CASTOR  and

POLLUX (Gr . HoXvSthKns), in Greek and Roman mythology, the twin sons of Leda, and brothers of Helen and Clytaemnestra . They were also known under the name of Dioscuri (&&rlcopom, later OebcKovpoe, children of Zeus), for, according to later tradition, they were the children of Zeus and Leda, whose love the god had won under the form of a swan . In some versions Leda is represented as having brought forth two eggs, from one of which were born Castor and Pollux, from the other Helen . In another account, Zeus is the father of Pollux and Helen, Tyndareus (king of Sparta) of Castor and Clytaemnestra . In Homer, Castor, Pollux and Clytaemnestra are said to be the children of Tyndareus and Leda, Helen the daughter of Leda by Zeus . The Dioscuri were specially reverenced among people of Dorian race, and were said to have reigned at Sparta, where also they were buried . They were also worshipped, especially in Athens, as lords and protectors (Entices, et vaKres) . Sailors in a storm prayed to them (Horace, Odes, i . 3) and sacrificed a white lamb, whereupon they were wont to appear in the form of fire at the masthead (probably referring to the phenomenon of St Elmo's fire), and the storm ceased . Later, they were confounded with the Samothracian Cabeiri . In battle they appeared riding on white horses and gave victory to the side they favoured .

They were the patrons of hospitality, and founded the sacred festival called Theoxenia . Ir They presided over public

games, Castor especially as the horse-tamer, Pollux as the boxer; but both are represented as riding on horseback or driving in a chariot . In Sparta their ancient symbol was two parallel beams (Soxava), connected by cross-bars, which the Spartans took with them into the field (Plutarch, De Fraterno Amore, 1; Herodotus v . 75); later, they were represented by two amphorae with snakes twined round them . Their most important exploits were the invasion of Attica, to rescue their sister Helen from Theseus; their share in the hunting of the Calydonian boar (see MELEAGER) and the Argonautic expedition, and their battle with the sons of Aphareus, brought about by a quarrel in regard to some cattle, in which Castor, the mortal (as the son of Tyndareus), fell by the hand of Idas . Pollux, finding him dead after the battle, implored Zeus to be allowed to die with him; this being impossible by reason of his immortality, Pollux was permitted to spend alternately one day among the gods, the other in Hades with his brother . According to another fable, the god marked his approval of their love by placing them together in the sky, as the Twins or the morning and evening star (Hyginus, Poet . Astronom. ii . 22) . Like the Asvins of the Veda, the bringers of light in the morning sky, with whom they have been identified, the Dioscuri are represented as youthful horsemen, naked or wearing only a light chlamys . Their characteristic attribute is a pointed egg-shaped cap, surmounted by a star . Though their worship was perhaps most carefully observed among people of Dorian origin, Castor and Pollux were held in no small veneration at Rome .

It was the popular belief in that

city from an early period that the battle of Lake Regillus had been decided by their interposition (Dion . Halic. vi . 13) . They had fought, it was said, armed and mounted, at the head of the legions of the commonwealth, and had afterwards carried the news of the victory with incredible speed to the city . The well in the Forum at which they alighted was pointed out, and near it rose their ancient temple, in which the senate often held its sittings . On the 15th of July, the supposed anniversary of the battle, a great festival with sumptuous sacrifices was celebrated in their honour, and a solemn parade of the Roman knights (transvectio equitum), who looked upon the Dioscuri as . their patrons, took place . (Apollodorus iii. to . 7, it . 2; Homer, Odyssey, xi . 299; Hyginus, Fab . 77 . 155; Pindar, Nem. x .

6o, 8o and schol.; Diod . Sic. iv . 43; Plutarch, Theseus, 32, 33;

Theocritus, Idyll, xxii.) See Maurice Albert, Le Culte de Castor et Pollux en Italie (1883), with special descriptions and representations in art, on coins, vases and statues; S . Eitrem, " Die gottlichen Zwillinge bei den Griechen (treating of the divine beings mentioned in pairs in Greek mythology), in Videnskabs-Selskab Skrifter (Christiania, 1902) ; W . R . Paton, De Cultu Dioscurorum apud Graecos (Bonn, 1894); L . Myriantheus, Arcvins oder arische Dioskuren (Munich, 1876); J . R . Harris, The Dioscuri in the Christian Legends (1903), and The Cult of the Heavenly Twins (1906); W . Helbig, " Die Castores als Schutzgotter des romischen Equitatus," in Hermes, xl . (1905); C . Jaisle, Die Dioskuren als Reiter zur See bei Griechen and Romern, and ihr Fortleben in christlichen Legenden (Tubingen, 19o7); L .

Preller, Griechische and romische Mythologie; articles by A . Furtwangler in Roscher's Lexikon der Mythologie, and by M . Albert in Daremberg and Saglio's Dictionnaire des antiquites .