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  The present paper concerns itself with three Composite genera of the tribe Cynareae  (subtribe Carduinae), Vladimiria Ilj., Diplazoptilon Ling and Dolomiaea DC., all ranging  throughout the Sino-himalayan region,  These genera have in the past always been as-  sociated with the Eurasiatic genus Jurinea Cass., though there is hardly anything that  can indicate such a relationship. Jurinea, according to the conception of Iljin, is a clearly  deliminated natural genus, while the three genera now in question are all closely allied to  Saussurea DC., being quite remote from Jurinea in the corolla forms,  the structure  of  receptacle and pappus, and also in the morphology of pollen grains.        Vladimiria was founded by Iljin, based on  Jurinea  salwinensis Hand.-Mzt.  The  genus is a close relative of Saussurea from which it differs chiefly in the usually many  seriate pappus which are composed of scabrous or partly barbellulate bristles.  As a re-  sult of our study, a tentative scheme of classification is here proposed, in which Iljin's  original generic concept has been amplified to include a dozen of species previously re-  ferred to Jurinea by Franchet, Diels, Anthony and Handel-Mazzetti from  the  flora  of  south-western China and adjacent countries.  Two sections, namely,  sect. Sorocephalos  Ling and sect. Vladimiria (Saussurea sect. Carduella Franch., Mazzettia Ilj.), are being proposed.       Diplazoptilon, a new monotypic genus based upon Jurinea picridifolia Hand.-Mzt., is here proposed.  It occupies an intermediate position between Vladimiria and Saussurea with a closer affinity to the former, from both of which  it is,  however,  distinguished chiefly by the biseriate pappus with equal plumose bristles.                          Dolomiaea, a natural genus early founded by De Candolle on the basis of the Hima- layan D. macrocephala DC., was considered by Bentham and Hooker f. as not different from Jurinea, a treatment having being followed since by most botanists  of  the past. But, as mentioned above, its relationship with Saussurea is obvious.  It seems to differ from that genus in the two to many seriate pappus, consisting of numerous barbellulate bristles, and in the short style branches.  In view of its affinity with  Saussurea rather than with Jurinea, the generic status of Dolomiaea should be maintained accordingly.  As construed above, the genus is now represented by about 5 species, most of which werepreviously referred to Jurinea by different botanists.  相似文献   
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菊科一新属——紊蒿属   总被引:1,自引:0,他引:1  
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 The present paper is an attempt to throw some light on two Composite genera, Cavea W. W. Smith et Small and Nannoglottis Maxim., of which the generic  features and the systematic position were heretofore rather badly known.       Cavea, a monotypic genus based upon Saussurea salwinensis Drumm., was described by W. W. Smith and Small as monocious.  From the ample material now in our com- mand, it is found that the genus is either monocious and dioecious, the capitula in the latter case being homogamous.  The individuals exclusively provided with sterile flowers are usually smaller in size, sometimes even stemless.   Such  repartition  of  sexes  was known in the subtribe Plucheinae (tribe Inuleae), to which W. W. Smith and Small were correct to ascribe their genus.       Nannoglottis was considered by Maximovicz as un abnormal  genus  of  the  tribe Inuleae, having heterogamous capitula with one series of peripheric fertile ligulate pistil- late flowers.  Having examined the type specimen of N. carpesioices Maxim. and the ex- tensive collection from Kansu and Tsinghai, we incline to say that the genetic characters as discerned by Maximovicz are doubtlessly due  to  his  inaccurate  observation.   The flowers of Nannoglottis are in fact trimorphous, of which the  pistillate ones  are  2-3- seriate, the outer being shortly ligulate and the inner, short-tubulate with truncate apex. Handel-Mazzetti, much later, indicated that, in another species, the pistillate flowers are 2-3-seriate, but no mention was made about the inner tubulate pistillate flowers.       Franchet, appearing to be unware of Maximovicz's genus, founded his Stereosanthus Franch. and considered it as a genus intermediate between the tribes Inuleae and Sene- cioneae.  The genus was misinterpreted by Franchet as having dimorphous flowers, the pistillate ones being all ligulate.  Curious enough, one of the major generic features, viz., the presence of inner tubulate pistillate flowers, was neglected by all early botanists and was first recognized by Handel-Mazzetti fourty years later.       However, Handel-Mazzetti was still unacquainted with the characters of Nannoglot- tis and proposed therefore his new genus Vierhapperia Hand.-Mzt. on the reason that the flowers are trimorphous.  Moreover, he compared his genus with Conyza L. and Erigeron L. of the tribe Astereae, but the characters marked by him appear not to be different from those of Nannoglottis.       From the above morphological comparaison, it is evident that Nannoglottis and two other genera in question possess in common important characters in the general appea- rance, the flower-forms and the structure of achenes and pappus.  The differences in the disposition of involucral bracts and the length of ligules are criteria good for separating species, but can hardly be regarded as sufficient  for  generic  delimitation.   Moreover, these three genera are almost similar in their geographical distribution.  These points are adequate to warrant that Stereosanthus and Vierhapperia are in reality congeneric with Nannoglottis.      Nannoglottis appears to have been correctly placed by Hoffmann  in  the subtribe Senecioninae (tribe Senecioneae) though in that subtribe it finds no close relatives.  On account of the outstanding characters of the genus, a further study of its systematic posi- tion is required.      The present paper is brought to close by a tentative scheme of classification of the genus so amplified, of which two sections, namely, sect. Stenolepis Ling et Y. L. Chen (Stereosanthus Franch., p. p. min.) and sect. Nannoglottis  (Stereosanthus  Franch., p. p.maxim.; Vierhapperia Hand.-Mzt.), altogether including 9 species, are being proposed.  相似文献   
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