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Show 204 ILLEGITIMATE OFFSPRING OF . 0IIAP. V. gitimately fertilised with pollen frorn the same form, evince a strong, but not exclusiv€, tendency to reproduce the parent-form. When the short-styled form was illegitimately fertilised by the long-styled form (Class V.), and again when the mid-styled was illegitiInately fertilised by the long-styled (Class VI.), in each case the two parent-forms alone were reproduced. As thirty -seven plants were raised from these two unions, we may, with much confidence, believe that it is the rule that plants thus derived usually consist of both parent-forms, but not of the third form. When, however, the mid-styled form was illegitimately fertilised by the longest stamens of the short-sty led (Class VII.), the same rule did not hold good; for the seedlings consisted of all three forms. The illegitimate union fro1n which these latter seedlings were raised is, as previously stated, singularly fertile, and the seedlings themselves exhibited no signs of sterility and grew to their full height. From the consideration of these several facts, and from analogous ones to be given under Oxalis, it seems probable that in a state of . nature the pistil of each form usually receives, through the agency of insects, pollen from the stamens of corresponding height from both the other forms. But the case last given shows that the application of two kinds of pollen is not indispensable for the production of all three forms. Hildebrand has suggested that the cause of all three forms being regularly and naturally reproduced, may be that some of the flowers are fertilised with one kind of pollen, and others on the same plant with the other kind of pollen. Finally, of the three forms, the long-styled evinces somewhat the strongest tendency to reappear amongst the offspring, whether both, or one, or neither of the parents are long-sty led. CHAP. V. HETEROSTYLED TRIMORPHIC PLANTS. 205 TABLE 30. Tabulated results of the fertility of the foregoing illegitimate plants, when legitimately fertilised, generally by illegitimate plants, as described under each experiment. Plants 11, 12 and 13 are excluded, as they were illegitimately fertilised. Normal Standard of Fertility of the three forms, when legitimately and naturally fertilised. Average Maximum Form. Number of Number in Minimum Numb ,r in any ~ccds per any one one Capsule. Capsule. Capsule. Long-styled. 93 159 } No record was kept, as Mid-styled 130 151 all very poor capsules Short-styled 83•5 112 were rejected. CLASS I. and ll.-lllegitimate Plants raised from Long-styled Parents fertilised with pollen from own-form mid-length or shortest stamens. Average Num- Average Maximum Minimum ber of eeds, Number of Plant. Form. Number of Number in Number in expressed as Seed:; per any one any one the percentage Capsule. Capsule. Capsule. of the Normal Standard. --- Plant 1 Long-styled 0 0 0 0 " 2 " 4•5 ? 0 5 ,", 43 " 4·5 ? 0 5 " 4·5 ? 0 5 " 5 " 0 or 1 2 0 0 or 1 " 6 " 0 0 0 0 " 7 " 36·1 47 22 39 . " 8 " 4-1·1 73 11 44 " 9 " 57.1 86 23 61 " 10 " 44·2 69 25 47 I CLASS Ill.-lllegitimate Plants raised from Short-styled Parents fertilised with pollen from O'wn-form shortest stamens. Plant 14 Short-styled 28•3 51 11 ::33 " 15 . " 3~·6 49 20 38 ~ " 16 " 77•8 97 60 94 " 17 Long-styled 76•3 88 57 82 |