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Show 220 ILLEGITIMATE OFFSPRING OF CIIAP. v. smooth, were either completely surrounded by the anthers, or stood close above them. My son William made drawings for me, by the aid of the camera, of the pollen of one of the above equal-styled plants; and, in accordance with the position of the stamens, the grains resembled in their small size those of the long-styled form. He also examined pollen from two equal- styled plants at Southampton; and in both of them the grains differed extremely in size in the same anthers, a large. number being small and shrivelled, whilst many were fully as large as those of the short-styled form and rather n1ore globular. It is probable that the large size of these grains was due, not to their having assumed the character of the short-styled form, but to monstrosity; for Max Wichura has observed pollen-grains of monstrous size in certain hybrids. The vast number of the small shrivelled grains in the above two cases explains tho fact that, though equal-styled plants are generally fertile in a high degree, yet some of them yield few seeds. I may add that my son compared, in 1875, the grains from two white-flowered plants, in both of which the pistil projected above the anthers, but neither were properly long-styled or equal-styled; and in the one in which the stigma projected most, the grains were in diameter to those in the other plant, in which the stigma projected less, as 100 to 88; whereas the difference between the grains from perfectly characterised long-styled and short-styled plants is as 100 to 57. So that these two plants were in an intermediate condition. To return to the 17 plants i 1 the first line of Table 31: from the relative position of their stigmas and anthers, they could hardly fail to fertilise themselves; and accordingly four of them spontaneously yielded no less than 180 capsules; of these Mr. Horwood selected eight fine capsules for s0wing; and they included on an average 54· 8 seeds, with a maximum of 72. He gave me thirty other capsules, taken by hazard, of which twenty-seven contained good seeds, averaging 35 · 5, with a maximum of 70; but if six poor capsules, each with less than 13 seeds be excluded the averabae rises to 42 · 5. These are higher nu' mbers than 'c ould be ex-pected from either well-characterised form if self-fertilised; and this high degree of fertility accords with the view that the male organs belonged to one form, and the female organs partially to the other form; so that a self-union in the case of the equal-styled variety is in fact a legitimate union. The seed saved from the above seventeen self-fertilised equal- CHAP. V. HETEROSTYLED DIMORPHIC PLANTS. 221 styled plants produced sixteen plants, which all proved equalstyled, and resembled their parents in all the above-specified respects. The stamens, however, in one plant were seated higher up the tube of the corolla than in the true long-styled form; in another plant almost all the anthers were con tabescent. These sixteen plants were the grandchildren of the four original plants, which it is believed were equal-styled; so that this abnormal condition was faithfully transmitted, probably through three, and certainly through two generations. The fertility of one of these grandchildren was carefully observed: six flowers were fertilised with pollen from the same flower, and produced six capsules, containing on an average 68 seeds, with a maximum of 82, and a minimum of 40. Thirteen capsules spontaneously self-fertilised yielded an average of 53· 2 seeds, with the astonishing maximum in one of 97 seeds. In no legitimate union has so high an average as 68 seeds been observed by me, or nearly so high a maximum as 82 and ~7. These plants, therefore, not only have lost their proper heterosty led structure and peculiar functional powers, but have acquired an abnormal grade of fertility- unless, indeed, their high fertility may be accounted for by the stigmas receiving pollen from the circumjacent anthers at exactly the most favourable period. With respect to Mr. Duck's lot in Table 31, seed was saved from a single plant, of which the form was not observed, and this produced nine equal-styled and twenty long-styled plants. The equal-styled resembled in all respects those previously described; and eight of their capsules spontaneously self-fertilised contained on an average 44 · 4 seeds, with a maximum of 61 and a minimum of 23. In regard to the twenty long-styled plants, the pistil in some of the flowers did not project quite so high as in ordinary long-styled flowm·s; and the stigmas, though pi'operly elongated, were smooth; so that we have here a slight approach in stl'ucture to the pistil of the short-styled form. Some of these long-styled plants also approached the equal-styled in function; for one of them produced no less than fifteen spontaneously self-fertilised capsules, and of these eight contained, on an average, 31 · 7 seeds, with a maximum of 61. This average would be rather low for a long-styled plant artificially fertilised with its own pollen, but is high for one spontaneously self-fertilised. For instance, thirty-four capsules produced by the illegitimate grandchildren of a long-styled plant, spontaneously self-fertilised, contained |