Example 16. Adaptations of the ➑–➐–➏–➎ proto-theme that progress from I to III: (a) basic form, with ˆ8 as Kopfton; (b) basic form, with ˆ5 as Kopfton; (c) interpolated chords e and f, with ˆ8 as Kopfton; (d) interpolated chords e and f, with ˆ5 as Kopfton