Passage 9.37.5
λέγεται δὲ ὁ Τροφώνιος Ἀπόλλωνος εἶναι καὶ οὐκ Ἐργίνου· καὶ ἐγώ τε πείθομαι καὶ ὅστις παρὰ Τροφώνιον ἦλθε δὴ μαντευσόμενος. τούτους φασίν, ὡς ηὐξήθησαν, γενέσθαι δεινοὺς θεοῖς τε ἱερὰ κατασκευάσασθαι καὶ βασίλεια ἀνθρώποις· καὶ γὰρ τῷ Ἀπόλλωνι τὸν ναὸν ᾠκοδόμησαν τὸν ἐν Δελφοῖς καὶ Ὑριεῖ τὸν θησαυρόν. ἐποίησαν δὲ ἐνταῦθα τῶν λίθων ἕνα εἶναί σφισιν ἀφαιρεῖν κατὰ τὸ ἐκτός· καὶ οἱ μὲν ἀεί τι ἀπὸ τῶν τιθεμένων ἐλάμβανον· Ὑριεὺς δὲ εἴχετο ἀφασίᾳ, κλεῖς μὲν καὶ σημεῖα τὰ ἄλλα ὁρῶν ἀκίνητα, τὸν δὲ ἀριθμὸν ἀεὶ τῶν χρημάτων ἐλάττονα.
It is said that Trophonius was a son of Apollo and not of Erginus; I myself am persuaded of this, and likewise any man who has come before Trophonius for prophecy. They say these brothers became remarkable when fully grown, both for constructing temples for the gods and royal palaces for men. For they built Apollo's temple at Delphi and the treasury for Hyrieus. There they arranged one of the outer stones in such a way that they could remove it easily. Thus they kept taking some of the offering secretly. Hyrieus was baffled, for although he saw the locks and other seals untouched, the amount of treasure was always found diminished.