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Six ostracod assemblages have been recognized from the Headon-Bembridge Beds of the Hampshire Basin by the use of cluster analysis employing Jaccard and Dice Coefficients. They are thought to be salinity controlled and are comparable with Recent ostracod assemblages. Two are believed to represent a freshwater environment (0-30%o salinity), the first characterized by Candona and Cypridopsis, the second by Moenocypris. Three are believed to represent brackish environments, characterized by Cytheromorpha (3-9%o), Neocyprideis (9.0- 16.5%o), and Haplocytheridea (16.5- 35.0%o).

• Read more about Ostracod assemblages and the depositional environments of the Headon, Osborne, and Bembridge Beds (Upper Eocene) of the Hampshire Basin

Using the trophic group approach, seventeen macroinvertebrate and one trace-fossil association have been described quantitatively, using 170 bulk collections, from the Middle and Upper Oxfordian of Normandy, Dorset, Oxfordshire, and Yorkshire. Most associations are dominated by bivalves and gastropods, whilst echinoderms and brachiopods are less important. Sedimentary and biostratinomic evidence indicate that, with few exceptions, the associations are the autochthonous or parautochthonous relics of ancient communities.

• Read more about Corallian (Upper Jurassic) marine benthic associations from England and Normandy

Frenelopsis Schenk has been used to accommodate various species of fossil conifers with segmented shoots and small scale-like leaves at the nodes. As a contribution to the revision of conifers of this type, some of which probably have an affinity with Hirmeriella Horhammer, the species from the Cretaceous of Portugal are here redescribed. Four species are now recognized: three (one tentatively) are retained in Frenelopsis, while the fourth, with spirally instead of cyclically arranged leaves, is placed in Monica Watson.

• Read more about The conifers Frenelopsis and Manica in the Cretaceous of Portugal

The Zygospiridae are redefined to include 'primitive' atrypoid brachiopods with dorsally to dorsomedially directed spiralia, normally with fine ribs and a one-piece jugum dorsal to the spiralia. The Ordovician-Silurian family is divided into three: Zygospirinae, Catazyginae (new sub-fam.), and Tuvaellinae. Internal structures of Zygospira, Anazyga, Catazyga, Pentlandella, and Tuvaella are evaluated in terms of their evolutionary significance. A new genus Zygatrypa is erected.

• Read more about Zygospira and some related Ordovician and Silurian atrypoid brachiopods

Carnivorous mammals are identified on the basis of their carnassial dentition and their predatory preference for vertebrates. Jurassic pantotheres possess a dentition from which arose both carnivore and herbivore specializations. The changes towards carnivorous feeding involved emphasis on the cutting functions of the cheek teeth, with corresponding reduction of the crushing activities. A carnivorous mode of living evolved twice among the marsupials (borhyaenids in South America and some dasyurids in Australia) and twice among the placentals (Creodonta and Carnivora).

• Read more about Evolution in carnivorous mammals [Nineteenth Annual Address, delivered 17 March 1976]

Epidermal details are described from the leaf cushions of five species of Lepidophloios including one new species L. grangeri. Such epidermal information allows the species to be distinguished more accurately. Cushion variation within a species is also considered, with epidermal studies verifying the con specificity of specimens. It is suggested that young Lepidophloios cushions are of the Lepidodendron form, which subsequently enlarged to increase their photosynthetic ability

• Read more about Epidermal studies in the interpretation of Lepidophloios species

The two fissiculate blastoids, Astrocrinus tetragonus (Austin and Austin, 1843) and Hadroblastus(?) benniei (Etheridge and Carpenter, 1886), occur together in Early Carboniferous Visean (D) sediments of Scotland. Astrocrinus is a small, free-living eleutherozoic blastoid characterized by well-developed surface ornament. The nodes are interpreted as spine bases which, together with some brachioles, probably stabilized the animal on its substrate in periods of higher energy. H.(?) benniei, a stemmed blastoid formerly identified as Phaenoschisma?

• Read more about Two Carboniferous blastoids from Scotland

Re-examination of crocodilian remains previously referred to Goniopholis, from the lower Cretaceous of the Bahia basin (Brazil), shows they really belong to the genus Sarcosuchus (Mesosuchia, Pholidosauridae), formerly known from the Aptian of the Sahara. Resemblances between early Cretaceous African and South American vertebrate faunas anterior to the opening of the South Atlantic Ocean are stressed.

• Read more about The giant crocodilian Sarcosuchus in the early Cretaceous of Brazil and Niger

Four new species of Stenoscismatacea, Camerisma (Callaiapsida) alcaldei, C. (Callaiapsida) paucicostata, Cyrolexis granti, and Stenoscisma winkleri are described from the Cantabrian Mountains. The two species of Callaiapsida, from the lower and upper Bashkirian, are the oldest attributed to the subgenus, and they show transitional characters between C. (Camerisma) and typical C. (Callaiapsida); moreover, the distribution of the subgenus is now extended from the Arctic. Cyrolexis granti from the Kashirian is also the oldest species of the genus, previously known only from the Permian.

• Read more about New Carboniferous stenoscismatacean brachiopods from Oviedo and Leon, Spain

Teeth of a new scyliorhinid shark Megascyliorhinus cooperi gen. nov., sp. nov. from the London Clay are described and compared with M. miocaenicus (Antunes and Jonet) a Mio-Pliocene species from France, Portugal, and Tunisia, previously referred to Rhincodon. It is suggested that the genus Megascyliorhinus inhabited fairly deep water.

• Read more about A new Eocene shark from the London Clay of Essex