A low-diversity assemblage of smaller calcareous microfossils is present in the Upper Mississippian Maxville Limestone in Muskingum and Perry Counties, southeastern Ohio. Diagnostic faunal elements that suggest an early Chesterian age include the foraminifers Neoarchaediscus maxvillensis n. sp., Paraarchaediscus aff. P. Pachytheca (Petryk), Paraarchaediscus cf. P. koktjubensis (Rauzer-Chernousova), Endothyra excellens (Zeller), Endothyra bowmani Phillips emend. Brady, and attached forms. The presence of these diagnostic faunal elements in the Chesterian of Ohio significantly extends their known geographic range into the eastern Midcontinent region.

Other forms present include the foraminifers Priscella? of the group P. prisca (Rauzer-Chernousova and Reitlinger), Diplosphaerina inaequalis (Derville), Earlandia spp., and the problematic Asphaltinoides macadami (Brenckle and Groves) and Salebra irregularis Bogush and Brenckle. Microfossils are present in both calcareous mudstone and limestone.

The generic name Terebellina was proposed by E. O. Ulrich for large (> 100 mm long, several millimeters wide), siliceous, tubular fossils from Cretaceous rocks of southern Alaska. Originally interpreted as annelid tubes, these unusual agglutinated fossils are locally abundant in Triassic to Neogene flysch and other basinal deposits of the Pacific borderlands. Other generic names employed for the same fossils include Torlessia (used in New Zealand) and Yokoia (in Japan). Although most authors have regarded the tubes as body fossils of worms, some workers have speculated recently that Pacific Terebellina are really large bathysiphonid foraminiferids. At the same time, the name has been co-opted by trace fossil workers for thick-walled, grain-lined burrows usually occurring in outer-shelf to slope facies.

Based on comparisons with modern and fossil bathysiphonids, including a new species (Bathysiphon harperi) from the Cretaceous of southwestern Oregon, the body fossils called Terebellina are here reinterpreted as large species of Bathysiphon, and the name Terebellina is therefore a junior synonym of this foraminiferid genus. Except for the compression and recrystallization of tubes, Pacific Terebellina resemble very closely the tests of larger species of modern Bathysiphon. Terebellina should not be salvaged for use as an ichnogenus. Most of the trace fossils identified with this name in the recent literature could be accommodated in other established ichnogenera, primarily Palaeophycus (where grain-lined burrows occur individually and are dominantly horizontal) and Schaubcylindrichnus (where they occur in curved bundles).

Thirty-two new species of unilocular benthic foraminifera were described from 50 Late Oligocene to Pleistocene samples from DSDP Site 357 (Leg 39) on the Rio Grande Rise in the southwest Atlantic Ocean. These new species make up nearly one-third of the 112 species of unilocular foraminifers identified in the core. Such a high proportion of new taxa is not unexpected as the group has been ignored by most researchers.

New taxa described include Lagena praemeridionalis, Lagena rotundocostatina, Exsculptina sicula, Exsculptina umbelliforma Patterson and Cavazza, Favulina prolatella, Favulina quasiperthensis, Galwayella copiosotubula, Galwayella oscula, Galwayella spherula, Homalohedra anastomocostata, Homalohedra goniachrados, Homalohedra gothicofenestella, Homalohedra polykamptarion, Lagnea congestacolla, Lagnea derbiosa, Oolina curvella, Vasicostella lecythella, Vasicostella spinulafunda, Fissurina anapetebasilaris, Fissurina binaroculella, Fissurina favobasella, Fissurina fissuroscula, Fissurina labeona, Lagenosolenia angula, Lagenosolenia penna, Palliolatella anfracta, Palliolatella hadrocheilos, Pseudoolina becella, Pseudoolina oscillum, Parafissurina kladerorhektis, Parafissurina prolatolonga, and Pseudofissurina plastica.

The new name, Lagenosolenia incompta, is proposed for Lagena bicarinata (Terquem) var. polita Matthes, 1939.

Permian Orthotetoidea on Hydra belong to the genera Cyndalia Grant (1993a), Goniarina Cooper and Grant (1969), Derbyia Waagen (1884), Diplanus Stehli (1954), Schuchertella Girty (1904), Sicelia Merla (1934), and Tropidelasma Cooper and Grant (1969). Hydra has the most complete Permian section in the Western Tethys, 500 m thick and ranging in age from Asselian to Dorashamian. These are the youngest silicified Permian brachiopods west of China.

Four species of megathyrid brachiopods from the Lower Cretaceous (Berriasian) of Crimea, Ukraine, and one species of megathyrid from the lower Upper Cretaceous (Cenomanian) of England are reinvestigated using scanning electron microscopy. The species are variously assigned to one existing genus, Praeargyrotheca Smirnova (P. hexaplicata (Smirnova) and P. megatrema (J. de C. Sowerby)) and two new genera, Krimargyrotheca (K. concinna (Smirnova) and K. balkii n. gen. and n. sp.) and Evargyrotheca (E. alta (Smirnova)). Taxa are distinguished principally on differences in shell shape, plication, and, in particular, surface microornament. The shell microstructure of all five species is investigated with particular emphasis on endopunctation and microornament. Dental plates are present briefly early in ontogeny. Based on the possession of transient dental plates, a septalium, and conspicuous microornament, Praeargyrotheca is removed from the family Megathyrididae and assigned, along with the two new genera, to a new family Praeargyrothecidae. Scanning electron microscopy study of loop development in both fossil and Recent terebratelloids and megathyrids supports a recent immunological study of living taxa from both groups that suggests that the two groups are not as closely linked phylogenetically as previously maintained. The family Megathyrididae is thus removed from the superfamily Terebratelloidea and assigned, along with the new family Praeargyrothecidae, to a new superfamily Megathyridoidea.

The morphology of Argyrotheca lorioli Smirnova, 1972, from the Lower Cretaceous (Berriasian) of Crimea, Ukraine, was reinvestigated using SEM, found to be impunctate, and reassigned as the type species of a new genus Apodosia, new family Apodosiidae, order ?Rhynchonellida. Another micromorphic brachiopod, Spiriferina? oolitica (Moore, 1855) from the Middle Jurassic (Bajocian) Inferior Oolite of Somerset, England, is also reassigned to the new genus.

The new subfamily Struthiopterinae is proposed for the aporrhaid gastropods occurring in the Late Cretaceous-early Tertiary Weddellian Province along the southern margin of the Pacific. The following genera are placed within the Struthiopterinae: Struthioptera Finlay and Marwick, 1937; Austroaporrhais n. gen.; and Struthiochenopus n. gen. The temporal and biogeographic distribution of members of Struthiopterinae show a similar pattern to other Southern Hemisphere groups of Late Cretaceous and early Cenozoic molluscs with initial disappearance from the western Australasia of the Weddellian Province by the Paleocene while surviving in Antarctica until the late Eocene and eventually disappearing in southern South America during the early Miocene.

Also included in this paper is a reappraisal of the species assignable to these genera from Late Cretaceous and early Tertiary of New Zealand, Antarctica, and southern South America together with the description of five new species. The following new species of the Struthiopterinae are described: Austroaporrhais larseni n. sp., A. stilwelli n. sp., A. dorotensis n. sp., Struthiochenopus antarcticus n. sp., and S. philippii n. sp.

A well-preserved mouth apparatus consisting of jaws and a radula was found in situ within the body chamber of the goniatite Cravenoceras fayettevillae Gordon, 1965 (Neoglyphiocerataceae: Cravenoceratidae), from the middle Chesterian (Upper Mississippian) of Arkansas. Both upper and lower jaws consist of a black material. The lower jaw is characterized by a widely opened larger outer lamella and a shorter inner lamella. The upper jaw is fragmental. The radula is preserved in the anterior portion of the buccal space and comprises a series of tooth elements. Each transverse tooth row consists of seven teeth (a rhachidian and pairs of two lateral and one marginal teeth), with a pair of marginal plates. This arrangement is typical of radulae of other ammonoids of Carboniferous to Cretaceous age, coleoids, and the orthoconic “nautiloid” Michelinoceras (Silurian, Michelinocerida), suggesting a phylogenetic affinity among them.

Walcott described the If fauna from Silver Peak Range, Nevada in 1910 as consisting of Nevadia weeksi n. sp. and gen. and Holmia rowei n. sp. (herein recognized as Esmeraldina rowei). Being the oldest trilobite fauna known at the time, it played an important roll in Walcott's locating the base of his Lower Cambrian Waucoban Series. The original If collection is reviewed, as is more material collected near the type locality, “Nevadella” Zone, Montenegro Member of the Campeto Formation. Additional trilobite taxa herein recognized in the If collection are Esmeraldina? cometes n. sp., Esmeraldina lidensis n. sp., Palmettaspis consorta n. gen. and sp., and Palmettaspis parallela n. sp. A close similarity between E. rowei and the type species for Holmia in Baltica led Walcott to a controversial Laurentia–Baltica correlation. His incorporation of three trilobite taxa among his syntypes for Holmia rowei also posed a problem. Overriding these faults was Walcott's foresight in using the 1f fauna in his Waucoban concept. Even today, after the 1992 international agreement to lower the base of the Cambrian to a pre-trilobite horizon, the Waucoban is being applied in Canada to upper Lower Cambrian strata.

The first Silurian trilobites to be described from Alaska are of late Llandovery (Telychian) age. They occur with original cuticle intact in a white biosparite. Seven species have been identified, including Paracybantyx occidentalis n. sp., Ligiscus smithi n. sp., Calymene s.l. aff. C. iladon Lane and Siveter, 1991, Scotoharpes aff. S. raaschi Norford, 1973, Scharyia sp., a cheirurine belonging to either Radiurus Ramsköld, 1983, or Protocerauroides Chatterton and Perry, 1984, and an undetermined warburgelline. The fauna has close affinity to those described from similar lithologies in the Telychian of North Greenland. Machaeridians occurring with the trilobites include Turrilepas sp., Compacoleus sp., and Lepidocoleus cf. L. britannicus Withers, 1926.

Species of two new genera of Encrinuridae occur in the Ludlow Douro Formation at Goodsir Creek, Cornwallis Island, Gamier Bay, Somerset Island, and Prince Alfred Bay, Devon Island. The encrinurine Aegrotocatellus n. gen. includes four highly autapomorphic species, and is most closely related to Balizoma Holloway, 1980. Separate taxa are recognized at low and high stratigraphic intervals at Goodsir Creek (the type species, Aegrotocatellus jaggeri n. gen. and sp., and Aegrotocatellus n. sp. A, respectively), at Gamier Bay (Aegrotocatellus n. sp. B), and at Prince Alfred Bay (Aegrotocatellus nankerphelgeorum n. gen. and sp.). Perirehaedulus n. gen. is a coronocephaline most closely related to the Chinese upper Llandovery taxon Kailia Chang, 1974. The type species, Perirehaedulus caprus (Thomas in Thomas and Narbonne, 1979) from Goodsir Creek, is distinct from P. richardsi n. gen. and sp. at Garnier Bay. The upper Wenlock–Ludlow range of Balizoma is extended into the Arctic by Balizoma aff. B. variolaris (Brongniart, 1822) from Homerian rocks of the Cape Phillips Formation near Abbott River, Cornwallis Island, and by Balizoma sp., from the late Ludlow Douro Formation at Goodsir Creek.

Ostracodes are described from the “Cerro del Fuerte Section” and neighboring localities, all in the Precordillera de San Juan (northern Argentina, San Juan Province), and from sparse faunas in Bolivia (Chuquisaca, Tarabuco Province). Additional material comes from the collection of Thomas (1905). This preliminary study gives the first detailed description of ostracode assemblages in the Upper Silurian and Lower Devonian of the South American continent. Records of other abundant lower Paleozoic (Lower Ordovician to Lower Devonian) ostracodes in Argentina, Bolivia, Brazil, Peru, and Venezuela are also reviewed. Twelve different species, belonging to Palaeocopa (Beyrichiacea and Primitiopsacea) and to Binodicopa and Podocopa (Healdiacea, Thlip-suracea, Cypridacea) are described and a new genus is established (Australobollia n. gen.). Ostracode distribution at Cerro del Fuerte attests to the presence of the Siluro-Devonian boundary within the upper Los Espejos Formation and confirms recent stratigraphical attributions mainly based on conodonts and brachiopods (Benedetto et al., 1992). The beyrichiacean Hemsiella indicates a late Ludlow to Pridolian age for the lower part of upper Los Espejos Formation. The non-palaeocope “Thlipsurella-Phanasymmetria-Ranapeltis” assemblage found in the uppermost part of the formation indicates an Early Devonian (Lochkovian) age. The present study reveals the existence of faunal links at genus (Silurian) and probably species (Early Devonian) level between South America (Argentina, Bolivia), Laurentia, Avalonia-Baltica, and northern Gondwana. For example, close affinities (e.g., Ranapeltis sp. aff. rowlandi and Thlipsurella sp. aff. ellipsoclefta) exist between the uppermost Los Espejos Formation (Argentina) and contemporaneous horizons in the North American Mid-Continent (e.g., Haragan Formation, Oklahoma; Shriver Formation, Pennsylvania). Two types of ostracode assemblages, “beyrichiacean-dominated” and “thlipsuracean-bairdiacean-cypridacean dominated,” are recognized in the Late Silurian–Early Devonian of Argentina and discussed relative to other assemblages known in Laurentia, Avalonia-Baltica, and northern Gondwana. Their paleoecological significance in relation to marine bathymetry is addressed.

When first described, Plethoschisma grandis was thought to have an unusual plating arrangement compared to other pleurocystitids, although the ventral surface was largely unknown. New specimens showing more of the ventral surface indicate that Plethoschisma has very similar ventral plating to Deltacystis and that four of the original dorsal plate designations of Plethoschisma were incorrect. A new subfamily, Deltacystinae, is erected to receive the two similarly plated genera. The pectinirhombs of Plethoschisma are reinterpreted as confluent and in the B2/IL2 and IL3/L4 positions, and one of the new specimens has the largest pectinirhomb and greatest number of dichopores of any known glyptocystitid. A phylogenetic analysis of the Pleurocystitidae reveals that the Deltacystinae, new subfamily, is the sister group to the Pleurocystitinae, new subfamily, and that pectinirhombs apparently evolved independently in the Pleurocystitidae and the Cheirocrinidae.

Posterolateral markings, appearing as short, rectilinear grooves projecting from the posterior margins of digit IV, occur on tracks in five of 34 trackways at the Cameron Dinosaur Tracksite in the Dinosaur Canyon Member of the Lower Jurassic Moenave Formation, northeastern Arizona. A new ichnospecies, Grallator (Anchisauripus) madseni, is described from these five trackways made by bipedal, tridactyl dinosaurs. The size and morphology of the tracks suggest that they may represent trackmakers similar to Coelophysis and Syntarsus, two dinosaurs described from Triassic and Jurassic deposits in northeastern Arizona and northwestern New Mexico.

Among the working hypotheses cited as possible causes of the posterolateral markings are: 1) they were made by the dragging of digit III or of the metatarsus; 2) they are marks produced by a feature similar to a horny excrescence or cornified ridge on digitometatarsal pad IV; and 3) they are related to a peculiarity that may have resulted from sexual dimorphism.

Preservation of relict color patterns on fossil nautiloid cephalopods is a relatively rare phenomenon. Reports of this phenomenon as summarized by Kobluck and Mapes (1989, table 2) for the Paleozoic indicate that perhaps as many as 32 genera with coiled, orthoconic, and cyrtoconic conchs have been described with relict color patterns. However, reports of Mesozoic occurrences are limited to only Ophionautilus? in the Jurassic (Shimanski, 1962) and Eutrephoceras in the Cretaceous (Shimanski, 1962; Landman, 1982). Cenozoic reports are limited to Aturia in the Tertiary (Foerste, 1930; Shimanski, 1962; Teichert, 1964) and modern Nautilus (see Saunders and Landman, 1987, for an extensive treatment). The reports on both Mesozoic occurrences are limited to description of external conch morphology, detailed appearance of the color patterns, and the relationship of the remnant color pattern to the conch morphology. Indeed, the specimen discussed herein was originally illustrated by Landman (1982, fig. 8), with a caption indicating the presence of possible color banding. Analysis of this Cretaceous specimen allows comparison to Nautilus and provides a suggestion as to the evolution of certain mature color patterns in coiled cephalopods from the late Mesozoic to Recent.

Colonial rugose corals are uncommon in Pennsylvanian rocks in North America and until now the only massive form known from rocks of this age south of the Arctic is an undescribed species of Petalaxis reported by Sutherland (1985) from Morrowan rocks in Oklahoma, Texas, and New Mexico. This report concerns a second species of Petalaxis recovered from Desmoinesian rocks immediately west of Death Valley, California. Although only a single colony has been found, it is profoundly different from all other described species of this genus and is significant from the standpoint of its presence during a very long time span when there was an apparent dearth of massive rugose corals in most of North America.

Formic acid must be buffered with both calcium carbonate and calcium phosphate to be suitable for extraction of conodont elements and other phosphatic fossils from dolomites. All unbuffered solutions and those buffered with only calcium carbonate or calcium phosphate destroy the phosphatic fossils. Experimental effects using different concentrations and different combinations of phosphate and calcium carbonate are diagrammatically illustrated. A 10 percent formic acid solution with 20 g calcium carbonate and 1.2 g tricalcium phosphate per liter leaves conodont elements undamaged even for a period of 129 days. One liter of this solution dissolves 95 g dolomite.