PLATE 46 



A. — Seedlings, 3 days old, grown in (i) distilled water, (2) 4,000 parts per million 

 sodium-sulphate solution, (3) 4,000 parts per million sodium-sulphate solution + 30 

 parts per million of potassium chlorid, (4) 4,000 parts per million sodium-sulphate 

 solution -{- 30 parts per million of sodium nitrate, (5) 4,000 parts per million sodium- 

 sulphate solution + excess ferric hydrate, and (6) 4,000 parts per million sodium- 

 sulphate solution + aluminum hydrate. 



B. — Seedlings, 11 days old, grovsTi in (i) 2,500 parts per million sodium-bicar- 

 bonate solution, (2) 2,500 parts per million sodium - bicarbonate solution -\- 30 

 parts per million of sodium nitrate, (3) 2,500 parts per million sodium-bicarbonate 

 solution -f- 30 parts per million of potassium chlorid, (4) 2,500 parts per million sodium- 

 bicarbonate solution -f 30 parts per million of magnesium sulphate, and (5) 2,500 parts 

 per million sodium-bicarbonate solution -f 30 parts per million of calcium oxid. 



