Two examples of Aulacodiscus compactus from Palos Verdes, California, USA. Fossil marine material. W.D.F. 340. Sty.Aro. (Styrax Aroclor) mountant, and dated October 1968. Both dip downwards towards the left. Prepared by ECP Bone. 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. 38 images stacked in Zerene (Pmax).
Aulacodiscus compactus Rattray 1888. Published in: Rattray, J. (1888). A revision of the genus Aulacodiscus Ehrb. Journal of the Royal Microscopical Society 8(3): 337-382, 3 pls [V-VII]. Page 354, Plate V (5), Figure 8.