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An index of affinity which is related to the city block metric is described. Its values are found to be comparable with values derived from Pearson's coefficient of contingency when model sample assemblages are used. The value of the index of affinity which indicates that samples are taken from the same assemblage varies with the type of assemblage being sampled. This critical value can be calculated by using a simple formula.

• Read more about An evaluation of an index of affinity for comparing assemblages, in particular of Foraminifera

By considering the available relevant data on morphology, physiology, histology, and biochemistry of the lophophore and digestive tract of brachiopods, and by filling in gaps in the knowledge with analogies drawn from filter-feeding bivalves, a relatively detailed account of feeding processes in brachiopods is presented. It is shown that, except in the expulsion of wastes, similar feeding processes appear to occur in both the inarticulates and articulates.

• Read more about Brachiopod food and feeding processes

• Read more about Comments on 'The loop-development and the classification of terebratellacean brachiopods'

• Read more about A replacement name for Parotosaurus Jaekel (Amphibia: Labyrinthodontia)

In the lower Karroo Dwyka and Ecca Series there are widespread trace fossils which can be attributed with reasonable confidence to fish. Each trail is composed of a bilaterally symmetrical set of up to nine distinct waves. The waves in a set share a common wavelength and direction of travel, but they vary in form and amplitude. The marginal pair of waves has the lowest amplitude; this pair was apparently left by the pectoral fins. Pelvic appendages appear to have been responsible for the remaining paired wave(s).

• Read more about Fish trails from the early Permian of South Africa

A pygocephalomorph and syncarids are recorded from the Upper Pennsylvanian fresh-water vertebrate beds near Linton. Ohio. This assemblage, characteristic of the Coal Measures, is known from several other localities throughout the Carboniferous.

• Read more about Crustacean assemblage from the Pennsylvanian Linton vertebrate beds of Ohio

Two free-living coralline algae occur sublittorally in Mannin Bay, Conneraara, Eire. Locally they form 30-cm high autochthonous banks which cover areas up to 1 sq km and have a diverse associated fauna. The algae are restricted by light to depths between 1 m and 16m. Within this depth range the development of the banks is controlled by wave-induced currents and the algae are broken down to form an algal gravel which supports a poor fauna.There is variation in growth form within Ihe species and a scheme is suggested for describing morphology in free-living corallines.

• Read more about Ecological studies on two unattached coralline algae from Western Ireland

A new cryptodire turtle skull, Dorsetochelys delairi, is described from the Purbeckian of Dorset. It possesses features of both the Glyptopidae and the Baenidae, but cannot be accommodated satisfactorily in either of these two families. Early dichotomies of the cryptodires are discussed. It is concluded that the family Glyptopidae is the sister group of all other forms, and that only subsequently did the Baenidae diverge from the typical cryptodires, which include the modern forms.

• Read more about A new turtle skull from the Purbeckian of England and a note on the early dichotomies of cryptodire turtles

This paper reviews new and hitherto poorly understood trilobites from the type section of the early upper Cambrian Idamean Stage on Glenormiston Station, western Queensland. Revisions of local species of Pseudagnostus, Proceratopyge, Eugonocare, Stigmatoa, and Pagodia (Idamea) are given. Two new genera, Aplotaspis (Ceratopygidae) and Prismenaspis (Elviniidae) are established as well as the new species Pseudagnostus curtare, P. margopronus, Proceratopyge cryptica, Aplotaspis mucrora, Aphelaspis australis, Eugonocare whitehousei, E. quadrata, Prismenaspis brownensis, and P. aha.

• Read more about Upper Cambrian (Idamean) trilobites from western Queensland, Australia

Discovery of a well-preserved, fertile frond segment in Middle Pennsylvanian petrifaction material from Kansas provides the basis for description of an annulate pteropsid fructification. Numerous sporangia are attached to the abaxial surface of laminar pinnules in cither a solitary fashion or in groups of from two to six. Individual sporangia range up to 240 x 320 um and are divided into a narrow stalk and a spheroid distal region. Sporangial walls are one cell layer thick. Cells over much of the sporangium exhibit thick walls and represent a massive annulus.

• Read more about A new pteropsid fructification from the Middle Pennsylvanian of Kansas