280 Theories Treating of Inheritance 



between each chemical and the corresponding morpho- 

 logical stage of development; for this morphological 

 character of different chemical reactions has not so far 

 been observed in any phenomena of the inorganic world, 

 since it has absolutely no analogue in the process of 

 crystallization which is a property of the molecular struc- 

 ture of already formed, stable substances, that is of 

 substances in perfect statico-chemical equilibrium. But 

 we may mention the fact and after all which has been 

 said above no further proof of it is required that the 

 fundamental phenomena, such as the regeneration of 

 amputated organs, the occasional reappearance especially 

 in crosses of atavistic characters long since disappeared, 

 and especially the ontogenetic repetition of phylogeny 

 and the inheritance of acquired characters, not only find 

 no explanation in all these hypotheses of chemical 

 development but are on the contrary absolutely irrecon- 

 cilable with them. 



Darwin, Gait on, DeVries, IVeismann 



It would be useless for our purpose to tarry especially 

 over any one of these four theories, the underlying idea 

 of all being the same identical conception of preformistic 

 germs. The progressive elaboration of this idea which 

 has proceeded gradually from the first to the last of these 

 theories presents however the following noteworthy 

 phenomenon. Preformistic germs, which were devised 

 by Darwin, one could well say, chiefly for the purpose of 

 accounting for the inheritance of acquired characters, 

 were then deprived by Galton in great part but not com- 

 pletely of this property, and finally with DeVries, and 

 still more with Weismann became themselves the greatest 

 difficulty for accepting that inheritance. 



