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18

been at work.

At one time Brown-S
Z
equard's experiments on guinea-pigs were thought to afford conclusive
exclusive
evidence in favour of the inheritance of acquired characters. But these experiments have never
now
been verified and are now
more
generally discredited by Zoologist Romance in his Darwin and after Darwin (Vol.II.p.ll4) gives an account of some investigations which he carried on along the same lines. on the whole he found himself unable to furnish any approach to a full corroboration of Brown-S
Z
equard's results. It is difficult to believe that (illegible text)
^
are ever inherited
now unlimited
, for though the Jews have carried on the rite
rule
of circumcision for centuries no effect has been observed on succeeding generations. But as has been pointed out by Herbert Spencer (appendix Principles of Biology.p.631.) the inheritance or non-inheritance of (illegible text)
^
is beside the question. The fact that no evidence for such exist does not prejudice the question of the inheritability of characters acquired through functional changes.

Weismannists have never
now
been able to meet satisfactorily the difficulty which arises in explaining the co-adaptation of cooperative parts unless the Lamarckian factors are called in. This difficulty has been well explained and exemplified by Herbert Spencer and by Romanes. As Romanes observes "it belongs to the essence of co-ordination that each of the co-ordinated parts should be destitute of adaptive value per.se.: the adaption only begins to arise if all the parts in question occur associated together in the same individual from the very first." Natural selection alone is not sufficient to account