Section Page 



10 Effect of dissolved oxygen on the acute toxicity of 

 armionia to rainbow trout: LC50 vs. D.O. at 5 time 

 intervals 130 



10 Acute toxicity of ammonia to rainbow trout: 96-hour 



LC50 vs. pH 132 



10 Acute toxicity of ammonia to fathead minnows: 96-hour 



LC50 vs. pH 133 



11 The relationship of the number of dead Daphnia magna with 



time under the influence of various concentrations of 

 trimethyl tin chloride 140 



11 Daphnia magna mortality with time as a result of expo- 

 sure to organic tin compounds and some other compounds . . 143 



11 Daphnia magna mortality with time as a result of expo- 

 sure to trimethyl tin chloride in a concentration of 

 1 mg/1 144 



n The relationship of time of death of 25 percent of 



Daphnia magna with the concentration of trimethyl tin 



chloride 150 



11 Graphical determination of acceptable concentrations of 



trimethyl tin chloride for Daphnia magna 153 



13 Outline map of the southern Lake Huron showing the dis- 

 tribution of the eutrophication tolerant diatom 

 Frag il aria capucina Desm. in the waters of Lake Huron 

 outside Saginaw Bay in early June 1974 176 



13 Transmission electron micrograph of a cross section of 



Frag il aria capucina 177 



13 X-ray spectrum of a polyphosphate contained in vacuole 



of Fragilaria capucina 177 



13 Outline map of Saginaw Bay, Lake Huron showing the abun- 

 dance populations containing polyphosphate bodies in 

 different segment of the bay 178 



13 Transmission electron micrograph of Anacystis containing 



large polyphosphate bodies 180 



13 Transmission electron micrograph of Scenedesmus sp. 



showing large polyphosphate bodies in the vacuole .... 180 



XI 



