Fig. 12.

SEM illustrations of gynostemium from adult flowers at anthesis. a Empty anthers, pollen grains grouped in tetrads germinated on stigma. b Magnification of a, empty anthers. c Magnification of a, pollen grains germinated on median stigmatic lobe. d Magnification of c, germinating of pollen tetrads. e Pollen fallen out from anthers of this plant and adhering to the rostellum-viscidium. f Magnification of e, pollen grains from the anthers of this plant but germination of pollen grains not observed (a anther, lsl lateral stigmatic lobe, msl median stigmatic lobe, rv rostellum-viscidium, s staminodium)