Ankistrodesmus Braunii (Naeg. ) Brunnthaler 1915, p. 189 



PI. 46, Fig. 8 



Cells relatively broadly fusiform, lateral margins convex but 

 irregularly so, narrowed at either pole to short points (not drawn 

 out into long needle points as in most species of the genus); 

 chloroplasts 2 parietal plates; cells 8-10/a in diameter, 20-25-56(a 

 long. 



Tychoplankter. Mich. 



Ankistrodesmus convolutus Corda 1839, p. 199 

 PL 55, Fig. 3 

 Solitary or in groups of 2-4 cells, fusiform in shape, twisted and 

 sigmoid; apices sharply pointed and often twisted in opposite 

 directions; cells 3-4.5/i, in diameter, 15-25/x long. 

 Common in the tychoplankton. Mich., Wis. 



Ankistrodesmus falcatus (Corda) Ralfs 1848, p. 180 

 PI. 56, Figs. 5, 6 



Cells needle-Hke to somewhat spindle-shaped, solitary or in 

 clusters of 2-32 individuals, not inclosed in a colonial sheath; 

 chloroplast 1, ^ parietal plate without pyrenoids; cells 2-6/x in 

 diameter, 25-100/i, long, sometimes longer. 



Ubiquitous; intermingled with other algae and most commonly 

 found in acid water habitats of high temperatures where there is 

 a dense conglomeration of unicellular and colonial algae. Mich., Wis. 



Ankistrodesmus falcatus var. acicularis ( A. Braun ) 



G. S. West 1904, p. 223 



PL 56, Fig. 16 



Cells solitary and almost straight, the outer wall slightly curved 



in the median portion, extended into long, finely drawn out apices; 



chloroplast extending over % of the cell wall; cells 2.5/x in diameter, 



36-65/t long. 



Tychoplankter; rare in several lakes. Mich., Wis. 



Ankistrodesmus falcatus var. mirabilis ( West & West ) 

 G. S. West 1904, p.224 

 PL 56, Fig. 10 

 Cells sigmoid or lunate, apices gradually tapering to fine points; 

 cells solitary, 2-3/* in diameter, as much as 150ju, long. 

 Generally distributed. Mich., Wis. 



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