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Monocycloides oelandicus gen. et sp. nov. is described from upper Arenig age beds on Oland, Sweden (Volkhov Stage, Langevoja Substage). The genus is monotypic and is the earliest known cyclocystoid echinoderm. Palaeogeographical origins of the cyclocystoids remain uncertain, but Monocycloides is regarded as a primitive sister group of the North American Ordovician Cyclocystoides.

• Read more about A new cyclocystoid from the Lower Ordovician of Öland, Sweden

A rich ammonite fauna is described from the basal Turonian Pseudaspidoceras flexuosum Zone of west Texas. Taxa present include typically Boreal, Tethyan, and US Western Interior species and widely occurring forms of the bivalve Mytiloides. This co-occurrence of key species from different faunal realms and provinces provides a basis for correlation of the base of the Turonian stage. Species present are the ammonites Quitmaniceras reaseri Powell, 1963, Kamerunoceras calvertense Powell, 1963, Pseudaspidoceras flexuosum Powell, 1963, Mammitespowelli sp.

• Read more about Basal Turonian Ammonites from west Texas

Four neocatastrophist claims about mass extinction are currently being debated; they are that: 1, the late Cretaceous mass extinction was caused by large body impact; 2, as many as five other major extinctions were caused by impact; 3, the timing of extinction events since the Permian is uniformly periodic; and 4, the ages of impact craters on Earth are also periodic and in phase with the extinctions. Although strongly interconnected the four claims are independent in the sense that none depends on the others.

• Read more about Mass extinction: a commentary [twenty-ninth annual address, delivered 19 March 1986]

Two specimens from the Low Main Seam at Newsham, Northumberland are attributed to the genus Anthracosaurus. The first is a skull table (Hancock Museum specimen G 13.78) previously attributed to 'Eogyrinus' (= Pholiderpeton, Clack 1987). This skull table was used in the past to demonstrate the presence of a 'kinetic line' between the embolomere skull table and cheek. The holotype of A.

• Read more about Two new specimens of Anthracosaurus (Amphibia: Anthracosauria) from the Northumberland Coal Measures

• Read more about New late Palaeozoic Hyolitha (Mollusca) from Oklahoma and Texas, and their palaeoenvironmental significance: erratum

Although dissociated ossicles are locally common in the Upper Permian, Zechstein Cycle 1, Ford Formation reef of north-east England, the crinoid fauna is monospecific, consisting of 'Cyathocrinites' ramosus (Schlotheim). This species differs from Cyathocrinites s. s. in having a broad, bowl-shaped cup with wide radial arm facets and the right proximal plate of the anal tube incorporated into the calyx. The taxonomic position of 'C.' ramosus below order level is uncertain.

• Read more about The British Permian crinoid 'Cyathocrinites' ramosus (Schlotheim)

Calcified lophophore supports present in the oldest of the spire-bearing brachiopods, the Lissatrypidae which range in age from middle Ordovician (Caradoc) through middle Silurian (Wenlock) time, demonstrate complex evolutionary patterns and early divergence. The smooth-shelled brachiopods Protozyga, Idiospira, and Cydospira, which had medially or dorso-medially directed spiralia, evolved from the primitive early Caradoc atrypoid Manespira n. gen., which had a spiralium of less than one whorl and a whole or partial jugum. Early divergence produced four separate lineages, the Protozyginae n.

• Read more about Evolution of the earliest smooth spire-bearing atrypoids (Brachiopoda: Lissatrypidae, Ordovician–Silurian)

A new technique is described for the preparation of sections of anatomically preserved plant fossils starting from the simple and well-known cellulose acetate peel method. Improvements of the results obtained by the peel method are described whereby use of very dilute acid allows extraction and observation in planar view of cell walls that are almost always destroyed by traditional methods. The Disappearing Peel Technique has been especially developed for histological investigations of the delicate cell walls of extra-xylary vascular tissue.

• Read more about The disappearing peel technique: an improved method for studying permineralized plant tissues

Individual spherical bodies from a richly algal deposit in the Palaeocene-Lower Eocene of Kurdistan are described in detail and interpreted as detached cysts from a dasycladalean alga believed to resemble Halicoryne (Cenozoic-Recent). The fossils are named Sedalanella segonzacae gen. et sp. nov.

• Read more about Isolated algal cysts in the Palaeocene–Lower Eocene of Kurdistan

Two trilobite assemblages of middle Llandeilo to basal Caradoc and of Caradoc age are described from the type section of the Chedao Formation at Chedao, Huanxian County, Gansu Province, north-west China. They include twenty-nine taxa, of which five are new species: Phorocephala quadrata, Peraspis obscura, Microparia (Quadrapyge) chedaoensis, Ischyrophyma? zhiqiangi, and Hammatocnemis obsoletus. The composition of both assemblages approaches that of the Nileid Association and suggests that the Huanxian area formed part of the western slope of the North China carbonate platform.

• Read more about Ordovician trilobites from Chedao, Gansu Province, north-west China