Abstract: In the present study, floral organogenesis of Saururus chinensis was observed and compared with that of S. cernuus. The two species share essentially similar patterns of floral initiation and stamen development. Their inflorescence produces “common primordial” in acropetal succession on the flanks of the inflorescence meristem. Each primordium bifurcates transversely to form a floral apex above and a bract primordium below. Six stamens arise in three pairs at the floral apex. The median sagittal pair arises first,the lateral distal pair second, and the lateral proximal pair arises last. On the contrary, the initiation of carpels is quite different from each other. In S. cernuus, the median sagittal pair arises first,and the lateral pair next. In S. chinensis, however, the lateral pair arises first, and the median sagittal pair second. The present study also made a brief generalization using the data obtained from different fields on the relationship of the two species in the genus Saururus, which are disjunctly distributed between eastern Asia and North America.

Key words: Floral organogenesis, Saururus chinensis