186 WISCONSIN PHYTOPLANKTON 



PLATE 71. 

 All figures x 500. 



Page 



Figs. 1-4. Staurastrum setigerum var. occidentale W. & G. S. West 80 



Figs. 5-8. Staurastrum setigerum var. peetinatum W. & G. S. West 80 



Figs. 9-13. Staurastrum setigerum var. brevispinum G. M. Smith 80 



Figs. 14-15. Staurastrum minnesotense WoUe 81 



Figs. 16-20. Staurastrum spiculiferum sp. nov 82 



