An arrangement of Auliscus hauckii from Bory, Hungary. Prepared by JA Long. The example on the right has 2 frustules, one on top of the other. The other two are single ones, viewed from the underside with the rims towards 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. 74 images stacked in Zerene (Pmax).
There is another example of this diatom on the site from a Bory strew by Samuel Henry Meakin (see here).