Recently collected specimens allow a better characterization of the frond architecture of Sphenopteris pottsvillea (White) Gastaldo and Boersma from the Plateau and Warrior Coalfields, Alabama. The bipartite frond consists of a naked petiole of moderate length (>0.3 m) and two pinnule-bearing sections. The angle of rachial bifurcation varies from 35° to 65°, with no one angle of divergence dominating the sample population. Basal exterior lateral rachises develop first, are oblong in outline, and do not possess spine-like prolongations. Lateral rachises develop alternately along each pinnule-bearing section. Pinnule-bearing sections of the described leaf fragment exceed 0.5 m in length, and the dimensions of an entire frond probably approached 2.0 m.

A Campanian fish assemblage is described from the uppermost Blufftown Formation in western Georgia. Fifteen chondrichthyan and eight osteichthyan taxa are identified, virtually all for the first time from the region. The study area represented a transitional zone between the Atlantic and eastern Gulf of Mexico Coastal Plain Provinces during the Late Cretaceous, and shows faunal relationships with both.

Paramys compressidens Peterson, from the Uintan of Utah, has long been considered a member of the genus Ischyrotomus Matthew. A re-examination of the type and referred specimens of this species demonstrates that it does indeed belong in the genus Paramys and that several of the previously cited referred specimens can be allocated to other known species.

Systematic relationships between the species of Paramys are analyzed. Recognizable morphoclines within this genus are increase in size and amount of crenulation of the enamel on the cheek teeth, and changes in the cross-sectional shape of the lower incisor. Several species previously considered as belonging to Paramys (P. simpsoni Korth, P. savagei Michaux, P. pourcyensis Michaux, P. ageiensis Michaux) may be referable elsewhere.

Thisbemys Wood, Leptotomus Matthew, and Tapomys Wilson can be directly derived from the known species of Paramys. The origin of several other genera may possibly be found within Paramys, but no ancestral morphotype is currently known.

Recently Ellis L. Yochelson visited the Shanghai Museum of Natural History and saw the illustrated specimen of Dentalium (A.) acumen from the lower Carboniferous of Guizhou Province, China. He pointed out that the straight shell of Dentalium (Antalis) acumen (Koninck) which was described by Wang (1987) is an orthoconic cephalopod. The anterior part of the shell is crushed, as is common on the living chamber of those orthocones which preserve it. Examination of the early part of the shell showed that it was broken along a curved surface; that is, it broke along a septal wall. By wetting this area, it was possible to see the outline of a central siphuncle at this septum. Thus, it remains true that until now, no scaphopod has been recorded in Chinese Paleozoic beds.

A prominent anterior bulge on a ceratopsian dinosaur phalanx was examined for evidence of infection or stress (fatigue) fracture. The presence of a knife-slice type radiolucency, associated with periosteal reaction, was pathognomonic (diagnostic) for a stress fracture. Stress fractures have previously been recognized only in humans, racing greyhounds, and horses.

With the quest for more detailed and precise micropaleontologic data has come a stronger emphasis for quantitative studies of microfossils. Many workers have realized, however, that slide preparation and counting can contribute large errors in quantitative studies (Battarbee, 1973; Moore, 1973; Hattner and Wise, 1980; Laws, 1983).

Middle and lower Ordovician gastropods have not previously been described from Alaska, and the genus Helicotoma Salter has not been reported from western and arctic North America with the exception of one locality in California (Rohr, 1980). Like many other Paleozoic gastropod genera, Helicotoma has several species assigned to it, but the species are often based on poor material and, in some cases, on a single specimen. This lack of knowledge of variation within the species as well as the detailed features of the shell make further interpretations of the gastropods difficult. The occurrence of relatively abundant, well-preserved Helicotoma specimens in Alaska is important for biogeographic and biostratigraphic studies of lower Paleozoic mollusks.

Although the burrows and trails in the Upper Ordovician rocks around Cincinnati, Ohio, have been fully documented and are well known (Osgood, 1970), comparatively little attention has been paid to the borers. Nevertheless, borers are very common in a variety of hard substrates in these rocks. These substrates include the skeletons of bryozoans, corals, and stromatoporoids (Palmer and Wilson, 1988), as well as cobbles and hardgrounds (Palmer, 1982; Wilson, 1985). By far the most common type of boring is the elongate tube Trypanites, which could have been made by a variety of filter-feeding worms. Trypanites is common on hard substrates throughout the lower Paleozoic (Palmer, 1982).

Recent advances in microcomputer technology have created many tools for image processing and analysis that are useful for paleontologic studies. Although the Journal of Paleontology is not the appropriate forum for reviews of products from the rapidly changing field of computer technologies, a brief introduction to techniques presently available for image processing and analysis, and their potential applications to the field, may be of value to paleontologists.

The pseudorthoceratid subfamily Macroloxoceratinae Flower, 1957, comprises a rare group of nautiloid cephalopods homeomorphic with the Actinoceratida in the development of a siphonal canal system. With the exception of Macroloxoceras Flower, 1957, from the Upper Devonian of Colorado and New Mexico, this subfamily has previously been reported only from the Mississippian of Europe. A specimen described herein from the late Viséan–?early Namurian Kennetcook Limestone of the Windsor Group of Nova Scotia, assigned to Campyloceras cf. C. unguis (Phillips, 1836), extends the range of the Macroloxoceratinae into the North American Mississippian. This discovery further provides new data on the complex siphonal morphology of this poorly known group of nautiloids, and supplements the recent documentation of the pseudorthoceratids in the Windsor Group cephalopod fauna (Edgecombe, 1987).

A large-diameter coring device was designed to recover plant litter in fluvial sediments as part of a taphonomic study of plant deposition in a modern river system. The corer was used to retrieve unconsolidated sediments from shallow (< 1.5 m) water, either from a boat or from the riverbank, and was designed to be transportable for use in remote reaches of tropical rivers. The device is operable by a single person, easily repaired, and rugged.

The trilobite Phacops rana has previously been documented in two life positions: horizontally outstretched and enrolled (Hall and Clarke, 1888). A specimen of Phacops rana was recovered in an unusual life position from the Windom Member of the Moscow Formation (Figure 1). It was collected from a borrow pit along Castle Hill Road, 1 km east of Earlville in Chenango County, New York. The trilobite appears to have burrowed tail first into the substrate, with only part of the cephalon and one or two thoracic segments exposed above the sediment surface. The orientation of the eyes indicate that the visual field was horizontal. The thorax angled into the substrate at an angle of approximately 50° from the horizontal, with the pygidium tilted dorsally relative to the thorax. Compaction effects appear to be slight. Because the specimen was found in situ, no doubt exists as to its orientation with respect to bedding. It is also evident from bedding plane surfaces that this trilobite had burrowed, and was not simply draped over an uneven substrate, as it intersects three bedding planes. There is no evidence of any object over which it could have been draped. No burrow trace, lining, or scratch marks are preserved. No other specimens of Phacops in this position have been reported.

H. C. Lea (1843, 1846), in papers on molluscs from the Tertiary of Virginia, described and illustrated the scutum and carina of a scalpellid barnacle, which he mistakenly identified as two new species of molluscs. The scutum was described as Avicula multangulata (after 1843 as A. multangula) and the carina as Patella acinaces. Conrad (1863), Meek (1864), d'Orbigny (1852), and Heilprin (1884) listed these species in their enumerations of the Tertiary molluscan fauna. Meyer (1888, p. 138) was the first to recognize the cirriped nature of these fossils. He correctly identified the plates as scutum and carina, assigned them to Scalpellum magnum Darwin, 1851, an English Pliocene species, and provided detailed figures of the type specimens from the collection of the Academy of Natural Sciences of Philadelphia (Meyer, 1888, figs. 11, 12a).

In a recent paper, Kobluk and Lysenko (1987) described the effects of hurricanes on coral and milleporid distribution in coral reef rubble near the coast of a Fijian island. Their main thesis was that cryptic sub-rubble coral populations may act as “preserves” for reef surface communities. This was supported by data showing that on the protected undersides of boulders the composition of post-hurricane coral and milleporid populations were little changed from their pre-hurricane states. In a final section entitled “Paleontological implications,” Kobluk and Lysenko (1987, p. 673) stated, “Wilson (1985) studied just such a rubble-dwelling fauna in the Ordovician of Kentucky.” The authors then discussed “another interpretation” of the paleoecologic succession described in Wilson (1985). Because the Ordovician succession described by Wilson may be one of the few valid examples of an autogenic ecological succession in the fossil record (see Miller, 1986) the re-interpretation by Kobluk and Lysenko (1987) must be answered.

The genus Rhectomyax was proposed by Stewart (1930) for Asaphis undulatus Gabb, 1864, a small bivalve described from fossils collected in a mine shaft sunk between BeaPs Bar and the Half Way House, not far from Texas Flat and near the Placer-Sacramento County line, California. The age of this mine shaft collection remains imprecise, but it is Late Cretaceous and probably from within the Campanian. Although Stewart's description of Rhectomyax follows his discussion of Asaphis Modeer, 1793 (Stewart, 1930, p. 285), and is not set off from other genera included by him in the “Garidae,” he ended his description with, 4T have been unable to recognize the affinities of this shell.” Rhectomyax is the oldest genus included by Keen (1969, p. N633) in the family Psammobiidae.