To the left: Rod-shaped crystalloid at the seed coat of a Mesembryanthemum species (Sceletium, Aizoaceae). Two types of rods occur: short and long ones. To the right: Thread-like flavonoid crystalloid of a bird's-eye primerose leaf (Primulaceae). Thread-shaped flavonoid crystals of this kind can only be found with certain primulas and a few ferns. (W. BARTHLOTT, 1981, W. BARTHLOTT, E. WOLLENWEBER, 1981)
To the left: Unusually complex wax structures at the leaf undersurface of a tropical plant (Bellusia pentamera, Melastomataceae). The free stomates are clearly visible (S. RENNER, 1986 unpublished) To the right: Parallel wax plates at the shoot of an asparagus (Asparagus). Strictly oriented wax plates are without exception restricted to certain monocot orders which can be classified by this feature (W. BARTHLOTT, 1981, W. BARTHLOTT, E. WOLLENWEBER, 1981)
Upper picture: Shoot surface of Colletia spec. (Rhamnaceae). The striking tube-shaped structures are chimneys. Every one of them has a stomate at its base. The chimneys influence the transpiration of the strongly xeromorphical plants that live in arid regions of South America. Lower Picture: Fungi hyphens at the leaf surface of Prosopsis spec, a species of the Mimosaceae family. The crystalloid wax plates around the hyphens are vanished. The fungi may now spread across the unprotected surface. (W. BARTHLOTT, 1981, W. BARTHLOTT, E. WOLLENWEBER, 1981, W. BARTHLOTT, 1985 unpublished)