The Diatom Genus Tabellaria: I. Taxonomy and Morphology

A morphological study of natural populations of Tabellaria infresh water suggested that there were two fundamentally differenttypes of growth (and therefore frustule structure) in the genus,and this has been confirmed by means of unialgal clone cultures.The existence of these different types of growth forms the basisfor a revision of the genus. A diagnosis of T. quadriseptatanov. spec, is given, the specific limits of T. fenestrata andT. flocculosa are redefined, and the occurrence of T. binalisin Britain is reported for the first time.