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The carapaces of Theriosynoecum fittoni (Mantell) from the uppermost Weald Clay (Lower Cretaceous) of four English localities have been measured. Nine growth stages were recognized and the shape and ornament of each stage recorded. Though change in shape is considerable, the tubercles are generally constant in number and relative position throughout development. A lectotype for the species is designated, figured, and described.

• Read more about The ontogeny of Theriosynoecum fittoni (Mantell)

A method of calculating the dimensions of ostracod growth stages is described and applied to the analysis of already published data referring to 26 species ranging in age from Ordovician to Recent.

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Tetrapterites visensis gen. et sp. nov. is the name given to examples of a spore-bearing structure from two Lower Carboniferous shales. A spore tetrad is enclosed by a non-cellular membrane of basic tetrahedral shape with wing-like appendages at the apices. These apical modifications (herein designated skiadions) are also found as separate entities in the assemblages and resemble saccate spores. Detailed descriptions of the Tetrapterites capsule and component parts are given and an attempt is made to explain its unusual organization.

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Thirty-eight species of dinoflagellates (including hystrichospheres) and of acritarchs of uncertain systematic position are recorded from the Cambridge Greensand; eight of these are new, and several others are recorded for the first time in Europe. Rock samples studied include six from the Gault immediately below, and five from the lowest Chalk Marl which continues above the 'greensand'. Evidence for the early Cenomanian (Varians Zone) age of the Cambridge Greensand is discussed.

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Schopfitheca boulayoides gen. et sp. nov., a new probable pteridosperm microsporangiate organ from an 'ironstone' concretion from the Mazon Creek area of Illinois is described as a pubescent, clavate-pyriform structure with large spores of the Monoletes (= Schopfipollenites) type.

• Read more about A probable pteridosperm microsporangiate fructification from the Pennsylvanian of Illinois

Biometrical and qualitative analysis of the form of the cardinal process in a sample of 123 brachial valves of Juresania nebrascensis (Owen) indicates that this feature is more variable than the size and shape of the valve proper. This relatively greater variability suggests that the form of the cardinal process has only limited value as a taxonomic criterion in the classification of this species.

• Read more about Taxonomic criteria in the classification of the Pennsylvanian productoid Juresania nebrascensis

A megaspore tetrad, Cystosporites devonicus sp. nov., is described from the Upper Devonian of Scaumenac Bay, Quebec, Canada. Cystosporites megaspores have previously been reported only from the Carboniferous, where they have been found in the lycopod seed Lepidocarpon. The occurrence of this Canadian Cystosporites shows that a level of heterospory equivalent to that reached by Lepidocarpon had already been attained by the late Devonian.

• Read more about A seed megaspore from the Devonian of Canada

The coral and brachiopod faunas of the Middle-Upper Devonian Ilfracombe Beds in the Brendon Hills, west Somerset, have been examined. The corals are restricted to two limestone horizons in the Ilfracombe Beds, the Rodhuish Limestone and the Roadwater Limestone; the brachiopods are sparse and more uniformly distributed throughout the succession. The rugose corals, Heterophrentis percevali sp. nov., Thamnophyllum caespitosum (Goldfuss), Acanthophyttum (Neostringophyllum) concavum (Walther) and Mesophyllum (Arcophylluni) sandhillense sp.

• Read more about Devonian corals and brachiopods from the Brendon Hills, west Somerset

Monograptus yukonensis sp. nov. is described from the uppermost part of the Read River Formation where it occurs with a rich brachiopod fauna. The equivalent of this zone in Thiiringia, Germany, is believed to lie in the eft or ey Stufe. The brachiopod fauna has a Gedinnian aspect.

• Read more about A new species of Monograptus from the Road River Formation, Yukon

• Read more about The new brachiopod genus Howseia from the Permian Magnesian Limestone of Durham