Passage 8.46.4
Κυζικηνοί τε, ἀναγκάσαντες πολέμῳ Προκοννησίους γενέσθαι σφίσι συνοίκους, Μητρὸς Δινδυμήνης ἄγαλμα ἔλαβον ἐκ Προκοννήσου· τὸ δὲ ἄγαλμά ἐστι χρυσοῦ, καὶ αὐτοῦ τὸ πρόσωπον ἀντὶ ἐλέφαντος ἵππων τῶν ποταμίων ὀδόντες εἰσὶν εἰργασμένοι. βασιλεὺς μὲν δὴ Αὔγουστος καθεστηκότα ἐκ παλαιοῦ καὶ ὑπό τε Ἑλλήνων νομιζόμενα καὶ βαρβάρων εἰργάσατο· Ῥωμαίοις δὲ τῆς Ἀθηνᾶς τὸ ἄγαλμα τῆς Ἀλέας ἐς τὴν ἀγορὰν τὴν ὑπὸ Αὐγούστου ποιηθεῖσαν, ἐς ταύτην ἐστὶν ἰόντι.
The Cyzicenes, having compelled the Proconnesians by war to combine and live with them, took from Proconnesus the statue of Mother Dindymene. The statue is made of gold, and its face, instead of ivory, is fashioned from the teeth of river horses. Augustus, after becoming emperor, made regular the rites that had existed from ancient times, observed both by Greeks and barbarians. As for the Romans, the statue of Athena Alea stands in the marketplace which was constructed by Augustus; one encounters it upon entering this marketplace.