Questions of Greek Grammar

...and it is itself isosyllabic, namely of all feminine nouns ending in α or η, whose genitive is in ας or ης, and dative in α or η, and the accusative ends in ν with the vowel of the nominative.

Maia, maiae, maiae, maian, O maia. Dual: Maiae, maiarum, and maiis, O maiae. Plural: Maiae, maiarum, maiis, maias, O maiae.

Musa, musae, musae, musan, O musa. Dual: musae, musarum, and musis, O musae. Plural: musae, musarum, musis, musas, O musae.

Honor, honoris, honori, honorem, O honor. Dual: honores, honorum, and honoribus, O honores. Plural: honores, honorum, honoribus, honores, O honores.

Note in this second declension, those that have a pure α, or with ρ, retain that α even in the genitive, as maia, maiae; dies, diei.
Those that indeed have another consonant before α, if it is δ or θ, they make the genitive in ας, leda, ledae; the name caprae. If however they have another consonant, they change the α into η, as musa, musae; sitis, sitis; lingua, linguae; mare, maris.

Third declension.

The third declension of the noun is in masculines, feminines, and neuters, also itself isosyllabic, namely of certain masculines and feminines ending in ως with long ω, and neuters ending in ων with long ω, whose genitive and dative end in long ω, and the accusative in long ων.