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The discovery of new sources of material has enabled restudy of the minute Thecideum pygmaeum Moore, 1861. Although their general organization is close to that of the monoseptal representatives of the Moorellininae the new specimens differ from typical thecideidines in the absence of both dorsal median septum and hemispondylium and in the presence of an incomplete subperipheral rim. The form may prove to be important in tracing the phylogeny of the Thecideidina.

• Read more about The diminutive thecideidine brachiopod Enallothecidea pygmaea (Moore) from the Middle Jurassic of England

Information on the nature, taxonomy, and stratigraphical and geographical distributions of thi dasycladalean algal structure Sarfatiella is summarized. It is suggested that Sarfatiella is the calcifiec reproductive structure of an otherwise non-calcified dasycladalean. Its middle Jurassic palaeogeographical distribution is latitudinally wide and believed to have been subtropical as well as tropical.

• Read more about Distribution and affinities of the Jurassic dasycladalean alga Sarfatiella

Eopachydiscus Wright, 1955 is confirmed as the earliest, Upper Albian representative of the Pachydiscidae, derived in all probability from a bullate member of the Beaudanticeratinae and giving rise to the Cenomanian-Coniacian Lewesiceras Spath, 1939. Nuclei of Eopachydiscus are ribbed, tuberculate, and constricted, showing even at this stage and date typical pachydiscid ornament; the evolution of Lewesiceras simply involved retention of these features into middle growth.

• Read more about The Cretaceous ammonite Eopachydiscus and the origin of the Pachydiscidae

The strata at Dob's Linn from the Extraordinarius Band of the Upper Hartfell Shale Formation to 2.3 m above the base of the Birkhill Shale Formation and their contained taxa are described and accurate faunal ranges provided. The boundary separating the Climacograptus? extraordinarius and Glyptograptus persculptus zones occurs within a 1.17 m thick unfossiliferous part of the succession. The boundary between the G. persculptus and Parakidograptus acuminatus zones is defined at 1.6 m above the base of the Birkhill Shale in the Linn Branch section, where Akidograptus ascensus and P.

• Read more about The Ordovician-Silurian boundary graptolite fauna of Dob's Linn, southern Scotland

The borehole penetrated beds with a lower Llanvirn fauna containing Glyptograptus cf. denatus (Brongniart), some other small and unidentified diplograptids, a Paraulograptus? sp., Didymograptus pluto sp. nov. (pendent), and a Didymograptus sp. (extensiform). The assemblage is quite different from others in Britain, but matches well with several from the Baltic and east European regions. D. pluto is described, with details of its proximal development, astogeny, and intrapopulation variation. Comparisons with D. bifidus (J. Hall) and D.

• Read more about Ordovician graptolites from the Great Paxton borehole, Cambridgeshire

A new genus of procolophonid, Eumetabolodon, from the lower Triassic of Inner Mongolia, China, is described; E. bathycephalus (sp. nov.) is the type-species of the new genus and E. dongshengensis (sp. nov.) is also referred to that genus. Eumetabolodon is characterized by its very deep skull, large orbit, and by the posterior position of the articulation for the lower jaw. The dental morphology, the tooth wear, and the evidence of tooth replacement in this animal are also described in detail.

• Read more about Tooth replacement in a new genus of procolophonid from the early Triassic of China

Analyses of upper Ordovician (Caradoc) shelly faunas from Snowdonia, North Wales, reveal a remarkable diversity of crinoid columnals. So far, fifty-one columnal morphotypes have been recognized am these are listed, illustrated, and described. The morphotypes are categorized on the basis of earlier schemes of classification. The morphotype diversity implies that the original crinoid faunas were varied.

• Read more about Crinoid ossicles in Upper Ordovician benthic marine assemblages from Snowdonia, North Wales

The current debate on the processes of evolution is related to the author's knowledge of the phylum Brachiopoda in Mesozoic strata. An example is presented from the genus Homoeorhynchia in which marginal populations seem to have developed that eventually led to an ecological 'take-over' by a new species.

• Read more about Allopatric speciation—an example from the Mesozoic Brachiopoda

Genera and species in the family Alatoconchidae are described and reillustrated, including a major revision of the type genus, and a family concept is established that transfers them from the Megalodontacea to the Ambonychiacea. Saikraconcha n. gen., with S. tunisiensis n. sp. as type species, and Dereconcha n. subgen., with S. (D.) kamparensis n. sp. as type species, are described. Two lineages are present in the family, with one including Shikamaia and its subgenera Alatoconcha and Tanchintongia, and the other including Saikraconcha and its subgenus Dereconcha.

• Read more about Revision of the Alatoconchidae: a remarkable family of Permian bivalves

The silicified Blackdown Greensand fauna of the Albian in south-west England affords an opportunity for a quantitative assessment of a rich and diverse Cretaceous molluscan fauna. Among its Meso-and Neogastropoda are species of naticids and muricids, as well as numerous Opisthobranchia, all of which today are active predators upon invertebrate prey. Drill holes (amongst the earliest yet recorded) into shelled prey provide evidence of their feeding activities.

• Read more about Predatory gastropods and their activities in the Blackdown Greensand (Albian) of England