Obv.: Postumus radiate head r., IMP C POSTVMVS P F AVG
Rev.: Aesculapius the god of medicine, son of Apollo, standing facing head left with his serpent-twined staff (often misdescribed as a caduceus), globe at feet to r., SALVS AVG
As Cowley hints (in Plantarum 1.137-38) the serpent not unlike like archer Apollo can stand for both poison and antidote (cf. our own "snake-oil"); serpents shedding their skins also stand for renewal and vitality. Salus ("Health"), Aesculapius' daughter, commonly depicted feeding a snake, also featured on Roman Imperial coins tying emperors' well-being to the commonwealth's.