Passage 2.13.8
λέγεται δὲ καὶ ὧδε ὑπὸ Φλιασίων λόγος· Ἡρακλέα, ὅτʼ ἐκ Λιβύης ἀνεσώθη κομίζων τὰ μῆλα τὰ Ἑσπερίδων καλούμενα, ἐς Φλιοῦντα ἐλθεῖν κατὰ δή τι ἴδιον, διαιτωμένου δὲ ἐνταῦθα Οἰνέα ἐξ Αἰτωλίας ἀφικέσθαι παρʼ αὐτόν· ἐγεγόνει δὲ τῷ Ἡρακλεῖ πρότερον ἔτι κηδεστής, τότε δὲ ἀφιγμένος εἱστία τὸν Ἡρακλέα ἢ αὐτὸς εἱστιᾶτο ὑπὸ ἐκείνου. Κύαθον δʼ οὖν παῖδα οἰνοχόον Οἰνέως οὐκ ἀρεσθεὶς τῷ δοθέντι πώματι παίει τῶν δακτύλων ἑνὶ ἐς τὴν κεφαλήν· ἀποθανόντος δὲ αὐτίκα ὑπὸ τῆς πληγῆς Φλιασίοις ἐστὶν οἴκημα ἐς μνήμην. τοῦτο ᾠκοδόμηται μὲν παρὰ τὸ ἱερὸν τοῦ Ἀπόλλωνος, ἀγάλματα δὲ λίθου πεποιημένα ἔχει, κύλικα ὀρέγοντα Ἡρακλεῖ τὸν Κύαθον.
The Phliasians tell the following story as well: Heracles, when he returned from Libya bringing the so-called apples of the Hesperides, reached Phlius for some private reason. While he was staying there, Oeneus journeyed from Aetolia to see him. Oeneus had been related by marriage to Heracles before, and upon arriving at that time he entertained Heracles or himself was entertained by him. Now Cyathus, the son of Oeneus, who was serving wine, did not please Heracles with the drink he offered; and Heracles struck him on the head with one finger. Cyathus instantly died from the blow, and the Phliasians built a chapel in remembrance of the incident. This structure stands beside the sanctuary of Apollo, and inside it are stone statues portraying Cyathus offering a cup to Heracles.