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A brief review is given of the evolutionary relationships of generic groups in the Devonian goniatitc family Tornoceratidae (Ammonoidea) as an introduction to the description of two new genera, Falcitornocerai and Crassotomocems, from levels around the Frasnian-Famennian boundary. Species and subspecies of these genera are described from western Europe and Crassotornoceras is recorded also from North America. A detailed sequence of faunas with Falcitornoceras is described from the Montagne Noire across the Frasnian-Famennian boundary.

• Read more about New Late Devonian genera and species of tornoceratid goniatites

There are two viewpoints concerning the nature of flow across the siphuncular tube of Nautilus and other ectocochliates: (1) flow is uniform along the length of the tube; (2) flow is mainly localized in the septal necks. We tested these alternatives in specimens of N. pompilius by measuring flow rates through septal necks sealed with epoxy. We found that the septal neck, and specifically the so-called pillar zone, is not a conduit for fluid transport. Fluid entering or exiting the camerae flows uniformly through the permeable conchiolinous membranes of the connecting ring.

• Read more about Fluid transport properties of Nautilus siphuncular tube: within-camera distribution of flow rate

Two belemnite species, Youngibelus tubularis (Young and Bird) and Y. levis (Simpson), are described from one 7-6 m bituminous shale horizon in the falciferum Subzone of the Yorkshire Toarcian. Ontogenetic studies show a common identity for the two species in their initial growth stages (nepionic, neanic). Divergence in morphology occurs in late growth (gerontic stage) by the development of an epirostrum in Y. tubularis and rostral thickening in Y. levis. It is concluded that Y. tubularis and Y. levis are dimorphs of a single biological species.

• Read more about Sexual dimorphism in the belemnite Youngibelus from the Lower Jurassic of Yorkshire

Well-preserved axes of the southern hemisphere Permian lycopod Cyclodendron leslii (Seward, 1903) are described from localities in South Africa. New information includes details of the cuticle with stomata, epidermal cells, leafy vegetative axes, and fertile axes. C. leslii was an arborescent heterosporous lycopod with a restricted stratigraphic range, and it formed a small but significant part of the Glossapteris flora of South Africa.

• Read more about The Permian lycopod Cyclodendron leslii from South Africa

Floating jellyfish-like hydrozoans belonging to the Suborder Chondrophorina are a little known but distinctive group extending back to the Precambrian with sporadic occurrences in the Palaeozoic. Their absence from post -Carboniferous rocks was puzzling, considering their abundance and wide distribution today. Palaelophacmaea annulata (Yokoyama), from the lower Cretaceous (Barremian) of Japan, is reinterpreted as the first known example of a chondrophorine fossil from the Mesozoic. The species was previously considered to be a patelliform gastropod.

• Read more about The first Mesozoic chondrophorine (medusoid hydrozoan), from the Lower Cretaceous of Japan

Twenty-two species of non-heteromorph ammonites, distributed among fourteen genera, are described from the Miria Formation, Western Australia. The species Kitchinites spathi, Gunnarites raggatti, Kossmaticeras (Natalites) brunnschweileri, Neograhamites carnarvonensis, and Brahmaites (Brahmaites) kossmati, and the subspecies Pachydiscus (Pachydiscus) neubergicus dissitus and P. (P.) jacquoti australis are described as new. Pachydiscus species shared with Western Europe date the Miria Formation as Maastrichtian, consistent with its age assignment based on Foraminifera.

• Read more about Maastrichtian non-heteromorph ammonites from the Miria Formation, Western Australia

Rich microfossil assemblages have been recovered from closely spaced samples collected from the uppermost Llandovery and lowermost Wenlock strata of the Wenlock Edge area. Large numbers of acritarchs, chitinozoans, conodonts, foraminiferans, ostracods, and other microfossils occur through the sampled sequence and provide a much better basis for correlation of the base of the Wenlock Series than can currently be achieved with macrofossil groups.

• Read more about Microfossil distribution across the base of the Wenlock Series in the type area

Actinolepid material from the lower Devonian of Prince of Wales Island, Arctic Canada, described as Eskimaspis heintzi gen. et sp. nov. closely resembles Kujdanowiaspis and Heightingtonaspis, especially in the pattern of the head shield. In comparison with Baringaspis which is associated with it, it differs mainly in the short nuchal plate and the ornamentation of scattered tubercles.

• Read more about A new actinolepid arthrodire from the Lower Devonian of Arctic Canada

The reconstruction and interpretation of palaeo-community structure has been based largely on the taxonomic composition and relative abundance of the perserved species. An expanded and more precise understanding of some aspects of the palaeo-community can be deduced from information on the biomass and energy flow of its preserved components.

• Read more about Estimating biomass and energy flow of molluscs in palaeo-communities

Investigation of the microstructure of the ventral interarea of a juvenile denticulate spiriferacean assignable to Unispirifer reveals rod-like structures which, apart from a difference in size, are structurally almost identical with the tubercle cores of a recently discovered Aalenian thecideidine species Mimikonstantia sculpta Baker and Elston, 1984. The coincidence of cyrtomatodont teeth, shell resorption, and secondary fibrous shell, together with rod-like granular calcite structures ensheathed in secondary fibres, links the thecideidines with denticulate spiriferaceans.

• Read more about New evidence of a spiriferide ancestor for the Thecideidina (Brachiopoda)