Fine Structure of Cellular Inclusions in Pericarp Cells of Polysiphonia deusta (Ceramiales, Rhodophyta)

The ultrastructure of cytoplasmic inclusions in pericarp cells(cystocarpic plant) of Polysiphonia deusta shows five structuraltypes of inclusions; (1) membrane-bounded crystalloid inclusionsthat are composed of tetragonally packed fibrils, each 8 nmdiam., spaced 17.5 nm between centres; (2) membrane-boundedcrystalloid-like inclusions with incomplete structure; (3) unboundedcrystalline body without a distinct crystal lattice pattern;(4) membrane-limited fibrillar inclusions; (5) fibrillogranularstructure. The membranes of the first two inclusions were coveredwith ribosomes and seem to be elements of endoplasmic reticulum. Polysiphonia deusta, pericarp cells, cellular inclusions