Jacobus de Voragine
The "Acts of Saint Elmo" were partly compiled from legends that confuse him with a Syrian bishop Erasmus of Antioch. Jacobus de Voragine in the "Golden Legend" credited him as a bishop at Formia over all the Italian Campania, as a hermit on Mount Lebanon, and a martyr in the persecutions under Eastern Roman Emperor Diocletian. There appears to be no historical basis for his "passio".