The weight of this objection is obvious; but our ignorance of the
conditions of fertility and sterility, the want of carefully conducted
experiments extending over long series of years, and the strange
anomalies presented by the results of the cross-fertilization of many
plants, should all, as Mr. Darwin has urged, be taken into account in
considering it.

The seventh objection is that we have already discussed (_supra_, p.
329).

The eighth and last stands as follows:--

"8. The developmental theory of Darwin is not needed to enable us
to understand the regular harmonious progress of the complete
series of organic forms from the simpler to the more perfect.

"The existence of general laws of Nature explains this harmony,
even if we assume that all beings have arisen separately and
independent of one another. Darwin forgets that inorganic nature,
in which there can be no thought of a genetic connexion of forms,
exhibits the same regular plan, the same harmony, as the organic
world; and that, to cite only one example, there is as much a
natural system of minerals as of plants and animals."

We do not feel quite sure that we seize Professor Koelliker's meaning
here, but he appears to suggest that the observation of the general
order and harmony which pervade inorganic nature, would lead us to
anticipate a similar order and harmony in the organic world. And this is
no doubt true, but it by no means follows that the particular order and
harmony observed among them should be that which we see. Surely the
stripes of dun horses, and the teeth of the foetal _Balaena_, are not
explained by the "existence of general laws of Nature." Mr. Darwin
endeavours to explain the exact order of organic nature which exists;
not the mere fact that there is some order.

And with regard to the existence of a natural system of minerals; the
obvious reply is that there may be a natural classification of any
objects--of stones on a sea-beach, or of works of art; a natural
classification being simply an assemblage of objects in groups, so as to
express their most important and fundamental resemblances and
differences. No doubt Mr. Darwin believes that those resemblances and
differences upon which our natural systems or classifications of animals
and plants are based, are resemblances and differences which have been
produced genetically, but we can discover no reason for supposing that
he