MERCURY (MERcuRIus), in Roman mythology, the god of merchandise ( merx ) and merchants; later identified with the Greek Hermes. His nature is more intelligible and simple than that of any other Roman deity. In the native Italian states no trade existed till the influence of the Greek colonies on the coast introduced Greek customs and terminology. It was no doubt under the rule of the Tarquins that merchants began to ply their trade. Doubtless the merchants practised their religious ceremonies from the first, but their god Mercurius was not officially recognized by the state till the year 495 B.C. Rome frequently suffered from scarcity of grain during the unsettled times that followed the expulsion of the Tarquins. Various religious innovations were made to propitiate the gods; in 496 the Greek worship of Demeter, Dionysus and Persephone was established in the city, and in 495 the Greek god Hermes was introduced into Rome under the Italian name of Mercurius (Livy ii. 21, 27), as protector of the grain trade, especially with Sicily. Preller thinks that at the same time the trade in grain was regulated by law and a regular college or gild of merchants instituted. This college was under the protection of the god; its annual festival was on the 15th (the ides) of May, on which day the temple of the god had been dedicated at the southern end of the Circus Maximus, near the Aventine; and the members were called mercuriales as well as mercatores. Mommsen, however, considers the mercuriales to be a purely local gild - the pagani of the Circus valley. The 15th of May was chosen as the feast of Mercury, obviously because Maia was the mother of Hermes, that is of Mercury; and she was worshipped along with her son by the mercuriales on this day. According to Preller, this religious foundation had a political object; it established on a legitimate and sure basis the trade between Rome and the Greek colonies of the coast, whereas formerly this trade had been exposed to the capricious interference of government officials. Like all borrowed religions in Rome, it must have retained the rites and the terminology of its Greek original (Festus p. 257). Mercury became the god, not only of the mercatores and of the grain trade, but of buying and selling in general; and it appears that, at least in the streets where shops were common, little chapels and images of the god were erected. There was a spring dedicated to Mercury between his temple and the Porta Capena; every shopman drew water from this spring on the 15th of May, and sprinkled it with a laurel twig over his head and over his goods, at the same time entreating Mercury to remove from his head and his goods the guilt of all his deceits (Ovid, Fasti, v. 673 seq.). The word mercuriales was popularly used as equivalent to "cheat." Roman statuettes of bronze, in which Mercury is represented, like the Greek Hermes, standing holding the caduceus or staff in the one hand and a purse in the other (an element very rare in purely Hellenic representations), are exceedingly common.