(a,b) Cell volumes, (c,d) cell packing densities, and (e,f) total mesophyll surface area per tissue volume (SAmes/Vmes) in leaves scale with 2C genome size across vascular plants (angiosperms, blue; gymnosperms, orange; ferns and fern allies, grey). Minimum cell volumes (modelled from cell diameters) and maximum cell packing densities are limited by the size of meristematic cells (solid lines). Measurements of meristematic cells as a function of genome size in log-log space (b, solid line; from [19]) are reproduced in arithmetic space (a). Theoretical maximum packing density of meristematic cells (c,d) was calculated from measured cell volumes [19] as the reciprocal of meristematic cell cross-sectional area (see Material and methods) assuming spherically shaped cells.