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Microplankton assemblages are described for the first time from the Aptian type localilies at La Bedoule and Gargas, south-east France. A total of sixty-eight species and varieties of dinoflagellate cysts are recorded, a number of which are discussed in detail, and four new species are erected. These are Aptea securigera, Cyclonephelium tabulatum, Meiourogonyaulax psoros, and Protoellipsodinium clavulum. Microplankton distribution charts for the section studied and a summary chart of selected age-significant forms are included.

• Read more about Dinoflagellate cysts from the Aptian type sections at Gargas and La Bédoule, France

Marine ostracods from the Middle and Upper Lias are described and their lateral and vertical distribution along the strike from the Dorset to Yorkshire coasts analysed. The composition of the assemblages and the affinities and occurrence of the species are examined, and two new species are described. Ostracod diversity apparently decreased throughout the Margaritatus Zone and few ostracods have yet been found in the Spinatum Zone. However, the Toarcian transgression brought in a new ostracod fauna of Middle Jurassic aspect.

• Read more about Ostracods from the Domerian and Toarcian of England

Deposit-feeding marine benthic invertebrates ingest sediments and feed principally upon bacteria, whereas suspension-feeders feed mainly upon phytoplankton. This distinction is important because the predictability of phytoplankton is less than that of within-sediment bacteria. As a result, suspension-feeding populations fluctuate more than deposit-feeding populations.

• Read more about Trophic group and evolution in bivalve molluscs

Charred leaf fragments preserved in siltstone show excellent internal structure by SEM. The anatomy presents a high degree of xeromorphism. A number of features, including sunken stomata with paired subsidiary cells, specialized cells of digitate form underlying the upper epidermis and abundant sclereids in the mesophyll, are probably unique among ferns. The significance of the anatomy is discussed in relation to the possible habitat.

• Read more about Leaf anatomy of Weichselia based on fusainized material

A package of computer programs has been developed on the Institute of Geological Sciences' IBM 1130 computer which, after accepting and sorting data submitted on a simple input formal, draws straligraphical range and abundance diagrams to any desired scale. The range-diagrams may be of first occurrence; last occurrence; taxonomic order; any specified order including sorting within sub-groups. An ornamented lilhological plot is accurately aligned and a correctly ordered, punctuated and type-set list of fossil names may be produced from companion dictionaries.

• Read more about The production of stratigraphical range-diagrams by automatic methods

The Upper Devonian genus Keega Wray, originally described as an alga related to the crustose Corallinaceae, is reinterpreted to be the structurally modified base, here termed basal layer, of a laminar form of the stromatoporoid Stachyodes Bargatzky. Besides altering the status of Keega and its significance for the phytogeny of crustose coralline algae this conclusion also implies that Stachyodes adopted a laminar as well as the more common dendroid form and it supports the view that the primary internal structure of Stachyodes is cellular or microreticulate.

• Read more about The Devonian genus Keega (Algae) reinterpreted as a stromatoporoid basal layer

Three dentigerous bones from sandstones in the Kenilworth area are described and allocated to different genera of pelycosaurs. One of the specimens, the holotype of Oxyodon britannicus von Huene, 1908, is a sphenacodontine, but the generic name Oxyodon is preoccupied and the species is assigned to the genus Sphenacodon Marsh. The second specimen is designated as a new sphenacodontid species, Haptodus grandis; and the third is identified as belonging to the genus Ophiacodon Marsh—previously known only from North American deposits.

• Read more about Lower Permian Pelycosaurs from the English Midlands

The base of the Bradford Clay (Bathonian) at Bradford-on-Avon, Wiltshire, was a hardground. Soft lime-sand below the hardground was washed out to form crevices, the walls and the floor of which also became lithified.

• Read more about The ecology of a Middle Jurassic hardground and crevice fauna

Detailed investigations have been made of the stomata of several lepidodendroid species using cuticle preparations from compressions together with sections and peels from petrified material. The scanning electron microscope has allowed more critical observation of the compression preparations than has been previously possible. Structures are shown within the guard cells which are tentatively interpreted as the remains of lignified wall thickenings. This is the first time such structures have been shown in these plants.

• Read more about The Lepidodendroid stoma

Foraminifera indicative of the Terliary Lower e. Upper e, and Lower f ''Stages' of the East Indian Letter Classification ate recognized in the post-Eocene limestones of Christmas Island. The local ranges of Spiroclypeus globulus Nuttall (here regarded as a junior synonym of S. margaritatus), Miogypsina neodispansa (Jones and Chapman), Lepidocyclina (Eulepidina) ephippioides (J. and C.), and L. (E.) andrewsiana (J. and C.)—for all of which this small island is the type area —are determined. Five faunal assemblages are recognized, and one new species, Heterostegina barriei, described.

• Read more about Foraminiferal biostratigraphy of the Oligocene–Miocene limestones of Christmas Island (Indian Ocean)