CALCIUM CRYSTALS IN THE LEAVES OF SOME SPECIES OF MORACEAE

The type, morphology, and distribution of calcium oxalate and calcium carbonate crystals in mature leaves of nine species (eight genera) of Moraceae were studied. All the studied species contain calcium crystal s. Based on types of crystals, these species can be classified into th ree groups: (a) species with only calcium oxalate: Artocarpus altilis and Cudrania cochinchinensis; (b) species with only calcium carbonate: Fatoua pilosa and Humulus scandens; and, (c) species with both calciu m oxalate and calcium carbonate: Broussonetia papyrifera, Ficus elasti ca, Ficus virgata, Malaisia scandens, and Morus australis. The calcium oxalate crystals were mainly found as druses or prismatic crystals. D ruses were located in the crystal cells of both mesophyll and bundle s heath, but prismatic crystals were found only in cells of the bundle s heath. All calcium carbonate cystoliths were located in the epidermal lithocysts, and the types of lithocysts were related to the number of epidermal layers, i.e. hair-like lithocysts in uniseriate epidermis an d papillate lithocysts in multiseriate epidermis.