Abstract: The comparative anatomy of vegetative organs of 24 species and six varieties of Vitis from China in presented in this paper. The anatomical characteristics of stems, nodes, petioles and leaves, such as vascular system, hairs, sclerenchyma, collenchyma and foliar cuticular papillae, were examined in detail. The main characteristics of vegetative organs of Vitis,observed in the persent work, are as follows: (1) In the transverse section of stems, the vascular bundles were separated by medullary rays. The number of medullary rays was variable in the genus, e. g. 18--22 in V. wuhanensis, 37--40 in V. piloso-nervosa. (2) The nodes of Vitis were multilacunar, with 4--8 traces from an equal number of gaps. (3) The transverse section of petioles in the middle part exhibited a ring of bundles, accompanied by two, or less frequently more, cortical bundles on either side of the groove. Two types of the ring were recognized: the closed ring type (continous vascular bundles) and the false ring type (separate vascular bundles connected by streaks of lignified parenchyma). The anatomical structure of petioles can be classified into three types according to the number and the arrangement of bundles. (4) In the cross section at the base of the primary vein of leaf blades, vascular bundles were isolated. Based on the number of bundles, the anatomical structure of leaf blades can be divided into three types. (5) Several kinds of hairs were found: unicellular, uniseriate, stalked-glandular, shortly stalked uniseriate and spiny-like multicellular. The occurrence of raphides is characteristic of the Vitaceae, including the genus Vitis. Interspecific differences of anatomical structure in Vitis are useful for distinguishing some species, and can be applied to discussinfg systematics and phylogeny. It is found that the number of vascular bundles are obviously correlated with the size of leaves and stems. The variation of bundles in Vitis is therefore probably an adaptation. Two evolutionary tendencies of the number of bundles in Vitis are proposed: the increase in somespecies, and the decrease in the others.

Key words: Vitis, Comparative anatomy, Systematics