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Registros recuperados: 119 | |
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Schuurmans-Stekhoven Jr., J.H.. |
In 1933 Dr. G. J. van Oordt together with a number of biological students made an excursion to the Camargue. During that trip he collected some samples of mud from brackish ponds and pools in the Rhône Delta, which collection he entrusted me for further research. At this place I will bring him my renewed thanks for his contribution to nematology. Although the collection was not great, it brought to light some interesting new species. Moreover it allows us to say something about the penetration of marine forms into brackish waters. A comparison of the list of forms given below with the lists I have given from Nematodes found to occur in the former Zuidersea shows that the penetration of marine forms into brackish waters in the Mediterranean is performed in... |
Tipo: Article / Letter to the editor |
Palavras-chave: 42.79. |
Ano: 1942 |
URL: http://www.repository.naturalis.nl/record/318897 |
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Schuurmans-Stekhoven Jr., J.H.. |
In June 1932 my friend Prof. Dr. G. C. Hirsch made some biological studies at the marine biological laboratory of Palma di Mallorca. He was accompanied by Dr. E. Ries, at that time Rockefeller Fellow. Both did collect for me some samples of marine sediments from which I have picked out the freeliving marine nematodes for further study. In the same year Dr. A. Oosterbaan made an excursion to Ibiza together with some other geological students and brought home from there for me some samples of mud with marine nematodes. The result of the 3 mentioned small collections, of which that of Hirsch is the most important, will be given in this paper. Next to a comparatively great number of typical mediterranean marine nematodes, a restricted number has a more... |
Tipo: Article / Letter to the editor |
Palavras-chave: 42.79. |
Ano: 1942 |
URL: http://www.repository.naturalis.nl/record/318272 |
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Engel, H.. |
Diagnosis. Aplysiidae of conical form, narrower in front, wide and obliquely truncate behind. Integument more or less warty, the warts bearing villi; warts and villi being wholly retractile. Parapodia united, save for a dorsal slit; the free lobes covering the slit leave two conspicuous respiratory openings, one at the posterior and one at the anterior 'end. The posterior respiratory opening, corresponding to the mantle-siphon, lies about in the middle of the posterior disc, the anterior opening outside the disc, somewhat in front of the disc's anterior margin. Shell solid, hatchetshaped, the free spire calloused. Penis armed or unarmed. Radula with inconspicuous, often reduced rhachidian tooth and many laterals with long simple cusps. Short history of the... |
Tipo: Article / Letter to the editor |
Palavras-chave: 42.73. |
Ano: 1942 |
URL: http://www.repository.naturalis.nl/record/318863 |
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Jonker, F.P.. |
Of the family Oenotheraceae the genus Jussieua is the only one occurring in Suriname. The peculiar Oocarpon torulosum (Arn.) Urb., which has been recorded from Amazonian Peru, Brazil, British and French Guiana, Cuba and Santo Domingo, has up till now not been collected in the colony, but on account of its presence in the neighbouring countries it is there also to be expected. As for the name of the only Suriname genus, it was spelled by LINNAEUS in Genera Plantarum, ed. I (1737), p. 126, Jussieua but afterwards in his Flora Zeylanica (1747), p. 75, changed in Jussiaea. |
Tipo: Article / Letter to the editor |
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Ano: 1942 |
URL: http://www.repository.naturalis.nl/record/535162 |
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Regteren Altena, C.O. van. |
Part I of this monograph has been published in volume 10 of this Journal, pp. 241—320, 1938. Preparing this second part I met with the help and assistance from many persons and institutes again, for which I express my most cordial thanks here. The figures illustrating this paper have been drawn once more by Mr. L. P. Pouderoyen, while the „Zoologisch Insulinde Fonds” supplied the cost of these illustrations. |
Tipo: Article / Letter to the editor |
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Ano: 1942 |
URL: http://www.repository.naturalis.nl/record/505875 |
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Schilder, F.A.. |
The Cypraeacea of the Cosijn collection and from the localities M1—M 262 of the Mijnwezen collection were already discussed by me in a previous paper 3). Recently some new material was sent to me by Dr. C. O. van Regteren Altena; these new shells partly derive from the localities M 263—M 347 of the Mijnwezen collection 4), partly they belong to the Dubois collection of the Rijksmuseum van Natuurlijke Historie at Leiden. I thought it useful to include in the present study all the Cypraeacea of the Cosijn and Mijnwezen collections, whether already dealt with before or not, as well as the shells from Sonde in the collection K. Martin (R. G. M. L.) 5), the Cypraeacea of the Dubois collection, and some other specimens examined in Dutch collections. Thus the... |
Tipo: Article / Letter to the editor |
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Ano: 1942 |
URL: http://www.repository.naturalis.nl/record/505674 |
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Bremekamp, C.E.B.. |
Among the most aberrant types of pollen grains found in plants which have been referred to the family Acanthaceae, are those of the genera Meyenia N. ab E. and Thomandersia Baill. Although the pollen grains were described by LINDAU under different names, those of the first genus as cogwheel-shaped and those of the latter as lenticular, they are really very similar: in both genera they are depressed globose, provided with five or more meridional grooves extending from the equator to about halfway the poles, and without clearly circumscribed germ pores. The difference between the two kinds of grains lies in the presence or absence of ribs: in Meyenia the grooves are borne on the top of ribs separated from each other by shallow depressions, whereas in... |
Tipo: Article / Letter to the editor |
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Ano: 1942 |
URL: http://www.repository.naturalis.nl/record/534928 |
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Graner,E. A.. |
The methods used in obtaining polyploid cassava (Manihot utilissima Pohl) by colchicine treatment were described in detail. Two solutions of colchicine were tried, one at 0.5% and other at 1.0%, both giving identical results in producing many altered plants. The chromosome number of the altered plants was determined and [a correlation between chromosome duplication and increase of the major diameter of stomata was found. Size of stomata in cassava serves to identify poliploids individuals if the plant produced by treatment is not a chimera, a very frequent event in producing polyploid cassava by colchicine. It was emphasized that the plants obtained by treatment were a type of chimera, with the aerial part polyploid and the subterranean base diploid. The... |
Tipo: Info:eu-repo/semantics/article |
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Ano: 1942 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0006-87051942000200001 |
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Heimans, J.. |
In the winter and early spring of 1916 Mrs. Anna Weber-van Bosse at her hospitable residence near Eerbeek initiated me in the study of Freshwater Algae. For several years after that date in numerous trips all over this country I collected and studied some thousands of samples from all kinds of freshwater ponds and lakes, canals and streams. The Desmids soon drew my special attention, when an unexpectedly rich and varied Desmid flora was found in certain fens and ponds in the diluvial and moor districts of our country. |
Tipo: Article / Letter to the editor |
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Ano: 1942 |
URL: http://www.repository.naturalis.nl/record/526352 |
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Brieger,F. G.; Forster,R.. |
The present paper gives some observations on the tumour formation and other abnormalities observed in the interspecific hybrids, Nicotiana glauca x N. Langsdorffii and N. glauca x N. Sanderae. Without entering into a detailed discussion of the literature and the various speculations proposed by Kostoff and Whitaker about the causes of tumour formations or on the relations between "spontaneous" and pathogenic tumours (Kostoff, Levine and others), two new observations are described. 1) The abnormalities in the two above mentioned hybrids are quite different. As already reported by other authors, the hybrids N. glauca x N. Langsdorffii are initially quite normal and vigorous, while tumours and other proliferations, on the stem, the stem base and the root... |
Tipo: Info:eu-repo/semantics/article |
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Ano: 1942 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0006-87051942000700002 |
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Florschütz, F.; Jonker, F.P.. |
Die Pflanzendecke unseres Landes hat während des Quartärs grosse Änderungen erlitten. Dies wird besonders deutlich beim Vergleich der limburgischen fossilen Flora, wie sie in einer vortrefflichen Arbeit des Ehepaares REID (Lit. 1) beschrieben ist, mit der gegenwärtig einheimischen Vegetation. Im allgemeinen wird die erwähnte Flora für jungtertiär gehalten, jedoch ist ihre Stelle im Pliozän umstritten. Von den ungefähr 240 Phanerogamen, von welchen sich Reste im Ton von Reuver, Swalmen und Brunssum vorfanden, sind laut der Berechnung von E. M. REID nur 12% heute indigen und 88% exotisch; mehr als die Hälfte der letzteren sind identisch mit rezenten sino-amerikanischen Arten (Lit. 2). |
Tipo: Article / Letter to the editor |
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Ano: 1942 |
URL: http://www.repository.naturalis.nl/record/535109 |
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Florschütz, F.; Wassink, E.C.. |
Die Frage nach der Art, wie die nordwesteuropäische Calluna-Heide entstanden ist, und wann dies geschah, wurde in den letzten Jahren erneut diskutiert. In der vorliegenden Mitteilung wird versucht, auf Grund der Resultate pollenanalytischer Untersuchungen kleiner Moore im Heidegebiet der niederländischen Provinz Drenthe einen Beitrag zur Lösung dieses Problems zu geben. Der von uns begangene Weg wurde bereits 1931 von OVERBECK (1) *) vorgeschlagen. Dieser Autor brachte damals auch schon ein Beispiel derartiger Untersuchungen in der Bearbeitung kleiner Moore auf der Vegesacker Geest in der Nähe von Bremen: des Moores bei Lilkendey und des Garlstedter Moores. Die Erscheinung, welche hier wichtig ist, ist folgende: In den Diagrammen der Ablagerungen beider... |
Tipo: Article / Letter to the editor |
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Ano: 1942 |
URL: http://www.repository.naturalis.nl/record/535108 |
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Beets, C.. |
Bekanntlich hat K. Martin zweimal (1933, 1935, vgl. auch 1937) einige Mollusken aus dem angeblichen Oberoligocän der Insel Buton beschrieben, auf deren merkwürdige Charaktere er ausdrücklich hinwies. Ich selbst konnte seine Feststellungen an Hand reichlichen neueren Materials nur bestätigen und ergänzen 1): wenn man, es sei an dieser Stelle wiederholt, diese Molluskenfauna auf ihren Zusammenhang mit anderen Faunen hin prüft, so kommt man bald zu der Einsicht, dass zu anderen palaeogenen Faunen fast gar keine Beziehungen bestehen, jedenfalls nicht zu jenen benachbarter Erdteile (diese Verwandtschaftsbeziehungen sind vielleicht bloss Konvergenz-Beispiele); wirklich nahe Beziehungen bestehen nur zu der Neogenfauna nahegelegener Teile des ostindischen... |
Tipo: Article / Letter to the editor |
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Ano: 1942 |
URL: http://www.repository.naturalis.nl/record/505633 |
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Westerveld, J.. |
The Pasoemah region S of the Goemai Mts. in W. Palembang is largely occupied by Quaternary volcanics, which form a sharply dissected plateaulike country, whose surface gradually slopes downward in an ENE direction from ± 1000 m to ± 300 m above sea-level, conformably to the courses of the Selangis and Lematang Rivers above their point of confluence. Where the Lematang River unites with the Moelak River, the acid welded tuffs of the Pasoemah highland, to which attention will be drawn in this paper, are cut off by a steep bluff, formed undoubtedly by retrogressive erosion, which was substantially facilitated by the presence of vertical cleavage planes in the rhyolitic tuff series. In the Goemai Mts., described elsewhere in detail by K.A.F.R. Musper (1937)... |
Tipo: Article / Letter to the editor |
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Ano: 1942 |
URL: http://www.repository.naturalis.nl/record/505700 |
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Kylin, Harald. |
In einem jüngst erschienenen Aufsatz schreibt Du Rietz (1941 S. 6): ”Pylaiella rupincola (Aresch.) Kylin ist mit Conferva litoralis L. identisch. Kein Grund liegt vor anzunehman‘, dass Linné die auf Ascophyllum an der schwedischen Westküste wachsende Pylaiella litoralis sensu Kylin gekannt und in seine Conferva litoralis miteinbezogen hat. Der Name Pylaiella litoralis (L.) Kjellm. muss deshalb für P. rupincola (Aresch.) Kylin beibehalten werden. Für P. litoralis sensu Kylin schlägt Verf. den neuen Namen Pylaiella Kylinii vor.“ Bei meinen Untersuchungen über Pylaiella litoralis (1933 und 1937) war ich zu der Auffassung gekommen, dass diese Art in sich zwei verschiedene Arten enthielt. Für die eine behielt ich den Namen P. litoralis (L.) Kjellm., die andere... |
Tipo: Article / Letter to the editor |
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Ano: 1942 |
URL: http://www.repository.naturalis.nl/record/526304 |
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Registros recuperados: 119 | |
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