Print ISSN: 0031-0247
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Werneburg et al. New Permian Caseid from France
Embrithopod from Croatia
Field trip guides/EAVP Annual Conference/2023
Early Oligocene Fishes from Alabama, USA
Two enigmatic rodents from Lavergne (MP 16), Quercy Phosphorites
Eocene (57) , Quercy phosphorites (37) , Systematics (32) , Rodents (29) , Mammalia (26)
Norselaspis glacialis n.g., n.sp, et les relations phylogénétiques entre les kiaeraspidiens (Osteostraci) du dévonien inférieur du Spitsberg.Philippe JanvierKeywords: Devonian; kiaeraspids; Osteostraci; SpitsbergenAbstract The anatomy of Norselaspis glacialis n.g., n.sp., a primitive kiaeraspidian from the Lower Devonian of Spitsbergen, is described on the basis of spécimens studied by grinding sections or prepared with dilute formic acid. This study yielded some new anatomical details, including the presence of a canal prolonging posteromedially the canal alloted to the facial nerve by Stensiö. This posterior prolongation of the « facial canal ›› into the posterolateral part of the labyrinth cavity is consistent with the hypothesis put forward by Allis, Lindström, Jefferies and Whiting, that this canal housed the glossopharyngeus nerve. Furthermore, in N. glacialis, the foramen usually referred to as the foramen for the œsophagus opens posteriorly into a cavity in the postbranchial wall, referred to here as the intramural cavity, and which is interpreted as having housed the heart. Consequently, the œsophagus probably accompanied the dorsal aorta through the aortic canal. Finally, the foramen generally interpreted as having transmitted the ventral afferent arterial trunk is here considered as having housed the hepatic vein, which emptied into the venous sinus of the heart. The ventral afferent arterial trunk may thus have passed through the former «œsophageal ›› foramen. Article infos Published in Vol. 11, Fasc. 2-3 (1981) |
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