508 STUDIES IN GENERAL PHYSIOLOGY 
liquefaction of the pseudopodia upon the removal of the 
nucleus, and the inability of Infusorian fragments with- 
out a nucleus to form a new cuticle, correspond entirely 
with the assumption that the cell fragments without a 
nucleus are in a condition of decreased oxidative activity. 
I have expressed this view for several years in my lec- 
tures, and I have had it in mind to perform experiments 
on pieces of Infusoria without the nucleus under increased 
oxygen pressure. If my theory be correct, it should be 
possible to prolong the life of fragments of protoplasm 
freed from the nucleus by furnishing them a better supply 
of oxygen. But it seems to me that this experiment has 
already been made. For while Nussbaum, Gruber, and 
Verworn found that pieces of Infusoria without the nucleus 
go to pieces after two days, and only exceptionally live 
several days, all botanists who have made the same ex- 
periment on chlorophyll-bearing-cells (for example, Algze) 
have found that cell fragments without the nucleus remain 
alive five to six weeks.’ Assimilation took place in such 
pieces. It seems to me that the comparatively long dura- 
tion of life of fragments of Alge without a nucleus is of 
great importance in judging of the function of the cell 
nucleus. As is well known, oxygen is liberated in the 
assimilation of carbon dioxide. Pieces of Alge without a 
nucleus are therefore, in the light, under better conditions 
of oxygen supply than fragments of Infusoria without a 
nucleus, for the Infusorian contains no chlorophyll. 
It seems to me, therefore, that all the facts which are known 
thus far very naturally support the idea that the nucleus 
as the organ of oxidation of living matter; and that frag- 
ments of cells without a nucleus are not able to regenerate 
because their oxidative activity has fallen to too low a 
point. Such pieces die slowly from asphyxia. 
1 KuEss, Biologisches Centralblatt, Vol. VII (1888). 
Digitized by Microsoft® 
