taken as an indication that the nucleus olnyed an important 

 role in oxidations, but the presence of this iron is ooen 

 to doubt. 3pitzer's cata-lase may have been derived from the 

 cytoplasm. 



The chemical evidence for the oxidation theory is very 

 slight, and the physiological evidence is equally so. The 

 assumption that the organ which is furth^/est removed from 

 the supply of oxygen is the organ of oxidation is not logical 

 in the first place. "It should be born in mind that oxy,r;en, 

 in order to reach the nucleus, must penetrate a layer of 

 cytoplasm containing reducing substances." (R. Lillie, 1^11, 

 p 722). Moreover, as was sho\m in the above experiments, the 

 non-nucleated cell may exhibit perfectly normal movements, 

 oince the energy for movement in aerobic organisms is deriv- 

 ed from the oxidation of organic matter, it is unlikely that 

 oxidations have become depressed. But if there is a depression 

 of oxidations we should certainly expect f cf Loeb, I'^'^S) 

 to find some improvement in the cell when we increase its 

 supply of oxygen. On the contrary, as has been shown, the 

 cell becomes spherical and dies in a few hours. Also the 

 susceptibility to lack of oxygen, the susceptibility to 

 cyanide, and the susceptibility to high and low temperature 

 all indicate that respiration and rate of metabolism are 

 quite a'3 rapid in the enucleated cell as in the normal cell. 



Recently, however, experiments have been reported which 



'-35) 



