bluuebunny/crossref_metadata_2025 huggingface dataset:
A Seasonal Analysis of the Armoured Dinoflagellates of Loch Eriboll, North Scotland
Authors: Dodge John D.
Published: May 2009

The armoured planktonic dinoflagellates present at a site adjacent to a floating fish-farm in Loch Eriboll, North Scotland, were studied by surface net-sampling, mainly at two-weekly intervals, over a period of four years 1990–1993. A total of 62 species was recorded. Some dinoflagellates were present at all times of the year but they reached their lowest numbers in May, during the spring diatom bloom, and their highest numbers in mid-summer. There was usually a seasonal pattern in which the most abundant dinoflagellate during the early summer was the heterotrophic species Protoperidinium ovatum, and this was followed in the later summer by the autotroph Ceratium fusus. In 1993 the pattern was rather different, with Gonyaulax species abundant in June and, later in the year, both Protoperidinium cerasus and P. excentricum having periods of abundance. Potential toxin-producing dinoflagellates, Alexandrium tamarense (PSP) and Dinophysis acuminata (DSP), were found in small numbers.
Podoceru Chelonophilus (Amphipoda: Podoceridae) Associated with Epidermal Lesions of the Loggerhead Turtle, Caretta Caretta (Chelonia)
Authors: Moore P.G.
Published: May 2009

Examination of a small sample of Podocerus chelonophilus found clustered around mucus-exuding epidermal lesions of juvenile loggerhead turtles (Caretta caretta) collected off Madeira revealed the presence of fibrous material in the gut contents. The absence of planktonic remains suggested that these amphipods had been exploiting turtle material directly.

With the exception of the Cyamidae (whale lice), rather few amphipod taxa consistently live in association with marine vertebrates. Sea turtles, however, have been recorded carrying gammaridean and caprellidean epibionts by Caine (1986), who reported eight gammaridean species (including two domicolous fouling species) from nesting loggerhead turtles in Florida.
The growth and fruiting of Gracilaria verrucosa (Hudson) Papenfuss
Authors: Jones W. Eifion
Published: May 2009

Several workers have observed, in Europe and elsewhere, that Gracilaria verrucosa is a more conspicuous component of the flora in the summer months (Cotton, 1912, p. 134; Rosenvinge, 1931, pp. 602–6; Gibb, 1939, p. 378; Causey, Prytherch, McCaskill, Humm & Wolf, 1946; May, 1948), with the natural inference that its growth rate is greater in that season. However, the quantity present on the shore at any time depends also on the rate of defoliation by the waves. This will be higher in winter. Observation under more controlled conditions was therefore considered desirable.
A new species ofPlatidia(Brachiopoda) from the La Chapelle Bank region
Authors: Atkins D.
Published: May 2009

A new species ofPlatidia(Brachiopoda, Platidiidae) was dredged by R.V. ‘Sarsia’ in November 1956 in the La Chapelle Bank region, attached to the dead part of the coralAnisopsammia rostrata(Pourtales). Eight entire specimens and two smashed were dredged at position 47° 30′ N., 7° 20′ W. at a depth of 870 to 970 fathoms, and one at position 47° 38′ N., 7° 28′ W. at 710 to 750 fathoms. All, except the two smallest, were a reddish brown, the coloration being due to a deposit of manganese oxide: the natural colour is a yellowish white. The dead coral was almost black with the same deposit (see Southward, 1958, p. 644).
Movement receptors in decapod Crustacea
Authors: Wiersma C. A. G.
Published: May 2009

The sense organ ofCarcinus mamaslocated in the joint between the dactylo- and propodite possesses several types of sense cells (Wiersma & Boettiger, 1958). The most interesting types react to unidirectional displacement of the dactylopodite with equal sensitivity over the total possible arc of movement. Velocity has little influence on the discharges of the movement fibres since the maximum rate of firing is reached at a speed which is relatively little faster than the threshold. Fibres with marked differences in threshold are present for both extension and flexion. Other units in the organ react like conventional stretch receptors and give continuous discharges as long as the joint is near one of the extreme positions. Again different units are present for extension and for flexion. These position fibres are on the whole smaller than the movement fibres and their cell bodies have a more peripheral location in the organ.
Macrofauna production in an estuarine mud-flat
Authors: Warwick R. M. , Price R.
Published: May 2009

The importance of the extensive intertidal mud-flats to the energy budget of estuaries has frequently been stressed, but seldom quantified. Smidt (1951) has discussed the production of both macro- and meiofauna from the Danish Waddens in general terms but, because of the wide coverage, his information is not detailed enough to quantify annual production in terms of g/m2. The present study was designed to compare the productive importance of macrofauna and meiofauna in detail at a single site. This paper deals only with the first phase of this study, the macrofauna, which are retained on a 0.5 mm sieve for the major part of their productive life.
The bottom fauna of china clay waste deposits in Mevagissey Bay
Authors: Probert P. K.
Published: May 2009

The mining of china clay in Cornwall is an industry dating from the middle of the eighteenth century, and one which has grown to major prominence in the south-western peninsula, as illustrated by the historical accounts of Barton (1966) and Hudson (1969).

Present-day mining processes give rise to two main types of particulate waste. The coarser waste, or tip-sand, is deposited on land to form the massive white tips which characterize the scenery of the Cornish china clay mining areas, although small amounts may be used locally as a building aggregate. The finer-grained waste, known as micaceous residue, is produced in lesser quantities and is disposed of in a different manner.
Observations on diel behaviour patterns of North Sea gadoids in the pelagic phase
Authors: Bailey R. S.
Published: May 2009

The general biology of the gadoid fishes of the North Sea after recruitment to the demersal fisheries has received considerable attention, but little is known about their behaviour patterns during the period between metamorphosis and assumption of the demersal habit. In the summer of 1969 the Marine Laboratory, Aberdeen, began a series of annual midwater trawling surveys of the northern North Sea (Hislop, 1970, 1972a, b; Hislop & Bailey, 1971, 1975). During the surveys observations were also made on various aspects of the biology of the species caught. This paper describes the results of a series of trawling experiments carried out on a cruise of F.R.S. ‘Scarba’ (ex ‘Scotia’) between 12 and 29 August 1971.
Settlement of cyprid larvae ofBalanus balanoidesandElminius modestusinduced by extracts of adult barnacles and other marine animals
Authors: Larman V. N. , Gabbott P. A.
Published: May 2009

Crisp & Meadows (1962, 1963) have shown that aqueous extracts of whole barnacles, when applied to an inert test surface renders the surface attractive to barnacle cyprids thus simulating the gregarious response displayed at settlement. The factor responsible for promoting the settlement of cyprids ofBalanus balanoideshas been shown to be nondialysable, resistant to boiling in aqueous solution, and can be fractionated by precipitation with ammonium sulphate (Crisp & Meadows, 1962, 1963; Gabbott & Larman, 1971). In their 1962 paper, Crisp & Meadows showed that the settlement factor was present in untreated extracts of all the arthropod groups they examined (includingCarcinus maenas)and in extracts of two species of sponges and the fishBlennius pholis.Extracts of other animals and plants were not active. In particular, untreated extracts of the bivalvesMytilus edulisandOstrea eduliswere inactive when assayed against cyprids ofB. balanoides.Recently one of us has shown that boiled extracts, partially purified by precipitation with ammonium sulphate, of whole barnacles (B. balanoides, Elminius modestusandB. hameri), crab carapace(Carcinus maenas), whole heads of the blenny (Blennius pholis) and of the body tissues (excluding the shell) ofO. edulisandM. edulis, all contain a characteristic group of acidic proteins, or protein-carbohydrate complexes, with iso-electric points in the range pH 4.0–6.0 (Larman, 1975). This finding has prompted us to re-examine the specificity of the settlement response in barnacles.
Haemoglobin function inTerebella lapidariaL., an intertidal terebellid polychaete
Authors: Wells R. M. G. , Dales R. P.
Published: May 2009

Terebella lapidariaL. is a small terebellid common in crevices in the mid-littoral zone of rocky shores in the Plymouth area. The coelom contains abundant coelomocytes charged with haemoglobin in sufficient quantity to give the worm a brick-red colour.T. lapidariaalso has a discrete vascular system with haemoglobin dissolved in the plasma. When covered by the tide the worm irrigates its burrow intermittently. When revealed by the tide it cannot do so, and is then left in a thin film of water or in moist air for 3–4 h. We thought it was of some interest therefore to determine the oxygen equilibrium characteristics of these pigments.
Transfer of heat, fresh water and nutrients through the seasonal thermocline
Authors: Pingree R. D. , Pennycuick Linda
Published: May 2009

This paper estimates the turbulent transport of heat, fresh water and nutrients through the seasonal thermocline. In order to obtain a representative estimate of the annual variation it is necessary to average data obtained at a single position over a number of years. The number of years of sampling required depends on the particular parameter being studied. This can be seen by comparing the annual variation with the standard deviation, σ, for a specific month. This is analogous to the signal to noise ratio. For example, the annual range of temperature (or signal) is about 8°C for the water of the western English Channel. The variability of temperature in the same area (or noise) is about o.6°C. This figure is the standard deviation for the temperature obtained in a specific month at a fixed depth when data from a large number of different years are available. This variability can be attributed to a number of causes, to list a few; horizontal patchiness, local weather, advection, long term climatic changes. Hence for temperature the signal to noise ratio is about 13 and the annual pattern of events will clearly be established on the basis of monthly values obtained at a position during a single year.
The integumental organs of amphipods
Authors: Mauchline J. , Ballantyne A. R. S.
Published: May 2009

Some integumental organs of Amphipoda have been briefly described by Bate & Westwood (1863). Their diagrams are extremely small and, in some cases, inaccurate. Fleminger (1973) described the integumental organs of calanoid copepods of the genus Eucalanus. He shows that these are distributed over the body in a pattern peculiar to each species. Bate & Westwood do not mention patterns in the distribution of integu-mental organs in amphipods. They do, however, describe two peculiar structures in gammaridean species of the families Talitridae and Gammaridae; they do not mention these as occurring in any other families.
The glands of the larval foot in Pecten maximus L. and possible homologues in other bivalves
Authors: Gruffydd Ll. D. , Lane D. J. W. , Beaumont A. R.
Published: May 2009

A survey by Yonge (1962) of the byssal apparatus in the Bivalvia indicates that the formation of byssus is a larval characteristic which may or may not be retained in the adult. Some species such as the mussel, Mytilus edulis, retain the byssal attachment but have the ability to break the byssus and move over a limited area. Others, such as the scallop, Pecten maximus, lose the byssus entirely, become unattached and move by swimming. Yet others, such as the oyster, Ostrea edulis, relinquish all mobility at metamorphosis by cementing the shell to the substratum, and after metamorphosis lose all trace of the foot. Ostrea, Mytilus and Pecten therefore encompass a wide variety of life styles in the adult and are chosen as examples for detailed comparison of the byssus forming glands and other foot glands in the pediveligers.
Vitamin A compounds in the ovaries of the cod, Gadus morhua L., from the Arctic
Authors: Plack P. A. , Woodhead A. D. , Woodhead P. M. J.
Published: May 2009

Cod (Gadus morhua L.) from the Arcto-Norwegian stock that spawns off northern Norway were caught at various times during their gonadal maturation cycle over a period of 16 months. The ovaries were removed and either fixed for histological work or deep-frozen for the determination of vitamin A compounds.

The ovaries were inactive from June to September. Maturation began in late September-October and fully ripe eggs were present in February-March, the range of sizes being 500-650 /x. After spawning there was a period of resorption and regeneration, until May, followed by the quiescent summer period.

dry matter rose from about 16 to 29%; the total amount of vitamin A aldehyde, vitamin A esters and alcohol, carotenoids and lipids in the ovaries also increased, though the concentrations of the carotenoids and vitamin A esters + alcohol on a dry-matter basis fell. Vitamin A aldehyde was only found in maturing ovaries and in February, just before spawning, the weight ratio of aldehyde to esters + alcohol was about 10 to 1. The other substances were present in resting ovaries. The appearance of aldehyde in the ovaries occurred when there was histological evidence for the onset of vitellogenesis.
Differences revealed by paper partition chromatography between the gastropod Nassarius reticulatus (L.) and specimens believed to be N. nitida (Jeffreys)
Authors: Collyer Dorothy M.
Published: May 2009

The ninhydrin-positive patterns produced by chromatography of foot tissue of Nassariics reticulatus from Plymouth and North Wales and of specimens of Nassarius from Essex were established. The similarities and differences between the two are described and the consistent differences found are considered to be indicative of genetic differences between the specimens from Essex and those from the other two areas. The only factor found to affect the otherwise remarkably reproducible pattern given by individuals from the same area was the degree of starvation; the effect was reversible. The pattern given by another marine gastropod, Littorina littorea (L.), is also described. Reference is made to the potentialities of the technique.
The British species of Thracia (Eulamellibranchia)
Authors: Allen J. A.
Published: May 2009

Inspection of fauna lists suggests that many authors have found difficulty in identifying the British species of Thracia, most being content to list them as Thracia spp. Examination of museum collections and even keys to identification (Ziegelmeier, 1957) shows many errors of identification. The problem was brought to notice when some specimens dredged off the Northumberland coast appeared to differ from the five species recognized as occurring in British waters. It was decided that a study of the specific differences similar to that of Holme (1951, 1959) for Ensis and Lutraria, and Allen (1954) for Nucula, would be useful.

Specimens, particularly undamaged ones, of the British species of Thracia are difficult to obtain because they are both fragile and rare, and I am greatly indebted to the many people who were so kind as to give material and information for this study. These included Mr J. H. Barrett, Dale Fort Field Centre; Dr C. Burdon-Jones, Marine Biology Station, Menai Bridge; Mr I. C. J. Galbraith, British Museum (Nat. Hist.); Prof. R. A. R. Gresson, Queen's University, Belfast; Prof. L. A. Harvey, The University, Exeter; Mr N. A. Holme, Marine Biological Association, Plymouth; Dr N. S. Jones, Marine Biological Station, Port Erin; Mr A. D. Mclntyre, Scottish Home Department, Aberdeen; Mr R. McLaughlin, The University, Aberdeen; Dr R. H. Millar and Dr R. B. Pike, Scottish Marine Biological Association, Millport; Mr A. M. Tynan, Hancock Museum, Newcastle upon Tyne. I also wish to thank Dr D. A. Edwards, King's College, Newcastle upon Tyne, for assistance in matters mathematical.
Age, growth, and reproduction of the rock goby,Gobius paganellusL., in the Isle of Man
Authors: Miller P. J.
Published: May 2009

Age, growth and reproduction of the intertidal teleost, Gobius paganellus, has been investigated in the Isle of Man from March 1959 to September 1960. Samples were obtained by poisoning shore pools with a rotenone emulsion.

Age was determined by examination of otoliths where a translucent annual ring is laid down in spring. Although the potential life span is at least 10 years, immature fishes of the first two age-groups constitute most of the population. An onshore breeding migration is postulated. An empirical survival curve indicates a high mortality rate during the first two years of life. Instances of predation on G. paganellus are given.

Growth in length is logarithmic, with marked decrease in growth rate from about the age of sexual maturity. During the year, growth occurred from June to October. Maximum standard lengths recorded were 92*5 mm (feThe overall sex ratio of females to males was 1:1-326; this predominance of males persisted through the age-groups. The reproductive organs are briefly described, and a classification of gonad maturation is proposed. The breeding season lasted from mid-April to mid-June. Sexual maturity was reached at the end of the second or third year of life. Smallest ripening individuals found were 48-5 mm (female) and 505 (male). Fecundity increased with body size. Eggs were deposited on stones in shore pools and guarded by the male. Post-larvae occurred in pools from the beginning of July, and the first demersal individuals from August. Size-frequency distribution of oocytes in the ovary indicates that at least two broods may be produced in a single breeding season.

In maximum size, longevity, and age at maturity, G. paganellus differs from other European gobies so far studied. It is suggested that a similar life history is exhibited by other British species of Gobius. The short breeding season of G. paganellus in the Isle of Man is held to be a result of proximity to the northern limit of distribution of this species. Examples of this phenomenon in other teleosts are provided. The significance of pre-ovulatory corpora lutea in the ovary of G. paganellus is briefly discussed.
The spawning ofArenicola marina(L.) III. Maturation and shedding of the Ova
Authors: Howie D. I. D.
Published: May 2009

Experiments are described in which attempts were made to fertilize eggs of the lugworm taken from the coelom. These were unsuccessful except when the eggs were taken from spent or partially spent worms or from worms kept in the laboratory until they were about to spawn. It was concluded from this that maturation of the eggs precedes spawning but only by a matter of hours. That maturation begins in the body cavity was confirmed by histological examination of eggs from partially spent worms and criteria are given for the recognition of immature and mature eggs. Lack of success in previous attempts to fertilize coelomic eggs from non-spawning worms may be because females which are just about to spawn are not obtained by the normal methods of collection. It is suggested that this is due to a change in the behaviour of the worms associated with retention of eggs in the burrow after oviposition. With regard to the stimulation of spawning in female worms, it has been shown that maturation immediately precedes the onset of shedding. This, together with the fact that if eggs undergoing maturation are injected into a nonspawning worm they are shed automatically suggests that the primary stimulus for the onset of shedding is, simply, one which will induce maturation of the eggs.

Observations made during the above experiment together with the fact that worms can be induced to shed a few unripe eggs by injection of tissue extracts suggest, however, that spawning is not entirely passive and dependent on maturation. The lipid fraction of tissue extracts stimulates the active uptake of eggs from the coelom but it fails to induce maturation of the eggs and hence the free spawning produced in male worms. While the release of lipid into the body cavity may have some effect on the spawning of female worms (under natural conditions) similar to that previously suggested for males, it cannot provide the primary internal stimulus for spawning.
On the biology of the commoner gadoids in Manx waters
Authors: Nagabhushanam A. K.
Published: May 2009

The food and feeding habits, and general biology of the commoner gadoids in Manx waters have been studied. During the pelagic phase the diet of the gadoids showed a great similarity, consisting mainly of various abundant calanoid copepods. The larger pelagic post-larvae supplemented this basic diet with the inclusion of euphausiid ‘furcilia’ larvae and (in whiting) the amphipod Hyperia. Whiting, cod and pout were often found associated with medusae: the whiting, 21–53 nun long, were taken in large numbers, and their diet was found to be modified as a result of this association.

Young gadoids in a shallow sandy bay showed a great similarity in their basic diets, which typically consisted of various small, swarming mysids, amphipods and isopods. This habitat was a nursery area for many of the gadoids.

The larger fishes fell into two groups: (i) those that were characteristically feeders on the infauna and large, slow-moving epifauna; such fish being provided with stout barbels, well equipped with taste-buds, e.g. cod; (ii) those that feed largely, on the smaller active epifauna and nektonic prey, and possessed no, or only rudimentary, barbels, e.g. whiting.

The larger gadoids showed a concentration after spawning on a shallow, submarine shelf (the Warts Bank) to the south of the Isle of Man. Here the spent fish fed on an abundant and localized food, sand eels. The gadoids were found in this habitat from March to September, and were the object of a local fishery.

There was evidence that the gadoids exercised choice of food from that potentially available from the four primary food sources in each habitat; but if their favourite food was scarce or lacking, they would take substitute food by exploiting sources otherwise normally neglected.
Studies on reflexion of light from silvery surfaces of fishes, with special reference to the bleak, Alburnus alburnus
Authors: Denton E. J. , Nicol J. A. C.
Published: May 2009

The problem of how a fish can make itself invisible in the natural light-conditions in an aquatic environment is discussed with particular reference to the silvery surfaces of fish.

In fish which we have examined, the silvery surfaces are of two types: (1) an argenteum which consists of long thin crystals of guanine whose reflecting surfaces are approximately parallel with the surface of the fish; (2) layers of guanine crystals lying either on the inner surfaces of the scales or in the subdermis—these crystals are not, in general, orientated with their reflecting surfaces parallel with the surfaces of the fish, and are much broader than those of the argenteum.

Methods are described by which the orientation of the crystal planes with respect to the planes of the scales on which they lie can be determined.

The orientation of the crystals of type 2 in different parts of the body is described for the horse mackerel, Trachurus trachurus (L.), and for the bleak, Alburnus alburnus (L.).

For the bleak it is shown that although the planes of the crystals are often very much inclined with respect to the planes of the scales, the long axes of the crystals are always approximately parallel with the planes of scales. The inclination of the crystals, therefore, is away from the scales across their short axes.

Measurements of the light transmitted by silvery scales of the bleak show that they reflect light strongly when this falls obliquely on the crystals which they contain and that they are most transparent to light which strikes the scales in a direction perpendicular to the reflecting planes of the crystals.
Biometrical studies on some common cirripedes I. Balanus balanoides: measurements of the scuta and terga of animals from a wide geographical range
Authors: Barnes H. , Healy M. J. R.
Published: May 2009

A series of nineteen different biometrical characters have been measured on the scutal and tergal valves of the boreo-arctic Balanus balanoides collected from over its whole area of distribution; these values attempt to define the shape of the valves.
On some Copepoda from Plymouth, mainly associated with invertebrates, including three new species
Authors: Gooding R. U.
Published: May 2009

The adults of three new cyclopoid copepods are described and figured, namelyMicropontius ovoides, gen. et sp.nov., occurring on spatangid echinoids;Lichomolgus leptodermatus, sp.nov., andConchyliurus cardii, sp.nov., both associated with pelecypod molluscs.Micropontiusis made the type of a new family, the Micropontiidae.

Some other copepods,Asterocheres violaceus(Claus),Scottomyzon gibberum(T. & A. Scott),Pseudanthessius liber(Brady & Robertson),Bomolochus confususStock,Euryte longicaudaPhilippi var.minorT. Scott andPeniculus fistulaNordmann, are recorded for the first time from the Plymouth region; and mention is also made ofTisbe elongata(A. Scott).

Points of interest in the biology, morphology, systematics and distribution of all these are discussed.
On the behaviour of barnacles III. Further observations on the influence of temperature and age on cirral activity
Authors: Southward A. J.
Published: May 2009

The range of temperature over which the cirri were active, and the frequency of beating of the cirri at different temperatures were measured in a further five species of barnacles from a variety of habitats. In three of the species the temperature range and frequency of cirral beat were related to the geographical distribution of the species. The tropical and warm temperate species Balanus amphitrite was active at higher temperatures, and showed a greater frequency of beating than the northern species B. balanus; conversely, the latter was active to much lower temperatures than JB. amphitrite. The species with the widest geographical range, B. improvisus, showed cirral activity over the widest range of temperatures, although its behaviour at high temperatures was similar to that of the related species B. amphitrite. It is suggested that B. improvisus is a tropical species that has adapted itself to colder climates; its tolerance of a wide range of temperatures may be associated with its tolerance of low salinities.

The stalked barnacle Lepas anatifera showed too restricted a temperature range for its supposed world-wide distribution, and it is suggested that the species may contain physiological races adapted to different climates. The extremely restricted range of temperatures over which the cirri of the deepsea barnacle Hexelasma hirsutum were active can be correlated with the almost uniform temperature conditions at great depths.

In B. balanus age-groups can be clearly distinguished by growth rings on the shell, and the cirral frequency was found to be slower in the older specimens. Even slower cirral beating was found in some starved specimens.
Viability and glycogen reserves in the newly liberated larvae of Ostrea edulis L.
Authors: Collyer Dorothy M.
Published: May 2009

Samples of twelve broods of oyster larvae were subjected to a standard laboratory rearing technique while other samples were assayed for glycogen. The glycogen reserves of the larvae at liberation lay between 13·4 and 15·4% of the dry organic matter. No correlation was observed between the glycogen reserve and either the size of the larvae at liberation or the yield of spat in the rearing experiments
The breeding and fecundity of the Long Rough Dab Hippoglossoides platessoides (Fabr.) and the associated cycle in condition
Authors: Bagenal T. B.
Published: May 2009

Details are given of the breeding biology, including the fecundity, of the Long Rough Dab deduced from samples taken in the Clyde Sea area from October 1953 to April 1955. Where possible breeding is related to the condition of the fish; the index of condition is based on the length-weight relation.

The weight of Long Rough Dabs of each sex and stage in maturity increases as a power, slightly greater than the cube, of the length. An annual cycle of fluctuations of this power is seen in the immature females, and indicates how changes in condition at different seasons affect the different size-groups. The measure of condition is taken as the expected weight of a 20 cm Long Rough Dab, and the changes in this weight are followed through the sampling period for males and for immature, maturing and spent females. All groups tend to be in best condition during November and December followed by a decline to the spawning time, in March and April, after which there is a slow recovery.
Annual variations in fish fecundity
Authors: Bagenal T. B.
Published: May 2009

The variation in the fecundity of a fish species from year to year has not received much attention, although the changes in the numbers of young fish in the plankton are well documented for the Plymouth area (Russell 1930–47; Corbin, 1948–51). The most important work considering fecundity fluctuations is that of Simpson (1951) who, working onPlaice, Pleuronectes platessa L., concluded that during 1947,1948 and 1949 there was a steady decrease in the number of eggs laid, this being due to a decrease in the mean size of the spawning fish which he showed to be correlated with the egg numbers. Simpson's interest in the fecundity was to provide a more accurate estimate for determining the number of plaice in the total population from planktonic egg surveys similar to the work of Buchanan-Wollaston (1923). He did not consider in detail whether the fecundity for a given length might change from year to year. It is this problem which will be considered here. Estimates of fecundity of Long Rough Dabs, Hippoglossoides platessoides (Fabr.), will be analysed, and Simpson's Plaice data will also be considered.
Studies in the genusFucusL. I.Fucus distichusL. emend. Powell
Authors: Powell H. T.
Published: May 2009

The taxonomic status and nomenclature of the hermaphrodite forms of Fucus (other than the alga currently known asF. spiralisL. and certain hybrid forms) usually included under the nameFucus inflatusL. by European authors, but under several specific names by N. American and some other authors, is discussed. It is considered that the numerous forms described are best interpreted for the present as forms of a single, extremely plastic and widely distributed species.
The occurrence at Plymouth ofDictyocotyle coeliacaNybelin, 1941 (Trematoda: Monogenea)
Authors: Llewellyn J. , Green J. E.
Published: May 2009

In a sample of over 1000 rays belonging to four species of Raia examined at Plymouth between May 1955 and August 1956, the ‘very rare’ monogenetic trematodeDictyocotyle coeliacaNybelin, 1941 (total of four previous records) was found in the coelom of thirty-five out of 135 specimens ofRaia naevusbut absent from 478R. clavata, 420R. montaguiand 34R. brachyura.
The response of the limpet, Patella vulgata L., to waters of different salinities
Authors: Arnold D. C.
Published: May 2009

Patella vulgata gives a positive response to splashing with sea water or water of high salinity, and a negative response to fresh water or water of low salinity. The intensity of the positive response broadly corresponds with the salinity of the water used. There is a greater response to splash and a greater tolerance to reduced salinity in limpets from high-tide than in those from low-tide regions. A positive response is given to NaCl solutions of concentrations approximately equivalent to sea water, while a supra-normal response is given to concentrations somewhat above that of sea water. The perception of salinity is by receptors in the cephalic tentacles and mantle fringe.
Bio-assay of nitrogen available to two species of phytoplankton in an off-shore water
Authors: Harvey H. W.
Published: May 2009

A bio-assay of the nitrogen which was available to two phytoplankton species with their associated bacteria in an off-shore water is described.

The concentrations found by assay (11·5 and 13μg N/1.) were similar to the concentration of total inorganic nitrogen compounds found by analysis (10μg N/1.).

Of the organic nitrogen normally present in solution in sea water, an insignificant quantity appears to be available to the plant-bacteria community.
The determination of ammonia and total ionic inorganic nitrogen in sea water
Authors: Riley J. P. , Sinhaseni P.
Published: May 2009

Microdiffusion using a Cavett flask has been employed instead of vacuum distillation for the separation of ammonia from sea water; diffusion is approximately 75% complete after 24 h at 70°C. The recovered ammonia is determined by a modification of the phenate-hypochlorite method.

Raney nickel in the presence of ethylenediamine-tetraacetic acid has been used for the reduction of nitrate and nitrite to ammonia. The latter is separated by microdiffusion and determined colorimetrically. The method showed a coefficient of variation of 2·5% on a sample of sea water containing

No interference was encountered from a variety of organic nitrogen compounds.
George Atkinson 1885–1974 (M.B.A. Staff 1904–1910)
Authors: Hardy Alister
Published: May 2009

By the death of George Tatton Atkinson at Lowestoft on the 30th November, 1974, in his ninetieth year, the last link is broken with those famous pioneering days when the M.B.A. undertook, on behalf of the Government, the first official English fishery investigations by opening a special laboratory at Lowestoft in 1902 under the direction of Dr Walter Garstang. It is fitting that the life of George Atkinson should be recorded in our pages. Born in 1885 he came from a great sea-faring family and combined his love of the sea with an intense interest in marine natural history. As soon as he left school in 1904 he joined Garstang as an assistant working particularly on the biology of the plaice.
Seasonal variations in phytoplankton and glycollate concentrations in the Menai Straits, Anglesey
Authors: Hasan-Al R. H. , Coughlan, Aditipant S. J. , Fogg G. E.
Published: May 2009

It is now well established that natural phytoplankton populations may liberate a substantial proportion of the carbon fixed in photosynthesis directly into the external medium in the form of dissolved organic matter. Glycollate may be an important component of this extracellular organic fraction, both in culture (Hellebust, 1965) and in the natural environment (Watt, 1966). Nevertheless, it has been difficult to investigate the role of glycollate in the environment because of the lack of a convenient and reliable method for determining its concentration in natural waters. Shah & Fogg (1973) and Shah & Wright (1974), however, have developed a procedure for glycollate analysis in sea water, based on adsorption on to alumina and subsequent elution for determination by the Calkins colorimetric technique, which is both sensitive and not too laborious for routine analyses. Fogg (1966) suggested that glycollate excreted by phytoplankton acts as an extracellular reserve which may be utilized for survival under conditions unfavourable for photosynthesis. Wright & Hobbie (1965) showed that some fresh water bacteria take up glycollate at rates of the same order of magnitude as for acetate and glucose. Glycollate would therefore appear to be of importance in the energy flow between different trophic levels. In order to evaluate these hypotheses it seems important to determine the concentrations and turnover rates of glycollate occurring in natural waters.
Vertebral rings as a means of age determination in the blue shark (Prionace glauca L.)
Authors: Stevens J. D.
Published: May 2009

Elasmobranch fishes cannot at present be aged by scale or otolith readings as can certain teleosts. Consequently comparatively little is known about their age or rate of growth, particularly in the case of larger sharks. Alternative methods of age determination within this group have utilized tagging data (Bonham et al., 1949; Holden, 1972); size frequencies (Olsen, 1954; Aasen, 1966); the spine of Squalus sp. (Kaganovskaia, 1933; Holden & Meadows, 1962); tooth-replacement rates (Moss, 1967, 1972) and vertebral rings. These rings on the vertebral centra, resulting from variations in calcification, have also been used in the age determination of teleosts. In the scombroids there is often considerable variation in results even between authors working on the same species, mainly due to difficulty in interpreting the rings and deciding whether they are true year marks (Aikawa & Katô, 1938; Partlo, 1955; Otsu & Uchida, 1959; Hui-chong, Nose & Hiyama, 1965).
Observations during embryonic development in the genusDoto(Gastropoda, Opisthobranchia)
Authors: Kress Annetrudi
Published: May 2009

While working on taxonomic problems in the family Dotoidae and comparing the Mediterranean and Atlantic species (Schmekel & Kress, in the Press), it became apparent that very little embryological information was available for this group, other than that published by Alder & Hancock (1845–55), Pelseneer (1911), Miller (1958, Ph.D. Thesis, University of Liverpool) and Thompson (1967).

In the course of studies on the changes in egg-capsule volume in different nudibranch species (Kress, 1971, 1972) a fresh attempt has been made to obtain some comparative data on egg and capsule sizes and on the course and rate of embryonic development in the three species ofDotomost commonly found in the Plymouth area, namelyD. coronata(Gmelin, 1791),D. pinnatifida(Montagu, 1804) andD. fragilis(Forbes, 1838).
Analysis of the vertical and geographic distribution of the abundant species of planktonic ostracods in the North-east Atlantic
Authors: Angel M. V. , Fasham M. J. R.
Published: May 2009

Recent improvements in gear and techniques have permitted much more detailed studies to be made of vertical distribution patterns of pelagic oceanic organisms (Vinogradov, 1970; Foxton, 1972). One such development is the RMT 1 + 8 opening-closing net system for sampling plankton and micronekton (Baker, Clarke & Harris, 1973) which can be acoustically monitored in situ for fishing depth, water temperature, flow and net operations. This sampler has been used to study the midwater communities in the N.E. Atlantic over the last 6 years during cruises by RRS ‘Discovery’. It has been successfully operated to depths of 4000 m.
The relationship of the zoogeographic distributions of the planktonic ostracods in the North-east Atlantic to the water masses
Authors: Fasham M. J. R. , Angel M. V.
Published: May 2009

The quantitative zoogeography of pelagic zooplankton is a subject very much in its infancy. This is due to a number of causes; firstly, the taxonomy of a large number of animal groups has not been finalized and new species are still being regularly discovered. Secondly, many samples, especially from the earlier expeditions, were obtained from broad depth ranges and without accurate depth measurements or the use of opening-closing nets. This latter problem has been overcome by modern sampling devices (e.g. Baker, Clarke & Harris, 1973).

Underlying the thinking of a lot of previous workers has been the hypothesis that the water masses of the various oceans (usually delineated by means of temperature-salinity relationships (Sverdrup, Johnson & Fleming, 1942)) support a distinct fauna. This point of view has been summarized by Johnson & Brinton (1963), Banse (1964) and Beklemishev (1966, 1971). Examples of studies in which the relationship of species distributions to water masses have been studied are Pickford (1946; the cephalopodVampyroteuthis infernalis), David (1958,1963; chaetognaths), Bieri (1959; Pacific chaetognaths), Brinton (1962; Pacific euphausiids), McGowan (i960; the wormPoebius meseres) and Haffner (1952; the fish genusChauliodus). In the last case it was suggested that the oxygen content of the water was also an important factor.
Experiments with the behaviour of the bivalves Montacuta substriata and M. ferruginosa, ‘commensals’ with spatangoids
Authors: Gage John
Published: May 2009

The behaviour involved in the maintenance of the ‘commensal’ associations of Montacuta substriata and M. ferruginosa with spatangoids was investigated experimentally.

Both species are highly mobile when isolated from the ‘host’, and this activity was recorded through their mucous trails on glass plates, and photographically with a repetitive electronic flash system. Their responses were analysed mainly in a trough apparatus with a slow flow of water. The behaviour was resolved into responses to factors normally present in their environment. These included both gravity and water currents and a chemical influence from the ‘host’ spatangoid. M. substriata showed a marked negative geotaxis, while M. ferruginosa showed a similar response but of opposite sign. Pedal activity was stimulated as a kinesis to an unknown chemical ‘attractant’ from the urchin. The bivalves showed no specificity in this response since it was shown by both species to any of the spatangoids tested, regardless of the urchin species from which they were taken.
Preliminary studies on haemoglobin and other proteins of the Pogonophora
Authors: Manwell Clyde , Southward E. C. , Southward A. J.
Published: May 2009

Starch gel electrophoresis of extracts ofSiboglinum atlanticumshowed that all five individuals tested have two acidic haemoglobin components and a strong α-naphthyl acetate esterase. There was individual variation in the position of the esterase. Low levels of amylase activity were found in the extracts but no trace of dehydrogenases for such important substrates as glucose-6-phosphate, lactate, malate, and glutamate could be revealed by standard histochemical methods as applied to zone electrophoresis. The high level of haemoglobin and the protein peculiarities of the Pogonophora are discussed in relation to experiments on respiration. It is concluded thatSiboglinumhaemoglobin functions at very low oxygen partial pressures and that the high level of haemoglobin dissolved in the blood plasma of pogonophores does not reflect a high level of oxygen consumption or activity. The meagre biochemical data at present available on the Pogonophora do not favour relationship of this phylum to the echinodtrm-chordate line any more than to the annelids or other invertebrate phyla.

INTRODUCTION

Largely as a result of studies by A. V. Ivanov, the phylum Pogonophora has become recognized by zoologists in the past decade (reviewed by Hyman, 1959, esp. pp. 208–27; Ivanov, 1963; E. C. Southward, 1963). Pogonophores are small, extremely vermiform animals, living in tubes partly im-bedded in mud or muddy sand; while in some areas they are sufficiently abundant to dominate the benthic fauna, their occurrence at great depths has made living pogonophores very difficult to obtain.

Two especially interesting problems associated with this newly recognized phylum are:(a)Pogonophora are the only group of free-living Metazoa without a gut at any stage in their development, and thus, the method of feeding and type of metabolism has been the subject of considerable speculation;(b)Pogonophora possess a few characteristics—e.g. a ventral heart and dorsal nerve cord—suggestive of the echinoderm-chordate line of evolution.
The ciliary current of Phallusia [Ascidiacea] and the squirting of sea squirts
Authors: Carlisle D. B.
Published: May 2009

Filtration rates for Phallusia were computed from the rate of clearance of sus-pensions of colloidal graphite and of the flagellate Isochrysis. Rates varied from 825 ml./h to 5100 ml./h for animals between 8 and 128 g wet weight (40–336 ml./h/g wet weight; 88–570 ml./h/mg nitrogen). The greater part of this current is ciliary; less than 2 % is accounted for by squirting. Squirting thus plays but a minor role in maintaining the feeding current. Its probable function is perhaps more comparable with the expulsion of pseudofaeces in filter-feeding molluscs.
The hydroid and the medusaBougainvillia principis, and a review of the British species ofBougainvillia
Authors: Edwards C.
Published: May 2009

The hitherto unknown hydroid of the anthomedusaBougainvillia principishas been found in the Firth of Clyde, and medusae from it have been reared. The hydroid and the stages of development of the medusa are described and figured. The medusa is commonly present in the plankton in this area, and its seasonal occurrence is described.

The historical development of our knowledge ofB. principisand ofB. superciliaris, which have been confused, is discussed. The hydroid and the young medusae ofB. principisare shown to be identical with those described by Hartlaub and attributed by him toB. superciliaris.

Several doubtful speciesof Bougainvilliamedusae described from British waters are considered and are identified with accepted species.Medusa ociliaandM. duodeciliaare probably synonymous withBougainvillia pyramidataandB. principisrespectively; andB. nigritellais identified withB. muscoides, B. simplexwithB. principis, B. dinemawithB. britannica., andB. charcotiwithNemopsis crucifera, itself a probable synonym ofN. bachei.The medusaB. alderiis a probable synonym ofB. ramosa.

The hydroids and the medusae of the British species ofBougainvilliaare reviewed and compared; and records ofB. superciliarisandB. maclovianaare given.
The fine-structure and taxonomy of the haptophycean flagellatePavlova lutheri(Droop) comb. nov. (=Monochrysis lutheriDroop)
Authors: Green J. C.
Published: May 2009

Since its original isolation and description by Droop in 1953, ‘Monochrysis’ lutherihas proved to be one of the most valuable of cultured phytoflagellates. It has been used by many workers, too numerous to cite, in laboratory studies on phytoplankton growth kinetics, nutrition and biochemistry, and also in mariculture and animal feeding experiments, particularly experiments on the raising of crustacean and molluscan larval stages.
Observations with the scanning electron microscope on a filamentous bacterium present on the aesthetasc setae of the brown shrimpCrangon crangon(L.)
Authors: Shelton R. G. J. , Shelton P. M. J. , Edwards A. S.
Published: May 2009

In a previous paper, (Shelton, 1974) it was shown that the antennules and some other appendages of certain field and laboratory populations of the brown shrimp,Crangon crangon(L.), may become colonized by a filamentous organism tentatively identified as a blue-green alga. Other workers (Johnsonet al., 1971) have described similar growths on benthic Crustacea, fish eggs and algae (Bland & Brock, 1973) and have identified the epizooic organism asLeucothrix mucorOersted (Harold & Stanier, 1955), a filamentous, heterotrophic bacterium, common in the intertidal zone.
The macro-invertebrate fauna of the intertidal soft sediments of south east England
Authors: Kay D. G. , Knights R. D.
Published: May 2009

A study of the intertidal macro-invertebrate fauna of south east England was carried out as part of the investigations funded by the Department of the Environment of the likely ecological implications of the Maplin development proposals. The main aim of this study was to determine the potential food resource the invertebrate populations represent for the large numbers of wading birds which overwinter in this region. This article will concern itself solely with aspects of the invertebrate populations, the relationships between the waders and their invertebrate food supply will be presented separately (Kay, Blindell & Goss-Custard, in prep.).