Ceratophyllum L.
Lvs in whorls of 3-10, finely dichotomously forked. Fls unisexual, solitary in lf axils. Perianth a single whorl; segments 8-12. Stamens numerous. Carpel solitary; ovule 1.
c. 30 spp., cosmopolitan. Naturalised sp. 1.
