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Relevant physiological differences are discussed to determine their potential influence on the change in dominance within marine level-bottom communities from articulate brachiopods in the Palaeozoic to filter-feeding bivalves in the Mesozoic and Cenozoic.

• Read more about The physiological differences between articulate brachiopods and filter-feeding bivalves as a factor in the evolution of marine level-bottom communities

The geology, palaeoecology, and vertebrate fauna of a mammaliferous sediment in the Forest Marble of Oxfordshire are described, as are the techniques used in its processing. The mammalian fossils appear to have been derived from the faeces of predatory animals, probably small theropods, the occurrence of theropod teeth possibly having value in the search for new Mesozoic mammal localities. In the mammal (s.l.) fauna from the new site there occur late representatives of the Morganucodontidae (Wareolestes rex gen. et sp. nov.), Kuehneotheriidae (Cyrtla-therium canei gen. et sp.

• Read more about A Middle Jurassic mammal bed from Oxfordshire

Five trilobite species from the Coniston Limestone Group of the southern Lake District are redescribed, on the basis of type and topotype material, and one new genus, four new species, and one new subspecies erected. A lectotype of Sphaerexochus? boops Salter is designated and topotype material described; the species is placed in Pseudosphaerexochus. Encrinurus kingi Dean is redescribed and placed in Erratencrinurus, for which a type species is designated; this represents the first record of this genus in Britain.

• Read more about Trilobites from the Coniston Limestone Group (Ashgill Series) of the Lake District, England

New acrotretacean brachiopods are described; Caenotreta aldridgei gen. et sp. nov. from the Llandovery of the Welsh Borderland, England, C. celloni sp. nov. from the Llandovery of the Carnic Alps, Austria and Caenotreta sp. from the late Silurian of the Carnic Alps. There are also new records from the Devonian of Germany. The possible ecology of these micromorphic conical forms is discussed.

• Read more about New acrotretacean brachiopods from the Palaeozoic of Britain and Austria

This extensive compression flora from the late Silurian (Downtonian) of South Wales contributes to our understanding of terrestrial vegetation relatively early in the colonization of the land by predominantly vascular plants. The large number of fertile Cooksonia specimens has resulted in an amplified diagnosis of C. hemisphaerica Lang for which mtraspecific variation is demonstrated; in the erection of a new species, C. cambrensis, and in records of plants close to C. caledonica and C. pertonii. Elongate sporangia on unbranched twisted stalks are named Tortili-caulis transwalliensis gen.

• Read more about A late Silurian flora from the Lower Old Red Sandstone of south-west Dyfed

Palaeocene and Eocene crabs are described from the Sulaiman and Kirthar Ranges of east Pakistan. Ten species are represented, eight of them new, belonging to nine genera, two of them new. The new genera and species are Hepatiscus sheranii sp. nov., Laeviranina sinuosa sp. nov., Pyromaia inflata sp. nov., Gillcarcinus amphora gen. et sp. nov., Proxicarpilius planifrons gen. et sp. nov., Proxicarpilius minor gen. et sp. nov., Hexapuspinfoldi sp. nov., and Lobonotus orientalis sp. nov.

• Read more about New Lower Tertiary crabs from Pakistan

The compound eyes of trilobites are the oldest of all known visual systems and their evolution can be traced over 350 million years. Only the lentiferous surface is preserved, however, since the lenses alone are calcitic.Holochroal eyes have many lenses closely packed together.

• Read more about The visual system of trilobites [Twenty-first Annual Address, delivered 8 March 1978]

In the Late Cretaceous, diversity of gymnospermous orders increased due to the appearance of true Cycadales. Most groups experienced important evolutionary changes. Extant genera first appeared among Cycadales (Cycas), Ginkgoales, and Coniferales. Noteworthy evolutionary innovations were phylloclades in the Cupressaceae and distinctive stomatal types in the Araucariaceae. Sequoia and Parataxodium achieved dominant status. At the Cretaceous Tertiary boundary, the Caytoniales, Bennettitales, and Nilssoniales died out.

• Read more about Late Cretaceous gymnosperms from Sakhalin and the terminal Cretaceous event

Conodont faunas from the Plymouth Limestone are indicative of levels ranging from the Middle Devonian patulus Zone to the Upper Devonian crepida Zone. The conodont faunas are described and compared with European counterparts, with which correlations are proposed. Although there are anomalies in some distributions, the conodonts have provided a tool for the dating and correlation of disjunct sections of Plymouth Limestone, and have enabled the elucidation of stratigraphical, palaeoenvironmental and structural aspects of the carbonates.

• Read more about The conodont biostratigraphy of the Devonian Plymouth Limestone, South Devon

The chondrostean redfieldiiform fish Helichthys, from the Triassic of Bekker's Kraal, South Africa, is redescribed. The genus is monospecific and five species are synonymized with the type-species H. browni. The possible phylogenetic position of the genus within the Redfieldiiformes is discussed.

• Read more about The anatomy and phylogenetic position of Helichthys, a redfieldiiform fish from the Triassic of South Africa