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Pollen Morphology of the Genus Nomocharis and Its Delimitation with Lilium


In this work examined were pollen grains of 6 species of Nomocharis and
4 species of Lilium, all under LM and SEM, but Nomocharis saluenensis Balf. f. under
TEM.  The pollen grains are monocolpate (distal) in Nomocharis, monocolpate or 2-
3-porate in the species of Lilium examined. Two types of pollen grains in Nomocharis
are recognized based upon the exine stratification and sculpture.
      The pollen characters and gross morphology, and their evolutionary trends in both
Nomocharis and Lilium are discussed.  Our conclusions are as follows:
     1.  Lilium henrici Franch. 、L. souliei (Franch.) Sealy 、L. lophophorum (Bur.
et Franch.) Franch. and L. nanum Klotz. et Garcke differ from Nomocharis in the ape-
rture and sculpturing elements.  Their pollen morphology supports their being placed
in Lilium.
      2.  The pollen grains of both Lilium lophophorum (Bur. et Franch.) Franch. and
L. nanum aggregate are monocolpate or 2-3-porate, which shows an evolutionary trend
of aperture from monocolpate to porate, as suggested by Walker and others [Walker
et al., (1975), and Chanda (1979)].
     3.  In Balfour’s (1918) classification system of Nomocharis, N. pardanthina Franch.
and N. meleagrina Franch. belong to Sect. Nomocharis, while N. forrestii and N. biluo-
ensis are placed in Sect. Ecristata, but their pollen grains are all reticulate.  They refer
to type I (see Table 2).  Thus, it does not seem reasonable placing in a single section,
Sect. Ecristata, N. forrestii and N. biluoensis with the reticulate exine and N. saluenen-
sis and N. aperta with the two-row-ritipilate exine.
     4.  Nomocharis saluenensis Balf. f. differs from Lilium in the exine sculpture, which
seems to support placing it in Nomocharis.
     5.  Muri of N. forrestii Balf f. and N. biluoensis s.y. Liang show a tendency of
connecting each other by heads of pili, and these two species are intergraded with the
other species of the type I with respect to gross morphorlogical characters.  It is thus
considered that the reticulate pollen grains in Nomocharis is derived from ritipilate
ones.  This opinion is also held by Nair (1965).
     6.  Nomocharis differs from Lilium in the exine ornamentation, but some species
of Nomocharis are very similar to Lilium in the gross morphology.  It shows the close
affinity between Nomocharis and Lilium.


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