The above three lots of seeds, namely, the self-fertilised,
intercrossed, and English-crossed, were planted in an equal state of
germination (having been as usual sown on bare sand) in nine large pots,
each divided into three parts by superficial partitions. Many of the
self-fertilised seeds germinated before those of the two crossed lots,
and these were of course rejected. The seedlings thus raised are the
great-grandchildren of the plants which grew in Brazil. When they were
from 2 to 4 inches in height, the three lots were equal. They were
measured when four-fifths grown, and again when fully grown, and as
their relative heights were almost exactly the same at these two ages, I
will give only the last measurements. The average height of the nineteen
English-crossed plants was 45.92 inches; that of the eighteen
intercrossed plants (for one died), 43.38; and that of the nineteen
self-fertilised plants, 50.3 inches. So that we have the following
ratios in height:--
The English-crossed to the self-fertilised plants, as 100 to 109.
The English-crossed to the intercrossed plants, as 100 to 94.
The intercrossed to the self-fertilised plants, as 100 to 116.
After the seed-capsules had been gathered, all these plants were cut
down close to the ground and weighed. The nineteen English crossed
plants weighed 18.25 ounces; the intercrossed plants (with their weight
calculated as if there had been nineteen) weighed 18.
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