The locality of Montredon has provided 8 species of camivores, often little documented, that are discribed and depicted. All the remains are fragmentary and generally badly preserved which lowers very much the possible precision of the taxonomic study; this one has however allowed the creation of a new subspecies. The most richlypdocumented forms are an ursid (Indarctos) and a felid (Machairodus). Issuing often from a westem Europe evolution, the carnivores are well inserted between those of the better known faunas of the "Classical Pontian" and of the lower Vallesian and this situation fits also well with their stratigraphic level, that cannot however be more accurately defined with them alone.
  

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.
[...] 

Tetraceratops insignis is known from a single, crushed skull from the Lower Permian of Texas. Its unique proportions and osteological details gained central meaning in the question of the origins of Therapsida since this early synapsid has been determined as the oldest and less derived therapsid. Apart from Tetraceratops, the ‘mammal-like’ Therapsida and their sister, the pelycosaur-grade Sphenacodontidae, are separated by one of the longest ghost lineages in tetrapod fossil record. However, the minor, though well justified critique faced insistent publication regarding the therapsid hypothesis. A carefull re-evaluation of the holotypic skull reveals that therapsid traits cannot be supported, including a rejection of the formerly supposed adductor shelf in the temporal fenestra. Increased understanding of ‘pelycosaur’ character variation underlines a haptodontine-grade or, less likely, sphenacodontid position for Tetraceratops. 

The recently discovered, very rich, Pliocene locality of Layna (Soria, Spain), has already yielded 30 species of mammals. Hipparion fissurae, described here is more dolichopodic than other Hipparion. It is related to Hipparion crusafonti from Villaroya (Villafranchian), but more slender between other characters.
  

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.
  

A fossil species of the extant genus Leuconoe, L. lavocati n. sp. from Le Garouillas Oligocene locality, Quercy phosphorites, SW-France, is established in nomenclatural standards. 

The utilization of screen-washing and attack by dilute acetic acid has permitted the collecting, in the Miocene of the department of Hérault (France), of a very rich ichthyofauna. This fauna is presently comprised of about 60 studied species, of which 11 are new, and represents, in the present state of knowledge, the most varied Miocene selachian fauna described in the world.
The abondance of material has allowed an overall revision to be made; it has thus been possible to complete the description and the figuration of species that were poorly known until now, and to synonymize species that were established on simple morphotypes. Paleo-ecologic study of the ichthyofauna has permitted conclusions to be drawn relative to climate and bathymetry; it was thus possible to show that the Miocene fauna of Hérault was a fauna of a subtropical sea, essentially neritic with rare pelagic contributions.
Knowing the stratigraphic position of the localities, it has been possible to distinguish three faunal assemblages based on associations of species. Some hypotheses on the evolution of certain lineages have been expressed.
The comparison of this fauna with that of other regions permitted the relationships of two diflerent faunal provinces to be specified: the first belongs to the northern domain, characterized by a fauna still subtropical but with numerous temperate water elements; the leoond belongs to the Mesogean domain characterized by warm water forms. It has also lhovm that contemporary faunas could be very different according to the bathymetric zone in which they lived, which furnishes valuable information for the paleogeographic reconstruction of sedimentary basins.
  

The remains of Ruminantia are very rare at Montredon. No specific determination was possible. We have only one Micromeryx, one small cervid, one tragocere and one (?) gazella. The faunal spectrum is in good correlation with the general retreat of the cervids in the European upper Miocene, but in contrast it is not convenient for the bovids, which are in expansion at the same time. For them, we have to invoke the local ecological conditions.
  

The study of three new populations of Plesiosminthuspromyarion from the "phosphorites du Quercy" and of material from "Auvergne" brings new data on european oligocene Dipodidae. They appear in Western Europe at the beginning of late Oligocene. Evolutionary trends of the group are drawn and particularly the emergence of morphotypes announcing P. schaubi, from the Coderet level, is revealed among the most recent populations of P. promyarion. Differences are attempted to be drawn between the three species : P. promyarion, P. myarion and P. schaubi by restudying the type-population of P. myarion from the aquitanian deposits of Chavroches (Allier) in comparison with two other populations from the same age and the same region. Relationships between early european, american and asiatic Dipodidae are discussed. 

We report the first confirmed fossil bats from North Dakota, including a new species referable to the Vespertilionidae represented by a maxilla with P4-M3 from the Brule Formation, Fitterer Ranch local fauna, early Oligocene, Whitneyan North American Land Mammal Age. Unassociated postcranial fragments of the humerus and femur also represent a vespertilionoid, but appear to reflect a different, unidentified species. The new taxon, Quinetia frigidaria sp. nov., is referred to the genus Quinetia, previously known only from approximately contemporaneous deposits in Europe. The new species is larger than Quinetia misonnei from the early Oligocene of Belgium. It is similar in some morphological characters to Chadronycteris rabenae (Chiroptera incertae sedis) of the late Eocene (Chadronian) of northwestern Nebraska and to Stehlinia species (?Palaeochiropterygidae) from the Eocene and Oligocene of Europe, but differs from each in morphological details of the dentition and maxilla. An unassociated talonid of a lower molar from Fitterer Ranch shows myotodont morphology, unlike the nyctalodont lower molars in Q. misonnei, and thus represents a second chiropteran taxon in the fauna. Quinetia frigidaria is a member of a Paleogene radiation of bats near the low point of the Eocene-early Oligocene decline in global temperatures, increased seasonal aridity, and loss of tropical floras from mid-latitude North America. 

Study of pantolestid mammals from the late Ypresian locality of Prémontré (reference level MP 10) allows the recognition of three genera: Palaeosinopa. Pantolestes and Premontrelestes n. gen. Pantolestes, up to now only recorded from North America, is represented by P. sabatieri n. sp. Premontrelestes n. gen., represented by the type species P. duchaussoisi n. sp., is compared with Pantolestes and Buxolestes. The latter, known from middle Eocene sites in Europe, has not been recognized at Prémontré. Two other taxa, the first of which is close to Pantolestes and the second of Premontrelestes n. gen. are left in open nomenclature.    

Abstract not available 

The Zanclian marls from Papiol provided otoliths belonging to 53 teleost taxa; nine of those are new for the Mediterranean Pliocene. The association reflects a bathymetry between 150 and 350 m, but it is likely that such depths only existed at the initial stage of flooding of the Llobregat bay. A compilation of the available data for the whole Mediterranean realm at Zanclian time provided a list of 163 taxa, of which 105 could be identified at species level. This last group provides the most useful data for evaluating the composition and affinities of the Mediterranean Zanclian fauna, which appears to be significantly different from the Recent Mediterranean fauna. The Zanclian fauna counts 68 % of Recent species: 12,5 % were already represented in the Mediterranean Miocene, 37 % appeared there at the Zanclian, and 18 % are extra-Mediterranean today. This last group is essentially composed by oceanic fishes, living in the warm parts of the Atlantic and Indo-Pacific Oceans. It is evident that a non neglectable number of Recent species only penetrated very recently in the Mediterranean, which stresses the differences between the more oceanic Zanclian Mediterranean fauna and the present one.


  

Abundant crocodilian fossil remains have been collected, mainly by R. Lavocat. from several levels of the
Palaeogene of the Tilemsi valley (eastern Mali). Several dyrosaurids occur in the Palaeocene (Montian ?) : Phosphatosaurus sp., Hyposaurus bequaerti (Dollo). H. wilsoni (Swinton). H. nopesai (Swinton), Rhabdognathus rarus Swinton, R. compressus n. sp. ln the lower Eocene has been found a dyrosaurid which cannot be accurutely determined.In the middle Eocene were found a dyrosaurid, Tilemsisuchus lavocati n. g., n. sp., and an indeterminate eusuchian. 

A well-preserved anterior cranium of Paranourosorex gigas RZEBIK-KOWALSKA, 1975 from Podlesice, Poland, provides additional knowledge of this rare shrew, including almost complete maxillary dentition. The systematic status of this species as a relative of recent Anourosorex MILNE-
EDWARDS, 1870 is confirmed 

The geomyoid genus Dikkomys is well represented in a sample from the Black Bear Quarry Il local fauna of Early Hemingfordian age in Bennett County, South Dakota. Isolated unworn P/4's of Dikkomys matthewi WOOD have a prominent median cristid (sagicristid) with a connection to the metaconid and the hypolophid. With wear, P/4 does not become as molariform as P/4 because of this cristid.
A large sample of the Whitneyan beteromyid Proheteromys nebraskensis WOOD contains variants of the P/4 with on incipient sagicristid in approximately 18 percent of the population. The upper dentition and lower molars of Proheteromys nebraskensis are sufficiently generalized to indicate probable ancestry to Dikkomys. 

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 comparative morphology and biometry of the lower cheek teeth of modern Equus are studied on approximately 300 mandibles belonging to the 10 usually recognised species : Equus grevyi, E. burchelli, E. quagga, E. zebra, E. africanus, E. asinus, E. hemionus, E. klang, E. przewalskii, E. caballus. The studied parameters comprise : occlusal length and width, postflexid length and index ; shape of the double knot (metaconid + metastylid + lingual groove) ; depth of the vestibular groove on the molars ; frequency of the pli caballinid, protostylid and other enamel plications or islets ; frequency of the dP/l.
The same methods of study are applied to a number of North American, Eurasian and African species. For the sake of comparison, some Hemphillian equids were observed (Dinohippus interpolatus, Dinohippus leidyanus, Astrohippus ansae, Phiohippus mexicanus) but most of the discussed material belongs to Pliocene or Pleistocene species of Equus : the « stenonine ›› E. stenonis, E. simplicidens, E. sanmeniensis and E. teilhardi; the « caballine ›› E. scotti, E. lambei, E. Iaurentius, E. mosbachensis, E. germanicus, E. gallicus, E. taubachensis and the Liakhov horse. The relationships of other species, in particular the North American E. calobatus, E. occidentalis, E. cf mexicanus are not clear for the moment. ln Africa, the Plio-Pleistocene species from Koobi Fora (Kenya) show some stenonine and perhaps asinine affinities. The relationships of E. numidicus and E. tabeti are uncertain but these species are probably related to the East African ones. E. mauritanicus is most certainly related to the Quagga group.
The biometrical data are gathered in 32 tables ; 4 photographie plates and 19 figures illustrate the next. The whole is a complement of the previously published studies of the skulls, upper cheek teeth, incisors and metapodials of modern and fossil Equus.

  

The dentitions as well as one complete and several partial skeletons of Equoids from the Eocene lignite beds of the Geiseltal locality are revised. Instead of 13 species distinguished up to now 3 chronoclines with 5 species and 3 separate species are recognized (text. fig. 1). Propalaeotherium hassiacum HAUPT, 1925 is evolving into Propalaeotherium isselanum (CUVIER, 1824) between the levels of the « obere Unterkohle ›› and the « untere Mittelkohle ›› of the Geiseltal section. Propalaeotherium argentonicum GERVAIS, 1849 is shown to be present in the « untere Unterkohle ››, whereas Lophiotherium pygmaeum (DEPERET,1901) occurs in the « obere Mittelkohle ›› and in the « oberes Hauptmittel ››. Plagiolophus cartieri STEHLIN, 1904 appears during the transition from the « Mittelkohle ›› into the « Oberkohle ›› as the earliest true Palaeothere. Therefore the « Oberkohle ›› is already regarded as Upper Eocene. This is corroborated by the occurrence of a phyletic descendant of Propalaeatherium parvulum (Propalaeotherium n.sp.) in the middle and upper "Oberkohle " because this species appears otherwise for the first time at the mammal level of Lissieu. On the other hand Propachynolophus gaudryz (LEMOINE, 1878) described by Matthes (1977) from the « untere Unterkohle ›› turns out te be in fact a Phenacodont. Thus the decisive argument for classifying the « untere Unterkohle ›› as Lower Eocene has to be dropped. Biostratigraphically the « Unterkohle ›› and the «Basishauptrnittel ›› correspond with the lower Middle Eocene (mammal level of Messel), whereas the «unteres Hauptmittel ›› and the « untere Mittelkohle ›› are equivalent to the middle part of the middle Eocene (mammal level of lssel), and the « obere Mittelkohle ›› together with the « oberes Hauptmittel ›› coincide with the upper Middle Eocene (mammal level of Bouxwiller). 

A classification should be both usable and useful,not too complex either in the amount of splitting or in the number of hierarchies involved, and not so simple as to give a false assurance of knowledge of relationships. Classifications are only possible because we do not have complete knowledge of the evolution of the organisms concerned because gaps in the record are necessary to allow the separation of the various taxa. Rodent classification is complicated by the large number of organisms involved and by the geat amount of parallelism that has taken place in the evolution of any and all features. If several independent features are characteristic of a certain taxon, should an effort be made to define the group on the basis of all the features, or should only one be selected as the determinant ? Unless the evolution of the several features was closely linked, the former solution will sooner or later lead to insurmountable problems.