A slide with 2 examples of Auliscus ovalis from Cape Agulhas, South Africa. One viewed from the top, one from the side. Prepared by Dingley P. Fuge. Not sure as to the mountant (although it does say ‘Sx’ – Sirax, perhaps?). Also says R.M. and 1931. Nice gold ring around the coverslip. Olympus BHB microscope using 450nm LED light. 40x Leitz Pl Apo NA 1.00 objective, oil immersion. Olympus Aplanat Achromat condenser, oil immersion, oblique lighting. 2.5x Nikon CF PL photoeyepiece. Monochrome converted Nikon d850 camera. Image stacks prepared in Zerene (Pmax) with one stack for the lower diatom and another for the upper.