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Show 328 FERTILITY OF CROSSED CHAP. IX. than those from the latter, they were not so in any corresponding degree. vVith Nicotiana tho flow?rs fertilised with their own pollen were n1ore proclnetrvo than those crossed with pollen fro1n a slightly different variety; yet the plants raised from the latter seeds were much taller, heavier, and more hardy than those raised from the self-fertilised seeds. On tho other hand, the crossed seedlings of Eschschol tzia wore neither taller nor heavier than the self-fertilised, although the crossed flowers were far 1nore prochlf: .. i ve than the self-fertilised. But the best evidence .f a want of correspondence between the number of c:"ods produced by crossed and self-fertilised flowers, and the vigour of the offspring raised fro1n them, is afforded by the plants of the Brazilian and European stocks of Eschscholtzia, and likewise by certain individual plants of Reseda odorata; for it 1night have boon expected that the seedlings froin plants, the flowers of which were excessively self-sterile, would have profited in a greater degree by a cross, than the seedlings from plants which were moderately or fully self-fertile, and therefore apparently had no need to be crossed. But no such result followed in either case : for instance, the crossed and self-fertilised off: pring fro1n a highly self-fertile plant of Reseda odorata were in average height to each other as 100 to 82; whereas tho si1nilar offspring from an excessively Relf-sterilo plant wore as 100 to 92 in average height. vVith respect to the innate fertility of the plants of crossed and self-fertilised parentage, given in the previous Table D-that is, the nu1nber of soorls produced by both lots when their flowers wore fertilised in the same manner,-nearly the same remarks are applicable, in reference to the absence of any close. eorrespondence between their fertility and powers of CHAP. IX. AND SELF-FERTILISED FLOWERS. 329 growth, as in the case of the plants in the Tables F and G, just considered. Thus the crossed and self-fertilised plants of Ipon1 a, Papaver, Reseda odorata and Liinnanthes were ahnost equally fertile, yet the f;rmer exceeded considerably in height the self-fertilised plants. On the other hand, the crossed and self-fertilised plants of Min1ulus and Pri1nula differed to an extreme degree in innate fertility, but by no means to a corresponding Jegree in height or vigour. In all the cases of self-fertilised flowers included in Tables E, F, and G, these were fertilised with their own pollen; but there is another form of self-fertilisation, viz., by pollen fro1n other flowers on the same plant; but this latter n1ethod made no difference in comparison with the forrner in the nun1ber of seeds prodnced, or only a . slight difference. Neither with Digitalis nor Dianthus were more seeds produced by ·the one 1ne-rt·hod than by the other, to any trustworthy deg1:ee. W 1th Ipomooa rather more seeds, in the pro· portion of 100 to 91, were produced from a cross betwee~ ~owers on the same plant than from strictly self-fert1hsed flowers; but I have reason to suspect that the result was accidentc"tl. With Origanum v·ulgare, however, a cross between flowers on plants propagated b~,. stolons fro1n the saine stock certainly increased slightly their fertility. 'l'his likewise occurred, as we shall see in the next section, with Eschscholtzia, perhaps with Corydalis cava and Oncidium · but not . ' so With Bignonia, Abutilon, Tabernre1nontana, Senecio, and apparently Reseda odorata. Self-sterile Plants. . The cases here to be described might have been Introduced in Table F which o·ives the relative fertility of flowers fertilis~d with 0 their own pollen, and |