Light micrograph of the freshwater eye flagellate Phacus orbicularis. Phacus belongs to the class Euglenophyceae and forms large, mostly flattened cells with a rigid shell. At the front end of the cell there is a swimming flagellum and usually a red eye spot. The cells have a large nucleus, many chloroplasts without pyrenoids and paramylon grains as storage material. Culture material from the algae collection at the University of Cologne (CCAC). Microscopic contrast method : Differential interference contrast. Magnification 600x at a print width of 10 cm.