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Show VIOLA TRICOLOR. CHAP. IV. 126 . . ·enerally flowered first, and produced height of the self-fertihsedil g fertilised capsules. ten times as many natura y TABLE XLI. Viola tr·icolor. I 1- Crossed Plants. Self-fertilised Plants. No. of Pot. ,- -- Inches. Inches. I. 8~ 0~ 7 4 2t·1l tl 12 I 5 B -- 1- 6 II. 5 4 4 4~ 31 8 -- -- -- - - ·- 3b III. 9a 3~ 1~ 8~ 0~ -·- - -- - - 1- 21 IV. 4~ g 4i 1a 4 21g ----- - - - - V. 6 3 3~ 1~ - Total in inches. I 78•13 'I 33·25 By the early part of the summer of 18~0 !~e ;~:~e~~;~n;~!:~ all the five clumps had grown and spr~a between them was the self-fertilised, that any comparison d 'th a sheet of superfluous. The crosse d plants w.e .r e covere WhI ich was much bloom whilst only a single self-fertilised plant, w l d self- ' . fl. . d The cro sec an finer than any of Its brethren, owm~l . tted toaether on the fertilised plants had now grown a .. rna . b tinO' them; resp~ctive sides of thh~ shu~ertcla1p:;:I~~~:;t~~i;_fe;~~ised plant, and In the clump w IC Inc u c sed lants was I estimated that the surface covered by the eros sefr-fertilised about nine times as large as that. co:vered by th~ssed over the plants. The extraordiifary supenonty of the cr d bt due to self-fertilised plants in all five clumps, w~s no d ou t e over· the crossed plants at fi rst h avi· ng h a d a deCided a van ag f their the self-fertilised, and th~n ro bbI. ng tJ lem mo-.r.. e 'and more o 1 uld remember food during the succeeding seasonR. But we s 10 CHAP. IV. VIOLA TRICOLOR. 127 that the same result would follow in a state of nature even to a greater degree; for my plants grew in ground kept clear of weeds, so that the self-fertilised had to compete only with the crossed plants; whereas the whole surface of the ground is naturally covered with various kinds of plants, all of which have to struggle together for existence. The ensuing winter was very severe, and in the following spring (1871) the plants wore again examined. All the selffertilised were now dead, with the exception of a single branch on ·one plant, which bore on its summit a minute rosette of leaves about as large as a pea. On the other hand, all the crossed plants without exception wore growing vigorously. So that the self-fertilised plants, besides their inferiority in other respects, were more tender. Another experiment was now tried for the sake of ascertaining how far the superiority of the crossed plants, or to speak more correctly, the inferiority of the self-fertilised· plants, would be transmitted to their offspring. The one crossed and one selffertilised plant, which were first raised, had been turned out of their pot and planted in the open ground. Both produced an abundance of very fine capsules, from which fact we may safely conclude that they had be.en cross-fertilised by insects. Seeds from both, after germinating on sand, were planted in pairs on the opposite sides of throe pots. The naturally crossed seedlings TABLE XLII. Viola tr ... co.lor: seedlings from cross(d and self-fertilised Plants, the 'parents of both sets havin,r; b en lift to be naturally fertilised. Naturally crossed Naturally crossed No. of Pot. Plants from artifi- Plants from self-cially cro cd Phnt. fertilised PlatJt:>. - Inches. Inches. I. I 10-1g 9~ 11~ 8~ II. I 13i gg I 10 11~ - - --- -- III. I 14~ 11~ 13~ 11 ~ - -- - -- Total in inches. 75•38 I 61•88 |