Coscinodiscus barbadensis from Springfield, Barbados. Single example on the slide. Prepared by Thomas Edward Doeg and dated 1876. Olympus BHB microscope using 450nm LED light. 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. 31 images stacked in Zerene (Pmax).
Described in Greville, R. K. (1861). Descriptions of new and rare Diatoms. Series I. Transactions of the Microscopical Society, New Series, London. 9: 39-45. page(s): p. 43; pl. 4, fig. 9 As discussed in the ref, this looks to be an Actinocyclus sp. rather than a Coscinodiscus sp..