Pausanias Analysis

ἔχει δὲ τὰς πηγὰς ὁ Ἐρύμανθος ἐν ὄρει Λαμπείᾳ, τὸ δὲ ὄρος τοῦτο ἱερὸν εἶναι Πανὸς λέγεται·

The first clause has Ἐρύμανθος as the subject of ἔχει and τὰς πηγὰς as its object; the second clause is a reported impersonal construction, with τὸ ὄρος τοῦτο as the accusative subject of εἶναι and Πανός as a genitive complement of ἱερόν. The form Λαμπείᾳ is treated as a dative place-name agreeing with ὄρει; exact case/declension of the toponym is somewhat uncertain.

εἴη δʼ ἂν τοῦ ὄρους τοῦ Ἐρυμάνθου μοῖρα ἡ Λάμπεια.

Existential/copular optative: ἡ Λάμπεια is the nominative subject and μοῖρα the predicate nominal; τοῦ ὄρους τοῦ Ἐρυμάνθου is a genitive specification of μοῖρα.

ἐποίησε δὲ Ὅμηρος ὡς ἐν Ταϋγέτῳ τε καὶ Ἐρυμάνθῳ θηρευτὴς οὖν τῆς Λαμπείας ὁ Ἐρύμανθος, καὶ Ἀρκαδίαν διεξελθὼν ἐν δεξιᾷ μὲν τὸ ὄρος ἔχων τὴν Φολόην, ἐν ἀριστερᾷ δὲ πάλιν Θέλπουσαν χώραν, κάτεισιν ἐς τὸν Ἀλφειόν.

The sentence begins with a Homeric framing clause (ἐποίησε Ὅμηρος ὡς...) and then gives a descriptive movement clause; the repeated nominative Ἐρύμανθος serves as the explicit subject of κάτεισιν, with θηρευτής as its predicative characterization.