FIG. 1. — Okellya marina (Womersley) Wetherbee, comb. nov. (strain 56a) from New South Wales: A, tuft of filaments; B, C, newly formed filaments of two and four cells attached by a discoid holdfast (asterisks), apical cells rounded; D, larger filaments occur with dense cytoplasm; E, F, filaments showing a single pyrenoid at the center of cells (arrowheads); G, H, pyrenoids stained with iodine solution (arrowheads); I-M, elongate zoospores (s) have differentiated in an intercalary cell (I) and escape from a pore at the apical end of cells (J-M: arrows); zoospores often fail to escape through the pore and germinate inside the sporangium (K-M), occasionally even forming holdfasts (asterisk in M). Scale bars: A, 50 μm; B, D-I, 10 μm; C, J-M, 20 μm.