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Stichoporella stutterdi (Carruthers) Edwards is shown to differ from S. cylindrica (Lignier) Pia in the form of the distinctive opercula which terminated the side-branches in the reproductive stage of development; previous accounts of the difference were based on damaged examples. The opercula of S. stutterdi support the suggestion of Fily and Rioult (1976) based on S. cylindrica, as to their being formed immediately prior to cyst formation, and being shed to allow cyst-dispersal. The microstructure of the opercula in S. stutterdi is described. S.

• Read more about Taxonomy and opercular function of the Jurassic alga Stichoporella

Four new trilobite faunules from the Barr Group of the Girvan District are recorded; three new species are described—Remopleurides ateuchetos, Raymondaspis brocklochensis, and Hemiarges inghami. A new specific name, Xylabion kirkdandiensis, is proposed for a form from the Confinis Flags. The trilobite assemblages indicate inshore conditions of deposition; the Stinchar Limestone fauna at Minuntion Quarry is a good example of the shallow-water illaenid-cheirurid community. The close resemblance to certain lower Esbataottine Formation species indicates equivalence in age, probably upper Chazyan.

• Read more about Trilobites from the Ordovician Auchensoul and Stinchar limestones of the Girvan District, Strathclyde

Five freshwater ostracod assemblages, ecologically bound to environmental changes reflected by the sediments, and corresponding to the late Beestonian and early Cromerian pollen assemblage zones, are described. The ecological information recorded from the ostracods conforms to the climatic data offered by the palaeobotanical record.

• Read more about The middle Pleistocene ostracod fauna of the West Runton freshwater bed, Norfolk

The brachiopod Septirhynchia numidiensis sp. nov. is described from the Callovian (Jurassic) of southern Tunisia. Studies of the internal characters and their development reveal that only the adult forms possess the cardinal process and ventral median septum regarded as diagnostic of the genus. Inferred functional morphology suggests that these adult features represent direct or indirect adaptations to living partially buried in sediment, and their gradual development reflects a progressive change from an epifaunal to a semi-infaunal mode of life during ontogeny.

• Read more about Functional morphology and ontogenetic variation in the Callovian brachiopod Septirhynchia from Tunisia

Anaptychi (=lower jaws) and upper jaws of two specimens of Dactylioceras from the Yorkshire coast, found within their living chambers, are described and analysed. The corresponding lower and upper jaws are about equal in length and much shorter than the height of the living chambers. One of the ammonites contained numerous radular teeth between the lower and upper jaw. In addition, isolated lower and upper jaws attributed to Dactylioceras are reported from Reichenschwand (near Nurnberg, Federal Republic of Germany).

• Read more about The jaws and radula of the Jurassic ammonite Dactylioceras

A large trace fossil in the Limestone Coal Group of Arran is preserved in a deltaic, channel-fill sandstone from a cyclic sequence including coals. The trail, Diplichnites cuithensis ichnosp. nov., consists of two parallel series of closely spaced imprints, and is attributed to the giant Carboniferous myriapod Arthropleura, making this the earliest evidence for the genus. Analysis of the trail suggests the individual responsible was c. 1 m long, and had twenty-three pairs of appendages.

• Read more about A giant myriapod trail from the Namurian of Arran, Scotland

The Upper Ordovician (mid Caradoc: Soudleyan-Longvillian) clastic rocks of the south Berwyn Hills, North Wales, contain an abundant and diverse macrobenthic fauna dominated by epifaunal brachiopods. Based on studies in the south Berwyns, Shropshire, and Snowdonia, four communities are recognized and examined in terms of composition and related palaeoenvironmental parameters. It is concluded that the communities are intergrading and exhibit a close correlation with substrate and a broad correlation with depth, distance from shore, turbulence, and rates of sedimentation.

• Read more about Caradoc marine benthic communities of the south Berwyn Hills, North Wales

Reticuhgyra mirata, a miliolacean with some unusual morphological characters, is described from the Chimbu Limestone of Papua New Guinea.

• Read more about A new foraminifer from the Middle Eocene of Papua New Guinea

The Hampen Marly Formation of central England was laid down on a shallow shelf fringing the shore of the London Landmass to the east.

• Read more about The Hampen Marly and White Limestone formations: Florida-type carbonate lagoons in the Jurassic of central England

A single specimen of Aglaspis spinifer is unique in having the appendages preserved approximately in place. Re-examination has shown that the cephalic region bore four (perhaps five) pairs of appendages, and not six as Raasch (1939) claimed. The first pair was uniramous, apparently cylindrical and jointed, but cannot be confirmed as being chelate. The remaining pairs on the cephalic region were like those on the anterior half of the trunk, uniramous walking legs composed of five podomeres.

• Read more about Appendages of the arthropod Aglaspis spinifer (Upper Cambrian, Wisconsin) and their significance