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A damping apparatus for damping vibrations in a vibrating system including a piston which is reciprocally movable in a hydraulic fluid filled damper chamber, piston movement in either direction of movement being resisted by fluid pressure in the damper chamber behind the piston, which resistance provides damping forces which act to oppose piston movement, the piston being connected to one component of the vibrating system and the damping chamber being connected to a second component of the vibrating system, characterised in that the fluid at at least a first side of the piston acts on a movable part which is movable in response to changing fluid pressure in the damper chamber at the first side of the piston as the piston moves, the movable member providing a relief volume for the fluid into which and from which fluid may flow from and towards the first side of the piston without passing to an opposite second side of the piston.

Recently, the monotypic ostracod genus Ankumia van Veen, 1932 was abandoned as nomen dubium by Jones (2003, p. 85) in favour of Platella Coryell & Fields, 1937 and a new combination was proposed for the type species of Ankumia, i.e. Platella bosqueti (van Veen, 1932). However, Ankumia bosqueti from the Maastrichtian of The Netherlands was introduced as an available taxon and, as documented by Jones (2003), the specific name is valid for recognizing the species in which ‘pathological individuals with retained moults’ occur. Therefore, there is no reason to treat Ankumia as nomen dubium. Yet, although there is no doubt about the cytherellid relationship of the species, two taxonomical questions still remain.(1) Do pathological individuals of cytherellids justify specific and/or generic ranking? Certainly they do not, and demonstration of a corresponding ‘normal’ species (including ‘pathological individuals’) among the associated cytherellids is wanting. On the other hand, if these pathological individuals can be proven as representing a discrete pathological genus, Ankumia remains as a valid genus to characterize the available species name bosqueti.(2) Why should Ankumia be abandoned in favour of Platella? When van den Bold (1967, pp. 306, 308) compared Coryell & Fields’ original Gatún ostracod fauna with his own collection from the Neogene Gatún Formation in the Panama Canal Zone, he recognized the type species, Platella gatunensis, as a small-sized cytherellid moult. Over the years about a dozen small- and normal-sized cytherellid species from all over the world have been assigned to Platella, ignoring the questionable taxonomic . . .

The Thanetian Stage in the type area is composed of the Thanet Formation, the Woolwich Bottom Bed and the Oldhaven Beds. The Thanet Formation at the stratotype localities in southeastern England contains calcareous nannoplankton Zones NP 6/7 and NP 8. The Woolwich Bottom Bed and Oldhaven Beds are not zonable in the type area. The marine “Bottom Bed” of the Woolwich and Reading Beds is, however, assignable to Zone NP 9 outside the type area (at Clarendon Hill in Wiltshire).

A laboratory-assembled high pressure liquid chromatograph with variable wavelength ultraviolet detector is described. The chromatography of the systemic fungicides benomyl, thiabendazole, thiophanate, related fungicides and benzimidazoles (13 compounds in all) is described using reverse phase and adsorption systems. Temperature affects reverse phase systems but not adsorption systems. Use of a variable wavelength detector increases sensitivity and selectivity. High pressure liquid chromatography (h.p.l.c.) has been applied to measurements of the solubility of benomyl and carbendazim in water and the degradation of benomyl in solution. Use of h.p.l.c. to measure benzimidazole residues awaits the development of methods of avoiding interference by substances extracted from crops and soils.

Thiabendazole is strongly adsorbed on soils, and is not readily extracted by conventional solvents. two-phase solvent system consisting of a mixture of aqueous ammonium chloride solution (pH 10), ethanol and chloroform was developed which extracted thiabendazole from a range of soils including high-organic fen peat soils and mushroom compost. Subsequent partition of the extract between organic solvents and acid or alkaline solutions provided sufficient clean-up for assay by ultraviolet or fluorescence spectroscopy, of concentrations of less than 1 mg thiabendazole kg−1 of soil. Investigation of the adsorption of thiabendazole from aqueous solution by soils indicated the importance of both soil organic and mineral matter and the adsorption of both neutral and protonated molecules.

The occurrence of ostracods in the Tethyan Ocean during early Jurassic times is reviewed with special reference to assemblage compositions in relation to contemporary geographical and oceano-graphical conditions. The Tethyan material is compared with the well-known and diverse early Jurassic assemblages from Northern and Western Europe and also with Triassic Tethyan ostracods. Particular attention is paid to the temporal and spatial distribution of (a) ornate bairdiids, (b) vallate healdiids, and (c) cytheracean species.

Publisher Summary Taxonomic interpretations of Recent ornate bairdiids are reviewed and monophyletic and polyphyletic origins for these forms discussed in the light of new material and new distributional data. Triebelina sertata Triebel, considered to include T. rectangulata Hu and T. lata Hu as junior synonyms, is recorded from Pleistocene deposits in Taiwan and from (Sub-)Recent bottom samples from the Taiwan Strait. The species is widely distributed in circum-tropical regions and its occurrence in the Mediterranean is regarded as a relict from the Tethyan history of the region. -A new large Triebelina species (T.j ellineki sp. nov.) is described from the Phillipines, where it is associated with T. amicitiae Keij. New records of T. raripila (G.W. Muller) indicate that it is an endemic Mediterranean species. The type species of Havanardia (H. havanensis Pokorny) is recorded by new material with associated adults and juveniles from Cozumel Island, off Mexico. In addition, new records of Glyptobairdia coronata (Brady) and Pterobairdia maddocksae McKenzie and Keij are presented. G. coronata is restricted to the Caribbean. P. maddocksae, from off W. Sumatra, has certainly suffered transport from shallow to deeper waters.

The extinction of the Suborder Metacopina in the early Toarcian (Early Jurassic) was a major event in the macro-evolutionary history of the Ostracoda. The disappearance of this long-ranging, essentially Palaeozoic, group coincides with a change in the composition of marine ostracod faunas from ones with residual Palaeozoic aspect in the pre-Toarcian (due to the presence of the Metacopina) to those dominated by the Cytheroidea, Cypridoidea and Platycopina, a pattern that continues to the present. The Metacopina had been present in many Palaeozoic assemblages although usually at low diversity and abundance but they were particularly successful in Triassic and Early Jurassic times, being diverse, abundant and with an apparently cosmopolitan distribution. Why did such a successful group that had survived four of the ’Big Five’ Phanerozoic extinction events (end Ordovician, Late Devonian, end-Permian, end-Triassic), succumb at this second order and apparently less significant early Toarcian event? The rapid decline and extinction of the Metacopina followed a major regressive phase in the Pliensbachian and broadly coincided with the onset of the early Toarcian Oceanic Anoxic Event (TOAE), which has been linked to global eustatic sea-level rise and is marked by a major, negative carbon isotope (δ13C ) excursion in the global carbon cycle. The nature and likely causes of the Metacopina extinction event (MEE) are reviewed in the context of new environmental data for the Toarcian, with particular reference to evidence from the Mochras Borehole (West Wales) ; the group’s survival of earlier biotic events is also discussed. The one distinct feature that sets the Toarcian extinction event apart from previous evolutionary crises is that the Metacopina never had to compete against relatively advanced ostracod, largely cytheroidean, taxa that were present during the Early Jurassic. We propose that this may have been a key factor in the demise of the Metacopina at this particular time.

Samples of Upper Bajocian and Lower Bathonian sediments from south Dorset were examined for microfossils and large numbers of holothurian sclerites were obtained together with ostracods, foraminiferids and microgastropods. Two holothurian form-species are redescribed and discussed.

The variations in litology, salinity and water depth recorded in the stratigraphy of the North Croatian Basin can be related to the high instability that affected the area at the time of Lower and Middle Miocene. The changes in the ostracod associations pointed out by the biostratigraphyic analysis performed on Slavonia area should correspond to changes in palaeoenvironments.