Abstract: Floral ontogeny of Kadsura coccinea, K.japonica and K.angustifolia was studied under scanning electron microscope (SEM).The results show that three species have two different floral ontogenetic patterns.Flowers of three species share similar patterns of floral initiation and early development, but diverge in subsequent stages.The similarities of flowers in the initiation and early development supports that Kadsura may be monophyletic.The differences in later stages serve as an evidence of distinguishing the Subgenus Cosbaea and the Subgenus Kadsura in the genus Kadsura.Floral morphology of K.borneensis and K.lanceolata was observed under SEM, the results serve as an evidence of distinguishing the Section Kadsura and the Section Sarcocarpon in the Subgenus Kadsura according as the flowers of K.japonica and K.angustifolia were compared with those of K.borneensis and K.lanceolata.Because the bisexual vestigial structures or a few bisexual flower were observed in K.angustifolia or Schisandra elongata, the results indicate that the unisexual flower in the family Schisandraceae may be derived from the bisexual ancestor.According to the similarties of stigmata between the families Schisandraceae and Illiciaceae, the viewpoint that Schisandraceae was divided from the order Illiciales and the order Schisandrales was foundated is not supported.

Key words: Kadsura, floral morphology, phylogeny