bluuebunny/crossref_metadata_2025 huggingface dataset:
A Comparative Study of the Chromosomes of Mytilus Edulis and Mytilus Galloprovincialis
Authors: Dixon D. R. , Flavell N.
Published: May 2009

The exact form of the taxonomic relationship between the common or blue mussel, Mytilus edulis L., and Mytilus galloprovincialis Lmk, the Mediterranean mussel, has been the subject of considerable scientific interest in recent years (for a review see Gosling, 1984). While the origins of this separation into two species rests with the original descriptions by Linnaeus and Lamarck (e.g. Soot-Ryen, 1955), interest was stimulated in recent times through the discovery by Hepper (1957) of an ‘unusual’ type of mussel at Padstow in Cornwall which, on the basis of morphological criteria, he identified as M. galloprovincialis (see also Lewis & Seed, 1969). This discovery was followed by a series of electrophoretic investigations providing evidence that the so-called ‘Padstow mussel’ exhibits genetic affinities with M. galloprovincialis from the Mediterranean (Ahmad & Beardmore, 1976; Skibinski, Ahmad & Beardmore, 1978; Skibinski, Cross & Ahmad, 1980). In her recent review paper on the systematic status of M. galloprovincialis in western Europe, Gosling (1984) considers information from morphological, cytological, immunological, electrophoretic and hybridization studies and concludes that M. galloprovincialis is a ‘form’ or ecotype of M. edulis.
Preliminary Studies on the Export of Organic Matter During Phytoplankton Blooms off La Coruña (Northwestern Spain)
Authors: Bode Antonio , Varela Manuel , Barquero Susana , Ossorio-Alvarez Ma Teresa , Gonzalez Nicolás
Published: May 2009

Sinking of particles was measured at a coastal site near La Coruña (north-western Spain) using sedimentation traps placed at the base of the euphotic zone during four short periods between March and June 1995. In addition, measurements of water column properties and particles were made at five stations. The cases studied were representative of the main oceanographic situations that occur in this area and were related to the wind-induced upwelling. Phytoplankton blooms (> 100 mg chlorophyll−a m−2) were observed on two occasions in April and June, both during favourable upwelling conditions. The two other cases were studied during low phytoplankton biomass concentrations in the water column.
Late Autumn Distribution and Seasonality of Chlorophyll-a at the Shelf-Break/Slope Region of the Armorican and Celtic Shelf
Authors: Garcia-Soto Carlos , Pingree Robin D.
Published: May 2009

Simultaneous satellite and ship measurements have characterized the structure of temperature and nitrate concentration of the Shelf-Break Front of the Armorican and Celtic Sea in late autumn (November) 1985. A chlorophyll-a distribution associated with this feature is analysed in relation to the shelf-break frontal genesis and properties, and in relation to the seasonality of in situ concentrations of chlorophyll-a at the shelf-break/slope region, adjacent shelf and adjacent ocean near ~ 47·5°N.
Population Dynamics and Secondary Production of Nereis Diversicolor in a North Norfolk Saltmarsh (UK)
Authors: Nithart Mathilde
Published: May 2009

The population dynamics of Nereis diversicolor (Annelida: Polychaeta) was studied at Stiffkey salt-marshes (north Norfolk coast). Monthly sampling from August 1992 to July 1993, on the lower salt marsh gives a mean annual density of 392 ind m−2 and a biomass of 10·26 g m−2 DW. Cohort analysis was made using ‘Bhatta’ software, allowing the growth and production estimations of the four cohorts. The production was 17·91 g m−2, giving a P:B ratio of 1·8. Nereis diversicolor population has only one recruitment in July.
Do Leptocephali of the European Eel Swim to Reach Continental Waters? Status of the Question
Authors: McCleave J.D. , Brickley P.J. , O'Brien K.M. , Kistner D.A. , Wong M.W. , Gallagher M. , Watson Stephanie M.
Published: May 2009

We examined recent arguments that leptocephali of the European eel,Anguilla anguilla, swim in an oriented manner, rather than drift, to reach the continental shelf of Europe and the Mediterranean Sea. There is a cline of increasing body length of leptocephali from south to north and from west to east from the Mid-Atlantic Ridge (30°W) to the continental shelf, which could represent migration from south-west to north-east, transport eastward at all latitudes, or increased growth rate with latitude. Evidence that this cline is a trend in age of arriving glass eels along the European coast, and that the duration of migration is less than one year, is weak. Ages reported in the literature for specimens from Morocco to The Netherlands were based on the unvalidated assumption that rings in otoliths were deposited daily. The assumption is unwarranted because of low metabolic rate and uncertainty of nutritional mode of leptocephali. If the assumption were accepted, calculated hatching dates of eels arriving at the European coast imply year-round spawning. Lengths of leptocephali in the Sargasso Sea at various times imply that eels spawn only in late winter and spring. Leptocephali contain tiny amounts of muscle, especially aerobic muscle for sustained swimming. They probably have insufficient capability to swim across the Atlantic in the less than 1–2 y reported by others.
Mass Settlement and Post-Settlement Mortality ofEpinephelus Merra(Pisces: Serranidae) On Réunion Coral Reefs
Authors: Letourneur Yves , Chabanet Pascale , Vigliola Laurent , Harmelin-Vivien Mireille
Published: May 2009

An unusual mass settlement event of the grouperEpinephelus merraoccurred on the fringing coral reefs of Reunion Island (south-western Indian Ocean) in April 1994. This major event coincided with stormy conditions associated with the new moon period. The abundance of new settlers was surveyed for 45 days following settlement on both the reef flat and the back reef area of the coral reefs of St Gilles, La Saline and St Leu. Mean densities of settlers were higher on reef flats (maximum 474 ind/20 m2at La Saline) than on back reef areas (maximum 156 ind/20 m2at La Saline). Seven weeks later, densities of settledE. merrahad drastically decreased, and did not differ with site and zone (18.5 ind/20 m2). Percentages of post-settlement mortality at that period ranged from 85 to 88% in back reef areas and from 93 to 95% on reef flats. A strong correlation between density of recruits and per capita mortality suggests density-dependent early post-settlement mortality forE. merra. The limitation of food resources and shelters, perhaps combined with an increase of diseases due to high population densities of settlers, was probably the main cause of mortality just after the mass settlement. Predation by reef fish, including cannibalism between settlers, is probably responsible for most subsequent mortality.
Dry Weights, Carbon and Nitrogen Content of Decapod Larvae from the Plankton
Authors: Lindley J.A.
Published: May 2009

The carapace lengths, dry weights, carbon content and nitrogen content of decapod larvae sorted from fresh plankton samples were measured. Regressions for the relationships between dry weight and carapace length were determined for each infraorder and for lower taxa. Regressions between carbon content, nitrogen content and C:N ratio and dry weight were calculated for the different taxa and were compared with published data on larvae reared in the laboratory.

Decapod larvae often comprise a significant component of the zooplankton of estuaries and inshore waters (Lindley et al., 1994). Lindley (1988) has presented data on the relationship between dry weight and carapace length for brachyuran larvae from the plankton. Similar data for other groups of decapods and additional data and analyses for brachyurans are presented here with data on carbon and nitrogen content. Anger & Harms (1990) described the relationships between dry weight; carbon and nitrogen content for decapod larvae reared under controlled conditions in the laboratory. The results of measurements on specimens caught in the plankton in naturally varying conditions provide a comparison with laboratory reared larvae. Harms et al. (1994) compared dry weights and biochemical data for Carcinus maenas (Brachyura) larvae reared in the laboratory with specimens from the plankton off Helgoland. Dry weights of the last two zoea stages and the megalopa larvae from the plankton were higher. The percentage carbon, nitrogen and lipid content were higher in laboratory raised larvae which were fed on Artemia nauplii than in field specimens or in laboratory reared specimens fed on phytoplankton or starved.
The larval and post-larval hinge of some families of bivalve molluscs
Authors: Le Pennec Marcel
Published: May 2009

Bivalve larvae constitute an important part of the plankton and there is a pressing need to be able to identify the various species.

The study of the development of the larval and post-larval hinge by scanning electron microscopy of 18 bivalve species shows the importance of this structure, which represents the principal character in identification of the young larval stages. This paper presents the principal distinguishing characters of the hinge (denticles, teeth and ligament) in eight families of bivalves.
The role of L-glutamate in neuromuscular transmission in some molluscs
Authors: Bone Q. , Howarth J. V.
Published: May 2009

L-glutamate is shown to have excitatory effects on muscles of the lamellibranch, Pecten and of several cephalopods. These effects are reversibly blocked by known glutamate antagonists. In Pecten intracellular electrical recording revealed a similarity between the effects of topically applied glutamate and nerve stimulation.
Metals in nereid polychaetes: the contribution of metals in the jaws to the total body burden
Authors: Bryan G. W. , Gibbs P. E.
Published: May 2009

Analyses of the jaws of Nereis virens have shown that various metals are present in detectable quantities; in order of decreasing concentration these are (with ranges (μg/g dry weight) in brackets) – zinc (10130–18360), sodium (1150–2690), magnesium (616–1080), calcium (531–1130), iron (444–1180), manganese (510–952), potassium (270–960) and copper (4–80), with also lead (8·7), cadmium (0·1) and silver (< 0·1). The most concentrated metal, zinc, is not uniformly distributed throughout the jaw, the highest level occurring in the distal tip (45740 μg/g), falling to a much lower level in the basal part (1790 μg/g). The contribution of some jaw metals to the total body burden varies according to body size: in small worms the jaw zinc accounts for over 40% of the total but in large worms it accounts for 30% or less; jaw manganese contributes over 50% of the total in small worms, dropping to about 20% with increasing size. For silver, cadmium, copper, iron and lead the jaws generally contribute less than 1% to the total body burden.
Effect of growth rate of the food alga on the growth/ingestion efficiency of a marine herbivore
Authors: Scott J. M.
Published: May 2009

The chlorophycean alga,Brachiomonas submarinavar.pulsiferaDroop, was grown in two bacteria-free chemostats, differing only in the amount of light each received. Investigations were made into the changes in biochemical composition and calorific value of the cells when they were grown at different growth rates. This information was used to help to explain changes in the growth efficiency of the rotiferBrachionus plicatilisMiiller, grown in a bacteria-free chemostat which was linked to one of the algal chemostats, the algae being supplied as the source of food.
Receptor activity in the utriculus of the sprat
Authors: Denton E. J. , Gray J. A. B.
Published: May 2009

Electrical responses were obtained from the utriculus of the sprat (Sprattus sprattusL). during stimulation by bursts of oscillatory pressures ranging in frequency from 2·5 to 880 Hz and in amplitude from 0·12 to 220 N m−2(28–93 dB above threshold). These responses had double the frequency of the stimulus and we argue that they were given by two major groups of utricular receptors, one group (decompression or d-receptors) responding to movements of the utricular floor away from the fenestra of the auditory bulla, the other group (compression or c-receptors) responding to movements of the utricular floor towards the fenestra. These groups were identified with oppositely oriented groups of utricular hair cells coupled mechanically by the rigid base on which they lie. Responses grew with increasing stimulus strength over a range of over 100 dB, the slope of the log-log relation decreasing with the larger stimuli. Above 40 Hz the delays between responses and mechanical displacements were very small and the amplitude of response depended only on the amplitude of displacement and not on frequency. Below 40 Hz the sensitivity declined more steeply with reduction of frequency than would be expected from the mechanical responses of the utricular floor. When stimulating frequencies were mixed the responses were not those expected on the hypothesis that different groups of receptors were excited by the different frequencies but those expected if all displacements of the utriculus towards or away from the fenestra from a rest position gave responses in either one or other of two major groups of receptors. The response to mixed frequency pressure waves was such that high peaks were exaggerated and information about polarity preserved. The response of the utriculus to the first cycle of a burst of sinusoidal pressure stimuli was usually larger than that to subsequent cycles.
The light-response rhythm and seasonal entrainment of the endogenous circadian locomotor rhythm ofTalitrus saltator(Crustacea: Amphipoda)
Authors: Williams John A.
Published: May 2009

Talitrus saltator, a supralittoral, sand-beach amphipod, exhibits a nocturnal, circadian, locomotor rhythm entrained by the natural photoperiod (nLD). A phase-response curve (PRC) (light pulse: 2h/400 lx) of the free-running rhythm exhibits a conventional shape; steady-state delay shifts of approximately 3·5 h occur in response to light pulses around subjective dusk, with similar advance shifts when exposed to light pulses around dawn. The seasonal variation of the overt expression of the rhythm indicates that entrainment is predominantly non-parametric, while the constant phase-angle difference between the peak of locomotor activity and dawn confirms the latter as the effective field signal for entrainment. The qualitative relationship between the time scale of the PRC and nLD, together with the absence of any seasonal variation in the periodicity of the free-running rhythm (τ), suggests that entrainment occurs through the interaction of phase shifts defined by the PRC, essentially in response to the systematically changing photoperiod.
A new species ofChthamalus(Crustacea: Cirripedia) characterized by enzyme electrophoresis and shell morphology: with a revision of other species ofChthamalusfrom the western shores of the atlantic ocean
Authors: Dando P. R. , Southward A. J.
Published: May 2009

Chthamalus proteussp. nov. is described as a distinct species based on its clear separation by starch-gel electrophoresis of enzymes. A redescription is given ofC. fragilis, a related species, which differs absolutely fromC. proteusin 3 out of 16 enzymes. Given the distinction ofC. proteusfromC. fragilisby enzyme methods, it has been possible to devise morphological criteria, involving simple measurement of the opercular valves and first maxilla, which can separate the two species in 99% of individuals. Although the morphological characters overlap slightly, the enzyme results show no evidence of hybridization. A species previously confused withC. proteus, C. bisinuatusfrom Brazil, differs considerably in morphology and is briefly redescribed.
Inorganic nitrogen metabolism in marine bacteria: Nitrogen assimilation in some marine pseudomon
Authors: Brown C. M. , Macdonald-Brown Deborah S. , Stanley S. O.
Published: May 2009

Twelve strains of psychrophilic, marine pseudomonads which grew readily on nitrate or a mixture ofamino acids, were tested for their content of the enzymes glutamine 2-oxoglutarate amino transferase (GOGAT) and glutamic dehydrogenase (GDH). All strains contained GOGAT activity when grown on nitrate and GDH when grown on amino acids. In all strains tested the synthesis of GOGAT was repressed by growth on amino acids and derepressed by growth on nitrate.
On the nutrition and metabolism of zooplankton. VIII. the grazing of Biddulphia cells by Calanus helgolandicus
Authors: Corner E. D. S. , Head R. N. , Kilvington C. C.
Published: May 2009

The rations removed by adult and stage V Calanus helgolandicus (Claus) feeding on large cells of the diatom Biddulphia sinensis Grev. were measured using an apparatus especially designed to keep the plant cells in suspension and estimated to reach a maximum of 1800 cells/animal/day at a food concentrationof 11,300 cells/1. A continual flow method was used to study feeding at very low algal concentrations and it was found that the animals still captured Biddulphia at a food level of only 270 cells/1.

The animals in the feeding experiments were used at a very low population density (6 copepods/1350 ml.) and the maximum value found for the volume of sea water swept clear – 700 ml./animal/day - was unusually high.

The maximum daily rations consumed by each animal were also high, being equivalent to 47–5 % of the body nitrogen and 46–4 % of the body phosphorus. The number of faecal pellets released by the animals increased with the size of ration captured, but the percentage of the ration lost as faecal pellets was fairly constant. In terms of dietary nitrogen the average value was 65–9% and that for dietary phosphorus 59·6%.

The percentage of the daily ration of nitrogen excreted in soluble form was 266% and that of phosphorus 41–2%, these values being significantly higher than those found using unfed animals. Nearly 90 % of the nitrogen excreted by the animals, whether feeding or unfed, was in the form of ammonia. The amounts of excreted ammonia and total soluble phosphorus increased significantly when the animals fed; but the small quantities of nitrogen released in forms other than ammonia did not change.
Volume changes shown by some littoral anomuran crustacea
Authors: Davenport John
Published: May 2009

P. platycheleswas proved to be an osmoconformer, as expected. It is assumed that the other three species are conformers.

Littoral specimens ofE. bernhardushave a similar salinity tolerance toP. platycheles,surviving from between 17 and 20·4‰ salinity to between 40·8 and 51‰ salinity if a median lethal time of above 500 h is taken to indicate survival.

The stenohaline speciesG. squamiferaandP. longicornisswell rapidly and die in 60‰ s.w. (20·4‰ salinity). Their locomotion is rapidly impaired by swelling and the integument distorted.

P. platycheles,a moderately euryhaline species, is capable of resisting swelling in 60‰ s.w., and eventually regains its original weight.

LittoralE. bernhardusshowed an unusual pattern of volume change in 60‰ xs.w. Initial swelling of 15·4‰ in the first hour was great compared with decapods likeC. maenasorP. platycheles,yet did not cause much interference with movement, and was substantially reversed in a few hours.

Increased urine production prevents swelling inP. platycheles.It is thought that increased antennary artery pressure and or a shift to a diuretic hormone balance cause increased nitration by the antennal gland.

Increased urine production is delayed until substantial swelling has occurred inE. bernhardus.

The abdomen ofE. bernhardusmakes up significantly more of the total animal weight in dilute media than in full sea water, confirming the idea that the abdomen is a ‘swelling reservoir’ protecting the rest of the animal from the mechanical effects of water inflow.

Salt loss in the urine is more important than integumental loss in both E. bernhardus and P. platycheles when they are placed in 60 % s.w.
Bioluminescence of searsid fishes
Authors: Herring Peter J.
Published: May 2009

The luminescent material emitted from the post-cleithral organ of searsid fishes is in the form of granule-packed cells. From this material a partially purified extract may be prepared which shows some of the properties to be expected from a photoprotein. The purified material luminesces on treatment with hydrogen peroxide and, specifically, ferrous iron. The properties of the luminescent system appear similar to those of material isolated from the luminous polychaeteChaetopterus.
Hydrographic and nutrient chemistry surveys in the western English channel during 1963 and 1964
Authors: Armstrong F. A. J. , Butler E. I. , Boalch G. T.
Published: May 2009

Three surveys were made in 1963 and five in 1964 in the area of the English Channel between the English and French coasts and between 3° 40' W and 5°10' W. This area had been surveyed in 1961 and 1962. Temperature and salinity were determined at o, to and 50 m and phosphate silicate and nitrate at 10 and 50 m. The results are presented graphically. Temperature and salinity were compared with Lumby's 25–year averages. The year 1963 started with unusually low temperatures and salinities higher than average. Temperature remained low in the spring, but salinity decreased. The year 1964 started with temperatures and salinities above normal, but during the rest of the year values were close to average. Nitrate in January 1964 was higher than in January 1963. Analyses of suspended matter at 12m were made for carbon, nitrogen and phosphorus on most surveys, and mean values for the whole area are given. Suspended carbon was 67 /ig C/l. in January 1963 and 51 /*g C/l. in January 1964, a significant difference. Increases in sus-pended carbon, nitrogen and phosphorus were found in spring and summer 1964.
Notes on the history and invertebrate fauna of a poikilohaline lagoon in Norfolk
Authors: Williams R. B.
Published: May 2009

The features and history of a poikilohaline lagoon near Titchwell, Norfolk, England, are described and its invertebrate fauna (recorded between 1959 and 1970) is listed. The list includes 44 species new to the lagoon since 1959 (26 species new to the Scolt Head region and four species new to Norfolk). It is considered that the fauna is of the relict type, perhaps representing what remained of a former salt-marsh fauna together with some marine species. Notes are included on the biology and geographical ranges of several species which are rare or have imperfectly known distributions in Britain. The records of five particular species are believed to represent the northern limits of these animals on the east coast in 1971, when Titchwell Lagoon was drained, destroying the fauna and flora.
Studies on egg development and larval rearing of turbot,Scophthalmus MaximusL., and Brill,Scophthalmus RhombusL., in the laboratory
Authors: Jones A.
Published: May 2009

Methods are described for rearing turbot(Scophthalmus maximusL.) and brill(Scophthalmus rhombusL.) to late larval stages; the major part of the work was done on the former species. Turbot were reared to 16–0 mm and brill to 17–0 mm in length. Rearing tanks ranged in capacity from 8 to 60 1. Turbotlarvae hatched at 2–7–3–0 mm and successful first feeding was established on rotifers(Brachionus plicatilis)at a length of 3–6–3–8 mm; larvae were transferred to a diet ofArtemianauplii at 5–6—6–0 mm. Experiments on the effect of temperature on growth and yolkabsorption rates in yolksac turbot larvae showed optimal growth efficiency at 15–0 °C. Delayed initial feeding reduced subsequent survival. Drawings of larval development of turbot and brill were made as an aid to their identification in plankton samples.
Delectona ciconiaesp. nov. (Porifera, Demospongiae) boring in the scleraxis ofCorallium rubrum
Authors: Bavestrello Giorgio , Calcinai Barbara , Sarà Michele
Published: May 2009

A new species of sponge, belonging to the genusDelectona, has been observed in the scleraxis ofCorallium rubrumfrom three Mediterranean banks (Alboran, Elba Island and Bosa Marina). The species, described here as Delecfonsciconiae, shows a spicular complement composed of spiny rhabds, very irregular in shape and size, whose derivation from amphiasters has been suggested; toxiform centrotylote oxeas; slender, irregular amphiasters and subcircular or ovoid rough discs. The taxonomic position of this species, within the Clionidae, has been discussed.
Intracellular inclusions in the nematode Tripyloides marinus from metal-enriched and cleaner estuaries in Cornwall, south-west England
Authors: Millward R. N.
Published: May 2009

Two types of electron-dense inclusions are described using transmission electron microscopy from the marine nematode Tripyloides marinus (Nematoda; BÜtshli, 1874) isolated from a metal-enriched site and a site of low metal contamination. These were classified as granular, intracellular inclusions in the intestinal syncytium, and fluid-filled vesicles along the cuticular margin of the epidermis. Energy-dispersive x-ray analysis (EDX) showed that the intestinal granules were largely comprised of P and S, with variable levels of Ca, Cu, Zn, Fe and Br, and that the epidermal vesicles contained high levels of Br and S with variable levels of Ca, Cu, Zn, Fe and P. It is suggested that intestinal granule formation may be involved in the detoxification of heavy metal sulphides and might result in a heightened ability of the species to colonize metal-enriched sediments. The function of the cuticular vesicles is unclear, but might be linked to a predatory or microbial defence mechanism (Woodin et al., 1987), or as part of a metal detoxification system.
Distribution, ecology and life-cycle of Maxmuelleria lankesteri (Echiura: Bonelliidae): a review with notes on field identification
Authors: Hughes D. J. , Ansell A. D. , Atkinson R. J. A.
Published: May 2009

This paper summarizes the available information on the distribution and biology of Maxmuelleria lankesteri. This large echiuran was described almost a century ago but its local abundance and potential importance as a bioturbator were recognized only recently. The species is widespread around the British and Irish coasts, most commonly in fine muds. A deep-burrowing, nocturnal deposit feeder, M. lankesteri is unlikely to be seen by divers, but its presence can be deduced from the form of ejecta mounds and proboscis tracks. The worms are very difficult to capture intact. Body size in a sample from Loch Sween, Argyll, was approximately normally distributed. Very small individuals are rarely found. Developing oocytes were found in the coelom over the spring and summer. Mature eggs accumulate in the gonoducts, with maximum loads found from October to December, possibly indicating a single annual spawning during the winter. Despite intensive examination of a large number of adult females, no dwarf males were found, leaving open the question of their existence. The large, yolky eggs indicate lecithotrophy or direct development. Larval stages have not been recognized. The apparent scarcity of developmental stages and of very small adults suggests that recruitment may be sparse and infrequent.
Suprabenthic crustacean fauna of a denseAmpeliscacommunity from the English Channel
Authors: Dauvin Jean-Claude , Zouhiri Souaad
Published: May 2009

Ninety-six species (97, 677individuals) were collected over the course of 6 h in five suprabenthic sledge hauls from a very denseAmpeliscafine sand community from the Bay of Morlaix (western English Channel). All the species migrated into the water column at night (98% of the specimens collected in the suprabenthos were found in the night hauls). The 23 most abundant species collected were classified into five groups based on their height within the water column, but two groups predominated: the upper suprabenthic species, abundant at 0–80–145 m above the sea-bed; and the lower suprabenthic species which were abundant only near the sea bottom (-0–1–0–75 m high). Three different patterns of nocturnal vertical migration were distinguished based on the timing of maximum swimming activity: at dusk; at the beginning of the night; or later in the night. Sexually dimorphic patterns of free-swimming behaviour was observed inAmpeliscaand some other species of Amphipoda (Bathyporeia teniupes, Metaphoxusfultoni), and Cumacea (Bodotria pulchella, Pseudocuma longicornis), with many more males than females migrating into the water column at night. Finally, the density of suprabenthic crustaceans in nocturnal hauls was amongst the highest reported from infralittoral or circalittoral suprabenthic studies on other parts of the Atlantic Ocean sampled during spring.
Breeding, recruitment and survival in a mixed intertidal population of the mudsnailsHydrobia ulvaeandH. neglecta
Authors: Barnes R. S. K.
Published: May 2009

Breeding and population statistics were assessed from February 1993 to September 1995 in a mixed population of the mudsnailsHydrobia neglectaandH. ulvaein the intertidal zone of a macrotidal bay on the Atlantic coast of Brittany, France. The biology ofH. neglectain the mixed population was identical to that found earlier for the same species when living allopatrically elsewhere in the bay, and was also that generally characterizing directly-developing species ofHydrobiathat occur in coastal lagoons. The population of the larviparousH. ulvaealso showed various features otherwise typifying lagoonal populations of this species: very high juvenile mortality, repeated failure of whole cohorts to recruit, and an age structure dominated by large and relatively old individuals. The number of eggs per capsule was normal for an intertidalH. ulvaepopulation but the number of capsules laid was remarkably low. Why both species should behave in this intertidal marine habitat as if it were lagoonal is unknown. The failure of the cohorts ofH. ulvaederiving from spring eggs in the bay may help explain why the majority of lagoonal populations of this species are dominated by old mudsnails and show negligible recruitment. There was no evidence of competitive displacement ofH. neglectabyH. ulvaein spite of received wisdom thatH. ulvaeis the competitive dominant under fully marine conditions; mortality ofH. ulvaewas more than three times that experienced byH. neglectaregardless of age of the snails.
Allozyme genetics ofMytilus edulissubjected to copper and nutritive stress
Authors: Beaumont Andy R. , Toro Jorge E.
Published: May 2009

Mytilus edulis(Mollusca: Bivalvia) collected as spat from the wild in 1990 and held in the laboratory for 18 months were divided into four groups: fed (control); starved; fed with 100 ppb added copper; and starved with 100 ppb added copper. Following >60% mortalities in the starved and copper stressed groups (but negligible mortalities in the control) surviving mussels from all four groups were genotyped at seven allozyme loci (Gpi, Lap, Pgtn, Idh, Odh, GsrandEst). Allele frequencies did not vary significantly between any of the four groups at any loci, exceptGsrwhere fed and starved groups differed. Mortalities were not genotype dependent at thePgmlocus but, in contrast, genotype frequencies at most other loci varied significantly between groups. At theGpi, Lap, GsrandOdhloci there were significant changes in proportions of heterozygotes following copper induced mortalities such that, in general, heterozygotes survived longer and homozygotes succumbed sooner. No similar pattern was evident in relation to mortalities caused by starvation; at only one locus (Idh)was there evidence of a significant effect but this was not apparently independent of the effect of copper.
The uptake of zinc from artificial sediments by Mytilus edulis
Authors: Davies N. A. , Simkiss K.
Published: May 2009

The mussel Mytilus edulis (Mollusca: Bivalvia) feeds on suspended matter filtered from the sea-water by cilia on the gill surfaces. The bivalve will clear the inhalant water of all particles >2–3 (xm including both sediment and organic matter. Marine sediments act as sinks for a variety of pollutants which may be concentrated up to 1000 fold above water levels. In a series of experiments, the uptake of zinc by M. edulis from filtered sea-water was compared with that from sea-water containing particulate matter acting as model sediments. The materials were two different ion-exchange resins, inorganic granules and hydroxyapatite particles. The accumulation of zinc from the particles was related to the amount of zinc adsorbed by the particles and to their surface properties.
Bathocyroe fosteri gen.nov., sp.nov.: a mesopelagic ctenophore observed and collected from a submersible
Authors: Madin L. P. , Harbison G. R.
Published: May 2009

Observations during four dives in the submersible ‘Alvin’ in June 1976 revealed that ctenophores were the most abundant large plankters between 400–700 m. From specimens collected with a slurp-gun device, Bathocyroe fosteri gen.nov., sp.nov., a species characterized by strong lobes, large auricles and red pigmentation of the gut, is described. Few ctenophores have been collected previously from deep water, but observations from submersibles indicate that several species occur throughout the mesopelagic zone.
The arrangement of ciliated sensory cells in Spadella (Chaetognatha)
Authors: Bone Q. , Pulsford A.
Published: May 2009

The arrangement of the ciliary sensory organs regularly arrayed on the body is re-described, and it is concluded that these are what are visible as bristles in life. On the head and tail region there are, in addition, stout single cilia, which contain multiple internal tubules, and on the head alone, there are presumed sensory cells which contain cilia within invaginations of the cell surface. Small bunches of pointed bristles occur scattered over the body surface; these are entirely distinct from the sensory cilia.
Numbers and central projections of crab second maxilla motor Neurones
Authors: Pilkington J. B. , MacFarlane D. W.
Published: May 2009

The second maxilla is innervated typically by 35 motor neurones inNectocarcinus antarcticusand about 39 inCancer novaezelandiae.Muscles are multiply innervated. Within one species variations in the number of motor neurones innervating any muscle do occur but are not common.
Distribution and reproductive biology Of Corophium insidiosum (Amphipoda) on the north-east coast of England
Authors: Sheader Martin
Published: May 2009

The distributions of Corophium insidiosum and C. bonnellii on the shores of Northumberland and Tyne and Wear suggest the former species to be common in areas of high turbidity, and the latter species in relatively clean conditions. In C. insidiosum breeding takes place throughout the year except during the months of November and December when mature females enter a ‘resting’ stage and immature females delay the onset of maturity. There are two main generations per year. Egg production is linked to a semi-lunar rhythm with peaks around the times of spring tides. Fecundity, brood mortality and feeding activity each vary seasonally.
Cirral activity and feeding in the coral-inhabiting barnacleBoscia anglicum(Cirripedia)
Authors: Anderson D. T.
Published: May 2009

In spite of a specialized shell structure and an obligate coral-inhabiting mode of life,B. anglicumretains a generalized balanoid operculum, cirri and mouthparts. These are used to capture and ingest live planktonic prey such as nauplii. Prolonged cirral extension is a preliminary to prey capture but the capture process itself involves the beating down of the prey by a series of up to six contractions and extensions of the cirri in 7–10 s. The prey is then grasped by the extended third maxillipeds (cirrus III) and drawn into the mantle cavity. An antenniform exopod of cirrus I is extended and detects the prey at the beginning of the capture sequence. The exopods of cirrus I are also used in the rejection of any unwanted particles grasped and taken in by the third maxillipeds.
The effects of simulated estuarine mantle cavity conditions upon the activity of the frontal gill cilia ofMytilus edulis
Authors: Davenport John , Fletcher John S.
Published: May 2009

The shell closure mechanism ofMytilus edulisprotects the frontal ciliary mechanism against irreversible damage by low environmental salinity levels. Previous experiments had shown that the mantle fluid of mussels exposed to fluctuating salinity regimes was held at a concentration corresponding to about 60% s.w. (20·1‰S) during the period of shell valve closure (Shumway, 1977), while the oxygen tension of the mantle cavity fell rapidly after shell valve closure to 15 mmHg and thereafter remained relatively constant until the valves reopened (Bettison & Davenport, in preparation). These conditions of salinity and oxygen tension were applied to experimental preparations and their ciliary activity assessed. The salinity conditions alone depressed activity by 39·5%. The conditions of oxygen tension alone also produced a depression of 39·5% but there were signs of recovery during the period of simulated shell valve closure. When both salinity and oxygen tension conditions were applied simultaneously a more profound depression of 64·4% was produced by the interacting factors. Exposure of preparations to salinity levels corresponding to the external environment (‘no closure’ simulation) irretrievably damaged the frontal ciliary mechanism on the first exposure to low salinity.
The cephalopod statolithan-introduction to its form
Authors: Clarke Malcolm R.
Published: May 2009

Terms, dimensions and ratios for statolith description are defined. The form of the calcareousstatoliths in the Teuthoidea, Sepiodea and Octopoda is described by reference to Loligo forbesi, Sepia officinalis and Eledone cirrosa. While statoliths change in form and size during the growth of a cephalopod, the adult form is often characteristic for a species, despite some variation. Description of statoliths is important in studies of the fossil remains of cephalopods lacking calcareous shells, and will probably become important in the taxonomy of living species, in food analysis of cephalopod predators and in the study of deep sea deposits.
A new species ofLamellisabella(Pogonophora) from the north Atlantic
Authors: Southward Eve C.
Published: May 2009

The first species ofLamellisabellato be described from the Atlantic Ocean has rows of small teeth on the tentacles. It occurs at about 4000 m depth in the Bay of Biscay, and its range probably extends along the continental rise at least as far south as the Gulf of Guinea.
Chemical Stimuli as a factor in feeding and intraspecific behaviour of Herring Larvae
Authors: Dempsey C. H.
Published: May 2009

On hatching, larvae of herring, Clupea harengus L., showed increased activity to washings and extracts of the nauplii of Balanus balanoides and to glycine and proline whichare major constituents of the free amino acid pool of Balanus. Older larvae, which were fed on the nauplii of Anemia salina, showed a response to extracts, but not to washings, of this prey; they also responded to six amino acids. The active constituents of prey extracts were found to be dialysable. Surgical section showed the olfactory system was responsible for behavioural responses in herring larvae of 21 mm (total length) to extracts of Anemiasalina. At all stages of larval life, herring showed increased activity to washings of other herring larvae. Juvenile herring showed a preference for a part of a tank containing water in which other juvenile herring had been held.
Arsenic in U.K. estuarine sediments and its availability to benthic organisms
Authors: Langston W. J.
Published: May 2009

Arsenic concentrations in estuarine sediments from England and Wales range over three orders of magnitude. The highest concentrations, up to 2500 μg/g, occur in the sediments of estuaries in south west England associated with past or present metalliferous mining activity. Strong correlations exist between arsenic and iron in 1 N-HC1 extracts of different estuarine sediments. The As/Fe ratio in those estuaries not contaminated with mine wastes is 11 × 10−4, increasing to 190 × 10—4 in metalliferous sediments.
Studies on the digestive cycle of the shore crab Carcinus maenas (L.) with special reference to the b cells in the hepatopancreas
Authors: Hopkin S. P. , Nott J. A.
Published: May 2009

Aspects of the digestive cycle of Carcinus maenas have been studied by transmission and scanning electron microscopy, X-ray microanalysis and light microscopy. Movements of ingested material have been followed by feeding the crabs with Mytilus edulis (L.) labelled with colloidal particles of gold or thorium oxide.
A key to marine species of Vannella (Sarcodina: Gymnamoebia), with descriptions of new species
Authors: Page F. C.
Published: May 2009

A key to all nine described marine species of naked lobose amoebae classified in the genus Vannella Bovee, 1965, is presented. All six species studied with the electron microscope have the characteristic surface structure found also in freshwater members of the genus. The key includes five species isolated from British waters, including three new species; a fourth new species is from the Persian Gulf area. Generic identification of Vannella, even in mixed material, can be made readily with the electron microscope, which is sometimes necessary for positive distinction from Platyamoeba. Further identification to species is a light-microscopical procedure. Members of this genus are cultured on bacteria, which are probably their main food in nature.
Seasonal variation in the strength of byssal attachment of the common mussel Mytilus edulis L.
Authors: Price Hilary Ann
Published: May 2009

A seasonal cycle in byssal attachment strength of Mytilus edulis is described in a population of mussels on the South Wales coast. Attachment strength reaches a maximum in September with a minimum in May.

INTRODUCTION

Many seasonal cycles of a physiological nature have been described in the common mussel Mytilus edulis L. (reviewed by Gabbott, 1976; also Pieters et al. 1978; Zurburg et al. 1978), some of which, for example the annual accumulation and subsequent utilization of energy substrates, appear to be linked to gametogenesis. Following spawning in the spring the gonads of Mytilus enter a resting phase; metabolic demands are low. Glycogen and protein are accumulated in the tissues at this time as phytoplankton is abundant. Gonadal development commences in autumn when phytoplankton density has declined and energy is supplied by the utilization of stored reserves. Pieters et al. (1978) have suggested that the resulting decline in reserves is accentuated by the need for greater byssus production at this time to secure the mussels against the rigours of autumn and winter storms. No accounts exist of field studies which might support this hypothesis.
Further studies of the effects of the anaesthetic quinaldine on the physiology of the intertidal teleostBlennius pholis
Authors: Milton P. , Dixon R. N.
Published: May 2009

The oxygen consumption of the intertidal teleostBlennius pholisL. has been investigated during and subsequent to quinaldine anaesthesia, using a continuous flow apparatus. Marked reductions in oxygen consumption were noted in high concentrations of quinaldine (10 and 20 ppm), and both entry into anaesthesia and recovery from it were rapid. A period of enhanced oxygen consumption followed anaesthesia, except in the lowest concentration of quinaldine (1 ppm). Experiments conducted over a 4 h period with three different salinities (100%, 30% and 10 % sea water) indicated that, under the influence of 10 and 20 ppm quinaldine solutions, the fish more resembled an osmoconformer than an osmoregulator. During anaesthesia, water was lost osmotically in 100% sea water, and gained in the more dilute salinities, although it was possible that some osmotic regulation continued. Physiological measurements indicated that quinaldine is suitable for the capture and marking of fish; for surgical procedures it should be mixed with another anaesthetic, for example MS-222, due to the retention of a response to vibratory stimuli.
Cellulase production in Sabella penicillus (Annelida: Polychaeta)
Authors: Lewis D. B.
Published: May 2009

From analyses of the gut content of Sabella penicillus L. Hunt (1925, as S. pavonina) showed that the food consists mainly of finely sorted plankton and detritus. The chief constituents were usually bottom-living diatoms, but planktonic forms when present made up the bulk of the food. Peridinians, silicoflagellates, foraminifera and tintinnids were also found to occur. These observations were confirmed by Nicol (1930) and in the present study, in which some individual worms were found to contain very large numbers of planktonic dinoflagellates, and pieces of red, green and brown algae, and encysted flagellates.
Corophium sextonaein Scottish waters
Authors: Moore P. G.
Published: May 2009

Recently, I wrote (Moore, 1978) that no substantiated records existed forCorophium sextonaeCrawford amend. Hurley (Amphipoda) north of Abereiddy Quarry, S. Wales. The records of the species for the West coast of Scotland given by Scarratt (1961, Ph.D. Thesis, University of Wales) have been regarded as suspect on the basis of wrongly labelled material from his type collection now (with his kind permission) in my possession. My own investigation of amphipods from kelp holdfasts in the Clyde Sea area and its environs, over many years have failed to produce this species.

C. sextonaehas now, however, been identified with certainty from a collection (made on 6 September 1979) ofAscidia mentulaMuller taken from a rope suspended (on 26 April 1979) from the U.M.B.S. raft in Linne Mhuirich, a marine lake off Loch Sween, lat. 55° 59′ N, long 5° 39′ W, O.S. ref. NR732853. Both male and ovigerous femaleC. sextonaewere included in the material. They were living in silty tubes attached to the tests of the ascidians, together withJassa falcata(Montagu) andMicrodeutopus anomalus(Rathke).

Personal collections of kelp holdfasts and other algae (Codium, ‘red algal turf’ mostlyBonnemaisonia) in the nearby rapids (ca. 3·2 km distant) at Linne Mhuirich in May 1969 (Moore, 1971, Ph.D. Thesis, University of Leeds) and in June 1974 (Shillaker & Moore, 1978) failed to disclose anyC. sextonae(allCorophiumwereC. bonnellii).C. sextonaemay be very localized within Linne Mhuirich, given Moore's (1978) observations on Lundy; the acknowledged unique hydrography of Linne Mhuirich (Kerr, 1912; Lewis & Powell, i960) and the sensitivity of the species to water movement gradients (Hughes, 1975).
The Decline of the Gastropod Nucella Lapillus Around South-West England: Evidence for the Effect of Tributyltin from Antifouling Paints
Authors: Bryan G. W. , Gibbs P. E. , Hummerstone L. G. , Burt G. R.
Published: May 2009

A survey of the gastropod Nucella lapillus around the south-west peninsula of England has revealed that the incidence of ‘imposex’, the induction of male sex characters in the female, is widespread, that all populations are affected to some degree and that the phenomenon is most prevalent along the south (Channel) coast. Populations close to centres of boating and shipping activity show the highest degrees of imposex, especially those within the vicinities of the Helford, Fal, Salcombe and Dart estuaries and in Plymouth Sound and Tor Bay. Within Plymouth Sound the degree of imposex increased markedly between 1969 and 1985, coinciding with the introduction and increasing usage of antifouling paints containing tributyltin (TBT) compounds.
An Analysis of a Stable Period in the Northumberland Benthic Fauna-1973–80
Authors: Buchanan John B. , Brachi Robin , Christie Graeme , Moore J. Jonathan
Published: May 2009

In the period 1973–80, the infauna at the standard 55 m station exhibited a high degree of persistence stability. The period was characterized by a stable biennial cycle in total numbers of individuals and substantial stability in species ranking. The biennial cycle was associated with density dependent mortality which appears as the principal controlling factor of the community. Evidence is discussed in support of the hypothesis that the density dependent mortality is due to interspecific and intraspecific competition, in a food limiting environment, between species with rather broad niche overlaps.