鄂西神农架地区的植被和植物区系

 Shennungia is generally known as “The highest mountain in Central China”. It is situated at latitude 31°342'N., longitude 110°35'E. in western Hupeh.       The area explored is deeply cut in all sides by five V-shaped valleys, giving the landscape a steep topography.  Its summit is about 3105 meters above the sea level, and the relative altitude is from 1000-2000 meters.      The climate of the region is warm temperate.  The differences of humidity-warmth condition between the eastern and the western flanks are quite marked.      In western Hupeh and the adjacent area of Szechuan the rugged topography still preserves some tracts of natural forests at higher elevations.  Our vegetational survey is confined to localities above 1500 meters. The collection of plant samples of the flora is extended to the whole mountain from the foothill to the peak.  The present article deals with only a part of the results of our survey.      1.  The vertical vegetation belts of Mt. Shennungia and relationships with other regions:  The vegetation belts on the eastern and the western flanks of the mountain are shown in diagram 2 and 3.  The comparison of the vertical vegetation zones of the Mt. Shennungia with those of the Yülungshan in N. W. Yunnan and the eastern Himalaya to the west and with those of Hwangshan and Central Japan to the east is shown in table 4, It shows that the plant communities of the Mt. Shennungia are of temperate nature, and they are more closely related to those of Hwangshan in S. Anhwei and of Central Japan than to the eastern Himalaya.      2.  Floristic composition: The generic ranges of flowering plant are relatively distinct and stable. Various distributional patterns of genera are analysized.      1)  Statistics of the genera in various distributional patterns: The total number of genera of flowering plants in this region are 762, belonging to the following four categories. A) tropical genera 239 (31.3%), B)  temperate  genera  416 (54.7%),  C) endemic genera 47 (6%), and D) comsmopolitan genera 61 (8%).       2)  Endemic genera:  An examination of the composition of the flora in western Hupeh reveals that 47 endemic Chinese genera occur in this mountain of which 24 are monotypic genera, 20 oligotypic and 2 multitypic as shown in Table 4. The arborescent genera are nearly all deciduous. They are of temperate nature.       3)  Temperate genera:  There are 416  genera in  wastern Hupeh.  They  are subdivides into the following three groups according to their distributional patterns: A)  The north temperate genera: There are 159 genera belonging to 62 families in western Hupeh. B)  Eastern Asian genera:  There are 117 genera belonging to 69 families in western Hupeh.  Among them 22 are common to the western Szechuan, adjacent regions of Yunnan and the Eastern Himalaya.  The remaining 95 genera are commom to both eastern China and Japan. C) The Eastern Asian-eastern North- American genera:  Of the total 762 genera known in western Hupeh, 64 are disjunc- tively distributed in both eastern Asia and eastern North-America.       4)  The tropical genera: Of the 762 genera of the flowering plant of western Hupeh, 239 (31%) are of tropical nature.       Finally, our survey shows:  1. Many of the primitive temperate genera and ende- mic relicts concentrate in western Hupeh and the adjacent region of Szechuan indica- ting that it might be one of refuges of tertiary flora. Moreover, it might also be one of the most important regions of differentiation, development and distribution of tem- perature flora. 2.  The vegetation of this region is not only of temperate nature, but also of a transitional nature. 3.  According to an analysis of the flora and a compari- son of the vertical distribution of the vegetation of Yülungshan and Eastern Himalaya to the west with Hwangshan and Central Japan to the east, the floristic affinity of western Hupeh is more closely related to eastern China and Central Japan rather than to the Eastern Himalaya, and phytogeographically this region is intermediate between the Sino-Himalayan and the Sino-Japanese patterns.  However, the problem of phyto- geography of western Hupeh and the adjacent region of Szechuan is a complicated one requiring further study.       

河北涞源县的古油松化石

   The fossils here described were collected from the Lai Yuan, Hebei Province in north China.  Well-preserved plant parts are cones of Pinus, identified as Pinus pro- totabulaeformis sp. nov.  The species is different from other taxa of Pinus by larger cones and scales.  The size of the cone is a reliable diagnostic character in the group: The large cone and scale indicate rather an arid climate in Summer in the region where the fossils are discovered.      The age of bearing-beds is considered Upper Eocene-Lower Oligocene.      Diagnosis:  Cones ovate in general outline, 8.5 cm long, 4.5 cm in diameter. Seed scales oblong, 2—2.5 cm long, 0.8—1.1 cm wide.   Apophysis  obviously  fattened  andthickned, convex, compressed rhomboid, rostrate at the apical part of seed-bract.     

木兰科分类系统的初步研究

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.     

西藏菊科植物

 1)  The Compositae in Tibet so far known comprise 508 species and 88 genera, which nearly amounts to one fourth of the total number of genera and one third of the total number of species of Compositae in all China, if the number of 2290 species and 220 genera have respectively been counted in all China. In Tibet there are all tribes of Com- positae known in China, and surprisingly, the large tribes in Tibetan Compositae are also large ones in all China and the small tribes in Tibet are also small ones in all China. Generally speaking, the large genera in Tibet are also large ones in all China and the small genera in Tibet are likewise small ones in all China. In this sense it is reasonable to say that the Compositae flora of Tibet is an epitome of the Compositae flora of all China.      In the Compositae flora of Tibet, there are only 5 large genera each containing 30 species or more. They are Aster, Artemisia, Senecio, Saussurea and Cremanthodium. And 5 genera each containing 10—29 species. They are Erigeron, Anaphalis, Leontopodium, Ajania, Ligularia and Taraxacum. In addition, there are 77 small genera, namely 87% of the total of Compositae genera in Tibet, each comprising 1—9 species, such as Aja-niopsis, Cavea and Vernonia, etc.      2)  The constituents of Compositae flora in Tibet is very closely related to those of Sichuan-Yunnan provinces with 59 genera and 250 species in common. Such a situation is evidently brought about by the geographycal proximity in which the Hengtuang Shan Range links southeastern and eastern Tibet with northern and northwestern Sichuan- Ynnnan.  With India the Tibetan Compositae have 59 genera and 132 species in common, also showing close floristic relationships between the two regions. Apparently the floris- tic exchange of Compositae between Tibet and India is realized by way of the mountain range of the Himalayas.  The mountain range of the Himalayas, including the parallel ranges, plays a important role as a bridge hereby some members of the Compositae of western or northern Central Asia and of the northern Africa or of western Asia have migrated eastwards or southeastwards as far as the southern part of Fibet and northern part of India, or hereby some Compositae plants of eastern and southeastern Asia or Asia Media have migrated northwestwards as the northern part of Central Asia.      Some of the species and genera in common to both Tibet and Sinjiang indicate that this weak floristical relationship between these regions is principally realized through two migration routes: one migration route is by way of the Himalayas including the parallel ranges to Pamir Plataeu and Tien Shan, or vice versa. The other migration route is by way of northern Sinjiang to Mongolia, eastern Inner Mongolia, southwards to Gansu, Qinghai (or western Sichuan), eastern Tibet up to the Himalayas, or vice versa.      However, Tibet is not entirely situated at a migration crossroad of the floral ele- ments. An ample amount of the data shows that Compositae flora have a particular capability of development in Tibet. of the total number of species of Tibetan Com- positae, 102 species and 1 genus (Ajaniopsis Shih) are endemic. Besides, 8 genera are re- gional endemics with their range extending to its neighbourhood. The higher percentage of endemics at specific level than at generic in Tibetan Compositae may be a result of active speciation in response to the new enviromental conditions created by the uplifting of the Himalayas.  The flora in Tibetan Plateau as a whole appears to be of a younger age.       3) The uprising of the Himalayas and of the Tibetan Plateau accompanied by the ultraviolet ray radiation, the microthermal climate and the high wind pressure has, no doubt, played a profound influence upon the speciation of the native elements of Tibetan Compositae. The recent speciation is the main trend in the development of the Com-positae flora native in Tibet in the wake of upheaval of the plateau.     

西藏豆科植物区系的形成与分化

 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.     

中国种子植物特有属的数量分析

Chinese flora with many endemic elements is highly important in the world’s flora. According to recent statistics there are about 196 genera of spermatophytes, be- ing 6.5% of total Chinese genera.  These endemic genera comprising 377 species belong to 68 families, among which the Gesneriaceae (28 genera), Umbelliferae (13), Compo- sitae (13), Orchidaceae (12) and Labiatae (10) are predominant.  The tropical type containing 24 families and 80 genera is dominant. After it follows the temperate type with 23 families and 50 genera.  There are also 4 families endemic to China, i.e. Gin- kgoaceae, Bretschneideraceae, Eucommiaceae and Davidiaceae.  It shows that genera endemic to China are obviously related to the tropical and temperate flora in essence.      The endemic monotypic genera (139) and endemic obligotypic genera (48) combin- ed make up more than 95% of the total number of genera endemic to China.  Phylo- genetically more than half of them are ancient or primitive.  The life forms of all ende- mic genera are also diverse.  Herbs, especially perennial herbs, prevail with the propor- tion of about 62%, and trees and shrubs are the next, with 33%, and the rest are lianas.       Based upon the calculated number of genera endemic to China in each province and the similarity coefficents between any two provinces, some conclusions may be drawn as follows:       Yunnan and Sichuan Provinces combined are the distribution centre of genera en- demic to China and may be their original or  differentiation area,  because  numerous endemic genera, including various groups, exist in these two provinces.  The second is Guizhou where there are 62 endemic genera.  Others form a declining order, south China, central China and east China. But towards the north China endemic genera de- crease gradually, and the Qinling Range is an important distributional limit.       The largest simitarity coefficient, over 50%, appears between Shaanxi and Gansu probably because of the Qinling Range linking these two provinces.  But between any other two provinces it is less than 30% and it is generaly larger between two south pro- vinces than between two north provinces.       These characteristics mentioned above are correlated with topography and climate, and they may be resulted from the diversification in geography and climatic influence for a long time.     

论胡桃科植物的地理分布

 The present paper aims to discuss the geog raphical distribution of the Juglandaceae on the basis of unity of the phylogeny and the process of dispersal in the plants.       The paper is divided into the following three parts:       1.  The systematic positions and the distribution patterns of nine living genera in the family Juglandaceae (namely, Engelhardia, Oreomunnea, Alfaroa, Pterocarya, Cyclo- carya, Juglans, Carya, Annamocarya and Platycarya) are briefly discussed.  The evolu- tional relationships between the different genera of the Juglandaceae are elucidated. The fossil distribution and the geological date of the plant groups are reviewed.  Through the analysis for the geographical distribution of the Juglandaceous genera, the distribu- tion patterns may be divided as follows:       A.  The tropical distribution pattern       a. The genera of tropical Asia distribution: Engelhardia, Annamocarya.       b. The genera of tropical Central America distribution: Oreomunnea, Alfaroa.       B.  The temperate distribution pattern       c. The genus of disjunct distribution between Western Asia and Eastern Asia: Pterocarya.       d. The genus of disjunct distribution between Eurasia and America: Juglans.      e. The genus of disjunct distribution between Eastern Asia and North America: Carya.      f. The genera whose distribution is confined to Eastern Asia: Cyclocarya, Platy- carya.      2.  The distribution of species      According to Takhtajan’s view point of phytochoria, the number of species in every region are counted.  It has shown clearily that the Eastern Asian Region and the Coti- nental South-east Asian Region are most abundant in number of genera and species. Of the 71 living species, 53 are regional endemic elements, namely 74.6% of the total species. The author is of the opinion that most endemic species in Eurasia are of old endemic nature and in America of new endimic nature.  There are now 7 genera and 28 species in China, whose south-western and central parts are most abundant in species, with Pro- vince Yunnan being richest in genera and species.      3.  Discussions of the distribution patterns of the Juglandaceae A.       The centre of floristic region B.         The centre of floristic regions is determined by the following two principles:  a. A large number of species concentrate in a district, namely the centre of the majority; b.  Species of a district can reflect the main stages of the systematic evolution of the Juglandaceae, namely the centre of diversity.  It has shown clearly that the southern part of Eastern Asian region and the northern part of Continental South-east Asian Region (i.c. Southern China and Northern Indo-China) are the main distribution centre of the Juglandaceae, while the southern part of Sonora Region and Caribbean Region  (i.c. South-western U.S.A., Mexico and Central America) are the secondary distribution centre.       As far as fossil records goes, it has shown that in Tertiary period the Juglanda- ceae were widely distributed in northern Eurasia and North America, growing not only in Europe and the Caucasus but also as far as in Greenland and Alaska.  It may be considered that the Juglandaceae might be originated from Laurasia.  According to the analysis of distribution pattern for living primitive genus, for example, Engelhar- dia, South-western China and Northern Indo-China may be the birthplace of the most primitive Juglandaceous plants.  It also can be seen that the primitive genera and the primitive sections of every genus in the Juglandaceae have mostly distributed in the tropics or subtropics. At the same time, according to the analysis of morphological cha- racters, such as naked buds in the primitive taxa of this family, it is considered that this character has relationship with the living conditions of their ancestors.  All the evidence seems to show that the Juglandaceae are of forest origin in the tropical moun- tains having seasonal drying period.       B.  The time of the origin       The geological times of fossil records are analyzed. It is concluded that the origin of the Juglandaceae dates back at least as early as the Cretaceous period.       C.  The routes of despersal       After the emergence of the Juglandaceous plant on earth, it had first developed and dispersed in Southern China and Indo-China.  Under conditions of the stable tempera- ture and humidity in North Hemisphere during the period of its origin and development, the Juglandaceous plants had rapidly developed and distributed in Eurasia and dis- persed to North America by two routes: Europe-Greenland-North  America  route  and Asia-Bering Land-bridge-North America route.  From Central America it later reached South America.      D.  The formaation of the modern distribution pattern and reasons for this forma- tion.      According to the fossil records, the formation of two disjunct areas was not due to the origin of synchronous development, nor to the parallel evolution in the two con- tinents of Eurasia and America, nor can it be interpreted as due to result of transmis- sive function.  The modern distribution pattern has developed as a result of the tectonic movement and of the climatic change after the Tertiary period.  Because of the con- tinental drift, the Eurasian Continent was separated from the North American Conti- nent, it had formed a disjunction between Eurasia and North America. Especially, under the glaciation during the Late Tertiary and Quaternary Periods, the continents in Eu- rasia and North America were covered by ice sheet with the exception of “plant refuges”, most plants in the area were destroyed, but the southern part of Eastern Asia remained practically intact and most of the plants including the Juglandaceae were preserved from destruction by ice and thence became a main centre of survival in the North Hemisphere, likewise, there is another centre of survival in the same latitude in North America and Central America.      E.  Finally, the probable evolutionary relationships of the genera of the Juglanda-ceae is presented by the dendrogram in the text.     

中国白花丹科花粉形态研究

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 ).     

蔷薇科太行花属系统位置的研究

 We have described a new genus Taihangia, collected from, the south part of Taihang Mountain in northern China. At the same time, comparative studies on Taihangia with its related genera have been made in various fields including external morphology, anatomy of carpels, chromosome and pollen morphology by light, scanning and transmission electron microscope. In addition, isoperoxidases of two varietier were analysed by means of polya-crylamide gel slab electrophoresis. The preliminary results are as follows:       Morphology: The genus Taihangia is perennial and has simple leaves, occasionally with 1—2 very small reduced lobes on the upper part of petiole; flowers white, andromo- noecious and androdioecious, terminal, single or rarely 2 on a leafless scape; calyx and cpicalyx with 5 segments; petals 5; stamens numerous; pistils numerous, with pubescent styles, spirally inserted on the receptacle in bisexual flowers, but with less number of abortive and glabrous pistils in male flowers.       In comparison with the related genera such as Dryas, Geum, Coluria and Waldsteinia, the new genus has unisexual flowers and always herbaceous habit indicating its advanced feature but the genus has a primitive style with thin and short hairs as compared with the genus Dryas which has long, pinnately haired styles, a character greatly facilitamg anemo-choric dissemination. The styles of Taihangia are slender and differ from those of the ge-nus Geum which are articulate, with a persistent hooked rostrum, thus adapting to epizo-ochoric dissemination to a higher degree.       The anatomy of carpels shows the baral position of ovules in the genus Taihangia like those in other related genera such as Dryas, Geum, Acomastylis, Coluria and Waldsteinia. This suggests that the new genus and its related ones are in a common evolutionary line as compared with the other tribes which have a pendulous ovule and represent a separate evolutionary line in Rosaceae. Dorsal and ventral bundles in carpels through sections are free at the base. Neither fusion, nor reduction of dorsals and vertrals. are observed. This shows that the genus Taihangia is rather primitive.       Somatic chromosome: All the living plants, collected from both Honan and Hopei Provinces were examined. The results show that in these plants the chromosome number is 2n= 14, and thus the basic number of chromosome is x=7. Such a diploid genus is first found in both anemochoric and epizoochoric genera. Therefore, in this respect Taihangia is primitive as compared with herbaceous polyploid genus Geum and related ones.      Pollen: The stereostructure shown by scanning electron microscope reveals  that  the pollen grains of the genus Taihangia are ellipsoid and 3-colporate. There are two types of exine sculpture. One is rather shortly striate and it seems rugulate over the pollen surface; the other is long-striate. The genus Dryas differs in having only short and thick striae over the surface. The genus is similar to the genera Geum, Coluria and Waldsteinia in colpustype, but differs from them in that they all have long, parallel striae which are distributed along the meridional line.       In addition, under transmission electron microscope, the exine in the Taihangia and related genera Acomastylis, Geum, Coluria, Waldsteinia and Dryas has been shown to be typically differentiated into two distinct layers, nexine and sexine. The nexine, weakly statined, appears to consist of endoxine with no foot-layer, in which the columellae are fused, and which is thicker beneath the apertures. The sexine is 2-layered, consisting of columellae and tectum. Three patterns of tectum can be distinguished in the tribe Dryadeae: the first, in the genera Taihangia, Acomastylis, Geum, Coluria and Waldsteinia, is tectate-imperforate, with the sculpturing elements both acute and obtuse at the top and broad at the base; the second, in the genus Dryas, is semitectate, with the sculpturing elements shown in ultrathin sections rod-like and broader at the top than at the base or as broad at the top as at the base, and the third, tectate-perforate, with the sculpturing elements different in size. From the above results, the herbaceous groups and woody ones  have palynologically evolved in two distinct directions, and the genus Taihangia is related to other herbaceous genera such as Acomastylis, Geum, Coluria and Waldsteinia, as shown in the electron microphotographs of ultrathin sections. The genus Taihangia, however, is different from related herbaceous genera in that the pollen of Taihangia is dimorphic, i.e. in addition to the above pattern of pollen another one of the exine in Taihangia is rugulate, with the sculpturing elements shown in the ultrathin sections being obtuse or emarginate and nearly as broad at the top as at the base.      The interesting results obtained from the comparative analysis of morphology, ana- tomy of carpels, chromosome countings, microscopic and submicrosocopic structures of pollen may enable us to evaluate the systematic position of Taihangia and to throw a new light on evolution of the tribe Dryadeae. It is well known that the modes of dissemination of rosaceous fruits play an important role in the expansion and evolution of the family. The follicle is the most primitive and the plants with follicles, like the Spiraeoideae, are mostly woody and mesic, while the achene, drupe and pyrenarium are derived. In Rosoideae  having a achene is a common feature. Particularly in the tribe Dryadeae, which is distinguished from the other related tribes by having orthotropous ovules, the methods of dissemination of fruits have developed in three distinct specialized directions: anemochory with long, plumose styles (e.g. Dryas), formicochory or dispersed by ants or other insects, with the deciduous styles (e.g. Waldsteinia and Collria),and epizoochory with the upper deciduous stigmatic part and the lower persistent hooked rostrum, an  adhesive organ favouring  epizoochory dissemination (e. g. Geum and related taxa). Taihangia is a genus endemic to mesophytic forest area of northern China. Due to its narrow range and specific habit as well as pubescent styles, neither perfectly adapted to anemochory nor to epizoochory, the genus  Taihangia might be a direct progeny of the ancestry of anemochory. Maintaining the diploidy and having an ntermediate sculptural type of pollen, the new genus might probably represent a linkage between anemochory and zoochory (including epizoochory and dispersed by ants).       Experimental evidence from isoperoxidases shows the stable zymograms of root and roostoks. The anodal isozyme of T. rupestris var. rupestris may be divided into 6 bands: A, B, C, D, E, F, and T. rupestris var. ciliata into 4 bands: A, B, C, G. The two varietiesof the species share 3 bands: A, B, C. However, D, E and F bands are characteristic of var. rupestris and G band is limited to var. ciliata. As far as the available materials are concerned, the analysis of isoperoxidases supports the subdivision of the species into two varieties.     

星果草属、独叶草属、鸡爪草属的染色体观察和系统位置的探讨

1.  The present paper describes the observations of chromosome  numbers  and karyomorphology of 2 species of 2 endemic genera and I endemic species of Chinese Ranunculaceae: Asteropyrum peltatum (Franch.)  Drumm et Hutch. 2n=16, x=8; Kingdonia unifolia Balf. f. et W. W. Sm. 2n=18, x=9 and Calathodes oxycarpa Spra- gue 2n=16, x=8.  The chromosome counts of three ranunculaceous genera are repor- ted for the first time.       2.  The morphylogical, palynological and cytological date in relation to the syste- matic postition of Asteropyrum, Kingdonia and Calathodes within the family Ranun- culaceae are diseussed and resulted in following conclusions:       (1).  On the basis of the basic number x=8 in Asteropyrum, it is further con- firmed that this genus is distinct from the r elated genera such as Isopyrum, Dichocarp- um and other allied taxa.       The comparison of Asteropyrum with Coptis shows that they are identical in short chromosomes, with magnoflorina and benzylisaquinodine type of alkaloides, but dif- ferent from coptis in the chromosome numbers (T-type), pantocolpate pollens, united carpels and the dorsi-ventral type of petioles.  In view of these fundamental morpho- logical and cytological differences, Asterop yrum is better raised to the level of Tribe. However Asteropyrum and Coptis may represent two divaricate evolutional lines of Thalictroideae.       (2).  The systematic position of the genus Kingdonia has been much disputed in the past.  We support the view of Sinnote (1914), namely, the trilacunar in leaf traces “the ancient type”, appeared in the angiosperm line very early, while the uni- lacunar of Kingdonia may be derived from the trilacunar.  On the basis of the chromo- some numbers and morphylogical observation, the present writer accept Tamura’s and Wang’s treatment by keeping Kingdonia in Ranunculaceae instead of raising it to a family rank as has been been done by Forster  (1961).  Kingdonia and  Coptis are similar in having short chromosome with x=9, but with one-seeded fruits; therefore it is suggested that placed into Thalictroideae as an independent tribe, indicating its close relationship with Coptideae.        (3).  Comparing with its allies, Calathodes being with out petals, seems to be more  primitive than Trollius. But Calathodes differs from Trollius with R-type chromosomes in having T-type chromosome with x=8 and subterminal centromere.  Those charac- teristics show that it is very similar to the related genera of Thalictroideae.  But as Kurita already pointed out that most speci es of Ranunculus have usually large long chromosomes but some species have compar ativelly short chromosomes, therefore we regard T-type and R-type chromosomes appear independently in different subfamilies of Ranunculaceae. According to Tamura, G alathodes seems to be  closely related  to Megaleranthis, because of the resemblance in follicles.  But due to lack of cytological data of the latter genus, the relationship between the two genera still is not clear pen- ding further studies. From the fact that the  morphology and  chromosomes  of  the Calathodes differs from that of all other genera of the Helleboroideae, we consider Calathodes may form an independent tribe of its own with a closer relationship withTrollieae.     

罗汉果属修订及葫芦科二新属

   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。     

武夷山苔藓植物区系及其与邻近地区的关系

本文结合地史初步探讨了第三纪以来武夷山苔藓植物可能发生的变化。武夷山的苔藓     植物主要为东亚区系成分和旧热带区系成分，与泛北极区系成分的相似性也相当明显。东亚     特有属(5个)系组成武夷山苔藓植物区系的重要因素之一，它低于黄山和西天目山的9个和     7个，与黄山等组成一个共同的苔藓植物东亚特有属的分布中心。从各方面的分析推测，这    类植物可能起源于第三纪，系一类“孑遗植物”。     

胡桃目的分化、进化和系统关系

本文所讨论的胡桃目的概念包括胡桃科和马尾树科。作者详细地对该类群植物性的分化，果实 传播方式及分化，生态及地理的分化等方面进行了较系统的分析，最后探讨了该目的系统位置，认为胡桃目与杨梅目和山毛榉目有密切的联系，是金缕梅类植物演化最高级的一个类群。     

密叶杉属的核型分析及其系统位置的探讨

本文首次对特产澳大利亚塔斯马尼亚岛的Athrotaxis cupressoides和Athrotaxis selaginoides进行了核型分析，核型公式分别为2n=22=22m(2SAT)和2n=22=20(2SAT)+2sm，均属Stebbins的1B类型，它们的染色体相对长度组成为22=2L+10M2+8Ml+2S和22=2L十10M2+6Ml+4S，后者比前者较为进化。根据密叶杉属和杉科其他各属核型资料的比较分析，它们由原始到进步的顺序可能为：柳杉属、水松属、落羽杉属、水杉属、巨杉属、红杉属，密叶杉属、杉木属和台湾杉属。  密叶属与红杉属、巨杉属和杉木属较为近缘。  这些在以染色体长度比和平均臂比为纵、横坐标的图上得到清楚反映。  根据核型资料，密叶杉属以隶于单型的亚科Arthrotaxoideae较为合适，这也得到形态学、胚胎学、孢粉学和地理学资料的支持。  本文还对前人系统中的密叶杉属位置进行了讨论。     

落叶松属的核型及系统位置的研究

 本文分析了我国特产树种红杉Larix potaninii的核型，K(2n)=24=12m+8sm+4st，属2A类型，染色体相对长度组成为2n=24=4L+8M2+8M1+4S。落叶松属植物(10种)的核型由6对较长的中部着丝粒染色体和6对较短的、臂比大于2的近中或近端着丝粒染色体构成，这是较为进化的核型，其中红杉组Sect．Multiserales则似有比落叶松组Sect．Larix更进化的趋势。根据松科各属核型的比较，作者发现落叶松属和黄杉属非常近缘而与其他属较为疏远，因此由它们组成落叶松亚科可能较为合适，这是一个较进化的亚科。该结沦也得到形态学、解剖学、孢粉学、生物化学及古植物学等方面资料的支持。     

“低等”金缕梅类植物的起源和散布

本文根据植物类群的系统发育和地理分布相统一的原理,讨论了“低等”金缕梅类植物的起 源和散布。  “低等”金缕梅类植物(Endress1989a的概念)包括下列7科：昆栏树科、水青树科、连香 树科、折扇叶科、领春木科、悬铃木科和金缕梅科。  该类群共有13种分布区类型,东亚区的南部和 印度支那区的北部是它的现代分布中心;根据化石证据及原始类群和外类群的分布分析,以上地区最 有可能是这类植物的起源地。  “低等”金缕梅类植物起源的时间至少可追溯到早白垩纪巴列姆期,较可 靠的化石证据说明悬铃木类植物在早白垩纪阿尔必晚期出现,而昆栏树科、水青树科、连香树科和金 缕梅科植物的出现均不晚于晚白垩纪。  最后,从环境变迁和生物演化两个方面探讨了“低等”金缕梅类植物现代分布格局的形成原因。     

晚古生代的科达科——起源和演化的研究

科达科Cordaitaceae植物广泛分布于晚古生代的欧美植物区和华夏植物区，目前包括3个自然属：Mesoxylon、Pennsylvanioxylon和Shanxioxylon。根据目前资料，欧美植物区只见有前两个属，而在华夏植物区这3个属则都有分布。本文详细讨论了这3个属的茎的初生构造、雄性球果穗及胚珠，认为在这3个属中Mesoxylon最原始，Pennsylvanioxylon较进化，Shanxioxylon的茎的初生构造虽具一定的原始性(如具中始式叶迹)，但其生殖器官却相当进化。因此，本文提出Shanxioxylon是一种可塑性较强的科达植物，能够适应环境的变化，最终有可能演化为新的植物类群，如某种早期的松杉类；Pennsylvanioxylon则是一种较为特化的植物，其结局是走向绝灭。结合地层中科达科化石的分布情况，本文认为最早出现的科达植物应是Mesoxylon，它可能是由某种前裸子植物演化而来，再由其演化至Shanxioxylon和Pennsylvanioxylon。由于气候和地理环境的不同，华夏植物区和欧美植物区的科达植物各自沿着不同的路线进行演化。其中，欧美植物区科达科的演化路线可能为：某种前裸子植物→Mesoxylon的较原始类型(如M．multirame，Mitrospermum bulbosum)→Mesoxylon的较进化的类型(如M．thompsonii)→Pennsylvanioxylon的较原始类型(如P．iowense)→Pennsylvanioxylon的较进化类型(如P．nauertianum，P．birame)→绝灭。华夏植物区科达植物的可能的演化路线则为：某种前裸子植物→Mesoxylon→Shanxioxylon→Pennsylvanioxylon→绝灭，或某种前裸子植物→Mesoxylon→Shanxioxylon→绝灭或演化为某种新的植物，如某种早期的松杉类。