The long-styled oxlip was more fertile than the three short-styled oxlips, and
about half its pollen-grains appeared sound. It bore no seed when legitimately
fertilised by the short-styled oxlips; but this no doubt was due to the badness
of the pollen of the latter; for when illegitimately fertilised (Table 2.14) by
its own pollen it produced some good seeds, though much fewer than self-
fertilised cowslips or primroses would have produced. The long-styled oxlip
likewise yielded a very low average of seed, as may be seen in the third
compartment of Tables 2.15 to 2.18, when illegitimately fertilised by, and when
illegitimately fertilising, pure cowslips and primroses. The four corresponding
legitimate unions, however, were moderately fertile, and one (namely that
between a short-styled cowslip and the long-styled oxlip in Table 2.17) was
nearly as fertile as if both parents had been pure. A short-styled primrose
legitimately fertilised by the long-styled oxlip (Table 2.18) also yielded a
moderately good average, namely 48.7 seeds; but if this short-styled primrose
had been fertilised by a long-styled primrose it would have yielded an average
of 65 seeds. If we take the ten legitimate unions together, and the ten
illegitimate unions together, we shall find that 29 per cent of the flowers
fertilised in a legitimate manner yielded capsules, these containing on an
average 27.
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