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merely passive victim of external conditions of selection,
we have here another reason for believing that protective
colouring does not present the most favourable illustration
of the action of that supposed law of nature.
Before leaving this subject, we may further enquire
whether a certain sphere of nature presents a favourable
illustration of the action of a given law in proportion to the
amount of influence which that law is supposed to exercise
in the production of a given phenomenon. One would
be tempted to say at the outset that the action of Natural
Selection will be in inverse ratio to the amount of assist
ance which is rendered by other factors, that it will be
most favourably observed where it has most to do. It
would seem absurd to say that it is most effective when
it has least to do. We should surely be disappointed if
we had gone to see the popular actor of the season in
the character of Hamlet, and if we found that he had
chosen to be cast for the part of Fortinbras, who walks
across the stage towards the end of the fourth act and
comes to clear it up at the end of the fifth. This illus
tration may also serve to remind us that the character
which plays an insignificant part in a drama is apt to be
left out altogether, as in the play of Hamlet, when the
curtain falls upon the stage strewn with dead. And is it
not possible that if Natural Selection is required to do so
little it can be dispensed with altogether ? There are cases
in which close resemblance is brought about without
Natural Selection, and if this case of mimicry—i.e., close
resemblance—is nearly accomplished apart from Natural
Selection, what need is there for it at all ?
“ If, then, we must admit that the first beginning of change takes
place without the operation of this principle, why should we claim for
it the main, almost the exclusive, agency in the changes which follow'?
Some other principle, at present unknown to us, originates these
variations ; what right have w ; e to say that this principle, whatever it
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