The hollow circle in the diagrams is the root in a major scale, and the hollow circle with a dot in the center is the root in a minor scale. The shapes suggest various ways for you to visualize the basic pattern of the hexatonic scale shown by the Dots. The fretmap that best demonstrates the symmetry of the hexatonic scale is the Double L.
|Clock||Dots||Broken Diagonals||Double L||Note Cluster||3 times 2|
The Broken Diagonals show that you can get through the six notes in the hexatonic scale by repeatedly moving five semitones down, starting from the root in major. The sequence then becomes 1-5-2-6-3-7 (the pentatonic scale with the 7th added). The Double L is great since it clearly shows that the shape of the 5-6-7 group is the 'mirror image' of the 1-2-3 group. It is extremely useful in practice because it makes it very easy to jump between the two groups. The Note Cluster and 3 times 2 also have appealing shapes but are harder to convert into left-hand fingerings.