Coscinodiscus symmetricus from Oamaru, New Zealand. Single example on the slide with damage to about a quarter of the rim. Prepared by Frederick Marshall. Olympus BHB microscope using 450nm LED light. 63x Leitz Pl Apo NA 1.40 objective, oil immersion. Olympus Aplanat Achromat condenser, oil immersion, strongly oblique lighting. 5x Nikon CF PL photoeyepiece. Monochrome converted Nikon d850 camera. 13 images stacked in Zerene (Pmax).