A strew slide from Ditchfield Park, Mansfield, UK. Material from H Gleave, collected May 1941. Mounted in Aroclor and dated April 1975. Prepared by Bernard Hartley. Olympus BHB microscope using 450nm LED light. I chose an example of a Diatoma sp. (I think perhaps Diatoma vulgaris) for high magnification imaging. 63x Leitz Pl Apo 1.4 objective, oil immersion. Olympus Aplanat Achromat condenser, oil immersion, oblique lighting. 2.5x Nikon CF PL photoeyepiece. Monochrome converted Nikon d850 camera. 14 images stacked in Zerene (Pmax). Note the single rimoportula visible towards the bottom left of the diatom.
Diatoma vulgaris Bory 1824. Published in: Bory de Saint-Vincent, J.B.G.M. (1824). Diatome. Diatoma. In: Dictionnaire Classique d’Histoire Naturelle. CRA-D. (Audouin, I. et al. Eds) Vol. 5, pp. 461. Paris: Rey et Gravier; Baudouin Frères. Page 461, Figure 1.
This is slide 658 from Bernard Hartley’s Sample and Strew Slide Collection PDF (accessed from here).