Sirens were another personification of the dangers of the sea: sea demons, half women and half birds, their father was the river-god Achelous and the mother the muse Melpomenes, or the muse Terpsichore. They are mentioned for the first time in the Odyssey , where they are two; later traditions mention them as being four, or, more often, three, called in the commonest tradition Ligia, Leucosia and Partenope, from which the ancient name of Naples . In the tradition they are very good musicians and, according to Apollodorus, one played the lyre, another one sang, the third held the flute.
According to the legend the island of the Sirens was located along the coast of southern Italy, off the peninsula of Sorrento ; with the charm of their music, they attracted the sailors who were passing nearby, the ships approached dangerously the rocky coast and were smashed, and the Sirens devoured the unwary.
According to the legend, the Argonauts passed near them, but Orpheus sang so melodiously, that the sailors of the ship Argo had no desire to listen. Only Bute dived into the sea but was saved by Aphrodite.
Also Ulysses sailed across their waters but, warned by Circe, he ordered his men to plug their ears with wax, and to tie him to the mast, and prohibited them to untie him, whatever petition he would have addressed to them. The story tells that the Sirens, upset by their failure to catch Ulysses, threw themselves into the sea and drowned.
About their origin and their hybrid appearance, the versions are different. Ovid says that they were originally ordinary women, but asked the gods the benefit of the wings, to search over the seas one of them kidnapped by Pluto . For others, they were transformed by Demeter as punishment for not opposing to the kidnapping of her daughter. Or that Aphrodite had deprived them of their beauty, because they disdained the pleasures of love.
In later legends were considered gods of the afterlife and for this reason they are often depicted on coffins.