TABLE 4.24. Lythrum salicaria, mid-styled form.

TABLE 4.24.1. Legitimate union.

12 flowers fertilised by the mid-length stamens of the long-styled. These stamens equal in length the pistil of the mid-styled.

Product of good seed in each capsule.

138 122 149 50 147 151 109 119 133 138 144 0 -

92 percent of these flowers (probably 100 per cent) yielded capsules. Each capsule contained, on an average, 127.3 seeds.

TABLE 4.24.2. Legitimate union.

12 flowers fertilised by the mid-length 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 - 141 104

100 percent of these 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.

TABLE 4.24.3. Illegitimate union.

13 flowers fertilised by the shortest stamens of the long-styled.

83 12 0 19 0 85 seeds small and poor. - 0 44 0 44 0 45 0

54 percent of these flowers yielded capsules. Each capsule contained, on an average, 47.4 seeds; or, excluding capsules with less than 20 seeds, the average is 60.2 seeds.

TABLE 4.24.4. Illegitimate union.

15 flowers fertilised by the longest stamens of the short-styled.

130 86 115 113 14 29 6 17 2 113 9 79 - 128 132 0

93 percent of these 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 seeds.

TABLE 4.24.5. Illegitimate union.

12 flowers fertilised by own-form longest stamens.

92 0 9 0 63 0 - 0 136?* 0 0 0 0

(4/6. * I have hardly a doubt that this result of 136 seeds in Table 4.24.5 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-length stamens of the long-styled form 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 missing, namely at the bottom of Table 4.24.1. 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 that which yielded 136, I do not know what to think. I endeavoured to prevent pollen dropping from an upper to a lower flower, and I tried to remember to wipe the pincers carefully after each fertilisation; but in making eighteen different unions, sometimes on windy days, and pestered by bees and flies buzzing about, some few errors could hardly be avoided. One day I had to keep a third man by me all the time to prevent the bees visiting the uncovered plants, for in a few seconds' time they might have done irreparable mischief. It was also extremely difficult to exclude minute Diptera from the net. In 1862 I made the great mistake of placing a mid-styled and long-styled under the same huge net: in 1863 I avoided this error.)

Excluding the capsule with 136 seeds, 25 percent 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.

TABLE 4.24.6. Illegitimate union.

12 flowers fertilised by own-form shortest stamens.

0 0 0 0 0 0 - 0 0 0 0 0 0

Not one flower yielded a capsule.

Besides the experiments in Table 4.24, I fertilised a considerable number of mid-styled flowers with pollen, taken by a camel's-hair brush, from both the longest and shortest stamens of their own form: only 5 capsules were produced, and these yielded on an average 11.0 seeds.

TABLE 4.25. Lythrum salicaria, short-styled form.

TABLE 4.25.1. Legitimate union.

12 flowers fertilised by the shortest stamens of the long-styled.

Charles Darwin

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