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Darwin, Charles, 1809-1882

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

There is also a
difference in shape, the grains from the short-styled plants being nearly
spherical, those from the long-styled being oblong with the angles rounded; this
difference disappears when the grains are distended with water. The long-styled
plants generally tend to flower a little before the short-styled: for instance,
I had twelve plants of each form growing in separate pots and treated in every
respect alike; and at the time when only a single short-styled plant was in
flower, seven of the long-styled had expanded their flowers.
We shall, also, presently see that the short-styled plants produce more seed
than the long-styled. It is remarkable, according to Professor Oliver, that the
ovules in the unexpanded and unimpregnated flowers of the latter are
considerably larger than those of the short-styled flowers (1/3. 'Natural
History Review' July 1862 page 237.); and this I suppose is connected with the
long-styled flowers producing fewer seeds, so that the ovules have more space
and nourishment for rapid development.
To sum up the differences:--The long-styled plants have a much longer pistil,
with a globular and much rougher stigma, standing high above the anthers. The
stamens are short; the grains of pollen smaller and oblong in shape. The upper
half of the tube of the corolla is more expanded.


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