PJmcus acuminatus var. Drezepolskii Skvortzow 1928, p. 113 



[P. caudatus Ehrenberg ex Pochmann 1942, p. 146] 



PL 88, Figs. 17, 18 



Cells ellipsoid or ovoid, slightly produced posteriorly, sometimes 

 with the cell margins convolute, forming a short, sharp caudus; 

 periplast longitudinally striated; paramylon bodies 2 large discs; 

 cells 10-15/x in diameter, 21-24^ lo^ig- 



In svi^amps and ditches. Wis. 



Phacus alatus Klebs 1883, p. 312 



Cells very broadly ovoid to nearly circular in outline, with a short 

 caudus which is strongly curved and twisted to the left (when the 

 cell is seen in ventral view); periplast longitudinally striated; para- 

 mylon bodies 2 large plates or rings which are at least Yo the cell 

 body in length, lateral and sometimes peripheral, one on either side 

 of the cell; cells (16)-19-22/x in diameter, 19-24jii long. 



In a slough; among dense growths of filamentous algae. Wis. 



Phacus anacoelus Stokes 1888, p. 91 

 PI. 87, Figs. 7, 8; PI. 88, Fig. 11 



Cells broadly ovoid, narrowed abruptly posteriorly to form a short 

 caudus, which turns to the left ( as seen in ventral view ) ; paramylon 

 bodies 1-2 circular plates; lateral margins of cells with 2-3 creases 

 or folds, the membrane convex between the indentations; periplast 

 longitudinally striate; cells 32-36- ( 40 )/a in diameter, 40-48/x long. 



Euplanktonic and tychoplanktonic. Wis. 



Phacus anacoelus var. undulata Skvortzow 1928, p. 109 



[Phacus undulatus Pochmann 1942, p. 191] 



PI. 87, Fig. 3 



Cells broadly ovoid, produced posteriorly into a long (or short) 

 sharply pointed caudus, oblique to the longitudinal axis of the cell, 

 anteriorly broadly rounded but slightly bilobed because of the 

 gullet groove; periplast longitudinally striated; margin of the cell 

 with 2-3 bulges; 1 large centrally located paramylon disc; cells 

 60-65/x in diameter, 80-1 11/x long. 



Our specimens average much larger than the dimensions recorded 

 for this variety, but otherwise they are in agreement. 



Planktonic; also found in swamps and ditches. Wis. 



[397 ] 



