But on her return, Galatea changes her dead lover into the spirit of the Sicilian river Acis. That the story sometimes had a more successful outcome for Polyphemus is also attested in the arts. In one of the murals rescued from the site of Pompeii, Polyphemus is pictured seated on a rock with a cithara (rather than a syrinx) by his side, holding out a hand to receive a love letter from Galatea, which is carried by a winged Cupid riding on a dolphin. In another fresco, also dating from the 1st century AD, the two stand locked in a naked embrace (see below). From their union came the ancestors of various wild and war-like races. According to some accounts, the Celts (Galati in Latin, Γάλλοi in Greek) were descended from their son Galatos, while Appian credited them with three children, Celtus, Illyrius and Galas, from whom descend the Celts, the Illyrians and the Gauls respectively. There are indications that Polyphemus’ courtship also had a more successful outcome in one of the dialogues of Lucian of Samosata. There Doris, one of Galatea's sisters, spitefully congratulates her on her love conquest and she defends Polyphemus. From the conversation, one understands that Doris is chiefly jealous that her sister has a lover. Galatea admits that she does not love Polyphemus but is pleased to have been chosen by him in preference to all her companions. That their conjunction was fruitful is also implied in a later Greek epic from the turn of the 5th century AD. In the course of his "Dionysiaca", Nonnus gives an account of the wedding of Poseidon and Beroe, at which the Nereid "Galatea twangled a marriage dance and restlessly twirled in capering step, and she sang the marriage verses, for she had learnt well how to sing, being taught by Polyphemos with a shepherd’s syrinx." During Renaissance and Baroque times Ovid's story emerged again as a popular theme. In Spain Luis de Góngora y Argote wrote the much admired narrative poem, "Fábula de Polifemo y Galatea", published in 1627. It is particularly noted for its depiction of landscape and for the sensual description of the love of Acis and Galatea.