Variation in animals and plants . 10 15 20 25 30 35 40Number of Ray-florets. FIG. 14.—Distribution of Ray-florets in the Ox-eye daisy. tinct maxima, corresponding to 3, 5, 8, 10, and 13 petalforms. That these multi-humped curves are actually due toa mingling of two or more local races is proved by an 50 DISCONTINUOUS VARIATION. interesting experiment of De Vries.* He sowed themixed seed of Chrysanthemum segetum obtained fromtwenty different gardens. The topmost flowers of the 8. 0 024 6 8 10 12 14 16 18 20 Number of petals FIG. 15.—Distribution of Petals in Primula officinalis. chief stem of e
Variation in animals and plants . 10 15 20 25 30 35 40Number of Ray-florets. FIG. 14.—Distribution of Ray-florets in the Ox-eye daisy. tinct maxima, corresponding to 3, 5, 8, 10, and 13 petalforms. That these multi-humped curves are actually due toa mingling of two or more local races is proved by an 50 DISCONTINUOUS VARIATION. interesting experiment of De Vries.* He sowed themixed seed of Chrysanthemum segetum obtained fromtwenty different gardens. The topmost flowers of the 8. 0 024 6 8 10 12 14 16 18 20 Number of petals FIG. 15.—Distribution of Petals in Primula officinalis. chief stem of each of the 97 healthy plants obtainedwere examined, and were found to contain the follow-ing numbers of ray florets: Ray florets, 12 13 14 15 16 17 18 19 20 21 22Frequencies, 1 14 13 4 6 9 7 10 12 20 1 *Arch. f. Entwickelungsmechanik, Bd. ii. p. 52, 1896. DISCONTINUOUS VARIATION. 51 Thus there were obviously two forms present, a 13 rayform and a 21 ray form. The seeds from the 12 and13 ray forms were collected and sown next year, theflowers obtained therefrom having the following num-bers of florets: Ray florets, 8 9 10 11 12 13 14 15 16 17 18 19 20 21Frequencies, 2 107 13 94 25 771 2030 That is to say, all trace of the 21 ray form had beeneliminated, and a nearly pure 13 ray form this was so was proved by sowing the seed of someof the 12 rayed plants obtained on this occasion in thefollowing year. It was then found that the frequenciesof occurrence of fl
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