Fig. 4. Proximity of mutant and non-mutant stomatal files marking the boundary region. The number of cell files separating individual wild-type stomata from the nearest mutant stoma was counted for a total of 453 stomatal pairs. For 0 files, n=13; 1 file, n=36; 2 files, n=83; 3 files, n=141; 4 files, n=107; 5 or more files, n=73.