Passage 10.7.8
παγκράτιον δʼ ἐν παισὶ καὶ συνωρίδα τε πώλων καὶ πῶλον κέλητα πολλοῖς ἔτεσιν ὕστερον κατεδέξαντο Ἠλείων, τὸ μὲν πρώτῃ πυθιάδι ἐπὶ ταῖς ἑξήκοντα, καὶ Ἰολαΐδας ἐνίκα Θηβαῖος· διαλιπόντες δὲ ἀπὸ ταύτης μίαν κέλητι ἔθεσαν δρόμον πώλῳ, ἐνάτῃ δὲ ἐπὶ ταῖς ἑξήκοντα συνωρίδι πωλικῇ, καὶ ἐπὶ μὲν τῷ πώλῳ τῷ κέλητι Λυκόρμας ἀνηγορεύθη Λαρισαῖος, Πτολεμαῖος δὲ ἐπὶ τῇ συνωρίδι Μακεδών· ἔχαιρον γὰρ δὴ Μακεδόνες οἱ ἐν Αἰγύπτῳ καλούμενοι βασιλεῖς, καθάπερ γε ἦσαν. δάφνης δὲ στέφανος ἐπὶ τῶν Πυθίων τῇ νίκῃ κατʼ ἄλλο μὲν ἐμοὶ δοκεῖν ἐστιν οὐδέν, ὅτι δὲ τῆς Λάδωνος θυγατρὸς Ἀπόλλωνα ἐρασθῆναι κατέσχηκεν ἡ φήμη.
The Eleans admitted the boys' pancratium and later, by many years, the race for two-horse chariots of colts and the riding-race for colts—the first of these contests at the sixty-first Pythian festival, when Iolaïdas of Thebes won. After an interval of one festival from this, they set up a riding-race for colts, and at the sixty-ninth festival the chariot-race for a pair of colts. In the riding-match for colts, Lyformas of Larissa was proclaimed victor, and Ptolemy the Macedonian in the pair of colt-chariots; for the Macedonian kings in Egypt, as they were then called, had a passion for such victories, since indeed they were actual Macedonians. As for why the crown at the Pythian games is of laurel, in my opinion there is no other reason except the tradition that Apollo fell in love with the daughter of Ladon.