Studies on the Chemical Constituents of Gnetum montanum Markg The Structure Anomalous Secondary Growth of Stem in Gnetum montanum THE ANOMALOUS SECONDARY GROWTH OF ROOTS IN GNETUM MONTANUM Pharmacognostic identification of stem of Gnetum montanum Comparation in Nutrient Components of Gnetum montanum f. megalocarpa Leaves under Two Cultivated Environment