FIGURES 1–4 in Morphology and taxonomy of Psammodiscus Round & Mann (Bacillariophyceae: Rhaphoneidales) with a description of the new species Psammodiscus calceatus

FIGURES 1–4. Psammodiscus nitidus (LM). Figs 1a, b: Solitary cells attached to sand grains, living cells from TW153 (BF), solitary attached cells (two circles in fig. 1b) to a sand grain (figs 2a and b are the same image at different focal depths). Figs 2–4. Valves (BF): Fig. 2 from TW166, figs 3 and 4 from TW159. Scale bars = 50 µm (Fig. 2), 10 µm (Figs 3–5).