Three examples of Auliscus hardmanianus from Jackson’s Paddock, Oamaru, New Zealand. Slide says ‘low contrast’ but they are not too bad. Broken coverslip, but thankfully not near the diatoms. No makers name, but from the style I’d say this was was Henry James Baker. Olympus BHB microscope using 450nm LED light. 63x Leitz Pl Apo NA 1.4 objective, oil immersion. Olympus Aplanat Achromat condenser, oil immersion, oblique lighting. 2.5x Nikon CF PL photoeyepiece. 11mm removed from the tube to the camera to increase the field of view. Monochrome converted Nikon d850 camera. 74 images stacked in Zerene (Pmax).
Auliscus hardmanianus Greville, 1866. Published in: Greville, R.K. (1866). Descriptions of new and rare Diatoms. Series XVIII. Transactions of the Microscopical Society, New Series, London 14: 1-9, pls I,II. Page 6, Plate II, Figure 17. Also see: Desikachary, T.V. & Sreelatha, P.M. (1989). Oamaru diatoms. Bibliotheca Diatomologica 19: 1-330, including 145 plates.