Review

There has not been an extensive taxonomical treatment of the Lemnaceae since the publication of the famous works of Hegelmaier (1868, 1895). As the quantity of preserved and dried material of this family has increased considerably since Hegelmaier’s time, and as some new species have been described and the flowers and fruits of some other species have become known, there is, according to Daubs, a ’need for a critical review of the family in the light of this later knowledge, as well as some synthesis of the widely scattered data into a more readily available form’. I have used this revision and it must at once be praised for the clear and adequate descriptions of the taxa and the excellent, accurate drawings.