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.

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.

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 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.

Lower and Middle Devonian brachiopod-dominated communities of Nevada are numerous (46) and most are positioned on or adjacent to the carbonate-platform foreslope or ramp. Level-bottom community chains are fundamentally different from community associations that are interrupted by a platform margin. All communities require relative abundance data of constituent species for recognition. These communities prove to be endemic to the Nevada-southeastern California area, even though faunal similarities with distant regions in North America can be recognized. Analogous communities, the same age as comparable communities in Nevada, differ in overall specific content and in relative abundance of diagnostic species. Identification of analogous communities requires recognition of common physical environments (first) and faunal similarity (second). Groupings of communities based on presence-absence data of key species and genera are not meaningful.

Biofacies boundaries sited on carbonate-platform foreslopes separate community associations and also act as filter boundaries for faunal realms. The platform and peripheral biofacies thus delineated are also realms, a pattern that is repeated by different organisms from Cambrian to Cenozoic. Biofacies boundaries shift in concert with large-scale sea-level fluctuations. During platform emergence, most faunas are peripheral and therefore cosmopolitan. Transgression initially forms small, isolated epeiric seas populated from offshore, and endemic faunas evolve. Increased transgression merges epeiric seas and faunas, reducing provinciality and diversity through competition. Regression results in extinctions in proportion to its rate and the area involved. The cycle repeats.

The hermanni-cristatus conodont Zone is replaced with the name hermanni Zone. The disparilis Zone is divided into Lower and Upper Subzones. The norrisi Zone is proposed at the top of the Middle Devonian.

The rhynchonellid genus Ptilorhynchia Crickmay and the terebratulid genus Sellithyris Middlemiss are described from Mexico for the first time. This is the first formal description of Sellithyris from the American Continent. Ptilorhynchia (Proteorhynchia) imlayi n. sp. is described from the late Aptian of the La Penã Formation, Coahuila. “Rhynchonella’ durangensis Imlay from the Valanginian of the Carbonera Formation, Durango, is assigned to Ptilorhynchia (Proteorhynchia). “Terebratula’ coahuilensis Imlay from the Valanginian Barril Viejo Formation, Coahuila, is referred to Sellithyris. Sellithyris coahuilensis indicates close links with contemporaneous Valanginian faunas of southern Europe. During the early Early Cretaceous Sellithyris had a fairly restricted latitudinal and broad longitudinal distribution (Tethys and its extension across the opening Central Atlantic Ocean). Ptilorhynchia (Proteorhynchia) in Mexico is significant as the first low-latitude record for Ptilorhynchia. Other Lower Cretaceous records are from northern and southern high latitudes, previously interpreted as a bipolar distribution. It is suggested that Ptilorhynchia had a Boreal-East Pacific distribution with Ptilorhynchia (Proteorhynchia) being a low-latitude Early Cretaceous offshoot. The genus may prove to be pandemic. Proteorhynchia Owen is regarded as a subgenus of Ptilorhynchia.

Groomodiscus rossi n. gen. and sp., a bellerophontacean from the Ordovician of Nevada that uncoiled at maturity, is described and placed in the Gastropoda. The deep notch or sinus of the shell is interpreted to have functioned the same as a deep slit, and the new genus is placed within the tropidodiscinids. Uncoiling and thickening of the shell in the mature stage of growth is probably an indication of a fundamental change of life style to a sedentary mode. Fragmentary specimens of the final, uncoiled portion of the whorl resemble the apertural portion of hyoliths. From a functional viewpoint, compressed planispiral shells are concluded more likely to be gastropods than monoplacophorans.

Encrinurinae from the Ludlovian Brownsport Formation in west central Tennessee include Balizoma ramskoeldi n. sp., Fragiscutum glebale Campbell, 1967, and Mackenziurus sp. Balizoma ramskoeldi is most similar to Ludlovian species in England and Gotland. The discovery of F. glebale in Tennessee extends the geographic range of this species, known also from the correlative Henryhouse Formation in Oklahoma. Fragiscutum is an eastern/southern Laurentian endemic; Balizoma is of Wenlockian–Přidolían range, with its most widespread Euramerican distribution in the Ludlow. The stratigraphic range of Mackenziurus is extended into the Ludlow.

Hollinacean and kirkbyacean ostracodes are rare to abundant components of the ostracode faunas in the Pennsylvanian marine units of the Appalachian Basin. The diversity of these two groups appears lower in the Appalachian Basin than as reported from the Eastern Interior Basin. Thirty-six taxa, nine hollinelliid and 27 kirkbyiid, are identified. Three new species, Amphissites (Amphikegelites) sohni, Kegelites cooperi, and Kirkbya causa, are proposed.

Kirkbyaceans from the Morrowan–Atokan portion of the section compare favorably with those described from the Eastern Interior Basin. The Shleesha rothi Zone of the Eastern Interior Basin can be recognized in the Appalachian Basin, comprising Morrowan and Atokan units. Desmoinesian units in the Appalachian Basin contain many taxa extending up from the Atokan, but several new forms appear. Of the latter, Kegelites cooperi is the most diagnostic species and is the name bearer for the Kegelites cooperi Zone. Missourian–Virgilian faunas are significantly different from those in the Desmoinesian, but are not separable from each other. These units are grouped together into the Kegelites dattonensis Zone.

The Early Carboniferous (Mississippian) cyathocrinine cladid crinoid Barycrinus, which is common in North America, has hitherto been recognized from Britain only on the evidence of one species, Barycrinus ribblesdalensis (Wright), based on rare dorsal cups. Barycrinus sp. pluricolumnals and plurimeres are common in the Salthill Cap Beds (Chadian), Salthill Quarry, Clitheroe, Lancashire, but are not conspecific with B. ribblesdalensis. Salthill ossicles are never preserved as individual columnals due to the relative weakness of the intermeric versus the longitudinal ligaments.

Recent studies of drill-cores and outcrops have resulted in the discovery of previously unknown, taxonomically diverse, graptolite faunas in the late Middle (Mohawkian) and early Late Ordovician (Cincinnatian) strata in the Cincinnati region, the type area of the Cincinnatian Series. These faunas contain several zonal indices and other biostratigraphically important species that are used for close correlation with the standard graptolite zone succession in New York and Quebec. The new data show that the base of the Cincinnatian Series in its type area is near the middle of the Climacograptus (Diplacanthograptus) spiniferus Zone. Significantly, about a dozen Cincinnati region graptolite species are shared with apparently coeval strata in the standard Australian graptolite zone succession in Victoria, and this key faunal evidence indicates that the base of the typical Cincinnatian corresponds to a level near the middle of the Climacograptus (Climacograptus) baragwanathi Zone (Ea2) of the Eastonian Stage. This represents a considerable revision of some recently published correlations of the basal Cincinnatian in terms of the Australian graptolite zone succession.

Detailed qualitative analysis of the Pa element and multielement analysis emphasizing the associated Pb element have led to the present revision of the Frasnian species of Ancyrognathus. Diagnostic characters of the Pa element, such as the platform outline, carinal pattern, and shape of the pit, as well as salient features of the Pb element, are the basis of this revision. As a consequence, the restriction in the definition of A. triangularis, formerly a heterogeneous concept including several discrete species, has in turn led to the recognition of a substantially increased number of species of Ancyrognathus.

The lowest occurrence of Ancyrognathus primus is used here to delimit the base of Zone 6 of the Montagne Noire Frasnian sequence. The exact relationship of the Montagne Noire zonation to the published standard zonation is problematical. For example, the base of the range of A. triangularis is possibly above the zone for which it is the nominal species in the standard zonation. Two new species are named herein, A. coeni and A. seddoni, both of which have been widely illustrated in the literature, and three new species are recognized in open nomenclature.

A fragmentary tyrannosaurid skull and postcranial skeleton from the Kirtland Shale of northwestern New Mexico is the most complete specimen of a carnivorous dinosaur known from these strata. The specimen is identified as Aublysodon cf. A. mirandus on the basis of its narrow frontals, V-shaped frontal-parietal suture, and nondenticulate incisiform premaxillary tooth. The D-shaped cross section of the premaxillary tooth, rugose postorbital, well-developed footed pubis, and proximally constricted third metatarsal confirm the assignment of Aublysodon to the Tyrannosauridae. The limb bones are gracile and similar in proportions to those of Albertosaurus; however, the tibia and metatarsals are shorter relative to the femur. The distal end of the tibia exhibits a unique medial emargination not reported in other tyrannosaurids.

The diagnosis of the shovel-tusked gomphothere genus Amebelodon has been subject to dispute since it was first established by Barbour in 1927. This dispute stems from a failure to evaluate the phylogenetic nature of two characters found in some specimens referred to Amebelodon: four lophs(ids) on some intermediate cheek teeth (M2 and M1) and internal dentinal rods within the lower tusks. These characters are considered diagnostic for the shovel-tusk gomphothere genera Platybelodon and Torynobelodon, and conflict with the traditional diagnosis of Amebelodon. Newly described specimens of Amebelodon and a detailed morphological analysis of one of the disputed characters, dentinal rods, indicate that the character states in the two shovel-tusker groups are analogous. The genus Amebelodon is rediagnosed to take into account this new information.

The rediagnosis of Amebelodon is taxonomically recognized by the designation of a new subgenus, Amebelodon (Konobelodon), which includes all Amebelodon specimens convergent with Platybelodon and Torynobelodon. A new species, A. (Konobelodon) britti, is established that includes all specimens of this subgenus from North America. Specimens from the Moss Acres Racetrack site (Hemphillian) in northern Florida are used in the description of this species.

The holotype of the errant polychaete annelid Trentonia shegiriana Pickerill and Forbes, 1978 from the Middle Ordovician Trenton Group of the Quebec City area, Quebec, Canada (see Pickerill and Forbes, 1978, fig. 1, p. 660), and subsequently figured in Boardman et al. (1987, fig. 12.4, p. 199), has now been reposited in the Division of Natural Sciences, New Brunswick Museum, Saint John, New Brunswick, with the catalog number NBMG 6501. Although the Trenton Group in this area has yielded additional annelids of uncertain affinity (Conway Morris et al., 1982), the holotype of T. shegiriana still represents the only known specimen despite a further decade of investigation. At the time of publication, a repository for the specimen was unavailable, but Dr. R. Miller, Curator for Paleontological Collections, has now arranged to receive the specimen.

Among the multitude of Silurian nautiloids described by August F. Foerste over a long and illustrious career were specimens identified by him as being in the Welch Collection of Wilmington College, Wilmington, Ohio. These were figured and discussed in a series of papers published over a several-year period (Foerste 1928b, 1930a, 1930b, 1934).

Rousseau H. Flower (1913-1988) described and figured more than hundreds of fossil taxa, collected throughout the world, during his long and colorful career (Wolberg, 1988). Most of the fossils Flower worked with remain at the New Mexico Bureau of Mines and Mineral Resources (NMBM&MR). Not surprisingly, given his interests in worldwide distributions of cephalopods and other groups, a rather small proportion of the fossils Rousseau worked with throughout his career were collected in New Mexico; a large proportion of the fossils actually belong to other institutions. The NMBM&MR continues to receive requests for published specimens and is making every effort to return loan material. The NMBM&MR also believes that the professional community would be best served by maintenance of the Flower/NMBM&MR fossils in a national repository. It was Rousseau's wish that the Smithsonian Institution/U. S. National Museum serve as one of the repositories of the NMBM&MR collections.

The trilobite species Cryphaeus nicholsi Roy, 1929, was based on two pygidia from a Devonian red sandstone bed at Patacamaya, La Paz Department, Bolivia. Study of the syntypes (Field Museum of Natural History, Chicago) reveals that two well-known species are represented.

Although many of the surviving lineages of sea stars appeared during an early Mesozoic radiation of the class and have undergone limited change since then, they have left a very poor fossil record, particularly in the Mesozoic of North America (Blake, 1981). This record from the Late Cretaceous of Alberta is made more significant by the fact that it is apparently only the second occurrence of a member of the family Astropectinidae in the Cretaceous of North America; Lophidiaster silentiensis was described by McLearn (1944) from the Lower Cretaceous (Albian) Hasler Formation, from a now-submerged locality on the Peace River in northern Alberta. All previously recorded fossil sea stars from the North American Cretaceous are representatives of the family Goniasteridae.

The Edaphosauridae is an important family of primitive synapsids that includes the oldest known terrestrial herbivorous vertebrates. Until the recent description of a new, primitive edaphosaur from the Upper Pennsylvanian of Kansas (Reisz and Berman, 1986), the herbivorous Edaphosaurus was the only known member of the family. Accordingly, fragmentary edaphosaurid materials from Europe and North America had been assigned to Edaphosaurus on the basis of the characteristic neural spine morphology.