Van Geel et al. 1981: Ellipsoidal Spirogyra spores 80-90 X 44-52 μm. Walt about 1.5-2 μm thick, with pits 2.5 μm wide and 3-4 μm apart. Most of the spores burst open along a meridional suture.
van Geel B, Bohncke SJP, Dee H (1981) A palaecological study of an upper Late Glacial and Holocene sequence from 'De Borchert', The Netherlands. Rev. Palaeobot. Palynol. 31:367-448.