The Histories · 4.105

The Neuroi practise the Scythian customs: and one generation before the expedition of Dareios it so befell them that they were forced to quit their land altogether by reason of serpents: for their land produced serpents in vast numbers, and they fell upon them in still larger numbers from the desert country above their borders; until at last being hard pressed they left their own land and settled among the Budinoi. These men it would seem are wizards; for it is said of them by the Scythians and by the Hellenes who are settled in the Scythian land that once in every year each of the Neuroi becomes a wolf for a few days and then returns again to his original form. For my part I do not believe them when they say this, but they say it nevertheless, and swear it moreover.

Herodotus of Halicarnassus · trans. G. C. Macaulay, 1890
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