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Desmophyllum cristagalli has some characteristics in common with other ahermatypic corals living in deep water (2000 m for our specimens). This weakly colonial species is characterized by a theca greatly thickened by deposition of stereome, also forming massive deposits within the corallite and sometimes completely filling it. Septal trabeculae are uniformly small in diameter in this species, and tend to blend into a fine-grained septal 'dark line' when seen in transverse thin section.

• Read more about Structure and incremental growth in the ahermatypic coral Desmophyllum cristagalli from the North Atlantic

The use of the term microspine by Balinski (1975) for a variety of structures on several taxa of spiriferides is discussed and, in part, rejected. Balinski described two distinct structures; true microspines and a papillose ornamentation resulting from external shell erosion. Evidence for a microspinose ornamentation on species of Crurithyris is presented together with models distinguishing the growth of spines in spiriferides from that in productaceans.

• Read more about Micro-ornamentation of some spiriferide brachiopods

A single specimen of Meneghiniceras lariense (Meneghini) found in the Semicelatum Subzone, Tenui-costatum Zone, of the Upper Lias of the north Yorkshire coast, is the only example of the genus found north of the Alps or outside the Tethyan area, and is stratigraphically the youngest occurrence of the genus.

• Read more about An occurrence of the Tethyan ammonite Meneghiniceras in the Upper Lias of the Yorkshire coast

Pleromic dentine is reported filling the pore-cavity spaces within the cosmine of the Early Permian rhipidistian fish Ectosteorhachis nitidus Cope (Family Osteolepidae). The pleromic tissue is only found in regions of specialized cosmine where the regular pattern of seasonal resorption and regeneration has broken down —a process that occurs in the later life history of members of this species. The functional significance of the pleromic tissue seems lo be mechanically to reinforce these regions of more permanent cosmine, with minimal loss of function in the pore-canal sensory system.

• Read more about Pleromic dentine in a Permian crossopterygian fish (Family Osteolepidae)

A new species of Corvaspis, C. arctica, is described from the Peel Sound Formation of Somerset Island, North-west Territories, Canada, where it occurs in association with Hemicyclaspis murchisoni (Egerton), an index fossil for the lowest Downtonian of Britain. C. arctica sp. nov. is considered to have been a streamlined form, with an undivided dorsal shield; it is probably related to the Cyathaspididae.

• Read more about A new species of Corvaspis (Agnatha, Heterostraci) from the Upper Silurian to Lower or Middle Devonian of the North-West Territories, Canada

Protospinax Woodward, 1919 (Kimmeridgian) is synonymous with Belemnobatis Thiolliere, 1854, and is a rhinobatoid. The paratype of P. annectans Woodward, 1919 differs fundamentally from the holotype; it is described as Squalogaleus woodwardi gen. and sp. nov. and has galeoid-like jaws which lack an otic process. Primitive rhinobatoids and squatinoids have similar pectoral fin structure and a pectoral notch, suggesting a close primitive relationship.

• Read more about The Jurassic selachian fish Protospinax Woodward

Phillipsinella fornebuensis sp. nov. and P. preclara sp. nov. are described from the Caradoc Lower Chas-mops Shale (4ba) and the Upper Chasmops Limestone (4bS1-2) respectively of the Oslo Region, Norway, together with figured but unnamed specimens from equivalent horizons and older in Sweden. Material of P. preclara sp. nov. is also figured from the highest Pusgillian of northern England. The Norwegian material provides new information on muscle-scar patterns and exoskeletal surface sculpture.

• Read more about The trilobite genus Phillipsinella from the Ordovician of Scandinavia and Great Britain

The following uppermost Ordovician-basal Silurian brachiopods of Hirnantian age from the White Head Formation at Perce, Quebec, Canada, are described and illustrated: Himantia sagittifera, Dalmanella? sp., Kinnella kielanae, Eostropheodonta siluriana, and Plectothyrella crassicosta. The occurrence is the first typical North European Hirnantian brachiopod fauna from North America to be identified at the specific level.

• Read more about Brachiopods from the Hirnantian Stage (Ordovician–Silurian) at Percé, Quebec

Sympatric species of Micraster recorded from the upper Cretaceous Chalk of England are most easily distinguished from one another by the relative height of their periprocts measured from the base of the test. The observation of Gauthier (1887) and Melville (1954) that Micraster species with a high conical aboral surface (so-called 'gibbous' forms) have a lower periproct than the associated non-gibbous forms is confirmed by numerical analysis of samples from the Santonian of Kent (M. gibbus and M. coranguinum) and the upper Campanian of Norfolk (M. stolleyi and the M.

• Read more about Distinction between sympatric species of Micraster (Echinoidea) from the English Chalk

Two melocrinitids occur in the Wenlock at Dudley. Promelocrinus anglicus Jaekel is represented by many specimens, whereas Promelocrinus sp. is only known from one partial fragment of the arms. Growth and variation have been studied in P. anglicus. Variation of number of plates in the interbrachial areas and in the ray trunks increases distally. The number of plates in a range of interbrachials is positively linked with the number of plates in adjacent ranges. However, the arm-branching parameters are mainly independent of one another.

• Read more about Promelocrinus from the Wenlock at Dudley