"[Plin. Nat. 25.12.] - THE PANACES HERACLEON: THREE REMEDIES.
A second kind of panaces is known by the name of “heracleon,” from the fact that it was first discovered by Hercules. Some persons, however, call it “Heracleotic origanum,” or wild origanum, from its strong resemblance to the origanum of which we have already spoken: the root of it is good for nothing.”
(The Natural History. Pliny the Elder. John Bostock, M.D., F.R.S. H.T. Riley, Esq., B.A. London. Taylor and Francis, Red Lion Court, Fleet Street. 1855.)