Plant-breeding; comments on the experiments of Nilsson and Burbank . termediate forms may befound and the variabiHty covers a range, going from onepistil up to a hundred and fifty and sometimes even these altered organs often show anotheranomaly, consisting in a coalescence of some of them, therebyconstituting groups, in which it is difllcult to distinguish andcount the single parts. In extreme cases this coalescencemay be such as to combine all the changed stamens into anarrow cup around the normal capsule, and more com-monly a more or less divided ring of such groups is ob
Plant-breeding; comments on the experiments of Nilsson and Burbank . termediate forms may befound and the variabiHty covers a range, going from onepistil up to a hundred and fifty and sometimes even these altered organs often show anotheranomaly, consisting in a coalescence of some of them, therebyconstituting groups, in which it is difllcult to distinguish andcount the single parts. In extreme cases this coalescencemay be such as to combine all the changed stamens into anarrow cup around the normal capsule, and more com-monly a more or less divided ring of such groups is is easily seen that the variabiHty of this character affordsan excellent material for the study of its dependency onouter influences. We may make sowings under differentcircumstances, giving them a sunny or a shaded place, goodor bad soil, different quahties of manure, watering or keep-ing them dry, protecting the young plants under glass orexposing them to all the effects of the weather, and so we do so we easilv find that all favorable conditions. Fig. 92. Polyccphalous opium poppy. A. Xormal fruit. B. The samecut longitudinally. C, D. Normal stamens. E, F. Stamens transformedinto secondary carpels. G, H, I. Secondary carpels, cut transversely withone. two, and four rows of seeds. ?90 300 PLANT-BREEDING increase the crown of pistillodous stamens, while adverseinfluences reduce the change and thus favor the productionof the normal organs. The same influences, however, govern the degree ofdevelopment of the whole plant, the height and the thicknessof the stem, the size of the flower and the fruit, the numberand the strength of the branches, and even the extent of thefoHage. Hence we may expect a correlation betv^een theabnormality and the growth of all the normal parts, and it isquite easy to control tliis. The best means is to choose theripe capsules. Their size and weight is evidently the resultof the activity of the whole plant, during the whole timeof its li
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