Passage 1.40.1
ἔστι δὲ ἐν τῇ πόλει κρήνη, ἥν σφισιν ᾠκοδόμησε Θεαγένης, οὗ καὶ πρότερον τούτων ἐπεμνήσθην θυγατέρα αὐτὸν συνοικίσαι Κύλωνι Ἀθηναίῳ. οὗτος ὁ Θεαγένης τυραννήσας ᾠκοδόμησε τὴν κρήνην μεγέθους ἕνεκα καὶ κόσμου καὶ ἐς τὸ πλῆθος τῶν κιόνων θέας ἀξίαν· καὶ ὕδωρ ἐς αὐτὴν ῥεῖ καλούμενον Σιθνίδων νυμφῶν. τὰς δὲ Σιθνίδας νύμφας λέγουσι Μεγαρεῖς εἶναι μέν σφισιν ἐπιχωρίας, μιᾷ δὲ αὐτῶν θυγατρὶ συγγενέσθαι Δία, Μέγαρόν τε παῖδα ὄντα Διὸς καὶ ταύτης δὴ τῆς νύμφης ἐκφυγεῖν τὴν ἐπὶ Δευκαλίωνός ποτε ἐπομβρίαν, ἐκφυγεῖν δὲ πρὸς τὰ ἄκρα τῆς Γερανίας, οὐκ ἔχοντός πω τοῦ ὄρους τὸ ὄνομα τοῦτο, ἀλλὰ ---νήχεσθαι γὰρ πετομένων γεράνων πρὸς τὴν βοὴν τῶν ὀρνίθων αὐτόν---διὰ τοῦτο Γερανίαν τὸ ὄρος ὀνομασθῆναι.
There is in the city a fountain, built for them by Theagenes, whom I previously mentioned as having married his daughter to Cylon the Athenian. This Theagenes, while ruling as a tyrant, constructed the fountain of such great size and splendour, and with such numerous pillars, that it is worthy of being seen. Into it flows water called by the name of the nymphs Sithnides. The Megarians say that these Sithnian nymphs are local to their land, and that Zeus once lay with one of their daughters, and that Megaros, the child born of Zeus and this nymph, escaped the floods in the age of Deucalion by fleeing to the heights of Geraneia. At that time, the mountain did not yet have that name, but—it is said—he was guided by the cries of cranes flying above, and thus from these birds it came to be named Geraneia.