Two examples of Arachnoidiscus indicus from Sendai, Japan. Prepared by WA Firth. Olympus BHB microscope using 450nm LED light. 20x Nikon Plan Apo NA 0.65 objective. Olympus Aplanat Achromat condenser, oblique lighting. 2.5x Nikon CF PL photoeyepiece. Monochrome converted Nikon d850 camera. 24 images stacked in Zerene (Pmax).
Arachnoidiscus indicus Ehrenberg 1854. Published in: Ehrenberg, C.G. (1854). Mikrogeologie. Einundvierzig Tafeln mit über viertausend grossentheils colorirten Figuren, Gezeichnet vom Verfasser. pp. [1]-31, 40 pls [Taf. I-XXXX]. Leipzig: Verlag von Leopold Voss. Plate 36, Figure 34.