DIFFERENCES IN ANAEROB. FUNCTIONS 271 



bers, Beck and Green, 1933; Ghambers, 1933; Clark, 

 1934. 



As was pointed out by Chambers, Cohen and Pollack 

 (1932) some of the discrepancies in the literature can 

 probably be explained by the fact that not enough at- 

 tention was paid to the '^ capacity" factor, i.e., to the 

 total reducing- power of the cells. Occasionally the 

 amounts of dye injected were so large as to overtax this 

 reducing power. 



It should furthermore be kept in mind that all the 

 measurements recorded deal with the ''overall" poten- 

 tial of the cells. Jahn (1941) recently remarked that 

 ''the colloidal nature of protoplasm makes possible the 

 existence of different Eh values in different phases of 

 the substance, and the differential adsorption of oxidized 

 and reduced material at interfaces may produce a poten- 

 tial dift'erent from that in any of the phases." This 

 conception may, in the future, if precise data can be ob- 

 tained, lead to the discovery of important mechanisms for 

 the adaptation or non-adaptation to anaerobic life in va- 

 rious organisms. 



A final observation, that possibly is related to the in- 

 ternal oxidation-reduction potential, may be mentioned 

 here. Nassonov (1932) found that the macronucleus of 

 typically aerobic protozoa {Paramaecium, Stent or and 

 others) normally does not stain with vital dyes, unless 

 the organisms are damaged. The macronuclei of proto- 

 zoa living in oxygen-poor or oxygen-free surroundings 

 (rumen ciliates, Balantidkim and others) stain rapidly 

 in perfectly normal specimens. 



