The mutation theory; experiments and observations on the origin of species in the vegetable kingdom . uggests, to ultimately obtain the un-fasciated original form of this highly moditied plant.^But according to the view laid down in this book, a mu-tation would be necessary for this;and, so far as we know, these ap-pear only very seldom and fortui-tously, unless we happen to meetwith a plant in a mutational the years 1893-1897 Iendeavored to obtain a race devoidof fasciations, but in vain; and in-asmuch as the general rule is thatfa\orable circumstances increasethe production of
The mutation theory; experiments and observations on the origin of species in the vegetable kingdom . uggests, to ultimately obtain the un-fasciated original form of this highly moditied plant.^But according to the view laid down in this book, a mu-tation would be necessary for this;and, so far as we know, these ap-pear only very seldom and fortui-tously, unless we happen to meetwith a plant in a mutational the years 1893-1897 Iendeavored to obtain a race devoidof fasciations, but in vain; and in-asmuch as the general rule is thatfa\orable circumstances increasethe production of the anomalies,and as correspondingly the worstnourished and w^eakest individualshave alwavs borne the smallest fas-ciations, I w^as ultimately o1)ligedto give up the experiment, becausemy strain gradually became verymuch debilitated without, however,producing the desired result. In 1893 I raised about fifty])lants from bought seed, but diflnot make any detailed record ofthem. Most of them producedcombs in every degree of de\el-opment,^ but usually of small size,5 — 10 centimeters broad or Fig. 117. Celosia cris-tata. Top of a plantabout Vz meter high;the stem was muchbranched and its in-florescences were ear-shaped l)ut mostly withcomb-shaped tops. ^ n. Solms-Laubach, Bof. Zcitung, 1900, p. 42. ^ The plane of the fasciation is the median plane of the cotyle-dons ; and this is also the case in Crcpis biennis. This fact mightbe used as a starting point for an inquiry into the ontogeny of fas-ciations. The Significance of I he Atavists. 519 Six plants had a terminal spike at the top of the mainstem with a small comh; in six others this comb was ab-sent, althongh small fasciations occurred here and thereamongst the lateral branches. These six plants wereselected as seed-parents, and from their seeds 1 obtainedthe second generation (1894), in which about half theindividuals bore terminal spikes without a comb. Therewere 41 of these. The remaining 55 had combs rangingfrom 1-
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