Diatoms Paralia sulcata var. biseriata Grunow 1884
(or Paralia grunowii Gleser 1992).
Diatomites from Nikolsk, Russia. Paleocene, Danian Stage (61,6-66,0 million years).
Objective PlanApochromat HI 60x/1,0 (Labor-microscopes, Russland)

1 Foto

stacking of 13 foto