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Show .f54 HETEROSTYLED TRIMORPHIC PLANTS. CHAP. IV. This gives an average of 21· 5 ~eeds per capsule. As we know that the long-styled form, when standing near plants of the other two forms and fertilised by insects, produces on an average 93 seeds per capsule, we ·see that this form, fertilised by its own two pollens, yields only between one-fourth and one-fifth of the. full number of seed. I have spoken as if the plant had received both its own kinds of pollen, and this is, of course, possible; but, from the enclosed position of the shortest stamens, it is much more probable that the stigma received exclusively pollen from the midlength stamens; and this, as may be seen in compartment V. in Table 23, is the more fertile of the two self-unions. TABLE 24.-Mid-styled Form. I. Legitimate union. 12 flowers fertilised by the midlength stamens of the long-styled. These stamens equal in length the pistil of the mid-sty led. Product of good seed in each capsule. 138 122 149 50 147 151 109 119 133 138 144 0 92 per cent. of the flowers (probably 100 per cent.) yielded capsules. Each capsule contained, on an average, 127 · 3 seeds. II. Legitimate union. 12 flowers · fertilised by the midlength stamens of the short-styled. These stamens equal in length the pistil of the mid-styled. Product of good seed in each capsule. 112 109 130 143 143 124 100 145 33 12 l41 104 100 per cent. of the flowers yielded capsules. Each capsule contained, on an average, 108 • 0 seeds ; or, excluding capsules with less than 20 seeds, the average is 116 · 7 seeds. CHAP. IV. LYTHRUM SALICARIA. 155 TABLE 24.-Mid-styled Form-continued. III. Illegitimate union. 13 flowers fertilised by the shortest stamens of the long-styled. 83 12 0 19 0 44 44 45 85{seeds small and poor. 0 0 0 0 54 per cent. of the flowers yielded capsules. Each cap~ule contained, on an average, 47 ·4 seeds ; or, excluding capsules with less than 20 seeds, the average is 60 · 2 seeds. v. Dlegitimate union. 12 flowers fertilised by own-form longest stamens. · 92 0 9 0 63 0 0 136? * 0 0 0 0 Excluding the capsule with 136 seeds, 25 per cent. of the flowers yielded capsules, and each capsule contained, on an average, 54· 6 seeds ; or, excluding capsules with less than 20 seeds, the average is 77 · 5. ; I have hardly a doubt that th1s result of 136 seeds in compartment V. was due to a gross error. The flowers to be fertilised by their own longest stamens were first marked by ''white thread," and those by the mid-leno-th stamens of the long-sty led fgrm by "white silk;'' a flower fertilised in the later manner would have yielded about 136 seeds, and it may be observed that one such pod is IV. Illegitimate union. 15 flowers fertilised by the longest st amens of the short-styled. 130 86 115 113 14 29 6 17 2 113 9 79 128 132 0 93 per cent. of the flowers yielded capsules. Each capsule contained, on an average, 69 · 5 seeds ; or, excluding capsules with less than 20 seeds, the average is 102 · 8. VI. Illegitimate union. 12 flowers fertilised by own-form shortest st amens. 0 0 0 0 0 0 0 0 0 0 0 0 Not one flower yielded a capsule. m1ssmg, viz. at the bottom of compartment I. Therefore I have hardly any doubt that I fertilised a flower marked with ''white thread' ' as if it had been marked with "white silk.'' With respect to the capsule which yielded 92 seeds, in the same column with tl1at which yielded 136, I do not know w bat to think. I endeavoured to prevent pollen dropping from an upper to a lower |