day. On the view of each organic being and
each separate organ having been specially created, how utterly inexplicable
it is that parts, like the teeth in the embryonic calf or like the
shrivelled wings under the soldered wing-covers of some beetles, should
thus so frequently bear the plain stamp of inutility! Nature may be said to
have taken pains to reveal, by rudimentary organs and by homologous
structures, her scheme of modification, which it seems that we wilfully
will not understand.

I have now recapitulated the chief facts and considerations which have
thoroughly convinced me that species have been modified, during a long
course of descent, by the preservation or the natural selection of many
successive slight favourable variations. I cannot believe that a false
theory would explain, as it seems to me that the theory of natural
selection does explain, {481} the several large classes of facts above
specified. I see no good reason why the views given in this volume should
shock the religious feelings of any one. A celebrated author and divine has
written to me that "he has gradually learnt to see that it is just as noble
a conception of the Deity to believe that He created a few original forms
capable of self-development into other and needful forms, as to believe
that He required a fresh act of creation to supply the voids caused by the
action of His laws."

Why, it may be asked, have all the most eminent living naturalists and
geologists rejected this view of the mutability of species? It cannot be
asserted that organic beings in a state of nature are subject to no
variation; it cannot be proved that the amount of variation in the course
of long ages is a limited quantity; no clear distinction has been, or can
be, drawn between species and well-marked varieties. It cannot be
maintained that species when intercrossed are invariably sterile, and
varieties invariably fertile; or that sterility is a special endowment and
sign of creation. The belief that species were immutable productions was
almost unavoidable as long as the history of the world was thought to be of
short duration; and now that we have acquired some idea of the lapse of
time, we are too apt to assume, without proof, that the geological record
is so perfect that it would have afforded us plain evidence of the mutation
of species, if they had undergone mutation.

But the chief cause of our natural unwillingness to admit that one species
has giv