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the last paragraph of the book all this was changed, and the
variations were ascribed to the conditions of existence, and to use
and disuse, but a concluding paragraph cannot be allowed to override
a whole book throughout which the variations have been kept to hand
as accidental. Mr. Romanes is perfectly correct when he says {232a}
that "natural selection" (meaning the Charles-Darwinian natural
selection) "trusts to the chapter of accidents in the matter of
variation" this is all that Mr. Darwin can tell us; whether they
come from directly transforming agents or no he neither knows nor
says. Those who accept Lamarck will know that the agencies are not,
as a rule, directly transforming, but the followers of Mr. Darwin
cannot.
"But showing themselves," continues Professor Ray Lankester, "at
each new act of reproduction, as part of the phenomena of heredity
such minute 'sports' or 'variations' are due to constitutional
disturbance" (No doubt. The difference, however, between Mr. Darwin
and Lamarck consists in the fact that Lamarck believes he knows what
it is that so disturbs the constitution as generally to induce
variation, whereas Mr. Darwin says he does not know), "and appear
not in individuals subjected to new conditions" (What organism can
pass through life without being subjected to more or less new
conditions? What life is ever the exact fac-simile of another? And
in a matter of such extreme delicacy as the adjustment of psychical
and physical relations, who can say how small a disturbance of
established equilibrium may not involve how great a rearrangement?),
"but in the offspring of all, though more freely in the offspring of
those subjected to special causes of constitutional disturbance.
Mr. Darwin has further proved that these slight variations can be
transmitted and intensified by selective breeding."
Mr. Darwin did, indeed, follow Buffon and Lamarck in at once turning
to animals and plants under domestication in order to bring the
plasticity of organic forms more easily home to his readers, but the
fact that variations can be transmitted and intensified by selective
breeding had been so well established and was so widely known long
before Mr. Darwin was born, that he can no more be said to have
proved it than Newton can be said to have proved the revolution of
the earth on its own axis. Every breeder throughout the world had
known it for centuries. I believe even Virgil knew it.
"They have," continues Professor Ray Lankester, "in reference to
breeding, a remarkably tenacious, persistent character, as might be
expected from their origin in connection with the reproductive
process."
The variations do not normally "originate in connection with the
reproductive process," though it is during this process that they
receive organic expression. They originate mainly, so far as
anything originates anywhere, in the life of the parent or parents.
Without going so far as to say that no variation can arise in
connection with the reproductive system--for, doubtless, striking
and successful sports do occasionally so arise--it is more probable
that the majority originate earlier. Professor Ray Lankester
proceeds:-
"On the other hand, mutilations and other effects of directly
transforming agents are rarely, if ever, transmitted." Professor
Ray Lankester ought to know the facts better than to say that the
effects of mutilation are rarely, if ever, transmitted. The rule
is, that they will not be transmitted unless they have been followed
by disease, but that where disease has supervened they not
uncommonly descend to offspring. {234a} I know Brown-Sequard
considered it to be the morbid state of the nervous system
consequent upon the mutilation that is transmitted, rather than the
immediate effects of the mutilation, but this distinction is
somewhat finely drawn.
When Professor Ray Lankester talks about the "other effects of
directly transforming agents" being rarely transmitted, he should
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