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The structure of the brachial valve of four Recent species of terebratuloids was investigated by techniques involving both electron microscopy and light microscopy. The combined approach reaffirmed the conclusions of some previous workers and provided new data on shell growth.The interpretation of patterns observed when sections are cut through the shells is complicated not only by the spatial orientation of the section itself, but by the habit of the truncated crystals as well.

• Read more about Shell-growth in Recent terebratuloid Brachiopoda

The family Marisastridae Rozkowska 1965 is emended. Species of Marisastrum, Haplothecia, and Billingsastraea?, including H. ogwellensis sp. nov., are described from the Middle and Upper Devonian of south-east Devon.

• Read more about Marisastridae (Rugosa) from south-east Devonshire, England

All of the presently known Silurian odontopleurid material from Sweden has been revised along with recently collected material from Estonia and Latvia. For the first time photographs are given of the holotypes of Odontopleura ovata Emmrich and Leonaspis mutica (Ernmrich). Examination of the latter shows that it is specifically distinct from the Swedish species L. marklini (Angelin) and the British species L. coronata (Salter). Addaspis hughesi Lake is considered to be a synonym of O. ovata. The new genus Anacaenaspis (type species A. gotlandensis gen. et sp.

• Read more about Silurian odontopleurid trilobites from Sweden, Estonia, and Latvia

Eleven species and two subspecies in six genera of stropheodontid brachiopods are described from the Upper Llandovery (Lower Silurian) of the Welsh Borderland. Five species and one subspecies are new: Leptostrophia ostrina, L. voraginis and subspecies palustris, Amphistrophia whittardi, Pholidostrophia salopiensis, and Megastrophia ethica; the latter is also made the type of a new subgenus Eomegastrophia. New information has been gained on the phylogeny of the family.

• Read more about Llandovery stropheodontids from the Welsh Borderland

Nine species of megaspores are described from the Geological Survey Wyboston Borehole, Bedfordshire, England. Of these, five species are new, one forming the basis of a new genus, Heliosporites. Two single occurrences of large megaspores referable to Carboniferous genera are recorded, together with a new occurrence of the species Cystosporites devonicus Chaloner and Pettitt. The mean maximum size of all the species represented is 810 p.

• Read more about Devonian megaspores from the Wyboston Borehole, Bedfordshire, England

An examination has been made of the acritarchs, chitinozoa, and spores recovered from the matrix of the primitive echinoid Myriastiches gigas. The results strongly support a Silurian age for the fossil and indicate a Lower Ludlovian horizon.

• Read more about New evidence for the age of the primitive echinoid Myriastiches gigas

Acastella spinosa (Salter 1864) and Acastella? minor (M'Coy 1851) are redescribed and figured. The synonymy of A. spinosa and A. macrocentrus (Reed 1925) is established. A. spinosa is closely compared to other species attributed to the genus. A. prima Tomczykowa 1962 is recorded for the first time from the late Silurian of the British Isles.

• Read more about A revision of Acastella spinosa (Salter 1864) with notes on related trilobites

Cortezorthinae is proposed for the Siegenian-Eifelian septate dalmanellid Cortezorthis gen. nov., its Silurian to Lower Devonian aseptate precursor Protocortezorthis gen. nov., and their derivatives, Reeftonia Allan and Cariniferella Schuchert and Cooper. New species are Protocortezorthis windmillensis and Cortezorthis cortezensis from Nevada and Cortezorthis maclareni and C. bathurstensis from the Canadian Arctic.

• Read more about Cortezorthinae, a new subfamily of Siluro–Devonian dalmanellid

Quaternary fossil microplankton is described from three piston cores taken in the Caribbean Sea. Two cores were from the abyssal plain of the Yucatan Basin in the western Caribbean and the third from the Cariaco Trench, a deep-water depression lying within the continental shelf off Venezuela. This microplankton includes five new genera and eighteen new or reclassified species of dinoflagellates. Its stratigraphic distribution is outlined and its origin and ecology is discussed.

• Read more about Fossil microplankton in deep-sea cores from the Caribbean Sea

The paper describes six species of conodonts assigned to the genus Apatognathus Branson and Meh 1934, from the Yoredale Series of the Askrigg and Alston Blocks in northern England. A ? chaulioda, A ? cuspidata, A? librata, A?petila, and A? scalena are new species, whilst A?gemina (Hinde) is redescribed. The previously recorded occurrences of the genus are listed along with a consideration of possible homeomorphy. The orientation of the genus is reorganized and the distribution of the Yoredale species through the series described.

• Read more about Conodonts of the genus Apatognathus Branson and Mehl from the Yoredale Series of the north of England