ipoS] OSTERHOUT— ACTION OF MAGNESIUM AND POTASSIUM 119 



A large Spirog}Ta of the majuscula type was used for experiments 

 with the stronger solutions. The results are given in Table III. 



-TABLE III 



Fresh- WATER Algae 



All quantities given are cubic centimeters of .0937W 



solutions 



Culture solution 



Duration of life in days: 

 Spirogyra species 



KCl 



100 KCl 

 40 MgCU 



MgCl. 



Distilled water 



i 



12 



25 + 



The plus sign indicates that the plants were aUve at the end of the 



experiment. 



A series of experiments was next made with 

 the gemmae of Lunularia. These were allowed 

 to float on the surface of the solutions. A 

 large number was used and the average results 

 given in the following table. 



TABLE IV 



Liverworts 



All quantities given are cubic centimeters of .0937^ 



solutions 



Culture solution 



Duration of life 



in clan's: 



gemmae <^ Lunularia 



KCl 



\ 



100 KCl 

 50 MgCI. ) 



100 KCl } 

 100 MgCl. 5 



50 KCl ) 

 1 00 MgClj ) 



12 



120 + 



T20-f- 



M^Cla 



Distilled water 



100 



4 



120 + 



The plus sign indicates that the plants wctc alive at the end of the 



^periraent. 







I 



2 







3 



Tig, I. — Growth 



of Vaucheria during 

 45 days in . oi«i solu- 

 tions, r, KCl, gain 

 o; 2, ioo<=c KCl 



4-40CC MgCla, 



4200%; J, MgU 

 gain o. X 25. 



a» 



