Microscopic characteristics
Epicarp with very thick cuticularized isodiametrical cells, occasional anomocytic or paracytic stomata, and very few unicellular and warty trichomes; hypodermis with collenchymatous cells; mesocarp with parenchymatous tissue containing a layer of calcium oxalate prisms; endocarp consisting of thick-walled fibre, mostly perpendicular to the longitudinal axis of the fruit, but the inner fibres running at an oblique angle or parallel to the longitudinal axis. Seeds, subepidermal layer of palisade cells with thick outer walls; the endosperm has polyhedral cells with mucilaginous walls (2).