Cladophora insignis ( C. A. Ag. ) Kuetzing 1845, p. 217 



PL 21, Figs. 4, 5 

 Floating; the thallus composed of straight, coarse, and sparsely 

 branched filaments, the branches often arising at right angles to 

 the main axis and very slightly smaller. Main filament 75-120/x in 

 diameter, the cells cylindrical or swollen; branches 40-70/i, in 

 diameter, 4-6 times the diameter in lengdi. 

 In hard water lakes. Mich., Wis. 



Cladophora oligoclona Kuetzing 1845, p. 218 

 PI. 21, Figs. 6-8 



Floating or attached; thallus little branched, the branches 

 opposite or dichotomous, the secondary branches bearing many 

 alternate or unilaterally disposed, clavate or thorn-like 1-celled 

 branches. Cells in the main axis cylindrical, 45-55^^ in diameter, 

 2-6 times the diameter in length; branches of the first order 30-40/1, 

 in diameter, the cells cylindrical, up to 10 times the diameter in 

 length. 



In lakes. Wis. 



Cladophora profunda var. Nordstedtiana Brand 1902a, p. 34 



PI. 22, Figs. 1-4 



Thallus composed of attached, irregularly and much branched 

 filaments growing from a prostrate, colorless, rhizoidal portion. Basal 

 branches directed downward and ending in colorless rhizoid-like 

 cells; upper branches irregular in arrangement, often entangled and 

 interlocked to form snarled tufts. Cells irregularly inflated or sub- 

 cylindric, 2.5-50/x in diameter, 36-250^ long in the main axis. Walls 

 of cells encrusted or merely roughened with lime and sometimes 

 with iron deposits, giving a rust-colored appearance to older plants. 



This species has been found growing on rocks at 10-15 meters in 

 Trout Lake, Wisconsin. Well developed plants were found on large 

 stones obtained by dredging, which had rims or ridges of iron 

 deposits at the level where the stone emerged from the bottom 

 sediment. The iron deposit apparently is the same as that noted on 

 the walls of the plant and suggests the possibility of having been 

 laid down by physiological action. 



PITHOPHORA Wittrock 1877, p. 48 



Free-floating, branched, coenocytic filaments of very long, cylin- 

 drical or slightly swollen cells; branches arising at right angles to 

 the main axis. Swollen, cask-like or cylindrical akinetes frequent, 



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