Nereus represents the sea in its quiet state. […] A serpent with its tail in its mouth meant the year. […] He punished the raven for its garrulity by changing its color from white to black. […] Poseidon, or Neptune, presided over the sea in its relation to storms and earthquakes, in its relation to commerce, and as the source of vegetation on its shores. […] Each month and day had its own god.