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Darwin, Charles, 1809-1882

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

(4/2. 'Die Befruchtung der Blumen' 1873 page 193.) The numbers
refer to divisions of the micrometer equalling 1/300 millimetres. The grains,
distended with water, from the mid-length stamens are 7 to 7 1/2, and those from
the shortest stamens 6 to 6 1/2 in diameter, or as 100 to 86. The capsules of
this form contain on an average 93 seeds: how this average was obtained will
presently be explained. As these seeds, when cleaned, seemed larger than those
from the mid-styled or short-styled forms, 100 of them were placed in a good
balance, and by the double method of weighing were found to equal 121 seeds of
the mid-styled or 142 of the short-styled; so that five long-styled seeds very
nearly equal six mid-styled or seven short-styled seeds.
MID-STYLED FORM.
The pistil occupies the position represented in Figure 4.10, with its extremity
considerably upturned, but to a variable degree; the stigma is seated between
the anthers of the longest and the shortest stamens. The six longest stamens
correspond in length with the pistil of the long-styled form; their filaments
are coloured bright pink; the anthers are dark-coloured, but from containing
bright-green pollen and from their early dehiscence they appear emerald-green.
Hence in general appearance these stamens are remarkably dissimilar from the
mid-length stamens of the long-styled form.


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