Clytemnestra, in Grecian legends, the daughter of Tyndarus, king of Sparta, and Leda. After her seduction by Jupiter, Leda, metamorphosed into a swan, is fabled to have laid two eggs, from one of which were produced Pollux and Helen, said to be the children of Jupiter, and from the other Castor and Clytemnestra, children of Tyndarus. Clytemnestra was given in marriage by her father to Agamemnon, and her sister Helen to Menelaus, both sons of Atreus, king of Mycena3; the former of whom succeeded his own father on his throne, while the latter succeeded his father-in-law on that of Sparta. During the absence of Agamemnon in the war against Troy growing out of the abduction of Helen, Clytemnestra lived in adultery with AEgisthus. On her husband's return she slew him in a bath, and also his paramour Cassandra, in alleged retribution for the loss of her daughter Iphigenia. Clytemnestra and AEgis-thus were afterward in their turn slain by Orestes, son of Agamemnon. The story of Clytemnestra has been a popular theme with dramatists; among those who have used it are Voltaire in Oreste, and Soumet in Clytemnes-tre. It is also the subject of one of Pierre Guerin's finest pictures.