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Updated: May 8, 2025
De Bary, Thuret, Rosen and many others confirmed this result, and repeated the pedigree-cultures of Jordan. Every type is constant and remains unchanged in successive generations. The anthers open in the flower-buds and pollinate the stigmas before the expansion of the flowers, thus assuring self-fertilization. Moreover, these inconspicuous little flowers are only sparingly visited by insects.
They have been brought into cultivation many times, but the minutest distinction of their elementary forms is required to attain the highest success. In concluding, I will point out a very interesting difficulty, which in some cases impedes the clear understanding of elementary species. It is the lack of self-fertilization.
The plant seldom sets seed in this vicinity, but seems to depend rather upon its tuber-like rootstocks in which the leaves lie curled all through the winter. The hepatica attracts pollen-feeding flies, female hive-bees and the earliest butterflies, and is thus cross-fertilized to some extent; but it is thought also to be able to effect self-fertilization.
And he shows how this species is even wonderfully and specially modified to effect self-fertilization. In the work just referred to Mr.
He meant to put a stop to this humiliating scene. As the other, regardless of his pleadings, continued to babble dithyrambic nonsense concerning glucose and self-fertilization and artificial manures and inflorescence and Assyrian bas-reliefs and Stilton cheese, he suddenly gripped his arm and pulled him, with a crash, into his chair. "Sit down, you double-distilled owl!"
Among ordinary flowers this intervention of the insect is largely a preferable intention, and though almost invariably fulfilled, a large proportion of flowers still retain, as a dernier ressort, the power of at least partial self-fertilization and perpetuity in the absence or neglect of their insect counterpart.
One instance however, is very remarkable, and we have already dealt with it, when treating of constant varieties, and of the lack of vicinism in the case of species with exclusive self-fertilization. It is the "Nepaul-barley" or Hordeum trifurcatum.
O. biennis and O. muricata have their stigmas in immediate contact with the anthers within the flower-buds, and as the anthers open in the morning preceding the evening of the display of the petals, fecundation is usually accomplished before the insects are let in. But in O. lamarckiana no such self-fertilization takes place.
The sex-difference in organisms, the “abhorrence of self-fertilization” which Mr. Darwin speaks of as so conspicuous and inexplicable a phenomenon, is but one example of the sway of a law which as action and reaction, thesis and antithesis, is common to both elementary motion and thought. The fertile and profound fancy of Greece delighted to prefigure this truth in significant symbols and myths.
I have already mentioned its small corolla, surpassed by the lobes of the calyx and its capacity of self-fertilization. It has still other curious differentiating characters; the pollen grains, which are square in V. tricolor, are five-sided in V. arvensis. Some transgressive fluctuating variability may occur in both cases through the admixture of pollen-grains.
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