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1.
Evidence from vegetative anatomy, reproductive morphology, and palynology does not support a relationship of Oceanopapaver with Cistaceae, Cruciferae, Flacourtiaceae, Papaveraceae, and Tiliaceae, but suggests placement of the genus in Capparaceae. The apparent occurrence of myrosin cells, among other features, effectively excludes all of the aforenoted families except Capparaceae and Cruciferae. However, multicellular non-glandular trichomes, bracteate inflorescences, sepals and petals each occasionally other than four per flower, presence of an androgynophore, numerous stamens, tricolporate and binucleate pollen, the unilocular mature ovary, the stipitate fruit, and the exotegmic seed in Oceanopapaver favour Capparaceae over Cruciferae. Floral histology and vasculature provide no clues about the relationships of Oceanopapaver. A few features are anomalous, most notably the presence of secretory canals and secretory cells in the genus versus their absence in Capparaceae and their rarity in Cruciferae, the trichomic floral nectary in the genus versus the massive, non-trichomic nectaries in these two families, and the straight embryo in the genus versus the more or less curved or folded embryo in the two families. The fleshy endosperm in Oceanopapaver has counterparts in a few Capparaceae, contrary to previous claims that endosperm is absent or scanty in this family. The report of stamen fascicle traces for Oceanopapaver is the first for Capparaceae, but these should be sought elsewhere in the family. Within Capparaceae the genus fits best in Capparoideae compared to Cleomoideae or the nine other very restrictive subfamilies variously proposed for Capparaceae. There is no justification for the monotypic segregate Oceanopapaveraceae. The phylogenetic and functional anatomy of vegetative and reproductive structures is discussed.  相似文献   

2.
结构植物学由植物解剖学发展而来,是植物学的一个重要分支学科.本文根据其近代的发展,分别就植物发育解剖学向植物发育生物学的发展、植物比较解剖学向植物系统发育生物学的发展,以及环境生态结构植物学三个主要部分简要介绍了50年来在我国的发展,并对它们的发展趋势进行了预测.  相似文献   

3.
结构植物学在中国的五十年发展   总被引:3,自引:0,他引:3  
结构植物学由植物解剖学发展而来 ,是植物学的一个重要分支学科。本文根据其近代的发展 ,分别就植物发育解剖学向植物发育生物学的发展、植物比较解剖学向植物系统发育生物学的发展 ,以及环境生态结构植物学三个主要部分简要介绍了 5 0年来在我国的发展 ,并对它们的发展趋势进行了预测  相似文献   

4.
The floral and vegetative anatomy of the small Australian genus Aphanopetalum were studied. Wood is described for the first time and is characterized by predominantly solitary pores, scalariform vessel element perforation plates with low bar numbers, imperforate tracheary elements with distinctly bordered pits, sparse axial parenchyma, and a combination of homocellular and heterocellular rayS. Starch occurs in both axial and ray parenchyma of the wood. Stems possess unilacunar, one-trace nodes and the uncommon feature of an endodermis with well-defined Casparian stripS. Leaves have anomocytic stomata, a bifacial mesophyll and semicraspedodromous venation or a combination of semicraspedodromous and brochidodromous venation. The tetramerous flowers are apetalous or have minute petals. The compound, half-inferior gynoecium consists of essentially totally united carpels. The pattern of floral vascularization resembles different Saxifragaceae sensu lalo in that the compound sepal-plane and petal-plane traces give rise to staman bundles as well as sepal, petal, and carpel wall venation in their respective planes. The ventral ovarian bundles are fused into a single ventral complex that subdivides at the top of the ovary to form ventral bundles and to supply the one ovule in each locule. Vegetative and floral features provide compelling evidence to suggest that Aphanopetalum has its nearest relatives among the Saxifragaceae sensu lato rather than Cunoniaceae. The genus is probably best treated as forming its own subfamily (or family) among the saxifragaean alliance.  相似文献   

5.
6.
高成芝  冯恒光  赖其瑞   《广西植物》1988,(4):329-334
<正> 芸香科黄皮属(Clausena)植物全球约25种,分布于东半球热带、亚热带地区;我国记载有9种,产长江以南各省区,以两广、云南种类较多;广西现知6种,民间大多作药用,黄皮和小叶黄皮在我国南部广泛栽培,果实供生食或加工,黄皮的优良品种为岭南佳果之一。目前正在挖掘其潜在的药用价值及进行化学成分和挥发油的研究。中国人民解放军181医院药理室,用大鼠进行动物实验,证明黄皮叶有降血脂作用。在研究黄皮属的分类时,某些种的形态特征很接近,叶的形状、大小变化大,在无花果的情况下更难区分,笔者试图从叶的解剖构造探讨种间的差异,为植物分类和生药鉴定提供依据,供临床用药及有关方面参考。  相似文献   

7.
Systematics within the genus Trichomanes sensu lato (Hymenophyllaceae, Filicopsida) have continued to be controversial because of the difficulty in identifying homologies and informative characters within high morphological diversity. Systematic relationships are investigated in this study by using a cladistic approach with 31 anatomical and morphological characters from 20 taxa which correspond to the sections defined by Morton. The results broadly confirm Morton's four subgenera: Trichomanes, Didymoglossum, Pachychaetum and Achomanes. The monophyly of Pachychaetum remains fragile and the section Lacostea appears to be excluded from its traditional subgenus (Achomanes). In addition, by producing two major 'ecological' clades (terrestrial and epiphytic), the analysis shows that several selected characters appear to be strongly linked with the ecology which may have a significant influence on the topology.  相似文献   

8.
The four species included in the family Cryptacanthodidae are eel‐like, burrowing fishes distributed in the cold‐temperate coastal waters of the North Pacific and the western North Atlantic. This study describes the osteology and aspects of the ontogenetic skeletal development of two species, Cryptacanthodes maculatus from the western North Atlantic and C. aleutensis from the eastern North Pacific. We discuss the relationships of Cryptacanthodidae among other zoarcoid families. The Cryptacanthodidae have been previously included in the Stichaeidae, but removed and classified as a separate family based on the skull, pectoral radial, and cephalic lateral‐line morphology. Our observations (similarities in gill arch and pectoral girdle morphology; specifically, a thin sheet‐like flange of bone from the posterior margin of the supracleithrum) suggest a close relationship to at least some of the members of the family Stichaeidae. J. Morphol. 276:185–208, 2015. © 2014 Wiley Periodicals, Inc.  相似文献   

9.
中国内江猪肾脏的解剖学研究   总被引:5,自引:1,他引:4  
根据医学异种移植研究的需要, 选取5 —6 月龄中国内江猪19 头, 处死后甲醛固定肾脏标本, 进行测量并与国人肾脏解剖学资料对比, 以了解中国内江猪肾脏解剖学特点及与国人肾脏的差别。结果表明内江猪肾脏与国人肾脏无大的解剖学差异, 并具有分支型、迷走型肾动脉出现率低的优点。认为从解剖学角度看, 中国内江猪肾脏完全符合异种移植的要求。  相似文献   

10.
Interpretations of skeletal anatomy claiming to show that Neandertals could not have had a similar supralayngeal vocal apparatus to that of humans are demonstrated to be flawed. Correction of the errors suggests that the Neandertal vocal apparatus need not have differed from that of recent humans. © 1993 Wiley-Liss, Inc.  相似文献   

11.
A comparative study of the secondary xylem (wood) anatomy of 11 species (38 specimens) occurring in cerrado s.s. and the adjacent gallery forest (both cerrado s.l. habitat) was made with the aim of identifying the anatomical characteristics of ecological value and correlating them with the environmental conditions. The anatomical features that vary, in general, between the two habitats are: growth ring distinctness (well or poorly defined); tyloses and deposits (more abundant in cerrado specimens); gelatinous fibres (more evident in cerrado specimens and in different patterns between habitats); variation in paratracheal and banded parenchyma (more abundant in cerrado); and more cells per parenchyma strand in cerrado. In general, gallery forest specimens have wider vessels, fewer vessels per square millimetre and larger intervessel pits, indicating more efficient water conduction, whereas cerrado s.s. specimens are the opposite, with low vulnerability and mesomorphy indices, demonstrating greater safety under conditions of water stress. © 2012 The Linnean Society of London, Botanical Journal of the Linnean Society, 2012, ?? , ??–??.  相似文献   

12.
13.
The diverse relationships of the main differential leaf and nodal anatomical characters of a number ot artificial Ilex hybrids and their parents are compared. The marginal sclerenchyma strands character is not transferred to hybrids when differential. The lignification of the unspecialized abaxial epidermal cells is dominantly inherited, except in one hybrid. The development of a distinctive adaxial hypodermis is usually suppressed in hybrids when one of its parents is lacking in this character. New characters are reported for hybrids of Ilex aquifolium × opaca , where the vasculation of petiole and midrib and the presence of periclinal subdivisions in the adaxial epidermis constitute features not known from either parent species.
The possible significance of the four different ways of expression of parental characters in the hybrid offspring is discussed with reference to: genetic control of anatomical characters; the identification of hybrid material; the evolution of leaf anatomical diversity in Ilex , and the systematic value of leaf anatomical characters.  相似文献   

14.
JARVIE, J. K. & BARKWORTH, M. E., 1992. Anatomical variation in some perennial Triticeae. Cross-sectional anatomy of glumes and leaf blades was examined in 22 taxa of the perennial Triticeae. The taxa included diploids and polyploids based largely on various combinations of the E, J and S genomes. The objective was to determine how much correlation exists between anatomical characteristics and genomic constitution. The data were analysed by principal co-ordinate and cluster analyses. The results showed that monogenomic species based on different genomes were readily distinguishable on glume and leaf blade features. Most heterogenomic taxa exhibited some aspects of each genome present except in the case of JE allotetraploids, which exhibited no E genome characteristics.  相似文献   

15.
Edith R. Saunders' contributions to floral anatomy are briefly considered. Fourteen of her abstracts and discussions and 49 of her lengthier works are cited. An index to 249 families of angiosperms sensu Airy Shaw (1973) keyed to Saunders' publications is given.  相似文献   

16.
Bordered pits occur in walls of living ray cells of numerous species of woody dicotyledons. The occurrence of this feature has been minimally reported because the pits are relatively small and not easily observed in face view. Bordered pits are illustrated in sectional view with light microscopy and with scanning electron microscopy in face view for dicotyledonous and gnetalean woods. Bordered pits are more numerous and often have prominent borders on tangential walls of procumbent ray cells, but also occur on radial walls; they are approximately equally abundant on tangential and horizontal walls of upright cells, suggesting parallels to cell shape in flow pathway design. Axial parenchyma typically has secondary walls thinner than those of ray cells, but bordered pits or large simple pit areas occur on some cross walls of parenchyma strands. There is no apparent correlation between the phylogenetic position of species and the presence of borders in ray cells or axial parenchyma. Bordered pits represent a compromise between maximal mechanical strength and maximal conductive capability. High rates of flow of sugar solutions may occur if starch in ray cells or axial parenchyma is mobilized for sudden osmotic enhancement of the conductive stream or for rapid development of foliage, flowers, or fruits. Measurement of the secondary wall thickness of ray cells may offer simple inferential information about the role that rays play in the mechanical strength of woods. © 2007 The Linnean Society of London, Botanical Journal of the Linnean Society , 2007, 153 , 157–168.  相似文献   

17.
Vasculature in the bicarpellate, pseudomonomerous gynoecium with two distinct styles is examined and compared in all of 15 genera of Celtidaceae and Ulmaceae (Urticales). Gynoecial vasculature is diversified in the families but consistet in a genus or a group of genera. Our observations corroborate the earlier suggestion that Ulmaceae (six genera) basically have three-bundled styles, while Celtidaceae (nine genera) always have one-bundled styles. Comparisons with other Urticales and with Eucommiaceae as an outgroup of Urticales indicate that Celtidaceae are more closely related to Moraceae in sharing one-bundled style (a synapomorphy), rather than to Ulmaceae. This supports a separation of Celtidaceae as a distinct family from Ulmaceaesensu lato. Based on the degree of fusion of major vascular bundles running in the gynoecium, we further distinguish three types of gynoecial vasculature in Ulmaceae and, likewise, three types in Celtidaceae, and discuss evolutionary trends of gynoecial vasculature as well as some generic relationships within the families.  相似文献   

18.
The structure of the braincases and associated nerves and blood-vessels is described. Typhlops combines primitive lacertilian features, notably the retention of a palatine artery, with specialisations such as the structure of the recessus scalae tympani. Leptotyphlops is more completely snake-like, but the two genera show in common a specialised intracranial course of the hyomandibular branch of the facial nerve, due to lateral closure of the juxtastapedial recess by the overgrowing crista circumfenestralis. The lateral closure of the juxtastapedial recess is considered as an adaptation to burrowing habits. The Vidian canal in scolecophidians is poorly defined, due to the lack of lateral ascending wings of the parasphenoid. This might constitute an archaic character contradicting the descent of snakes from any Recent lacertilian group.  相似文献   

19.
20.
The vascular anatomy of inflorescence axes and flowers ofClematis patens have been studied. The species shows a unique behaviour of the vascular bundles in the transition node from vegetative stem to pedicel: stelar bundles increase in number from six to eight as they ascend through the transition node so that the number of vascular bundles coincides with that of sepals. In the pedicel stele the resulting eight bundles are disposed opposite to eight sepals. respectively; each sepal receives its vascular supply from the bundle facing it. Morphological and anatomical evidence suggests that the calyx of eight sepals in this species should be interpreted as having consisted originally of four pairs of opposite organs, rather than as having been derived secondarily through chorisis of sepals from a calyx of four sepals as seen in most other species ofClematis.  相似文献   

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