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25 April 1999, Volume 21 Issue 02
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  • Articles
    Study on Structure and Localization of Acid Phosphatase of Mycorrhizal Root of Cymbidium sinense (Orchidaceae)
    FAN Li, GUO Shun -Xing, XIAO Pei -Gen
    1999, 21(02):  1-3. 
    Abstract ( 3057 )   HTML ( )   PDF (534KB) ( 1219 )   Save
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    The microstructure and ultrastructure of mycorrhizal root of Cymbidum sinenese (Andr.) Wild were studied. The results showed that this species possesses the typical root structure of orchids. There is no passage cells in the exodermis of root. Mycorrhizal fungi invade into the cortex by destroying the velamen and exodermal cells, and form pelotons in cortical cells. The hyphae colonizing cortical cells were separated from the cortical cells by electron- lucent material and cortical cell plasma membrane and digested. They often gathered to form clumps. Localization of acid phosphatase revealed that this enzyme possessed higher activity in the cortical cells containing hyphae. Many products of it also occurred on cortical cell plasma membrane surrounding hyphae and degenerated hyphae cell wall. Higher acid phosphatase activity was observed in many vesicles in the cortical cells infected by fimgi. These enzyme vesicles gathered around the invaded hy-phae and often fused with each other, or with cortical cell plasma membrane surrounding hyphae to digest these hyphae. It means cortical cells were able to release hydrolytic enzyme to digest the invaded hyphae.
    Pollen Ultrstructure of Pentapylacaceae and Sladeniaceae and Their Relationships to the Family Theaceae
    WEI Zhong-Xin,LI De-Zhu,FAN Xi-Kai,ZHANG Xiang -Lan
    1999, 21(02):  1-3. 
    Abstract ( 3195 )   HTML ( )   PDF (555KB) ( 1338 )   Save
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    To elucidate taxonomic relationships among the families of Pentapylacaceae,Sladeniaceae and Theaceae,pollen grains of genera,ca.20 species representing three families stated above were examined by light,scanning electron,and transmission electron microscopes.The comparison of pollen morphology shows that the pollen grains of Sladeniaceae are very similar to those.Their pollen grains are oblate to nearly spheroidal and 3- solporate,from rugulate to rugulate -reticulate sculptures and exine structure consisting of thick tectum and columellae,and thin endexine. Howere,the pollen grains of Pentapylacaceae are different relatively from those of Theaceae for having nearly psilate pollen surface and exine structure consising of thin recum,undeveloed columellae and thick endexine though the pollen shape (oblate) and aperture (3-colporate ) are similar to those of Theaceae.As far as the pollen sculpture and exine structure are concerned ,Pentaphylacaceae is more similar to Clematoclethra Maxim. of Actinidiaceae than of Theaceae.
    The Genus Arachnocrea, A New Record to China and Their Geographical Distribution Pattern in the World
    LTU Pei-Gui, YOSHIMICHI Doi, WANG Xiang- Hua
    1999, 21(02):  1-3. 
    Abstract ( 2573 )   HTML ( )   PDF (375KB) ( 1276 )   Save
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    The taxonomic characteristics and position as well as delimitation of the genus Arachnocrea are dis-cussed. One species Arachnocrea scabrida Doi collected from Xishuangbana Dai Autonomous Prefecture, Yun-nan Province, P.R.China is compared with the specimens from Japan (holotype) and New Zealand as well as other specimens on macro - & micro - morphology and anatomy. The range of variations of this species was de-fined. It is a new record to China. In spite of the geographical distribution of all species in the genus Arach-nocrea in the world shows the modem patterns of the temperate zone in the north hemisphere. It can be stretched to the tropical area of Southeast - Asia, it is possible that the genus was originated in this area histor-ically. It is suggested that the tropical area might be a center of differentiation of species in the genus.
    A Cytogeological Study of Genus Camellia
    ZHANG Wen - Ju, MING Tien - Lu
    1999, 21(02):  1-3. 
    Abstract ( 3482 )   HTML ( )   PDF (681KB) ( 1299 )   Save
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    In this paper, the origin and evolution of genus Camellia was discussed by cytogeographical method. The results were based on the information on chromosome numbers of 62 species and on karyotypes of 54 species in 10 sections, 52 and 45 of total species respectively. There was stable basis number (x = 15) and various ploidy (from 2x to 8x) in Camellia. Every section contained diploid and some of them were all diploid. Poly-ploid species were mainly in Sect. Camellia, Seci.Paraccimellia and Sect. Theopssis, and distributed in the north-east, west and north of distribution of Camellia, presenting the tendency that polyploid was more in the north and west than in the south. Karyotypical evolution in Camellia agreed with Stebbins theory, from symmetry to asymmetry. Sect.Archecamellia contained the most symmetrical karyotype and was the most primitive group in 10 sections; Sect. Camellia was the most advanced groups. Sect. Heterogenea, including C. yiavumensis, was not the most origninal group in Camellia, because of its high asymmetrical karyotype. Camellia might be origi-nated in Indochina Peninsula, then dispersed mainly to northern area and differentiated rapidly in the present distributio center ,Yunnan ,Guangxi and Guangdong ,and formed most speciees of Camellia
    A New Species of Magnolia from Henan
    ZHAO Tian-Bang,SUN Wei-Bang,SONG Liu-Gao,CHEN Zhi-Xiu
    1999, 21(02):  1-3. 
    Abstract ( 3063 )   HTML ( )   PDF (132KB) ( 1037 )   Save
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    M.dedudata Desr.similis,sed floribus terminalibus axillarbusque,tepalis exteriorebus minoribus interdum calycoidibus facile differt.
    Discovery of 3 ~ 7 Ovules in One Carpel of Magnolia delavayi
    CONG Xun, LU Yuan- Xue, ZHANG Yan- Ping, WU Quan -An, YUE Zhong -Shu
    1999, 21(02):  1-3. 
    Abstract ( 2271 )   HTML ( )   PDF (272KB) ( 970 )   Save
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    This paper deals with the number of ovules in Magnolia delavayi. The fruits from two population of M.delavayi were checked anatomically. The result shows that the number of ovules is variable. 2 ~ 7 ovules were observed in different carpels from the same fruit of M. delavayi. 3, 4, 5, 6 and 7 ovules in one carpel were discovered in the genus Magnolia for the first time. The number of ovules in a carpel is the most important taxonomic characteristic that distinguishes two genera. Magnolia and Manglietia. There are two ovules in one carpel of the genus Magnolia while 4 ~ 16 in Manglietia. The discovery of 3 ~ 7 ovules in one carpel of Magnolia delavayi implies that Magnolia and MangHetia may be the same genus. This result supports Baillon' s proposal that the genus Manglietia should be incorporated into the genus Magnolia.
    Taxonomic Revision on Cotoneaster conspicuus (Rosaceae)
    ZHOU Li- Hua, WU Zheng- Yi
    1999, 21(02):  1-3. 
    Abstract ( 3231 )   HTML ( )   PDF (411KB) ( 1368 )   Save
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    Cotoneaster conspicuus Messel is an ornamental plant with outstanding value for decoration. Based on the species which is distributed in China to Himalayan and with comparable stable characters in the apomictic genus, names of one series (Series Conspicui Klotz), 5 species with 7 specific epithets ( C. conspicuus Messel; C. conspicuus Comber; C. conspicuus Marquand; C. conspicuus Marquand ex Klotz; C.decora hort.ex Rehd; C.nanus (Klotz) Klotz; C.permutatus Klotz; C.plurifloms (Klotz) and three names of varieties ( C. microphyllus var. conspicuus Messel; C. conspicuus var. decora Russell; C. conspicuus var. nanus Klotz) have been validly published since establishment in 1930's. This is a typical example with nominal confusion because of using over loaded detail characters in taxonomic treatment of the apomict population. On the basis of specimen observations of 33 numbers and 63 duplicates which are pre-served in PE and KUN, 7 numbers and 9 duplicates of type specimens which are loaned from BM, K & A, and observation of mang living plants cultivated while considering the cytological evidence, a taxonomic revi-sion of this species was carried out. All above names were reduced as synonyms of Cotoneaster conspicuus Messel as result.
    Two New Species of Euonymus(Celastraceae) form Guizhou
    CHEN Qian-hai
    1999, 21(02):  1-3. 
    Abstract ( 2876 )   HTML ( )   PDF (154KB) ( 1211 )   Save
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    Species habitu E.acanthocarpo Franch. affinis, a quo differt pedunculis brevioribus, 2-3 cm longis, capsulis dense furfuraceis, nonnunquam pauciaculeatis, aculeis 0.5-l nun longis. E.chuii Hand. - Mazz.similis, qui ramulis laevibus, petiolis brevissimis vel nullis, pedunculis gra-cilibus, capsulis laxe aculeatis vel sublaevibus distinguitur.Frutex scandens, radicellis adventitiis; gemmae ovoideae, 4-5 mm longae; ramuli juvenes quadrangulati, dense verrucato - lenticellati. Folia opposita,sempervirentia, crasso - chartacea,Oblonga vel elliptica, 10-13 cm longa, 3.5-5 cm lata, apice acuminata vel acuta, basi late cuneata vel breviter angustata, margine remote serrulata, nervis lateralibus 7-8 - jugis, tenuibus,utrinque nonnihil conspicuis, venulis utrinque obscuris; petioli 8-12 mm longi,verrcuclosi.Dichasia 3 - dichotoma, axillares, pedunculi qudrangulati, 2-3 cm longi; sepala 4, semiorbicu-lata; filamenta gracilia, circ. l.3 mm longa. Capsulae globosae, 6-l0 mm diam., fusco - brun-neae, apice rotundatae, dense furfuraceae, nonnunquam pauciaculeatae, aculeis 0.5-l mm longis, laxis.
    RAPD Analyses of Nageiaoids
    WANG Ting,SU Sing-Juan,HUANG Chao,ZHU Jian-Ming
    1999, 21(02):  1-3. 
    Abstract ( 2382 )   HTML ( )   PDF (233KB) ( 1103 )   Save
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    Choosing Podocarpus imocarpus imbricatus,Podocarpus nagi,Podocarpus fleuryi,Podocarpus neriifolius and Podocarpus macrophyllus are analysed through the RAPD techniques.Eighty primers from 4 operon kits were screened and 9 of them were able to produce clear polymorphic patterns.The results generated by using UPGMA algorithm to cluster genetic distances calulated from RAPD data imply: 1)the studied species are apparently clustered into three subgroups,which aupports the treatment of constructing corresponding sections,Sect.Dacrycarpus ,Sect.Nageia and Sect. Podocarpus in the genus Podocarpus,2)it is unreasonable to separate nageiaoids from Podocarpus and to establish a new family named Nageiaceae
    A Systematic Synopsis of the Genus Camellia
    Ming Tien-lu
    1999, 21(02):  1-3. 
    Abstract ( 2989 )   HTML ( )   PDF (202KB) ( 1173 )   Save
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    The genus Camellia is only distributed in the Eastern Asia and contained a lot of important eco-nomic plants. So far about 300 species have validly been published and have never been completely revised. Since 1989 the author has been closely involved with the revision of system and species of this genus. Linnaeus (1753) described 2 genera and 2 species ( Camellia japonica L. and Thea sinensis L.). Dyer (1874) reduced 2 sections under genus Camellia. After a synopsis of genus Camellia published by Cohen Stuart (1916), the number of species was raised to 38. Mechior (1925) divided Camellia into 3 genera (Piquetia, Stereocarpus and Camellia), in which genus Camellia included 5 sections (Eriandria, Calpandria, Eucamellia, Theopsis and Thea) and about 50 species. Nakai (1940) divided Camellia to 4 genera (Camellia, Camelliastrum, Thea and Theopsis) and about 59 species. J. R. Sealy (1958) reduced the above mentioned genera to genus Camellia and presented a taxonomic system of 12 sections and 82 species for the first time. After then. Prof. H. T Chang (1981 ~ 1996) published a new system of Camel-lia including 4 subgenera, 22 sections and about 300 species.
    Primary Structure and cDNA Cloning of the Antifungal Protein GAFP - I from Gastrodia elata
    HU Zhong, HUANG Qing-Zao, LIU Xiao-Zhu, YANG Jun-Bo
    1999, 21(02):  1-3. 
    Abstract ( 3059 )   HTML ( )   PDF (418KB) ( 1215 )   Save
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    The Gastrodia Antifungal Protein GAFP - I was purified from topical corm of Tian Ma ( Gastrodi-a elata), which can strongly inhibit the mycelia growth of seprophytic fungi and plays an important role in the defence mechanism of plants to restrict and prevent the infection of the fungus Armillaria mellea. This paper reports the primary structure and the cDNA nucleotide sequence of GAFP - I. The N - terminal 7 amino acid sequence to be SDRLNSG - was determined by automatic sequencer and used for synthesizing a degenerated primer. The mRNA from the Gastrodia conn was amplified to be a specific cDNA of about 600 bp through a 3' - RACE experiment with the degenerated primer.
    Cloning and Nucleotide Sequence of cDNA for the Glycerol -3- Phosphate Acyltransferase from Cucurbita ficifolia
    YANG Ming-Zhi, CHEN Shan- Na, YAN Bo, LIU Ji-Mei, HUANG Xing- Qi
    1999, 21(02):  1-3. 
    Abstract ( 2383 )   HTML ( )   PDF (256KB) ( 1102 )   Save
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    According to the cDNA sequence of GPAT from squash ( Cucurbita moschata) reported in 1988, using RT - PCR technical, we isolated the cDNA encoding a glycerol - 3 - phosphate acyltransferase ( GPAT) from figleaf gourd ( Cucurbita ficifolia) cotyledons and subcloned in pGEM - T vector system. The cDNA and the deduced amino acid sequence of figleaf gourd GPAT have 98 and 96.5 homologous with squash respectively. Among the deduced amino acid residues thirteen of them are different from that of squash.
    The constituents of Ervatamia divaricata
    YU Yang, LIU Ji -Kai
    1999, 21(02):  1-3. 
    Abstract ( 2425 )   HTML ( )   PDF (243KB) ( 1248 )   Save
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    Eight compounds have been isolated from the aerial part of Ervatamia dwaracata (L.) Burk. Their chemical structures have been identified as cycloart - 23 - ene - 3β, 25 - diol (1), 3β - hydroxycy-cloart-25-ene-24-one (2) and cycloeucalenol (3), β - sitosterol, 3β - amyrin acetate, daucos-terol, ervatamine (4), tabemeamontanine (5) on the basis of spectral evidence. Three cycloartanes, cy-cloart - 23 - ene - 3, 25-diol (1), 3-hydroxycycloart-25-ene-24-one (2) and cycloeucalenol (3), are reported for the first time from the genus Ervatamia.
    A Acetylenic Acid from Diploclisia glaucescens
    YANGYe-Kun, GAO Cheng- Wei, QIU Ming- Hua, NIE Rui-Lin
    1999, 21(02):  1-3. 
    Abstract ( 2321 )   HTML ( )   PDF (199KB) ( 1312 )   Save
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    A acetylenic acid, ocetadecanoic acid - 9 - yne has been isolated from the stem of Diploclisia glaucescens. Its structure was elucidated by spectral method and chemical reaction. In addition, triacontanoic acid, undecanoic acid and β - sitosterol were also obtained. One of them, ocetadecanoic acid - 9 - yne was isolated from D. glaucescens for the first time. It shows stronger PAI- 1 bioactivity.
    Yunnancoronarin D, A New Diterpenoid from Hedychium yunnanense
    ZOU Cheng, ZHAO Qing, HAO Xiao -Jiang, CHENG Yao- Zu, HONG Xin
    1999, 21(02):  1-3. 
    Abstract ( 2688 )   HTML ( )   PDF (145KB) ( 1283 )   Save
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    Three diterpenoids, yunnancoronarin D (1), forrestin A (2), and hedychenone (3) were iso-lated from the rhizomes of Hedychium yunnanense Gagnep. The first one is a new compound and its structure was elucidated as 13 β - furanolabda -6-oxo-7, 11- dien - 17 - ol by spectra methods.
    Structures of Rubiarbonone B and C
    ZOU Cheng, HAO Xiao-Jiang, CHEN Chang- Xiang, ZHOU Jun
    1999, 21(02):  1-3. 
    Abstract ( 2507 )   HTML ( )   PDF (146KB) ( 1336 )   Save
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    From the roots of Rubia yunnanensis, two new arborane type triterpenoids, rubiarbonone B and C were isolated and their structures were elucidated as 7β, 19α, 28 - trhydroxyarbor - 9 (11) - en - 3 - one and 28 - acetoxyl - 7β, 19α - dihydroxyarbor -9(11) - en - 3 - one respectively by spectral and chemi-cal methods.
    Biodiversity Management and Utilization in the Context of Traditional Culture of Jinuo Society in S Yunnan, China
    LONG Chun-lin, Taku ABE, WANGHong,LI Mei -Lan, YAN Heng- Mei, ZHOU Yi -Lan
    1999, 21(02):  1-3. 
    Abstract ( 3126 )   HTML ( )   PDF (653KB) ( 1469 )   Save
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    The biodiversity management and utilization in the context of traditional culture of Jinuo nationali-ty, an ethnic group who have been practicing swidden cultivation in Xishuangbanna of SW China for hundred years, are investigated and studied by employing ethnobiological approaches. Through surveying and analyz-ing folk land classification, farmers calendar, swidden cultivation, religious beliefs, non - timber forest product collection and hunting, we gathered plentiful indigenous knowledge of conservation, management and uses of biodiversity in Jinuo society, many of which are potential in modem practice of conservation and uti-lization of biodiversity. The Jinuo people have the tradition to preserve nine types of forests, fig trees and four wildlife species. They gather 23 insect species as food, which are believed to be helpful for pest control. Lo-cal people collect and use 60 ~ 70 plant species for medicinal purposes. We concluded that scientific implies on biodiversity management are involved in traditional culture. The medicinal plants and edible invertebrates collected and used by the Jinuo people are reported here for the first time.
    The Variation of Fatty Acid Composition in Ixora chinensis Seeds at Various Stages of Development and Maturation
    HUANG Min-Quan, LU Ying-Jing
    1999, 21(02):  1-3. 
    Abstract ( 2428 )   HTML ( )   PDF (252KB) ( 1183 )   Save
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    This study analysed the variation of fatty acid composition in the total lipids from Ixora chinensis seeds at various stages of development and maturation. The result supports the authors opinion that crepenyn-ic and ixoric acids might be biogenetically related while the former might be the precursor of the latter, which was proposed by the authors in the paper published previously.
    Pollination Mechanism and Mating System of Sagittaria pygmaea (Alismataceae)
    WANG Xiao-Fan, CHEN Jia - Kuan
    1999, 21(02):  1-3. 
    Abstract ( 2507 )   HTML ( )   PDF (420KB) ( 1474 )   Save
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    The pollination mechanism and mating system of Sagittaria pygmaea were studied synthetically. In natural or experimental populations, interfloral pollination by insects was observed, and the pollen flows are mediated by insect pollination. Most pollen grains moved by pollinators are very near to neighbors, occa-sionally longer distance pollination is occurred. The pollen flows mediated by wind were not found. Results of artificial isolation and pollination showed that the fruit - sets after artificial selfing/outcrossing were consider-ably high, and that the monoecy and dichogamy in inflorescence were outcrossing mechanisms. Using isozyme genetic markers, the mating system parameter of a population in this species was estimated quantita-x lively. According to the value of the outcrossing rate ( t = 49. 9% ) , the mating system of the species stud-ied could be a concurrent selfing/outcrossing system. The authors deduced that the higher rate of selfing of population in S. pygmaea should be due to the frequency of crossing between different ramets in the same in-divadual.
    Genetic Diversity and Its Relationship with Breeding System of Ranalisma rostratum
    HU Xiao-Hui, CHEN Jia -Kuan, WANG Jian -Bo, HE Guo-Qing, Ge Song
    1999, 21(02):  1-3. 
    Abstract ( 3304 )   HTML ( )   PDF (383KB) ( 1174 )   Save
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    Genetic diversity among 6 populations of Ranalisma rostratum, Sagittaria guayanensis ssp. lap-pula, Sagittarw, wuyiensis and Sagittarui pygmaea were investigated by using the assay of vertical slab poly-acrylamide gel electrophoresis. Endangered species R. rostratum with inbreeding and great proportions of vegetative reproduction maintained lower level of genetic variation than the average of plant species. Its ex-pected heterozygosity and observed herozygosity were 0.064 and 0.104 respectively. S. guayanesis with in-breeding maintained very low level of genetic diversity. Its expected heterozygosity and observed heterozygos-ity were 0.039 and 0.066 respectively. The genetic diversity of S. pygmaea with great proportions of out-breeding and vegetative reproduction was the highest among these four species.
    Embryology of a Tibetan Medicine Halenia elliptica
    XUE Chun -Ying, HE Ting- Nong, LIU Jian- Quan
    1999, 21(02):  1-3. 
    Abstract ( 2786 )   HTML ( )   PDF (509KB) ( 1571 )   Save
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    Abstract The present paper firstly reports the development of microsporangium, male gametophyte, megas-porogenesis, female gametophyte and embryogeny of Halerda elliptica, a famous Tibetan medicine. The an-ther is tetrasporangiate and its wall development conforms to the dicotyledonous type and comprises of epider-mis, endothelium, two layers of middle cells and tapetum at the mature stage. The tapetum has dual origin and is similar to the glandular type. Cytokinesis is of the simultaneous type and microspore tetrads are mainly tetrahedral. Pollen grains are mainly 3 - celled when shed. The ovary is bicarpellate. The fused margins of two carpels enlarge and intensively protrude into the ovary locule with four lines of ovules. The ovule is unitegmic, tenuinucellate and orthotropous. The development of embryo sac is of the Polygomim type. The development of endosperm conforms to the nuclear type and the embryogeny corresponds with the Physalis I variation of Solanad type. A massive hypostase tissue exists from the 2 - nucleate embryo sac to the polycel-lar proembryo stage. Three antipodal cells persist at the mature embryo stage. The embryo is at the late glob-ular stage when seeds released from the capsule. Most embryological characters are similar when compared with other taxa in Gentianinae.
    Reproductive Biology of Chloranthus henryi (Chloranthaceae) in Northeastern Yunnan
    WANG Yue-Hua, YANG Ke, MA Shao-Bin
    1999, 21(02):  1-3. 
    Abstract ( 2772 )   HTML ( )   PDF (541KB) ( 1057 )   Save
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    Abstract By investigating the reproductive biology of Chloranthus henryi in Northeastern Yunnan, the re-sult shows that the plant mainly reproduces by seeds. Vegetative reproduction occasionally occurs when the sympodial rhizome divides from two terminal buds. Both terminal and lateral inflorescence can produce ma-ture fruit and seedlings are found around the parent plants, their stamen, however, interestingly heteromor-phic. The anthers of terminal inflorescence developed under ground are bigger and each of them has 3 elon-gated connectives and 4 pollen sacs. On the other hand the anthers of lateral inflorescence developed above ground are smaller and each of them has one shortened connective with 2 pollen sacs only. The fhutset of terminal inflorescence is about 63 in average and that of lateral is 76 and 83 in average. The result of pollination insect investigation, bagged pollination experiments and indoor cultivation show that the plant is not insect - pollinating but self- pollinating, which is different from other species of Chloranthus. The het-eromorphosis of its anther might be a simplifying adaption to pollinating style.
    Pollen Morphology of Prunoideae of China(Rosaceae)
    ZHOU Li-Hua,WEI Zhong-Xin,WU Zheng-Yi
    1999, 21(02):  1-3. 
    Abstract ( 3479 )   HTML ( )   PDF (480KB) ( 1178 )   Save
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    This paper deals with a systematic study of the grains of the Prunoideae(Rosaceae) including the genera Exochorda,Princepia,Sinoplagiospermum,Amygdalus,Ameniaca,Cerasus,Padus,Laurocerasus,Pygeum and Maddenia in China. In above genera most species have tricolporate pollen grains. In Sinoplagiospermum uniflora ,however a few pollen grains are pericolporate. The shape of pollen grains varies from subspheroidal to prolate and the size varies within(20.00- 44.12)um ×(17.85- 36.95)um. Amb 3-lobed circular in commom. The colpi are usually long but narrow at two ends.