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Above the lower tree-line, which is also the snowline, mapped out abruptly by the sun, one finds spreading growth of pinon, juniper, branched nearly to the ground, lilac and sage, and scattering white pines. There is no special preponderance of self-fertilized or wind-fertilized plants, but everywhere the demand for and evidence of insect life.
The giants were called "dominant"; the disappearing dwarfs, "recessive". But among the second generation of this giant offspring, giants and dwarfs appeared in the proportion of 3 to 1. But when these dwarfs were self-fertilized, successive generations were all dwarfs. The recessive character was not lost, but appeared again.
They come from seed, when this is taken from striped individuals, and thence revert from time to time to the corresponding monochromatic type. But whether they would do so when self-fertilized, and whether the reversionary individuals are always bound to return towards the center of the group or towards the opposite limit, remains to be investigated.
The seedlings of this flower, coming now into competition with the existing weaker self-fertilized forms, by the increased vigor won in the struggle of their immediate surroundings, and inheriting the peculiarity of their parent, showed flowers possessing the same cross-fertilizing device.
Above the lower tree-line, which is also the snow-line, mapped out abruptly by the sun, one finds spreading growth of piñon, juniper, branched nearly to the ground, lilac and sage, and scattering white pines. There is no special preponderance of self-fertilized or wind-fertilized plants, but everywhere the demand for and evidence of insect life.
The differences between the specimens grown from a single lot of seeds, for instance from the seeds of one self-fertilized capsule are, as I have said, partly due to the divergences which are always present in a bed, even if the utmost care has been taken to make it as uniform as possible.
This miscarriage does not affect all the grains in the same degree, and under the microscope a few of them with an apparently normal structure may be seen. But the contents are not normally developed, and I have tried in vain to obtain fertilization with a large number of flowers. Only by cross-fertilization does O. lata produce seeds, and then as freely as the other species when self-fertilized.
The early ancestors of this flower were self-fertilized; a chance seedling at length, among other continual variations, showed the singular variation of ripening its stigma in advance of its pollen or other condition insuring cross-fertilization thus acquiring a strain of fresh vigor.
Darwin announced the principle that cross-fertilization between the individuals of a species is the plan of Nature, and is practically so universal that it fairly sustains his inference that no hermaphrodite species continually self-fertilized would continue to exist, he made it clear to all who apprehend and receive the principle that a series of plants propagated by buds only must have weaker hold of life than a series reproduced by seed.
It can neither be constrained by selection if it is absent from the beginning, nor does it need any natural or artificial aid if it is present. Most of my new species have proved constant from the first. Whenever possible, the original mutants have been isolated during the flowering period and artificially self-fertilized.
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