Mefitis

Face of the goddess Mefitis, bronze fragment stored in the Museo Archeologico Nazionale della Basilicata (National Archaeological Museum of Basilicata), Potenza.
Ancient Roman votive offering such as would have been offered to the goddess

In Roman mythology, Mefitis (or Mephitis; Mefite in Italian) was a minor goddess of the poisonous gases emitted from the ground in swamps and volcanic vapors.