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Although a few groups appear to be characterized by relative stability of size, growth gradients, whether isometric or allometric, have played an important role in the evolution of Australian monotremes and marsupials.Intra-speciflc size reduction, resulting from isometric change, has been a widespread phenomenon from Pleistocene to Recent. Its implications were not recognized by early taxonomists, whose undue emphasis on minor size differences as a criterion of speciation, and even failure to compare fossil and recent forms, have led to nomenclatorial confusion in some families.

• Read more about Growth gradients among fossil monotremes and marsupials

A new ophiuroid, Nullamphiura felli sp. nov., is described from Cenomarrian (Upper Cretaceous) strata of Bathurst Island, Northern Territory, Australia. This is the first recorded fossil occurrence of the cosmopolitan living genus Nullamphiura Fell 1962.Only one other ophiuroid, Ophiacantha (pphioglyphoida) fosteri Chapman 1934, is known to have been described from Australian Cretaceous beds.

• Read more about A new Upper Cretaceous ophiuroid from Australia

Investigation of the genus Pteromya Moore, originally founded onjexternal characters, has led to the conclusion that it should be referred to the family Ceratomyidae, which includes the genera Ceratomya and Gresslya. In addition to its type species, P. crowcombeia Moore, of the Rhaetic, it is considered that Pteromya should also include the basal Hettangian species 'Pleuromya' tatei Richardson & Tutcher, the Upper Rhaetic species 'P.' langportensis R. & T. (described as a variety of P.

• Read more about The Rhaetic–Hettangian bivalve genus Pteromya Moore

Shasticrioceras anglicum sp. nov., which seems to be the earliest known species of the genus, is described and the significance of its occurrence in the Compound Nodular Band D.I., at Speeton in east Yorkshire, is discussed in the light of current knowledge.

• Read more about A new heteromorph ammonite from the Lower Cretaceous of Yorkshire

Lower Permian material from Niederhasslich, Friedrichroda, and Odernheim in the author's collection and in the British Museum (Natural History) is reviewed and described. A new species, Branchiosaurus brachyrhynchus sp. nov., is erected for specimens from Friedrichroda; B. flagrifer Whittard is redefined. New combinations are Branchiosaurus (Micromelerpetori) credneri (Bulman and Whittard) and B. (Leptorophus) levis (Bulman).

• Read more about On growth stages in branchiosaurs

The Frodingham Ironstone is shown from the ammonite evidence to range from the top of the semicostatum Zone to the top of the obtusum Zone of the Lower Lias. The rich invertebrate fauna, which is considered from a palaeoecological viewpoint, includes traces of sediment-burrowing and shell-boring organisms which are described for the first time. Certain lamellibranchs in a pyrite-bearing bed are shown to be probably dwarfed. Data for such features as shell size, orientation, disarticulation, and wear are given and relationships bstween the shells and their sedimentary matrix described.

• Read more about Observations on the palaeoecology and ammonite sequence of the Frodingham Ironstone (Lower Jurassic)

Pentablastus supracarbonicus Sieverts-Doreck was described originally from only two specimens. The collection of over twenty additional specimens has now made possible a more detailed description, including an account of the internal structure. Optical discontinuities in the calcite have been used to detect boundaries between the component plates, and serial sections have been prepared by the new annular sawing technique at 0-35 mm. intervals. These methods have revealed several unexpected features, including an optical discontinuity between the body and the limbs of each radial plate.

• Read more about The anatomical structure and systematic position of Pentablastus (Blastoidea) from the Carboniferous of Spain

A systematic account of available Devonian ammonoids from western Canada is given and the evidence they provide concerning correlations within the Canadian Devonian is reviewed.

• Read more about Devonian goniatites and stratigraphical correlations in western Canada

Four types of primary spine and one type of secondary spine are described, and probable functions suggested for them. Fragments possibly of pedicellariae are described. Previous descriptions of a 'diffuse fasciole' are extended, and their significance is discussed.

• Read more about The spines and diffuse fascioles of the Cretaceous echinoid Echinocorys scutata Leske

The ostracod species Orthonotacythere inversa (Cornuel) is described and split into three subspecies which form an evolutionary sequence with O. diglypta Triebel. Other allied species are described from the Speeton Clay.

• Read more about The ostracod species Orthonotacythere inversa (Cornuel) and its allies in the Speeton Clay of Yorkshire