I2O Phenomena Refuting Simple Epigenesis 



follows therefore that each fact or each argument which 

 speaks in favor of nuclear somatization, is at the same 

 time a proof against epigenesis. And we saw precisely 

 in the preceding chapter, that there is a whole series of 

 facts and arguments, which it would be useless to repeat 

 here, but which compel us to admit this nuclear 

 somatization as an incontrovertible fact. 



The preformationists can finally object to epigenesis 

 and not unreasonably, that by its "attainment of equilib- 

 rium," it does not explain the termination of ontogeny 

 as well as preformation does. For why should the 

 reciprocal actions of all parts, on which development 

 depended up to that time, suddenly cease to effect any 

 further change when once the adult stage is reached? 

 Because it is only then, reply the epigenesists, that the 

 dynamic equilibrium is attained. But if the successive 

 ontogenetic forms repeat the phylogenetic, how comes 

 it that the dynamic equilibrium which once existed in 

 each of these latter does not remain existent in any of 

 the former? And if the absence of equilibrium at all 

 these stages is due to some alteration of the formative 

 living substance, how then could this new substance pass 

 again during a long series of stages through the same 

 phylogenetic ancestral forms? The preformists, on the 

 contrary, have no trouble in explaining the arrest of 

 development since according to their theory it would 

 follow only at the moment when there would be present 

 in each cell only a single kind of preformistic or 

 determinant germs. 



Having thus made a rapid review of the principal 

 objections which compel us to reject epigenesis, we can 

 pass on to an equally brief consideration of a number 



