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| Registros recuperados: 14.605 | |
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| Nordhagen, J.R.; Heuch, P.A.; Schram, T.A.. |
| Salmon lice Lepeophtheirus salmonis (Krøyer, 1837) from farmed Atlantic salmon have been implicated in the drastic sea trout and salmon stock declines found in Ireland and Norway. Can salmon lice from farmed and wild fish be distinguished? The hypothesis has been advanced that the treatment of salmon infested with salmon lice with organophosphate pesticides has resulted in the evolution of early maturing, smaller female lice, which are favoured because they have the chance to reproduce before treatment. Salmon lice on wild fish have been reported to be larger and have more eggs in their egg strings (sacks) than lice on farmed fish. The question is whether the size differences between the lice are genetically fixed or an expression of phenotypic plasticity.... |
| Tipo: Article / Letter to the editor |
Palavras-chave: Salmon lice; Origin; Size; Phenotypic plasticity. |
| Ano: 2000 |
URL: http://www.repository.naturalis.nl/record/534287 |
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| Janssen, C.R.. |
| The present study deals with the late-glacial and post-glacial development of the vegetation in the loess region of South Limburg (Netherlands). In the lateglacial time the continental element in the vegetation (Artemisia) is very pronounced, probably due to the particular soil conditions in South Limburg. The zonation of FIRBAS (1949) has been applied to the South Limburg diagrams. Zone I: Tundra, a temporary amelioration of the climate (Bölling time) can be observed. Zone II: Closed pine forests present (Alleröd time). Zone III: In the lower part of the zone Pinus dominant, afterwards Belula. Zone IV: Decrease of the percentages of the herbs; Pinus dominant in the vegetation; first appearance of Corylus. Zone V: Pinus and Corylus dominant; in the lower... |
| Tipo: Article / Letter to the editor |
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| Ano: 1960 |
URL: http://www.repository.naturalis.nl/record/534940 |
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| Lyal, C.H.C.. |
| The genus Calliphara is described. Its 15 species and 6 additional subspecies are classified into 4 species-groups on the basis of the morphology of the male genitalia, and a key is provided for their separation. Calliphara solomonensis sp. nov. from the Solomon Is. and C. vollenhoveni sp. nov. from the Bismarck Archipelago are described. A synonymic catalogue of all species-group taxa within the genus is given. Fifteen lectotype designations are made. The history and relationships of Calliphara are discussed. Notacalliphara gen. nov. is founded for Calliphara rostrata Distant, and Notacalliphara pseudofasciata sp. nov. from New Guinea is described. Paracalliphara gen. nov. is founded for Calliphara flagrans (Walker). |
| Tipo: Article / Letter to the editor |
Palavras-chave: 42.75. |
| Ano: 1979 |
URL: http://www.repository.naturalis.nl/record/317909 |
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| Schepman, M.M.. |
| Amongst the Melanidae of the Leyden Museum, many species were unknown to me, so I submitted them all to the judgment of the late Dr. A. Brot, who declared many of them to be doubtful, which I have indicated in the Catalogue of the Museum by a note of interrogation; a few others, however, seemed also to this much regretted authority to be new to science and so I ventured to describe them as follows. |
| Tipo: Article / Letter to the editor |
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| Ano: 1896 |
URL: http://www.repository.naturalis.nl/record/508546 |
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| Lens, F.; Gasson, P.; Smets, E.; Jansen, S.. |
| The wood anatomy of 16 of the 37 genera within the epacrids (Styphelioideae, Ericaceae s.l.) is investigated by light and scanning electron microscopy. Several features in the secondary xylem occur consistently at the tribal level: arrangement of vessel‐ray pits, distribution of axial parenchyma, ray width, and the presence and location of crystals. The primitive nature of Prionoteae and Archerieae is supported by the presence of scalariform perforation plates with many bars and scalariform to opposite vessel pitting. The wood structure of Oligarrheneae is similar to that of Styphelieae, but the very narrow vessel elements, exclusively uniseriate rays and the lack of prismatic crystals in Oligarrheneae distinguish these two tribes. The secondary xylem of... |
| Tipo: Article / Letter to the editor |
Palavras-chave: Ecological wood anatomy; Epacrids; Ericaceae s.l.; Styphelioideae; Systematic wood anatomy; 42.56. |
| Ano: 2003 |
URL: http://www.repository.naturalis.nl/record/431740 |
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| Breure, A.S.H.; Mogollón Avila, V.. |
| The family Orthalicidae is well represented in Peru but, like in other families, some species are wellknown and others have not been reported on since their original descriptions. In this paper we present new records for well-known species and elucidate the status of several lesser known taxa. Four taxa are described as new: Bostryx chusgonensis sipas, B. fragilis, Scutalus (Scutalus) mariopenai and S. (S.) phaeocheilus altoensis. The following species are recorded as new to the Peruvian malacofauna: Corona pfeifferi, Drymaeus (D.) branneri, and Thaumastus flori. Strophocheilus tenuis Haas, 1955 is now considered synonymous with Thaumastus (Paeniscutalus) crenellus (Philippi, 1867). Plekocheilus conspicuus Pilsbry, 1932 is now placed in the synonymy of... |
| Tipo: Article / Letter to the editor |
Palavras-chave: Anatomy; Distribution; Bostryx; Bulimulus; Corona; Drymaeus; Naesiotus; Peru; Scutalus; Taxonomy; Thaumastus; 42.73. |
| Ano: 2010 |
URL: http://www.repository.naturalis.nl/record/358740 |
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| Janssen, C.R.. |
| Single vegetation plots in forests and bogs in the deciduous and coniferoushardwood formation in northwestern Minnesota were studied according to the field methods of the Zürich-Montpellier system. Plots and species were arranged so that the greatest coincidence of occurrences was obtained. Species that show approximately similar amplitudes were united in sociological groups. Plant communities typified by these groups were placed in a hierarchy. The plant communities appear to intergrade but are not completely continuous. Definite concentrations of occurrences remain present in the ordination. Fourteen main types of vegetation are recognized. Their relations to the environment are discussed, and their relations to vegetation in other regions are indicated.... |
| Tipo: Article / Letter to the editor |
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| Ano: 1967 |
URL: http://www.repository.naturalis.nl/record/534710 |
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| Segal, S.. |
| Hybrids of the Dryopteris spinulosa complex in the Netherlands Kuntze ex Druce (= D. carthusiana X D. cristata) and D. x deweveri Dryopteris x uliginosa (Joh. Jansen) J. & W. ( = D. carthusiana X D. dilatata) have been recorded from several places in the Netherlands. Fern hybrids, generally speaking, can be recognised by the absence of indurated annulus cells (magnifying glass) and by the presence of abortive spores. Often hybrids tend to show, apart from intermediate characters, monstruosities in leaf shape (especially bifurcations), irregular growth of the crown of leaves sprouting from the rhizome, and hybrid vigour. The diagnostic characters of the hybrids are enumerated. Main characters in D. x uliginosa are: the connection of the basal leaf... |
| Tipo: Article / Letter to the editor |
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| Ano: 1971 |
URL: http://www.repository.naturalis.nl/record/528044 |
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| Gordon, Isabella. |
| This report contains an account of a collection of Gorgonids made by Dr. C. J. VAN DER HORST at the island of Curaçao and also of a few specimens collected in the same locality by Ir. G. J. H. MOLENGRAAFF. The Majority of the specimens are taken from Caracas bay at a depth of not more than five metres. The specimens were consigned for report, to the Natural History Department of Aberdeen University through the kindness of Dr. C. J. VAN DER HORST and Dr. L. F. DE BEAUFORT, Director of the Zoological Museum, Amsterdam. Their identification has been checked by Professor J. ARTHUR THOMSON. |
| Tipo: Article / Letter to the editor |
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| Ano: 1925 |
URL: http://www.repository.naturalis.nl/record/503943 |
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| Bremer, P.. |
| In the Netherlands Ophioglossum vulgatum occurs in a wide variety of habitats, like dune slacks, wetlands, unfertilized grassy pastures and pits. Records from woodlands were scarce. After the reclamation of the IJsselmeer polders thousands of acres have been planted with trees; in these woodlands Ophioglossum has been recorded at 11 localities, mostly growing under a canopy of Ash, on calcareous soils consisting of fine sand, boulder clay or clay. |
| Tipo: Article / Letter to the editor |
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| Ano: 1988 |
URL: http://www.repository.naturalis.nl/record/526901 |
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| Stiasny, G.. |
| In einer kurzen Mitteilung über adriatische Tornarien habe ich (4) vor Jahren beiläufig erwähnt, dass im Plankton des Triester Golfes ausser den relativ grossen Tornarien des Balanoglossus clavigerus noch eine zweite kleine Larvenform vorkommt. Diese kleine Tornaria, über welche ich seinerzeit keine näheren Mitteilungen machen konnte, habe ich nun in einigen Exemplaren und in verschiedenen Entwicklungsstadien in meinen Praeparaten aus Triest wiedergefunden und gebe ich im Folgenden eine kurze Beschreibung derselben. Bei genauerer Untersuchung hat sich nämlich ergeben, dass es sich hier nicht etwa um jüngere Entwicklungsstadien des Balanoglossus clavigerus handelt, sondern dass hier eine andere Enteropneusten-Larve vorliegt. Bei früherer Gelegenheit (8, p.... |
| Tipo: Article / Letter to the editor |
Palavras-chave: 42.89. |
| Ano: 1928 |
URL: http://www.repository.naturalis.nl/record/318235 |
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| Ritsema Cz., C.. |
| Close to and much resembling P. lugubris Rits. from Nias (N. L. M. vol. XIV, 1892, p. 215), but smaller (measuring 26 mm. in length) and more vividly colored. Above opaque, the smaller basal half of the elytra, however, shining. — Head dark blue with green tinges, red in the middle beneath. 1st, 2nd and basal half of 3rd antennal joint dark blue, apical half of 3rd joint and the 4th—7th joints yellow, the 7th spotted with black at the apex above, the subsequent joints black. — Prothorax red, front- and basal margins dark blue, the latter surrounding the coxae and invading the intercoxal part. Without any trace of spine or tubercle laterally; the disk flat, strongly punctured, sharply separated from the sides as if it were a piece led in; the sides and... |
| Tipo: Article / Letter to the editor |
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| Ano: 1909 |
URL: http://www.repository.naturalis.nl/record/508454 |
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| Wijnhoven, H.. |
| Terrestrial isopods of the Ooijpolder: part 2. ecology (Crustacea: Isopoda: Oniscidea) From 1991 up to 1998 the isopod fauna of 1464 squares of 100x100 m was sampled in the Ooijpolder. This area is situated along the river Waal, east of Nijmegen (the Netherlands), close to the German border. In part 1 (Wijnhoven 2000) the distributions and habitats of seventeen species of woodlice were discussed. In that paper the basic information on topography, methods, species list and list of first and second order habitats can be found. In this second and last part the ecological information is summarised. First the zoogeographical position of the species is indicated. This proved to be important in understanding the distribution patterns and habitats of the species... |
| Tipo: Article / Letter to the editor |
Palavras-chave: Nederland; Verspreiding; Fenologie; Biotopen; Biologie; Bescherming; 42.74. |
| Ano: 2001 |
URL: http://www.repository.naturalis.nl/record/218616 |
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| Noordeloos, Machiel E.. |
| The knowledge of the macrofungi (mushrooms and toadstools) in Europe, including the Netherlands, is still far from complete. During our studies on this group of organisms in the Netherlands and adjacent Belgium and Germany while preparing a critical identification work, the Flora agaricina neerlandica, a fairly large number of new species has been discovered, and a lot more has become known on the variability, distribution and ecology of the about 2,000 other species that will eventually be included in this Flora. In the period 1987-1996 four volumes have been completed of this standard work (Bas et al., 1988, 1990,1995,1996), three are in preparation, and we hope that early in the twenty-first century, the set of 10 volumes will be finished. The present... |
| Tipo: Article / Letter to the editor |
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| Ano: 1996 |
URL: http://www.repository.naturalis.nl/record/525303 |
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| Registros recuperados: 14.605 | |
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