Therefore
the average height of the fifteen crossed plants in all three pots was
38.06 inches, and that of the fifteen self-fertilised plants 26.13
inches; or as 100 to 69.
28. CHENOPODIACEAE.--Beta vulgaris.
A single plant, no others growing in the same garden, was left to
fertilise itself, and the self-fertilised seeds were collected. Seeds
were also collected from a plant growing in the midst of a large bed in
another garden; and as the incoherent pollen is abundant, the seeds of
this plant will almost certainly have been the product of a crossed
between distinct plants by means of the wind. Some of the two lots of
seeds were sown on the opposite sides of two very large pots; and the
young seedlings were thinned, so that an equal but considerable number
was left on the two sides. These plants were thus subjected to very
severe competition, as well as to poor conditions. The remaining seeds
were sown out of doors in good soil in two long and not closely
adjoining rows, so that these seedlings were placed under favourable
conditions, and were not subjected to any mutual competition. The
self-fertilised seeds in the open ground came up very badly; and on
removing the soil in two or three places, it was found that many had
sprouted under ground and had then died. No such case had been observed
before. Owing to the large number of seedlings which thus perished, the
surviving self-fertilised plants grew thinly in the row, and thus had an
advantage over the crossed plants, which grew very thickly in the other
row.
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