Description:
<em>Spirogyra occidentalis</em> (Transeau) Czurda 1932 and <em>S. scrobiculata</em> (Stockmayer) Czurda 1932, two species new in the Polish flora and S. pseudovarians Czurda 1930, a species only cited in literature, are described in samples collected in central Poland. The diagnosis of <em>S. occidentalis</em> and <em>S. pseudovarians</em> has been supplemented with measuring data of the inflated sterile cells in conjugation filaments. The figures show the hitherto unknown inflated sterile cells.