Drawing

Опис:

Distephanus octangulatus Wailes, 1931. Silicieous skeleton consisting of a frame forming a truncated cone, the basal ring octagonal with an external projection at each angle, from the centers of four sides arise supporting bars attached to the angles of the square apical ring, the side openings provided with small semicircular projections at the centers of the longer sides. Diameter of basal ring 35 microns