pollen from the same individual plant; and in the case of hybrids from
heterostyled species the opposite forms should be crossed. Fourthly and lastly,
by the supposed hybrids being much more fertile when crossed with either pure
parent-species than when crossed inter se, but still not as fully fertile as the
parent-species.

For the sake of ascertaining the two latter points, I transplanted a group of
wild oxlips into my garden. They consisted of one long-styled and three short-
styled plants, which, except in the corolla of one being slightly larger,
resembled each other closely. The trials which were made, and the results
obtained, are shown in tables 2.14, 2.15, 2.16, 2.17 and 2.18. No less than
twenty different crosses are necessary in order to ascertain fully the fertility
of hybrid heterostyled plants, both inter se and with their two parent-species.
In this instance 256 flowers were crossed in the course of four seasons. I may
mention, as a mere curiosity, that if any one were to raise hybrids between two
trimorphic heterostyled species, he would have to make 90 distinct unions in
order to ascertain their fertility in all ways; and as he would have to try at
least 10 flowers in each case, he would be compelled to fertilise 900 flowers
and count their seeds. This would probably exhaust the patience of the most
patient man.

TABLE 2.14. Crosses inter se between the two forms of the common Oxlip.

Column 1: Illegitimate union.
Short-styled oxlip, by pollen of short-styled oxlip: 20 flowers fertilised, did
not produce one capsule.

Column 2: Legitimate union.
Short-styled oxlip, by pollen of long-styled oxlip: 10 flowers fertilised, did
not produce one capsule.