Passage 9.39.3
καὶ ἔστι μὲν πρὸς τῇ ὄχθῃ τοῦ ποταμοῦ ναὸς Ἑρκύνης, ἐν δὲ αὐτῷ παρθένος χῆνα ἔχουσα ἐν ταῖς χερσίν· εἰσὶ δὲ ἐν τῷ σπηλαίῳ τοῦ ποταμοῦ τε αἱ πηγαὶ καὶ ἀγάλματα ὀρθά, περιειλιγμένοι δέ εἰσιν αὐτῶν τοῖς σκήπτροις δράκοντες. ταῦτα εἰκάσαι μὲν ἄν τις Ἀσκληπιοῦ τε εἶναι καὶ Ὑγείας, εἶεν δʼ ἂν Τροφώνιος καὶ Ἕρκυνα, ἐπεὶ μηδὲ τοὺς δράκοντας Ἀσκληπιοῦ μᾶλλον ἢ καὶ Τροφωνίου νομίζουσιν ἱεροὺς εἶναι. ἐπὶ δὲ τῷ ποταμῷ μνῆμά ἐστιν Ἀρκεσιλάου· Λήϊτον δὲ ἀνακομίσαι φασὶ τοῦ Ἀρκεσιλάου τὰ ὀστᾶ ἐκ Τροίας.
Beside the bank of the river there is a temple of Hercyna; within it stands a maiden holding a goose in her hands. In the cave are the springs of the river and upright statues, with serpents entwined around their scepters. One might suppose these images to represent Asclepius and Hygieia, but they may equally be Trophonius and Hercyna, since serpents are regarded as sacred not more to Asclepius than to Trophonius. Near the river there is a tomb of Arcesilaus; it is said that Leïtus brought back the bones of Arcesilaus from Troy.