Aphanothece Castagnei (de Breb. ) Rabenhorst 1865, p. 76 



[Anacystis tJiarginata Meneghini 1837] 



PI. 105, Figs. 5, 6 



Cells ellipsoid or ovate to subcylindric, densely arranged within 

 a gelatinous, amorphous mass which is olive-green or brownish; cells 

 of various shapes and sizes within the same colony, oblong or poly- 

 gonal when compressed; 2-3.5yu, in diameter, 4-8/x long; cell contents 

 finely granular and olive-green. 



In ditches; in tychoplankton of lakes. Wis. 



Aphanothece clathrata G. S. West in West & West 1906, p. Ill 



PL 104, Figs. 6, 7 



Colonies free-floating, irregular in shape and usually clathrate 

 with large perforations; cells cylindrical or elongate-elliptic, sti'aight 

 or slightly curved, scattered through a ti^ansparent mucilage; cells 

 0.8-1. 2/A in diameter, 3-6/x long. 



The small size of this species and the clathrate colony are char- 

 acters which separate this species from most of the other free-floating 

 forms of Aphanothece. Its lack of pseudovacuoles differentiates it 

 from A. pulverulenta Bachmann, another species with minute cells 

 (ellipsoid in shape) which possess pseudovacuoles. 



Floating in several soft water lakes. Mich., Wis. 



Aphanothece gelatinosa ( Henn. ) Lemmermann 1910, p. 69 



PI. 104, Fig. 8 

 Cells ovate, nearly spherical, compactly arranged in globular, 

 blue-green to brown gelatinous attached masses; cell contents blue- 

 green; cells 3.8-4/i, in diameter, 4— 4.5/x long. 



This plant is differentiated by the color of the colonial mass and 

 by the size of the cells from Aphanothece stagnina. It is possibly 

 only a variation of that species, and the assigned name is used here 

 tentatively to designate a form which does not agree with typical 

 A. stagnina. I have not seen type specimens of A. gelatinosa for 

 comparison. 



In a hard water swamp and in lakes with a high calcium carbonate 

 content. Wis. 



Aphanothece microscopica Naegeli 1849, p. 59 

 PI. 104, Figs. 9, 10 

 Cells ovate to subglobose, densely arranged in small, free-floating 

 or attached ovate colonies; cell sheaths not evident; cell contents 



[467] 



