Figure 6. Chart depicting admissible divisions of different kinds of whole tone. Vicentino defines five categories of whole tone intervals in the 31-tone system according to whether their starting and ending pitches are written as naturals, “natural enharmonic” pitches, sharps, flats, or flats inflected enharmonically. In each case the tone is divided unequally into three minor dieses and one major diesis, and in each case there are two admissible ways to execute this division. The larger arc in each image represents the single step of a major diesis. The diagrams for each of the five types of whole tone have been slid horizontally so that similar accidentals are vertically aligned. This lets us see that the pitches skipped over, whatever their relative position in the whole tone being subdivided, are always naturals, sharps, or flats. Pitches written with a dot (either “natural enharmonic” or with an enharmonic dot in conjunction with a flat) are always included; thus the aural structure of a correctly divided whole tone depends on its notation and absolute pitch level.