Pediastrum araneosum var. rugulosum (G. S. West) 



G. M. Smith 1916, p. 476 



[P. Boryanum var. rugulosum G. S. West] 



PI. 47, Fig. 3 



A variety differing from the typical in having the adjoined cells 

 distinctly undulated or crinkly. 



Euplanktonic and tychoplanktonic. Mich., Wis. 



Pediastrum hiradiatum Meyen 1829, p. 773 



PL 47, Figs. 5, 6 



Colony perforate, the peripheral cells deeply bilobed, the lobes 



incised; cells adjoined along the lower part of their lateral w^alls; 



inner cells bilobed, the lobes not incised, all walls concave; diameter 



of cells 10-20/.. 



Common in the plankton of many lakes; generally distributed. 

 Mich., Wis. 



Pediastrum hiradiatum var. emarginatum fa. convexum 

 Prescott 1944, p. 356 

 PL 47, Figs. 7, 8 

 Colony perforate (clathrate), cells bilobed at the periphery, the 

 lobes bifurcate, the inner margin of the lobules convex; peripheral 

 cells adjoined along the lower part of their lateral margins only; 

 lobes of inner cells merely emarginate; cells up to 11.7^ in diameter, 

 9.7-10/A long; 16-celled colony 44-50/x wide. 

 Rare, in SpKagnum bogs. Wis. 



Pediastrum Boryanum (Turp. ) Meneghini 1840, p. 210 

 PL 47, Fig. 9; PL 48, Figs. 1, 3 



Colony entire; cells 5— 6-sided with smooth or granular walls; 

 peripheral cells with outer margins extended into 2 blunt-tipped 

 processes; cells up to 14^ in diameter, 21^ long; 36-celled colony 

 85-90/x wide. 



Common in the eu- and tychoplankton of many lakes and swamps; 

 generally distributed. Mich., Wis. 



Pediastrum Boryanum var. longicorne Raciborski 1889, p. 13 



PL 47, Fig. 10 



Peripheral cells with outer margins extended into longer processes 

 than in the typical plant; apices of lobes swollen; cells 20-35- ( 40 )/x 

 in diameter. 



Euplankter. Mich., Wis. 



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