THE MORPHOLOGY AND TAXONOMY OF THE CENTRIC DIATOM GENUSPARALIA.I.PARALIA SIBERICACOMB. NOV.

Abstract
Paralia sulcata (Ehrenb.) Cleve is confirmed as the correct name for the type species of Paralia. This species is distinguished from another fossil species, Paralia siberica (A. Schmidt) Crawford & Sims, comb. nov. which has two varieties, P. siberica var. siberica and P. siberica var. laevis Crawford, nom.nov. This species and its two varieties are described.