Archive

Stromatolites in the Upper Triassic (Rhaetic) of south-west Britain contain lineations within (algal) laminae which are compared to filament tufts in modern algal mats. These Triassic tuft structures were formed by the clumping of highly motile micro-organisms displaying strong phototaxis, probably oscillatoriacean cyanophytes. Although such structures are common in modern algal mats they have not previously been recognized in ancient stromatolites. Their preservation in the Triassic is due to early lithification.

• Read more about Algal tuft structures in stromatolites from the Upper Triassic of south-west England

Ecological succession on small patch reef structures can be studied by employing the concept of ecological stratification. The component corals of a patch are divided into two basic categories, the B or C horizons (or strata). The former category represents the initial colonizers (or pioneers) on a soft substrate, and the latter the subsequent colonizers. The potential exists for studying the later stages of succession by finely subdividing the C horizon.

• Read more about Ecological stratification in the Pleistocene coral reefs of the Kenya coast

Several specimens of the pteridosperm Medullosa anglica Scott are described from coal balls of Lower Pennsylvanian age from eastern Kentucky, U.S.A. These stems are remarkably similar anatomically to those originally described by Scott from the Lower Coal Measures, and represent the first critically examined material of this taxon from North America.

• Read more about The petrified pteridosperm stem Medullosa anglica from the Pennsylvanian of North America

Ten distinct types of invertebrate trace fossils have been collected from the Waterstones and Lower Keuper Marl (= Tarporley Siltstone Formation, Mercia Mudstone Group, U. Scythian-Anisian, L.-M. Triassic, Warrington et al. 1980) of north Cheshire. This ichnofauna shows elements assignable to the Scoyenia and Glossifungites-Skolithos ichnofacies contrasting with the Scoyenia ichnofacies assemblage in the underlying aeolian/fluvial 'Keuper' Sandstone (= Helsby Sandstone Formation, Sherwood Sandstone Group, Scythian, L. Triassic—Warrington et al. 1980).

• Read more about A comparison between the Triassic trace fossils of Cheshire and south Germany

Fromeophyllum climax gen. et sp. nov. is a phillipsastraeinid tetracoral from the Mount Frome Limestone near Mudgee, New South Wales, Australia, where it occurs over a stratigraphical thickness of 98 m, ranging between Dalejan (Early Devonian) and possibly Eifelian (Middle Devonian) strata. The subfamily assignment is based on a close similarity to Macgeea touti Pedder, which appears to be ancestral to F. climax. Silicified specimens show F. climax to be a polymorphic fasciculate form which undergoes up to three phases of parricidal peripheral increase. When basal structures are preserved, F.

• Read more about A new phillipsastraeinid tetracoral from the Devonian of New South Wales

The pentamerids Borealis borealis and Pentamerus oblongus are redescribed and a new subspecies B. borealis osloensis subsp. nov. is erected. Specimens from the virtually continuous Llandovery succession of the Oslo Region show a gradational evolution from B. borealis to P. oblongus, with a transition within the Idwian The occurrence of different evolutionary forms suggests a diachronous base for the limestone unit containin; these fossils in the Oslo Region.

• Read more about A reappraisal of the lower Silurian brachiopods Borealis and Pentamerus

Lewesiceras peramplum (Mantell), of which Ammonites lewesiensis Mantell is a synonym, is one of the commonest ammonites in the Turonian of Touraine, France, ranging from the early Turonian to the top of the mid-Turonian. Also present are Puzosia (Puzosia) sp. and Tragodesmoceras mauryae sp. nov.; both genera were previously unknown in the area.

• Read more about Desmoceratacean ammonites from the type Turonian

Well-preserved trilobites of Upper Llandovery age are reported from two of the three Silurian inliers in the Pentland Hills. In addition to two species of Phacopina previously described, there are some fifteen species belonging to Proetidae, Aulacopleuridae, Harpetidae, Cheiruridae, Encrinuridae, Calymenidae, Odontopleuridae, and Lichidae. In the older beds (Reservoir and Deerhope formations) trilobites are relatively rare and appear to be endemic to the Midland Valley of Scotland.

• Read more about Upper Llandovery trilobites from the Pentland Hills, Scotland

Small annulate sporangia borne abaxially on pinnules attached to Psalixochlaena cylindrica foliar members are. described from coal ball specimens collected near Burnley. The Botryopteris-like nature of these Psalixochlaena sporangia and their small spiny triangular-shaped spores as seen in polar view, indicate that the genus Psalixochlaena should now be considered a member of the Botryopteridaceae. Psalixochlaena sporangia are quite unlike those of the Botryopteris type species, B. forensis.

• Read more about A petrified fern sporangium from the British Carboniferous

Coprolitic assemblages of conodonts belonging to Idiognathoides Harris and Hollingsworth have been found in a marine black shale of Lower Westphalian age, the Gastrioceras listeri marine band. The assemblages, although coprolitic, include most of the elements one would expect to find in an Upper Carboniferous assemblage which includes platform elements closely similar to Idiognathodus Gunnell.

• Read more about Coprolitic conodont assemblages from the Lower Westphalian of North Staffordshire