Abstract: The microcharacteristics of seed surface in Lysimachia of the family Primulaceae were investigated by light microscope (LM) and scanning electron microscope (SEM). Based on the morphological characters of seed epidermis cells, the seeds coats can be divided into two distinct types, Heterogenea-type and Grammica-type. 7 species of Subgen. Palladia of China all belong to Heterogenea-type, and 4 species of Subgen. Lysimachia of China to Grammica- type. The results show that there are remarkable differences in the morphological features of seed surface between subgen. Palladia and subgen. Lysimachia, which might have significant taxonomic implications at subgenus level .

Key words: Lysimachia