A strew slide from the North Sea (uncleaned). A ‘busy’ slide, with phytoplankton, Rhizosolenia sp., Chaetoceros sp., Biddulphia sp., Coscinodiscus sp. etc. Per Lowestoft Marine Laboratory via Luigi Pastori. Mounted in Aroclor and dated October 1975. No makers name but this is by Bernard Hartley. Olympus BHB microscope using 450nm LED light. I chose a Coscinodiscus sp. fragment for imaging at high magnification. 40x Leitz Pl Apo 1.00 objective, oil immersion. Olympus Aplanat Achromat condenser, oil immersion, oblique lighting. 2.5x Nikon CF PL photoeyepiece. Monochrome converted Nikon d850 camera. 59 images stacked in Zerene (Pmax).
Coscinodiscus sp. (Coscinodiscus concinnus is a good match). Coscinodiscus concinnus W.Smith 1856. Published in: Smith, W. (1856). A synopsis of the British Diatomaceae; with remarks on their structure, functions and distribution; and instructions for collecting and preserving specimens. The plates by Tuffen West. In two volumes. Vol. II. pp. [i]-xxix, 1-107, pls 32-60, 61-62, A-E. London: John van Voorst, Paternoster Row. Page 85. Schmidt’s Atlas Plate 114, Figures 8,9.
There is an entry from Bernard Hartley’s Sample and Strew Slide Collection PDF for this – slide 106A – accessed from here.