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Show 202 ILLEGITIMATE OFFSPRING OF CHAP. v. Plant 29. This long-styled plant was legitimately fertilised durinO' the unfavourable season of 1864, in the manner described 0 . under No. 26, and yielded an average, from ten capsules, of 84· 6 seeds, with a maximum of 132 and a minimum of 47, thus attaining to 91 per cent. of the normal fertility. During the highly favourable season of 1866, when fertilised in the manner described under No. 26, it yielded an average, from nine capsules (one poor capsule having been excluded), of 100 seeds, with a maximum of 121 and a minimum of 77. This plant thus exceeded the normal standard, and produced 107 per cent. of seeds. In both sets of anthers there were a good many bad and shrivelled pollen-grains, but not so many as in the last-described plant. Plant 30. This long-styled plant was legitimately fertilised during 1866 in the manner described under No. 26, and yielded an average, from eight capsules, of 94 seeds, with a maximum of 106 and a minimum of 66; so that it exceeded the normal standard, yielding 101 per cent. of seeds. Plant 31. Some flowers on this long-styled plant were artificially and legitimately fertilised by one of its brother illegitimate mid-styled plants; and five capsules yielded an average of 90 · 6 seeds, with a maximum of 97 and a minimum of 79. Hence, as far as can be judged from so few capsules, this plant attained, under these favourable circumstances, 98 per cent. of the normal standard. CLASS VII. Illegitimate Plants raised from Mid-styled Parents fertilised with pollen from the longest stamens of the short-styled form. It was shown in the last chapter that the union from which these illegitimate plants were raised is far more fertile than any other illegitimate union; for the midstyled parent, when thus fertilised, yielded an average (all very poor capsules being excluded) of 102 · 8 seeds, with a maximum of 130; and the seedlings in the present class likewise have their fertility not at all lessened. Forty plants were raised; and these attained their f~ll height and were covered with seed-capsules. CHAP. V. HETEROSTYLED TRIMORPHIC PLANTS. 203 Nor did I observe any con tabescent anthers. It deserves, also, particular notice that these plants, differently from what occurred in any of the previous classes, consisted of all three forms, namely, eighteen shortstyled, fourteen long-styled, and eight mid-styled plants. As these plants were so fertile, I counted the seeds only in the two following cases. Plant 32. This mid-styled plant was freely and legitimately fertilised during the unfavourable year of 1864, by numerous surrounding legitimate and illegitimate plants. Eight capsules yielded an average of 127 · 2 seeds, with a maximum of 144 and a minimum of 96; so that this plant attained 98 per cent. of the normal standard. Plant 33. This short-styled plant was fertilised in the same manner and at the same time with the last; and ten capsules yielded an average of 113 · 9, with a maximum of 137 and a minimum of 90. Hence this plant produced no less than 137 per cent. of seeds in comparison with the normal standard. Concluding Remarks on the Illegitimate Offspring of the three forms of Lythrum salicaria. From the three forms occurring in approximately equal numbers in a state of nature, and from theresults of sowing seed naturally produced, there is reason to believe that each form, when legitimately fertilised, reproduces all three forms in about equal numbers Now, we have seen (and the fact is a very singular one) that the fifty-six plants produced from the long-styled form, illegitimately fertilised with pollen from the same form (Class I. and II.), were all longstyled. The short-styled form, when self-fertilised (Class III.), produced eight short-styled and one longstyled plant; and the mid-styled form, similarly treated (Class IV.), produced three mid-styled and one longstyled offspring; so that these two forms, when ille- |