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1.
Michel Melou 《Geobios》1976,9(6):693-717
Three species of Orthida are described from the «Schistes de Postolonnec Formation. The distribution of Crozonorthis musculosa n. g., n. sp. allows to improve the correlations between the Iberic Peninsula and the Armorican massif and supply new arguments for a Llandeilian age to a part of the «Schistes de Postolonnec Formation.  相似文献   

2.
The females of Rhabdophaga saliciperda have in their somatic cells 8 chromosomes and the males 6. The type of sex determination is therefore: X1X1X2X2—♀; X1X2—♂. The cells of the germinal line have 46 chromosomes, but a variation of their number was observed. In the oogonia and spermatogonia the number of heterochromatic chromosomes may exceed the number of E chromosomes, i.e. 8. In the beginning of the growth stage of the oocytes an incorporation of somatic cells was observed. The nuclei of these somatic cells persist in the cytoplasm of the oocytes until the maturation divisions. The possibility of their participation in the reconstruction of the nucleus of the mature egg is envisaged. The metaphase of the I segmentation division has a complex character. During prophase of the first meiotic division the E chromosomes form 4 bunches of 6–8 chromosomes each. Some univalents may also be present. The 8 S chromosomes form 4 regular bivalents. The 4 groups of E chromosomes persist until metaphase I. During metaphase I a phenomenon of expulsion of the majority of E chromosomes from the metaphase spindle was observed. The 4 bivalents remain in the equatorial plain of the spindle with some E Chromosomes. After this expulsion 2 groups of chromosomes are formed. In connection with them 2 spindles develop. An irregular distribution of E chromosomes follows without their division. The bivalents are probably separated in regular manner. These 2 spindles correspond to the I maturation division. The II maturation division was not observed because of lack of respective stages.  相似文献   

3.
《Geobios》1988,21(4):515-521
The wall of Thamnoptychia consists of a granularmedian lamina flanked by thick margins of cupular microlamellae in which are inserted fibrous spines. Ramose Tabulate Corals, with a considerable peripheral microlamellar thickening, are here united in the family Thamnoptychiidae nov. This name substitutes Dendroporidae De Fromentel 1861, since Dendropora owns a microstructure which differs it from all other Tabulate Corals.  相似文献   

4.
《Geobios》1988,21(3):369-374
Two fossil Hispini: Dicladispa bes-konakensis n. sp. from Bes-Konak (Miocene, Anatolia, Turkey) and Dicladispa muratensis n. sp. from Murat (Reuverien, Cantal, France) are described.Those species seem to belong to the mediterraneangroup in that genus.  相似文献   

5.
6.
《Comptes Rendus Palevol》2002,1(7):573-585
Brachiopods from the White Chalk of Meudon (Upper Campanian), listed in the catalogue of dˈOrbigny collection, are presented following the revised classification. This is not without difficulty, due to the few specimens found and/or to the heterogeneity of sets listed under the same number and labelled with the same name. The Brachiopod fauna in the Belemnitella mucronata Zone is well represented, considering the Invertebrate fauna as a whole. Two representatives of Craniiformea and about ten species of Rhynchonelliformea, from several superfamilies shared by two orders, are critically described, considering the recent observations and the last works after dˈOrbigny.  相似文献   

7.
A new species of woody bamboo (Poaceae: Bambusoideae),Chusquea guirigayensis, is described and illustrated. This species is placed inChusquea sect.Swallenochloa (McClure) L. G. Clark because of its shrubby habit, short waxy internodes, intravaginal branching, and linearly arranged subsidiary buds/branches. In addition, we discuss related species, and describe the ecology and distribution of the new species. Separate keys based on sterile and fertile material of the Venezuelan species ofC. sect.Swallenochloa are provided.  相似文献   

8.
Résumé Heteroxynema (Cavioxyura) viscaciae n. sp., parasite du caecum et du gros intestin d'un rongeur caviomorphe d' Argentine, Lagidium viscacia boxi Thomas, est décrit. Cette nouvelle espèce est très proche de Heteroxynema (Cavioxyura) chiliensis Quentin, 1975, parasite d' Octodon degus (Molina) au Chili, dont elle se distingue essentiellement par ses mensurations et par la disposition de certaines papilles génitales des mâles. L'étude de cette nouvelle espèce montre l'existence: (i) au niveau des structures buccales d'un dimorphisme sexuel d'un type peu fréquent chez les Oxyuroidea; (ii) de quatre paires seulement de papilles génitales mâles voisinant avec des reliefs cuticulaires qui, dans d'autres espèces, ont peut-être été confondus avec des terminaisons nerveuses supplémentaires; (iii) d'un gubernaculum et d'un spicule, organes rarement observés chez les Heteroxynematidae, mais dont la présence dans d'autres espèces du groupe pourrait avoir été ignorée; (iv) au niveau de l'ovéjecteur, d'un sphincter particulièrement différencié et développé.
Heteroxynema (Cavioxyura) viscaciae n. sp., parasitic in the caecum and large intestine of Lagidium viscacia boxi Thomas, is described. The most closely related species is Heteroxynema (Cavioxyura) chiliensis Quentin, 1975, a parasite of Octodon degus (Molina) from Chile, from which the new species differs by its measurements and disposition of the male's genital papillae. Study of this new species shows the existence of: (i) a type of sexual dimorphism infrequent in the Oxyuroidea, at the level of the buccal structures; (ii) only four pairs of male genital papillae adjoining cuticular protuberances which in other species may have been confused with supplementary nerve endings; (iii) a gubernaculum and a spicule, structures infrequently observed in the Heteroxynematidae, and possibly overlooked or ignored in other species; (iv) a sphincter which is strongly differentiated and developed.

Resumen Se describe a Heteroxynema (Cavioxyura) viscaciae n. sp. paràsito del ciego intestino grueso del rodeor Lagidium viscacia boxi Thomas. Esta nueva especie se asemeja a Heteroxynema (Cavioxyura) chiliensis Quentin, 1975, paràsito de Octodon degus (Molina) de Chile de la cual se diferencie esencialmente por sus medidas y por la disposicion de las papilas genitales del macho. El estudio de esta nueva especie muestra la existencia de: (i) un tipo poco frecuente en los Oxyuroidea de dimorfismo sexual a nivel de las estructuras bucales; (ii) cuatro pares de papilas genitales en el macho ubicadas proximas a relieves cuticulares que en otras especies pueden haber sido confundidos con terminaciones nerviosas suplementarias; (iii) de un gubernàculo y una espicula, organos raramente observables en los Heteroxynematidae, pero cuya presencia en otras especies del grupo pudo haber sido ignorada; (iv) de un sphincter particularmente diferenciado y desarollado.
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9.
The bryophyte vegetation of the Almería Province (SE Spain) has been studied according to the Braun-Blanquet method. Twenty-nine communities have been recognized, of which four are aquatic (classes Montio-Cardaminetea Braun-Blanquet & Tiixen 1943 and Platyhypnidio-Fontinalietea antipyreticae Philippi 1956), five terricolous acidophilous (classes Ceratodonto-Polytrichetea piliferi Mohan 1978 and Dicranelletea heteromallae Mohan 1978), 15 terricolous basiphilous (class Barbuletea unguiculatae Mohan 1978), four saxicolous (classes Racomitrietea heterostichi Neumayr 1971, Grimmietea anodontis Hadac & Vondraček in Jezek & Vondraček 1962 and Neckeretea complanatae Marstaller 1986) and one epiphytic (class Frullanio-Leucodontetea sciuroidis Mohan 1978 emend. Marstaller 1985). Three associations have been described as new: Rhizomnio punctati-Fissidentetum taxifolii (meso-hygrophilous, sciophilous, terri-humicolous, edaphically indifferent, on slopes close to running water), Plagiochasmo rupestris-Athalamietum spathysii (xerophilous, photo-sciophilous, chasmo-comophytic, basiphilous, in deep cavities of volcanic and sedimentary rocks) and Homalothecio aurei-Scleropodietum touretii (meso-xerophilous, photo-sciophilous, terricolous, edaphically indifferent, in rocks and humiferous slopes). Studies of the dynamics of the communities were undertaken.  相似文献   

10.
The species of Bucephalus from the eel Anguilla anguilla of the north-eastern Tunisian lagoons was identified as B. anguillae which was recently described by pakulová et al. (2002) from the Adriatic coast of Italy. In order to confirm that this eel digenean is distinct from B. polymorphus von Baer, 1827 present in other freshwater fishes, we investigated the life-cycle of this species. Surveys in the wild and experimental studies have shown that the life-cycle of B. anguillae is completed in brackish environments, with the lamellibranch Abra tenuis as the first intermediate host and the cyprinodontid fish Aphanius fasciatus as the second intermediate host. This life-cycle differs from that of B. polymorphus and can be considered as an additional argument for the distinction of these two morphologically similar species.  相似文献   

11.
Résumé Le nid desMessor en général est formé d'un puits principal s'enfonçant très profondément dans le sol et duquel se détachent plusieurs chambres et galeries latérales. Celui deM. ebeninus présente deux parties: l'étage supérieur, sec en été, est transformé en grenier; l'étage inférieur arrive à la limite de la nappe phréatique: c'est l'abri de la reine et du couvain.Des expériences montrent que la reine et les ouvrières creusent les parties humides du sol. L'importance du travail effectué dépend du volume de la société. Plus le nombre des ouvrières actives est élevé, plus le réseau des galeries s'étend et se développe.La structure de la fourmilière, le volume des chambres et des greniers ainsi que leur emplacement par rapport au puits principal dépendent de la direction prise par l'eau qui s'infiltre ou s'accumule.Une sécheresse de cinq mois et la chaleur de l'été refoulent les fourmis vers les couches profondes du sol à la recherche d'un milieu humide et plus clèment.
Summary The nest ofMessor is generally formed of a main shaft dig down deep into the earth from which several chambers and lateral galleries branch out. the nest ofM. ebeninus cosists of two parts, the upper floor, dry in summer, is transformed into granary; the lower floor, whose lower limits reach the aquatic stratum, becomes the shelter for the queen and his brood.Experiments show that the queen and the workers dig the humid parts of the soil. The importance of this work is a function of the size of the colony. The higher the number of the workers the more developed the tunnels become.The structure of the ant nest, the volume of the chambers and granaries, their placement in relation to the main shaft is a function of the direction of the seeping and accumuled water.The five months period of aridity and hot summer forces ants to go into deeper strata of soil until they find a humid and more favourable conditions.
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12.
《Geobios》1988,21(4):523-529
This paper describes a new species of Apodemus,A. agustii, a Middle Pliocene Muridae from the Guadix-Baza basin. Its morphology is far from that postulated as more frequent in Apodemus: its molars crowns are relatively high: there is no connection between t6 and t9 in M1 and M2. Taking in account this and its age, it is placed in an evolutionary branch, convergent with “Rhagapodemus” morphotype.  相似文献   

13.
Study of a new species of an ursid, Hemicyon mayorali of Tarazona de Aragon in Spain. This species differs from the other species of the genus by the lengthening of the snout and the morphology of M2.  相似文献   

14.
(1) In this paper, differences among the five genera constituting the tribe Cimi cifugeae of the family Ranunculaceae are discussed. Beesia, the first genus, with compound cymes and flowers bearing neither petals nor staminodes, is different from the other four genera with simple or compound racemes and flowers bearing either petals or staminodes, and may occupy a primitive position within the tribe. As to the other four genera, Souliea is characterized by the stem without basal leaf but with 2~5 sheath-like cataphylls, the sepals being deciduous but not caducous, moderate in size and petaloid, the petals being much smaller than sepals, but pink in color and more or less petaloid, the pollen grains being pan tocolpate or pantoporate, the carpels being 1~3 per flower, when mature forming dry linear follicles conspicuously reticulate on the surface and dehiscent along the ventral suture, and the seeds being reticulate-foveolate on the surface. These diagnostic characters indicate clear ly that Souliea might have deviated from the lineage formed by the next three genera, i. e. Anemopsis, Cimicifuga, and Actaea, which have their own well-recognizable diagnostic characters. Anemopsis is characterized by the normally developed basal leaf, the racemose inflorescence with sparse and few long pedicellate flowers, the sepals 7~10 in number, mod erate in size, and petaloid, the petals slightly smaller than sepals, the tricolpate pollen grains, the carpels 2~4 per flower, stalked, when mature forming dry oblong follicles with transverse veins on the surface, and the seeds with scaly membranous wings. Cimicifuga is distinguished by the normally developed basal leaf, the caducous, small, often sepaloid sepa ls, the organs of the second floral whorl sometimes with empty sterile anthers being stamin odes not petals, the tricolpate pollen grains, the carpels 1~8 per flower, when mature form ing dry oblong or ovoid follicles with transverse veins on the surface, and the seeds usually with scaly membranous wings. The last genus Actaea is different by the basal leaf trans formed into a small scale, the caducous, small, often sepaloid sepals, the organs of the sec ond floral whorl being clawed petals, the pollen grains with 3(4~6) colpi, carpel 1 per flow er, when mature forming a fleshy indehiscent berry smooth on the surface and without any veins, the seeds roughish or slightly rugose, neither foveolate nor winged on the surface, and the advanced most asymmetric karyotype. According to the diagnostic characters given above, we believe that Beesia, Souliea, Anemopsis, Cimicifuga, and Actaea do represent five independent genera, and the treatment of the tribe Cimicifugeae including these five genera in it by Hutchinson (1923), Janchen (1949) and some other authors, has precisely shown the taxonomic diversity within the tribe. We are therefore unable to accept the treatment published by Compton et al. (1998) to lump the two genera, Souliea and Cimicifuga, into the genus Actaea. (2) Compton et al. (1998, 1997) found out that the Chinese plants previously identified by various authors as Cimicifuga foetida L., in which the terminal and lateral racemes of the compound raceme flower more or less simultaneously, differ from the true C. foetida L. in northern Asia, in which the terminal raceme of the compound raceme flowers before the lateral ones, and thus restored the species name Cimicifuga mairei Lévl. , which was formerly reduced to the synonymy of C. foetida L. , for the Chinese plants. After examining the specimens collected from Siberia and from Southwest China we failed to find out any other differences in both vegetative and reproductive organs between the plants of the two regions, and we consider that it is better to treat the populations in Southwest and Central China as a geographical variety of Cimicifuga foetida L. A new combination, Cimicifuga foetida L. var. mairei (Lévl.) W. T. Wang & Zh. Wang, is thus made. (3) 3 species of Delphinium, 1 species and 1 variety of Clematis are described as new.  相似文献   

15.
Vingt-deux puces collectées lors de captures de Acomys dimidiatus et Gerbillus dasyurus dans les montagnes de Ras Al Khaimah aux Émirats arabes unis ont été identifiées comme appartenant à deux espèces. Un nouveau taxon est décrit dans le genre Nosopsyllus

http://www.zoobank.org/urn:lsid:zoobank.org:pub:ACB8C547-5A7C-4D45-BBC3-2ABD705FE797  相似文献   


16.
The speciesOstorhinchus fleurieu Lacepède, 1802 is recognized as a senior synonym ofApogon aureus (Lacepède, 1802) on the basis of diagnostic colour features of Lacepède’s illustration of the species (after Commerson). The species is redescribed and a neotype designated. The synonymy of the species is discussed in the light of the history of Commerson’s and Lacepède’s work.Nectamia is replaced byOstorhinchus as a subgenus ofApogon.  相似文献   

17.
Résumé Les cellules de Sertoli du testicule de Lacerta vivipara ont été étudiées en microscopie électronique chez des animaux récoltés entre le printemps et l'automne pendant deux années et chez des animaux hypophysectomisés en automne.Ces cellules contiennent de nombreuses mitochondries de petite taille à crêtes lamellaires, des ribosomes libres, un reticulum endoplasmique lisse moyennement développé, plusieurs petits dictyosomes formant l'appareil de Golgi, des liposomes et des microtubules. Elles renferment aussi de nombreux corps denses de grande taille qui paraissent être de nature lysosomiale. Le glycogène a été particulièrement étudié. Il est formé de particules dispersées au hasard dans le hyaloplasme. Des variations saisonnières dans la teneur en glycogène ont été notées. Chez les hypophysectomisés, les cellules de Sertoli contiennent de grandes quantités de ce métabolite dont les particules sont concentrées dans des petites plages, souvent autour des liposomes.Les rôles possibles des cellules de Sertoli sont discutés: soutien et apport de nourriture aux cellules germinales, production d'hormones et phagocytose des corps résiduels. Les variations de la teneur en glycogène sont également discutées.
The fine structure of the lizard testisII. The Sertoli cells. Study of the glycogen
Summary Sertoli cells of the testis of Lacerta vivipara have been studied electron microscopically in animals obtained between spring and autumn during two years and in animals hypophysectomized in autumn.These cells contain numerous small mitochondria with lamellar cristae, free ribosomes, smooth endoplasmic reticulum moderately developed, several small dictyosomes forming the Golgi complex, lipid droplets and microtubules. There are numerous dense bodies of large size with an heterogeneous content which seem to be of lysosomial nature. Glycogen consists of particles dispersed at random in the hyaloplasm. Seasonal variations in the content of glycogen are noted. In hypophysectomized animals Sertoli cells contain large amounts of that metabolite whose particles are concentrated in small areas often around the lipid droplets.Possible role of the Sertoli cells concerning mechanical support and nutrition of the germinal cells, production of hormones and phagocytosis of residual bodies are discussed. The variations in the glycogen content are also discussed.
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18.
Morphological features of flowers and inflorescences from 13 of 14 species of subtribe Leiboldiinae are analyzed, with the goal of identifying characters with taxonomic value for the delimitation of genera and species. The principal characters to recognize genera in the subtribe are: presence of palaea on the receptacle (Bolanosa), number of series in the involucre and pappus (Stramentopappus), shape of the apices of the phyllaries (Lepidonia), and colour and duration of the pappus. At the specific level, the more important characters are diversity and distribution of trichomes, colour of florets and differences in the sculpturing of the surfaces of the petals.  相似文献   

19.
The present experiments were carried to investigate the effects of some growth factors (FGFs, IGF-1) on the development of limb buds in the slow-worm (Anguis fragilis L.). This serpentiform reptile is devoid of legs in adulthood; but anlagen of limbs appear during embryonic life; their existence is only temporary: their growth ceases, they regress and disappear before hatching. Treatment of embryos was performed either by injection of the drugs around the limb buds or by application of small fragments of cellulosic paper soaked in the growth factors. The embryos were treated (27 by injection, 24 by application of cellulosic paper) at the stage of the allantoic bud 0.2 mm to 0.5 mm long and at an older stage (allantoic bud 1.8 mm to 4 mm long) (21 embryos treated). The administered growth factors were FGF-2, FGF-4 and IGF-1. Dosages were around 1 000 to 3 900 ng. Anterior limb buds display only very weak sensitivity to the effect of the applied growth factors: only a small proportion of the treated embryos presented a weak hypertrophy of these buds; however, after application of a fragment of cellulosic paper soaked in FGF-2, two thickening of the somatopleure in a embryo and two salient buds in another developed in the territory of the limb, propably representing anlagen of supernumerary limbs. In 25% of the embryos treated at the stage of the allantoic bud 1.8 to 4 mm long, the anlagen of the posterior limbs were greatly stimulated under the action of FGFs and IGF-1: the volume of the treated limbs was several times greater than the one of control limbs; histological study showed in the hypertrophied buds, numerous mitoses in the mesoblast and an apical ridge which did not degenerate. These results are in agreement with previous experiments and they show that it is possible to check experimentally the evolutive regression of the limbs of Anguis embryos.  相似文献   

20.
Résumé L'ultrastructure des cellules interstitielles du testicule de Lacerta vivipara a été étudiée entre le printemps et l'automne pendant deux années.Le retioulum endoplasmique lisse, et les mitochondries à crêtes tabulaires sont les organites les plus remarquables comme dans les autres cellules productrices de stéroïdes, mais les liposomes et l'appareil de Golgi sont bien représentés aussi.Les variations ultrastructurales les plus significatives apparaissent entre le printemps et le début de l'été. Au printemps, alors que les caractères sexuels secondaires sont hypertrophiés, un système remarquable de vésicules et de vacuoles se développe à partir du reticulum et probablement aussi du Golgi. Au début de l'été, lorsque les caractères sexuels secondaires sont atrophiés, les vacuoles sont moins nombreuses et le reticulum forme un réseau dense de tubules typiques, souvent étroitement associés aux liposomes; les crêtes mitochondriales sont gonflées.Ces images sont discutées en fonction de l'activité saisonnière d'élaboration d'hormones. L'hypertrophie des systèmes membranaires au printemps correspond probablement à la production ou (et) à l'excrétion des hormones androgènes. Au début de l'été, la cellule n'élabore pas d'androgènes, mais n'est peut-être pas complètement inactive: elle pourrait stocker des précurseurs hormonaux.
The fine structure of the lizard testisI. The interstitial cells
Summary Interstitial cells of the testis of Lacerta vivipara have been studied electronmicroscopically in animals obtained between spring and autumn.Smooth endoplasmic reticulum and mitochondria with tubular cristae are the most prominent organels, lipid droplets and Golgi apparatus being also well developed.The most significant ultrastructural changes occur between spring and the beginning of summer. In spring, during the hypertrophy of secondary sexual characters, a conspicuous system of vesicles and vacuoles originates from the smooth endoplasmic reticulum and probably also from the Golgi apparatus. At the beginning of summer, when secondary sexual characters are atrophied, vacuoles are less prominent and the smooth endoplasmic reticulum consists of a dense network of typical tubules, often closely associated with the lipid droplets; the cristae of the mitochondria are swollen.These ultrastructural findings are discussed in relation to the production of hormones. The hypertrophy of membrane systems in spring corresponds presumably to production or (and) release of androgen hormones. In the beginning of summer the cell does not produce androgens, but probably is not completely inactive: it may store precursors of hormones.
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