Reigechimys octodontiformis gen. et sp. novo and R. plesiodon sp. novo are described. They represent the frrst record of the family Echimyidae for the Cerro Azul Formation (Huayquerian Age, Late Upper Miocene) at La Pampa Province, central Argentina. Both species have hypsodont cheek teeth with an eight-shaped occlusal design. This dental morphology represents a noticeable case of convergence to octodontids and indicates that these echimyids inhabited open environments. 

Equus caballus antunesi, nova subspecies, was a hypsodont, slender, and rather small horse (around 141cm at the withers), with narrow hooves and protocones longer on P3/-P4/ than on M1/-M2/. It does not fit in any of the different "types" of Pleistocene caballine horses previously recognized but may be related to the horse from the Acheulean of Solana del Zamborino.
Hypsodonty, small size, slenderness, narrow hooves are all characters that can easily be related to ecological conditions. Equus caballus antunesi was probably a horse adapted to rather dry and cold conditions and to a hard ground. It does not seem related at all to the North-European Equus caballus germanicus-gallicus group. 

The study of dental variations in Landenodon from Dormaal (early Eocene, Belgium) shows that only one
species is present in this locality : L. woutersi QUINET, 1968 (Condylarthra, Arctocyonidae, Arctocyoninae). A high morphological variability is described, especially concerning the metaconid of P/4, the paraconid of M/2, and some characters of M1/ which have been found to be independant of each other. This variability is discussed. 

Crocodilians are represented in the Upper Eocene of Sainte·Néboule (Lot) by an isolated parietal and a dorsal scute, bath from young individuals. They are refferred to Diplocynodon sp. Predators (mammals and birds) are probably responsible for the occurrence of remains of small crocodilians (belonging to the genera Allognathosuchus and Diplocynodon) in the phosphorltes of Quercy. 

Evidence of 350 Lower Cretaceous Dinosaur footprints is pointed out in El Bayadh area. Their preliminary study allow to distinguish four trackway assemblages which reveal vertebrate bipedal presence forms of tri-and tetradactylous Dinosauroïds (Assemblages 1-3) and quadrupidal Sauropoïd (Assemblage 4).

The analysis of their footprint biometric features will attribute the quadrupidal Sauropoïd form to Brontopodus ichnogenus which is weIl known in the Jurassic and Cretaceous periods. In retum and despite their age, the dinosauroïd forms were approached, temporarily, to Grallator and Eubrontes types.

The occurrence of the dinosaur traces (Theropoïd and Sauropoïd) constitutes, in the Lower Cretaceous, an important first step of the knowlege of the marshy Reptilian fauna which takes over, from the begining of the Secondary Era, a wide paleogeographie area on the Southem Tethyan margin. 

The Montredon local fauna yielded very rare bats, represented by damaged isolated teeth. Only a few documents are available for this period of the European Neogene. ln this poor state of knowledge, the material represents three undetermined species, a supposed molossid and two vespertilionids. 

Sieving and washing of about 700 kg of sediment from the miocene site at Montpeyroux produced otoliths of 34 teleost species, of which four still occur in the present day fauna or are near to extant species. Among the fossil species, eight are new : Ilisha lerichei, «genus Clupeidarum ›› orbiculatus, Dipulus mediterraneus, Morone cornuta, Chanda nelsoni, Pomadasys steurbauti, «genus Sciaenidarum ›› barthassadensis and Paraplagusia roseni. The fauna found is typical for a tropical or subtropical very littoral, probably even estuarine environment; it was living in a period near the boundary between Lower and Middle Miocene, perhaps somewhat earlier. 

L'exploitation des phosphates s'est produite surtout de 1890 à 1914 de Saint-Antonin à Cajarc, sur le Causse de Limogne, dont l'histoire géologique et morphologique peut expliquer les conditions de gisement du minerai, et aussi la découverte des nombreux, variés et beaux fossiles qu'on a extrait des poches en même temps que la phosphorite. Le Causse de Limogne est le nom donné par les géographes au plateau calcaire, faisant partie des Causses du Quercy, et compris entre la vallée du Lot au Nord et celle de "Aveyron au Sud". En fait, le nom de "causse" désigne localement un terroir, un paysage, à sous-sol de calcaire, à sol peu épais, qui s'oppose aux sols argileux des « terreforts » et aux sols légers et profonds des "boulbènes". Chaque communauté agricole distinguait ainsi son causse, par exemple le causse de Caylus, le causse de Limogne ou le causse de Cajarc. C'est par extension que l'appellation Causse de Limogne désigne tout un petit pays. La présence des poches à phosphate déborde un peu vers le Nord la vallée du Lot, et vers l'Est le Causse de Limogne proprement dit (Causse de Villeneuve).   

Abstract not available 

Abstract not available 

Two species lineages of North American late Paleocene Plesiadapis exhibit a pattern of size divergence from a common ancestral lineage. Time series of fossils in each of these lineages are analyzed to test the idea that size divergence represents competitive character displacement. The critical factor in a test of character divergence is showing that divergent lineages evolved directionally rather than randomly (multifactorially). Analysis of evolutionary rates and their temporal scaling in Plesiadapis shows that both divergent species lineages have the scaling slope expected for lineages evolving randomly rather than directionally, and size divergence in Plesíadapis does not represent character displacement. Rates of evolution commonly observed on a per-generation time scale are high enough to produce character displacement within a few generations. Thus character displacement is not likely to be visible on scales of time that can be studied in the fossil record. 

Editorial for celebrating the publication of the volume 20.

La revue PALEOVERTEBRATA a été fondée en 1967 par Louis THALER, à une époque où il n'existait, au plan international, que deux périodiques uniquement consacrés aux vertébrés fossiles. Actuellement ce nombre n'est que de quatre. A l'origine la revue fut essentiellement créée pour diffuser les résultats des chercheurs du Laboratoire de Paléontologie de l'Université de Montpellier, alors en début d'expansion et plusieurs thèses et de nombreux travaux directement liés à des thèses y furent publiés ce qui n'excluait déjà pas la publication d'articles d'auteurs étrangers.
[...] 

La découverte de nouveaux gisements à micromammifères dans le Miocène du Sud de la France et d'Espagne montre que, s'il n'est plus possible d'accepter dans son intégralité le schéma phylétique de Fahlbusch du genre Megacricetodon, il existe toutefois des segments de lignées à l'intérieur de provinces géographiques différentes (Péninsule Ibérique, France, Europe Centrale), avec lesquels on peut établir une biochronologie locale, segments qu'il est aussi possible de placer les uns par rapport aux autres, en utilisant les corrélations que l'on peut reconnaître entre certains niveaux repères des mammalogistes et l'échelle stratigraphique marine.
En utilisant ces données nouvelles, et d'après l'étude de la première molaire inférieure, nous proposons le
schéma évolutif suivant, pour les espèces de grande taille :

1 - au début du Burdigalien supérieur. une espèce commune, M. collongensis, issue de la forme ancestrale M. primitivus, est présente, de la Péninsule Ibérique à l'Europe Centrale. Son évolution est mal connue en Espagne, par contre cette lignée s'éteindrait en France au Burdigalien terminal avec le stade M. gersii nov. sp. de Sansan et de Luc-sur-Orbieu.
2 - au cours de la régression post-burdigalienne. reconnue en Languedoc et dans la Péninsule Ibérique apparaîtrait une espèce immigrante, M. crusafonti qui, dans cette dernière province, évolue pour donner M. ibericus de Nombrevilla. L'espèce M. gregarius de La Grive M et de La Grenatière dériverait de cette forme immigrants, en ayant une évolution différente.
3 - en Suisse, Bavière et Europe centrale, la lignée M. primitivus - M. collongensis va s'individualiser, dès le Burdigalien supérieur ou terminal, et donner naissance à la lignée M. bavaricus qui s'éteindra avec le stade M. germanicus nov. sp. du gisement anté - Hipparion de Anwil. Cette dernière espèce a été trouvée pour la première fois en France, dans le gisement de Collet Redon. 

The teeth and the astragale of the Creodonta from Ste-Néboule (Lot) are referred to Hyaenodon brachyrhynchus. Isolated teeth fit morphologically the material from La Débruge (Middle Ludian). However, biometric analysis suggests an Upper Ludian age. 

There are very few birds in the site of Sainte-Néboule. They belong to three species already known in the "Phosphorites" : Paraortyx brancoi, Aegialornis broweri, Cypselavus gallicus, and to one new species, Recurvirostra santaeneboulae. The comparison of some different bones of the genus Cypselavus with some Apodiformes and Caprimulgiformes shows that this genus must be classified in the order Apodiformes. 

The family Didelphidae is represented by three species in the Sainte-Néboule site, phosphorites of Quercy (lower Oligocene, San Cugat's nivel): Amphiperatherium minutum (Aymard), Amphiperatherium sp. and Peratherium cuvieri (Fischer). Only the first  and  third species are abundant (88 and 97 pieces). This two populations are described. The marsupial fauna of the european lower Oligocene is not recognized in its entirety in this site. 

Carolocoutoia ferigoloi gen. et sp. nov. is the largest of protodidelphid marsupials, known from Middle Paleocene levels at Itaboraí Formation, southeastern Brazil. It differs from other members of this family in having molars with low cusps which are basally inflated, rounded crests without cutting edges, and a thick enamel layer which is wrinkled, specially at the labial half. A comparative analysis among representatives of this family led us to recognize only three genera undoubtely assignable to it:  Protodidelphis PAULA COUTO, 1952, Robertbutleria MARSHALL, 1987, and Carolocoutoia gen. nov. Protodidelphids lack the basic derived features diagnostic of Polydolopimorphian marsupials, while most of its derived features agree with its belonging to the Didelphimorphia. Protodidelphids comprise a specialized clade of opossum-like marsupials adapted to frugivorous or frugivore-omnivorous feeding habits. They differ from other didelphimorphians in having very large, spire-like entoconids, reduced and antero-posteriorly compressed paraconids, absence of stylar cusp C and of para- and metaconules, large stylar cusps B and D which are proximate to each other, short postmetacristae, eccentric protocones, and molars that increase rapidly in size from M/ml to M/m3.
  

The general principles guiding the study of wear facets which develop during mastication in mammals possessing tribosphenic molars are named. The application of this method of study to the molars of European Tertiary Didelphidae shows that the lineage of this family as represented by the species Peratherium cuvieri (Upper Eocene), P. elegans (Lower-middle Oligocene) and P. antiquum (Upper Oligocene) has propessively evolved toward a more carnivorous diet. 

The composition of assemblages of lizards and Amphisbaenian from the European Eocene are described. At least ten lizard families are identified from the lower European Eocene levels. Eight are still recorded in the last level (Escamps) of the late Eocene. Agamid lizards (genus Tinosaurus) died out by the end of the lower Eocene and Varanid lizards (genus Saniwa) disappeared by the beginning of the late Eocene. Amphisbaenians are recorded throughout the Eocene in Europe. The lacertilian fossil record of Europe and North America show a high degree of faunal resemblance in the early Eocene, followed by a decrease during the later part of the epoch. The lacertilian and amphisbaenian faunas from the European Eocene are not subject to great variations during the period; this is in contrast with the mammal record at the same time. It is argued that the low metabolic rates and the ectothermy of lizards could explain those differences, along with the increasing insularity of the West European area during the late Eocene time.

  

L'ouvrage est divisé en trois grandes parties traitant successivement: I. l'anatomie ("Proboscidean flesh and bones"), en abordant la taxonomie, l'allure générale et l'éco-éthologie des proboscidiens actuels et fossiles; II. les causes de mortalité collective naturelle et provoquée chez les actuels; III. les documents fossiles et l'extinction des formes anciennes d'Amérique du Nord.