ɪnðə ɹᵻlˈeɪɾᵻd fˈæmɪli bᵻtʃəlˈeɪsiː, nˈoʊɾəbli ɪnðə dʒˈɛnɚɹə kˈɑːɹpɪnəs ænd kˈɔːɹɪləs, ðə kjˈuːpjuːl ɪz ɹᵻplˈeɪst baɪ ɐn ɪnvˈɑːlʌkɚ, wˌɪtʃ dˈɪfɚz ɪn bˌiːɪŋ mˈoːɹ lˈiːfi ɪn ɐpˈɪɹəns, bˌʌt pɚfˈɔːɹmz ɐ sˈɪmɪlɚ ɹˈoʊl ɪn pɹətˈɛktɪŋ ðə dɪvˈɛləpɪŋ nˈʌts.
In the related family Betulaceae, notably in the genera Carpinus and Corylus, the cupule is replaced by an involucre, which differs in being more leafy in appearance, but performs a similar role in protecting the developing nuts.