February 2, 1917] 



SCIENCE 



101 



We thus arrive at an explanation of 

 antagonism. The theory* attempts to ac 

 count for the following facts. 



1. Why both NaCl and CaCL are toxic. 



tion of certain fundamental problems of 

 biology. 



Reference has been made to the sugges- 

 tion that calcium antagonizes sodium by 



TABLE I 



Observed and Calculated Values of Sesistance of Laminaria in Mixtures of NaCl and CaCk 



The measurements were made at 15° C. or corrected to this figure, 

 average obtained from 6 series of experiments. 



All the mixtures had the same conductivity as sea water. 



Each experimental figure is the 



2. Why when mixed in the proper pro- 

 portions their toxicity is greatly dimin- 

 ished (antagonistic action). 



3. Why they have opposite eifects on 

 permeability. 



4. Why the decrease of permeability pro- 

 duced by CaCl, must be followed by an in- 

 crease when the exposure is sufficiently pro- 

 longed. 



5. Why all toxicity disappears in sea 

 water. This is accounted for by supposing 

 that in sea water A is formed as fast as it 

 decomposes. 



The theory gives a quantitative explana- 

 tion of the toxicity of all the mixtures and 

 enables us to predict the resistance (and 

 permeability) in any mixture at any mo- 

 ment during exposure. 



It likewise emphasizes the fact that life 

 processes consist largely of consecutive re- 

 actions and that analysis of the dynamics of 

 such reactions is indispensable for the solu- 



i Of. Tree. Am. Phil. Sac, 55 : 533, 1916. 



preventing it from entering the cell. This 

 explanation encounters a difficulty in the 

 fact that even in a balanced solution the 

 salts penetrate the cell. This difficulty dis- 

 appears if we adopt the point of view which 

 has just been presented, for it is evident 

 that on this basis we do not regard antag- 

 onism as due to prevention of penetration. 

 Nor is there any reason to suppose that the 

 penetration of salts will have an unfavor- 

 able effect provided that as they penetrate 

 into the cell the balance between them is 

 preserved. 



There is another aspect of the subject 

 which is of considerable interest. It is usu- 

 ally found that when antagonistic sub- 

 stances are mixed in various combinations 

 there is one proportion which is more favor- 

 able than others. If we increase the con- 

 centration of one constituent it is neces- 

 sary to increase the concentrations of the 

 others in like proportion in order to pre- 

 serve the optimum condition. This law of 



