bluuebunny/crossref_metadata_2025_split huggingface dataset:
The distribution of Polychaeta in offshore deposits in the Irish Sea
Authors: Southward Eve C. 
Published: May 2009

During 1952–54 a survey was made of the Polychaeta living in the offshore bottom deposits of the south of the Isle of Man. These deposits range from stones and coarse gravel to soft mud; samples were obtained with a van Veen grab sampler and various dredges.It was found that, although some species were widely distributed, each bottom deposit had a typical fauna, and that where the deposits graded into one another the polychaete fauna was also mixed. The distribution of each species appears to depend mainly on its mode of life and feeding habits; some can exist in several types of deposit or habitat, while others are very much restricted in their distribution.The Polychaeta formed a high proportion, numerically, of the macrofauna, exceeding any other animal group, except possibly in the coarse gravels. However, the density of the polychaete population was low compared with other areas of the British Isles, and this may be correlated with the comparatively low biomass in the area.
Observations on the resistance of Tigriopus fulvus (Fischer) to changes in temperature and salinity
Authors: Ranade M. R. 
Published: May 2009

Tigriopus fulvus can live normally within a salinity range of from 4·2 to 90%.In waters of salinities above 90% it falls into a state of apparent death from which it can recover if transferred back to lower salinities.The relation between immersion period and the recovery period is only slightly different at different salinities.The lethal temperatures vary between 32·0 and 41·8°C depending on the salinity of the sea water, the lethal temperature being higher in higher salinities.The fluctuations in salinity and temperature in the pools where the animals were collected are well within their tolerance limits.T. fulvus is well adapted to its habitat.
Seasonal variations in host-parasite relations between fish and their Protozoa
Authors: Noble Elmer R. 
Published: May 2009

From July 1955 to June 1956 a study of host-parasite relations between three species of marine fish and their Protozoa was made at Plymouth.Callionymuslyra, a bottom-dweller, tends to be more abundant during the summer months, consumes a wide variety of food, and was more heavily infected with Protozoa than were the other two species offish.Gadus merlangusis an active predator, feeding on small fish, and although it has about the same numbers of kinds of Protozoa as doesC. lyra, it was less heavily parasitized.G. merlangus, however, was more heavily parasitized with worms than were the other two fish.Microstomus kittis a sluggish bottom-dweller, feeding on annelids, and, although over 99% were infected with myxosporidia, the intensity of infection was generally low. Very few other parasites were found inM. kitt.An active predatory habit combined with a taste for a wide variety of food appears to predispose to heavy parasitism. Some evidence for seasonal variations in intensities of protozoan infection inCallionymus lyrawas obtained, but for conclusive results more precise methods of measuring numbers of parasites, and further studies carried on over a period of at least three consecutive years, must be made. The report is presented primarily to emphasize the importance of an ecological approach to the study of parasitology.
The toxin fromGymnodinium veneficumBallantine
Authors: Abbott B. C. , Ballantine Dorothy 
Published: May 2009

Methods of extraction of the toxin from cultures ofGymnodinium veneficumare described. This is now done by dialysis and evaporation under reduced pressure. The toxin molecule must be large, as it cannot penetrate a dialysis membrane; it is soluble in water and the lower alcohols, but insoluble in ether and chloroform. It is unstable in acids, turning into another toxic product, and is decomposed by hot alkali, though in neutral solution is more or less thermostable. The toxin as it occurs in sea water is not the same as paralytic shellfish poison, but there are some resemblances between this and the 'acid extract', though much more work is needed to check this point.The action of the toxin on a variety of animals is described, and an attempt is made to devise an approximate assay technique using gobies as the test animals.The action has also been observed on a range of isolated preparations, and although the final conclusion as to the mode of action is not quite clear, we feel confident that the site of action in whole animals is in the nervous system, probably acting on ganglion transmission. With regard to the mode of action it depolarizes nerve and muscle membranes. It also abolishes the potential across frog skin without measurably altering the skin resistance.This depolarization probably occurs by interference with the sodium exchange mechanism, allowing rapid entry of sodium into the cells.
The distribution of the coralCaryophyllia smithiiS. & B. on the Scottish continental shelf
Authors: Wilson John B. 
Published: May 2009

The published records of the occurrence of the Devonshire Cup CoralCaryophyllia smithiiStokes and Broderip in Scottish waters are widely scattered throughout the literature. Rees (1962, 1966) listed several of these and suggested that the paucity of records was a reflexion of the comparatively little systematic collecting that had been done on the Scottish coasts and on the continental shelf.The purpose of the present paper is to collate and review the published records of the distribution ofC. smithiiand to present new data derived from extensive investigations carried out by the Institute of Oceanographic Sciences, Wormley, as part of a study of shelly faunas and sediments on the continental shelf west and north of Scotland. Additional records obtained from several other sources are also included.
Feeding and gut structure of Parathemisto gaudichaudi (Guerin) (Amphipoda, Hyperiidea)
Authors: Sheader M. , Evans F. 
Published: May 2009

Previous (workers who have examined the gut contents of members of the genus Parathemisto, and who have kept and fed specimens in laboratory conditions, have concluded that they are chiefly carnivorous in habit, feeding largely on zooplankton, and to a lesser extent on phytoplankton (Conover, 1960; Baker, 1963; Kane, 1967).The gut of P. gaudichaudi has been found to contain almost intact copepods, especially Calanus and occasionally Temora (Bigelow, 1926 – Gulf of Maine); young specimens of Euphausia superba (Hardy & Gunther, 1935 – Antarctic); and copepods (Nemoto & Yoo, 1970). Siegfried (1965 – west coast of S. Africa) found P. gaudichaudi to be a rather indiscriminate feeder, its gut contents reflecting the composition of the plankton.
On the biology ofCalanus finmarchicus: XIII. Seasonal change in weight, calorific value and organic matter
Authors: Comita G. W. , Marshall S. M. , Orr A. P. 
Published: May 2009

The length, weight, calorific value and organic matter content ofCalanus finmarchicus, Stage V, males and females, were measured in monthly samples taken from April 1962 to June 1963.There is considerable variation throughout the year and all stages had their maxima of weight and calorific value in spring, 1962, and winter 1962–63.The calorific value and weight are closely correlated so that, knowing the dry weight, the calorific value can be calculated from it. The correlation is closest in Stage V and, for these, only the dry weight need be known. Since the relation-ship is slightly different for males and females the sex of the adult must be known as well as the dry weight; curves showing these relationships are given.The calorific value obtained from organic-matter analysis at times deviates widely from the values obtained in direct bomb calorimetry, and it is concluded that in the method used not all the fat is accounted for.In weight, calorific value, and organic matter, but not in length, Stage V for a good part of the year show higher figures than adults.In comparing the weights with those of other years and other places, the annual pattern is found to vary considerably. The spring maximum seems to occur every year, but there may be either a maximum or a minimum in autumn and winter.
A new species of Lumbricillus, with a revised check-list of the British Enchytraeidae [Oligochaeta]
Authors: Tynen Michael J. 
Published: May 2009

A new species of enchytraeid worm, Lumbricillus christenseni, is described and compared with some closely related members of the genus Lumbricillus.Twelve other species of enchytraeid, recorded in the British Isles for the first time, are listed.The habitats and localities in which these new records have been found in North Wales and Europe are also listed.A revised check-list of the British Enchytraeidae is given.Following the publication (Nielsen & Christensen, 1959) of a critical revision of the taxonomy of European enchytraeids, which resolved much of the confusion in the existing literature, the task of identifying the members of this family has been made much easier. Between 1961 and 1964, during an investigation of the littoral Enchytraeidae of the coasts of Anglesey and the Menai Straits, twelve species of enchytraeid new to the British Isles and one species new to science were identified. The new species, a member of the genus Lumbricillus Ørsted 1844, is hereby named Lumbricillus christenseni, after Dr Bent Christensen of the University Zoological Museum, Copenhagen, in recognition of his contribution to our knowledge of enchytraeid taxonomy.Lumbricillus christenseni sp.nov.Location and habitatThis worm has been found in only one location, namely, Porth Eilian, a small bay at the north-east corner of the island of Anglesey, North Wales. The worm was most common at about high-water mark of the neap tide, in a mixture of sand and pebbles with a sparse covering of undecayed weed. The specimens examined were all taken within 5 cm of the surface. There was a large proportion of mature specimens at the time of collection, that is, late spring and early summer of 1964.
The biology ofEchinocardium cordatum[Echinodermata: Spatangoidea] from different habitats
Authors: Buchanan John B. 
Published: May 2009

An offshore and a littoral population ofEchinocardium cordatumhave been observed for a period of 7 years, starting from the time of their simultaneous larval settlement and establishment.The littoral population was found in clean sand of low organic content. Individuals burrowed to a depth of 15 cm and could move through the sand at a speed of 6–8 cm/h. The test length increased at an average increment of 8 mm/annum. Breeding first took place in the third year and continued each year after.The offshore population was found in very silty sand at depths of 30–40 m. Here individuals burrowed to a very shallow depth, 2 cm. or less, and moved very slowly through the sediment. The annual increment of test growth was only about 3 mm. Estimations showed that the littoral population had a production rate four times greater than the offshore. The offshore population did not reach sexual maturity during the period of observation. No new settlement was observed anywhere in the area during the period of observation.The offshore population occurred in large discrete patches, each displaying a quantitatively concentric pattern with a central area of high density. Samples taken at single stations within the patch showed that the distribution was random for most of the year but that aggregations formed in June, July and August.Both populations showed a steady mortality rate of about 15 % per annum and the longevity was estimated to be in the region of 15 years.Based on prolonged aquarium observations of the feeding behaviour, reasons are given for believing that the surface collecting activities of the penicillate tube-feet of the anterior ambulacrum should be considered as a true feeding mechanism.
A Comparative study of Reproductive Cycles in Four polychaete Species belonging to the Family Cirratulidae
Authors: Gibbs P. E. 
Published: May 2009

Gametogenesis has been studied in four cirratulid polychaetes: Caulleriella caput-esocis, Tharyx marioni, Cirriformia tentaculata and Cirratulus cirratus.In all four species, sperm development follows a similar course of events, with the sperm cells being grouped in spheres and then platelets before developing tails to give rosettes which finally disintegrate to release the active spermatozoa. Except in Cirratulus, there is a well-defined annual cycle in the development of sperm.Oogenesis in Caulleriella and Cirriformia is similar in that the growth curve of the oocytes is roughly sigmoid. In Tharyx the release of the oocytes to the coelom is delayed and discrete ovaries are formed, only the later stages of oocyte growth taking place within the coelom. In contrast to the above three species, oogenesis in Cirratulus does not show an annual cycle.Maturation of the oocytes within the coelom prior to shedding has been established in Tharyx, Cirratulus and Cirriformia. In the former two species meiosis proceeds as far as the metaphase I stage and in the latter to the anaphase I stage, before the oocytes are released. Fertilizations were achieved only with oocytes which had matured in all three species. In the fourth species, Caulleriella, no fertile oocytes were discovered.The diameters of the mature oocytes and the main spawning seasons of the four species at Plymouth are as follows: Caulleriella, about 110 μ (August to October); Tharyx, 200– 220 μ (late October to early November); Cirriformia, about 117 μ (late June to early July); Cirratulus, 135–150 μ (throughout the year).
Structure and Abundance of Receptors of the Unspecialized External Epithelium ofNassarius Reticulatus[Gastropoda, Prosobranchia]
Authors: Crisp Mary 
Published: May 2009

The epithelial receptors ofNassariusare primary sense cells. The sensory endings are abundant on the tentacle tips, anterior border of the foot and ventral external surface of the siphon tip. Densities are a small multiple of 1032 endings/mm2.Type 1 ciliated endings are of ubiquitous occurrence. The ultrastructure of type 1 endings is uniform, though the static and motile bundles of sensory cilia may be distinguished by the random or uniform orientation of the ciliary subfibrils and basal feet. Ciliated receptors probably include both chemo- and mechanoreceptors.A distinct ultrastructural type of sensory ending (type 2), confined to the siphon tip, consists of a small pit in the peripheral dendrite close to the epithelialsurface. The pit contains whorled microvilli and a few cilia. It may be photoreceptive.A small amount of convergence of sensory information may occur in peripheral nerve.
Aspects of the Circulatory Physiology and Muscle Systems of Deep-Sea Fish
Authors: Blaxter J. H. S. , Wardle C. S. , Roberts B. L. 
Published: May 2009

Mesopeiagic fish without swim bladders, found in depths from 100 to 1000 m, have soft bodies with a very high water content (88–95%) low haematocrits (5–9%), smallhearts, a low proportion of red muscle, and large lymph ducts. Species possessing swim bladders have a lower water content (70–83%), higher haematocrits (14–35%), larger hearts, more prevalentred muscle and smaller lymph ducts. Some active surface species have still less water (64–74%) and higher haematocrits (48–57%).The soft watery fish appear to use skeletal reduction and high water content asa buoyancy mechanism but there is no evidence, judging from analyses of freezing-point depression of the plasma and muscle fluid, that they maintain an extra low ionic content to assist buoyancy. Although oxygen is probably adequate in the deep water, there may be some constraint on activity because the oxygen-carrying capacity ofthe blood is low and oxygen may be limited at the tissues. This is partly compensated for by the high proportion of anaerobic white muscle and the large lymph system. These watery fish appear to be best adapted to short bursts of activity. Nevertheless they do make diel vertical migrations which may cause them to reach the limits of their aerobic metabolic systems.The mesopeiagic species with swim bladders are much more similar in their circulatory characteristics to inshore fish. They also make quite substantial vertical migrations with the concomitant problem of adjusting buoyancy by varying the pressure within the swim bladder. Metabolically this is unlikely to be unduly difficult.
Gonadotropic Mitogenic Activity of the Optic Gland of the Cuttlefish,Sepia Officinalis, During Sexual Maturation
Authors: Koueta N. , Camou-Boucaud E. , Renou A.M. 
Published: May 2009

A cytological study was carried out on the main cells of the optic gland of male and femaleSepia officinalisL. during sexual maturation (animals collected in the field). The results were correlated with experimental data on the mitogenic action of optic gland extracts collected during a period of secretory activity.The main cells of the optic gland show some of the features of protein-secreting cells, although they are not very pronounced. The secretory activity of the cell was found to be correlated with a peak of mitogenic activity occurring in September/October in the case of the males and in November in that of the females. The secretion of gonadotropic mitogenic factor varies throughout the sexual cycle ofSepia officinalis. This activity is correlated with a rapid multiplication of spermatocytes and spermatogonia in the males, whereas in the females it corresponds to previtellogenesis.
A Preliminary Survey of the Benthic Macrofauna and Sediments in Lochs Etive and Creran, Sea-Lochs Along the West Coast of Scotland
Authors: Gage John 
Published: May 2009

The hydrographic conditions in the two sea-lochs is briefly described where relevant to the survey of the benthos. Seasonal changes in temperature and salinity in Loch Etive appear to follow roughly the local coastal pattern but usually with a lag in timing that is considered to be because of the restricting effect of the twin sills. Replenishment of deep-basin water by ventilation over the sills is spasmodic and controlled by surface stratification; the latter being due primarily to freshwater runoff. This situation contrasts with Loch Creran which has only a small catchment and where the seasonal hydrography closely follows the pattern outside. Other possible reasons for the differences observed between the two lochs are discussed.The bottom fauna of both lochs was sampled semi-quantitatively with an anchor dredge at 22 stations in Loch Etive and 8 in Loch Creran at depths from 7–117 m. A detailed list of the fully marine fauna present is given. The species occurrences in the single-haul samples are compared objectively using a coefficient of similarity of the presence/absence records. An attempt is made to relate the groupings shown up to the classical ‘bottom community’ concept, to the feeding-type categories of the bottom animals and to analysis of particle size of sediment samples taken at the same stations. A correlation to sediment type was apparent. This is considered to owe as much to local hydrographic conditions which the sediment reflect as to the sediment itself.
Function of Theswimbladder-Inner Ear-Lateral Line System of Herring in the Young Stages
Authors: Blaxter J. H. S. , Denton E. J. 
Published: May 2009

INTRODUCTIONThe preceding paper (Allen, Blaxter & Denton, 1976) describes the development of the swimbladder-inner ear-lateral line system of the herring.In the larval stage of herring the pro-otic bullae start to develop at a body length of about 18 mm. Between 18 and 30 mm the bullae become filled with gas. At 26 mm the lateral recess membrane starts to develop, becoming silvered at about 42 mm. The lateral line develops between 19 and 45 mm. The swimbladder silvers and contains gas from about 38 mm. The adult system is complete at 50–60 mm body length, some four months after hatching.This paper concerns the system in its intermediate stages of development. It examines the problems of how the bullae are filled with gas and how the gas spaces are maintained. It gives evidence on the possible roles of the gas-filled spaces as hydrostatic pressure receptors and as aids to buoyancy and discusses the limitations of the system before it can gain or lose gas to a gas-filled swimbladder.
Studies on The Biology of The Entocommensal RhynchocoelanMalacobdella Grossa
Authors: Gibson Ray 
Published: May 2009

IntroductionDespite the amount of literature published concerning the entocommensal rhynchocoelan,Malacobdella grossa(O. F. Müller), few references have been made about its ecology and life-history, and these for the most part consist of little more than isolated observations. The ecological knowledge available is composed almost exclusively of details pertaining to geographic distribution, hosts from which the worm has been recorded, and reports of the infection incidences found. Apart from suggestions by von Kennel (1878) and Gering (1911) that a relationship exists between host size and both worm incidence and size, the only detailed analysis of the host-commensal associations is that of Gibson (1967), who established a statistical correlation between host size and both incidence of infection and nemertean length, recorded the disposition frequency of the worm within its host, and examined both the occurrence of multiple infections and theMalacobdellapopulation size composition.Von Kennel (1878) further suggested that host-commensal size relationships would depand on the age (i.e. size) at which infection by the pelagic larvae occurred, and Ropes (1963) speculated on the role played by surface currents upon larval distribution.
Studies on the Growth of Phaeodactylum Tricornutum IV. Comparison of Different Isolates
Authors: Hayward J. 
Published: May 2009

IntroductionThe diatom Phaeodactylum tricornutum Bohlin has been used in numerous experiments on the physiology and biochemistry of diatoms since the publication of the first paper involving this organism by Allen & Nelson (1910). The taxonomic position of the organism has been dealt with by Lewin (1958), who also lists the papers which she considers to have involved the use of P. tricornutum. The present study reports the results obtained from a comparison of different isolates of this organism.
Vitamin B12and Marine Ecology. IV. The Kinetics of Uptake, Growth and Inhibition inMonochrysis Lutheri
Authors: Droop M. R. 
Published: May 2009

57Co-labelled vitamin B12was used to study the kinetics of vitamin B12limitation inMonochrysis lutheriin continuous and exponentially growing batch cultures and in washed cell suspensions.Specific growth rate in the chemostats was found not to depend directly on medium substrate concentration but on the concentration within the cells (cell quota), obeying a hyperbolic equation of the form
Some Observations on the Biology and the Ecology of a Venus Striatula Population in the Bay of Douarnenez, Brittany
Authors: Guillou J. , Sauriau P. G. 
Published: May 2009

INTRODUCTIONVenus striatula (da Costa) (= Venus gallina L.) occurs in high densities in shallow water on a bottom of clean fine sand in the Bay of Douarnenez. The environmental conditions are characterized by an obvious sediment instability due to a high exposure to westerly swells (Guillou & Le Moal, 1978). This species is preferentially distributed in the fine sands (Petersen, 1913; Thorson, 1957), but is relatively tolerant towards certain ecological factors and so is sometimes found in very muddy sediments. It also shows an extended latitudinal range, since it is recorded from the Lofoten Islands to the Canaries, in the Mediterranean and the Black Sea (Tebble, 1966).