Cytological studies on lemanea fluviatilis l. In the river usk

Abstract

Seasonal studies of nuclear phases in clonal and naturally occurring plants of Lemanea fluviatilis L. in the River Usk have shown that N= 18-19 and 27V= 36-38.Carposporophytes, carpospores, the Chantransia-stage and lower cells of gametophyte thalli arising from the latter were all diploid. Meiosis occurred in the apical cells of the gameto- phytes and in some short, non-sporing gonimoblast branches, particularly induced during periods of low water temperatures. The advantages of using easily transportable rock units for such studies are discussed. © 1982 British Phycological Society.