head type 1
Eb2-14 Eb2-20 Eb2-24 Eb2-27 Eb3-6 Eb3-19 Eb3-25
1 2 3 4 5 6 7
         
Eb3-28 Eb3-31          
8 9          
head type 2
Eb4-1 Eb4-6 Eb4-12 Eb4-21 Eb4-25 Eb4-27 Eb4-31
10 11 12 13 14 15 16
head type 3
Eb5-3 Eb5-9 Eb5-13 Eb5-17 Eb5-20 Eb5-24 Eb5-28
17 18 19 20 21 22 23
           
Eb6-19            
24            

Exceptional heads are marked with red numbers, other marks with red glyph numbers.

24 - 9 (red glyphs) = 15 (non-red glyphs).