It will be seen that the structure of trailing arbutus leaf is very simple and that its structure is different from that of klip buchu and mountain laurel.
The structure of powdered leaves is very variable, yet characteristic for a given species. The leaves from the insect flower plant are collected with the stems, and ground and sold as a substitute for insect flowers. These leaves, when powdered, show the following structure (Plate 112):
PLATE 110
Cross-Section Mountain Laurel (Kalmia latifolia, L.)
1. Hair. 2. Epidermis. 3. Palisade parenchyma. 4. Parenchyma. 5. Under epidermis. 6. Intercellular space. 7. Rosette crystal. 8. Chlorophyll.
PLATE 111
Cross-Section Trailing Arbutus Leaf (Epigæa repens, L.)
1. Stomata. 2. Epidermis. 3. Parenchyma. 4. Cell with chlorophyll. 5. Intercellular space. 6. Under epidermis. 7. Rosette crystal.
Both the upper and lower epidermis have stomata (Figs. 1 and 2), but they differ in that the surrounding cells of the upper epidermis are wavy, while the corresponding cells of the under epidermis are similar, though the under epidermis has many attached hairs (Figs. 3 and 4). The T-shaped hairs form the most abundant element of the powder. They are similar in structure to those found on the scales and stem. Fragments of the mesophyll have round cells and contain chlorophyll (Fig. 6). The conducting cells are spiral or reticulate.
The different cells of the leaf differ greatly in structure, in amount, and in arrangement. In uva-ursi, boldus, pilocarpus, eucalyptus, and chimaphila leaves the outer walls of the epidermal cell is very thick. In uva-ursi leaves this thick wall appears bluish green when viewed under low power of the microscope.