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are the cases of Mutilaions. Secondly, modifications are caused in an animal body by Environments and lastly, changes in the bodily organs are often brought about by Kinetogenesis i.e. through use or disuse. As regards the cases of Mutilation, it is well known that the effects of simple and single mutilations are not inherited. It was at one time thought that mutilations which have a persisting impress on the organism modify it in such a way that their effects would affect the succeeding generations. Darwin thought that the remarkably small prepuce in the Mahomedans of Celebes afforded an instance of the heritability of long continued mutilations. Without entering into further discussions, it may suffice to state here the net result of scientific observations, which is that even the effect of long-continued mutilations are not inherited. The experiments of Naegeli and De Candolle on plants show that the inheritance of the effects of changed conditions is quite uncertain. Lastly, observation and experiments in a similar manner have failed to prove conclusively that effects of the use or disuse of an organ are inherited. Closer estimate of evidence goes to show that in a great majority of cases conclusions about the inheritance of acquired characters are hasty and unfounded. The Scottish Highlanders, for instance, have many individuals among them who are of any ordinary human height while the Spaniards who are dolicho-cephalic people have many who are extremely round-headed. In very many cases, again, likeness of the son to his parents or grandparents need not necessarily mean that the former has actually inherited the acquired features of the latter; the likeness may be explained by the supposition that similar epigenetic influences have produced in the offspring results similar to those produced
in the ancestors.
Matter
DIFFICULTIES OF THE DOCTRINE
Cases, of course, there are where the peculiarities in the features common to the offspring and the ancestors cannot be satisfactorily accounted for by the reference to the epigenetic
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