ing season: hence hybrids will generally be
fertilised during each generation by their own individual pollen; and I am
convinced that this would be injurious to their fertility, already lessened
by their hybrid origin. I am strengthened in this conviction by a
remarkable statement repeatedly made by Gaertner, namely, that if even the
less fertile hybrids be artificially fertilised with hybrid pollen of the
same kind, their fertility, notwithstanding the frequent ill effects of
manipulation, sometimes decidedly increases, and goes on increasing. Now,
in artificial fertilisation pollen is as often taken by chance (as I know
from my own experience) from the anthers of another flower, as from the
anthers of the flower itself which is to be fertilised; so that a cross
between two flowers, though probably on the same plant, would be thus
effected. Moreover, whenever complicated experiments are in progress, so
careful an observer as Gaertner would have castrated his hybrids, and this
would have insured in each generation a cross with a pollen from a distinct
flower, either from the same plant or from another plant of the same hybrid
nature. And thus, the strange fact of the increase of fertility in the
successive generations of _artificially fertilised_ hybrids may, I believe,
be accounted for by close interbreeding having been avoided.

Now let us turn to the results arrived at by the third most experienced
hybridiser, namely, the Hon. and {250} Rev. W. Herbert. He is as emphatic
in his conclusion that some hybrids are perfectly fertile--as fertile as
the pure parent-species--as are Koelreuter and Gaertner that some degree of
sterility between distinct species is a universal law of nature. He
experimentised on some of the very same species as did Gaertner. The
difference in their results may, I think, be in part accounted for by
Herbert's great horticultural skill, and by his having hothouses at his
command. Of his many important statements I will here give only a single
one as an example, namely, that "every ovule in a pod of Crinum capense
fertilised by C. revolutum produced a plant, which (he says) I never saw to
occur in a case of its natural fecundation." So that we here have perfect,
or even more than commonly perfect, fertility in a first cross between two
distinct species.

This case of the Crinum leads me to refer to a most singular fact, namely,
that there are individual plants of certain species of Lobelia and of so