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Azendohsaurus laaroussii was described by Dutuit as an ornithischian dinosaur on the basis of a dentary fragment and two isolated teeth from the Upper Triassic Argana Formation of Morocco. It was subsequently suggested to be a mixture of ornithischian and saurischian remains. Study of further material demonstrates that all the A. laaroussii material represents a single valid taxon within the Prosauropoda. However, there is insufficient taxonomic information to place it more precisely and it is considered as Prosauropoda incertae sedis. A.

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The Lower Cambrian genus Bigotina is reinvestigated on the basis of new material (including larval stages and pygidia) from the type locality of B. bivallata, from the upper third of the Saint-Jean-de-la-Riviere Formation (Carteret, Normandy, France). A neotype for B. bivallata is proposed. The new material clarifies the generic concept of this very early trilobite which exemplifies the primitive morphology of non-olenellid trilobites.

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Postmetamorphic ontogeny of the nasal region in trematopid amphibians (Temnospondyli: Dissorophoidea) from the Lower Permian of Texas is characterized by the early appearance of a narial flange which is identical to that of an adult. Subsequent ontogenetic changes are the posterior expansion of the external naris, positive allometric growth of rostral length, and the development of caniniform teeth on the premaxillae and maxillae.

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Despite their importance in articulate brachiopod evolutionary history, relatively little is known in detail about the phylogenetic relationships among 'pentameride' taxa, and of ' pentamerides' to other articulates. Phylogenetic relationships among all named 'pentameride' families and rhynchonellide superfamilies were reanalysed using outgroup methods of polarity determination. A detailed working hypothesis of 'pentameride' phylogeny and the supporting evidence on character distribution is presented.

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Problematical microfossils are described from the Silurian of the Dingle Peninsula, County Kerry, Ireland and from a clast in the Old Red Sandstone Greywacke Conglomerate of the Midland Valley of Scotland. They are assigned to Sandvikina under the new specific name conica. The Irish material includes also single specimens of Sandvikina sp. and Regnellia camera. All these microfossils, which appear to be closely related, are here assigned to the new family Regnellidae, which, on present evidence, is characteristic of the Silurian.

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The eodiscid Shizhudiscus longquanensis occurs abundantly in the Lower Cambrian Shuijintuo Formation, Pengshui, Sichuan, China. Phosphatized specimens in excellent preservation have been isolated from a single limestone lens, and include a few protaspides and disarticulated examples of all subsequent growth stages. From this material the ontogeny of S. longquanensis is described and reconstructed. Of particular note are two large spines on the axis of the transitory pygidium which eventually become thosi of the second and third thoracic segments.

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A revision of the Pterygometopinae from Baltoscandia has revealed that the subfamily is more diverse at the generic level than previously known. New genera are Ingriops, Oelandiops, Upplandiops, and Keilapyge. The earliest species of Achatella are included in the new subgenus A. (Vironiaspis). The new species Oelandiops mirificus, Upplandiops calvus, Estoniops maennili, and E. fjaeckensis are described. Upplandiops calvus differs from most other dalmanitaceans in having only ten thoracic segments.

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Durophagous crabs were found to make unusually high rates of predatory mistakes by attacking empty gastropods and models of intact bivalves. This mistaken predation is attributed to the crypticity of the shell: if a crab cannot readily determine whether a shell contains food, as is the case with gastropod shells, it will crush it. In contrast, empty bivalve shells (represented by half-shells) are readily examined by crabs and rejected. The taphonomic implications, and importance for the gastropod fossil record, are two-fold.

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Devonian tetrapod remains have been recovered from the Famennian of Russia. They occurred in a limestone with stromatolites, algae, numerous and diverse fish remains and the holotype of the tetrapod Tulerpeton curtum. The conditions indicate a shallow-water basin with carbonate-rich water and perhaps an estuarine or marine situation.

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The Carboniferous temnospondyl amphibian Capetus palustris is reassessed on the basis of new and previously described specimens from the Gaskohle of Nyrany, Czech Republic. Capetus has frequently been synonymized with Gaudrya, also from Nyrany, but the holotype of Gaudrya is a fragment of a large specimen of Cochleosaurus. The phylogenetic position of Capetus within the primitive temnospondyls is uncertain and there is no support for a cladistic relationship to the typical long-snouted edopoids.

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