Phacus Nordstedtii Lemmermann 1904, p. 125 

 PL 88, Fig. 1 



Cells napiform, nearly spherical but with a long, straight, sharply 

 pointed caudus; broadly rounded anteriorly; periplast forming an 

 envelope widely separated from an elliptical protoplast, the periplast 

 spirally striated; paramylon bodies not observed; chloroplasts num- 

 erous ovoid indistinct discs; cells 18.5/x in diameter, 36/a long. 



Our specimens are assigned here because of the cell shape and 

 periplast characteristics. Judging from the original description of 

 P. Nordstedtii, it was not clear to the author of the species whether 

 the species actually belonged to Phacus. Our specimens are much 

 smaller than the dimensions given for this species and perhaps 

 should be described as a new variety. This shouild be deferred, 

 however, until more is learned of their cytology. 



Plankter; from a cedar swamp. Wis. 



Phacus orbicularis Huebner 1886, p. 5 

 PI. 87, Fig. 10 



Cells orbicular in outline, with a short caudus curved to the right 

 (when seen in ventral view); broadly rounded anteriorly; periplast 

 finely striated longitudinally; flagellum as long as the body; para- 

 mylon bodies 2 disc-shaped plates; cells 39-45/a in diameter, 60-70- 

 100/x long. 



Plankter; from a cedar swamp. Wis. 



Phacus orbicularis var. caudatus Skzortzow 1928, p. 112 



[P. platalea Drezepolski ex Pochmann 1942, p. 179] 



PI. 87, Fig.l2; PI. 88, Fig. 15 



Cells broadly ovoid to nearly round in outline, spirally twisted, 

 extended posteriorly into a long, straight, sharply pointed caudus; 

 periplast longitudinally striated; paramylon bodies 1-2 (sometimes 

 several ) large circular plates; cells 45-47/a in diameter, 65-69/a long. 



With the typical form in a cedar swamp. Wis. 



Phacus orbicularis var. Zmudae Namyslowski 1921 



[P. circulatus Pochmann 1942, p. 177] 



PL 88, Fig. 10 



Cells orbicular in outline, produced posteriorly to form a short 

 caudus obliquely turned to the left (as seen in ventral view); peri- 

 plast longitudinally striated; cells 18.5-21ju, in diameter, 27-29/t long. 



In a roadside fosse. Wis. 



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