Aquatic plants with floating leaves: Lemna spp., Hydrochcrris Morsus-ranae, Castalia (Nympliaea) alba.
DUCKWEED, the common botanical name for species of Lemna which form a green coating on fresh-water ponds and ditches.
The order Lemnaceae to which they belong 1, Lemna minor (Lesser Duckstamen, and a female flower, weed) nat.
It is represented in Britain by four species of Lemna, and a still smaller and simpler plant, Wolfa, in which the fronds are only one-twentieth of an inch long and have no roots.
73) and in Lemna; the dehiscence is then transverse.