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Two records of pterosaurs, the earliest from the Western Hemisphere, are reported from the Kayenta Formation (?Early Jurassic) of north-eastern Arizona. The first specimen represents a new genus and species, Rhamphinion jenkinsi.

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The Upper Carboniferous amphibians from Newsham in Northumberland constitute one of only five large, compact tetrapod assemblages known from the Westphalian of Europe and North America. The environment in which the Newsham tetrapods were preserved appears to have been a large and deep freshwater lake occupying a stretch of abandoned river channel.

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The computer-based data handling system at the Sedgwick Museum is a specialized application of the GOS program package, geared to the requirements of a large palaeontological collection. Rigorous analysis and careful structuring of palaeontological data facilitate the automatic production, by machine processing, of hard-copy catalogues, labels, and a variety of indexes. The system goes beyond the capabilities of the standard GOS package in that a number of extra programs are geared to direct access information retrieval.

• Read more about Computer-based storage and retrieval of palaeontological data at the Sedgwick Museum, Cambridge, England

A twisted commissure plane is a common feature in several species of the mytilid genus Modiolus. Observations on a semi-infaunal population of M. americanus in Bermuda suggests that the twisted shell morphology maximizes the length of posterior commissure raised above the sediment surface while keeping its profile low, with minimum risk of accidental damage. Thus, the shell morphology in the twisted Mytilidae represents adaptive convergence with the twisted Arcidae and Bakevelliidae.

• Read more about Adaptive significance of shell torsion in mytilid bivalves

This is the first detailed account of the trilobites from the platformal carbonate/clastic Nora Formation of central Australia. The fauna records a remarkable, endemic radiation of the Family Asaphidae, producing forms with inflated, tuberculate frontal glabellar lobes unlike any other asaphids, but with a general resemblance to certain unrelated trilobites which lived in former epeiric habitats. The fauna is probably of mid-late Arenig age.

• Read more about Early Ordovician trilobites, Nora Formation, central Australia

Coilopoceras requienianum (d'Orbigny, 1841) is revised on the basis of the types and other material. It shows wide intraspecific variation and dimorphism of the type demonstrated in North American species of the genus. Similar dimorphism is shown in other Old World species, especially Nigerian forms, with Glebosoceras Reyment, 1954, a strongly ornamented genus which is treated as a synonym of Coilopoceras Hyatt, 1903.

• Read more about The Cretaceous ammonite Ammonites requienianus d'Orbigny, 1841

The anatomical characters of some European Bathonian charophyte gyrogonites have been studied. The presence of a multipartite basal plate in representatives of the Porocharaceae/Porocharoideae justifies the creation of a new genus, Musacchiella gen. nov., represented by three new species: M. douzensis, M. palmeri, M. sp. A. No clear relationship has been demonstrated with extant and fossil Characeae/Nitelloideae in which a multipartite basal plate is also to be found. On the other hand, the outline of the apical pore suggests relationships with the family Raskyellaceae.

• Read more about New Porocharaceae from the Bathonian of Europe: phylogeny and palaeoecology

New records of northern hemisphere plant genera are described from the Lower Plant Assemblage (Late Silurian, Ludlovian) and the Wilson Creek Shale (Early Devonian, Pragian/Siegenian) of Victoria, Australia. The genera, the rhyniophyte Salopella of which there are two new species S. australis and S. caespitosa, and Dawsonites, represented by D. subarcuatus sp. nov., which is the first recording of a trimerophyte in Victoria and probably in the Southern Hemisphere, were found associated with Baragwanathia and are new additions to the Baragwanathia flora.

• Read more about Rhyniophytina and Trimerophytina from the early land flora of Victoria, Australia

In contrast to the minor within-habitat improvements in shell shape and sculpture of primary soft-bottom dwellers, the transition of fixosessile rock dwellers back to soft substrates has resulted in fast and drastic morphological changes. They were facilitated by the available ecologic stepping stones that caused morphogenetic programmes—first to 'derail' (rock habitats), then to be shortened (to fit the size of dead shell habitats), and finally to extend again (in order to increase mechanical stability on soft bottoms).

• Read more about Constructional morphology of bivalves: evolutionary pathways in primary versus secondary soft-bottom dwellers [twenty-fourth annual address, delivered 10 March 1983]

Trilobites of the family Odontopleuridae are described from the Silurian of Gotland, Sweden. Twelve species and subspecies (nine named, of which four are new) are assigned to four genera. Anacaenaspis gotlandensis Bruton, 1967 is considered to be a junior subjective synonym of Acidaspis pectinata Angelin, 1854, which is therefore the type species of the genus. Primaspis (Taemasaspis) Chatterton, 1971 is regarded as a junior subjective synonym of Dudleyaspis, which in addition to the nominate subgenus includes D. (Snoderaspis) subgen. nov. Ceratocephala barrandii (Fletcher in Salter, 1853), A.

• Read more about Silurian odontopleurid trilobites from Gotland