Aphanocapsa elachista var. planctonica G. M. Smith 1920, p. 42 



PL 101, Fig. 12 



Cells less crowded than in var. conferta, evenly dispersed through- 

 out a colorless, colonial mucilage, 2-3/^ in diameter. 



Euplankter. Rare in several, mostly soft w^ater, lakes. Mich., Wis. 



Aphanocapsa endophytica G. M. Smith 1920, p. 42 

 PI. 101, Fig. 13 



Endophytic in the colonial mucilage of Microcystis; cells solitary or 

 arranged in small clumps which are evenly dispersed and remote 

 from one another; cell contents homogeneous, pale to bright blue- 

 green; cell 2fi in diameter. 



Reported as common in Poor Farm Lake, Wisconsin. 



Aphanocapsa Grevillei ( Hass. ) Rabenhorst 1865, p. 50 



PL 101, Figs. 15, 16 



Free-floating colonies, sometimes on moist soil, spherical or, in 



age, irregularly shaped; cells in pairs, in groups of four and crowded, 



or solitary, evenly dispersed through colorless mucilage, blue-green, 



with pseudovacuoles, 3.8-5.5/i, in diameter. 



Rare; in the tychoplankton of several lakes. Mich., Wis. 



Aphanocapsa pulchra ( Kuetz. ) Rabenhorst 1865, p. 49 



PL 101, Fig. 14 



Colonies ovate or globose, free-floating; cells spherical, loosely 

 and evenly dispersed within a copious mucilage, contents blue- 

 green, finely granular, 3.4-4.5/x in diameter. 



This is the most common species of the genus in our collections 

 of phytoplankters. It is often a component of water blooms in hard 

 water lakes although not infrequently found intermingled and 

 attached among other algae in shallow water of Sphagnum bogs. 

 The colonies often attain macroscopic size. Mich., Wis. 



Aphanocapsa rivularis (Carm.) Rabenhorst 1865, p. 49 



PL 101, Fig. 17 

 A free-floating or sessile, amorphous, or tubular to spherical 

 colony of globose cells which have bright blue-green, granular 

 contents; cells solitary or in pairs and scattered at some distance 

 from one another within the colonial mucilage; cells 5-6/i, in diameter. 

 The slightly larger size of the cells, and the more scattered ar- 

 rangement separate this species from A. Grevillei. 

 Euplankter. Mich., Wis. 



[454] 



