162 WISCONSIN PHYTOPLANKTON 



PLATE 59. 



All figures x 400. 



Page 



Figs. 1-2. Micrasterias pinnatifida (Ktz.) Kalfs 41 



Fig. 3. Micrasterias laticeps Nordst 41 



Fig. 4. Micrasterias depauperata var. Kitchelii (Wolle) "W. & G. S. "West 42 



Fig. 5. Micrasterias denticulata De Breb 45 



Figs. 6-7. Micrasterias conferta var. hamata Wolle 44 



