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The palaeoecology of the goniatite bed at Cowlow Nick, Castleton, Derbyshire

The Cowlow Nick Goniatite Bed is shown to be an accumulation of randomly oriented, hollow, or spar-filled goniatite shells of several species in a matrix of calcilutite. Of very limited dimensions, the bed is surrounded by algal limestones of the fore-reef fades of Upper B2 age (Lower Carboniferous). Suggestions as to the mode of accumulation are discussed and it is concluded that the bed represents a specialized drifted assemblage of floating shells which were washed gently into an inactive surge channel or submarine cave. Some comparable occurrences elsewhere in Derbyshire are noted.

Environmental causes of stunting in living and fossil marine benthonic invertebrates

The various environmental causes of stunting or dwarfing in marine benthonic invertebrates are reviewed for living species and an attempt made to apply the results to cited instances among fossils. Particular attention is devoted to possible hazards of interpretation, and the criteria for distinguishing between stunted adults and juveniles among fossils is outlined. It is argued that the principal factors involved apart from food supply are the salinity, oxygen content, turbidity, agitation, and temperature of the sea water, together with population density.

On the genus Pothocites Paterson

Specimens of cones identified as Pothocites grantonii Paterson from compressed material are described. In the light of the present findings, reasons are given for regarding Pothocites as the legitimate name for all known cones of Archaeocalamites (Asterocalamites), including those from petrified material, which have been previously described under the name Protocalamostachys Walton.

Time in stratigraphy

Recent publication of several formalized systems of stratigraphic classification and nomenclature provides an opportunity for the re-assessment of certain stratigraphic concepts.The scope and categories of stratigraphic studies are examined and related to the nature of the chronological record available in extant rocks. Lithostratigraphic data are identified as the matrix of a body of biostratigraphic evidence which serves as the basis for construction of a model time-scale using biochronological divisions.

A Lower Carboniferous fauna from Trevallyn, New South Wales

A Lower Carboniferous (Visean IId-IIIa ) fauna from Trevallyn near Gresford, N.S.W., is listed and the age of the fauna briefly discussed. The species considered in detail are: Fenestella allynensis sp. nov., Werriea australis Campbell, Eomarginifera tenuimontis sp. nov., Marginalia patersonensis sp. nov., Cleiothyri-dina australis Maxwell, Kitakamithyris triseptata (Campbell), Dielasmapicketti sp. nov.,'Camarotoechia' sp. B, Stenoscisma laevis sp. nov.,Prolecanites sp., ? Girtypecten sp., Pernopecten trevallynensis sp. nov., and Diodontop-teria delicata sp. nov.

Westphalian D megaspores from the Forest of Dean coalfield, England

A first description is given of Westphalian D dispersed megaspores in Britain. Among the seventeen species recorded five are new: Setosisporitespilatus, Lagenicula verrurugosa, L. perverrucata, L.? verrucata, L. irregularis. The species are assigned to nine genera as defined by Potonie and Kremp (1954). The genus Zonale-sporites (Ibrahim) Potonie and Kremp is redefined to include Superbisporites, Rotatisporites, and Radiatisporites as defined by Potonie and Kremp (1954). A list of additional macro-plant species from the Coal Measures concerned is also given.

Foraminifera in Holocene marsh cycles at Borth, Cardiganshire (Wales). Contribution—Cardigan Bay Research Project

The exposed Holocene deposits at Borth include two well-marked marsh cycles. The dominant foraminifera in these sediments are marsh and estuarine forms such as Jadammina macrescens, Protelphidium depressulum, Elphidium orbiculare, Elphidium excavatum, and Ammonia beccarii var. batavus. The distribution of these spscies reflects the different stages of the cycles and thus the late post-glacial history of Borth Bog.
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