his notion, indeed, is wholly at variance with all that we know of
hybrid generation; for the phenomena entitle us to affirm, that had the
types been at first somewhat distinct, _no cross-breeds would ever have
been produced_, much less those prolific races which we now recognize as
distinct species.

In regard, moreover, to the permanent propagation of hybrid races among
animals, insuperable difficulties present themselves, when we endeavor
to conceive the blending together of the different instincts and
propensities of two species, so as to insure the preservation of the
intermediate race. The common mule, when obtained by human art, may be
protected by the power of man; but, in a wild state, it would not have
precisely the same wants either as the horse or the ass; and if in
consequence of some difference of this kind, it strayed from the herd,
it would soon be hunted down by beasts of prey, and destroyed.

If we take some genus of insects, such as the bee, we find that each of
the numerous species has some difference in its habits, its mode of
collecting honey, or constructing its dwelling, or providing for its
young, and other particulars. In the case of the common hive bee, the
workers are described, by Kirby and Spence, as being endowed with no
less than thirty distinct instincts.[835] So also we find that, amongst
a most numerous class of spiders, there are nearly as many different
modes of spinning their webs as there are species. When we recollect how
complicated are the relations of these instincts with co-existing
species, both of the animal and vegetable kingdoms, it is scarcely
possible to imagine that a bastard race could spring from the union of
two of these species, and retain just so much of the qualities of each
parent stock as to preserve its ground in spite of the dangers which
surround it.

We might also ask, if a few generic types alone have been _created_
among insects, and the intermediate species have proceeded from
hybridity, where are those original types, combining, as they ought to
do, the elements of all the instincts which have made their appearance
in the numerous derivative races? So also in regard to animals of all
classes, and of plants; if species are in general of hybrid origin,
where are the stocks which combine in themselves the habits, properties,
and organs, of which all the intervening species ought to afford us mere
modifications?

_Recapitulation of the arguments from hyb