Passage 4.31.4
ἰόντι δὲ ἐκ Θουρίας ὡς ἐπὶ Ἀρκαδίας εἰσὶν αἱ πηγαὶ τοῦ Παμίσου· καὶ ἐπʼ αὐταῖς παισὶ μικροῖς ἀκέσματα γίνεται. ἰοῦσι δὲ ἀπὸ τῶν πηγῶν ἐν ἀριστερᾷ καὶ προελθόντι ὡς τεσσαράκοντα στάδια, ἔστι Μεσσηνίοις ἡ ὑπὸ τῇ Ἰθώμῃ πόλις· περιέχεται δὲ οὐ τῇ Ἰθώμῃ μόνον ἀλλὰ καὶ ἐπὶ τὸν Πάμισον τὰ τετραμμένα ὑπὸ τῆς Εὔας· τὸ δὲ ὄνομα γενέσθαι τῷ ὄρει φασὶ Βακχικόν τι ἐπίφθεγμα εὐοῖ Διονύσου πρῶτον ἐνταῦθα αὐτοῦ τε εἰπόντος καὶ τῶν ὁμοῦ τῷ Διονύσῳ γυναικῶν.
On the way from Thouria towards Arcadia are the springs of the river Pamisos; and at these springs cures are performed for young children. Proceeding from the springs, after advancing about forty stadia, you come to the city of the Messenians beneath Ithome. The city is encompassed not only by Mount Ithome itself, but also by an area facing toward the Pamisos beneath Mount Eva. They say this mountain (Eva) received its name from the Bacchic cry "evoi," first uttered here by Dionysus himself and the women who accompanied him.