Leaves of Stevia cinerascens plants , with pleasant smell (sample A ) and without perfume (sample B), which present differences in size and develop under different environmental conditions, were the object of this work. The leaf architecture was studied in clarified leaves and the anatomy in cuts of living or fixed material. The area occupied by the epidermal cells, stomata and trichomes according to the stereological method was determined. In these plants, the leaves have dorsiventral structure, are amphistomatic with anomocotic stomata. The trichomes are simple - conical and filiform - and glandular vesiculous vesicles. Venation is acronym. The vascular bundles are collateral, and the smaller mesophyll bundles have a parenchyma sheath. The vessel elements have simple drill plate. Schizogenous secretory channels occur in the primary nerves and occasionally in the secondary nerves. The supporting tissue is the colenchyma that occurs along the larger veins. Sample sheetsA and B are structurally differentiated by the differentiation of bisserial glandular trichomes, alpha subtype (sample A ) beta (sample B ), and by frequent characters in sun sheets (sample A ) and shadow sheets (sample B ).
