Equilibrium in the Intake of Salts by Plant Cells. 457 



clearly indicates that absoption increasing with increasing concentrations 

 has taken place from the aluminium sulphate solutions. 



Table YI. — Carrot in Aluminium Sulphate of various Concentrations. 







Increase 



in electrical conductivity. 





Time. 



Distilled 

 water. 



N/5000. 



N/500. 



]sr/50. 



N/10. 



0- 25 



1- 5 

 12 -42 

 14 -5 

 21 -75 

 38-75 

 45 



4 57 



+ 112 

 + 98 



+ 110 



+ 32 



+ 109 

 + 88 



+ 84 



+ 112 



+ 166 

 + 159 

 + 176 

 + 136 



+ 93 

 + 184 

 + 423 

 + 405 

 + 436 

 + 590 

 + 542 



+ 42 



+ 130 

 + 345 



+ 375 

 + 550" 

 + 520 



Discs waslied 28 hours, running tap water and five changes of distilled water. 



10 20 30 40 50 



TIME IN HOURS 



Fig. 4. — Change in electrical conductivity of external solution when carrot is immersed 

 in aluminium sulphate of various concentrations. 



375 grs. carrot in 750 c.c. of a 0-056 per cent, solution of Al2(S04)3. 

 Estimation of Alfi^ in 200 c.c. before experiment, 0-0337 grs. 

 After two days 0'0055, absorption ratio 11 '33. 

 After four days 0-0038, absorption ratio 16-89. 



Meurer's internal concentrations from which his absorption ratios are calculated are 

 based, not on the tissue volume as in our case, but on the water content of the tissue. 

 He concludes that the aluminium is principally absorbed by the cell-walls. 



