The symbolism of the double serpent and the "guardian of the treasure"

Within the vast mythical corpus concerning the ophidic symbolism there are some mythologems, recurring all over the world, conveying certain initiatory knowledge whose universality goes beyond the spatial and chronological boundaries, such as that of the double serpent (Caduceus of Mercury, Iga and Pingala), that of the serpent who, standing beneath the worlds or surrounding the earth in the form of Ouroboros, holds the entire cosmic manifestation, and that of the dragon in the function of "Guardian of the treasure" that the hero must subdue and defeat in order to save the "Princess ".