REGENERATION OF PROTOPLASMIO FRAGMENTS 509 
The question as to the significance of the nucleus for 
development and heredity enters into a new light if these 
ideas are correct. Nor can it longer be held that the living 
organism is merely a combination of individual cells. “By 
cellular structure we understand the fact that there must be 
a definite maximal distance, variable, however, for different 
forms and tissues, between the elements of the protoplasm 
and the nearest nucleus.”’ We can now understand the 
reason for this. If the distance becomes too great, the 
particular protoplasmic element goes to pieces from as- 
phyxia. That besides this an interchange of other sub- 
stances occurs between the protoplasm and the nucleus I 
will, of course, not deny; it is possible or probable that the 
significance of the cell nucleus is not exhausted by its oxida- 
tive activity. It is also scarcely necessary to point out par- 
ticularly that I do not believe that without’ the nucleus all 
processes of oxidation cease in the protoplasm; it rather 
seems from all the facts at hand that it is only markedly 
decreased. 
1 Logs, Pfliigers Archiv, Vol. LXIX (1897). 
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