Hydrophily is a fairly uncommon form of pollination whereby pollen is distributed by the flow of waters, particularly in rivers and streams. Hydrophilous species fall into two categories: those that distribute their pollen to the surface of water, and those that distribute it beneath the surface. Surface pollination is rare, and appears to be a transitional phase between wind pollination and true hydrophily, where pollen is completely submerged. Surface hydrophily has been observed in several… (More on Hydrophily)