INDEX. 



Abyssal fauna, 5. 



Anabaena, annual distribution of, 15. 



Annual distribution of the organisms of the 



plankton, 11. 

 A nuraea aculeala, annual distribution of, 

 19. 

 cochlearis, annual distribution 



of, 19, 

 guadrvlentata, annual distribu- 

 tion of, 20. 

 Aphanizomenon, annual distribution of, 



16. 

 Apstein, 13, 18, 19, 21, 22, 24, 25, 32. 

 Asplanchna, annual distribution of, 21. 

 Asterionella, annual distribution of, 11,14. 



Balance of life more easily maintained in 



deep lakes, 66. 

 Birge,.9, 24, 25, 26, 32, 33, 57. 

 Bloom, discussion of, 36. 

 Bosmina, annual distribution of, 33. 



table of numbers per square me- 

 ter in Green lake, 84. 

 Burckhardt, 32, 36. 

 Buttes des Morts, 2. 



Centrifuge, use of, 9. 



Ceratium hirundinella, annual distribu- 

 tion of, 18. 

 Characteristic species of deep and shallow 



lakes, 62. 



Chydorus, table of numbers per square 



meter in Lake Winnebago, 85. 



sphaericus annual distribution 



of, 35. 



Classes of lakes, comparison of faunae and 



florae, 62. 

 Classification of lakes, 6. 

 Clathrocyslis, annual distribution of, 15. 

 Clostertum, annual distribution of, 14. 

 Codonella, annual distribution of, 19. 

 Collections, on Green lake, times of, 5, 7. 

 on Lake Winnebago, loca- 

 tions of, 4. 

 method of making, 8. 

 Conochilus volvox, annual distribution of, 



Copepod larvae, annual distribution of, 

 29. 



Counting plankton, method used, 10. 



Crustacea, important in total plankton in 



Z deep lakes, 49, 50. 



Cyelops brevispinosus, annual distribution 



of, 26. 



table of numbers 



per square meter 



in Lake Winne- 



and C pulchel- 

 lus, local distri- 

 bution in Wiscon- 

 sin lakes, 27. 

 Leuckarti, 'annual distribution of, 

 28. 

 table of numbers per 

 square meter in Lake 

 Winnebago, 81. 

 prasinus, annual distribution of, 

 29. 

 table of nnmbers per 

 square meter in Green 

 lake, 81. 

 pulchellus, annual distribution of, 

 27. 

 table of numbers per 

 square meter in Lake 

 Winnebago, 80. 

 and C, brevispinosus, 

 local distribution in 

 Wisconsin, 27. 

 Cyclotella, annual distribution of , 11, 14, 

 Cypris, 36. 



table of numbers per square meter in 

 Lake Winnebago, 86. 



Depth, a factor in horizontal distribution, 



56. 

 Depths of Wisconsin lakes, 87. 

 Diaphanosoma brachyurum, annual dis- 

 tribution of, 30. 

 table of numbers per 

 square meter in Lake 

 Winnebago, 83. 



