The leaves of Hymenodictyon orixence are simple, opposite decussate, stipulate and petiolate. The leaf measures about 12-30 cm in length and 8-15 cm in width, elliptic in shape, with an abruptly acute apex. The margin is entire, with the base narrowed into a petiole, which is about 2.5–7 cm long and hairy. Dark green above and pale below, the young leaves are silvery and clustered at the end of branches. The stipule is interpetiolar, triangular or broadly ovate, obtuse recurved and deciduous.
The midrib is elevated on both the surfaces, with the upper being conical and lower semicircular in outline. Inner to the epidermis there is a few layered collenchyma followed by large parenchyma. Vascular bundle shallow is 'U' shaped with incurved margins. The xylem strands are few and embedded in phloem .
Upper epidermal cells are larger than the lower ones. Both the surfaces have multicellular, uniseriate trichomes measuring up to 250–400 µ, stomata are paracytic [Figures and ] and restricted to the lower side only. Other important characters are given in the table .
Micro and macroscopic characters
Behavior of leaf powder with different chemical reagents was studied to detect the presence of phytoconstituents with colour changes under day light and the results were presented in the table .
The colour of the plant extract is mainly due to its chemical composition. The same extract may appear different in different wavelength of light. Kokashi et al
] studied the behavior of different vegetable drugs under UV radiation and found that different drugs exhibit different colours and those colours were characteristic for the particular drug. In our study we found a specific colour pattern which is characteristic for Hymenodictyon orixence
, and hence can be used as a finger print for crude drug identification .