Etude sur les vertébrés inférieurs (VIIe Symposium International, Parc de Miguasha, Québec, 9-22 Juin 1991), édité par Marius ARSENAULT, Hervé LELlÈVRE & Philippe JANVIER, 1994. Bulletin du Muséum National d'Histoire Naturelle, Paris, 4e Série, T. 17, Section C, n° 1-4, 529 p.

Ce volume spécial du Bulletin du Muséum réunit les actes du congrès international sur les Vertébrés inférieurs qui s'est tenu au Québec en 1991. 

The fauna from three new rodent localities (Castelmaurou, Grépiac-carrière et Grépiac-rive gauche) from Oligo-Miocene molasses of the Toulouse area is described. The one from Colomiers is completed. 11 species belonging to 4 families (Cricetidae, Eomyidae, Gliridae, Sciuridae) are present. The Miocene localities of Grépiac-carrière and Colomiers are correlated with Balizac, La Brète, Lambert and Lespignan. Grépiac-rive gauche is just a little older than these sites. Castelmaurou is somewhat younger than La Milloque and belongs to Oligocene. 

Cranial anatomy of a late Miocene rhizomyid, Brafhyrhizomys cf. B. pilgrimi, provides new evidence on the origin of the dorsal, round infraorbital foramen of living rhizomyines. Primitive rhizomyids retain a myomorphous keyhole foramen with a long ventral slit that retracts upward during the evolutionary history of the Rhizomyidae. The primitive condition of the elongated ventral slit is represented by Kanisamys sivalensis. Among later burrowers the foramen shows progressive dorsal migration, the ventral slit terminating midway up the snout in B.tertracharax and B. choristos ; well above the midline of the snout in Brachyrhizamys cf. B. pilgrimi. Apparently this transformation began earlier among Rhizomyinae than among Tachyoryctinae and continued to a more derived stage in rhizomyines. ln living Rhizomyx the ventral slit is absent and only a high round hole remains at the anterior end of the zygomatic arch. 

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. 

The study of that locality allowed the description of a new Muridae : Paraethomys athmeniae n. sp. It reveals the existence of new rodent for Algeria : first, a Sciuridae, Atlantoxerus cf. rhodius, and second, a Gliridae, Eliomys truci. So, that work shows the presence of the genus Eliomys in North Africa before the middle of Pleistocene. Lastly, Paraethomys cf. anomalus gives an exact datation of that bed. 

The Montian locality of Hainin (Hainaut, Belgium) yielded about twenty teeth of Multituberculates. They are very peculiar forms, showing no affinities, at the generic level, with those hitherto known from North America, Asia and Europe. They are referred to the new taxa Boffius splendidus nov. gen., nov. sp., Hainina belgica nov. gen., nov. sp., and H. godfriauxi nov. gen., nov. sp. They expose some common features, such as the advanced type of first upper molar. possessing at least three complete rows of cusps. Because of this, and also of the upper premolar reduction, Boffius splendidus appears as the most specialized form within the Ptilodontoidea suborder.
Several other characters of Hainina seem to be less advanced, such as the great number of upper premolars and the simple cusp-formula of the first lower molar.
Till now, only H. godfriauxi has been recovered within the Thanetian fauna from Cemay-les-Reims, where it is very poorly documented. 

The fossil mammals collected from the Eocene of Hammada du Dra (northwest Sahara. Algeria) and two fragmentary teeth from the Lutetian of M'Bodione Dadere (Senegal) are described.
The fossils from the northwest Sahara come from a lacustrian deposit dated by charophytes (Raskyella aff. pecki, Raskyella n. sp.. Maedleriella lavocati, Maedleriella sp. et ? Peckichara sp.) as Middle Eocene or perhaps Lower Eocene (Gevin, Feist and Mongereau, 1974). Several hyracoids (3 or 4) identified from this formation extends the age of the family Pliohyracidae Osborn in Africa. Three forms appear to belong in the genera Megalohyrax, Titanohyrax and perhaps Bunohyrax which have been know until now only from the lower Oligocene of the Fayum (M. gevini n. sp. ; T. mongereaui n. sp.. ? Bunohyrax or Megalohyrax indet.). Another hyracoidof small size is referred to a new genus, Microhyrax (M. lavocati n. sp.).
Helioseus insolitus n. g. n. sp. is described without ordinal assignment. Azibius (Sudre, 1975) which has been the subject of questions and interpretations is reviewed.
Only one tooth from the Lutetian of M'Bodione Dadere is complete enough to interpret. lt probably belongs to a condylarth and demonstrates for the first time, the presence of the order in Africa. The second tooth is too fragmentary for comment.
In conclusion., the paleobiogeographic role of Africa at the end of the cretaceous and the beginning of the Cenozoic is discussed. 

Two new Squalicorax species, S. benguerirensis nov. sp. and S. microserratus nov. sp. are described from the Lower Maastrichtian of the Benguérir phosphate open mine, Ganntour deposit, Morocco. The species S. benguerirensis nov. sp. was classically assigned to S. yangaensis since Arambourg (1952) and has been also recognized in coeval deposits from eastern USA to Mid-East. The species S. microserratus nov. sp. correspond to the lateral teeth of S. kaupi as reported by Arambourg (1952) and which is now referred in fact to S. bassanii. The comparison of these two new species with other Anacoracids, known in Moroccan or elsewhere, allows highlighting the great taxonomic and ecological diversities of this family during the Cretaceous.
  

A recent campaign of excavations (1965-68) undertaken by the Laboratoire de Paléontologie of Montpellier in pockets of the Quercy phosphorites, has permitted the dating of several localities thanks to the analysis of their micromammalian fauna.
The rodents of localities belonging to the middle Oligocene (La Sauvetat zone) are the object of this study. This rodent fauna has been compared to the forms coming from three stratified localities belonging to the biochronologic zone of La Sauvetat :  Balm, Montalban and Lovagny.
The abundance of material, notably of theridomyids and cricetids, permitted a summary statistical study to be effected and gave some precise details on the variability of the species (Theridomys varians in particular). Other details were provided on certain groups, notably on the upper teeth of Scíuromys cayluxi and on the milk teeth of theridomyids. Some specimens of «Sciurus» sp. and of Plesispermophilus angustidens were collected. By this means, it has been possible to establish, for the first time, a precise upper limit to the epoch of their appearance in Europe. 

Micro-CT imaging is an increasingly popular method in paleontology giving access to internal structures with a high resolution and without destroying precious specimens. However, its potential for the study of hypoplasia defects has only recently been investigated. Here, we propose a preliminary study to test whether hypoplastic defects can be detected with micro-CT (μCT) scan and we assess the costs and benefits of using this method instead of naked eye. To do so, we studied 13 fossil rhinocerotid teeth bearing hypoplasia from Béon 1 (late early Miocene, Southwestern France) as positive control and 11 teeth of the amynodontid Cadurcotherium (Oligocene, Phosphorites du Quercy, Southwestern France), for which enamel was partly or totally obscured by cement. We showed that all macroscopically-spotted defects were retrieved on 3D reconstructions and selected virtual slices. We also detected additional defects using μCT scan compared to naked eye identification. The number of defects detected using μCT was greater in the Cadurcotherium dataset (paired-sample Wilcoxon test, p-value = 0.02724) but not for our control sample (paired-sample Wilcoxon test, p-value = 0.1171). Moreover, it allowed for measuring width and depth of the defects on virtual slices (sometimes linked to stress duration and severity, respectively), which we could not do macroscopically. As μCT imaging is both expensive and time consuming while not drastically improving the results, we recommend a moderate and thoughtful use of this method for hypoplasia investigations, restricted for instance to teeth for which enamel surface is obscured (presence of cement, uncomplete preparation, or unerupted germs). 

Abstract: A very tiny cuckoo, Chambicuculus pusillus, was recently described after a few fragments of tarsometatarsi from the late Early/early Middle Eocene of Djebel Chambi, Tunisia. New remains, notably a coracoid, confirm the attribution of this genus to the recent family Cuculidae. This coracoid shows a very elongate and strap-like processus procoracoideus. This morphological feature is otherwise only known in the family Cuculidae. The characteristics of the coracoid and tarsometatarsi show that Chambicuculus is morphologically more advanced over the other stem cuculids described in Europe and North America. Chambicuculus is the oldest Cuculidae known so far. 

The Squamates from Sainte-Néboule are charateristic of the Upper Eocene from the Phosphorites du Quercy. Most genera known from this locality do not survive the « Grande Coupure ». Cadurcoboa insolita gen. nov., sp. nov. is a small Boidae very characteristic of the Upper Eocene. 

The wear facets of primitive rodents can be homologized with those of primitive primates and ungulates. As in primates, the jaw movement was ectental, with an increased anterior component in the lingual phase (phase ll). The buccal phase (phase I) in rodents approaches the horizontal and it tends to be reduced in importance in comparison with the lingual phase. ln more advanced rodents the efficiency of grinding is increased by the development of additional cutting edges of enamel (e.g. enlargement of hypocone, development of mesoloph and lingual sinus). The buccal phase movement becomes lined up with the lingual phase movement to form a single oblique chewing stroke,resulting in planation of the crown. As the stroke becomes more longitudinal (propalinal) the enamel edges become more transverse. In Muridae propalinal chewing evolved before the loss of cusps, facets were reorientated and additional cusps developed. 

The study of another faunal assemblage (mostly macromammals) from Torralba de Ribota (Calatayud, Zara-
goza Prov.) demonstrates the Middle "Burdigalian" age of the deposit, MEIN zone 4a. Some ten genera have been recognized. a.o. Anchitherium, Aceratherium and Lagopsis. 

New dental and skeletal material referable to Palaeochiropteryx tupaiodon from the Middle Eocene locality of
Messel (G.F.R.) is studied, which provides additions to the previously gained knowledge of this european genus. Dental specimens from Geiseltal (G.D.R.), also of Middle Eocene age, allow us to analyze Cecilionycteria prisca. Some of these are separated to establish a new genus, Matthesia, and two new species, M. germanica and M. ? insolita. 

Mammal-bearing localities have been discovered in the marine and lacustrine series of the middle Ilerdian (Lowermost Eocene) from Southem France (Minervois and Corbières). In the localities of Fordones, Monze, Fournès, and La Gasque, thirty mammal species have been identified. Among others, they include ischyromyid rodents (Microparamys and Pseudoparamys), paromomyid and adapid primates (Arcius and Donrussellia), new insectivores, condylarths, and a dyspternine pantolestid. These faunas provide new informations on the early Eocene Mesogean faunas of Rians and Palette. The assemblages of primates and rodents from Fordones support good  correlations with Palette which was recently placed near the standard-level of Dormaal (MP 7). In fact, Palette and Fordones could be even older than Dormaal. Consequently, there seems to be a relatively important temporal gap between the late Paleocene of Cernay and the Sparnacian of Dormaal. This gap could be partly filled with the Mesogean faunas of Palette, Fordones, and Silveirinha. On the basis of these new mammal faunas the marine middle Ilerdian is proved to be older than the Cuisian stage of the Paris Basin. With regards to the position of the Fordones fauna at the top of the NP 10 calcareous nannoplankton biozone, the westem European paleomammalogists Paleocene/Eocene boundary could be situated between the NP 9 and NP 10 biozones. 

Four new taxa (two genera, one subgenus, and four species) conceming the orders Condylarthra, Rodentia, Pantolesta, and an undetermined order from middle and middle/upper Ilerdian localities (lower Ypresian) of the Corbières and Minervois regions (Bas-Languedoc, Southem France) are presented in this short paper 

Palaeotis weigelti, from the Middle Eocene of central Europe, is a flightless, paleognathous bird. It appears to be a member of the ostrich lineage on the basis of trivial derived characters. It is a very primitive ratite, however, and does not possess any of the highly specialized cursorial adaptations that characterize the modern steppe -and savanna- dwelling ostriches. 

The Mont-Hélène's fauna [Pyrénées-Orientales, France], includes 15 species of rodents with a new one, Occitanomys montheleni n. sp. among the 9 species of the Murids which are listed. The uncommon Cricetid, Blancomys neglectus, is well represented in the fauna. Peculiarities of the population referred to Slephanomys cf. donnezaniare discussed. The locality a fissure filling may be the oldest one of Tabianian age known in Southern France. The diversity of the Murids gives evidence of a subtropical climate and of a diversified environment which may be linked to the spreading of the coastal plain following the filling up of the Roussillon Neogene Basin. 

The dentition of selachians is characterized by an often very pronounced heterodonty involving a great morphological diversity. Despite this fact, the dentitions of selachians can be grouped in a rather reduced number of dental types corresponding to trophic adaptations: grasping, tearing, cutting, crushing, grinding and grasping-grinding type. The numerous exemples of convergence and parallelism that can be observed in fossil selachians and between Recent and fossil ones is the result of this reduced number of dental types. These dental specialisations allow to try a reconstruction of the way of life of fossil forms.