Plate P3. Magnification for light micrography is 2200x. Light micrography: PH = phase-contrast light, PL = plain transmitted light, XP = cross-polarized light, SEM = scanning electron micrography. 15, 16. Prediscosphaera stoveri, Sample 173-1069A-12R-3, 134-136 cm, PH (15) and XP (16).