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current concerns about the population levels of the basking shark (cetorhinus maximus) in the north-east atlantic have prompted a need to understand population distribution, habitat preference and centres of abundance. in this study, spatial distribution maps derived from satellite-tag geolocations, boat surveys and public sightings data were compared. the broad distribution patterns revealed by these different methods are similar, but there are considerable differences in density distributions. surface sightings data show high densities, or ‘hotspots’ in the hebridean sea, clyde sea, irish sea and close inshore around devon and cornwall. tag geolocations, in contrast, identified two areas where individuals spent considerable time outside the distributions indicated by surveys and public sightings: the celtic sea and western approaches of the english channel. the reason for this disparity and its implications for population estimates for the species are discussed.

The Grenoble High Magnetic Field Laboratory (GHMFL) has completed the development of a 40-T Hybrid Magnet System to support research in steady, high magnetic fields. Oxford Instruments Superconducting has carried out the design, development and construction of the superconducting outsert system for the hybrid magnet. The superconducting magnet has been successfully tested in steady conditions on its own in a bucket-dewar at 2.8 K and at fields up to 7 T. Subsequently, the magnet has then been assembled in its cryostat in Grenoble in its final position. The magnet has been cooled down to 1.8 K and an additional test is being carried out. The resistive magnet is presently being assembled. A description of the system, its manufacture processes and main test results obtained so far will be presented.

Cladostephus verticillatus, a brown seaweed belonging to the genus Cladostephaceae, was collected from Nobska Point, La Jolla, California, during 1955 and air-dried. Alcoholic, aqueous, and sodium carbonate extracts have been analysed. The major carbohydrates are alginic acid, laminarin, fucoidin and mannitol. Quantitative estimations of the fucoidin and laminarin content (2% and 20% of dried weed, respectively) of Cladostephus spongiosus collected near Plymouth have also been carried out.