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Statistical and ontogenetic studies of Taramelliceras richei (de Loriol) and Creniceras renggeri (Oppel) have shown identity in their early stages. Variation in protoconch size is consistent and small, as is the diameter of the nepionic constriction. Divergence in shell form occurs only at the onset of maturity, which in C. renggeri begins at about 8.4 mm. and in T. richei at about 18.8 mm. It is concluded that the two 'species' are a sexually dimorphic pair. The name C. renggeri has priority.

• Read more about Variation and ontogeny of some Oxfordian ammonites: Taramelliceras richei (de Loriol) and Creniceras renggeri (Oppel), from Woodham, Buckinghamshire

A species of Australosutura is described from Mississippian rocks of Oklahoma regarded as being Visean in age. It is most like the earlier-described Australian species, less like that from Argentina.

• Read more about Occurrence of Australosutura (Trilobita) in the Mississippian of Oklahoma, U.S.A.

Full descriptions are given of spores taken from the original macrofossil material of Ruffordia goepperti (Dunk.), Pelletieria valdensis Seward, and Schizaeopsis americana Berry. All three plants are of Early Cretaceous age, the first two from the Lower Wealden of England, and the last from the Patuxent Formation of the Potomac Group of Virginia, U.S.A. The use of measurements in the erection of species in the dispersed spore genus Cicatricosisporites is discussed in the light of these observations.

• Read more about Descriptions of schizaeaceous spores taken from Early Cretaceous macrofossils

The nature and validity of the Lower Devonian blastoid genus Belocrinus Munier-Chalmas from north-western France has been in doubt since its original description. A complete specimen of the type species, B. cottaldi (Munier-Chalmas) is described and illustrated. The genus Belocrinus is redefined; it is similar to, but not synonymous with, the genus Cordyloblastus Fay. The number of anal deltoids and hydrospires in Belocrinus could not be determined. The ontogenetic development of the plates of the calyx is also described.

• Read more about The Devonian blastoid Belocrinus from France

A numerical comparison of the populations of the outcrops formerly ascribed to the Ballyshannon Limestone and its lateral equivalents at Easky, Aughris, Serpent Rock, Streedagh, Kiln Port and Shalwy is presented. The localities define the limits of a subtrapezoidal area some 300 square miles in extent, in which the maximum distance between stations is 33 miles (Easky to Kiln Port) and the minimum 6-5 miles (Kiln Port to Shalwy). The four first named Sligo stations bear close similarities representing coral colonies, thickets, and even local coppices.

• Read more about Population studies in the Ballyshannon Limestone, Ballina Limestone, and Rinn Point Beds (Viséan) of N.W. Ireland

Nine species of Bolivinoides are described from the Upper Cretaceous (Santonian to Lower Maestrichtian) strata of the British Isles, and their stratigraphical ranges are recorded in relation to the classical mega-fossil zonation. Three of these species, Bolivinoides hiltermanni, B. praetaevigata, and B. sidestrandensis, are described as new and a lectotype is proposed for B. decorata (Jones). The phylogeny of various lineages of the genus Bolivinoides is discussed.

• Read more about The foraminiferal genus Bolivinoides from the Upper Cretaceous of the British Isles

Three species of Acaste, A. downingiae (Murchison), A. inflata (Salter), and A. subcaudata (Murchison); two species of Acastocephala gen. nov., A. macrops (Salter) and A. dudleyensis sp. nov.; and Acastoides constricta (Salter) are described from rocks of Wenlockian age from the West Midlands, Welsh Borderlands, and South Wales. Their relationships to later Silurian and early Devonian acastomorph genera are discussed.

• Read more about A revision of Acaste downingiae (Murchison) and related trilobites

Thirty-two species and subspecies of Ostracoda are recorded frofh the Upper Tealby Clay (Lower Barremian) at Dalby Hill, South Lincolnshire. Three species, Cytherelloidea dalbyensis, Amphicytherura bartensteini and Orthonotacythere problematica are considered new; two species are left under open nomenclature. Abundance data are given, and the ranges of the species in other British Lower Cretaceous formations are shown.

• Read more about Ostracoda from the Upper Tealby Clay (Lower Barremian) of South Lincolnshire

Specimens of Microplasma lovenianum Dybowski 1874 from the Wenlock Limestone of the Usk Inlier, Monmouthshire, are described and illustrated. This is the first record of the occurrence of Microplasma in Britain. The diagnosis of the genus is re-stated and a diagnosis of M. lovenianum is also given.

• Read more about The Silurian rugose coral Microplasma lovenianum Dybowski from Monmouthshire

Middle Devonian stratigraphy in the Roberts Mountains is briefly reviewed and Middle Devonian limestone strata below the Devils Gate Limestone are assigned to a brachiopod-rich formation, the Denay Limestone (new name). Walcott's Skenidium devonicum is made type species of a new dalmanellid genus Vallomyonia and his Cryptonellal circula is assigned to Leptathyris. The brachiopods of the Leptathyris circula zone (new name) and the Pentamerella subzone in the lower part of the Denay Limestone are described and illustrated and their palaeontologic evidence suggests an Eifelian assignment.

• Read more about Middle Devonian brachiopods from the Roberts Mountains, central Nevada