of the winning of a nymph to wife by a mortal man[1], so the myth, by which the exploit of bearing off wonderful fruit from the custody of a dragon was numbered among the labours of Heracles, is nothing more than the authorised version, so to speak, of a fairy-tale that might have been heard of winter-nights in Greek cottage-homes any time between the Pelasgian and the present age.
Daemons of the air, the fourth class of genius which we have to consider, have been acknowledged ever since the time of Hesiod and doubtless from a period far anterior to that. In his theology it was the lot of the first race of men in the golden age to become after death daemons 'clothed in air and going to and fro through all the world' as good guardians of mortal men. But the goodness which Hesiod attributes to the genii of the air was never, I suspect, an essential trait in their character. In Hesiod it is a corollary of the statement that they are the spirits of men who belonged to the golden age; but there is no reason to suppose that the common-folk ever regarded them as more beneficent than other gods and daemons. At any rate at the present day the (
Greek characters)[Greek: aerika], or genii of the air, are no better disposed towards mankind than any other supernatural beings.
Of this class as a whole little can be said. The word (Greek characters)[Greek: aeriko] is applied to almost any apparition too vague and transient to be more clearly defined. It suggests something 'clothed in air,' something less tangible, less discernible, than most of the beings whom the peasant recognises and fears. The limits of its usage are hard to fix. It may properly include a Nereid whose passing through the air is the whirlwind, and it will equally certainly exclude a callicantzaros or a dragon. Yet even the Nereids are more substantial than the genii of the air in their truest form; for the assaults of Nereids upon men and women are made, as we have seen, from without[2], while genii of the air are more often supposed to 'possess' men in the same way as do devils, and to be liable to exorcism.
But, if the class as a whole is too vague and shadowy in the popular imagination to be capable of exact description, one
