18 



METHOD OF DESTROYING ALG^E IN WATER SUPPLIES. 



Effect of various concentrations of copper sulphate upon different forms ofalgx. 

 [d=dead; vfa=very few alive; vfd=very few dead; g=in good condition.] 



GOROTJIP 1. 

 CHLAMYDOMONAS PIRIFORMIS Dill. 



RAPHIDIUM POLYMORPHUM Fres. 



DESMIDIUM SWARTZII Ag. 



STIGEOCLONIUM TENUE (Ag.) Rabenh. 



DRAPARNALDIA GLOMERATA (Vauch.) Ag. 



NAVICULA Sp. 



