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Biostratigraphy of the early Lancefieldian sequence of Lancefield, Victoria, is described. Lancefieldian zonal composition and nomenclature is revised: the earliest zone, La 1, here renamed the Zone of Dictyonema scitulum and Anisograptus, is comprised of D. scitulum Harris and Keble, D1 enigma sp. nov., Anisograptus compactus sp. nov., and A. delicatulus sp. nov. A newly discovered assemblage with Psigraptus and several species of Clonograptus has been found in overlying strata and is here given the new zonal designation, La 1.5, Psigraptus and Clonograptus.

• Read more about The Tremadoc graptolite sequence of Lancefield, Victoria

A silicified trilobite fauna, consisting of eighteen taxa belonging to at least fifteen genera, is described from the limestones of the upper Lochkovian to lower Pragian Garra Formation, in the vicinity of Wellington Caves, New South Wales, Australia. Seven new species are described: Proetus (Coniproetus) irroratus, Otarion listron, Otarionella taganon, Acanthopyge (Lobopyge) australiformis, Paciphacops microps, Leonaspis wellingtonensis, and Koneprusia brikelos.

• Read more about Silicified Lower Devonian trilobites from New South Wales

Conodonts are for the first time recorded from Sumatra. Limestones near Prapat, Lake Toba, northern Sumatra have yielded conodont faunas characteristic of the Late Carnian Metapolygnathus polygnathiformis conodont zone. Limestones in the Sawahlunto area of central Sumatra have also yielded probable Late Triassic conodonts.

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Archiacoceras is shown to have the most complex connecting ring among chambered Cephalopoda. The siphuncle of A. subventricosum consists of four-layered connecting rings, radiating longitudinal lamellae, and central plates. The siphuncle of an undescribed species consists of a connecting ring composed of six layers and of actinosiphonate lamellae without central plates. All ontogenetic stages of the lamellae, from budding to maturity, are observed.

• Read more about Siphuncular structures in the Devonian nautiloid Archiacoceras from the Eifel of West Germany

The periostracum of living brachiopods is highly variable in microstructure, but the secretory regimes responsible for such differences give rise to either a strictly chronological succession built up on the surface of the vesicular cells at the tip of the outer mantle lobe, or a heterochronous succession secreted simultaneously from both sides of a slot between the vesicular cells and the lobate cells which constitute the junction of the outer and inner epithelium.

• Read more about Differentiation of the brachiopod periostracum

The ammonite family Flickiidae is a mid-Cretaceous (Albian-Cenomanian) dwarf (3 cm or less diameter) group of three genera, Flickia Pervinquiere, 1907, Ficheuria Pervinquiere, 1910, and Adkinsia Bose, 1928 to which Salaziceras Breistroffer, 1936 is here added, characterized by the evolution of an archetypal simplified suture and shell form closely homoeomorphic of the ancestral Devonian Anarcestina. Previously regarded as cryptogenic, the family is shown to be an offshoot of Neophlycticeras of the Stoliczkaiinae with simplifying suture. F.

• Read more about Origin and evolution of the Cretaceous micromorph ammonite family Flickiidae

SEM examination of well-preserved protegula of acrotretid brachiopods from the Ordovician, Silurian, and Lower and Middle Devonian of Ontario, the Lower Devonian of the Yukon Territory, and the Silurian of Oklahoma, has led to the formulation of a modified selective resorption model for the formation of protegular pits in this group.

• Read more about Formation and function of protegular pitting in some North American acrotretid brachiopods

Vascoceralid ammonites are not uncommon in the earliest mid Turonian fauna of the stratotype in Touraine, France, in marked contrast to their general scarcity elsewhere in the north-west European Cretaceous. Present are numerous Neoptychites cephalotus (Courtiller) (of which N. telinga (Stoliczka), N. xetra (Stoliczka), N. telingaeformis (Solger)), N. crassus (Solger), N. perovalis Von Koenen. and N. gourguechoni Pervinquiere are considered synonyms), rare N. xetriformis Pervinquiere, Fagesia rudra (Stoliczka), and Vascocerus sp. juv.

• Read more about Vascoceratid ammonites from the type Turonian

Palaeoecological analysis of ammonoid assemblages in the Turonian (Cretaceous) Scaphites facies of Hokkaido has yielded quantitative data on distribution, mode of occurrence, and preservation of many species. The results show that most collignoniceratids, acanthoceratids, and heteromorphs in the region are autochthonous in a broad sense; the litho- and biofacies in which these groups occur suggest that the first two lived in inshore to near-shore shallow waters, and the latter in nearshore to offshore more or less deep waters.

• Read more about Palaeoecological analysis of ammonoid assemblages in the Turonian Scaphites facies of Hokkaido, Japan

Anomalocaris canadensis Whiteaves, 1892, from the Middle Cambrian of British Columbia, is reinterpreted as an ambulatory arthropod appendage. Three further species from British Columbia, A.I whiteavesi, A. gigantea, and A. cranbrookensis are synonymized with the type. A. pennsyhanica from the Lower Cambrian of Pennsylvania is retained, but the affinities of some specimens remain equivocal and these are designated A.? cf. pennsyhanica. A.? kokomoensis and A.? emmonsi are removed from the genus.

• Read more about Anomalocaris, the largest known Cambrian arthropod