Pediastrum integrum Naegeli 1849, p. 97 

 PL 48, Figs. 9, 10 

 Colony entire; cells 5-sided; outer margin of peripheral cells 

 smooth or with 2 short and much reduced processes, and granular 

 walls, emarginate between the processes; cells 16-25/* in diameter. 

 A smooth-walled form of this species, fa. glabra Racib., is fre- 

 quently encountered. 

 Euplankter. Mich., Wis. 



Pediastrum integrum var. priva Printz 1914, p. 73 

 PI. 48, Fig. 7 



Colony smaller than the typical plant; peripheral cells trapezoidal, 

 tlie outer margins straight or shghtly retuse. 

 Euplankter. Wis. 



Pediastrum integrum var. scutum Raciborski 1889, p. 5 



PI. 49, Fig. 2 

 Colony entire, 8-64-celled, walls thick; interior cells 5- or 6-sided; 

 peripheral cells 5-sided, rhomboidal, the outer wall convex and 

 without processes, surface of walls and free outer margins furnished 

 with numerous, sharp granules; cells 10-18.5- ( 28 )/* in diameter. 

 Rare, in littoral flora. Mich., Wis. 



Pediastrum Kawraiskyi Schmidle 1897, p. 269 



PI. 50, Fig. 1 



Colony entire; inner cells 4- or 6-sided; peripheral cells napiform 



in vertical view, the outer margin extended into 2 projections which 



are not in the same plane, one usually directly above the other; 



cells 10-20^ in diameter. 



Eu- and tychoplanktonic; common. Mich., Wis. 



Pediastrum muticum Kuetzing 1849, p. 193 

 PI. 49, Fig. 8 



Colony perforate, with 8-64 smooth- walled cells; inner cells 5- 

 or 6-sided; peripheral cells with emarginate outer walls and 2 

 broadly rounded lobes, which are further apart than the lobes of 

 adjacent cells; cells 20/i, in diameter. 



The original description of this plant contains no justification for 

 including it with P. tetras as in DeToni, 1889, Sylloge Algarum, 1 

 (l)p.581. 



Rare, in euplankton. Mich., Wis. 



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