116 Theory of the Germ-Plasm 



published about ten years ago,^^ Vochting brought to- 

 gether the facts known at that time and the results of his 

 own rich experiments. At the end of the first volume he 

 discusses the pending question in detail. The experiments 

 teach directly (p. 251), that ''in every fragment, be it 

 ever so small, of the organs of the plant-body, rest the 

 elements from which, by isolating the fragment, under 

 proper external conditions, the whole body can be built 

 up." Of course, this is true only if the fragment contains a 

 number of meristematic cells. On this basis the question is 

 discussed, "Whether there is a sufficient support for ex- 

 tending our proposition over any given complex of living 

 vegetative cells." This discussion again leads to the as- 

 sumption that every morphological form of tissue is po- 

 tentially in a condition to produce meristematic cells, and 

 therefore to reproduce the entire organism. But since 

 experiments involving the isolation of very small portions 

 of tissues encounter unsurmountable difficulties, and since, 

 on the other hand, the power of reproduction as an adap- 

 tation may very likely have been lost in many tissues, 

 there is, as a matter of course, no "strict proof attempted, 

 and it is simply claimed that this very plausible assump- 

 tion is probably correct. "^^ 



This assumption, however, in the now current lan- 

 guage, has no other meaning than that all, or at least the 

 greatest number of the cells of the plant-body contain all 

 the hereditary characters of the species in a latent condi- 

 tion. And this same assumption I have sought to estab- 

 lish, as far as possible, empirically, through a detailed 

 description of cell-pedigrees available through the most 

 recent investigations on the phenomena of regeneration. 



27Vol. I, Bonn, 1878 ; Vol. II, Bonn, 1884. 

 28Loc. cit. pp. 251-253. 



