Print ISSN: 0031-0247
Online ISSN: 2274-0333
Révision des Rhombodontidae (Neoselachii Batomorphii) des bassins à phosphate du Maroc
Les traces de pas d'amphibiens, de dinosaures et autres reptiles du Mesozoïque Français
About the genus Propachynolophus Lemoine 1891
La palichnofaune de vertébrés tétrapodes du permien supérieur du Bassin de Lodève .
A pangolin from the French Quercy phosphorites
Norselaspis glacialis n.g., n.sp, et les relations phylogénétiques entre les kiaeraspidiens (Osteostraci) du dévonien inférieur du Spitsberg.Devonian; kiaeraspids; Osteostraci; Spitsbergen
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.
Published in Vol. 11, Fasc. 2-3 (1981)