|
|
|
| Registros recuperados: 42 | |
|
|
| Stock, J.H.. |
| Lichomolgus longicauda (CLAUS, 1860), is recorded from the gills of Sepia officinalis, captured on 5 different occasions in the North Sea and the Dutch Waddensea. This means a northward extension of the range of this species of more than 8 degrees of latitude. Figures of the parasite have been provided, and the literature bearing on the species has been reviewed. |
| Tipo: Article / Letter to the editor |
|
| Ano: 1956 |
URL: http://www.repository.naturalis.nl/record/504995 |
| |
|
|
| Stock, J.H.. |
| DE PYCNOGONIDEN- FAMILIE AUSTRODECIDAE Toen mij, in 1954, uit Oslo een verzameling Pycnogonida van de „Norwegian Scientific Expedition to Tristan da Cunda 1937—1938“ ter bewerking werd opgezonden, kon ik niet vermoeden dat deze kleine collectie aanleiding zou geven tot een uitgebreide revisie van een gehele familie. In het Noorse materiaal van Tristan da Cunha bevond zich evenwel één Austrodecus soort, die sterk geleek op een reeds beschreven vorm van de Antarctische Austrodecus glaciale. Om geheel zeker te zijn van de determinatie vroeg ik enig vergelijkingsmateriaal van deze vorm ter leen aan het British Museum (Natural History) te London. Tot mijn verrassing bleek niet alleen het materiaal van Tristan da Cunha tot een andere soort te behoren, doch bleek... |
| Tipo: Article / Letter to the editor |
|
| Ano: 1957 |
URL: http://www.repository.naturalis.nl/record/505120 |
| |
|
|
| Stock, J.H.. |
| In September and October 1950, Mr. C. Swaneveld, of Zierikzee, and Mr. Jac. Viergever, of Serooskerke, collected some rich samples of Copepods, found alive in the branchial sac of certain species of Tunicates. The greater part of the Tunicates belonged to the Ascidian-species Ascidiella aspersa (O. F. Müller.) The peculiar little commensal lives in the branchial cavity, often in considerable numbers, with their posterior antenna fixed to the body wall of the Ascidian. The species of the genus Notodelphys stand lowest in the scale of species adapted to this curious mode of life : I observed them moving quickly through the water outside the Tunicate, in a jumping way. Especially when the water contains little oxygen, the animals leave their host through the... |
| Tipo: Article / Letter to the editor |
|
| Ano: 1951 |
URL: http://www.repository.naturalis.nl/record/504809 |
| |
|
| |
|
|
| Stock, J.H.. |
| The grunion, Leuresthes tenuis (AYRES) (family Atherinidae), a fish with a distribution limited to coastal southern California, U.S.A., and Lower California, Mexico, yielded the recently described copepod Caligus olsoni PEARSE, 1953, and still another parasitic copepod which proved to be an undescribed species of the genus Bomolochus. The species was collected by MR. ANDREW C. OLSON, Assistant Professor of Zoology at San Diego State College, who entrusted me with the material for description. |
| Tipo: Article / Letter to the editor |
|
| Ano: 1955 |
URL: http://www.repository.naturalis.nl/record/505090 |
| |
|
|
| Nijssen, H.; Stock, J.H.. |
| An alien amphipod, Gammarus tigrinus Sexton, has been observed in the Netherlands, mainly in oligohaline waters. It has had an “explosive” development in the Yssellake (the former Zuydersea) and occurs also in a great number of inland waterways in the province of North-Holland (fig. 1). It co-exists with, and often outnumbers, the local gammarids, G. pulex, G. zaddachi and G. duebeni. It is expected that the extension of its range will continue next years; fig. 2 illustrates the range of this introduced species in autumn 1965. Since Irish specimens of G. tigrinus were released in 1960 in the Yssellake, it is not clear whether the Dutch populations originate from the Irish stock, or whether that they were accidentally, e.g. in ballast tanks, carried to the... |
| Tipo: Article / Letter to the editor |
|
| Ano: 1966 |
URL: http://www.repository.naturalis.nl/record/505062 |
| |
|
| |
|
| |
|
| |
|
|
| Vos, A.P.C. de; Stock, J.H.. |
| Three new ostracod species, each belonging to a new genus, were described by the first author (DE VOS, 1953). They had been found on the body and the legs of Limnoria lignorum, the well-known woodburrowing isopod. Since then, we have been looking for commensals in several new lots of European Limnoria, and in this way we obtained valuable new data on morphology and distribution of two of the three ostracod species described. Moreover, Dr. Robert I. MENZIES, La Jolla, California, kindly sent us a beautiful lot of ostracods from Limnoria tripunctata MENZIES, an isopod species from the Pacific coast of America, found in test-blocks placed at about 7 feet below mean tide level, and collected in the course of the marine wood-borer studies, Project NR 163—084 at... |
| Tipo: Article / Letter to the editor |
|
| Ano: 1956 |
URL: http://www.repository.naturalis.nl/record/505049 |
| |
|
|
| Stock, J.H.. |
| During the preparation of a report dealing with poecilostomes associated with holothurians, it was found desirable to obtain more information concerning a number of genera formerly described. Through the courtesy of Dr. T.Wolff of the Zoologisk Museum of Copenhagen, I was able to reexamine the type-specimens of Scambicornus hamatus, described by HEEGAARD, 1944, from a Japanese holothurian. |
| Tipo: Article / Letter to the editor |
|
| Ano: 1964 |
URL: http://www.repository.naturalis.nl/record/505173 |
| |
|
|
| Stock, J.H.. |
| While studying the parasitic copepods of the Dutch Waddensea, at the Zoological Station Den Helder, I came across a species of Bomolochus from the gills of the Black Sole, Solea solea (L.). Except for the second leg, the various appendages resembled those of B. soleae CLAUS, as figured by TH. & A. SCOTT in their Ray Society Monograph (1912—13). According to them, the endopod of the second leg has narrow joints, like the exopod. They stated that the second and third leg have about the same structure. In my material, however, the endopod of the second leg has widened joints; second and third legs have, therefore, quite a different aspect. Of TH. and A. SCOTT’S material, 2 samples remained**) in the collections of the British Museum (Natural History),... |
| Tipo: Article / Letter to the editor |
|
| Ano: 1953 |
URL: http://www.repository.naturalis.nl/record/504801 |
| |
|
|
| Dennert, H.G.; Dennert, A.L.; Kant, P.; Pinkster, S.; Stock, J.H.. |
| 1. The real identity has been studied of juvenile gammarids, that were found in the fresh-water tidal region of the River Slack (France), 3 to 4 km inland of the mouth of its estuary. At the outset, these juveniles were (on basis of their morphology) considered to belong to Gammarus salinus. 2. Rearing demonstrated that the juveniles in question developed into adult Gammarus zaddachi. This indicates that the morphological criteria used in discriminating between G. salinus and G. zaddachi fail in juvenile material. Several morphological criteria are discussed and tested. It appears that a 100% certain key character does not exist, meaning that it is not possible to identify with absolute certainty all individuals in mixed populations of the two species. 3.... |
| Tipo: Article / Letter to the editor |
|
| Ano: 1969 |
URL: http://www.repository.naturalis.nl/record/504231 |
| |
|
|
| Pinkster, S.; Stock, J.H.. |
| Systematic sampling proved that members of the Echinogammarus Simonigroup are the dominant freshwater amphipods in the southern half of the Iberian peninsula. It became clear, that the presence (as recorded in literature) of E. simoni in the system of the river Duero was due to confusion with members of the genus Eulimnogammarus. The systematical position of the simoni – group within the genus Echinogammarus is discussed and comparative descriptions of all the members of this group are given, along with a key for their identification. Where possible, notes are given on the variability and ecology of the different species. |
| Tipo: Article / Letter to the editor |
|
| Ano: 1972 |
URL: http://www.repository.naturalis.nl/record/505553 |
| |
|
|
| Stock, J.H.. |
| It will be difficult to imagine a more variable group of species than the European representatives of the genus Callipallene Flynn, 1929. He, who wants to identify the European species and sub-species of the genus Callipallene, may easily get stuck, for if he does not dispose of enough material for comparison, he will have great trouble in distinguishing them. Yet, though difficult to define, certain differences do exist between the forms. It must be pointed out that non-adult specimens are almost unidentifiable. With the aid of our drawings and descriptions, however, it will be possible to identify full-grown females and ovigerous males. |
| Tipo: Article / Letter to the editor |
|
| Ano: 1952 |
URL: http://www.repository.naturalis.nl/record/504956 |
| |
|
|
| Stock, J.H.. |
| Two morphologically and ecologically different forms within the genus Gammarus, known as G. plumicornis Costa, 1853 and G. aequicauda (Martynov, 1931), are interfertile in experiments and produce a vital F1. In nature, however, heterogeneous couples are rare, although not altogether absent. It is supposed that plumicornis and aequicauda are two former subspecies, which – owing to an overlap in their present distribution areas – have not developed sufficient isolating mechanisms to prevent hybridization. |
| Tipo: Article / Letter to the editor |
|
| Ano: 1969 |
URL: http://www.repository.naturalis.nl/record/505582 |
| |
|
| |
|
|
| Bourdon, R.; Stock, J.H.. |
| Four bopyrids are described. Pleurocryptina indica Nz. & B. à 8., 1929, is recorded from Mauritius; it was previously known from the East Indies. Bopyrina brachytelson Nz. & B. à 8., 1923, is compared with other members of the genus. Metacepon pleopodata n. sp., a parasite of Litocheira setosa collected in Amboina (Indonesia), is a species with an aberrant male morphology. Another species, parasitic on Metopograpsus oceanicus in Sumbawa (Indonesia), is tentatively attributed to Megacepon, a genus with uncertain affinities. |
| Tipo: Article / Letter to the editor |
|
| Ano: 1979 |
URL: http://www.repository.naturalis.nl/record/505196 |
| |
|
|
| Stock, J.H.. |
| Two Pycnogonida only have been collected during the cruises of the meteorological vessel ”Cirrus” in deep plankton tows, but both specimens, each belonging to a different species, proved to be of considerable interest. I am indebted to Mr. C. L. Bekkering and Mr. S. D. Koning, who presented this precious material to the Zoölogisch Museum, Amsterdam. The one specimen belongs to a relatively well-known species, Callipallene acus (Meinert, 1898). On the basis of this material, our knowledge on the external morphology of this species, more particularly on the polymorphism in the legs, could be extended. |
| Tipo: Article / Letter to the editor |
|
| Ano: 1964 |
URL: http://www.repository.naturalis.nl/record/505022 |
| |
|
|
| Stock, J.H.. |
| Fifteen years ago, H. Helfer in his paper ”Einige neue Pantopoden aus der Sammlung des Zoologischen Museums in Berlin” (Sitz. Ber. Ges. Naturf. Fr., Berlin 1937 (1938), pp. 162—185) established 5 new genera, each based on a new species, 2 new species belonging to known genera, and 3 new varieties. Since then, several authors have expressed their doubt about the validity of Helfer’s new forms. Indeed, Helfer’s descriptions and figures leave doubt as to the affinities of the material. Often the descriptions and the figures are contradictory e.g., in Heteronymphon kempi var. dimorpha the figure of the chelifore shows one suture too much, and in Pycnosoma batangense a suture too little. |
| Tipo: Article / Letter to the editor |
|
| Ano: 1953 |
URL: http://www.repository.naturalis.nl/record/505138 |
| |
| Registros recuperados: 42 | |
|
|
|
