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1.
Begonia pellionioides YM. Shui & WH. Chen, a new species of the genus Begonia L. (sect. Petermannia (Klotzsch) A. DC., Begoniaceae), is described and illustrated. The new species is endemic to limestone areas in Southeastern Yunnan Province, China, and is most similar to Begonia hainanensis Chun & F. Chun but distinguished by its more elongated leaves with cuneate base and acuminate to caudate apex, tepals adaxially with spiny hairs and sharply triangular capsule wings with truncate superior margin. Besides, the unknown flower morphology of previously published Begonia sublongipes YM. Shui in Begonia sect. Petermannia is described.  相似文献   

2.
Conran, J. G. 1988. Embryology and possible relationships of Petermannia cirrosa (Petermanniaceae). - Nord. J. Bot. 8: 13–17. Copenhagen. ISSN 0107–055X.
Micro- and megasporogenesis in Petermannia cirrosa is reported and the relationships of the Petermanniaceae are discussed. Microsporogenesis is successive; the endothecium is spirally thickened and the tapetum binucleate and amoeboid. The ovules are anatropous and crassinucellate. A primary parietal cell is formed and divides. Megasporogenesis is of the Polygonum type. On the basis of these and other characters, the Petermanniaceae show affinities with the remainder of the Dioscoreales, and also with the Geitonoplesiaceae (Asparagales) but remain somewhat isolated.  相似文献   

3.
中国秋海棠属等翅组植物订正   总被引:1,自引:0,他引:1  
根据海南秋海棠 (BegoniahainanensisChunetF .Chun)、多花秋海棠 (B sinofloribundaL .J.Dorr)及一新种———长柄秋海棠 (B sublongipesY .M .Shui)的特征比较 ,订正了中国秋海棠属等翅组 [Sect Petermannia (Klotzsch)A .DC .],使该组在中国增至 3个种。  相似文献   

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5.
于鹏辉  伍修宇  曹述铁  易传安 《生物磁学》2011,(12):2365-2366,2323
断层解剖学作为解剖学与医学影像学等学科相结合的交叉学科,对现代化的影像技术及临床应用具有非常重要的意义。要学好断层解剖学:必须明确断层解剖学的重要性;培养学习的兴趣,注意临床针对性;抓好学习的重点,注意学习方法;打好局部解剖学知识的基础,始终贯彻断层标本与影像相结合的原则;并高度重视现代化多媒体资料的应用。  相似文献   

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8.
A partial face and mandible from the early Miocene site of Napak IX in Uganda are described here as a new genus and species of catarrhine primate, Lomorupithecus harrisoni gen. et sp. nov. The face is among the most complete specimens known for a Miocene small-bodied catarrhine. Several aspects of its anatomy indicate that the new species is a stem catarrhine, and as such, it may provide valuable information pertaining to the primitive catarrhine cranial morphotype. Lomorupithecus is most similar in its facial anatomy to members of the Pliopithecoidea, and these similarities could be interpreted in three ways. They could be symplesiomorphies, which would support the traditional view of the primitive catarrhine cranial morphotype; they could be synapomorphies reflecting a phylogenetic position of Lomorupithecus within Pliopithecoidea; or they could represent convergence. Phylogenetic analysis of Lomorupithecus along with 35 other primates indicates that it is a pliopithecoid. As such, it would be the oldest and only Afro-Arabian member of this otherwise Eurasian clade.  相似文献   

9.
Two new species of Begonia (Begoniaceae), B. baik and B. padawanensis, from Sarawak are described and illustrated. Begonia baik, a member of sect. Petermannia, resembles B. conipila, but is distinguishable by having glabrous ovary (vs sparsely hispid) and margins of bracts dentate and glandular hairy (vs entire). Begonia padawanensis (sect. Reichenheimia) is similar to B. andersonii, differing in the leaves being obtriangular‐spatulate (vs orbicular) and having 5 pistillate flower tepals (vs 4). Both new species were discovered in a sandstone area in Padawan, Sarawak.  相似文献   

10.
J C M Ahern  F H Smith 《HOMO》2004,55(1-2):1-19
This study documents and examines selected implications of the adolescent supraorbital anatomy of the Le Moustier 1 Neandertal. Le Moustier's supraorbital morphology conforms to that expected of an adolescent Neandertal but indicates that significant development of the adult Neandertal torus occurs late in ontogeny. As the best preserved adolescent from the Late Pleistocene, Le Moustier 1's anatomy is used to help distinguish adolescent from adult anatomy in two cases of fragmentary supraorbital fossils, the Vindija late Neandertals and KRM 16425 from Klasies River Mouth (South Africa). It has been suggested that the modern-like aspects of the Vindija and Klasies supraorbital fossils are a function of developmental age rather than evolution. Although Le Moustier 1's anatomy does indicate that two of the Vindija fossils are adolescent; these two fossils have already been excluded from studies that demonstrate transitional aspects of the Vindija adult supraorbitals. Results of an analysis of KRM 16425 in light of Le Moustier 1 are more ambiguous. KRM 16425 is clearly not a Neandertal, but its morphology suggests that it may be an adolescent form of such late archaic Africans like Florisbad or Ngaloba. Both the Vindija and Klasies River Mouth cases highlight the need to be wary of confusing adolescent anatomy with modernity.  相似文献   

11.
Evolutionary aspects of the arthropod heart   总被引:1,自引:0,他引:1  
Evolution has led to changes in the gross anatomy of the arthropod hearts. Changes are also seen in the ultrastructural organization of the cardiomyofiber. Thus the myofilament organization and the membrane systems (T-system and SR) vary within both Chelicerata, Crustacea and Uniramia. Yet, the variation is not haphazard, but constitutes a pattern which cannot be deduced from the gross anatomy. In the three taxa the evolutionary tendency seems to be towards a more strict sarcomeral organization of the myofilaments. This is due to parallelism. The organization of the membrane systems and the spatial relation of the interior couplings are not identical for all arthropods. However, no variations has so far been detected within one and the same order, despite differences in adaptation and size. These systems are conservative and it is suggested that they could be useful in studies of arthropod phylogeny.  相似文献   

12.
The Graveldiver, Scytalina cerdale, is a small, poorly known burrowing fish from the intertidal and subtidal zones of the west coast of North America, ranging from south‐central California to Alaska. This is the sole member of the family Scytalinidae, which is included in the Zoarcoidei. Although it was described over 120 years ago, it is rare in natural history collections and its anatomy is only imperfectly known. This article describes and illustrates the skeletal anatomy of S. cerdale based on newly prepared cleared and stained specimens. Many points of its anatomy are clarified or corrected (e.g., presence of the intercalars and ribs, in contrast to their reported absence) or described for the first time (e.g., structure of its gill‐arches). Previous hypotheses of its systematic placement within the Zoarcoidei are discussed. On the basis of preliminary comparisons, S. cerdale may have phylogenetic affinity with at least some members of the family Stichaeidae (e.g., Xiphister). However, further study is needed on the anatomy and inter‐relationships of the families of the Zoarcoidei before any conclusions can be made. J. Morphol., 2009. © 2009 Wiley‐Liss, Inc.  相似文献   

13.
Three-dimensional fetal echocardiography   总被引:4,自引:0,他引:4  
The complex anatomy and dynamics of the heart make it a challenging organ to image. The fetal heart is particularly difficult because it is located deep within the mother's abdomen and direct access to electrocardiographic information is difficult. Thus more complex imaging and analysis methods are necessary to obtain information regarding fetal cardiac anatomy and function. This information can be used for medical diagnosis, model development and theoretical validation. The objective of this article is to provide scientists and engineers with an overview of three-dimensional fetal echocardiography.  相似文献   

14.
For studying anatomy of the alive human heart, a new method of ultrasonic echography has been used. With its assistance it is possible to see all the cardiac chambers, interventricular and interatrial septa, tricuspidal and mitral valves, their chordae, papillary muscles, myocardium and pericardium. Not only their statics, but also their dynamics are investigated, when the heart contracts and its valves make movements. Owing to this, possibilities for studying cardiac anatomy in the alive people.  相似文献   

15.
Rodents are well known for the production of physically quite different audible and ultrasonic cries. Both of these cries are known to be produced in the larynx, but the anatomy of the larynx is practically unknown, it thus being difficult to analyse how the cries are produced. The anatomy of the larynx of Mus musculus is described in detail and is found to be essentially typical of that of other mammals that can fix the thorax and make independent use of the forelimbs. Unlike the larynx of microchiropteran bats, no modifications for ultrasound production are apparent, although the laryngeäl structure is ideal for the production of audible cries. However, the audible and ultrasonic cries differ so markedly that they are unlikely to be produced by the same mechanism. The lack of laryngeal specialization therefore makes the ultrasound production mechanism largely an enigma.  相似文献   

16.
The general anatomy and the detailed vascular anatomy of the latissimus dorsi myocutaneous flap is described, and its use as a free flap is illustrated. The speed and ease with which it can be raised, its long vascular pedicle, the large diameter of the donor vessels, and the potentially large size of the flap are emphasized.  相似文献   

17.
The leaf anatomy of species representing all seven genera of the Penaeaceae was studied by light and scanning electron microscopy. Due to variability and inconsistency, leaf anatomical characters are not regarded as particularly useful for systematics within or among genera in this family. Across the family, a number of taxa exhibit a trend towards amphistomatous, isobilateral leaves, generally associated with increased leaf thickness and amount of palisade mesophyll. This trend is not apparent in closely related families, e.g. Alzateaceae, Cryp-teroniaceae, Oliniaceae and Rhynchocalycaceae. Most species are found in comparatively mesic habitats and it is difficult to postulate primary xeromorphic trends in leaf anatomy. The sclerophylly encountered across the family as a whole is likely to be related to paucity of soil nutrients rather than a response to water stress.  相似文献   

18.
Zoological parks offer varied benefits and opportunities to comparative vertebrate anatomy (CVA) as it is taught at the college/university level. First, exotic species enrich and clarify the major principles of anatomy—form and function, adaptive behavior, and evolutionary process—in ways that traditional laboratory species (dogfish, frog, cat) cannot achieve. Second, students aged 18–22 are sophisticated enough to integrate gross anatomy with the functions of behavior, behavior with exhibit design, design with animal management, and management with the politics of conservation. Third, direct contacts between students and zoo person-nel (keepers, clinical and research staff) suggest career options beyond the pre-med/prevet orientations of most biology concentrators. © 1995 Wiley-Liss, Inc.  相似文献   

19.
Brian  Morton 《Journal of Zoology》1984,202(3):299-325
Sinonovacula constricta is representative of two genera of deep burrowing bivalves hitherto placed in the Novaculininae of the Tellinacea. This species, widely cultured in China, has not previously been critically examined. Aspects of its anatomy show that it should more properly be placed in the Solenacea. The presently accepted classification of this superfamily suggests that it should be placed close to Pharella in the Cultellidae but it is clear that the group requires more detailed re-examination.
Sinonovacula is somewhat posteriorly elongate with long separate siphons. The anterior pedal gape acts as a valve to the piston-like foot enabling rapid reburrowing to occur. Sensory tentacles around the pedal gape respond to mechanical disturbance and water can be squirted from the gape to, presumably, flush away the source of irritation. Modifications of this kind are rare in the Bivalvia.
The anatomy of Sinonovacula is described and related to its life style as a suspension feeder in soft intertidal muds. The ciliary currents of the mantle cavity are powerful, the labial palps in particular being large as compared with the relatively small ctenidia. The stomach is adapted for dealing with large amounts of food, though the sorting areas are not extensive; principal sorting is clearly the function of the labial palps. The style sac and mid-gut are separate (unlike the conjoined style sac and mid gut of the Tellinacea), and ensure separation of the style from the sediment loaded mid gut.
In many ways Sinonovacula foreshadows the highly modified true razor shells and conditions in these bivalves can be accounted for by further posterior elongation of a bivalve essentially similar to Sinonovacula.  相似文献   

20.
Seed structure and the taxonomy of the Cruciferae   总被引:5,自引:0,他引:5  
The external morphology and anatomy of the seeds of some 90 genera and some 200 species of the Cruciferae have been investigated. Emphasis has been laid on the relationships of seed structure to taxonomy. As regards seed anatomy, the testa is probably of greatest value in determining taxonomic relationships. Seed structure supports the Cruciferae as a natural taxon. In the present investigation, few genera and species show seed characters which are either exclusive or very distinct. Of the remainder, most genera are distinguishable from each other on a permutation of their macroscopic and microscopic seed characters. However it is difficult or impossible to distinguish between some genera on seed characters. The present investigation provides no support for tribal divisions within the Cruciferae.  相似文献   

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