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This fact was, of course, most distasteful to the systematists of his time and even for a long period afterwards they attempted to discredit it. Milde and many others have opposed these new ideas with some temporary success. Only of late has the school of Jordan received due recognition, after Thuret, de Bary, Rosen and others tested its practices and openly pronounced for them.
Thuret has observed the same fact with certain sea-weeds or Fuci. Gartner, moreover, found that this difference of facility in making reciprocal crosses is extremely common in a lesser degree.
Thuret has observed the same fact with certain sea-weeds or Fuci. Gartner, moreover, found that this difference of facility in making reciprocal crosses is extremely common in a lesser degree.
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.
Thuret has observed the same fact with certain sea-weeds or Fuci. Gärtner, moreover, found that this difference of facility in making reciprocal crosses is extremely common in a lesser degree.
This process may be repeated ad infinitum, unless we get to true organic atoms, the true gemmules, whatever they may be, and they necessarily will be incapable of any process of spontaneous fission. It is remarkable that Mr. Darwin brings forward in support of gemmule fission, the observation that "Thuret has seen the zoospore of an alga divide itself, and both halves germinate."
Jordan made numerous cultures, some of which lasted ten or twelve years; Thuret has verified the assertion concerning their constancy by cultures extending over seven years in some instances; Villars and de Bary made numerous trials of shorter duration. All agree as to the main points.
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