bluuebunny/crossref_metadata_2025 huggingface dataset:
The Biology ofLoligo ForbesiSteenstrup (Mollusca: Cephalopoda) in the Plymouth Area
Authors: Holme N. A.
Published: May 2009

The distinguishing features of the common squid of British waters,Loligo forbesi, are summarized, and contrasted with those ofL. vulgaris.The life-cycle and growth ofL. forbesiare described, based on samples from trawl catches off Plymouth. This species seems to be an annual - young squid first appear in the trawl in late May, when their length is about 10 or 11 cm. Subsequent growth is rapid, and the males reach 30 cm and the females 25 cm by November. Spawning takes place mainly in December-January, but may continue into the spring. Neither sex survives beyond a single spawning season. Hatching of the spawn probably takes 30–40 days, and if the young squid taken in the trawl in late May hatched in the early part of the same year, a growth rate of about 25 mm/month would be required. Known growth rates for other species ofLoligoare about 20 mm/month, so that indicated forL. forbesidoes not seem to be impossibly high. The life-cycle is summarized in Fig. 8. There is also a summer spawning population, which grows to a rather smaller size at maturity, and which also seems to be annual.

During the summerL. forbesiranges throughout the English Channel and southern North Sea, particularly in inshore areas. In October the squid migrate farther offshore and tend to occupy the western part of the Channel.

Values for total weight of squid/2 h trawl are given, on a monthly basis, for 1966–9. The largest quantities are usually taken in October and November, the highest single figure being 30.54 kg/2 h trawl, in November 1967.
Endogenous Rhythmicity Associated with Larval Hatching in the Lobster Homarus Gammarus
Authors: Ennis G. P.
Published: May 2009

A nocturnal larval hatching rhythm is described for the lobster Homarus gammarus. In natural illumination cycles, hatching takes place shortly after darkness with the hatching process lasting for about 1 min or less. One female lobster can release batches of larvae each successive night for periods of from 2 to 6 weeks, depending on size and water temperature during the period of hatching. The hatching rhythm persists, though slightly out of phase, when lobsters that have been releasing larvae for some time are kept in constant darkness, but in constant illumination hatching may be delayed for 2 or 3 days and when it does occur it is erratic and non-rhythmic. Larvae that do hatch in constant illumination appear to do so without parental assistance. Onset of darkness synchronizes the rhythm but an endogenous component is involved in controlling it.
Depth Distribution of the carotenoid pigments and lipids of some oceanic animals. 2. Decapod Crustaceans
Authors: Herring P. J.
Published: May 2009

Analysis of the carotenoid pigments of decapod crustaceans has indicated that the visible differences in the appearance of species from different depth horizons are largely due to the disposition of pigments and not to differences in total amount of pigment relative to body size. Species from the upper mesopelagic zone have relatively few large chromatophores, and their chitin is either unpigmented or feebly pigmented. Species from deeper zones have very many small chromatophores and chitin heavily pigmented by unesterified astaxanthin. The major carotenoid pigments of almost all species are astaxanthin and its esters.

Lipid analyses have shown that several species of Caridea have very high levels of lipid in the body, and that in many deep-water species wax esters comprise a large proportion of the total lipid. Specific patterns of distribution of the various lipid classes are found in different tissues, with wax esters particularly dominating the hepatopancreas lipids of deep-living species.

The patterns of pigment and lipid distribution are discussed in relation to the depth distribution, light environment, and metabolic requirements of the different species.
Inter-moult growth of species of Mysidacea [Crustacea]
Authors: Mauchline J.
Published: May 2009

Adult female mysids do not moult while carrying young in the marsupium. Successive larval stages can be recognized in the marsupium and this allows examination of the body length of the parents at different points in the inter-moult period. The body length of 13 species of mysids was found to have increased during the course of the inter-moult period; the average increase in length of the body is 7%. An examination of the ratio of abdomen length to carapace length at different points in the inter-moult period shows that this growth in length is accommodated in the abdomen.
A Note on the Buoyancy of some Lantern-Fishes (Myctophoidei)
Authors: Bone Q.
Published: May 2009

The buoyancy, lipid levels, and orientation of five species of myctophid from the Biscay area were examined, and it was found that two of the five were probably normally denser than the sea water in which they live. Analysis of the swimbladder gas of Myctophum punctatum collected at the surface at night indicated that this species has a less extensive vertical range in this area than elsewhere. A functional classification of myctophids is proposed, based upon density, lipid levels, and the presence or absence of a gas-filled swimbladder.
Preliminary studies on the lipid metabolism ofNeomysis integer, Involving Labelled Feeding Experiments
Authors: Morris R. J. , Ferguson C. F. , Raymont J. E. G.
Published: May 2009

A series of controlled, labelled feeding experiments were carried out onNeomysis integerin order to investigate its lipid metabolism. The techniques of thin-layer chromatography, preparative column chromatography, analytical and preparative gas-liquid chromatography and low-background14C counting were used to follow the incorporation of a14Clabelled fraction from a range of diets into the animal's lipid.Neomysis integerwas found to be capable of converting dietary starch or short-chain saturated fatty acids to longchain polyunsaturated fatty acids, which were then incorporated into the TG and PL fractions.
The Distribution of Glycogen in the Tissues ofSiboglinum Atlanticum[Pogonophora]
Authors: Southward Eve C.
Published: May 2009

Light and electron microscopy showed the same distribution of glycogen. The peritoneal cells contain large amounts in all three body regions investigated: the forepart, metameric region and postannular region. Glycogen is present in most epidermal cells and is very abundant in some, particularly in the postannular region, but the cells which secrete the chitinous and proteinaceous components of the tube are almost devoid of glycogen.
The Effect of Supplementary Algal Feeding of a Hatchery Breeding Stock of Ostrea Edulis L. on Larval Vigour
Authors: Helm M. M. , Holland D. L. , Stephenson R. R.
Published: May 2009

Adult European flat oysters, Ostrea edulis L., receiving a food supplement of the unicellular alga Tetraselmis suecica (Kylin) Butch, during laboratory conditioning for spawning produced more broods of larvae than oysters receiving only the natural phytoplankton in the seawater supply. Many of the broods from adults receiving this extra food were liberated sooner, and these larvae grew at an enhanced rate and provided greater spat yields than the broods from the control stock. The viability of larvae, which was significantly correlated with their lipid, and in particular neutral lipid, proportion at the time of liberation, declined as the length of the stock-conditioning period prior to female spawnings increased. This may be related to the decline in the dry meat weight and the condition factor of the adult oysters during the experiments irrespective of the feeding regime. The extra algal ration provided a check to the decline in dry meat weight of the food-supplemented adults.
Procedures for Calculating the Osmotic Coefficient of Artificial Sea Waters
Authors: Whitfield M.
Published: May 2009

Recent equations for calculating the osmotic coefficient of sea water from the properties of the component single-electrolyte solutions are discussed. Two equations are introduced that together provide accurate predictions of the osmotic coefficient of sea water for ionic strengths up to 4 M (equivalent to a fivefold concentration of standard sea water). Since they take into account the detailed solution composition these equations should be useful for calculating the osmotic coefficients of estuarine waters and of biological salines where procedures based on curve fitting to standard sea-water data may be inapplicable. Extensions of the calculations to cover a wide pressure and temperature range are discussed in some detail.
An improved Bottom-water Sampler
Authors: Joyce J. R.
Published: May 2009

A device is described which is capable of retrieving a simultaneous series of water samples at predetermined points above the sediment/water interface. This device has been successfully used in a study of the Tawe estuary, where a bottom layer of highturbidity, low-salinity water has been discovered.
The fatty acid composition of the leatherback turtleDermochelys coriaceaand its jellyfish prey
Authors: Holland D. L. , Davenport J. , East J.
Published: May 2009

The leatherback turtle,Dermochelys coriacea(L.) studied was a male, weighing 916 kg, with a total dorsal length of 291 cm. It was beached on the Welsh coast, UK in September 1988 and is currently the largest leatherback ever recorded.

Total lipid formed between 87.5 and 95.4% of the dry weight of representative samples of the blubber and 43.0% and 4.9% of the liver and pectoral muscle respectively. High levels of neutral lipid in the liver (79.0% of the total lipid) as well as the blubber (87.6–99.9% of the total lipid) suggest an important energy storage function for these tissues.

Overall, with the notable exception of 22:lwll, fatty acids which are found in a putative jellyfish diet ofRhizostoma, Amelia, CyaneaandChrysaoraare also present in the leatherback liver and muscle, blubber and other fatty tissues. Fatty acid 22:lwll is present in the jellyfish samples, but is absent or at trace levels only in the leatherback tissues (0.1–0.3% of the total fatty acids).

The polyunsaturated fatty acids of the w3 series 20:5w3, 22:5w3 and 22:6w3 are well represented in leatherback adipose tissues, muscle and liver as well as in the jellyfish examined. The leatherback and jellyfish lipids are therefore marine in character, but are also similar to terrestrial animal lipid in having a high proportion of fatty acids of the w6 series, principally arachidonic acid, 20:4w6. The significant levels of 20:4w6 in jellyfish total lipid (9.7–20.0% of the total fatty acids) and in the leatherback neutral lipid (1.0–10.9% of the total fatty acids) and phospholipid (0.6–15.5% of total fatty acids) fractions of all tissues sampled suggests that arachidonic acid assumes more importance in food chain relationships involving leatherbacks than in other marine food webs such as those involving fish.
Zinc and cadmium absorption in the symbiotic anemone Anemonia viridis and the non-symbiotic anemone Actinia equina
Authors: Harland A. D. , Bryan G. W. , Brown B. E.
Published: May 2009

Field and experimental observations on sea anemones (Actinaria) Ammonia viridis (Forskål) and Actinia equina (L.) indicated that in both species body zinc concentrations usually ranged between 100 and 200 ug (g dry wt)1 in waters containing up to 200 μg I1 of the metal. At higher dissolved concentrations, as observed in Restronguet Creek, A. equina exhibited only slightly enhanced tissue levels. However, in the laboratory, zinc levels in Anemonia viridis increased markedly at sea-water concentrations exceeding 200 μg I”1. Studies on the uptake of 65Zn-labelled zinc showed that, when the sea-water concentration was increased from 2 to 52 μg 11, both species absorbed the metal and new equilibria appeared to be reached in about a week. At equilibrium, the concentration of zinc in Actinia equina had risen by up to 11%, and in Anemon ia viridis, by up to 28%. About one third of the difference between the amounts absorbed by the two species may be accounted for by zinc accumulated in the symbiotic algae (zooxanthellae) of A. viridis. Short-term (12 h) experiments showed that, although A. viridis absorbed a significant amount of labelled zinc when the concentration increased from 2 to 52 μg I1, uptake was not much greater when the concentration increased from 2 to 202 μg I1. It is postulated that, up to a sea-water concentration of 202 μg I1, the absorption of zinc is dependent on the amount adsorbed at the body surface: saturation of the surface at higher concentrations leads to more direct dependence on the level of dissolved zinc.
Determinacy of fecundity in sole (Solea solea) from the Bristol Channel
Authors: Horwood J. W. , Walker M. Greer
Published: May 2009

Ovaries of the common sole (Solea solea (Linnaeus)) were collected prior to, or at the beginning of, spawning from the spawning grounds in the Bristol Channel. Size frequency distributions of oocytes over 100 μm are presented. They clearly show a break in the size frequency distributions, at about 170 μm, indicating that the production of new oocytes to be spawned that season had ceased. It indicates that the sole is a determinate spawner and that, at least for this population, an annual potential fecundity can be measured. Estimated annual fecundity at length of Bristol Channel sole is calculated, and values are compared with those found for sole from the North Sea, eastern English Channel and the Bay of Biscay.
On the breeding season of Lipophrys pholis (Pisces: Blenniidae) at Arrábida, Portugal
Authors: Almada Vitor C. , Barata Eduardo N. , Gonçalves Emanuel J. , De Oliveira Ruif
Published: May 2009

Direct observations of egg masses on the shore indicates that Lipophrys pholis is a winter and spring spawner in Portuguese waters. The results are compared with those published for the British Isles.

Lipophrys pholis, Linnaeus, 1758, is a very common intertidal fish in the north-eastern Atlantic and in the North Sea. Considerable work has been published concerning its breeding season in British waters (Lebour, 1927; Qasim, 1957; Shackley & King, 1977). The breeding season of the species at the southern limit of its range is almost unknown, and Zander (1986) mentions the period from April to August for the whole species. Based on dates of first appearance of larvae in plankton collected in the Bay of Biscay, Villegas (1981) concluded that breeding should have begun as early as the end of December.

In this report we present data on the spawning season of this blenny based on direct observation of the presence of eggs and/or parental guarding males on the shore.

Data were collected at a site located at Arrábida (38°28′N, 8°59′W), near Senibal, 50 km south of Lisbon, Portugal. In the course of behavioural observations on the breeding males of L. pholis, the area was visited at various intervals during the period 1986 to 1989. The nests were located intertidally in holes in vertical walls. On each visit, the presence of eggs and/or black males inside the nests was registered. Each nest was mapped for inspection in subsequent visits. The results are summarized in Figure 1.

It is clear that in our study area breeding begins as early as December, and has virtually ended in June.
Membranipora Arborescens (Bryozoa: Cheilostomida): a New Record in the Bay of Biscay
Authors: Alvarez Juan A.
Published: May 2009

One species of the cheilostome family Membraniporidae Busk is recorded for the first time in the Bay of Biscay. Observations were made on a dead fragment of Membranipora arborescens (Canu & Bassler), previously known in the Atlantic littoral of America (from the Cape Hatteras to Brazil), in the eastern Pacific (from Mexico to Equador) and in the coasts of western Africa.
Evidence for thermal stability of ribosomal DNA sequences in hydrothermal-vent organisms
Authors: Dixon D. R. , Simpson-White R. , Dixon L. R. J.
Published: May 2009

This paper reports the results of experiments designed to investigate the relationship between thermal stability of DNA and the physical and chemical conditions experienced by various species of invertebrates, with particular reference to hydrothermal vent organisms. The major conclusion is that thermal stability correlates positively with environmental temperature within the DNA regions encoding ribosomal RNA, but not throughout the genome. Increased thermal stability (based it is supposed on an increase in G-C content) of rDNA relative to total DNA confers protection to coding sequences which would otherwise be susceptible to damage during transcription. An increase in G-C content of rDNA will lead to an increase in G-C levels in rRNA which forms a major structural component of ribosomes, thus conferring increased thermal and chemical stability to these sites of amino acid synthesis within the cell.
Development of superficial and lateral line neuromasts in larvae and juveniles of plaice (Pleuronectes platessa) and sole (Solea solea)
Authors: Harvey R. , Blaxter J. H. S. , Hoyt R. D.
Published: May 2009

The distribution, morphology and sensory cell polarity of neuromasts were followed in developing larvae and recently settled juveniles of Dover sole (Solea soled) and plaice (Pleuronectes platessa) using scanning electron microscopy. In plaice the number of neuromasts increased at a similar rate on both sides of the fish throughout development, and most head neuromasts became incorporated into canals. On the trunk presumptive canal neuromasts were outnumbered by accessory superficial neuromasts in early juveniles. In sole the number of neuromasts increased at a similar rate on both sides until the start of metamorphosis. Subsequently a proliferation of superficial neuromasts on the abocular side of the head resulted in 80% of all the neuromasts on this side of the fish being located on the head in early juveniles. Both species had developed asymmetry of the head canals by the early juvenile stage, while canal formation on the trunk commenced later on the abocular side than on the ocular side. Mean numbers of sensory hair cells per neuromast showed little change until metamorphosis in both species, after which there was a two- to three-fold increase in hair cell number. The polarities of the sensory hair cells showed more variability on the head than on the trunk in both species. In general, hair cells were aligned for maximum sensitivity along the axes of the canals which would subsequently enclose them, but in the case of the superficial neuromasts on the abocular side of the head in sole the polarities followed surface features such as the nares, papillae and fin rays.
Rhizogeton Nudum (Cnidaria: Hydroida) in the British Isles
Authors: Jones D.
Published: May 2009

Specimens of a hydroid species previously unrecorded in Britain have been found during the course of a long-term study of the coelenterate fauna of an intertidal mussel bed in Morecambe Bay, Lancashire. Specimens were sent for examination to Professor J. Bouillon who indentified them as Rhizogeton nudum Broch.

The location and nature of the mussel bed, and the survey technique, have been described elsewhere (Jones & Miller, 1966; Jones & Clare, 1977; Jones, 1987). Rhizogeton nudum was observed in April and May 1987–91 and March 1989, on boulders where it was invariably associated with Clava multicomis (Forskal) and, more commonly, on mussel shells attached to these boulders. The few colonies recorded on boulders may have spread by stolon growth from attached shells.
The Life Cycle and Population Dynamics of Idotea Pelagica and I. Granulosa (Isopoda: Valvifera) In South-East Ireland
Authors: Healy Brenda , O'Neill Michael
Published: May 2009

Populations of Idotea pelagica and Idotea granulosa were studied monthly at Carnsore Point, County Wexford, from July 1978 to October 1979. The density of I. pelagica in mussel beds varied between 26 and 180/100 cm, reaching a peak in June. Numbers of I. granulosa in samples of Gigartina stellata fluctuated from month to month and averaged 200/100 g dry weight of algae. Peak densities were recorded in September of both years. Both species exhibited continuous growth, and breeding occurred throughout the year but with a main breeding period starting in winter. I. pelagica grew more rapidly and had an extensive breeding period lasting from December to August with two generations, some members of both generations producing second broods. For I. granulosa, the main breeding period was January to April, after which most adults died. Some of their offspring reached maturity in late summer giving rise to a lesser breeding peak in late summer and autumn but most did not mature until winter. Summer breeders of both species were smaller than those breeding in winter. The breeding cycles are compared with those of other populations in Britain and the Baltic and the possible reasons for the differences discussed.
Complemental Male in the Primitive Balanomorph Barnacle, Chionelasmus Darwini
Authors: Hui E. , Moyse J.
Published: May 2009

A complemental male was found on a solitary specimen of the primitive sessile barnacle Chionelasmus darwini. It was located on the scutal apex of the hermaphrodite and accommodated by a notch in the tergum. Its resemblance to complemental males of Bathylasma adds weight to the classification of the genus in the family Pachylasmidae rather than the Catophragmidae. Phylogenetic implications are discussed.
Seasonal Growth Studies of Intertidal Gastropods From Shell Micro-Growth Band Measurements, Including A Comparison With Alternative Methods
Authors: Ekaratne S. U. K. , Crisp D. J.
Published: May 2009

Tidal micro-growth bands were used to study the annual cycle of shell growth of individuals dated predominantly by the immersion mark technique, in three common intertidal gastropodsNucella lapillus(L.),Littorina littorea(L.) andPatella vulgataL. growing naturally in the Menai Straits. Growth in all three species approximated to the von Bertalanaffy type. All three species grew throughout the year,N. lapillusandL. littoreawith early autumn and summer maxima, respectively, andP. vulgatawith two maxima, one in late spring and the other in early autumn.P. vulgataalone were observed during exposure to a 6-day period of sub-zero air temperature in January 1982 when shell growth was totally interrupted. InNucellaandLittorinashell growth was found to be closely related to ambient temperature but inPatellathere was a summer depression in growth. The file technique when combined with the immersion mark technique in date marking, was found to be inferior to the immersion mark technique on its own, since filing occasionally affected growth adversely.

From among the factors determining the seasonal changes in growth rate, temperature was of major importance. Seasonal reproduction may also have an influence, especially inP. vulgatawhere gametogenesis coincides with the depression in growth rate during summer months.

Alternative methods used in gastropod growth studies were compared. In the light of inadequacies associated with other methods of measuring growth, micro-growth band measurements in gastropods offers a new method with high resolution suitable both for short and long-term growth studies. It has potential also for ecological and physiological aspects of growth measurements.
The Chromosome Complement of Procerodes Dohrni (Tricladida: Maricola)
Authors: Galleni Lodovico , Nigro Marco , Puccinelli Ileana
Published: May 2009

A karyometric analysis of the diploid complement of Procerodes dohrni (Turbellaria: Tricladida) was carried out on mitoses from regenerative blastema. P. dohrni has seven pairs of homologous chromosomes. Chromosome lengths decrease gradually and homologous pairs cannot be grouped. With reference to centromere position, chromosomes 1, 2, 3, 4 and 6 are metacentric, their centrometric indices vary from 46·74 to 39·82, while chromosomes 5 and 7 are submetacentric, their centromeric index being 34·63 and 29·86 respectively.
Feeding Habits of Some Young Fish
Authors: Lebour Marie V.
Published: May 2009

During the year 1918 several young fish brought in alive from the tow-nets were kept in small aërated aquaria at an even temperature and fed on plankton. In this way feeding habits were noted and some post-larval fish went through a metamorphosis into the adult form, notably Labrus bergylta the Ballan Wrasse, Solea vulgaris the Sole, Solea lascaris the Lemon Sole, and three species of Lepadogaster. Young Whiting and Pollack were also kept alive for some months and fed eagerly on most of the food that was given to them.
Diel bioluminescence in heterotrophic and photosynthetic marine dinoflagellates in an Arctic fjord
Authors: Lapota David , Young David K. , Bernstein Stephen A. , Geiger Mark L. , Huddell Howard D. , Case James F.
Published: May 2009

Oceanic and coastal bioluminescence in surface waters, in many instances, is produced by microscopic dinoflagellates. Their light emission is usually observed at a maximum during the night hours and markedly inhibited during the day. This diel periodicity has never been observed in situ for identified species and never before in heterotrophic Protoperidinium dinoflagellates. Pronounced differences in stimulable bioluminescence measured with bathyphotometers in Vestfjord, Norway in September 1990 correlated with simultaneous ship-board laboratory experiments. Cells of both the photosynthetic Ceratium fusus and heterotrophic Protoperidinium curtipes showed a pronounced inhibition of bioluminescence during the day and maximum bioluminescence at night.
Reproductive biology of the holothurian Holothuria forskali (Echinodermata)
Authors: Tuwo Ambo , Conand Chantal
Published: May 2009

The aspidochirote Holothuria forskali is a large common species found in the Atlantic and the Mediterranean. Its reproductive cycle has been determined in a population from Brittany using histological observations of the different classes of gonadal tubules, oocyte size frequencies and evolution of gonad indices. The cycle is annual and synchronous in both sexes. The different phases are well marked and are characterized by a long maturation during summer and autumn followed by a pre-spawning period during winter. Spawning is probably related to the increase in temperature. Most of the mature gametes are released. The resorption of the relict and spent tubules continues during the onset of the next vitellogenesis in the secondary tubules, without a rest period. The reproductive effort, documented from the gonad indices, is very high in this population which is composed of adult individuals.
The encapsular developmental sequence of the mesogastropod Turritella communis (Gastropoda: Turritellidae)
Authors: Kennedy J. J. , Keegan B. F.
Published: May 2009

The development of the lecithotrophic encapsulated larva of the internally-fertilizing, sublittoral gastropod Turritella communis Risso 1826 was documented using scanning electron microscopy and light microscopy. Encapsulated development was completed in 12 days at 15°C in the laboratory. Spawning occurred above ~10°C. Spawn masses consisted of numerous gelatinous egg capsules, each of which contained ~28 eggs, encased in albumen and fertilizing sperm. The eggs had an average diameter of 139 μm. Fertilization was accomplished by unpaired eupyrene sperm and occurred at the germinal vesicle stage. The developmental sequence followed the typical gastropod pattern, but was unique in a number of respects. Polar lobes were produced during meiotic maturation and early cleavage, with an especially large lobe occurring in association with the first cleavage, which was unequal. The blastula developed into a dorso-ventrally flattened placula at the 70-cell stage. Gastrulation occurred through invagination and epiboly acting together, and was uniquely accompanied by the development of ectodermal microvilli measuring ~ 1 μm in length. Extra-embryonic albumen began to be depleted after the development of the microvilli. It is proposed that the ciliated telotrochal cells gave rise to the pair of statocysts. Torsion was additionally observed to be facilitated by the growth of pre-mantle tissue on the right side and retardation of growth on the left side.
Biological observations on young scallops,Pecten maximus
Authors: Minchin Dan
Published: May 2009

The biology of young scallopsPecten maximus(Mollusca: Bivalvia) was examined using SCUBA diving. Within shallow and sheltered bays settlement took place near adult populations. Surfaces to which scallops attached were generally free of silt; these included algae, invertebrate tests and inorganic materials. Detachment could take place amongst individuals of 1 mm; however, in sheltered bays most remained attached until 4–13 mm. Following detachment scallops recessed in sediment. They were subject to dispersal by water turbulence and swimming induced by sea-stars. There was evidence to suggest high mortality from crab and sea-star predation during the summer and autumn.
Cephalopods from the stomachs of a Risso's dolphin (Grampus griseus) from the Mediterranean
Authors: Würtz M. , Poggi R. , Clarke Malcolm R.
Published: May 2009

Cephalopod remains from the stomachs of a Risso's dolphin (Grampus griseus Cuvier, 1812, Cetacea) entangled in a fishing net off the Ligurian coast (central Mediterranean Sea) include squids Ancistroteuthis lichtensteini, Histioteuthis bonnellii, H. reversa and Todarodes sagittatus and the sepiolid Heteroteuthis dispar. All these cephalopods live in oceanic water including water over the steep continental slope where Risso's dolphin is frequently sighted. Histioteuthis reversa contributed 78% of the cephalopods by number, 81% of the wet weight and 73% of the dry weight and calorific value. The total calorific value of the cephalopods represented by lower beaks was 17,300 kj.
Distribution and position maintenance behaviour of the estuarine mysid Neomysis integer
Authors: Hough A. R. , Naylor E.
Published: May 2009

The distribution of Neomysis integer (Crustacea: Mysidacea) in a tidally mixed estuary was found to be concentrated in mid-estuary with animals extending, primarily in summer, further up and down estuary. Within this range there were distinct intra-specific differences in distribution, with males occurring more commonly down-estuary and ovigerous females and juveniles up-estuary. Examination of tidal abundances in mid-channel showed males to be more abundant on the ebb tide, corresponding with their more downstream distribution, and all other individuals to be present mainly on flood tides, which would maintain the species within the estuary. Endogenous circa-tidal swimming activity in this species was found to be phased after the time of expected high tide, which would suggest ebb tide swimming in the estuary. More detailed examination of the distribution of Neomysis across the width of the estuary showed greatest concentrations of animals in slow-flowing water at the edge of the channel during the ebb tide. The endogenous swimming rhythm may therefore act to prevent stranding of animals intertidally during the ebb tide, while maintenance of position along the estuary appears to be by flood tide swimming under exogenous control.
The status of the genus Prayoides (Siphonophora: Prayidae)
Authors: Pugh P. R.
Published: May 2009

The status of the prayine siphonophore genus Prayoides, monotypic for the species Prayoides intermedia Leloup, 1934, is reviewed in the light of recent collections made by the submersibles ‘Johnson-Sea-Link’ I and II. It is concluded that the genus is not valid, and that the species name should be reduced to that of a junior synonym of a Praya species. The bracts of the two Praya species, P. dubia (Quoy & Gaimard (1833) 1834) and P. reticulata (Bigelow, 1911) are re-described, as in the past there has been much confusion as to their true identity.
A New Mesopelagic Appendicularian: Oikopleura Villafrancae sp. nov.
Authors: Fenaux R.
Published: May 2009

A new species, Oikopleura villafrancae, from the family Oikopleuridae (Lohmann 1915), subfamily Oikopleurinae (Lohmann 1896), genus Oikopleura (Mertens 1830), is described from numerous specimens collected at mesopelagic depth (360–880 m) during two different cruises: Migragel II (May 1988) and Medapp (May 1990) in the Ligurian Sea (northwest Mediterranean) between Villefranche-sur-Mer (French Riviera) and Corsica, respectively by the ‘Cyana’ and ‘Johnson-Sea-Link’ manned submersibles.
Latitudinal Displacements of the Gulf Stream and the Abundance of Plankton in the North-East Atlantic
Authors: Taylor A. H. , Colebrook J. M. , Stephens J. A. , Baker N. G.
Published: May 2009

An earlier time-series of the annual mean latitude of the north wall of the Gulf Stream is updated to give a series of values from 1966 to 1990. The trend is similar to those seen in plankton from the Continuous Plankton Recorder Survey around the British Isles. This connection may reflect the displacement of storm tracks across the North Atlantic.
The Size Of Mature Plaice, Turbot, And Brill, On Different Fishing Grounds
Authors: Cunningham J. T.
Published: May 2009

In the previous number of the Journal, I described my reasons for doubting whether the conclusions drawn by Mr. Holt, concerning the size at which plaice become mature, would hold good for the whole of the North Sea; and also whether the evidence he relied upon, in distinguishing mature and immature plaice, was sufficient. I stated that, as an actual fact, one sample of mature plaice, which were much below the limits of size determined by Mr. Holt, had come into my hands. I suggested, as a probability, that the presence of dead degenerating eggs in the tissue of the ovary was a proof that the fish had spawned, was a spent, and therefore a mature specimen. My words were: “It cannot be asserted as a certainty that these granular masses never occur in an immature ovary; to settle the doubt it will be necessary to make a careful examination of plaice in November and December, when all fish which are about to spawn will have a large amount of yolk in the eggs, and all fish in which the eggs are transparent and yolkless must be immature.” It was already known that these degenerating eggs do occur in spent ovaries, from which the ripe eggs have recently been discharged, and which bear evidence of the fact in their somewhat large size, flaccid and collapsed condition, and usually in the presence of a few detached ripe eggs in their interior.
Proposed Restrictions on the Landing of Undersized Plaice, in the Light of the New Evidence
Authors: Cunningham J. T.
Published: May 2009

Before the Parliamentary Committee, which conducted an inquiry in 1893, the trawling industry of Lowestoft, as represented by Mr. J. W. Hame, strongly opposed any restrictions being enforced as to the size of fish landed. One of the reasons given was that restriction was unnecessary, because small fish, especially plaice, were not landed at that port. Mr. Hame told the Committee that the day before he gave his evidence, namely, on May 10th, he turned out two boxes of plaice caught towards the Dutch coast, perhaps from 30 to 40 miles off that coast. He said that one box contained 110 fish, the smallest 12 in. long, and the other contained 90 fish, the smallest 13 in. long. These statements are quite at variance with my observations made at Lowestoft, during September and October this year, and I cannot help thinking that Mr. Hame was mistaken as to the grounds from which the fish came, or else was not sufficiently accurate in his numbers and measurements. The facts show that, on the one hand, a size-limit of 8 in. for plaice, as proposed by the Parliamentary Committee, would make no appreciable difference to the deep-sea trawling industry at Lowestoft, and, on the other hand, that higher limits, such as that which was proposed by Mr. Holt for the protection of the German grounds, would affect that port very seriously.
A Carcinus with a right-handed walking-leg on the left side of the abdomen
Authors: Bethe Albrecht
Published: May 2009

Amongst a great number of crabs collected in Plymouth Sound for my studies of the central nervous system, one specimen was found with a very interesting abnormality. The thorax of the crab—a female—is normal. The length of the carapace is 47 mm., the breadth 64 mm. The claws and legs are in the right positions, and of normal proportions, with the exception of the fourth leg on the left side, which is smaller than usual. In my opinion, this leg was broken some time before the crab came in, and was not yet quite regenerated. The first four segments of the abdomen are also normal. Each has a couple of pedes spurii. To the fifth segment, which in the crab is always legless, a large leg is fastened on the left side. (Fig. 1.)
Note on Projects for the Improvement of Sponge-Fisheries
Authors: Bidder George
Published: May 2009

In considering the experiments of Buccich (6) on propagation of sponges by cuttings, two main questions present themselves:—

(1) If a sponge be divided into many fragments, will the total increase of such fragments and their progeny be greater than the increase of the intact sponge and its progeny would have been in the same time; the conditions of water, &c., being identical?

(2) Are sponges, grown as recommended by Buccich, more or less favourably situated than those on the sea-bottom?
Littoral Distributions and Evidence For Differential Post-Settlement Selection of the Morphs of Actinia Equina
Authors: Quicke D. L. J. , Donoghue A. M. , Keeling T. F. , Brace R. C.
Published: May 2009

Examination of the intertidal distributions of isozyme and pedal colour phenotypes of Actinia equina L. has shown that anemones displaying column coloration ranging from red to brown, are divisible into three, ecologically distinct forms in Britain, which we currently interpret as being morphs of a single species. These are termed the upper (U), mid (M) and lower (L) shore morphs, which are relatively most abundant on the upper mid, lower mid and low shores, respectively; not all morphs are represented on some shores. The U, M and L morphs may be separated on the basis of their hexokinase and malate dehydrogenase phenotypes. The U morph is homozygous slow and fast respectively, the L morph is slow and fast respectively whilst the M morph is heterozygous at both loci. Data on linkage of pedal disc colour and alleles at a tetrazolium oxidase locus, and of an association between alleles at the hexokinase locus and those at an esterase locus, are given.
Further Analysis of Individual Spacing within Aggregations of the Anemone, Actinia Equina
Authors: Brace R. C. , Quicke D. L. J.
Published: May 2009

We have recently assessed phenotypic and genotypic diversity within an aggregation of the intertidal beadlet anemone, Actinia equina L., located at Burniston in N. Yorkshire, on the east coast of Britain (Quicke & Brace, 1983). The study was undertaken in order to provide information relating to the role of intraspecific aggression (Bonnin, 1964; Brace & Pavey, 1978; Brace, Pavey & Quicke, 1979) in modifying the spacing of individuals. Limited work on the genus Actinia (A. tenebrosa Farquhar) has already indicated that whilst genetically dissimilar anemones display aggression towards one another, auto-genotypic aggression is minimal (Ayre, 1982), as is also the case for the clonal anemone, Anthopleura elegantissima (Brandt) (Francis, 1973a,b,1976). We therefore anticipated that aggressive interactions would promote auto-genotypic clustering, initiated by the local settlement of the asexually produced, brooded young (Carter & Thorp, 1979; Gashout & Ormond, 1979; Orr, Thorpe & Carter, 1982), and that correspondingly, genetic diversity within aggregations of anemones would be low.
Production of Mussels, Mytilus Edulis, in Suspended Culture and Estimates of Carbon and Nitrogen Flow: Killary Harbour, Ireland
Authors: Rodhouse P. G. , Roden C. M. , Hensey M. P. , Ryan T. H.
Published: May 2009

Culture of mussels, Mytilus edulis L. is a developing industry in Irish coastal waters. Settling larvae are collected on 10 m long ropes which are suspended from g.r.p. rafts at a density of five ropes per square metre or from paired long lines, buoyed by plastic floats, at a density of some four hundred ropes per hundred metres. Mussels are harvested after eighteen months when the ropes yield up to 5 kg live weight per metre or approximately 250 kg m−2. Commercial culture at this density clearly exerts a considerable effect on energy and nutrient flow in the coastal ecosystem. In order to quantify the role of cultured mussels we investigated the carbon and nitrogen budget for production rafts and long lines in Killary Harbour, a fjordic inlet on the Irish west coast (Rodhouse et al. 1984) and compared these with estimates for the wild population on the shore.
Interrelationships of Cholesterol and Hydrocarbon Metabolism in the Shore Crab,Carcinus
Authors: O'Hara S. C. M. , Neal A. C. , Corner E. D. S. , Pulsford A. L.
Published: May 2009

In marine crustaceans the polynuclear aromatic hydrocarbon benzo[a]pyrene undergoes changes mediated by benzo[a]pyrene mono-oxygenase (BPM), a cytochrome P-450 dependent enzyme system requiring molecular oxygen and NADPH as a cofactor: it has now been detected in several species (see O'Haraet al.1982).
The Growth, Abundance and Diet of O-Group Sea Bass,Dicentrarchus Labrax, From the Severn Estuary
Authors: Aprahamian Miran W. , Barr Christine Dickson
Published: May 2009

Eggs ofDicentrarchus labrax(L.) have been collected from the mouth of rivers or inshore waters of salinity greater than 30 p.p.t. (Barnabé, 1978; Kennedy & Fitzmaurice, 1972). The main spawning period is between April and June (Kelley, 1979; Kennedy & Fitzmaurice, 1968), though ripe males have been reported as early as February and as late as mid-July (Kennedy & Fitzmaurice, 1972). The fertilised eggs 1·15—1·51 mm in diameter, are pelagic, take between two and five days to hatch and the prolarvae are 3·25—4·05 mm in length when they emerge (Barnabé, 1976; Bertolini, 1933, pp. 310–331; Lumare & Villani, 1973; Jackman, 1954). Postlarval stages have been recorded from the Bristol Channel in mid-June and mid-July (Russell, 1980) as well as off Plymouth between mid-March and mid-July (Russell, 1935, 1976; Russell & Demir, 1971). Although a few juveniles have been encountered, from the middle and lower reaches of estuaries, during their first summer (Kennedy & Fitzmaurice, 1972), it is not until the autumn/winter that relatively large numbers of o + bass have been reported from British estuaries (Claridge & Potter, 1983; Hardisty & Huggins, 1975; Hartley, 1940; Murie, 1903; Van den Broek, 1977; Wheeler, 1979). Juvenile bass have also been recorded from lagoons and coastal waters, during their first summer, indicating that these are important nursery areas (Arias, 1980; Barnabé, 1978; Chervinski & Lourie, 1972; Ferrari & Chieregato, 1981; Gandolfi, Rossi & Tongiorgi, 1981).
The Autecology of Cyathura Carinata (Crustacea: Isopoda) in a Cooling Water Discharge Lagoon
Authors: Bamber R. N.
Published: May 2009

Cyathura is a genus of Anthurid isopods represented by some fourteen estuarine species around the world (Miller & Burbanck, 1961). They are unusual amongst the isopods in that the majority of individuals in a population show protogynous hermaphroditism, adults breeding as females in their first year, then changing to males over the following winter (Legrand & Juchault, 1963; Burbanck & Burbanck, 1974). The adults are tubicolous, virtually incapable of swimming, and have limited mobility, resulting in disjunct, stable populations, some of which, in the case of C. polita (Stimpson), are known to have maintained the same locations and densities over a period of 20 years (Burbanck & Burbanck, 1975). The embryos develop within a marsupium or brood pouch on the thoracic somites of the female, and are released as interstitial juveniles 1 mm or more in length. With populations averaging 200 to 400 individuals per square metre, these animals are convenient for autecological studies. Indeed, Burbanck & Burbanck (1979) considered that as hardy, euryokous animals, consistent in their tolerance to fluctuating environmental conditions, and convenient for study, Cyathura species are ideal ‘indicator organisms’ in estuaries.
Fluorescence and the Light/Nutrient Interaction inMonochrysis
Authors: Droop M. R.
Published: May 2009

The observed diminution in photosynthetic efficiency upon vitamin B12limitation inMonochrysisindicates that nutrient limitation may profoundly influence the photosynthetic status of a natural population and must therefore be taken into account in productivity studies (Droopet al.1982). It also suggests that photosynthetic efficiency could be used as a criterion between nutrient and light control of growth in natural populations. However, measurement of photosynthetic efficiency is cumbersome under field conditions and it would be advantageous if some other associated variable more quickly measured, such as, e.g.in vivochlorophyllafluorescence, could be used as a reliable indicator.
The Life-Cycle and Population Dynamics of Streptosyllis Websteri (Polychaeta: Syllidae) from a Northumberland Beach
Authors: Garwood P. R.
Published: May 2009

The population of Streptosyllis websteri at Newton, Northumberland shows epigamous reproduction and has an extended spawning season from April to July, during which there are two main peaks of spawning activity. Most individuals spawn twice in the breeding season at the beginning of their third year of life, although some individuals may contribute to the second spawning peak of the breeding season at the beginning of their second year. Growth rates are remarkably uniform, and year classes are usually clearly distinguishable using setiger number frequency distributions. Observations on growth and mortality suggest that there is competition for resources amongst the new recruitment class over the first few months of life, but that overall survival through the first year is density independent and likely to be determined by external factors. Larval development is largely benthic, and it is unlikely that there is any prolonged truly pelagic larval phase.
Trade liberalisation and the nutrition transition: mapping the pathways for public health nutritionists
Authors: Thow Anne Marie
Published: May 2009

Objective

To describe pathways through which trade liberalisation affects the food environment, relevant to the nutrition transition, in order to enable public health nutritionists to understand trade policy as a macro-level influence on food consumption.

Design

The pathways mapped in the present paper are based on the agreements of the World Trade Organization, which shape national policy. Implications for nutrition are presented based on a comprehensive literature review, and case studies are used to illustrate the various pathways.

Setting

Developing countries are currently experiencing a nutrition transition, resulting in dietary patterns associated with chronic disease. Chronic diseases are amenable to prevention, and trade policy has been highlighted as a potential avenue for nutrition-related prevention.

Results

Trade liberalisation influences the food environment through facilitating trade in goods and services, enabling investment and decreasing support/protection for domestic industry. These policy outcomes facilitate the nutrition transition particularly through increasing the availability and affordability of processed foods and animal products. The framework highlights the complex relationship between trade policy and the nutrition transition, with both negative and positive outcomes arising from different aspects of trade liberalisation.

Conclusions

Policy change associated with trade liberalisation has created incentives for consumption patterns associated with the nutrition transition, but has also had some positive nutritional outcomes. As a result, it is important for public health nutritionists to consider the implications of trade policy decisions in their efforts to prevent and control diet-related chronic diseases.