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1.
A nearly complete specimen of a heteromorphic ammonite belonging to the genus Dissimilites Sarkar, 1954 (Ammonoidea, Ancyloceratina) has been collected in the Lower Barremian from south-east France. It is the first time that a such sample has been collected since the discovery by d'Orbigny in 1842 of the first specimens belonging of this taxon. Hypothetic until today, the existence of a spire in the first development of the shell is confirmed and a new diagnosis of the genus is given. Finally, the specific content of the genus is briefly analyzed as also its stratigraphical occurrence.  相似文献   

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《Annales de Paléontologie》2017,103(4):283-292
Thirteen species of macroinvertabrates have been identified for the first time from the Turonian deposits of the Libreville region. Seven ones correspond to bivalves: Lima (Plagiostoma) subsimplex Thomas and Péron, 1890, ?Osteomya sp., Plicatula ferryi Coquand, 1862, Pfourneli Coquand, 1862, Pventilabrum var. suffetulensis Pervinquière, 1912, Plicatula sp., Pleuromya sp.; three other ones are echinoid species: Mecaster batnensis (Coquand, 1862), Mecaster nicaisei (Coquand, 1862), Mecaster sp.; and the last three are gastropods: Cylichna sp. ? Pterocerella poinsettiformis Stephenson, 1941, Columbellina sp. Excepted Plicatula ferryi Coquand and Pventilabrum var. suffetulensis Pervinquière which are identified in the Senonian of Gabon, all species are found for the first time in Gabonese coastal basin. Their paleobiogeographic distribution is extended to Gabon. In Gabonese coastal basin, the stratigraphic and geographic ranges of the Plicatula genus are extended in Turonian and Libreville region respectively. The macrofaunal assemblage found in the Libreville region is cosmopolitan. Its shows paleogeographical affinities with Tethys and south of South Atlantic.  相似文献   

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Statistical comparison between bird populations from Lower and Middle Pleistocene and present ones makes it possible to demonstrate evolutionnary shifts such as increase in size or, on the contrary, decrease in size in some lineages and to discover some species or subspecies already found in Central Europe, in layers of the same epoch. In some other lineages the observed variations seem to be regarded as possible adaptations to local geographical conditions.Moreover the study of the birds contributes richly to the reconstitution of climates and biotops. The percentage variations of «cold birds in a given site makes it possible to confirm climatic fluctuations already discovered by other methods of study.  相似文献   

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《L'Anthropologie》2018,122(2):87-110
In the present study, the chronology of several intraloessic Upper and Middle Palaeolithic sites, located in Moldova, Dobrogea and the eastern Danube Plain, is re-examined and better defined on the basis of new chronological data (IRSL ages on loess, ESR/U-Th ages on teeth) and also biostratigraphic and pedostratigraphic evidence. Middle Palaeolithic occupations have been identified in the MIS 6 loess L2 (interstadial episode), the MIS 7 pedocomplex S2 and the red soils S3 presumably assigned to MIS 9. These results are questioning the chronological extension of the Middle Palaeolithic in Romania which until early 2000 (Păunescu, 1999 a, b; Cârciumaru, 1999) was restricted to the Upper Pleistocene (short chronology: 130–35 ka; MIS 5-MIS 3). Hence, we demonstrate herein that Humans were already present during the Middle Pleistocene at the eastern periphery of the Carpathian Mountains, along the Danube valley and its tributary, the Prut River.  相似文献   

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B. Le Rû  Y. Iziquel 《BioControl》1990,35(2):173-183
Résumé Cet article présente les résultats obtenus en 1987 sur des points non encore abordés précédemment dans le cadre de l'étude des circonstances épidémiologiques favorisant le déroulement de l'Entomophthorose àNeozygites fumosa (Speare) Remaudière et Keller, pathogène de la cochenille du maniocPhenacoccus manihoti Matile-Ferrero (Hom.: Pseudococcidae). Il montre notamment que l'évolution de la maladie, très rapide, correspond à la succession de 2 phases: une première phase, d'implantation, fortement liée à la taille et à la structure des colonies et une deuxième phase (épizootique au sens strict) indépendante de leur taille et de leur structure. Son évolution appara?t plus liée à la régularité des pluies qu'à la quantité d'eau. Les conditions sont très favorables quand l'humidité relative est supérieure à 90% pendant au moins 5 heures par jour de fa?on régulière. Le r?le important joué par la durée d'humectation du feuillage est montré ici pour la première fois. La densité des conidies du pathogène dans l'air est proportionnelle aux taux de mycose observés dans les populations deP. manihoti.   相似文献   

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During the 20th century, because of urbanization, most palaeontological sites yielding plants (Hettangian–Sinemurian in age) from the city of Mende have disappeared, or they have been forgotten. This article presents a synthesis of sites yielding plants, from their discoveries in the 19th century to recent prospecting. New lithostratigraphic and palaeobotanical data are brought for two historic sites (Ravin del Pouset and Petit Séminaire), as well as two new localities (Causse d’Auge road and Gardès road). This study reveals the diversity of plant-containing lithofacies (dolomudstone, marl, limestone/calcarenite and oo-bioclastic limestone) and the diversity of plant preservations (charcoalified compressions with or without cuticle, isolated cuticle, external casts/impressions). Microfaciological study of plant beds demonstrates the diversity of depositional environments. Protected, restricted and shallow environments with low wave exposure and probable euryhaline conditions are clearly the most favourable to the accumulation and the preservation of fossil plants. These early Liassic palaeofloras, among the southernmost yet reported for Laurasia, are of significance for the plant geography and global paleoecology at that time.  相似文献   

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The origin and evolution of birds: 35 years of progress. Birds are dinosaurs – specifically, small feathered and flighted theropod dinosaurs that probably originated in Laurasia during the Late Jurassic over 140 million years ago. They are most closely related to other small theropods such as dromaeosaurs and troodontids, terrestrial predators that were fleet-footed hunters. The origin of birds is a classic example of two kinds of macroevolution: the phylogenetic origin of the group, and the sequential assembly of adaptations such as flight that are indelibly associated with birds. These adaptations were not assembled all at once. Rather, a great many characteristics associated with birds and flight first appeared in non-avian dinosaurs, where they were used for many purposes other than flight. These included insulation, brooding, and probably display and species recognition. Birds diversified steadily but gradually after their origin, which is identified with the origin of flight (Archaeopteryx); forelimb and other flight-associated features evolved more rapidly than features associated with the posterior skeleton. The first birds grew more slowly than extant birds do, and more like other small Mesozoic dinosaurs; like them, they probably matured sexually well before they completed their active skeletal growth. The origin of flight is not a problem of “trees down” or “ground up,” but rather an examination of the order in which diagnostic flight characters evolved, and what each stage can reveal about the functions and habits of bird outgroups at those evolutionary junctures.  相似文献   

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《L'Anthropologie》2021,125(5):102950
Paleolithic studies on the Japanese Archipelago started from the excavation of the Iwajuku Site in 1949. In 2000, research efforts were damaged by a forgery incident, which was concerned with the Lower/Middle Paleolithic period. After completing the investigation on the incident, the presence of the Lower/Middle Paleolithic remains unsolved. However, we have entered a new stage of research on the Upper Paleolithic for which over ten thousand sites were discovered. The new research framework places, at the heart, tephra-based lithic chronology, site structure analysis that investigates a site's formation process through conjoined pieces and parent rock analysis, and obsidian archaeology in which diachronic research is conducted on obsidian source exploitation and circulation range. Now unique characteristics of Japanese Paleolithic culture are coming to light, beginning with the migration from the neighboring continent, connecting East Asia through the Paleolithic Cultural Corridor around the Sea of Japan and the Obsidian Road, and nurturing the unique traditions of lithic production.  相似文献   

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《Comptes Rendus Palevol》2002,1(7):587-598
One of the major contributions of Alcide d’Orbigny to palaeontology is his work on the Danian of the Paris Basin. The Danian material includes well-preserved external imprints of Invertebrates. By making casting of these imprints, Alcide d’Orbigny inaugurated an original technique, which enabled him to describe more than 40 species. The question of the age of the Danian localities has long been debated since that time. It was settled once and for all in the seventies by micropalaeontologists.  相似文献   

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Résumé L'il composé «branchial» de Dasychone bombyx est constitué de plusieurs yeux élémentaires. Chacun d'eux est associé à une cellule pigmentaire qui forme un manchon autour de sa base, les deux extrémités de la cellule se rejoignant après en avoir fait le tour. La cellule photoréceptrice comprend une partie distale: le «bâtonnet» qui contient des structures lamellaires d'origine ciliaire et supportant probablement le pigment photosensible. Le corps même de la cellule est en relation avec le bâtonnet par un isthme ménagé au niveau d'affrontement des extrémités de la cellule pigmentaire. Le cristallin, situé immédiatement au-dessus du bâtonnet, est extracellulaire et en continuité avec la cuticule. Il semble être en relation avec une formation en cupule, de structure apparemment semblable, située à la base du bâtonnet. Il est entouré, successivement, par une cellule «pericristallinienne» en anneau et par la cellule pigmentaire.
Summary Each photoreceptor unit of Dasychone bombyx consists of a photoreceptor cell and a lens both enclosed in a collar composed of a «cellule pericristallinienne» and a pigmented cell. The rod which is supposed to be the photosensitive part of the photoreceptor cell is situated inside the pigmented cup and is connected by a narrow channel to the body of the cell, situated outside the pigmented cup. The rod is composed of membranous sacs of ciliary origin. The lens is extracellular and continuous with the cuticle. It seems to be connected with an extracellular cupule of the same morphological structure, located at the base of the rod.
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Sommaire Nous avons analysé le lait fraîchement prélevé du jabot des deux parents le matin à jeûn.Le poids sec de ce lait est très variable (de 3,6 à 32,2%). Celui du lait prélevé dans le jabot des jeunes est au contraire presque constant: 26,0%.Le lait de jabot ne contient d'autres hydrates de carbone que la ribose et la désoxyribose des acides nucléiques.La plus grande partie des protéines est formée par une espèce de caséine à faible teneur en phoshore.Il ne semble pas exister de différence entre la quantité de protéines contenue dans le lait des premiers et celui des derniers jours de la période de lactation, ni entre celui secreté par le mâle et celui secreté par la femelle.Les acides aminés libres et ceux contenus dans les hydrolysats ont été déterminés qualitativement.L'indice d'iode des lipides extraits à l'éther (70,65) est de beaucoup supérieur à celui des lipides extraits au méthanol-chloroforme (23,80).La composition du lait total, tel qu'il est fourni aux jeunes, est la suivante: eau 74,00%, cendres 1,37%, protéines 12,40%, autres substances azotées ± 1,32%, lipides 8,61%.
The composition of pigeon cropmilk
Summary The analyses performed on cropmilk freshly taken from the crop of both parents, lead to the following conclusions:the dry weight of this cropmilk is very variable (between 3.6 and 32.2 %); on the contrary the dry weight of the milk taken from the crop of the squabs is nearly constant (26.0%);the cropmilk doesn't contain any carbohydrates, except the ribose and desoxyribose from the nucleic acids;the bulk of the proteins is formed by a casein with a low phosphor content (Table 1);there seems to exist no difference between the composition of the cropmilk of the first and that of the last days of the lactation period, neither between that secreted by the male or that secreted by the female (Table 2);the free amino acids as well as those contained in the hydrolysates were determined (Table 3);the iodine number of the ether extracted lipids (70.65) is far superior to that of the lipids extracted by methanol-chloroform (23.80);the composition of the milk, as it is given to the squabs, is: water 74.00%, ashes 1.37%, proteins 12.40%, other nitrogen compounds ±1.32%, lipids 8.61%.
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J. R. Steffan 《BioControl》1962,7(2):181-188
Summary In this paper four new palearctic species ofTorymidae are described:Monodontomerus gladiatus andTorymus favardi from South of France,Glyphomerus signifer from Austria andPseudotorymus amethystinus from Algeria.Torymus favardi is a parasite of bothDryocosmus australis mayr andAndricus singulus (mayr), whereasGlyphomerus signifer has been bred from galls ofDiplolepis spinosissimae (gir.).   相似文献   

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The present work deals with the microfauna of small benthonic and planktonic Foraminifera from the Burdigalian stratotype of Aquitaine basin (France) and from a few outcrops in the stratotype vicinity showing the upper or lower boundary of the stratotype.Benthonic fauna is rich: more than 250 species divided in 92 genera have been collected. The most frequent are hyaline Foraminifera (Pararotalia, Elphidium, Asterigerina, Florilus, Virgulopsis, Bolivina). The miocene feature is more pronounced than in the Aquitanian stratotype.Planktonic Foraminifera are much less abundant:only 20 species. However, some of them authorize to place the stratotype (or its equivalent l. s.) in N5 Blow's zone and perhaps in the basel N6 zone.The figurations of many species are made withthe scanning electronic microscope.  相似文献   

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A skeleton of a Channid fish is reported for the first time from the European Lower Miocene. Because of the lack of any appropriate diagnostic character, it is nevertheless impossible to determine if it belongs either to the Asiatic genusChanna Scopoli or to the African one,Parachanna Teugels &Daget. For this reason, its palaeobiogeographical significance remains unclear. Otoliths (sagitta) that very likely belong to the same Channid species have been described from Illerkirchberg asChanna elliptica (vonSalis). They are compared to the sagitta from recent species of the generaChanna (Scopoli) andParachanna (Teugels &Daget). Their morphological characters are intermediate between those characterizing the sagitta of both genera.  相似文献   

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《Geobios》1988,21(1):73-80
enTwenty-seven samples have been collected in AshtartBasin (Pelagian Sea), along the core KST 100. Studies on ostracods species enables us to recognize four main associations from - 27 000 years to the Recent; the first can be linked to the Würm III regression and the other ones to the Versilian transgression.  相似文献   

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