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This paper gives a complete account of the historically important trilobite fauna of the Sholeshook Limestone; it comprises 50 species here placed in 40 genera and representing 23 families. Three new species, Harpidella (H.) lacrymosa, Platylichas noctua, and Primaspis llandowrorensis are included. Species of Liocnemis and Whittingtonia occur in laterally equivalent parts of the Slade and Redhill Mudstone Formation; the former genus is described for the first time from British strata. Proceratocephala is described for the first time from Wales.

• Read more about The Ordovician trilobite fauna of the Sholeshook Limestone Formation, South Wales

The phosphatic chalks of northern France exhibit a tripartite belemnite biostratigraphy, with Actinocamax veras Miller at their base. Gonioteuthis ex gr. quadrala in their upper portions, and G, quadrala Belemnitella praecursor Stolley at their summit. G.granulata (Blainville) is identified from isolated specimens collected from the base of the sequences; G. granulataquadrata (Stolley) is recognized within 'populations' from the summit of phosphatic chalks.

• Read more about Palaeobiology of Upper Cretaceous belemnites from the phosphatic chalk of the Anglo-Paris Basin

Spathites Kummel and Decker, 1954. a predominantly early to mid-Turonian genus common in Tethyan regions of both the Old and New Worlds, is a key genus in the early radiation of the Mammitinae (of which the Metoicoceratinae and Fallotitinae are shown to be synonyms). Spathitoides Wiedmann, I960 is a strict synonym and Jeanrogericeras Wiedmann, 1960 (of which Faltotites Wiedmann, i960 is a synonym) no more than subgenerically distinct. The genus evolved from Metoicoceras; a succession is demonstrated from S. (Jeanrogericeras) to S. (Spathites).

• Read more about Origin, evolution and systematics of the Cretaceous ammonoid Spathites

Some calymenid trilobites from the Wenlock Series of the Welsh Borderland are described and assigned to a new genus Tapinocalymene, type species T. nodulosa (Shirley 1933). An evolutionary lineage from T. volsoriforma sp. nov. (early Wenlock) through T. vulpecula sp. nov. (late Wenlock) to T. nodulosa (late Wenlock) is proposed, involving an increase in the length and area of the preglabellar furrow. Tapinocalymene was probably benthic in habit, and occurs in somewhat offshore, generally deepish water, elastics. Calymene diademata Barrande, 1846 (Wenlock, Bohemia), C.

• Read more about Evolution of the Silurian trilobite Tapinocalymene from the Wenlock of the Welsh Borderlands

A Palaeozoic chaetetid, bearing intramural spicule pseudomorphs. Chaetets (Boswellia) mortoni sp. nov.. is described from the British Dinantian. Spicules are preserved as calcite, pyrite, and silica pseudomorphs. Only silica pseudomorphs retain detail of their tylostyle form. Neomorphism locally obliterates the spicular fabric. A primary mineralogy is suggested consisting of an aragonitic calcareous skeleton, with entrapped opal 'A' spicules.

• Read more about Spicule pseudomorphs in a new Palaeozoic chaetetid, and its sclerosponge affinities

English late Jurassic (Middle Volgian) Hiatella occur in two habitats; firstly, as simple byssal nesllers on local hard substrates and, secondly, within Gastrochaenolites-typc borings penetrating hard substrates. Most Hiatella occupy borings that they did not originally construct themselves, although ancestors as well as other bivalve genera could have been responsible. The morphology of the Mesozoic Hiatella is compared briefly with modern species which occur around the British Isles and which include both boring and nestling forms.

• Read more about Hiatella—a Jurassic bivalve squatter?

The stereom of fossil crinoid ossicles preserved in an argillaceous matrix can be revealed by treating them with hydrofluoric acid. The clay filling the stereom pores is dissolved and the skeletal calcite is faithfully replaced by fluorite.

• Read more about A technique for revealing the stereom structure of fossil crinoids

Widespread use of gross dimensions and similar point-to-point measurements in biometric studies of fossils is probably due more to instrumental limitations and the influence of preceding studies than to theoretical considerations. Are such data suitable for classificatory studies which are heavily dependent on visual assessment of morphology? Theory suggests that the outlines of objects are particularly significant in visual recognition because of their high information content. They provide a parsimonious description of form.

• Read more about The value of outline processing in the biometry and systematics of fossils

All known Norwegian species of Tretaspis are described. Six are established taxa: T. ceriodes (Angelin) angelini Stormer, T. seticornis (Hisinger), T. anderssani Stormer, T. hadelandica hadelandica Stormer, T. sortita (Reed) broeggeri Stormer. and T. kiaeri Stormer. Three are new: T. hisingeri, T. askerensis. and T. latilimbus (Linnarsson) norvegicus. Most of these liixa have a broad runge of variation encompassing two or more morphs. The relative proportions of these morphs are used to distinguish T. latilimbus norvegicus and T. sortita broeggeri from their nominate subspecies.

• Read more about The trilobite Tretaspis from the upper Ordovician of the Oslo region, Norway

Reptomultisparsa tumida sp. nov. and Reptoclausa porcata sp. nov. are described respectively from the Bathonian Bradford Clay of Bradford-on-Avon and the Aalenian/Bajocian Inferior Oolite of the Cotswold Hills. The genus Reptoclausa was previously known only from the Cretaceous. Reptoclausa colonies have autozooecia located on longitudinal ridges which are separated by furrows composed of kenozooecia. This unusual arrangement of zooecia can be explained by the action of physiological growth gradients during colony life.

• Read more about Two new Jurassic Bryozoa from southern England