bluuebunny/crossref_metadata_2025 huggingface dataset:
The Importance of Bacteria in Laboratory Experiments on Rearing the Larvae ofOstrea Edulis(L.)
Authors: Walne P. R.
Published: May 2009

Preliminary experiments had suggested that the extent of the development of the bacterial flora which develops when sea water is confined in small vessels is an important factor in the laboratory culture of oyster larvae. In the experiments reported in this paper the growth and settlement of oyster larvae was compared in controls of normal sea water with those in which the bacterial flora was controlled with antibiotics.

A concentration of 50 i.u. of the sodium salt of penicillin G per ml. suppressed bacterial growth for at least 2 days and, in a series of experiments using fifteen different broods of larvae, significantly (P>0·001) more spat were obtained in those to which penicillin had been added than in the controls.

A mixture of 50 units of penicillin G and 0·05 mg streptomycin sulphate was tried in three series of experiments. This completely suppressed the development of bacteria for at least nine days. In all three series many more spat were obtained than in the controls, but in only one series was there more spat than in the comparable penicillin experiment. It is suggested that when the bacterial population is very vigorous, or perhaps when certain species are present, this mixture will be more useful than penicillin alone. Experiments with other concentrations of penicillin, and with streptomycin and chloromycetin alone were not successful.
The Spread ofElminius ModestusDarwin In North-West Europe
Authors: Crisp D. J.
Published: May 2009

Material collected prior to 1940 indicates thatElminius modestuswas not present on British coasts at that time.

Elminiusincreased in abundance in south-east England from 1946 to 1950 and extended its range as far as the Humber, where it halted.

Its advance westwards along the south coast was similarly halted at Portland, but by 1948 independent colonies had been established in several of the river systems of Devon and Cornwall, in Milford Haven, and in the Bristol Channel.

The first populations in the Irish Sea were in Morecambe Bay. From thereElminiusspread rapidly south and west along the north coast of Wales, and more slowly north and west towards Galloway, eventually bridging the sea to the Isle of Man.

Detailed observations showed thatElminiusadvanced along the uniformly favourable north coast of Wales as a definite front moving at a rate of approximately 20–30 km per year. Around Anglesey where tidal currents were stronger it appeared simultaneously in many scattered centres.

A distinction is drawn between marginal dispersal taking place under the influence of normal agencies at the boundary of an existing population, and remote dispersal due to an artificial or freak transport over a long distance. In the case ofElminiusthe maximum distance that is likely to be bridged by marginal dispersal in the absence of strong residual drifts is about 30 miles.

Elminiusprobably first appeared near Southampton, and was introduced into the Thames estuary area probably by remote dispersal. Thence it spread along the east coast and was transported to Holland. Its extension into south Devon, the Bristol Channel, the Irish Sea, and to the French coast must also be attributed to remote dispersal.

The main ecological effects ofElminiusresult from competition for space withBalanus balanoides. SinceElminiusbreeds in summer, its dominance has a profound effect on the composition of the summer plankton, greatly increasing the number of barnacle nauplii, presumably at the expense of other larvae.
Survival of Anaerobic Periods By Two Intertidal Polychaetes, Arenicola Marina (L.) and Owenia Fusiformis Delle Chiaje
Authors: Phillips Dales R.
Published: May 2009

Measurements of glycogen in the body wall of Arenicola indicate that glycogen is consumed during anaerobic conditions. Estimations of lactate and pyruvate show that neither is accumulated, accounting for the absence of an oxygen debt previously found by other workers, and suggesting that glycogen breakdown leads to other acids. In Owenia most of the glycogen is stored in coelomic cells and these deposits are not drawn upon during anaerobic periods, yet this species can survive long periods without oxygen, apparently by becoming quiescent. Oil content in both species has also been measured, and was found not to fall under anaerobic conditions. It is suggested that survival of anaerobic periods may be mainly due to an ability to suspend normal activity.
The Oceanography of the Celtic Sea I. Wind Drift
Authors: Cooper L. H. N.
Published: May 2009

The dependence of prevailing wind drift in the Celtic sea upon prevailing winds is discussed and a proposal made to use wind records for the Scilly Meteorological Observatory for assessing drift currents for use in biological investigations.

If there is no seasonal change in the direction of the prevailing winds, nevertheless, the wind drift in summer will be more northerly than in winter.

The terms ‘current’, ‘residual water movement’ and ‘drift’, as used in this series of papers, are denned. The Ekman–Thorade equation for computing wind drift from wind is discussed and applied to the drift of the biological indicator Muggiaea atlantica in 1938. The two approaches agree to suggest that either method may be applied in biological distribution studies.

Some effects of drift, due to variable winds, on plankton distribution are outlined.
The Oceanography of the Celtic Sea II. Conditions in the Spring of 1950
Authors: Cooper L. H. N.
Published: May 2009

The circulation of the northern and north-eastern Celtic Sea, has been studied, using especially observations made in April 1950.

The Celtic Sea in that month was 0·5° C warmer than the average temperature 20 years earlier.

The following distinctive water masses have been recognized (i) Land's End water; (ii) South Wales coastal water; (iii) Carnsore corner current water; (iv) Nymphe Bank water, including a component enriched by up-welling off Waterford; (v) County Cork eddy water.

The South Wales coastal water, though rich in nutrients presumably derived from sewage effluents, was not very productive. A parallel is drawn with the Hyperion sewage scheme of the City of Los Angeles.

The low-salinity water present in the centre of St George's Channel in summer is attributed to flow from the coast of South Wales. In the autumn water is recruited more directly from the Celtic Sea.

The silicate content of the Carnsore corner current was half that in South Wales coastal water on the opposite side of the Channel.

Up-welling of water enriched by breakdown of bottom muds occurred off Waterford.

The drift system in the central Celtic Sea is dominated by the prevailing winds. The drift in April 1950 was a composite affair and it has been possible to dissect some of the components and to show how they interplay.

In about 7° W. long., a mixed water mass sets south from the Nymphe Bank and was identified for more than 100 miles.

A tentative explanation is offered for the distribution of compounds of phosphorus in terms of regeneration from bottom deposits.
Studies on Ectocarpus in Culture II. Growth and Nutrition of a Bacteria-Free Culture
Authors: Boalch G. T.
Published: May 2009

The growth and nutrition of Ectocarpus confervoides has been studied in bacteria-free cultures. Growth was estimated by dry weights determined under controlled conditions. A method for inoculation of cultures of filamentous algae is described and a table of culture media is given. Following a lag of 5–7 days there was a period of growth, which was not truly exponential, extending over a period of 35 days. Calculation of the relative growth constant for the early stages of growth indicated that the alga doubled its dry weight every 6–7 days. Cultures of Ectocarpus remained viable for over 1 year in the light and for over 100 days in the dark. In natural sea-water media the maximum growth was brought about by the addition of 0·5 mM potassium nitrate and 0·1 mM potassium phosphate. Ferric chloride had no effect on growth but additions of manganese chloride did cause some stimulation. Additions of some complex organic mixtures slightly increased growth but Ectocarpus was unable to grow on a range of organic carbon source in the dark. The optimum salinity at 20° C was somewhat higher than that of natural sea water but was apparently lower at 15° C. The optimum pH was 8·0. Light intensities between 1350 and 16,000 lux had no marked effects on the growth rate but did effect the lag, the optimum for this being 7000 lux. Temperature also had no effect on the growth rate but did effect the lag. The optimum was 15–20° C but there was growth between 10 and 25° C. A considerable range of artificial sea waters, with and without organic additions was investigated, in no case did they give a yield greater than two-thirds that in natural seawater media. These results are discussed in relation to other workers findings.
The Survival of Larval Fish in the Northern North sea According to the Quality of the sea Water
Authors: Fraser J. H.
Published: May 2009

The numbers of fish eggs and planktonic stages of fish taken during a 5-year period by the Scottish research vessels in the northern North Sea have been associated with the presence of Sagitta elegans and S. setosa in the same collections and over an 11-year period with the presence or absence of S. elegans. The results confirm Russell's findings in the English Channel that fish larvae are more abundant when S. elegans is present than when S. setosa is present.

The total numbers of fish eggs do not show these differences; spawning does not appear to be any more productive in water associated with S. elegans, rather the reverse, and this is shown to be so for the eggs of those species separately examined. Numbers of the larvae were distinctly greater in the ‘mixed’ conditions indicated by the presence of S. elegans and a more abundant food supply is a possible cause. That the differences may signify a more fundamental effect, however, is suggested by the figures for cod and haddock eggs, which show the earliest stages to be more abundant where S. elegans was absent although later stages were more abundant when S. elegans was present.
On the Pigment of Ianthina Janthina L
Authors: Comfort A.
Published: May 2009

The spectral absorption of the violet pigment extracted from dried Ianthina secretion by acetone is described. The colour of the secretion adsorbed on cellulose tissue is reasonably stable for purposes of transport. The pigment does not appear to be identical with the bilidiene-protein pigments of Aplysia, or with other violet molluscan pigments. The pigment of Ianthina shell is not extractable with acid, and all save that of the pellicle disappears on decalcification.
The Effect of Light on the Buoyancy of the Cuttlefish
Authors: Denton E. J. , Gilpin-Brown J. B.
Published: May 2009

The behaviour of well fed cuttlefish is strikingly affected by light. When the light is bright they usually bury themselves in the gravel at the bottom of their tanks, whilst after twilight they come out of the gravel and swim around until dawn.

Cuttlefish kept in complete darkness for one to two days usually become so buoyant that they are incapable of staying on the bottom and can only remain in mid-water with difficulty.

Animals kept in artificial light and dark showed changes in density which could amount to 2%. These changes come from changes in the volume of the gas space within the cuttlebone.

The density of the cuttlefish is largely governed by light intensity and there is little indication of an inherent diurnal rhythm of density change.

The rate of uptake of liquid when the cuttlefish becomes denser is such that it is unnecessary to assume that any active process is used to pump liquid into the cuttlebone. The cuttlefish must, however, extract liquid actively from the cuttlebone to become less dense.
Occurrence of Norway Pout, Trisopterus Esmarki (Nilsson) and Blue Whiting, Micromesistius Poutassou (Risso), in the Western English Channel off Plymouth
Authors: Southward A. J. , Mattacola A. D.
Published: May 2009

The small gadoid Trisopterus minutus (L.) is one of the most abundant demersal fishes on the Plymouth trawling grounds, though it is not retained in any number by the meshes of commercial trawls (Marine Biological Association, 1957). Correspondingly, the post-larval stages can be very numerous in the routine macroplankton collections at the Eddystone (Russell, 1973). However, in 1971 and 1972 T. minutus was accompanied by a few post-larvae of two other small gadoids, T. esmarki and Micromesistius poutassou (Russell, 1973,1976), and it was suggested that these might have drifted into the Plymouth region from spawning grounds farther to the west. A recent southerly shift in the main spawning region along the edge of the continental shelf was noted by Bainbridge & Cooper (1973), and Coombs (1975) has reported corresponding shifts in deep water species.
Correlation between Cadmium Concentration in the Water and Tissue Residue Levels in Dab, Limanda Limanda L., and Plaice, Pleuronectes Platessa L.
Authors: Westernhagen Hein Von , Dethlefsen Volkert , Rosenthal Harald
Published: May 2009

Although cadmium concentrations of unpolluted sea water are low, ranging from 0.01 to 0.41 µg/1 (Goldberg, 1965; Preston, 1973; Chester & Stoner, 1974; Kremling & Petersen, 1977) concentrations in estuaries are from 10 to 100 times higher, as reported by Butterworth, Lester & Nickless (1972) for the Severn and Eustace (1974) for the Derwent estuaries. Unusually high cadmium concentrations of 50 µg/1 have been found by Chan, Cheung & Li (1974) in Hong Kong harbour water. The cadmium in the drinking water (225 µ/l) and the food (rice) of Japanese farmers is believed to have caused the ‘itai-itai’ disease (Kobayashi, 1971), a pathological syndrome characterized by kidney damage with bone disease.
A Study of Retinal Development in Larval Herring and Sole
Authors: Sandy Jennifer M. , Blaxter J. H. S.
Published: May 2009

It is known from earlier work (Blaxter & Jones, 1967; Blaxter, 1968a; Blaxter & Staines, 1970) that the larvae of many species of teleost have a pure-cone retina. The rods only appear well after hatching and often as late as metamorphosis. This means that much of the larval life may be spent without fully developed eyes. The rods are difficult to resolve under the light microscope using paraffin sections (about 5 µm) and it is therefore easier to compare the number of cones with the prominent visual cell nuclei in the outer layer (ONL) in such preparations. The ratio has been found to be 1:1 in the early stages and changes as the rods develop, reaching ratios of 1:15 or more in adult fish. Thus, for every cone there may be 14 or more rods.
Host-Specificity and Speciation in Diclidophoran (Monogenean) Gill Parasites of Trisopteran (Gadoid) Fishes at Plymouth
Authors: Llewellyn J. , Macdonald Sheila , Green J. E.
Published: May 2009

The Marine Biological Association (1957) lists the poor cod Trisopterus minutus minutus (L.) (=Gadus minutus) as being parasitized by two monogenean gill parasites Diclidophora luscae and D. denticulata but at various times over the past 25 years we have, between us, examined the gills of upwards of 1000 specimens of T. m. minutus without ever having found a monogenean parasite. We concluded that the 1957 records were probably due to a misidentification of the hosts. However, in January 1979 one of us (J. E. G.) found several specimens of a monogenean very closely resembling D. luscae (Beneden & Hesse) on the gills of poor cod. D. luscae is normally found at Plymouth (Llewellyn, 1956) on only the pouting Trisopterus luscus (L.), a fish which from time to time is caught in the same trawl as T. m. minutus, e.g. in a total of 46 standard hauls between July 1976 and June 1978 (information supplied by Mr A. D. Mattacola), on 11 occasions (23%)T. luscus and T. m. minutus were caught together. On eight of these 11 occasions the lesser abundant of the two fish species constituted 10% or more of the combined total, and on three occasions the lesser abundant fish made up at least 40% of the combined total. Thus there is evidence that T. m. minutus and T. luscus from time to time occupy the same or neighbouring habitats (a standard haul may be over a distance of up to 8 km) and so presumably there has been opportunity for parasitic invasion from one species to the other to take place. That this has not in fact happened we have regarded as an example of the very strict species-specificity to their hosts manifested by most monogeneans and especially by diclidophorans on gadoids (Llewellyn & Tully, 1969). It was decided therefore to investigate how the sudden appearance in 1979 of a monogenean parasite on a previously uninfected population of poor cod may have come about.
Environmental Influence on Locomotor Activity inNephrops Norvegicus(Crustacea: Decapoda)
Authors: Moller T. H. , Naylor E.
Published: May 2009

Diel variations in the emergence of the burrowing prawnNephrops norvegicus(L.) have been investigated by direct field observations (Chapman & Rice, 1971; Chapman, Johnstone & Rice, 1975; Chapman & Howard, 1979; Atkinson & Naylor, 1976), and indirectly by sequential trawling during 24 h periods (Höglund & Dybern, 1965; Simpson, 1965; Hillis, 1971; Farmer, 1974; Atkinson & Naylor, 1976; Oakley, 1979). Peak emergence appears to be related to temporal and depth-dependent variations in daylight penetration, sinceNephropsare apparently nocturnal in shallow waters, crepuscular as the depth increases, and diurnal at the greatest depths of their occurrence. This lends support to the suggestion that emergence occurs at an optimum light intensity (Hillis, 1971; Chapman, Priestley & Robertson, 1972; Chapman,et al., 1975; Chapman & Howard, 1979). However, additional factors influencing emergence ofNephropsfrom their burrows have also to be taken in account, since laboratory studies of locomotor activity inNephropshave consistently revealed nocturnal activity patterns in light-dark (LD) regimes, with light inhibiting locomotor activity even at extremely low irradiance levels (Arechiga & Atkinson, 1975; Atkinson & Naylor, 1973, 1976; Naylor & Atkinson, 1976). Moreover, Hammond & Naylor (1977 a) have presented qualitative evidence that the nocturnal locomotor activity peak appears to be synchronized by falling light intensity at dusk. The differences between these experimental results and emergence patterns deduced from trawl catches and underwater observations ofNephropshave not been fully resolved by studies of the role of light intensity and of gradual light transitions (Arechiga & Atkinson, 1975; Hammond & Naylor, 1977 a,b). Thus the behavioural responses ofNephropsboth in the field and in the laboratory need to be assessed in relation to more accurately quantified light changes. Also, despite earlier evaluation of the problem (Atkinson & Naylor, 1976; Hammond & Naylor, 1977a) it is necessary to reconsider the possibility that the patterns of locomotor activity recorded in the laboratory are influenced by experimental conditions, as has been demonstrated for minnows (Jones, 1956), and flatfish (Verheijen & de Groot, 1967).
Cephalopod Beaks from the Stomachs of Two Northern Bottlenosed Whales (Hyperoodon Ampullatus)
Authors: Clarke Malcolm R. , Kristensen Thomas K.
Published: May 2009

This is the first detailed analysis of cephalopod beaks from the stomach of a northern bottlenosed whale,Hyperoodon ampullatus(Forster, 1770). The digestive action of many predators barely affects the chitinous beaks of cephalopods and some cetaceans accumulate the beaks in considerable numbers in their stomachs. The present beaks are clean and unbroken.

Identification of cephalopod beaks from stomachs of predators such as sperm whales (see Clarke, 1977), seals (Clarke & Trillmich, 1980) and albatrosses (Clarke, Croxall & Prince, 1980) throws considerable light on the biology and relative ecological importance of the species of cephalopods concerned as well as providing useful information on the diet of the predators.
A Note on the Free Amino Acids in Some Small Species of Pogonophora
Authors: Southward A. J. , Dixon D. R.
Published: May 2009

Previous studies on the significance of dissolved organic compounds in the nutrition of the smaller species of the phylum Pogonophora (Little & Gupta, 1968, 1969; Southward & Southward, 1968, 1970) were handicapped by lack of information about the levels of free amino acids in the tissues. In this brief note we give preliminary results for four species, using a modification of the technique described by Clark (1964, 1968, 1973) to estimate the amino acids in extracts of the whole body.
Physical Properties of Spermaceti Oil in the Sperm Whale
Authors: Clarke Malcolm R.
Published: May 2009

This is the second of three papers describing the structure, properties and buoyancy function of the spermaceti organ of the sperm whale (Physeter macrocephalus Linnaeus 1758). The first paper (Clarke, 1978a) described the detailed structure and proportions of the spermaceti organ and related structures and considered relevant details of the blubber, skin and lungs. Here, three thermal properties of the spermaceti oil are described which are relevant to a study of the function of the oil. Finally, in a third paper (Clarke, 1978b) it will be shown that, over its great geographical and depth ranges, the whale varies considerably in buoyancy due to variations in water density and the volume of air in its lungs and it is suggested that, during dives, the whale can control its own density by changing the temperature of the spermaceti oil of the head and may attain neutral buoyancy in dives deeper than 200 m.
On Balistiform Locomotion
Authors: Blake R. W.
Published: May 2009

Little is known about the swimming of fish in which flexures of the body and caudal fin are not the main means of locomotion. Breder (1926) provides brief descriptive accounts and a useful classification of the main non-body modes of locomotion in teleosts. These are discussed in general terms by Harris (1937, 1953), Marshall (1965, pp. 31–41) and Lighthill (1969).
Heavy Metals in the Burrowing Bivalve Scrobicularia Plana from the Tamar Estuary in Relation to Environmental Levels
Authors: Bryan G. W. , Uysal H.
Published: May 2009

The bivalve mollusc Scrobicularia plana (da Costa) is very common in the estuaries of South-West England and lives in permanent burrows in intertidal sediments ranging from soft mud to fairly hard sand and sometimes gravel. Although it obtains some of its food by filtering the overlying water, Scrobicularia is mainly a deposit feeder (Hughes, 1969). In addition to its widespread distribution, Scrobicularia has several features which make it attractive as a possible indicator organism for metallic contamination. It is more tolerant of low salinities than most common estuarine bivalves, usually penetrating farther upstream than Macoma balthica, Mytilus edulis and Cerastoderma edule (Percival, 1929; Spooner & Moore, 1940; Bryan & Hummerstone, 1977). Also, it lives for over ten years, usually attaining a length of 4–5 cm, and its rate of growth can be estimated from rings on the shell (Green, 1957; Hughes, 1970).
Racial Differences Between North American and European Forms of Balanus Balanoides
Authors: Crisp D. J.
Published: May 2009

After transplantation and acclimatization of populations of the barnacle Balanus balanoides from the coast of New England to the Menai Straits, differences in breeding behaviour persisted over a period of from 4 to 18 months. The two populations are believed to belong to distinct physiological races.

The New England populations fertilized 1½–3 weeks in advance of adjacent British populations.

Embryonic development in the post-cleavage stages of the New England population proceeded in vitro at about twice the rate of the development of the British population, under identical conditions.

The volume of the eggs of the New England population was 1.3–1.6 times as great as the volume of the eggs of the British specimens.

Both populations, when growing in British waters, liberated their nauplii in March at a time which coincided with the beginning of the vernal plankton increase in the locality. The embryos of the American population had therefore remained in the mantle space for a much longer period than had those of the British specimens and for a longer period than that reported for New England populations in their native habitat.

In B. balanoides the time of fertilization and rate of development may be genetically adapted in each general locality so that the embryos reach full term before the plankton increase is due. The actual time of liberation is then mediated by the hatching substance in response to prevailing food conditions.

If the B. balanoides population of the Western Atlantic area as a whole belongs to a physiological race distinct from that of the Eastern Atlantic, and responding differently to temperature levels at the breeding season, there is no reason to expect any close correlation in respect of environmental conditions between the southern limits of the species in Europe and in America.
Photographic Records of Living Oscular Tubes ofLeucosolenia VariabilisI. The Choanoderm Boundary, the Choanocytes and the Pore Arrangement
Authors: Jones W. Clifford
Published: May 2009

Some ecological data concerning the Plymouth species ofLeucosoleniaare given, together with a discussion of the speciation of the BritishLeucosolenia.

Oscular tubes ofL. variabilishave been photomicrographed at intervals, usually of 1 or more days. It was found that the choanoderm boundary at the proximal end of the oscular rim may advance, remain stationary, or recede in relation to the distal edge of the tube, according to the conditions. It may also move in either direction in relation to the spicules in its vicinity, regardless of how it is moving with respect to the oscular edge. The evidence indicates that the choanoderm is mobile on the inner surface of the tube and that the level of the choanoderm boundary is influenced by the surface area available and by the rate of multiplication of the choanocytes. The former depends upon the degree of contraction or expansion of the tube and the size and number of pores.

The arrangement of the choanocytes can alter within a few minutes. The cells, however, tend to cohere; their outlines near the base are polygonal and there is a thin hyaline layer separating the surfaces of adjacent choanocytes.

The beating of the flagella is uniplanar, the plane being perpendicular to the wall. The frequency of the beat varies from one choanocyte to another, as does also the orientation of the plane of beating. The latter does not alter when a current of water is drawn across the choanoderm. Excision of an oscular tube results in water flowing out at both ends as soon as the cut has been opened.
Sea Water, the Natural Medium of Phytoplankton II. Trace Metals and Chelation, and General Discussion
Authors: Johnston R.
Published: May 2009

Assays and mixed culture experiments prove that the supply of chelating substances is frequently the most crucial aspect of phytoplankton nutrition in sea water. Experimental results, theoretical considerations and tentative
calculations show that this supply is controlled by the stability of the trace metal chelates and in the sea may be mediated by certain unknown minor components of the dissolved organic matter.

The results of Parts I and II are considered together and show how seawater quality is closely related to the chelation of trace metals, mainly iron, and various other factors previously listed in the summary to Part I.
An Experimental Assessment of Some of the Characters Used for Specific Delimitation in the Genus Laminaria
Authors: Burrows Elsie M.
Published: May 2009

The growth in culture of Laminaria saccharina (L.) Lamour. and a species from Nova Scotia, tentatively identified as L. agardhii Kjellm., has been compared. Several characters, normally used for specific distinction within the genus Laminaria, have been shown to be modified by environmental
conditions. These all concern the lamina and include the following: general morphology and texture, the shape of the base, the anatomical construction and the presence or absence of mucilage canals.

The question of the identity of L. agardhii from eastern and western Atlantic coasts is discussed.
Photographic Records of Living Oscular Tubes of Leucosolenia Variabilis II. Spicule Growth, form and Displacement
Authors: Jones W. Clifford
Published: May 2009

When the oscular tube grows the spicules tend to separate from one another, but the separation is not uniform; local displacements of spicules occur with respect to other spicules in the vicinity. The same is found when the tube elongates while constricting, or changes shape in other ways. The spicule displacements reveal that the mesogloeal matrix is plastic. The spicules are probably anchored to the surface epithelia, the system of anchorage varying with time and from one spicule to another.

Small growing spicules may rotate through considerable angles and move relative to the fully grown spicules in their vicinity. The relative movements are most frequently towards the osculum. They are attributed to displacements of either the mesogloeal matrix or the internal epithelium, each relative to the other. They are not likely to be caused by the concerted amoeboid activity of the founder calcoblasts.

The monaxons tend to maintain their positions and orientations relative to the tri- and quadri-radiate spicules, apart from small localized displacements. Thus no significant movement of the pinacoderm relative to the rest of the wall could be deduced.

Fragments of broken spicules likewise tend to retain their relative positions and orientations in the spicule arrangement, though some moved or rotated by quite considerable amounts.

Spicules occasionally disappeared from the wall of some tubes. Monaxons were shed relatively easily, probably as a result of the spicule crowding associated with contraction of the tube. Some tri- and quadri-radiates were also shed through the pinacoderm. In some tubes spicule protrusion occurred at the oscular edge.
The Enumeration of Bacteria in Coastal Waters
Authors: Floodgate G. D.
Published: May 2009

The number and size of colonies found in bacterial counts of sea water collected from the Menai Straits varies with the concentration of peptone in the medium. The optimum concentration of peptone was found to be 0.3%. Neither yeast extract, beef extract or added iron increased the count when added to media made from Menai Straits water. The effect of various temperatures on the count, and the relative merits of pour plates and surface growth techniques were examined. Vigorous shaking, or passage through a Sharpies centrifuge, was found to increase the count.
On Some Environmental Factors Affecting the Distribution ofCirriformia Tentaculata[Polychaeta] at Hamble
Authors: George J. D.
Published: May 2009

A survey at Hamble Spit showed thatC. tentaculatawas less abundant near high water mark than farther down the shore. The influence of various environmental factors on the worms' distribution was investigated, and it was concluded that temperature, salinity, oxygen content, and water content were of minor importance. Both the particle size of the mud and its carbon content showed some correlation with the abundance of the worm. However, periodic strong wave action seemed to have the most influence on the distribution of the worm over the mudflat.
Notes on hydromedusae (Cnidaria) from the Adriatic Sea
Authors: Schmidt Hans-Eckart , Benović Adam
Published: May 2009

Earlier studies on the problems of the Adriatic Sea and the knowledge of its hydromedusae are restricted to the northern part. Will (1844) mentioned six species of hydromedusae found in the Bay of Trieste. Several studies ensued from the northern part of this sea, until Neppi (1912, 1915, 1922), Pell (1911, 1938), Kramp (1924), Babnik (1948) and Benović (1971a) included other areas. Some specimens from the middle and southern Adriatic are mentioned in the planktonic works of Gamulin (1948, 1976), Hure (1955, 1961), Buljan, Hure & Pucher-Petković (1973) and Vučetić (1957, 1961, 1966).
Aspects of the biology and life-history ofNemertesia antennina(L.) (Hydrozoa: Plumulariidae)
Authors: Hughes R. G.
Published: May 2009

Many workers have considered the possibility of hydroids being potentially somatically immortal, largely because of the continued production of interstitial cells which can differentiate and migrate to replace cells in other parts of the hydroid (Schmid, Schmid & Tardent, 1974). In addition, many thecate hydroids show an orderly regression and replacement of their hydranths (see review by Toth, 1969) and this led Crowell (1953) to suggest that by this means hydroids might avoid senescence. Such considerations are undoubtedly fostered by the lack of evidence for senescence of hydroids which, although sometimes showing a cycle of degeneration followed by regrowth from a dormant stolon, may live for many years in the laboratory (Strehler, 1961; Brock, 1974). Only recently has the senescent death of a hydroid (Corymorpha nutants(L.)) been recorded (Svoboda, 1973).
On the systematics and ecology of interstitial ciliates of sandy beaches in North Yorkshire
Authors: Hartwig Eike , Parker James G.
Published: May 2009

The ciliates are considered to be the dominant protozoan group in the lacunar system of marine sediments and the important role which they play in the benthic ecosystem has been emphasized (Fenchel, 1969). More than 7500 ciliate species have been described (Corliss, 1974 a) and their distribution is worldwide (Agamaliev, 1967 a; Burkovsky, 1970c; Dragesco, 1960, 1965a; Kahl, 1930–35; Petran, 1967; Raikov, 1962). However, only two surveys of the interstitial ciliates of the British Isles have been carried out (El Maghraby & Perkins, 1956; Lackey & Lackey, 1963). This paper describes a study of the systematics and ecology of interstitial ciliates of the North Yorkshire coast.
Annual fluctuations in the recruitment of Patella vulgata L.
Authors: Bowman Rosemary S. , Lewis J. R.
Published: May 2009

In an attempt to identify the causes of the natural population fluctuations on British rocky coasts, an exploratory programme on the recruitment fluctuations of certain ‘key species’ has been operating for several years. The choice of species and the emphasis upon their recruitment have been discussed elsewhere (Lewis, 1976) and were justified as the most economical means of gaining the ability to (a) ‘explain’ major changes in the general character of rocky shore communities, and (b) make predictions about natural events against which to detect regional or temporal consequences of man-made changes in water quality. Mussels, barnacles and limpets are being studied but it is the last with which most interpretative progress appears to have been made, and this paper is concerned solely with Patella vulgata L. It is, however, essentially a preliminary report in a continuing study and it illustrates the practical and interpretative problems inherent in formulating and substantiating hypotheses in this type of work.
The bioluminescence emission spectra ofPyrosoma atlanticum, P. spinosum(Tunicata),Euphausia tenera(Crustacea) andGonostomasp. (Pisces)
Authors: Swift Elijah , Biggley William H. , Napora Theodore A.
Published: May 2009

As Moseley (1879) noted, it may be imprudent to assume there must always be a ‘reason’ for observed displays of bioluminescence. However, knowledge of the colour of the light emitted may be useful for examining some of the theories about the function of marine bioluminescence. Certainly the colour of the light is important in predicting the rate of its attenuation in sea water, and the ease of perception of the light by the organism itself, or by potential predators, prey, or mates. In addition, the colour of the light may indicate something about the compounds responsible for producing the light. The present paper presents some bioluminescent emission spectra of freshly caught organisms from the Sargasso Sea.
Some observations on the gills of the oceanic sunfish,Mola mola
Authors: Adeney R. J. , Hughes G. M.
Published: May 2009

The oceanic sunfishMola molais occasionally found close to our shores, its normal habitat being the oceans throughout the world. It is replaced byMola ramsayionly in the South Pacific (Fraser-Brunner, 1951). Specimens which are caught around the British Isles normally come from the North Atlantic as a result of being washed inshore when the warm westerly winds are blowing during the summer.
The effect of copper on the eggs and larvae of plaice and herring
Authors: Blaxter J. H. S.
Published: May 2009

The importance of egg and larval mortality in the determination of year-class strength was discussed at a colloquium at La Jolla, California in 1975 (see Hunter, 1976). In addition to the obvious effects of starvation, predation and disease, pollution by such substances as copper is an important factor affecting viability. The copper concentration in sea water is generally about 1–2,µ/l. Chester & Stoner (1974), in a comprehensive survey, found an average copper concentration of 0.8µ/l in the open ocean and 0.9 µg/l nearer the shore. In British waters Prestonet al.(1974) reported a range of 1.1–1.6 µg/l and Portmann (1972a) found a range of 1–20 µg/l with the possibility of 1000 µg/l near sea-bed copper deposits.
Epizoic foraminifera on Nephrops norvegicus
Authors: Farmer A. S. D.
Published: May 2009

During studies in 1972 on the setation and development of the secondary sexual characters of the Norway lobster, Nephrops norvegicus (L., 1758), Foraminifera were observed attached to the pleopods of a mature male (carapace length 2.47 cm). On subsequent examination of the prepared material with a scanning electron microscope it was found that the Foraminifera were attached to one of the first pair of pleopods. Three individuals were observed, all of which were attached to the same pleopod on the inner surface near the tip. No further specimens of Foraminifera were encountered during detailed anatomical studies of more than 30 specimens of N. norvegicus.
Some Chemical Considerations on the Distribution of Iron in the Sea
Authors: Cooper L. H. N.
Published: May 2009

A theoretical study of the behaviour of ferric phosphate in sea water has been made with existing data. The conditions least favourable for the continued existence of ferric phosphate should occur in the upper layers of the sea during active plant growth. The formation and stability of ferric phosphate is likely to be most favoured under the more acid conditions found in the gut of many animals. Ferric phosphate is likely to be introduced into sea water in animal faeces. Experimental confirmation of this deduction is essential.

In all experimental work involving ferric phosphate in sea water, the need is indicated for very accurate control of hydroxyl-ion activity and probably pressure, and for attention to the time factor and to the physical condition of the precipitated phase. The topic is of geochemical as well as of biological interest.

Dipyridyl is a reagent for ferrous iron. Reasons are set out why in sea and lake water at high dilutions it may also determine ferric iron without presence of an added reducing agent.

Evidence is presented that ferrifluoride plays no part in the iron cycle in he sea.
A New Species of Ciliate, Trichodina Branchicola, from Some Fishes at Plymouth
Authors: Tripathi Yogendra R.
Published: May 2009

The morphology and reproduction of Trichodina branchicola n.sp. are described. Its total diameter is 30–54μ, and its height is 20–36μ,; the diameter of the striated ring is 19–33μ, and the diameter of the denticulate ring 10–20μ. There are 20–26 denticles in the ring, with 6–8 striations to each denticle. The denticles measure 1·5–2μ, in thickness, 3·5μ in length, each with a broad outer hook 2·3μ long and an inner ray 3·2μ long. The aboral cilia are fused at their base to form a complete membranelle.

This organism is found on the gills of the following marine fishes at Plymouth: Ciliata mustela, Gaidopsaurus tricirratus, Cottus bubalis, Spinachia spinachia, Blennius pholis, B. guttorugine, Trigla lucerna and Pleuronectes platessa.

The genus Vauchomia Mueller 1938 is regarded as a synonym of Trichodina.
Ecological exeriments on Foraminiferida
Authors: Murray J. W.
Published: May 2009

Fifteen experiments on the foraminiferid Elphidium crispum (L.) are described. They deal with feeding, movement, the substratum, and salinity, and their bearing on ecology.

The daily production of feeding cysts was used as a measure of the metabolic rate and healthiness of the foraminiferids. Phaeodactylum tricornutum, both living and dead, was used as food; a distinct preference was shown for living food. However, kaolin and graphite having a similar size to the Phaeodactylum were also accepted as food. It is suggested that E. crispum selects its food on the basis of size. The colour of the protoplasm is shown to be closely related to the pigments of the food

Movement in the horizontal plane is normally random. However, this species prefers a clean, hard substratum to one of clay; once a specimen has escaped from a clay substratum, it is loathe to return to it and therefore movement in this instance must be directed and not random.

Movement in the horizontal plane is normally random. However, this species prefers a clean, hard substratum to one of clay; once a specimen has escaped from a clay substratum, it is loathe to return to it and therefore movement in this instance must be directed and not random.

The rate of feeding is shown to be closely related to the salinity of the water, the feeding rate decreasing with the salinity. The amount of calcium present in sea water or in subsaline waters does not appear to affect the rate of feeding. However, lowered temperatures help E. crispum to survive for longer periods in subsaline water. At temperatures of 8° and 16° C , cultures survived subsaline water of 20%0 salinity for 38 days, but at a salinity of i5%03 only the culture kept at 8 C survived (for 15 days).
The effects of 3-amino-1,2,4-triazole on the growth of sporelings of marine red Algae
Authors: Boney A. D.
Published: May 2009

The cell production of sporelings of five species of marine red algae is inhibited by 3-amino-i,2,4-triazole (3AT).

Results show that short-term immersions in culture medium containing 3AT have a lasting effect on the growth of sporelings

This growth inhibitory effect is reversed by addition of adenine.

Protracted contact with 3AT results in some chlorosis of the sporeling

The growth inhibitory effects of 3AT are more marked with sporelings of intertidal red algae than with sublittoral species.
Observations on the biology of pandalus montagui [Crustacea: Decapoda]
Authors: Allen J. A.
Published: May 2009

An account is given of the populations of P. montagui occurring off the Northumberland coast at depths ranging from 20 to 50 fm. Sampling, which extended from 1954 to 1961, shows that the population in 20–30 fm is composed predominantly of o-group males and females and smaller numbers of 1-group females while that in 50 fm is composed predominantly of 1 and 2 group males and females. This difference can be explained in terms of sex change and migration.

Eggs laid in the period from the last week in November to the first week in January hatch by the end of April. Growth of the new year-group is so rapid that they mature in time for the next breeding season. Egg numbers vary from 200 to 3000.

It can be calculated that the number of larvae hatched out inshore exceeds that offshore by 15 times, but many of the larvae produced by the deep-water.
The biology of Calocaris macandreae [Crustacea: Thalassinidea]
Authors: Buchanan John B.
Published: May 2009

Previous work on the biology and distribution of Calocaris is discussed briefly. The distribution in Northumberland waters is considered in relation to depth and bottom sediment.

Quantitative monthly samples show that population numbers remain very stable throughout the year. A well marked egg-laying period occurs in January-February when relatively few eggs (average 38) are attached to the pleopods. Eggs are carried for 8–9 months and hatch in September-October. By a combination of size-frequency distribution and gonad-developmnt classification the age-groups in the population are interpreted. After passing through a phase of testes development and spermatophore formation individuals lay their first batch of eggs at the end of the 5th year. The ovaries regenerate over a 2-year period and a second egg-laying takes place at the end of the 7th year with a possible third at the end of the 9th year.

The incidence of soft individuals in the samples together with observed changes in the coverage with epifaunistic growths indicate that after entering the 5th year a single annual moult cycle begins with a slowing down in growth rate.

Population numbers, fecundity and larval survival are discussed. Both the survival curve and the apparent lack of serious predation suggest that the population reaches senescence
Observations on the food value of seven species of Algae to the larvae of Ostrea Edulis I. Feeding experiments
Authors: Walne P. R.
Published: May 2009

Six species of algae, Chlorella marina Butcher, Dunaliella tertiolecta Butcher, Isochrysis galbana Parke, Monochrysis lutheri Droop, Phaeodactylum tricornutum Bohlin and Hemiselmis virescens Droop were fed to oyster larvae in bacteria-free culture. In addition, cultures of Chlorella stigmatophora Butcher, Isochrysis galbana and Phaeodactylum tricornutum containing bacteria were also used. Cultures of galbana containing bacteria were used as controls in all series of experiments. In each series various densities of food, expressed both as cell numbers and as packed cell volume, were fed to the larvae of Ostrea edulis L. for 22–46 h and the change in the mean size of the larval population was used as the index of the value of the food.

The experiments with Chlorella confirmed previous work that organisms of this genus have little value as food for larvae. With Dunaliella and Phaeodactylum growth was better at low food densities with some (but not all) batches of larvae compared with Isochrysis. The comparison of cultures of Isochrysis and Phaeodactylum with and without bacteria showed no consistent improved growth with either food. Monochrysis had about the same food value as Isochrysis. With Hemiselmis some growth was obtained but not as much as with Isochrysis.
The loss of mercury from stored sea-water solutions of mercuric chloride
Authors: Corner E. D. S. , Rigler F. H.
Published: May 2009

The disappearance of mercury from stored sea-water solutions of mercuric chloride has been studied by means of the chloroform-dithizone procedure and by the use of radioactive mercury (203Hg).

When sea water is enriched with nutrients facilitating the growth of bacteria, the rate at which mercury is lost from the solution is markedly increased. On the other hand, when the sea water is treated in various ways which prevent the development of bacteria, the loss of mercury from solution is considerably reduced.

Rates of loss of mercury measured by the chloroform-dithizone procedure and by the use of tracer isotopes are in good agreement only in the early stages of the experiments. Thus, at a time when approximately hah0 the mercury has been lost, titrations with chloroform-dithizone only account for about 50% of the mercury determined by measurements of radioactivity. Further findings have suggested that this discrepancy arises from the fact that a considerable amount of the mercury is taken up by bacteria and converted into a form which is not detectable with chloroform-dithizone.
Sea currents off the Northumberland coast
Authors: Evans Frank
Published: May 2009

Observations have been made of the surface currents off the Northumberland coast over a period of 12 months, using a free-floating buoy. A mean vector current was found, setting 114° at o·i knot. Currents flowed into the quadrant to the right of downwind except when this would have directed them ashore. A relationship is established between wind speed and current speed.