bluuebunny/crossref_metadata_2025 huggingface dataset:
The Effects of Bottom Friction and Earth's Rotation on an Island's Wake
Authors: Pingree R. D. , Maddock Linda
Published: May 2009

Whilst there have been a number of fundamental studies illustrating the effects of Earth's rotation on the flow around submerged obstacles (Hogg, 1973) and islands (Longuet-Higgins, 1969) there appear to be relatively few studies that include both non-linear advective and frictional effects (Huthnance, 1972), and few were found describing the stagnation region that develops in the lee of the flow due to the advection of vorticity generated by the frictional stress associated with a beach gradient (Pingree & Maddock, 1979). In this paper some rotational flow patterns that can develop around an island due to these effects are examined using a numerical model and an overall attempt has been made to illustrate the possible use of numerical models as a tool for theoretical investigations in areas of study that until recently have been exclusively analytical or experimental. An island is surrounded by a uniform beach gradient and the model illustrates how varying bottom topography modifies a steady flow due to both frictional and Earth's rotation effects. Only non-oscillating flows with steady wakes are considered here so that the vorticity sources and sinks can be examined as simply as possible. Stagnation regions due to frictional effects are known to be important in determining sediment deposition and the effects of the Earth's rotation may result in increasing asymmetry in sediment distributions (Johnson, Vogt & Schneider, 1971).
Turrisphaera Polybotrys sp. nov. (Prymnesiophyceae) from West Greenland
Authors: Thomsen Helge Abildhauge
Published: May 2009

The genus Turrisphaera Manton, Sutherland & Oates was described on the basis of material from West Greenland, Resolute Bay and South Alaska (Manton, Sutherland & Oates, 1976). In addition to these localities the genus has later been recorded from New Zealand (Moestrup, 1979) and Denmark (Thomsen, unpublished results). The diagnostic characteristics of the genus are the tower-shaped coccoliths and the small hexagonal crystallites. The two species described, the generic type T. borealis Manton, Sutherland & Oates and T. arctica Manton, Sutherland & Oates (Manton et al. 1976), were distinguished by the mucilage covering of T. arctica, and by a certain difference in the elaboration of the distal part of the coccoliths. Furthermore, in T. arctica the flagellar pole coccoliths were longer than the coccoliths elsewhere on the cell (all coccoliths appear equal in T. borealis), and the crystallites somewhat smaller than those of T. borealis.
Taxonomic Descriptions of Some Conspicuous Species of Strobilidiine Ciliates (Ciliophora: Choreotrichida) from the Isles of Shoals, Gulf of Maine
Authors: Lynn D. H. , Montagnes D. J. S.
Published: May 2009

The marine plankton contains an extremely diverse assemblage of ciliates which may be important in planktonic energy flow (e.g. see Burkill et al. 1987; Porter et al. 1985; Rassoulzadegan & Sheldon, 1986; Sherr & Sherr, 1987; Stoecker, Michaels & Davis, 1987; Verity, 1987). Many marine ciliates are delicate in nature and until recently have been poorly collected. Thus, they are often entirely missed in plankton sampling. During an investigation of the role of planktonic ciliates at the Isles of Shoals, Gulf of Maine (Montagnes & Lynn, 1988; Montagnes, Lynn, Roff & Taylor, 1988) samples were Bouin-fixed to preserve these delicate species. The ciliates were subsequently quantitatively protargol silver-stained to estimate species abundances and biomass (Montagnes & Lynn, 1987). This staining method, in addition to providing quantitative estimates of abundance and cell volume, gives invaluable taxonomic information by revealing cellular structures. Thus, it has been possible to compare the ciliates from the Gulf of Maine with described species.
Illustrated Key toAmpeliscaSpecies from the North-Eastern Atlantic
Authors: Dauvin Jean-Claude , Bellan-Santini Denise
Published: May 2009

The genusAmpeliscacomprises more than 150 species and is one of the more important benthic genus of marine amphipods. New species are regularly added (Barnard & Agard 1986; Bellan-Santini & Marques, 1986; Goeke, 1987).Ampeliscaare found from the intertidal zone to abyssal depths but most of them live on the continental shelf. In spite of many studies, it is often difficult to distinguish some species which are morphologically similar. In the last ten years, twenty-two species have been described from the north-eastern Atlantic (BellanSantini & Kaïm-Malka, 1977; Bellan-Santini & Dauvin, 1981, 1986; Dauvin & Bellan-Santini, 1982, 1985; Bellan-Santini & Marques, 1986). Materials come from MNHN of Paris collection, collected by Chevreux (1894–1924) (Dauvin & Bellan-Santini, 1985, 1986) and specimens collected during the last 25 years. All these new species are described from the Atlantic coast from northern Brittany to the Sahara and from the Mediterranean Sea.
In Situ Observations of Deepwater Medusae in the Genus Deepstaria, with a Description of D. Reticulum, Sp. Nov.
Authors: Larson R. J. , Madin L. P. , Harbison G. R.
Published: May 2009

Medusae are common constituents of the meso-and bathypelagic fauna. Small, transparent trachyline hydromedusae are usually most abundant, but the larger (2–10 cm diameter) pigmented coronate scyphomedusae are often collected in trawl nets (Thurston, 1977; Roe, James & Thurston, 1984; Larson, 1986) or observed from submersibles (Mackie & Mills, 1983; Mackie, 1985; Larson, Madin & Harbison, unpublished observations). Larger (30–70 cm) deep-sea semaeostome scyphomedusae are only infrequently collected in nets (Harbison, Smith & Backus, 1973; Larson, 1986), and would appear to be the rarest forms. For example, Thurston (1977) collected over 16000 midwater medusae in trawls yet he did not report taking a single mesopelagic semaeostome. However, recent investigations using submersibles have shown that these medusae are much more common than net hauls alone would suggest (Smith, 1982).
Cysts and Sediments: Gonyaulax Polyedra (Lingulodinium Machaerophorum) in Loch Creran
Authors: Lewis Jane
Published: May 2009

The distribution of dinoflagellate cysts in sediments is a subject of increasing interest. There have been several approaches, of which two are relevant to this investigation. The studies of palynologists who endeavour to relate the distribution of cyst assemblages to environmental factors (for example Reid, 1972; Wall et al. 1977; Harland, 1983) and the studies of phycologists, concerned with toxic dinoflagellate blooms, who concentrate on the distributions of cysts of bloom species (for example Anderson, Kulis et al. 1982; Thayer et al. 1983). Consequently an increasing amount of information on quantitative distribution of cysts has become available. In 1976 Dale reported the investigation of sediments from Trondheimsfjord, relating the abundance of cysts to the percentage abundance of finer sediment. Wall et al. (1977) provided a more comprehensive picture of this relationship showing that cyst density (numbers of cysts per gram dry weight of sediment) increased logarithmically with increased percentage of the silt plus clay mineral fraction to a level where this comprised 50–60% of the sediment, after this no further increase occurred.
Sex Change in the Female Dog-Whelk,Nucella Lapillus, Induced by Tributyltin from Antifouling Paints
Authors: Gibbs P. E. , Pascoe P. L. , Burt G. R.
Published: May 2009

Imposex, the development of a penis and vas deferens in the female (Smith, 1971) is known to occur in over 30 species of marine gastropods but, to date, in only one species has this syndrome been demonstrated to have a serious deleterious effect. This species is the dog-whelk,Nucella lapillusL. Both field and laboratory observations have provided conclusive evidence that imposex inN. lapillusis initiated by tributyltin (TBT), used as a biocide in antifouling paints, at concentrations in water of less than 1 ng Sn/1. This feature is manifest in the widespread occurrence of imposex even in areas far removed from centres of boating activity (see Bryanet al.1986). Imposex appears to have little effect on the reproductive biology ofN. lapillusuntil this syndrome is developed to its fullest extent when it sterilises the female because the pallial oviduct becomes occluded by vas deferens tissue thus preventing expulsion of the egg capsules (Gibbs & Bryan, 1986). Laboratory experiments have indicated that this condition, found in females close to harbours and marinas, may prevail after prolonged exposure during the first few years of life to TBT levels as low as 2 ng Sn/1 (Gibbset al.1987). Of six organotin compounds tested by Bryan, Gibbs & Burt (1988), tributyltin chloride proved the most effective in promoting imposex inN. lapillus.
Metamorphosis of Pectin Aria Koreni (Annelida: Polychaeta) and Recruitment of an Isolated Population in the English Channel
Authors: Lambert R. , Retière C. , Lagadeuc Y.
Published: May 2009

In the Bay of Seine (English Channel) the polychaete Pectinaria koreni exhibits interannual stability in its abundance, despite its isolated distribution and its bentho-planktonic life cycle. To test the hypothesis of a high level of recruitment related to high survival rate of the post-larvae due to metamorphosis in the water column (transformation of metatrochophore into aulophore), we undertook a study of the morphology and the dynamics of the aulophore stage during May and June 1987. The morphological study snowed that aulophore larvae do not possess all the morphological features needed for benthic life on their first contact with the substratum. Fifteen days are needed to complete this development, and during this time the mortality rate is high. The possible role of this delayed metamorphosis on the transport of aulophore larvae towards sites favourable to adults is also discussed.
The Annual Pattern of Condition and Maturity in Bass, Dicentrarchus Labrax, in Waters Around England and Wales
Authors: Pawson M.G. , Pickett G.D.
Published: May 2009

Morphometric data on bass, Dicentrarchus labrax L. (Pisces: Percoidei), sampled around the coasts of England and Wales between 1982 and 1990, have been analysed to elucidate seasonal patterns of feeding, body condition and gonad maturity. The somatic condition and fat reserves of bass in the Irish Sea and southern North Sea improved more rapidly during the spring and summer than in bass further to the south. In winter, however, fat reserves were higher and there was more food in the stomachs of bass caught in the western English Channel. The onset of maturity was related to fish length. Male bass became mature for the first time at 32–36 cm total length, but though many females showed signs of gonad growth at this size, no female <42 cm was found with mature (ripe or spent) gonads. Gonad development in adult bass of both sexes began in October and, from January until June, most males >36 cm had ripe testes. The period during which ripe eggs could be expressed from the ovaries of female bass was briefer, with spawning apparently peaking in April. It is concluded that the migration of adult bass to the north in spring and southwards and westwards in autumn has both growth and reproductive benefits related to sea temperature, and that the more limited movements of bass <42 cm, which remain in relatively cold, inshore waters in winter, results in an inhibition of gonad maturity in females.
The Olfactory Epithelium in Plaice (Pleuronectes Platessa) And Sole (Solea Solea), Two Flatfishes With Contrasting Feeding Behaviour
Authors: Harvey Robin
Published: May 2009

The olfactory epithelium of developmental stages from yolk sac larvae to adults of plaice,Pleuronectes platessaL. (Pisces: Pleuronectidae) and Dover sole,Solea solea(L.) (Pisces: Soleidae) was examined using scanning electron microscopy (SEM). Two ciliated cell types and a microvillar cell are present in both species soon after hatching and persist into adulthood. In juveniles and adults of plaice, there were significantly higher densities of ciliated sensory cells in the eyed side of the fish than in the blind side over all regions of the olfactory lamellae. Densities of microvillar cells were an order of magnitude less than those of ciliated cells in regions on the wider part of the lamellae, with no significant difference between organs in most of these regions. On the narrow part of the lamellae, densities of microvillar cells were significantly higher than on the wide part, and significantly higher in the eyed side organ. In sole, ciliated cells were significantly more dense in the blind side organ in three of the four regions examined in this species. In contrast, microvillar cells showed a similar pattern to that in plaice, being significantly more dense in the eyed side organ in two of the four regions. Comparisons between the species showed significantly higher densities of both cell types in sole, microvillar cells being an order of magnitude denser in comparable regions on the lamellae. In addition, the total area of the olfactory lamellae is around three times greater in sole. These data point to a possible morphological basis for the enhanced olfactory capabilities of sole apparent from behavioural studies.
Marine Biodiversity: Causes and Consequences
Authors: Ormond R.F.G.
Published: May 2009

A meeting on Marine biodiversity: causes and consequences was held in York on 30 August – 2 September 1994, organized by the Marine Biological Association and the Scottish Association for Marine Science and supported by the World Wildlife Fund for Nature, the Natural History Museum and the Marine Conservation Society. The following 16 papers were first presented at this meeting.
Large-Scale Spatial Pattern of the Macrobenthic Diversity in the Eastern English Channel
Authors: Añorve-Sanvicente Laura , Leprêtre Alain , Davoult Dominique
Published: May 2009

A description is provided of the large-scale spatial distribution of the diversity of the benthic macrofauna in the eastern English Channel. Data from the oceanographic cruises of the RCP (Recherche Coopérative sur Programme) Benthos de la Manche Research Programme were obtained during the summers of 1971 to 1975. A total of 707 samples were analysed.

Diversity of each sample was measured by means of the species richness (i.e. the total number of species present), the Shannon-Weaver diversity index and Pielou's evenness index. Diversity values were plotted for all 707 oceanographic stations in the area, following a smoothing procedure. Large-scale spatial trends of diversity of the benthic macrofauna were analysed in relation to sediment and species assemblage distribution, but no spatial correlation was found between the two factors. These results indicate that mechanisms affecting large-scale spatial distribution of the diversity are different from those acting on a smaller scale. The role of the hydro-sedimentary processes acting at the geographic scale of the eastern English Channel as presumptive causes of this large-scale pattern of the macrobenthic diversity is discussed.
Species and Generic Gamma-Scale Diversity in Shallow-Water Marine Amphipoda with Particular Reference to the Mediterranean
Authors: Myers A.A.
Published: May 2009

Major hotspots of amphipod species richness and of species and generic endemicity can be recognized in shallow seas. Recognition of ‘hotspots’ for amphipods must take account of the species-area relationship but not of latitude. The richness and endemicity of amphipods in the Mediterranean Sea is shown to be high when compared with other shallow seas This indicates a long in situ evolutionary history and is therefore not compatible with the hypothesis that the Mediterranean fauna was extirpated in the late Miocene.
The Influence of The Introduced Tropical Alga Caulerpa Taxifolia, on the Biodiversity of the Mediterranean Marine Biota
Authors: Santini-Bellan D. , Arnaud P.M. , Bellan G. , Verlaque M.
Published: May 2009

The Mediterranean proliferation of Caulerpa taxifolia provides an opportunity to examine the extent to which an introduced species can modify biodiversity. During 1992, benthic invertebrates were sampled in Roquebrune-Cap Martin area, at depths of 6 and 10 m, from a Caulerpa station and a reference station. Species richness is slightly lower at 6 m within Caulerpa while the number of specimens is much reduced at both depths. Similarity indices compare well between reference and Caulerpa stations.

Caulerpa taxifolia, distributed in tropical seas, was recorded for the first time in the Mediterranean in 1984, as a single 1 m2 patch. This surface increased to 3 ha by 1990, 30 ha in 1991, 100 to 430 ha in 1992, and 1000 to 2000 ha at the end of 1993 (Meinesz & Hesse, 1991; Boudouresque & Meinesz, 1994).

Maximum colonization is between 2 and 6 m depth, but the alga has been observed down to 99 m. Density can reach 350 m of fronds and 14,000 leaves per m2. Caulerpa taxifolia colonizes any type of substrate and invasion results in a drastic impoverishment of the algal components of the communities (Boudouresque et al., 1992; Verlaque & Fritayre, 1994). According to these authors, maximal poverty of communities coincides with the maximal development of C. taxifolia (summer-autumn) and epiflora is negligible, except during spring.

These changes may induce functional and structural modifications of the fauna that lived in the communities before infestation. Invasion, particularly of photophilic algae and Posidonia beds (Ros et al., 1985), can modify quality and intensity of physical, chemical and hydrodynamical factors, number and quality of shelters, quantity and quality of food, and exchange of individuals between communities and populations.
Environmental and Endocrine Control of Reproduction in Two Species of Polychaete: Potential Bio-Indicators for Global Climate Change
Authors: Lawrence A.J.
Published: May 2009

An in vitro bioassay has been developed which shows that oogenesis in Harmothoe imbricata is controlled by a gonadotrophic hormone which promotes egg protein synthesis in developing oocytes. A similar endocrine control mechanism is found in Eulalia viridis and analysis of in vivo assays indicate that the hormone acts as a transducer between the environment and the gamete. The timing of gametogenesis is controlled by environmental cues in both species and may be affected by predicted global climate change. With the development of these sensitive hormone assays it is possible to test the impact of climate change on both species, providing a possible early warning system for global warming and potential bio-indicators of climate change. Harmothoe imbricata is likely to be the more sensitive indicator species.
The Distribution of Halacaridae (Acari: Prostigmata) Among Macroalgae on Sheltered Rocky Shores
Authors: Somerfield P.J. , Jeal F.
Published: May 2009

Clumps of macroalgae on sheltered shores exposed at low tide provide a mosaic of micro-habitats for halacarid mites. The predominant pattern is one of zonation, with the level of high water neap tides limiting the distribution of many species of Halacaridae. Within emersed clumps of macroalgae four micro-habitats are recognized: the dry surface layer of the clump; damp fronds within the clump retaining surface moisture; lower stipes and holdfasts; the surface of the substratum between the holdfasts. Halacaridae are spatially segregated, different species being associated with different micro-habitats within clumps. This has implications for the way in which intertidal phytal meiofaunal communities are sampled. In general damp fronds from within seaweed clumps are collected. Species characteristically associated with stipes, holdfasts and the substratum beneath the clumps are probably under-represented in the majority of collections, and may, therefore, be considered rare.
A Note Concerning Associates of the Scavenging Amphipod Orchomene Nanus (Lysianassoidea)
Authors: Moore P.G. , Wong Y.M.
Published: May 2009

The parasitic copepod Sphaeronella? callisomae, usually a single female, was occasionally found in the brood pouch of the amphipod Orchomene nanus. It is possible that this parasite consumes its host's eggs. Infected female hosts were significantly smaller than uninfected ones, so the copepod may retard host growth (or select young female hosts). Other associates (ciliates) were found in the body cavity and epizooitically on the host's gill lamellae.

Extensive collections of Orchomene nanus (Krøyer) (Crustacea: Amphipoda) have been made year-round (April 1993 to April 1994) using funnel-traps baited with crushed shore crabs (Carcinus maenas (L.)) deployed overnight (soak time 17 h) in the shallow sublittoral (5–6 m depth) at Keppel Bight, Millport (54°45·75′N 4°54·48′W: for further details, see Moore & Wong, 1995, in press a,b).

The presence of nicothoid copepods (tentatively identified by Mr M. O'Reilly, Clyde River Purification Board, as Sphaeronella? callisomae Scott; an inadequately described species, see Gotto, 1993) in the brood pouch of this amphipod were recorded routinely. At least two species of ciliates were also encountered. A sessile ciliate protozoan (?Lagenophrys sp.) occurred commonly as an epizoite of O. nanus branchiae (Figure 1A–D); and unidentified parasitic ciliates, possibly of three species, occurred in the body cavity (Figure 1E, F).

The incidence of parasitization of female O. nanus with S. ?callisomae was very low (0·81%; 8/990). There was only ever a single mature female copepod per host, although instances occurred of multiple infestations with nauplii or copepodites. Two female O. nanus were recorded with a female nicothoid coexisting with the amphipod's own eggs inside the brood pouch.
The Epifauna of the Northern North Sea (56°–61°N)
Authors: Basford D.J. , Eleftheriou A. , Raffaelli D.
Published: May 2009

More than 65% of the demersal fish and shellfish caught by British vessels are landed at Scottish ports, most of the catch being taken from waters north of 56°, i.e. in the northern North Sea. The major resource supporting these fisheries is the benthos, but the distributions of both infaunal and epifaunal benthic invertebrates in the North Sea are poorly documented. Moreover, the environmental factors determining the composition and structure of North Sea benthic assemblages are not well understood. There have been several limited surveys of the benthos (Stephen, 1934; Ursin, 1960), and recently Dyer et al. (1982, 1983), Cranmer (1985) and Cranmer et al. (1984) attempted a more quantitative and systematic survey. Various schemes have been proposed to explain observed regional differences in types of benthic assemblage, usually based on the biological characteristics of water masses, and / or a limited and fragmentary knowledge of the sediments of the North Sea {e.g. Glemarec, 1973; Dyer et al, 1983).
Mercury Concentrations in Fish From Contaminated Areas in Scottish Waters
Authors: Clark G. , Topping G.
Published: May 2009

The disposal of wastes to sea is regulated internationally by the Oslo and Paris Conventions, which were ratified by the United Kingdom in 1975 and 1978 respectively. Under these Conventions the direct disposal of certain substances, for example mercury and cadmium compounds, is prohibited, unless they are present in wastes as trace constituents. Of particular concern in the case of mercury is its possible incorporation in the aquatic food chain and transfer to man via marine foodstuffs. There are many examples of accumulation of mercury by fish in contaminated areas e.g. Liverpool Bay (Norton & Murray, 1983; Franklin, 1987); Haifa Bay (Hornung & Krumgalz, 1984); Minimata Bay (Fujiki, 1980) and in river systems such as the Ems (Essink, 1980,1988).
The Reproductive Organs of the Herring in Relation to Growth
Authors: Wynne-Edwards V. C.
Published: May 2009

From two series of samples of different populations of herrings from the neighbourhood of the Isle of Man, data were obtained of the lengths, weights, gonad-weights, and ages of 396 mature fishes. The growths of the whole body and of the gonads were represented by the upper portions of S-shaped curves. The male and female body-weights are nearly the same at any age over the range considered, but the testes of the male are always heavier than the ovaries of the female in such comparable fishes. The females attain a greater size than the males.

The weight of the gonads bears a linear relationship (as a first approximation) to the total weight of the fish over the range of size considered. The regression functions evaluated for the two sexes are

where y is the gonad-weight and x the total weight of the fish, both in grams. The difference between the weights of testes and ovaries in male and female fishes of the same size is therefore about 4·7 gm., which is shown to be significant. It cannot be due to specific gravity of growthrate differences, since the regression coefficient (0·26) is the same for both sexes.

It is suggested that the reproductive organs start to develop in the summer following the laying down of the first winter ring on the scales; and that the initial handicap in female gonad-weight may be due to the males being smaller than the females at this time.

Confirmation of the conclusions drawn from the Calf herring is given by a similar analysis of the Low herring samples.
Note on a Sailfish (Istiophorus Americanus Cuvier and Valenciennes) New to the British Fauna
Authors: Norman J. R.
Published: May 2009

About 9a.m. (flood tide) on 17th August,1928, a large sailfish was captured in a dying condition in the main channel of the Yealm estuary, South Devon, opposite the Yealm Hotel, about a mile above the Yealm Bar. The fish was carefully packed up by Mr. V. C. Wynne-Edwards, and promptly despatched to the British Museum (Natural History), where the plaster-cast shown in the accompanying illustration (Fig. 1) was prepared by Mr. S. Stammwitz. The specimen was then cut into two pieces and preserved in alcohol.

Owing to the difficulty of preserving these large fishes in museums, except as stuffed skins, and to the marked changes which they appear to exhibit at different stages of growth, our knowledge of the group which includes the swordfishes, sailfishes, and spearfishes is decidedly limited, and the identification of species is a matter of some difficulty.

In a recent monograph, Jordan and Evermann distinguish nine species of Istiophorus, of which five are said to be new to science. The descriptions of four of these new species are based solely on photographs, the fifth being described from a plaster cast in the museum at Honolulu. As suggested by the authors themselves, some of the characters used by them in their key to the species may be “matters of age not indicating specific distinction.” According to this key, the present specimen from Devonshire would appear to be referable to one of their new species—I. maguirei from the West Indies, but, so far as I am able to judge from the description and photograph, there seems to be no valid reason for separating this from I. americanus, which is found on the Atlantic coast of America from Brazil northwards to Cape Cod and beyond.
On some Factors Limiting the Habitat of Arenicola marina
Authors: Reid D. M.
Published: May 2009

In the foregoing work it was found that: Arenicola marina was repelled and could not burrow in sand containing 20% of ferric oxide in the amorphous state.

That 0·021% ferric oxide in suspension in sea-water was lethal owing to its forming with the mucus of the organism an envelope which prevented contact with the surrounding air-carrying water.

That calcium carbonate, magnesium carbonate, Stourbridge clay, kaolin, and kieselguhr had the same effect as the ferric oxide in suspension.

That although able to live for a short time in water of salinity 3·10%‰, Arenicola marina tended to become so turgid in water of 14·32%‰ as to be unable to burrow.
Notes on the Rate of Growth of Tellina tenuis da Costa in the Firth of Clyde
Authors: Stephen A. C.
Published: May 2009

1. The present paper is a direct continuation of the work done at Millport during 1926 and 1927.

2. As before, Tellina tenuis showed no growth during the winter months.

3. As before, the rate of growth at L.W.M. was less than that near H.W.M.

4. Below L.W.M. there seemed to have been no growth during the year, but there had been a heavy mortality during 1928.

5. Above L.W.M. the rate of growth during 1928 was of the same order as that of 1927, and the view that a year group was unrepresented on the 1926 curve seems justified.

6. At the end of September, 1928, the 1926 spat still formed a large and well-marked group.

7. The history of the 1926 spat is traced, and the annual increment found to be halved in succeeding years.
Photo-electric Measurements of Submarine Illumination throughout the Year
Authors: Poole H. H. , Atkins W. R. G.
Published: May 2009

Measurements were made, throughout the year 1928, of the penetration of daylight into sea-water in the English Channel. One vacuum and two gas-filled potassium photo-electric cells were used below water. In all save the first series an efficient diffusing surface was used with the photometers so that the corrections for obliquity of illumination, necessary in our earlier work, were rendered almost negligible. From October onwards a more sensitive gas-filled cell was available for use, together with a more powerful amplifier and a more efficient insulation of the high-tension batteries; improvements in the switching of the photometers on and off were also incorporated.

The following conclusions have been reached :—

1. The conclusions put forward tentatively in 1928, concerning the agreement between the vacuum and gas-filled cells, have been substantiated in the main, although the vacuum photometer, which is relatively more sensitive to the blue end of the spectrum, generally indicated rather higher opacities.

2. There are no regular seasonal changes in the opacity of the water. A very high opacity occurred in the autumn of 1927, but this was not repeated in 1928.

3. On one occasion, in April 1928, an unusual degree of clearness of the water has been shown to have been associated with the influx of water of lesser salinity, from further out in the Channel. The clearness of the water at El in December, 1927, and September, 1928, is probably due to an influx of clearer water, though the salinity changes indicating this are not so well marked.
Experimental fishing for the Spider crab, Maia Squinado: sea and laboratory trials
Authors: Rodhouse Deborah M.
Published: May 2009

Sea trials, using baited pots (inkwell and French barrel) and nets (tangle and gill), were conducted for the spider crab Maia squinado off the west coast of Ireland from November 1978 to July 1980. A series of laboratory pot trials using inkwell pots were performed. Diving observations were made on the fishing grounds.

Catch per unit effort rose to a summer peak and decreased in autumn. There was no difference in size composition or sex ratio of the catch between the pots and nets. Mature males predominated in the catch with the highest male:female (M:F) ratios recorded in summer. Immatures were virtually absent from the catch. Segregation on the basis of sex and maturity appears to occur in summer. Mature males were found at about 10 m, in sandy areas with rocky outcrops. Mature females occurred at about 5 m, on a sand and shell gravel bottom with rock and weed (notably Laminaria). Immatures were rare and occurred just below the intertidal. The M:F ratio was lowest during the periods of the onshore and offshore migrations. Berried females were recorded from March to September with one brood produced each year.

Laboratory pot trials showed increased aggression among spider crabs in the presence of baited pots. Males drove other males away from pots and divided their time between agonistic encounters and searching. Females were not driven away and did not engage in aggressive encounters. This behaviour, and the observation that large males could reach the bait through the pot bars, possibly explains the absence of larger and smaller males from the pots.
The amphipod Monoculodes gibbosus (Crustacea) in British waters
Authors: Moore P. G.
Published: May 2009

Material from Loch Fyne referable to Monoculodes gibbosus Chevreux (Oedicerotidae) has been discovered in the Reference Collection at Millport originally labelled by David Robertson as M. stimpsoni Bate. This is the first British record of this little known species. A detailed redescription is provided and comparison made with French material (including the holotype). A revised key to the British species is presented.
The reduction in growth of Mytilus edulis in fluctuating salinity regimes measured using laser diffraction patterns and the exaggeration of this effect by using tap water as the diluting medium
Authors: Gruffydd Ll. D. , Huxley R. , Crisp D. J.
Published: May 2009

In experiments to investigate the effect of low salinity on growth in Mytilus edulis, unexpected depression of growth occurred, even in sinusoidal regimes falling to only 90% of the full salinity, when tap water was the diluting medium used. The effect of various additives to the domestic water supply on the growth of Mytilus was investigated. Chlorine and fluoride had no effect although fluoride (as sodium fluoride) inhibited faeces production in a 7-day experiment. Determinations of the level of copper in the laboratory's tap water showed these to be high enough to cause depression of growth even at low dilution levels. When distilled water or lake water was used to dilute the sea water, shell growth was not affected until a sinusoidal fluctuation reaching a minimum of 50% sea water was used. Such effect did not become significant until the mussels were kept in pure fresh water for an extended period in each cycle of sinusoidal salinity variations.
Seasonal variations in gamete development in the Iceland scallop, Chlamys islandica
Authors: Sundet J. H. , Lee J. B.
Published: May 2009

Annual cycles of development were studied in male and female Iceland scallops (Chlamys islandica). Volume fractions of each germ cell type and other gonadal tissue were determined by histological and stereological techniques. Spawning occurs during a short period in late June and early July.
The temporary adhesion of barnacle cyprids: effects of some differing surface characteristics
Authors: Yule A. B. , Walker G.
Published: May 2009

The tenacity of the barnacle cyprids ofBalanus balanoides(L.) during temporary adhesion to a variety of modified Perspex surfaces was tested using a sensitive microbalance. The Perspex panels were painted on the undersides with five colours of cellulose paint. Control measurements of the magnitude of temporary adhesion to clean slate panels were of the order of 2 × 10 N m. Untreated smooth Perspex panels and panels coated with an adsorbed layer of bovine serum albumen gave low figures of tenacity of the order of 0·8 × 10 N m. Roughening the panels with carborundum or treating with an adsorbed layer of barnacle extract protein resulted in higher tenacity measurements (1·0–1·8 × 10 N M), whereas the highest measurements were obtained when roughened Perspex panels were coated by an adsorbed layer of barnacle extract protein (1·6–2·2 × 10 N M). When the surfaces were made more attractive to barnacle cyprids by roughening or coating in barnacle protein the forces measured on dark coloured panels were higher than on lighter coloured panels. The results of the temporary adhesion measurements were closely paralleled by the numbers of cyprids found exploring the various surfaces during preference settlement experiments.
A comparative study of reproductive and nutritional periodicities in two populations of Asterias rubens (Echinodermata: Asteroidea) from the English Channel
Authors: Nichols D. , Barker M. F.
Published: May 2009

Gonadial, pyloric caecal and somatic indices and oocyte size-frequencies are compared over a 3-year period for the starfish Asterias rubens from an intertidal nutritionally rich site and a subtidal impoverished site from the English Channel off south-west Britain. The intertidal population showed significantly higher values for all three indices over most of the study period compared with the subtidal population, and its spawning occurred later. The somatic index of the subtidal population showed a steeper rise than the intertidal population over that part of the cycle in which the gonads were undergoing enlargement, which gives further support to the suggestion that starfishes deprived of sufficient food may give priority to maintenance of the body-wall over enlargement of either the food-storage tissues of the pyloric caeca or the gonads.
Recolonization of a rocky shore in S.W. Ireland following a toxic bloom of the dinoflagellate, Gyrodinium aureolum
Authors: Southgate T. , Wilson K. , Cross T. F. , Myers A. A.
Published: May 2009

The mortalities and subsequent recolonization of a rocky shore in S.W. Ireland following a bloom of the toxic dinoflagellate, Gyrodinium aureolum in 1979 are described. Selective mortalities of key animal species notably grazing gastropods were followed by a marked increase in fucoid algae. Enteromorpha spp. blooms were a feature of vertical surfaces only. In general planktonic recruiting gastropods exhibited the most rapid recovery. Forty-two months after the red tide, fucoid algae still dominate both vertical and horizontal surfaces at the study area.

Introduction

Dinoflagellate blooms ('red-tides'), chiefly of Gyrodinium aureolum Hulburt have been recorded several times in Southern Ireland since 1976 (Ottway et al. 1979; Cross & Southgate, 1980; Jenkinson & Connors, 1980; Leahy, 1980; Roden, Ryan & Lennon, 1980; Wilson, 1982) and have resulted in mortalities of farmed rainbow trout in sea-cages in Dunmanus Bay (Parker, 1981). Other species of pelagic and demersal fish on the south coast were also affected by a toxic red-tide in 1976 (Ottway et al. 1979). Owing to the unpredictability of occurrence of dinoflagellate blooms, few studies on the effects of red tides on littoral fauna, and on the subsequent recolonization following the events have been carried out. Previous studies in Dunmanus Bay, Ireland (Leahy, 1980) suffered from a lack of the shores prior to the of information about the structure and dynamics occurrence of a red-tide.

Regular monitoring of the rocky shore biota at Dunmanus Bay (Myers, Southgate & Wilson, 1980) has been carried out since May 1978 and is continuing. The red tide of August 1979 caused dramatic mortalities of a wide range of taxa at Pointabulloge in Dunmanus Bay (Cross & Southgate, 1980).
Notes On molluscan meiofauna from Plymouth
Authors: Salvini-Plawen Luitfried V.
Published: May 2009

Preliminary examination of marine meiofauna from the Plymouth area, especially on mesopsammic representatives, resulted in the finding of several typically interstitial Mollusca. Among them, Caecum glabrum, Hedylopsis spiculifera, and Philinoglossa praelongata were recorded live for the first time in the area. This is also the first record of Ph. praelongata outside the Mediterranean Sea.

During a short stay at the Marine Biological Association Laboratory some preliminary studies on meiofauna were made. To obtain information especially about the interstitial fauna of marine sand, three typical samples of coarse sediment from different positions were examined.

Sample A: Plymouth Sound, Outer Cawsand Bay, Queens Ground, 50°20' 03“ N, 4° 10' 27” W; ca. 6 fathoms (=11 m); coarse sand, about 6 1 examined (14 September 1982).

Sample B: Plymouth Sound, southwest of Drake Island, 50° 21' 06“ N, 4° 09' 50” W; ca. 7 fathoms (= 13 m); coarse shell-sand, about 1 1 examined (15 September 1982).

Sample C: outer Plymouth Sound, 50° 18' 51“ N, 4° 10' 30” W; ca. 12 fathoms (– 22 m); fine gravel, about 1 1 examined (15 September 1982).

In this contribution only the gastropods are dealt with; other meiofauna will be treated ina later communication. The sole previous report of mesopsammic fauna from the Plymouth area is that of Spooner (1959). He examined two samples, one of which (Plymouth Sound) was taken fairlyclose to the above sample A, about 18“ more to the West at 4–5–5–5 fathoms (8–10 m; G. R. Forster, personal communication).
Food resource, gametogenesis and growth of Mytilus edulis on the shore and in suspended culture: Killary Harbour, Ireland
Authors: Rodhouse P. G. , Roden C. M. , Burnell G. M. , Hensey M. P. , McMahon T. , Ottway B. , Ryan T. H.
Published: May 2009

Mussels, Mytilus edulis L. grow on the shore and are cultured on ropes in Killary Harbour, a fjordic inlet on the Irish west coast. The food resource available to cultured mussels differs from that available to wild mussels on the shore. Although phytoplankton densities as estimated from chlorophyll a concentrations are similar, the shore environment in the inner part of the inlet is characterized by high mean POC concentrations. This is because of the presence of variable amounts ofallochthonous detrital carbon.

The annual cycles of flesh weight and ash content of wild and cultivated mussels were followed over two years. These cycles were related to the reproductive cycle observed by taking histological samples of mussel gonad, by plankton sampling for larvae and by monitoring larval settlement. Shell growth was measured in wild mussels by reading seasonal growth patterns on sectioned shells and in cultured mussels by following progress of the modal shell length of cohorts on ropes.

Wild mussels have a partial spawning in early spring and spawn completely in the summer. Cultured mussels spawn twice during the summer, in the year following settlement. Growth rate of wild mussels decreases with increasing aerial exposure. The fastest growing mussels, at o % exposure, take about 6 years to attain the length attained by the mode of the cultured mussels after 18 months, when they are harvested.

We conclude that wild mussels utilize a mix of phytoplankton and detritus as food during the summer and that large wild mussels can use detritus during the autumn and early winter for an increase in flesh weight and gametogenesis.
Evidence for the existence of a third, ecologically distinct morph of the anemone, Actinia equina
Authors: Quicke D. L. J. , Brace R. C.
Published: May 2009

An examination of the proportions of pedal disc colour and isozyme phenotypes, in samples of Actinia equina L. collected from around Britain, has shown that individuals which are heterozygous for a gene complex involved in morph determination occupy a habitat intermediate in position to those occupied by the two homozygotes. It is concluded that A. equina may best be considered as comprising three morphs, rather than two as had been distinguished previously.

As the abundance of anemones in samples displaying a particular pedal disc colour phenotype decreases, the proportion of these individuals which possess atypical combinations of colour and hexokinase-i phenotypes increases. This result is interpreted as indicating that individuals are subject to differential selection in different habitats, dependent upon their genotypes at hexokinase-i, or those at some other tightly linked locus.

Introduction

Our recent work on Actinia equina L. has revealed the existence of two morphs amongst anemones collected from British coasts, having column coloration ranging from red to brown (Quicke, Donoghue & Brace, 1983). One morph displays pedal disc colour (coloration) (PDC) ranging from red to pink (R), and occurs in the upper part of the intertidal range of this species, where it is commonly found firmly attached to vertical rock faces. The other has a grey (G) or green (H) pedal disc, which may sometimes display contrasting red or orange radial lines (L); these colour phenotypes will be collectively referred to as GHL. This latter morph occurs predominantly at a lower tidal level, where it usually occurs on horizontal surfaces to which it adheres relatively weakly.
The uptake of guanine and hypoxanthine by marine microalgae
Authors: Shah N. , Syrett P. J.
Published: May 2009

Guanine and hypoxanthine were excellent sole nitrogen sources for several microalgal species grown in axenic culture. Of the algae studied onlyChlorella stigmatophoragrew well on pyrimidines. Freshly harvested nitrate or ammonium-grown organisms generally lacked ability to take up guanine or hypoxanthine but this ability developed during several hours of photosynthesis in nitrogen-free medium. Nitrate-grown (but not ammonium-grown)Tetraselmis subcordiformisandChlorella fuscacould take up guanine, the initial rate of uptake increasing when the cells were also nitrogen-deprived. Of the algae studied onlyChlorella vulgarisandAttheya decorarequired prior incubation with guanine before being able to take it up.Porphyridium purpureumdid not take up guanine. Factors affecting the development of ability to take up guanine and the characteristics of guanine transport were studied. The transport systems showed Michaelis-Menten type kinetics with K s values ranging from 05 to 3–7/IM guanine. In marine species, guanine uptake was dependent on the presence of Nations in the medium butChlorella stigmatophorashowed less dependence on Na+ than other species.
Enzymes of purine metabolism in the diatom,Phaeodactylum tricornutum
Authors: Shah N. , Syrett P. J.
Published: May 2009

Cell-free extracts ofPhaeodactylum tricornutumcontained a methyltransferase which catalysed the methylation of guanine or hypoxanthine by 5–adenosyl-methionine. The product ofthe reaction appeared to be a methylhypoxanthine irrespective of whether guanine or hypoxanthine was substrate. This enzyme activity (per unit protein) trebled during 6 h of nitrogen deprivation. It is suggested that this enzyme is responsible for the methylation of guanine and hypoxanthine when these are taken up by nitrogen-deprived intact cells. Uricase, allantoinase and allantoicase were present in cells incubated with guanine, hypoxanthine, uric acid or allantoin;these activities did not appear during nitrogen-deprivation. Crude cell-free extracts containedaninhibitor of uricase and activity could be demonstrated only after ammonium sulphate precipitation of protein. When these three enzymes were induced by incubation with guanine, their order of appearance was identical to the order in which they operate in purine catabolism, namely (i) uricase (ii) allantoinase (iii) allantoicase. Guanine deaminase, xanthine oxidase and xanthine dehydrogenase activities were not detected irrespective of whether cells were nitrogen-deprivedor incubated with purine.
Larval ascaridoid nematodes in myopsid and oegopsid cephalopods from around Scotland and in the northern North Sea
Authors: Smith John W.
Published: May 2009

Four squid species from around Scotland and in the northern North Sea were examined for larval ascaridoid nematodes maturing in warm-blooded vertebrates. A larval contracaecinean (possibly Contracaecum osculatum) in Loligo forbesi, and Anisakis simplex L in L. forbesi, Alloteuthis media and Todaropsis eblanae are recorded, apparently for the first time. Neither of the inshore neritic myopsids L. forbesi and A. media appears to be an important host of Anisakis simplex L3. The oceanic oegopsid Todarodes sagittatus showed the highest A. simplex L3 burdens; whilst the general pattern of infection in this species was similar to that of teleost fish in the northern North Sea, the density of infection was lower. The possible significance of L3 in squid for the population dynamics of A. simplex is discussed. Larval ascaridoid nematodes in squid may have no public health significance in the U.K.