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The brachiopod fauna of the upper part of the rocks of Ashgill age in the Oslo-Asker area, Norway, is reviewed prior to an assessment of the ecology of the macrofauna found in this Rawtheyan and Hirnantian regressive sequence, a regression caused by the contemporary glacio-eustatic lowering of sea level. Most of the elements of the cosmopolitan Hirnantia Fauna occur, some very commonly, such as Dalmanella, Hirnantia, Eostropheodonta, Cliftonia, and Hindella, but other elements are rare or absent; many additional genera are also noted.

• Read more about The commoner brachiopods of the latest Ordovician of the Oslo-Asker district, Norway

The skull of a new fossil reptile, Planocephalosaurus robinsonae gen. et sp. nov., is described and its affinities discussed. The description is based on approximately 750 isolated skull bones recovered from Triassic fissure infills in Carboniferous Limestone in the Bristol Channel area. The skull is diapsid, although there is usually a small gap present in the lower temporal bar. Further evidence that an incomplete lower temporal bar is not a uniquely squamate character is provided.

• Read more about A new rhynchocephalian from the British Upper Trias

Bivalves of the genera Praebuchia and Buchia described here occur in great abundance in the Oxfordian to Valanginian Stages of East Greenland. Fifteen species have been identified. Their stratigraphic range is roughly the same as in other Arctic areas, and a detailed zonation based on buchiid bivalves seems to be valid from Arctic Canada over East Greenland to Andoy, Svalbard, Petshora River basin, Subarctic Urals, and northern Siberia.

• Read more about Buchiid bivalves from the Upper Jurassic and Lower Cretaceous of East Greenland

Fossil forests and forest floors have been found in the Lower Cretaceous part of the Fossil Bluff Formation in south-east Alexander Island, Antarctica. These grew at an apparent palaeolatitude of 65° to 75° S., within the Cretaceous polar circle. Analyses of the well-preserved growth patterns have yielded important information about periodicity of growth, and the effect of rapid burial on trees. Increments of annual growth were very variable and growth rates were high. These growth characteristics are very different from those of modern high-latitude trees.

• Read more about Fossil forests from the Lower Cretaceous of Alexander Island, Antarctica

Specimens of Aratrisporites, a miospore genus of probable lycopsid affinity, are common in some palynofloral assemblages of Early Triassic age, from the Rewan Formation of the Bowen Basin, Queensland. Study of numerous specimens from a sequence about 1710 m. thick supports the view that A. tenuispinosus developed, by increase in spine dimensions, from A. wollariemis. The observed development of this evolutionary sequence favours quantum speciation, rather than a gradualistic process, as the change from one species to the other takes place over a relatively short stratigraphic interval.

• Read more about An evolutionary sequence in Aratrisporites miospores from the Triassic of Queensland, Australia

The large Asiatic anchitheriine, Sinohippus zitteli, is discussed and compared with some other Old and New World anchitheriines.

• Read more about The taxonomic status of the Miocene horse genus Sinohippus

Eoharpid trilobites from the Ordovician of Brittany and Portugal are revised. Eoharpes guichenensis Henry and Philippot of Llandeilo age from Brittany is redescribed on the basis of new material and E. macaoensis sp. nov. of probable Caradoc age from central Portugal is described. The broadly contemporaneous Armorican species E. guichenensis and E. cristatus Romano from north Portugal enforces the strong faunal link between the Martigne-Ferchaud synclinorium south of Rennes and the Valongo area during the Llandeilo.

• Read more about The trilobite genus Eoharpes from the Ordovician of Brittany and Portugal

The small temnospondyl amphibians from the Middle Pennsylvanian Francis Creek Shale of Mazon Creek near Morris, Illinois, are redescribed together with recently collected Francis Creek Shale specimens from Pit 11 near Braidwood, Illinois. A well-preserved larval specimen of the trimerorhachoid Saurerpeton cf. obtusum represents a new record for the 'Mazon Creek' fauna. It demonstrates the presence of three pairs of external gills and rows of ceratobranchial dental ossicles modified as gill rakers in a larval saurerpetontid. Amphibamus grandiceps Cope from Mazon Creek and the contemporary A.

• Read more about Small temnospondyl amphibians from the Middle Pennsylvanian of Illinois

The type specimen of Reimannia aldenense, from the Middle Devonian of New York, was reinvestigated in order to more critically evaluate the anatomy of this poorly understood monotypic genus. Three successive axis orders were observed in organic connection. The first-order axis contains a three-ribbed primary xylem column showing mesarch order of maturation with protoxylem strands along median-radial planes and near the tips of primary xylem ribs. Traces appear to be produced in a helical arrangement.

• Read more about The Devonian plant Reimannia, with a discussion of the class Progymnospermopsida

Bioclastic sands of the Coralline Crag are characterized by abundant bryozoans including large colonies of four cyclostomes: Blumenbachium globosum Koenig, Meandropora aurantium (Milne Edwards in Lyell), M. tubipora (Busk), and Multifascigera debenensis sp. nov. These species are systematically described and the relationships investigated between colony growth pattern, form, and inferred ecology. Colonies of each species are composed of numerous subcolonies bounded by exterior walls. Times of autonomous subcolony growth were punctuated by periods of subcolony anastomosis.

• Read more about Palaeobiology and systematics of large cyclostome bryozoans from the Pliocene Coralline Crag of Suffolk