The Heliades were seven nymph daughters of the sun-god Helios. When their brother Phaethon was struck from the chariot of the sun by Zeus, they gathered around his smoky grave on the banks of the River Eridanos and in their unrelenting grief were transformed into poplar-trees and their tears into golden amber. Aeschylus and Ovid use the names of two of Homer's Neaerides for the poplar-tree sisters of Phaethon. However they were usually regarded as a distinct set of nymphs.