Kirchneriella contorta (Schmidle) Bohlin 1897, p. 20 

 PL 57, Figs. 7, 8 

 Free-floating colonies, usually of 16 twisted, arcuate, cylindrical 

 cells with broad, convex apices, lying irregularly scattered through- 

 out the homogeneous, gelatinous envelope; chloroplast covering the 

 entire wall of the cells, which are 1-2/x in diameter, 5.8-10-(14)/x 

 long. 



Rare; in plankton of several lakes. Mich., Wis. 



Kirchneriella elongata G. M. Smith 1916, p. 473 

 PL 58, Fig. 1 

 Colonies composed of 4-16 elongate-cylindrical, spirally twisted 

 cells which have rounded apices; individuals much entwined near 

 the center of the homogeneous colonial envelope; 1 parietal chloro- 

 plast, without a pyrenoid; cells 2-3/x in diameter, 15-25/x long; 

 colonies up to 100/x in diameter. 



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



Kirchneriella lunaris (Kirch.) Moebius 1894, p. 331 



PL 58, Fig. 2 

 Colony composed of numerous cells arranged in groups of 4-16 

 within a close, gelatinous envelope; cells flat, strongly curved 

 crescents with rather obtuse points; chloroplast covering the convex 

 wall; cells S-Sfi in diameter, 6.5-13/x long; colonies 100-250/x in 

 diameter. 



Common in the plankton of open water or among mats of algae 

 in the shallow water of acid ponds and lakes. Mich., Wis. 



Kirchneriella lunaris var. Dianae Bohlin 1897, p. 20 



PL 58, Fig. 3 

 A variety differing from the typical in having very strongly curved 

 cells with sharply pointed apices which are not in the same plane; 

 cells 3-5/x in diameter, 10-18-(21)/x long. 



Rare; in plankton of several lakes especially in acid habitats. 

 Mich., Wis. 



Kirchneriella lunaris var. irregularis G. M. Smith 1920, p. 142 



PL 58, Fig. 4 

 A variety differing from the typical by having the apices distinctly 

 twisted and very evidently pointing in different directions so that 

 a spiral sigmoid curve is produced; cells 4-6/i, in diameter, 6-13^ 

 long. 



Rare; in plankton of a variety of lakes. Wis. 



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