STRUCTURE AND COMPOSITION OF OOCYSTIS POLYMORPHA CELL WALLS ISOLATED FROM THE CULTURE MEDIUM 1

SUMMARY Oocystis polymorpha and possibly other algae which shed their parent‐cell walls during reproduction appear to be suitable organisms for cell wall research in that the cell walls can be readily collected from the culture medium. Electron micrographs of sectioned isolated cell walls, of the parent‐cell walls, and of the daughter cells appear to be identical, suggesting that the isolated cell walls are representative of those of the intact cell. Chemically, the cell walls of Oocystis polymorpha resemble the cell walls of Cyanidium and the chemically resistant cuticle fraction of Cladophora and Porphyra in their high nitrogen and low sugar and lipid contents. Pink carotenoids are the major lipid components of the cell walls.