Stromatoporoids are found in all five members of the Manlius Formation of New York and are abundant at many localities. The fauna is dominated by two closely related species, Habrostroma microporum (Girty) and H. centrotum (Girty). Present in lesser numbers are Intexodictyon manliusense n. sp., Plectostroma micum (Bogoyavlenskaya), Actinostromella vaiverensis Nestor, Densastroma pexisum (Yavorsky), Habrostroma cf. H. centrotum (Girty), and ?Parallelostroma sp. The assemblage displays both Silurian and Devonian affinities.

Stratigraphic distribution of two key brachiopod species in the Ramp Creek Formation and Harrodsburg Limestone (middle Mississippian) in south-central Indiana suggests the boundary between the Osagean and Meramecian Series lies in the lower part of the Ramp Creek Formation. Marginirugus magnus (Meek and Worthen), an Osagean index fossil, ranges into the lower part of the Ramp Creek Formation. Warsawia lateralis (Hall), a Meramecian index fossil, also occurs in the lower part of the Ramp Creek Formation and in the lower part of the Harrodsburg Limestone. Thus, the upper part of the Edwardsville Formation and lower part of the Ramp Creek Formation in Indiana are temporally equivalent to the lower half of the Warsaw Formation in the Mississippi Valley. The upper part of the Ramp Creek Formation and the lower part of the Harrodsburg Limestone are temporally equivalent to the upper half of the Warsaw Formation.

A new lamellorthoceratid genus, Plicatoceras, is defined on the basis of Plicatoceras nishidai n. sp. from the early Gedinnian shale of the Fukuji Formation in central Japan. The new genus is the earliest known member of the Lamellorthoceratidae and is the first record of a lamellorthoceratid cephalopod from East Asia.

Cryptolithinid trilobites have been repeatedly described from North America for over 150 years. Earlier work on these forms is here integrated with new information from Oklahoma to form a strong case for the following conclusions: 1) the genus Cryptolithus migrated to (present-day) eastern North America from Europe at a single time in the early Caradoc; 2) it gave rise rapidly to a western North American relative, Cryptolithoides; 3) both genera were restricted to relatively cool-water shelf environments roughly 30 m deep and remained, in general, geographically isolated for several million years. The Viola Group, geographically between these eastern and western occurrences and representing much of Middle and Upper Ordovician time, chronicles the interplay between these two genera over some six million years.

In the biogeographic boundary region formed by Oklahoma, the two supposedly distinct genera showed suprising convergence of fringe pit and other character traits as marine transgression reduced provinciality through Ordovician time. This suprising convergence of genera is interpreted as hybridization of mere subspecies after several million years of incomplete geographic separation.

Systematic revisions and revised stratigraphic occurrences are made to Aorocrinus, Dorycrinus, Macrocrinus, Paradichocrinus, Strotocrinus, and Uperocrinus from the Osagean and Meramecian stratotype region in Iowa and Missouri. Systematic revisions include the assignment of Batocrinus procerus Miller and Gurley as a junior synonym of Macrocrinus mundulus. Batocrinus heteroclitus Miller and Gurley, B. vicinus Miller and Gurley, and B. stelliformis Miller and Gurley are assigned to Uperocrinus heteroclitus n. comb. The concept of Aorocrinus spinosulus (Hall) did not match characteristics of the holotype. Consequently, the appropriate name for this concept is Aorocrinus kelloggi (Worthen) n. comb., and A. spinosulus is assigned to Dorycrinus mississippiensis as a junior synonym. Batocrinus strenuus is assigned to Aorocrinus strenuus n. comb.?; and Strotocrinus glyptus is regarded as the valid name for the only species recognized in this genus.

These systematic revisions result in the restriction of Strotocrinus glyptus to the middle Osagean Burlington Limestone, and extension of Aorocrinus, Dorycrinus, Macrocrinus, and Uperocrinus into the Meramecian upper Warsaw Formation.

The Providence Limestone member of the Dugger Formation in Indiana and its lithologic correlatives in the southern part of the Illinois Basin are thin lime mudstones to packstones lying stratigraphically between the Herrin and Hymera Coal Members of the Dugger Formation and their equivalents. The purposes of the study are to describe and correlate the Providence conodont fauna and to apply biofacies analysis and petrographic study to interpreting the paleoenvironments.

Providence conodonts are dominated by representatives of the Idiognathodus-Streptognathodus plexus. Hindeodus is abundant; Neognathodus is common; and Idioprioniodus, Adetognathus, and Diplognathodus are common only in some sections. Aethotaxis is a minor constituent.

Conodont biofacies reflect a shallow, nearshore, low- to moderate-energy marine environment. The Idiognathodus-Streptognathodus plexus indicates quiet to moderately elevated energy levels. Hindeodus replaces part of the Idiognathodus-Streptognathodus plexus in higher energy conditions. Diplognathodus has an affinity for low to slightly elevated energy conditions. Migration during ontogeny to quite, organic-rich water from a more open, slightly higher energy environment is indicated for Streptognathodus oppletus.

Assignment to the Neognathodus dilatus-N. roundyi zone indicates a middle Desmoinesian age. The new species Diplognathodus indianaensis is morphologically intermediate between the early Desmoinesian D. coloradoensis and the late Desmoinesian D. illinoisensis and allows refinement of a Diplognathodus-based zonation.

Abundant and well-preserved tetrapod footprints have been discovered in the Glenshaw Formation (Lower Conemaugh Group) in Wayne County, West Virginia. The tracks occur along at least three horizons within a 30-cm-thick stratigraphic interval about 15 m (50 ft) above the Brush Creek Limestone; they are of Missourian age. The tracks are preserved mainly as casts on the underside of thin-bedded, ripple cross-laminated sandstones and less commonly as molds in intervening dark-gray shales. Associated body fossils include Spirorbis worm tubes and washed-in plant debris. Facies characteristics indicate the tracks were formed along the margins of an ephemeral lake in a flood basin setting adjacent to delta plain fluviodeltaic channel systems. Short-lived lacustrine conditions were likely to have resulted from a seasonal tropical to subtropical climate.

Most of the tracks can be assigned to the ichnogenus Limnopus, making them one of the earliest known occurrences. At least five trackways are discernible with an external width ranging from 320 to 400 mm. Limnopus glenshawensis, a new ichnospecies, is herein proposed and various morphologic and locomotion parameters are quantified. Mean values include stride/manus, 407 mm; stride/pes, 411 mm; oblique pace/manus, 313 mm; oblique pace/pes, 317 mm; pace angle/manus, 82.4 degrees; pace angle/pes, 80.5 degrees; glenoacetabular distance, 329 mm; manus length, 87.2 mm; manus width, 104.2 mm; pes length, 121.4 mm; pes width, 112.7 mm. The tracemaker was most likely an eryopoid amphibian with a total length of slightly over 1 m.

The atlas-axis complex in the Early Permian diadectomorph Diadectes is shown to be similar to those of a variety of primitive amniotes. Diadectes does not possess elements in addition to the standard complement seen in advanced batrachosaurs and primitive amniotes as previously thought. Characteristics of the complex include: paired, well-developed proatlases and atlantal neural arches, lack of atlantal neural spines, an extremely robust atlantal intercentrum, fusion of the atlantal pleurocentrum and axial intercentrum, a large anterior projection of the axial intercentrum, exclusion of the atlantal pleurocentrum from ventral exposure, fusion of axial neural arch and pleurocentrum, and a robustly developed axial neural spine. An analysis of the transformations of the atlas-axis complex in advanced anthracosaurs and primitive amniotes indicates that many of the characteristics of the complex previously thought to be definitive of amniotes or reptiles appear to be conditions common to Diadectes plus Amniota.

The problematical rodent genus Cedromus Wilson, previously only known from the Orellan of the Great Plains, has been considered a sciurid by some authors and an aplodontid by others. An excellent collection of complete skulls with associated mandibles from Converse County, Wyoming, has provided evidence that this genus is a sciurid but that it represents a new subfamily distinguished from all other sciurids by a unique zygomasseteric structure that closely approaches myomorphy. A second genus, Oligospermophilus Korth, also from the Orellan of the Great Plains, is allocated to this subfamily.

Additional and more complete cranial material of the primitive aplodontid Prosciurus indicates that sciurids and aplodontids share a common ancestry and should be included together at least within the same suborder Sciuromorpha.

Three species of Cedromus are recognized, C. wardi Wilson, C. wilsoni n. sp., and Cedromus sp.; the latter extends the known temporal range of the genus into the Whitneyan.

Isolated teeth and post-cranial elements of fossil vertebrates were recovered from sand and gravel pits in valley fill and terrace deposits along the Nueces River in San Patricio and Nueces Counties, Texas. A log from the valley fill deposit has been radiocarbon dated at 13,230 ± 110 BP. The fauna is mixed and comprises typical late Pleistocene taxa and relatively abundant remains of early Pliocene (latest Hemphillian) horses. The latter group includes Astrohippus albidens (Mooser), Nannippus spp., Neohipparion eurystyle (Cope), and a derived species of either Calippus or Pseudhipparion. Many of these specimens show little or no evidence of abrasion, in spite of the fact that they may have been transported at least 12–25 km. The source beds for these early Pliocene horses are unknown, but the fossils were probably eroded from older, updip sediments of the upper Goliad Formation during a low stand of sea level at the end of the Pleistocene and deposited during the late Wisconsinan.

Fossil ophiuroids (Echinodermata) have been recovered from rocks of the Comanche Series (Albian, Early Cretaceous) at Cerro de Cristo Rey, New Mexico. This is the first report of fossil ophiuroids from Mesozoic rocks in New Mexico.

Macro- and microfossils are commonly preserved as external molds as a result of decay or dissolution of soft and mineralized body parts after compaction and cementation of the surrounding matrix. The molds, which often preserve external features of the organism in great detail, are difficult to compare to other specimens. To enhance study, positive casts are typically made. Numerous compounds can serve as a casting medium (Rigby and Clark, 1965; Rixon, 1976). In microfossil studies latex rubber (Klapper in Winder, 1966; Ellison, 1987; Tull et al., 1988) and silicone rubber (G. Miller, personal commun.) are the most commonly used materials. An alternative technique is to photograph the mold directly using a scanning electron microscope (SEM).