A study led by Dr. Yin-Zheng Wang (Institute of Botany, the Chinese Academy of Sciences) has found that the stigma of Chirita pumila has movement and proved that the motion is associated with water sensitivity. Further, through anatomical studies, it was found that when the stigma absorbed water, a type of cell accounting for half of the volume of the stigma was greatly extended, which was closely related to the extension-contraction movement of the stigma. The new cells are named contractile cells.
