Print ISSN: 0031-0247
Online ISSN: 2274-0333
Révision des Rhombodontidae (Neoselachii Batomorphii) des bassins à phosphate du Maroc
Evolution et extinction des reptiles marins au Mésozoïque
Les oiseaux aquatiques (Gaviiformes à Anseriformes) de Saint-Gerand-le-Puy. Révision systématique.
Les traces de pas de Dinosaures et autres Archosaures du Lias inférieur des grands Causses, Sud de la France
La palichnofaune de vertébrés tétrapodes du permien supérieur du Bassin de Lodève .
Multituberculate endocranial castsAllotheria; Cretaceous; endocranial cast; Mongolia; multituberculates
A reconstruction of a multituberculate endocranial cast is made on the basis of a complete natural cast prepared from the skull of Chulsanbaatar vulgaris, and other less complete endocasts, all from the Late Cretaceous of Mongolia. The multituberculate endocast is of mammalian pattern but it has retained a therapsid-like lateral profile with a deep rhombencephalon and a shallow telencephalon. It is characterized by: a heart-shaped cross-section of the telencephalon; an extensive lissencephalic neocortex; a very prominent pons placed far anteriorly; a lack of cerebellar hemispheres, and very large paraﬂocculi. Its structure, very different from the brains of other mammals, suggests thats the Multituberculata branched very early from the main mammalian stock. This supports Simpson's (1945) idea that the Multituberculata should be placed in a subclass of their own: Allotheria MARSH. The endocast and braincase structure show that the Multituberculata had strongly developed senses of smell and hearing. The encephalization quotient of approx. 0.55 evaluated for Ch. vulgaris is relatively high for a Mesozoic mammal.
Published in Vol. 13, Fasc. 1-2 (1983)