Light micrograph of the freshwater alga Chaetophora spec. Chaetophora forms macroscopic, hemispherical colonies on submerged substrates. The filaments branch very strongly and often form long hairs at the ends of the cells. The cells are cylindrical with ring-shaped chloroplasts with pyrenoids. Image in fluorescence contrast with blue excitation. The chlorophyll of the cells glows in deep red intrinsic fluorescence. Magnification 300x at a print width of 10 cm.