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A new alga from the Frosterley Marble (Namurian; Carboniferous) of northern England is reconstructed from fragmentary material. It is compared with the Carboniferous genera Kulikia and Sphinctoporella, sharing with them the distinctive profusion of spherical cavities within the calcined axial surround or 'sleeve'. It differs from them in being formed of successional separate calcified discs or verticil units, which came apart after death, and is thus described as Frosterleyella diaspora gen. et sp. nov.

• Read more about A new alga from the Carboniferous Frosterley Marble of northern England

The Tremadoc trilobite fauna from the Skiddaw Group exposed in the river Calder, western Lake District, consists of ten species and is referred to the upper Tremadoc Angelina sedgwickii Biozone. Some of the constituent genera are of wide geographical range in outer shelf environments. Two species, Pareuloma expansum and Prospectatrix brevior, are new.

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New material of one of the oldest known tetrapods, Acanthostega gunnari, is described: three skulls, together in one block, in association with postcranial material. This is the first postcranial material to be described for Acanthostega. The skulls show an animal with a broad, closed, denticulated palate in which the pterygoids meet in the mid-line as in loxommatids and Ichthyostega. The ventrally grooved parasphenoid resembles that of some osteolepiform fish rather than that of tetrapods. The basal articulation is tetrapod-like with well-developed basipterygoid processes.

• Read more about New material of the early tetrapod Acanthostega from the Upper Devonian of East Greenland

Palaeocorynid-type structures (Family Palaeocorynidae Duncan and Jenkins 1869), currently regarded as being of uncertain zoological affinities, are here interpreted as being a specialized form-appendage of Upper Palaeozoic fenestellid Bryozoa. Palaeocorynid-type appendages are morphologically complex, and consist of a short stem developed at right angles from the branch of the bryozoan, terminating in a cone-shaped body from whose lateral margins a variable number of long slender spines or branchlets emanate at high angles.

• Read more about Palaeocorynid-type appendages in Upper Palaeozoic fenestellid Bryozoa

In the extreme south-east of Turkey the Sort Tepe Formation rests disconformably on Arenig strata of the highest Seydisehir Formation. Trilobites are described from the stratotype of the Sort Tepe Formation and a supplementary section, both on the north-east side of the Zap Valley, 40 km south-south-west of Hakkari. The twenty taxa described include three new species: Sinocybele? fluminis, Calymenesun longinasuta, and Paraphillipsinella piluea. The assemblages, of early Ashgill, probably Pusgillian or possibly Cautleyan, age, consist mainly of genera widespread in Europe.

• Read more about Upper Ordovician trilobites from the Zap Valley, south-east Turkey

A new cephalopod genus, Torquatoceras, comprising two new species T. undulatum and T. auritum, is described from the Silurian of Gotland. Torquatoceras is unique in that transverse crenulated frills have been secreted during the entire growth of the shell. These frills, mainly consisting of prismatic layers, might have served as a reinforcement of the shell. In T. undulatum sexual dimorphism based on size variations is demonstrated. In T. auritum there are two vertical septa inside the body-chamber, partly separating the hyponomic sinus from the apertural opening.

• Read more about A Silurian cephalopod genus with a reinforced frilled shell

A restudy of Duslia insignis Jahn, 1893 from the Upper Ordovician of the Barrandian area, Bohemia, indicates that this trilobate arthropod, originally referred to polyplacophorans, cannot be assigned to true trilobites but shows some morphological analogies with Cheloniellon, Pseudarthron, and Triopus. Duslia inhabited a nearshore shallow marine environment and was probably a benthic animal which lived buried in sandy substrate near the sediment-water interface.

• Read more about The enigmatic arthropod Duslia from the Ordovician of Czechoslovakia

Disassociated assemblages from the Mesozoic of South-west Britain display considerable variation both in the numbers of species present and in their distribution. Triassic fissure deposits at Cromhall Quarry, Avon have yielded abundant reptilian remains which for the most part are readily identified to generic level. These sediments have also revealed some very rare and quite unusual skeletal elements, including jaw bones and a procoelous vertebra. These could be prolacertiform, thalattosaurian, or pterosaurian remains, but the nature of the material makes taxonomic diagnoses difficult.

• Read more about Rare tetrapod remains from the late Triassic fissure infillings of Cromhall Quarry, Avon

Restorations of the cephala of species of each of eighteen genera show the hypostome and cephalic sutures; new photographs are given of these features in Holmia, Bathynotus, Paradoxides, Fieldaspis, Ptychoparia, Conocoryphe, and Agraulos. It is considered that probably in all trilobites the tip of the upwardly directed anterior wing of the hypostome was situated close beneath the ridge formed on the internal surface of the cephalon by the axial furrow, in a position immediately in front of where the eye ridge or eye lobe met this furrow.

• Read more about Hypostomes and ventral cephalic sutures in Cambrian trilobites

The common Chalk anascan Herpetopora has runner-like encrusting colonies with uniserial branches. Following larval settlement, the ancestrula, described for the first time, budded two daughter zooids to initiate two first order colony branches which grew in opposite directions. Branches of higher orders were added by lateral zooidal budding from both sides of parent branches, usually at c. 80°. The 'mature' colony consisted of two conjugate sets of branches. Size/frequency distributions of zooidal length in H.

• Read more about Colony growth patttern and astogenetic gradients in the Cretaceous cheilostome bryozoan Herpetopora