FIGURE 3. Characterization of the idioblasts of Capparis odoratissima . (a) Maximum 3D projection of an isolated idioblast showing their typical structure of a small tubular projection towards the adaxial epidermis (top) and irregular walls toward the abaxial surface. (b) Cells of the adaxial epidermis are thick and have substantial extracellular materials (blue color) that intersperse with the thick adaxial cuticle (white arrowheads). (c) The idioblasts are columnar within the palisade parenchyma, with thick refringent walls and narrow lumens (arrow). (d) At the level of the spongy mesophyll, numerous canals connect the idioblast lumen with the surrounding mesophyll cells. (e) At the abaxial epidermis, adjacent idioblasts anastomose and form an irregular structure that connects with the center of the peltate hairs. B-D semi-thin sections stained with toluidine blue for general structure. C, cuticle; ep, epidermis; pp, palisade parenchyma; id, idioblast; sp, spongy parenchyma; ph, peltate hair. Dotted arrows in A indicate the plane of section of images on the right. Scale bars: a = 100µm; b-e = 20µm.