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result of the theory is the impossibility of the transmission of
acquired characters； since the molecular structure of the germ…plasm
is already determined within the embryo； and Weismann holds that
there are no facts which really prove that acquired characters can
be inherited； although their inheritance has； by most writers； been
considered so probable as hardly to stand in need of direct proof。
〃We have already seen in the earlier part of this chapter that many
instances of change； imputed to the inheritance of acquired
variations； are really cases of selection。〃
And the rest of the remarks tend to convey the impression that Mr。
Wallace adopts Professor Weismann's view； but； curiously enough；
though I have gone through Mr。 Wallace's book with a special view to
this particular point； I have not been able to find him definitely
committing himself either to the assertion that acquired
modifications never are inherited； or that they sometimes are so。
It is abundantly laid down that Mr。 Darwin laid too much stress on
use and disuse； and a residuary impression is left that Mr。 Wallace
is endorsing Professor Weismann's view； but I have found it
impossible to collect anything that enables me to define his
position confidently in this respect。
This is natural enough； for Mr。 Wallace has entitled his book
〃Darwinism；〃 and a work denying that use and disuse produced any
effect could not conceivably be called Darwinism。 Mr。 Herbert
Spencer has recently collected many passages from 〃The Origin of
Species〃 and from 〃Animals and Plants under Domestication；〃 ｛26｝
which show how largely； after all； use and disuse entered into Mr。
Darwin's system； and we know that in his later years he attached
still more importance to them。 It was out of the question；
therefore； that Mr。 Wallace should categorically deny that their
effects were inheritable。 On the other hand； the temptation to
adopt Professor Weismann's view must have been overwhelming to one
who had been already inclined to minimise the effects of use and
disuse。 On the whole； one does not see what Mr。 Wallace could do；
other than what he has doneunless； of course； he changed his
title； or had been no longer Mr。 Wallace。
Besides； thanks to the works of Mr。 Spencer； Professor Mivart；
Professor Semper； and very many others； there has for some time been
a growing perception that the Darwinism of Charles Darwin was
doomed。 Use and disuse must either do even more than is officially
recognised in Mr。 Darwin's later concessions； or they must do a
great deal less。 If they can do as much as Mr。 Darwin himself said
they did； why should they not do more？ Why stop where Mr。 Darwin
did？ And again； where in the name of all that is reasonable did he
really stop？ He drew no line； and on what principle can we say that
so much is possible as effect of use and disuse； but so much more
impossible？ If； as Mr。 Darwin contended； disuse can so far reduce
an organ as to render it rudimentary； and in many cases get rid of
it altogether； why cannot use create as much as disuse can destroy；
provided it has anything； no matter how low in structure； to begin
with？ Let us know where we stand。 If it is admitted that use and
disuse can do a good deal； what does a good deal mean？ And what is
the proportion between the shares attributable to use and disuse and
to natural selection respectively？ If we cannot be told with
absolute precision； let us at any rate have something more definite
than the statement that natural selection is 〃the most important
means of modification。〃
Mr。 Darwin gave us no help in this respect； and worse than this； he
contradicted himself so flatly as to show that he had very little
definite idea upon the subject at all。 Thus in respect to the
winglessness of the Madeira beetles he wrote：…
〃In some cases we might easily put down to disuse modifications of
structure； which are wholly or mainly due to natural selection。 Mr。
Wollaston has discovered the remarkable fact that 200 beetles； out
of the 550 species （but more are now known） inhabiting Madeira； are
so far deficient in wings that they cannot fly； and that of the 29
endemic genera no less than 23 have all their species in this
condition！ Several facts；namely； that beetles in many parts of
the world are frequently blown out to sea and perish； that the
beetles in Madeira； as observed by Mr。 Wollaston； lie much concealed
until the wind lulls and the sun shines； that the proportion of
wingless beetles is larger on the exposed Desertas than in Madeira
itself； and especially the extraordinary fact； so strongly insisted
on by Mr。 Wollaston； that certain large groups of beetles； elsewhere
excessively numerous； which absolutely require the use of their
wings are here almost entirely absent；these several considerations
make me believe that the wingless condition of so many Madeira
beetles is mainly due to the action of natural selection； COMBINED
PROBABLY WITH DISUSE ＇italics mine＇。 For during many successive
generations each individual beetle which flew least； either from its
wings having been ever so little less perfectly developed or from
indolent habit； will have had the best chance of surviving； from not
being blown out to sea； and； on the other hand； those beetles which
most readily took to flight would oftenest have been blown to sea；
and thus destroyed。〃 ｛27｝
We should like to know； first； somewhere about how much disuse was
able to do after all； and moreover why； if it can do anything at
all； it should not be able to do all。 Mr。 Darwin says： 〃Any change
in structure and function which can be effected by small stages is
within the power of natural selection。〃 〃And why not；〃 we ask；
〃within the power of use and disuse？〃 Moreover； on a later page we
find Mr。 Darwin saying：…
〃IT APPEARS PROBABLE THAT DISUSE HAS BEEN THE MAIN AGENT IN
RENDERING ORGANS RUDIMENTARY ＇italics mine＇。 It would at first lead
by slow steps to the more and more complete reduction of a part；
until at last it has become rudimentaryas in the case of the eyes
of animals inhabiting dark caverns； and of the wings of birds
inhabiting oceanic islands； which have seldom been forced by beasts
of prey to take flight； and have ultimately lost the power of
flying。 Again； an organ； useful under certain conditions； might
become injurious under others； AS WITH THE WINGS OF BEETLES LIVING
ON SMALL AND EXPOSED ISLANDS； and in this case natural selection
will have aided in reducing the organ； until it was rendered
harmless and rudimentary ＇italics mine＇。〃 ｛28｝
So that just as an undefined amount of use and disuse was introduced
on the earlier page to supplement the effects of natural selection
in respect of the wings of beetles on small and exposed islands； we
have here an undefined amount of natural selection introduced to
supplement the effects of use and disuse in respect of the identical
phenomena。 In the one passage we find that natural selection has
been the main agent in reducing the wings； though use and disuse
have had an appreciable share in the result； in the other； it is use
and disuse that have been the main agents； though an appreciable
share in the result must be ascribed to natural selection。
Besides； who has seen the uncles and aunts going away with the
uniformity that is necessary for Mr。 Darwin's contention？ We know
that birds and insects do often get blown out to sea and perish； but
in order to establish Mr。 Darwin's position we want the evidence of
those who watched the reduction of the wings during the many
generations in the course of which it was being effected； and who
can testify that all； or the overwhelming majority； of the beetles
born with fairly well…developed wings got blown out to sea； while
those alone survived whose wings were congenitally degenerate。 Who
saw them go； or can point to analogous cases so conclusive as to
compel assent from any equitable thinker？
Darwinians of the stamp of Mr。 Thiselton Dyer； Professor Ray
Lankester； or Mr。 Romanes； insist on their pound of flesh in the
matter of irrefragable demonstration。 They complain of us for not
bringing forward some one who has been able to detect the movement
of the hour…hand of a watch during a second of time； and when we
fail to do so； declare triumphantly that we have no evidence that
there is any connection between the beating of a second and the
movement of the hour…hand。 When we say that rain comes from the
condensation of moisture in the atmosphere； they demand of us a
rain…drop from moisture not yet condensed。 If they stickle for
proof and cavil on the ninth part of a hair； as they do when we
bring forward what we deem excellent instances of the transmission
of an acquired characteristic； why may not we； too； demand at any
rate some evidence that the unmodified beetles actually did always；
or nearly always； get blown out to sea； during the reduction above
referred to； and that it is to this fact； and not to the masterly
inactivity of their fathers and mothers； that the Madeira beetles
owe their winglessness？ If we began stickling for proof in this
way； our opponents would not be long in letting us know that
absolute pro