The formal scheme of Rex Magne domine resembles those of the D-final melodies, except in the more elaborate shape of its final phrase. This melody, like the D-final melodies, shows motivic correspondence among its different phrase shapes. Its total set of motives, however, is smaller than the motivic set in a D-final melody like Clemens rector aeterne, and—what is more important—much of the melody is free of these motivic relationships. The E-final melody of Rex Magne domine, which compares in ambitus with fourth mode chants, contrasts sharply both with its Gregorian counterparts and with the D-final Kyries. Rex magne domine could be understood in the same way, as having a primary focal pitch on E and a secondary focal pitch a third higher on G, yet the tonal organization of this melody is not comparable to that of a D-final melody that closes some of its phrases on a.