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The brachiopod Schizophoria verulamensis Cvancara, from the Lower Carboniferous of the Gresford district, New South Wales, has distinctive mantle canal patterns in small, medium, and large specimens. The different patterns are interpreted as stages in the ontogeny and are thought to result mainly from the growth and enlargement of the genitalia.Changes in the morphology of the canals in pedicle valves throughout six horizons in the Lower Carboniferous sequence show a trend, probably genetically controlled, towards the earlier maturity of the genitalia.

• Read more about Mantle canal patterns in Schizophoria (Brachiopoda) from the Lower Carboniferous of New South Wales

An examination of dissected specimens of the Eocene species Orbulinoides beckmannii (Saito 1962), formerly Porticulasphaera mexicana (Cusnman 1925), reveals certain morphological features not hitherto described. A study of the ontogeny of O. beckmannii and a comparison with the contemporaneous species Globigerapsis kugleri Belli, Loeblich and Tappan, and Globigerinatheka barri Bolli, Loeblich and Tappan, indicate that O. beckmannii is unlikely to be related to either of these species. It appears to have developed from some globorotaloid ancestor.

• Read more about Morphology and phylogeny of Orbulinoides beckmannii (Saito 1962)

A detailed study of some Upper Cretaceous calcareous nannoplankton of Zululand was undertaken, utilizing the optical as well as the electron microscope. Nine new species belonging to five genera are described as viewed in the electron microscope. These are Coccolithus cribosphaerella, Coccolithus zuluensium, Cyclolithus zulua, Discolithus cristallinus, Discolithus rhabdosphaericus, Discolithus spiralis, Maslovella africana, Maslovella blackii, and Maslovella pulchra. Using the sequential occurrence of the coccoliths through the top 800 ft.

• Read more about Upper Cretaceous coccolithophorids from Zululand, South Africa

A new species of Cassigerinella (C. eocaenica) is proposed for specimens obtained from an Eocene sample taken off Blake Plateau, Florida. The species is similar, but quite distinct from the Oligocene marker C. chipolensis (Cushman and Ponton 1932). Therefore the stratigraphical value of the overlap in ranges of C. chipolensis with Pseudohastigerina micro (Cole 1927) as indicators of basal Oligocene is not affected.

• Read more about A new Eocene Cassigerinella from Florida

A new type of delthyrial cover, stegidial plates, is described from very well-preserved specimens of Mucrospirifer mucronatus (Conrad) from the Traverse Group (Middle Devonian) of Michigan. Stegidial plates are unlike other delthyrial covers, such as deltidial plates and pseudodeltidia, because they are not integral parts of either valve: they are truly independent plates. As such, they can be compared only with the stegidium of some Upper Devonian spiriferides.

• Read more about A new type of delthyrial cover in the Devonian brachiopod Mucrospirifer

The morphology of Thecospira and Bactrynium is analysed functionally. It is inferred that the spiral brachidium of Thecospira, with its unique grooved lamellae, bore a simple spirolophe, and that the 'lobate apparatus' of ridges and grooves in Bactrynium bore a complex ptycholophe.

• Read more about The feeding mechanisms and affinities of the Triassic brachiopods Thecospira Zugmayer and Bactrynium Emmrich

A new genus of resserellid brachiopod, Visbyella, is erected based on Orthis visbyensis Lindstrom 1861 as type species. Visbyella is distinguished from both Resserella and Fascicostella by its hypercline dorsal interarea, its extroverted (dorsally facing) trilobed cardinal process, the presence of an apical plate, and by its tendency to have the median ridge in the brachial valve elevated anteriorly. Fascicostella is distinguished from both Visbyella and Resserella by its distinctly fasciculate ribbing.Dalmanella wisbyensis var. nana McLearn 1924 and Parmorthis visbyensis var.

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The position of crowns and stems in the rock indicates that Seirocrinus subangularis lived attached to floating logs in spite of its unusual size. The distribution of weight and flexibility along its stem is inverse to most other crinoids, but corresponds to the assumed habitat. A few general growth gradients seem to control this and other adaptive modifications of the crinoid stems.

• Read more about Form and function of the stem in a pseudoplanktonic crinoid (Seirocrinus)

Some larger foraminifera are recorded from various localities in the Central American region, many of them being illustrated. Additional information concerning, and new illustrations of, topotype material of some previously known forms are given. New subgenera Vlerkina and Vlerkinella (of the genus Heterostegind) are proposed; four new species and one new subspecies are described and illustrated. Certain aspects of the stratigraphy of the region are discussed, and the genus Pliolepidina is acknowledged to range down to the Late Eocene.

• Read more about Some larger foraminifera from the Tertiary of Central America

A section spanning the Visean/Namurian boundary is described from the eastern part of the Rhein-isehes Schiefergebirge, Germany. The goniatites, mostly belonging to the genus Eumorphoceras, have enabled the boundary between Upper and Lower Carboniferous strata to be positioned within 50 cm.

• Read more about A goniatite fauna from the Viséan/Namurian boundary