Passage 8.19.2
τὰ δὲ μάλιστα ἥκοντα ἐς μνήμην Διονύσου ἐστὶν ἐνταῦθα ἱερόν, καὶ ἑορτὴν ὥρᾳ ἄγουσι χειμῶνος, ἐν ᾗ λίπα ἀληλιμμένοι ἄνδρες ἐξ ἀγέλης βοῶν ταῦρον, ὃν ἄν σφισιν ἐπὶ νοῦν αὐτὸς ὁ θεὸς ποιήσῃ, ἀράμενοι κομίζουσι πρὸς τὸ ἱερόν. θυσία μὲν τοιαύτη σφίσι καθέστηκε· πηγὴ δέ ἐστιν αὐτόθι ὕδατος ψυχροῦ, δύο μάλιστα ἀπὸ τοῦ ἄστεως ἀπωτέρω σταδίοις, καὶ ὑπὲρ αὐτῆς πλάτανος πεφυκυῖα.
The most notable thing there connected with Dionysus is a sanctuary, and they hold a festival in the season of winter. During this, men, having been smeared with fat, lift up a bull from the herd—whichever one the god himself guides them to choose—and carry it to the temple. Such is their established sacrifice. At the same place there is a spring of cold water, about two stades distant from the city, and above it grows a plane tree.