Polymerous Leaf Whorls in Vascular Plants: Developmental Morphology and Fuzziness of Organ Identities

  title={Polymerous Leaf Whorls in Vascular Plants: Developmental Morphology and Fuzziness of Organ Identities},
  author={Rolf Rutishauser},
  journal={International Journal of Plant Sciences},
  pages={S81 - S103}
  • R. Rutishauser
  • Published 1 November 1999
  • Environmental Science
  • International Journal of Plant Sciences
In vascular plants there are at least eight ways to develop polymerous whorls, i.e., whorls with four or more leaves. Six ways are presented and compared with literature to estimate organ identity (morphological significance) of the leaflike whorl members. New shoots (also seedlings) may start with dimerous or trimerous whorls. Then leaf number per whorl rises as follows: (1) Many taxa add more leaves per whorl continuously with increasing size of the apical meristem (e.g., Equisetum, Hippuris… 

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