FIGURE 2 in Morphological features of Late Ordovician (Sandbian) bryozoans from the basin of Khrevitsa River (north-western Russia) and description of a new species of the genus Prophyllodictya Gorjunova, 1987

FIGURE 2. The composite scheme of the Upper Ordovician in the Leningrad region, including strata eroded before the Devonian (biozones after Suyarkova & Koren' 2009; age dates after Gradstein et al. 2020)