FIGURES 1–7. 1 in Studies on type material from Kützing's diatom collection VI:The identity of Diatoma liber Suhr (1831)

FIGURES 1–7. 1. Reproduction of Suhr's original figure for Diatoma liber (in Suhr 1834, 17 (1), tab. III, fig. 4; Suhr's illustrations have no scale, the reproduction here is approximately the same size as that in the original, see https://www.biodiversitylibrary.org/page/ 31440#page/, also not to scale). 2–6. Specimens of Diatoma liber from BM 19390 ('Kützing 823', "Ins Canar.", Canary Islands). 7. Reproduction of Kützing's figures for Biddulphia quinquelocularis (in Kützing 1844, p. 138, pl. 19, fig. I, 1, 2). Scale bars: ca. 20 μm.