10. Experimental Testing of Toxicity of Water Media and 

 Increasing of the Sensitivity of Biological Tests 



L.P. Braginski, V.D. Bersa, T.I. Biger, I.L. Burtnaya, 



F.Ya. Komarovski, A.Ya. Malyarevskaya, E.P. Shcherban . . 102 



11. Chronic Effects of Low Levels of Hydrogen Sulfide on 

 Freshwater Fish 



Lloyd L. Smith, Jr 113 



12. The Behavioral Aspects of Aquatic Toxicology 



B.A. Flerov 122 



13. Geologic Pollution Problems of Lake Superior 



Albert B. Dickas, Ph.D 133 



14. Experimental Application of Various Systems of Biological 

 Indication of Water Pollution 



G.G. Winberg 141 



15. Structural and Functional Characteristics of Seston as 

 Indices of Water Pollution 



A. P. Ostapenya 150 



XT 11 



