Glaucus

Glaucus (Ancient Greek: Γλαῦκος) was a Greek prophetic sea-god, born mortal and turned immortal upon eating a magical herb. It was believed that he commonly came to the rescue of sailors and fishermen in storms, having once been one himself.

Glaucus' parentage is different in the different traditions, which Athenaeus lists:

The story of Glaucus' deification was dealt with in detail by Ovid in Metamorphoses and briefly referenced by many other authors. According to Ovid, Glaucus began his life as a mortal fisherman living in the Boeotian city of Anthedon. He discovered by accident a magical herb which could bring the fish he caught back to life, and decided to try eating it. The herb made him immortal, but also caused him to grow fins instead of arms and a fish's tail instead of legs (though some versions say he simply became a merman-like being), forcing him to dwell forever in the sea. Glaucus was initially upset by this side-effect, but Oceanus and Tethys received him well and he was quickly accepted among the deities of the sea, learning from them the art of prophecy.

John Tzetzes adds to the above story that Glaucus became "immortal, but not immune to aging".

In an alternate, non-extant version cited in Athenaeus (with reference to Nicander's Aetolian History), Glaucus chased a hare on mount Oreia until the animal fell down almost dead, then carried his prey to a spring and rubbed it with a bunch of grass that was growing about. The herb brought the hare back to life. Glaucus then tasted it himself and fell into a state of "divine madness", in which state Zeus made him fling himself into the stormy sea.

Athenaeus also informs that in yet another version followed by Possis of Magnesia, Glaucus (rather than Argus) was the builder and the pilot of Argo. During a naval battle between the Argonauts and the Etruscans, he fell into the sea and by the will of Zeus became a sea god.

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