Strew slide from William’s Bluff, Oamaru, New Zealand. Range of species present and some sponge spicules. Prepared by Bernard Hartley. Olympus BHB microscope using 450nm LED light. I chose a couple for imaging at higher magnification.
Porodiscus hirsutus. 40x Leitz Pl Apo 1.00 objective, oil immersion. Olympus Aplanat Achromat condenser, oil immersion, slightly oblique lighting. 2.5x Nikon CF PL photoeyepiece. Monochrome converted Nikon d850 camera. 63 images stacked in Zerene (Pmax). Couldn’t use the 63x objective, as it was close to the coverslip ring. There were a couple of these on the slide, both close to the edge of the coverslip unfortunately (isn’t that always the way). Porodiscus hirsutus Grove & Sturt 1887. Published in: Grove, E. & Sturt, G. (1887). On a fossil marine diatomaceous deposit from Oamaru, Otago, New Zealand. Appendix. Journal of the Quekett Microscopical Club, Series 2 3(19): 131-148, pls 10-14. Page 143, Plate 14, Figure 4.
Trigonium lautourianum fragment, also known as Triceratium lautourianum. 20x Nikon Plan Apo 0.65 objective. Olympus Aplanat Achromat condenser, slightly oblique lighting. 2.5x Nikon CF PL photoeyepiece. Monochrome converted Nikon d850 camera. 22 images stacked in Zerene (Pmax). Couldn’t even use the 40x objective for this one, as it was right next to the coverslip ring and mounted quite deep. I’ve also made a very rough composite image showing what it would look like if intact (basically a simple copy and paste job in Photoshop as the fragment was only half of it). Shown in Päule Hecke’s Oamaru book (Bild 560, p164). Accepted name: Triceratium lautourianum Grove in Bergon et al., 1890. Original description: Bergon, P., Cleve, P.T., Grove, E. & Tempère, J. (1890). Diatomées rares ou nouvelles. Le Diatomiste, 1(1): 2-7. Page 6, Plate 1, Figure 5. Interesting one, never found one on a slide before.