In J. sambac, although the embryo sac belongs to the Polygonumtype, most of the opening flowers can be thought as female ster-ile because of abnormal development of ovules. Morphological andanatomical observations have elucidated the possibilities leadingto the formation of sterile ovules. Both female-sterile and female-fertile flowers have developed similarly during the early stages;the two types of ovule differentiate mainly during the late periodof development (i.e., Stages IV and V). This phenomenon is sim-ilar to the formation of fertile and sterile flowers in Viburnummacrocephalum f. keteleeri (Jin et al., 2010). However, in the latter,sterile flowers had larger corollas than fertile ones (Jin et al., 2010).Because a large floral display can effectively attract pollinators andenhance pollen export and receipt, this divergence in flower fertil-ity is an evolutionary consequence of long-term ecological selectionfor reproductive success (Jin et al., 2010). In the present study, how-ever, it has been found that no obvious differences in floral displaybetween flowers containing normal and abnormal ovules. There-fore, both ecological and evolutionary mechanisms resulting in theabnormal development of ovules in jasmine are still unclear andrequire a further investigation.