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A fossil feather preserved as a carbonised trace is described from the Tomaj Limestone at Križ, in the Kras region of southwestern Slovenia. The Tomaj Limestone is a platy and laminated limestone with cherts, which occurs within a well-bedded rudist limestone of the Santonian–Campanian Lipica Formation. It was deposited in a lagoon environment and has yielded a diverse fossil assemblage. Whether this feather belonged to a bird or to a dinosaur is unclear, but it is an addition to the scanty record of Late Cretaceous feathers, from a palaeobiogeographically interesting area.

A new genus and species of primitive cryptodiran turtle, Siamochelys peninsularis n. g. n. sp., from the Middle Jurassic Mab Ching locality, in the southern peninsula of Thailand, is described on the basis of complete shells. They are characterized by a combination of primitive features (the presence of a pair of mesoplastra meeting on the midline) and a series of derived characters (loose plastron–carapace attachment, short diamond-shaped entoplastron, dorsal thickening of the lateral edge of the second to seventh peripheral plates, expanded seventh to eleventh peripheral plates, extension of the anal scute to the hyo-hypoplastral suture or onto the hypoplastron, midline sulcus sinusoidal), and thus closely resemble Chengyuchelys, from the Middle Jurassic of China, and more particularly Xinjiangchelys and its relatives from the Middle and Late Jurassic of China and Central Asia. This supports a Middle Jurassic age for the locality and suggests that the Sibumasu (Shan-Thai) block was in contact with the Asian mainland by that time.

A newly discovered incomplete dinosaur dentary from the Chenini Sandstones (early Albian) of Jebel Miteur (Tataouine Governorate, southern Tunisia) is extremely similar to the corresponding part of the type of Spinosaurus aegyptiacus STROMER, 1915, and is identified as Spinosaurus cf. aegyptiacus. A review of African spinosaurids shows that baryonychines were present in the Aptian, and apparently became replaced by spinosaurines in the Albian and Cenomanian, perhaps as part of a more general faunal change between the Aptian and Albian. Spinosaurines may have been derived from the less advanced baryonychines. Several alternative hypotheses about the biogeographical history of the Spinosauridae are discussed.

Newly discovered sauropod material from the Upper Triassic of northeastern Thailand reveals that some of the earliest sauropods had already reached a very large size. A 1 m long humerus is within the size range of large Jurassic sauropods such as Camarasaurus and suggests an animal reaching a length of 12 to 15 m. It took sauropodomorph dinosaurs some 20 million years to produce giant forms, a rapid size increase when compared with that observed in the evolution of other dinosaurs, such as ornithischians. To cite this article: E. Buffetaut et al., C. R. Palevol 1 (2002) 103–109.

International audience; The paralic flora and fauna from the Late Jurassic of Chassiron (Oléron Island, western France) are described. The Tithonian-aged bonebeds of Purbeck facies of this locality have yielded a rich and diverse vertebrate assemblage including fishes, amphibians, reptiles and mammals, alongside numerous plant and invertebrate remains. The Chassiron locality thus appears as a peculiar Konzentrat-Lagerstätte in which most of the palaeoecosystem's biological components (both aquatic and terrestrial) have been preserved. The depositional environment was probably subject to salinity fluctuations, as indicated by the co-occurrence of freshwater and euryhaline organisms. This is one of the richest localities and the first mammal-bearing site known from the Jurassic of France.

Three main groups of large flightless birds are known from the Palaeogene of Europe: Gastornithidae, Ratitae, and Phorusrhacidae. Gastornithids have the longest and most complete record (Selandian to middle Lutetian). Ratites have a patchy record (Thanetian and Lutetian). Phorusrhacids are known only from the late Lutetian. Gastornithids probably originated in Europe, whereas phorusrhacids probably reached Europe from Africa.

The mode of life of the early Tertiary giant bird Gastornis has long been a matter of controversy. Although it has often been reconstructed as an apex predator feeding on small mammals, according to other interpretations, it was in fact a large herbivore. To determine the diet of this bird, we analyze here the carbon isotope composition of the bone apatite from Gastornis and contemporaneous herbivorous mammals. Based on (13)C-enrichment measured between carbonate and diet of carnivorous and herbivorous modern birds, the carbonate δ(13)C values of Gastornis bone remains, recovered from four Paleocene and Eocene French localities, indicate that this bird fed on plants. This is confirmed by a morphofunctional study showing that the reconstructed jaw musculature of Gastornis was similar to that of living herbivorous birds and unlike that of carnivorous forms. The herbivorous Gastornis was the largest terrestrial tetrapod in the Paleocene biota of Europe, unlike the situation in North America and Asia, where Gastornis is first recorded in the early Eocene, and the largest Paleocene animals were herbivorous mammals. The structure of the Paleocene terrestrial ecosystems of Europe may have been similar to that of some large islands, notably Madagascar, prior to the arrival of humans.

The stratigraphic distribution of the three main groups of large flightless birds known from the Palaeogene of Europe, Gastornithidae, Phorusrhacidae and Ratitae, is reviewed. The huge, herbivorous gastornithids, represented by the single genus Gastornis , are known from the Selandian (Middle Palaeocene) to the late Lutetian (Middle Eocene), being recorded from reference levels MP5 to MP13. The carnivorous phorusrhacids are represented by a single species, Eleutherornis cotei , from the late Lutetian (MP14, late Middle Eocene). The ratites have a patchy distribution, being represented by two species of moderate size, Remiornis heberti from the Thanetian (MP6, Late Palaeocene) and Palaeotis weigelti from the Lutetian (MP11 to MP13, Middle Eocene). The stratigraphic distributions of large eggs referred to gastornithids in the Late Palaeocene and Early Eocene of southern Europe and the occurrence of enigmatic large avian footprints in the Late Eocene of France are discussed. Whereas gastornithids and ratites co-existed in both the Palaeocene and the Middle Eocene, phorusrhacids seem to have been the only large ground birds in Europe at the end of the Middle Eocene. The palaeobiogeographical and evolutionary implications of the stratigraphic distributions of those groups of large birds in Europe are discussed. As Gastornis first appears in North America and in Asia in the Early Eocene, it is likely that gastornithids originated in Europe and later spread to other land masses during a dispersal event close to the Palaeocene–Eocene boundary. Prior to that, gastornithids evolved on the European “island continent”, where they were the largest terrestrial tetrapods during the Palaeocene. Gastornithids do not seem to have been significantly affected by the PETM. Ratitae have a more patchy record and relationships between Remiornis and Palaeotis remain unclear. Nevertheless, those European forms are among the earliest known ratites and this should not be overlooked in discussions of ratite evolution and palaeobiogeography. Phorusrhacids appear to have been present in Europe for only a short time and are interpreted as the result of dispersal from Africa followed by local extinction.

In the early 1980s, the remains of a large crocodil- ian, consisting of a nearly complete lower jaw, were referred to a distinct species of Sunosuchus, S. thailandicus. The specimen was recovered from a road-cut near Nong Bua Lamphu, north-eastern Thailand, in the upper part of the continental Phu Kradung Formation, and then considered Early to Middle Jurassic in age. Since then, this age has been revised and most of the formation is now considered Early Cretaceous, although a Late Jurassic age is possible for its lowermost part. Here, we report for the first time cranial elements associated with man- dibular remains assignable to 'S'. thailandicus. An attribution to Pholidosauridae is proposed on the basis of premaxillary morphology, and the original referral of this taxon to the go- niopholidid Sunosuchus is discarded. A new genus name Chal- awan now designates the originally described material of S. thailandicus. Nevertheless, the newly described specimen shares a characteristic with both 'traditional' Goniopholididae and Pholidosauridae: the presence of a depression located on the lateral wall of the maxilla and jugal. A phylogenetic analy- sis confirms the inclusion of both Goniopholididae and Pho- lidosauridae into a common clade, Coelognathosuchia tax. nov. Although the new Thai skull is much fragmented, its original shape is reconstructed and is compared with other pholidosaurid genera, namely Elosuchus, Meridiosaurus, Oce- anosuchus, Pholidosaurus, Sarcosuchus and Terminonaris. The presence of the genus Sunosuchus being highly questionable in Thailand, it cannot be used as evidence to link the Chinese and Indochinese blocks. Instead, the recognition of a fresh- water pholidosaurid in a continental formation of the Indo- chinese block suggests that early in their evolutionary history, these crocodilians, already known from Europe, Africa and South America, were more widely distributed along the north- ern margin of the Tethys than previously recognized.

A long and slender wing metacarpal from the Late Oxfordian Sables de Glos of Cordebugle (Calvados, Normandy) clearly belongs to a pterodactyloid pterosaur, with an estimated wingspan of at least 2.30 m. This is currently one of the earliest records of a representative of the Pterodactyloidea.

Pterosaurs were hitherto represented in the abundant and varied Late Campanian–Early Maastrichtian vertebrate assemblages of southern France by very scanty remains, which did not allow an identification at the family level. An incomplete cervical vertebra from a locality of that age at Cruzy (Herault, southern France) is described and identified as belonging to an azhdarchid pterosaur with an estimated wingspan of about 3 m.

RICHARD T. J. MOODY1*, ERIC BUFFETAUT2, DARREN NAISH3 & DAVID M. MARTILL3 Faculty of Science, Kingston University, Penrhyn Road, Kingston KT1 2EE, UK Centre National de la Recherche Scientifique, UMR 8538, Laboratoire de Geologie de l’Ecole Normale Superieure, 24 rue Lhomond, 75231 Paris Cedex 05, France School of Earth & Environmental Sciences, Burnaby Building, Burnaby Road, University of Portsmouth, Portsmouth PO1 3QL, UK

BackgroundPhorusrhacidae was a clade including middle-sized to giant terrestrial carnivorous birds, known mainly from the Cenozoic of South America, but also occurring in the Plio-Pleistocene of North America and the Eocene of Africa. Previous reports of small phorusrhacids in the Paleogene of Europe have been dismissed as based on non-phorusrhacid material.Methodologywe have re-examined specimens of large terrestrial birds from the Eocene (late Lutetian) of France and Switzerland previously referred to gastornithids and ratites and have identified them as belonging to a phorusrhacid for which the name Eleutherornis cotei should be used.Conclusions/significanceThe occurrence of a phorusrhacid in the late Lutetian of Europe indicates that these flightless birds had a wider geographical distribution than previously recognized. The likeliest interpretation is that they dispersed from Africa, where the group is known in the Eocene, which implies crossing the Tethys Sea. The Early Tertiary distribution of phorusrhacids can be best explained by transoceanic dispersal, across both the South Atlantic and the Tethys.

A tibiotarsus of an archaic bird from the Upper Cretaceous of Fox-Amphoux (Var, southern France) is described and referred to the Enantiornithes. Taken together with other recent discoveries of Late Cretaceous birds from France, this find suggests that at the end of the Cretaceous, the European avifauna was dominated by archaic forms.

Remains of dinosaurs and other vertebrates (sharks, bony fishes, coelacanths, turtles, crocodilians, pterosaurs) are reported from the Chenini Formation of the Tataouine region in southern Tunisia. The Formation is part of the ‘continental intercalaire’, a succession of continental deposits of Early to Late Cretaceous age distributed over the whole of North Africa and the Sahara. It consists of bar and channel deposits of broad rivers that flowed NNW from the mid-Sahara region towards the southern shore of Tethys. Dinosaur-bearing units in the ‘continental intercalaire’ have been dated to the Hauterivian to Cenomanian, and the Chenini Formation is possibly Albian in age. Dinosaur fossils include abundant teeth of the theropods Carcharodontosaurus and Spinosaurus, as well as postcranial elements of theropods and a medium-sized sauropod. A tooth of an ornithocheirid is the first report of a pterosaur from the region. The dinosaur bones and teeth were transported some distance and deposited in a channel lag, associated with less damaged locally derived material such as fern fronds, coprolites, fish teeth and scales, and crocodilian scutes.

A new dermochelyid sea turtle, Arabemys crassiscutata n. gen, n. sp., is described on the basis of epithecal shell mosaic ossicles from the Late Paleocene—Early Eocene of Saudi Arabia. This is the oldest and the most primitive known representative of the dermochelyids having an epithecal shell mosaic.

A new assemblage of marine vertebrates from northern Saudi Arabia, east of the Nafud, leads us to reconsider the age of the top unit of the Aruma Formation, the Lina Member, hitherto referred to the Maastrichtian. This assemblage contains the remains of a dozen selachian and actinopterygian fishes, as well as those of a giant sea turtle representing a new dermochelyid taxon. It suggests a Late Paleocene to Early Eocene age for this unit. This new dating and a revision of the stratigraphic position of the Lina Member demonstrate the existence, on a regional scale, of an important hiatus at the K-T boundary.

The most abundant and most diverse dinosaur remains hitherto found in Thailand come from the Sao Khua Formation, now considered pre-Aptian, Early Cretaceous in age. This assemblage includes theropods (the early and primitive tyrannosaurid Siamotyrannus isanensis ; an early but relatively advanced ornithomimosaur; the enigmatic Siamosaurus suteethorni , and possibly another, very small theropod) and sauropods ( Phuwiangosaurus sirindhornae and another, poorly known taxon). The Sao Khua fauna, which includes neither Psittacosaurus nor iguanodontids, seems to be older than any of the vertebrate assemblages from the Gobi Basin. Several of the dinosaurs from the Sao Khua Formation may be close to the origin of groups that later played an important part in the dinosaur faunas of Asia (`nemegtosaurid' sauropods) or both Asia and North America (tyrannosaurids, ornithomimids).

New pterosaur remains consisting of jaw fragments of toothless taxa and isolated teeth are described from the red beds of the Kern Kern region of southern Morocco. The stratigraphic position of those red beds is discussed and it is concluded that they are in all likelihood early Cenomanian in age. At least four taxa of pterodactyloid pterosaurs are present. The toothless jaw fragments are referred to the families ?Pteranodontidae, ?Azhdarchidae and Tapejaridae. Four different morphotypes can be distinguished among the isolated teeth. They are tentatively referred to the Ornithocheiridae. This assemblage reveals a high diversity of pterosaurs in Africa during the early Upper Cretaceous. The possible occurrence of tapejarids and anhanguerids indicates relationships with the somewhat older pterosaur assemblage from the Santana Formation (Aptian/Albian) of Brazil. If confirmed, the presence of azhdarchids and pteranodontids in the early Cenomanian suggests an early differentiation of these essentially late Late Cretaceous groups of large pterosaurs.

A new locality of Late Cretaceous (probably Early Maastrichtian) age near Cruzy (Herault, southern France) has yielded a varied vertebrate assemblage consisting of lepisosteid fish, albanerpetontid and anuran amphibians, pleurodiran and cryptodiran turtles, squamates (including varanoids), mesosuchian and eusuchian crocodilians, dinosaurs (abelisaurids, dromaeosaurids, titanosaurids and Rhabdodon) and enantiornithine birds. This fauna provides new evidence about the composition of Late Cretaceous European ecosystems.

A pterosaur specimen, consisting of the associated anterior portions of upper and lower jaws, is reported from the upper Kimmeridgian Argiles d'Octeville, in the cliffs of the Cap de la Hève, near Le Havre (France). It is described as a new taxon, Normannognathus wellnhoferi, and referred to the Germanodactylidae. Normannognathus wellnhoferi is distinguished by the association of jaws which bear teeth up to their anterior tip and a tall sagittal crest, formed by the premaxillae, which begins anterior to the nasopreorbital fenestra, has a concave anterior edge, and is much higher than the maxilla at that level. The Dsungaripterus-like crest and the slightly upturned upper jaw support the idea of a close relationship between the Germanodactylidae and Dsungaripteridae.

New discoveries afford a much better knowledge of the large birds previously reported from the Upper Cretaceous of southern France on the basis of a single synsacrum fragment. An incomplete pelvis consisting of the synsacrum with part of the ilia is used to define a new taxon of bird, Gargantuavis philoinos , to which a femur is also referred. This bird is characterized by its very large size (comparable to that of an ostrich), a broad pelvis with an anteriorly placed acetabulum, and a short robust femur. The occurrence of this very large, flightless, bird in the Late Cretaceous shows that, contrary to widespread opinion, the evolution of large terrestrial birds was not simply the result of adaptation during the Cenozoic to ecological niches left empty by the extinction of the dinosaurs. It also strongly suggests that some of the large fossil eggs from the Upper Cretaceous of southern France were laid by large ground birds rather than dinosaurs.

A very large pterosaur cervical vertebra is described from the Upper Maastrichtian deposits of Mérigon, in the foothills of the French Pyrenees. It resembles the vertebrae of Quetzalcoatlus, from the Maastrichtian of Texas, more than those of Arambourgiania, from the Maastrichtian of Jordan. The estimated wing span of the Mérigon pterosaur is close to 9 m, which makes it one of the largest known flying creatures. Giant pterosaurs still had a wide geographical distribution at the end of Maastrichtian time, which is not suggestive of a declining group, although it is difficult to obtain an accurate estimate of taxonomic diversity of terminal Cretaceous pterosaurs on the basis of available data.

A tibia with a fused fibula from the Lower Cretaceous of Changji (Xinjiang, China), originally interpreted as possibly belonging to an ornithurine bird, is redescribed and interpreted as belonging to a dsungaripterid pterosaur.

We have carried out a paleomagnetic study (12 sites, 85 samples) of Early-Middle Jurassic limestones and sandstones from the Mae Sot area of western Thailand. This area is part of the Shan-Thai-Malay (STM) block, and its geological characteristics have led some authors to suggest a Late Jurassic accretion of this region against the rest of Indochina along the Changning-Menglian zone, the latter sometimes being interpreted as a Mesozoic suture. The high-temperature (or high-coercivity) component isolated yields a paleodirection at D = 359.8 °, I = 31.4 ° (α95 = 5.0 °). The primary nature of the magnetization acquisition is ascertained at a site with reversed polarity and a positive fold test (at the 95% confidence level). Comparison of the Mae Sot paleolatitude and another one from the STM with those recently published for the Simao and Khorat blocks show no significant difference at the 95% level, showing that the STM was situated close to, or had already accreted with, the Simao or Khorat blocks in the Early-Middle Jurassic. Comparison of the latitudes from these blocks with those from China indicates a relative southward motion of 8 ± 4° of Indochina as a single entity relative to China. Most rotations of these regions relative to China are found to be clockwise (between 14 and 75°). These rotations, and most prominently the 1200 ± 500 km post-Cretaceous left-lateral motion inferred for the Red River Fault, provide quantitative estimates of the large amount of extrusion of Indochina with respect to the rest of Asia.

In 1923, H. C. T’an and O. Zdansky collected remains of an ankylosaurid dinosaur in the Late Cretaceous Wangshi Group of the Laiyang region, in eastern Shandong (China). Apart from a few caudal vertebrae, this material, which is kept at the Palaeontological Institution of the University of Uppsala (Sweden), was never described or figured. It includes a well-preserved sacrum with the attached right ilium and part of the presacral rod, caudal vertebrae, a left femur and a dermal scute. This material is referred to an ankylosaurid of the genus Pinacosaurus Gilmore, 1933, on the basis of the widely divergent ilium bearing a strong ventral ridge and of the slenderness of the femur. In the absence of cranial material, a specific attribution is difficult and the Uppsala material is referred to as Pinacosaurus cf. grangeri (P. grangeri being the only generally accepted species of Pinacosaurus). This is the first record of Pinacosaurus outside the Gobi Basin of Mongolia and northwestern China. In the Gobi Basin, Pinacosaurus has been reported only from the Djadokhta Formation or its equivalents, of supposed Campanian age, and it is suggested that at least the part of the Wangshi Group which yielded the Shandong Pinacosaurus may be of roughly the same age as the Djadokhta Formation.

The distal part of the fused ischia of a prosauropod from the Nam Phong Formation (late Triassic) of Phetchabun Province, in northeastern Thailand, is described. Comparisons with various prosauropods, as well as with an early sauropod, show that the Thai specimen is especially robust. However, the available material is too incomplete to warrant a precise identification. It is the first vertebrate fossil found in the Nam Phong Formation, the oldest known dinosaur from southeast Asia, and the first prosauropod to be reported from that region.

Pterosaurs were a peculiar group of Mesozoic vertebrates, which acquired the ability to fly in an original way, using a membrane attached to a single finger of the hand. Ever since the first description of a pterosaur skeleton in 1784, these remarkable animals have elicited much discussion and controversy among palaeontologists, and many basic questions about their origin, evolution and biology remain disputed. In the last few years, interest in pterosaurs has been revived by numerous discoveries of new and sometimes remarkably preserved specimens, which have enlarged and changed our picture of this group. The volume begins with descriptions of several new pterosaurs from the Triassic, Jurassic and Cretaceous of Europe, North and South America, and Africa. Following this, alternative hypotheses of pterosaur phytogeny and evolution are put forward. Several papers discuss the functional anatomy of pterosaurs and its implications for aerial locomotion. The study of pterosaur footprints provides important new evidence concerning their terrestrial locomotion, and this approach is used in several contributions. A developing aspect of pterosaur research is bone histology, as shown by the final papers in this collection.

BackgroundThe genus Gavialis comprises a single living but endangered species, G. gangeticus, as well as fossil species recorded in the Miocene to Pleistocene deposits of the Indian subcontinent. The genus is also represented in the Pleistocene deposits of Java by the species G. bengawanicus, which was recently recognized to be valid. Surprisingly, no detailed report of the genus exists between these two provinces and the recent evolutionary history of Gavialis is not understood.Methodology/principal findingsWe report new material consisting of skull and mandibular remains of Gavialis from the Early Pleistocene of Khok Sung, Nakhon Ratchasima Province, northeastern Thailand. The Gavialis material described herein is attributed to Gavialis cf. bengawanicus and sheds new light on the occurrence of the genus in mainland SE Asia.Conclusions/significanceComparison of this new material with other species referred to the genus Gavialis led us to preliminary restrict the content of the genus to three species, namely G. gangeticus Gmelin, G. bengawanicus Dubois and G. lewisi Lull. The occurrence of G. cf. bengawanicus in Thailand allows us to propose a scenario for the dispersal of Gavialis from Indo-Pakistan to Indonesia, thus bridging a geographical gap between these two provinces. Dispersal by sea appears a less likely possibility than dispersal through fluvial drainages.

Si pendant longtemps les hommes ont ignore, voire nie, le phenomene d’extinction des especes, celui-ci est aujourd’hui au cœur du debat ecologique et suscite de nombreuses idees recues : « La selection naturelle conduit a l’extinction des especes », « Les dinosaures se sont eteints brutalement », « Le changement climatique est un facteur majeur de l’extinction des especes », « Le dodo a ete extermine par l’homme », « Il est possible de faire revivre des especes disparues », « L’espece humaine pourrait, elle aussi, disparaitre »… A l’aube de ce que certains presentent comme la 6e extinction de masse, Eric Buffetaut nous eclaire sur le cycle complexe de l’evolution des especes, au travers d’une approche historique et scientifique, illustree par de nombreux exemples. Specialiste de la paleontologie des vertebres et docteur es sciences, Eric Buffetaut est directeur de recherche emerite au CNRS (Laboratoire de geologie de l’ecole normale superieure, Paris).

A large heterocoelous cervical vertebra from the Late Cretaceous of Cruzy (Hérault, southern France) is described and referred to the giant bird Gargantuavis philoinos Buffetaut & Le Loeuff, 1998, confirming its avian nature. Gargantuavis appears to have been a long-necked bird with possibly a relatively small skull. Derived features such as heterocoely suggest that Gargantuavis was an advanced ornithuromorph, close to ornithurines.

An isolated posterior cervical vertebra of a sauropod discovered at Phu Dan Ma (Kalasin Province, northeastern Thailand) is the first informative postcranial specimen from the Phu Kradung Formation, a Upper Jurassic to Lower Cretaceous continental unit. The vertebra is referred to the family Mamenchisauridae, otherwise mainly known from China. In addition, spatulate teeth from the same formation and a mid-dorsal vertebra from the Upper Jurassic Khlong Min Formation of southern Thailand are reassigned to this family. The occurrence of mamenchisaurids in the earliest Cretaceous of Thailand supports a hypothesis of geographical isolation of Central, Eastern, and Southeast Asia during the Late Jurassic. It also suggests that the main changes in their dinosaur assemblages occurred during the Early Cretaceous, rather than at the Jurassic-Cretaceous boundary.

BackgroundLong bone histology of the most derived Sauropoda, the Titanosauria suggests that titanosaurian long bone histology differs from the uniform bone histology of basal Sauropoda. Here we describe the long bone histology of the titanosaur Ampelosaurus atacis and compare it to that of basal neosauropods and other titanosaurs to clarify if a special titanosaur bone histology exists.Methodology/principal findingsAmpelosaurus retains the laminar vascular organization of basal Sauropoda, but throughout most of cortical growth, the scaffolding of the fibrolamellar bone, which usually is laid down as matrix of woven bone, is laid down as parallel-fibered or lamellar bone matrix instead. The remodeling process by secondary osteons is very extensive and overruns the periosteal bone deposition before skeletal maturity is reached. Thus, no EFS is identifiable. Compared to the atypical bone histology of Ampelosaurus, the large titanosaur Alamosaurus shows typical laminar fibrolamellar bone. The titanosaurs Phuwiangosaurus, Lirainosaurus, and Magyarosaurus, although differing in certain features, all show this same low amount or absence of woven bone from the scaffolding of the fibrolamellar bone, indicating a clear reduction in growth rate resulting in a higher bone tissue organization. To describe the peculiar primary cortical bone tissue of Phuwiangosaurus, Ampelosaurus, Lirainosaurus, and Magyarosaurus, we here introduce a new term, "modified laminar bone" (MLB).Conclusions/significanceImportantly, MLB is as yet not known from extant animals. At least in Lirainosaurus and Magyarosaurus the reduction of growth rate indicated by MLB is coupled with a drastic body size reduction and maybe also a reduction in metabolic rate, interpreted as a result of dwarfing on the European islands during the Late Cretaceous. Phuwiangosaurus and Ampelosaurus both show a similar reduction in growth rate but not in body size, possibly indicating also a reduced metabolic rate. The large titanosaur Alamosaurus, on the other hand, retained the plesiomorphic bone histology of basal neosauropods.

We report the discovery of a dinosaur assemblage in the non-marine Late Maastrichtian of the Corbieres region of southern France; this allows the reconstruction of the succession of dinosaur faunas during the Maastrichtian in western Europe. An Early Maastrichtian fauna dominated by titanosaurid sauropods was replaced by a Late Maastrichtian assemblage dominated by hadrosaurs. This important faunal replacement seems to coincide with environmental changes (documented by sedimentological and palynological evidence) which have been linked to a marine regression during the Maastrichtian. This suggests that sea-level changes influenced the evolution of dinosaur faunas in Europe during the Late Cretaceous, but were not sufficient to cause the final extinction of dinosaurs, for which other causes must be sought.

Resume L'actualisation de l'inventaire de la faune ichthyologique de Cerin permet de degager le degre de certitude concernantl'identification de chaque taxon et l'etablissement de ses affinites phylogenetiques. Le nouveau regroupement des taxons et l'abondance des formes juveniles (Notagogus, Leptolepides, et cf. Ascalabos) exhumees au cours des nouvelles fouilles modifient nos connaissances sur l'abondance relative des diverses especes. Il existe peu d'elements propres a Cerin et les formes communes a Cerin et aux gisements bavarois sont plus frequentes que ce qui etait admis jusqu'ici, les differences portant plus sur les conditions de milieu que sur les differences d'âge des gisements.

Resume Quinze ans de fouilles ont complete et diversifie l'image de la faune d'echinodermes des calcaires de Cerin. Un bilan des divers groupes est presente dans cet article. En attendant une etude systematique detaillee qui sera realisee a la fin des fouilles, ce travail aborde essentiellement les problemes de la taphonomie des echinides. Les tests sont rares, mais toujours entiers, avec ou sans radioles. Ces derniers sont frequents a l'etat isole. Les modeles experimentaux presentes par Kidwell & Baumiller (1990) et Greenstein (1991) montrent que la desarticulation des theques est un processus rapide, surtout sous les conditions climatiques et bathymetriques envisagees a Cerin (climat intertropical, faible profondeur). Les oursins (les echinodermes en general) devraient etre rares a Cerin en raison de bien des facteurs paleobiologiques et paleogeographiques; or, ils sont presents et la majorite d'entre eux ne presente pas de dislocation des theques. Cela tient au fait qu'il s'agit d'organismes arrives dans la lagune au cours d'evenements hydrodynamiques episodiques et brefs, suffisamment violents pour les transporter. Ils y sont arrives vivants ou morts depuis tres peu de temps compte tenu de leur etat de conservation (piquants en connexion avec la theque, tests denudes et vides, mais non brises). le recouvrement sous des voiles microbiens et/ou l'enfouissement sous un lit de boue carbonatee s'est fait rapidement, avant que ne soit atteint le seuil de desagregation instantanee (une dizaine de jours en milieu intertropical). Les radioles isoles ont ete orientes par les derniers courants ayant balaye le fond de la lagune.

The Cerin Lithographic Limestones do not cover a wide area. They correspond to numerous lagoon in-fillings of limited development, within a wide emerged area characterized by sandy (skeletal) limestones mainly of coral origin (Landaize Limestones). At the village of Cerin where an excavation for paleoecological studies is located, the sandy Landaize Limestones provide the lithographic limestone substrate. Their cementation is partly of supratidal and/or intertidal origin, but frequently shows phreatic freshwater features. Finally, microbial cements (bacteria or cyanobacteria) reflect a major process of lithification. The original substrate consisted of grainstones, the top of which was considerably eroded, producing uneven relief with steep slopes and even cliffs, sometimes reaching several metres in height. The erosion processes were probably mechanical in origin, but also biochemical (biokarst) and especially biological (bioerosion by grazing, boring and microbial erosion). Lime mud which produced the lithographic limestones filled the hollows between the substrate reliefs. Around areas where the uneven rocky substrate had steep gradients locally developed gravity flows occur. These are capped with microbial films which are affected by superficial slides showing more or less concentric or complex wavy structures. Locally, true slumps giving rolls and synsedimentary microfolds also occur.

Resume Les anciennes collections comportent moins de 10 ammonites auxquelles s'ajoutent environ 60 pieces recueillies insitu. Ce materiel nouveau confirme l'extreme rarete des ammonites dans les calcaires lithographiques superieurs ou cinq niveaux seulement ont livre chacun un exemplaire. Tous les autres proviennent des calcaires lamines inferieurs. Est egalement confirmee la mauvaise conservation d'ensemble des restes toujours deposes a plat a la surface des bancs ou des lamines a l'etat de compression. L'absence d'empreintes de la region ventrale (la ou elle a touche le fond) et des aptychus a l'interieur ou a proximite de l'ammonite plaide en faveur de coquilles arrivees vides dans la lagune de Cerin. Un Aspidoceras et deux perisphinctides seulement sont determines jusqu'a l'espece, ces derniers proches de formes connues du Tithonien inferieur de Solnhofen ce qui tend a rajeunir a nouveau legerement les depots de Cerin.

Resume Les asterides des Calcaires lithographiques kimmeridgiens de Cerin (Ain) sont rares, mais bein conserves. Trois especes, dont une nouvelle, appartiennent aux familles des Goniasteridae et des Astropectinidae. Elles ne sont connues que de ce seul gisement. L'examen des conditions taphonomiques conduit a penser que les specimens preserves ne sont pas autochtones.

Comparison of the tetrapod assemblages from Late Jurassic (Franconia, Cerin, Canjuers) and Early Cretaceous (Montsec, Las Hoyas) lithographic limestone localities in Germany, France and Spain, reveals both important ressemblances and striking differences. The latter are explainable by different collecting histories, taphonomic biases, different depositional environments, and differences in geological age. The tetrapod assemblages from the lithographic limestones of Europe are unbalanced and the reasons for this are worthy of further investigation.

Bed-by-bed analyses of a lateral set of profiles in the Eichstatt area, and of one profile of Cerin reveal some analogies and some differences. The analogies are: A.1) There appear three distinct lithofacies which differ in their contents of insolubles in 1 : 3 : 10 ratios. A.2) The 12 analyzed elements can be separated into 3 groups: a “clastic group” (Si, Al, K, Fe) with very similar trends in profile, caused by the detrital input of silicate minerals; a “semiclastic group” (Ti, Rb, Ba, P), which follows the clastic trend, but not quantitatively; and Mn, S, Sr (and Mg) which form the “diagenetic group” with special behaviour. The differences are: B.1) Cerin in general is purer than Eichstatt, but according to the correlation lines in 2-element-diagrams it has relatively less K and Al, more Si and Fe, and more Mg in the carbonate phase. B.2) For Eichstatt it can be suggested that the sediment was brought into the plattenkalk basin as a ready mixture of carbonate and non-carbonates. At Cerin the relation between thickness and contents of insolubles proves the “Seibold-rule”: dilution of insoluble input by in situ carbonate production. Cerin is a simple rhythmite, whereas Eichstatt is dominated by “undulations”. These features, and the differences described in B.2, are used as the basis for definition of “Plattenkalk C-type” and “E-type”.