A strew from Cherryfield, Maine, USA. Fossil freshwater material. Prepared by Watson and Sons Ltd. Usual selection of species for Cherryfield, however I selected one (a Diploneis sp.) which was the only one like it on the slide, for further imaging. I think this could be D. finnica, although I am not sure. 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. 34 images stacked in Zerene (Pmax).