feet high it had grown equal; it then grew a little taller than the
self-fertilised plant, but was ultimately beaten by it to the extent of
half an inch, as shown in Table 2/7. I was so much surprised at this
case that I saved the self-fertilised seeds of this plant, which I will
call the "Hero," and experimented on its descendants, as will hereafter
be described.

Besides the plants included in Table 2/7, nine crossed and nine
self-fertilised plants of the same lot were raised in two other pots, 4
and 5. These pots had been kept in the hothouse, but from want of room
were, whilst the plants were young, suddenly moved during very cold
weather into the coldest part of the greenhouse. They all suffered
greatly, and never quite recovered. After a fortnight only two of the
nine self-fertilised seedlings were alive, whilst seven of the crossed
survived. The tallest of these latter plants when measured was 47 inches
in height, whilst the tallest of the two surviving self-fertilised
plants was only 32 inches. Here again we see how much more vigorous the
crossed plants are than the self-fertilised.

CROSSED AND SELF-FERTILISED PLANTS OF THE SEVENTH GENERATION.

These were raised as heretofore with the following result:--

TABLE 2/8. Ipomoea purpurea (Seventh Generation).

Heights of Plants in inches:

Column 1: Number (Name) of Pot.

Column 2: Crossed Plants.