Phacus Segretii var. ovum Prescott 1944, p. 369 

 PI. 88, Fig. 23 



Cells larger than in the typical form, broadly ovoid; 28-30/x in 

 diameter, 39-41|U, long. 

 In swamps. Wis. 



PJiacus Spirogyra Drezepolski 1925, pp. 234, 267 



Cells unsymmetrically spherical or ovoid, with a sharply pointed 

 caudus arising from the broadly rounded posterior; periplast spirally 

 striated with rows of granules; cells 32;u in diameter, 45/* long, caudus 

 10/i, long. 



Typical form not observed in our collections. 



Phacus Spirogyra var. maxima Prescott 1944, p. 369 

 PI. 87, Figs. 4-6 



Cells ovoid to somewhat oblong, unsymmetrically spiral or merely 

 twisted once, abruptly narrowed posteriorly into a long straight or 

 curved caudus; broadly rounded anteriorly (narrowly rounded when 

 seen from the side), with a prominent median protrusion; periplast 

 longitudinally striated with spiral rows of granules; chloroplasts 

 numerous discs; paramylon bodies 2 large doughnut-shaped rings; 

 cells 35-40^ in diameter, 70-80/i, long. 



This species is peculiar in the shape of the cell body which is not 

 very much flattened. In side view it is narrower than when seen 

 from the front. 



In a roadside fosse. Wis. 



Phacus suecicus Lemmermann in Pascher 



& Lemmermann 1913, p. 139 



PI. 88, Figs. 2, 3 



Cells broadly ellipsoid or ovate, but not quite symmetrical, with 

 a relatively long, sharp caudus which is slightly deflected; truncate 

 or slightly retuse at the anterior end but with a prominent, median, 

 collar-like papilla through which the flagellum extends; flagellum 

 as long as the cell body; cell planoconvex when seen from the side; 

 periplast longitudinally striated with rows of sharp granules; chloro- 

 plasts numerous circular discs; paramylon bodies 2 lateral and 

 peripheral plates or rods lying just within the periplast; cells ( 14 ) - 

 19-22/x in diameter, 34-36/* long, 6-11/* thick. 



Plankter; in a cedar swamp. Wis. 



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