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The composition, classification, and phylogeny of the Homalonotidae are discussed, and new family and subfamily diagnoses given. Plaesiacomia hughesi sp. nov. and P. vacuvertis sp. nov. from the Llanvirn of Wales and Saudi Arabia respectively, and Platycoryphe dyaulax sp. nov. from the Llandovery of Saudi Arabia, are described.

• Read more about Classification and phylogeny of homalonotid trilobites

A dinoflagellate cyst assemblage is described from the Bearpaw Formation of Montana, U.S.A. Deflandrea montanaensis sp. nov. is described. Archeopyle formation in Senegalinium tricuspis (O. Wetzel) comb. nov. is demonstrated to be of the large intercalary type, and this, together with its basic cavate morphology, allows for the recombination of the species. Also recombined are S. magnifica (Stanley). ?S. albertii (Corradini), S. boloniensis (Riegel), S. gaditanum (Riegel), ?S. kozlowskii (Gorka), S. pannuceum (Stanley), S. pentagonalis (Corradini), and 5. subquadratum (Corradini).

• Read more about Dinoflagellate cysts from the Bearpaw Formation (?Upper Campanian to Maastrichtian) of Montana

Acernaspis (Eskaspis), a new subgenus, and Podowrinella, a new genus of Phacopina.from Silurian inliers of the Midland Valley of Scotland, are here proposed. A. (Eskaspis) is restricted to the Telychian (upper Llandovery) and is referred to the subfamily Phacopinae. A. (E.) sufferta (Lament) from the M. crenulata Zone of the Pentland Hills and A. (E.) woodburnensis from the upper M. sedgwickii Zone of Girvan are described.

• Read more about Some Phacopina (Trilobita) from the Silurian of Scotland

The distribution of charophyte gyrogonites in the Headon, Osborne, and Bembridge Beds is analysed. The flora, including a new species, Nitellopsis (Tectochara) latispira, is described. It is considered that transitional forms in the genera Psilochara and Harrisichara constitute examples of evolution in Palaeogene genera. The strati-graphical importance of Sphaerochara subglobosa (Groves) Horn af Rantzien, which extends from the Upper Headon to the Lower Hamstead Beds, is discussed.

• Read more about Evolution of the charophyte floras in the Upper Eocene and Lower Oligocene of the Isle of Wight

Two new Bajocian (Middle Jurassic), microconch species belonging to the ammonite family Otoitidae, Trilobiticeras (Trilobiticeras) cricki nov. and Emileia (Otoites) douviltei nov., are described, and are paired with their probable macroconch partners, T. (Emileites) malenotatus (Buckman) and E. (E.) subcadiconica Buckman respectively. The stratigraphic distribution of the main members of the subfamily Otoitinae in southern England shows that the two new species fill an important gap in our knowledge of this subfamily. In particular T.

• Read more about Two new Bajocian microconch otoitid ammonites and their significance

Coprolites containing plant material are described from the Middle Coal Measures (Westphalian B) of Swillington, near Leeds, West Yorkshire. Other possible coprolites from the Lower Carboniferous (Calciferous Sandstone Series) of the Loch Humphrey Burn and Glenarbuck localities in the Kilpatrick Hills, Strathclyde are also recorded.

• Read more about Coprolites containing plant material from the Carboniferous of Britain

Eighty-eight species assigned or assignable to Pseudagnostus sensu lato are divided into two broad divisions based on the position of the glabellar node with respect to the anterior or anterolateral glabellar furrows and anterolateral lobes. A spectaculate division, in which the node lies to the rear of the anterior furrow and to the rear of the anterolateral lobes, is divided into nine species groups which are recognized by degree of effacement of external morphology, shield shape, border morphology, glabellar morphology, pygidial spinosity, and metamerism.

• Read more about Classification of the trilobite Pseudagnostus

Planispirally coiled protocoralla are described in Cyathaxonia tantilla (Miller) from the Lower Missis-sippian (Lower Carboniferous) of the western United States, the first record of this phenomenon in corals. Coiling is interpreted as a mode of attachment of young coralla to planktonic algae. The postulated pseudoplanktonic growth habit may be a significant factor in the widespread distribution of this species and other species of Cyathaxonia, which are generally found in rocks that record a bottom environment considered unfavourable for optimum coral growth.

• Read more about Significance of coiled protocoralla in some Mississippian horn corals

The cuticle of Asaphus raniceps Dalman has been examined with the scanning electron microscope after preparation by breaking and etching. Three main zones are denned on differences in appearance and dimensions of laminar units. Some details of the fine structure of laminar units are described. The presence of an organic framework within the cuticle is confirmed. The laminae and organization of the cuticle of this species are considered comparable to those of many extant arthropod cuticles.

• Read more about The laminae and cuticular organization of the trilobite Asaphus raniceps

Girvanella, not previously reported from rocks younger than Cretaceous, is described from the Recent. It occurs as the calcified sheath of the filamentous blue-green alga Plectonema gloeophilum Borzi in small freshwater pools on Aldabra Atoll in the Indian Ocean. The sheaths are heavily impregnated during the life of the alga by micrite grade crystals of magnesian calcite which make them hard and potentially fossilizable and which preserve the filaments as small calcareous tubes 4-10 ftm in diameter.

• Read more about Calcified Plectonema (blue-green algae), a Recent example of Girvanella from Aldabra Atoll