Abstract: Strictly speaking, the focus of the present essay is Petrarch's "Sestina 22" ("A qualunque animale alberga in terra") in Canzoniere; however, the peculiarities of the Petrarchan sestina will also be touched upon, including the relationship of Petrarch's poetic practice with that of his actual forerunners. In this respect, the provençal Arnaut Daniel and Dante will be mentioned. The essay aims at providing an analysis of the role end-words play in generating both meaning and theme. In addition, a special emphasis will be laid upon examining their sound effect and the functions these words carry in the given poetic idiom. Furthermore, a scrutiny will be given to the envoy and its relations to permutation and rhymes occurring at stanza-closures as well as to questions of versification and genre.