CONTENTS 



PAGE 



Foreword 5 



Importance of the Problem "7 



Multiplicity and Significance of Aquatic Organisms 9 



Natural and Unnatural Conditions of Aquatic Existence. 11 



General Losses by Stream Pollution 18 



Effects of Domestic Sewage 24 



Effects of Industrial Wastes 25 



Return to Natural Conditions 35 



Biological Examination of Water Bodies , 37 



Preliminary Survey of Stream Conditions 53 



"Recommendations 72 



