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A detailed morphological study, through a sequence of nearshore to offshore sedimentary facies, of the Ordovician dalmanellid Onniella and the Silurian Isorthis, suggests that there is a positive correlation between environment and morphotype. A phenetic strategy model is proposed in which offshore dalmanellid populations are characterized by deep, rounded sulcate shells, V-shaped deep pedicle muscle fields, strong crural fossettes, strongly impressed dorsal adductor muscle fields (i.e. quadripartite), large non-restricted brachial valve sockets, and coarse costellae.

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The problems involved in the skewed reconstruction of structures of serially sectioned specimens are discussed. It is concluded that the deficiency of existing models, when applied to micromorphic specimens, lies in the fact that no consideration is given to the need to modify the x co-ordinates in skewed grids. A new, mathematically constructed, skewed model is proposed, which eliminates distortion in the x, y plane.

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Attention is drawn to a hitherto overlooked note by Portlock, dated 1837, which is of significance to the dates and type specimens of the trilobite species Celtencrinurus multisegmentatus (Portlock) and Cryptolithus latus Portlock, both of which have been assumed to have dated from Portlock's 1843 Report.

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Problems with specimen preparation and diagenesis make it uncertain whether all trilobites had a laminated cuticle. However, in those trilobites that do show laminations, the cuticles are not only heavily calcified but also lack any evidence of microfibrils or parabolic structures. A heavily calcined cuticle lacking parabolic structures is contrary to that of the typical, generalized arthropod cuticle.

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The Lower Albian Shenley Limestone occurs very locally in Bedfordshire, England. The environment of deposition is discussed and it is shown that the rich brachiopod fauna is preserved as slightly disturbed life-assemblages. Terebratulacean hinge plates are shown to consist, in general, of two parts, here called 'primary' and 'secondary' hinge plates; hinge plate terminology is revised. A calcareous structure attached to the dorsal side of the brachidium is described for the first time and named the 'sub-loop skirt'.

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Abundant coprolites and possibly gut fills of holostean fishes are irregularly distributed throughout the kaolinitic clays and muds of the Whitemud Formation (late Cretaceous) of the Willows-Readlyn district, south-central Saskatchewan. The coprolites show a variety of internal and external structures including coiling, folding, and contraction marks of primary origin; secondary features, for example surface cracking, due to diagenetic replacement by siderite and pyrite, and subsequent alteration to iron oxides.

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Stoliczkaia Neumayr, 1875, a predominantly Upper Albian genus of world-wide occurrence, is represented in the Lower Cenomanian of England and northern France by a species of the subgenus S. (Shumarinaia) Matsumoto and Inoma, 1975, and by two species referred to a new subgenus, S. (Lamnayella) Wright and Kennedy nov. This new subgenus is shown to include the previously described S. texana (Cragin), S. uddeni Bose, S. crotaloides (Stoliczka), and S. clavigera Neumayr. S. (Lamnayella) probably evolved from S.

• Read more about The ammonite Stoliczkaia from the Cenomanian of England and northern France

Earliest Permian (Asselian and early Sakmarian) ectoprocts were widespread, included many lineages of Carboniferous origin, and had a large number of cosmopolitan genera. Marked geographic differences in their generic diversity suggest that physical parameters, such as temperature, were important factors in controlling ectoproct distributions. Late Sakmarian and Artinskian ectoprocts show a number of distribution patterns, as well as the beginning of a clearly defined Tethyan fauna with a number of endemic genera.

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Morphological study of the monospecific genus Terebellaria has determined its unusual pattern of colony growth. Erect, almost cylindrical branches possessed an apical growth tip from which endozonal zooids were budded to extend the branch distally. A helico-spiral growth margin or, less commonly, a succession of annular growth margins, arose from the growth tip and progressed towards the colony base by budding exozonal zooids which were directed proximally so that their distal ends were nearer to the colony base than were their proximal ends.

• Read more about The spiral bryozoan Terebellaria from the Jurassic of southern England and Normandy

Paleofavosites asper (d'Orbigny) is redescribed on the basis of the holotype and additional material from its type area of the Welsh Borderland. The species shows considerable variation, particularly in the form and location of intercorallite pores, from colonies with pores, including a high proportion of solenia, almost exclusively located in corallite angles to those with up to 40% of pores within corallite walls. This species, the type species of Paleofavosites Twenhofel, 1914 includes variants with the structural features considered characteristic of Mesofavosites Sokolov, 1951.

• Read more about Variation in the Silurian tabulate coral Paleofavosites asper, and the status of Mesofavosites