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Vegetative specimens of the psilopsid Sawdonia ornata and sporangia of Dawsonites arcuatus are described from borehole cores of Emsian age from Oxfordshire. The material has been investigated by hydrofluoric acid maceration, examination by SEM of plant surfaces and latex replicas, and light microscopy of oxidized cuticles and polished rock surfaces. The spines of Sawdonia have become flattened in a vertical plane as a result of compression phenomena; the stomata were sunken.

• Read more about Early Devonian plant fossils from a southern England borehole

Ironstone nodules from a Middle Pennsylvanian locality near Carterville (Illinois) have yielded both fertile and sterile foliage of a new species of Scolecopteris. Permineralized specimens were studied utilizing polished surfaces and a modified liquid peel technique. Scolecopteris macrospora sp. nov. has ovate-elongate pinnules measuring 2-9 mm long and 2-5 mm wide, with a strong midvein that produces seldom-branched laterals that meet the margin at a 60° angle. Synangia are borne abaxially in a single row on each side of the midrib on pinnules with dissected margins.

• Read more about A new permineralized marattialean fern from the Pennsylvanian of Illinois

Hamulusella sedalanensis gen. et sp. nov., a Tethyan Palaeocene alga (Dasycladaceae) from Kurdistan shows an external morphology of serial conical segments known in other dasycladaceans, but has an unusual internal primary branch-structure distinguished by a short proximal extension below the stem-cell connection.

• Read more about A new dasycladacean alga from the Palaeocene of Kurdistan

Hybodontiform finspines have certain diagnostic features. The following are the most important: the longitudinal (axial) ornament is costate apically but tends to break up basally; there are posterior hook-denticles (probably secondarily fused to the spine, because abnormalities include partial non-sequence of denticle rows, also supernumerary denticles); osteodentine of the finspine outer layer is layered anteriorly, and this is interpreted in developmental terms.

• Read more about Growth and form of finspines in hybodont sharks

Memonomenos dyscriton Steen from the Autunian of Kost'alov in Czechoslovakia is a temnospondyl amphibian of the family Archegosauridae, and not an anthracosaur as previously believed. Because of its close similarity to Archegosaurus decheni it is transferred to the same genus as a distinct species, A. dyscriton comb. nov. It appears to have been an inhabitant of a large stratified perennial lake in the Krkonose-piedmont basin. Other material referred to the genus 'Memonomenos' is not generically or specifically determinate.

• Read more about A reappraisal of the early Permian amphibians Memonomenos dyscriton and Cricotillus brachydens

Olenellus (Olenettoides) armatus Peach, 1894 has been restudied and interpreted as having evolved by paedomorphosis. By comparison with olenellid ontogenies, O. (Olenellus) hamoculus, O. (Olenellus) intermedius, and O. (Olenellus) reticulatus, also from the 'Fucoid' Beds, are likewise considered to have evolved by paedomorphosis from O. (Olenellus) lapworthi. Paedomorphosis may have occurred in response to adaptation to zones of higher oxygen content, in shallower water.

• Read more about Paedomorphosis in Scottish olenellid trilobites (early Cambrian)

The distinctness of the Celtic biogeographic province in late Arenig and early Llanvirn time is confirmed by reassessment of its brachiopods from Anglesey. Of the eighteen brachiopod species in the Arenig Treiorwerth Formation, two orthaceans are placed in new monotypic genera: Treioria chaulioda sp. nov.

• Read more about Reassessment of Arenig and Llanvirn age (early Ordovician) brachiopods from Anglesey, north-west Wales

New material of Olenellus lapworthi: Peach and Horne, 1892,0. reticulatus Peach, 1894, and O. intermedius Peach, 1894, enables redescription of these forms and illustration by photographs for the first time. O. gigas Peach, 1894 is suppressed and O. hamoculus sp. nov. is erected. Graphs are used to illustrate the relationships established. The fauna represents the younger part of the Bonnia-Olenellus Zone in the Pacific Province of the Olenellid Realm.

• Read more about Olenellus (Trilobita) from the Lower Cambrian strata of north-west Scotland

The study of a new collection of thecideidine brachiopods from the Faringdon Sponge Gravels reveals the presence of two distinct forms, Bifolium faringdonense (Dav.) as interpreted by Pajaud (1970) and Neothecidella parviserrata sp. nov. It is believed that the previous confusion in the literature concerning the genus Bifolium Elliott, stems from Elliott's (1948) failure to appreciate that his proposed ontogenetic series embraced juveniles of more than one species.

• Read more about Revision of Aptian thecideidine brachiopods of the Faringdon Sponge Gravels

Re-examination of 122-4 m of the Upper Kimmeridge Clay (Jurassic), from the Freshwater Steps Stone Band up to the Portland Sand of the type section, east of Kimmeridge, Dorset, has been undertaken, and bed-by-bed ammonite collections made throughout this thickness. The ammonites include representatives of three genera belonging to two subfamilies: twenty species and two subspecies are described. The following taxa are new: Pectinatites (Pectinatites) dorsetensis, P. (P.) strahani, P. (P.) circumligatus; Pavlovia composita, P. composita waddingtoni, P.

• Read more about The ammonite faunas and stratigraphy of the upper part of the Upper Kimmeridge Clay of Dorset