green algae - algae that are clear green in color; often growing on wet ricks or damp wood or the surface of stagnant wateralga, algae - primitive chlorophyll-containing mainly aquatic eukaryotic organisms lacking true stems and roots and leaves Chlorophyta, division Chlorophyta - large division of chiefly freshwater eukaryotic algae that possess chlorophyll a and b, store food as starch, and cellulose cell walls; classes Chlorophyceae, Ulvophyceae, and Charophyceae; obviously ancestral to land plants pond scum - free-floating freshwater green algae spirogyra - freshwater algae consisting of minute filaments containing spiral chlorophyll bands stonewort - any of various submerged aquatic algae of the genus Chara having nodes with whorled filamentlike branches; usually encrusted with calcium carbonate deposits desmid - freshwater green algae |