Aulacodiscus debyi (7 processes) from Oamaru, New Zealand. Single example on the slide, with a yellowed mountant and a couple of nasty cracks in the coverslip. Prepared by Sydney Chaffers. Olympus BHB microscope using 450nm LED light. 20x Nikon Plan Apo 0.65 objective. Olympus Aplanat Achromat condenser, slightly oblique lighting. 2.5x Nikon CF PL photoeyepiece. Monochrome converted Nikon d850 camera. 54 images stacked in Zerene (Pmax).
Original description: Pantocsek, J. (1886). Beiträge zur Kenntnis der Fossilen Bacillarien Ungarns. Teil I, Marine Bacillarien. Nagy-Tapolcsány, Buchdrucherei von Julius Platzko, 74 pp., 30 pls. Page 58, Plate 25, Figure 226. Synonymised name: Aulacodiscus margaritaceus var. debyi (Pantocsek) Rattray, 1888.