374 RETROSPECT 



protoplasm cannot be spontaneous!}" generated from unformed 

 solutions because, complicated and delicately inter-adjusted as they 

 are, they can only actualize in contact with already existing structures. 

 Hence the supreme axiom of cytology, namely, that all cells derive 

 from their like, applies equally, though in a wider sense, to invisible, 

 submicroscopic cytogenesis : 



STRUCTURA OMNIS E STRUCTURA 



I 



