bluuebunny/crossref_metadata_2025 huggingface dataset:
Marine algal zonation and substratum in Beer Bay, south-east Devon
Authors: Boalch G. T.
Published: May 2009

The intertidal zonation of the dominant algal species in Beer Bay, south-east Devon, was examined in relation to substratum by means of plane-table maps and transects. The dominance of Ulva lactuca on colonies of the reef-building worms Sabellaria alveolata was noted, but the distributions of Fucus vesiculosus, F. serratus, Gigartina stellata and Enteromorpha spp. showed no correlation with substratum.
The feeding and condition of plaice larvae in good and bad plankton patches
Authors: Shelbourne J. E.
Published: May 2009

In January and March, during the 1955 plaice spawning season, plankton samples were collected with a Heligoland larva net at stations on a grid around a floating radio buoy in the southern North Sea. There was a decided scarcity of suitable food for plaice larvae in the January patch, and this famine was reflected in the deteriorating physical condition of those larvae caught at the transition stage of development, when yolk reserves were becoming exhausted and an adequate external food supply essential. By March, the spring plankton outburst was in full swing. The condition of transitional larvae improved in this good food patch. Feeding started about the mid-yolk phase, mainly on plants. By the time most of the yolk had been resorbed, the appendicularians Oikopleura and Fritillaria had become the principal food items, and remained so throughout pelagic larval life.
Spectral composition of the light of Chaetopterus
Authors: Nicol J. A. C.
Published: May 2009

The spectral composition of the light of Chaetopterus variopedatus has been measured by means of spectral niters and multiplier phototube. Spectral emission extends from about 405 to 605 mμ, with a maximum at about 465 mμ. The spectral curve of Chaetopterus light is compared with a human visibility curve (scotopic vision), a visibility curve for Limulus, and an absorption curve for fish visual purple. Luminous efficiencies, based on these curves, are calculated.
Studies in the genus Fucus L. II. Distribution and ecology of forms of Fucus distichus L. emend. Powell in Britain and Ireland
Authors: Powell H. T.
Published: May 2009

The distribution and ecology of subspp. anceps and edentatus of F. distichus L. emend. Powell (1957) in Britain and Ireland is described in detail, based on recent ecological surveys and critical examination of all past records.

F. distichus anceps is a small form confined to certain very exposed coasts in the north and west of Scotland and Ireland, where it reaches the southern limit of its geographical range. This plant may be a relict form in Britain, existing now only under an extraordinarily narrow range of rigorous habitat conditions; it is not thought to be actively extending its range southwards at the present time. The ecology of subsp. anceps is considered principally in relation to that of other reduced fucoids found on exposed British shores, viz. F. spiralis f. nana and F. vesiculosus f. linearis; all three forms are illustrated by photographs and means of distinguishing them are described. The lifespan of subsp. ancepsis thought to be 2 to 3 years at some Irish sites, but may be longer at some of the Scottish sites.
Production and population dynamics of Ampelisca tenuicornis (Amphipoda) with notes on the biology of its parasite Sphaeronella longipes (Copepoda)
Authors: Sheader Martin
Published: May 2009

Ampelisca tenuicornis Lilljeborg, 1855, is a member of a widely distributed genus of benthic tube-dwelling amphipods. Population studies of A. macrocephala Lilljeborg in the Øresund show it to have a generation length of 2 years (Kanneworff, 1965), and A. vadorum Mills off Massachusetts, U.S.A., produces two generations per year (Mills, 1967). A. brevicornis (Costa) in the Mediterranean breeds throughout the year with a generation time of 5–7 months (Kaim-Malka, 1969), but has only one generation per year in Helgoland Bight (Klein, Rachor & Gerlach, 1975).
The integumental sensilla and glands of pelagic Crustacea
Authors: Mauchline J.
Published: May 2009

The pelagic environment can be divided into five gross regions. These are the intertidal and estuarine, the neritic and the oceanic epipelagic, mesopelagic and bathypelagic regions. Each of these regions has an endemic crustacean fauna but many species inhabit more than one region. The ranges and rates of fluctuations of environmental characteristics vary from the extremes encountered in the intertidal and estuarine region to the relative constancy of those in the bathypelagic region.
Absorption ofL-alanine and other dissolved nutrients by the spines ofParacentrotus lividus(Echinoidea)
Authors: de Burgh M. E. , West A. B. , Jeal F.
Published: May 2009

The possibility that marine invertebrates might obtain part of their nutritional requirements by direct absorption of dissolved molecules through the epidermis has recently received considerable attention. This revival of interest in a field which had been virtually abandoned since the early part of the century was led by the findings of Stephens & Schinske (1957, 1958, 1961). Modern analytical techniques have revealed that the amount of dissolved nutrients in coastal waters is much greater than was formerly realized; total amino acids have been recorded in concentrations of up to 10-4mole/litre in south-east Alaskan waters (Schell, 1974) and 7 x 10-5mole/litre off Helgoland (Bohling, 1970). Direct absorption of amino acids has been conclusively established in several phyla (see reviews by Stephens, 1968,1972), and one of the major aims of current research is to show that dissolved organic molecules taken up from available concentrations could be of nutritional significance. Recent developments concerning the possible roles of uptake in marine ecosystems have been reviewed by West, de Burgh & Jeal (1977).
The effect of swimbladder deflation on pressure sensitivity in the saithePollachius virens
Authors: Tytler P. , Blaxter J. H. S.
Published: May 2009

The saithe,Pollachius virens(L.), makes substantial diel vertical migrations like many other teleost fish. Adulst saithe offshore are known to ascent at dusk from 100 to 10 m (Schmidt, 1955) during which they experience a pressure decrease from 11 to 2 atm. If the swimbladders of these fish were fully adapted to the daytime depth, the gas of the swimbladder (which ‘obeys’ Boyle's Law) would expand 4½ times and rupture the swimbladder wall (Tytler & Blaxter, 1973). Even if not fullly adapted it is likely that some increase in volume would be experienced, giving not only the danger of the swimbladder bursting, but also a serious equilibrium problem as the fish become more positively buyant during the ascent. Jones (1952) for example suggested that the physoclistous perch adapted to a particular pressure could only cope with a 33% decrease in pressure without rising to the surface out of control.
The vertical distribution and succession of phytoplankton in the western English Channel in 1975 and 1976
Authors: Holligan P. M. , Harbour D. S.
Published: May 2009

The development of sensitive fluorimetric techniques for continuous in vivo measurements of chlorophyll ‘a’ (Lorenzen, 1966) has made it possible to study in detail the vertical distribution of phytoplankton in lakes and seas (e.g. Strickland, 1970; Berman & Pollingher, 1974; Lasker, 1975; Fasham & Pugh, 1976; Pingree et al. 1976). However, for marine environments there is little compatible data, such as given by Lasker (1977), on the species composition of localized phytoplankton populations. This is an important gap in our knowledge since the variations shown by different algal taxa in attributes such as nutrient requirements, growth rates, adaption to light, and palatability to zooplankton have wide ecological implications.
The ultrastructure and taxonomy ofDiacronema vlkianum(Prymnesiophyceae) with special reference to the haptonema and flagellar apparatus
Authors: Green J. C. , Hibberd D. J.
Published: May 2009

The taxonomic position of the golden-brown flagellateDiacronema vlkianumPrauser has hitherto been uncertain. It was first reported by Vlk (1938) from fresh water and a brief description given, particular interest being ascribed to the flagella which staining and light microscopy indicated to be without appendages. Because of this Vlk concluded that the organism, which he did not name, occupied a taxonomic niche somewhat apart from typical chrysophytes. In 1958, Prauser isolated, also from fresh water, a flagellate which he identified as Vlk's organism and he described it using both electron microscopy of shadow-cast cells and optical microscopy of living material. He confirmed the lack of flagellar hairs and discussed the taxonomy ofDiacronemain relation to both the Ochromonadales with heterokont flagella and the genusChrysochromulinaLackey with equal smooth flagella. He suggested that the genus could be thought of as representing a new family, the Diacronemataceae, arising from an ochromonad stock and possibly representing a unique line within the chrysomonads.
Endogenous circadian changes in orientational behaviour ofTalitrus saltator
Authors: Edwards Joan M. , Naylor E.
Published: May 2009

Orientated navigational behaviour inTalitrus saltator(Montagu) was studied throughout the diel cycle. Amphipods released at the centre of a circular arena without an artificial horizon on the periphery showed random escape directions at all times of day. In the presence of an artificial light/dark boundary the escape direction was random at night but was towards the boundary by day. The onset of significantly orientated navigation occurred just before the time of dawn and persisted in a typically circadian manner for 7 days in amphipods kept in continuous darkness.

The phase of the circadian rhythm could be reset in altered light/dark cycles. Phase changes were directly proportional to imposed L:D phases over the range —4 to + 12 h, except that shifts from —2 to +2 h induced no phase change in the orientation rhythm. The endogenous pattern of change of orientated navigation is discussed in relation to the nocturnal endogenous locomotor activity rhythm ofTalitrusand its diel pattern of foraging and burrowing behaviour on sandy beaches.
Correlation between cypris age, settlement rate and anatomical development inLernaeodiscus porcellanae(Cirripedia: Rhizocephala)
Authors: Høeg J. T. , Ritchie L. E.
Published: May 2009

The correlation between settlement rate, cypris age and anatomical maturation on the ultrastructural level was studied in female cyprids ofLernaeodiscus porcellanae, a rhizocephalan parasite of the porcelain crabPetrolisthes cabrilloi. There is no settlement on crabs until the cyprids are at least 2–3 days old, and maximum settlement activity is only reached 5 days after the moult from nauplius to cyprid (at 15 °C). Thereafter the settlement rate decreases again, possibly due to depletion of energy reserves in the non-feeding cyprids. Ultrastructural investigations show that the female cyprids cannot metamorphose into a kentrogon until 2–3 days after the moult from nauplius to cyprid, which explains the absence of settlement in young cyprids. Competence to metamorphose depends on changes in the cement glands, the epidermis and the antennules. The cypris moult cycle is arrested at an early stage and moult activity is only resumed after settlement. This ensures that the cyprids will not initiate metamorphosis while free-swimming.
The effect of β-alanine on the concentration of taurine and other free amino acids during osmotic stress ofMytilus galloprovincialis
Authors: Sansone G. , Cotugno M. , Cosma I. , Zatta P.
Published: May 2009

The effect of β-alanine on the concentration of taurine and other free amino acids (FAA) in different osmotic conditions inMytilus galloprovincialishave been investigated. Significant variation of the concentration of FAA as a function of the salinity have been observed.

β-alanine incorporation decreases the level of cysteic acid and taurine as well as the level of other FAA.
Continuous plankton records: the geographical distribution and seasonal cycles of decapod crustacean larvae and pelagic post-larvae in the north-eastern Atlantic Ocean and the North Sea, 1981–3
Authors: Lindley J. A.
Published: May 2009

The geographical distributions and seasonal cycles of pelagic larvae and post-larval stages of decapod Crustacea in the north-eastern Atlantic and the North Sea during 1981–3 are described from samples taken with the Continuous Plankton Recorder (CPR). Analyses of the distributions of 36 common taxa identified groupings which could be related to depth and temperature. The seasonal occurrences of planktonic larvae of benthic taxa were found to be correlated with sea-bottom temperature in the winter as well as parameters of the sea-surface temperature. Possible interpretations of these data are discussed.
The causes of buoyancy in eggs of marine teleosts
Authors: Craik J. C. A. , Harvey S. M.
Published: May 2009

Pelagic eggs and demersal eggs of teleosts both have osmotic concentrations similar to that of the maternal body fluids, less than half that of sea water. Pelagic eggs are buoyant because they contain such large quantities of this dilute aqueous fluid. While the demersal eggs of teleosts usually have a water content of 60–70%, the buoyant pelagic eggs of marine teleosts such as whiting, Norway pout, saithe, cod, haddock, turbot, dab, plaice, witch, long rough dab, halibut and sole typically have a very high water content (ca. 92 %) and a lipid content of 10–17% of egg dry weight. About 90% of the buoyancy of such eggs in sea water is caused by their high aqueous content, only about 10% being caused by lipid. The buoyant eggs of grenadier and ling have large oil globules and higher lipid contents, 27 and 35 % of dry weight respectively. Nevertheless, most of their buoyancy is provided by their high aqueous contents (89 and 81 % water). The high water content of pelagic eggs is brought about by a massive influx of water into the oocytes during meiotic maturation (ripening) after vitellogenesis but before ovulation. In cod and plaice, ripening is accompanied by a four- to five-fold increase in both water content and free amino-acids, and by a large influx of both potassium and sodium. In cod, free amino-acids contribute much more than these inorganic ions to the water influx and to the total osmotic concentration of the mature egg, but in plaice the relative contribution of inorganic ions approaches that of the free amino-acids.
The reproductive biology and the pathological changes of the plaice Pleuronectes platessa (L.) after the ‘Amoco Cadiz’ oil spill along the north-west coast of Brittany
Authors: Brule T.
Published: May 2009

The reproduction of the plaice has been studied in the North Sea (Wimpenny, 1949; Barr, 1963), in the eastern and western English Channel (Houghton & Harding, 1976) as well as in the bay of Douarnenez (Deniel, 1981). In 1972, Lahaye described the sexual cycle of the plaice caught in the Portsall area.

After the wreck of the ‘Amoco Cadiz’ off Brittany in March 1978, more diversified studies of this species were made to assess the effects of the oil spill on the plaice stocks in the contaminated area. In Lannion and Morlaix Bays, these fishes exhibited a clear decrease of growth, fin necrosis and an absence of recruitment in the population in 1978 (Desaunay, 1981; Maurin, 1984). In the Abers Wrac'h and Benoit, estuaries of the north-west coast of Brittany (Fig. 1) which were gravely affected by the oil spill, Haensly & Neff (1979) and Miossec (1981, 1984) noted a big change in reproduction. Conan & Friha (1981) observed abnormally low growth for plaice in Aber Benoit.
The distribution and abundance of bass (Dicentrarchus labrax) eggs and larvae in the English Channel and Southern North Sea
Authors: Thompson Brenda M. , Harrop Ruth T.
Published: May 2009

As well as being a popular sport fish, the bass (Dicentrarchus labrax L. 1758) is a valuable commercial species in England and Wales. In 1984 bass landings in England and Wales were estimated to have a first sale value of between £5–6 million (G. D. Pickett, personal communication). Concern has been expressed about the vulnerability of the stock to overfishing and to variability in recruitment, and there have been a number of studies of bass biology, distribution of the eggs and larvae, and of possible migratory movements of the fish during the adult phase, (Kennedy & Fitzmaurice, 1968, 1972; Kelley, 1979; Holden & Williams, 1974; Dando & Demir, 1985). This paper reviews the published data on eggs and larvae and presents new data on their distribution and abundance in the English Channel and southern North Sea between 1981 and 1984.
The ecology and reproductive biology ofCherbonniera utriculusandMolpadia blakeifrom the N.E. Atlantic
Authors: Tyler P. A. , Billett D. S. M. , Gage J. D.
Published: May 2009

The Molpadiida is an order of sea cucumbers identified by their stout body, the posterior region narrowing to simulate a tail and the absence of tubefeet. Typically they inhabit muddy environments from shallow water to abyssal depths. In the past the great variability in the taxonomic characters of this order has led to the formation of many genera and species (Heding, 1931, 1935), but more recently it has become apparent that many diagnostic characters change markedly during the life history of these holothurians and as a result fewer species are now recognised (Deichmann, 1940; Pawson, 1977). In a revision of the Atlantic molpadiids Deichmann (1940) recorded just three species from the north-east Atlantic (Molpadia blakei, M. musculusandHedingia albicans)with a further three species from the Arctic Ocean and Norwegian Sea (M. arctica, M. borealisandEupyrgus scaber). To these Sibuet (1974) added the new genus and speciesCherbonniera utriculusfound in the Bay of Biscay.
Modelling of a planktonic ecosystem in an enclosed water column
Authors: Andersen Valérie , Nival Paul , Harris Roger P.
Published: May 2009

The analysis of the complex trophic relations characteristic of plankton communities is much simpler in an isolated body of water than in the open sea. In fact, in the open sea physical processes make many biological phenomena difficult to recognize, and advection and turbulence generally make it impossible to sample repetitively the same population of organisms for long periods of time.
Reproduction and development of the sabellid polychaete Myxicola infundibulum
Authors: Dean D. , Chapman S. R. , Chapman C. S.
Published: May 2009

There are 290 described species in the tube-dwelling family Sabellidae (Fauchald, 1977), but our knowledge of their reproductive biology is limited, in whole or in part, to no more than 30 species (McEuen, Wu & Chia, 1983; Knight-Jones & Bowden, 1984). In the monogeneric subfamily Myxicolinae, the diminutive Myxicola aesthetica (=dinardensis) (Claparède) is known to undergo scissiparity (Caullery & Mesnil, 1920; Okada, 1934; Knight-Jones & Bowden, 1984). For the larger species, M. infundibulum (Reinier), the only information on reproduction is: an illustration of the sperm (Claparede, 1870), the conclusion that it spawns during the autumn in the Bay of Fundy and adjacent waters (MacKay, 1977 a, b), and that autotomy has not been observed and regeneration is limited to the branchial plume (Wells, 1952).
Notes on the growth and biology of the prawn Spirontocaris lilljeborgii (Danielssen)
Authors: Pike R. B.
Published: May 2009

Spirontocaris lilljeborgii is a dioecious species and no protandrous hermaphrodites have been seen.

The majority of males become sexually mature in the first year (7–9 months). Some of these may die after fertilizing the females and the majority die after fertilizing the females for a second year (18 months old).

Only a small proportion of the females breed in their first year, all breed during their second year and a few appear to live for a third year.

A first-year female lays from 130 to 160 eggs, and the usual output of a second-year female is from 450 to 650 eggs.

Egg laying begins at the end of November and hatching is complete by the end of March.

The total incubation period is about 90 days. Eye pigmentation first appears at about half the incubation period (47 days).

Juveniles can be distinguished as males and females by the shape of their pleopods within 4–6 months of hatching.
A note on the lipids ofBalanus balanusspermatozoa
Authors: Barnes H. , Dawson R. M. C.
Published: May 2009

Data are presented on the lipid composition ofBalanus balanusspermatozoa.

Lecithin is the major lipid and little plasmalogen is present.

The results are discussed in relation to what is known of other spermatozoa, both vertebrate and invertebrate.

Some data on the inorganic and organic constituents ofBalanus balanusseminal plasma have been given by Barnes (1962 a, 1963); lipids were shown to be present in the plasma and are a well-known constituent of the spermatozoa of other animals (Mann, 1964). In view of the relatively small amount of data on the detailed phospholipid composition of invertebrate spermatozoa the opportunity was taken during the investigation reported in the previous paper (Dawson & Barnes, 1966) to examine the spermatozoa ofBalanus balanus.The results are, however, best presented and discussed separately. The results are given in Table 1.
One hundred years of marine research at Plymouth
Authors: Southward A. J. , Roberts E. K.
Published: May 2009

The second half of the nineteenth century was a period of rapid change in the natural sciences in Britain, reflecting changes in social conditions and improvements in education. A growing number of naturalists were becoming socially conscious and aware of the need for a proper study of the sea and its products, following the success of the ‘Challenger’ Expedition of 1872–6. In 1866 the Royal Commission on the Sea Fisheries, which included among its officers Professor T. H. Huxley, one of the new breed of professional scientists, had reported that fears of over-exploitation of the sea-fisheries were unfounded, and had recommended doing away with existing laws regulating fishing grounds and closed seasons. Nevertheless, the rising trade in fresh fish carried to towns by rail or by fast boats (fleeting), and the consequent increase in size and number of registered fishing vessels, was causing widespread concern, and there were reports from all round the coasts about the scarcity of particular fish, especially soles. This concern was expressed at the International Fisheries Exhibition in London in 1883, a conference called to discuss the commercial and scientific aspects of the fishing industry, attended by many active and first-rank scientists. However, in his opening address Professor Huxley discounted reports of scarcity of fish, and repeated the views of the Royal Commission of 1866: that, with existing methods of fishing, it was inconceivable that the great sea fisheries, such as those for cod, herring and mackerel, could ever be exhausted.
The use of the dog-whelk, Nucella lapillus, as an indicator of tributyltin (TBT) contamination
Authors: Gibbs P. E. , Bryan G. W. , Pascoe P. L. , Burt G. R.
Published: May 2009

The term ‘imposex’ was coined by Smith (1971) to describe the superimposition of male characters onto unparasitized and parasitized females of gonochoristic gastropods. In Nassarius obsoletus (Say) the development of imposex results in the female having one or more of the following characters: (1) a penis with a duct leading to (2) a vas deferens which passes back to the ventral channel of the capsule gland and (3) convolution of the normally straight gonadial oviduct (Smith, 1980). Imposex in the similarly gonochoristic Nucella lapillus (L.) was first noted by Blaber (1970) who found females with penis-like outgrowths in Plymouth Sound populations. Subsequent studies (Bryan et al. 1986; Gibbs & Bryan, 1986) have demonstrated that the incidence and intensity of imposex have since increased markedly in the same populations and that the phenomenon is widespread around south-west England.
Size composition and seasonal changes in abundance of juvenile sole, Solea solea, in the Severn Estuary and Inner Bristol Channel
Authors: Claridge P. N. , Potter I. C.
Published: May 2009

During a period of five years in the mid-1970s, fish were collected at weekly intervals from the Severn Estuary and Bristol Channel. The resultant data on the abundance and lengths of these fish have provided valuable information on the times when the juveniles of several marine species are recruited into the estuary and on their pattern of growth during the first years of life (Claridge & Gardner, 1977; Titmus, Claridge & Potter, 1978; Claridge & Potter, 1983, 1984, 1985; Potter & Claridge, 1985). One of the marine species found in the Severn Estuary for which no seasonal data on density or body size have been presented is the sole, Solea solea (L.), whose relative abundance ranked it amongst the top ten species in two of the five years of our study (Claridge, Potter & Hardisty, 1986).
Estuarine species of Orchestia (Crustacea: Amphipoda: Talitroidea) from Britain
Authors: Wildish D. J.
Published: May 2009

The Talitridae are recognized as being difficult to identify (for example, Goodhart, 1941; Den Hartog, 1963) and it is thus not surprising that some species have been overlooked. Goodhart (1941) mentioned a new subspecies of Orchestia mediterranea Costa, 1853 which was not described, and the specimens are now lost (C. B. Goodhart, personal communication). During work on the biology of Orchestia in estuaries, two new taxa were discovered and tentatively given subspecific status (Wildish, 1969, 1970). Re-examination of the specimens in the British Museum (Natural History) and National Museum of Natural Sciences, Canada shows that both warrant specific status.
Development of the genital system in the copepodid stages of the calanoid copepod Temora stylifera Dana
Authors: Razouls Suzanne , Nival P. , Nival Suzanne
Published: May 2009

Within a cohort of young copepods, the individual size or growth rate becomes increasingly diversified during the development. The longer the development, the greater the resulting anatomical or functional diversity, since the differences between fast growing and slow growing individuals increase with time. Different factors may contribute to this variability, such as genetic diversity and metabolic differences in the ability to utilize food resources.
Belone svetovidovi Collette and Parin: a species of garfish new to northern Europe
Authors: Dorman Jeremy A.
Published: May 2009

Garfish (Beloniformes, Belonidae) are surface-dwelling, predatory fish characterized by elongate bodies and long beak-like jaws. Most are oceanic, but some species occur in estuaries and rivers. There are thirty-two species worldwide (Collette, 1982), of which until recently only one, Belone belone (L.) was known to be present in the waters of northern Europe. However, the existence of a second species, Belone svetovidovi Collette and Parin, was reported by Dorman (1984) from the south coast of Ireland. To date, thirty-one specimens of this fish have been captured in Courtmacsherry Bay, Co. Cork. This paper gives some details of these fish and how they may be distinguished from B. belone.
Observations on the ciliary currents of the jelly-fish Aurelia aurita L.
Authors: Southward A. J.
Published: May 2009

The jelly-fish Aurelia aurita possesses external and internal ciliary currents that play a large part in food collection and in the transport of food, reproductive products and excretory matter.

Adults feed on relatively small organisms, which are collected in mucus on all external surfaces and eventually passed to the inner surfaces of the oral arms.

The inner surfaces of the oral arms bear two ciliated tracts which operate simultaneously in opposite directions. The lateral tract carries food materials proximally towards the gastric pouches, but is capable of rejecting inedible matter. The basal tract carries excretory matter distally, away from the gastric pouches and canals to the exterior.

Rejection reactions are also found in the gastric pouches and radial canals, parts of which have currents moving in opposite directions on the roof and on the floor. These opposing currents appear to be derived from the system in the ephyra stage, where the circulation in the wide gastric cavity and blind-ending canals is maintained partly by centripetal currents on the floor and centrifugal currents on the roof.

The directions of the main currents remain constant throughout the larval stages to the adult, although slight variations are introduced by morphological changes. The currents also remain the same during spawning, when the eggs and sperm leave the gastric pouches by the normal excretory path.

Many of the ciliary currents found in Aurelia are present in other semaeostome and rhizostome medusae, but only in Aurelia do the umbrella surfaces and currents play a large part in food collection.
Phosphorus and silicon in sea water off Plymouth during 1954
Authors: Armstrong F. A. J.
Published: May 2009

The results of analyses of water from the International Hydrographic Station EI during 1954 are discussed. The seasonal variation is shown, in which it appears that consumption of nutrients in the spring outburst of plants was: phosphate 0.37μg atom P/l., total phosphorus 0.26μg atom P/l., silicate 2.49μg atom Si/1., these figures being means for the whole water column. Unusual changes in silicate concentrations between January and February,and between August and September, are ascribed to changes in the water mass at the station. This conclusion is supported by the temperature, salinity and phosphate.observations.
Notes on the variation occurring in Tubularia larynx Ellis & Solander
Authors: Hawes F. B.
Published: May 2009

As certain previous authors have observed, T. larynx is a species subject to much variation. Disregard of this has led to the erection of invalid species.

The descriptive characters used by Allman are discussed. In a comparison with material collected in Plymouth Sound these characters are shown to be so variable that used singly they are valueless. In particular, disregard of the stage of development and over-emphasis on size will be very misleading.

The causes of some of this variability are suggested.
Zinc Regulation in the LobsterHomarus VulgarisI. Tissue Zinc and Copper Concentrations
Authors: Bryan G. W.
Published: May 2009

Concentrations of Zn have been determined in the tissues of normal lobsters from sea water containing about 5μg/1. of Zn. The blood usually contains about 6 μg/g of Zn, mostly in the serum, while the soft tissues contain between 10 and 50 μg/g. Long exposure to sea water containing 100/μg.g/l. of Zn fails to alter the Zn concentrations of the blood, muscle and gonads, but increases the levels in the urine, excretory organs, hepatopancreas and gills. This result suggests that extra Zn is absorbed from high Zn sea water, possibly via the gills, and that two methods by which this is removed from circulation are by urinary excretion and absorption by the hepatopancreas.

Changes in the blood Zn concentration produced by injection are rectified quite rapidly in the same way. Injections failed to change the Zn concentrations of muscle and gonads.

Further experiments showed that Zn can be absorbed rapidly from the stomach and reaches the blood partly at least via the hepatopancreas. Again, this extra Zn is removed from the blood by urinary excretion and by absorption in the hepatopancreas. Eventual removal of Zn in the hepatopancreas probably takes place via the blood and excretory organs rather than via the gut. The role of the gills and gut in the regulation of the body Zn content has not yet been studied.
Blood Concentrations ofLimnoria(Isopoda) in Relation to Salinity
Authors: Eltringham S. K.
Published: May 2009

Freezing-point measurements were made of blood samples taken from specimens of the marine wood-boring isopodLimnoriathat had been exposed to sea water of various salinities for 2-3 days. Most of the work was done withL.(L.)tripunctataMenzies, but some preliminary experiements were carried out withL.(L.)lignorum(Rathke) andL.(L.)quadripunctataHolthuis.

It was found that the freezing point of the blood averaged 0·17°C above that of the external of medium in both hyp- and hyperosmotic environments. In the absence of any obvious factor which could explain this discrepancy, it is assumed thatLimnoriahas a certain degree of control over its blood concentrations.

Further experiments showed that the blood concentration fell as soon as the animal was introduced to the reduced salinity and levelled off at the hyperosmotic value within a few hours. There was some evidence of a periodicity in the osmoregulation.

The possible energetics of osmoregulation inLimnoriaare discussed and it is concluded that the amount of energy utilized in the process is unlikely to make any significant inroad into the energy resources available for boring activity.
A Comparison ofGadiculusfrom Scottish and Mediterranean Waters
Authors: Raitt D. F. S.
Published: May 2009

The original distinction between theGadiculuspopulations of the east Atlantic and the Mediterranean was made on the basis of differences in pigmentation and vertebral count found in the larvae. A comparison of adult fish from the two areas shows that there are significant differences in body dimensions and also in certain meristic characters, particularly vertebral count. These differences are briefly discussed.
Production and Survivorship of Epizoites of the Hydroid Nemertesia Antennina (L.)
Authors: Hughes R. G.
Published: May 2009

The survivorship of marine invertebrates that have a life span of less than 2 years is usually assessed by observing the decrease in abundance of animals from samples taken frequently throughout the life of an identifiable cohort or generation (e.g. Crisp, 1971). This method is only suitable for species with approximately simultaneous recruitment so that the animals can be aged with reasonable accuracy and the mortality before the end of the recruitment period can safely be ignored. Such age-specific survivorship data can be used to calculate secondary production by revealing the number of animals that reach successive weights (= Allen curves) (Crisp, 1971).
The Occurrence of Larval Anisakid Nematodes in small Gadoids from Scottish Waters
Authors: Wootten R.
Published: May 2009

Larval anisakid nematodes are among the most abundant helminth parasites of commercially exploited marine fish in the North-East Atlantic. Consequently, the biology of Anisakis and Phocanema in commercially sized fish from the North-East Atlantic has been quite extensively studied in recent years (see for example Davey, 1972; Rae, 1972; Young, 1972; Platt, 1975). There is, however, little available information on the occurrence of larval anisakids in small fish or species not used for human consumption. This is an important gap in our knowledge since information on the infection of such fish will increase our understanding of the circulation of these parasites within the marine environment and the levels of infection in commercial species.
Description of a New Species ofOligobrachia(Pogonophora) from the North Atlantic, With a Survey of the Oligobrachiidae
Authors: Southward Eve C.
Published: May 2009

Collections of bottom-living animals from the continental slope of the northern Bay of Biscay contain a new species ofOligobrachia; this increases the number of species ofOligobrachiaknown from the North Atlantic to five. Oligobrachiids are quite frequently found incubating embryos and five individuals of the new species carry embryos.Oligobrachiaembryos have been studied morphologically already (Ivanov, 1957, 1975; Southward & Southward, 1963; Brattegard, 1966; Ivanov & Gureeva, 1976) and should prove useful material for experimental studies in future. Incubation is also known in the family Siboglinidae, but neither embryos nor larvae have been seen in any other pogonophoran families. The Biscay collections also contain additional specimens ofOligobrachia ivanoviand these have been useful in revising the description of this rather rare species.
Effects of Feeding and of Chemical Stimulation on the Oxygen Uptake of Nassarius Reticulatus (Gastropoda: Prosobranchia)
Authors: Crisp Mary , Davenport John , Shumway Sandra E.
Published: May 2009

Nassarius reticulatus, like most other members of the Nassariidae and Buccinidae, is a scavenger. It apparently relies on the rapid detection and location of a food supply which is intermittently and unpredictably available. The olfactory reactions of Nassarius species are well-adapted for finding dead or damaged animals (Copeland, 1918). Stimuli indicating the presence of food provoke an impressive increase in activity of most starved Nassarius (Dimon, 1905; Copeland, 1918). Recently-fed whelks, however, often fail to respond to the same stimuli (Crisp, in preparation).
Possible Relationship Between Energy Metabolism of Muscle and Oxygen Binding Characteristics of Haemocyanin of Cephalopods
Authors: Zammit V. A.
Published: May 2009

The pronounced Bohr shift of cephalopod haemocyanin may be related to the formation of octopine, rather than lactate, by cephalopod muscle. Octopine is a much weaker acid than lactate.A highly pH-sensitive oxygen binding curve would permit the efficient unloading of oxygen at the tissues even for a moderately small decrease in venous pH.
Some Aspects of the Population Dynamics ofAsterina Gibbosa(Asteroidea)
Authors: Crump R. G. , Emson R. H.
Published: May 2009

Very few field studies of the population dynamics of starfish have been undertaken; such work depends upon being able to age individuals and identify age classes in the field. Information regarding growth rates in asteroids is notoriously difficult to obtain, due primarily to the absence of any method of assessing age, except where clear and obvious recruitment and regular growth provide size/age relationships. Numerous investigations of skeletal structures in asteroids by Smith (1940), Feder (1956), Hatanaka & Kosaka (1959) and Crump (1971) have failed to reveal any trace of growth lines similar to those found by Moore (1935), Jensen (1969) and Ebert (1970) in echinoids. In forcipulate asteroids, it is well established that growth depends primarily on temperature (Vevers, 1949; Hancock, 1958) and the availability of suitable food supplies (Mead, 1900; Galtsoff & Loosanoff, 1939; Smith, 1940; Vevers, 1949; Feder, 1956, 1970; Hancock, 1958). The food availability factor acts in such a way that it is impossible to tell the age of an adult starfish from its size; for example, in the spinulosan asteroid Patiriella regularts (Verrill), Crump (1969) found that specimens kept without food for 44 weeks lost 33 % of the original body weight, whilst P. regularts which had been fed on freshly killed crabs, showed a mean net increase of 629% of the original net weight over the same period.
Observations on Spatial Heterogeneity of Surface Chlorophyll in one and two Dimensions
Authors: Horwood J. W.
Published: May 2009

I trust that I will not be criticized for saying that, in general, the argument between Hensen and Haeckel has been resolved. Hensen (1887, 1895) believed that true spatial and temporal heterogeneity of the plankton could be resolved by careful measurement and analyses of variance. Haeckel (1893) thought these analyses might give more information than the data possessed. Our present understanding of spatial heterogeneity, and its analysis, does not lead us to disagree with either. Investigations carried out by a number of marine ecologists have shown large-scale spatial variations in phytoplankton. Amongst many others, this feature can be seen in studies off the northeast coast of England (Cushing, 1955), in the English Channel and Celtic Sea (Cushing, 1957; Pingree et al. 1976), off Scotland (Adams, Baird & Dunn, 1975,1976) and off the coast of the Netherlands (Gieskes & Kraay, 1975). Nevertheless the statistics of sampling heterogeneous distributions is far from simple, estimates of density for instance can be greatly influenced by the sample size (e.g. Greig-Smith, 1964; Cassie, 1963). Bainbridge (1957) summarized his review by saying that patches occurred on all scales from a few feet to as much as 30 or 40 miles by 120 or 180 miles. Our present understanding of the nature of turbulence in the sea would reduce his few feet to centimetres.
Generic Circumscription in the Family Ectocarpaceae (Phaeophyceae)
Authors: Russell G. , Garbary D.
Published: May 2009

The family Ectocarpaceae currently contains the simplest, and probably also the most primitive, members of the Phaeophyceae. The thallus form of every species is a heterotrichous filament with little or no structural modification. Some species may possess quite extensive cortication of axial filaments by adventitious rhizoids but advanced pseudoparenchyma is never formed. Periclinal cell divisions within filaments have also been reported, particularly in the course of sporangium development, but true parenchyma is unknown. Growth of the erect system of filaments is diffuse, for although intercalary sites of relatively active cell division may sometimes be observed, these lack the permanence of position and sustained activity of true intercalary meristems. The growth of the horizontal branch system is probably mainly apical, but is also too diffuse to be considered meristematic. Sporangia and gametangia are formed from vegetative cells and occur either as intercalary structures within filaments or as modified branch apices. Sexual fusion of gametes may be isogamous or anisogamous.
The Swimbladder of Deep-Sea Fish: The Swimbladder Wall is a Lipid-Rich Barrier to Oxygen Diffusion
Authors: Wittenberg J. B. , Copeland D. E. , Haedrich F R. L. , Child J. S.
Published: May 2009

The swimbladder of teleost fishes is a gas-filled sac which serves primarily to make the fish neutrally buoyant in sea water, but occasionally assumes other functions. The gas contained in the swimbladder is largely oxygen, at a pressure very close to the external hydrostatic pressure. The difference in gas partial pressure between the gaseous contents of the swimbladder and the blood and tissue fluids is large in fishes living at any considerable depth, for the hydrostatic pressure increases about 1 atm with each 10 m depth, while the partial pressures of gases in sea water and body fluids are relatively independent of depth and together give a pressure of only about 1 atm. The difference in partial pressure of oxygen alone across the wall of the swimbladder of a fish living at 3000 m depth is close to 300 atm.
Large-Scale Enclosed Water-Column Ecosystems an Overview of Foodweb I, the Final CEPEX Experiment
Authors: Grice G. D. , Harris R. P. , Reeved M. R. , Heinbokel J. F. , Davis C. O.
Published: May 2009

Enclosures of various sizes and configurations have been employed to maintain natural planktonic communities and to examine their responses to pollutants (e.g. Menzel & Steele, 1978; Steele, 1979). Studies on feeding, growth, and mortality of larval fishes, at times conducted in conjunction with pollution experiments, have also been successfully conducted in large enclosures (Koeller & Parsons, 1977). Implicit in these and other comparable studies has been the expectation (or hope) that a balance could be achieved between the advantages and difficulties inherent in more traditional field and laboratory studies. Field studies offer the realism of working with the natural assemblage with its many interacting components and links, but also suffer the disadvantage associated with a turbulent and advective system, which generally makes the repetitive sampling of the same populations impossible. Laboratory studies reverse the balance; control and definition of the components are gained at the expense of realism. The use of large containers represents a hybrid approach characterized by a partial control over a moderately realistic ecosystem. In the ideal case, the use of large containers allows sufficient control to permit experimental manipulation of (and the testing of hypotheses concerning) planktonic assemblages which are sufficiently realistic to permit extension of the experimental results to the ‘real world’.
The Reproductive Biology of the Ormer, Haliotis Tuberculata
Authors: Hayashi Ikuo
Published: May 2009

There is a long history of research on the ormer, Haliotis tuberculata L., in the Channel Islands. Stephenson (1924) was concerned with the reason for the diminution in the number of ormers off the shores of Guernsey and undertook a three months' investigation during the summer of 1923 and published brief notes on his results for further investigation. Tanner (1926) also made some brief notes on various aspects of the biology and ecology of the ormer which he said were based on 30 years' observation. In two reports (1929, 1937), Crofts dealt with aspects of bionomics, anatomy and early development of ormers with brief accounts of reproduction. Brehaut (1957) reported tagging experiments on the movement and growth of ormers and Forster (1967I gave more detailed information on these aspects, having earlier (1962) published a study on the quantitative measurement of the ormer population.
Structure and Growth of a Shore Population of the Ormer, Haliotis Tuberculata
Authors: Hayashi Ikuo
Published: May 2009

There are many Haliotis species which are widely distributed along the rocky coasts of temperate and tropical zones, most of them inhabiting the shallow sublittoral areas. Many of them form an important part of the fisheries industry in such countries as Japan, U.S.A., South Africa and Australia. In Guernsey, the Channel Islands, the ormer Haliotis tuberculata L. has been gathered as a local delicacy at low tide of good spring tides - locally known ‘ormering’.

Extensive tagging experiments have been undertaken at various places in the world for other species of haliotids, dealing with their growth and movement (Cox, 1962; Newman, 1966; Poore, 1972; Shepherd, 1973). For H. tuberculata, two tagging experiments, in which the growth and movement of sublittoral ormer populations were dealt with in detail, have been reported (Brehaut, 1958; Forster, 1967).

The present study has laid emphasis on the structure and growth of a shore population which has been the most important object of ormering to date.
Temporal Variations in Annual Production and Biomass in Estuarine Populations of two Polychaetes, Nephtys Hombergi and Ampharete Acutifrons
Authors: Price R. , Warwick R. M.
Published: May 2009

Production rates and production/biomass ratios have been estimated for a large number of macrobenthic species (Hargrave, 1977; Robertson, 1979). The usefulness of such estimates is limited by a lack of information on their temporal and spatial stability; we are aware of only one study (Sarvala, 1980) in which production has been estimated for more than one year. The present study investigates the stability of the production (P), biomass (B) and P/B values of two polychaete species, Nephtys hombergi Savigny and Ampharete acutifrons (Grube), over a 5-year period.
Tolerance of Intertidal Amphipods to Fluctuating Conditions of Salinity, Oxygen and Copper
Authors: Ritz D. A.
Published: May 2009

Bioassays designed to test the effect of single or some combination of environmental factors or pollutants on aquatic organisms are usually performed in constant levels of the imposed conditions and commonly in static rather than flowing water. The reason for this is usually one of convenience and practical simplicity and the results are valid for the set of conditions imposed. However, since aquatic organisms are rarely exposed to constant and static conditions, the results of such tests cannot with confidence be extrapolated to field conditions. This is particularly true in the case of estuarine organisms for which, change is the rule.