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1.
2.
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   

3.
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   

4.
The morphological characters in the genus Orobanche were evaluated from the taxonomic point of view.  The author finds that the plants of this genus are relatively similar to each other in respect to characters of vegetative organs, fruits and seeds.  But the differences in the floral structures can be served as a basis for delimitating infrageneric taxa.   The seed coat of 18 species and pollen grains of  6 species were also examined under scanning electron microscope (SEM). They seem to have little significance for distinguishing species.       The result supports G. Beck’s (1930) division of the genus Orobanche into 4 sections, of which 2 occur in China, based on the characters of the inflorescence, bracteoles and calyx. The author considers that some characters, such as anther hairy or not, upper lip of corolla entire or not, lower lip longer or shorter than the upper one, the state of corolla-tube inflec-  tion and the hair type of filaments and plants, are important in distinguishing Chinese species.  A key to the species of Orobanche in China is given.       This genus consists of about 100 species, and is mostly confined to Eurasia, with over 60  species found in Caucasus and Middle Asia of USSR, where may be the mordern  distribu-  tional  centre.        Orobanche L. in China is represented by 23 species, 3 varieties and l forma. As shown in  Table 1, most species (12 species) are found in Xinjiang, which clearly shows a close floristic  relationship between this region and Middle Asia of USSR.  6 species are endemic to China,  of which 4 are confined to the Hengduan Mountains  (Yangtze-Mekong-Salwin divide).        The relationships between this genus and related ones of Orobanchaceae are also discussed.  The author holds the following opinions: the genus Phelypaea Desf. should be considered as a   member of Orobanche L. Sect. Gymnocaulis G. Beck,  the monotypic genus,   Necranthus A.   Gilli endemic to Turkey, is allied with Orobanche L. Sect.  Orobanche, the monotypic genus,   Platypholis Maxim, endemic to Bonin Is. of Japan, is far from Orobanche L. in relation and   should be regarded as a separate genus.        The 11 OTU’s, including all the sections of Orobanche L. and 7 genera of Orobanchaceae,   and 15 morphological characters were used in the  numerical  taxonomic treatment  to  test  the   above-mentioned  suggestions.   After standardization of characters, the correlation matrices were   computerized.  The correlation matrices were made to test the various clustering methods.   At    last the UPGMA clustering method was chosen and its result is shown in a phenogram.  The   result of numerical analysis is basically in accordance with the suggestions.  相似文献   

5.
我国悬钩子属植物的研究   总被引:1,自引:0,他引:1  
 The genus Rubus is one of the largest genera in the Rosaceae, consisting of more than 750 species in many parts of the world, of which 194 species have been recorded in China.      In the present paper the Rubus is understood in its broad sense, including all the blackberries, dewberries and raspberries, comprising the woody and herbaceous kinds. So it is botanically a polymorphic, variable and very complicated group of plants. The detailed analysis and investigation of the evolutionary trends of the main organs in this genus have indicated the passage from shrubs to herbs in an evolutionary line, although there is no obvious discontinuity of morphological characters in various taxa. From a phylogenetic point of view, the Sect. Idaeobatus Focke is the most primitive group, characterized by its shrub habit armed with sharp prickles, aciculae or setae, stipules attached to the petioles, flowers hermaphrodite and often in terminal or axill- ary inflorescences, very rarely solitary, druplets separated from receptacles. Whereas the herbaceous Sect.  Chamaemorus L. is the most advanced group, which is usually unarmed, rarely with aciculae or setae, stipules free, flowers dieocious, solitary, dru- plets adhering to the receptacles and with high  chromosome numbers  (2n = 56). Basing upon the evolutionary tendency of morphological  features,  chromosome nu- mbers of certain species recorded in literature and the distribution patterns of species, a new systematic arrangement of Chinese Rubus has been suggested by the present authors. Focke in his well-known monograph divided the species of Rubus into  12 subgenera, while in the Flora of China 8 sections of Focke were adapted, but some im- portant revisions have been made in some taxa and Sect. Dalibarda Focke has been reduced to Sect.  Cylactis Focke.  In addition, the arrangement of sections is presented in a reverse order to those of Focke’s system.  The species of Rubus in  China are classified into 8 sections with 24 subsections (tab. 3) as follows: 1. Sect. Idaeobatus, emend. Yü et Lu(11 subsect. 83 sp.); 2. Sect. Lampobatus Focke (1 sp.); 3. Sect. Rubus (1 sp.); 4. Sect. Malachobatus Focke, emend. Yü et Lu (13 subsect. 85 sp.); 5. Sect. Dalibardastrus (Focke)Yü et Lu (10 sp.); 6. Sect. Chaemaebatus Focke (5 sp.); 7. Sect. Cylactis Focke, emend. Yü et Lu (8 sp.); 8. Sect. Chamaemorus Focke (1 sp.).      In respect to the geographical distribution the genus Rubus occurs throughout the world as shown in tab. 2, particularly abundant in the Northern Hemisphere, while the greatest concentration of species appears in North America and E. Asia.  Of the more than 750 species in the world, 470 or more species (64%) distributed in North America.  It is clearly showm that the center of distribution lies in North America at present time.  There are about 200 species recorded in E. Asia, of which the species in China (194) amount to 97% of the total number. By analysis of the distribution of species in China the great majority of them inhabit the southern parts of the Yangtze River where exist the greatest number of species and endemics,  especially in south- western parts of China, namely Yunnan, Sichuan and Guizhou (tab. 3. 4.).  It is in- teresting to note that the centre of distribution of Rubus in China ranges From north- western Yunnan to south-western Sichuan (tab. 5), where the genus also reaches its highest morphological diversity.       In this region the characteristics of floristic elements of Rubus can be summarized as follows: it is very rich in composition, contaning 6 sections and 94 species, about 66% of the total number of Chinese species; there are also various complex groups, including primitive, intermediate and advanced taxa of phylogenetic importance; the proportion of endemic plants is rather high, reaching 61 species, up to 44% of the total endemics in China.  It is noteworthy to note that the most primitive Subsect. Thyrsidaei (Focke) Yü et Lu, consisting of 9 endemic species, distributed in southern slopes of the Mts. Qin Ling and Taihang Shan (Fig. 4). From the above facts we may concluded that the south-western part of China is now not only the center of distribu- tion and differentiation of Rubus in China, but it may also be the center of origin ofthis genus.  相似文献   

6.
 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   

7.
 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   

8.
9.
The first classification for the genus Ormosia was proposed by Bentham. It was followed by Taubert (1892) in Engler and Prantl’s Nat. Pflanzenf., who divided the genus into 2 sections.  On the basis of the pod structure and seed characters Prain (1900) arran- ged the genus in 2 sections with 4 subsections.  In the monograph on the genus Merrill and L. Chen ( 1943 ) limited their taxonomic study to Chinese and Indo-Chinese species, and recognized 34 species and 15 series.  Recently Yakovlev (1971-1976) has treated the ge- nus in 6 separate genera.      In the present paper the author recognizes 35 species, of which 7 species and 2 varie- ties are new.  The Chinese species of the genus are grouped into 3 sections and 6 series inmy classification.  相似文献   

10.
This paper deals with the taxa of tribe Arundinarieae Steud. subtribe Pleiobalastinae Keng and Keng f. which comprised three genera (Pseudosasa Makino, Pleioblastus Nakai and Brachystachyum Keng) when it was established in 1957. With the analysis of morphological characters and geographical distribution, a number of revisions connected with the taxon are made as follows:      (1)  Genus Brachystachyum Keng is transferred to the tribe Shibataeeae Nakai ac- cording to its false inflorescence.      (2)  Genus Pseudosasa Makino is transferred to subtribe Sasinae Keng f. according to our study on the numerical taxonomic method.      (3)  Some species of Pleioblastus Nakai established by Keng and Keng f. should be revised. Pleioblastus actinotrichus (Merr. and Chun) Keng f. should be Ampelocalamus actinotrichus (Merr. and Chun) S. L. Chen, T. H. Wen and G. Y. Sheng in subtribe Tham- nocalaminae Keng f.; Pleioblastus dolichanthus (Keng) Keng f. is the synonym of Sinobam- busa tootsik (Sieb.) Makino, belonging to tribe Shibataeeae Nakai. The rest species remain in this genus. Since the genus Pleioblastus is related to genus Arundinaria Michaux., subtribe Pleioblastus Keng and Keng f. does not seem to have a reason to be retained as a subtribe in tribe Arundinarieae Steud., according to the newest Code (1978). A part of it should be a synonym of subtribe Arundinariinae and we may cite it as follows: Subtribe Arundinariinae——Subtribe Pleioblastinae Keng and Keng f. pro parte, syn. nov. The other parts of it should be transferred to other subtribes or tribes.       In addition, one new variety in Branchystachyum, two new species, one new variety in Pseudosasa and six new species, three new varieties in Pleioblastus, are described in this paper.  相似文献   

11.
   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   

12.
A cytological study reveals the chromosome number of 2n=28 for Siraitia grosvenori (Swingle) C. Jeffrey ex Lu et Z. Y. Zhang from Yongfu County,  Guangxi  (fig. 1), which is different from the previous report of 2n=24 (Zou Qi-li et al. 1980).  The vou- cher is deposited in the herbarium of Commission for Integrated Survey of Natural Resources,Academia Sinica.  相似文献   

13.
When the genus  Yinshania Ma et Y.  Z. Zhao  was published,  it had only a single species, Y. albiflora Ma et Y.  Z.  Zhao which was indicated as the type of the genus (Acta Phytotax. Sin. 1979).  Y. Z. Zhao 155.  was indicated as the type specimen of Y.  albiflora. It is adequate to cite Y. albiflora Ma et Y.  Z. Zhao as the type of genus Yinshania Ma et Y. Z. Zhao. In a revision (Acta Phyto- tax.  Sin.  25(3): 204-219, 1987) Y.  H. Zhang made  a combintion,  Yinshania acutangula (O. E. Schulz) Y.  H. Zhang (=Cochlearia acutangula O. E. Schulz) and reduced Yinshania albiflora Ma et Y. Z. Zhao as a variety of Y. acutangula,i. e. Y. acutangula var. albiflora (Ma et Y. Z. Zhao) Y. H. Zhang. She is uncorrect, however, when she cited Y.  acutangula (O. E. Schulz) Y. H .  Zhang as the type of the genus Yinshania Ma et Y. Z. Zhao. It should be cited as follows: Yinshania Ma et Y. Z. Zhao      Typus generis: Yinshania albiflora Ma et Y. Z. Zhao (=Yinshania acutangula(O. E. Schulz) Y. H. Zhang var. albiflora (Ma et Y. Z. Zhao) Y. H. Zhang)  相似文献   

14.
 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   

15.
 本文报道了我国黑龙江产桔梗科沙参属的10种1变种的染色体数目和核型,对其中     7种作了减数分裂行为的观察。  其中6种1变种为首次报道,并发现2n=68的4x种。该     属染色体基数多为17(x=17),但Adenophora trachelioides和A.remotiflora的基数为18     (x=18),为该属独特基数。核型的共同特征是:小型,以中部(m)、近中部(sm)着丝点     染色体为主,至少具一对近端着丝点染色体和一对随体染色体。该属染色体的演化处于二种     水平:  数目变化(包括多倍化和非整倍体变化)和结构变异。  多倍化是该属物种形成的主要     途径之一。结合其它性状讨论了这些种的分类,并确立1个四倍体新种(A. amurica)和1个新组合(A.pereskiifolia ssp.alternifolia)。  相似文献   

16.
 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   

17.
The genus Cochleariopsis Y.H. Zhang was described in 1985, with C. zhejiangensis Y. H. Zhang, the only member of the genus, as its type. However, this species had been published by O.E. Schulz earlier in 1923, named Cochlearia warburgii O.E. Schulz. Hence, this species is not new one, and the type of the ge-nus should be Cochleariopsis warburgii (O. E. Schulz)L. L. Lu .  相似文献   

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