236 



BOTANICAL GAZETTE 



[apkil 



concluded which of the three is the most toxic. Comparison of the 

 individuals of the series leads to nothing decisive. The next tabic 

 shows that fluctuating differences occur. 



TABLE III 



POTASSIUM 



m 



Control 



Water 

 8..... 



4 

 2 



I 



0.09 



o.io 



0.09 

 0.09 

 0.09 



Enzvme 



Increase 



0.23 

 o. 20 

 0.18 

 0.16 

 0.12 



o. 14 



O.IO 



0.09 

 0.07 



0.03 



LITHIUM 



Enzyme 0.05 per cent. Incubation 5 hours at 45 C. 



There seems to be some indication that lithium is more toxic than 

 sodium or potassium, but the difference is too insignificant for a conclu- 

 sion. In all the \dals the unboiled solutions were free from sediment. 

 Since the salt solutions themselves are neutral in all the concen- 



tried 



^/4o KOH instead of the m/ 



with 



CTeater 



D 



The 



rith each 



about 



solution 



This confirms the obsen'ation 



* ■ 



sign 



of 



,' chemical action between the substance of the enzyme solul 

 .t of the toxic solution. 



In this test the t^-o salts are neutral in all concentrations tried. 



t 4^^^ of the salt 



The unboiled 



all free from sediment after incubation. Total inhi- 



Une drop of the m/40 KOH gives a deep purple wit 

 solution m any of the concentrations used in the test. 



