4 THE BOTANICAL MAGAZINE. [Vol. xxviii. No. 325. 



as in the preceding experiment. The plants had developed very 

 well with remarkable difference in growth. The plants were 

 measured on March 24th with the following result which coin- 

 cides with that of the preceding experiment. 



Result. 



The injurious effect of the metallic ions upon the growth of 

 rice seedlings is perfectly counteracted only by the presence of 

 calcium ion while strontium ion can exert an influence only 

 slightly retarding the toxicity of the metallic ions. Barium ion 

 not only has no beneficial action, but a depressing effect is 

 observed. Consequently, it is concluded that barium and 

 strontium could not replace the antagonistic action of calcium. 



Chemical Laboratory, College of Agriculture, 

 ToHOKU Imperial University, Sapporo, Japan. 

 July, 1913. 



