Floral morphology, mode of anther dehiscence and percentage of pollen viability in four Cassia species, sensu lato, i.e. C. fistula, C. siamea, C. renigera and C. javanica has been analyzed. These species exhibit diversity in the size of stamens, mode of anther dehiscence and percentage of pollen viability. There are three types of anthers large, medium and small designated as A, B and C type respectively. These dehisce by longitudinal slit, basal or an apical pore. Pollen grains in all the three types of anthers are viable. Staminodes are absent.