CONTENTS 



Page 



Preparation of cultures 228 



Liquid culture medium 228 



Sterility 228 



Illumination of cultures 229 



Temperature 229 



Inorganic-phosphate determination 229 



Preparation of algal cells for experiments 229 



Determination of population size 229 



Growth rates and interactions of Chlorella and Nitzschia 229 



Growth curve and division rate of Chlorella 229 



Growth curve and division rate of Nitzschia 230 



Interactions of Chlorella and Nitzschia 232 



In initially enriched medium 232 



In medium enriched daily 233 



In buffered medium 233 



In aerated medium 234 



On solid agar 235 



Inhibition of growth rate in conditioned media 236 



Inhibitory effect on Chlorella of iVitesc/iia-conditioned medium 236 



Inhibitory effect on Nitzschia of CWoreHa-conditioned medium 237 



Inhibitory effects of filtrate from conditioned media 237 



Inhibitory effect on Chlorella and Nitzschia of Paredorma-conditioned pond water. 239 



Effect of varying the initial concentrations of Nitzschia and Chlorella 241 



Inhibitory effect on Chlorella of increased concentrations of Nitzschia 241 



Inhibitory effect on Nitzschia of increased concentrations of Chlorella 242 



Effect of antagonistic substances on phytoplankton growth 242 



Summary 244 



Literature cited 245 



