E. Cobham Brewer 18101897. Dictionary of Phrase and Fable. 1898.
Scylla,
daughter of Nisus, promised to deliver Megara into the hands of Minos. To redeem this promise she had to cut off a golden hair on her fathers head, which she effected while he was asleep. Minos, her lover, despised her for this treachery, and Scylla threw herself from a rock into the sea. At death she was changed into a lark, and Nisus into a hawk. Scylla turned into a rock by Circe has no connection with the daughter of Nisus.