Pollination achieved by wind is known as anemophily. Wind-pollinated plants do not invest in resources that attract pollinating organisms, such as nectar and scent. Instead, they produce dry and very small sized pollen grains and are in very large quantities so that they can be carried by the wind easily. Female structures on wind-pollinated plants are adapted to capture the passing pollen from the air. In Vallisneria pollination is achieved through hydrophily. In sea-grasses, the female flowers are submerged in water and the pollen grains are released inside the water.