Cerataulus johnsonianus from Nagy Curtos, Hungary. Single example on the slide. Now known as Biddulphia johnsoniana. Prepared by Samuel Meakin. Mounted in Styrax, dated 1930. Olympus BHB microscope using 450nm LED light. 63x Leitz Pl Apo NA 1.40 objective, oil immersion. Olympus Aplanat Achromat condenser, oil immersion, standard brightfield lighting. 2.5x Nikon CF PL photoeyepiece. Monochrome converted Nikon d850 camera. 31 images stacked in Zerene (Pmax).