Passage 3.12.2
δοκεῖν δʼ ἐμοὶ δρόμου Ἰκάριος τὸ ἀγώνισμα ἐποίησε μιμούμενος Δαναόν. Δαναῷ γὰρ τοῦτο ἐπὶ ταῖς θυγατράσιν εὑρέθη, καὶ ὡς γυναῖκα οὐδεὶς ἤθελεν ἐξ αὐτῶν διὰ τὸ μίασμα ἀγαγέσθαι, διέπεμπε δὴ ὁ Δαναὸς ἕδνων ἄνευ δώσειν ᾗ ἂν ἕκαστος κατὰ κάλλος ἀρέσκηται· ἀφικομένοις δὲ ἀνδράσιν οὐ πολλοῖς ἀγῶνα δρόμου κατέστησε, καὶ πρώτῳ τε ἐλθόντι ἐγένετο ἑλέσθαι πρώτῳ τῶν ἄλλων καὶ μετʼ ἐκεῖνον τῷ δευτέρῳ καὶ ἤδη κατὰ τὰ αὐτὰ ἄχρι τοῦ τελευταίου· τὰς δὲ ὑπολειφθείσας μένειν ἔφοδον ἄλλην μνηστήρων ἔδει καὶ ἀγῶνα ἄλλον δρόμου.
It seems to me that Icarius established the footrace contest in imitation of Danaus. For this device was originally devised by Danaus concerning his daughters: when no one wished to marry any of them because of their pollution, Danaus made it known far and wide that he would give away without dowry whichever daughter each suitor approved of according to her beauty. When a small number of suitors arrived, he set a running contest for them. The man who finished first was the first allowed to choose among the maidens, and after him the second, and thereafter each similarly until the last competitor. Those daughters left unmarried had to wait for another company of suitors and another footrace competition.