398 PROVISIONAL HYPOTHESIS Chap. xxVtf. 



in any way improbable, for, though a vast number of active and 

 long-dormant gemmnles are diffused and nourished in each livii 

 creature, yet there must be some limit to their number ; and 

 appears natural that gemmules derived from an enfeebled and use- 

 less rudiment would be more liable to perish than those derived 

 from other parts which are still in full functional activity. 



"With respect to mutilations, it is certain that a part may 

 be removed or injured during many generations, and no in- 

 herited result follow ; and this is an apparent objection to the 

 hypothesis which will occur to every one. But, in the first 

 place, a being can hardly be intentionally mutilated during its 

 early stages of growth whilst in the womb or egg ; and such 

 mutilations, when naturally caused, would appear like con- 

 genital deficiencies, which are occasionally inherited. In the 

 second place, according to our hypothesis, gemmules multiply 

 by self-division and are transmitted from generation to gene- 

 ration ; so that during a long period they would be present and 



to reproduce a part which was repeatedly amputated. 

 Nevertheless it appears, from the facts given in the twelfth 

 chapter, that in some rare cases mutilations have been inhe- 

 rited, but in most of these the mutilated surface became diseased. 

 In this case it may be conjectured that the gemmules of the lost 

 part were gradually all attracted by the partially diseased surface, 

 and thus perished. Although this would occur in the injured 

 individual alone, and therefore in only one parent, yet this might 

 suffice for the inheritance of a mutilation, on the same principle 

 that a hornless animal of either sex, when crossed with a perfect 

 animal of the opposite sex, often transmits its deficiency. 



The last subject that need here be discussed, namely Eever- 

 sion, rests on the principle that transmission and development, 

 though generally acting in conjunction, are distinct powers ; and 

 the transmission of gemmules and their subsequent development 

 show us how the existence of these two distinct powers is 

 possible. We plainly see this distinction in the many cases in 

 which a grandfather transmits to his grandson, through his 

 daughter, characters which she does not, or cannot, possess. 

 Why the development of certain characters, not necessarily m 

 any way connected with the reproductive organs, should be con- 

 fined to one sex alone — that is, why certain cells in one sex 







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