I should add that the legitimate unions in both cases yielded, as might have been expected, many more seeds than the illegitimate unions. The seedlings whilst half-grown presented no difference in height on the two sides of the several pots. When fully grown they were measured to the tips of their longest leaves, and the result is given in Table 6/95.
TABLE 6/95. Primula sinensis.
Heights of plants measured in inches.
Column 1: Number (Name) of Pot.
Column 2: Plants from legitimately Crossed seeds.
Column 3: Plants from illegitimately Self-fertilised seeds.
Pot 1 : 8 2/8 : 8. From short-styled mother.
Pot 2 : 7 4/8 : 8 5/8. From short-styled mother.
Pot 3 : 9 5/8 : 9 3/8. From long-styled mother.
Pot 4 : 8 4/8 : 8 2/8. From long-styled mother.
Pot 5 : 9 3/8 : 9. From illegitimate short-styled mother.
Pot 6 : 9 7/8 : 9 4/8. From illegitimate short-styled mother.
Pot 7 : 8 4/8 : 9 4/8. From illegitimate long-styled mother.
Pot 8 : 10 4/8 : 10. From illegitimate long-styled mother.
Total : 72.13 : 72.25.
In six out of the eight pots the legitimately crossed plants exceeded in height by a trifle the illegitimately self-fertilised plants; but the latter exceeded the former in two of the pots in a more strongly marked manner. The average height of the eight legitimately crossed plants is 9.01, and that of the eight illegitimately self-fertilised 9.03 inches, or as 100 to 100.2. The plants on the opposite sides produced, as far as could be judged by the eye, an equal number of flowers. I did not count the capsules or the seeds produced by them; but undoubtedly, judging from many previous observations, the plants derived from the legitimately crossed seeds would have been considerably more fertile than those from the illegitimately self-fertilised seeds. The crossed plants, as in the previous case, flowered before the self-fertilised plants in all the pots except in Pot 2, in which the two sides flowered simultaneously; and this early flowering may, perhaps, be considered as an advantage.
27. POLYGONEAE.--Fagopyrum esculentum.
This plant was discovered by Hildebrand to be heterostyled, that is, to present, like the species of Primula, a long-styled and a short-styled form, which are adapted for reciprocal fertilisation. Therefore the following comparison of the growth of the crossed and self-fertilised seedlings is not fair, for we do not know whether the difference in their heights may not be wholly due to the illegitimate fertilisation of the self-fertilised flowers.
I obtained seeds by legitimately crossing flowers on long-styled and short-styled plants, and by fertilising other flowers on both forms with pollen from the same plant. Rather more seeds were obtained by the former than by the latter process; and the legitimately crossed seeds were heavier than an equal number of the illegitimately self-fertilised seeds, in the ratio of 100 to 82. Crossed and self-fertilised seeds from the short-styled parents, after germinating on sand, were planted in pairs on the opposite sides of a large pot; and two similar lots of seeds from long-styled parents were planted in a like manner on the opposite sides of two other pots. In all three pots the legitimately crossed seedlings, when a few inches in height, were taller than the self-fertilised; and in all three pots they flowered before them by one or two days. When fully grown they were all cut down close to the ground, and as I was pressed for time, they were placed in a long row, the cut end of one plant touching the tip of another, and the total length of the legitimately crossed plants was 47 feet 7 inches, and of the illegitimately self-fertilised plants 32 feet 8 inches. Therefore the average height of the fifteen crossed plants in all three pots was 38.06 inches, and that of the fifteen self-fertilised plants 26.13 inches; or as 100 to 69.
28. CHENOPODIACEAE.--Beta vulgaris.
A single plant, no others growing in the same garden, was left to fertilise itself, and the self-fertilised seeds were collected.