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The London Clay of Sheppey, Kent, is a grey plastic clay which was deposited in an offshore marine environment. It contains a diverse assemblage of well-preserved plant and animal fossils in concretions of either pyrite, apatite, or calcite. A diagenetic and geochemical study of the London Clay biota shows that apatite was the first preservational mineral to form, followed by calcite and pyrite. Mineralogy is strongly related to original biological composition. Only those organisms with an original skeletal phosphate content (i.e. vertebrates and arthropods) have been phosphatized.

• Read more about Taphonomy of the Eocene London Clay biota

Theoretical models of heterochronic processes are based on the comparison of ontogenetic age-shape curves of ancestor and descendant. An existing principal components analysis of an exhaustive body of Namurian ammonoid morphological data is a suitable source of information for assessment of heterochrony in this context. Using size as an indicator of age and principal component score as a shape index, heterochronic analyses of two evolutionary radiations of the Gastriocerataceae demonstrate that one was strongly influenced by neoteny, the other by acceleration.

• Read more about Heterochronic trends in Namurian ammonoid evolution

A new scotiaecystid, Scotiaecystis collapsa sp. nov. is described from the Killey Bridge Beds, lower Cautleyan Stage, Ashgill Series, near Pomeroy, Co. Tyrone, Northern Ireland. It is most closely related to S. curvata Bather. The interrelations of cornutes are studied through a cladistic analysis using PAUP (Phylogenetic Analysis Using Parsimony) involving twenty-one species and thirty-nine characters. Three equally parsimonious trees are obtained and their information content summarized in the form of a consensus tree.

• Read more about A new species of stem-group chordate from the Upper Ordovician of Northern Ireland

The missing holotype of the conifer Brachyphyllun punctatum Michael originally described from the Wealden of Germany has been rediscovered. B. castatum Watson, Fisher and Hall from the English Wealden has proved to be synonymous with B. punctatum. Tarphyderma glabra Archangelsky and Taylor from the Lower Cretaceous of Argentina is probably also specifically identical.

• Read more about The holotype of the Wealden conifer Brachyphyllum punctatum Michael

The functional morphology of the elongated neck of Tanystropheus longobardicus (Bassani) has long been controversial. It is suggested here, that the neck was not very flexible because the elongated cervical ribs are bundled along the ventrolateral margin of the vertebrae. The result, a stiffened neck, is advantageous in an aquatic environment. The ontogenetic development of the neck in T. longobardicus and Macrocnemus bassanii Nopcsa, both included within the Prolacertiformes, is another point of interest.

• Read more about Allometry and heterochrony in the growth of the neck of Triassic prolacertiform reptiles

Biological studies have indicated that the oysters Crassostrea virginica (Gmelin) and C. rhizophorae (Guilding) may be a single species. This is surprising as they are morphologically dissimilar, C. virginica being far larger and thicker than C. rhizophorae. We postulate that this variation may be ecophenotypic in origin, a cause of gross variation in form in other oysters. To test our hypothesis, we have compared the palaeoecology and ecology of Plio-Pleistocene C. virginica and Recent C. rhizophorae from Jamaica. A spectacular Plio-Pleistocene deposit is dominated by C.

• Read more about Variation of Recent and fossil Crassostrea in Jamaica

The Upper Permian reptile Adelosaurus from the Marl Slate of Durham, England, is redescribed and compared with contemporary genera. The study confirms Watson's (1914) conclusion that Adelosaurus is generically distinct from Protorosaurus to which it was originally referred. The skeleton seems immature, and shows a combination of primitive and derived character states. Amongst the latter, are the possession of a strong humerus with little proximal or distal expansion, and of a slender sigmoidal femur and triangular ilium, character states shared with diapsids.

• Read more about The Upper Permian reptile Adelosaurus from Durham

Fossil Isognomonidae (Pteriacea) can be difficult to distinguish externally from the biostratigraphically important Mesozoic family Inoceramidae (Ambonychiacea?). Internal details of ligament area morphology provide valuable taxonomic data at the family and species levels, as documented for many New Zealand species. Definitive distinction between these two families is furnished by the shell structure underlying the ligament area: in Isognomonidae the ligament attaches to the inner (presumed nacreous) shell layer, whereas in Inoceramidae it attaches to the outer prismatic shell layer.

• Read more about Comparative taxonomy of the bivalve families Isognomonidae, Inoceramidae, and Retroceramidae

The skull of a new weigeltisaurid reptile, Wapitisaurus problematicus gen. et sp. nov., from the Lower Triassic Vega-Phoroso Member of the Sulphur Mountain Formation is described. It shares with Coelurosauravus, the only other known weigeltisaurid, the presence of an incomplete lower temporal arcade, a jugal with reduced postorbital process, and a squamosal crest ornamented with tooth-like projections. It differs from Coelurosauravus in its large size and in the structure and implantation of the teeth.

• Read more about A weigeltisaurid reptile from the Lower Triassic of British Columbia

Eleven trilobite species are described from the Upper Cambrian-basal Ordovician succession exposed to the south-eastern side of Koonenberry Mountain in western New South Wales. Included among the forms are six new species, Rhaptagnostus leitchi, Pareuloma aculeatum, Pseudoyuepingia whitei, P. lata, Proceratopyge ocella, and Hysterolenus furcatus. The assemblages come from two stratigraphically distinct horizons near the top of the Watties Bore Formation.

• Read more about Upper Cambrian and basal Ordovician trilobites from western New South Wales