First, in regard to the transmission of form and colour. The parent-plant was long-styled, and of a rich purple colour. From the self-fertilised seed 23 plants were raised; of these 18 were purple of different shades, with two of them a little streaked and freckled with yellow, thus showing a tendency to reversion; and 5 were yellow, but generally with a brighter orange centre than in the wild flower. All the plants were profuse flowerers. All were long-styled; but the pistil varied a good deal in length even on the same plant, being rather shorter, or considerably longer, than in the normal long-styled form; and the stigmas likewise varied in shape. It is, therefore, probable that an equal- styled variety of the primrose might be found on careful search; and I have received two accounts of plants apparently in this condition. The stamens always occupied their proper position low down in the corolla; and the pollen-grains were of the small size proper to the long-styled form, but were mingled with many minute and shrivelled grains. The yellow-flowered and the purple-flowered plants of this first generation were fertilised under a net with their own pollen, and the seed separately sown. From the former, 22 plants were raised, and all were yellow and long-styled. From the latter or the purple-flowered plants, 24 long-styled plants were raised, of which 17 were purple and 7 yellow. In this last case we have an instance of reversion in colour, without the possibility of any cross, to the grandparents or more distant progenitors of the plants in question. Altogether 23 plants in the first generation and 46 in the second generation were raised; and the whole of these 69 illegitimate plants were long-styled!
Eight purple-flowered and two yellow-flowered plants of the first illegitimate generation were fertilised in various ways with their own pollen and with that of the common primrose; and the seeds were separately counted, but as I could detect no difference in fertility between the purple and yellow varieties, the results are run together in Table 5.32.
TABLE 5.32. Primula vulgaris.
Column 1: Nature of plant experimented on, and kind of union. Column 2: Number of flowers fertilised. Column 3: Number of capsules produced. Column 4: Average Number of seeds per capsule. Column 5: Maximum Number of seeds in any one capsule. Column 6: Minimum Number of seeds in any one capsule.
Purple- and yellow-flowered illegitimate long-styled plants, ILLEGITIMATELY fertilised with pollen from the same plant : 72 : 11 : 11.5 : 26 : 5.
Purple- and yellow-flowered illegitimate long-styled plants, ILLEGITIMATELY fertilised with pollen from the common long-styled primrose : 72 : 39 : 31.4 : 62 : 3.
Or, if the ten poorest capsules, including less than 15 seeds, be rejected, we get: 72 : 29 : 40.6 : 62 : 18.
Purple- and yellow-flowered illegitimate long-styled plants, LEGITIMATELY fertilised with pollen from the common short-styled primrose : 26 : 18 : 36.4 : 60 : 9.
Or, if the two poorest capsules, including less than 15 seeds, be rejected, we get: 26 : 16 : 41.2 : 60 : 15.
The long-styled form of the common primrose ILLEGITIMATELY fertilised with pollen from the long-styled illegitimate purple- and yellow-flowered plants: 20 : 14 : 15.4 : 46 : 1.