4 Contents 



5. ]\Iacroplankton of Lake Erie — (Continued) page 



Horizontal distribution 69 



Marginal zone 69 



Littoral zone 69 



Lacustric zone 70 



Summary 72 



List of species 74 



Copepoda 74 



Cladocera 75 



Other Crustacea 76 



6. Contributions to the early life history of Lake Erie fishes 76 



Problem 76 



Methods 76 



Sunmiary of results 78 



Table 4. Record of species of young fishes 79 



Table 5. Station record of young fishes 81 



Family Coregonidae 82 



Family Percidae 90 



Family Centrarchidae 93 



7. Seining records and food of the intermediate stages of Lake Erie fishes . . 95 



Table 6. Record of stomach contents 96 



Summary and conclusions 100 



Physical hydrography 100 



Bacteriology and chemistry 101 



Biology 102 



Table 7 104 



General discussion 106 



Section III. Chemical investigation of the Erie-Niagara watershed 107 



Types of pollution 107 



Methods employed 107 



Classification of data 110 



Lake Erie studies 110 



Niagara river 112 



Other streams 114 



Cattaraugus creek 117 



Tables 120 



Series I: Chemical analyses — shore waters of Lake Erie 120 



Series TI: Chemical analyses — water of Niagara river 124 



Series III: Chemical analyses — streams of Erie-Niagara watershed 127 



Series IV: Chemical analyses — Cattaraugus creek 132 



Section IV. Biological investigations of pollution in the Erie-Niagara watershed 134 



Methods 134 



Lake Erie and Niagara river 134 



Sewage and industrial pollution 135 



Milk pollution 136 



Oil, acid and iron pollution 136 



Cilue and tannery wastes 136 



Tabulation of pollution studies in Erie-Niagara watershed 138 



Indicators tolerant of sewage pollution in Erie-Niagara watershed 139 



Section V. Studies upon the fish blood and its relation to stream pollution 140 



The blood of fish as a reflection of external environment 140 



Experiments upon fish blood 141 



Table 1. Hemoglobin and erythrocyte values of the blood of normal fish 144 



EfTects of weak acid solution upon fish 145 



Table 2. Effects upon fish blood of increasing the hydrogen ion concentration 



of the surrounding water 146 



Table 3. Normal numbers of erythrocytes to yield 100% hemoglobin 147 



Table 4. ICiTect of blood removal upon rock bass 148 



Table 5. I'-fTect of blood removal upon lake catfish 148 



Table 6. ElTect of blood removal upon carp 148 



Tabhe 7. Effect of blood removal upon common bullhead 149 



Table 8. Effect of blood removal upon pickerel 149 



