Répartition stratigraphique et biozones des kystes de dinoflagellés au passage Jurassique moyen–Jurassique supérieur (Bathonien supérieur–Oxfordien inférieur) dans le Bassin de Guercif,Maroc nord-oriental

Despite the stratigraphical significance of dinoflagellate cysts as reliable markers for correlating and dating Jurassic–Cretaceous strata, investigations into this palynomorph group in the southern Tethyan Realm, specifically northwest Africa, are sparse and somewhat parochial. Most research on Jurassic dinoflagellate cysts is focussed on European depocentres in the Boreal and Sub-Boreal realms. This study is on biostratigraphical data from two petroleum boreholes (MSD1 and KDH1) drilled during 1985 in the Guercif Basin, northeast Morocco by ONAREP (Office National de Recherche et d’Exploitation Pétrolier), now ONHYM (Office National des Hydrocarbures et des Mines). These boreholes penetrated a thick siliciclastic succession, attributed to the Middle and Upper Jurassic, below Miocene marls. Over sixty dinoflagellate cyst taxa were identified. Four dinoflagellate cyst biozones, named GI to GIV, are established for the late Bathonian to early Oxfordian interval. These biozones are defined on the basis of the first appearance datum (FAD) and/or the last appearance datum (LAD) of some biomarker taxa which have wide geographical distributions. These are: Ctenidodinium combazii and Ctenidodinium sellwoodii for the GI Biozone (late Bathonian–early Callovian); Ctenidodinium continuum and Meiourogonyaulax caytonensis for the GII Biozone (middle Callovian); Gonyaulacysta centriconnata and Wanaea thysanota for the GIII Biozone (late Callovian–earliest Oxfordian); and Liesbergia liesbergensis and Systematophora penicillata for the GIV Biozone (early Oxfordian). These biozones are correlated to those already established for the respective intervals in other palaeogeographic regions, such as the Boreal, Sub-boreal and Tethyan realms.     

Le Paléolithique supérieur de la région centre de l’île de Honshû

Tokai area is situated in the middle of Japan and has various configurations of ground. The eastern area has thick natural layers with volcanic ash which has been supplied from Mt. Fuji. About five chronological stages of Paleolithic culture from trapeze and edge-ground axe culture to microlith culture through backed blade culture have been found in the layers. These stages of Paleolithic culture are indicators of chronological studies in Tokai area. On the other hand, it is difficult to advance chronological studies in the middle east, middle, and west areas, because they have little thickness of layers with volcanic ash. However, different Paleolithic artifacts are found in top and bottom layers which put the AT layer between at Tsubakibora Site in Gifu Prefecture, and they have helped very much chronological studies of Paleolithic culture in the west area. Here is the first result of Paleolithic studies in Tokai area with artifacts which have been found on the forth layer of scoriae at Idemaruyama Site are dated about 35,000 years, one of the oldest Paleolithic culture in Japan. In addition, some lines of pits which were dated 30,000 years were found at Hatsunegahara Site, and they provided valuable data to study Paleolithic hunting. Finally, a holed pendant which had 10 notches on one side was unearthed from Fujiishi Site, and it was dated 19,000 years ago. At Terada and Hino Site, a flat big stone which had carvings was found, though the shape and use were seemed to be different from the pendant at Fujiishi Site.     

La technique de débitage au Paléolithique supérieur de l’archipel du Japon

The representative debitage technique is the one of the culture of knife-to-back in the name of the superior Paleolithic of Japan. She/it can be he divided in two, the one of the first half and the one of the second half. The first corresponds at the time of apparition, either to the stage of launching of the technique of debitage laminaire whose debitage didn’t provide elaborate blades being little successive. As for the stage of fortifying of the debitage laminaire, the industries lithic to knife-to-back of the Sugikubo type developed themselves in the oriental Honshû. With regard to the region of Kantô to the second half of the first where the knife-to-back of Moro type mingled equally with those while shaping on the blade. To the recent stage of development, one can note the industry lithic to knife-to-back of Moro type is based on the technical very blady in the western Japan. Succeeding in the second half of the superior Paleolithic that the technique of debitage of Sétoüchi developed itself in this part whose debitage is characterized by the strut oblong in wing, are the transverse blades These gotten supports used especially for making the knife-to-back of Koü type while spilling country-wide. To the second recent half, the technical blade of Sunagawa type took place in all regions of Japan except the inshore regions of the Interior Sea of Séto and the region of Kinki (Kyoto-Osaka).     

Le Paléolithique supérieur du plateau de Musashino et les hauteurs de Tama aux alentours de Tokyo

The Upper Paleolithic at the region of Tokyo that itself called also the Japanese Preceramic age that possesses a large number of excavations and those studies during the dawn of Paleolithic study in this country. The Preceramic age or the Upper Paleolithic has been raised the curtain by the discovery of a piece in obsidian, in 1949, in the loam of Kantô, at Iwajyuku site. We explain above, on the stratigraphy, the chronology and the situation and the evolution of site around Tokyo. It is a region to the highest density of the Upper Paleolithic sites in the archipelago of Japan and the systematic excavation according to the stratigraphy of loam formation has been done for the first time in the country. The authentic chronology has been proposed to the years 60s that based on the discovered lithic industries on the plateau of Sagamino and Musashino. This chronology was used for a long time that it made a role like a norm for the whole country. Not only, after again an accumulation of the research until the present, we understand the different periodic activities between the Tama hills, the plateau of Musashino, the plateau of Sagamino, the North of Kantô district and the plateau of Simôssa. Of course, there is a complex circumstance that the apparition and the disappearance of various types of lithic instruments are different, and every type tools are not universal around Tokyo area, in the district of Kantô. The final of Upper Paleolithic on the archipelago of Japan divides extensively in two parts East-west that the East of Japan is characterized by the well-organized aspect microlithic tendency and the west is characterized by the trend of microlite, trapeze and tool on transverse blade. In such general tendency, the region of Kantô is located therefore in the center on the archipelago of Japan that it showed sets of every different time.     

Découverte de microfaunes de l'Albienmoyen et supérieur dans la vallée de Joux (Jura Vaudois,Suisse)

The discovery of Foraminifera and Ostracodesin the dark green, sandy-glauconitic marl clay in the Joux Valley (in the Vaudois Jura) suggests to date these sediments Middle and Upper Albian. The Ostracode associations are similar to those found in the Paris Basin, but different from those which characterize the subalpine region.     

Charles de Gerville et les premiers restes de Plesiosauria signalés dans le Jurassique inférieur de France (Hettangien,région de Valognes,Manche)

The historian, archaeologist, and naturalist Charles de Gerville (1769–1853) reported as early as January 1816 the presence of fossil bones in the quarries of the region of Valognes, in the department of Manche. These quarries exploited the “Calcaire de Valognes” and the underlying “Argiles et Calcaires d’Huberville”, both formations dated as Lower Hettangian (Lower Jurassic). De Gerville communicated to Jacques-Louis-Marin Defrance a watercolour drawing of one of these fossil bones, discovered in July 1820, in which it is possible to recognize a plesiosaur femur. This femur, as well as a fragment of rib and three vertebrae of Plesiosauria from de Gerville's collection, was then figured in a publication by Arcisse de Caumont, in 1825. The plesiosaur femur was later acquired by Pierre Tesson of Caen, who owned one of the most important collections of fossils in Normandy. The Tesson collection was later purchased in 1857 by the British Museum (now The Natural History Museum, London), where the femur has been rediscovered. This specimen is the first known plesiosaur specimen ever discovered in the Lower Jurassic of France, before the genus Plesiosaurus was established upon material from the Lias of southwestern England. One of the vertebrae figured by de Caumont has been rediscovered in the “Muséum Emmanuel-Liais” (Cherbourg-en-Cotentin), which had acquired part of de Gerville's collection. The interpretation of the “fossil bones of Valognes” by Georges Cuvier, Henri Marie Ducrotay de Blainville, Arcisse de Caumont, Jacques-Amand Eudes-Deslongchamps and Constant Duméril is revealed through unpublished documents.     

Des Normapolles du Crétacé supérieur de Piedras Negras (Coahuila,Mexique)

Normapolles pollen grains found in the Upson andSan Miguel Formations of northeastern Mexico extend the atlantic Normapolles Province of North America to the northern part of Middle America. Besides, since one admits the Lower Maastrichtian age of the Olmos Formation, the biostratigraphic extinction of the group appears regionally earlier than in the Atlantic Coastal Plain.     

Ultrastructure du lobe postérieur de l'hypophyse du rat et ses modifications au cours de l'excrétion de vasopressine

Résumé Le lobe postérieur de l'hypophyse a été examiné sur coupes ultrafines chez 45 rats (24 normaux, 17 déshydratés respectivement 1, 2 et 4 jours, et 4 anesthésiés à l'éther), après fixation au glutaraldéhyde ou selon la méthode de Karnovsky, post-fixation osmiée et double contraste à l'acétate d'uranyle et au citrate de plomb. Des fibres neurosécrétoires sombres et claires sont reconnaissables, mais les données manquent encore pour interpréter cette différence. Des densifications juxta-membranaires sont observées dans les terminaisons neurosécrétoires là où se trouvent des amas de microvésicules. Des fibres neurosécrétoires traversent parfois des pituicytes; il est aussi souvent observé des fibres, chargées de granules, libres dans un espace péricapillaire. Les espaces péricapillaires, ramifiés en tous sens loin des vaisseaux, développent une large surface de contact avec les extrémités nerveuses et les prolongements de pituicytes.Dans des conditions techniques bien contrôlées, la déshydratation n'entraîne pas de modifications appréciables des granules de neurosécrétat après 24 h. Ensuite les granules sont diminués en nombre, de façon très considérable le 4e jour; mais les granules restants ont un contenu dense normal; jamais il n'a été observé d'aspects de granules vides . Après anesthésie prolongée à l'éther, il n'y a aucune modification visible ni du nombre, ni de la densité des granules. Ces observations sont discutées quant au mécanisme de l'excrétion de vasopressine; elles sont en faveur de l'existence de deux pools hormonaux, l'un libre et rapidement disponible, l'autre plus fortement lié et certainement contenu dans les granules jouant le rôle de réserve. Toutefois un mécanisme d'exocytose granulaire ne peut être formellement exclu.

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Ultrastructure of the rat's hypophysial neural lobe and it's changes during vasopressin release

Summary Hypophysial neural lobes of 45 rats (24 controls, 17 dehydrated resp. 1, 2 and 4 days, and 4 ether anesthetized) were fixed either with glutaraldehyde or according to Karnovsky and post-fixed in osmium tetroxyde; ultrathin sections were stained by uranyl acetate and lead citrate. Dark and clear neurosecretory fibres were observed, but sufficient data are still lacking for a valuable interpretation of these aspects. Juxta-membraneous densifications are visible in limited areas of neurosecretory terminals where clusters of microvesicles are present. Neurosecretory fibres happen to be completely encircled by pituioyte cytoplasm; fibres loaded with elementary granules are frequently encountered running free in a pericapillary space. Pericapillary spaces stretch out branching far away from vessels, resulting in a widespread contact with nerve terminals and pituicyte processes.In accurately controlled technical conditions, dehydratation does not result in any noticeable change of neurosecretory granules after 24 h. A decrease of the number of granules follows and is extremely conspicuous after 4 days; though, remaining granules keep a normal dense content, and aspects of empty granules have never been observed. After prolonged ether anesthesia, no visible change either in number or electron density of granules was observed. These findings are discussed in consideration of the mechanism of vasopressin release; they support the hypothesis of two hormonal pools, one of which would be free and rapidly available for release, the other being more tightly bound and certainly located in granules representing a storage site. Though granular exocytosis cannot be absolutely excluded.

Travail effectué avec l'aide, en matériel et en assistance technique, du Centre National de la Recherche Scientifique. — Nous remercions particulièrement Mme J. Bottini pour son aide précieuse dans la préparation du manuscrit et Mr. B. Dutillet pour sa participation aux contrôles en microscopie optique.     

Nouvelles espèces de Madréporaires dans le Kimméridgien supérieur du Jura (France)

The study of an Upper Kimmeridgian madreporarianfauna collected in the southern french Jura (between Valfin and Belley), allowed: 1) to describe five Scleractinian new species: Mitrodendron biennensis nov. sp., Hexapetalum nemorosum nov. sp., Thalamocoenia gironensis nov. sp., Cryptocoenia stelliserrata nov. sp., Columnocoenia miniflora nov. sp. and a new variety of Heliocoenia (Kobycoenia) claudiopolisensisBeauv., 1964, characterized by its small calices; 2) to modify the diagnosis and the systematic position of the species Baryhelia crassa (de From.) which was created as Heterocoenia crassade From.; 3) to increase of a new species the genus Hexapetalum only known, till now, by its Stramberg Tithon type-species; and 4) to give some palaeoenvironmental conclusions = the Upper Jurassic reef formations in the Southern Jura grew in shallow water characterized by an abundant carbonate sedimentation. Genera associations and distribution confirm the presence, between Oyonnax and Belley, of a low energy area, protected by a barrier reef and, northern of this barrier, of a higher hydrodynamic environment.     

Innervation du muscle rétracteur antérieur du byssus (ABRM) de Mytilus edulis L.

Summary Detection of nerve structures containing 5-HT were described in the anterior byssus retractor muscle (ABRM) in Mytilus edulis L. after using the fluorescence microscope technique of Falck. We are able to confirm our previous results and assumptions given by histology and electron microscope studies: the neuromuscular en passage junctions, largely distributed within the ABRM, contain 5-HT.     

Hommes et climats au Paléolithique supérieur dans le bassin de la Somme (France)

Nearly 40 years of intensive research conducted in the Somme basin has demonstrated the discontinuity in the human occupation of the area during the Upper Palaeolithic. The northern position of the Somme basin within the loessic region appears to be an explanatory factor in this discontinuity, the nature of which increasingly appears related to climate and environmental factors. Archaeological occupations have been systematically attributed to phases of warming or climate improvement. On the other hand, an absence of human occupation has been consistently observed during the coldest periods. The extreme poverty of the biomass contemporary to the loessic deposits of the Upper Pleniglacial could partly explain this discontinuity specific to the far northwest of Europe (southern England, northern Belgium, Netherlands, and northern Germany). Although only 150 or 200 km away, the southern Paris Basin, which is located on the fringes of the loessic region of northern France and Normandy, presents a more continuous human occupation, which appears to have benefitted from more favourable conditions.     

Suoidea du Miocène inférieur de Laugnac (Lot-et-Garonne, France)

The fossil vertebrate locality of Laugnac is the type locality of the Neogene mammalian zone MN2b. It has yielded many remains of Suoidea belonging to two different genera.Xenohyus venitor is characterized by its large size and especially its large central upper incisors, I1/ and I2/. It is quite difficult to know its phyletic relationships because the material is not abundant.Hyotherium cf.meisneri is more abundant with a quite good skull, pieces of skull, jaws and isolated teeth. It belongs to a peculiar lineage different from that ofH. major from Saint Gérand-le-Puy, France. It has some similarities withAureliachoerus aurelianensis from later geological levels (MN3-MN5).     

Nouvelles espèces de dasycladales du crétacé inférieur de provence (S.E. France)

In the Lower Cretaceous of Provence Cylindroporella faronensis n. sp. and Cylindroporella massiliana n. sp. represent small size species with a limited number of branches. The former ranges from the Middle (or Lower p.p. ?) Berriasian to the Lower Valanginian, the latter is found in the Lower Hauterivian, but could appear earlier in other regions. Clypeina isabellae n. sp. is also a small size form with a fibrous, yellowish microstructure, close to Clypeina sulcata, it is restricted to the Middle (or Lower p.p. ?) and Upper Berriasian. Besides their biostratigraphic and palaeobiogeographic potential value this material from Provence is also interesting from an evolutionary point of view. At generic levels it shows distinctive patterns relatively to the “Cope law”.     

Les crocodiliens fossiles du Jurassique moyen et supérieur de Bourgogne

The middle and upper Jurassic limestones of Côte-d'Or (France) contain some crocodilian remains referred to the genera Teleidosaurus, Steneosaurus, and Metriorhynchus. Their preservation allows a determination at a specific level only for Teleidosaurus gaudryi (Lower Bathonian), Steneosaurus larteti (Upper Bathonian), S. heberti and S. cf. intermedius (Middle Oxfordian). Sedimentological evidence shows that Steneosaurus and Teleidosaurus are found either in very pure limestones sedimented on an epicontinental platform, in a very calm and sheltered environment, in the intertidal or supratidal zone, often associated with subrecifal facies; or in the infratidal zone, more distinctly subjected to open-sea influences (deposits, currents, reworkings). Specialised Metriorhynchidae such as Metriorhynchus are completely absent in the former type of sediment but are present in the later. One may infer, considering anatomical evidence (no dermal armour, caudal fin…) that Metriorhynchus was better adapted to swimming and rather lived in the open sea. The Teleosauridae preferred very shallow or temporarily emerged places, where they could move around thanks to their limbs which were still capable of walking on land; however, this did not prevent them from going out to sea, where the habitats of both families probably largely overlapped.     

Découverte d'une faune de vertébrés dans l'Oligocène inférieur de Vayres-sur-Essonne (bassin de Paris,France) : biodiversité et paléoenvironnement

The new rich vertebrates deposit from the Lower Oligocene, at Vayres-sur-Essonne (Essonne, France), contains 34 marine and seven continental taxa, 17 taxa being recorded for the first time from the Paris Basin. The richness of the ichtyofauna is higher than in anyone of the Parisian Oligocene deposits and equals the one of the ‘Argiles de Boom’ (Belgian Rupelian). Its affinities with the septentrional ichtyofauna is confirmed, meridional elements being rare. The terrestrial fauna, the oldest known from stratotypical Stampian (base of the Upper Stampian) shares affinities with the one of Montalbán and attests the occurrence of nearly freshwater environments. To cite this article: D. Merle et al., C. R. Palevol 1 (2002) 111–116.     

Interprétation paléogéographique des données palynologiques du site du Paléolithique supérieur de Mezhyrich (Ukraine)

The results of palynological study of the Upper Paleolithic Mezhyrich site in central Ukraine are presented. Four local pollen zones were identified. The results of the palynological investigations allow us to hypothesize that the plant cover during Upper Paleolithic had a mosaic structure. The pollen record shows the presence of a few tree species with the predominance of herbaceous plants. We suggest that the river valleys and other local favorable sites were natural refugia where forest elements could survive even during the Last Glacial Maximum. These favorable landscapes to the existence of prehistoric hunters may have persisted during the Last Pleniglacial.     

Trace nouvelle de locomotion de Chélonienet figures d'émersion associées dans les calcaires lithographiques de Cerin (Kimméridgien supérieur,Ain, France)

The first tetrapod Vertebrate track discovered in the late Kimmeridgian lithographic limestones of Cerin (Ain-France), is descrbed as a new ichnospecies, named Chelonichnium cerinense. The characteristics of the track, which is about 7 m long, suggest that it was made by a large Chelonian, but none of the fossil turtles known so far from Cerin is likely to be the author of these footprints. The ground on which the animal walked was apparently very wet, superficially soft, and sloping. Moreover, this track is associated to soft sediment slides, confirming emersion and slope. The depositional environment is interpreted as a platform located behind a «ribbon of islands. This irregular surface was at times emerged and terrestrial tetrapods could then leave tracks on the superficial layer.     

Découverte des sites du Paléolithique inférieur au Nord de l’Arménie

For a long time, the scientific community assumed that the Acheulean culture was expressed on the territory of the Armenian Plateau as well as in the neighboring regions of the Caucasus only by its late phase; therefore, it appeared in the second half of the Middle Pleistocene. In recent years, the Armenian-Russian mission has discovered and studied much older Acheulean industries sites, located in northern Armenia (the Lori intermountain Depression). These industries, represented by archaic type tools (large hand axes, picks, choppers, chisel-like tools, scrapers, points, etc.), are discovered in three deposits of origin of proluvial genesis. In the Karakhach site, this type of industry is deposited in the lower levels of volcanic tuff and below; the U/Pb study of this level of tuff proposes a series of dates, assigned to the time interval between 1.944 + 0.046 and 1.75 + 0.02 Ma. The paleomagnetic study demonstrated the inverse polarity on the tuff and the normal polarity of the underlying deposits; in correlation with other dating, this fact allows to attribute the Acheulean layers of the site of Karakhatch to the Lower Pleistocene, in particular to the Oldoway episode and to the Upper Matuyama time period. The estimated age and the techno-morphological characteristics of the tools indicate the Lower Acheulean period. The dating of the Muradovo site does not seem possible, however its very old industries and the archaeological layers, where they were discovered, find equivalents in the layered layer, surmounted by tuffs, of the Karakhatch site. The Kutran I site presented a paleosol sequence with similar Acheulean tools (hand axes, picks, choppers, etc.). Its oldest layer is older than 1.5 Ma, the upper layer is attributed to the early Middle Pleistocene; this fact means that it is possible to speak of the Lower Acheulean and of its transition to the Middle Acheulean period. The specific character and the age of the Lower Acheulean of Armenia admit that it could have formed independently of the Lower Acheulean of Africa, whose estimated age does not rise before 1.76 Ma. It should also be noted that on the neighboring territory of Georgia about the same time when appeared the Acheulean culture in Armenia, the Oldowan Dmanisi site already existed.     

Découverte de faunes d'Ammonites de la zone à Platynota(Kimméridgien inférieur) dans les Monts de Chellala (avant-pays Tellien,Algérie); Conséquences stratigraphiques et paléogéographiques

In Chellala mountains (Seba el Abiod), in Western Algeria, new biostratigraphic data, based on Ammonites, allow characterize, for the first time in North Africa, the Platynota zone with the species-index Sutneria platynota. This species was known, to the present time, only in the South European border. These new biostratigraphic data show the diachronism of flyschoid facies. They do not exceed middle Oxfordian in the Tlemcenian zone; on the contrary they go up to lower Kimmeridgian in the preatlasic zone.