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Colpodecrinus forbesi sp. nov. is founded on the evidence of unusual tetrameric crinoid columnals similar to those of C. quadrifidus Sprinkle and Kolata. The columnals of C. forbesi have quadrangular lumina, either tetrastellate or square, whereas those of C. quadrifidus are tetralobate.

• Read more about Tetrameric crinoid columnals from the Ordovician of Wales

Specimens of the tentaculitoidean Nowakia brevis sp. nov. are described from the type locality of Monograptus sedgwickii (Portlock) in the Silurian of Pomeroy, Co. Tyrone, Ireland. This is the oldest known representative of the Nowakiidae, a family not known again in the fossil record until the early Devonian.

• Read more about The oldest known nowakiid (Tentaculitoidea)

Neoselachian sharks' teeth from the lower Jurassic of Lyme Regis, Dorset, are described am assigned to Agaleus dorsetensis gen. et sp. nov. The teeth are large, and have a robust central cusp, one pair of lateral cusplets, and a prominent basal flange. Longitudinal ridges are present on the labial crown shoulder and the root has a strong labial buttress. The vascularization is hemiaulacorhize. Comparison with the teeth of Recent and fossil neoselachians indicates that Agaleus is a benthonic orectolobiform galeomorph.

• Read more about Teeth of a new neoselachian shark from the British Lower Jurassic

A new collection of coprolites exhibiting spiral markings from the upper Triassic Maleri Formation in the Pranhita-Godavari valley of southern India is critically examined. An attempt is made to relate their internal structure to the Maleri faunal elements. Ceratodus is a conspicuous member of the Maleri fauna. Some anatomical features such as the morphology of the spiral valve and faeces and the relationship between dental plates and body size in living Neoceratodus forsteri have been examined.

• Read more about Spirally coiled 'coprolites' from the Upper Triassic Maleri Formation, India

The putative Jamaican octodontid rodent AIterodon major is based on a single cheek tooth. Restudy of this specimen indicates that it is probably incomplete, and that it is much more likely to represent a heptaxodontid than an octodontid. If this inference is correct, then there is no longer any reason to believe that there was an independent octodontid invasion of Jamaica. Although this clears up one biogeographical puzzle, no new light is shed thereby on the origins and dispersals of Caribbean land mammals.

• Read more about The Pleistocene rodent Alterodon major and the mammalian biogeography of Jamaica

The Entomozoacea ('entomozoids') are an important group of Palaeozoic ostracods which flourished in the upper Devonian and lower Carboniferous. Although they have traditionally been regarded as planktonic, the carapace morphology of the entomozoaceans provides no clear evidence for either a planktonic or benthic existence and it is concluded that both these modes of life may have been represented within the group. This paper is the first significant published account of these ostracods in the British Carboniferous.

• Read more about Entomozoacean ostracods from the Lower Carboniferous of south-western England

Suturovagina intermedia Chow and Tsao (Cheirolepidiaceae) from the Cretaceous of China is redescribed and emended on the basis of abundant new material. Its leafy shoots are heterophyllous and show axillary branching. The juvenile shoots bear widely spaced scale leaves, while mature ones bear mainly broad leaves enclosing most or the whole of the stem, with either a gap or a suture between the two lateral edges. Leaves of different types of shoot are generally similar in cuticular structures.

• Read more about A heterophyllous cheirolepidiaceous conifer from the Cretaceous of East China

The assumption of a constant positional relationship between dermal bones and endocranial structures, which constitutes the basis for the main arguments of proponents of three suggested solutions concerning the correct homologies of the medial exocranial bones of tetrapods and osteolepiform fishes, is discussed and criticized. It is shown that, by disregarding this assumption, these homologies are easily understood.

• Read more about Homologizations of skull roofing bones between tetrapods and osteolepiform fishes

The jaw apparatuses of three late Cretaceous desmoceratines (Tragodesmoceroides subcostal Damesites ainuanus, and D. semicostatus) are described and compared with those of other ammonites and modern cephalopods. The jaws of the three species morphologically resemble one another, and belong to the anaptychus-type jaws of Lehmann (1981), because of the fundamental jaw structures and the absence of a calcareous element. Based on comparison of jaw structures with modern cephalopods and the jaw-muscle relations in modern Nautilus, a possible buccal structure of the Desmoceratinae is proposed.

• Read more about The jaw apparatuses of Cretaceous desmoceratid ammonites

The directly attached diploporite cystoid Sphaeronites is characterized by a closely approximated mouth and anus on an oral platform, and densely developed diplopores. Three subgenera are recognized: Sphaeronites s.s. (lower Ordovician, Sweden); Peritaphros (middle and upper Ordovician, Britain, Norway, Sweden, Baltic States); Ataphros subgen. nov. (upper Ordovician, South Wales). Early species occur in 'Sphaeronites beds' with few other echinoderms. Later species are less abundant, but occur with a more diverse echinoderm fauna.

• Read more about Evolution and functional morphology of the cystoid Sphaeronites in Britain and Scandinavia