bluuebunny/crossref_metadata_2025 huggingface dataset:
Molecular Regulation of Muscle Growth in Crustacea
Authors: El Haj A.J. , Whiteley N.M.
Published: May 2009

Tissue growth in Crustacea occurs at specific stages of the moult cycle and is influenced by a number of physical, hormonal and environmental factors. In order to understand the mechanisms responsible for controlling intermittent muscle growth in Crustacea, the effects of various factors on rates of protein synthesis and gene expression for the myofibrillar proteins, have been examined. These studies include the effects of mechanical stretch on muscle fibres; the influence of the moulting hormones, ecdysteroids; and the effect of temperature which is an important environmental variable. Sarcomeric proteins have been cloned and used to measure mRNA levels of actin, myosin HC and tropomyosin in various muscles over the moult cycle. Results from these studies demonstrate that both transcriptional and translational regulation occurs in response to hormonal and mechanical stimulation. Temperature has a direct effect on rates of protein synthesis and transcription in intermoult muscles but overall protein turnover may remain unchanged due to a concomitant increase in protein degradation rates.
Dry Weight, Carbon and Nitrogen Content of Some Calanoid Copepods from the Seas Around Southern Britain in Winter
Authors: Lindley J.A. , John A.W.G. , Robins D.B.
Published: May 2009

The dry weights, carbon and nitrogen content of fresh dried Calanus spp. Pseudocalanus elongatus, Acartia clausi, Temora longicornis, Mesocalanus teniricornis, Metridia lucens and Candacia armata were determined from samples taken in the southern North Sea, the English Channel, the Irish Sea and the Celtic Sea in December 1984 and February 1987. Usually adult females were picked out but some data were obtained for adult males and copepodites of Calanus spp. and T. longicornis and male M. tenuicornis. Significant differences were found between stations on the same cruise in the results for adult females of the same species. The weights of Calanus spp. females in February 1987 were found to be inversely related to temperature.
Phorbol Ester-Induced Metamorphosis in the Parasitic Barnacle,Loxothylacus Panopaei
Authors: Glenner Henrik , Brodin Birger
Published: May 2009

In order to induce metamorphosis in cyprids of the parasitic barnacle Loxothylacus panopaei (Gissler) (Cirripedia: Rhizocephala: Kentrogonida), we tested a number of compounds (ZR-512, 20-hydroxyecdysone, 3-isobutyl-l-methylxanthine and phorbol-12,13- dibutyrate) all known to cause metamorphosis in thoracican barnacles. Only one agent, phorbol-12,13-dibutyrate, had an effect and induced cypris larvae to complete metamorphosis without previous attachment. This suggests that diacylglycerol-activated protein kinase C plays a role in the metamorphosis of kentrogonid rhizocephalans.

Rhizocephalans are highly specialized crustaceans adapted for parasitic life on decapods. The juvenile parasite passes through an internal growth stage, where a root-like trophic organ invades the tissue and haemocoelic fluid of the host (for detailed information on rhizocephalan life history, see Haeg, 1992). As in free-living barnacles, a cyprid larva is the settling stage, and in thoracicans a juvenile barnacle is formed underneath the carapace of the cyprid larva. However, the rhizocephalans develop a so-called kentrogon, which accomplishes the injection of the primordial parasite (Glenner & Høeg, 1995). The degree of specialization towards a specific host means that the cypris larvae of rhizocephalans are extremely selective in their choice of substrata. They will not settle unless a specific host or part of a host, e.g. the gills, is offered. For this reason, the study of settlement and metamorphosis of these species has met with great difficulties.
The population zoogeography of the common shrimp (Crangon crangon) in British waters
Authors: Henderson P.A. , Seaby R. , Marsh S.J.
Published: May 2009

The population structure of the common shrimp Crangon crangon (L.) in British waters is investigated. Samples were collected from 31 sites along the coasts of England, Wales, Holland, Belgium and France. Using a morphometric analysis it is concluded that English and Welsh waters hold six distinct populations. Animals belonging to the same population are found on the opposing English and continental coasts in the southern North Sea and English Channel which indicates that the avoidance of offshore waters is not isolating the shrimps. The boundaries between the populations are found to correspond with the boundaries between major plankton assemblages. It is suggested that the populations are isolated by the reduced dispersal of the planktonic larvae across fronts where bodies of water with different physical properties meet but incompletely mix.
The ethology of Crenilabrus melanocercus, with Notes on cleaning symbiosis
Authors: Potts Geoffrey W.
Published: May 2009

Off the coasts of the Eastern Aegean Island of Chios underwater observations were made on the labrid Crenilabrus (= Symphodus) ntelanocercus (Risso).

It was found that undisturbed observation could be made from 4 to 5 m away from the fish's territory, but if closer, then diver-orientated behaviour occurred. The fish might inspect the diver, or if alarmed, show fright reactions of different intensities. Conflict situations for the fish sometimes resulted in displacement chaffing. Pursuit caused the fish to show a series of escape reactions depending upon the intensity and persistence of the pursuit. Initially the fish showed avoidance reactions by fleeing or following set ‘escape routes’; further pursuit caused it to hide among the eel-grass, Posidonia; and finally aggregation and flight were resorted to.
Fatty-acid synthesis in the echinoderms:Asterias rubens, Echinus esculentusandHolothuria forskali
Authors: Allen W. V.
Published: May 2009

The fatty-acid compositions of tissue lipids ofAsterias rubensL.,Echinus esculentusL. andHolothuria forskaliDelia Chiaje were determined by means of gas-liquid chromatography. Considerable proportions of branched-chain, normal odd-numbered and eicosatetraenoic acids occur in the latter two animals. Tissues of all three animals were incubated with 1−14C-acetate. The relative specific activities of fatty-acid fractions isolated by thin-layer chromatography upon AgNO3-impregnated silica gel G fell in the order: saturates > monoenes — dienes > polyenes. The fatty-acid compositions of the alkoxydiglyceride, triglyceride and phospholipid classes of A. rubens hepatic caecal lipid were also determined.
The geographical distribution, population dynamics and reproductive biology of Boreomysis nobilis in Newfoundl and fjords
Authors: Clark Kirsten J. , Threlfall William
Published: May 2009

The hyperbenthic mysid, Boreomysis nobilis G.O. Sars, 1879 (Malacostraca: Peracarida), is reported from nine new locations around the island of Newfoundland in eastern Canada. It is commonest within and at the mouths of deep fjords and is less common or absent outside these fjords. Its absence from two bays where the depths, temperatures and salinities are all within the range inhabited by B. nobilis in other bays indicates that other factors are probably influencing local distribution patterns. The catch rates for B. nobilis are highest in the deep water within 150 m of the bottom. However, no differences were found in the vertical distribution of the different life-history stages of B. nobilis and no evidence was found for large-scale diel vertical migrations. Boreomysis nobilis was found to breed throughout the year, since all developmental stages were present on all sampling dates. However, there was a period of increased breeding activity in the late spring and early summer. An examination of the relationship between brood size, body volume of ovigerous females, and number of stage 1 larvae indicates that B. nobilis produced a smaller number of larger larvae than expected for epipelagic and coastal mysids
Populations of Streblospio (Polychaeta: Spionidae) in temperate zones: demography and production
Authors: Sardá Rafael , Martin Daniel
Published: May 2009

The life cycle, seasonal dynamics and production of two populations of Streblospio species (Annelida: Polychaeta), S. benedicti Webster, 1879, from muddy sediments of the Great Sippewissett Salt Marsh (southern New England, USA), and S. shrubsolii (Buchanan, 1890), from muddy areas of the Alfacs Bay (north-eastern Spain), were studied from November 1986 to September 1988. Both species have life-cycles shorter than one year. The American population showed a unimodal distribution most of the year while in the European population polymodal distributions were common. Average density of S. benedicti over the two-year period ranged from 24,086 to 677 individuals m−2 (annual average 4,554). The observed numbers of S. shrubsolii ranged from 65,668 to 2,579 individuals m−2 (average 35,311). The biomass of the American population ranged from 2·1 to 0·04g dry weight m−2 (average 0·5). The values obtained for the European population ranged from 5·9 to 0·1 g dry weight m−2 (average 4·1). Secondary production was higher in the European population (15·65 g dry weight m−2 y1) than in the American population (3·0 g dry weight m−2 y−1). Production to mean biomass ratios were 4·4 y−1 for S. shrubsolii and 5·4 y−1 for S. benedicti. Population densities are compared with previously published data for other Streblospio populations.
Colour polymorphism in idotea baltica from the Bay of Naples and its ecological significance
Authors: Guarino S. M. , Gambardella C. , Ianniruberto M. , de Nicola M.
Published: May 2009

In order to elucidate the ecological significance of polychromatism in Idotea baltica (Crustacea: Isopoda), the distribution of the various phenotypes was studied for three consecutive years in a population from the Bay of Naples. The most abundant morphs were uniformis (males: 394%-100%; females: 24·6%-84·1%) and maculata (males: 0·59·8%; females: 0%·50%), their distribution varying throughout the year. The assessment of some biological characters (females size, fecundity and embryonic stages of development) did not show any differences accounting for preferential fitness of these phenotypes. Moreover, it was observed that phenotypic diversity in colour morphs followed seasonal changes in the substrate composition. In agreement with other investigators, it has been suggested that the camouflage function of polychromatism may have a fundamental role in the reduction of predation, and favour Idotea baltica colonizing a variety of changeable habitats.
Chromosomes of the Sea Anemone Haliplanella Luciae (=H. Lineata) (Coelenterata: Actiniaria)
Authors: Fukui Yoko
Published: May 2009

Chromosomes of Haliplanella luciae (=H. lineata) (Verrill) were studied by a simple method that involved examination of Giemsa-stained preparations. The preparations were made from early embryos after fertilization in the laboratory. This is the first report of chromosome number for the acontiate sea anemones. A modal diploid number of 32 chromosomes was observed in metaphase plates. The method reported here is applicable to studies of chromosomes of other Actiniaria in which external fertilization occurs, with mature gametes being released from individuals of both sexes.
An Investigation of Detritus in Southampton Water
Authors: Trevallion Ann
Published: May 2009

An apparatus is described which has been used at three sites in Southampton Water for the continuous collection of sedimenting detritus. The collected detritus was removed at monthly intervals for measurement, and for analysis of the organic carbon and nitrogen content.

The total quantities of dry detritus varied from 4 mg/cm2/month to 980 mg/cm2/month, and because of the variable collection of resuspended bottom material show no clear seasonal variation. The carbon content was 0.1–7.3% of the total and nitrogen varied from 0.02 to 0.62%. The organic content did show some seasonal variation which tended to follow changes in the abundance of phytoplankton.

The amounts of total detritus collected and the organic content are high compared with some other areas and this is thought to be due partly to the high primary productivity of the area and partly to the complex water movements in the estuary.

Introduction

The importance of detritus in suspension in the sea and as a superficial layer on the sediment is well recognized. The quantity of detritus in sea water has been measured (Armstrong & Atkins, 1950; Fox, Isaacs & Corcoran, 1952; Krey, 1950, 1961a, b, 1964; Krey, Banse & Hagmeier, 1957; Hagmeier, 1962) and usually exceeds the amount of living material in suspension by at least a factor of ten. Study of deposited detritus has mainly involved measurement of the amount of organic matter in bottom sediments (Waksman, 1933; Anderson, 1939; Southward, 1952; Morgans, 1956; Sanders, 1960).

In studies of marine productivity it is important to know not only the amount of detritus present in the water column, but also its composition and rate of sedimentation.
The diet of the two-spot goby, Gobiusculus flavescens (Pisces)
Authors: Potts Geoffrey W. , Edwards Joan , Costello Mark J.
Published: May 2009

Juvenile and adult two-spot gobies, Gobiusculus flavescens (Fabricius), were collected at three sites in the Plymouth area: the Plymouth Breakwater, Fort Bovisand, and the Yealm estuary. Fish were sampled by a diver-held grab-net, boat-towed zooplankton net, and beam-trawl, from early June until the end of September 1987.

Percentage abundance and percentage occurrence dietary data are presented by a graphical technique, such that prey importance (rare or dominant) and fish feeding strategy (specialist or generalist), is visually apparent. It is applied to the different size groups of fish from each site.
Some observations on the behaviour of adult squids,Loligo forbesi, in captivity
Authors: Porteiro Filipe M. , Martins Helen R. , Hanlon Roger T.
Published: May 2009

Thirty-four adult individuals ofLoligo forbesi(males and females with dorsal mantle lengths from 27–77 cm) were observed in captivity in a 3 m diameter closed sea-water system on Faial Island, Azores. Squids were caught by jigging and were fed with horse mackerel (Trachurus picturatus) and chub mackerel (Scomber japonicus), either alive or dead. The maximum survival was 73 days. Feeding behaviour was dependent upon both the size of prey and its state of preservation;e.g.the squid would eat the head of small fish (< about 15 cm), reject the head of medium-sized fish (about 15–35 cm) and would eat only the dorsal part of a big fish (> about 35 cm) or a fish poorly preserved.

Seventeen chromatic, 9 postural and 6 movement components of body patterns were observed and described. Conspecific interactions considered to be aggression and dominance were observed among males; no such interactions occurred when one male and two females were kept together. Body patterns in relation to relaxation, stress, shock, feeding, locomotion and aggression are also described.
Calcium signalling at fertilization
Authors: Swann Karl , McDougall Alex , Whitaker Michael
Published: May 2009

It is generally agreed that fertilization in deuterostomes is accompanied by a large intracellular calcium wave that triggers the onset of development, but we still do not know exactly how the calcium wave is generated. The question has two parts: how does interaction of sperm and egg initiate the calcium wave, and how does the calcium wave spread across the cell? Two provisional answers are available to the first part of the question, one involving receptor-G-protein interactions of the sort that mediate trans-membrane signal transduction in somatic cells, the other injection of an activating messenger when sperm and egg fuse. Both these ideas are being actively pursued; the dialectic is productive, albeit no synthesis is in sight. We discuss their strengths and weaknesses. The second part of the question can now be much more precisely formulated: thanks to the recent flush of interest in calcium waves in somatic cells, new ideas and new experimental tools are available. The work on somatic cells repays a debt to eggs, where the basic properties of calcium waves were first set out, ten years before they turned up in somatic cells.
Bryozoan stolonal outgrowths: a role in competitive interactions?
Authors: Tzioumis Vicky
Published: May 2009

The use of stolons in competitive interactions between several species of bryozoans growing in Townsville Harbour, North Queensland is described. Stolonal growth resulted in overgrowth reversals and redirected growth in interactions between Schizoporella unicornis and Watersipora subtorquata. These results suggest that stolons may play an important role in bryozoan interactions
Analysis Of Condition and Swimming Performance in Juveniles of White Sea Bream,Diplodus Vulgaris
Authors: Planes S. , Hertel O. , Jouvenel J.-Y.
Published: May 2009

A pilot study was conducted to follow condition and swimming performances over two months using three samples of 50 juveniles of white sea bream,Diplodus vulgaris. The initial result indicated that the weight-length relationship followed the model; W=5.2xl0-3L349. According to this relationship, condition indices were estimated for each individual as the observed weight related to the computed weight. Measures of swimming velocities realized in an artificial flume show variations through time with an increase and decrease directly correlated to condition indices. Maximum speed of an individual was measured at 12.3 cm s1. Analysis of environmental conditions indicated that the decrease of condition index and swimming performances was related to bad weather which induced turbid water in juvenile habitats.
The relation between the dimensions of the cirral net, the beat frequency and the size and age of the animal in Balanus balanoides and Elminius modestus
Authors: Crisp D.J. , Maclean F.J.
Published: May 2009

The expected allometry between the linear cirral length and animal volume or weight for isometry should be 0·33; similarly the rate of beating, db/dt, might also be expected to increase as −0·33 with volume. The average allometry index of cirral length is less in both Balanus balanoides (0·22–0·23) and in Elminius modestus (0·27–0·32). The segment numbers also rise less than expected.

The rate of beat in Balanus balanoides correlates well with size (-0·28) and with temperature with a correlation coefficient of 0·898, significant for both variables. For a group of 11 species the relation between maximum rate of beating and size over 5 decades gives an approximate allometry of −0·24 which is also less than the expected −0·33 for an isometric linear appendage moving at constant velocity. It is suggested that the approximately reciprocal allometry index between cirral beating rate (−0·28) and cirral length (+0·22) may be mutually compensating, resulting in the cirri moving through the water at a constant rate during the growth of the animal. This rate may maximise the chance of prey being captured.
The relationship between the distribution of genetically distinct inbred lines and upper lethal temperature in Lasaea rubra
Authors: Walters-Tyler H. , Davenport J.
Published: May 2009

Lasaea rubra is an inbreeding bivalve species, living at most heights on rocky shores. Freshly collected animals from different shore heights showed significantly different upper median lethal temperatures (MLTs), with upper shore animals having higher MLTs than lower shore specimens. Experiments with animals acclimated for at least one month to a single temperature (15°C) demonstrated that these differences in upper MLT were unaffected by thermal acclimation. Electrophoretic investigation showed that the differences in thermal response had a genetic basis. Homogeneous populations of the high-water inbred line (‘Inbred line A’) had a higher MLT than homogeneous populations of ‘Inbred line C’ which was found on the middle and lower shore. No differences were detected between the MLTs of separate populations of Inbred lines A or C. A third inbred line (‘Inbred line B’) was found on the middle shore, but no homogeneous populations were found. However, indirect evidence suggests that Inbred line B has a thermal response intermediate between those of Inbred lines A and C. Study of populations made up of mixtures of inbred lines confirmed the relationship between upper MLTs and genetic composition of the population.
Gastropod predation sites: the role of predator and prey in chemical attraction of the hermit crabClibanarius vittatus
Authors: Rittschof D. , Kratt C.M. , Clare A.S.
Published: May 2009

Gastropod shells are essential to most hermit crabs. Shell availability limits hermit crab populations. Shells provide protection and the degree of shell-fit controls crab growth and fecundity. Crabs locate new gastropod shells from a distance under water by molecules released from gastropod flesh during predation events. Here we test the hypothesis that the salivary glands of the predatory gastropod are the source of enzymes that digest muscle proteins and release peptide attractants. We describe the anatomy of both the acinous salivary glands and the tubular accessory salivary glands ofBusycon contrariumwhich are similar to those ofB. carica. The salivary gland ducts empty at the mouth, suggesting a role in the primary digestion of food. We show that gastropod muscle proteins, extracted by salt solutions with the ionic strength of sea water and purified by precipitation in low ionic strength can be digested by gastropod salivary gland enzymes to generate peptides attractive to the hermit crab,Clibanarius vittatus, in field assays.
A comparative study of the closure responses of some cirripede species exposed to falling seawater concentrations
Authors: Cawthorne Derek F.
Published: May 2009

The closure response to low external salinity of three species of intertidal and estuarine barnacle (Balanus balanoides, B. crenatusandElminius modestus) when exposed to various rates of salinity change were investigated. Comparisons were made between the responses of specimens collected from estuarine and coastal sites. In addition the responses of the brackish water barnacleBalanus improvisuswere measured.
The cytochemical distributions of zinc (Zn II) and iron (Fe III) in the common mussel, Mytilus edulis, and their relationship with lysosomes
Authors: Lowe D. M. , Moore M. N.
Published: May 2009

Zinc (Zn II) and iron (Fe III) were demonstrated histochemically in cytoplasmic inclusions shown to be lysosomes in a number of cell types in Mytilus edulis. The cellular distribution of the metals differed between the sexes; males were shown to have more zinc (Zn II) in the kidney than females, the latter appearing to use oocytes as an additional means of excretion. Differences in cellular distribution of the metals was also demonstrated between the two populations studied probably reflecting availability of the metals in their respective environment.
On the distribution of major nutrients and phytoplankton in the Tamar estuary
Authors: Mommaerts J. P.
Published: May 2009

The estuary of the Tamar has been surveyed from March to September 1968. Salinity distributions and variations have been measured with the object of providing a preliminary picture of the general circulation. Tidal flows appear to have most effect on water movement in the estuary.
Pigmentation and carotenoid metabolism of the marine isopod Idotea metallica
Authors: Herring Peter J.
Published: May 2009

Idotea metallica Bosc is a dark-brown or blue-black species, its colour being controlled largely by the degree of expansion of, and pigment concentration in, the dermal chromatophores. In addition, the iridophores produce the characteristic metallic sheen by Tyndall scattering.
Life at low oxygen tensions: the behaviour and physiology ofNautilus pompiliusand the biology of extinct forms
Authors: Wells M.J. , Wells J. , O'Dor R.K.
Published: May 2009

Nautiluscan survive for long periods in water of very low oxygen content. Below a PO2of around 25 mm Hg activity becomes intermittent, with brief periods of jet propulsion punctuating longer (typically 15–20 min) periods at rest. During these inactive periods ventilatory movements cease and the heartbeat slows to one or two cycles of very low amplitude per minute. The onset of an active period is heralded by an increase in heartbeat frequency and amplitude and a resumption of visible ventilatory movements. The large blood volume and very high oxygen affinity of the blood pigment apparently ensure that the animal accumulates sufficient oxygen during the resting intervals to fuel the brief active periods. Recovery, even after prolonged exposure to near anoxic conditions, is very rapid if the animal is exposed to well-aerated water. These capacities are not only related to a strategy of defence by withdrawal but would also allowNautilusto exploit environments where the low oxygen content might limit competition from most fish and crustaceans. It is argued that aNautilus-like physiology and behaviour could well have contributed to the success of extinct ectocochleate forms, living in oceans that were, by and large, less well oxygenated than now. The downward extension of oxygen-rich water and progressive elimination of hypoxic regions from the continental shelves during the Mesozoic may have contributed to the extinction of the ectocochleates by opening up the hitherto hypoxic environments, which they were adapted to exploit, to the more strictly aerobic high metabolic rate competitors and predators that eventually replaced them.
On the regulation and maintenance of algal numbers in zooxanthellae-coelenterate symbiosis, with a Note on the nutritional relationship inAnemonia sulcata
Authors: Taylor D. L.
Published: May 2009

The regulation of total algal numbers in the symbiosis involving Anemonia sulcata and a marine dinoflagellate has been investigated in a series of experiments designed to test the effects of starvation and/or darkness on the host and its alga. The gross effect of these conditions (either separately or in combination) is detectable as a generalized weight loss in the symbiotic system. An electronmicroscopical study has shown that this weight loss can be directly related to changes in the ultrastructural morphology of both Anemonia and its symbionts. The significance of these findings is discussed in relation to current knowledge of the nutritional aspects of algal—invertebrate symbiosis.
Effect of Feeding on the Structure of the Digestive Gland of the Tropical Sepioid Idiosepius Pygmaeus
Authors: Semmens Jayson M. , Moltschaniwskyj N.A. , Alexander C.G.
Published: May 2009

The digestive gland of the tropical sepioid Idiosepius pygmaeus (Steenstrup) (Cephalopoda: Idiosepiidae) is characterized by a single cell type which secretes proteinaceous spherical bodies, the secretory spheres. Changes in the structure of the gland with feeding were investigated through a field sampling programme and a laboratory feeding experiment. Specimens were collected in the field on three consecutive days. There was a significant increase in the number of spheres during the day. A laboratory-based night trial showed that numbers of secretory spheres remained high during the night. After feeding there was a rapid and marked increase in the number of secretory spheres, suggesting that upon registering a stimulus the digestive gland secretes large amounts of enzymes. The process is rapid with an increase in the number of spheres occurred one hour after feeding. A second peak occurred 16 hours after feeding, suggesting that there may be two phases to the digestive cycle. This study examined natural and experimental patterns in the digestive gland and estimated the time involved in the digestive activity of I. pygmaeus.
Beak Length Analysis of Moroteuthis Ingens (Cephalopoda: Onychoteuthidae) from the Falkland Islands Region of the Patagonian Shelf
Authors: Jackson George D. , Buxton Nicole G. , George Magnus J.A.
Published: May 2009

A detailed analysis of beak length to body length and weight measurements was carried out for the onychoteuthid squid Moroteuthis ingens, in the Falkland Islands region of the South Atlantic. Lower and upper rostral lengths were both good predictors of mantle length and body weight. In addition, the relationships of freshly dissected beaks to mantle length and body weight were significantly different to those of beaks dried before measuring, with dried beaks being better predictors of both variables.

A considerable amount of information on Southern Ocean squid biology has been obtained from analysis of beaks in the stomach contents of predators (Clarke, 1980,1983). Beak analysis can be particularly useful as it provides information on the species preyed upon as well as estimates of squid size and biomass ingested (Clarke, 1983, 1986).
A ‘Hyaline’ Layer in the Skin of Squids
Authors: Madan J.J. , Wells M.J.
Published: May 2009

The skin ofLoligo vulgarisandIllex illecebrosuscontains a thick layer of amorphous material. InLoligoit lies above and inIllexbelow the chromatophore layer. We can find no mention of this layer in the considerable literature on squid skins despite its potential importance as a protection to underlying tissues and as a possible barrier to cutaneous oxygen uptake.

Cephalopods have soft complicated skins. Embedded in the skin, most species have chromatophores, small bags of pigment that can be expanded by muscles that are under direct nervous control from the brain. There is an extensive literature on the physiology of chromatophores (Packard, 1988) and on their function in the behaviour of the animals (Hanlon & Messenger, 1996; Packard & Hochberg, 1977). Further cutaneous structures concerned in the determination of the colour of living cephalopods, the reflecting iridophores and leucophores (Cloney & Brocco, 1983), and the light generating photophores (Herring, 1988), have been the subject of a number of reports but other skin features such as the distribution of blood vessels have attracted little attention.
The deep-sea nematode Thalassomonhystera bathislandica sp. nov. and microhabitats of nematodes in flocculent surface sediments
Authors: Riemann F.
Published: May 2009

Thalassomonhystera bathislandica sp. nov. (Nematoda: Monhysteridae) was found in abundance in a few gelatinous phytodetritus aggregates collected from the surface of bottom sediments in the north-eastern Atlantic at depths of about 4000 m. The new species resembles T. islandica (De Coninck, 1943), an inhabitant of saltmarshes. Viscous detrital aggregates, including sediment agglutinations made by the nematodes themselves, are perceived as the preferred habitats of nematode species in fluffy surficial muds. It is suggested that physical constraints prevent nematodes from a fast invasion into freshly sedimented, loose detritus deposits.
The Seasonal Succession of Appendicularians (Tunicata: Appendicularia) off Plymouth
Authors: Acuña J. L. , Bedo A. W. , Harris R. P. , Anadón R.
Published: May 2009

Earlier descriptions showed that the community of appendicularians off the British coast was mainly composed of Oikopleura dioica (Appendicularia; Müller, 1846) and Fritillaria borealis (Appendicularia; Lohmann, 1896), rarely by Oikopleura fusiformis (Appendicularia; Fol, 1872) and Fritillaria pellucida (Appendicularia; Quoy & Gaimard, 1833) and exceptionally by Oikopleura longicauda (Appendicularia; Vogt, 1854). Based on weekly samples collected during 1989 at a single station off the coast of Plymouth, we describe the first complete seasonal cycle of appendicularians in this area. The results suggest that rather than being occasional visitors, O. fusiformis, F. pellucida and O. longicauda are consistently present and abundant from mid to late summer. Moreover, the seasonal shifts in structure of the community of appendicularians in the area, as depicted by multivariate analysis, are consistent with those of the more southerly central Cantabrian coast (Spain). This suggests that they are viable populations rather than occasional expatriates from other areas.
Tharyx retierei, a new species of Cirratulidae (Annelida: Polychaeta) from the Atlantic coast of Morocco
Authors: Lechapt Jean-Paul
Published: May 2009

Tharyx retierei, a new species of bipalpate Cirratulidae (Polychaeta), has been collected from subtidal depths south of Safi, off the Atlantic coast of Morocco. The species differs from all other known bipalpate cirratulids in possessing aristate and pseudocompound neurosetae in posterior segments. The species is described and figured and its affinities are briefly discussed.
Indoleamine-induced encystment in dinoflagellates
Authors: Wong J.T.Y. , Wong Y.H.
Published: May 2009

Six species of dinoflagellates were investigated for their responsiveness to the indoleamine melatonin (and its homologue 5-methoxytryptamine), the vertebrate hormone for circadian rhythm regulation. Five species were observed forming pellicle cysts in response to 5-methoxytryptamine at concentrations around 10−6M. Cells of Oxyrrhis marina were observed retracting from the theca, part of the responsive pathway to indoleamine, but the resulting naked cells were unable to form a new cell wall and lysed.
The Occurrence of Seriola Rivoliana (Osteichthyes: Perciformes: Carangidae) on the British Coast
Authors: Wheeler Alwyne
Published: May 2009

On the night of 4–5 August 1984 an unusual fish was captured in a trammel net set in Elbery Cove, Torquay, South Devon, by Mr W. Blackmore. Its captor realizing it was an unusual species forwarded it to Mr A. D. (Tony) Mattacola for identification. Tony Mattacola recognized it as a member of the genus Seriola, and using the works of Berry & Burch (1979) and Randall (1968) tentatively identified it as Seriola rivoliana Valenciennes, 1833, a species which had never hitherto been recognized in northern European seas. The identification of the specimen was confirmed when the specimen was sent to the author at the British Museum (Natural History); register number 1984.10.22.1.
Trace Metal Uptake and Sodium Regulation inGammarus MarinusFrom Metal Polluted Estuaries in England
Authors: Wright David A.
Published: May 2009

The regulation of major ions in aquatic Crustacea has been extensively studied, and it is hardly surprising that ever-present ionic constituents of sea water such as sodium, potassium, chloride, calcium and magnesium have been incorporated into highly efficient regulatory mechanisms. On the other hand, we know little of the mechanisms governing the uptake and regulation of trace elements, despite the fact that metals such as zinc and copper may be important constituents of enzymes and blood pigment.
Alectona Species From North-Western Pacific (Demospongiae: Clionidae)
Authors: Bavestrello Giorgio , Calcinai Barbara , Cerrano Carlo , Sarà Michele
Published: May 2009

Alectona species which bore into the scleraxis of several colonies of Corallium elatius and the stem of a stylasterid coral, Distichopora sp. have been studied. The genus Alectona consists of rarely collected species. Five species, of the eight known for the genus, are here recorded. Two new species of Alectona sorrentini and A. microspiculata and one uncertain species are described.

In recent reefs Cliona species are the predominant boring sponges while Alectona and Thoosa were common in the Eocene/Miocene coral reefs. The deep precious red coral communities of the western Pacific may be interpreted as refuge habitats of these ancient boring sponges.
Swimming behaviour of the larvae of Pecten maximus (L.) (Bivalvia)
Authors: Cragg S. M.
Published: May 2009

Laboratory observations indicate that larvae of Pecten maximus (L.) pass through three phases of swimming behaviour before metamorphosis. Trochophores and early veligers generally swim upwards and, in shallow containers, tend to accumulate at the surface. Their swimming cilia beat without interruption so swimming is continuous. After 3 days of development, pauses in ciliary beating occur intermittently and the veliger becomes capable of withdrawing into its shell. It alternately swims up a vertically orientated spiral and sinks. This type of swimming behaviour is also displayed by the pediveliger, but this larva also periodically swims close to, or crawls on, the substratum. The tendency to accumulate at the surface becomes less pronounced as larvae grow older. By the pediveliger stage it is replaced by an increasing tendency to accumulate close to the substratum.
The accumulation of ferric iron in the guts of some spatangoid echinoderms
Authors: Buchanan J. B. , Brown B. E. , Coombs T. L. , Pirie B. J. S. , Allen J. A.
Published: May 2009

The connective tissue layer of the large intestines of Brissopsis and Echinocardium spp. is shown to contain a massive quantity of ferric iron in the form of ferric phosphate. The ferric phosphate is present as a granular extracellular deposit. In large mature specimens of Brissopsis, the weight of iron present may account for almost 30% of the dry weight of large intestinal tissue. The iron deposit appears to be cumulative with age. It is speculated that the deposit is derived from oxidative deposition of a soluble ferrous salt ingested in reducing conditions.
Coscinodiscus nobilis (Grunow) in continuous plankton records, 1977–78
Authors: Robinson G. A. , Budd T. D. , John A. W. G. , Reid P. C.
Published: May 2009

Results from the Continuous Plankton Recorder (CPR) Survey have been used to extend the observation by Boalch & Harbour (1977 a) of the occurrence in January 1977 of a diatom Coscinodiscus nobilis (Grunow), new to British waters. Samples have been taken by the CPR to the west of the British Isles since 1948 and along the English Channel since 1957. C. nobilis was not identified until the spring of 1977, thus confirming the observations by Boalch & Harbour. It reappeared in 1978 when it was found further north in the Irish Sea.
On the feeding habits of Aphrodita aculeata and commensal polynoids
Authors: Mettam C.
Published: May 2009

A recent review of polychaete diets (Fauchald & Jumars, 1979) considered aphroditids to be slow-moving carnivores, taking microscopic prey if nothing else is available but specializing in slow-moving or sessile prey. This opinion was based on remarks by Day (1967) and on two documented gut analyses of Aphrodita aculeata (Blegvad, 1914; Hunt, 1925). Other reports in the literature were either derived from these few original statements or else gave unsubstantiated accounts of the type of food taken.

In 1964 the late Gunnar Thorson told me that he had seen a specimen of A. aculeata swallowing a large Nereis virens and likened it to a hedgehog eating a snake. This vivid analogy puts Aphrodita in a rather different light, as an active predator capable of dealing with relatively large, powerful prey. In fact Hunt (1925) had recorded remains of ‘Pectinaria, Lumbriconereis, Polynoidae and Nereidae’ in 24 out of 26 specimens containing food. Very young crabs and hermit crabs were recorded in five guts and a nemertean in one. Blegvad (1914) recorded the chief food to be other worms, especially sabellids and terebellids, besides nemerteans, from examination of 50 specimens, 35 of which were empty.

I have kept A. aculeata, obtained from Millport and from Plymouth, in bowls containing several centimetres depth of beach sand in a closed-circuit sea-water system. Worms without sand took no interest in items offered as food, neither did worms which had emerged from the sand and were wandering over the surface, but buried worms fed readily. A variety of living animals was given as potential food including Macoma balthica, Corophium volutator, Nephtys hombergi and Nereis diversicolor.
The abundance and distribution of the eggs and larvae of some teleost fishes off Plymouth in 1969 and 1970 II. The postlarvae of Callionymus
Authors: Demir Necla
Published: May 2009

The development of Callionymus reticulatus Valenciennes, 1837, from the early postlarval stage (2·7 mm) up to about the end of metamorphosis (11·4 mm) is described. The main differences between its postlarvae and the postlarvae of C. lyra Linnaeus, 1758 and C. maculatus Rafinesque-Schmaltz, 1810 are described and illustrated. The spawning periods of the three Callionymus species are briefly discussed and the seasonal occurrence and distribution of their postlarvae off Plymouth are given.
The vertical distribution and diurnal migrations of calanoid copepods collected on the Sond cruise, 1965 IV. Systematic account of families Lucicutiidae to Candaciidae. the relative abundance of the numerically most important genera
Authors: Roe H. S. J.
Published: May 2009

The vertical distributions and diurnal migrations are analysed for nineteen species of calanoid copepods in the families Lucicutiidae up to and including the Candaciidae. The relative abundance, both vertical and horizontal, is given for each species.

With few exceptions most of these species show little or no vertical migration. There is some suggestion of a reversed (downward) migration for Paracandacia bispinosa andP. simplex but since there are difficulties in analysing the surface samples the evidence is inconclusive. The species which are abundant in the family Heterorhabdidae all have little or no vertical migration and are at least partially vertically segregated by both day and night. Phyllopus impar and P. helgae are clearly vertically segregated and Haloptilus acutifrons and, to a lesser extent, H. ornatus each have two vertically separated populations by both day and night. Two size groups are present in each sex of Lucicutia flavicornis.

The vertical distributions and numbers throughout the water column are analysed for 203 and 176 species in the day and night series respectively; it is concluded that while many species are relatively abundant at one or more particular depth most of them are numerically relatively insignificant in the water column as a whole. Only two species (day) and four species (night) formed more than 5 % of the total numbers caught in their respective series.

The relative abundance, both vertical and horizontal, of the commonest genera are analysed. In the whole water column the relative abundance of most of the genera is constant by both day and night, and, as with the individual species, most of them are relatively scarce.
Myxilla tarifensis sp. nov. (Porifera, Poecilosclerida), with remarks on the genus Myxilla in the Strait of Gibraltar (Iberian Peninsula)
Authors: Carballo J. L. , García-Gómez J. C.
Published: May 2009

A new Myxillidae species from the Strait of Gibraltar, Myxilla tarifensis, is described. It is easily distinguished by a characteristic irregular isodictyal reticulation of acanthostyles which are smooth or slightly spined at the heads, as well as by strongyles as ectosomical megascleres, sometimes with very small and short spines at the ends. Moreover, the recent synonymization of the genera Dendoryx, Burtonanchora and Pseudomyxilla is accepted. A brief diagnosis is given of the Myxilla species found in the Strait of Gibraltar.
Structure and function of the fifth pair of pleopods of male Euchaeta norvegica (Copepoda: Calanoida)
Authors: Hopkins C. C. E. , Mauchline J. , Mclusky D. S.
Published: May 2009

The structure of the fifth pair of pleopods, modified as secondary sexual characters, in male Euchaeta norvegica is described in detail. The pleopods are biramous. The right pleopod, of relatively simple structure, is used solely to grasp the urosome of the female during transfer and placement of the spermatophore. The left pleopod is complex in form and is used to grasp the spermatophore as it is extruded from the ductus ejaculatorius. The method of grasping the spermatophore is described. The optimal mating position is deduced from the structure and functioning of the pleopods.
New Observations on a Rare Physonect Siphonophore,Lychnagalma Utricularia(Claus, 1879)
Authors: Pugh P.R. , Harbison G. R.
Published: May 2009

A rare physonect siphonophore,Lychnagalma utricularia(Claus, 1879), is redescribed from 24 specimens collected in the region of the Bahamas by the submersible D.S.R.V. ‘Johnson-Sea-Link II’. It was the most common siphonophore collected by the submersible, using its sophisticated sampling techniques. The paucity of previous records for the species, and thus its apparent rarity, is probably due to the extreme fragility of the animals which causes them to disintegrate on contact with nets. The status of the second species,L. vesiculariaHaeckel, 1888, is reviewed and it is concluded that it should be reduced to a junior synonym ofL. utricularia.
On the nutrition and metabolism of zooplankton XIII. Further studies of steroids inCalanus
Authors: O'Hara S. C. M. , Gaskellf S. J. , Corner E. D. S.
Published: May 2009

The presence inCalanus finmarchicusof the sex hormone oestradiol-17β has been confirmed by gas chromatography-mass spectrometry (GC-MS) using the trimethylsilyl and heptafluorobutyrate derivatives.

Levels of the sex hormone testosterone have been measured by radioimmunoassay inCalanus helgolandicuscollected from Plymouth Sound, and inC. finmarchicuscaptured off the Norwegian coast. Concentrations inC. helgolandicusvaried during the year from 150 to 626 fg/animal, accounting for 2.3 to 437 x 10-7% of the lipid content and 10.8 to 64.8 x 10-6%percnt; of the total sterol fraction. The mean level in Stage V C.finmarchicus,captured during spring, was 196 fg/animal.

Testosterone was identified in C.finmarchicusby GC-MS of thetert-butyldimethylsilyl derivative.
Fish otoliths from the stomach of a thresher shark, Alopias vulpinus
Authors: Pascoe P. L.
Published: May 2009

INTRODUCTION

On the 16 June 1982 a thresher shark, Alopias vulpinus (Bonnaterre, 1788), became entangled in a gill net at Bigbury Bay, S. Devon. The stomach contents were found to consist solely of teleost otoliths. The soft tissues of prey taken by large marine predators are often macerated and digested very rapidly or, as in this case, regurgitated during capture or stranding. Identification of the prey is therefore only possible from the hard parts which often remain, e.g. teleost otoliths, bones and scales, and cephalopod beaks, statoliths and gladiuses. The regular seasonal occurrences in the waters off south-west England and south-west Ireland make the thresher the most common of the large sharks in this area. Their accidental capture or collisions with nets are not rare and they have been taken by rod and line on several occasions.
Occurrence, composition and function of intracellular calcium phosphate granules in the musculature of nephtyid polychaetes (Annelida)
Authors: Bryan G. W. , Gibbs P. E.
Published: May 2009

INTRODUCTION

Intracellular calcium granules rich in phosphorus are found throughout the animal kingdom and occur in a wide range of different tissues (Simkiss, 1976; Mason & Nott, 1981). However, few examples of the natural occurrence of such granules in muscle cells have been recorded and thus the discovery of abundant granules composed of calcium phosphate within the muscle fibres of the polychaeteNephtys, described by Gibbs & Bryan (1984), is of considerable interest, particularly regarding the formation and function of these unusual sarcoplasmic inclusions.
Modalities of brooding and morphogenesis of larvae in Ostrea puelchana (D'Orbigny) under experimental rearing
Authors: Castro Nora Fernandez , Pennec Marcel Le
Published: May 2009

Ostrea puelchana is a larviparous oyster from the S.W. Atlantic coasts. This species is not being commercially exploited at present. Because of its high food qualities, however, it may constitute a resource of economic interest in the future.

Until now larval development and characteristics of the incubation period have been poorly known. This study describes the characteristics of the mode of brooding under laboratory rearing conditions and, using scanning electron microscopy, the morphogenesis of the hinge until larval release from the parents.

The larva develops two anterior and two posterior denticles during brooding. A comparison with larvae of other species of the genus Ostrea reveals that the main differences among them do not lie so much in the pattern of hinge dentition as in the rate of evolution of the hinge components, which is faster in Ostrea puelchana. This species has fully developed denticles at the time of release, which places the larva of this oyster as particularly evolved within the genus Ostrea.