An arrangement of Plagiogramma elongatum from Rio de Janeiro. Described as ‘rare’. Prepared by Arthur Charles Cole. I selected one for imaging at higher resolution using a 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. 32 images stacked in Zerene (Pmax).
Plagiogramma elongatum Greville 1866. Published in: Greville, R.K. (1866). Descriptions of new and rare Diatoms. Series XX. Transactions of the Microscopical Society, New Series, London 14: 121-130, pls XI, XII. Page 121, Plate XI [11], Figures 1,2.