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18 been at work.

At one time Brown-equard's experiments on guinea-pigs were thought to afford evidence in favour of the inheritance of acquired characters. But these experiments have been verified and are  generally discredited by Zoologist Romance in his  (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-equard's results. It is difficult to believe that are, for though the Jews have carried on the  of circumcision for centuries no effect has been observed on succeeding generations. But as has been pointed out by Herbert Spencer (appendix p.631.) the inheritance or non-inheritance of 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 been able to meet satisfactorily the difficulty which arises in explaining the  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 : the adaption only begins to arise if all the parts in question occur associated together in the same individual Natural selection alone is not sufficient to account