Caduceus is a continuation of the older Indo-European dragon-slayer motif. Wilhelm Heinrich Roscher (1913) pointed out that the serpent as an attribute of both Hermes and Asclepius is a variant of the "pre-historic semi-chthonic serpent hero known at Delphi as Python", who in classical mythology is slain by Apollo. One Greek myth of origin of the caduceus is part of the story of Tiresias, who found two snakes copulating and killed the female with his staff. Tiresias was immediately turned into a woman, and so remained until he was able to repeat the act with the male snake seven years later.
Snake worship fresh water, and punished lawbreakers. The Aborigines in southwest Australia called the serpent the Waugyl, while the Warramunga of the east coast worshipped the mythical Wollunqua. Serpent worship was well known in ancient Europe. The Roman genius loci took the form of a serpent. In Italy, the Marsian goddess Angitia, whose name derives from the word for "serpent," was associated with witches, snakes, and snake-charmers. Angitia is believed to have also been a goddess of healing. Her worship was centered in the Central Apennine region. A snake was kept and fed with milk during rites dedicated to Potrimpus, a Prussian