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Darwin, Charles, 1809-1882

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

It is
of importance to observe this, as it shows that the same general result was
obtained during two successive years; but more especially because 1863 was a
very hot and dry season, and the plants had occasionally to be watered. This did
not prevent the full complement of seed being produced from the more fertile
unions; but it rendered the less fertile ones even more sterile than they
otherwise would have been. I have seen striking instances of this fact in making
illegitimate and legitimate unions with Primula; and it is well known that the
conditions of life must be highly favourable to give any chance of success in
producing hybrids between species which are crossed with difficulty.
TABLE 4.23. Lythrum salicaria, long-styled form.
TABLE 4.23.1. Legitimate union.
13 flowers fertilised by the longest stamens of the mid-styled. These stamens
equal in length the pistil of the long-styled.
Product of good seed in each capsule.
36 53
81 0
0 0
0 0
0 0
- 0
45
41
38 percent of these flowers yielded capsules. Each capsule contained, on an
average, 51.2 seeds.
TABLE 4.23.2. Legitimate union.
13 flowers fertilised by the longest stamens of the short-styled. These stamens
equal in length the pistil of the long-styled.
Product of good seed in each capsule.


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