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1.
M. Knoepffler-Peguy 《Helgoland Marine Research》1973,24(1-4):476-489
Resume 1. Comparaison du comportement et de l'évolution au cours d'une année de quelques pieds âgés et de quelques embryons deCystoseira méditerranéens (principalementC. mediterranea
Sauvageau 1912) cultivés parallèlement d'une part en pleine mer, d'autre part au laboratoire en milieu artificiel ou en aquarium.2. En pleine mer, l'évolution des échantillons âgés se déroule normalement. En aquarium, la chute des rameaux de printemps et la formation des rameaux d'automne sont d'autant plus précoces que l'éclairement est plus faible.3. Le développement et la croissance des embryons sont à peu près semblables en mer et au laboratoire, mais les «feuilles» caractéristiques apparaissent beaucoup plus tôt sur les individus cultivés en milieu artificiel. Les jeunes plantules nées en automne évoluent beaucoup plus rapidement que les plantules de printemps.
Wachstum und Entwicklung mediterraner Cystoseiren (Phaeophyceae-Fucales). Kulturversuche im Meer
Kurzfassung Etwa ein Jahr lang wurde die Entwicklung mediterranerCystoseira-Arten (hauptsächlich vonC. mediterranea) verglichen, die im freien Meer und im Aquarium bzw. im Laboratorium aufwuchsen. Es zeigte sich, daß Pflanzen vom natürlichen Standort auf dem Versuchsstand im freien Meer normal weitergediehen. Im Aquarium treiben — vermutlich wegen des schwächeren Lichtgenusses — die Frühjahrssprosse zeitiger aus, und die Herbstzweige erscheinen früher. Aus Eiern kultivierte Keimlinge entwickeln sich in künstlichen Nährmedien zunächst schneller, doch gleicht sich der Größenunterschied nach dem Umsetzen in das Meer oder Aquarium nach 6 Monaten aus. Die charakteristischen Blätter erschienen aber bei den im Laboratorium kultivierten Pflanzen früher als bei den Vergleichspflanzen im Meer. In einer Aufzucht aus Herbsteiern erscheinen die Blätter bereits im Februar, also zur gleichen Zeit wie bei den um ein halbes Jahr älteren Kulturen.相似文献
2.
《Geobios》1988,21(2):251-257
The Messinian coral reefs of Oranie (western Algeria) often contain determinable remnants of decapods (carapaces, chelae). Six species are mentioned, all of them for the first time from the Upper Miocene of Algeria. Further, a new species (Lachnopodus murdjadjensis) is proposed. This decapod association seems to be a characteristic reefdwelling one. Its affinities are discussed. 相似文献
3.
《Comptes Rendus Palevol》2003,2(6-7):597-605
Morphological fluctuations and heterochronies of Toxaster (echinoid, Lower Cretaceous). Several steps of the diversification of the spatangoid Toxaster are described with an analysis of six species distributed over the north-west Tethyan margin, and ranging from the Lower Valanginian to the Barremian. Morphological variation was investigated with the analysis of two parameters (angles), which allowed recognition of three modules on the test. Comparison of ontogenetic trajectories of two reference species (T. granosus kiliani and T. retusus) suggests a peramorphic heterochronic pattern. However, no peramorphocline can be attested when comparisons are extended to adults of the six species. Evolution among these species is partially driven by allometric changes in one module, indicating an important influence of size. On the temporal and spatial scale of the study, the evolution of Toxaster appears globally quite conservative. To cite this article: É. François et al., C. R. Palevol 2 (2003). 相似文献
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《Cryptogamie Algologie ☆》1999,20(4):301-344
This paper deals with the aerophytic Cyanophyceae from New Caledonia sampled by Prof. Dr A. Guillaumin from Paris, Dr M.G. Baumann-Bodenheim from Zürich, Dr H. Hürlimann from Winterthur and Prof. Baas Becking from Noumea. A total of 124 samples were studied, most of them collected on soil, stones, rocks and barks. The characteristics of these samples are given. Among species, varieties and forms, a total of 85 taxa were recorded. Among them three are new for science, Gloeothece neocaledoniense nov. sp., Hydrocoryne neocaledonica nov. sp. and Scytonematopsis neocaledoniense nov. sp. One new combination is proposed, Petalonema involvens var. elongata (Bourr.) nov. comb. 相似文献
6.
《Geobios》1988,21(5):567-609
The genus Pachyerymnoceras, with four new species,is described for the first time in Western Algeria. The genus first appears in the Middle Callovia (Coronatum Zone) as in Saudi Arabia. It is represented in the Saida region by uncommon P. praecox nov. sp. followed during the Upper Callovian (Athleta Zone) by specimens belonging to P. flamandi sp. nov., P. kmerense nov. sp. and P. saidense nov. sp. Every species is represented by a dimorphic pair.Pachyceratidae are put into Perisphinctaceae. If Pachyerymnoceras arises from Erymnoceras, a genus suddenly appearing during the Middle Callovian on northern and southern Tethyan borders, the origin of Erymnoceras is still unknown. Three phylogenetic hypothesis are considered here. Erymnoceras may have evolved during Lower Callovian: 1) from serpenticonic Tethyan Pseudoperisphinctinae like Choffatia (Subgrossouvria); 2) from Tulitids via ellipticoncic Bullatimorphites (Kheraiceras); 3) through a double lineage arisen in Subboreal and Tethyan platyconic Proplanulitids.Pachyceratids have a wide paleobiogeographic distribution in NW Europe and on the Tethyan margins. The genus Pachyerymnoceras evolves in Ethiopian Province of the Tethyan Realm. Some species migrate into Indo-Malagasian Province and others, through the south Tethyan border came to Europe were they are found restricted to Upper Callovian (Athleta and Lamberti Zones). Therefore this migration has a duration of two or even three zones. 相似文献
7.
《L'Anthropologie》2015,119(4):473-486
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. 相似文献
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《Geobios》1987,20(6):789-810
The micropaleontological and sedimentological analysis of the cuttings and core-samples extracted from a certain number of borings conducted seaside Casamance, western Casamance and eastern Casamance (fig. 1), enabled the researches to determine Casamance stratigraphy and paleoecology during the tertiary period. The microfauna gathered (foraminifera and ostracoda) makes it possible to characterize the biozones P1 to P15/P16 followed by the biozones N1/N2 to N14, bringing into evidence the existence of Paleogene and Neogene which are separated by a gap of changeable amplitude.The sedimentological study has revealed the presence of a certein number of landmarks and lithologic mineralogical sets which seem to be constant in the studied boring. 相似文献
9.
Denise Damas 《Cell and tissue research》1973,143(3):355-365
Résumé Le tégument de Glossiphonia complanata comprend, outre les cellules épithéliales banales, de nombreux organes particuliers ou organes de Bayer, regroupés essentiellement sur la face dorsale de l'animal. Ils sont formés par une cellule apicale saillante enchassée dans une cellule musculaire en anneau.L'ensemble de ces formations est étudié du point de vue ultrastructural. Des cellules épithéliales partent des fibres nerveuses afférentes, sans doute vecteur des perceptions de stimuli mécaniques de pression au niveau du tégument; la réponse se faisant sans doute par la contraction de la cellule basale de chaque organe de Bayer, innervée par des fibres nerveuses efférentes, entrainant la saillie de la cellule apicale. Le hérissement de ces nombreuses papilles du tégument dorsal pourrait être un signal perçu par le partenaire sexuel, chez cette Hirudinée à fécondation hypodermique.
Ultrastructure of the integumentary epithelium of Glossiphonia complanata (L.) (hirudinea): Epithelial cells and sensory organs of bayer
Summary The integument of Glossiphonia complanata, built up by epithelial cells, contains numerous particular organs (Bayer organs), mainly on the dorsal side of the animal. They consist of a protuberant apical cell, which is surrounded by a ring-shaped muscle cell. All the integumentary formations are studied from an ultrastructural point of view. From the epithelial cells issue afferent nerve fibres, considered as vectors of the perception of mechanical stimuli of pressure at the level of the integument; the response no doubt operating by the contraction of the basal muscle cell of each Bayer organ, innervated by efferent nerve fibres, bringing forth the protrusion of the apical cell. The erection of these numerous papillae of the dorsal integument might be a signal perceived by the sexual partner, fecundation occurring in this group of leeches under the integument.相似文献
10.
《Geobios》1988,21(6):773-785
The revision of the fossil fishes from the Lower Oligocene of Ronzon, Le Puy-en-Velay (Haute-Loire, France), leads one to give a more precise account of their main anatomical and meristic features. According to the rules of zoological nomenclature, the unique fish species known from this locality must be named Prolebias aymardi (Sauvage). Some palaeoecological characters of these fishes are specified. 相似文献
11.
Guy Vernet 《Cell and tissue research》1972,134(2):245-254
Résumé Lors de la régénération traumatique des yeux de Lineus ruber la différenciation biochimique des nouvelles cellules pigmentaires est séquentielle. On assiste à l'apparition successive des chaînes enzymatiques nécéssaires à la biosynthèse de porphyrine et de mélanine.Les études ultrastructurale et autoradiographique à haute résolution de ces phénomènes — montrent que la mélanisation s'opère au niveau d'organites cellulaires spécialisés (prémélanosomes, mélanosomes). La porphyrinogénèse se développe dans des vacuoles et organites d'origine golgienne qui participent également à la mélanogénèse.
Ultrastructure of photoreceptors in Lineus ruber (O. F. Müller)
Summary In Lineus ruber the biochemical differentiation of the new pigmentary cells is sequential during the reparative regeneration of the eyes. The enzymatic pathways for porphyrin and melanin biosynthesis appear successively.Ultrastructural and high resolution radioautography studies, show that melanization occurs in specialized organelles called premelanosomes, melanosomes and melanin granules. Prophyrogenesis occurs in Golgi vesicles which are also involved in melanogenesis.相似文献
12.
Anne-Marie Chevolot-Magueur Adrien Cave Pierre Potier Jean Teste Angèle Chiaroni Claude Riche 《Phytochemistry》1976,15(5):767-771
Four aromatic bromo compounds have been isolated from the ethanolic extract of Rytiphlea tinctoria after treatment with diazomethane: 2,4-dibromo-1,3,5-trimethoxy-benzene,5,6,3′,5′-tetrabromo-3,4,2′,4′,6′-pentamethoxydiphenylmethane, 5,6-dibromo-3,4-dimethoxy-benzyl alcohol and its ethyl ether. In addition to sterols, amino acids, this extract also contains quinonoid bromo-pigments which could play a rôle in photosensitisation of chlorophylls, a rôle normally taken by the phycobilins, in other Rhodophyceae. 相似文献
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Geomorphological investigations have been carried out in Camerota surroundings where marine microfaunas have been discovered. So, we can separate the Late Pliocene deposits from Calabrian and post-Calabrian levels. Preliminary palynological results show a vegetational evolution in relation with the climate. Leaf-remains give informations on the structure of the vegetation. 相似文献
15.
《Geobios》1988,21(3):269-305
The present statistical study of two Bajocian populationsof Isastrea from eastern France uses different methods of measurement taking into account the colonial character. The results of the univariate and the multivariate analyses together with direct observation of qualitative characters show that only two species are present in the samples: Isastrea bernardiana and I.tenuistriata. A new synonymy is suggested for the Bajocian species. Genera such as Andemantastraea All. and Parisastraea All. correspond to the common variation of Isastrea. The taxonomic position of other Jurassic Isastrea is examined. It is probably possible to use extreme morphotypes as stratigraphic markers owing to an eventual anagenesis.A comparison between the two samples denotes that the variation range or the mean value of some quantitative characters (number, thickness of septa, dimension of corallites, trabecular density) contributes to the paleoecological interpretation.The present paper emphasizes the necessity ofwell-defined species based preferably on population study, for a reliable generic definition. 相似文献
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Guy Vernet 《Cell and tissue research》1970,104(4):494-506
Summary The eyes of the Nemertean worm Lineus ruber are situated on the dorsal face of the animal in two lateral bands in front of the cerebral ganglia. There are 6 or 8 ocelli per animal enclosed in the cephalic parenchyme. They consist of a pigmented eyecup in which 50 photoreceptor cells are present. The photoreceptrice cells have:dendritic processes which are full of mitochondria, neurotubules, vacuoles and only one axial filament;a pericaryon with rough endoplasmic reticulum, a Golgi apparatus and few mitochondria.
Résumé Les yeux de la Némerte marine Lineus ruber sont situés sur la face dorsale de l'animal, en deux rangées parallèles à l'avant des ganglions cérébroïdes. On en dénombre 6 à 8 localisés dans le parenchyme céphalique. Ils consistent en une cupule pigmentaire entourant une cinquantaine de cellules visuelles qui rejoignent les centres nerveux supérieurs. Pour les cellules photoréceptrices on distingue:un processus dendritique riche en mitochondries, neurotubules, vacuoles et possédant un axe médian;un corps cellulaire où l'on trouve du réticulum endoplasmique rugueux, un appareil de Golgi développé mais peu de mitochondries.相似文献
19.
Jean-Pierre Thieuloy 《Geobios》1977,10(3):395-461
The boreal Ammonites (and the more or lessphylogenetically related ones) of the southeast France (Tethyan Realm) are described and figured. 24 forms are refered to, or compared with, previously identified species. 3 are left under open nomenclature, and 7 are new ones. Two new subgenus: Julianites (Paquiericeras) and Lemurostephanus (Olcostephanus) are also introduced.Their biostratigraphic position in the Frenchzonal scheme is detailed. Their contribution to the establishment of correlation between the Boreal and Tethyan provinces is stressed.The most interesting feature is the identification of a Prodichotomites horizon just below the Verrucosum zone, allowing comparison of the definition of the Lower-Upper Valanginian boundary in these two paleobiogeographic realms. 相似文献
20.
《Annales de Paléontologie》1999,85(2):155-171
Peltoceratoides athletoides (Lahusen) is currently used in the Tethyan domain (Submediterranean province) as an index-species for two separate biochronological units: one a horizon near the top of the Callovian, the other a zone at the base of the Oxfordian. Paleontological revision of the species, from specimens collected in situ in South East France and in Normandy shows that species is strictly localized in the lowermost Oxfordian. Consequently, the Callovian horizon, originally defined in Anjou, should be renamed the Schroederi horizon. The usefulness of Peltoceratoides athletoides as an indicator of the first Oxfordian zone in the Tethyan domain, the counterpart of the Mariae zone, is confirmed. In addition, strict localization of the species makes it is possible to define a subzone and a horizon for the base of the Oxfordian, which are the boreal equivalents of the Scarburgense subzone and Scarburgense horizon. These new data contribute to build a standard West Tethyan scale entirely independant of the boreal zonation for the Upper Callovian and Lower Oxfordian. 相似文献