bluuebunny/crossref_metadata_2025_split huggingface dataset:
Exogenous Otoliths of Elasmobranchs
Authors: Fänge R. 
Published: May 2009

In cartilaginous fish, holocephalians and elasmobranchs, the endolymphatic system of the inner ear generally communicates with the exterior via the endolymphatic ducts. The openings of the ducts on the dorsal side of the head were known already by eighteenth-century anatomists (Retzius, 1881). In certain elasmobranchs mineral particles from the environment pass into the inner ear through the ducts. Stewart (1906) described presence of sand grains in the membranous labyrinth of the shark,Squatina.Nishio (1926) found black volcanic particles of varying sizes in the endolymphatic duct, the sacculus and the lagena ofSquatina angelusand the ray,Torpedo ocellata, from the gulf of Naples.I have studied the inner ear of two species of electric rays,Torpedo nobilianaandT. marmorata.Considerable amounts of fine sand grains are found in the endolymphatic system of both species. The mineral particles are kept together by a gelatinous material or occur free in the endolymph. The size of the sand particles varies between 10 and 400μm. The grains are white or transparent, yellow, brownish or black. Mineralogical analysis with a polarizing microscope reveals that 85–90% of the particles consist of quartz, 5–10% of calcium carbonate and less than 5% of an unidentified opaque mineral, possibly corroded felspar. The grains are irregular with rounded or sharp edges. They differ in appearance from the round or lens-shaped concentrically layered aragonite octoconia found in the labyrinth of most elasmobranchs (Retzius, 1881; Nishio, 1926). The present findings seem to be consistent with the results by Stewart (1906) and Nishio (1926) suggesting that certain psammophilous elasmobranchs lack the ability to produce calcium carbonate otoliths and compensate for this by uptake of sand grains through their endolymphatic ducts.
Burrowing behaviour and anaerobiosis in the bivalveArctica islandica(L.)
Authors: Taylor A. C. 
Published: May 2009

In laboratory tanks as well as in the seaArctica islandicashows a pattern of intermittent burrowing activity. Periods spent at the surface of the deposit alternate with periods buried several centimetres beneath the surface of the sand, during which the animals respire anaerobically. There is no obvious rhythmicity to this behaviour; the duration of periods spent beneath the surface is very variable even in the same animal, but normally lasts between 1 and 7 days.On the return to aerobic conditions both the heart rate and oxygen consumption areincreased but decline gradually during the following 20–25 h. This increased oxygen uptake is caused primarily by an increase in oxygen utilization but there is little change in ventilation rate. Both the initial rate of oxygen consumption and the duration of the recovery period show a correlation with the duration of the period of anaerobiosis. The concentration of alaninc in the blood ofArcticais high immediately after the return to aerobic conditions but declines during the recovery period. The similarity in the time taken for the concentration of alanine in the blood and the oxygen consumption ofArcticato return to normal levels suggests that at least part of this increased oxygen demand is associated with the metabolism of end-products of anaerobiosis.
The life-cycle of Sagitta elegans Verrill And Sagitta setosa J. Müller in Galway Bay, west coast of Ireland, 1972–1973
Authors: O'Brien F. I. 
Published: May 2009

An oceanographic survey of Galway Bay was initiated in 1972. Plankton samples were collected on monthly cruises at selected areas in the bay.Sagitta elegans and Sagitta setosa were found not to be entirely resident in the bay and recruitment of all stages occurred from outside the bay several times during the study. It has also been suggested that the younger stages, especially of S. elegans, were washed out of the bay in the upper layers.S. elegans was breeding in Galway Bay in July, August and September 1972 and possibly April and May 1973. Breeding was observed in the S. setosa population in September 1972 and from August to November 1973.
The biology Of Laminaria hyperborea IX. Growth pattern of fronds
Authors: Kain Joanna M. , Jones N.S. 
Published: May 2009

INTRODUCTIONIn the genus Laminaria the origin of the growth of the frond (blade, lamina) is known to be the meristematic transition zone between frond and stipe. Parke (1948) showed, by observing holes punched in the frond, that the fastest rate of growth in length in L. saccharina (L.) Lamour. was in the proximal 25 mm. However, during measurements of the rate of growth of fronds of plants of known age on previously cleared areas (Kain, 1976), it was noted that in L. hyperborea (Gunn.) Fosl. the maximum rate of elongation occurred at some distance from the transition zone. This led to an investigation of the whole pattern of growth, in terms of elongation, increase in area, decrease in thickness and change in cell size and numbers over the surface of the frond at different stages.
The nitrogen concentration requirement of D-glucosamine for supporting effective growth of marine microalgae
Authors: Berland B. R. , Bonin D. J. , Maestrini S. Y. , Lizárraga-Partida M. L. , Antia N. J. 
Published: May 2009

INTRODUCTIONA comparative survey on the capacity of several nitrogenous compounds to support marine phytoplankton growth showed urea as the best and D-glucosamine as the poorest supplier of organic-nitrogen at a concentration of 500 /g-at. N per litre (Antiaet al., 1975a). The quality and degree of growth on glucosamine was always so inferior that the evidence appeared insufficient to establish whether this compound was actually being metabolized by the algae. By analogy with the substrate-utilization kinetics reported for growth of other micro-organisms such as yeast (e.g. Tseng & Wayman, 1975), the probability was considered that the glucosamine concentration used in the above survey may have been too low for adequate uptake under the test conditions chosen and that elevated concentrations, in facilitating such uptake, may provide unequivocal evidence of algal capacity for metabolism and utilization of this substrate. However, such concentration elevation would require to be below levels that may become inhibitory to growth, and these inhibitory levels may themselves vary from one species to another. Antia & Chorney (1968) reported 5 mM glucosamine to be toxic to growth of the cryptomonadHemiselmis virescens, whereas McLachlan & Craigie (1966) observed growth of the diatomsCyclotella crypticaandThalassiosira fluviatilison five times this level of concentration.
Cephalopod remains from sperm whales caught off Iceland
Authors: Clarke M. R. , Macleod N. 
Published: May 2009

INTRODUCTIONThis analysis of cephalopod remains, particularly the mandibles or beaks, from sperm whales caught off Iceland is one of a series made by the authors on remains from various geographical regions including Madeira (Clarke, 1962a), Spain (Clarke & MacLeod, 1974), Western South America (Clarke, MacLeod & Paliza, 1976, South Africa, Western Australia, the Antarctic and the South Atlantic (Clarke, 1976, 1977). Other workers have described similar collections from New Zealand (Gaskell & Cawthorne, 1967; see also Clarke, 1976, 1977) and the North Pacific (Akimushkin, 1954; Betesheva & Akimushkin, 1955; Tarasevich, 1963). The present analysis has depended upon a development in the technique of identification of cephalopod lower beaks from an early search for criteria (Clarke, 19626) to a point where many species can be identified from lower beaks (Mangold & Fioroni, 1966; Iversen & Pinkas, 1971; Clarke, 1977).
Skin impulses and locomotion in an ascidian tadpole
Authors: Mackie G. O. , Bone Q. 
Published: May 2009

INTRODUCTIONAscidian tadpoles are short-lived, actively swimming larvae. On attachment to their preferred substrates they absorb the tail, and with it all their locomotory equipment. The behaviour is in general geared to the short-term problems of dispersion and settlement (Crisp & Ghobashy, 1971).The small size of these tadpoles (2 mm inDendrodoa grossularia, van Beneden, the species used) makes them difficult to handle. Surgical operations on the nervous system (Kasas, 1940), such as we were able to perform on the tadpole-like but largerOikopleura(Bone & Mackie, 1975) are scarcely feasible here. Nevertheless, it is desirable to know more about the tadpoles’ locomotory organization if only because their possession of the chordate type of locomotory equipment raises interesting questions concerning possible functional parallels and evolutionary origins.
Reduction of the intestinal parasite fauna of marine fishes in captivity
Authors: Möller H. 
Published: May 2009

INTRODUCTIONSeveral authors (Cable &amp; Hunninen, 1942; Dogiel, Petrushevski &amp; Polyanski, 1958) noted that fishes while being kept in aquaria, lose the intestinal parasites with which they had become infested in nature. Up to now no quantitative examinations have been made on this subject. A better knowledge of the behaviour of parasites of fish in captivity seems to be of interest for several reasons.The possible elimination of intestinal parasites by quarantining the host fish would be of importance in case of parasites which are able to complete their life-cycle in the aquarium and which might provoke mass-infection.
The mechanical relationships between the clupeid swimbladder, inner ear and lateral line
Authors: Denton E. J. , Blaxter J. H. S. 
Published: May 2009

INTRODUCTIONIn earlier papers (Allen, Blaxter & Denton, 1976; Blaxter & Denton, 1976) an account was given of the development and structure of the swimbladder-bulla-lateral line system of the herring Clupea harengus L. and sprat Clupea sprattus (L.) and its function in the larval stage. In this paper we describe experiments on juveniles of these species in which the system is fully developed.
The Ultrastructure of the Meristoderm Cells of the Hapteron ofLaminaria
Authors: Davies J. M. , Ferrier N. C. , Johnston C. S. 
Published: May 2009

This investigation of the ultrastructure of the cells of laminarian haptera is part of a more detailed study of the growth of marine macroalgae and their inter-action with the environment. A major section of the programme is an attempt to establish the relationships between physiological, biochemical and structural (including ultrastructural) changes which occur during cell growth in brown algae and to compare such observations with those recorded for higher plant cells.The choice of haptera (PI. IA) for much of this work on brown algal cell growth is based on their suitability for the interpretation of enzymological data on a cellular basis. Hapteron growth shows several convenient similarities to that in primary meristems of higher plants. Although lamina growth is from an intercalary meristem at the base of the lamina (transition zone), hapteron growth is essentially apical (Reinke, 1876), and differentiating cells are arranged in rows leading backwards from the apex (PI. IB, c). Thus, progressive sections cut from the tip backwards will contain an increasing percentage of vacuolate, elongating cells, as in the flowering plant root.
Biochemical Changes in Fed and Starved Oysters, Ostrea Edulis L. During Larval Development, Metamorphosis and Early Spat Growth
Authors: Holland D. L. , Spencer B. E. 
Published: May 2009

Although a great deal is known about methods for the culture of commercially important bivalve larvae (see, for example, Loosanoff & Davis, 1963; Walne, 1964, 1966) little information is available on the biochemical changes that take place during larval development.Collyer (1957) determined the glycogen content of several batches of newly released larvae of Ostrea edulis and found that viability was not related to the initial glycogen content. Millar & Scott (1967) showed that lipid was the major energy reserve used during starvation by newly released O. edulis larvae. Recently Helm, Holland & Stevenson (1973) have shown that the initial growth rate of newly released O. edulis can be positively correlated with the lipid content of the larvae on liberation.The present paper describes the biochemical changes that occur during larval development, metamorphosis and early spat growth of O. edulis. In addition, short-term starvation experiments were carried out to determine whether protein, lipid or carbohydrate serves as the main energy reserve during each phase of development.
Qualitative Studies on the Metabolism of Naphthalene in Maia Squinado (Herbst)
Authors: Corner E. D. S. , Kilvington C. C. , O'Hara S. C. M. 
Published: May 2009

Many studies have been made on the metabolism of polycyclic aromatic hydrocarbons in mammals and it has been shown that these animals can convert compounds such as naphthalene into several metabolites (see, for example, Corner & Young, 1955). Baldwin (1957) has remarked on the ability of mammals to metabolize substances that they are unlikely to meet ‘except through the medium of the laboratory’. Marine animals, how-ever, can encounter these compounds in their normal environment, considerable quantities of polycyclic aromatic hydrocarbons being present in crude oil (Boylan & Tripp, 1971), in which form substantial amounts must be released into the sea annually.Little work has been done on the metabolism of naphthalene in marine animals, apart from studies confined – as far as we are aware – to experiments with three species of fish (Lee, Sauerheber & Dobbs, 1972) and the mussel Mytilus edulis L. (Lee, Sauerheber & Benson, 1972). Data obtained using fish were consistent with those of earlier studies with mammals in showing that the hydrocarbon is converted into hydroxylated derivatives: but no evidence of naphthalene metabolism was found in the experiments with Mytilus. Indeed, until the present work, the only species of invertebrate that has been found to metabolize the compound is the housefly Musca domestica L. (Terriere, Boose & Roubal, 1961).The present study, using Maia squinado (Herbst), has been carried out as part of a general investigation of the accumulation of polycyclic aromatic hydrocarbons in marine food chains and was designed to establish whether a marine crustacean possesses a means of metabolizing naphthalene by converting it into soluble excretion products.
The Structure and Innervation of the Locomotor Muscles of Salps (Tunicata: Thaliacea)
Authors: Bone Q. , Ryan K. P. 
Published: May 2009

Salps swim by rhythmic contraction of the hoop-like bands of muscle which form a series of incomplete annuli along the body. The histology of these muscle bands was briefly examined by various early workers, such as Dolley (1887) and Knoll (1895), but was little known until Fedele (1932,1938) published the results of his careful investigations of a variety of species. His observations demonstrated the complexity and peculiarity of the muscle fibres forming the bands, which, as he pointed out, are in some respects comparable to those of arthropods in the arrangement of the sarcomeres. In all the species he examined, Fedele found that the muscle fibres were essentially similar in organization: a central granular core containing large nuclei was surrounded on the free borders of the fibre by a layer of myofibrils. However, this general arrangement differed in detail between different species, and Fedele recognized five types of muscle fibre, distinguishing these types upon such criteria as the fibrillar arrangement, and the disposition of the nuclei. In an earlier paper (Fedele, 1925) he had also given very clear figures of the manner in which these muscle fibres were innervated. He found that dis-crete motor end-formations occurred on the surface of the muscle bands, and that these were frequently intercalary, unlike the motor terminations of vertebrates.Fedele's work was based upon very careful observation of living and fixed material at the light microscope level; in the present note, we extend his observations by describing the ultrastructure of these curious protochordate muscle fibres.
The Occurrence of a Second Species of Lophius in Northern European Waters
Authors: Wheeler Alwyne , De Groot S. J. , Nijssen H. 
Published: May 2009

A second species of angler-fish, Lophius budegassa Spinola, 1807, is reported from British waters. This species has hitherto been reported only as far north as the Bay of Biscay. This is not thought to be an active extension of the range of this fish but to be due rather to failure to identify it, for specimens (misidentified as L. piscatorius) dating from the last century have been found in the British Museum (Natural History) collection.The distinctive characters of both species are given.
The Change With Host Age of the Composition of the Ancyrocephaline (Monogenean) Populations Of Parasites On Thick-Lipped Grey Mullets At Plymouth
Authors: Anderson M. 
Published: May 2009

In investigating the parasites of adult thick-lipped grey mullets Chelon labrosus (Risso, 1826) at Plymouth these fishes were found to be infected exclusively with an ancyrocephaline gill monogenean identified as Ligophorus angustus Euzet & Suriano, 1977. When, at a later date, some juvenile C. labrosus were examined ancyrocephalines were again collected; however, quite unexpectedly, these parasites were not juvenile L. angustus but belonged exclusively to a new species of ancyrocephaline subsequently reported as Ergenstrema labrosi Anderson, 1981.It seemed then that there might be a situation of considerable biological interest in which young fishes were characterized by one host-specific monogenean and older mullets by another. Although a change in the species composition of the total parasite fauna of mullets with age has been reported previously by Reshetnikova (1955) for golden grey mullet Liza aurata of the Black Sea, a change of monogenean species has never previously been recorded.From an examination of the literature (e.g. Hickling, 1970) on the life history of the British thick-lipped grey mullet it was inferred that the situation described above might be associated with the migratory habits of the fish and in particular the different environments inhabited by young and old mullets; while there may be many factors (e.g. oxygen, temperature, pH, etc.) which differ between the open sea and tidal pools, inhabited by old and young fishes respectively, the most obvious one is that of salinity. Hence, in addition to establishing the identity and frequency of the ancyrocephaline infections with host age, it was decided to make investigations on the salinity tolerances of L. angustus and E. labrosi.
Sterols of the Cephalopod Spirula Spirula
Authors: Ballantine James A. , Roberts John C. , Morris Robert J. 
Published: May 2009

The sterol biochemistry of the highly advanced molluscan class – the cephalopods – is poorly understood. Few analyses of their component sterols have been published in which GC-MS has been employed (Voogt, 1973; Idler et al. 1978; ApSimon & Burnell, 1980) and these have only involved 5 species.From the available data the cephalopods appear to have a much simpler sterol make-up than the other less-advanced molluscs. Cholesterol appears to be easily the predominant sterol (ca. 90%) with minor amounts of up to 10 other common marine sterols. Of the species analysed, four (Sepia officinalis, Octopus vulgaris, Eledone aldrovandi and Illex illecebrosus) had a very similar major and minor sterol composition. Only the more primitive Nautilus sp. (Idler et al. 1978) had a noticeably different minor sterol composition.Voogt (1973) reported cephalopods to be able to synthesise sterols though molluscs generally appear only to be able to carry out this biosynthesis slowly (Goad, 1978). Cephalopods are extremely active carnivores and thus would be expected to have a diverse diet. If their component sterols are of a dietary origin, a considerable variation in their minor sterol composition might be expected on the basis of the range in sterol composition reported for pelagic organisms (e.g. Morris & Culkin, 1977), many of which may be possible dietary components.Detailed knowledge however of cephalopod diets is limited. Quite apart from the fact that healthy specimens are rarely caught in nets, those that are caught often feed voraciously on the other organisms trapped in the net prior to being brought on board for examination.
The Behaviour ofArenicola MarinaL. in Sand, and the Role of Spontaneous Activity Cycles
Authors: Wells G. P. 
Published: May 2009

Worms were allowed to burrow in sand in the laboratory. The general form of their burrows resembled that found in the field. Their behaviour was studied by continuously recording the water movements through the burrows for periods up to 3 weeks.Whenever the worms were feeding from a gradually subsiding cone and piling up castings, as they do in the field, a characteristic cyclical pattern was traced. This was marked by conspicuous diphasic excursions at intervals of about 40 min. Defaecation occurs at the summit of the first phase. By comparison with records got from worms in glass tubes (Wells, 1949), it is inferred that the first phase consists of tailward locomotion to the sand surface, and the second to headward irrigation accompanied by gentle creeping back to the feeding point. The whole cycle is identical with the intermittent irrigation cycle shown in glass tubes.
The Distribution of Lugworms (Arenicola Marina L.) over the Flats at Whitstable
Authors: Chapman Garth , Newell G. E. 
Published: May 2009

It has been shown that the main factor which influences the local distribution of the lugworm at Whitstable is the depth of the muddy sand overlying the clay stratum below.In places this clay is furrowed by straight channels which are revealed only by the arrangement of the lugworm castings. These are more numerous along the channels.Migration of adult lugworms has been shown to occur, most freely in the spring.
The Later Larval Life of Arenicola Marina L
Authors: Newell G. E. 
Published: May 2009

Larvae with three and four chaetigerous segments and also an early post-larval stage of Arenicola marina are described with figures. These are all bottomdwelling stages enclosed in mucous tubes and were collected from the pebble and Fucus zone at Whitstable.The rinding of these larvae furnishes additional evidence for the view that, except when migrating in the water to new habitats, the lugworm possesses no pelagic larval stage in its life history.
The Mechanism of Opening and Closing ofCalliactis Parasitica
Authors: Chapman Garth 
Published: May 2009

Experiments are described which suggest that Calliactis behaves as a closed animal in its movements, although its stomodaeum appears to be widely open to the exterior.Observations of the movements of the animal are correlated with variations of the internal pressure. It is shown that expansion is not merely ‘passive relaxation’, but is generally accompanied by a rise in pressure which is, however, much lower than that which accompanies rapid closing.It is concluded that the fluid-muscle system ofCalliactisbehaves in a similar way to that of other soft-bodied invertebrates, but that the system works at a much lower pressure.