The 13th Sign of the Zodiac : Ophiuchus Serpent bearer.

The Astrological Lore of Ophiuchus: Ophiuchus was better known in classical times as Asclepius, [in Latin, Aesculapius] the God of Medicine. He learnt the art from Chiron, the Centaur. On either side of Ophiuchus in the heavens lie the two parts of the sign of the serpent he holds, Serpens Caput, the Serpent's Head and Serpens Cauda, the Serpent's Tail. The twined serpent staff is the badge of the medical profession to this day. [However, the sign of the serpent itself does not form part of the Real Solar Zodiac, though it does from part of the Planetary Zodiac.] It is from the Serpent that Ophiuchus learnt the secret of the Elixir of Life.
The even older Babylonian version is slightly different. Here the serpent is Tiamat, the Monster of the Bitter Ocean. Holding Tiamat is Marduk, the Sun God of the Babylonians. They are doing battle together in the eternal fight of good against evil.