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The eyes of selected olenid species from Scandinavian concretionary shales were examined with the scanning electron microscope. Though these eyes are small, many previously unknown details were visible, including the 'peripheral zone' of Olenus wahlenbergi and other genera. Reconstructions, prepared by camera-lucida techniques, show the eye and the whole cephalon of certain species.In early olenids the visual surface was dehiscent in the adults and is preserved only in meraspids; in later genera the ocular suture became fused and the visual surface was retained.

• Read more about Morphology and evolution of the eye in Upper Cambrian Olenidae (Trilobita)

This paper discusses pollen and spores isolated from Carboniferous reproductive organs, including fructifications belonging to lycopods, cordaites, and seed ferns. Microspores of the monosaccate genus Endosporites were macerated from sporangia of a single cone. Morphological variability ranges from grains still within the tetra-hedral arrangement to solitary spores. Information is provided concerning saccus-corpus organization and exine infrastructure, ornamentation, and stages of saccus ontogeny.

• Read more about Combined transmission and scanning electron microscopy of in situ Palaeozoic spores

Inversidinium exilimurum, gen. et sp. nov., a problematical dinoflagellate recovered from the Aquia Formation (Upper Paleocene) of the Virginia-Maryland Coastal Plain, displays an atypical peridinioid outline characterized by a truncated antapex which ruptures to form a hitherto unreported type of antapical excystment apparatus; antapical archeopyles are exceedingly rare among the dinoflagellates.

• Read more about A problematical dinoflagellate from the Tertiary of Virginia and Maryland

• Read more about The application of electron microscopy to palaeontology

An imperfect humerus found in the Weald Clay (Lower Cretaceous) of Henfield, Sussex, represents the earliest British bird known, Wyleyia valdensis gen. et sp. nov. It is compared with other reptile and bird humeri from the Jurassic and Cretaceous.

• Read more about Wyleyia: a new bird humerus from the Lower Cretaceous of England

The precise nature of dichotomous branching in pyritized specimens of Clonograptus aureus sp. nov. of Tremadocian age is described and is compared with Arenigian species of Loganograptus and Goniograptus from Scandinavia. The manner whereby new branches are generated is analogous to the proximal end development of Didymogmptus minutus.

• Read more about On the mode of branching in a new species of Clonograptus

Rudolf Richter's proposals on practice in open nomenclature and on annotated synonymy lists are described and briefly criticized.

• Read more about Notes on open nomenclature and on synonymy lists

A new genus and species of echinoid, Aptilechinus caledonensis, is described from the Silurian (Llandovery) of Scotland. This species, the sixth known from the Silurian, is a flexible echinoid belonging to the family Lepido-centridae. It is unusual in having its largest spines attached to the ambulacra.

• Read more about A new Silurian echinoid genus from Scotland

Fifty-three species of dinoflagellate cysts and six species of acritarchs are reported from the upper Campanian Bearpaw Formation of southern Alberta. These include Diconodinium firmum sp. nov., Lejeunia parva sp. nov., L. ampla sp. nov., Spinidinium clavum sp. nov. and Hystrichosphaeridium dowlingii sp. nov. The Bearpaw Formation is divided into three informal assemblage zones. A parameter called the gonyaulacacean ratio is used as a possible guide to the salinity of the Bearpaw sea or to the proximity of the coastline. Three periods of open marine conditions are postulated.

• Read more about Dinoflagellate cysts and acritarchs from the Bearpaw Formation (Upper Campanian) of southern Alberta, Canada

Rubber latex casts of fossil lycopod stem impressions in fine-grained matrices may be subjected to scanning electron microscopy to reveal details of the original epidermal structure. This technique offers the potential of obtaining microscopic detail from plant impression fossils even if the cuticle is not preserved.

• Read more about Scanning electron microscopy of latex casts of fossil plant impressions