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1.
Jean Roman 《Geobios》1977,10(3):337-349
Echinolampas is a subtropical genus living in rather shallow water; one may regards it as a climatic marker. The theory of continental drift affords a rather good explanation for its distribution in space during Cenozoic era. It appears in Old Wolrd during Paleocene and it occurs in Central America during Middle Eocene; that implies it had to cross the already broad Atlantic Ocean; but at that time this ocean is not as broad at it is now. Migration along the shelf area which rimmed North Atlantic might have been impossible, owing to disruption of land connection between Europe and North America. Probably the migration occured in low latitudes and pelagic larvae were transported by one of the two equatorial currents. Diversity of the genus has much decreased during Late Eocene. The cause may be chiefly due to climatic deterioration, resulting from marine communication between North Atlantic and Arctic Ocean. Echinolampas occurs for the first time in Australia during Oligocene. One may suggest the possibility of a link between this late evidence and the quite remote position till then of Australian continent. During Miocene, the relative decrease in Echinolampas diversity in the Mediterranean Basin occurs as a result of the welding between Asia and Africa.  相似文献   

2.
Five alkaloids have been isolated from Alstonia vitiensis: pleïocarpamine, vincorine, cabucraline, alstovine (11-methoxycompactinervine) and quaternoxine; the latter two are new alkaloids.  相似文献   

3.
M. Laurain 《Geobios》1980,13(1):21-43
The assemblages of Crassostrea gryphoïdes of the Loupian's quarry is constitued of differents morphotypes which result of ecological effects (population density, locality and position in the assemblage). The selection of individuals with her life position shows two lots of Ostreidae the morphology of which is statistically different. The observations about Crassostrea of outcrops of Rhone's Valley and Touraine confirm the relations between position (liable to population's density) and morphology. The two types which are point out are often recognize as different species describe by E.F. von Schlotheim, 1813: Crassostrea gryphoïdes and Crassostrea gingensis. Therefore this two species must be consider as synonymous.  相似文献   

4.
The recent Rhinoceros sondaicusDesmarest of 0815 Indochina are referable to a separate subspecies Rh. sondaicus annamiticusHeude. Following a comparison with the various other subspecies, a diagnosis is established on the base of craniological, odontological and osteological features. Rh. sondaicus annamiticus is descended from the Pleistocene form from Indochina, Rh. sondaicus guthi; the distinctive geographic features being superimposed on the species-wide evolutionary trends.  相似文献   

5.
In Mesogea, the Harpoceratinae were known asearly as the end of the Lower Carixian. They later reached the sub-boreal province through the Alps or the South of the Iberic Peninsula. The analysis of the populations met in four crosssections of the Lower Domerian (Causses, Mâconnais, Franche-Comté, Portugal) showed the settling down of the Protogrammoceras isseli group that set up and evoluated in a similar way in the different areas in spite of a certain originality.On the one hand, it gave the cladogenetic groupP. monestieri-nitescens by diminution of the ribing density, strengthening of the ribs and simplification of the suture.On the other hand, a slower evolution give, near the end of the Stokesi zone, P. normanianum in the Paris Basin and in Burgundy, and P. lusitanicum in Portugal. At the same time, a new invader, P. celebratum, arrived in the Causses (and in Portugal).  相似文献   

6.
Ammonites diartianus d'Orbigny is a Vascocerasoof late Cenomanian (Sciponoceras gracile Zone) age, occuring in both Sarthe (France) and southern England. It is the earliest vascoceratid known from France, and its recognition is of great significance, lending support to recent suggestions that the classic Vascoceras gamai - mundaeChoffat group are of Upper Cenomanian age.  相似文献   

7.
8.
J. Rey  M. Bilotte  B. Peybernes 《Geobios》1977,10(3):369-393
The marine Albain from Estremadura is splited up into four Orbitolinidae zones, adjusted to biostratigraphic scales from mesogean province: zone with Orbitolina (Mesorbitolina) minuta (lower to middle Albian); zone with Neorbitolinopsis conulus (base of upper Albian); zone with Orbitolina (Orbitolina) concava (top of upper Albian) and zone with Orbitolina (Orbitolina) duranddelgai (Vraconian). The vertical extension of the main fossils is replaced in the framework of these zones. The most interesting species for biostratigraphy, paleoecology or taxinomy are summarily described.  相似文献   

9.
The increase of infections due to non-Candida albicans species made it very necessary to conduct adequate characterization to be able to identify the species of Candida isolated from traditional fermented foods. In this study, based on their hue on Candida Chromogenic Agar medium, a total of 136 yeast strains were isolated from tchapalo and bangui. Molecular identification based on PCR-RFLP of internal transcribed spacers of rDNA (ITS) and sequencing of the ITS and the D1/D2 regions allowed us to assign these isolates to seven species: Candida tropicalis, Candida inconspicua, Candida rugosa, Saccharomyces cerevisiae, Kluyveromyces marxianus, Hanseniaspora guilliermondii, Trichosporon asahii. With the respect to each beverage, six species were found among with four species are regarded as opportunistic pathogens. From these, C. tropicalis, C. inconspicua and K. marxianus were the most commonly encountered. The enzyme activities of the potential pathogens assessed using API ZYM system showed that almost strains had esterase, esterase lipase, valine and cystine arylamidase, alpha chymotrypsin, alkaline phosphatase and naphthol phosphohydrolase activities. The activity of α-glucosidase was found only in C. tropicalis and C. inconspicua strains isolated from tchapalo while β-glucosidase activity was found in all strains from tchapalo and only in C. inconspicua isolated from bangui.  相似文献   

10.
Besides quercetin, kaempferol and isorhamnetin, at least three other flavonoids can be obtained from the leaves of Hymenosporum flavum after acid hydrolysis. One of these, a kaempferol derivative: p-hydroxyphenyl,(3,4′,5,7 -tetrahydroxy)-8-flavonyl, methylmethane or 8-α-methyl-C-(p-hydroxybenzyl)kaempferol has been identified by study of its spectral properties. It is probably an artifact formed during hydrochloric acid treatment of the leaves.  相似文献   

11.
Latex lutoids constitute a polydispersed vacuole with lysosomal character. Lutoids possess a membrane which retains ATP-ase and acid phosphatase activity. Acid phosphatase may be inhibited by ammonium molybdate or phosphate, making it possible to characterize an ATP-ase with an optimum pH of between 7·5 and 8·0. This ATP-ase is Mg2+ dependent, does not require K+ specifically but is affected by the ionic concentration of the medium.  相似文献   

12.
The changing patterns of haemolymph proteins were followed in male and female adults of normal and parasitized Anacridium aegyptium during diapause (autumn, winter) or during activity (spring) of their endocrine system without or with electrostimulations of the pars intercerebralis (PI).The haemolymph protein concentration is high in winter and decreases in spring. It is comparatively depleted in locusts infected by the fly Metacemyia calloti. However, the depletion is significant only in ‘castrated’ females.Fifteen protein fractions were resolved by polyacrylamide disk gel electrophoresis in haemolymph of normal and infected locusts during diapause and activity. Some fractions decrease in quantity during activity in males, normal females, and parasitized females with complete ovarian development. One fraction disappears in females with mature eggs and seems correlated with formation of the eggshell. Eight others protein fractions exhibit electrophoretic mobility identical to the 7 protein fractions of homogenates of eggs. There is little doubt that these haemolymph protein fractions are involved in yolk synthesis and are thus ‘vitellogenic’. One of these ‘vitellogenic’ fractions (band 6) is larger in yolk than in blood.Five protein fractions were demonstrated by electrophoresis of homogenates of parasites. Their electrophoretic mobilities are similar to those of 5 of the 8 haemolymph ‘vitellogenic’ fractions of the host. There is little doubt that these 5 haemolymph protein fractions (one of them is the band 6) are involved in the nutritional requirements of the parasite.Electrostimulation of the PI, during diapause and activity, increase the haemolymph protein concentration and chiefly the protein concentration of the blood band 6. Thus, the median neurosecretory cells of the brain (M-NSC) regulate protein synthesis and chiefly the synthesis of ‘vitellogenic’ proteins.In parasitized females, the increase of the haemolymph protein concentration after electrostimulations of the PI is associated with an enhancement of ovarian development. The depletion of the haemolymph protein concentration in ‘castrated’ females is thus involved in the inability of the oöcytes to sequester available proteins from the haemolymph. The haemolymph protein deficiency may be attributed to (1) an impairment of protein synthesis, attendant upon the hypoactivity of the M-NSC, and (2) the nutritional requirements of the parasite.  相似文献   

13.
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15.
Véra Eisenmann 《Geobios》1975,8(2):125-IN14
The fauna yielded by the Nihowan lower pleistocene lacustrine deposits includes two species of Equus beside one Hipparion. Equus sanmeniensis was described in 1930 by Teilhard de Chardin and Piveteau; this species is characterized by its large size and the presence of cups on all incisors. Equus teilhardi nov. sp. is smaller and its lower incisors are devoid of cups. It is the first time that such an absence is noted among eurasiatic Equus; till now only some californian, south-american and african species were known to have lowers incisors without cups. The finding of several Equids in the same deposits and the significance of the lack of cups are briefly discussed.  相似文献   

16.
17.
The discovery in rocks of Middle Devonian age of a new Asteropyginae, Kayserops? cantarmoricus n. sp., common to both Central Armorican Syncline (Rade de Brest, France) and the south flank of the Cantabrian Mountains (Spain), suggests a geographical connection, perhaps temporary, between these two regions. The particular morphological characteristics of this species shed new light on present knowledge of the sub-family Asteropyginae.  相似文献   

18.
19.
A lot of Stringocephalidae have been discovered,for the first time, in the Givetian of Afghanistan. Among these we have identified: Stringocephalus aff. burtini (Defrance)), St. (Parastringocephalus) dewalense n. sp., Rensselandia aff. circularis (Holzapfel)). The locality is situated in Hazarajat, in a Devonian sequence which is more than one thousand meters thick and the age of which ranges from Gedinnian (probable) to Frasnian.  相似文献   

20.
Bernard Courtinat 《Geobios》1980,13(2):209-229
Palynological inventory of Saint-Fromont pit 0815 (Manche, France) related to Hettangian seems to show the conspecificity of Classopollis chateaunoviReyre, 1970, Classopollis kieseriReyre, 1970 and Classopollis harisiiMuir & Van Konijnenburg-Van Cittert, 1970. SEM pictures exibit some sculptural elements interpreted as structural attachments of grains in tetrad and compared to those of genus DicheiropollisTrevisan, 1971.  相似文献   

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