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The internal structures of two coralline algal reefs from St. Croix are described. The primary framebuilders are Lithophyllum congestion, which dominates in exposed mid-intertidal situations, and Porolithon pachydermum from the high intertidal. Secondary frameworks are constructed by one of the following corallines: Tenarea, Lithothamnium ruptile, Mesophyllum syntrophicum, Lithophyllum congestion, and Neogoniolithon sp., together with Homotrema and vermetid gastropods.

• Read more about Construction and preservation of two modern coralline algal reefs, St. Croix, Caribbean

The postcranial skeleton of the Triassic sphenodontid, Planocephalosaurus robinsonae, is described from dissociated remains recovered from the type locality at Cromhall Quarry, South Gloucestershire. A full reconstruction is outlined and its relationships within the Sphenodontidae are briefly discussed. A lower Jurassic eosuchian, Gephyrosaurus bridensis, is shown to share a number of characteristics with P. robinsonae, and Gephyrosaurus is consequently considered to be either a member of the Sphenodontidae or an offshoot from the stem Sphenodontidae.

• Read more about The postcranial skeleton of the Upper Triassic sphenodontid Planocephalosaurus robinsonae

The Middle to Late Albian Bear River Formation of south-western Wyoming includes a cyclic sequence of fine-grained sediments with numerous shell beds comprised of abundant, low diversity fresh- and brackish-water faunas. These record the initial marine transgression of the Cretaceous in this region (Skull Creek-Kiowa tectono-eustatic cycle) and are interpreted as part of an extensive embayment with limited marine influence.

• Read more about Palaeoecology of marginal marine sedimentary cycles in the Albian Bear River Formation of south-western Wyoming

Annual banding evident from epithecal increments and associated internal structural changes in phaceloid and massive Oxfordian corals show a range in growth rate from 5 to 10 mm yr-1 in branching colonies (Thecosmilia) and 1.5 to 3 mm yr-1 for massive colonies (Thamnasteria, Fungiastraea, Isastraed). High- and low-density growth bands are identified in massive colonies. The denser part of each couplet is consistently the broader, in contrast with that of most shallow-water modern corals. This is interpreted as due to high local turbidity.

• Read more about Sclerochronology and carbonate production in some Upper Jurassic reef corals

The stratigraphic distribution of eighteen groups of fossils commonly assigned to the calcareous algae reveals three major floras in shallow marine carbonate deposits of Palaeozoic age: (1) Cambrian flora, (2) Ordovician flora, (3) Carboniferous flora. The Cambrian flora appears abruptly near the Precambrian-Cambrian boundary and is dominated by cyanophytes. The Ordovician flora appears quickly during the lower and middle Ordovician and is dominated by chlorophytes, ?rhodophytes, and problematic groups.

• Read more about Principal floras of Palaeozoic marine calcareous algae

• Read more about Classification of the Echinodermata

The unusual septal surface typical of lytoceratid ammonites is described from unique Wester Australian specimens of the late Cretaceous Indopacific species Pseudophyllites indra (Forbes). Median dorsal septal recesses and inner septa combine to form a septate tunnel lying within the phragmocone; their free margin are complexly fluted like that of the septal periphery in contact with the outer shell wall. Functional analysis of the fluted septal recesses and inner septa suggest that they were not related to phragmocone strength but facilitated the attachment of adductor muscles.

• Read more about A muscle attachment proposal for septal function in Mesozoic ammonites

Dichograptid synrhabdosomes are reported for the first time. Synrhabdosomes of Didymograptus aff. simulans Elles and Wood from Arenig Fawr, North Wales and Azygograptus lapworthiNichohon from near Keswick, Lake District, are described, both from the Arenig Series (extensus Zone). Possible reconstructions of synrhabdosomes of D. aff. simulans are attempted. It is suggested that synrhabdosomes acted as mechanisms to promote rapid breeding in short-lived, highly favourable environmental conditions.

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Fisherites burmensis sp. nov., is described from the Lower-Middle Ordovician Wunbye Formation in the western part of the southern Shan State, Burma. This extends the geographic range of receptaculitids known from North America, Europe, and Australia to south-eastern Asia, where they have hitherto been poorly known.

• Read more about Ordovician receptaculitid algae from Burma

The neutralization and removal of decay products from pyritized fossil material with ethanolamine thioglycollate is described. Its use on a wide range of material is a significant improvement over previous techniques which, although satisfactory, were complex and hazardous to the preparator.

• Read more about Use of ethanolamine thioglycollate in the conservation of pyritized fossils