194 WISCONSIN PHYTOPLANKTON 



PLATE 75. 



All figures x 500, 



Page 



Figs. 1-3. Staurastrum BuUardii sp. nov 91 



Figs. 4-5. Staurastrum vestitum Ealfs formae 92 



Figs. 6-10. Staurastrum vestitum var. subanatinum W. & G. S. West 93 



Figs. 11-16. Staurastrum anatinum var. longibrachiatum W. & G. S. West.. 94 



Figs. 17-20. Staurastrum anatinum var. curtum G. M. Smith 95 



Figs. 21-25. Staurastrum anatinum var. denticulatum var. nov 95 



