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Darwin, Charles, 1809-1882

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

The short-styled form, which grows in the
Gardens at Kew, has never there produced fruit.
Forsythia viridissima appears likewise to be heterostyled; for Professor Asa
Gray says that although the long-styled form alone grows in the gardens at
Cambridge, U.S., the published figures of this species belong to the short-
styled form.
Cordia [sp.?] (Cordiaceae).
Fritz Muller sent me dried specimens of this shrub, which he believes to be
heterostyled; and I have not much doubt that this is the case, though the usual
characteristic differences are not well pronounced in the two forms. Linum
grandiflorum shows us that a plant may be heterostyled in function in the
highest degree, and yet the two forms may have stamens of equal length, and
pollen-grains of equal size. In the present species of Cordia, the stamens of
both forms are of nearly equal length, those of the short-styled being rather
the longest; and the anthers of both are seated in the mouth of the corolla. Nor
could I detect any difference in the size of the pollen-grains, when dry or
after being soaked in water. The stigmas of the long-styled form stand clear
above the anthers, and the whole pistil is longer than that of the short-styled,
in about the ratio of 3 to 2.
The stigmas of the short-styled form are seated beneath the anthers, and they
are considerably shorter than those of the long-styled form.


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