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Darwin, Charles, 1809-1882

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

58 seeds. Therefore the fertility of the six legitimate to that of the twelve
illegitimate unions, as judged by the proportion of flowers which yielded
capsules, is as 100 to 15, and judged by the average number of seeds per capsule
as 100 to 49. This plant, in comparison with the two South American species
previously described, produces many more seeds, and the illegitimately
fertilised flowers are not quite so sterile.
Oxalis rosea.
Hildebrand possessed in a living state only the long-styled form of this
trimorphic Chilian species. (4/14. 'Monatsber. der Akad. der Wiss. Berlin' 1866
page 372.) The pollen-grains from the two sets of anthers differ in diameter as
9 to 7.5, or as 100 to 83. He has further shown that there is an analogous
difference between the grains from the two sets of anthers of the same flower in
five other species of Oxalis, besides those already described. The present
species differs remarkably from the long-styled form of the three species
previously experimented on, in a much larger proportion of the flowers setting
capsules when fertilised with their own-form pollen. Hildebrand fertilised 60
flowers with pollen from the mid-length stamens (of either the same or another
flower), and they yielded no less than 55 capsules, or 92 per cent. These
capsules contained on an average 5.


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