Color enhanced scanning electron micrograph showing an Euglena sp., a fresh water protozoan. It belongs to the class of Flagellata whose members are characterized by one or more flagella and which are considered the most primitive form of the protozoa. Members of the genus Euglena are normally found in water puddles in such large numbers that they color the water green. Euglena sp. may feed, depending on environmental conditions, like plants (photosynthesis) or like animals, or both. They have a spindle-shaped body with a flagellum attached anteriorly; the external surface consists of a firm but elastic envelope. Magnification: x180 at 35mm size.