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半蒴苣苔属的研究(续) 总被引：1，自引：0，他引：1
李振宇 《中国科学院研究生院学报》1987,25(3):220-230
The genus Hemiboea is a curious genus of the tribe Didymocarpeae (Cyrtandroi-
deae), characterized by its peculiar pistil with one fertile carpel and its follicle-like capsule. This genus has not yet been thoroughly studied since its establishment by C. B. Clarke in 1888. In
the present paper, the taxonomic history is briefly reviewed; the external morphology, leaf his-
tology, pollen morphology and geographical distribution are discussed; a key to the 21 species
recognized by the author is provided; and the economic uses reported in various publications
are summarized.
I. Morphology
(1) Sclereids The foliar sclereids, occurring in this genus and defined by their forms,
fall into two types.
(A) Vermiform selereids This type of sclereids is noted in 15 species and may be clas-
sified into two groups according to their positions in leaf tissues. Those of the first group
are interspersed in the ground tissue around the vascular bundles of leaves and noted in 12
species, i.e.H. longisepala, H. cavaleriei, H. bicornuta, H. fangii, H. omeiensis, H. gracilis,
H. glandulosa, H. mollifolia, H. pingbianensis, H. parviflora, H. strigosa and H. gamosepala,
and those of the second group are dispersed in the mesophyll, occurring in H. subcapitata, H.
henryi and H. latisepala.
(B) Astrosclereids The sclereids of this type are discovered for the first time in Hemiboea,
dispersed in the mesophyll of a single species, i.e.H. lungzhouensis.
No foliar sclereids are found in the remaining 5 species, i.e.H. integra, H. flaccida, H.
longgangensis, H. subacaulis and H. follicularis.
The differences in forms and positions of the foliar sclereids and their absence or pre-
sence are of great help in understanding the relationship between the infrageneric taxa.
(2) Pollen grains The pollen grains of 19 species were examined with LM and SEM.
They are 3-colporate, subglobose or prolate, 20-38.8×22-28μm. The exine is 1.3-2μm
thick and the sculpture is foveolate (e.g.H. cavaleriei) to reticulate (e.g.H. omeiensis). In
Sect. Subcapitatae the pollen grains are subglobose or prolate, while those of Sect. Hemiboea are
prolate.
No pollen grains are observed in anthers of 13 speciemens of H. subacaulis var. subacaulis
and var. jiangxiensis.
(3) Seed-coat Under SEM the seed-coat exhibits considerable diversity in the genus, fur-
nishing useful characters for explaining the relationship between the two sections.
2. Geographical distribution The genus Hemiboea ranges from the eastern border of the
Xizang Plateau and Yunnan Plateau eastwards to Ryu Kyu Islands, and from the southern
slope of the Qinling Range southwards to northern Vietnam. The karst region of S. E. Yun-
nan and W. Guangxi is the centre of maximum variation of the genus and is probably its origin
centre, where the most primitive taxon exists, and where more species (13 species, i.e. 61.9 per
cent of the sum total) and more endemic species (8 species) are found than elsewhere.
3. Classification The genus consists of 21 species and 6 varieties which are classified into
2 sections. The Clarke's classification is accepted, but emended here as follows:
Sect. 1. Subcapitatae Clarke Sepals free or posterior ones connate. Muri of the seed-coat
laevigate or rugose; bottom of meshes flat, smooth or with few verrucae. Pollen grains subglo-
bose or prolate.
Sect. 2. Hemiboea Sepals connate. Muri of the seed-coat tuberculate or aliform-tuberculate;
bottom of meshes flat or concave, with dense verrucae. Pollen grains prolate.
Based on the analysis of external and internal morphological characters, the main evolu-
tionary trends in the genus are discussed and enumerated, and a hypothesis indicating the re-
lationships between the two sections is given. 相似文献
3.
陈心启 《中国科学院研究生院学报》1981,19(3):323-329
Acanthochlamydoideae, a new subfamily of Amaryllidaceae, is proposed in the pre-
sent paper, based upon the monotypic genus Acanthochlamys which was detected by
the writer in 1979 and named Didymocolpus as a new genus but was preceded by P. C.
Kao in 1980 under the former name. The genus is indeed of great morphological in-
terest. It has semicylindric leaves with a deep furrow on the ventral and dorsal sides
respectively. The lower part of the leaf is connate with, or adnate to, the lower mid-
rib of a rather large and membranous vagina . Such a feature, as far as we know, is
very rare in the monocotyledons.
The flower resembles that of Amaryllidaceae in having inferior ovary, six stamens
and corolla-like perianth with a rather long tube. But it is quite different in other
characters, such as head-like cyme, leaf-like bracts and bisulcate leaves, which all are
foreign to any taxon known in the Amaryllidaceae. On the other hand, it bears some
resemblance particularly in habit and inflorescence to Campynemanthe of the Hy-
poxidaceae, and also to Borya and Bartlingia of the Liliaceae (in the tribe John-
sonieae), but differs in its long perianth-tube and curious leaf structure. It is highly
probable that the resemblance between them is only superficial and not indicative of
direct or close relationship.
This is no doubt a very curious plant of which we still know incompletely, and
for which an appropriate place in the monocotyledons has not yet been found. Con-
sidering its floral characters, however, it seems safe for the present to place it as a
separate subfamily in the Amaryllidaceae and is juxtaposed with the Ixiolirioideae
and Amaryllidoideae, the only two subfamilies of Amaryllidaceae according to H. Mel-
chior (1964), and, of course, to either of them it is not directly related. Its true affinity
remains problematic.
The only species, Acanthochlamys bracteata, is found in Mar-er-kan (102°12'N,
31°47'E), Qian-ning (101°30'N, 30°33'E), Xiang-cheng (99°39'N, 28°54'E) and Dau
cheng (100°10'N, 29°03'E) in western Sichuan of southwest China, in open bushland
or grassland at an altitude between 2700—3500 meters. Its geographical distribution is
mapped and its morphological details are illustrated to facilitate its identification.
相似文献
4.
吉占和 《中国科学院研究生院学报》1982,20(4):439-444
The present paper is an attempt to make a taxonomic study of the little known
orchid genus Holcoglossum, as well as a comparison of the genus with its allies, such
as Vanda, Papilionanthe, Ascolabium, Ascocentrum, Aěrides, Neofinetia and Saccola-
bium.
Holcoglossum was established by Schlechter in 1919 (Orchideologiae Sino-Japoni-
cae Prodromus) as a monotypic genus, based upon Saccolabium quasipinifolium Hayata.
Five years later he published another true Holcoglossum as Aěrides flavescens, which
was referred by Tang et Wang to Saccolabium in 1951. Further investigation of this
genus was by Garay in 1972 who added two species, H. kimballiana and V. rupestris
(synonymy of Aěrides flavescens), but considered Neofinetia, a quite different taxon,
to be congeneric. It is shown that the demarcation of Holcoglossum remains cofused.
During the course of our study, the species of Holcoglossum and its allied genera are
carefully examined, we come to the conclusion that Ho lcoglossum is a distinct genus.
It is characterized by the short stem; fleshy terete or subterete, sulcate above leaves,
with their apex acute and non-lobed; thickening or keeled costa on the back of sepals,
3-lobed lip, with erect sidelobes, paralled to the column; slender and recurved spur;
footless column usually with prominent wings; 2 notched pollinia attached to linear
stipe which is tapered toward the base. In addition to Ascolabium, it differs from
Vanda, Papilionanthe, Ascocentrum, Aěrides, Neofinetia and Saccolabium by its terete
or subterete leaves on their ventral side with a furrow, from Papilionanthe by lacking
footless column, from Ascolabium by sepals and spur characters, from Ascocentrum by
slender and recurred spur, from Aěrides by the absence of a column-foot and the
appearance of spur, from Neofinetia by stipe tapered toward the base, from Saccolabi-um by both aspects of the vegetative organs and the flowers. 相似文献
5.
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. 相似文献
6.
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
李恒 《中国科学院研究生院学报》1981,19(1):29-42
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
7.
张若蕙 《中国科学院研究生院学报》1984,22(2):110-118
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
8.
木兰科分类系统的初步研究 总被引：10，自引：0，他引：10
刘玉壶 《中国科学院研究生院学报》1984,22(2):89-109
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
9.
张志耘 《中国科学院研究生院学报》1988,26(5):394-403
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
10.
The reproductive feature of the nemalionalean genus Liagora is characterized by
the laterally situated carpogonial branch which is produced by the ordinarily assi-
milative filament. A study of L. farinosa Lamx. has revealed that the carpogonial
branches of this species are not borne on the ordinarily assimilative filaments but
restricted to a kind of short filaments (referring to as “fertile filaments” in the
present article) which are, in turn, initiated by the basal cells of the assimilative
filaments. The carpogonial branches are modified furcations of the fertile filaments.
The fertile filaments may, however, grow and send out assimilative filaments concur-
rently with the maturation of the carpogonial branches. Therefore, the origin of the
carpogonial branches is best shown in their younger developing stages but more or
less obscure in age.
Boergesen, who examined Lamouroux's type, made a detailed study of L. farinosa
from the Canary Islands. The depictions given by Boergesen, Yamada (1938, f. 15),
Tseng (1941, f. 6) and Umezaki (1961, f. lA) concisely illustrated the feature of the
fertile filaments in this species, although all these workers had not envisaged the
taxonomical significance of the peculiar position of the female organs. In our opin-
ion, the differentiation of cortical filaments into assimilative and reproductive as seen
in L. farinosa (even though in a preliminary stage) suggests that the progressive
evolutionary changes have occurred in this species. The unique situation of L. fari-
nosa is, in fact, no parallel in any genus of the, family where female organs are
directly produced (or transformed) by the assimilative filaments.
It thus appears there is no justification for retaining L. farinosa in the genus
Liagora. A new genus, Ganonema Fan et Wang gen. nov. is therefore proposedfor accommodating the species, G. farinosa (Lamx.) Fan et Wang comb. nov. 相似文献
11.
木材构造特征在裸子植物系统学中的意义 总被引：1，自引：0，他引：1
本文根据木材构造特征的进化趋势对裸子植物，特别是松杉纲内各目、科的系统位置和等级
进行了探讨。笔者认为：1．南洋杉科可从松杉目中独立出来成立南洋杉目。2．银杏更近于松杉目而与苏铁科有明显区别。3．罗汉松科、三尖杉科和红豆杉科应置于南洋杉科之后，松科之前，三尖杉科与红豆杉科亲缘关系更接近。4．建立金松科是合理的。5．为侧柏从崖柏属中分出成立侧柏属补充了木材方面的证据。6．进一步探讨了松科中一些属的系统位置，并建议松属可区分为三个亚属。7．穗花杉属置于红豆杉科中更为合适。 8. 同意郑万钧在铁杉属内建立长苞铁杉组。合并黄山松和台湾松。 相似文献
12.
台湾杉属Taiwania包括秃杉T．flousiana Gaussen和台湾杉T.cryptomerioides Hayata 两种。秃杉现已列为我国一级国家重点保护植物。本文作者在光学显微镜和扫描电镜下，系统 观察了秃杉营养苗端，叶角质层内、外表面及叶子内部结构，幼茎，茎的次生韧皮部和次生木质 部的结构等。通过对秃杉各营养器官形态结构的观察，并结合有关文献资料，同杉科其它各属作了比较分析，我们不赞同将台湾杉属提升为一个单型科——台湾杉科的主张，而支持Hayata (1906；1907)早期提出的关于台湾杉属应作为杉科中的一个属，其系统位置可介于密叶杉属与杉木属之间的观点。 相似文献
13.
本文用201种禾本科植物幼苗的60个形态和解剖性状进行了聚类分析，将禾本科植物分为四个大类(一级聚合单位)—狐茅类(Festucoid)、黍类(Panicoid)，竹类(Bambusoid)和画眉草类(Eragrostidoid)。这四类基本上与分类系统中的亚科相吻合，只是芦竹亚科植物的幼苗分散聚到了其它类中。推测芦竹亚科是一个比较原始的类群，狐茅亚科、黍亚科和画眉草亚科可能是在芦竹亚科的基础上进化而来的。 除个别种外，大多数同属的种在较低的聚合水平上聚在一起，超族在亚聚合单位中基本上能够反映出来。 研究证明禾本科植物的幼苗性状在禾本科植物分类中具有重要的分类学意义。 相似文献
14.
李承森 《中国科学院研究生院学报》1982,20(3):331-342
A new psilophytic plant, Hsüa robusta, is found in the Xujiachong Formation
(Emsian) of the Lower Devonian from the Qüjing (= Kütsing) district of Yunnan,
China. This plant is tentatively referred to the Cooksoniaceae of Rhyniales.
Hsüa gen. nov.
Type species: Hsüa robusta (Li et Cai) C. S. Li.
Diagnosis: Plants erect and then creeping. Main axes dividing pseudomonopodial-
ly and bearing dichotomous lateral branches which somewhat differentiate into vegeta,
tire and fertile ones, with dichotomous root-like and rhizophore-like appendages. Spo-
rangia terminal, round to reniform or wide reniform, dehiscing along distal margin into
two equal halves. Spores homosporous, trilete. Stomata anomocytic. Protostele cen-
trarch.
Hsüia robusta (Li et Cai) C. S. Li, comb. nov.
Cooksonia zhanyiensis Li et Cai, Acta Geologica Sinica, 52 (1) 1978, p. 10, pl. II,
fig. 6.——Taeniocrada robusta Li et Cai,ib. p. 10, pl. II, fig. 7—14.
Diagnosis: Characters same as in generic diagnosis. Main axes 6—10 mm wide and
at least 24 cm long, with vascular strands 1.2—2.4 mm acr oss. Fertile branches 3—4
times equally or unequally dichotomous, 10—1.5 mm in width and up to 11 cm in length,
possessing a vascular bundle of 0.5 mm in its greatest diameter. Branches circinately
coiled in apical regions. Axial tubercles, root-like and rhizophore— like appendages aris-
ing from the main axes usually anterior to the lateral branches. Axial tubercle round
with a diameter of 2.2—2.4 mm, having a vascular bundle about l mm across. Root-
like branches 3 times bifurcate, 1—0.3 mm wide and up to 1.5 cm long, with a vascular
bundle about 0.1 mm across. Rhizophore-like appendages forked, 3—1.7 mm in width,
possessing a vascular bundle of 0.7 mm in its greatest diameter. Root-like protuberances
sometimes arising from rhilzophore-like branches. Epidermal cells of axes generally
elongate, measuring 60—290μby 25—60 μ. Stomata mainly fusiform, 90—110 μ long
and 50—60μ wide, consisting of a pair of guard cells enclosing a pore 6—15μ in length
and 1—3μ in width. Cuticle of guard cells quite thick. Stomatal density about 5 per
mm2. Sporangia 0.8—4.2 mm high, 1.0—8.2 mm across, usually having a dehiscent distal
border which measures 50—100μ broad. Demarcation between sporangium and its stalk
quite clear. Epidermal cells of basal part of sporangial walls elongate, about 100 μ long
and 30μ wide, but those of distal part isodiametrally polygonal, about 50μ in diame-
ter. Stomata, radially arranged scattering over sporangial walls, generally round about
50μ in diameter and 50 per sporangium. Spores round, 18—36μ (average 27μ) indiameter, and smooth. Tracheids of protoxylem about 10μ across; those of metaxylem
about 30μ across, with scalariform thickening.
This plant is similar to Renalia hueberi Gensel in general morphology, but differs
from the latter in possessing root-like and rhizophore-like branches.
The generic name is derived from Prof. Hsü Jen. This paper is a thesis for M. Sc. 相似文献
15.
肖培根 《中国科学院研究生院学报》1980,18(2):142-153
As a genus Acronema was first proposed by Falconer, but it was only a nomen
nudum. The genus was effectively established by Edgeworth (1851) on the basis of
a himalayan species, Acronema tenerum (Wall) Edgew. (= Sison tenerum Wall. 1828).
Bentham & Hooker had placed the genus within Pimpinella in 1867. C. B. Clarke
followed the same treatment in the Flora of British India in 1879. The much detailed
systematic work of the genus was done by H. Wolff in Engl. Pflanzenreich (1927).
The chief distinguishing character of the genus lies in the acuminulate of filamen-
tous apices of the petals.
At present the genus contains about 23 species chiefly in the himalayan regions
and South-west China, many being found in Sichuan, Yunnan and eastern Xizang.
They are usually growing under the shade of forest, roadside and riverside at the
altitude 2100—4800 meters.
In this paper 18 species and 2 varieties are presented, of which 5 species, 2
varieties and 1 combinations are considered as new and three arc first recorded fromChina. 相似文献
16.
综合研究凤头黍属与其邻近属的叶片表皮微形态、颖片及内、外稃等特征后，发表禾本科一新属——刺毛头黍属。 相似文献
17.
王文采 《中国科学院研究生院学报》1980,18(3):266-282
1. Having analyzed the external morphology of the genus Microula, the author
has proposed a series of criteria as bases for the construction of a classification scheme
of this genus. The most important ones are as follows:
1) The normally developed stem is primitive, and the strongly abbreviated stem
more advanced.
2) The small inconspicuous bracts are more primitive than the large suborbicular
densely arranged ones, which almost entirely cover the flowers and the fruits.
3) Nutlets with small dorsal pit are more primitive than those with larger pit
on one hand or those without it on the other.
4) The dorsal pit with simple margin precedes that with double margins.
5) Nutlets with subbasal areola precede those with lateral or apical areola.
6) Nutlets without glochids precede those with glochids.
2. Basing upon these criteria the genus Microula may be divided into six sections.
The section Schistocaryum may be the primitive one, and the others may be evolved
from it respectively. The possible affinities between them are demonstrated in figure
no. two.
3. The genus Microula, containing 30 species, is mainly distributed in the
Chinghai-Tibetan plateau and the majority of its species concentrates in the eastern
border of the plateau, and of the 30 species 26—that is 90 percent—are endemic
to China, and the remaining 4 are distributed elsewhere in China, too, and extending
southward and westward to Bhutan, Sikkim, Nepal and Kashmir respectively. In the
region between Heishui, Province Szechuan, and Chinghai Lake there are 9 species,
which, curiously, represent all the six sections of Microula, hence this region seems to
be the center of maximum variation of this genus. M. ovalifolia whose nutlets have
small dorsal pit and subbasal areola may be considered the most primitive species.
Thus the author is of the opinion that the western part of province Szechuan, to
which M. ovalifolia is endemic, may probably be the center of origin of the genusMicroula. 相似文献
18.
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