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Show 190 ILLEGITIMATE OFFSPRING OF CHAP. v. dry, and, though the plants '":ere c?pious!~ water.ed, some few apparently suffered In their fertility, whilst others were not in the least affected. The years 1865 and, especially, 1866, were highly favourable. Only a few observations were made during 1867. The results are arranged in classes according to the parentaae of the plants. In each case the average numberb of seeds per capsule is given, generally taken from ten capsules, which, according to my experience, is a nearly sufficient number. The maximum number of seeds in any one capsule is also given ; and this is a useful point of comparison with the normal standard-that is, with the number of seeds produced by legitimate plants legiti1nately fertilised. I will give likewise in each case the mini1num number. When the maximum and 1ninimu1n differ greatly, if no remark is made on the subject, it may be understood that the extremes are so closely connected by intermediate figures that the average is a fair one. Large capsules were always selected for counting, in order to avoid over-estimating the infer- . tility of the several illegitimate plants. In order to judge of the degree of inferiority in fertility of the several illegitimate plants, the following statement of the average and of the maximum number of seeds produced by ordinary or legitimate plants, when legitimately fertilised, so1ne artificially and some naturally, will serve as a standard of comparison, and may in each case be referred to. But I give under each experiment the percentage of seeds produced by the illegitimate plants, in comparison with the standard legitimate number of the same form. For instance, ten capsules fro1n the illegitimate long-styled plant (No. 10), which was legitimately and naturally fertilised by other illegitimate plants, CHAP. V. HETEROSTYLED TRIMORPHIC PLANTS. '191 (' contained on an ~verage 44· 2 seeds; whereas the capsules on legitimate long-styled plants, legiti1nately and naturally fertilised by other legitimate plants, contained on an average 93 seeds. Therefore this illegiti1nate plant yielded only 4 7 per cent. of the full and normal complement of seeds. Standard Nun~ber of Seeds produced by Legitimate Plants of the three Forms, when legitimately fertilised. Long-sty led form : average n urn ber of seeds in each capsule, 93 ; maximum number observed out of twentythree capsules, 159. Mid-styled fonn: average number of seeds, 130; 1naximum number observed out of thirty-one capsules, 151. Short-styled form: average number of seeds, 83 · 5; but we may, for the sake of brevity, say 83; maximum number observed out of twenty-five capsules, 112. CLASSES I. and II. Illegitimate Plants raised from Long-styled Parents fertilised with pollen frO?n the mid-length or the shortest stamens of other plants of the same form. From this union I raised at different ti1nes three lots of illegitimate seedlings, amounting altogether to 56 plants. I must premise that, from not foreseeing the result, I did not keep a memorandum whether the eight plants of the first lot were the product of the mid-length or shortest stamens of the sa1ne form; but I have good reason to believe that they were the product of the latter. These eight plants were 1nuch more dwarfed, and much more sterile•than those in the other two lots. The latter were raised from a long-sty led |