June IS, 191S Antagonism between Anions as Affecting Barley 



203 



TOXICITY OF THE SINGLE SALTS 



It should be stated first in connection with the experiments here 

 described that simultaneously with the series of pots containing salt 

 mixtures of various kinds, in addition to the control plants of every series, 

 several series of plants were also grown for the purpose of determining 

 the degree of toxicity of every one of the salts employed. In these 

 experiments the technique was exactly the same as that employed in 

 the antagonism series. All explanatory data with respect to this added 

 experiment which may be necessary to a comprehension of it are given 

 in Table I, which is presented in full below, despite its very unsatisfactory 

 nature as viewed from the standpoints above discussed. 



Table I. — Toxicity of sodium chlorid, sodium sulphate, and sodium carbonate for barley 



Some very interesting points may be gleaned by even a cursory 

 examination of Table I. These may be summarized as follows: 



(i) Very little, if any, toxicity is manifested by any of the salts in 

 the first crop. 



(2) Decided stimulation is evident in the lowest concentrations 

 employed of every one of the salts in the first crop. 



(3) No concentration of sodium carbonate employed gave anything 

 but strong stimulation in the first crop. 



(4) Stimulation was almost at a standstill in the sodium-sulphate 

 series at and above the 0.4 per cent concentration in the first crop. 



(5) Stimulation was at a standstill in the sodium-chlorid series at and 

 above the 0.15 per cent concentration in the first crop. 



