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Fifty-nine species of Ostracoda are recorded and figured from the Kimmeridge Clay of Dorset, the type area of the Kimmeridgian Stage. Fifteen new species and one new subspecies are described. The classification of some Jurassic ostracod genera is critically reviewed and the stratigraphical distribution of each recorded species is given.

• Read more about The Ostracoda of the Dorset Kimmeridge Clay

Middle Jurassic (Bathonian) limestones and clays at a quarry north of Oxford have yielded faunas, some of which are life assemblages, and others which have been transported before burial.

• Read more about Palaeoecological studies in the Great Oolite at Kirtlington, Oxfordshire

Coelopleurus melitensis sp. nov. is described from the Lower Miocene of Malta. The genus has not previously been recorded from the Miocene of the Mediterranean region.

• Read more about A new species of Coelopleurus (Echinoidea) from the Miocene of Malta

Previous work by Raup on the mathematical description of coiled shells provides a foundation for the construction of three-dimensional scale models of cephalopod shells. A computer programme, based on the method of Raup, has been developed which contours planispiral surfaces of the cephalopod type. The computer output is then used to construct plastic models of these surfaces. The morphological range covered by this programme includes the entire suite of planispiral cephalopod forms. Provision is made for the simulation of both actual fossil species and hypothetical morphologies.

• Read more about Technique for scale modelling of cephalopod shells

Differences in the composition and diversity of marine invertebrates in the Tethyan and Boreal Realms of the Jurassic are outlined, and previous interpretations based on control by temperature, physical barriers, and depth of sea are discussed and rejected. Three sedimentary facies associations, termed terrigenous clastic, intermediate, and calcareous, are distinguished in the Jurassic of Europe and a correlation with faunal realms is shown to exist.

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An upper Maestrichtian assemblage of planktonic foraminifera is described from a sample of chalk dredged from Galicia Bank, a non-magnetic seamount off the west coast of Spain. The presence of post-Maestrichtian planktonic species in the sample is attributed to the burrowing of mud-feeding organisms. It is suggested that the very high percentage of planktonic individuals in the upper Maestrichtian limestone of Galicia Bank is a product of depth and proximity to an open oceanic environment during deposition.

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From a review of Jurassic, Cretaceous, Tertiary, and Recent coccolithophorid and discoaster material, it is suggested that the abrupt appearance of some complex forms, hitherto difficult to classify, may be explained by mineralization of already existing unmineralized stocks; it also seems likely that some living un-mineralized forms may have fossil mineralized ancestors. Some recent work on uncalcified Haptophyceae reveals interesting parallels with the coccolithophorids. One new family, Stephanolithiaceae, is erected, and four specific names are recorded in new combination.

• Read more about Taxonomic problems in the study of coccoliths [The Eleventh Annual Address, delivered 6 March 1968]

The study of the evolution of several brachiopod genera has enabled the early Silurian shelf sequences of the Welsh Borderland to be correlated with the type area of Llandovery, and, to some extent, with the graptolite zonal sequence. The transgression across the Borderland started at the beginning of Llandovery time, when areas in Montgomeryshire became inundated after a short break in deposition at the end of the Ashgill. The sea reached Shropshire, and possibly as far east as the Malverns and May Hill, by Middle Llandovery times.

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Excellently preserved specimens of Attenuatella convexa sp. nov. have enabled reconstruction of a unique brachial skeleton for Attenuatella. Apart from this characteristic the genus is closest to members of the Ambocoeliinae (Spiriferida) and its inclusion in this subfamily is still the most plausible supra-generic grouping. Globally, eleven species of Attenuatella are now documented and the known range of the genus is from the lower Artinskian (Aktastinian) to the Kazanian or Wordian Stage. The species Attenuatella convexa sp. nov., Attenuatella sp. A, and Attenuatella sp. cf.

• Read more about The unusual brachial skeleton of Attenuatella convexa sp. nov. (Brachiopoda)

Australirhynchia cudalensis gen. et sp. nov., family Rhynchotrematidae, is described and figured from the early Siegenian Mandagery Park Formation, New South Wales.

• Read more about Australirhynchia, a new Lower Devonian rhynchonelloid brachiopod from New South Wales