Abstract:Leaf epidermis of 35 species of Ormosia in China was examined under light microscope (LM) andscanning electron microscope (SEM). The epidermal cells of both upper and lower leaf surfaces are polygonal or irregular in shape, anticlinal walls are straight, arched, sinuolate or sinuate, and stomata are elliptic or ovate. Stomatal apparatuses which occur only on abaxial surface of the leaflets are mainly of paracytic type, but in species such as O. balansae and O. pinnata, the paracytic type sometimes concurs to have anomocytic or anisocytic type，while the stomatal apparatuses are indistinct in a few species such as 0．sericeolucida and 0．pachycarpa．The ornamentation ofthe outer stomatal ledge (or rim) is smooth，or granular，or granular and striate，or indistinct；the inner margin of the outer stomatal ledge is smoo饥or nearly smooth，or sinuolate or indistinct；the wax ornam entation is smooth，or granular，or scaly，or striate，or granular and reticulate．Trichomes on the leanets were observed．These leaf epiderm al characters can be used to distingu ish species or varieties within Ormosia, which exhibits that OFmosia is a homogenous natural group.
