light blue-green, finely granular; cells 3.3-3.7- (4.5) /a in diameter, 

 5.5-7.5/A long. 



This plant has smaller cells than those described for Aphanothece 

 prasina, and they are not cylindrical. 



Euplankter. Mich., Wis. 



Aphanothece microspora ( Menegh. ) Rabenhorst 1863, p. 76 



PI. 105, Figs. 7-9 



Cells short-cylindric with rounded ends, loosely arranged, solitary 

 or in pairs in small, amorphous, olive or yellow-green gelatinous 

 masses; cells 2.4-2.7/1, in diameter, 6-10jli long. 



Fairly abundant in a few hard water lakes; entangled in tycho- 

 plankton, among filamentous algae. Wis. 



Aphanothece nidulans P. Richter 1884, p. 128 

 PI. 104, Figs. 2, 3 



Cells short-cylindric, broadly rounded at the apices, densely and 

 evenly distributed in small ovate or spherical colonies, inclosed by 

 a colorless mucilage in which individual cell sheaths are not distinct; 

 cells small, l-1.5fi in diameter, 3-3.5/x long; cell contents pale blue- 

 green. 



This is a euplanktonic species, often forming a major portion of 

 a rich flocculent algal population in shallow water, especially in 

 hard water lakes. The minute bacilliform cells give colonies the 

 appearance of a bacterioidal mass. Mich., Wis. 



Aphanothece nidulans var. endophytica West & West 1912, p. 432 



PI. 105, Fig. 16 

 Cells within the mucilage of other colonial Cyanophyta, such as 

 Coelosphaerium and Microcystis, where they are evenly distributed 

 throughout the envelope of the host; cells 0.8-1.5)u. in diameter, 

 2.5-4.5/* long. 



Rare; in the euplankton of lakes of fairly soft water. Wis. 



Aphanothece saxicola Naegeli 1849, p. 60 

 PI. 104, Fig. 1 



Cells cylindrical with rounded ends, 2—3.5 times longer than wide, 

 loosely arranged, solitary or in pairs within amorphous, homo- 

 geneous, and almost colorless mucilage; colonies free-floating or 

 attached; cell contents pale blue-green; cells (l)-1.5-1.8-(2)/x in 

 diameter, 2.8-6/x, long. 



The cells of this species are bacilliform and are almost colorless. 



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