ssible.
Larvae are active embryos, which have become specially modified in
relation to their habits of life, through the principle of modifications
being inherited at corresponding ages. On this same principle--and
bearing in mind, that when organs are reduced in size, either from
disuse or selection, it will generally be at that period of life when
the being has to provide for its own wants, and bearing in mind how
strong is the principle of inheritance--the occurrence of rudimentary
organs and their final abortion, present to us no inexplicable
difficulties; on the contrary, their presence might have been even
anticipated. The importance of embryological characters and of
rudimentary organs in classification is intelligible, on the view that
an arrangement is only so far natural as it is genealogical.

Finally, the several classes of facts which have been considered in
this chapter, seem to me to proclaim so plainly, that the innumerable
species, genera, and families of organic beings, with which this world
is peopled, have all descended, each within its own class or group, from
common parents, and have all been modified in the course of descent,
that I should without hesitation adopt this view, even if it were
unsupported by other facts or arguments.

14. RECAPITULATION AND CONCLUSION.

Recapitulation of the difficulties on the theory of Natural Selection.
Recapitulation of the general and special circumstances in its favour.
Causes of the general belief in the immutability of species. How far the
theory of natural selection may be extended. Effects of its adoption on
the study of Natural history. Concluding remarks.

As this whole volume is one long argument, it may be convenient to the
reader to have the leading facts and inferences briefly recapitulated.

That many and grave objections may be advanced against the theory of
descent with modification through natural selection, I do not deny. I
have endeavoured to give to them their full force. Nothing at first can
appear more difficult to believe than that the more complex organs and
instincts should have been perfected, not by means superior to, though
analogous with, human reason, but by the accumulation of innumerable
slight variations, each good for the individual possessor. Nevertheless,
this difficulty, though appearing to our imagination insuperably great,
cannot be considered real if we admit the following propositions,
namely,--that gradations in