The seeds from twelve
capsules thus produced were placed in separate watch-glasses for
comparison; and those from the six crossed capsules appeared to the eye
hardly more numerous than those from the six self-fertilised capsules.
But when the seeds were weighed, those from the crossed capsules
amounted to 1.02 grain, whilst those from the self-fertilised capsules
were only .81 grain; so that the former were either heavier or more
numerous than the latter, in the ratio of 100 to 79.
CROSSED AND SELF-FERTILISED PLANTS OF THE FIRST GENERATION.
Having ascertained, by leaving crossed and self-fertilised seed on damp
sand, that they germinated simultaneously, both kinds were thickly sown
on opposite sides of a broad and rather shallow pan; so that the two
sets of seedlings, which came up at the same time, were subjected to the
same unfavourable conditions. This was a bad method of treatment, but
this species was one of the first on which I experimented. When the
crossed seedlings were on an average half an inch high, the
self-fertilised ones were only a quarter of an inch high. When grown to
their full height under the above unfavourable conditions, the four
tallest crossed plants averaged 7.62, and the four tallest
self-fertilised 5.87 inches in height; or as 100 to 77. Ten flowers on
the crossed plants were fully expanded before one on the self-fertilised
plants.
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