A strew slide of fossil diatoms from Nottingham, America. Prepared by Norman. Image of an Actinoptychus sp. (maybe heliopelta) viewed from its underside. Olympus BHB microscope using 450nm LED light. 40x Leitz Pl Apo NA 1.00 objective, oil immersion. Olympus Aplanat Achromat condenser, oil immersion, brightfield lighting. 2.5x Nikon CF PL photoeyepiece. Monochrome converted Nikon d850 camera. 25 images stacked in Zerene (Pmax).