bluuebunny/crossref_metadata_2025 huggingface dataset:
The Estimation of Zinc in Sea Water using Sodium Diethyldithiocarbamate
Authors: Atkins W. R. G.
Published: May 2009

Sea water contains very little zinc. Values from 0–73 mg. per cubic metre have been cited in Physics of the Earth, V, 180, Washington, 1932. According to Orton it is less than 0–1 parts per million in the English Channel. Dieulafait found 2 nig. and Bodansky 7–3, erroneously quoted as 73 above. The method described here permits of the detection of as little as 8 mg. per m3 using 200 ml. of distilled water in a Hehner tube, the delicacy of the reaction being much greater than that of any other for zinc. Sea water from the English Channel gives no turbidity and so is unlikely to contain as much as 8 mg. per m3. The method is brought forward on account of its usefulness in detecting and estimating zinc in sea water contaminated by contact with metallic surfaces. Its use in fresh water has already been described (Analyst, 1935, 60, p. 400, No. 711, June), and to this paper reference may be made for some possible sources of interference and for the origin of the reagent.
The Biology of Echinocardium cordatum
Authors: Moore Hilary B.
Published: May 2009

1. Monthly samples of Echinocardium cordatum were taken at Port Erin in 1932,1933 and 1934, and at intervals at Fairlie Sands in the Clyde.

2. Growth is continuous throughout the year with the exception of February-March. In their first winter the young urchins attain a length of about 10 mm. at Millport and 15–20 mm. at Port Erin. In their second winter they are about 20 mm. at Millport, and 30–35 mm. at Port Erin.

4. The year 1931 was cold and produced a very small brood of young urchins; 1932 and 1933 were warm years and produced very large broods.

5. The young settle below low water and migrate into the interval zone after an interval of four to twelve months.

6. The gonads of the young urchins mature in their second year. Spawning takes place in June–July–August.

7. The nutritive bodies in the ovaries are shown to be derived from the disintegration of relict ova.
Variations in the White Pigment of the Eye in Gammarus cheureuxi Sexton, with a Description of a New Genetic Type, the “Clotted eye.”
Authors: Sexton E. W. , Clark A. R.
Published: May 2009

A Great number of variations from the normal type have occurred in Gammarus chevreuxi during the course of the work carried out from 1912 until now.

In reviewing these variations it is convenient to class them according to the parts affected :

(1) Pigmentation of the body (3, p. 194).

(2) The Red retinal pigment of the eye (4, pp. 45–52).

(3) The Black retinal pigment of the eye.

(4) The white accessory pigment of the eye (2, p. 350).

(5) The structure of the eye, involving also the structure of the head (1, p. 274 ; 6, pp. 356–369).
The Biology of Balanus balanoides. V. Distribution in the Plymouth Area
Authors: Moore Hilary B.
Published: May 2009

1. The barnacles at five localities in the Plymouth area were examined as a check on the general application of observations made previously i n the Isle of Man.

2. The numbers and weights per square metre, and the mean individual weights, are given for a series of tidal levels for each locality.

3. The two “clean-water” localities agree substantially with the Isle of Man, except for the presence here of Chthamalus stellatus.

4. At the three localities where the water is rich in suspended matter first Chthamalus and then Balanus decreases progressively in numbers, but the latter increases very greatly in size, especially at low water.

5. The increased growth rate at low water, where food is abundant, is compared with the similar effect observed in wave-exposed conditions in the Isle of Man.
On a New Ciliate, Ptyssostoma thalassemae nov. gen., nov. sp., from the Intestine of the Echiuroid Worm, Thalassema neptuni Gärtner
Authors: Hentschel C. C.
Published: May 2009

The intestine of the Echiuroid worm, Thalassema neptuni Gärtner, is occasionally found at Plymouth to be infected with a small parasitic ciliate. I have searched the literature on the anatomy of Thalassema, but have been unable to find any reference to this Protozoon. In fact, I have not as yet come across any record of ciliates infesting the Gephyrea, though Mr. Dobell has informed me that, some years ago, the late Professor Ikeda mentioned to him the presence of ciliates from some of the Gephyrea he was then studying; but I have not been able to find any reference to ciliates in Ikeda's papers on Japanese Gephyrea. Lankester (1881), in a paper on Thalassema, merely records the occurrence of a gregarine which I also have observed in a number of specimens from the neighbourhood of Plymouth. I am, therefore, led to the conclusion that this ciliate must be new, and I have decided to name it Ptyssostoma thalassemæ nov. gen., nov. sp.
Food and Habits of Meganyctiphanes norvegica
Authors: Macdonald Roderick
Published: May 2009

1. Vegetable detritus of land and coastal origin is of notable importance as a source of food, especially to those specimens measuring 21-29 mm., which is the most abundant size found in the Clyde Sea Area.

2. Meganyctiphanes in the Clyde Sea Area for the most part lives and feeds between 10 and 20 fathoms above a muddy bottom, usually in waters about 60-80 fathoms deep.

3. Meganyctiphanes feeds by selecting from the surrounding water the suspended micro-organisms and detritus, and would thus come under the category of a “suspension feeder.”

4. The larger specimens measuring 29-31 mm. are found chiefly in Upper Loch Fyne. The largest specimens measuring 37 mm. are found exclusively in Upper Loch Fyne.

5. Adult specimens tend to decrease in numbers from May till September. During these months they appear to live during the day immediately above or on the muddy bottom.

6. The association of Meganyctijihanes norvegica, Thysanoessa raschii, Euchceta norvegica, and Calanus finmarchicus, in large numbers in Upper Loch Fyne would indicate that conditions there are specially favourable to all these species.

7. In Upper Loch Fyne M. norvegica, T. raschii, E. norvegica, and C. finmarchicus, make partial vertical diurnal migrations, specimens being found a few fathoms from the bottom during both day and night.

8. Under certain circumstances light appears to have a harmful effect on M. norvegica.
Studies on the Growth ofStichococcus BacillarisNaeg in Culture
Authors: Hayward J.
Published: May 2009

Stichococcus bacillarishas been grown under conditions of varying ionic concentrations. Sodium chloride appears to be the dominant compound in determining growth of this euryhaline alga and from the reaction to increased sodium chloride concentration it is postulated thatS. bacillarisis a freshwater organism which can tolerate high salinities. Some morphogenetic effects of high salinity are described.
A Revised Check-List of British Marine Diatoms
Authors: Hendey N. Ingram
Published: May 2009

The preliminary check-list of British marine diatoms first appeared in this Journal about 20 years ago (Hendey, 1954), and since that time many advances have been made in the study of these organisms. First, the known flora has been extended very considerably (Hendey, 1964, 1973) and much has been added to our knowledge of the structure of the valve by the use of the scanning electron microscope through the work of Hasle (1964, 1965a,b, 1972) and that of Ross & Sims (1970, 1971). This new information must inevitably lead to a reappraisal of views held on phylogeny within the group and consequently upon its systematic classification. While it would be premature at this stage to over-emphasize the importance of information gained in this way until a wider range of species has been examined, sufficient exists to support some minor changes and prepares the way for more radical changes that the new developments suggest. It should be pointed out, of course, that most of the ‘new information’ should more correctly be interpreted as confirmation of earlier views based solely on structure as seen in the light microscope of classical design and that some of the changes made in the classification as a result of these had been made many years previously, but the scanning electron microscope has enabled us to see more clearly the ultimate structure of the siliceous frustule of the diatom, thus permitting more positive decisions to be made regarding relationships and possible lines of descent.

At the First Symposium on Recent and Fossil Marine Diatoms held at Bremerhaven in 1970, Simonsen (1972) put forward some ideas for a more natural system of classification of the centric diatoms.
The Abundance and Distribution of Eggs and Larvae of Teleost Fishes off Plymouth in 1969 and 1970: Part 3. Eggs of Pilchard (Sardina Pilchardus Walbaum) and Sprat (Sprattus Sprattus (L.))
Authors: Demir Neclâ , Southward A. J.
Published: May 2009

Pilchard eggs were collected over a grid of 30 stations visited on 14 cruises from August 1969 to November 1970. The samples were taken with oblique tows of a 1 m terylene net at 4 knots, the average volume of water filtered being 750 m3. The formalin preserved eggs were graded into the series of stages described by Gamulin & Hure. No very early eggs were found, but from the occurrence of stage 2 eggs it is deduced that most spawning takes place in the early hours of darkness, between 20.00 and 24.00 h B.S.T.: some spawning must also occur all round the clock.

There were two main peaks of spawning, June-July and October-November, when large numbers of eggs were found inshore; the average numbers reached 196 per m2 water column in July and 30 per m2 water column in October. Smaller numbers of eggs were taken in the other months of the year, mostly offshore, and with a minimum in December–February. In the spring (March-May) the area sampled was well clear of the main area of spawning of pilchard in the approaches to the Channel, north or northwest of Ushant.

During the peak months no particular part of the sampling area appeared to be especially favoured for spawning.

The significance of the two main peaks of spawning is discussed in relation to the problem of recruitment of fish to the population. As an alternative to the accepted hypothesis that young pilchard move back to the Bay of Biscay for maturation it is suggested that some of them, at least, may survive and mature in the Channel.
The Occurrence and Significance of Tooth Cuts on the Blue Shark (Prionace Glauca L.) From British Waters
Authors: Stevens J. D.
Published: May 2009

In this investigation of the wounds occurring on blue sharks, tooth cuts were found only on females over 180 cm long, supporting the view that they are courtship scars incurred during breeding. However, it seems unlikely that these sharks normally mate in British waters. It is suggested that tooth cuts can provide information on the size at sexual maturity of the blue shark in European seas.
Sabellaria Colonies at Duckpool, North Cornwall, 1971–1972, With a Note for May 1973
Authors: Wilson Douglas P.
Published: May 2009

The exceptionally heavy settlement of larvae in the autumn of 1970 made it imperative to continue the observations of the previous ten years. This two-year extension has yielded much new knowledge about the growth of Sabellaria colonies at Duckpool, and about other aspects of their life. It revealed that the more densely packed the young were the faster their colony grew, provided conditions were favourable. In unfavourable circumstances close packing of young delayed growth. The rapid elongation of young tubes surrounding older tubes sometimes resulted in holes and fissures forming when the older worms failed to maintain all-round contact with surrounding young as the surface area of a colony increased. Such holes and fissures gave a false appearance of physical damage, and in colonies where they formed weakened the whole structure, becoming a factor in its ultimate destruction by wave action. Such fast-growing colonies have shorter lives than others growing more slowly and remaining more compact.
The Population Biology ofLacuna Pallidula(Da Costa) andLacuna Vincta(Montagu) in North-East England
Authors: Smith D. A. S.
Published: May 2009

L. pallidulais more or less confined toFucus serratus. L. vinctais common onF. serratusbut is also found onHalidrys, Laminariaand various Rhodophyceae. Neither species occurs in the absence of these weeds on which they both feed and spawn.Lacunaspecies are the dominant gastropods on weed at M.L.W.S. at Whitburn, County Durham.

Both species are annuals. InL. pallidulathe growth rates of females and males are markedly different, the former growing both faster and over a longer period. Females attain a mean maximum size of 8–4 mm compared with 45 mm for males.L. vinctamales and females grow at approximately the same rate, though females usually attain a greater size.

Males predominate inL. pallidulaat all times of the year, comprising between 55% and 75% of the population with a mean of 68–6%. Males die slightly sooner than females but there is no more than 4 weeks difference in longevity. Copulation inL. pallidulabegins in November and continues to April, with two peaks in January and March.

Spawning commences in January in both species and reaches its peak by April inL. pallidulaand by June inL. vincta. Hatching occurs inL. pallidulafrom April to July. The time of first hatching inL. vinctais not certain but is probably about March. Larval settlement occurs from June to October with a maximum in September.

Density is high following hatching inL. pallidula(> 2000/m2) and settlement inL. vincta(> 300/m2). Dispersion is similar in the two species, being aggregated at high density and more or less random at low density.
Behavioural and Secretory Activity during Tube construction byPlatynereis dumeriliiAud & M. Edw. [Polychaeta: Nereidae]
Authors: Daly John M.
Published: May 2009

The ‘mucous’ tube ofPlatynereis dumeriliiis made up of successive layers of fine threads held together by an adhesive secretion. Tube construction involves a regular sequence of behaviour which can be modified if algae or other objects are available for incorporation into the tube wall. Anterior parapodia are specialized for tube construction and gland cells producing tube components occupy most of the coelom in these segments. Several types of gland cell can be recognized histologically and those which form the threadsdischarge into a complex spiral organ below the cuticle.
The MedusaModeeria rotundaand its hydroidStegopoma Fastigiatum, with a Review ofStegopomaandStegolaria
Authors: Edwards C.
Published: May 2009

The hydroid of the medusaModeeria rotunda(formerlyTiaranna rotunda) has been found to be the thecate speciesStegopoma fastigiatum. The medusa has been obtained from the hydroid and reared to maturity. The stages of development of the medusa are described and figured, and its occurrence and habits are discussed. The affinities of the medusa are considered: it is shown to belong, together with the the genusChromatonema, to the family Laodiceidae.
A Taxonomic Appraisal of the two species of Stygiomedusa [Coelenterata, Scyphozoa], with the First Southern Ocean Records
Authors: Cornelius P. F. S.
Published: May 2009

Three specimens of Stygiomedusa fabulosa Russell, 1959, identified recently in the collections of the Zoology Department of the British Museum (Natural History) (Table 1) extend the recorded distribution of this infrequently collected genus to the Southern Ocean, and provide the opportunity of assessing the specific distinctness of S. stauchi Repelin, 1967. The specimens are the first of either species recorded from south of the tropics.
Brown Seaweed as an Indicator of Heavy Metals in Estuaries in South-West England
Authors: Bryan G. W. , Hummerstone L. G.
Published: May 2009

Concentrations of copper, zinc, lead, manganese and iron in the brown seaweed Fucus vesiculosus have been measured in samples collected over its range of distribution in four estuaries having different degrees of metal contamination. Factors controlling the concentrations in the weed have been studied and include the concentrations of metals in the water, seasonal changes, the position of the weed in the intertidal zone and the particular portion of the plant which is analysed. It is concluded that analysis of the weed gives a reasonable indication of average conditions in the water at points along an estuary and provides a method of making comparisons with the same estuary in subsequent years or with other estuaries.
Epibiosis in deep-sea crab populations as indicator of biological and behavioural characteristics of the host
Authors: Abelló P. , Villanueva R. , Gili J. M.
Published: May 2009

Incidence of epibiosis has been studied in the deep-water portunid crab Bathynectes piperitus in the Benguela upwelling region. The serpulid polychaete Spirorbis cf. patagonicus, the hydroid Stegopoma plicatile and the stalked cirripede Poecilasma kaempferi were the commonest epizoitic species. Analysis revealed some biological and ecological features of the host population: the species does not have a terminal moult; both sexes show different moulting patterns; sexual maturity occurs at around 35 mm carapace length; there is asynchronous moulting among different sub-populations in different geographical areas; burying behaviour appears to be not very widespread.
Mycteronastes undulatae gen. nov., sp. nov. (Monogenea: Monocotylidae) from the nasal cavities of Raja undulata in the eastern Atlantic
Authors: Kearn G. C. , Beverley-Burton M.
Published: May 2009

Mycteronastes undulatae gen. nov., sp. nov. (Monogenea: Monocotylidae) is described from the nasal cavities of Raja undulata caught off Arcachon in France and off Lisbon (Tagus estuary) and Sines in Portugal. Merizocotyle icopae Beverley-Burton & Williams, 1989, be-comes Mycteronastes icopae n. comb., the type species of Mycteronastes gen. nov. Similarities between M. icopae and M. undulatae include the arrangement of the haptor loculi and hooks, the general disposition of the reproductive system, the presence of eyespots and the habitat (the nasal cavities of the host). However, a distinctive feature is the absence of a copulatory sclerite and bulb in M. undulatae. The diagnoses of the following taxa are amended: Monocotylidae, Merizocotylinae and Merizocotyle.
A new mesopelagic appendicularian,Mesochordaeus bahamasigen. nov., sp. nov.
Authors: Fenaux R. , Youngbluth M. J.
Published: May 2009

An appendicularian belonging to the family Oikopleuridae, subfamily Bathochordaeinae,Mesochordaeus bahamasigen. nov., sp. nov., is described from a single specimen collected at mesopelagic depth in Bahamian waters. As the subfamily was founded with only one genus (Bathochordaeus), new descriptions are given for the subfamily and the two genera.
Dietary lipid changes during herbivory and coprophagy by the marine invertebrate Nereis diversicolor
Authors: Bradshaw Stuart A. , O'Hara Sean C. M. , Corner Eric D. S. , Eglinton Geoffrey
Published: May 2009

Changes in dietary lipids (fatty acids, sterols and fatty alcohols) during herbivory and coprophagy by the annelid worm Hediste (Nereis) diversicolor (O.F. Müller) were modelled in laboratory feeding experiments. The dinoflagellate Scrippsiella trochoidea (Stein) was used as the food in herbivory; faeces from the crustacean Neomysis integer (Leach) after feeding on this same alga, were used as the food in coprophagy.

Nereis is extremely efficient in its assimilation of dietary lipids and produces faeces with very low fatty acid:sterol (FAST) ratios in both herbivory and coprophagy. The net decrease in total lipid in both modes of feeding with this species suggests that annelids, where present, are as important as other invertebrate groups in affecting the flux of lipids through marine food chains.
The persistence and modulation of endogenous circatidal rhythmicity inLipophrys pholis(Teleostei)
Authors: Northcott S. J. , Gibson R. N. , Morgan E.
Published: May 2009

In constant conditions, freshly-collectedLipophrys pholisshow an endogenous circatidal activity rhythm, the initial activity peaks of which are phased to the expected time of high tide. The rhythm usually damps out over a few days but it may re-appear spontaneously or as a result of disturbance caused by handling and transfer to the experimental apparatus. The free-running period is more variable in fish kept in non-tidal conditions for prolonged periods than in those recorded shortly after capture. The non-circatidal periodicity shown by some fish may be the result of stable coupling in antiphase of desynchronised oscillators. There is no semilunar variation of the circatidal rhythm and no influence of the slight diurnal inequality in tidal period upon the rhythm's periodicity, at least at the site studied. The activity rhythm ofLipophrysvaries seasonally.
Structure, strength and seasonality of the slope currents in the Bay of Biscay region
Authors: Pingree R. D. , Le Cann B.
Published: May 2009

Slope currents in the Bay of Biscay show a consistent poleward transport but seasonal
trends and vertical current structure appear more variable. Indeed more long term records are required to establish seasonal trends firmly.

In the south of the region (Spanish slopes, mooring 118), the upper-slope (water depth 1005 m) flow exhibited a strong vertical structure with the maximum surface inflow
occurring in the winter period, and this effect may be wind induced. Satellite imagery
shows that this flow originates from the Iberian slope and that a decreasing along-slope
surface transport occurs along the north Spanish slopes at this time of year.

In the north of the region (Porcupine Seabight slopes) vertical structure was again
evident in the upper slope (~1000–m depth) flow. At mooring 114 the flow at mid–depth showed a weakening along-slope flow and an on-slope tendency in the March/April period; a complete reversal in the slope current occurred at mid–depths at the position of mooring 112 during March.

In the central region (Celtic and -Armorican slopes) seasonal variations in the upper
layers on the slopes were also present. In this region, the upper–slope transport (2500m depth) reached maximum values of 3–5 Sv in late summer. Upper flows at the rise (mooring 8002) were directed on-slope during the period of maximum upper–slope transport but changed direction in the March/April period.

In this region on the Celtic shelf (DB1), the surface flow is in a counter–current sense and wind-induced and so the seasonal variations here reflect seasonality in the wind stress.
Transfer of metal detoxification along marine food chains
Authors: Nott J. A. , Nicolaidou Artemis
Published: May 2009

It has been observed previously that the digestive gland of the carnivorous gastropod mollusc, Murex trunculus, does not accumulate metals which occur in high concentration in the digestive gland of its prey, the detritus-feeding gastropod, Cerithium vulgatum. It is proposed that mechanisms of metal detoxification which operate in C. vulgatum render metals biologically unavailable to M. trunculus. In the present work, this scheme is tested by feeding tissues containing detoxified metals from a gastropod, bivalve and barnacle to carnivorous gastropods. Metals in the prey are accumulated in insoluble granules in the digestive gland of the gastropod, kidney of the bivalve and gut connective tissue of the barnacle. These tissues are fed to the carnivores and the granules pass through the entire length of the gut. They are egested as clean preparations within the faecal pellets and they still contain the metals introduced by the tissues of the prey. This transfer of detoxification between species indicates that the food chain progression of material can result in the reduction of the bioavailability of metals. The observations are recorded by scanning electron microscopy and X-ray microanalysis.
Genetic population structure ofNeanthes succinea(Polychaeta: Nereididae)
Authors: Abbiati M. , Maltagliati F.
Published: May 2009

Two samples ofNeanthes succinea(Frey & Leuckart 1847) from the Mediterranean Sea were investigated. Twenty-one loci were analysed; seven of them were polymorphic in both populations. The level of heterozygosity was 2.2% and 4.4% in populations from the Tyrrhenian and Adriatic coasts respectively. The value of Nei's genetic identity index (1=0.965), together with the mean F(IT) (=0.350), shows that the samples can be considered reproductively isolated populations. F-statistics indicate that ME-1 is the discriminant locus between populations.
The costs of cell volume regulation: protein metabolism during hyperosmotic adjustment
Authors: Hawkins A. J. S. , Hilbish T. J.
Published: May 2009

To resolve the sources of amino nitrogen which is accumulated as intracellular solute during hyperosmotic volume regulation, components of protein metabolism were monitored during compensation for a change from 15 to 30% salinity in the blue mussel,Mytilus edulisL. Net solute gain stemmed primarily from a marked reduction in total output from the metabolic pool of free amino acids, most of this ‘saving’ resulting from slower whole-body protein synthesis, and the remainder from lower nitrogenous excretion. Indeed, total inputs to the metabolic pool of free amino acids actually decreased over the period of net solute gain at 30%. Associated contributions from dietary assimilation,de novosynthesis and the direct uptake of dissolved amino acids were each negligible, indicating that breakdown products from endogenous body protein were the only significant source of amino nitrogen accumulated during hyperosmotic regulation. This accumulation represented more than 3% of soft-tissue protein nitrogen within the whole animal. We therefore impress that the excretion, during hyposaline adjustment, of all nitrogen previously accumulated as solute in response to equivalent hypersaline change, represents a major component cost of cell volume regulation, and which helps to explain stress and even mortality consequent upon what may be small but frequent fluctuations of salinity.
Rapid shell closure in the brachiopodsTerebratulina retusaandTerebrataua transversa
Authors: Ackerly Spafford C.
Published: May 2009

Rapid shell closure in articulate brachiopods, occurring by a twitch contraction of the the ‘quick’ adductor muscles, is a response to disturbance or to physiological requirements of the organism. The relative simplicity of the closing system permits a detailed analysis of the functional architecture of the mechanism and the underlying principles of skeleto-muscular organization, in terms of (1) basic kinematic properties of the system (speeds and times of closure), (2) hydrodynamic reactions resisting closure, and (3) considerations of muscle physiology and mechanics.

Analyses of shell closure in the brachiopodsTerebratulina retusafrom the Firth of Lorn, Scotland, andTerebratalia transversafrom Puget Sound, USA, reveal (1) shell-closing times of the order of 50 to 70 ms, (2) closing velocities of the order of 3·5 radians s-1, from initial gapes of about 0·05 to 0·2 rad, and (3) muscle moment forces and hydrodynamic reactions with magnitudes of the order of 5 × 10-4N m (5 g cm). Muscle tensions developed in the ‘quick’ adductor muscle are of the order of 105N m2, and contraction velocities are of the order of one muscle length per second. Hydrodynamic reactions are a fundamental constraint on the closing mechanism, as determined by the concordance of actual closing events with predictions of a hydrodynamic model.
Distribution and rhythmic locomotor patterns of estuarine and open-shore populations ofCarcinus maenas
Authors: McGaw I. J. , Naylor E.
Published: May 2009

Populations ofCarcinus maenas(Crustacea: Decapoda) from an estuary and from the open shore were compared for salinity tolerance and rhythmic locomotor activity. Estuarine crabs were shown to be predominantly green; red and orange individuals were rare within the estuary in contrast to the open shore. Red crabs were less able to tolerate prolonged exposure to low salinity than green crabs. Spontaneous circatidal rhythms of locomotor activity were similar in red and green forms, but red crabs from the open shore reacted earlier, and were more active upon salinity reduction, than green crabs from the estuary which also showed rapid habituation to episodes of salinity change.
Observations on the ecology, behaviour, swimming mechanism and energetics of the neustonic grapsid crab,Planes minutus
Authors: Davenport John
Published: May 2009

Planes minutus(L.) (Crustacea: Brachyura) swims well (forwards only) but has limited endurance; at 28°C crabs swam at the surface for 35–45 min before sinking. The legs of the neuston crab are flattened and rotated into the ‘advanced’ orientation of the legs to the cephalothorax, characteristic of swimming brachyurans. All legs are involved in swimming; pairs 1 and 2 mainly support the crab in the water column, pairs 3 and 4 provide forward propulsion too. In leg-pair 4, the plane of extension and flexion is close to the horizontal and the leg provides lift on the recovery stroke. Plumose hairs are present on the anterior borders of the legs, adding to the propulsive area. Stout spines line the anterior and posterior margins of the legs; they allow the crab to hang upside down from floating substrata, but are also used to hold food items. The chelae ofPlaneshave cutting rather than crushing ‘teeth’. Crabs of the size studied (0·128−0·736 g wet wt) used oxygen (at 30°C) at about twice the rate when swimming (mean 1·014 ml O2g wet wt−1h1) as did resting crabs (mean rate 0·495 ml O2g wet wt−1h1). No oxygen debt is incurred during swimming. The mean crab density was 1·096 g ml−1(SD 0·060). Neustonic crabs would not move more than 5 cm away from their floating substrata to catch food. They show a novel ‘revving up’ procedure in which leg pairs 1 to 3 beat while the animal is attached to the substratum by spines on the tips of leg-pair 4. This allows much of the locomotor apparatus to overcome inertia and reach working speed, before an attack is carried out. Crabs ate postlarval and juvenile fish, euphausids, isopods, sea skaters and squid. Gelatinous animals were gener-ally avoided, though salps were captured and the stomach contents eaten.Planeswill take prey as big as itself and stores food for later consumption.
Physical factors affecting the fate of pedal mucus produced by the common limpetPatella vulgata
Authors: Davies Mark S. , Jones Hugh D. , Hawkins S. J.
Published: May 2009

Physical factors affecting the fate and functional capabilities of the pedal mucus ofPatella vulgataL. deposited in the intertidal have been examined. Mucus dehydration, rehydration and degradation were assessed. Mucus dehydration is dependent on ambient wind speed, temperature and relative humidity. Of these, over naturally encountered ranges, wind speed produces the greatest water loss over a 6-h period and it is surmised that mucus deposited at mid-shore will lose >60% of its water when exposed by the tide on days when the air is not still. The more dehydrated pedal mucus is, the longer it subsequently takes when immersed to reach a fully hydrated state.
Distribution of ichthyophonus hoferi (Mastigomycotina: ichthyophonales) in yellowtail flounder, Limanda ferruginea, from the Nova Scotia Shelf, Canada
Authors: Rand Thomas G.
Published: May 2009

A survey was conducted from 1986 to 1987 to determine the spatial and seasonal distribution patterns of Ichthyophonus hoferi Plehn & Mulsow, 1911 in marine fishes, especially yellowtail flounder, Limanda ferruginea, from the Nova Scotia shelf, Canada. Ichthyophonus hoferi was found in 56 of 6759 (0·83%) yellowtail flounder, in one of 613 (0·16%) haddock, Melanogrammus aelgefinus, but in none of the other 1485 fishes representing seven species sampled from this area. Within the yellowtail flounder population, the fungus was distributed in patchy manner with infection prevalence ranging from 0·4% at Banquereau Bank to about 13% at Brown's Bank. Infection prevalence was the same in both the male and female flounder. There was no apparent seasonal cycle in infection, although pathogen recruitment into L. ferruginea was from early summer through to early fall months.
Growth Irradiance as a Factor Controlling the Dark Respiration Rates of Marine Phytoplankton
Authors: Daneri Giovanni , Iriarte Arantza , Garcia Virginia M. , Purdie Duncan A. , Crawford David W.
Published: May 2009

Respiration rates normalized to chlorophyll a of laboratory cultures of Brachiomonas sp., Gyrodinium aureolum, Synechococcus sp. (clone WH 7803), Pycnococcus provasolii (clone W48–23) and Phaeocystis sp. showed a positive relationship with growth photon flux density (Ig). It is argued that this constitutes an energy conserving strategy of adaptation to conditions of low irradiance. The ratio of respiration to light-saturated rate of photosynthesis (R/Pmax) also showed a decrease with decreasing I. Algal cell size, within the investigated range (0·2 to 1380 pg C cell-1), showed little influence on biomass-specific respiration rates.
New Records for the Occurrence of Crenilabrus Bailloni (Osteichthyes: Perciformes: Labridae) in the Waters of Northern Europe
Authors: Wheeler Alwyne , Clark Paul
Published: May 2009

The capture of specimens of Crenilabrus bailloni Valenciennes, 1839 from Galway Bay, Republic of Ireland, and off the coast of Jersey, Channel Islands is reported. Occurrences of this species in northern European waters are discussed. It is concluded that this wrasse is a Lusitanian element in the northern fauna, and suggested that it may be more common in the fauna than records indicate due to its inhabiting a little collected habitat and on account of its similarity to the common corkwing wrasse C. melops (Linnaeus, 1758). Methods of distinguishing the two species are given.
Branchial Ventilation in the Burrowing Crab,Atelecyclus Rotundatus
Authors: Taylor A. C.
Published: May 2009

Atelecyclusburies itself by digging backwards into the sand, sometimes until only the antennae protrude above the sand. In this position it is difficult for the animal to maintain an adequate respiratory current through the branchial chambers by pumping water in the normal direction.

Studies of the ventilatory behaviour ofAtelecyclushave shown that, when on the surface of the sand, water flows through the branchial chambers as in most other crabs i.e. water enters the chambers at the base of the limbs and the exhalant water leaves anteriorly. This direction of flow is also maintained when the crabs are only partially buried but when more deeply buried, the direction of water flow is reversed by the reversal of the direction of beat of the scaphognathites and water is drawn down the antennal tube and leaves the branchial chambers at the base of the limbs.

InactiveAtelecyclusshow a well-defined rhythm of pumping in which regular periods of active pumping alternate with periods during which the scaphognathites stop beating and ventilation of the branchial chambers ceases. The rhythm of ventilation is regular but the duration of the ventilatory pauses (apnoea) may vary considerably between animals.

During pausing, the activity of the scaphognathites and of the heart are closely synchronized. The cessation of scaphognathite activity is accompanied by a period of cardiac arrest, although single heart beats may sometimes occur during a pause.

As in many decapods, the Po of the post-branchial blood was high (Pa, o = 92 torr, Pv, O = 21 torr) but during a pause P, o gradually declined.
The Structure of the Internal Tide at the Celtic Sea Shelf Break
Authors: Pingree R. D. , Griffiths D. K. , Mardell G. T.
Published: May 2009

Measurements at sea in the Biscay and Celtic Sea have shown that the peak to trough displacement of the internal tide maximises at the shelf break of the Celtic Sea with peak to trough values in excess of 50 m at spring tides during the summer. In this region the internal tide generated at the top of the slopes is highly distorted by the shelf barotropic tidal currents. The internal tide propagates on-shelf towards the coast and off-slope towards the ocean as a decaying progressive wave. A simple model is developed that illustrates many of the observed features of the measured structure of the internal tide.
Metal-Containing Blood Cells of Oysters: Ultrastructure, Histochemistry and X-Ray Microanalysis
Authors: Pirie Brian J. S. , George Stephen G. , Lytton David G. , Thomson John D.
Published: May 2009

The ultrastructure, histochemistry and X-ray microanalysis of the metal-containing blood cells in three species of oyster,Ostrea edulis, Ostrea angasiandCrassostrea gigasare described. Granular cells containing both copper (up to 400 mM) and zinc (up to 1 M) are present in all three species. In addition,Ostrea edulishas two other granular amoebocyte types which specifically accumulate either copper (400 mM) or zinc (12 M). In all types of amoebocyte, the metals are stored in membrane-limited vesicles. The ultrastructure and histochemical staining characteristics of the vesicular contents vary according to metal composition. Zinc-containing granules appear basophilic after sulphide treatment and display homogeneous electron density; copper/zinc-containing granules are less dense and show varying degrees of crystallinity; copper-containing granules appear crystalline (however, any acidophilic or basophilic reaction is masked by the dark brown precipitate of copper sulphide).
Factors Controlling Cold Tolerance and Breeding inBalanus Balanoides
Authors: Crisp D. J. , Lewis A. H.
Published: May 2009

Measurements during autumn and winter of the lower median lethal temperature of the barnacleBalanus balanoides(L.) under natural and modified environmental conditions in field and laboratory, show that the cold resistant state is advanced by three factors: short day photoperiod, reduced food assimilation and reduced temperature. Their relative efficacy is in that order.

These factors combine in promoting breeding and the acquisition of the cold tolerant state during autumn and winter. Although normally associated, breeding and cold tolerance are not mutually dependent; the one can be induced without the other under abnormal conditions.

Similar measurements made in the spring show that only a single factor is required to terminate the cold tolerant state — resumption of food assimilation. If feeding is discontinued in the spring, however, the cold tolerant state tends to return, but animals that have bred do not breed again until the following autumn.

Of the three well established mechanisms for seasonal cold tolerance — production of substances to cause freezing hysteresis, production of cryoprotective agents, and nucleating agents to promote freezing in the intercellular compartment — only the last can be entertained since the cold tolerant animal survives some 80% of the body fluids being converted to ice. The cold tolerant condition may also relate to higher levels of polyunsaturated fatty acids being present in the membrane lipid fraction in winter, so rendering cell membranes less prone to damage by ice crystals.

The suggestion is made that normal metabolic activity and tolerance of low chemical potential of water - the common factor in freezing and desiccation - are not compatible.
On the Status of the Deep-Sea Echinoids,Echinosigra PhialeandE. Paradoxa
Authors: Gage J. D.
Published: May 2009

Variation in morphological characters seen in a large collection of specimens of the genusEchinosigrafrom the Rockall Trough can be arranged in a continuous ontological series. This growth series embodied forms agreeing with Mortensen's (1907) descriptions of bothE. phialeandE. paradoxa.Bivariate biometrical study showed a well-defined allometric relationship of test length to other body dimensions, particularly the width of the ‘head’ and the width and height of the ‘body’. Immature specimens corresponded toE. phialewhilst the typically elongated ‘neck’ of adults corresponding toE. paradoxawas developed, along with the opening of the genital pores, at around a test length of 20–24 mm.
The Effects of Reduced Salinity on the Shell Growth of Small Mytilus Edulis
Authors: Almada-Villela Patricia C.
Published: May 2009

The shell growth of small coastal Mytilus edulis L. was measured at three different constant low salinities over short periods of time. Growth was significantly depressed in 6·4 and 16‰ S but not in 22·4‰ S. Fluctuating salinities between 0 and 32‰ S depressed growth whether the fluctuations were of sinusoidal or abrupt form. After 1 week of preconditioning to constant 32‰ S the growth of coastal (Bangor) mussels was better than estuarine (Conwy) mussels. However, after two weeks’ preconditioning to 32‰ S the estuarine mussels displayed the best growth. In the fluctuating regime, both coastal and estuarine mussels exhibited poor growth rates. The long-term response of the shell growth of coastal M. edulis was followed over a period of 44 days. Salinities in the range 1·8–9·6‰ S were lethal to the mussels within 10 days. In 12·8 and 16‰ S growth was initially delayed but recovered eventually. There was a gradual decline in the growth rate of the mussels exposed to the higher salinities (19·2–32‰) and an improvement in the growth of the mussels living in lower salinities (12·8 and 16‰) to levels nearly matching that of the high salinity animals by day 37. This suggests that acclimation of the shell growth of M. edulis to salinities in the 12·8–28·8‰ S range was achieved by the mussels during the experimental period.
The Benthos of a Marine Fly-Ash Dumping Ground
Authors: Bamber Roger N.
Published: May 2009

The benthic fauna of a fly-ash dumping ground off the Northumberland coast has been studied in comparison with that of the surrounding natural sediments and a designated offshore spoil ground. Continued ash dumping has resulted in an increase in the silt fraction of the sediments, together with the appearance of pozzolanic aggregates at the sites of greatest dumping, some 3·5 km offshore. The sediments here show a more rapid decline in Eh values with depth. The natural benthic macrofauna represented a typical Echinocardium-filiformis community, giving way throughout the offshore spoil ground to a ‘ Paraonis-Magelona’ community dominated by smaller polychaete species more tolerant of poor sediments, while the stations at the centre of the ash dumping showed an anomalous community structure. The density of the fauna was reduced at the centre of the ash dumping, the worst station yielding only eight individuals in 0·2m. Contours of numbers of macrofaunal individuals and species, of faunistic diversity and biomass, and of meiofaunal numbers all show a similar pattern of some depression along the spoil ground, and greater depression at the ash-dumping centre. Statistical analyses confirm a significant negative correlation between faunistic parameters and ash content. Deposit-feeding species represented a lower proportion of the community at sites of high ash content. The negative correlation between faunistic diversity and ash content was statistically significant over an area of 43 km around the centre of the dumping. The faunistic impoverishment is considered mainly to be a response to the dumping per se, and options for reducing this effect are discussed.
Calcification in the Shore Crab,Carcinus Maenas(L.): pH and the Precipitation of Carbonate From Sea Water and Blood
Authors: Digby Peter S. B.
Published: May 2009

Much evidence has suggested that calcification inCarcinusand certain other marine organisms may arise at least partly by the local formation of base. The extent of changes of pH needed to precipitate calcium carbonate from sea water or from the blood of the crab are not known with certainty. These have been investigated, using sea water and crabs from the coast of Maine.

Mean sea water pH, mostly as measured in aerated samples used for experiments in the laboratory, was 8·00, a little below the values commonly found close to the shore in summer. The corresponding mean blood pH was 7·12. Crushing calcified crab cuticle in sea-water raised the pH, showing the sea water to be below saturation with the salts concerned. The rise in pH was slightly greater in the more dilute suspensions, an effect attributed to the mixed composition of the calcifying salts. Thus in one group of experiments cuticle crushed in sea water in proportions 1:20 and 112·7 raised its pH by 0·66 and 0·62 units respectively, and extrapolation suggested that interstitial fluid of almost zero volume would equilibrate at 0·38 pH units above sea water. Crushing cuticle in crab blood in proportion 1:2·7 raised its pH by 1·03 units, showing the plasma also to be unsaturated with carbonate.

Carbonates were precipitated from sea water by rendering it alkaline with sodium hydroxide; in four experiments the first crystallites were found in samples in which in 3 days after addition of base pH had fallen to between 8·46 and 9·30. In a longer series of experiments with crab plasma, crystals were first seen in samples in which after three days the mean pH had fallen to 8–09. Crystallites at the surface formed mosaics of spherulites closely resembling those of normal crab cuticle.
The Food of Post-Larval Fish. No. II (1918)
Authors: Lebour Marie V.
Published: May 2009

Investigation of the food of larval and post-larval fish from the townets has been continued throughout the year (1918) in the same way as previously, by examining the contents of stomach and intestine in the fresh state. From May 24th a new big net made of stramin, with a wooden frame 36 inches by 25 inches, was used in addition to the ordinary tow-nets. Any live specimens, and these were chiefly caught in the big net, were kept in small aërated aquaria standing in running water and fed with plankton in order to see, when possible, what food they ate. In this way a few post-larval fish went through the metamorphosis into the adult form. Details of these will be found in another paper in the same number of the Journal (page 9).

The tow-nettings were regularly examined by Miss Webb in order to see whether the fish were feeding on what was commonest at the moment, and this was found to be usually the case, so far as the Copepods were concerned, although most of the young fish seemed to select their food to a certain extent. In any month the Copepods which are at that time commonest in the plankton are those most eaten by the young fish, but most of them have preferences and select in various degrees.
Thus in June Calanus finmarchicus and Acartia clausi were the commonest Copepods, Temora longicornis coming next, Pseudocalanus elongatus and Oithona similis not occurring so frequently. The commonest young fish in the tow-nets in the same month were the Whiting, Pollack, Rockling and Ballan Wrasse (Labrus bergylta).
The Young of the Gobiidæ from the Neighbourhood of Plymouth
Authors: Lebour Marie V.
Published: May 2009

Several Gobius species and also Aphya and Crystallogobius are common near Plymouth, from up the estuaries in the neighbourhood of Saltash to the west and Chelson Meadow to the east, as far as the open sea, well beyond Rame Head and the Eddystone Lighthouse. It has, however, always been difficult to determine the young of the various species as they usually differ very little from one another and it is hoped that the following notes may be a help in the elucidation of the subject.