Antitoxic Action of Certain Bases 125 



with the root grou'th of those placed m pure solutions of .12 mol. NaCl and 

 .12 mol. NH4CI, respectively. The increase in growth of the roots in the 

 mixed solutions over that in the pure cultures is attributed wholly to the 

 antagonistic action of the bases sodium and ammonium, whereas it is cer- 

 tainly due in part merely to the reduction of the concentration of each salt 

 from .12 to .06 mol.; yet antagonism is obvious. 



In view of all the considerations stated, a reinvestigation of antitoxic 

 action ^dth reference to certain seed plants has seemed especially necessary; 

 likewise, it is important to extend the work so as to include certain bases 

 that have been less studied. 



scope of the investigation 



The "^Titer has concluded experiments with various nutrient and non- 

 nutrient mineral bases, using Canada field peas and wheat as indicators. 

 He has made a comparative study of the growth of tops and roots in solu- 

 tions of the different salts containing single bases, in concentrations varying 

 from those that are non-toxic to those that practically prohibit growth, and 

 in solutions containing two bases at various concentrations including those 

 strengths that are toxic when employed alone. An effort was also made 

 to determine the minimum of one base that would antidote a given toxic 

 amount of another base, but much remains to be done in this direction. 



The experiments reported in the present bulletin include studies of the 

 bases Ca, K, Na, NH3, Mg, Sr, and Ba. In studying the relations of calcium 

 and strontium ions they were combined as Ca(N03)2 + Sr(N03)2 and 

 CaCl2 + SrCl2. The experiments with calcium and magnesium consisted 

 of CaCl2 + MgCl2 and CaCU + ]MgS04. In all other cases the chlorids 

 only were used. Data which are to be presented show that calcium anti- 

 dotes each of the bases mentioned above, and that definite mutual antag- 

 onism exists in the following combinations: 



Mg and Sr Na and NH3 



Mg and Ba Na and Sr 



Na and K K and Sr 

 K and Ba 



Other cases in which mutual antagonism may possibly occur are dis- 

 cussed later. 



