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Analysis of growth rings in Albian and Cenomanian (late Cretaceous) coniferous wood from the North Slope of Alaska (74-85° N. palaeolatitude) has shown that tree growth was rapid and steady during the growing season, resulting in wide growth rings and few false rings, that narrow late wood, as little as one cell wide, indicates that tree growth ceased abruptly at the end of the growing season owing to rapid onset of winter darkness, and that inter-annual growth was variable.

• Read more about Middle Cretaceous wood from the Nanushuk Group, central North Slope, Alaska

The complicated shell form of heteromorph ammonoids can be considered simply as an integration of ad hoc accretional growth of the aperture, without defining any coordinate system. This 'growing tube model' is newly developed herein, using differential geometry, and is applicable to the growth pattern of any coiled shell. Using the model, any coiled shell with a circular cross-section can be analysed and described by three differential parameters: E, radius enlarging ratio; C, standardized curvature; and T, standardized torsion.

• Read more about Analysis of heteromorph ammonoids by differential geometry

It is suggested that the rhynchonellid brachiopods survived to the present day whilst all other forms with spirolophous lophophores became extinct because the latter were restrained by calcareous spiralia whereas the former were able to extend their lophophores outside their shells.

• Read more about Why the rhynchonellid brachiopods survived and the spiriferids did not: a suggestion

Early diagenesis of calcareous concretions in the Santana Formation (Cretaceous) of north-east Brazil has allowed some fishes killed in mass mortality events to be preserved three dimensionally. Fluctuating salinities may have been responsible for the mass deaths of the dominantly marine fish fauna. Early phosphatization, brought about by bacterial activity, has allowed a variety of soft tissues to be preserved within the body cavity of a variety of fish taxa.

• Read more about Preservation of fish in the Cretaceous Santana Formation of Brazil

A new osteolepiform fish, Beelarongia patrichae gen. et sp. nov., is described from the Late Devonian (Frasnian) lacustrine Mount Howitt site, eastern Victoria. Beelarongia is cosmine-covered, has a broadly flaired parietal shield with large extratemporal bones, cheek plate with an additional small postorbital bone and broad lateral extrascapulars. The orbits are very small. The scales are rhombic with high dorsal processes.

• Read more about An unusual osteolepiform fish from the Late Devonian of Victoria, Australia

The two characteristic Cathaysian Carboniferous-Permian genera Tingia and Tingiostachya are reviewed and rediagnosed in the light of new specimens from Taiyuan, northern China. Epidermal features of Tingia include bands of longitudinally arranged stomata. Tingiostachya is shown to have spirally arranged sporophylls with each bearing one spheroidal sporangium, rather than the previously described whorls of four sporophylls and tetralocular sporangia. Tingiostachya tetralocularis and Tingia elegans are rediagnosed.

• Read more about A re-evaluation of the plants Tingia and Tingiostachya from the Permian of Taiyuan, China

Based on Late Cretaceous fossils from Seymour Island, hexanchiform sharks and a beryciform teleost are reported from the Antarctic region for the first time. The hexanchiform is a species of Notidanodon, and the beryciform is a new genus and species of Trachichthyidae. Fragmentary orthacodontid teeth (Sphenodus? sp.) are also reported. An abundance and variety of indeterminate teleost bone fragments (e.g. isolated teeth and centra) were also found.

• Read more about New Cretaceous fish fossils from Seymour Island, Antarctic Peninsula

The ammonite fauna of the Santonian stage in its type area and adjacent parts of northern Aquitaine is revised, and five species recognized: Placenticeras polyopsis (Dujardin, 1837), P. paraplanum Wiedmann, 1978, Texanites (Texanites) gallicus Collignon, 1948, Eulophoceras austriacum (Summesberger, 1979) and Boehmoceras loescheri Riedel, 1931. The Santonian corresponds to the range zone of P. polyopsis, the P. syrtale of European authors, a view already expressed by A. de Grossouvre in 1901; no finer zonal division based on ammonites is recognizable.

• Read more about Ammonites from the type Santonian and adjacent parts of northern Aquitaine, western France

European Silurian myodocopid ostracodes form part of an almost exclusively pelagic, recurring faunal association. In general, they are facies related to typically laminated mud-silt or carbonate sequences deposited in relatively quiet, low energy, probably outer shelf to shelf slope environments. Their palaeogeo-graphical and facies distributions may in part be due to depth control.Reticulation, corrugation, and tuberculation are recognized as the true, genetically controlled external shell ornament in Silurian bolbozoid and 'cypridinid' myodocopids.

• Read more about Silurian myodocopid ostracodes: their depositional environments and the origin of their shell microstructures

The systematics of meniscate trace fossils are in need of revision. Most authors follow Seilacher and call unbranched, unlined meniscate burrow fills Muensteria. However, Sternberg's original description of Muensteria is highly confused, involving true algae, a coprolite, and forms of Chondrites, and the name cannot be considered available for trace fossils. Re-examination of the original description of Taenidium Heer has revealed that the earliest ichnospecies erected, T. serpentinum, corresponds closely to the forms called Muensteria in the more recent literature.

• Read more about Meniscate trace fossils and the Muensteria–Taenidium problem