Tommotiids are a geologically short-lived group of early skeletal fossils, most abundant in the Lower Cambrian. Redescriptions of a lapworthellid (Lapworthella rete Yue, 1987) and a tannuolinid (Tannuolina zhangwentangi Qian and Bengtson, 1989) from the Jiulaodong Formation, Maidiping, Sichuan, augment previous accounts. Lapworthella rete approaches the L. dentata–L. schodackensis complex, but has a prominent external pattern of polygons that probably represent imprints of epithelial cells. Description of Tannuolina zhangwentangi emphasises ultrastructural features, including the mode of growth, development of canals, and possible epithelial imprints on the interior surfaces. Data on size variation of epithelial imprints in tommotiids are reviewed to try to infer possible variations in genome content of the cells. In addition, poorly preserved lapworthellids (Lapworthella sp.) are described from the Qiongzhusi Formation, Meishucun, Yunnan.

A single specimen of Ratcliffespongia wheeleri n. sp. from the upper part of the Middle Cambrian Wheeler Shale in the Drum Mountains of western Utah shows two distinct skeletal layers in the limonite-replaced fragment. The probable inner layer has large, circular to elliptical parietal gaps, some of which are aligned horizontally(?); gaps are outlined by long rays of hexactine-based spicules in irregular orientation and spacing. The probable outer layer has several ranks of stauracts in regular reticulation and ranking, all at approximately 45 degrees to the probably horizontal direction. The specimen is part of a probably shallow turbidite-transported assemblage from the margin of the House Range embayment.

An interval of the Early to Middle Pleistocene history of the California Borderland was assessed using multivariate analysis of foraminifera from the Santa Barbara Formation at Bathhouse Beach, Santa Barbara, California. A census of 93 species of benthic foraminifera and nine species of planktonic foraminifera was compiled from 11 samples from the shelly marls, silts, and sands of the lower member. Most species of benthic foraminifera are rare and only 38 species comprise one percent or more of the population in one or more samples.

Paleoenvironment of the sea floor was determined based on benthic foraminifera. R-mode cluster analysis defined five associations which are similar to those of the present-day banks and terraces of the California Borderland. Q-mode cluster analysis grouped samples into four biofacies which characterize shallow banks near 50 meters water depth and off-shore ridges and deep banks averaging 150 meters water depth. The stratigraphic succession of biofacies indicates two transgressive cycles separated by an apparent disconformity between 7.5 and 8.9 meters above the base of the section (between samples 3 and 4).

Paleoceanography of surficial waters was interpreted from planktonic foraminifera. Paleotemperature was assessed from the proportion of sinistral to dextral morphs and from the proportion of encrusted, compact morphs to reticulate, globular morphs of Neogloboquadrina pachyderma. The coiling morphs show a warm interval from the base of the section to about 12 meters (between samples 5 and 6), and a cooler interval from about 12 meters to about 24 meters (between samples 10 and 11), and an interval of intermediate paleotemperature in the topmost sample of the section. Changes in the planktonic assemblage do not coincide with the transgressive cycles inferred from the benthic biofacies.

The Bathhouse Beach section can be placed chronostratigraphically based on planktonic foraminiferal coiling shifts and strontium isotopic data. The isotopic age range of 400 to 900 Kyr brackets the 600 Kyr age assigned by Lagoe and Thompson (1988) to the Neogloboquadrina pachyderma coiling dominance interval CD9/CD8 boundary which occurs midway in the section, between samples 5 and 6.

The Lower Pennsylvanian (Morrowan/Atokan) portion of the Fountain Formation in the Manitou Springs, Colorado, area commonly has been interpreted as a subaerial alluvial fan. However, approximately 12 marine-nonmarine cycles, each represented by a discrete progradational sequence, have been recognized within the lower third of the Fountain Formation in this area. The typical cycle is composed of six lithofacies: 1) transgressive-lag conglomerate; 2) offshore mudstone; 3) hummocky crossbedded sandstone; 4) planar crossbedded granular sandstone; 5) low-angle, crossbedded, coarse-grained sandstone; 6) lenticular conglomeratic sandstone. Only lithofacies 6 is nonmarine (alluvial) in origin. Two diverse trace-fossil assemblages (totalling 18 ichnogenera and 20 ichnospecies) within the Fountain Formation are restricted to the marine portions of the section, or to those portions within 1 m below marine-deposited strata. The assemblage includes Arenicolites carbonarius, ?A. ichnosp., Aulichnites parkerensis, two types of Chondrites, ?Conostichus broadheadi, ?Crossopodia ichnosp., Curvolithus manitouensis (ichnosp. nov.), Eione ichnosp., Lockeia ichnosp., Macaronichnus segregatis, Palaeophycus heberti, Palaeophycus striatus, Planolites beverleyensis, Psammichnites plummeri, Rhizocorallium irregulare, ?Skolithos ichnosp., Taenidium serpentinum, ?Teichichnus ichnosp., ?Thalassinoides ichnosp., ?Zoophycos ichnosp., and several unnamed traces.

Trace fossils in the Fountain Formation can be used as indicators of sedimentary processes (e.g., rates of deposition, energy regime). Trace-fossil composition changes along a roughly south-to-north, nearshore-to-offshore gradient, generally reflecting increased influence and duration of normal-marine sedimentation. Ichnotaxa present and their distributions within marine strata in the lower part of the Fountain Formation suggest that they belong to the Curvolithus ichnoassemblage, which has been shown to indicate high sedimentaiton rates in relatively nearshore shelf settings. The Curvolithus ichnoassemblage can be subdivided into Macaronichnus-dominated and Curvolithus-dominated parts. Macaronichnus-dominated portions of the Fountain Formation indicate generally higher wave-energy sedimentation as compared with Curvolithus-dominated portions.

Ten new species of benthic foraminifera are described from the early to middle Pleistocene Bathhouse Beach locality of the Santa Barbara Formation, Santa Barbara, California. The new taxa include Glabratella luxuribulla n. sp., Rectobolivina ruida n. sp., Homalohedra jungocostata n. sp., Homalohedra quasilineata n. sp., Pytine lemniscata n. sp., Lagena complurecosta n. sp., Lagena compressacosta n. sp., Cerebrina adamanta n. sp., Fissurina artolabiata n. sp., and Fissurina infragilella n. sp. Palliolatella immemora is proposed as a replacement name for the primary homonym Lagena neglecta Buchner, 1940.

Fourteen taxa of stromatoporoids are described from allochthonous blocks of reefal limestone embedded in siltstones of late Gedinnian to Siegenian age. The fauna is a mixture of genera that characterize Ludlovian–Gedinnian rocks (Actinodictyon, Parallelostroma, Syringostromella) and those that characterize Emsian–Eifelian rocks (Atopostroma, Anostylostroma, Habrostroma, Syringostroma). The following new species are described: Gerronostroma franklinense, Gerronostroma nivale, Actinodictyon venustum, and Syringostromella praecox. The new genus Belemnostroma with type species B. hastatum n. sp. is established for stromatoporoids with the basic structure of Anostylostroma but penetrated by large, rodlike megapillars. Species with long coenosteles are excluded from Stromatopora on the basis that they are not congeneric with the type species and many species assigned to Ferestromatopora should be reassigned to Stromatopora. Previously described species of Atopostroma, Stromatopora, and Parallelostroma are recognized and redescribed.

Six species belonging to the families Proporidae and Plasmoporidae occur in the Lower and Upper Silurian rocks of the Limestone Point and La Vieille Formations of northern New Brunswick and of the Anse à Pierre-Loiselle, La Vieille, and Gascons Formations of the Gaspé Peninsula of Québec. The three species of Propora are widely distributed but show varying faunal affinities, while both species of Plasmopora, Plasmopora logani and Plasmopora corrugata, are new and are almost endemic. Revised concepts of Propora and Plasmopora are proposed. The holotype specimen for the type species of Camptolithus was examined and confirms the genus as distinct from Propora, rather than a synonym as has been previously suggested.

The facies distribution of these corals is variable. In general, the proporids, which mostly occur in facies indicating shallow carbonate banks and patch reefs, are more restricted in distribution than the plasmoporids, which occur in these facies and also in others representing a variety of open-shelf environments.

Kennardiids, members of a family of organisms that bore phosphatic sclerites, are present in Antarctica; previously, they had been found only in Australia. This new occurrence reinforces the concept of a faunal province shared between the continents during Early Cambrian time. Although the two known genera of kennardiids, Dailyatia Bischoff and Kennardia Laurie occur in Antarctica and Australia, no species are common to both continents.

Dailyatia is interpreted as having had tightly fitting sclerites that armored a bilaterally symmetrical, bipolar body; two alternative reconstructions are presented. Taxa include two new species, Dailyatia braddocki and Dailyatia odyssei, and two unnamed species of Kennardia.

An ichnofossil formed by an organism that preferentially burrowed the micritic sediment filling corallites of tetradiids has an axial passage that may be filled with sediment or calcite spar and a surrounding affected zone of concentric structure formed by the alignment of grains. More than one such burrow may occur in a single corallite. A larger ichnofossil that destroyed both septa and walls of the corallites is associated with the smaller ichnofossils.

A single specimen of the new sponge, Raphidonema indica n. sp., is the first Eocene sponge to be reported from India. It was collected from the Fulra Limestone Formation at Lakhpat, Kutch, India. The undulating, cup-like sponge is most similar to R. farringdonense (Sharpe, 1854), but the Indian species has a clustered, mounded excurrent system and numerous tangential canals on the upper, exhalant surface. Skeletal tracts in Raphidonema indica are 0.4–0.5 mm in diameter, in walls that are generally 12–14 mm, but range up to 18 mm thick.

Blastulospongia is an enigmatic siliceous fossil with affinities proposed amongst both the sphinctozoan-grade sponges and radiolarians. Blastulospongia polytreta n. sp. extends the record of this genus into the Lower Cambrian (Shuijingtuo Formation) and represents its first occurrence in China (Taishanmiao section, Hubei Province). It differs from previously described species in size and pore spacing. The first evidence for benthic attachment is presented. A relationship with sphinctozoan-grade sponges is considered unlikely, but firm support for a place in the radiolarians is lacking.

Microstructural and compositional data support the view that the skeletons of rugose corals consisted of (probably high-Mg) calcite, unlike the skeletons of scleractinian corals which are predominantly aragonitic. Total transformation of a late Permian rugose coral skeleton into neomorphic calcite and a significant trace element composition, however, show that aragonite was present in some Rugosa shortly prior to the extinction of this order. This finding sheds new light on the possible phylogenetic relationship between Rugosa and Scleractinia, which still possess a different mode of septal insertion and remain separated by an as yet coral-free interval in the Lower Triassic.

A new family, Bimuroporidae, is proposed for a clade of Ordovician trepostome bryozoans. The family is united by several characteristics, including a zooidal ontogenetic progression from mesozooid to autozooid and an integrate wall structure. Discriminant and cladistic analyses of colonies from the Ordovician Simpson Group outcropping in the Arbuckle Mountains and Criner Hills of south-central Oklahoma permit the recognition of eight species belonging to this family. Four species assigned to the new genus Bimuropora are described: B. dubia (Loeblich), B. pollaphragmata n. sp., B. conferta (Coryell), and B. winchelli (Ulrich), as well as four species assigned to the genus Champlainopora Ross: C. chazyensis (Ross), C. ramusculus n. sp., C. pachymura (Loeblich), and C. arbucklensis n. sp.

Three remarkable fossil medusoid hydrozoans (Plectodiscus latinautilus n. sp.) with disc, topsail, and pendant tentacular appendages were recovered from the latest Late Devonian beds of the Sappington Member of the Three Forks Formation in the Gallatin Range, southwest Montana. This is the first velellid reported from a Paleozoic beach paleoenvironment. Top and underside patterns of these chondrophorine velellids display well-preserved casts and mold imprints in fine siltstone. Outlines of the circular disc and the profile of the wide sail and tentacular structures embedded in soft tissue can be recognized.

These floating colonial animals were moved along the southeast shores of the Sappington Basin during a time of eustatic sea level lowering and regression in a tropical setting. Colonies were washed up on the upper beach where they were stranded in the bubbling swash left behind by the surf. The foreshore was constructed of tabular, planar cross-bedded, seaward-dipping, foreset accretionary beds which contain parallel laminations and lime-coated grains. Bedding is inclined 17° to 24° seaward.

Dictyosponges from the Chesteran Bangor Limestone document the first known occurrence of these hexactinellids in Mississippian rocks of Alabama and their discovery adds information to the worldwide impoverished record of Lower Carboniferous Porifera. The sponges are generally fragmented and occur in marine, cross-bedded, sandy limestone and sandstone channel-fill lenses that occur up to 12 m above the base of the formation, above the Hartselle Sandstone. The reticulosid dictyosponges Dictyospongia(?) sp., Clathrospongia bangorensis n. sp., Clathrospongia(?) sp. A, Clathrospongia(?) sp. B, Thamnodictya(?) radiata n. sp., and Phragmodictya rugosa n. sp. are described. Previously, the lyssacinosid(?) hexactinellid Pileospongia lopados Rigby, Keyes, and Horowitz, 1979, was described from this region, from the slightly older Chesteran Monteagle Limestone, and its occurrence in the Bangor Limestone is the youngest yet discovered. In addition to the above hexactinellids, the demosponge Belemnospongia parmula Rigby, Keyes, and Horowitz, 1979, is questionably represented by a single impression in fine-grained sandstone of the Bangor Limestone.

Two species of solitary rugose corals occur in Late Ordovician strata of the St. Lawrence Lowland. Grewingkia canadensis (Billings, 1862) appears in the upper part of the Nicolet River Formation (upper St. Hilaire Member) and is far more common in the overlying Pontgravé River Formation. A single specimen of Streptelasma divaricans (Nicholson, 1875) is known from the Pontgravé River. Their presence confirms that this area is situated within the Richmond Province and that the upper Nicolet River, as well as the Pontgravé River, is Richmondian in age. Solitary Rugosa were introduced to this biogeographic province during an early Richmondian transgression, marked in the upper Nicolet River Formation by a coarser clastic interval. That event permits correlation between the St. Lawrence Lowland in the eastern part of the Richmond Province and the North American type Upper Ordovician (Cincinnatian Series) of the Cincinnati Arch region in the western part of the province.

A comparative morphologic, paleoecologic, and biostratinomic analysis of solitary corals indicates that normal, low-energy conditions were interrupted occasionally by high-energy events (probably storms) during deposition of the upper Nicolet River and Pontgravé River Formations. Water depth increased northwestward in the St. Lawrence Lowland area. Deposition of these siliciclastic prodelta to delta front sediments was generally continuous and the sedimentation rate was usually high because of rapid basin subsidence and comparatively close proximity to the Taconic Mountains. In the western part of the Richmond Province, farther from the source area, carbonate as well as clastic sediments accumulated, periods of nondeposition were more frequent, and the sedimentation rate was relatively low. Corals disappeared from the St. Lawrence Lowland area during the Richmondian, when delta top facies of the Bécancour River Formation succeeded the Pontgravé River Formation due to a glacio-eustatic regression and progradation of the Queenston Delta.

The genus Bimuria Ulrich and Cooper, 1942, is a biogeographically important member of middle and late Ordovician brachiopod faunas of the Callahan–Gazelle area in the eastern Klamath Mountains of northern California. In middle Ordovician deposits the genus is widespread and ranges from Nevada in the west to southwestern Siberia in the east; however, in late Ordovician beds it was previously known only in Sweden and Northern Ireland. In addition to the northern California occurrence reported here, new late Ordovician occurrences are also noted in east-central Alaska–Yukon Territory and Northwest Territories. Three species of Bimuria are described, including the new species, B. californiensis.

A preliminary survey of species described in the literature suggests that the ratio of the length of the dorsal adductor field to the length of the elongate area in the brachial valve decreases from middle to late Ordovician species, and thus may be of biostratigraphic value.

The level of colony integration in tabulate corals is the degree of colony unity with respect to behavior, physiology, and development of individual organs or organ complexes within colonies. These are difficult to assess in fossils, but the level of colony integration can be tested by analyzing ontogenies and astogenies of two common Paleozoic tabulate coral groups, favositids and heliolitids. Favositids have been previously interpreted as highly integrated colonies, but results of the present examination suggest that the level of colony integration in favositids was rather lower than hitherto assumed. The ontogenies and astogenies in favositid colonies are not correlatable; thus, the significance of ontogenetic and astogenetic variations for systematic and phylogenetic resolution in favositids is difficult to assess at present. In contrast, astogenetic developmental sequences are recognized in heliolitids. Ontogenies in heliolitids were subordinated to the astogeny of the colony. This is closely related to the high degree of colony integration with respect to behavior and physiology of individual organs or organ complexes within colonies. Individual corallites were well linked and coordinated so that the whole colony could have functioned as a single individual. As a result, evolution in heliolitids operated at the colony level and by heterochronic (and other) modifications of astogenies rather than of ontogenies.

Five species of rostroconchs are known to occur in six Mississippian units in Ohio. Aphelakardia alternistriata (Herrick) n. gen. and Hippocardia herricki n. sp. are present in the Meadville and Wooster Members, Cuyahoga Formation (Osagean). ?Hippocardia sp. occurs in the Meadville Member. Pseudomulceodens cancellatum (Hyde) n. gen. is known from the Byer Member, Logan Formation, and Wooster and Blackhand Members, Cuyahoga Formation (Osagean). Bransonia hydei n. sp. occurs in the Maxville Limestone (Chesterian). An unidentified taxon occurs in the Allensville Member of the Logan Formation.

Two new conulariid species, Conularia clarkei Babcock and C. paraguayensis Babcock from the Vargas Peña Shale, are the first Silurian conulariids to be described from Paraguay. They increase to three the number of Silurian species to be described from South America. The concept of Conularia Miller in Sowerby, 1820, is emended. It includes as junior synonyms Conularia (Plectoconularia) Bouček, 1939, Diconularia Sinclair, 1952, and Yangoconularia Xu and Li, 1985. The age of the Vargas Peña Shale has long been disputed, but conclusions based on organic-walled microfossils indicate an Early Silurian (Llandoverian) age for the unit.