[90]

Phalaris

Heliotropism fairly bright light

Sept 19'

Fig M

[90v]

93

Ipomoea

winter, and in consequence of this the seedlings (20 in number of each kind) became very unhealthy, some growing only a few inches in height and very few to their full height. , so that The result therefore can not hardly be fully trusted; & it It would therefore be of no useless to give the measurements in detail. In order to strike as fair an average as possible, I first excluded all the plants under 50 inches in height, thus rejecting all the most unhealthy plants. The six self-fertilised which thus exceeded 50 inches in height left were on an average 66.86 inches high; the eight intercrossed plants 63.2 high; and the seven Colchester-crossed 65.37 high. So that there was not much difference between the three sets, the self-fertilised plants having a slight advantage. Nor was there any great difference when all only the plants under 36 inches in height were excluded. Nor again, when no single all the plants, was excluded, all the shorter and most however much dwarfed and unhealthy, plants being were included. in the average; and In this latter case the

[Cross and self fertilisation, p. 51: "In my anxiety to see what the result would be, I unfortunately planted the three lots of seeds (after they had germinated on sand) in the hothouse in the middle of winter, and in consequence of this the seedlings (twenty in number of each kind) became very unhealthy, some growing only a few inches in height, and very few to their proper height. The result, therefore, cannot be fully trusted; and it would be useless to give the measurements in detail. In order to strike as fair an average as possible, I first excluded all the plants under 50 inches in height, thus rejecting all the most unhealthy plants. The six self-fertilised thus left were on an average 66.86 inches high; the eight intercrossed plants 63.2 high; and the seven Colchester-crossed 65.37 high; so that there was not much difference between the three sets, the self-fertilised plants having a slight advantage. Nor was there any great difference when only the plants under 36 inches in height were excluded. Nor again when all the plants, however much dwarfed and unhealthy, were included. In this latter case the Colchester-crossed gave the lowest average of all; and if these plants had been in any marked manner superior to the other two lots, as from my former experience I fully expected they would have been, I cannot but think that some vestige of such superiority would have been evident, notwithstanding the very unhealthy condition of most of the plants."]