Abstract: Pollen grains of 18 species or varieties of the genus Paris ( Trilli-aceae)have been examined under light microscope and scanning electron microscope. All the species examined are characterized in having oblate and anacolpate pollen grains. The size of the pollen grains ranges from 27 to 30 um in the polar axis and from 48 to 55 um in the longest equatorial axis. The exine is twolayered, with sexine equal to or thicker than nexine in thickness. The ornamentations of the exine are foveolate, reticulate and rugulato-reticulate according to different species under scanning electron microscope. The ornamentation of the exine in Paris axialis and P. forrestii is more diverse and complicated than in any other species of the genus. These two species can be grouped together on the basis of pollen morphology, especially the simila-rities between their exine ornamentations in having muri which are characterized by possession of clavate, nodose and tuberculate or verrucate structures, which gives support to Li Hen who placed the two species in the same section of Axiparis H. Li. But how to treat those species with foveolate exine ornamentation is still a problem and needs futher study by absorbing other subjects.

Key words: Paris