1. Leaf undersurface of the tree fern Cibotium schiedei. Extremely high number of stomates per unit in a species living in tropic cloud forests. 2. Stomate at the leaf undersurface of a boxtree (Buxus sempervirens). The boxtree has no special ecological preference but it is the best micromorphological example of embossed stomates.
3. and 4. Shoot epidermis of the xeromorph cactus Rhipsalis dissimilis. 3. Epidermis in top view. The crater-shaped depressions with a guard cell each at their base can be recognized. d Cross-section through the epidermis and the underlying tissues. The guard cells are deeply countersunk, the cuticle is extremely thick. Both takings (3 and 4) show the classic adaptation of a xerophyte. (W. BARTHLOTT, 1981, 1986)
