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Show 198 ILLEGITIMATE OFFSPRING OF CHAP. v. 131 and a minimum of 63: hence this plant did not produce quite 80 per cent. of the normal number of seeds. ·Twelve flowers were artificially and legitimately fertilised with pollen from a legitimate long-styled plant, and yielded from nine capsules an average of 116 ·I seeds, which were finer than in the previous case, with a maximum of 135 and a minimum of 75; so that, as with Plant 17, pollen from a legitimate plant increased the fertility, but did not bring it up to the full standard. Plant 19. This mid-styled plant, fertilised in the same manner and at the same period as the last, yielded an average from ten capsules of 73·4 seeds, with a maximum of 87 and a minimum of 64: hence this plant produced only 56 per cent. of the full number of seeds. Thirteen flowers were artificially and legitimately fertilised with pollen from a legitimate long-styled plant, and yielded ten capsules with an average of 95 · 6 seeds ; so that the application of pollen from a legitimate plant added, as in the two previous cases, to the fertility, but did not bring it up to the proper standard. Plant 20. This long-styled plant, of the same parentage with the two last mid-styled plants, and freely fertilised in the same manner, yielded an average from ten capsules of 69 · 6 seeds, with a maximum of 83 and a minimum of 52 : hence this plant produced 75 per cent. of the full number of seeds. CLASS V. Illegitimate Plants raised from a Short-styled Parent fertilised with pollen from the mid-length stamens of the long-style~ form. In the four previous classes, plants raised from the three forms fertilised with pollen from either the longer or shorter stamens of the same form, but generally not from the same plant, have been described. Six other illegitimate unions are possible, namely, between the three forms and the stamens in the other two forms which do not correspond in height with their pistils. But I succeeded in raising plants from only three of these six unions. From one of the1n, forming the present Class V., twelve plants were raised; these consisted of eight short-sty led, and four long-sty led plants, CHAP. V. HETEROSTYLED TRIMORPHIC PLANTS. 199 with not one mid-styled. These twelve plants never attained quite their full and proper height, but by no means deserved to be called dwarfs. The anthers in some of the flowers were contabescent. One plant was remarkable from all the longer stamens in every flower and from many of the shorter ones having their anthers in this condition. The pollen of four other plants, in which none of the anthers were contabescent, was examined; in one a moderate number of grains were minute and shrivelled, but in the other three they appeared perfectly sound. With respect to the power of producing seed, five plants (Nos. 21 to 25) were observed : one yielded scarce I y more than half the normal number; a second was slightly infertile; but the three others actually produced a larger average number of seeds, with a higher maximum, than the standard. In my concluding remarks I shall recur to this fact, which at first appears inexplicable. Plant 21. This short-styled plant, freely and legitimately fertilised during 1865 by illegitimate plants, descended from self-fertilised long-, mid- and short-styled parents, yielded an average from ten capsules of 43 seeds, with a maximum of 63 and a minimum of 26': hence this plant, which was the one with all its longer and many of its shorter stamens con tabescent, produced only 52 per cent. of the proper number of seeds. Plant 22. This short-styled plant produced perfectly sound pollen, as viewed under the microscope. During 1866 it was freely and ·legitimately fertilised by other illegitimate plants belonging to the present and the following class, both of which include many highly fertile plants. Under these circumstances it yielded from eight capsules an average of 100 · 5 seeds, with a..maximum of 123 and a minimum of 86; so that it produced 121 per cent. of seeds in comparison with the normal standard. During 1864 it was allowed to be freely and legitimately fertilised by legitimate and illegitimate plants, and yielded an average, from eight capsules, of 104 · 2 seeds, with a maximmn of 125 and a minimum of 90 · consequently it exceeded the normal standard, producing 125 per cent. of seeds. In this |