Macroscopic: Leaflets, 2.5-6 cm long and 7-15 mm wide at center, pale yellowish-green, elongated lanceolate, slightly asymmetric at base; margins entire, flat, apex acute with a sharp spine; both surfaces smooth with sparce trichomes; odour, faint but distinctive; taste, mucilaginous and disagreeable but not distinctly bitter.
Microscopic:Transverse section of leaflet through midrib shows an isobilateral structure; epidermal cells, straight walled, containing mucilage; both surfaces bear scattered, unicellular hair, often conical, curved near base, thick-walled, non-lignified; warty cuticle; stomata, paracytic, numerous on both surfaces; mesophyll consists of upper and lower palisade layers with spongy layer in between; palisade cells of upper surface longer than those of lower surface, the latter having wavy anticlinal walls; prismatic crystals of calcium oxalate present in larger veins, and clusters of calcium oxalate crystal distributed throughout the palisade and spongy tissues; midrib biconvex; bundles of midrib and larger veins, incompletely surrounded by a zone pericyclic fibres and a crystal sheath of parenchymatous cells, containing prismatic crystals of calcium oxalate.