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Palaeoecology of a bituminous shale—the Lower Oxford Clay of central England

Quantitative palaeoecological studies, using triangular plots, rarefaction curves, trophic nuclei, trophic group composition, and Diversity Index, have allowed the definition of ten different biofacies within the Lower Oxford Clay (Upper Jurassic, Middle Callovian) of central England. Analysis of the distribution of these biofacies and seven lithofacies groups, has led to the recognition of the Lower Oxford Clay as a deepening-water sequence, in which two distinct environmental cycles are present.

Interrelationships of early terrestrial arthropods and plants

At the dawn of terrestrial life some remarkably close interrelationships between arthropods, vascular plants, and fungi existed and promoted co-evolutionary developments which, in the same or analogous forms, have since remained fundamental in the functioning of ecosystems. The fossil record and hypotheses on phylogenies are examined in terms of functional morphology. Spore-eating and disseminating arthropods existed at the same time as the spores of terrestrial plants and fungi became more diverse and obtained characters indicative of protection from and/or dissemination by arthropods.

Ostracods, land plants, and Charales from the basal Purbeck Beds of Portesham Quarry, Dorset

A thin cherty layer near the base of the Purbeck Beds in Dorset has yielded a flora of land plants (including stems of Equisetum mobergii. isolated seeds referred to Carpolilhes rubeola, C. glans, C. rhabdotus, C. cocos, C.gibbus, C. acinus, and C. westi spp.nov.,and cones of Araucarites sizerae sp. nov.)and fresh water Charales (Clavator westi sp. nov.) as well as freshwater ostracods. The discovery of Clavator westi in Lower Purbeck deposits opens up the possibility of separating the Lower Purbeck from the Middle Purbeck using the Charales.

A new Jurassic scaphopod from the Oxford Clay of Buckinghamshire

A new fossil scaphopod Prodentalium calveriensis from the middle Callovian, Coronaium Zone, of divert. Buckinghamshire, is described and assigned to the genus Prodentalium. It is suggested that this essentially Palaeozoic genus ranged into the Mesozoic and was there replaced by Fissidentalium. and that the two genera formed an evolutionary sequence.The association, with P. caltenensis, of the foraminiferan Episfomina is taken 10 indicate lhai these probably formed part of the diet of the scaphopods.

Transported algae as indicators of different marine habitats in the English Middle Jurassic

A microflora of red, green, and blue-green algae is recorded from the Middle Jurassic Great Oolite (Bathonian) White Limestone Division, near Cirencester, Gloucestershire. New genera described are Apophoretella (Myxophyceae) and Dobunniella (Chlorophyceae, Dasycladaceae). The fossils are not found where they grew: their probable original environments are discussed, and these suggest conditions like those of the present-day Great Bahama Bank.

Ecology and functional morphology of an uncinulid brachiopod from the Devonian of Spain

The orientations, with respect to the bedding planes, of 145 specimens of Uncinulus pita (Schnur. 1851) were plotted. From the results it is concluded that this species lived with its beak downwards and lhat the posterior region, in the sediment, was sealed by squamae and glottae. This interpretation is supported by the mesothyridid to permesothyridid pedicle opening. This life position would have been advantageous in helping the separation of inward and outward currents of sea-water, especially if the animal could rotate on its pedicle in response to changes in the marine flow. Geniculation.
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