Discussion of genitive endings formed with 'o', 'eo', 'ao' in Attic, Ionic, Boeotian dialects; rules for accentuation (proparoxytone, paroxytone, properispomenon) depending on original accent and syllable weight; examples (Priam, Menestheus, Minos, Atreides, Orestes, Aineias, Hermes, Asia, Thales); contraction of trisyllables (laaos→laos, kear→kēros, ear→ēros) and question about ois/oios.
οἷον φίλου φίλοιο, κούφου κούφοιο, Πριάμου Πριάμοιο. Τὰ ἀπὸ Ἀττικῶν γενικῶν κατὰ πλεονασμὸν τοῦ 'ο' γινόμενα, εἰ μὲν ἀπὸ ὀξυτόνων γενικῶν Ἀττικῶν ὦσι, προπερισπῶνται οἷον Πετεώ Πετεῶο »υἱὸς Πετεῶο Μενεσθεύς« (Β 552). »ὦ υἱὲ Πετεῶο Διοτρεφέος βασιλῆος« (Δ 338), Ταλαώ Ταλαῶο ὡς παρὰ Ἀντιμάχῳ· εἰ δὲ ἀπὸ βαρυτόνων γενικῶν Ἀττικῶν ὦσι, προπαροξύνονται οἷον τοῦ Μίνω τοῦ Μίνωο, τοῦ Ἀνδρόγεω Ἀνδρογέωο. τοῦ δὲ 'ο' προσελθόντος κατεβιβάσθη μίαν συλλαβὴν ὁ τόνος διὰ τὸ μὴ δύνασθαι τετάρτην ἀπὸ τέλους εἶναι τὴν ὀξεῖαν. Αἱ διὰ τοῦ 'εω' γενικαὶ Ἰωνικαί, εἰ μὲν ἀπὸ βαρυτόνων κοινῶν γενικῶν ὦσι, προπαροξύνονται οἷον Ἀτρείδου Ἀτρείδεω, Ὀρέστου Ὀρέστεω, Αἰνείου Αἰνείεω, ἀπαθεῖς δηλονότι οὖσαι· ἐὰν γὰρ πάθωσι, πρὸ μιᾶς τοῦ τέλους ἔχουσι τὴν ὀξεῖαν οἷον Ἑρμείου Ἑρμείεω καὶ κατὰ συγκοπὴν Ἑρμείω παροξυτόνως »Ἥρης Ἑρμείω τε« (Ο 214), Ἀσίας Ἀσίου καὶ Ἰωνικῶς Ἀσίεω καὶ Ἀσίω ὡς εὐμμελίω »Ἀσίω ἐν λειμῶνι« (Β 461). εἰ δὲ ἀπὸ περισπωμένων κοινῶν γενικῶν ὦσι, παροξύνονται οἷον αὐλητοῦ αὐλητέω, Θαλῆς Θαλοῦ (ἔστι δὲ ὄνομα κύριον) τοῦ Θαλέω. Αἱ διὰ τοῦ 'αο' Βοιωτικαὶ γενικαί, εἰ μὲν ἀπὸ βαρυτόνων κοινῶν γενικῶν ὦσι, προπαροξύνονται οἷον Ἀτρείδου Ἀτρείδαο, Ὀρέστου Ὀρέσταο, εἰ δὲ ἀπὸ περισπωμένων κοινῶν γενικῶν ὦσι, προπερισπῶνται οἷον ἀργεστής ἀργεστοῦ, ἀργεστᾶο »ἀργεστᾶο νότοιο« (Λ 306). Πᾶσα γενικὴ δισύλλαβος εἰς 'ος' λήγουσα μὴ συναληλιμμένη ὀξύνεται, μηνός, χηνός, Ζηνός, φωτός. ἡ λᾶος ἐκ τρισυλλάβου τῆς λάαος κράσει τῶν δύο 'α' εἰς ἓν μακρόν, ἡ κῆρος καὶ ἦρος ἐκ τῆς κέαρος καὶ ἔαρος. ἀποροῦσι δέ τινες λέγοντες, εἰ ἄρα τὸ λᾶος καὶ κῆρος καὶ ἦρος ὡς δυνάμει τρισύλλαβα ἐβαρύνθησαν, διὰ ποίαν αἰτίαν τὸ ὄϊς ὄϊος γενόμενον κατὰ συναίρεσιν οἶς οἰός μὴ ἐβαρύνθη; καὶ τοῦτο γὰρ δυνάμει τρισύλλαβόν ἐστιν. ἔστιν οὖν εἰπεῖν, ὅτι τὸ μὲν λᾶος καὶ κῆρος καὶ ἦρος οὐ μόνον ἐν τῇ εὐθείᾳ συναιροῦνται, ἀλλὰ καὶ ἐν τῇ γενικῇ οἷον λᾶας λᾶς λάαος λᾶος, κέαρ κῆρ κέαρος κῆρος, ἔαρ ἦρ ἔαρος ἦρος καὶ τούτου χάριν ὡς δυνάμει τρισύλλαβα ὄντα ἐν τῇ γενικῇ ἐβαρύνθησαν. τὸ δὲ οἶς οἰός οὐκ ἔπαθεν ἐν τῇ γενικῇ συναίρεσιν ἀλλ´
For example: φίλου φίλοιο, κούφου κούφοιο, Πριάμου Πριάμοιο. The forms produced from Attic genitives by the addition of an extra ο: if they are from oxytone Attic genitives, they are accented with a circumflex on the antepenult, e.g. Πετεώ Πετεῶο: “son of Πετεῶο, Μενεσθεύς” (Β 552); “O son of Πετεῶο, king nourished by Zeus” (Δ 338); Ταλαώ Ταλαῶο, as in Antimachus. But if they are from barytone Attic genitives, they are accented with an acute on the preantepenult, e.g. τοῦ Μίνω τοῦ Μίνωο, τοῦ Ἀνδρόγεω Ἀνδρογέωο. And when the ο has been added, the accent has been lowered by one syllable, because the acute cannot stand on the fourth syllable from the end. The Ionic genitives in -εω: if they are from barytone common genitives, they are accented with an acute on the preantepenult, e.g. Ἀτρείδου Ἀτρείδεω, Ὀρέστου Ὀρέστεω, Αἰνείου Αἰνίεω, being, of course, unaffected; for if they undergo affection, they have the acute one syllable before the end, e.g. Ἑρμείου Ἑρμείεω, and by syncope Ἑρμείω with an acute on the penult: “and to Ἑρμείω of Hera” (Ο 214); Ἀσίας Ἀσίου, and in Ionic Ἀσίεω and Ἀσίω, as in Εὐμμελίω: “in the meadow of Ἀσίω” (Β 461). But if they are from common genitives with a circumflex, they are accented with an acute on the penult, e.g. αὐλητοῦ αὐλητέω; Θαλῆς Θαλοῦ (it is a proper name), τοῦ Θαλέω. The Boeotian genitives in -αο: if they are from barytone common genitives, they are accented with an acute on the preantepenult, e.g. Ἀτρείδου Ἀτρείδαο, Ὀρέστου Ὀρέσταο; but if they are from common genitives with a circumflex, they are accented with a circumflex on the antepenult, e.g. ἀργεστής ἀργεστοῦ, ἀργεστᾶο: “of the ἀργεστᾶο south wind” (Λ 306). Every disyllabic genitive ending in -ος that is not contracted is accented with an acute: μηνός, χηνός, Ζηνός, φωτός. λᾶος comes from the trisyllable λάαος by contraction of the two α into one long vowel; and κῆρος and ἦρος from κέαρος and ἔαρος. Some raise a difficulty, saying: if λᾶος and κῆρος and ἦρος, as being trisyllabic in potential, have been made barytone, for what reason has ὄϊς, whose genitive ὄϊος by contraction becomes οἶς οἰός, not been made barytone? For this too is trisyllabic in potential. One may therefore say that λᾶος and κῆρος and ἦρος are contracted not only in the nominative, but also in the genitive, e.g. λᾶας λᾶς, λάαος λᾶος; κέαρ κῆρ, κέαρος κῆρος; ἔαρ ἦρ, ἔαρος ἦρος; and for this reason, as being trisyllabic in potential, they have been made barytone in the genitive. But οἶς οἰός has not undergone contraction in the genitive, but—