The stainable polyphosphate bodies in five species of algae epiphytic on Cladophora glomerata were enumerated. The algal populations, two species of diatoms, two species of blue-green algae, and a red alga, were collected at various distances from a point source of phosphorus enrichment in Lake Huron. Populations assayed had accumulated polyphosphate bodies and exhibited different levels of maximum polyphosphate body abundance. Numbers of polyphosphate bodies per unit cell volume were least in the diatoms, greatest in the blue-greens, and intermediate in the red alga. (Copyright (c) 1982, by the American Microscopical Society, Inc.)