grains resemble those of the short-styled form, whilst the pistil
resembles that of the long-styled form both in length and in the structure of
the stigma.


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