In Vallisneria

Vallisneria is epihydrophilous. Therefore, pollination occurs on water surface. In Vallisneria, the female flower reachs the surface of water by the long stalk and the male flowers or pollen grains are released on to the surface of water. They are carried passively by water currents and some of them eventually reach the female flowers and the stigma to effect pollination. Fertilisation takes place in the water.