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The distribution of Orecopia is reviewed. Apart from a possible Famennian occurrence in Nevada, the genus as presently known is confined to the Frasnian of western North America and eastern Europe and is represented by five described species. Orecopia mccoyi and O. uchtensis are refigured and a new species, O. cotei, is erected for specimens from British Columbia and the Northwest Territories.It is suggested that the Tathlina Formation of the southern Northwest Territories may be late, rather than middle Frasnian.

• Read more about The Upper Devonian gastropod Orecopia in western Canada

Fossils distorted by tectonic strain can be reconstructed to their original shape if the strength and direction of the principal axes of strain are known. The ratio and orientation of the principal strains can be calculated by measuring the distortion in the angle between the median and transverse line in bilaterally symmetrical fossils like brachiopods and trilobites by several methods:a. They can be determined with exactitude if two such fossils are found on one bedding plane.b.

• Read more about An improved method of analysing distortion in fossils

A maxilla of Birgeria acuminata from the Rhaetic of the Bristol ChanneJ is described. Previous records of labyrinthodonts from the British Rhaetic are shown to belong to this piscine genus.

• Read more about On Birgeria acuminata and the absence of labyrinthodonts from the Rhaetic

Fourteen microstructures are recognized in stromatoporoid tissue, but not all are features of the tissue laid down by the organism and much fibrous, transversely porous, flocculent, pseudotubular, and melano-spheric tissue has developed from other microstructures during the process of preservation. Irregular specks of opaque matter less than 5 ft across are present in the tissue of most stromatoporoids but some have uniformly coloured tissue. During preservation these specks have moved, diffusing out into the galleries and concentrating into spheres.

• Read more about The microstructure of stromatoporoids

A general survey of the calcareous algae from Silurian limestones of the Welsh Border has yielded many algal remains particularly of the genus Girvanella. Nine species of this genus are here described, eight of which are new; and they are grouped according to their size and mode of growth. The Sarmenta group includes three new species, G. sarmenta, G. fragila, and G. prolixa; the Problematica group two new species, G. pusilla, G. incompta as well as G. problematica and its var. lumbricalis; the Media group with one new species G. media, and the Ramosa group two new species G. ramosa and G.

• Read more about Silurian Girvanella from the Welsh Borderland

Three enrolled trilobites are the first reported from the Permian of the Salt Range. Two are assigned to Ditomopyge fatmii sp. nov., the third to Kathwaia capitorosa gen. et sp. nov. Correlations point to a Late Permian age (late Guadalupian or early Dzhulfian) making these among the youngest trilobites known.

• Read more about Late Permian trilobites from the Salt Range, West Pakistan

The distribution of marine benthos in the Irish Sea is influenced by the nature of the substrate. The majority of epifaunal species are suspension feeders or carnivores and are associated with rocks or coarse-grained sediments. The majority of infaunal species are deposit feeders and are associated with fine-grained sediments. The relationships of the organic content of the sediment and the physical nature of the substrate to the benthos are discussed. It is argued that epifauna, and benthos living in well-sorted sands, are more likely to be transported after death than most infauna.

• Read more about Marine benthos, substrate and palaeoecology

The trilobites Robergia yukonensis sp. nov., Cryptolithoides, and Ampyxina salmoni Churkin are described from the Road River Formation. They occur above the Ashgillian (Late Upper Ordovician) graptolite zone of Dicellograptus complanatus var. ornatus and below beds containing the graptolite Climacograptus scalaris var. normalis of possible earliest Silurian age. Robergia and Cryptolithoides, although widely distributed geographically, have hitherto been reported from only Middle or presumed Middle Ordovician beds, and as a result have been considered reliable indices of that series.

• Read more about Upper Ordovician trilobites from northern Yukon

The eyes of some British Silurian Acastinae are described and analysed functionally. Techniques are given for measuring the size and spatial arrangement of the lenses of schizochroal eyes and the angular bearings of their lens-axes, from which may be inferred the angular range of vision of the whole eye and the relative visual acuity in different directions. In the post-larval ontogeny of the eye of Acaste downingiae (Salter) the lens-number increases with size but the angular extent of the visual field remains constant.

• Read more about Schizochroal eyes and vision of some Silurian acastid trilobites

From the Devonian succession in North and Central Vestspitsbergen, seven hundred rock-specimens collected by the author and over three hundred collected by previous Expeditions have been examined macro-scopically; two hundred and fifty of these were prepared for microscopic investigation. These included specimens from every Spitsbergen formation, and consisted typically of medium to fine-grained clastic sediments. Eighty-two dispersed spore species are recorded, of which forty-eight new species are systematically described.

• Read more about Lower and Middle Devonian spores of North and Central Vestspitsbergen