THE ROLE OF CELL-SIZE IN DETERMINATION OF MORPHOGENESIS OF THE STOMATA IN LEAVES OF SEVERAL LAMYOID LABIATEAE

The number of cell divisions leading to the stomata formation depends on the size of the secondary and tertiary meristemoids. If the corresp onding meristemoid does not exceed a certain critical size, it can bec ome the maternal cell of the closing stomata cells. Otherwise, it divi des heteronomously and gives rise to a meristemoid of the next order, whose fate is also determined by its size. The critical size differs i n various species and increases with the leaf blade.