Oct, Mis.] x. MI YAKE.— INFLUENCE OF THE SALTS ETC. 195 



salts, what has been observed not only witfc algae, but also 

 with young plants of barley and maize which were deprived of 

 their endsperm. 



Hansteen V) has recently investigated the antagonism 

 between cations upon the growth of wheat seedlings and 

 shown that the pure solutions of potassium, sodium and 

 magnesium salts are more or less injurious according to their 

 concentrations. But in combination with calcium salts, their 

 injurious effect on the growth of leaves, roots and root-hairs is 

 greatly decreased and especially calcium has a strong antagon- 

 istic action which served as protection of root growth. 



Toxic and antagonistic effects of salts as related to am- 

 m.onification by Bacillus suhtilis were also investigated by 

 Lipman 2) and the following conclusions were reported : 1. Each 

 of the four chlorides {CaCl 2 , MgCl 2 , KC1, NaCl.) is toxic for 

 Bacillus subtilis, in the order given, the first being the most 

 toxic and the fourth the least. This is quite different from the 

 results with higher plants, where magnesium is the most toxic 

 and calcium the least. 2. A marked antagonism exists between 

 calcium and potassium, magnesium and sodium, potassium and 

 sodium. 3. No antagonism exists between magnesium and 

 calcium but the toxic effect of each is increased by combination 

 with the other. This is just the opposite of what has hitherto 

 been found for plants. 



As above stated, it is clear that the toxicity of a single 

 salt solution is neutralized by the presence of a second salt, 

 especially calcium salts. This subject is most important and 

 very interesting. It should be tested by examination of the 

 influence of the salts common in alkali soils upon the growth . 

 of rice plants. We have therefore selected chloride of sodium, 

 magnesium and calcium, and sulphate of sodium and magne- 

 sium as the salts to be tested and examined the respective 

 antagonisms between these salts in combination. 



1) Nyt. Mag. Naturvidensk., Bd. 47, pp. 181-192 (1909); ref. Exp. Sta. Bee, U. S. 

 Dept. of Agriculture, Vol. 23, p. 28 (1910). 



2) Bot. Gaz., Vol. 48, pp. 105-124 (1909). 



