In phase contrast the massive layer of mucilage around the algal filament is clearly visible. On the lower right another filament of H. dissiliens stands perpendicularly providing an apical view which shows the stelloid form of chloroplasts. The scale bar indicates 50 µm.
Collected from bottom sediments of a tiny pond at the island of Hiddensee (Baltic Sea, Germany). Images were taken using Zeiss Standard with Olympus C7070 CCD camera.