Fig. 1.

Paradermal sections of MCs as they appear in the light microscope after staining with toluidine blue. (Α) Palisade-like MCs in paradermal view. Arrows indicate cell contacts and arrowheads cell isthmi. Asterisks mark cell lobes in an external paradermal semi-thin section. The double arrow indicates the leaf axis in (A–C). (B) MCs were located laterally to vascular bundles. Large arrows show contacts of MCs with bundle sheath cells. Small arrows point to MC contacts and arrowheads to MC isthmi. BSC, bundle sheath cell. (C) A single layer of MCs intervenes between two adjacent vascular bundles. The large arrowhead indicates a cell isthmus parallel to the leaf axis, while the small arrowheads show cell isthmi transverse to the leaf axis. TW, transverse wall. Scale bars = 10 μm.