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1.
In the studied area, on the southern slope(«Ossa-Morena Zone) of the Sierra Morena (Spain) the Silurian and earliest Devonian (Lochkovian = approximately Gedinnian) consist of about 130 m of black, argillaceous, largely euxinic graptolitic slates, which, by the intermezzo of the dark «Limestones with Orthoceras and Scyphocrinus (late Ludlow and Pridolian), are divided into two inequal units, namely the Lower and Upper Graptolitic Slates. The occurence of 21 Graptolite zones and horizons was established, starting off with the basal Llandovery (A. acuminatus zone) and ending up with the Upper Lochkovian (M. hercynicas zone). This condensed tripartite graptolitic sequence, both lithologically and faunally, compares closely with the typical development of the Palaeotethys, as known from Thuringia, Carnic Alps, Sardinia and Northwest Africa. Certain graptolite species and details of the graptolitic succession (for instance across the Wenlock-Ludlow junction) that were hitherto known only or essentially from Thuringia, are recognized also in southern Spain.  相似文献   

2.
Cabuamine is identified as O-methyl-hydrogeno akuammine.  相似文献   

3.
Paleogene sedimentation in the Alpes Maritimes and Alpes de Haute Provence regions is composed of one complete sedimentary sequence. This sequence begins with the continental Formation from Microcodium and continues with the Cerithium layers, the Calcaires Nummulitiques and the Marnes Bleues, which are overlaid by the turbidites of the Grès d’Annot Formation. Sedimentation starts in the Nummulites perforatus zone close to the base of ‘the Truncorotaloides rohri zone (P 14) and ends in the Cassigerinella chipolensis-Pseudohastigerina micra zone (P 18) and the NP21 zone in the upper part of the Grès d’Annot. More biomarkers were used in order to define a more detailed local biozonation (biozones AMP 1 to AMP 7). Four local zones were also defined by the last occurrence of Nummulites millecaput and N. perforatus-N. ptukhiani and then by the first appearance of N. retiatus (AMGF 1-4). The evolution of benthic foraminiferal assemblages shows an increase in bathymetry from the internal platform in the Cerithium layers to the calcareous platform with large foraminifers, then to the external platform and the deep offshore environment of the Marnes Bleues and Grès d’Annot. Low faunal diversity in the Grès d’Annot together with the predominance of agglutinated species indicates a poorly oxygenated, organic rich and turbidite environment. Seven steps (SD 1 to SD 7) in the Eocene marine transgression are shown from East to West by detailed local biozonation and sequence analysis. Grès d’Annot sedimentation is also diachronous, beginning within the Truncorotaloides rohri zone (P 14, AMP 1) in the East and ending within the Pararotalia opima opima zone (P 20, middle Rupelian) in the West (Barrême). Small foraminifer Paleogene fauna from the Alpes Maritimes and Alpes de Haute Provence was studied from 400 samples. It is composed of 378 species. Two new taxa are proposed: Fissurina niceana n. sp. and Globocassidulina alpina n. sp. The species from the Escarène and Gorbio neighborhood described by M. von Hantken (1884) were re-examined.  相似文献   

4.
Remains of vertebrates of Villafranchian age have been found in the Nuraghe Su Casteddu (Nuoro, Sardinia) formation. The fossiliferous layer contain a rich fauna of continental molluscs. The composition of the vertebrate fauna is as follows: Rana sp., ? Coluber sp., Aves indet., Episoriculus aff. gibberodon PETENYI, Talpa sp., Chiroptera indet. and Rodentia indet. It is the first discovery of Villafranchian vetebrates in Sardinia.  相似文献   

5.
Jacques Poncet 《Geobios》1976,9(3):345-351
A hypothetical model is proposed as an explanation of the morphogenesis of Renalcis thalus (calcareousalga). The thalus, as we can observe it, would originate from a colony of algal filaments growing in tuft, whose calcification would proceed in two stages. the formation of the micritic cortical zone would take place the alga being alive, whereas the sparitic internal zone would result from the filling up of a cavity by calcite, this cavity being the result of non calcification of the filaments at a certain depth in the tuft.An affinity with present Rivulariaceae is suggested, thus giving a support to the attribution of genus Renalcis to Schizophyta.  相似文献   

6.
The study of 15 species of ostracods from the Turonian of Provence is especially concernedin this paper; two new species are proposed: Mauritsina provencialis nov. sp. and Spinoleberis ectypus nov. sp.Two associations can have been recognized: one in the marly lower Turonian, theother in the zone of transition from the lower to the upper Turonian.These ostracods are replaced in the general stratigraphic context of the country and some comparisons can have been made with others countries.Some ecologic and paleogeographic remarks are proposed to contribute for a betterknowledge of the paleoenvironments.  相似文献   

7.
This review gives a synthesis on the present knowledge on the use of several electrophoretic markers in examining speciation and taxonomy in baboons (genus Papio, Mendrillus and Theropithecus). In the various species studied, the amplitude of variation is small and the average rate of individual heterozygosity low; this seems partly due to the inbreeding which occurs within the groups. In these sub-populations, and when the frquencies are in equilibrium, it is possible to calculate the number of genetic migrants by generation between groups, which averages 3–18% according to species. The genetic distances between species allow one to establish in the genus Papio that the species P. hamadryas is the most differentiated and on the whole these species are comparable to geographical races of a polytypic species according to the measures obtained. Calculation of electrophoretic distances shows tht within Papio both P. papio and P. anubis are indistinguishable and that the three other species. P. cynocephalus, P. ursinus and P. hamadryas, diverge from this basic group. According to these criteria, both Mandrillus species diverge on the average of 30% of their genes, and according to the paleontological dates of divergence between Papio and Theropithacus, Papio would have appeared approximately 3.5 million years ago, a date in agreement with the information obtained from fossils. The electrophoretic study of inter-specific hybrids allows the intensity of the migratory flux betwen the different groups of Papio anubis and P. hanadryas in natural conditions to be calculated, and shows a partial inhibition of the paternal component of hybrids P. anubix × P. cynocephalus. It is concluded that two interesting research problems are the study of inbreeding in the different groups, and the influence of the genetic regulation in the evolution of various species. The evolution of different species within the group seems to constitute an excellent animal model from the diversification of fossils hominids during the Pleistocene epoch.  相似文献   

8.
9.
In both lupin and broad bean, the root lipids contain paraffins, triglycerides, diglycerides, free fatty acids and polar lipids (phospholipids and galactolipids). The polar lipids and the triglycerides are the more abundant classes. The root galactolipids are mono- and di-galactosyldiglycerides; two steryl glycosides are also present. The phospholipids in both species are: phosphatidylinositol, phosphatidylcholine, phosphatidylglycerol, phosphatidylserine, phosphatidylethanolamine, diphosphatidylglycerol and phosphatidic acid. This last phospholipid represents 8·3% of total lipid phosphorus in Lupinus against 2·3% in Vicia. The other acidic phospholipids represent 30·4% in Lupinus against 20·9% in Vicia. The lipids of Lupinus are rich in linolenic acid whereas those found in Vicia are richer in linoleic acid. The various subcellular fractions prepared from the roots of both species have an homogeneous lipid composition, reflecting exactly that of entire cells. The calcium passive fixation capacity in microsomes and mitochondria of Lupinus roots is more important than that in the same organelles of Vicia faba roots. Thus a relationship is suggested between the amount of phospholipids in membranes and the passive fixation of calcium.  相似文献   

10.
Numerous fragments of spatangoid echinoids have been discovered in the Pliocene deposits of Challans, in Vendée (western France). In spite of the fragmentary data of the samples, a reconstitution of a complete test could be realized using the different fragments and their symetrization. The general shape of the test, and its architectural and ornemental characters allow establishing the presence of the genus Spatangus in western France during the end of Neogene. It allows to precise the biogeography of the genus Spatangus and of the morphological group S. (S.) purpureus on the Atlantic coast after the Messinian crisis. The Pliocene species is compared to the Miocene Spatangus (Phymapatagus) brittanus, abundant in Anjou, Brittany and Touraine. This older species was refered to the subgenus Phymapatagus according to the presumed lack of primary tubercles on its posterior interambulacrum. The discovery of well-preserved specimens, with primary tubercles on every parts of the test, in the Middle Miocene of Brittany allows to refute this subgeneric distinction and to refer the species brittanus to the subgenus Spatangus (Spatangus). The presence of this subgenus in western France is finally confirmed from Middle Miocene to Pliocene.  相似文献   

11.
The genus Cibaster Pomel, 1883, with its type species Cibaster bourgeoisanus (d'Orbigny, 1853), has poorly diagnostic characters. So, authors comprise this genus as Cardiaster Forbes, 1850, or as Offaster Desor, 1858. The study of numerous specimens of Cibaster bourgeoisanus, from the Coniacian of the “Craie de Villedieu” in the stratotypical region, demonstrates that this species is paedomorphic compared to Cardiaster, with juvenile pore-pairs and a shallow frontal groove. The plastron structure is derived from the pattern found in Pseudholaster Pomel, 1883. A close relationship between Pseudholaster and Cibaster is probable, with Protocardiaster Smith and Wright, 2003 as intermediate. Cibaster is clearly distinct from Offaster, because this last genus have a meridosternal plastron.  相似文献   

12.
Cell differentiation and acid-soluble sulfhydryl compounds in the root of Lens culinaris. Med. — The content of acid-soluble sulfhydryl compounds (SH + S-S) is determined amperometrically in tissues of the Lens root. Two distinct zones are analysed: first the meristematic one (0 to 1.6 mm from the tip) and secondly the elongating one (1.6 to 3.7 mm). Measurements concerned the first 80 hours of the root growth. SH/S-S ratio is minimum in the meristematic ZONE. Connections seem to exist between the growth rate and the amount of SH compounds in the elongating zone. These facts suggest that the increase of cytoplasmic SH is associated with the reduction of protein-disulfur-bridges, which account for t he intermicrofibrilar bindings in the cell wall. The effects of auxins (indoleacetic acid and naphtylacetic acid) treatments are also studied. They are strictly localized in the apical zone and their intensity depends upon the auxin concentration. SH-level is rising: this is due partially to a reduction of acid-soluble S-S.  相似文献   

13.
The Villalba Alta and Arquillo 3's populations are considered as archaïcal diachrons of Mimomys occitanus morphologically intermediaire between Prosomys insuliferus from Vendargues and Mimomys occitanus from Sète (Ruscinian, zone MN 15; 3,5-4 My).  相似文献   

14.
The group density of four species of cave fishes (Caecobarbus geertsi, Barbopsis devecchii, Astyanax gen. and Uegitglanis zammaranoi) and of two taxonomically related epigean species (Barbus conchonius and Hyphessobricon scholzei) was measured tridimensionally in an experimental aquarium, using a video recorder and a mirror inclined at 45° placed on top of the aquarium. The experiments were conducted in dim red light. The illumination was continuous in the case of cave fishes. For the epigean forms a 12/12 LD cycle was superimposed using dim achromatic sources. The relative positions of individuals within their own specific group were registered hourly during a week (168 h). Results show that in cave forms, the mean density of groups falls within the theoretical limits of random distribution values in all cases, whereas epigean species display a non-random aggregation tendency.  相似文献   

15.
Daniel Melin 《Phytochemistry》1975,14(10):2193-2197
Phenylalanine is the precursor of the cinnamic acids and coumarins in the stems and leafs of P. graeca L. Esterification of p-coumaric acid by quinic acid is required before oxidation to chlorogenic acid. In our experiments, we did not obtain radioactive flavonols from 14C phenylalanine. PAL activity varies as a result of light and temperature in the same manner as the level of flavonoids (especially the phenolic acids). This enzyme, therefore, plays a regulatory role in the synthesis of these phenolic substances. The variation in PAL activity during illumination does not follow the same course as described for other plants.  相似文献   

16.
R. Tevissen 《PSN》2008,6(1):38-53
This article questions the epistemic relationships of causal indeterminism in de Clérambault’s automatisme mental and Janet’s psychological automatism, including the concept of chance (tychè & automaton) as it evolved from Aristotlés Physics to the works of Cournot in the 19th century. De Clérambault conceived mental automatism as a causal anideism, enabling him to regard the self-organized morphogenesis of hallucinatory psychotic delusions from initial conditions, which express the apparent properties of fortuity, arbitrariness, and contingency. Janet refutes the postulate of the anideism of mental automatism in favour of a disorder in the regulation of action caused by specific feelings, and Ey envisions an accident in a hypothetical body plan based on a teleological explanation that is organ-based but not mechanical. These doctrines, however, support an objectivistic and naturalistic point of view regarding the apparent indeterminism of the thought automaton. They must not ignore the subject’s intrinsic perspective, which operates on the order of the tyché and makes it possible to analyze mental automatism, such as the subject’s refusal to recognize the possibility that a part of contingency and intentional indeterminism can emerge spontaneously in the course of thought and its inner language, and that this spontaneity could be the result of an unconscious choice.  相似文献   

17.
A rise in temperature as well as the passage from dark to light increases the cardiac beat of adult Locusta migratoria. Continuous exposure to light considerably decreases the sensibility to temperature variations. Neither the corpora allata nor the corpora cardiaca have any influence in this case.  相似文献   

18.
19.
The lowest part of the Postolonnec Formation (western Brittany) can be assigned to the middle Arenig Didymograptus nitidus Zone on graptolite evidence. Preliminary information on the Chitinozoa agrees with this age assignment, which defines more precisely the age of the underlying Grès armoricain Formation and also demands reconsideration of the problems associated with early Ordovician palaeogeography and sedimentology in the Massif armoricain.  相似文献   

20.
This paper presents for the first time the inventory of the Paleocene and Lower Eocene foraminifers located in the North Pyrenean trough, between the Atlantic Ocean and the neighbourhood of the town Pau. They have been studied from three outcrops. The Bidart Beach section shows the Lasseube Formation from the Cretaceous/Paleogene boundary to the base of the P 3a zone. The Loubieng Quarry section, near Orthez, represents the upper P 3a zone and the lower P 3b zone as well as the Lasseube Formation / Pont Labau Formation boundary. The interval between the upper part of the P 3b zone and the upperest part of the P 5 zone crops out along the Gan - Rébénacq road with a hiatus located at the Paleocene / Eocene boundary, the whole interval belonging to the Pont Labau Formation. 394 taxons of foraminifers are present in this formations: 349 benthic and 45 planktonic species. The Velasco type benthic foraminifers show a middle bathyal depositional environment, with a paleobathymetry included between 500-600 m and 1000 m: Nuttallides truempyi, Osangularia velascoensis, Bulimina trinitatensis. The Midway type species which were transported by the turbidite currents from the lower to middle neritic environments are frequent as well as the Cretaceous reworked species. The species number is low: 29 in the iridium layer of the Cretaceous/Paleogene boundary (P 0 zone). Fauna grows rich quickly in the Pα zone reaching 129 species. The diversity grows up progressively from P α to the P 4a zone (NP 8). The disappearances are rare until his horizon, but their number is bigger than the number of appearances from the P 4b zone. It reaches their maximum between the P 4c zone and the P 5 zone. It shows that the decline of the Paleocene fauna begins around 2 million years before the thermal event of the Paleocene / Eocene boundary in the Aquitaine sections. The disappearances stay important in the Lower Eocene - Ypresian, but the appearance of lots of Eocene species show that the fauna renewal is located in this stage. The Cretaceous taxa dominate in the Paleocene benthonic fauna. The appearance or the disappearance of some species has a stratigraphic value in the Aquitaine region: the disappearance of Coryphostoma incrassata in the P 1b zone, the appearances of Plectina dalmatina, Elongobula grata (P α); Bulimina tuxpamensis (P 2); Tritaxilina cubensis, Thalmannita madrugaensis (P 3a); Svenia bulbosa (P 3b); Discorbis perovalis (P 4a/NP 7); Elongobula pulchra, E. pupa, Asterigerina bartoniana, Neorotalia gr. tuberculata (P 4a/NP 8); Bigenerina pannonica, Pentellina pseudosaxorum (P 5/NP 9-10).  相似文献   

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