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One new section and one new species of the genus  Carex  (Cyperaceae) are described from Anhui  Province,  China.  i. e. Sect.  Cyclostyliferae  and  Carex shuchengensis S. W. Su et Q. Zhang.  相似文献   

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In addition, two new  sections,  Echinochlomorphae Y.  L.  Chang and Thomsonianae Y. L. Chang, two new combinations,  C.  duriuscula  subsp.  rigescens (Franch.) S. Y. Liang et Y. C. Tang (=C. stenophylla var. rigescens Franch.) and C. rochebrunii Franch. Subsp. reptans (Franch.) S.  Y.  Liang et Y. C. Tang (=C. remotae  L. var. reptans  Franch.) are  made,  and C. stenophylloides V. Krecz. is reduced to C. duriuscula subsp.  stenophylloides  (V. Krecz.) S.  Y. Liang et Y. C.Tang.  相似文献   

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本文对我国苔草属二柱苔草亚属Subgen.Vignea作了系统排列,并提出以下几点的看法:     1.二柱苔草亚属是苔草属中比较自然的一个类群,我国有48种、7亚种和1变种,隶属于16个 组。根据Takhtajan的世界植物区划,将它们分成4种成分,即:(1)环北方植物地区成分,占总数的 20.4%;(2)东亚植物地区成分,占总数的55.5%。实际上,只有4个分类群出现于中国-喜马拉雅森 林植物亚区,而其余的都均分布于中国-日本森林植物亚区,并且在这一亚区内有8个特有成分,占特 有成分总数的61.5%;显然,中国二柱苔草亚属在中国-日本森林植物亚区内的分化较其他地区更为强 烈;(3)伊朗—吐兰植物地区成分,占总数的16.7%;(4)印度支那植物地区成分和印度植物地区成 分,占总数的7.4%。     2.高节苔草C.thomsonii和云雾苔草C.nubigena类群是Subgen.Vignea中较为原始的种类, 它们为印度支那植物地区和印度植物地区成分。这样非但Subgen.Indocarex原始类群分布于东南亚 和马来西亚,而Subgea.Vignea的原始类群也分布于东南亚,这也是对Nelmes提出Carex起源于印度-马来西亚地区的一个佐证。  相似文献   

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 选择中国复序苔草亚属6组4亚组的代表植物14种,进行了叶片解剖学研究,观察了其横切面 和表皮特征,证明上述特征在各类群之间存在差异,具有一定的系统学意义。这14种植物叶片的横切 面和表皮都具有一些原始的性状,表明复序苔草亚属中的植物可能在苔草属中是较原始的。在所观察 的植物中,Sect.Polystachyae植物叶片解剖学特征比较一致,说明此组的建立比较合理;而Sect.Indicae 组已有明显分化,尤其是Carex scaposa C.B.Clarke和C.densifimbriata Tang et S.Y.Liang 与其它植物明显不同,而且其外部形态特征在复序苔草亚属中也比较独特,因此赞成将它们及其近缘类群做为一个组而非亚组。  相似文献   

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Sixteen new species and two new varieties of the genus Carex are described from China.  相似文献   

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本文用扫描电镜观察了泽苔草的花器官发生过程,观察结果表明:花萼以螺旋状方式向心发生,花瓣以接近轮状方式近同时发生,不存在花瓣雄蕊复合原基。雄蕊和心皮均以轮状向心方式发生,6枚雄蕊分两轮分别在对萼和对瓣的位置先后发生,至发育的后期排成一轮,但仍分别处于对萼和对瓣的位置;随后发生的第一轮3个心皮原基与3枚萼片相对,第二、三轮心皮原基分别为1~3个,与前一轮心皮相间排列向心发生。本文首次揭示了泽苔草花被的外轮3个萼片螺旋状发生方式,这种螺旋状方式很可能是泽泻科植物的花部结构在进化过程中适应环境而保留下来的一种较原始的叶性特征。  相似文献   

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通过扫描电镜观察了宽叶泽苔草Caldesia grandisSamuel.的花器官发生。宽叶泽苔草 的萼片3枚,逆时针螺旋向心发生 ;花瓣3枚,呈一轮近同时发生,未观察到花瓣_雄蕊复合原基;雄蕊、心皮原基皆轮状向心 发生,最先近同时发生的6枚原基全部发育成雄蕊,随后发生的6枚原基早期并无差别,在发 育过程中逐渐出现形态差异,直至其中1-4枚发育成心皮,其余的发育成雄蕊;而后的几轮 心皮原基,6枚一轮,陆续向心相间发生。本文揭示了3枚萼片螺旋状的发生方式,并推测这种螺旋方式是泽泻科植物进化过程中保留下来  相似文献   

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三江平原地区毛果苔草群落的研究   总被引:3,自引:0,他引:3  
毛果苔草(Carex lasiocarpa)群落是三江平原地区沼泽植被的主要类型,分布广,面积大。毛果苔草不但是群落的优势种,而且是形成泥炭的最主要的造炭植被。本文主要探讨毛果苔草的基本特征:①生物学生态学特性;②毛果苔草和泥炭形成关系;③毛果苔草的养分和化学元素特性; 三江平原、毛果苔草群落、沼泽植被  相似文献   

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eterachopsis was proposed by the senior author as an independent genus of the family Aspleniaceae in 1940 with 2 species.  Since then much study on its morpho- logy,  anatomy,  gametophyte and palynology has been carried out by Nayar,  Bir,  Chan- dra & Nayar and Chang et al.,  and they are of the opinion that the genus like Ceterach, is a comparatively primitive element in the family Aspleniaceae.  The queer zigzag pa- tern of cutting of lanceolate fronds appears extraordinary in the family Aspleniaceae, and also suggests its antiquity in evolution. So far only 3 species  (C.  dalhousiae,  C. paucivenosa and C. magnifica) are recognized,  the former from W. Himalayas,  also known from Africa,  while the latter two from W. S. China (Yunnan).  However,  in the past forty years the Chinese botanists have discovered 2 more species as new in N. W. Yunnan,  thus bringing the total known species of the genus up to 5.  The present paper is a brief summary on the genus Ceterachopsis,  which will be published in detail in the Flora Sinica vol. 4.       Pteridologists are also divided in their views regarding the generic status of Cete- rachopsis with 5 well-defined species in Yunnan and the East Himalayas.  We prefer to mintain it as a genus separate from Asplenium on account of its distinct morpholo- gical features.  It is to be hoped that more species may come to light in the mountainsin N. W. Yunnan through further exploration now under way.  相似文献   

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乌蒙杓兰及其近亲种   总被引:1,自引:0,他引:1  
 In addition to describing a new species, Cypripedium wumengense, as well as a new variety, C. bardolphianum var. zhongdianense,  nomenclatural and taxonomic notes are made on its allies and the division to which they belong.  They are ltrge]y found in the Hengduan Mountains in southwestern China, characterized by the absence of bract, havirg lip more or less covered with small wart-like outgrowths, and that as the capsule matures the scape becomes much elongated.  Six species of this group have hitherto been reported, of which, however, C. ebracteatum and C. nutans are regarded here as conspecific with C. fargesii and C. bardolphianum respectively. Thus, including the new taxa described here, it composes five species and one variety: C. bardolphianum W. W. Sm. et Farrer (var. bardolphianum and var. zhongdianense S. C. Chen), C. mic- ranthum Franch., C. fargesii Franch., C. margaritaceum Franch. and C. wumengense S. C. Chen.  They are all grouped here into the same section, Sect.  Trigonopedium (Franch.) Pfitz., the oldest legitimate name of this group in the rank of section.  相似文献   

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中国沙拐枣属新植物   总被引:1,自引:0,他引:1  
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The karyotypes of 3 species of Ceratoides (C. arborescens,  C. ewersman- niana and C. latens) were studied. The results show that C. arborescens is a diploid, with karyotype formula 2n=2x=18=16m+2sm,  C. ewersmanniana is also a diploid,  with 2n=2x=18=14m+4sm,  while C. latens is a tetraploid,  with 2n=4x=36=24m+12sm. Ac- cording to the karyotypes,  the morphological features and geographical distribution,  C. arborescens seems to be a primitive species and it might have originated in northern China. C. arborescens and C. ewersmanniana are similar to each other,  not only in mor- phology but also in karyotype,  which shows that they are closely related and that C. ar- borescens might be the progenitor of C. ewersmanniana. The karyotypes of the 3 speciesof Ceratoides are basically identical,  with only minor differences.  相似文献   

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In order to get a thorough understanding of the Characeae, the specime- ns collected from Guangxi and Gansu were identified.  The result shows  that  the two provinces, especially Guangxi, are abundant in this family.  In this paper,  ho- wever, reported are only new species, new varieties and new records of Chara in China. They are Chara vernicosa sp. nov. C. globularis var. inflata var. nov. and C. howe-ana var. subgymnophylla var. nov., C. brionica stapf and C. calveraensis comb. nov.  相似文献   

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 One new species Coloniophora shanxiensis Y. J. Ling et S. L. Xie, is described,and one new record, C. spicata (Schmid.) Islam, is reported both from shanxi, China.  相似文献   

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