首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 0 毫秒
1.
2.
Sans résuméLa Pointe-du-Lac, P. Q.  相似文献   

3.
Summary In this brief work, authors study the five Chalcidids parasites of the olivefly in the mediterranean zone and discuss the systematic point of view. They modify the generic name (Cyrtoptyx, Pnigalio) and show the existence of the new speciesP. mediterraneus; this name substitutes the other nameE. longulus Zett which was wrongly given to theDacus's parasite. A table has been done for the rapid identification of the five species of Chalcidids.
Riassunto Nel presente breve lavoro, gli AA. riprendono lo studio dei cinque Calcididi parassiti della mosca delle olive nella zona mediterranea, ne discutono il valore dal punto di vista sistematico, ne modificano la denominazione generica (Cyrtoptyx, Pnigalio) e mettono in evidenza l'esistenza della nuova specieP. mediterraneus, il cui nome sostituisce quello diE. longulus Zett., erroneamente attribuito al parassita delDacus. E'stata compilata una tabella per l'identificazione rapida di queste cinque specie di Calcididi.
  相似文献   

4.
Sans résuméStagiaire de Recherches au Centre de Recherches Hydrobiologiques du C.N.R.S.  相似文献   

5.
6.
Résumé En cours de cette etude ont été énoncées les données concernant la manifestation de tufs zoogènes dans les eaux qui ravitaillent les lacs de Plitvice en Yougoslavie. Outre le tuf chironomide qu'on y trouve représenté sous trois types: oocardien, cratoneuronien et platyhypnidien, il a été établi qu'à l'endroit où se rencontrent la Crna rijeka et Bijela rijeka, on rencontre un type particulier de tuf trichoptere. Ce tuf se forme par l'action du trichoptère Stenophylax et Rhyacophila, ainsi que par l'action du gastropode Lithoglyphus fluminensis. Par leurs gangues et leurs coquilles, ils maintiennent les parcelles de calcaire sécrétées par voie abiogène. Ainsi se forme un substrat calcareux sur lequel viennent se poser ensuite des cyanoficées et des desmidiacées ∘ocardium stratum qui forwent can tuf de caractère lacustre. Quoiqu'à l'origine ces tufs soient différents, ils forwent can tout. Un peu plus bas dans la rivière, se forme can tuf semblable avec cette seule différence que son substrat est formé aussi de tufs cyanoficées et oocardiens, car ici la seule base solide est formée par des branches et des troncs. Nous signalons pour finir que le reste du tuf en cet endroit n'est pas conditionné seulement par des facteurs biogènes simples, mais que vraisemblablement d'autres composants agissent dans lesquels notamment des animaux jouent can r?le.
Zusammenfassung In dieser Verhandlung haben die Autoren besondere Angaben über das Vorkommen des zoogenen Tuffes im Gebiete der Verpflegungsgew?sser von Plitvička jezera in Jugoslawien mitgeteilt. Nebst dem Chironomidentuff, welcher hier in drei verschiedenen Formen, als Ookardischer-, Kratoneuronischer- und Platyhypnidischer Chironomidentuff vorkommt, wurde festgestellt, dass in den Verbindungsgebieten der Flüsse Crna rijeka und Bijela rijeka, noch eine besondere Form des Tuffes, sogenanter Trichopterentuff erscheint. Diese Form des Tuffes kommt durch die Mitwirkung der Larven von K?cher-fliegen Stenophylax and Rhyacophila und Schnecken Lithoglyphus fluminensis zustande. Kalkteilchen werden von ihren K?chern und Geh?usen zurückgehalten, und auf diese Weise durch einen abiogenen Vorgang ausgeschieden. Auf dieser so entstandenen Kalkunterlage siedeln sich nachdem Cyanophyceen, und von den Desmidiaceen Oocardium stratum an. Dieser Tuff hat einen durchwegs lakustrischen Charakter. Obwohl die genannten Tuffe ihrer Entstehung nach verschieden sind, stellen she doch eine einheitliche Erscheinung. In etwas abw?rts gelegener Richtung entsteht eine ?hnliche Form des Tuffes, nur wit dem Unterschied, dass der Untergrund hier auch als Oocardium-und Spaltalgen-Tuff ausgebaut ist, da in diesen Falle die einzige feste Unterlage von Zweigen und Balken gebildet wird. Endlich wurde noch darauf hingewiesen, dass auch aller übrige Tuff in diesem Gebiete nicht nur von biogenen Faktoren abh?ngt, sondern dass wahrscheinlich noch andere Vorg?nge bei seiner Bildung beteiligt sind. Dabei kommt auch den Tieren ein gewisser Anteil zu.
  相似文献   

7.
8.
9.
10.
11.
12.
Résumé Les modalités de la détermination et de la différenciation du dimorphisme sexuel de Néréidiens (Annélides Polychètes) ont été recherchées chezNereis pelagica L. etPerinereis cultrifera G. par des expériences de décérébration, de castration (par irradiation X), de greffes et d'injection de produits génitaux.Les caractères sexuels somatiques des cirres parapodiaux (renflement et crénelures) se développent toujours conformément au sexe génétique quel que soit l'état génital de laNereis et la nature de l'intervention. La détermination des caractères sexuels somatiques des cirres parapodiaux apparaît donc comme étant très précoce (3 mois au moins avant la différenciation génitale) et stable.Par contre, les papilles pygidiales, caractère sexuel mâle dans les conditions normales, peuvent se différencier chez les très jeunes femelles dont l'épitoquie est déclenchée prématurément par décérébration et chez les femelles de tout âge dont les transformations hétéronéréidiennes sont réalisées en présence d'un milieu mâle (injection de produits génitaux, greffe sur un mâle). Les papilles pygidiales semblent donc déterminées précocement chez les deux sexes; leur différenciation est cependant inhibée chez les femelles au cours de la maturation génitale.
Control of determination and the differentiation of the sexual somatic characters of Nereids (Annelida Polychaeta)
Summary The modalities of determination and differentiation of sexual dimorphism of Nereids (Annelida Polychaeta) were investigated inNereis pelagica L. andPerinereis cultrifera G. with experiments involving decerebration, castration (by X irradiation), grafts or injection of genital products.The sexual somatic characters of the parapodial cirri (swelling and crenellations) always develop according to the genetic sex, whatever the genital state of the Nereis and the nature of the intervention. Therefore the determination of the sexual somatic characters of the parapodial cirri appear to be determined in a very precocious and stable way (at least 3 months before the genital differentiation).The pygidial papillae, a male sexual character in normal conditions, can be formed by very young females in which heteronereidation is realized prematurely by decerebration, and by females of any age in which heteronereid transformations are realized in a male environment (e.g. by injection of genital products, or grafting onto a male). Therefore the pygidial papillae may be determined precociously in either sex; however their differentiation is normally inhibited in females in the course of genital maturation.
  相似文献   

13.
First data about Halictidae (Hymenoptera: Apoidea) in the región of Batna (Eastern Algeria) Investigations carried out on Halictidae bees in different localities in the region of Batna during the spring and summer seasons of 2009 and 2012 allowed the identification of 35 species; Lasioglossum musculum is reported for the first time in Algeria. The presence of Sphecodes puncticeps Thomson, 1870, a cleptoparasitic species, is confirmed. The flowers visited and the flight period of each species are noted.  相似文献   

14.
The different types of recrystallization which can be observed in the Triassic involutinids should be considered in the taxonomic treatment of this foraminiferal family. If the diagenetic modifications of the test are neglected the same form could be placed into different suborders. Our inclusion of the genusTriasina Majzon in the Involutinidae proposed earlier on purely morphologic grounds, seems to be supported by the fact that the same types of recrystallization exist inTrocholina, Involutina undTriasina.  相似文献   

15.
Bernard Crochet 《Geobios》1977,10(5):723-739
Limestone beds included in the «Poudingue dePalassou around Sabarat (Ariège) contain a Gasteropod fauna known since J.-B. Noulet's works (1857). The systematic inventory of the different localities and the paleontological study of the material collected prove that two successive and clearly different Mollusc faunas existed. The bartonian fauna with Ischurostoma formosum minutum (Noulet) and Biomphalaria vasseuri (Roman) is preceded by a lower lutetian fauna with Biomphalaria pseudoammonius (Scholtheim): in the latter, two paleoecological groups are opposed according to the sheltered channels of two kinds in which limestones beds have been built. Besides, the chronostratigraphic consequences imply that the middle part of the «Poudingue de Palassou has been formed from Lower Lutetian to Bartonian.  相似文献   

16.
17.
18.
《L'Anthropologie》2023,127(1):103092
Flint was the most widely used lithic raw material in Europe in Prehistory and, more specifically, was a fundamental resource in the economic and social networks of hunter-gatherer groups in the Cantabrian Spain during the Upper Palaeolithic. The undeniable preference for it compared with other resources was due to a series of factors, such as its easy availability because of its abundance and wide distribution of outcrops, and its excellent qualities for knapping. This summary of the available information about flint and other raw materials used by hunter-gatherers is framed in the context of Upper Palaeolithic occupations in Cantabrian Spain. First, it presents the studies focusing on the provenance of the different types of flint that are found in those occupations; their quantitative representation at each of the sites; their preference, if that is the case, over other raw materials; and the model of their diffusion across the territory. Then other resources are considered, such as quartzite, ochre and different metamorphic, sedimentary and igneous rocks, as well as some materials of biological origin, such as amber, jet/lignite and fossils of animal origin. However, the information available about the use of the latter raw materials in Cantabrian Spain during the Upper Palaeolithic is quite limited and studies of their characterisation are very recent.  相似文献   

19.
V. Delucchi 《BioControl》1961,6(2):109-113
Summary The author proposes to standardize the preparation technique for microhymenoptera. The insects have to be presented for identification in a dry state, mounted on a minute pin or glued on a heavy paper point (double-mounting). Preference is given to the mounting on minute pin, as this method has the advantage that a specimen pinned with a minuten may be removed from its support and each morphological detail easily observed. The minuten is fixed to a short strip of soft material such as polyporus (bracket fungus); if this is not available, stiff paper may be used. The support with the pinned specimen is then attached to a pin no. 3 (fig. 1–3). The absence of glue is advantageous, especially in subtropical countries, where the glue is generally destroyed by bacteria and fungi. When the pins are unavailable for this double-mounting technique, the author proposes to glue the thoracic pleurae of the insect to the previously folded tip of a heavy paper point (fig. 6). The material for identification may be preserved in a liquid medium (as alcohol with some drops of glycerine) after a series of individuals have been prepared according to the double-mounting technique. Also, specimens in excess may be sent dry in a plastic or glass tube between two cellucotton masses.   相似文献   

20.
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号