Ind

Abstract

Bark anatomy of white pulai (Alstonia scholaris R.Br.). black pulai (Alstonia angustiloba Miq.) and bintaro (Cerbera manghas L.) were observed and described for identification purposes. These plants have been used as sources of traditional medicine in South East Asia. Bark of these trees exudes white gum when it was cut; the inner parts are white. The outer surfaces of A. scholaris and C. manghas are gray and usually lenticellate; the outer surface of A. angustiloba contains no lenticel, and the colour is dark brown . with narrow and shallow longitudinal fissures. The main components of bark are phloem, parenchyma, ray, fibre, sclereid and periderm. Fibres are tangentially arranged near the cambium ofjuvenile stem of all species, then pushed outward by cambium activity as the age of the plant increased. Sclereids were few and thin walled while the plants were young and then increased in quantity and in cell wall thickness as the plants become mature. The main anatomical differences between bark of these plants were in the morphology of the sclereids. Sclereids of A. scholaris are short and chubby, sclereid of A. angustiloba are long and stout while those of C. manghas are long and slender. A tentative identification key is presented.