bluuebunny/crossref_metadata_2025 huggingface dataset:
Meiobenthos of Sub-Littoral Muds
Authors: McIntyre A. D.
Published: May 2009

Meiobenthos, here defined as metazoans passing through a ½ mm screen, is described from core samples collected on muddy grounds at 100-140 m depth in the North Sea and off the west coast of Scotland between February 1962 and August 1963.

Sixteen cores of 2·2 cm diameter were collected from Loch Nevis, and 14 from the Fladen ground. The top 7 cm of each core was passed through a 500μ then a 76μ screen. The residues were examined entire, and the nitrate of the finest mesh was subsampled.

The fauna consisted mainly of nematodes, kinorhynchs, ostracods, copepods, polychaetes, and lamellibranchs. Between 61 and 97 % of the population consisted of nematodes, but copepods were second in importance and were more abundant than recorded on other subtidal grounds.

The fine mesh (76μ) retained almost all specimens of every animal group except Nematoda. Numerically 38% of the nematode population passed through the fine sieve, but this represented only 18% by weight.

The mean dry weight of meiobenthos on Fladen was calculated as 0·76 g/m2 and the average number of individuals was 196 × 104/m2.

In Loch Nevis the corresponding weight was 1·28 g and the number 101 × 104. The loch had a larger and more varied population of all groups except nematodes, which were particularly abundant on Fladen.

The data do not indicate significant population fluctuations throughout the year in the permanent meiobenthos.

Compared with other subtidal grounds Nevis and Fladen seem to support much richer populations, and the high values for Fladen are of particular interest since this is a poor macrobenthos area.

An attempt is made to indicate the possible level of meiobenthos productivity and it is suggested that there may be competition between meio- and macrobenthos for available organic matter which could result in a less efficient production of fish food.
Vitamin A and Carotenoids in Certain Invertebrates VII. Crustacea: Copepoda
Authors: Fisher L. R. , Kon S. K. , Thompson S. Y.
Published: May 2009

Total fat, carotenoids, and vitamin A were determined physicochemically in sixty-nine species and fifteen generic groups of pelagic marine copepods.

Vitamin A was definitely present inEuchirella curticaudaand Gaetanuskruppiand possibly so inGaetanus pileatusand in a sample ofGaetanusspp. No vitamin A activity for vitamin A-depleted rats was found in fractions from a lipid extract of 1854 g ofCalanus finmarchicus.

The significance of these findings is considered in relation to the high vitamin A reserves in many fish preying upon pelagic copepods.
Oxygen Uptake of Developing Eggs and Larvae of the Herring (Clupea Harengus)
Authors: Holliday F. G. T. , Blaxter J. H. S. , Lasker Reuben
Published: May 2009

The oxygen uptake of eggs and larvae of Norwegian herring from Bergen (mean unfertilized egg dry weight about 035 mg) and of Baltic herring from Kiel (mean unfertilized egg dry weight about 0·10 mg) was measured by a reference diver and a Warburg respirometer. Anaesthetized Kiel larvae had values of about 0·10μl./larva/h and Bergen larvae 0·25μl./larva/h. When expressed as Qo(μl./mg dry weight/h) the values became Kiel 2·3, Bergen 2·5.

Oxygen uptake of embryos before hatching and of larvae, expressed as Qo, was most affected by activity, increasing in very active organisms by five to ten times the resting value of 1-2 μl./mg dry weight/h. Experiments to test the effects of temperature and salinity were done using anaesthetized larvae in some cases.

Temperature experiments with larvae gave a Q10of about 2, the Qo, of anaesthetized Kiel larvae ranging from about 2·0 at 50° C to 35 at 14°C, and that of unanaesthetized Bergen larvae from 2·5 at 6° C to 50 at 140°C.

Eggs and larvae of both races reared in salinities from 5 to 50 %0 showed no detectable difference in oxygen uptake. However, abrupt transfer of anaesthetized larvae from one salinity to another caused violent fluctuations (by up to ten times) before adaptation took place. Buoyancy differences appeared to mask differences in oxygen uptake of unanaesthetized larvae in similar transfer experiments.

There was little tendency for oxygen uptake to become reduced during darkness in either Bergen or Kiel larvae.

The effect of age on oxygen uptake (expressed as Qo) was not marked, though there tended to be a peak at, and just after, hatching, with a tendency for a fall off during starvation.
The Hydroids and MedusaeSarsia OccultaSp.Nov.,Sarsia TubulosaandSarsia Loveni
Authors: Edwards C.
Published: May 2009

The discovery of a new species ofSarsiahydroid and its medusa and a comparison of this species withSarsia tubulosa(M. Sars) and S. loveni (M. Sars) have resolved a longstanding problem. In his detailed account of the hydroid and medusa Coryne mirabilis (now accepted as identical and synonymous withSarsia tubulosa), Louis Agassiz (1860-2, vol. 4, pp. 189-90, 203-4, P's- 17J i8) asserted that it undergoes a change of reproduction in winter and spring. He stated that in late winter the hydroid releases medusae but that in spring the gonophores no longer develop into normal medusae, being retained on the hydranths where they become sexually mature without mouth and tentacles. He based his conclusions on a series of hydroid colonies collected on the shore. Allman (1871-2, pp. 278-9) was strongly disinclined to accept Agassiz's assertion of the specific identity of the two forms of gonophore without stronger evidence, saying that, until the two kinds were found simultaneously or in succession on one colony kept under close observation in an aquarium, the identity of the two forms could not be accepted as proved. Mayer (1910, p. 55), from personal observation of colonies collected on the coast of Massachusetts, came to the same conclusion as Agassiz, but he did not say whether he had followed the succession in an aquarium or had observed one colony throughout, and accordingly his conclusion is subject to the same criticism.
Life-Histories and Abundance of Epizoites of the Hydroid Nemertesia Antennina (L.)
Authors: Hughes R. G.
Published: May 2009

In Torbay, Nemertesia antennina (L.) hosts more than 150 epizoic species, most of which do not occur on other substrata in the area (Hughes, 1975). Five species, the amphipods Ericthonius brasiliensis (Dana), Pseudoprotella phasma (Montagu) and Corophium sextoni Crawford, and the gastropods Cingula semistriata (Montagu) and Cingula semicostata (Montagu), constitute 68 % of the free-living epizoites and are sufficiently abundant throughout the year to allow a study of their life-histories.
Some Observations Upon the chemical Composition of the Starfish Asterias Rubens L., with Particular Reference to Strontium Uptake
Authors: Binyon John
Published: May 2009

The publication in 1953 of the English language translation of Vinogradov＇s massive compilation of data upon the chemical composition of numerous animals was a valuable landmark in this field of study. Since then, papers too numerous to summarize, have appeared in the literature employing ever more accurate analytical techniques. So far as marine animals in particular are concerned, the theme which has been consolidated by such subsequent work revolves around their ability to extract and concentrate a variety of chemical elements from their environment. Frequently, however, no obvious function can be ascribed to the more obscure of these often highly concentrated elements.
Ciliated Sensory Cells in Amphioxus (Branchiostoma)
Authors: Bone Q. , Best A. C. G.
Published: May 2009

Various workers during the past century have figured sensory cells bearing cilia amongst the ordinary non-ciliated epidermal cells of the body surface. Similar sensory cells were also found on the buccal cirrhi, and on the velar tentacles at the entry to the atrium. This earlier work at the light microscope level was summarized by Franz (1923) in his excellent review. More recently Schulte & Riehl (1977) have re-examined the innervation of the oral region and buccal cirrhi at the ultrastructural level, and observed two types of sensory cell in these regions, distinguished by their apical structure. They suggest that these are both secondary sensory neurons (as Franz had previously surmised), but their figures hardly make this suggestion convincing. In this note we show that there is probably only a single type of sensory cell amongst the epidermal cells of the body surface and buccal cirrhi; that it synapses at its base with incoming axons of central cells, and that a different type is indeed found in amphioxus, but only in the velar tentacles.
The Factors Influencing the Distribution of Saccorhiza Polyschides in the Region of Lough Ine
Authors: Norton Trevor A.
Published: May 2009

Saccorhiza polyschides (Lightf.) Batt. is a laminarian alga found in the sublittoral region. It is widely distributed around the shores of the British Isles and is particularly common on the south west coast of Ireland. A puzzling aspect of the distribution of the species in Southern Ireland is its absence from Lough Ine, in County Cork.
Cirral Activity and Feeding in the Verrucomorph BarnaclesVerruca RectaAurivillius andV. Stroemia(O. F. Müller) (Cirripedia)
Authors: Anderson D. T.
Published: May 2009

Previous studies on cirral activity in thoracican cirripedes have established two basic patterns of feeding action. In the Lepadomorpha, the Verrucomorpha, and the chthamaloid and coronuloid Balanomorpha, prolonged cirral extension provides the basis for captorial feeding. The cirri are held extended and are used, individually or collectively, to capture small live prey. Investigations on these species have yielded no evidence of sustained rhythmic cirral activity as a component of food collection among a variety of species (Crisp, 1950, 1967; Southward, 1957, 1962, 1967; Mori, 1958, 1961; Southward & Southward, 1958, 1967; Barnes & Reese, 1959; Howard & Scott, 1959; Patel, 1959; Crisp & Southward, 1961; Southward & Crisp, 1965; Bieri, 1966; Jones, 1968; Stone & Barnes, 1973; Klepal & Barnes, 1975).
Spat Settlement of the Scallops Chlamys Opercularis (L.) and Pecten Maximus (L.) On Artificial Collectors
Authors: Brand A. R. , Paul J. D. , Hoogesteger J. N.
Published: May 2009

Scallops of the bivalve family Pectinidae are very valuable shellfish and the subject of various important commercial fisheries around the world. Most of these fisheries are at present dependent upon natural populations, which can fluctuate widely in abundance from year to year due to irregular recruitment and overfishing. In recent years there has been considerable interest in the possibilities of cultivating various scallop species and some success has been obtained in rearing larvae of Pecten maximus (L.) in the laboratory (Comely, 1972; Gruffydd & Beaumont, 1972). However, by far the most successful cultivation system developed for pectinids has been carried out for several years in Japan for Patinopecten yessoensis (Jay). Naturally produced spat settling on Collectors made from artificial materials are grown on to market size in cages in the sea or used to restock natural beds (Ito, Kanno & Takashashi, 1975; Querellou, 1975; Motoda, 1977).
Changes in the Ultrastructure of the Gill Epithelium of Patella Vulgata after Exposure to North Sea Crude Oil and Dispersants
Authors: Nuwayhid M. A. , Davies P. Spencer , Elder H. Y.
Published: May 2009

Intertidal organisms are particularly prone to the effects of both crude oil and to the chemicals commonly used to disperse the oil, following an oil spill at sea (Smith, 1968). A large body of literature now exists on the lethal effects of crude oil and dispersants but little progress has been made towards elucidating the toxic mode of action of these chemicals, nor to understanding what effects they exert when present in sub-lethal concentrations. Since the gills of aquatic animals are generally the most delicate of the epithelia exposed to the environment, it is likely that they will be most prone to damage by pollutants. Whilst previous workers using light microscopy (e.g. Clark, Finley & Gibson, 1974; Blanton & Robinson, 1973) have reported gross damage to the gills of mussels and fish following exposure to crude oil, there was no information available on the nature of the cellular damage at the ultrastructural level. In this study, we describe the nature of the lesions produced in the gills of the common intertidal limpet Patella vulgata following exposure to the water soluble fraction of North Sea crude oil and to the dispersants BP 1100 X and BP 1100 WD. A description of the ultrastructure of normal gill plates of Patella has been published previously (Nuwayhid, Davies & Elder, 1978).
Deep-Water Sipuncula from the Gulf of Gascogne
Authors: Cutler E. B. , Cutler N. J.
Published: May 2009

An intensive study of the benthos at six deep-water stations in the Gulf of Gascogne was undertaken by the Centre Océanologique de Bretagne, Brest (during 1972–4) (Laubier & Sibuet, 1977, fig. 1). These stations were repeatedly sampled with a variety of gear during seven different ‘Biogas’ cruises, and over 1900 sipunculans belonging to 16 species including one new to science were collected. Table 1 lists these species and their abundance at the six stations. Specific station data on the samples can be obtained from the authors.

The ubiquitous nature of sipunculans is well documented by this work. Of the 72 dredge hawls made, 86% contained sipunculans, while 80% of the 54 trawl collections yielded sipunculans. Sample CP 01 with 165 sipunculans belonging to five species was the richest collection. The efficiency of the collecting gear and richness of the fauna is indicated by the fact that 24% of the individual collections yielded four or five species while 12% yielded 6–9 species, compared with the usual 1–3 species often collected. At Sample DS 62 a single haul yielded nine out of the 12 species at Station 1.

The following section contains brief comments on the species and their distribution. Full descriptions of these species and additional references can be found in Stephen & Edmonds (1972) and Cutler (1973). The subgenera ofGolfingtafollow Cutler & Murina (1977) and Cutler (1979).
Pacific Spirorbids In The East Atlantic
Authors: Knight-Jones E. W. , Knight-Jones Phyllis
Published: May 2009

The faunas of volcanic islands must necessarily be introduced, and more recent introductions can be recognized by the patterns of their distributions. This is obvious in the Canary Islands, where we have spent 30 days studying distributions of Spirorbidae. We now regard these as a distinct family following Pillai (1970). We sampled all the major islands, by shore collecting and diving to about 10 m, and on almost all we found nine Mediterranean species, namely Protolaeospira striata (Quiévreux, 1963) and the eight opercular incubators (species of Pileolaria and Janua) that have been recorded from both Marseilles (Zibrowius, 1968) and Chios (Bailey, 1969).
Dispersal by Benthic Invertebrates: The in Situ Swimming Behaviour of the Amphipod Corophium Volutator
Authors: Hughes R. G.
Published: May 2009

Studies of the dispersal behaviour of marine and estuarine benthic invertebrates have concentrated on the majority of species where the individuals disperse as a planktonic larva. The view that seems to be prevalent, summarised by Crisp (1974, 1976), is that larvae are an adaptation to allow species to colonise transient habitats and for species with adults of limited mobility to colonise distant habitats. The spreading of the species over wide areas has the advantages of reducing competition and facilitating greater genetic diversity, leaving the species more adaptable to subsequent environmental changes. These advantages are greater with longer distances travelled, and are an explanation for larvae spending up to several weeks drifting in the plankton, despite the acknowledged high mortality rates associated with the pelagic existence.
A Comparison of the Effectiveness of Tri-N-Butyltin Chloride and Five other Organotin Compounds in Promoting the Development of Imposex in the Dog-Whelk, Nucella Lapillus
Authors: Bryan G. W. , Gibbs P. E. , Burt G. R.
Published: May 2009

Populations of the common dog-whelk Nucella lapillus (L.) are declining or have already disappeared at many sites on rocky shores around the United Kingdom (Bryan et al. 1986). There is conclusive evidence that this is caused mainly by tributyltin (TBT) compounds leached from ships' antifouling paints (Bryan et al. 1987). These compounds impose male sexual characters (or imposex) on female N. lapillus. Other stenoglossan gastropods including Nassarius obsoletus Say (Smith, 1981a) and Ocenebra erinacea (L.) (Féral & Gall, 1982) are similarly affected by TBT. The intensity of expression of imposex in N. lapillus can generally be related to the sea water concentration of TBT. The appearance of a small penis and the partial development of a vas deferens first occurs at TBT concentrations below 0.5 ng/1 (as tin), although reproduction appears to be unaffected at this level. At 1–2 ng Sn/1 penis size is markedly increased and in some females proliferation of vas deferens tissue overgrows the genital papilla, thus sterilizing the animal. At slightly higher concentrations virtually all females become sterilized and at around 10 ng Sn/1 oogenesis is suppressed and spermatogenesis initiated (Gibbs, Pascoe & Burt, 1988). Since development is direct and there is no planktonic stage, N. lapillus has a very limited capacity for dispersion: thus the sterilization of females heralds the almost certain decline of so affected populations (Gibbs & Bryan, 1986).
Fecundity and Seasonal Changes in Reproductive Output of Females of the Gravel Beach Amphipod, Pectenogammarus Planicrurus
Authors: Bella M.C. , Fish J.D.
Published: May 2009

Pectenogammarus planicrurus Reid (Crustacea: Amphipoda) is an inhabitant of unstable gravel beaches. The reproductive output of females of this species was studied at Aberystwyth, on the west coast of Wales. There was marked seasonal variation in the size of eggs: the mean volume of eggs at an early stage of embryonic development ranged from 0·023 mm3 in summer to 0·030 mm3 in winter. Egg size was negatively related to brood size, but seasonal variation in brood size was greater than could be accounted for by egg size alone. Mean brood size ranged from 1·4 eggs in winter to 5·9 eggs in summer. Brood size was also strongly related to female body size, ranging up to 14 eggs in a large female. These findings are discussed in relation to adaptation to interstitial living in coarse intertidal gravels. A model of seasonal variation in reproductive output is suggested in which the importance of point reproductive output is related to the probability of females surviving to produce subsequent broods.
Planktonic Dispersion of Larval Salmon-Lice,Lepeophtheirus Salmonis, Associated with Cultured Salmon,Salmo Salar, in Western Ireland
Authors: Costelloe Mark , Costelloe John , Roche Nicola
Published: May 2009

Dispersion ofLepeophtheirus salmonisKreyer 1838 (Crustacea: Caligidae) larvae from a single cage and also from a farm system was investigated in Ardmore Bay, west coast of Ireland. Surface plankton tows were taken from within a cage and also at various distances from the farm. Highest densities of larvae (maximum, 66·1 m−3) were consistently recorded within the cage. Less than 10% of the larval density recorded inside the cage was found outside at any one time, indicating a high retention of larvae within the cage throughout the sampling period. This was due to a reduction of water movement inside the cage caused by the physical barrier of the net which was fouled during the sampling period. Highest densities of larvae were consistently found in samples taken at 10 m (maximum, 4·8 m−3) from the last cage on the farm in comparison to those taken further away from it (maximum, at 1 km; 0·4 m−3). Regression analysis of the data from each of the sampling dates showed a significant inverse relationship (P=0·001) between distance and larval numbers. The models produced suggest that few louse larvae would have been recovered in samples (i.e. 100 m plankton surface tows) taken more than 2 km from the last cage on the farm. Although the ratio of copepodids to nauplii increased with distance from the farm, the densities of the copepodids did not increase.
An Estuarine Biodiversity Hot-Spot
Authors: Attrill Martin J. , Ramsay Paul M. , Thomas R. Myles , Trett Marcus W.
Published: May 2009

From 1989–1992, at quarterly intervals, the National Rivers Authority (NRA) (Thames Region) Thames Estuary Benthic Programme sampled 28 sites within the estuary for benthic macroinvertebrates; meiofauna samples were also taken for the first year. At one subtidal site, situated off Canvey Island, over 200 invertebrate species over the survey period from a sample area of 4·4 m2 were recorded. This species richness was far higher than surrounding sites, including those further out into the North Sea. The most important groups at this site were Nematoda (77 spp.), Crustacea (46 spp.) and Polychaeta (40 spp.) and a species capture curve for macroinvertebrates continued to rise after 44 day grabs. The mean biomass of the site (248 g wet weight /m2) was 20 times that of any other site in the outer estuary. The substratum at the site was highly heterogeneous, yet comparatively stable due to its situation at the base (>20 m depth) of a man-made shipping channel, the provision of a large number of niches perhaps explaining the high biodiversity. The anthropogenic influence on a naturally low biodiversity area emphasises the importance of these ecosystems when considering the conservation of global biodiversity. Methods to determine the relative importance of ecosystems are discussed.
A Study of Global Biodiversity Patterns in the Marine Motile Fauna of Hard Substrata
Authors: Gee J.M. , Warwick R.M.
Published: May 2009

A global study of latitudinal gradients in biodiversity of marine shallow-water, motile epifauna of hard substrata has been initiated by Plymouth Marine Laboratory and the International Association of Meiobenthologists. It is based on the use of artificial substratum units (ASUs) consisting of four pan-scourers and emphasizes the standardization of habitat type and complexity, sample area, sampling strategies, sample processing and analysis. Non-comparability of these factors has invalidated some of the few previous studies on global patterns in biodiversity of marine benthic communities which are reported in the literature. A list of sampling locations and participating research organizations is given along with some preliminary results from one location (south-west England).
The Effects of Fishing on Coral Reef Fish Abundance and Diversity
Authors: Watson Maggie , Righton Dave , Austin Tim , Ormond Rupert
Published: May 2009

The effect of artisanal fishing on the abundance and diversity of coral reef fish assemblages was investigated in the Kisite Marine National Park and Mpunguti Marine National Reserve at Shimoni, Kenya. Fishing is prohibited within the Park whereas in the Reserve artisanal fishing using traditional methods is practised. Visual censuses of six representative reef fish families (Chaetodontidae, Lethrinidae, Lutjanidae and Serranidae in 1992 and 1994, and Labridae and Pomacentridae in 1994 only) were undertaken along 250×10 m band transects on two similar pairs of reefs subject to differing fishing pressure. The abundance of commercial species (Lethrinidae, Lutjanidae and Serranidae) was depressed in the Reserve. The unfished butterflyfishes (Chaetodontidae) and damselfishes (Pomacentridae) also showed a greater abundance in the Park than in the Reserve. However, neither species number nor Shannon diversity (H′) of any of these families was affected by fishing pressure. Possible reasons for these findings are discussed. The abundance of commercial species, though not of non-commercial unfished species, increased significantly in the Reserve between 1992 and 1994, suggesting that the unfished Park may be acting as a source of larvae or supply of emigrating adults for the depleted Reserve. The results are comparable with other recent studies describing the effects of fishing pressure and also with those studies detailing the effects of habitat refugia in coral reef areas.
Hidden Diversity in Marine Algae: Some Examples of Genetic Variation Below The Species Level
Authors: Van Oppen Madeleine J.H. , Klerk Hans , Olsen Jeanine L. , Stam Wytze T.
Published: May 2009

An important aspect of marine biodiversity studies is identification of species and subspecies complexes. Here we present a number of examples from marine algae in which allozymes, DNA sequences and RAPDs are used to identify cryptic species and explore phylogenetic-population level relationships over several biogeographic spatial and temporal scales. In addition to evidence for recent dispersal over large distances, effects of present and past climates are reflected in the phylogenetic history of many biogeographic complexes. In some cases temperature adaptations can also be detected. Phylogeographic studies on coastal seaweeds and oceanic phytoplankton which utilize molecular genetic data contain a wealth of previously unrecognized information relevant to biodiversity.
Seasonal Variation in the Offspring Development ofOnchidoris Bilamellata(Gastropoda: Nudibranchia)
Authors: Lafuente Isabel
Published: May 2009

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

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

The field observations were carried out on the south-eastern coast of Scotland (56°18′N 2°39′W) from July 1993 to August 1994. The surface sea-water temperatures were recorded from January 1993 to August 1994 in St Andrews (56°20′N 2°47′W), seven miles from the location under study (Figure 1).
Long Term Trends in the Discovery Of Marine Species New to Science Which Occur in Britain and Ireland
Authors: Costello Mark J. , Emblow Chris S. , Picton Bernard E.
Published: May 2009

Marine species new to science continue to be discovered around Britain and Ireland. The number of marine species described each year was plotted against time for Pisces, Echinodermata, Anthozoa, Bivalvia, Decapoda, Gastropoda, Bryozoa, Tunicata, Medusozoa, Amphipoda, Porifera, Nudibranchia, Polychaeta, Copepoda, Oligochaeta, and Nematoda. Trends suggest that the latter four taxa in particular, in which individuals generally have a small body size, still have many species remaining to be described. More conspicuous taxa are better known, but new species continue to be described. Whilst the World Wars and advent of new scientific techniques do not appear to have had significant impacts on the general trends in discovery of new species, individual scientists have made major contributions.
Osmoregulation of the Estuarine PrawnPalaemon Longirostris(Caridea: Palaemonidae)
Authors: Campbell Peter J. , Jones M.B.
Published: May 2009

The caridean prawnPalaemon longirostris(Milne-Edwards) (Palaemonidae) occurs predominantly in the upper regions of large river estuaries in Europe, and reaches its northern limit of geographical distribution along southern parts of Britain (Smaldon, 1979). All post-larval stages are thought to live under dilute and fluctuating salinity conditions, although there are conflicting reports as to whether ovigerous females need to migrate to the sea at times of egg hatching (Gurney, 1923; Fincham & Furlong, 1984). The species has been known to be extremely euryhaline for some considerable time (Gurney, 1923), yet the salinity tolerance limits of larval (Antonopoulou & Emson, 1989) and post-larval stages (Campbell & Jones, 1989) have been established only recently. Apart from studies on salinity tolerances, and some preliminary measurements of blood and urine osmolality (Parry, 1957), the osmoregulatory adaptations ofP.longirostristo its dynamic habitat have not been investigated previously. The present paper describes the osmoregulatory responses ofP.longirostrisacclimated to a wide range of salinities, and also reports on the ability of individuals to compensate for sudden acute salinity change.
Relative Intraspecific Aggressiveness of Pedal Disc Colour Phenotypes of the Beadlet Anemone, Actinia Equina
Authors: Brace R.C. , Reynolds H.A.
Published: May 2009

Anemones of the genus Actinia exhibit a well documented, stereotyped aggressive sequence (Bonnin, 1964; Brace & Pavey, 1978; Brace et ah, 1979) involving specialized, nematocyst-bearing structures called acrorhagi, which can be directed against an opponent. Experiments on the Australian species, A. tenebrosa Farquhar, and on the clonal anemone, Anthopleura elegantissima (Brandt) (which similarly bears acrorhagi), indicate that aggression occurs principally between genetically dissimilar (allogeneic) opponents (Ayre, 1982; Francis, 1973a, b; Bigger, 1980). Once acrorhagial contact has been made with an allogeneic individual, massive discharges of nematocysts ensue, which can cause severe necrotic lesions.
The Succession of Generations and Growth of the Caligid Copepods Caligus Elongatus and Lepeophtheirus Salmonis Parasitising Farmed Atlantic Salmon Smolts (Salmo Salar L.)
Authors: Tully Oliver
Published: May 2009

Infestation of cage cultured Atlantic salmon by the external parasitic copepods Caligus elongatus (Nordmann) and Lepeophtheirus salmonis (Kröyer) is a serious cause of loss of production in the commercial sea water culture of this species. The copepods feed on the mucus, skin and blood of their hosts (Kabata, 1974; Brandal et al., 1976) causing irritation and lesions. Loss in production due to infestation by lice occurs directly by the mortality of fish from osmotic shock and indirectly from a probable reduction in growth, from secondary infections such as vibriosis (Wootten et al., 1982) or by increasing vulnerability to ultraviolet radiation damage (McArdle & Bullock, 1987).
Patterns of Excitation of the Lateral Line of the Ruffe
Authors: Gray J.A.B. , Best A.C.G.
Published: May 2009

Studies on the lateral lines of the sprat {Sprattus sprattus (L.); Clupeidae; Clupeiformes) have shown that the patterns of excitation of the neuromasts in the canals on the head changed dramatically with relatively small changes of position of the fish with respect to a source (Denton & Gray, 1983; Gray, 1984). It was concluded that, in the case of the sprat, this sensory system was capable of providing the information needed to maintain position in relation to other fish in a school; cf. the work of Partridge & Pitcher (1980) on saithe (Pollachius virens; Gadidae; Gadiformes). The structure of lateral lines varies greatly between fish of different species and even between different parts of the same fish. It seems likely that these differences have evolved to meet different behavioural needs. An attempt has been made to understand the mechanisms of lateral line excitation in general. This has led to the development of methods to calculate first approximations of likely excitation patterns from a knowledge of the morphology of particular systems (Denton & Gray, 1988).
Recolonisation of Artificial Sediments in the Deep Bay of Biscay By Tanaidaceans (Crustacea: Peracarida), With a Description of a New Species of Pseudotanais
Authors: Bird G.J. , Holdich D.M.
Published: May 2009

One of the more recent aims of deep-sea biological investigations has been to assess the rates and processes involved in the recolonisation of deep-sea sediments by the in situ fauna (Grassle, 1977; Desbruyères etal., 1980, 1985; Levin & Smith, 1984). The spur to such initiatives has been the prospect of deep-sea mineral exploitation and the dumping of radioactive and other chemical wastes (Desbruyères etal., 1 985), in addition to the testing of hypotheses about deep-sea community regulation (Levin & Smith, 1984; Smith, 1986). These experiments have shown that perturbated or defaunated sediments incubated for periods of several months are readily recolonised by deep-sea animals, although the process is much slower than in comparable shallow-water situations (e.g. Levin, 1984; Zajac & Whitlach, 1982a, b). Furthermore, the resulting community of colonists may be quantitatively and qualitatively different from the ‘background’ fauna (Grassle, 1977; Levin & Smith, 1984). Similar experiments have examined the effect of large ‘food-parcels’ on the in situ sediments and fauna (Smith, 1986), and a review of the responses of benthic faunas to disturbed sediments has been published by Thistle (1981).
A Presumed Male of the Parthenogenetic Amphipod Corophium Bonnellii (Milne-Edwards)
Authors: Myers A.A. , Mcgrath D. , Cunningham P.
Published: May 2009

Corophium bonnellii (Milne-Edwards) has been suspected of being parthenogenetic for more than fifty years (see Crawford, 1937) and this suggestion has been supported by recent breeding experiments (Moore, 1981). Many thousands of specimens have been examined by taxonomists and ecologists from a wide geographical area in both hemispheres, yet only Toulmond & Truchot (1964) have claimed to have found a male. No description or figures were presented by Toulmond & Touchot (1964) to support their contention.
Seasonal Changes in the Lipid Composition of Herring (Clupea Harengus) in Relation to Gonad Maturation
Authors: Henderson R.J. , Almatar S.M.
Published: May 2009

It is well established that the lipid content of the herring Clupea harengus from the waters around the British Isles and Ireland undergoes a marked seasonal cycle, being highest during the summer months of active feeding and lowest after a winter fast (Wood, 1958; lies & Wood, 1965; Lovern & Wood, 1937; Molloy & Cullen, 1981; Wallace, 1986). In the case of spring-spawning herring, the minimum lipid content coincides with the spawning period and the depletion of lipid over winter corresponds with the development of gonads (Lovern & Wood, 1937).
Possible Wavelength Discrimination by Multibank Retinae in Deep-Sea Fishes
Authors: Denton E.J. , Locket N.A.
Published: May 2009

Experiments on intact retinae from the eyes of the deep-sea fishDiretmus argenteusshow that the region of the retina that receives light from above and possesses very long rods has different photosensitive pigments from the region that receives light from below. In both of these regions the retina has several banks of rods. The optical densities of thephotosensitivepigments in the retina at the peaks of absorption are almost the same (about one) in these two regions. However, the region of the retina with very long rods also contains astableyellow pigment that absorbs heavily in the blue and near ultra-violet (optical density about three at the wavelength 390 nm). If, as seems certain, this stable pigment is largely in the long rods it will filter the light reaching the other layers of rods and act, for this region, as yellow lenses do for whole retinae in other fish. The lens ofDiretmuswas shown to be transparent in the visible and near ultra-violet.
Experimental Studies of the Reproductive Behaviour of the Parasitic Copepod Lernaeocera Branchialis (Pennellidae)
Authors: Anstensrud Morten
Published: May 2009

Egg-producing Lernaeocera branchialis (L.) are usually found in the gill cavity of cod (Gadus morhua (L.)) and whiting (Merlangius merlangus (L.)) (Kabata, 1979). The early larval development of the copepod includes two free-swimming nauplius stages followed by the first infective stage, the copepodite (Sproston, 1942). On an intermediate host, usually flounder (Platichthys flesus (L.)), the copepodite moults into a chalimus larva which is attached by its frontal filament to the gill tips of its host. After four successive chalimus stages, the parasite reaches maturity and copulation occurs on the flatfish host.
An Analysis of the Microgrowth Bands in the Shell of the Common MusselMytilus Edulis
Authors: Richardson C.A.
Published: May 2009

The periodicity of microgrowth patterns observed in thin sections and acetate peel replicas of radial sections of bivalve shells are well documented for both intertidal and subtidal species (Pannella & MacClintock, 1968; Rhoads & Pannella, 1970; Evans, 1972, 1975; Kennish, 1980; Richardsonet al., 1979et seq.; Richardson, 1987a, b, 1988, b). In many species daily or tidal lines are well preserved in the shell, for example, the hard-shell clamMercenaria mercenaria(Pannella & MacClintock, 1968), the cockleCerastoderma edule(Richardsonet al., 1979) and the clamTapes philippinarum(Richardson, 1987a, 1988b), while in others they are poorly preserved or lacking. Such an example is the common musselMytilus edulis(L.) where fine growth lines seen in acetate peel replicas have previously been reported to be poorly preserved, with long continuous sequences of such lines seldom occurring (Lutz, 1976). The angular relationship of growth lines to the growing margin and to the crystalline elements of the shell structure are presumed to be the factors influencing the resolution of growth increments (MacClintock, 1967; Pannella & MacClintock, 1968). Pannella & MacClintock (1968) suggest that the larger the angle between depositional surfaces and the structural elements of a shell layer the more evident will be the growth increments. Both oysters and mussels have an unfavourable angular relationship between growth increments and the margin of the shell (Pannella & MacClintock, 1968) and this may explain why the growth lines are difficult to observe. The present paper describes improved methods used to examine the internal micro478 growth patterns in the shell of the common musselMytilus edulisand reports on experiments to investigate the periodicity of the patterns.
Herring Investigations at Plymouth. V. The Plymouth Winter Fishery during the Season 1927–28
Authors: Ford E.
Published: May 2009

During the winter of 1927–28 the progress of the herring fishing at Plymouth was followed for the fourth consecutive season. A diary of market events was again kept by Mr. A. J. Smith of the Laboratory staff, while statistics of commercial landings and of the number of visiting drifters were kindly supplied by Mr. T. Edser of the Statistical Department, Ministry of Agriculture and Fisheries, and by Mr. E. C. Nelder of the Sutton Harbour Improvement Company, respectively. In the examination of age and growth of random samples of herrings, Mr. F. J. Warren, Laboratory Assistant, again acted as recorder. Details of the methods of treatment of the data collected will be found in Part I of this series of Reports (Ford, 1).
Herring Investigations at Plymouth. VI. Winter Herrings Caught off the Sussex Coast and in the Great West Bay during the Years 1924 to 1927
Authors: Ford E.
Published: May 2009

As explained in Part I of this series of Reports (Ford, 1, p. 238) it was thought that the study of herrings landed at other ports would provide information bearing upon the question of the origin and migrations of the shoals visiting Plymouth during the winter. The examination of the appreciable number of such samples obtained, however, has yielded results which are of interest in themselves, apart from their application to the question of the Plymouth fishery. In this paper, an account is given of the study of herrings landed at Hastings and Brighton from off the Sussex coast, and at Brixham from the Great West Bay. It is necessary to point out that the sampling was not specifically designed for such a study, so that due allowance for this fact must be made in drawing conclusions as to the progress of the local fisheries.
Herring Investigations at Plymouth. VII. On the Artificial Fertilisation and Hatching of Herring Eggs under known Conditions of Salinity, with some Observations on the Specific Gravity of the Larvæ
Authors: Ford E.
Published: May 2009

It has previously been shown (Ford, 1, p. 284) that herrings with fully ripened roes or milts form a considerable proportion of the landings by commercial drifters at Plymouth during December and January. Although naturally-deposited spawn has rarely been obtained from the sea-bottom in the district, the fact that newly-hatched larvæ occur in abundance provides evidence that actual spawning occurs locally. It has also been shown that from the end of September onwards, ripe fishes may be taken in stop-nets in Plymouth Sound, and even in sprat-seines in the estuarine waters of the River Tamar. A number of interesting and important questions is suggested by these observations. For example, do the ripe herrings which frequent the River Tamar actually spawn there, and if so, are they morphologically identical with those which spawn at sea, or are they of a different character? Would eggs deposited in the river be successfully fertilised and able to endure the periodic freshening of the water? Are the morphological characters of the offspring in any way dependent upon the environmental conditions under which they are developed?
On Methods of Reproduction as Specific Characters
Authors: Stephenson T. A.
Published: May 2009

1. Eight species of Actinians (enumerated on p. 148) have been specially studied with regard to their reproductive processes.

2. Among these forms five methods of reproduction occur—longitudinal fission; laceration by tearing; laceration by constriction; production of young viviparously; deposition of ova.

3. Deposition of ova may co-exist with any other method, except perhaps in certain viviparous forms.

4. Apart from this, one method only prevails in any one of the selected species—

A. Longitudinal fission inSagartia sphyrodetaandDiadumene luciœ.

B. Laceration by tearing inSagartia elegansandDiadumene cincta.

C. Laceration by constriction inSagartia lacerata.

D. Viviparity inSagartia troglodytesandCereus pedunculatus.

5. InSagartia anguicomaneither viviparity nor asexual reproduction occurs.

6. The viviparous forms studied do not reproduce asexually; nor are those which reproduce asexually viviparous.

7. In the experiments and observations of the author and of W. E. Evans, no exceptions to the above statements occurred. The question of exceptions is discussed on page 161.

8. Four of the above species were selected for regeneration experiments. Pieces were cut off from the margin of the base in each (artificial laceration).

9. InSagartia elegans(which lacerates naturally) it was found that nearly 100% of such pieces would regenerate easily; inS. laceratathe same was true in the best experiment.

10. InSagartia troglodytes(which does not lacerate naturally) only two pieces out of 76 regenerated fully, and the regenerative ability of the species appeared to be weak. InS. anguicoma, however, the percentage of pieces which regenerated fully (and did so strongly) was very much higher, though not reaching that ofS. elegans.
On the Cœlomic Cilia and Circulation of the Body-Fluid in Tomopteris helgolandica
Authors: Meyer Anton
Published: May 2009

The œcological significance of cilia and ciliary currents has been studied hitherto mainly so far as they are connected either with the epidermis or with the intestine. Epidermal cilia produce currents by which either the animal itself is moved or the surrounding medium is carried over the surface of the unmoved animal. In the latter case the ciliary currents serve for collecting substances, ordinary food and oxygen. It may be said, that the degree of specialisation of epidermal cilia generally indicates the degree of intimate dependence of the animal on its outside conditions (natural surroundings). (The cases where epidermal cilia are connected with sense organs are comparatively few.)
On the Occurrence ofEchinus esculentuson the Foreshore in the British Isles
Authors: Orton J. H.
Published: May 2009

Echinus esculentus, the larger common sea-urchin, occurs in the British Isles between tide-marks on rocky shores at about low-water spring-tide level in the localities given in Table I, page 292. It is, however, absent from apparently suitable foreshores in the Plymouth district, for reasons which are discussed in the present paper. Chadwick (1) states that “In Port Erin Bay it may be collected by hand on the beach, and on the ruined breakwater at low water of spring tides.” Elmhirst (2) records that “In this district (Millport)E. esculentusoccurs abundantly between tide-marks in spring and early summer on rocky coasts; a few may be found at almost any other season. About February or early March a shoreward migration seems to set in, so that in suitable weather conditions some hundreds may be collected at springs between April and June. Then their abundance decreases until about November,from when until January it is at a minimum.”
On the presence of vitellogenic substances in the starfish,Asterias rubens(L.)
Authors: Broertjes J. J. S. , de Waard P. , Voogt P. A.
Published: May 2009

Homogenates of pyloric caeca, gonads, spermatozoa and eggs from the starfishAsterias rubenswere fractionated by gel filtration chromatography.

It appeared that a glycolipoprotein fraction, present in oocytes and gonads of female animals, is absent in spermatozoa and gonads of male animals.

The possible role in vitellogenesis of this fraction and of a more omnipresent one is discussed.
The amphipod genus Aora in British and Irish waters
Authors: Myers A. A. , Costello M. J.
Published: May 2009

Aora spinicornis Afonso is recorded for the first time from the British Isles. Two species of Aora, A. gracilis (Bate) and A. spinicornis Afonso are now known from these waters. A. typica Krøyer, long considered a British and Irish species, is actually known only from the Southern Hemisphere. Figures and diagnoses of both species are provided together with a key to their identification.

Introduction

Lincoln (1979) records one species of Aora Kreyer from British and Irish waters. Due to an oversight (Lincoln, personal communication) he overlooked the paper by Myers (1973) (although listed in the bibliography) and attributed the single species to A. typica Krøyer, a species actually known only from the Southern Ocean between 20° S and 50° S (see Myers & Moore, 1983 which also includes a key to the world species). Two species of Aora are now known from the British Isles: A gracilis (Bate) which is widely distributed, and A. spinicornis Afonso, recently discovered in Lough Hyne, Co. Cork, and herein reported for the first time from these waters. This latter species has a Lusitanian distribution (Azores, Canaries, Mediterranean) and may occur in south-western England and Wales, but has been confused previously with A.gracilis (Bate). Both species have been described and figured by Myers (1973, 1982) and do not require further detailed analysis. However, since both species are now known to occur in these waters and are not both treated by Lincoln's widely used monograph, the two species are figured here as entire specimens (for details of appendages including mouthparts see Myers, 1982) and briefly diagnosed, and a key is provided to facilitate their identification by British and Irish workers.