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1.
 The genus Solms-Laubachia of Cruciferae was established by Muschler in 1912 on the basis of the Chinese species Solms-Laubachia pulcherrima of Yunnan Province. Since then, nine species, two varieties and two forms have been recorded.  They are almost all endemic in China except one species—Solms-Laubachia retropilosa Botsch. which was discovered in Sikkim.      We described in this paper thirteen species, three varieties and one form, of which, we suppose, three species, one variety and one combination have never been reported before.  Most species grow in the mountainous regions of Szechuan, Yunnan, Tibet,Ching-hai and Sinkiang in China.  相似文献   

2.
 Xizang (Tibet) is rich in Leguminosae flora, comprising 41 genera and 254 species so far known, exclusive of the commonly cultivated taxa (including 11 genera and 16 species). There are 4 endemic genera (with 8 species), 10 temperate genera (with 175 species) and 19 tropical genera (with 46 species) as well as the representatives of those genera whose distribution centers are in East Asia-North  America, Mediterranean and Central Asia.       1.  There are altogether 4 endemic genera of Leguminosae in this region. Accord- ing to their morphological characters, systematic position and geographical distribution, it would appear that Salweenia and Piptanthus are Tertiary paleo-endemics, while Straceya and Cochlianths are neo-endemics. Salweenia and Piptanthus may be some of more primitive members in the subfamily Papilionasae and their allies are largely distributed in the southern Hemisphere.  The other two genera might have been derived from the northern temperate genus Hedysarum and the East Asian-North American genus Apios respectively, because of their morphological resemblance. They probably came into existanc during the uplifting of the Himalayas.       2. An analysis of temperate genera       There are twelve temperate genera of Leguminosae in the region, of which the more important elements in composition of flora, is Astragalus, Oxytropis and Cara- gana.       Astragalus  is a  cosmopolitan  genus comprising 2000 species, with its center distribution in Central Asia. 250 species, are from China so far known, in alpine zone of Southwest and Northwest, with 70 species extending farther to the Himalayas and Xizang Plateau.       Among them, there are 7 species (10%) common to Central Asia, 12 species (15.7%) to Southwest China and 40 species (60%) are endemic, it indicates that the differentia- tion of the species of the genus in the region is very active, especially in the subgenus Pogonophace with beards in stigma. 27 species amounting to 78.5% of the total species of the subgenus, are distributed in this region.  The species in the region mainly occur in alpine zone between altitude of 3500—300 m. above sea-level. They have developed into a member of representative of arid and cold alpine regions.      The endemic species of Astragalus in Xizang might be formed by specialization of the alien and native elements. It will be proved by a series of horizontal and vertical vicarism of endemic species.  For example, Astragalus bomiensis and A. englerianus are horizontal and vertical vicarism species, the former being distributed in southeast part of Xizang and the latter in Yunnan; also A. arnoldii and A. chomutovii, the former being an endemic on Xizang Plateau and latter in Central Asia.      The genus Oxytropis comprises 300 species which are mainly distributed in the north temperate zone. About 100 species are from China so far known, with 40 species extending to Himalayas and Xizang Plateau.  The distribution, formation and differ- entiation of the genus in this region are resembled to Astragalus.  These two genera are usually growing together, composing the main accompanying elements of alpine mea- dow and steppe.      Caragana is an endemic genus in Eurasian temperate zone and one of constructive elements of alpine bush-wood. About 100 species are from China, with 16 species in Xi- zang. According to the elements of composition, 4 species are common to Inner Mon- golia and Kausu, 4 species to Southwest of China, the others are endemic. This not only indicates that the species of Caragana in Xizang is closely related to those species of above mentioned regions, but the differentiation of the genus in the region is obviously effected by the uplifting of Himalayas, thus leading to the formations of endemic species reaching up to 50%.      3. An Analysis of Tropical Genera      There are 19 tropical genera in the region. They concentrate in southeast of Xizang and southern flank of the Himalayas. All of them but Indigofera and Desmodium are represented by a few species, especially the endemic species. Thus, it can be seen that they are less differentiated than the temperate genera.      However, the genus Desmodium which extends from tropical southeast and northeast Asia to Mexio is more active in differentiation than the other genera. According to Oha- Shi,s system about the genus in 1973, the species of Desmodium distributed in Sino-Hima- laya region mostly belong to the subgenus Dollinera and subgenus Podocarpium.  The subgenus Dollinera concentrates in both Sino-Himalaya region and Indo-China with 14 species, of which 7 species are endemic in Sino-Himalaya.  They are closely related to species of Indo-China, southern Yunnan and Assam and shows tha tthey have close con- nections in origin and that the former might be derived from the latter.      Another subgenus extending from subtropical to temperate zone is Podocarpium. Five out of the total eight species belonging to the subgenus are distributed in Sino- Himalaya and three of them are endemic.      An investigation on interspecific evolutionary relationship and geographic distribu- tion of the subgenus shows that the primary center of differentiation of Podocarpium is in the Sino-Himalaya region.      Finally, our survey shows that owing to the uplifting of the Himalayas which has brought about complicated geographic and climatic situations, the favorable conditions have been provided not only for the formation of the species but also for the genus in cer-tain degree.  相似文献   

3.
 This paper is a preliminary study on the Sabiaceae in aspects of its morphology, taxonomy and geography.  We propose that the Sabioideae and Meliosmoideae as two new subfamilies of Sabiaceae according to the external morphology, flower structure and geographical distribution of these two genera respectively.       This paper follows the taxonomic concepts of Luetha Chen on Sabia and C. F. van Beusekom on Meliosma.  We agree with them for their classification of these two genera above the specific rank.  As to the revision work of Sabia by van de Water and C. F. van Beusekom’s work on Meliosma we disagree  for their unduly broad specific concepts.  We rather treat the species of these two genera according to their habitats in regions on a relatively narrower sense.  The genus Sabia of China are classified into 2 tribes, with 16 species, 5 subspecies and 2 varieties in which 4 sub- species and l variety are as new combinations, the genus of Meliosma in China are classified into 2 subgenera with 29 species, and 7 varieties of which 4 varieties are new combinations.       After examining the affinity of the species of Sabia and Meliosma in China and its neighboring nations such as Burma, Japan and Bhutan, we found that their migra- tion initiated from China, as the primitive species of these two genera occured in northeast and central part of Yunnan, sou theast of Sichuan, north of Guizhou and west of Hubei, the region may probably be the main origin of these two genera.      As shown in tables 1 & 2, the localities where the species of these two genera den- sely populate they are from Yunnan, Guangxi, and Guangdong coinciding with the concepts of C. F. van Beusekom and van de Water about the distribution of exotic species of these two genera, it may reasonable be pointed out that the center of distri- bution of these two genera is Yunnan, Guangxi, Guangdong and nieghboring nations, upper Burma and northern Vietnam.  Futhermore, it may be seen that starting from this center the number of species become less and less as they proceed far and far awaybut become more advance in evolution.  相似文献   

4.
5.
 The “Iconographia Plantarum” written by Wu Chi-Tseng in the Qing Dynasty (A. D. 1848) is a classical monumental work in the literature of botany. 1714 species of plants widely-spread all over 19 provinces of our country, especeally in Jiangxi, Hunan and Yunnan Provinces, were described in this book. nan and Yunnan Provinces, were described try, especeally in Jiangxi, Hunan and Yun.      In order to make the plant names coincide with the original material as possible, the author had commented upon chinese herbal in considerable detail.  Most of the plants were illustrated after their habitual appearence in somewhat clear manner. As a means for identifying certain species of the plant, this work has been playing an important role in development of modern botanical science in China.      In modern taxonomical books a great deal of chinese name of plants are originated from this book, and they were available for reference to numerous researchers both at home and abroad. On account of inadequate observation, a lot of mistakes or misleadings occured in this book, and often been overlooked by the later botanists.  Some of the modern authors still adhere to the work “Iconographia Plantarum”and even quoting the erroneous statement from it, thus we have to correct.      This paper annotates and commentates the misleading items of 36 species of plant, and calls for the attention to the future readers.    相似文献   

6.
7.
8.
 Yunnan is extends across the subtropical and tropical zones, situated in the sou- thern border area of southwestern China.  This district is extremely rich in plants, and thus, it has been known as a “Kingdom of Plants”.  However, up to the present our knowledge of the Charophyta in this region has been scanty.      In order to get a thorough understanding of its Charophyta, we identified speci- mens collected from 13 countries or cities in this province.  The result shows that is especially abundant in Charophyta.      In this paper, however, only are reported new species, new varieties and new re- cords of China on the Nitelleae.  The former two are Nitella hokouensis, N. bicornuta, N. longicaudata, N. procera, N. brevidactyla, N. papillata, N. pseudohyalina, N. hyalina var. aberrans and Tolypella yunnanensis; while the third is Nitella globulifera Pal andN. japonica T. F. Allen.  相似文献   

9.
海菜花属的分类、地理分布和系统发育   总被引:1,自引:0,他引:1  
 The genus Ottelia is one of the great genera of Hydrocharidaceae.  About 25 spe- cies distributed in the Palaeotropics, extending from Africa through India and SE. Asia to Korea and Japan, Australia and New Caledonia, 1 species in Brazil; centres of specific devolopment are found in Central Africa and SE Asia.      The present study is mainly based on the materials collected during the field ex- plorations in the lakes of Yunnan and observations on the structure of the spathe and flowers, the variation of leaf of the plants cultivated in Kunming Bot. Garden. Instead of the wings of the spathe used by Dandy, by the characters such as uni-or bisexual flowers, this genus is divided into two subgenera, which by the number of the flowers in spathe and the number of the carpus in ovary again subdivided into 4 sections.  They are as the following:      A. Subg. Ottelia.  Flowers bisexual.      Sect. 1. Ottelia.  Spathe with 1 flower; ovary with 6(—9) carpus.      Sect. 2. Oligolobos (Gagnep.) Dandy. Spathe with many flowers; ovary with 3 car- pus.      B. Subg. Boottia (Wall.) Dandy.  Flowers unisexual; the male spathe with 1-many flowers, the female spathe with many flowers.      Sect. 3. Boottia.  The male spathe with 1 flower; ovary with 9(—15) carpus.      Sect. 4.  Xystrolobos (Gagnep.) H. Li.  The female spathe with (2-) many flow- ers; ovary with 3 or 9 carpus.      The Chinense species of ottelia is in great need for revision.  All of the species in China previousely described under Ottelia Pers, Boottia Wall., Oligolobos Gagnep, and Xystrolobos Gagen. are here combined into 3 species.  They are O. alismoides, O. cor- data, O. acuminata with 4 variaties.      After a study of the geographic distribution and infer relation-ships among the floristic elements it has been proved that Ottelia is certainly an ancient genus, and the primitive types came into being and widely dispersed before the separation of Laurasia from Gondwana.      During a considerable period of time the elements of the genus Ottelia in fresh- water environment of different continents have been separately differentiated and evolv- ed into more or less derived types.  The structure of flowers in all of the asian species shows the following evolutionary tendenoes: 1. In this genus the plants with unisexual flowers have evolved from plants with bisexual flower; 2.  In the groups with bisexual or unisexual flowers the number of stamens and styles reduced to 3-merous, but the number of flowers in spathe increased. So that the subgenus Ottelia is more primitive than the subgenus Bottia; While in the subgenus Ottelia O. alismoides is a more primi- tive than O. balansae and in the subgenus Boottia O. cordata is the most primitive, butO. alata seems to be the most advanced.  相似文献   

10.
木兰科分类系统的初步研究   总被引:10,自引:0,他引:10  
A new system of classification of Magnoliaceae proposed.  This paper deals mainly with taxonomy and phytogeography of the family Magnoliaceae on the basis of external morphology, wood anatomy and palynology.  Different  authors have had different ideas about the delimitation of genera of this family, their controversy being carried on through more than one hundred years (Table I).  Since I have been engaged in the work of the Flora Reipublicae Popularis Sinicae, I have accumulated a considerable amount of information and material and have investigated the living plants at their natural localities, which enable me to find out the evolutionary tendencies and primitive morphological characters of various genera of the family.  According to the evolutionary tendencies of the characters and the geographical distribution of this family I propose a new system by dividing it into two subfamilies, Magnolioideae and Liriodendroideae Law (1979), two tribes, Magnolieae and Michelieae Law, four subtribes, Manglietiinae Law, Magnoliinae, Elmerrilliinae Law and Micheliinae, and fifteen genera (Fig. 1 ), a system which is different from those by J. D. Dandy (1964-1974) and the other authors.      The recent distribution and possible survival centre of Magnoliaceae. The members of Magnoliaceae are distributed chiefly in temperate and tropical zones of the Northern Hemisphere, ——Southeast Asia and southeast North America, but a few genera and species also occur in the Malay Archipelago and Brazil of the Southern Hemisphere. Forty species of 4 genera occur in America, among which one genus (Dugendiodendron) is endemic to the continent, while about 200 species of 14 genera occur in Southeast Asia, of which 12 genera are endemic.  In China there are about 110 species of 11 genera which mostly occur in Guangxi, Guangdong and Yunnan; 58 species and more than 9 genera occur in the mountainous districts of Yunnan.   Moreover,  one  genus (Manglietiastrum Law, 1979) and 19 species are endemic to this region.  The family in discussion is much limited to or interruptedly distributed in the mountainous regions of Guangxi, Guangdong and Yunnan.  The regions are found to have a great abundance of species, and the members of the relatively primitive taxa are also much more there than in the other regions of the world.      The major genera, Manglietia, Magnolia and Michelia, possess 160 out of a total of 240 species in the whole family.  Talauma has 40 species, while the other eleven genera each contain only 2 to 7 species, even with one monotypic genus.   These three major genera are sufficient for indicating the evolutionary tendency and geographical distribution of Magnoliaceae.  It is worthwhile discussing their morphological  characters  and distributional patterns as follows:      The members of Manglietia are all evergreen trees, with flowers terminal, anthers dehiscing introrsely, filaments very short and flat, ovules 4 or more per carpel.  This is considered as the most primitive genus in subtribe Manglietiinae.  Eighteen out of a total  of 35 species of the genus are distributed in the western, southwest to southeast Yunnan. Very primitive species, such as Manglietia hookeri, M. insignis  and M. mega- phylla, M. grandis, also occur in this region. They are distributed from Yunnan eastwards to Zhejiang and Fujian through central China, south China, with only one species (Manglietia microtricha) of the genus westwards to Xizang.  There are several species distributing southwards from northeast India to the Malay Archipelago (Fig. 7).      The members of Magnolia are evergreen and deciduous trees or shrubs, with flowers terminal, anthers dehiscing introrsely or laterally, ovules 2 per carpel, stipule adnate to the petiole.  The genus Magnolia is the most primitive in the subtribe Magnoliinae and is the largest genus of the family Magnoliaceae. Its deciduous species are distributed from Yunnan north-eastwards to Korea and Japan (Kurile N. 46’) through Central China, North China and westwards to Burma, the eastern Himalayas  and northeast India.  The evergreen species are distributed from northeast  Yunnan  (China)  to  the Malay Archipelago.  In China there are 23 species, of which 15 seem to be very primi- tive, e.g. Magnolia henryi, M. delavayi, M. officinalis and M. rostrata, which occur in Guangxi, Guangdong and Yunnan.      The members of Michelia are evergreen trees or shrubs, with flowers axillary, an- thers dehiscing laterally or sublaterally, gynoecium stipitate, carpels numerous or few. Michelia is considered to be the most primitive in the subtribe Micheliinae, and is to the second largest genus of the family.  About 23 out of a total of 50 species of this genus are very primitive, e.g. Michelia sphaerantha, M. lacei, M. champaca,  and  M. flavidiflora, which occur in Guangdong, Guangxi and Yunnan (the distributional center of the family under discussion)  and extend eastwards to Taiwan  of  China, southern Japan through central China, southwards to the Malay Archipelago through Indo-China. westwards to Xizang of China, and south-westwards to India and Sri Lanka (Fig. 7).      The members of Magnoliaceae are concentrated in Guangxi, Guangdong and Yunnan and radiate from there.  The farther away from the centre, the less members we are able to find, but the more advanced they are in morphology.  In this old geographical centre there are more primitive species, more  endemics  and  more monotypic genera. Thus it is reasonable to assume that the region of Guangxi, Guangdong and Yunnan, China, is not only the centre of recent distribution, but also the chief survival centreof Magnoliaceae in the world.  相似文献   

11.
 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   

12.
This paper is here presented as a material for a flora of the Chinese grasses.  At the beginning, it chronologically gives a brief historical sketch on the study of the sub- tribe Isachninae.  The category which this group should constitute is here delimited, and its position in the natural system of grass-classification is also discussed.       Secondly it deals with a taxonomic treatment on the genus Isachne which comprises 16 species and 7 varieties in China, amongst which two species (I. hoi and I. hainanensis) and four varieties (I. albens var. glandulifera, I. truncata vars. crispa & maxima, and I. nipponensis var. kiangsiensis) are published here as new to science.  In addition, a new combination, I. hirsuta, (Hook. f.) Keng, f., based upon I. albens var. hirsuta Hook. f., is made here.  The two species (I. ciliatiflora Keng, and  I. tenuis  Keng)  published in Chinese only in the “Flora Illustralis Plantarum Primarum Sinicarum Graimeae 1959”, arehere supplemented with Latin diagnoses for validation.  相似文献   

13.
中国绞股蓝属(葫芦科)的研究   总被引:2,自引:0,他引:2  
 The genus Gynostemma B1. consists of 13 species and 2 varieties in the whole world, among which 11 species and 2 varieties occur in China. They are distributed in S. Shaanxi and the southern part of the Yangtze River (including Taiwan province) in China and also in Korea, Japan, Sri Lanka, India and Malesia. Based on the characters and dehiscence of fruit, the genus Gynostemma B1. may be divided into two subgenera, i.e. Subgen. I. Gynostemma and Subgen. II. Trirostllum (Z. P. Wang et Q. Z. Xie) C. Y. Wu ct S. K. Chen, comb. nov.        1.  Subgenus Gynostemma. The fruits are baccate, globose, 3-umbonate and incorni culate on the apical side, indehiscent when mature. The style apex in female flower is bifid.       Type of subgenus: Gynostemma pentaphyllum (Thunb.) Mak.       This subgenus contains 8 species and 2 varieties in the world, among which 6 speci- es and 2 varieties occur in China, i.e.1.G. simplicifolium B1. (Yunnan, Hainan of Guang- dong); 2. G. laxum (Wall.) Cogn. (S. Yunnan, Hainan of Guangdong and Guangxi); 3. G. burmanicum King ex Chakr. (Yunnan), 3a. G. burmanicum var. molle C. Y. Wu (Yun- nan); 4. G. pentaphyllum (Thunb.) Mak. (S. Shaanxi and the soutern area of the Yangtze River of China), 4a. G. pentaphyllum (Thunb.) Mak. var. dasycarpum C. V. Wu (Yun- nan); 5. G. pubescens (Gagnep.) C. Y. Wu, st. nov. (Yunnan); 6. G. longipes C. Y. Wu, sp. nov. (endemic to China: Yunnan, Sichuan, Guizhou, Shaanxi and Guangxi).       2.  Subgenus Trirostellum (Z. P. Wang et Q. Z. Xie) C. Y. Wu et S. K. Chen, comb. nov.——Trirostellum Z. P. Wang et Q. Z. Xie in Acta Phytotaxonomia Sinica 19 (4): 483. 1981, syn. nov. The fruit are capsules, subcampanulate, 3-corniculate on the apical side, dehiscent when mature. The style apex in female flower is luniform and irregularly denticulate at margin, rarely bifid.       Type of subgenus: Gynostemma cardiospermum Cogn. ex Oliv.      This subgenus comprises 5 species, which are all endemic to China.  1. G. yixingense (Z. P. Wang et Q. Z. Xie) C. Y. Wu et S. K. Chen (Jiangsu and Zhejiang); 2. G. cardio spermum Cogn. ex Oliv. (Hubei, Shaanxi and Sichuan); 3. G. microspermum C. Y. Wu et S. K. Chen (S. Yunnan); 4. G. aggregatum C. Y. Wu et S. K. Chen (NW. Yunnan); 5. G.laxiflorum C. Y. Wu et S. K. Chen (Anhui).  相似文献   

14.
 藤山柳属Clematoclethra(猕猴桃科)是中国特有属之一。本文作者研究了该属植物的   外部形态,统计了473张标本,结合地理分布,得出本属是一个单种属,并且是一个多型种的结   论。此种分为4个亚种。这与中国植物志的作者将本属分为20种和4变种不同。  本文作者   虽强调标本室分类是生物系统学研究的基础,是必不可少的一步,但这种分类,其方法上必须   根据大量标本,从研究性状变异开始,然后确定各分类群的划分和等级,最后才根据植物命名   法规的模式方法,给予它们正确名称。作者还根据本属的姊妹群猕猴桃属和它们的外类群水  东哥属的地理分布,推断本属是一个新特有属。  相似文献   

15.
对铁线莲属铁线莲亚属 Clematis subgen. Clematis 中的欧洲铁线莲 C. vitalba L.演化干的原始群威灵仙组sect. Clematis 进行了全面修订,确定此组共含有73种和45变种。写出了威灵仙组的分类学简史及地理分布;对威灵仙组中各亚组的亲缘和主要区别特征以及铁线莲亚属欧洲铁线莲演化干中各群的亲缘关系进行了讨论。将威灵仙组分为5个亚组,写出了分亚组检索表和各亚组的分种检索表,以及各种植物的形态描述、地理分布、生长环境等,并附有多幅插图。在5亚组中,欧洲铁线莲亚组(钝萼铁线莲亚组) subsect. Clematis 为此组的原始群,其主要特征:藤本;小叶通常草质或纸质,通常边缘具齿,有时全缘;萼片4,外面的毛长1 mm以下;花药长圆形、椭圆形或狭长圆形,稀条形,药隔顶端不突起,稀稍突起。此亚组的瘦果两侧扁压,但多数不扁平,不具边缘,只在短毛铁线莲 C. puberula Hook. f. & Thoms.强烈扁压,扁平,周围具宽边缘。在铁线莲属中,除短毛铁线莲外,特产朝鲜的 C. brachyura Maxim. (sect. Pterocarpa Tamura)也具有近似这种进化类型的瘦果。铁线莲组的其他4个亚组各含有较进化的特征,可能均自欧洲铁线莲亚组演化而出:单种的厚叶铁线莲亚组subsect. Crassifoliae (Tamura) Tamura为藤本;小叶革质,全缘,很像威灵仙亚组的小叶;雄蕊花丝皱缩,花药宽长圆形或长圆形。单种的长毛铁线莲亚组subsect. Baominianae (W. T. Wang) W. T. Wang为藤本;小叶纸质,具齿;花大,具6枚萼片;萼片外面的毛长1.6-3 mm; 花药长圆形。棉团铁线莲亚组subsect. Angustifoliae 的主要特征:茎直立;花常具5-6枚萼片。威灵仙亚组subsect. Rectae Prantl的主要特征:藤本,稀茎直立;小叶常革质,全缘,稀具齿;萼片通常4枚,稀较多,外面的毛长在1 mm以下;花药条形,有时狭长圆形,药隔顶端常突起。此亚组的威灵仙系ser. Rectae Prantl具有进化类型的瘦果,其瘦果强烈扁压,扁平,有膨胀的框状边缘。主要分类学处理为:(1)披针叶铁线莲 C. lancifolia Bur. & Franch.、准噶尔铁线莲 C. songarica Bunge、 C. ispahanica Boiss.、银叶铁线莲 C. delavayi Franch.和 C. phlebantha Williams 5种过去被Tamura和其他学者与灌木铁线莲 C. fruticosa Turcz.等同置于灌木铁线莲组sect. Fruticella Tamura中,但这5种的花构造(萼片水平方向开展,白色,边缘不展宽;花丝条形或狭条形)与灌木铁线莲(萼片斜上方开展,黄色,在花开放后边缘展宽成狭翅;花丝较宽,条状披针形)不同,而与棉团铁线莲 C. hexapetala Pall.的花构造相似。据此,本修订将此5种从灌木铁线莲组移到威灵仙组的棉团铁线莲亚组subsect. Angustifoliae Tamura中。(2)在欧洲铁线莲群 C. vitalba group与威灵仙群C. flammula group之间有不少过渡类型,因此,这两个群不易区分。根据这种情况,本修订将这两个群作为亚组处理,同置于威灵仙组sect. Clematis 中,而未采用Tamura和Grey_Wilson将这两个群分别置于两个亚属中,以及Johnson将这两个群分别置于两个组中的分类学处理。描述了2新系、6新种和1新变种;建立了5个新等级。  相似文献   

16.
笔者曾在1994年发表的“兰科植物区系中一些有意义属的地理分布格局的研究”一文中介绍了 此新亚属——显柱舌唇兰亚属的分布格局及其与舌唇兰亚属的区别。现将它正式发表。此新亚属含12种,其中1种为新组合种。  相似文献   

17.
The present paper describes the pollen morphology of 30 species belonging to 7 genera of Plumbaginaceae from China.  The pollen grains were all examined under light microscope, and those of some species under scanning and transmission electron microscope.       The pollen grains of the family are subspheroidal, prolate or oblate, (37.5-74.5)× (40.4-81.9)μ in size, 3-colpate, rarely 4-6-colpate,  only pancolpate in  Ceratostigma willmottianum.  The exine 2-layered, 2.0-7.4μ thick, sexine thicker than nexine, verrucate, reticulate or coarsely reticulate.       On the basis of the morphology, two types of pollen grains are distinguished in the family:       (1)  The pollen grains are 3-(rarely 4-6 ) or pancolpate, the exine verrucate. They are found in the tribe Plumbagineae (inculuding the genera Ceratostigma, Plumbago and Plumbagella).       (2)  The pollen grains are all 3-colpate, the exine reticulate or coarsely reticulate. They are found in the tribe Staticeae (including the genera Acantholimon, Ikonnikovia, Goniolimon and Limonium ).  相似文献   

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