Lijnghija versicolor ( Wartmann ) Gomont 1892a, p. 147 



PL 113, Fig. 4 

 Plants forming a mucous expansion on submerged objects, be- 

 coming detached and floating; filaments much entangled; trichomes 

 not tapering toward the apices and not constricted at the cross 

 walls, which are not granular; cells 2.8-3.4;a in diameter; filaments 

 3-3.8-(5)/A in diameter; sheaths thick (up to 2/x), mucous. 



Forming compact films on submerged logs; tychoplankter. Mich., 

 Wis. 



SYMPLOCA Kuetzing 1843, p. 201 

 Unbranched sheathed filaments, united in branching bundles or 

 fascicles which are erect or growing out and away from the sub- 

 strate to which they are attached (rarely free-floating); trichomes 

 uniseriate and straight, tapering distally but very sfightly; apical 

 cell conical or broadly rounded, sometimes with a thickened outer 

 membrane; sheaths firm and close, or confluent in the median 

 portion of the filament only, thus producing the effect of false 

 branching; cells quadrate or cylindric, slightly, if at all, constricted 

 at the cross walls. 



Symploca muscorum ( C. A. Ag. ) Gomont 1890, p. 354 



PI. 113, Fig. 7 



Filaments forming brownish-green, erect or procumbent tufts 

 or fascicles (often producing Phormidium-like expansions); tri- 

 chomes straight or wavy, parallel; cells quadrate to cylindrical, not 

 constricted at the cross walls, 5-8/x in diameter, 5-1 1/a long; cell 

 contents densely granular; apical cell broadly rounded or obtuse- 

 conical; sheaths firm, thin, close. 



Along sides of ditches and in Sphagnum bogs; rare in our collec- 

 tions, although a widely distributed and common species. Mich., Wis. 



HYDROCOLEUM Kuetzing 1843, p. 196 

 Trichomes few to several in relatively wide, lamellate, and color- 

 less sheaths, which are in part close and definite, becoming diflluent, 

 the sheaths sometimes branching; forming a cushion-like expanse 

 (sometimes lime-encrusted); individual trichomes tapering slightly 

 at the apices, the terminal cell usually capitate and sometimes with 

 a calyptra; cells quadrate or shorter than wide. 



Hydrocoleum oligotrichum A. Braun in Rabenhorst 1865, p. 294 

 Plant mass cushion-like, lime-encrusted, and brownish in color; 

 trichomes clustered in bundles, 2-6 within a lamellate sheath, 



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