On the invitation of the Norwegian Government a second International Conference met at Christiania in May, 1901, to revise and complete the proposals formulated at the Stockholm Conference in 1899 for a combined hydrographical and biological exploration of the North Sea and adjoining waters in the interests of the sea-fisheries.

The nomenclature follows André (1946). No Acarina were listed in the Plymouth Marine Fauna (Mar. Biol. Assoc., 1931), but Hydrogamasus littoralis, Rhombbgnathus pascens, R. seahami, and Halacarus basteri have since been recorded from Wembury (Colman, 1940).

We investigated the population dynamics of the spider crab Libinia ferreirae, focusing on the frequency distribution of individuals in size classes, sex ratio and the action of environmental variables (temperature, salinity, texture and organic matter content in the sediment) on reproduction and recruitment. Monthly collections were made in the Ubatuba region from January 1998 to December 2000. A total of 222 individuals were collected, including 123 juveniles (males and females), 43 adult males, 25 non-ovigerous adult females and 31 ovigerous females. Unlike most adult brachyurans, there was no significant size difference between sexes, and sexual dimorphism seems to be a varying characteristic for this crab genus. The reproductive period and recruitment were continuous with peaks that could be related to water mass dynamics and higher food availability in the Ubatuba region. In addition, our results increase knowledge about part of the life cycle of L. ferreirae, which could be useful for comparative studies.

The echiuran worm Thalassema thalassemum (Echiura: Echiuridae), is a deposit-feeder which uses its proboscis to collect sediment particles for ingestion. The proboscis is highly extensible and is used with dorsal surface downwards to skim particles from the sediment surface. Alternatively, the distal portion of the proboscis is arched over and the ventral surface of the tip is held against the sediment surface where ciliary movement facilitates particle collection. These methods are used in combination and collected material is moved back along the proboscis, the edges of which are rolled to form a closed tube. Burrows appear to be U-shaped with one predominantly inhalant and one exhalant opening. Faecal pellets are periodically ejected forming small mounds around exhalant openings and mean rates of 1·83 and 2·80 g dry wt d−1 were measured suggesting that, in sufficient densities, this species could make a significant contribution to macrofaunal bioturbation.

Although to many organisms manganese is known to be of great importance (Berkeley, 1922; Brenchley, 1927; Hopkins, 1930) its part in the economy of the sea is unknown. Some attempts were therefore made in 1934 to estimate the manganese in marine plankton using the residues from the determinations of phosphorus (Cooper, 1934; Harvey et alia, 1935). The residues from the triplicate digests from each cruise were combined and concentrated from about 200 to 70 ml. The concentrates were then examined quantitatively for manganese by the periodate method of Willard and Greathouse as described by Yoe (1928). In all cases but one the concentration of manganese was less than could be detected with certainty (Table I). In the absence of confirmatory data the figure of 5γ per litre of the diatom catch of May 15th must be regarded as suspect and attributable to chance contamination. Thus in these catches at L4 (5 miles off shore) during the spring outburst in 1934 manganese amounted to less than three parts per million million parts of water filtered, equivalent to one-thousandth or less of the phosphorus content.

The general composition and abundance of microalgae in sediment, water column and stomach contents of scallops were studied at two Euvola ziczac beds on the south-eastern inner Brazilian continental shelf. These areas, which support an extensive demersal fishery, are hydrologically dominated by Tropical and Subantarctic Waters and exhibit a summer water intrusion of South Atlantic Central Water (SACW). The same genera of benthic diatoms, mainly <30 μmm, were found on sediment and scallop stomach samples. Despite the seasonal variation of hydrographic conditions, the composition and abundance of main benthic diatoms from sediment and stomachs did not change throughout the year. On the other hand, phytoplankton from the water samples collected above the seabed (mainly pelagic diatoms >30 μm and dinoflagellates) was composed of distinct taxa and presented a high seasonal variation in abundance. The prevalence of microphytobenthos in the scallop diet suggests the importance of this community to the sustainability of this valuable demersal fishery resource.

A new species of Cerapopsis (Cerapopsis takamado) is described from the Atlantic coast of Morocco. The genus Cerapopsis, synonymized with Photis Kröyer for nearly a quarter of a century is re-established and now known to contain two species.

Sampling was carried out in the Celtic Sea in May 1987 over Great Sole and Cockburn Banks, and in June 1991 over Little Sole Bank, to study relationships between bank topography, hydrography and plankton distribution.

Over Great Sole and Cockburn Banks, there were various patterns in the hydrography and plankton which could be related to the banks, although there were no significant correlations with water depth. Away from the shelf-edge, stratification was lower over the banks. Higher water temperatures (at 5 m and 100 m depth) and increased concentrations of copepod nauplii and adults occurred on either side of Cockburn Bank. Abundance of mackerel (Scomber scombrus) eggs and larvae increased towards the shelf-edge, with lower numbers over Cockburn Bank.

Over Little Sole Bank, water column stratification was negatively correlated with water depth. However, this was strongly influenced by shelf-edge mixing, which was reflected in reduced stratification towards the shelf-edge. Background levels of chlorophyll-a also increased from on-shelf towards the shelf-edge. Copepod adults and nauplii, as well as mackerel eggs and larvae were more abundant with distance onto the shelf.

There was partial retention of four Argos tracked drift buoys on the south-east flank of Little Sole Bank. The mean displacement rate of the buoys was 1.35 km day−1 over 10 days, with a mean dispersion of 1.2 km day−1. A simple one-dimensional coupled physical–biological model showed the potential influence of banks resulting in earlier stratification and resultant spring bloom. Considerations of the delay in transfer of production from primary to secondary production and the effects of drift and diffusion, suggested it was unlikely that any influence of the banks on production would be directly related to bank topography, but there might be some regional enhancement of production.

During high-tide, the majority of Gobius cobitis exhibit a microhabitat shift, moving up to the mid-intertidal walls and cliffs, a typical blenniid habitat that is not used by this species during low-tide. Observations on feeding behaviour that showed that fish behave as an ambush predator, being capable of hunting fish of considerable size, combined with its movements to typical blenniid habitats, suggest that this species may have a predatory role as a fish predator on the rock intertidal.

Mitochondrial dehydrogenases, antioxidant enzymes, transaminases and cytochrome P450 activity have been studied from the digestive gland of Mytilus galloprovincialis, reared in a non-polluted area of the Mar Grande of Taranto (Ionian Sea, Mediterranean).

Sperm whales (Physeter macrocephalus) occur frequently in stranding records worldwide. However, none have been reported along the Pakistani coastline to date. This paper documents the first reported stranding of a sperm whale on the Pakistani coast. Ultimately, this finding is important in the planning of Pakistan's Biodiversity Action Plan and its National Conservation Strategy for marine mammals.

Mr. Bourne has been good enough to submit to me most of the interesting specimens of Echinoderms which he obtained during his short stay on board H.M.S. “Research.” Coming so soon after the important collection made by the Rev. W. S. Green in neighbouring waters and at greater depths, it will, I think, suffice for me to treat this collection as an appendix to that, and to refer for a general discussion of such points as appeared worth noting to my report in the Annals and Magazine of Natural History for December last.

In many coastal areas substrate is the limiting resource for benthic organisms. Some sessile species can be used as secondary substrate, reducing competition and increasing coexistence. In southern Chile, annual populations of Macrocystis pyrifera recruit and grow on the shells of Crepipatella fecunda. This study describes ecological interactions between the kelp and the slipper limpet over an annual cycle. The degree of kelp overgrowth was established by collecting sporophytes and through in situ submarine photography over a 10 month period (starting when kelp recruits became visible and ending when sporophytes were no longer present). Changes in the biochemical composition of the limpet tissue were also recorded by chemical analyses, to evaluate the potential effects (positive/neutral/negative) of kelp on C. fecunda nutritional condition. The results indicate that both species coexist, although kelp overgrowth may cause a decrease in carbohydrates in C. fecunda tissues, restricted to the period when the kelp forest reaches its maximum biomass. Individually, the short duration of the maximum overgrowth period and the size reached by C. fecunda females (up to 65 mm shell length) may enable rapid limpet recovery, avoiding competitive exclusion. On a population level, the M. pyrifera annual cycle generates the needed ‘break’ for C. fecunda populations, reducing the effects of kelp overgrowth. Thus, in the view of the neutral effect of kelp overgrowth, together with the positive effect of C. fecunda on M. pyrifera recruitment described somewhere else, this ecological interaction can be categorized as commensalism.

The spawning period of the nudibranch mollusc Onchidoris bilamellata (L.), although generally extending from December to May, has occasionally been reported to occur also in summer and early autumn. Preliminary data are presented here on the larval development of summer and early autumn spawnings and compared to previous studies of the larval development of ‘normal’ (winter-spring) spawnings. The possible causes and consequences of the rare summer and early autumn spawnings are discussed.

The nudibranch mollusc Onchidoris bilamellata is distributed around the British Isles, the Atlantic coast of France, Iceland, Greenland, and the coasts of North America and Japan (Thompson & Brown, 1976). It exhibits an annual life cycle with a single spawning season, generally extending from December to May in which the adults spawn repeatedly. At the end of May/June the post-spawning mortality of the adults is usually complete (Todd, 1979). Summer and early autumn spawnings have been recorded in intertidal populations only occasionally (Todd, 1979 and references therein; present study). Larval development has been studied previously on larvae hatching from eggs laid during the ‘normal’ spawning season. No information is available on the larval growth and development of summer and early autumn spawnings. In the present study two key points were addressed: the occurrence of individuals and spawn masses in the field throughout the year; and the identification of any distinctive traits of the July and September offspring.

The field observations were carried out on the south-eastern coast of Scotland (56°18′N 2°39′W) from July 1993 to August 1994. The surface sea-water temperatures were recorded from January 1993 to August 1994 in St Andrews (56°20′N 2°47′W), seven miles from the location under study (Figure 1).

The octopus fishery in the southern tip of South America is based on Enteroctopus megalocyathus. It is fished on both the Atlantic and Pacific coasts, but no study has yet investigated the genetic variability of this octopus, which is frequently collected as bycatch. The genetic identity and diversity of E. megalocyathus from specimens caught by the king crab fishery along the Beagle Channel in southern Chile was investigated using sequences of three mitochondrial (16S rRNA, COI and COIII) and one nuclear (rhodopsin) markers. Homologous sequences from other Enteroctopodidae were included to determine the genetic variability of E. megalocyathus. In addition to E. megalocyathus, genetic data allowed us to identify Muusoctopus eureka, a species also collected by the king crab fishery. Enteroctopus megalocyathus was found to be genetically similar to E. zealandicus; the genetic distances between these two species were low, 0% (16S rRNA), 0.2% (COI) and 0.6% (COIII), which was also confirmed by the phylogenetic topologies, as both species are in the same clade. Enteroctopus megalocyathus has low levels of genetic diversity, as shown by haplotype and nucleotide diversity values for the mitochondrial markers (Hd = 0.06–0.32; π = 0.0001–0.003), and null diversity for the nuclear marker. All the haplotypic networks resolved with the mtDNA markers showed shared haplotypes among E. megalocyathus, E. magnificus and E. zealandicus. The low genetic diversity of E. megalocyathus can be attributed to both the geological history of South America and the life history of the species, rather than to the king crab fishery.