It is the
principle of the struggle for life between elementary species, followed
by the survival of the [703] fittest, the law of the selection of
species, which we have already laid stress upon more than once.
Our second consideration is also based upon the frequent repetition of
the several mutations. Obviously a common cause must prevail. The
faculty of producing _nanella_ or _lata_ remains the same through all
the years. This faculty must be one and the same for all the hundreds of
mutative productions of the same form. When and how did it originate? At
the outset it must have been produced in a latent condition, and even
yet it must be assumed to be continuously present in this state, and
only to become active at distant intervals. But it is manifest that the
original production of the characters of _Oenothera gigas_ was a
phenomenon of far greater importance than the subsequent accidental
transition of this quality into the active state. Hence the conclusion
that at the beginning of each series of analogous mutations there must
have been one greater and more intrinsic mutation, which opened the
possibility to all its successors. This was the origination of the new
character itself, and it is easily seen that this incipient change is to
be considered as the real one. All others are only its visible
expressions.
Pages:
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673