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1.
Effects of 2-chloroethylphosphonic acid on the latex of Hevea brasiliensis were studied during 7 days after its application on the tapping panel of the tree. Ribosome polymerisation shows a dramatic rise within 12 hr after treatment. This shift is overcome at first without rRNA synthesis. Increase of latex production and latex pH exhibit similar features and start 24 hr after application of the, stimulant. After 4 days, rRNA concentration and the stability of the lutoïds (microvacuoles with lysosomal characteristics) change significantly.  相似文献   

2.
Michel Jaffrezo 《Geobios》1973,6(1):71-IN23
Bibliographical, geographical and stratigraphical index of all Algae Dasycladaceae describedin Jurassic and Lower Cretaceous from the world.  相似文献   

3.
Only one piece of liassic ammonite is known in Corsica (SE of St. Florent in the “unité of Tuda”). It is a Arietitidae, probably Paltechioceras or Vermiceras (top or bottom of Sinemurian). The Lias of Tuda, similar to that of “écailles de Corté”, belongs to parautochtonous external realm.  相似文献   

4.
Mireille Gaudant 《Geobios》1978,11(2):189-210
The genus PateropercaWoodward which includes two species, P. libanicaWoodward and P. robusta nov., is described in detail on the basis of acid prepared material from the Cenomanian fish bed of Hadjula (Lebanon). It is demonstrated that Pateroperca does not belong to the Order Ctenothrissiformes contrary to the generally accepted idea. Despite the possession of characters known among Acanthoterygian fishes, it is not possible to show that this genus may be related to the Order Beryciformes and the new family Pateropercidae nov. is left as Ctenosquamata incertae sedis.  相似文献   

5.
It has been shown previously that 16-14C palmitic acid, 1-14C cetyl alcohol and 16,17-14C dotriacontane dissolved in sea water are rapidly incorporated into the oyster Ostrea gryphea L. and the sea anemone Calliactis parasitica Couch. In the present communication, we establish that palmitic acid and cetyl alcohol are slowly metabolized, but the hydrocarbon dotriacontane is unchanged after 48 h. The results are discussed.  相似文献   

6.
Jean-Paul Colin 《Geobios》1974,7(1):19-xxi
Sixteen species of ostracods are described from upper Cenomanien, Turonian and Campanian of Dordogne (region of Saint-Cyprien). Thirteen of them are new and belong to genera Cytherella, Dolocythere, Hazelina?, Cythereis, Platycythereis, Quasihermanites, Kikliocythere, Netrocytheridea, Annosacythere, Neocythere (Physocythere), Amphicytherura. The three others belong to the genera Platella?, Paracypris and Hemicytherura? are left in open nomenclature.  相似文献   

7.
Most of the Tethyan species usually attributed to the genera Platypleuroceras, Uptonia and Dayiceras (Polymorphitidae) are in reality forms phylogenetically related to Metaderoceras, but which show convergence in their morphology. Their originality justifies the creation of a new genus, Dubariceras and two new species, D. dubari and D. freboldi.The palaeobiogeographic implications of this phylogenetic interpretation confirm the profound differences between Tethyan and Boreal faunas in the Carixian. The platycone Polymorphitidae (Platypleuroceras, Uptonia and Dayiceras) are almost completely restricted to the Boreal Realm, whereas the faunas of the Tethyan Realm largely comprise the Acanthopleuroceratidae (Tropidoceras), Metaderoceras and its allied genus Dubariceras.  相似文献   

8.
J Thierry 《Geobios》2003,36(1):93-126
The ammonite fauna of the outcropping Bathonian-Callovian of the Boulonnais (Northern France) is described in detail for the first time. In the middle and Late Bathonian, the fauna is very restricted, reduced to some Perisphinctidae (Procerites) and Clydoniceratidae (Clydoniceras, Delecticeras). The abundance and the biodiversity of assemblages increase during the Callovian. These faunas are typically Subboreal, marked by Gowericeratinae (Kepplerites, Sigaloceras), Kosmoceratinae (Kosmoceras) and Proplanulitinae (Proplanulites), associated with Boreal taxa such as Cadoceratinae (Cadoceras) and Cardioceratidae (Quenstedtoceras), and Submediterranean taxa, Pseudoperisphinctinae (Homoeoplanulites, Poculisphinctes), Peltoceratinae (Pseudopeltoceras) and Macrocephalitinae (Macrocephalites). Representing the only Jurassic onshore outcrops, between the English and Normandy coasts, and the Ardennes area, the interest of these faunas for correlations between the Western and Eastern European (Russian) platforms is emphasized. Palaeobiogeographically, particularly concerning the southward migration/dispersion of the Boreal taxa, the role played by the transgressions/regressions and the resulting paleobathymetric and palaeoclimatic implications is discussed.  相似文献   

9.
A detailed investigation of the Bajocian-Bathonian protoglobigerinids and other globigerina-like foraminifera of the Southern Jura Mountains reveals an unsuspected diversity, with seven species of Conoglobigerinidae and two species of Oberhauserellidae. The discovery of two umbilical apertures in Oberhauserella as well as in some Conoglobigerina questions the generic taxonomy and raises the problem of comparisons with literature. For these reasons, five new species have been proposed: Oberhauserellaparocula and O. aff. parocula (with two apertures), “Conoglobigerina”trilocula and “C”.biapertura (with two apertures), C.solaperta and C.pupa. We demonstrate that Globuligerinabalakhmatovae (Morozova, 1961) (here emended) has a small globuligerine aperture as well as G. aff. dagestanica (Morozova, 1961). Despite the different taxonomic concepts, the Southern Jura Mountains associations, that are typical of the epicontinental platform, most closely match those of the Dagestan in the Caucasus. They clearly differ from those of the oceanic Tethys.  相似文献   

10.
A new species of DionideBarrande, Dionide mareki nov. sp., is described from siltstones of Llandeilo age in the Armorican Massif and north Portugal. The known geographical distribution of this species presents new evidence for the strong palaeobiogeographical relationship, during the Llandeilo, between the Valongo district (near Porto) and the Martigné-Ferchaud and Saint-Julien-de-Vouvantes synclinoriums south of Rennes.  相似文献   

11.
A stratigraphical chart of marine ostracoda from Lower Miocene to Recent is established. Selected species (approximatively 220) are those morphologicaly well characterized and known from different parts of the Mediterranean area. It appears that: • lower Miocene ostracodes are still poorly known; • specific diversity is high during the Tortonian and the Lower Messinian before the complete disappearance of marine Mediterranean species during the Upper Messinian évaporitic episodes; • during the early Pliocene, about half of the Upper Miocene marine species are reintroduced with the Atlantic waters; other species migrate for the first time in the Mediterranean Sea by the same way; • at the end of the Pliocene or at the beginning of the Pleistocene several species known in Mediterranean since the Middle Miocene or before, such as Cytherella sp. gr. transversa and Ruggieria tetraptera, as well some “nordic guests” such as Hemicythere villosa and Cythere lutea, appear. This work is an opportunity to confirme a Late Miocene age for the Neogene of Skyros (Aegean Sea), to assign the “Upper Pliocene” of Terquem to the Lower Pleistocene and to refute the existence of a pliocene psychrosphere.  相似文献   

12.
Gyrogonites of charophytes from two localities of the Oudiksou syncline (Middle Atlas, Morocco) are studied. The Irbzer formation in the Achlouj-2 site yielded charophytes (Feistiella oblonga, F. globosa, Strobilochara apiculata, S. diademata) that suggest a Campanian-Maastrichtian age; this result is consistent with all previously published biochronological studies. The overlying Bekrit-Timahdit formation, supposed to be Thanetian to Lutetian in age, without paleontological evidence, yielded charophytes in the Saf locality (Peckichara cf. llobregatensis, Feistiella sp. 1, Maedleriella sp.). This association indicates a Paleocene age for the middle member of this formation.  相似文献   

13.
Twelve species of the family Cyprididae were found in the Upper Miocene of the Turiec Basin, of which three are new - Herpetocypris denticulata nov. sp., H. pusilla nov. sp. et Psychrodromus janzi nov. sp. The occurrence of Mediocypris suggests that ostracods occupied the Turiec Basin since the Middle Miocene. The psychrophilic genera (Psychrodromus and Cavernocypris) provide evidence of cold springs around the lake. In the sediments studied, the Cyprididae are associated with other ostracods that characterise shallow aquatic habitats and a diverse community of both aquatic and terrestrial plants. The sexual paleo-populations of Heterocypris salina (Brady, 1868), Herpetocypris pusilla nov. sp. and Psychrodromus janzi nov. sp. are observed.  相似文献   

14.
Cultures of Nocardia restricta, a prokaryote from the group of Actinomycetes, can be synchronised by diluting, in a fresh growth medium, cells already in stationary phase. The synchronisation of the cultures is monitored by examining the synchrony of DNA replication.In these synchronised cultures, the intracellular cyclic AMP level exhibits rythmic oscillations with a period equal to the generation time of the culture. There is only one peak per generation. The average ratio of maximum to minimum concentrations is at least 3.Cyclic AMP accumulates also in the medium with a step pattern. It appears in the medium during maximum production of cyclic AMP in the cell.The specific activity of adenylate cyclase (EC 4.6.1.1) measured in the 30 000 × g pellet of cell-free extracts also oscillates and correlates well with fluctuations in the cyclic AMP level. At the end of exponential growth, cyclic-AMP phosphodiesterase (EC 3.1.4.17) is detectable in the cells. The specific activity of this enzyme measured in the 30 000 × g supernatant of cell-free extracts shows also an oscillating pattern.To our knowledge it is the first time that such oscillations in the metabolism of cyclic AMP are described among prokaryotes. It is now possible to look at a link between this phenomenon and the cell cycle of the organism.  相似文献   

15.
Found in Chiapas (South-East of Mexico), Praealveolina michaudi nov. sp. and Chubbina jamaicensis (of Campanian-Maestrichtian age) are described, both evolved from Nummoloculina sp. while Raadshoovenia guatemalensis (upper Paleocene-lower Eocene) arises from Quinqueloculina. We precisely analyze and modelize the nepionic coiling during the evolutionary change from Miliolacea to Alveolinacea. During ontogenesis as well as during phylogenesis, quinqueloculine coiling progresses to streptospiral and then to planispiral chamber arrangement with the increase of volume of embryo and of chambers. Appearance of these large foraminifers are understood as a consequence of the rise of K-strategies in their mode of life, following the development of photosynthetic symbioses.  相似文献   

16.
The paleontological analysis of the fauna from three Late Pleistocene localities in Southern Caucasus (Saka?hia, Ortvala, and Bronze cave) confirmed the presence of Ursus spelaeus, Canis lupus, Equus ferus, Rhinocerotidae, Cervus elaphus, Capreolus capreolus, Alces alces, Bison priscus, Capra caucasica, Ovis ammon and Sus scrofa. The study also permitted the identification of new taxa for these localities. There may be the presence of reindeer (Rangifer tarandus) at Saka?hia, however it has not yet been confirmed. Moreover, remains of aurochs (Bos primigenius) were identified, in particular at Bronze cave where its abundance is exceptional. Indeed, Bos and Bison are generally very rare in Southern Caucasus. The analysis of the proportion of the different species in each locality revealed the two types of occupations of the caves, one dominated by hominids and the other by carnivores. At Saka?hia, where fauna is dominated by the presence of cave bear, the cave was seasonally occupied by Neanderthal groups. On the other hand, Bronze cave corresponds to a habitat of hunters, which occupied the site for longer periods.  相似文献   

17.
When grown on a synthetic medium containing Zn2+ and Cd2+ in toxic concentrations and a high concentration of Mg2+, the mycelium of Aspergillus niger ATCC 9029 is pigmented yellow. Four pigments have been chromatographically separated. Two are still unknown; the others are asperenone and asperrubrol. Asperrubrol is the methyl ester of a dimethyl 13-phenyl-3-ol-2,4,6,8,10,12-tridecahexaenoic acid. One of the methyl groups is on C2 and the other is probably at C8. Asperrubrol has been obtained as the enol of the all trans molecule; ketoe nolisation can be obtained by action of heat or alkalis. When grown on the same medium, 13 of 17 strains of A. niger produced asperrubrol and asperenone.  相似文献   

18.
C. Arambourg has described a new genus and a new species of a cercopithecid Anomalopithecus bicuspidatus (1), from the Ain Brimba Villafranchian site (Tunisia). This form is based on heterogeneous material: the species holotype is an upper incisor of Hyaena striata praecursor ARAMBOURG (1), meanwhile the syntypes (M2 and M3) belong to Macaca sylvanus cf. sylvanus.  相似文献   

19.
Four flavonol glycosides, one flavone glycoside and six C-glyosylflavones have been identified in the leaves of Phragmites australis. Among the latter is 7,3′-dimethylisoorientin, which has only been reported once before in nature.  相似文献   

20.
Vertebrate remains and nummulites have been investigated from the Late Eocene—Early Oligocene transgressive sequence of the «Chaînes subalpines south of the lake Annecy. The sedimentary environments range from fluvio-lacustrine shales and conglomerates at the base to hemipelagic Globigerina shales at the top. The fluvio-lacustrine white marls contain mammals of the upper, probably terminal Ludian, with affinities to the assemblage of Saint-Capraise. The brackish Cerithium beds have furnished charophytes of the Bembridge zone. The nummulite limestones are not dated precisely, but isolated, probably redeposited nummulites from the base of the Globigerina shales are of terminal Eocene or basal Oligocene age. The Globigerina shales themselves belong to the Oligocene.  相似文献   

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