The daylily pistil is formed from three carpels that fuse very early in the development of the pistil. However, there is just one open channel in the centre of the pistil for most of its length until it is close to the ovary. Nevertheless, pollen tubes that grow down through the channel may be guided into any of the three different sections of the ovary and some sections may not receive good pollen or something else may happen to cause the ovules in a section to not develop or to abort later. The diagram below shows the open channel in the pistil (based on Pollen-tube behavior in Hemerocallis with special reference to incompatibilities by Stout and Chandler, Plate 23 figures 5, 6 & 7).
