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Six species of trilobites from the Upper Llandovery rocks of the Tortworth Inlier are described and figured, including one new species, Proetus asaphoides.

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Recent research has shown that the base of the Great Limestone of northern England lies close to the junction between the Lower and Upper Carboniferous and this stratum has thus gained a new significance. The fauna and lithology of three biostromes, the Chaetetes Band, Brunton Band, and Frosterley Band, which occur persistently in the Great Limestone are described in detail. Two of these, the coralline Chaetetes Band and the algal Brunton Band are new; they are of widespread occurrence in northern England. The Frosterley Band (Dunham 1948) is mainly restricted to the Alston Block.

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The relationships between certain common Mesozoic species of adherent foraminifera are discussed. The wall structure appears to be the deciding factor in the correct placing of these genera. One new genus Arenonina, with type species Arenonina cretacea sp. nov., is proposed. An account of the evolution of the Bullo-pora-Vitriwebbina group is given. Most of the important species of Mesozote adherent foraminifera are figured, although full synonymies are not considered desirable at this stage in our knowledge.

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The microspore genus Simozonotriletes is reinterpreted in the light of new material obtained from three horizons in the Westphalian sequence of Great Britain. The spores are assigned to nine varieties of the type species Simozonotriletes intortus (Waltz). The species S. sublobatus (Waltz) is reduced to varietal status; Triquitrites trivalvis (Waltz) is transferred to Simozonotriletes and also recognized as an infraspecific category. The variation in the spore assemblages is described and the stratigraphical occurrences noted.

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A brief review of the crinoid fauna of the Ludlow formation is followed by the redescription of Eutaxocrinus maccoyanus (Salter) and Meristocrinus orbignyi (M'Coy). The following new species are described: Gissocrinus ludensis, Mastigocrinus bravoniensis, and Hapalocrinus quinquepennis. Pisocrinus cf. sphericus (Rowley) and Cicerocrinus spp. also occur in the fauna.

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Stromatoporoids from the Coral-stromatoporoid beds (Upper Jurassic: Argovian-Rauracian) exposed in the Kurnub Anticline of Maktesh Hathira, southern Israel, are shown to be characterized by lateral astrotubes and considered to be transitional to the Hydroidea. They are described as Actostroma damesini, A. nasri, and A. kiihni, gen. et spp. nov.

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The type specimen of Cephalaspis lyelli, the genotype of Cephalaspis, has never been fully described nor properly figured, and its counterpart has hitherto been completely ignored. Both parts of the specimen have been further developed, especially the counterpart, and are here described in detail. The position of the species in Stensio's proposed new classification is established on the form of the oralo-branchial chamber. No other specimen of this species is known.

• Read more about On Cephalaspis lyelli Agassiz

A distinctive coarse-celled branching coralline alga, characteristic of the Oligocene of the Mediterranean and Middle East, is described as Subterraniphyllum thomasi gen. et. sp. nov. and briefly discussed.

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Alliatina excentrica (di Napoli Alliata) is recorded for the first time from the Pliocene of the Anglo-Belgian basin. The distribution of A. excentrica and Alliatinella gedgravensis in the Pliocene of Europe, and the genus Alliatina in Recent seas is considered. It is concluded that A. excentrica is a warm-water species characteristically inhabiting shallow, sub-littoral environments, and its disappearance from the Anglo-Belgian basin marks the Plio-Pleistocene boundary. The type species of Alliatinella is described and figured, and the genus defined.

• Read more about The distribution of the foraminifer Alliatina excentrica (di Napoli Alliata) and the new genus Alliatinella

Ammonites of the genus Leymeriella Jacob characterize the Northern Hemisphere and are found in neritic deposits of Lower Albian age extending from the Urals to east Greenland. Known occurrences are restricted to the Zone of Leymeriella tardefurcata. Investigation of anomalous records of Leymeriella in the overlying Zone of Douvilleiceras mammillatum discloses that the classic 'Mammillatum' bed of the Ardennes and Meuse Departments of France, which furnished d'Orbigny with much type material, is a condensed deposit in which elements of both Tardefurcata and Mammillatum age are combined.

• Read more about The Cretaceous ammonite genus Leymeriella, with a systematic account of its British occurrences