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Fungal hyphae, unicellular algae, and filiform prokaryotic inclusions are the most abundant microfossils of the Cretaceous amber of Schliersee (Bavaria, southern Germany). These prokaryotes are described as Leptotrichites resinatus new genus and species, and interpreted as sheathed bacteria with similarities to the extant genus Leptothrix Kutzing, 1843. However, the micromorphological and microanalytical features of this new species do not correspond entirely with those of the modern sheathed bacteria. Previous interpretations of these inclusions as filiform cyanobacteria, algae, and fungi have to be revised. Together with tbeir numerous syninclusions, mainly fossil ciliates, testaceans, and microalgae, these prokaryotes belonged to a Cenomanian limnetic microcenosis of water bodies, such as ponds close to the resin-producing trees. Actualistic paleontological experiments reveal how these soft-bodied microorganisms could have been embedded in resins.

A single bed at the base of the Jordan Sandstone in a road cut at Arcadia, Wisconsin, yielded an undescribed Late Sunwaptan (Saukia Zone) trilobite fauna that includes at least four species from the families Dikelocephalidae Miller, 1889 and Eurekiidae Hupe, 1953. Arcadiaspis bispinata n. gen. and sp. is a distinctive eurekiid that is characterized by paired occipital and thoracic axial spines, long genal spines, and a nonspinose pygidial margin. Other genera present are the dikelocephalids, Dikelocephalus Owen, 1852 and Calvinella Walcott, 1914, and the eurekiid, Eurekia Walcott, 1916. Type material of Calvinella spiniger (Hall, 1863) is illustrated photographically for the first time. A new eurekiid species, Corbinia burkhalteri from the Fort Sill Formation, Oklahoma, is also described.

A new lyssacinosan hexactinellid, Rossella bromleyi n. sp., is described from the Upper Cretaceous of Arnager Pynt, Bornholm (Denmark). The sponge shows a cup-shaped form with a broad, moderately dense root tuft, which contains three- and four-rayed orthotropal anchors characteristic for Rossella. The skeleton is composed of bundles of diactines, hexactines of two orders, and pentactines. Diactine bundles are mainly in the growth direction or diagonal to it. Prostalia lateralia are pentactines with the paratangential rays protruding beyond the outer surface of the sponge body. Hypodermalia are absent.

The lower part of the Shinarish Formation of Djebel Sinjar, northwest Iraq, yields an ammonite assemblage of Upper Campanian age dominated by heteromorph taxa: Nostoceras (Nostoceras) ellipticum new species, N. (N.)(?) budanyi Foldyna and Vasicek, 1977, N. (N.) cf. hyatti Stephenson, 1941, Exiteloceras(?) etequense Lewy, 1969, Didymoceras sp., unassigned nostoceratid fragments, Solenoceras reesidei Stephenson, 1941, and Lewyites oronensis (Lewy, 1969), together with the normally coiled Hauericeras (Gardeniceras) sp. Several of the species present also occur in the lower part of the Mishash Formation in Israel, in the Gulf Coast region of the United States, and as rarities in the U.S. Western Interior. All occurrences are compatible with an Upper Campanian attribution.

The peridiniacean dinoflagellate cyst Manumiella seymourensis new species described herein characterizes Maastrichtian shallow marine sediments cropping out on Seymour Island, northeastern Antarctic Peninsula. It dominates palynological assemblages throughout the lower Maastrichtian (and possibly uppermost Campanian) to lower upper Maastrichtian part of the Lopez de Bertodano Formation. Despite its superficial similarity to some other southern mid to high paleolatitude Campanian-Maastrichtian species, M. seymourensis represents a discrete, biostratigraphically useful population of peridiniacean cysts. Its morphology and size parameters remain consistent throughout almost all of its stratigraphic range, equated with relatively stable environmental conditions throughout much of the Maastrichtian in the James Ross Basin. Morphological variations, equated with environmental change, are apparent in specimens in the lowermost and uppermost parts of its range.

A new species, Bananogmius ellisensis n. sp., known only from the holotype, is described from the Blue Hill Shale Member (Upper Cretaceous, middle Middle Turonian) of the Carlile Shale Formation in western Kansas. The skull and anterior portion of the specimen is well-preserved and was subjected to little post-mortem deformation suggesting rapid burial. The nearly complete skull shows three characters that separate the fish from other species of Bananogmius: a straight, rather than ventrally curved dentary, a narrow band of teeth on the dentary that does not extend onto its lateral side, and a cylindrically-shaped articular condyle of the quadrate. The uncompressed preservation of the skull reveals a pair of long structures ventral to the mandible that are also found, but not described for some other Bananogmius species. based on the positions of muscles in extant teleosts, these structures are most likely the mineralized protractor hyoidei muscles. Furthermore, these structures may be homologous with ventral structures found in Tselfatia. The presence of Bananogmius adds a new ecological component to the Blue Hill Shale fauna.

Large, shallow, epeiric seas and adjacent lagoons such as those described herein likely played a significant role in moderating Jurassic coastal and continental climate. Jurassic (Bathonian) ocean surface temperatures in Scotland have been calculated from [[Delta].sup.18][O.sub.(CaC[O.sub.3])] values of a suite of the oldest well-preserved fish otoliths analyzed to date. Otolith [[Delta].sup.18]O values range from -4.7[per thousand] to -1.9[per thousand] (Vienna Peedee belemnite, VPDB), while [[Delta].sup.13][C.sub.(CaC[O.sub.3])] values vary from -5.4[per thousand] to + 1.5[per thousand] (VPDB), representing the oldest stable isotopic record of paleodiet, paleoecology, and fish migration to date. Using a global ocean [[Delta].sup.18][O.sub.([H.sub.2]O)] value of -1.0[per thousand] (Vienna standard mean ocean water, VSMOW) for an ice-free Jurassic, fish species that migrated from estuarine to open marine water record time-averaged temperatures of 23 [degrees] C. Estuarine fish, assuming a similar temperature, record variation in [[Delta].sup.18][O.sub.([H.sub.2]O)] values from -3.7[per thousand] to -2.0[per thousand] (VSMOW). That significant mixing of fresh water and seawater occurred in the Jurassic in Scotland is in general agreement with data presented by others (molluscan fauna, lithostratigraphy, paleogeography, and paleocirculation models). The [[Delta].sup.18]O values and temperatures derived in this study correspond to the meteorologic and hydrologic parameters of a mid-latitude maritime climate with low seasonality, a mean temperature of 23 [degrees] C, and abundant precipitation and humidity. The [[Delta].sup.18][O.sub.([H.sub.2]O)] values calculated from estuarine fish indicate that rainfall must have a [[Delta].sup.18][O.sub.([H.sub.2]O)] value lower than -3.7[per thousand] (VSMOW). Values of [[Delta].sup.18]O and [[Delta].sup.13]C suggest an environment hydrologically similar to that observed in the Everglades of south Florida or the estuaries of south Texas, both notable fish nurseries today. However, sea-surface temperatures were lower than those of modern Florida or Texas as evidenced by reduced evaporative enrichment of [[Delta].sup.18][O.sub.([H.sub.2]O)] values.

New dinosaur specimens from the uppermost Cretaceous of Spain represent the first record of a lambeosaurine hadrosaurid from Europe. This discovery, which consists of skull, mandible, and postcranial remains from the Tremp Basin (Lleida Province, Catalonia), is particularly unexpected because lambeosaurines are otherwise well known from western North America and central and eastern Asia. Originally named Pararhabdodon isonensis, a species previously regarded as a basal iguanodontian dinosaur, new material indicates that Pararhabdodon is in fact a primitive member of the lambeosaurine clade. The presence of lambeosaurines on the Iberian Peninsula at the very end of the Cretaceous period is likely due to vicariance rather than dispersal. The distribution of hadrosaurids suggests biogeographic differences across the European archipelago at the end of the Cretaceous.

An exceptionally large skeleton of Pentaceratops sternbergi (Ornithischia:Ceratopsia) provides for the first time an accurate impression of the body proportions in this horned dinosaur. This is the only known specimen with a skull associated with most of the postcranial skeleton. The restored skull is nearly three meters in length and is thus the largest of any ceratopsian and the largest skull thus far known in any terrestrial vertebrate. The elongate rostrum, elaborate premaxillary structure, and complex frontal and cornual sinuses demonstrate a high level of intraspecific variability in these features. Such features are therefore likely not useful in providing species-level discrimination in other chasmosaurines. The function of the intricate chasmosaurine premaxillary narial structures is probably associated with an advanced level of herbivory.

The trace fossil Ophiomorpha irregulaire Frey, Howard and Pryor, 1978, has been described chiefly from the Campanian (Upper Cretaceous) of the Book Cliffs of Carbon County, central Utah, U.S.A. Owing to the lack of type specimens and a well-defined type locality, a neotype and new paratypes are designated. Abundant material in the Spring Canyon Member of the Blackhawk Formation at Coal Creek Canyon, Book Cliffs, serves to supply a type locality and allows a more detailed description of the trace fossil than has been available hitherto, leading to an emended diagnosis. At the type locality, O. irregulaire is a shallow-tier trace fossil occurring in marine, delta-front or back-barrier, muddy, fine-grained sandstone. It probably represents the work of a crustacean deposit feeder.

The arthropod macrofauna from the Middle Member of the lithographic limestones of the Tlayua Formation, in quarries at Tepexi, Mexico, is comprised of marine and nonmarine components. Marine taxa include a new species of flabelliferid isopod, a new genus and species of an anomuran, and a new genus and species of a brachyuran crab. Remains of an arachnid and an odonate nymph represent nonmarine constituents. Previous paleoenvironmental interpretations of a restricted lagoon, with periodic episodes of marine and freshwater influences are consistent with the nature of the arthropod fauna. Isopod remains, represented only by corpses, that resemble modem ectoparasites of fishes suggest that they are directly associated with the abundant fish remains found in the quarries, either as ectoparasites that released their hosts before they died or possibly as scavengers that fed on fish remains. The next most abundant arthropods are the crabs, most of which are corpses, suggesting that this group lived in or very near to the depositional site of the Tlayua Formation. Based upon the new fossil material, the stratigraphic range for the Aeglidae has been extended to span Albian to Holocene time. Extant representatives of this family inhabit fresh water environments of South America.

Late Cretaceous dinosaur eggshell assemblages from six localities of the Tremp basin (Southern Pyrenees, Lleida, Spain) are studied and compared with those of Southern France, to correlate their temporal succession. Fontllonga 6 reveals the most diverse eggshell assemblage known so far, with seven oospecies, among which one new structural type (Pseudogeckoolithus nodosus new genus and species), a new Ratite-type eggshell (Ageroolithus fontllongensis new genus and species) and a new Prismatoolithidae are described; four other taxa are shared with Southern France. The correlation of both Spanish and French eggshell successions allows us to recognize three main periods characterised by different eggshell assemblages: a lower assemblage with Megaloolithus petralta, M. aureliensis, Prismatoolithus tenuis and P. matellensis from the French Lower Rognacian and the Spanish sites Fontllonga 6 and Moro; a middle one with M. siruguei from the Middle Rognacian and Biscarri; and a late one from the Late Rognacian with M. mummilare (from Abella and Bastus) and M. pseudomamillare (from Suterranya). Some contradictions appear when comparing results with paleomagnetism and charophyte correlations but the eggshell correlations are consistent with other stratigraphic studies.

The Campanian-Maastrichtian-aged Grande Carriere quarry near Tercis, southwest France, contains a diverse and abundant assemblage of both micro- and macrofossils from a thick sequence of well-exposed limestones. Its fauna is also a mixture of both Boreal and Tethyan Province species. Because of these two traits, the quarry provides an excellent source of information about integrated biostratigraphic events among diverse taxa, as well as providing a reference section for correlation between the two biogeographic provinces. The quarry has recently been proposed as a candidate for the Campanian/Maastrichtian boundary stratotype section, while one ammonite found there, Pachydiscus neubergicus, has been proposed as the index fossil marking the base of the Maastrichtian Stage. We have made collections of Upper Cretaceous ammonites and planktonic foraminifera from limestones exposed in, and near this site, which yield new information about the relative stratigraphic ranges of Upper Campanian and Lower Maastrichtian ammonites and foraminifera.

A new isocrinine species, Nielsenicrinus japonicus, is described from the Maastrichtian of western Kyushu, Japan. This is the first confirmed occurrence of this genus outside Europe. Three isocrinine genera, Nielsenicrinus, Cainocrinus, and Teliocrinus, have a common arrangement of ligamentary articulations in the primibrachials and secundibrachials. These taxa possibly constitute a single lineage since the Early Cretaceous through the Recent, and they were known only from Eurasia, or from Indian Ocean (Teliocrinus).

The specimen is identified as the partial cranium of a nodosaurid ankylosaur (Ornithischia: Thyreophora) on the basis of the presence of bone which is fused to the dorsal surface of the skull and has secondarily closed the upper temporal fenestrae. The only unequivocally nodosaurid material recovered from the Isle of Wight to date comes from Wealden facies, and has been referred to the genus Polacanthus; it is considered highly probable that this new skull is referable to the same genus. Despite having undergone abrasion, through post-emergence water-rolling, the skull and cranial walls have proved to be relatively informative of the general anatomy of the braincase and the neural and vascular anatomy of this part of the head. The anatomy of the braincase of most ankylosaurs (with the notable exception of the juvenile specimens of the ankylosaurid Pinacosaurus) is surprisingly poorly known, despite the relative abundance of cranial material in North American and Asian collections. The cranial neural and vascular anatomy is well shown in this specimen and enables the first detailed description of nodosaurid endocranial structures. The general form of the brain can be outlined from the structure of the endocast and the principal lobes can be identified; the majority of the cranial nerves have been identified, and a significant component of the associated vascular system is also visible. In most respects the endocast shows a neural anatomy which is common to that known in most dinosaurs. When compared to their nearest relatives, the ankylosaurid ankylosaurs (Euoplocephalus), the nodosaurid endocranial cast shows a more pronounced cerebral flexure, a forebrain which is broader and more expanded dorsally, and a more prominent cerebellum (although there is no evidence for a floccular lobe); there are minor differences in the arrangement of the cranial nerves, and the dorsal portions of the vascular system are better shown. Because of erosion, the olfactory lobes of this specimen of cf. Polacanthus are not preserved, and cannot be compared to those of ankylosaurid ankylosaurs; the latter are unusual in the strong separation of the lobes (reflected in the divergent olfactory stalks); this feature may be associated with the very complex passages within the nasal region of the skull, which are lacking in the nodosaurids described to date.

Fragmentary remains of a long-frilled ceratopsian dinosaur from the El Picacho Formation (Maastrichtian) of West Texas pertain to an undescribed form. The remains are, however, insufficient to fully characterize this species. This ceratopsian has long thick squamosals with marginal undulations, nasals lacking a discrete horncore, a thin parietal, and large trihedral epijugals. The braincase has very thick lateral walls, and a well-developed postfrontal foramen. Four species of horned dinosaurs are known from Upper Cretaceous strata of the American Southwest: Pentaceratops sternbergii, Chasmosaurus mariscalensis, Torosaurus utahensis, and the El Picacho ceratopsian. All of these belong to the subfamily Chasmosaurinae.

The skull of a new, and highly unusual crested dinosaur with an elongate rostrum is the first dinosaur to be named from the Santana Formation of NE Brazil. Irritator challengeri gen. et sp. nov was most likely a maniraptoran dinosaur, but its affinities to other maniraptorans remain to be established. Unique features for Irritator include the pattern of tooth replacement, a highly reduced supratemporal fenestra, extreme lateral compression of the rostrum and a saggital crest comprised of the frontal and parietal bones. Irritator was most probably a piscivore. A land link between South America and the dinosaurian faunal province of North America and Asia is indicated, probably via Africa. Keywords: Brazil, Lower Cretaceous, dinosaurs, biogeography.

Spiral coprolites from the Dinosaur Park Formation in the Upper Cretaceous of Alberta, Canada, have been discovered. This is the first record of spiral coprolites in the Upper Cretaceous in North America. The coprolites contain scales, vertebrae and other remains of Lepisosteus and gastropods, as well as wood fragments and small pebbles. The source animal probably lived in an estuarine environment as evidenced by the state of preservation of the corpolites and the presence of the remains of freshwater, brackish and marine organisms.

A new genus and species of heteroceratid ammonite from the Barremian of California has been identified. The type specimens are differentiated from other known members of Heteroceratidae by the rate of whorl expansion of the conch cross-section, the orientation of the spire axis with respect to the planispiral portion of the conch axis and ornamentation.

A different forelimb posture than other Cretaceous eucosmodonts was observed in a cretaceous eucosmodont multituberculate mammal skeleton with a well- conserved shoulder girdle found in Mongolia. Locomotion change seen in the skeletal structure had occurred in multituberculates and therians in the mid Jurassic period. Other postural and mobility characteristics of the specimen are similar to that of therians.

The nominal Eucrossorhinus microcuspidatus and Cretorectolobus olsoni from the Campanian Judith River Formation of Montana, correspond to teeth from juvenile and adult individuals of one single species of orectoloboid shark. The type series of the latter is heterogeneous and includes, besides the holotype, a tooth belonging to a different orectoloboid of a new generic type named Cederstroemia. This genus is unique among Orectolobiformes by comprising sharks with dental adaptations towards a strict cutting dentition. Two new species of Cederstroemia are described: C. triangulata from the Judith River Formation of Montana and C. nilsi from the early Campanian of the Kristianstad Basin, Skane, Sweden. An emended diagnosis is provided for Cretorectolobus, clarifying the dental characteristics of its members.

The Prairie Bluff Chalk of Alabama and Mississippi yields a diverse ammonite fauna of Maastrichtian age. Twenty-eight species, of which three are new, are recorded herein: Pseudophyllites indra (Forbes, 1846), Hauericeras rembda (Forbes, 1846), Pachydiscus (Pachydiscus) maconensis n. sp., P. (P.) cf. gollevillensis (d'Orbigny, 1850), P. (P.) jacquoti (Seunes, 1890), P. (P.) egertoni (Forbes, 1846), Sphenodiscus lobatus (Tuomey, 1854), S. pleurisepta (Conrad, 1857), Coahuilites sheltoni Bose, 1928, Nostoceras (Nostoceras) alternatum (Tuomey, 1854), N. (N.) mendryki Cobban, 1974a, N. (N.) magdadiae Lefeld and Uberna, 1991, N. (N.) irregulare n. sp., Glyptoxoceras torquatum (Morton, 1834), Glyptoxoceras sp. A, Glyptoxoceras? sp., Baculites lomaensis Anderson, 1958, Baculites spp. A-C, Eubaculites labyrinthicus (Morton, 1834), E. carinatus (Morton, 1834), Baculites? trabeatus (Morton, 1834), Trachybaculites columna (Morton, 1834), Discoscaphites conradi (Morton, 1834), D. gulosus (Morton, 1834), Jeletzkytes criptonodosus Riccardi, 1983, Trachyscaphites alabamensis n. sp., and T. yorkensis (Stephenson, 1941). One genus, Trachybaculites, is new. The bulk of the fauna can be referred to a Discoscaphites conradi assemblage zone, but some elements in the fauna are significantly older.

Investigation of specimens of 'Terebratella' ovula Anderson, 1938 from the upper Lower Albian Upper Chickabally Member of the Budden Canyon Formation, Great Valley Group, California has allowed the examination of the species' internal structures by serial sectioning. 'Terebratella' ovula Anderson is now referred to the genus Dzirulina Noutsoubidze, 1945. The stratigraphic range of the genus is extended from the Hauterivian-Aptian to the Albian. The geographic range of Dzirulina is increased from central and western Europe, the Caucasus and Georgia of eastern Europe, and northern Zululand, Africa to now include northern California, North America. This represents an additional record of an Early Cretaceous brachiopod genus with a low-latitude, transatlantic distribution, most probably related to dispersal across the opening Central Atlantic Ocean.

Iberonepa romerali n. gen. and sp. is the most abundant insect species found in Lower Cretaceous (Barremian) lithographic limestones at 'Las Hoyas,' Spain. External features of this species indicate that it should be assigned to the family Belostomatidae, with a similarity to the species Stygeonepa foersteri Popov, 1971, which was found in the Upper Jurassic (Tithonian) lithographic limestones of Solnhofen. This article discusses the relation between these two species and subfamilies of the Recent Belostomatidae. The new 'Las Hoyas' species is described from adult specimens and from molts of nymphs, these differing only slightly from one another. The abundant number of specimens and the generally exceptional preservation have allowed interpretation of its probable natatory behavior on the basis of the functional morphology of the insect's legs.

The Ukhaa Tolgod region, Gobi Desert, Mongolia, contains a large number of vertebrate fossils from the Upper Cretaceous period. There are about 100 dinosaur articulated skeleton fossils and many nests containing the initial discovery of theropod dinosaur embryos. Skulls of almost 400 mammals and lizards and skeletons of Mononykus, a bird, have been found. Most of the mammals are multituberculates. A large number of different small vertebrates are also seen. The rapid burial of animals after sudden death in arid conditions probably after sandstorms are the reason for the excellent preservation and abundance of fossils.

Twenty-four nearly complete carapace samples were collected at three different localities of the Maastrichtian (Late Cretaceous) Cardenas Formation in San Luis Potosi, east-central Mexico. The material has been assigned to five families: the Callianassidae, Dakoticancridae, Carcineretidae, ?Majidae, and Retroplumidae. Two genera of callianassid shrimp are described, Cheramus for the first time in the fossil record. Dakoticancer australis Rathbun is reported as the most abundant crustacean element; one new genus and species of carcineretid crab, Branchiocarcinus cornatus, is erected, and a single, fragmentary specimen is questionably referred to the Majidae. The three localities reflect paleoenvironmental differences, exhibited by different lithologies, within marginal marine, lagoon environments. The record of dakoticancrid crabs in the Cardenas Formation extends the paleobiogeographic range of the family and the genus Dakoticancer. Carcineretid crabs, although not abundant, seem to have been a persistent element of crustacean assemblages in elastic environments during the Late Cretaceous of the ancestral Gulf Coast of Mexico.

Aldebarania arenitea (Astropectinidae; Asteroidea; Echinodermata) is described from the Rocky Point Member of the Maastrichtian (Upper Cretaceous) Peedee Formation of North Carolina. A turbulent, shallow-water environment is suggested by sedimentary features, a diverse marine fauna, and the morphology of Aldebarania. Aldebarania appears to be a partial ecological equivalent of living Astropecten and Luidia; however, phylogenetic relationships within the Astropectinidae are unstudied and the origin of similarities is unknown.

Newly discovered trigonioid bivalves are systematically described from the Late Albian of the Fossil Bluff Group of Alexander Island, Antarctic Peninsula. The fauna includes Nototrigonia (Nototrigonia) ponticula Skwarko, N. (Callitrigonia) offsetensis n. sp., Eselaevitrigonia macdonaldi n. sp., Pterotrigonia (Pisotrigonia) capricornia (Skwarko), and Pacitrigonia praenuntians n. sp. It represents the first Albian trigonioid fauna described from the Antarctic. It is also the first published record of the Nototrigoniinae (excluding Pacitrigonia) outside Australasia. Paleoecologically, this fauna represents the shallowest and highest energy molluscan assemblage from the Fossil Bluff Group and occurs near the base of a significant transgressive unit, the Mars Glacier Member of the Neptune Glacier Formation. The paleogeography of Austral Cretaceous trigonioids is reviewed. Endemic centers are identified in India-east Africa, southern South America, and Australasia. Only one trigonioid genus, Pacitrigonia, had its origin in the Antarctic. During the earliest Cretaceous, cosmopolitan trigonioid genera occurred in Antarctica. In the mid-Cretaceous faunal similarity of Antarctica with Australasia was strong, and in the latest Cretaceous affinity with southern South America increased.

Exogyra fossils are plentiful in Upper Cretaceous sediments in both the US Gulf Coastal Plain and the Western Interior. However, fossil specimens of this species are rarely found in chalky strata in the latter region. Reasons for this scarcity are explored by analyzing specimens from the Fairport Member and the Smoky Hill Chalk Member of the Niobrara. Analysis suggests that benthic conditions in the Western Interior Sea differed from those in the Gulf Coast, particularly in depth and salinity. These differences may have accounted for the scarcity of Exogyra in Western Interior chalky rocks.

Stirpulina saulae n. sp. is the first reported clavagellid from the Pacific Province of North America. Specimens of this clavagellid are from the Ladd Formation of the Santa Ana Mountains, Orange County, southern California. The age of these specimens is Late Turonian based upon the presence of the ammonite Subprionocyclus spp. both above and below the clavagellids in the section. These are, therefore, the oldest reported clavagellids from the western hemisphere, and they give positive support to the European Turonian reports of the genus Stirpulina. The deposits indicate an open-shelf habitat of shallow to moderate depth, and the associated fauna suggests a warm temperate to subtropical marine climate. This is consistent with the previously reported Cretaceous distribution for the group.

The Trinity Division exposures at Junction, Kimble County, Texas, yield a rich charophyte flora dominated by clavatoraceans. The presence of Atopochara trivolvis ssp. trivolvis (Peck, 1938) Grambast, 1968, and Clypeator corrugatus (Peck, 1941) Grambast, 1962, indicates an Aptian age for these strata and makes them the continental equivalent of the Lower Glen Rose. Atopochara trivolvis, whose type-material was recovered from the Trinity in a deep well in southern Texas, is known from numerous freshwater to oligohaline lakes from the Mesogean area in Europe and North Africa as well as from Cretaceous oil-bearing basins i China. Charophytes are clear indicators of supratidal environments and the abundant remains at Junction suggest a positive structural feature in this part of central Texas that might have been either an island or directly connected to the Llano Uplift.

An analysis of geomagnetic data obtained from Cretaceous submarine basaltic glass experiments reveals that the beginning and end of the Cretaceous normal superchron (CNS) period contain dipole lows. This extension theorizes that palaeointensities and reversal frequency control processes are independent of each other. The CNS period exihibits long periods of normal geomagnetic field polarity.

The Saratoga Chalk of Arkansas yields a rich ammonite fauna of 17 species, referred to the Nostoceras (N.) hyatti zone. Recognition that the northwest European N. (N.) pozaryskii Blaszkiewicz, 1980, is a synonym of N. (N.) hyatti Stephenson, 1941, and N. (N.) helicinum (Shumard, 1861) dates the zone as latest Campanian on the basis of co-occurrence with Belemnitella langei Jeletzky, 1948, in Poland. Most previous estimates of the Campanian-Maastrichtian boundary in the Gulf Coast have been drawn at too low a level, at least in terms of ammonite faunas. Elements of the N. (N.) hyatti zone fauna occur in the United States Western Interior, and show the base of the Maastrichtian there to lie above the Baculites jenseni zone.

Actinocamax cobbani, a new belemnitellid species from the middle Coniacian of Montana and Wyoming, is described, including univariate and bivariate biometric analyses. The species is stout and medium sized, lanceolate or strongly lanceolate in ventral view, and has adorally a low cone-shaped alveolar fracture. It may be granulated. It is compared to species of Actinocamax Miller and Gonioteuthis Bayle from the North American and North European paleobiogeographic provinces. The importance of various morphological characters, such as the shape of the guard and the structure of the adoral end, are discussed. The majority of the belemnitellids of the North American Province are endemic and the stratigraphic distribution is punctuated during the Late Cretaceous, suggesting short-lived migrations of populations from the North European Province.

Cretaceous and early Tertiary Pholadidae (Mollusca: Bivalvia) from the Pacific Slope of North America are rare and only poorly known. Three new species, each the earliest known Pacific Slope representative of its respective genus, are described: Barnea (Anchomasa) saulae n. sp. (Pholadinae) from the Upper Cretaceous (Coniacian and Santonian) Redding Formation near Redding, uppermost Sacramento Valley, Shasta County, northern California; Chaceia fulcherae n. sp. (Martesiinae) from three widely separated areas of outcrop represented by 1) the middle Miocene ('Temblor') Temblor Formation near Oil City and in Jasper Canyon, western Fresno County, central California, 2) the middle Miocene ('Temblor') Topanga(?) Group in the northern Santa Ana Mountains, Orange County, southern California, and 3) the upper Miocene (Wishkahan) Montesano Formation on the Middle Fork of the Satsop River, Mason County, western Washington; and Netastoma squiresi n. sp. (Jouannetiinae) from the lowest Eocene (uppermost 'Meganos') part of the Santa Susana Formation north of Simi Valley in the Santa Susana Mountains, Ventura County, southern California.

Blocks of sandy limestone dredged from the bottom of a quarry in eastern Lee County, South Carolina, contain a turritelline gastropod-dominated macrofossil assemblage, including age-diagnostic Maastrichtian ammonites. Although turritelline-dominated assemblages are common in other areas and ages, this is the first report of such an assemblage of any age from South Carolina and the first Cretaceous turritelline-dominated assemblage from eastern North America. Whereas the matrix of the turritelline layer is calcareous, the carbonate is present only as cement and the fossil assemblage did not form in a typically carbonate-dominated environment. This fact agrees with the observed absence of 'turritella limestones' in the Cretaceous. Such limestones are common in the Paleogene but absent in the Neogene. This pattern is consistent with the hypothesis that turritellines as a group have become less thermophilic since the Cretaceous.

The discovery two specimens of a flightless bird from the Upper Cretaceous of Mongolia is reported. The flightless bird was classified under a new genus and species, Mononychus olecranus. It is an avialian theropod dinosaur with a short, robust forelimb bearing a single stout claw. A carinate sternum, reduced fibula and other features mark it as a closer relative of modern birds than Archeopteryx lithographica.

Fragmentary bones and teeth of three Late Cretaceous dinosaur taxa occur along both sides of the Georgia-Alabama border, in the extreme southeastern Coastal Plain Province. The localities lie in the middle and upper Blufftown Formation, in nearshore marine deposits. Exogyra ssp. and calcareous nannofossils give a late Santonian through mid-Campanian age range. Taxa determined are: Hadrosauridae, genus and species indeterminate; Ornithomimidae, genus and species indeterminate; and Albertosaurus? sp.

Geological research in the Corsicana Formation in northeast Texas produced four previously undescribed collections of ammonites, bringing the number of these Maastrichtian ammonites found there to eleven. Similar fauna are found in northern Mexico, the Escondido Formation in Trans-Pecos Texas and the Prairie Bluff Chalk of Mississippi and Alabama. Maryland's Severn Formation and the Owl Creek Formation of Mississippi, Missouri and Tennessee have also produced elements of these fauna.