Although these three genera have some differences in floral organogenesis, they have some common primordial characters, such as have spiral initiation mode and numerous stamen primordial etc.

• 4．莼菜属、睡莲属和芡属，他们在花器官发生上虽然有一些明显区别，但同时又具一些共同的原始特征，特别是三属的花器官发生均具有螺旋状向心发生的方式，都产生多数雄蕊原基等。