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1.
 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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  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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Cornus L. s. 1. is a large polytypic genus. The classificantion of which has been so different that some authors recognize several separate genera, while others treat them as ei- ther subgenera or sections.  New evidence from many disciplines such as palynology, cyto- logy, wood anatomy and embryology supports the view that the genus should remain in the broad sense.  I basically agree with the treatment by Ferguson (1966b) before my finishing a comprehensive study on Cornus L. s. 1. except for supporting  the separation  of subgenus Afrocrania as an independent genus.  A new subgenus Sinocornus Q. Y. Xiang, containing one species, C. chinensis Wangerin, is established here on account of its inflorescence axillary and different from the other members of the genus which all have terminal inflorescences only. The inflorescence developed from a terminal bud implicates the sympodial nature of axis of stem and the one from an axillary bud the monopodial one.   It is reasonable to regard the character as of subgeneric value.  Also a new combination, Cornus subgen. Syncarpea (Na- kai) Q. Y. Xiang, is proposed here as a substitute for Cornus subgen.  Benthamia (C. B. Clar- ke) Schneider used for a long time.  Because the valid publication of the former name subgen. Syncarpea Nakai is earlier than the latter one.  The types of inflorescences of 8 subgenera re- presented by type or selected species are illustrated.  相似文献   

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报道了蔷薇科李亚科两个种的改隶新组合,将广义李属中的背毛樱Prunus hypotrichodes改隶为杏属中的背毛杏Armeniaca hypotrichides;疏花稠李Prunus laxiflora改隶为疏花樱Cerasus laxifiora。进一步研究的结果,同意前苏联学者G.V.Eremin et V.S.Simagin的意见,将稠李属中的种斑叶稠李Padus maackii改隶为樱属中的斑叶樱Cerasus maackii。  相似文献   

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The present paper reports the first record of the genus Hymenopyramis in China. H. cana is a new record on Hainan Island of Guangdong Province. It grows in deciduous mon- soon forests or shrubby savanna (western Hainan) at 50 to 150 m alt.  相似文献   

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本文以云南西北部怒江峡谷的豹子花属及其近缘的百合属、大百合属和贝母属的12个分类群为 材料,分析比较了这几个属的核形态特征。 12个分类群的体细胞静止期染色体形态相似,均属于复杂染色中心微粒型;有丝分裂前期染色体形态也相似,都属于中间型;染色体数目均为2n=24;染色体着丝点端化值在79.9-82.2%之间;核型不对称程度一致;故这4个属的关系密切。对本地区的12个分类群来说,核型变异主要在于次缢痕位置的差别。豹子花属和百合属在它们的一对m或sm染色体近着丝点处具有次缢痕,并且豹子花属和高海拔处的百合属植物(如L.souliei)在其st或t染色体的短臂上缺乏次缢痕,表明豹子花属同百合属特别是同高海拔处的百合属植物关系密切。  相似文献   

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Pyrgophyllum (Gagnep.) T. L. Wu et Z. Y. Chen is a monotypic genus of Zingibera- ceae from China.  Originally, it was placed in Kaempferia as a subgenus by Gagnepain (1901), later transferred to Camptandra by Schumann (1904) and to Caulokaempferia by R. M. Smith. (1972).        In this paper, the authors suggest that the separation of Pyrgophyllum at generic rank is justified on cytological, morphological and anatomical evidence.  It is characterised by the large lamina-like bracts, which are rarely seen in Zingiberaceae.  The margin of each bract is ad- nate to the main axis of the inflorescence at the base and the lip is lobed.  Trichomes unicel- lular, stomata each with 4-7 lateral subsidiary cells, lateral veins are of three various types of vascular bundles: girder-shaped, semigirder-shaped and isolated. The pollen grains are spinecent. The basic chromosome number (x) is 21.       The type species, Pyrgophyllum yunnanensis (Gagnep.) T. L. Wu et Z. Y. Chen (Kaemp- feria yunnanensis Gagnep.), is only distributed in Yunnan and Sichuan provinces of China.    相似文献   

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   在对广义的罗汉果属进行形态学、解剖学,孢粉学、细胞染色体数目和植物地理学研究的基础 上,进一步对该属作了分类学的修订。  主张将罗汉果属的三个亚属提升为三个属即自兼果属、小球瓜属和罗汉果属。  相似文献   

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 When F. A. McClure published the new genus Sinocalamus McClure in 1940, the 4 species he listed are S. latiflorus (Munro) McClure, S. beecheyanus (Munro) Mc- Clure, S. oldhami (Munro) McClure and S. affinis (Rendle) McClure.  After careful examination, the authors of this paper considered that the type species of McClure’s genus S. latiflorus (Munro) McClure should belong to the genus Dendrocalamus Nees, and the other species are of Bambusa Schreber.  Owing to Sinocalamus McClure is not a taxon representative of its type species, but a mixture, it must be rejected as a synonym of Dendrocalamus Nees.  In consequence then, the authors make adjustment to the taxonomic category of the 14 species and 1 variety which have ever been in Sinocalamus McClure.      As for the characters of Lingnania McClure, except that some differences exist in the vegetative parts, the structure of the spikelets is in the main the same as that of Bambusa Schreber.  Consequently, with regard to the systematic relationship, the authors consider it may be more resonable that the rank of Lingnania McClure should be alter- ed to Bambusa Schreber subg.  Lingnania (MeClure) Chia  et H. L. Fung; all the species of Lingnania McClure, except that L. tsiangii McClure should be transferred to Dendrocalamus Nees, should be assignable to Bambusa Schreber subg.  Lingnania (McClure) Chia et H. L. Fung.  相似文献   

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 In the present paper a new species of Lasallia Merat is described and placed under a new subgenus Pleiogyra, characterized by having econcentrical multi-gyrate apothecia. In consequence of this finding, the conception of plane disc in the genus Lasallia of Umbili- cariaceae becomes untenable.      As a result of careful examination of rich materials, the writer considers the dif- ference in disc found by Scholander among all species of the family is of certain signifi- cance for classification.  Unfortunately, Scholander’s classification is based solely on this rather variable morphological character.  If his view be adopted the new species will have to be inserted into the genus Gyrophora Ach. emend. Schol.  If accepting Llano’s division of Umbilicariaceae into five genera, namely Lasallia, Agyrophora, Omphalodiscus, Umbili- caria and Actinogyra, the new species will have to be considered a new  genus  of  the family.      The present writer considers both Scholander’s and Llano’s systems as being artificial, because the former author emphasizes too much the unstable morphological appearance of disc and the later simply divides the family into five genera simultaneously on the basis of the stable and unstable characters of the various groups.  In contrast with Scholander’s and Llano’s systems Frey’s classification neglects wholly the difference in the characters of disc.  Such treatment is likewise unsound.  The present writer supports the view held by Flotow, Koerber, Elenkin and Savicz (1950).  Nevertheless, he does not agree with Savicz in erecting the subgenus Gyrophoropsis (Elenk. et Savicz) Savicz, because muriform spores are present not only in the group having gyrate discs, but also in the groups having plane and omphalic discs of the Genus Umbilicaria Hoffm. emend. Vej.  The recognition of this subgenus must therefore deny the basis on which the other four subgenera are established.       The system of Umbilicariaceae held by the writer is as follows: I. Genus Lasallia Merat emend. Vej  ......  Thallus pustulate; disc plane to econcentrical multi-gyrate; spores     1(2) per ascus, quite large, muriform.     1. Subgenus Lasallia...Disc plane.    2. Subgenus Pleiogyra Vej  ......  Disc econcentrical multigyrate. II. Genus Umbilicaria Hoffm. emend. Vej (syn. Gyrophora Ach. emend. Savicz)* ...Thallus non-pustulate;    disc plane and smooth or plane with central sterile column (or fissure) or with gyri; spores 8 per ascus,    simple, hyaline or becoming brown muriform, small. 1. Subgenns Agyrophora (Nyl.) Savicz  ......  Disc plane.    (1) Section Agyrophora (syn. sect. Anthracinae emend. Llano). .....  Spores simple and hyaline.    (2) Section Dichroae Llano  ......  Spores becoming brown muriform. 2. Subgenus Omphalodiscus (Schol.) Savicz  ......  Disc with central sterile column or fissure.    (1) Section Omphalodiscus (syn. sect. Decussatae Schol.)  ......  Spores simple and hyaline.    (2) Section Spodochroae Schol.  .....  Spores becoming muriform. 3. Subgenus Umbilicaria...Disc with concentrical gyri; spores simple and hyaline or becoming muriform.    (1) Section Umbilicaria (syn. sect. Simplices Llano)  ......  Spores simple and hyaline.    (2) Section Gyrophoropsis (Elenk. et Savicz) A. Zahlbr. (syn. sect. Muriformes Llano)  ......  Spores          becoming muriform.4. Subgenus Actinogyra (Schol.) Savicz  ......  Disc with radial gyri, proper margin absent.  相似文献   

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中国苔类植物新记录属──服部苔属   总被引:1,自引:0,他引:1  
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综合研究凤头黍属与其邻近属的叶片表皮微形态、颖片及内、外稃等特征后,发表禾本科一新属——刺毛头黍属。  相似文献   

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