Among personifications, _Helios_ is a youthful figure in a chariot, usually with rays round his head (as on Plate LIII.); in one or two cases his head is surmounted by a white disc; _Selene_ appears on horseback, and is sometimes indicated by a crescent moon; where Helios is accompanied by a goddess in a chariot, it is probable that _Nyx_ (Night) is intended (see p. 79). The _Stars_ are represented as nude youths. The _Aurae_ or breezes appear as girls floating through the air; the _Hyades_ or rain-Nymphs are identified by their water-pitchers. A group of winged gods and goddesses is formed by Eos, Agon (the masculine counterpart of Nike), Eris, Lyssa (Frenzy),[1957] and the various wind-gods, such as Boreas and Zephyros. These are found at all periods, but the types vary. _Eris_, who is only found on B.F. vases, resembles the Gorgons (see below), a somewhat grotesque figure with wings, rough hair, and short girt chiton; _Lyssa_ only occurs on Apulian vases, and is akin in type to the Furies—in two instances her figure is enclosed in a circle of rays of light, perhaps to express the blinding effect of her action, and she holds a goad.[1958] _Oistros_, a kindred figure, rides in a car drawn by serpents, and carries torches. The type of Agon is assimilated to that of Eros on R.F. vases; on those of earlier date (if this is the correct interpretation) he wears a short girt chiton and holds a wreath. The _Wind-gods_ on B.F. vases wear the petasos and high boots, and short girt chiton; _Zephyros_ is represented as a youth; and _Boreas_, who only occurs on R.F. vases, wears Thracian costume; he is bearded, and his hair is often rough and shaggy. But these winged deities cannot always be identified with certainty. Among other personifications, _Geras_ is a somewhat ugly old man; the _Muses_ are distinguished by their various musical instruments; and _Cities and Countries_ are occasionally individualised. For instance, Thebes, on a vase by Assteas, wears a turreted crown; Sparta appears as a Nymph on horseback; and, generally speaking, their presence is usually indicated not only by inscriptions, but by their relation to the scene depicted.[1959] _River-gods_, such as Acheloös, appear as human-headed bulls, with horns, but the last-named on a stamnos by Pamphaios (E 437 in B.M.) has a fish-tail.