A strew slide from Baker’s Island (not sure which Baker’s Island – so far I’ve found one in Hampshire, UK and another in Massachusetts, USA). Range of species. This looks to be by John T Norman, and has a date of 1866 on it.
On the slide it mentions Triceratium favus, Aulacodiscus oreganus, Aulacodiscus margaritaceus, Coscinodiscus sp., Actinoptychus sp., and Eupodiscus sp. I picked on a pair of Biddulphia sp., and an Actinoptychus and something else (maybe a Stephanodiscus sp. or Thalassiosira sp.) for imaging. Olympus BHB microscope using 450nm LED light. 20x Nikon Plan Apo NA 0.65 objective. Olympus Aplanat Achromat condenser, brightfield lighting for the Biddulphia image, and oblique lighting for the other. 2.5x Nikon CF PL photoeyepiece. Monochrome converted Nikon d850 camera. Image stack for the Biddulphia image done in Zerene (13 images Pmax).
This is an interesting slide to view, but not to photograph. I couldn’t use my preferred 40x and 63x Pl Apo objectives, as the coverslip is really thick. As such I was limited to the 20x which impacted resolution (yes, I could use my 50x NA 1.0 water immersion Leitz objective with its long working distance, but the image quality is not the much better than the 20x Nikon). Assuming it is by JT Norman and was made in 1866 it is also historically interesting and one of the oldest slides I have.