The biometric and morphologie variability of the cheek teeth in the end-of-the-phylum species Lophiodon lautricense Noulet studied in this note, reposes on the observation of about 800 teeth. These were revealed to be little variable in absolute dimensions. The considerable morphologie variability in the upper premolars permitted the problem of the molarization process to be taken up. An hypothesis concerning the order of eruption of the cheek teeth is formulated based on an examination of a large number of milk dentitions. In conclusion, it is suggested that reservations be held on the value of dental characters classically used in systematics for the group under consideration. 

The Pantolestidae from the middle eocene of Bouxwiller are the subject of a detailed study. Buxolestes hammeli (n. g., n. sp.) is not closely related to any other European or North American form described until now; it presents, however, some characters in common with Pantolestes, a form of the same age from North America. A parallel evolution from a common ancestral form could explain this ressemblance.
Another form (gen. and sp. indet.) accompanies Buxolertes hammeli in the Bouxwiller fauna.
  

The description of new material from three classic middle Eocene localities of western Europe permits the addition of details to the systematics of primitive Pseudosciurids. The cranial anatomy of Protadelomys cartieri (STEHLIN and SCHAUB) from Egerkingen is described here and compared to that of the Adelomyines from the late Eocene, until now the only ones known. The morphologic and biometric study of the dentition of P. cartieri compared to that of P. alsaticus n. sp. from Bouxwiller and P. Iugdunensis n. sp. from Lissieu, forms respectively older and younger than P. cartieri, permits the evolutionary tendencies of the group to be demonstrated and shows that notable differences in age exist between these localities. This ensemble of forms can constitute a valuable guide lineage in the establishment of a fine stratigraphy of the period. Other less well known lineages are present at Egerkingen along with P. cartieri. They can be related to genera that have been noted int he late Eocene. In conclusion, a criticism of recent zonation proposals, made by divers authors, completes this article. 

The murid fauna of the terminal Pliocene of southwest Europe is rich in at least eight genera and ten species. With the species belonging to the genera Apodemus, Rhagapodemus, and Stephanomys not being studied here, the study of the other murids resulted for one thing in the description of three new genera and three new species: Castillomys crusafonti n. g., n. sp., Occitanomys brailloni n. g., n. sp., Anthracomys meini n. sp., Valerymys ellenbergerí (THALER) n. g., and for another thing in the recognition of a form hitherto unknown in this region, Micromys praeminutus KRETZOI. Systematic study has shown that certain species of the terminal Pliocene fauna had their ancestors in the Turolian fauna presently known in Spain. The evolutionary lineages thereby recognized have been studied more in detail and a list of the evolutionary tendencies of the dendal characters has been given. A chart of the probable phyletic relationships between the different murids of the Pliocene faunas of southwest Europe (With the genus Rhagapodemus and Apodemus dominans being excluded) is given in conclusion of this work. 

The Oligocene deposits of the Ulantatal area in Inner Mongolia (China) contain among the richest mammalian faunas from Asia. To date, only some parts of the rodent faunas have been described. Here, we propose to review the rodent faunal lists for each site, including the description of a few new rodent specimens. We describe three additional rodent species: the Cylindrodontidae Anomoemys lohiculus, the Eomyidae Asianeomys sp., and the Dipodidae Litodonomys huangheensis. This study allows us to constrain the stratigraphic range of Anomoemys lohiculus, which ranged from the late Early Oligocene to the early Late Oligocene in this area. Asianeomys sp. and Litodonomys huangheensis are dated from the latest Oligocene. These Oligocene deposits consist now of more than 70 species of mammals if we include the fauna from Kekeamu. This latter corresponds to the basal part of the Ulantatal Formation and could be dated biochronologically from the earliest Oligocene. When compared to the faunas from the Valley of Lakes in Central Mongolia, the Ulantatal faunas present a great majority of rodents, and this difference can be partly explained by sampling and description biases regarding macro-mammals. This study also shows that variations existed between Inner and Central Mongolia, especially regarding the composition of the rodent paleocommunities. However, the assessment of their evolutionary history in this part of Asia with respect to the important climate and environment changes, require further precisions and more material than current data allow. 

Based on fossil discoveries and phylogenetic studies, an Eocene Asian origin for hystricognathous rodents and anthropoid primates has gained strong support in recent years. The two groups then invaded both Africa and South America, which promoted their evolutionary success. However, the fossil record has so far failed to constrain the nature and precise timing of these pivotal dispersal events. In Africa, given the apparent absence of hystricognaths and anthropoids in early to early middle Eocene localities, it is suggested that these mammal groups dispersed from Asia to Africa sometime during the middle Eocene. In this paper, we report the discovery of several isolated teeth of a rodent from a new vertebrate locality situated in central Tunisia (Djebel el Kébar, KEB-1), dating from the late middle Eocene (Bartonian, ~39.5 Myr). These fossils document a diminutive new species of Protophiomys (P. tunisiensis nov. sp.), a basal genus of hystricognathous rodents which is well known from several North African mammalian-bearing localities of the end of the Eocene. The teeth of P. tunisiensis display a suite of anatomical details comparable with those observed in the other species of the genus, but with a lesser degree of development. Such an apparent primitive evolutionary stage is corroborated by the greater antiquity of this Tunisian species. P. tunisiensis nov. sp. is so far the most ancient representative of hystricognaths in Africa. However, it can be expected that hystricognaths were already present on that landmass given the new data on early caviomorphs recently reported from South America (at ~41 Myr). The arrival of hystricognaths in Africa from South Asia certainly predates the depositional period of the Kébar sediments, but perhaps not by much time. 

Based on isolated teeth two new scyliorhinid shark species, Scyliorhinus biformis nov. sp. and Scyliorhinus suelstorfensis nov. sp., are described from the Sülstorf Beds, early-middle Chattian, of Mecklenburg, northeastern Germany. They form part of a speciose assemblage of necto-benthic sharks and batoids which populated the warm-temperate to subtropical upper shelf sea of the south-eastern North Sea Basin. 

The genus Plagiolophus is documented, almost solely in Western Europe, from the middle Eocene up to the mid Oligocene (MP 12 to MP 25), i.e. more than for 15 MY. Seventeen species are now recorded whose two of them are new, P. ringeadei nov. sp. and P. mamertensis nov. sp. Some anatomical variations and the deflection of certain evolutionary trends justify the distinction of three subgenera, Paloplotherium, Fraasiolophus nov. and Plagiolophus s.s. The genus displays a wide range in size and weight (between 10 and 150 kg). The detailed description of the skull of several species is here given for the first time.
Despite important evolutionary drifts during this long time span, the dentition shows a great structural homogeneity, which renders difficult the determination of fragmentary specimens or isolated teeth. It is characterized by a great heterodonty; premolars are little molarized and present a certain regression through time with paradoxically some progress in the molarization. The hypsodonty increases: the first Plagiolophus are hardly less brachyodont than Propalaeotherium, and the last ones are nearly as hypsodont as Merychippus from the early Miocene. The upper molars change from a wide crown pattern, with an open occlusal surface, lightly oblique transverse lophs and rounded internal cusps, to a narrower pattern, with a frontally constricted occlusal surface and internal lophs aligned parallel to the ectoloph. The M3/3 become always longer.

The dental enamel displays horizontal Schreger-bands with imprecise limits occupying only the middle part of the enamel layer. The dentine is remarkable by its high rate of pericanalicular dentine. The crown cementum, lacking in earlier forms, increases to the point where it fills the occlusal valleys of the
teeth.

The masticatory musculature shows a increasing prominence of the temporal, with probably an important role devoted to the pterygoid muscles in lateral movements related to a two-phase type of chewing.

The evolution of the dentition, of the masticatory musculature and of the repartition of masticatory forces indicate that the Plagiolophus have known different diets through their long evolutionary history; at first browsers they became mixed feeders and finally grazers. Their relatively long neck allowed these animals to reach different vegetal layers. The strength of the nuchal crests also suggests that they were able to have strong backwards movements of the head to pull up their food.

This evolution of diet seems related to the slow degradation of environmental conditions attested during this period in western Europe, with the generalization of more open landscapes, increasing aridity and more marked seasons.

Besides, a remodeling of the face is ontogenetically and along time observed, in relation with the evolution of the masticatory apparatus and especially with that of the mandibular lever arm. The postcanine diastemata become longer in the course of evolution; the free extremities of the nasals are always relatively long which contradicts the hypothesis according to which Paloplotherium may have had a trunk. At last the lineage Fraasiolophus can be distinguished by the presence of a deep malar fossa, probably related to a strong development of the maxillo-labialis superior muscle.

The orbit is always large and tends to increase in size, which indicates a good development of the vision and its increasing role in the life relations. A peculiar type of epitympanic sinus could have been used as a resonance chamber insuring a certain amplification of sounds before their transmission to the eardrum. The endocranial cast reveals a relatively large brain with an advanced degree of gyrencephaly. Beside the role eventually played in food research and social relations, these neurophysiological abilities, also related to an advance in cursorial fitness, could have contributed to the survival of these animals facing the predation pressure of the first fissipede carnivores and the competition with new immigrant herbivores after the "Grande Coupure".
On the basis of some shared apomorphies with the Pachynolophinae, which prevent from considering the latter as Equidae (molarization of the premolars, reduction of the premaxilla dorsal apophysis, peculiar epitympanic sinus, splitting of the jugular process), the hypothesis of an autochthonous origin of Plagiolophus issued from a form near Propalaeotherium, is once again proposed and discussed. Finally, intra-generic relationships are taken into consideration. 

Description of four new rodents from a recently discovered locality at Montalban. Theridomys crusafonti nov. sp. is considered as the ancestry of T. Iembronicus. Theridomys varian: nov. sp. includes «Theridomys» morphotypes and «Blainvilllimys» morphotypes; it could be ancestral to B. blainvillei. Pseudoltinomys nanus nov. sp. represents a new lineage paralleling in evolution that of P. gaillardi (which is equally found at Montalban). Pseudocricetodon montalbanensis nov. gen., nov. sp. designates a lineage of very small Cricetidae accompanying Eucricetodon. With these well defined new species and six others present in the locality, Montalban appears as the best faunal reference point within the biochronologic zone of La Sauvetat.
As an annex, discussion of two rodent specimens from the classic localíty of Tárrega, close in age to that of Montalban. 

The exploitation of new early Eocene localities in the Paris Basin has resulted in the collecting of  numerous mammalian remains, among which are about 300 isolated teeth representing the rodents. They belong, for the most part, to the paramyid group. Only the latest level of the early Eocene has yielded rodents belonging to the pseudosciurid group. The paramyids, the object of this study, are represented by at least 5 genera and 10 species; they are distributed among 4 clearly dilferentiated subfamilies : Paramyinae Simpson 1945, Pseudoparamyinae Michaux 1964, Ailuraviínae n. subf., Microparamyinae Wood1962.
It results from this study that the principal types of rodents in the middle and late Eocene of Europe are clearly related to the forms described here: Plesiarctomys Bravard 1850 is related to Pseudoparamys Michaux 1964, Ailuravus Rütimeyer1891 to Meldimys n. gen., Gliravus hammeli Thaler 1966 to Microparamys nanus (Theilard1927), and some Masillamys Tobien 1954 to Microparamys russelli Michaux 1964 and to M. sp. 1. Gliravus and Masillamys are the oldest representatives of the Gliridae and the Pseudosciurídae, respectively, families which will progressively replace the Paramyidae in the course of the middle and late Eocene.
Two stages can be recognized in the history of te European Paramyidae fauna during the course of the early Eocene: the older is characterized by the Mutigny fauna, the younger by the Cuis fauna.
The Mutigny fauna appears already rather diversified and does not completely correspond, point by point, to the homologous fauna of North America. A geographic differentiation seems to have been manifested rapidly, unless the fauna established in Europe was already a little different from that which established itself in North America. 

In recent years, the techniques of chemical preparing have permitted a rich paleontologic material to be obtained from the phosporitic sediment of Bouzigues (Hérault, France). The fauna of this locality is comprised of quite varied microvertebrates, amphibians, reptiles, birds, mammals. Twenty five species of the latter, belonging to seven orders, are today known from the site. Among them, the numerous rodents have allowed L. Thaler to chronologically situate this fauna in the Zone of Laugnac (<< late Aquitanian ›> of some authors).
The chiropterans are, with the rodents, the best represented of the locality's mammals. Three families comprise the bat fauna, with nearly complete dominance by one of them (Hippoxideridae) over the two others (Megadermatidae and Vespertílionidae)
Six forms are described, of which three are new species and one a new sub-genus.
Megaderma braillomi n. sp., an animal of rather large size, shows like the Miocene megaderms several evolved dental characters, translating the adaptation of these animals to a partially carnivorous regime. The Bouzigues species seems, however, to represent a particular lineage.
Hipposideros (Brachipposideros n. subgen.) dechaseauxi n. sp. and Hípposideros (Brachipposideros) cf. collongenris Depéret, small sized forms, belong to a group rather well represented in the late Oligocene and early Miocene of Europe, and not distinguished until now within the genus Hipposideros.
Hipposideros (Pseudorhinolophus) bouziguensis n. sp., is the most abundant mammal in the locality and, occuring at the Oligocene-Miocene limit, the last representative known of the subgenus Pseudorhínolophus, common in Europe from the middle Eocene.
However, beyond Neogene and Quaternary times, certain among the numerous living species of Hipposideros are close to Pseudorhinolophus and others to Brachipposíderos. 'This fact would in the future justify a global revision of the genus, on the basis of comparative anatomy of the squeleton and of the teeth.
The bat fauna of Bouzigues is completed by two small Vespertilionidae, rare forms, Myoris sp. I and sp. II.
  

The locality of Fons 1, one of the fossiliferous outcrops in the late Eocene limestones of Fons-outre-Gardon (Gard), has yielded varied remains of mammals. The specimens were prepared by dilute acetic acid attack on the rock and by impregnation with an acrylic resin.
This fauna, rich with about 20 species, can be included in the biochronologic zone of Euzet. The Palaeotheridae (sensu Simpson 1945), represented by 6 species, occupy a predominant place; Plagiolophus annectens is particularly abundant, comprising 55% of all the specimens found.
The abundance of this species has permitted a detailed comparative study with the corresponding form from Euzet. The quantitative tests brought out a slight but highly sígnificant difference between the average dimensions of the teeth in the two populations. Moreover and in spite of the feeble rate of evolution in the Plagialophus dentition, diverse archaic particularities can be seen which permit the conclusion that the form from Fons 1 is a little the older. This conclusion is corroborated by observations on the other palaeotherids, particularly Lophiotherium aff. cervulum, whose dental evolutionary stage is intermediate between those of the corresponding forms known from Robiac and Euzet.
A new species of Pachynolophus is described, P. garimondi n.sp., the last representative known of the genus. lts teeth are distinguished by their size, a great heterodonty, and the weakness
of their cingula. 

This paper proposes a systematic revision of the Oligocene Mongolian Ctenodactylidae, on the basis of abundant material obtained by screen/washing operations in stratified localities of the Ulantatal area (Inner Mongolia) (UTL1, 2, 3, 4, 5, 7, 6 & 8). A Chinese-German team has collected several thousands of isolated rodent teeth, and a number of fragmentary jaws. A new genus is identified (Alashania nov. gen. tengkoliensis nov. sp.), and eight former species are reevaluated, Karakoromys decessus, Tataromys sigmodon, T. minor, T. plicidens, Yindirtemys ulantatalensis, Y. bohlini, Y. deflexus, with several synonymies. A new Yindirtemys species is described: Y. shevyrevae nov. sp. and another one close to that: Y. aff. shevyrevae nov. sp. Four new species, which are rare in the localities, remain in open nomenclature because they are not well-represented. Yindirtemys differs from the other genera by the permanence of crescentic structures, while the other genera show a general reduction of the trigonoid area (= anterior valley). We define a range of size variation for each well documented population. Although the dental morphology shows a wide range of variation, given that transitional morphologies occur in a single locality, it is possible to provide a clear definition for most species. We show that dental patterns of the different genera can be derived from the pattern of Karakoromys. As a number of Tataromyinae have been determined in several localities from China, Kazakhstan and Mongolia, usually on the basis of scarce material, or surface collections, the present study would be used to re-evaluate their attribution inasmuch as the taxa are now placed in the Oligocene stratigraphy. The diversity of sizes and forms reflects the adaptive radiation of the family during the Oligocene, within a forested environment where the vegetation was probably abundant. 

This paper is mainly devoted to the systematics of rodents from two middle Eocene (Bartonian) localities: Chéry-Chartreuve and Rocourt-Saint-Martin (Aisne, Eastern Paris Basin). These two localities are stratigraphically located slightly above the Auversian sands. The two faunas, which comprise 11 and 8 taxa, respectively, are very different in their composition. That of Rocourt-Saint-Martin shows strong similarities with that of the geographically very close locality of Grisolles, referred to the MP16 mammalian Reference level. The very distinct fauna of Chéry-Chartreuve includes a new species of Ailuravinae, Ailuravus nov.sp, and some teeth of the theridomyid Protadelomys, which represent archaic elements in the fauna. The most abundant species of the locality represents a new genus of primitive Theridomyidae. The presence of some teeth belonging to a new species of large Remyinae, Remys nov. sp., of Elfomys engesseri HOOKER & WEIDMANN, and a population of small dimensions referred to the genus Estellomys allow a correlation with Les Alleveys (Switzerland), with however some differences that would indicate an older age for Chéry-Chartreuve. Situated at the base of the "Marinesian" from the Bassin de Paris, this fauna is unquestionably different from those referred to the MP16 reference level and could represent an older level for which the macrofauna remains very poorly known. Conversely, the comparison of rodents from La Livinière II with those present in MP16 faunas, especially those of Robiac (Gard), shows a great similarity between both localities. This casts doubts on whether to keep this La Livinière II faunule to define the current MP15 reference level, while the biostratigraphical position of Pontils 26 (Spain), previously referred to this level, is reconsidered. Chery Chartreuse could be a good candidate for a new definition of the MP15 reference level. 

Since the 19th century, thousands of footprints were observed in the geological series of the French Mesozoic. All are located in the Triassic and Jurassic. After a promising beginning, in France, it is only a few papers which will be published in the first half 20th century, unlike the USA and of others countries of Western Europe. One ought to wait about 1950 for a revival and now they are nearly 200 papers which were devoted to the ichnofossils. The literature abundance and the renewed interest of the naturalists for the palichnologic studies decided to us to write a synthesis work. This one begins with a stratigraphic inventory in which, localisation, age and paleontological contents of about 180 fossiliferous sites are specified. After having pointed out the followed methods, the footprints paleontological interpretation is then approached in detail and the results obtained are replaced in stratigraphy to deduce the fauna evolution during the Mesozoic. So, it appears that Ichnologic data, more varied and rich in the Triassic and Liassic than those relating to the bones, very rare for the considered periods, are very informative. The middle Triassic (Anisian-Ladinian), thus reveals Cotylosauria, Lepidosauria, Crurotarsi with Rauisuchia, Ornithosuchidae, Crocodylia and Dinosauromorpha more the "Prodinosauria": Dinosamiforme whose skeletons are known in Argentina but only in Ladinian. The rather fast domination of Dinosaurs during Norian is also as well shown. The almost exclusive presence of their footprints, up to fifty cm long, in the Lower Hettangian indicates their supremacy in the environments. Footprints characterise not very deep life places located between inter-supratidal limits and often out of water. Sedimentologic and Palaeontologic studies showed that they were great coastal spaces during Middle Triassic, flood-plain with sebkhas while Upper Triassic, and a large !!coastal marsh!! in Grands-Causses during Liassic in which, mainly, fine stromatolithic layers were deposited. During the same periad, bay beaches spread in Vendée. During the Middle Jurassic, they are also brackish to lacustrine environments and recifallagoons in- the Upper Jurassic. Numerous measurements of the footprints and trackways directions showed that the animaIs moved there in weil defined directions, for long periods. They seem due to the palaeotopography of the life environments relatively stable. Also, the discovery of vegetal radicular networks and small footprints far away from the continental borderlands has suggested that the animals continuously lived in these palaeoenvironnements, belonging to large ecosystems, where the sedimentation rate was weak. This explains that thebadies could not fossilize there but only their footprints through the cyanobacterian action in main cases. From the vertical distribution of different ichnospecies, defined with adapted statistical methods, explained in this work, a palichnostratigraphy was established for the Middle Triassic. Although the footprints are also abundant in Hettango-Sinemurian of "Grands-Causses" and the Vendée, it was not possible, up to now, to establish any zonation in this series; Probably because the palichnofauna is too little diversified there, currently reduced to a majority of Theropods II-IV tridactyl traces.
  

The knowledge of the Anchilophini has been lately renewed by the discovery of a rather large amount of new material still largely unpublished. This new material offers the opportunity of a systematic revision of this tribe gathering those of European Eocene Equoidea which bear no mesostyle on upper check teeth and display a heavy trend to the molarization of premolars.

A cladistic analysis has made out two genera, Anchilophus (Paranchilophus included as a subgenus), characterized by a marked lophodonty and the transverse narrowness of the cheek teeth, a rather high hypsodonty, the frequent occurrence of "crochets" and "anticrochets" on the superior ones, and a rather weak molarization of the premolars, opposite to Metanchilophus n. gen. whose cheek teeth are more transversally elongated, less high, less lophodont, with cusps better distinct, enamel thicker and premolars more molarized on the whole.

Three species of Anchilophus are recognized, A. desmaresti, type species of the genus, A. (Paranchilophus) remyi and A. (Paranchilophus) jeanteli n. sp.

The genus Metanchilophus is more diversified with the species dumasi, radegondensis, gaudini (whose a new sub-species M. g. fontensis is defined), depereli, castrensis n. sp. and chaubeti n. sp.

The skull anatomy has been moreover described with several taxa; it brings to light (for all that one can generalize) that Anchilophini were light animals with a slender and elongated snout, a thin zygomatic arch, a rather developed encephalon with an advanced gyrencephaly.

The structure of the nasal opening together with the occurrence of epitympanic sinuses and the molarizing process of the premolars corroborate the attribution of this tribe to the family PalaeotheIiidae. 

Morphological and biometrical description of skulls, teeth, and limb bones of extant and fossil Old World herniones (including E. hydruntinus) and of New World 'stilt-Iegged' and other slender species from Blancan to Holocene. An Appendix presents ways in which the approximate size of some missing bones or dimensions may be deduced from available ones.

The discussed and/or illustrated fossils were found in Bolivia (Tarija), Canada (Yukon), China (Choukoutien, Gulongshan, Jiling, Loufangzi), Ecuador (Oil Fields), Ethiopia (Melka Kunturé), France (Lunel-Viel), Germany (Süssenborn), Greece (Agios Georgios, Petralona), Hungary (Dorog), Italy (Romanelli), Mexico (Cedazo, San Josecito), Mongolia (Sjara-osso-gol), Spain (Venta Micena), ex-Soviet Union (Akhalkalaki, Binagady, Chokurcha, Chukochya, Kabazi, Kolyma, Krestovka, Kurtak, Staroselie, Tologoj), USA (Alaska, Arkalon, Cedar Meadow, Channing, Conkling, Dry Mountains, Hay Springs, Leisey Shell Pit A, Lissie Formation, Natural Trap, Pool Branch, Powers Ranch, Rock Creek, San Diego, Santo Domingo, Seymour Formation, Shelter, Slaton, Trinity River). Numerous raw or statistically elaborated data are given in Tables.

There is no evidence for the existence of Old World hemiones in the New World nor of 'stilt-Iegged' equids in the Old World. The first 'stilt-Iegged' equid was found at Santo Domingo, New Mexico, and is believed to be Late Blancan. It was probably at the origin of E. calobatus (Arkalon, Rock Creek) and of the smaller E. semiplicatus (Channing, Rock Creek). Slender, but not 'stilt-Iegged', equids found at Natural Trap, Wyoming, ca. 12 ky ago belong to Amerhippus. AlI these species share with Oid World Sussemiones (and some hemiones) peculiar patterns on the lower cheek teeth.

The slender Equus sp. B of Leisey Pit A, Florida, ca. 1.2 Ma, as weIl as Amerhippus francisci and E. tau (probably a senior synonym of E. quinni) share conventional lower cheek teeth patterns. The skulls of A. francisci and E. tau, however, are quite different.

Paleontological data suggest a common origin of Amerhippus, Sussemiones, and 'stilt-Iegged' equids during the late Blancan. Old World hemiones seem to have differentiated later. 

Record of life and works of Henri Menu, French zoologist, contributor to the knowledge of living and fossil bats. 

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. 

Abstract
 The validity of Propachynolophus Lemoine, 1891, supposedly an intermediate between Hyracotherium Owen, 1841 and Pachynolophus Pomel, 1847, has been questioned for a long time. A detailed analysis of features on which this genus is based further supported by a formal cladistic analysis demonstrates that Propachynolophus is not a valid taxon. The type species, “Propachynolophus gaudryi Lemoine, 1891” shall be assigned to Propalaeotherium Gervais, 1849, under the new combination Propalaeotherium gaudryi (Lemoine, 1891). “Pachynolophus maldani Lemoine, 1878”, later assigned to Propachynolophus, typifies the new genus Orolophus, under the binomen Orolophus maldani (Lemoine, 1878). The other referred species, “Propachynolophus levei Hooker, 1994” and “P. remyi Checa-Soler, 1997” are poorly documented, and both species shall be provisionally referred to as “Hyracotherium” levei (Hooker, 1994) and “Hyracotherium” remyi (Checa-Soler, 1997), pending new discoveries.