over
a flower's own pollen, adds the very significant remark,[121] "When
distinct _species_ are crossed, the case is directly the reverse, for a
plant's own pollen is almost always prepotent over foreign pollen."

Again he adds:[122] "I believe from observations communicated to me by Mr.
Hewitt, who has had great experience in hybridizing pheasants and fowls,
that the early death of the embryo is a very frequent cause of sterility in
first crosses. Mr. Salter has recently given the results of an examination
of about 500 eggs produced from various crosses between three species of
Gallus and their hybrids. The majority of these eggs had been fertilized,
and in the majority of the fertilized eggs the embryos either had been
partially developed and had then aborted, or had become nearly mature, but
the young chickens had been unable to break through the shell. Of the
chickens which were born, more than four-fifths died within the first few
days, or at latest weeks, 'without any obvious cause, apparently from mere
inability to live,' so that from 500 eggs only twelve chickens were reared.
The early death of hybrid embryos probably occurs in like manner with
plants, at least it is known that hybrids raised from very distinct species
are sometimes weak and dwarfed, and perish at an early age, of which fact
Max Wichura has recently given some striking cases with hybrid willows."

Mr. Darwin objects to the notion that there is any special sterility
imposed to check specific intermixture and change, saying,[123] "To grant
to species the special power of producing hybrids, and then to stop {125}
their further propagation by different degrees of sterility, not strictly
related to the facility of the first union between their parents, seems a
strange arrangement."

But this only amounts to saying that the author himself would not have so
acted had he been the Creator. A "strange arrangement" must be admitted
anyhow, and all who acknowledge teleology at all, must admit that the
strange arrangement was designed. Mr. Darwin says, as to the sterility of
species, that the cause lies exclusively in their sexual constitution; but
all that need be affirmed is that sterility is brought about somehow, and
it is undeniable that "crossing" _is_ checked. All that is contended for is
that there _is_ a bar to the intermixture of _species_, but not of
_breeds_; and if the conditions of the generative products are that bar, it
is enough for the a