Nor ought we to marvel if all the contrivances in nature be not, as far as we can judge, absolutely perfect; as in the case even of the human eye; or if some of them be abhorrent to our ideas of fitness.

We need not marvel at the sting of the bee, when used against the enemy, causing the bee's own death; at drones being produced in such great numbers for one single act, and being then slaughtered by their sterile sisters; at the astonishing waste of pollen by our fir-trees; at the instinctive hatred of the queen-bee for her own fertile daughters; at ichneumonidae feeding within the living bodies of caterpillars; and at other such cases.

The wonder, indeed, is, on the theory of natural selection, that more cases of the want of absolute perfection have not been detected.
The complex and little known laws governing the production of varieties are the same, as far as we can judge, with the laws which have governed the production of distinct species.

In both cases physical conditions seem to have produced some direct and definite effect, but how much we cannot say.

Thus, when varieties enter any new station, they occasionally assume some of the characters proper to the species of that station.