A strew slide from Nottingham, Maryland, USA. Fossil, Miocene. Prepared by Klaus Kemp. Mounted in Pleurax and dated January 2003. Olympus BHB microscope using 450nm LED light. 63x Leitz Pl Apo 1.4 objective, oil immersion (40x Leitz Pl Apo NA 1.00 objective, oil immersion, for one image). Olympus Aplanat Achromat condenser, oil immersion, brightfield lighting. 2.5x Nikon CF PL photoeyepiece. Monochrome converted Nikon d850 camera. Image stacked prepared in Zerene (Pmax).
Actinocyclus octonarius var. ralfsii. A lot of these on the slide. Fairly sure of the ID for these.
Lithodesmium ehrenbergii. Viewed from the underside (rim towards to the coverslip). Thanks to Bill Dailey for the ID on this one.
Pseudauliscus spinosus. Again, fairly sure on the ID for this one. Some overlaying debris in the 9 o’clock position, which has muddied the image there. Schmidt’s Atlas Plate 439, Figs 1,2. Discussed in Christian, T. (1887). New Diatomaceous deposits. The Microscope, 7(3): 65-68 page(s): p. 68; fig. [6].