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The occurrence and morphology of fenestrate ovicells is reviewed and ovicells are described for the first time in Penniretepora. Four ovicell types are recognized and the considerable variation in morphology, size, position, and intra-colonial abundance of ovicells at generic level is related to variation in the morphology of autozooecial chambers, proximity of autozooecia, and the number of autozooecial rows on branches and dissepiments.

• Read more about Ovicells in the Palaeozoic bryozoan order Fenestrata

Two new genera of Triassic sphenodontid are described. Sigmala sigmala gen. et sp. nov. and Pelecymala robustus gen. et sp. nov. occur in fissure deposits in Cromhall Quarry, south Gloucestershire. They are based entirely on dissociated jaw elements. Five sphenodontid genera have now been described from this locality and they permit a review of sphenodontid systematics. Based principally on dental morphology, an updated classification of the Sphenodontidae is offered.

• Read more about New Triassic sphenodontids from south-west England and a review of their classification

Konbostrea (gen. nov.) is an aberrant oyster of the Crassostrea group, characterized by its dorsoventrally elongated stick-like shell. It is found in life position, perpendicular to the bedding in brackish-water muddy deposits of the Upper Turonian to Upper Coniacian, in Sakhalin and north Japan. A narrow body space is restricted to the ventral end of the shell. The ligamental area is very small, separated from the body space, and the ligament is considered to have been active only during the younger stages of growth.

• Read more about Shell structure, growth, and functional morphology of an elongate Cretaceous oyster

The first detailed investigation of a probable noctidiurnal growth rhythm of the tubular oscillatoriacean cyanophyte Siphonophycus inornatum Y. Zhang, in stratiform stromatolites of the mid-Proterozoic Gaoyuzhuang Formation (c. 1400-1500 ma), Hebei Province, North China, is presented herein. The sequence consists of light, thick, silica-filled layers alternating with dark, thinner, algal-rich layers. The filaments exhibit a distinct, layered pattern of horizontally orientated populations alternating with vertically orientated populations.

• Read more about Solar cyclicity in the Precambrian microfossil record

The fossil and Recent fish fauna of the Antarctic region is systematically and biogeographically reviewed. The occurrence of Pristiophoridae, Chimaeriformes, and Siluriformes is reported from the Antarctic region for the first time. The pristiophorids, chimaeriformes, and previously reported Antarctic shark fossils show that although chondrichthyans are a minor component of the Recent Antarctic fauna, they are very diverse in the Lower Tertiary fossil record of the continent.

• Read more about A review of Antarctic ichthyofaunas in the light of new fossil discoveries

The Calcaire a Baculites of the Cotentin Peninsula, Manche, France, is a sequence of bioclastic limestones occurring as isolated outliers resting unconformably on rocks of Precambrian to Cenomanian age. Ammonites, chiefly Baculites, are locally abundant, and their taxonomy is revised. B. anceps Lamarck, 1822 dominates the fauna, with scarce Hoploscaphites constrictus (J. Sowerby, 1817) and rare to very rare Pachydiscus (Pachydiscus) gollevillensis (d'Orbigny, 1850), P. (P.) jacquoti Seunes, 1890, P. (P.) sp., P.

• Read more about The ammonite fauna of the Calcaire à Baculites (Upper Maastrichtian) of the Cotentin Peninsula (Manche, France)

The morphologically divergent and long-ranging Calceocrinidae (inadunate crinoids, middle Ordovician to early Permian) are reinterpreted to have been leeward, passive, suspension feeders. Calceocrinid success is measured relatively by species diversity and by the relationship of calceocrinid species diversity to total crinoid generic diversity. The major change in calceocrinid importance occurred immediately after the Silurian, and this decline is judged to have been the consequence of biotic interactions.

• Read more about Palaeoecology and history of the Calceocrinidae (Palaezoic Crinoidea)

Recent developments in molecular biology are beginning to provide new ways of looking at the history of life. At present there are three main potential sources of information: organic molecules extracted from rocks or fossils, the comparative molecular biology of living organisms, and the knowledge that is developing about the role of biopolymers in the construction of skeletons. Each of these fields is reviewed briefly to illustrate how the information that is becoming available may be used in future to serve the common goals of palaeontology and molecular biology.

• Read more about Molecular palaeontology

The type material of Calymene blumenbachii Brongniart in Desmarest 1817 (type species of Calymene Brongniart, 1822) and C. tuberculata (Brunnich, 1781) has been revised, with that of the latter being figured for the first time. The nomen dubium status accorded to C. tuberculata by Shirley (1933) can no longer be upheld as the syntype specimens of Silurian age are, on preparation, very well preserved and identifiable, though this species is now recognized as a senior (subjective) synonym of C. blumenbachii.

• Read more about The type species of Calymene (Trilobita) from the Silurian of Dudley, England

Hesperoherpeton garnettense Peabody was first described as an embolomerous anthracosaurian amphibian, based on a small scapulocoracoid and associated neural arch from the Upper Pennsylvanian of Garnett, Kansas. Subsequently, on the basis of a referred specimen from the type locality, Hesperoherpeton was claimed by Eaton and Stewart to be the most anatomically primitive tetrapod despite its Upper Pennsylvanian age.

• Read more about On the identity of the amphibian Hesperoherpeton garnettense from the Upper Pennsylvanian of Kansas