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Upper Cretaceous pollen grains with a thick wall (exine) and sometimes protruding apertures, included in the Normapolles Pflug, are considered from a functional point of view. Because of the high development of compression-resistance features correlative with a high protection of the gametophyte, an entomophilic phase is supposed in the dissemination of some types, but anemophily appears to have been a developmental trend of apertural specialization for others. As these functional features are characteristic of the outer part of the wall (the sexine), the tetrahedral morphology of the inner part (the nexine) and the lack of evidence that it influenced the whole adaptive system suggest that angiospermic constraints have acted first at a pteridophytic stage.  相似文献   

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In the volume IV of the “Paléontologiefrançaise”, A. d’Orbigny deals in particular with Cretaceous rudists. Numerous type specimens of Hippuritidae, Caprinidae, Radiolitidae, Caprotinidae, Requieniidae belonging to his collection and deposited in the Muséumnationald’histoirenaturelle, Paris. Among the 78 species that he has studied, A. d’Orbigny introduced 41 as new ones. This review presents a picture of all types with a comment on the original definition, and set the statute, and the precise stratigraphical level of illustrated forms. The present work gives rise to the designation of 40 lectotypes, two syntypes and three neotypes.  相似文献   

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Many exposures assigned to the Miocene formation of “Marnes de Saubrigues” (southwestern Aquitaine Basin) have been studied. Their revised stratigraphical allocation has made it possible to recognize mainly Middle to Late Burdigalian age deposits which have been widely sampled. They have been correlated with planktonic zones N6 pars-N7 and NN3-NN4 and locally dated 17.7 Ma with Sr isotopes. It is noteworthy that this chronological interval is only known in the southern Basin. An inventory of the rather abundant microplankton is provided, including series crossed by drillings in the Gulf of Biscay. These deposits yield a large diversity of benthic foraminifera, nearly 400 taxa, which can be considered as a reference fauna for western Europe Burdigalian. From a geographic point of view, it has been possible to subdivise the exposures into groups according to their bathymetry. Let us point out the first discovery of Borelis in the Burdigalian of France and in the northeastern Atlantic Miocene as well. Very rare specimens of Cycloclypeus are also present in the Aquitaine Basin. Among smaller foraminifera, the occurrence of Rosalina aguayoi, Pavonitina styriaca, the last appearance of Falsocibicides aquitanicus and the persistance of the genus Almaena must be emphasized. Several assemblages supply diatoms, rare radiolaria and sometimes abundant sponge spicules; the presence of these organisms, seldom reported from the Aquitaine Tertiary, might be linked to upwelling-type currents. Bachmayerella (inc. sed.) is uncommon and cited for the first time in the Burdigalian. A few taxonomical remarks and short notes are given for some species of foraminifera, and palaeoecological details as well. Numerous taxa are represented and comparisons with the foraminifera faunas mainly from the Lower-Middle Miocene of Western Mediterranean and Paratethys are sketched.  相似文献   

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The discovery of the Lowermost Tithonian Hybonotum-Lithographicum Zone allows for the first time to define the Kimmeridgian-Tithonian boundary in the pelagic and transitional facies (Béni Kleb Fm) of the Tunisian Dorsale and to divide within the formation the Kimmeridgian-lower Tithonian grey and/or pseudonodular mudstone and the massive Tithonian limestones. The Hybonotum-Lithographicum Zone was not identified in the reefal facies (Ressas Fm) and the Kimmeridgian and Tithonian are not divided. The Ressas Fm starts earlier, with the Upper Oxfordian, Bimammatum Zone. The Kimmeridgian-Tithonian of the Tunisian Dorsale is compared with the corresponding beds in Algeria and Sicily.  相似文献   

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The region of Eger town at the foot of the Bükk Mountains in Northeastern Hungary has particular importance for the understanding the Middle and Upper Palaeolithic periods of the Carpathian Basin. One of the key-problems is the association of carinated tools and foliate points in the lithic assemblages of the sites. New investigations at the Egerszalók-K?vágó site give fundamental data for the animated discussion on the relation between Aurignacian and Szeletian.  相似文献   

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A microfauna composed of 11 species of ostracodes belonging to 11 genera have been recovered from the Bhanness Formation of Kimmeridgian age, in Central Lebanon. Four species are new and are described herein: Ektyphocythere dahressawanensis nov. sp., Dicrorygma (Orthorygma) libanensis nov. sp., Citrella? elongata nov. sp. and Procytherura inflata nov. sp. From a palaeobiogeographical standpoint, this fauna characterizes the North Gondwana province which differs from the South Gondwana province, particularly by the presence of the genus Schuleridea and the absence of the genus Majungaella.  相似文献   

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The flora from the Montceau-les-Mines Lagerstätte (Late Pennsylvanian, Stephanian, France) is preserved in small sideritic nodules and was studied in three locations in the (1) Saint-Louis, (2) Saint-François, and (3) Sainte-Hélène opencast mines. Qualitative and quantitative analyses of plant diversity and floristic composition in about 7000 nodules indicate substantial variations in the floral composition of these opencast mines. More than 50 taxa are recognized and belong to groups typical of the Late Carboniferous flora (lycopsids, sphenopsids, tree ferns, and pteridosperms). Arborescent sphenopsids and tree ferns were the major components at Saint-Louis, whereas the flora from Saint-François consisted mainly of pteridosperms; the one from Sainte-Hélène has a more balanced composition. Taphonomic and sedimentological data show that the flora contained in the nodules was hypoautochthonous to parautochthonous. The Montceau Basin displayed a mosaic of paleoenvironments (e.g., deltaic lacustrine, paludal to fluvial) which favored colonization by plants and animals.  相似文献   

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Changes in Fruiting Rhythm of Coprinus congregatus by Addition of Exogenous Mature Sporophores on the Surface of Cultures. Researches were performed over the regulating effect of mature sporophores on the fruiting rhythm of Coprinus congregatus Bull. ex Fr. Placing exogenous mature fruit-bodies on the vegetative mycelium before the accomplishment of the first flush gives an abundant and perfectly synchronized fructification for this flush. But the fruiting rhythm is then disturbed: compared to control cultures, less sporophores are produced in the following flushes, and, in most cases, the cultures are finally characterized by fewer flushes than the controls. The nature of the substance(s) hypothetically produced by mature sporophores, which may regulate the production of other fruit-bodies, and, correlatively, the fruiting rhythm, is as yet unknown.  相似文献   

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A detailed study of the upper Pleistocene and Holocene ostracode fauna from the Moroccan margin of the Western Mediterranean is here presented based on sediments of three cores drilled near the Straits of Gibraltar (Sea of Alboran), between 300 and 550 m of depth. Information on the quantitative and qualitative distribution of the ostracodes was obtained, for the first time, in this area. This study also allowed to identify recall the main climatic and eustatic variations as recorded in the sediments and the faunal composition and to identify the corresponding chronological limits from the last glacial maximum to the present time.  相似文献   

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Assemblages with blades are rare in the south of Europe and most of them are dated from the isotopic stages 4 and 3. The blades are, otherwise, often produced on Levallois cores with unipolar and bipolar methods. According to the sites, the blades are more or less retouched as different kinds of tools. However, there are no specific links between this blank and the tools, and never between the artefacts and the fauna remains (activities). The hypothesis of traditions or needs among time and space are asked without answer, while the blades are present in the north of Europe and the Near East in far older periods. Several sites can be considered to describe the variability of the technical behaviour and the archaeological context of the blades in south-east France, extending to north Italy. The two sites, Abri du Maras and Baume Flandin, located in the middle Rhône valley, yield evidence of a laminar debitage linked to a Levallois method and a “direct” method. The technical choices used in the two sites are accorded to the specificity of the laminar assemblages in the southern Europe.  相似文献   

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The Neolithic site of Bangu-dae (6000-1000 B.C.), south-east of the Korean peninsula, presents numerous rock carvings of cetaceans (n = 46, 19.9% of the figures), and especially large species. Among these two families of baleen whales (Balaenidae and Balaenopteridae) and the sperm whale can be identified. This site also presents whaling scenes suggesting that the Neolithic populations who lived along the coast of Korea were among the first to take advantage of coastal whales. All these carvings give exceptional evidence on the prehistoric beginning of whaling.  相似文献   

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