. Carnegie Institution of Washington publication. 34 MUTANTS AND HYBRIDS OF THE OENOTHERAS. The rosettes of 0. lamarckiana and 0. rubrinervis which failed to send up flowering shoots in 1903 endured the following winter, which was of maximum severity, and began growth in a normal manner in the spring of 1904, but were uprooted to make room for a new series of experiments. No actual difference has been found in the power of producing pollen among the parent-form, the mutants grown in the New York Botanical Garden, and the other American species. All produce an abundant crop of pollen, and show
. Carnegie Institution of Washington publication. 34 MUTANTS AND HYBRIDS OF THE OENOTHERAS. The rosettes of 0. lamarckiana and 0. rubrinervis which failed to send up flowering shoots in 1903 endured the following winter, which was of maximum severity, and began growth in a normal manner in the spring of 1904, but were uprooted to make room for a new series of experiments. No actual difference has been found in the power of producing pollen among the parent-form, the mutants grown in the New York Botanical Garden, and the other American species. All produce an abundant crop of pollen, and show many faulty grains. 0. rubrinervis was found to produce a greater number of capsules, and the seeds ger- minated more readily than those of the parent-form, the plants reaching maturity earlier than 0. lamarckiana. 0. gigas, on the other hand, grows more slowly than the parent-form, as stated above, although it. Fig. 2. Seedlings of Onagra gigas, about five weeks old, showing variations in forms of leaves. produces seeds abundantly, which show a high percentage of germina- tion. Both species are supposed by De Vries to be quite equal to the parental type in vigor, or perhaps to excel it. The latter suggestion is supported by the marked reproductive capacity of these forms in hybridizations When crossed with the parental form or with other mutants, the dominance of the characters of 0. gigas and O. rubri- nervis is especially marked, most so in the case of 0. gigas. In continuation of the work carried on in previous cultures obser- vations of 0. gigas were made for the purpose of placing on record an exact description of its characteristics as grown in America. The formal descriptions of the parental type andO. rubrinervis and 0. nanella have already proved useful in the various phases of the present investi- gation. (MacDougal, 1903.). Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appe
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