ERYTHRAEUM MARE, erroneously called Rubrum by the Romans. Thus the ocean that washes Arabia and Persia, and extends a great way farther, is denominated. Hence it is, Herodotus says, that the Euphrates and Tigris fall into the Mare Erythreum. He also calls it the South Sea, on which the Persians dwell. It takes its name, not from its colour, the error of the Romans, who translated Erythreum, "Rubrum;" but from Erythras, son of Perseus and Andromeda, whose kingdom lay on the confines of that sea; whence its name Erythreum.