Recent sampling for larger foraminifers in the so-called Polylepidina gardnerae horizon in the middle Eocene Lisbon Formation of the Little Stave Creek section, southwest Alabama, did not produce any examples of the lepidocyclinid foraminifer Polylepidina gardnerae Cole, but several specimens of the stratigraphically younger species, Lepidocyclina ariana Cole and Ponton, were recovered. Although the P. gardnerae horizon is named on nearly all figures of this important Gulf Coast section published since 1944, preliminary research has also failed to turn up a published basis for the identification of P. gardnerae at this locality. As L. ariana and P. gardnerae are not normally found together, it is the writer's opinion that true P. gardnerae probably has not been collected from any part of the Lisbon Formation at Little Stave Creek. If it does occur, it should be found at a lower horizon than that indicated in the literature.

Discovery of fossils of the Ediacara biota near the top of the Spitzkopf Member at farm Swartpunt extends the known range of these remains in Namibia more than 600 m to near the sub-Cambrian unconformity. The fossiliferous beds occur approximately 100 m above a volcanic ash dated at 543 ± 1 Ma, and thus may be the youngest Proterozoic Ediacara-type fossils reported anywhere in the world. Fossils are preserved within and on the tops of dm-thick beds of storm-deposited sandstone at two stratigraphic levels; the environment is interpreted as open marine, generally calm but with episodic disruptions by storm waves, and probably within the euphotic zone. The presence of Pteridinium carolinaense (St. Jean), which is also known from the classic sections in Ediacara and the White Sea among others, reinforces evidence from geochronology and chemostratigraphy that the Swartpunt section is terminal Neoproterozoic in age. The new genus and species Swartpuntia germsi is a large, multifoliate frond that exhibits at least three quilted petaloids. Macroscopically, Swartpuntia resembles Pteridinium and Ediacara-type fronds such as Charniodiscus traditionally interpreted as Cnidaria, whereas microscopically it exhibits segmentation that is remarkably similar to that of the putative worm Dickinsonia. Combination of diagnostic characters of these supposedly disparate groups in a single species suggests that many species of quilted Ediacaran organisms were more similar to each other than they were to any modern groups, and provides support for the concept of the “Vendobionta” as a late Neoproterozoic group of mainly multifoliate organisms with a distinctive quilted segmentation.

Dinoflagellate cysts from the classic mid-Pliocene Coralline Crag locality of Rockhall Wood, Suffolk are described, representing the first systematic treatment of mid-Pliocene dinoflagellates from the North Sea region. The dinoflagellates broadly reflect warm-temperate surface waters whose temperatures were considerably higher than today. Two assemblages are recognized: an older assemblage (late early Pliocene or earliest late Pliocene, possibly not younger than 3.3 Ma) confined to the Ramsholt Member, and a younger assemblage (predating 2.6 Ma) confined to the overlying Sudbourne Member. Assemblages are characterized by quantitative differences and their succession indicates either: 1) slight cooling within a probable warm-temperate range; 2) a slight increase in open marine influence; or 3) a taphonomic effect perhaps related to a change in bottom currents.

Specimens have been observed using light (LM) and scanning electron (SEM) microscopy, and cyst wall ultrastructure is emphasized as a valuable but underutilized character for Neogene dinoflagellate taxonomy. Operculodinium? eirikianum Head et al. is emended and the following new taxa are proposed: Achomosphaera andalousiensis suttonensis new subspecies, Ataxiodinium zevenboomii new species, Bitectatodinium raedwaldii new species, and Operculodinium tegillatum new species. Geonettia? sp. is new to science but formal description awaits detailed analysis of tabulation.

Fusulinaceans from the flank of Northwind Ridge in the Arctic Ocean indicate that this feature is underlain by miogeoclinal upper Paleozoic strata, and that the fauna belongs to the Middle Carboniferous through Early Permian Arctic Fusulinacean Province. This province stretched from the Canadian Arctic Islands eastward to Svalbard where it merged with the similar Ural Fusulinacean Province in the western Ural Mountains. Because these provinces did not extend into Siberia, the Northwind Ridge assemblage indicates that these rocks originally were adjacent to, or a part of, the Canadian Arctic Islands Carboniferous-Permian shelf margin.

Biodiversity is the number and variability of genes, species, and communities in space and time (Norse et al., 1986; Wilson, 1988; Heywood and Baste, 1995). The fundamental question that has governed its study in modern times is Hutchinson's (1959): “Why are there so many kinds of animals?” In more recent decades, a somber subquestion has been added: How many species are dying every year (e.g., Wilson, 1992)?

Famennian (Late Devonian) echinoderm faunas are poorly known on a global basis, although reasonably diverse faunas have been reported from England and Germany. We have collected a diverse (>500 specimens representing approximately 30 taxa) Famennian echinoderm fauna dominated by blastoids and inadunate, small-calyx camerate, and flexible crinoids from the Hongguleleng Formation, Junggar Basin, Xinjiang–Uygur Autonomous Region, People's Republic of China. Taxa reported here include five new genera and six new species of blastoids along with one new genus and 19 new species of crinoids. Blastoid taxa include Junggaroblastus hoxtolgayensis new genus and species, Orophocrinus devonicus new species, Xinjiangoblastus ornatus new genus and species, Uyguroblastus conicus new genus and species, Sinopetaloblastus jinxingae new genus and species, and Houiblastus devonicus new genus and species. Crinoid taxa include Uperocrinus zhaoae new species, ?Hexacrinites species, Agathocrinus junggarensis new species, Chinacrinus xinjiangensis new genus and species, ?C.nodosus new genus and species, C. species A, C. species B, C. species C, Eutaxocrinus chinaensis new species, E. boulongourensis new species, E. basellus new species, Forbesiocrinus inexpectans new species, Deltacrinus asiaticus new species, Bridgerocrinus minutus new species, B. delicatulus new species, Cosmetocrinus parvus new species, ?Pachylocrinus subpentagonalis new species, “Decadocrinus” constrictus new species, “D.” elongatus new species, “D.” rugosus new species, “D.” usitatus new species, “D.” xinjiangensis new species, ?Graphiocrinus species, Holcocrinus asiaticus new species, and four species of inadunate crinoids that could not be assigned to genera. This fauna is more abundant and diverse than all other Famennian echinoderm faunas in the world combined, and it is critical in understanding echinoderm biogeography and evolution in the aftermath of the Late Devonian extinction event(s) prior to the Carboniferous echinoderm diversification. This echinoderm fauna is “Carboniferous” in affinity and indicates that echinoderm diversification and reradiation were well underway before the close of the Famennian.

Well-preserved polycystine radiolarians, representing a new species in the family Entactiniidae, were recovered from subtidal micrites and bioclastic micrites of the Upper Cambrian (Glyptagnostus reticulatus trilobite zone) Bitiao Formation, western Hunan, China. Confirming earlier, questionable reports of Cambrian Radiolaria, these fossils place the first appearance of the group somewhat before its Ordovician emergence as a principal constituent of the oceanic silica cycle, but long after the Proterozoic diversification of protists.

Stromatoporoids are found in the Dayville and Deansboro Members of the Coeymans Formation in central New York, where they are common to rare. The most common species present are Habrostroma centrotum (Girty) and H. microporum (Girty). Present in lesser numbers are Parallelostroma foveolatum (Girty), Atopostroma sp. 1, A. sp. 2, Coenostroma cf. C. monticuliferum (Winchell), Coenostroma sp., Habrostroma cf. H. centrotum (Girty), and Coenostelodictyon cf. C. krekovi (Yavorsky). Although previously reported from the Coeymans, Coenostelodictyon jewetti (Girty) was not found. Species identifications were based on traditional qualitative methods, supplemented by statistics. The assemblage bears affinities with Lochkovian faunas in Virginia and the Canadian Arctic.

A moderately diverse assemblage of anthaspidellid demosponges has been recovered from reef-bearing carbonate platform deposits of Early Ordovician, Tremadoc to early Arenig age, in Hubei Province. The sponges occur, in part, in the Tremadoc Fenxiang Formation and, in part, in the lower Arenig Honghuayuan Formation at several localities near Yichang, Xintan, and Liujiachang. Archaeoscyphia nana Beresi and Rigby, 1993, Archaeoscyphia pulchra (Bassler, 1927), and Archaeoscyphia minganensis (Billings, 1859) occur with the new genera and species, Jianghania yichangensis and Velellospongia adnata, and the new species Rhopalocoelia sanxiaensis and Anthaspidella lamellata. This is the first reported occurrence of Anthaspidella in Ordovician rocks of China. Great numbers of these species of fossil sponges have been found in Lower Ordovician outcrops, particularly in the eastern Yangtze Gorge area of Hubei Province.

Halkieriids are known largely from isolated sclerites, although it is understood that originally they formed the scleritomes of slug-like animals in Lower Cambrian benthic environments. The Yurtus Formation (?Tommotian–Atdabanian equivalent) of the Aksu-Wushi area, west Xinjiang, China, has yielded abundant sclerites. These are secondarily phosphatized, but show considerable detail. The sclerites can be divided into three classes: cultrates, long palmates, and short palmates; definite siculates have not been recognized. In some samples elongate to semicircular shells co-occur with the sclerites; these may derive from the same halkieriid scleritome. The external surface of the shells may bear a subdued ornamentation. The concave interior, however, is remarkable on account of a unique structure consisting of a group of nodular-like units. These may be arranged in a low cone or dispersed in a small circle. In addition to the sclerites of halkieriids and their possibly associated shells, rarer material is attributable to the related group of siphogonuchitids.

Nearly continuous cores from a 500-meter interval of upper Moscovian through post-Artinskian carbonate strata on the Finnmark Platform have yielded rich assemblages of fusulinaceans and smaller foraminifers. The fusulinaceans provide an independent time framework for evaluating stratigraphic occurrences of associated smaller foraminifers. Information derived from this study has been integrated with that from previous investigations to produce a smaller foraminiferal biostratigraphic model for the High Arctic. Kasimovian strata are characterized by occurrences of Nodosinelloides spp., Protonodosaria spp. and Hemigordius schlumbergeri. Overlying lower Gzhelian beds are identified by the appearances of Raphconilia modificata and Amphoratheca iniqua. Tezaquina clivuli and Cribrogenerina gigas first occur in upper Gzhelian strata, and Asselian rocks contain appearances of Geinitzina postcarbonica and Pachyphloia spp. Phylogenetic reconstructions suggest that the Late Carboniferous-Early Permian pseudovidalinids (Archaediscacea) derived from the Pseudoammidiscidae, as did the older group of predominantly Early Carboniferous archaediscaceans. The repeated development of similar morphologies within the two groups of archaediscaceans includes examples of both convergence and iterative evolution. The Protonodosariidae and Syzraniidae most likely evolved from an earlandiid ancestor. The syzraniids gave rise to the Geinitzinidae, which in turn gave rise to the Pachyphloiidae. As in the archaediscaceans, evolution within and among the Earlandiidae, Protonodosariidae, Syzraniidae, Geinitzinidae and Pachyphloiidae includes multiple examples of repeated patterns. Two key phenotypic developments seemingly led to bursts of diversification in different groups throughout late Paleozoic foraminiferal evolution. The acquisition of an outer hyaline or pseudofibrous wall layer was a morphologic breakthrough followed by taxonomic radiation in both groups of archaediscaceans and in the Earlandia-Syzrania lineage. The second major event was the shift from an undivided tubular morphology to uniserial morphology in both the Earlandiidae-Protonodosariidae and Syzraniidae-Geinitzinidae lines. Nodosinelloides pinardae is proposed as a new name for Nodosaria grandis Lipina, 1949 (preoccupied).

Echinus gyracanthus Eaton, 1832, was the first tentaculitid reported from North America, but the original description and illustration are vague by present-day standards. Study of the type material and topotypes from the Lower Devonian Manlius Limestone in the Town of Schoharie, New York, suggests that Tentaculites gyracanthus (Eaton) is a discrete species, but one with pronounced and remarkable intraspecific variability. Tentaculites simmondsi new species also occurs in the same unit and locality.

Mobergellans are a distinctive group of Lower Cambrian breviconic shells with a prominent set of internal scars, presumably representing sites of former muscle attachment. Shells grew by accretion and appear to have secreted primary phosphate. Here a redescription is given of mobergellans, assigned to Hippoklosma new genus, from the Khairkhan Formation (Botomian-age equivalent) of southwest Mongolia. Hippoklosma mongolica (Missarzhevsky) is bilaterally symmetrical, with five pairs of radiating structures. These are presumably homologous with the muscle scars of other mobergellans, but in contrast consist of a series of disks (herein fibroplacodes) each containing a characteristic fibrous structure capped externally by a smooth lid. The apical region of the shell is domelike with transverse segmentation. A review of other mobergellans, including new data on Mobergella holsti from Sweden and Discinella micans from New York, and possibly related taxa concludes that although their affinities are problematic, a relationship with the Mollusca may be the most plausible hypothesis on existing evidence.

Most of the specimens of Myoscolex ateles Glaessner, 1979, the most abundant soft-bodied taxon in the Big Gully fauna from the Lower Cambrian Emu Bay Shale of South Australia, preserve only the phosphatized trunk muscles, in striking contrast to the organic residues that characterize other Burgess-Shale-type biotas. This is the oldest phosphatized muscle tissue and the first thus far reported from the Cambrian. The extent of phosphatization implies a source in addition to the animal itself, and this is reflected in high levels of phosphate in the Big Gully sequence compared to other shales. The apparent anomaly posed by the extensive preservation of labile muscle tissue as opposed to the more decay resistant cuticle is explained by the role of bacterial processes in the preservation of soft tissues. New specimens of Myoscolex reveal a variable number of trunk somites with possible tergites, and flap-like appendages. There is evidence for at least three eyes on the head, and a proboscis may have been present. An annelid affinity is rejected and Myoscolex is reinterpreted as an Opabinia-like animal with possible affinities with the arachnomorph arthropods.

The type species of Parastrophinella, P. reversa, a pentamerid brachiopod from the uppermost Ordovician (Hirnantian) Ellis Bay Formation of Anticosti Island, Quebec, shows that the genus is characterized by three features: 1) a ventral median septum apically buried in a thickened valve floor, but anteriorly rising above valve floor; 2) prominent alate plates, which are homologous to brachial processes; and, 3) a pseudocruralium consisting of a dorsal median septum, which is largely buried in the valve floor posteriorly, and outer plates that are connected to the median septum via prismatic substance (with poorly developed lamellar layer at the junctions) at, or slightly above, the valve floor. These constitute criteria by which many species previously assigned to Parastrophinella are excluded from the genus. Late Ordovician species that fit the redefinition of Parastrophinella are now confined to eastern North America. The genus crosses the Ordovician/Silurian boundary without major morphologic change, and Early Silurian species of Parastrophinella occur in both eastern North America and Great Britain. In the Late Ordovician, the pentamerid fauna of North America (Laurentia) contrasted sharply with that of Baltica and Kazakhstan, where the Holorhynchus fauna was dominant. Typical elements of the Holorhynchus fauna, such as the large-shelled Holorhynchus and Proconchidium, are known only in the northern parts of Laurentia (Baffin Island, Greenland, and Kolyma), and are absent in the Hudson Bay and Williston basins and southwards.

Two samples from a large, allochthonous limestone block in the McHugh Complex of the Chugach terrane on the Kenai Peninsula, Alaska, contain species of 12 genera of Permian Fusulinina including Abadehella, Kahlerina, Pseudokahlerina?, Nankinella, Codonofusiella, Dunbarula, Parafusulina?, Chusenella, Verbeekina, Pseudodoliolina, Metadoliolina?, Sumatrina?, and Yabeina, as well as several other foraminiferans and one alga. The assemblage of fusulinids is characteristically Tethyan, belonging to the Yabeina archaica zone of early Midian (late Wordian) age. Similar faunas are known from the Pamirs, Transcaucasia, and Japan, as well as from allochthonous terranes in British Columbia, northwestern Washington, and Koryakia in eastern Siberia.

The Silurian (Wenlockian) Racine Formation of Milwaukee, Wisconsin has yielded 22 types of siliceous and silicified sponge spicules. The spicules occur in bioturbated dolomite mudstone, and they are part of a high-diversity community of small crinozoans, brachiopods, and other taxa. Siliceous desmas of the order Lithistida comprise 79 percent of recovered spicules. Siliceous triaxons of the class Hexactinellida and silicified sexiradiates of the class Heteractinida each comprise 7 percent of spicules. Eleven additional types of siliceous spicules of uncertain taxonomic affinity form 7 percent of the assemblage. No complete sponge skeletons have been observed, probably because of slow deposition and high bioturbation. The Racine spicule assemblage resembles sponge faunas of Silurian offshore deposits in the Canadian Arctic and Great Basin, which suggests moderate bathymetric relief in the Michigan Basin during Wenlockian times.

The first-described articulated Silurian sponges from Spain and Portugal include a moderate assemblage of hexactinellids and a single monaxonid demosponge. The sponges were collected from a thin layer at the top of the Cyrtograptus lundgreni-Monograptus testis graptolite biozone, in a possible volcanic ash of latest Homerian (Wenlock) age. The sponges are from southeastern Portugal and southwestern Spain in the Ossa-Morena Zone of the Hesperian Massif. The hexactinellid collection includes several specimens of the new species, Protospongia iberica, and fragments of Diagoniella species and Gabelia(?) sp. Specimens of the latter two taxa are too small for species identification. Demosponges are represented by a single described specimen of a probably new genus and species preserved as a “wreath” of monaxon spicules. Dermal and gastral layers are of very fine spicules developed over the moderately coarse, aligned, principal body spicules.

Analysis of high resolution diversity data for Mississippian corals in the western interior United States yielded mild latitudinal diversity gradients despite the small geographic area covered by samples and a large influence on diversity patterns by geographic sampling intensity (sample bias). Three competing plate tectonic reconstructions were tested using the diversity patterns. Although none could be forcefully rejected, one reconstruction proved less consistent with diversity patterns than the other two and additional coral diversity data from farther north in Canada would better discriminate the two equivalent reconstructions.

Despite the relatively high sampling intensity represented by the analyzed database, diversity patterns were greatly affected by sample abundance and distribution. Hence, some effort at recognizing and accounting for sample bias should be undertaken in any study of latitudinal diversity gradients. Small-scale geographic lumping of sample localities had only small effects on geographic diversity patterns. However, large-scale (e.g., regional) geographic lumping of diversity data may not yield latitudinally sensitive diversity patterns. Temporal changes in coral diversity in this region reflect changes in eustacy, local tectonism, and terrigenous sediment flux, far more than they do shifting latitude. Highest regional diversity occurred during the interval when the studied region occupied the highest latitude. Therefore, diversity data from different regions may not be comparable, in terms of latitudinal inference. Small-scale stratigraphic lumping of the data caused a nearly complete loss of the latitudinal diversity patterns apparent prior to lumping. Hence, the narrowest possible stratigraphic resolution should be maintained in analyzing latitudinal diversity gradients.