There is another way of looking at the subject which partially removes a
difficulty that appears at first sight insuperable, namely, that during the
conversion of an hermaphrodite into a dioecious plant, the male organs must
abort in some individuals and the female organs in others. Yet as all are
exposed to the same conditions, it might have been expected that those which
varied would tend to vary in the same manner. As a general rule only a few
individuals of a species vary simultaneously in the same manner; and there is no
improbability in the assumption that some few individuals might produce larger
seeds than the average, better stocked with nourishment. If the production of
such seeds were highly beneficial to a species, and on this head there can be
little doubt, the variety with the large seeds would tend to increase. (7/1. See
the facts given in 'The Effects of Cross and Self-fertilisation' page 353.) But
in accordance with the law of compensation we might expect that the individuals
which produced such seeds would, if living under severe conditions, tend to
produce less and less pollen, so that their anthers would be reduced in size and
might ultimately become rudimentary. This view occurred to me owing to a
statement by Sir J.E. Smith that there are female and hermaphrodite plants of
Serratula tinctoria, and that the seeds of the former are larger than those of
the hermaphrodite form.
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