[13]

Anheliotropism

Bignonia capreolata

Tendril Right Hand

July 21 & 22 1878 after turning pot round

Tracing III

 

[data not transcribed]

[13v]

41

Introduction

over the whole surface of the stigmas of 64 other flowers. In order to vary the experiment half the flowers of both lots were on plants produced from self-fertilised seeds, and the other half on plants from crossed seeds. The 64 flowers with an excess of pollen yielded 61 capsules; and excluding four capsules, each of which contained only a single poor seed, the remainder contained on an average 5.07 seeds per capsule. The 64 flowers with only a little pollen placed on one side of the stigma yielded 63 capsules, and excluding one from the same cause as before, the remainder contained on an average 5.129 seeds. So that the flowers fertilised with little (13) pollen yielded rather more capsules and seed than those fertilised with an excess; but the difference is too slight to be of any significance. Moreover the seeds produced by the flowers with an excess of pollen, were a little heavier of the two; for 170 of them weighed 79.67 grams, whilst 170

[Cross and self fertilisation, pp. 24-5: "Accordingly a very small mass of pollen-grains was placed on one side of the large stigma in sixty-four flowers of Ipomoea purpurea, and a great mass of pollen over the whole surface of the stigma in sixty-four other flowers. In order to vary the experiment, half the flowers of both lots were on plants produced from self-fertilised seeds, and the other half on plants from crossed seeds. The sixty-four flowers with an excess of pollen yielded sixty-one capsules; and excluding four capsules, each of which contained only a single poor seed, the remainder contained on an average 5.07 seeds per capsule. The sixty-four flowers with only a little pollen placed on one side of the stigma yielded sixty-three capsules, and excluding one from the same cause as before, the remainder contained on an average 5.129 seeds. So that the flowers fertilised with little pollen yielded rather more capsules and seeds than did those fertilised with an excess; but the difference is too slight to be of any significance. On the other hand, the seeds produced by the flowers with an excess of pollen were a little heavier of the two; for 170 of them weighed 79.67 grains, whilst 170 seeds from the flowers with very little pollen weighed 79.20 grains. Both lots of seeds having been placed on damp sand presented no difference in their rate of germination."]