In a flowering frond, a distinct elliptical furrow was observed on the dorsal surface exposing the floral organs (Fig. 3), usually to one side of the median antero-posterior axis. As an initial step of flowering, primordia of stamen and pistil (which might represent are duced form of male and female flowers, respectively, of an inflorescence) develop at the posterior and anterior side, respectively,in the floral cavity formed at an eccentric position. Developing primordia inside the frond give rise to the appearance of mounds on the dorsal surface. A furrow on the dorsal surface which exposes these immature floral organs (Fig. 3a and b) soon develops into a circular rim-like protuberance which grows over the developing floral organs arching them completely and covering the original opening(Fig. 3c)