54 research outputs found
HISTORICAL AND NOMENCLATURAL REMARKS ON SOME MEGATOOTHED SHARK TEETH (ELASMOBRANCHII, OTODONTIDAE) FROM THE CENOZOIC OF NEW JERSEY (U.S.A.)
. In the second issue of Samuel Mortonâs âSynopsis of the Organic Remains of the Cretaceous Group of the United Statesâ published in June 1835, several otodontid shark teeth from Cenozoic formations of New Jersey are named with authorship of Louis Agassiz and meet the conditions of availability of the International Code of Zoological Nomenclatural. It has gone largely unnoticed that some of these names were introduced in this work before their publication in Agassizâs masterpiece âRecherches sur les poissons fossilesâ. The specimens presented by Morton were kept in the John Price Wetherill (1794-1853) collection that found its way into the paleontological collection of the Academy of Natural Sciences of Drexel University, Philadelphia, where most of them have been rediscovered. These teeth are part of the type series upon which Agassiz introduced Lamna obliqua Agassiz in Morton, 1835, Lamna lanceolata Agassiz in Morton, 1835, Carcharias lanceolatus Agassiz in Morton, 1835, Carcharias megalotis Agassiz, 1835 and Carcharias polygurus Agassiz in Morton, 1835, all of these species being referred to the genus Otodus in the present work. In order to secure the nomenclatural stability of the Otodontidae, it is established that Otodus lanceolatus is a junior synonym of Otodus obliquus, that âCarchariasâ lanceolatus belongs to the genus Otodus Agassiz, 1838 and is invalid as a junior secondary homonym of Otodus lanceolatus, that Otodus megalotis is a junior synonym of Otodus auriculatus (Blainville, 1818), and that Otodus polygurus (Otodus polygyrus being an incorrect subsequent spelling) is a junior synonym of Otodus megalodon (Agassiz, 1835). Furthermore, it is shown that the date of publication of Otodus obliquus (Agassiz in Morton, 1835) is 1835 and not 1838 as previously thought
High power multimode fiber amplifier with wavefront reshaping for high beam quality recovery
International audienc
The history, systematics, and nomenclature of Thalattosuchia (Archosauria: Crocodylomorpha)
The use of more than one nomenclatural code is becoming increasingly common in some biological sub-disciplines. To minimize nomenclatural instability, we have decided to establish a higher level systematization for Thalattosuchia under both the International Code of Phylogenetic Nomenclature (âPhyloCodeâ) and the International Code of Zoological Nomenclature (âZoological Codeâ). We undertook a series of phylogenetic analyses with an expanded dataset to examine the origins of Thalattosuchia within Crocodylomorpha, and determined the cladeâs diagnostic characters. Based on these analyses, we provide updated diagnoses for Thalattosuchia and its subclades under both the PhyloCode and Zoological Code. We also introduce two new nomina that are regulated under the PhyloCode (Neothalattosuchia and Euthalattosuchia), and the nomen Dakosaurina, which is registered under both nomenclatural codes. Moreover, we introduce PhyloCode-compliant phylogenetic definitions for Thalattosuchia and its subclades. As we cannot reliably discriminate between the positional hypotheses for Thalattosuchia within Crocodylomorpha, the cladesâ origins are as much of a mystery today as they were over a century ago. However, we hope that using the same diagnostic characters to define the same clades, with the same nomina, under both nomenclatural codes will be an example to others to follow
Silicon photonics frequency shifter based on I&Q dual Mach-Zehnder modulator
We present a fully CMOS compatible frequency shifter device, in a I&Q dual Mach-Zehnder architecture. Frequency shift up to 410 MHz are obtained, with carrier and image sideband extinction from 27 to 51 dB
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En 1808 puis en 1824, Georges Cuvier signala dans la rĂ©gion du Mans la prĂ©sence de restes de crocodiles fossiles Ă partir desquels fut crĂ©Ă©e lâespĂšce Crocodilus maunyi GRAY, 1831. Il avait Ă©tĂ© informĂ© de ces dĂ©couvertes par le naturaliste manceau Louis Jean Charles Maulny (1758-1815) et par Jean Antoine Daudin (1749-1832), premier conservateur du MusĂ©um dâhistoire naturelle du Mans. Faute de figures publiĂ©es, ce matĂ©riel est restĂ© Ă©nigmatique durant deux siĂšcles. Des aquarelles inĂ©dites conservĂ©es dans les archives de Georges Cuvier permettent de dĂ©voiler les spĂ©cimens quâil avait dĂ©crits sous le nom de « crocodiles fossiles des environs du Mans ». Ils comprennent des dents, des vertĂšbres et des portions de mĂąchoires de crocodylomorphes marins et de plĂ©siosauriens dĂ©couvertes dans le MĂ©sozoĂŻque de la Sarthe (Bathonien, Callovien, CĂ©nomanien ?). Un de ces dessins prĂ©sente une dent de pliosaure du Bathonien de Ber- nay-en-Champagne qui serait la plus ancienne dĂ©couverte dâun reprĂ©sentant de ce groupe. Deux autres aquarelles montrent une portion de mandibule dâun crocodylomorphe marin (Thalattosuchia, Metriorhynchidae indĂ©terminĂ©) et une vertĂšbre de plĂ©siosaurien (Plesiosauria indĂ©terminĂ©) du Callovien moyen de Chaufour-Notre-Dame, toujours conservĂ©es au MusĂ©e Vert, le musĂ©um dâhistoire naturelle du Mans. Ces deux spĂ©cimens furent dĂ©couverts en 1816 par un amateur local, le docteur EusĂšbe Marie Tendron (1778-1854). Crocodilus maunyi GRAY, 1831 reste nĂ©anmoins considĂ©rĂ© comme un nomen dubium au regard du manque de caractĂšres diagnostiques de lâensemble de ses syntypes
Statut nomenclatural de Palaeothrissum inaequilobum Blainville, 1818, P. parvum Blainville, 1818, et Aeduella blainvillei (Agassiz, 1833) (Aeduelliformes, Aeduellidae)
It is shown that the species names Palaeothrissum inaequilobum Blainville, 1818, and P. parvum Blainville, 1818, from the Lower Permian (Asselian) of Muse, near Autun (SaÎne-et-Loire department, France) are senior synonyms of the widely used species name, Aeduella blainvillei (Agassiz, 1833). In the interest of nomenclatural stability, conditions exist which allow reversal of precedence as stated in Article 23.9.1 of the International Code of Zoological Nomenclature. Thus the species name Aeduella blainvillei (Agassiz, 1833) is regarded as valid, qualifying as a nomen protectum, whereas Palaeothrissum inaequilobum Blainville, 1818, and P. parvum Blainville, 1818, are invalid, qualifying as nomina oblita. Some of the specimens from the type series upon which P. inaequilobum, P. parvum and Aeduella blainvillei were erected, are identified.Il est montré que les noms spécifiques Palaeothrissum inaequilobum Blainville, 1818, et P. parvum Blainville, 1818, du Permien inférieur (Assélien) de Muse, prÚs d'Autun (SaÎne-et-Loire, France) sont des synonymes plus anciens de l'espÚce largement utilisée, Aeduella blainvillei (Agassiz, 1833). Afin de maintenir la stabilité nomenclaturale, les conditions sont cependant réunies pour une inversion de préséance en accord avec l'article 23.9.1 du Code International de Nomenclature Zoologique. Le nom spécifique Aeduella blainvillei est ainsi considéré comme valide et est qualifié de nomen protectum, alors que Palaeothrissum inaequilobum Blainville, 1818, et P. parvum Blainville, 1818, sont invalides et qualifiés de nomina oblita. Quelques specimens des séries types sur lesquelles furent créées les espÚces P. inaequilobum, P. parvum et Aeduella blainvillei, sont identifiés
Les «âichtyolitesâ» (Actinopterygii) de la collection Jean-Baptiste Beurard (1745â1835)â: intĂ©rĂȘt historique et redĂ©couverte de la sĂ©rie type dâ
Cet article souligne le rĂŽle Jean-Baptiste Beurard dans lâhistoire de la palĂ©oichtyologie. Ancien chanoine de la cathĂ©drale de Toul, il trouva aprĂšs les affres des dĂ©buts de la RĂ©volution un emploi dâagent du gouvernement attachĂ© Ă lâadministration des mines entre 1794 et 1815. ChargĂ© de la surveillance des mines de mercure dans les nouveaux dĂ©partements annexĂ©s par la France sur la rive gauche du Rhin, il redĂ©couvrit en juillet 1799 le fameux gisement dâ«âichtyolitesâ» (poissons fossiles) imprĂ©gnĂ©s de cinabre de MĂŒnsterappel datĂ© du Permien infĂ©rieur. Il envoya plusieurs spĂ©cimens dans des collections institutionnelles parisiennes. Des reprĂ©sentants de lâespĂšce Paramblypterus duvernoy (Agassiz, 183
Nouvelles données historiques sur les premiers dinosaures trouvés en France
Cet article passe en revue les premiĂšres dĂ©couvertes de dinosaures faites en France avant que le terme Dinosauria nâait Ă©tĂ© introduit par Richard Owen en 1842. En mettant Ă part les premiĂšres dĂ©couvertes du thĂ©ropode Streptospondylus altdorfensis faites au XVII
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